Gao X

References (81)

Title : Ultrathin C(3)N(4) nanosheets-based oxidase-like 2D fluorescence nanozyme for dual-mode detection of organophosphorus pesticides - Shen_2023_J.Hazard.Mater_451_131171
Author(s) : Shen Y , Gao X , Chen H , Wei Y , Yang H , Gu Y
Ref : J Hazard Mater , 451 :131171 , 2023
Abstract : Engineering efficient dual-mode portable sensor with built-in cross reference correction is of great significance for onsite reliable and precise detection of organophosphorus pesticides (OPs) and evading the false-positive outputs, especially in emergency case. Currently, most nanozyme-based sensors for OPs monitoring primarily replied on the peroxidase-like activity, which involved unstable and toxic H(2)O(2). In this scenario, a hybrid oxidase-like 2D fluorescence nanozyme (PtPdNPs@g-C(3)N(4)) was yielded by in situ growing PtPdNPs in the ultrathin two-dimensional (2D) graphitic carbon nitride (g-C(3)N(4)) nanosheet. When acetylcholinesterase (AChE) hydrolyzed acetylthiocholine (ATCh) to thiocholine (TCh), it ablated O(2)(-) from the dissolved O(2) catalyzed by PtPdNPs@g-C(3)N(4)'s oxidase-like activity, hampering the oxidation of o-phenylenediamine (OPD) into 2,3-diaminophenothiazine (DAP). Consequently, with the increasing concentration of OPs which inhibited the blocking effect by inactivating AChE, the produced DAP caused an apparent color change and a dual-color ratiometric fluorescence change in the response system. Through integrating into a smartphone, a H(2)O(2)-free 2D nanozyme-based onsite colorimetric and fluorescence dual-mode visual imaging sensor for OPs was proposed with acceptable results in real samples, which holds vast promise for further development of commercial point-of-care testing platform in early warning and controlling of OPs pollution for safeguarding environmental health and food safety.
ESTHER : Shen_2023_J.Hazard.Mater_451_131171
PubMedSearch : Shen_2023_J.Hazard.Mater_451_131171
PubMedID: 36913745

Title : Development of a fluorescent sensor based on TPE-Fc and GSH-AuNCs for the detection of organophosphorus pesticide residues in vegetables - Wang_2023_Food.Chem_431_137067
Author(s) : Wang X , Yu H , Li Q , Tian Y , Gao X , Zhang W , Sun Z , Mou Y , Sun X , Guo Y , Li F
Ref : Food Chem , 431 :137067 , 2023
Abstract : A novel dual-signal fluorescent sensor was developed for detecting organophosphorus pesticides (OPs). It relies on the catalytic activities of acetylcholinesterase (AChE) and choline oxidase (ChOx) to generate hydrogen peroxide (H(2)O(2)) through the conversion of acetylcholine (ACh) to choline.H(2)O(2) then oxidizes ferrocene-modified tetraphenylethylene (TPE-Fc) to its oxidized state (TPE-Fc(+)), resulting in enhanced cyan fluorescence due to aggregation. Simultaneously, ferrocene oxidation generates hydroxyl radicals (OH), causing a decrease in orange fluorescence of glutathione-synthesized gold nanoclusters (GSH-AuNCs). The presence of OPs restricts AChE activity, reducing H(2)O(2) production. Increasing OPs concentration leads to decreased cyan fluorescence and increased orange fluorescence, enabling visual OPs detection. The sensor has a linear dynamic range of 10-2000 ng/mL with a detection limit of 2.05 ng/mL. Smartphone-based color identification and a WeChat mini program were utilized for rapid OPs analysis with successful outcomes.
ESTHER : Wang_2023_Food.Chem_431_137067
PubMedSearch : Wang_2023_Food.Chem_431_137067
PubMedID: 37579609

Title : ZnO-rGO-based electrochemical biosensor for the detection of organophosphorus pesticides - Liu_2023_Bioelectrochemistry_156_108599
Author(s) : Liu Y , Xiao Y , Zhang Y , Gao X , Wang H , Niu B , Li W
Ref : Bioelectrochemistry , 156 :108599 , 2023
Abstract : The accurate determination of organophosphorus pesticide residues is of great importance for human disease monitoring and environmental safety. Numerous detection methods exist, among which sensitive monitoring of organophosphorus compounds using electrochemical sensors has gradually become a research hotspot. This paper used acetylcholinesterase (AChE) as an indicator anchored on a zinc oxide-reduced graphene oxide (ZnO-rGO) composite rich in active sites, in which green non-toxic zinc oxide (ZnO) nanomaterials were uniformly distributed on the reduced graphene for rapid detection of organophosphorus. The effects of different ratios of ZnO to reduced graphene on the performance of ZnO-rGO nanocomposites were investigated. The AChE/ZnO-rGO biosensor detects organophosphorus by electrochemical inhibition of acetylcholinesterase in the presence of organophosphorus. The developed electrochemical biosensor has high selectivity and good linearity, and the ZnO-rGO nanocomposite as a matrix for immobilization of acetylcholinesterase and detection of organophosphorus has the potential for highly sensitive pesticide detection.
ESTHER : Liu_2023_Bioelectrochemistry_156_108599
PubMedSearch : Liu_2023_Bioelectrochemistry_156_108599
PubMedID: 37988979

Title : Network pharmacology combined with an animal model to reveal the material basis and mechanism of Amomum villosum in alleviating constipation in mice - Liu_2023_Gene_897_148064
Author(s) : Liu S , Zhao Y , Li S , Li Y , Liu L , Sheng J , Tian Y , Gao X
Ref : Gene , 897 :148064 , 2023
Abstract : Constipation is a prevalent gastrointestinal disorder, with its prevalence showing an annual upward trend. There are many factors involved in the occurrence of constipation, such as abnormal smooth muscle contraction and disorders of gastrointestinal hormone secretion. Amomum villosum (A. villosum) has been proven to be effective in improving digestive system diseases, but there is no report on improving constipation. Therefore, we used network pharmacology prediction combined with animal experiments to explore the key active components of A. villosum and their pharmacological mechanisms. The results of network pharmacological prediction showed that beta-sitosterol was the key laxative compound of A. villosum, which may play a laxative role by activating the adrenoceptor alpha 1 A-myosin light chain (ADRA1A-MLC) pathway. Further animal experiments showed that beta-sitosterol could significantly shorten the time to first black stool; increase faecal weight, faecal number, and faecal water content; and promote gastrointestinal motility. beta-sitosterol may promote intestinal motility by upregulating the expression of ADRA1A and myosin light chain 9 (Myl9) mRNA and protein in the colon, thereby activating the ADRA1A-MLC signalling pathway. In addition, it is possible to improve constipation symptoms by regulating serum neurotransmitters and gastrointestinal motility-related factors, such as the serum content of 5-hydroxytryptamine (5-HT) and acetylcholinesterase (AchE) and the mRNA expression of 5-hydroxytryptamine receptor 4 (5-HT4), stem cell factor (SCF), stem cell factor receptor (c-Kit) and smooth muscle myosin light chain kinase (smMLCK) in the colon. These results lay a foundation for the application of A. villosum and beta-sitosterol in constipation.
ESTHER : Liu_2023_Gene_897_148064
PubMedSearch : Liu_2023_Gene_897_148064
PubMedID: 38065427

Title : Crystal structure of the GDSL family esterase EstL5 in complex with PMSF reveals a branch channel of the active site pocket - Chen_2023_Acta.Biochim.Biophys.Sin.(Shanghai)__
Author(s) : Chen R , Gao X , Nie T , Wu J , Wang L , Osman A , Feng Y , Li X , Zhang Y
Ref : Acta Biochim Biophys Sin (Shanghai) , : , 2023
Abstract : Esterases/lipases from the GDSL family have potential applications in the hydrolysis and synthesis of important esters of pharmaceutical, food, and biotechnical interests. However, the structural and functional understanding of GDSL enzymes is still limited. Here, we report the crystal structure of the GDSL family esterase EstL5 complexed with PMSF at 2.34 A resolution. Intriguingly, the PMSF binding site is not located at the active site pocket but is situated in a surface cavity. At the active site, we note that there is a trapped crystallization solvent 1,6-hexanediol, which mimics the bound ester chain, allowing for further definition of the active site pocket of EstL5. The most striking structural feature of EstL5 is the presence of a unique channel, which extends approximately 18.9 A, with a bottleneck radius of 6.8 A, connecting the active-site pocket and the surface cavity. Replacement of Ser205 with the bulk aromatic residue Trp or Phe could partially block the channel at one end and perturb its access. Reduced enzymatic activity is found in the EstL5 S205W and EstL5 S205F mutants, suggesting the functional relevance of the channel to enzyme catalysis. Our study provides valuable information regarding the properties of the GDSL-family enzymes for designing more efficient and robust biocatalysts.
ESTHER : Chen_2023_Acta.Biochim.Biophys.Sin.(Shanghai)__
PubMedSearch : Chen_2023_Acta.Biochim.Biophys.Sin.(Shanghai)__
PubMedID: 37705347

Title : Cymbopogon citratus (DC.) Stapf aqueous extract ameliorates loperamide-induced constipation in mice by promoting gastrointestinal motility and regulating the gut microbiota - Gao_2022_Front.Microbiol_13_1017804
Author(s) : Gao X , Hu Y , Tao Y , Liu S , Chen H , Li J , Zhao Y , Sheng J , Tian Y , Fan Y
Ref : Front Microbiol , 13 :1017804 , 2022
Abstract : Slow transit constipation (STC) is the most common type of functional constipation. Drugs with good effects and few side effects are urgently needed form the treatment of STC. Cymbopogon citratus (DC.) Stapf (CC) is an important medicinal and edible spice plant. The wide range of biological activities suggested that CC may have laxative effects, but thus far, it has not been reported. In this study, the loperamide-induced STC mouse model was used to evaluate the laxative effect of the aqueous extract of CC (CCAE), and the laxative mechanism was systematically explored from the perspectives of the enteric nervous system (ENS), neurotransmitter secretion, gastrointestinal motility factors, intestinal inflammation, gut barrier and gut microbiota. The results showed that CCAE not only decreased the serum vasoactive intestinal polypeptide (VIP), induced nitric oxide synthases (iNOS), and acetylcholinesterase (AchE) in STC mice but also increased the expression of gastrointestinal motility factors in colonic interstitial cells of Cajal (ICCs) and smooth muscle cells (SMCs), thereby significantly shortening the defecation time and improving the gastrointestinal transit rate. The significantly affected gastrointestinal motility factors included stem cell factor receptor (c-Kit), stem cell factor (SCF), anoctamin 1 (Ano1), ryanodine receptor 3 (RyR3), smooth muscle myosin light chain kinase (smMLCK) and Connexin 43 (Cx43). Meanwhile, CCAE could repair loperamide-induced intestinal inflammation and intestinal barrier damage by reducing the expression of the pro-inflammatory factor IL-1beta and increasing the expression of the anti-inflammatory factor IL-10, chemical barrier (Muc-2) and mechanical barrier (Cldn4, Cldn12, Occludin, ZO-1, and ZO-2). Interestingly, CCAE could also partially restore loperamide-induced gut microbial dysbiosis in various aspects, such as microbial diversity, community structure and species composition. Importantly, we established a complex but clear network between gut microbiota and host parameters. Muribaculaceae, Lachnospiraceae and UCG-010 showed the most interesting associations with the laxative phenotypes; several other specific taxa showed significant associations with serum neurotransmitters, gastrointestinal motility factors, intestinal inflammation, and the gut barrier. These findings suggested that CCAE might promote intestinal motility by modulating the ENS-ICCs-SMCs network, intestinal inflammation, intestinal barrier and gut microbiota. CC may be an effective and safe therapeutic choice for STC.
ESTHER : Gao_2022_Front.Microbiol_13_1017804
PubMedSearch : Gao_2022_Front.Microbiol_13_1017804
PubMedID: 36267178

Title : Evaluation of Antioxidative and Neuroprotective Activities of Total Flavonoids From Sea Buckthorn (Hippophae rhamnoides L.) - Wang_2022_Front.Nutr_9_861097
Author(s) : Wang Z , Wang W , Zhu C , Gao X , Chu W
Ref : Front Nutr , 9 :861097 , 2022
Abstract : The aim of this study was to investigate the antioxidative and neuroprotective activities of total flavonoids from sea buckthorn (Hippophae rhamnoides L.) (TFH). Results indicated that TFH possessed DPPH radicals, hydroxyl radicals and superoxide anions scavenging activities. The neuroprotective potential was assessed with acetylcholinesterase (AChE) and monoamine oxidase A (MAO-A). The inhibition rates of AChE and MAO-A by 50 microg/ml TFH were 75.85 and 51.22%, respectively. The in vivo antioxidative and neuroprotective potential of TFH were explored in Caenorhabditis elegans. In the longevity assay, TFH (50 microg/ml) significantly increased the lifespan of wild-type C. elegans (29.40%). In the hydrogen peroxide-induced oxidative stress challenge, the antioxidant capacity of TFH-treated wild-type C. elegans was significantly enhanced. The C. elegans mutant strain CL4176 was used to study the neuroprotective effect of TFH in vivo. Results showed that TFH significantly delayed paralysis in C. elegans CL4176. Our study suggested total flavonoids from sea buckthorn (Hippophae rhamnoides L.) had the potential as an antioxidative and neuroprotective agent to extend aging and treat neurodegenerative diseases.
ESTHER : Wang_2022_Front.Nutr_9_861097
PubMedSearch : Wang_2022_Front.Nutr_9_861097
PubMedID: 35799585

Title : Impact of Imidacloprid Resistance on the Demographic Traits and Expressions of Associated Genes in Aphis gossypii Glover - Ullah_2022_Toxics_10_
Author(s) : Ullah F , Xu X , GUl H , Gncan A , Hafeez M , Gao X , Song D
Ref : Toxics , 10 : , 2022
Abstract : Imidacloprid is one of the most widely used neonicotinoid insecticides to control sap-sucking insect pests, including Aphis gossypii. The intensive application of chemical insecticides to A. gossypii led to the development of resistance against several insecticides, including imidacloprid. Therefore, it is crucial to understand the association between imidacloprid resistance and the fitness of A. gossypii to limit the spread of the resistant population under field contexts. In this study, we used the age-stage, two-sex life table method to comprehensively investigate the fitness of imidacloprid resistant (ImR) and susceptible strains (SS) of melon aphids. Results showed that ImR aphids have prolonged developmental stages and decreased longevity, fecundity, and reproductive days. The key demographic parameters (r, , and R(0)) were significantly reduced in ImR strain compared to SS aphids. Additionally, the molecular mechanism for fitness costs was investigated by comparing the expression profile of juvenile hormone-binding protein (JHBP), juvenile hormone epoxide hydrolase (JHEH), juvenile hormone acid O-methyltransferase (JHAMT), Vitellogenin (Vg), ecdysone receptor (EcR), and ultraspiracle protein (USP) supposed to be associated with development and reproduction in insects. The results of RT-qPCR showed that EcR, JHBP, JHAMT, JHEH, and Vg genes were downregulated, while USP was statistically the same in ImR A. gossypii compared to the SS strain. Together, these results provide in-depth information about the occurrence and magnitude of fitness costs against imidacloprid resistance that could help manage the evolution and spread of A. gossypii resistance in field populations.
ESTHER : Ullah_2022_Toxics_10_
PubMedSearch : Ullah_2022_Toxics_10_
PubMedID: 36355949

Title : A highly sensitive and selective enzyme activated fluorescent probe for in vivo profiling of carboxylesterase 2 - Liu_2022_Anal.Chim.Acta_1221_340126
Author(s) : Liu SY , Zou X , Guo Y , Gao X
Ref : Anal Chim Acta , 1221 :340126 , 2022
Abstract : Carboxylesterase 2 (CES2) is a serine-type hydrolase that plays important roles in xenobiotic detoxification and lipid metabolism. Its abnormal expression is highly associated with diseases such as diabetes and carcinoma. To date, intense attention has been attracted to CES2 targeted drug discovery and disease diagnosis. Thus, to further explore the physiological function of CES2 is of great importance. However, until now, most medical research on CES2 function and activity assays is still dependent on conventional methods, which could hardly specify CES2 activity. Therefore, there is an urgent need to develop efficient tools for selective measurement and sensing of endogenous CES2 in complicated biological system. In this study, we report the design and construction of an enzyme-activated fluorescent probe for CES2 activity sensing. The acquired probe DXMB was characterized as a highly specific and sensitive fluorescent probe for CES2 and possessed superior binding affinity, overall catalytic efficiency, and reaction velocity when compared with the reported CES2 probes. By application of DXMB into living system, it was capable of sensing endogenous CES2 in living cells, dynamic monitoring CES2 in zebrafish development, and visualizing tissue distribution of CES2 in nude mice. Most importantly, abnormally elevated CES2 activity in the intestine of diabetic model mice was first revealed, while significantly decreased CES2 activity in the liver was validated by DXMB. These results indicated that DXMB could serve as a vital tool for further CES2-related biological and medical research.
ESTHER : Liu_2022_Anal.Chim.Acta_1221_340126
PubMedSearch : Liu_2022_Anal.Chim.Acta_1221_340126
PubMedID: 35934362

Title : 5-Methyltetrahydrofolate Alleviates Memory Impairment in a Rat Model of Alzheimer's Disease Induced by D-Galactose and Aluminum Chloride - Zhang_2022_Int.J.Environ.Res.Public.Health_19_
Author(s) : Zhang Z , Wu H , Qi S , Tang Y , Qin C , Liu R , Zhang J , Cao Y , Gao X
Ref : Int J Environ Research Public Health , 19 : , 2022
Abstract : The effects of 5-methyltetrahydrofolate (5-MTHF) on a rat model of Alzheimer's disease (AD) induced by D-galactose (D-gal) and aluminum chloride (AlCl(3)) were investigated. Wistar rats were given an i.p. injection of 60 mg/kg D-gal and 10 mg/kg AlCl(3) to induce AD and three doses of 1 mg/kg, 5 mg/kg or 10 mg/kg 5-MTHF by oral gavage. A positive control group was treated with 1 mg/kg donepezil by gavage. Morris water maze performance showed that 5 and 10 mg/kg 5-MTHF significantly decreased escape latency and increased the number of platform crossings and time spent in the target quadrant for AD rats. The administration of 10 mg/kg 5-MTHF decreased the brain content of amyloid beta-protein 1-42 (Abeta(1-42)) and phosphorylated Tau protein (p-Tau) and decreased acetylcholinesterase and nitric oxide synthase activities. Superoxide dismutase activity, vascular endothelial growth factor level and glutamate concentration were increased, and malondialdehyde, endothelin-1, interleukin-6, tumor necrosis factor-alpha and nitric oxide decreased. The administration of 10 mg/kg 5-MTHF also increased the expression of disintegrin and metallopeptidase domain 10 mRNA and decreased the expression of beta-site amyloid precursor protein cleavage enzyme 1 mRNA. In summary, 5-MTHF alleviates memory impairment in a D-gal- and AlCl(3)-exposed rat model of AD. The inhibition of Abeta(1-42) and p-Tau release, reduced oxidative stress, the regulation of amyloid precursor protein processing and the release of excitatory amino acids and cytokines may be responsible.
ESTHER : Zhang_2022_Int.J.Environ.Res.Public.Health_19_
PubMedSearch : Zhang_2022_Int.J.Environ.Res.Public.Health_19_
PubMedID: 36554305

Title : Nematicidal activity of tirotundin and parthenolide isolated from Tithonia diversifolia and Chrysanthemum parthenium - Lan_2022_J.Environ.Sci.Health.B__1
Author(s) : Lan M , Gao X , Duan X , Li H , Yu H , Li J , Zhao Y , Hao X , Ding X , Wu G
Ref : J Environ Sci Health B , :1 , 2022
Abstract : Acetylcholinesterase (AChE) is an enzyme that catalyzes acetylcholine into choline and acetic acid. Conventional pesticides, including organophosphates and carbamates target and inhibit the activity of AChE. To obtain more pesticide precursors that meet the safety requirements, more than 200 compounds were screened. Tirotundin and parthenolide identified as potential neurotoxins to nematodes were isolated from Tithonia diversifolia and Chrysanthemum parthenium, respectively. Their IC(50) values were 6.89 +/- 0.30 and 5.51 +/- 0.23 microg/mL, respectively against the AChE isolated from Caenorhabditis elegans. AChE was inhibited in a dose-dependent manner using the two compounds. And the Lineweaver-Burk and Dixon plots indicated that tirotundin and parthenolide were reversible inhibitors against AChE, both inhibiting AChE in a mixed-type competitive manner and demonstrating these compounds may possess dual binding site AChE inhibitors. LC(50) values of tirotundin and parthenolide against C. elegans were 9.16 +/- 0.21 and 7.23 +/- 0.48 microg/mL, respectively. These results provide a certain theoretical basis for the development and utilization of novel pesticides.
ESTHER : Lan_2022_J.Environ.Sci.Health.B__1
PubMedSearch : Lan_2022_J.Environ.Sci.Health.B__1
PubMedID: 34983315

Title : Novel phenylpropanoids and isoflavone glycoside are isolated and identified from the carob pods (Ceratonia siliqua L.) - Peng_2022_Nat.Prod.Res__1
Author(s) : Peng ZT , Xia YJ , Yashiro T , Gao X , Dong TT , Tsim KWK , Wang HY
Ref : Nat Prod Res , :1 , 2022
Abstract : Two new phenylpropanoids (1 and 2) and one new isoflavone glycoside (3), along with nine known compounds (4 - 12), were isolated from the pod of Ceratonia siliqua L. Their chemical structures were elucidated based on extensive spectroscopic analyses (1 D and 2 D NMR, UV, IR, and HRESIMS) and compared with the literature data. In addition, all isolated compounds were evaluated in vitro for inhibitory activity against acetylcholinesterase (AChE). Compounds 4, 5, and 12 showed inhibitory activity against acetylcholinesterase (AChE) with IC(50) values ranging from 15.0 to 50.2 microM.
ESTHER : Peng_2022_Nat.Prod.Res__1
PubMedSearch : Peng_2022_Nat.Prod.Res__1
PubMedID: 35574610

Title : Resistance Mechanisms of Sitobion miscanthi (Hemiptera: Aphididae) to Malathion Revealed by Synergist Assay - Xu_2022_Insects_13_
Author(s) : Xu T , Lou K , Song D , Zhu B , Liang P , Gao X
Ref : Insects , 13 : , 2022
Abstract : A resistant strain (MRS) of Sitobion miscanthi was cultured by continuous selection with malathion for over 40 generations. The MRS exhibited 32.7-fold resistance to malathion compared to the susceptible strain (MSS) and 13.5-fold, 2.9-fold and 4.8-fold cross-resistance for omethoate, methomyl and beta-cypermethrin, respectively. However, no cross-resistance was found to imidacloprid in this resistant strain. The realized heritability for malathion resistance was 0.02. Inhibitors of esterase activity, both triphenyl phosphate (TPP) and S,S,S,-tributyl phosphorotrithioate (DEF) as synergists, exhibited significant synergism to malathion in the MRS strain, with 11.77-fold and 5.12-fold synergistic ratios, respectively, while piperonyl butoxide (PBO) and diethyl maleate (DEM) showed no significant synergism in the MRS strain. The biochemical assay indicated that carboxylesterase activity was higher in MRS than in MSS. These results suggest that the increase in esterase activity might play an important role in S. miscanthi resistance to malathion. Imidacloprid could be used as an alternative for malathion in the management of wheat aphid resistance.
ESTHER : Xu_2022_Insects_13_
PubMedSearch : Xu_2022_Insects_13_
PubMedID: 36421946

Title : Role of Bmal1 in mediating the cholinergic system to regulate the behavioral rhythm of nocturnal marine molluscs - Gao_2022_Comput.Struct.Biotechnol.J_20_2815
Author(s) : Gao X , Zhang M , Lyu M , Lin S , Luo X , You W , Ke C
Ref : Comput Struct Biotechnol J , 20 :2815 , 2022
Abstract : The circadian rhythm is one of the most general and important rhythms in biological organisms. In this study, continuous 24-h video recordings showed that the cumulative movement distance and duration of the abalone, Haliotis discus hannai, reached their maximum values between 20:00-00:00, but both were significantly lower between 08:00-12:00 than at any other time of day or night (P < 0.05). To investigate the causes of these diel differences in abalone movement behavior, their cerebral ganglia were harvested at 00:00 (group D) and 12:00 (group L) to screen for differentially expressed proteins using tandem mass tagging (TMT) quantitative proteomics. Seventy-five significantly different proteins were identified in group D vs. group L. The differences in acetylcholinesterase (AchE) expression levels between day- and nighttime and the key role in the cholinergic nervous system received particular attention during the investigation. A cosine rhythm analysis found that the concentration of acetylcholine (Ach) and the expression levels of AchE tended to be low during the day and high at night, and high during the day and low at night, respectively. However, the rhythmicity of the diel expression levels of acetylcholine receptor (nAchR) appeared to be insignificant (P > 0.05). Following the injection of three different concentrations of neostigmine methylsulfate, as an AchE inhibitor, the concentration of Ach in the hemolymph, and the expression levels of nAchR in the cerebral ganglia increased significantly (P < 0.05). Four hours after drug injection, the cumulative movement distance and duration of abalones were significantly higher than those in the uninjected control group, and the group injected with saline (P < 0.05). The expression levels of the core diurnal clock Bmal1 over a 24-h period also tended to be high during the day and low at night. First, a co-immunoprecipitation assay demonstrated the binding between Bmal1 and AchE or nAchR. A dual-luciferase gene test and electrophoretic mobility shift assay showed that Bmal1 bound to the promoter regions of AchE and nAchR. Twenty-four hours after silencing the Bmal1 gene, the expression levels of AchE and nAchR decreased significantly compared to those of the dsEGFP and PBS control groups, further showing that Bmal1 mediates the cholinergic system to regulate the behavioral rhythm of abalone. These findings shed light on the endocrine mechanism regulating the rhythmic behavior of abalone, and provide a reference for understanding the life history adaptation strategies of nocturnal organisms and the proliferation and protection of bottom dwelling economically important organisms.
ESTHER : Gao_2022_Comput.Struct.Biotechnol.J_20_2815
PubMedSearch : Gao_2022_Comput.Struct.Biotechnol.J_20_2815
PubMedID: 35765646

Title : Transport, Stability, and In Vivo Hypoglycemic Effect of a Broccoli-Derived DPP-IV Inhibitory Peptide VPLVM - Pei_2022_J.Agric.Food.Chem__
Author(s) : Pei J , Liu Z , Pan D , Zhao Y , Dang Y , Gao X
Ref : Journal of Agricultural and Food Chemistry , : , 2022
Abstract : Diabetes is a major metabolic disease that requires long-term pharmacotherapy. Bioactive peptides have unique advantages such as higher potency, selectivity, and safety over small molecules and have achieved great success in the treatment of diabetes. We previously isolated a dipeptidyl peptidase-IV (DPP-IV) inhibitory peptide VPLVM with IC(50) = 99.68 microM from the protein hydrolysates of broccoli stems and leaves. Here, we evaluated the interaction with DPP-IV, transport, stability, and in vivo hypoglycemic effects of VPLVM. VPLVM interacted closely and steadily with DPP-IV at S1 and S2 pockets. VPLVM had a good gastrointestinal enzyme resistance and was transported through the Caco-2 cell monolayer via paracellular diffusion and by the PepT1 with a P(app) of 6.96 x 10(-7) cm/s. VPLVM has a t(1/2) of 12.56 +/- 0.41 min in vitro plasma stability. In the oral glucose tolerance test, VPLVM showed an excellent hypoglycemic effect at 30 min after administration. VPLVM has potential as a candidate for the treatment of hyperglycemia.
ESTHER : Pei_2022_J.Agric.Food.Chem__
PubMedSearch : Pei_2022_J.Agric.Food.Chem__
PubMedID: 35436096

Title : Discovery of novel tacrine derivatives as potent antiproliferative agents with CDKs inhibitory property - Liu_2022_Bioorg.Chem_126_105875
Author(s) : Liu W , Wu L , Li D , Huang Y , Liu M , Tian C , Liu X , Jiang X , Hu X , Gao X , Xu Z , Lu H , Zhao Q
Ref : Bioorg Chem , 126 :105875 , 2022
Abstract : Tacrine was the first approved drug by the FDA for the treatment of Alzheimer's disease (AD) but was withdrawn from the market due to its dose-dependent hepatotoxicity. Herein, we describe our efforts toward the discovery of a novel series of tacrine derivatives for cancer therapeutics. Intensive structural modifications of tacrine led to the identification of N-(4-{9-[(3S)-3-aminopyrrolidin-1-yl]-5,6,7,8-tetrahydroacridin-2-yl}pyridin-2-yl)cyclopropanecarboxamide hydrochloride ((S)-45, ZLWT-37) as a potent antiproliferative agent (GI(50) = 0.029 microM for HCT116). In addition, ZLWT-37 exhibited lower inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) compared to tacrine. The in vitro studies demonstrated that ZLWT-37 could significantly induce apoptosis and arrest the cell cycle in the G2/M phase in HCT116 cells. The in vivo studies revealed that compound ZLWT-37 showed excellent antitumor efficacy in HCT116 xenograft tumor model and favorable pharmacokinetics profiles (F% = 28.70%) as well as low toxicity in the acute toxicity test with a median lethal dose (LD(50)) of 380.3 mg/kg. Encouragingly, ZLWT-37 had no obvious hepatotoxicity, nephrotoxicity, and hematologic toxicity. Kinase assay suggested that ZLWT-37 possessed potent cyclin-dependent kinase 9 (CDK9) inhibitory activity (IC(50) = 0.002 microM) and good selectivity over CDK2 (IC(50) = 0.054 microM). Collectively, these findings indicate that compound ZLWT-37 is a promising anti-cancer agent that deserves further preclinical evaluation.
ESTHER : Liu_2022_Bioorg.Chem_126_105875
PubMedSearch : Liu_2022_Bioorg.Chem_126_105875
PubMedID: 35623141

Title : Conceptual framework for the insect metamorphosis from larvae to pupae by transcriptomic profiling, a case study of Helicoverpa armigera (Lepidoptera: Noctuidae) - Gao_2022_BMC.Genomics_23_591
Author(s) : Gao X , Zhang J , Wu P , Shu R , Zhang H , Qin Q , Meng Q
Ref : BMC Genomics , 23 :591 , 2022
Abstract : BACKGROUND: Insect metamorphosis from larvae to pupae is one of the most important stages of insect life history. Relatively comprehensive information related to gene transcription profiles during lepidopteran metamorphosis is required to understand the molecular mechanism underlying this important stage. We conducted transcriptional profiling of the brain and fat body of the cotton bollworm Helicoverpa armigera (Lepidoptera: Noctuidae) during its transition from last instar larva into pupa to explore the physiological processes associated with different phases of metamorphosis. RESULTS: During metamorphosis, the differences in gene expression patterns and the number of differentially expressed genes in the fat body were found to be greater than those in the brain. Each stage had a specific gene expression pattern, which contributed to different physiological changes. A decrease in juvenile hormone levels at the feeding stage is associated with increased expression levels of two genes (juvenile hormone esterase, juvenile hormone epoxide hydrolase). The expression levels of neuropeptides were highly expressed at the feeding stage and the initiation of the wandering stage and less expressed at the prepupal stage and the initiation of the pupal stage. The transcription levels of many hormone (or neuropeptide) receptors were specifically increased at the initiation of the wandering stage in comparison with other stages. The expression levels of many autophagy-related genes in the fat body were found to be gradually upregulated during metamorphosis. The activation of apoptosis was probably related to enhanced expression of many key genes (Apaf1, IAP-binding motif 1 like, cathepsins, caspases). Active proliferation might be associated with enhanced expression levels in several factors (JNK pathway: jun-D; TGF-beta pathway: decapentaplegic, glass bottom boat; insulin pathway: insulin-like peptides from the fat body; Wnt pathway: wntless, TCF/Pangolin). CONCLUSIONS: This study revealed several vital physiological processes and molecular events of metamorphosis and provided valuable information for illustrating the process of insect metamorphosis from larvae to pupae.
ESTHER : Gao_2022_BMC.Genomics_23_591
PubMedSearch : Gao_2022_BMC.Genomics_23_591
PubMedID: 35963998

Title : The overexpression and variant of a P450 gene CYP6G4 associated with propoxur resistance in the housefly, Musca domestica L - You_2021_Pest.Manag.Sci__
Author(s) : You C , Shan C , Ma Z , Zhang Y , Zhao R , Gao X
Ref : Pest Manag Sci , : , 2021
Abstract : BACKGROUND: The control of housefly, Musca domestica, heavily relies on the application of insecticides. Propoxur, a carbamate, was widely used for vector control. The housefly populations with high propoxur resistance displayed the point mutations and overexpression of the acetylcholinesterase. However, the roles of cytochrome P450 monoxygenases (P450s), as a kind of the important detoxification enzymes, remain poorly understand in the housefly resistant to propoxur. RESULTS: P450s were implied to contribute to propoxur resistance based on the synergism of PBO and the increase of P450 enzyme activity in the propoxur resistance near-isogenic line (N-PRS). Five P450 (CYP6G4, CYP6A25, CYP304A1, CYP6D3, and CYP6A1) genes by RNA-seq comparison were significantly up-regulated in the N-PRS strain with >1035-fold resistance to propoxur. A total of thirteen nonsynonymous mutations of three P450 genes (CYP6G4, CYP6D3, and CYP6D8) were found in the N-PRS strain. The amino acid substitutions of CYP6D3 and CYP6D8 were probably not resistance-associated single nucleotide polymorphisms (SNPs) because they were also found in the aabys susceptible strain. However, CYP6G4 variant in the N-PRS strain was not found in the aabys strain. The conjoint analysis of mutations and a series of genetic crosses exhibited that the housefly propoxur resistance was strongly associated with the mutations of CYP6G4 gene. CONCLUSION: Our results suggested that a combination of upregulated transcript levels and mutations of CYP6G4 contributed to propoxur resistance in the housefly. This article is protected by copyright. All rights reserved.
ESTHER : You_2021_Pest.Manag.Sci__
PubMedSearch : You_2021_Pest.Manag.Sci__
PubMedID: 33942965

Title : A GRN Autocrine-Dependent FAM135B\/AKT\/mTOR Feedforward Loop Promotes Esophageal Squamous Cell Carcinoma Progression - Dong_2021_Cancer.Res_81_910
Author(s) : Dong D , Zhang W , Xiao W , Wu Q , Cao Y , Gao X , Huang L , Wang Y , Chen J , Wang W , Zhan Q
Ref : Cancer Research , 81 :910 , 2021
Abstract : Esophageal squamous cell carcinoma (ESCC) is one of the most common and deadly diseases. In our previous comprehensive genomics study, we found that family with sequence similarity 135 member B (FAM135B) was a novel cancer-related gene, yet its biological functions and molecular mechanisms remain unclear. In this study, we demonstrate that the protein levels of FAM135B are significantly higher in ESCC tissues than in precancerous tissues, and high expression of FAM135B correlates with poorer clinical prognosis. Ectopic expression of FAM135B promoted ESCC cell proliferation in vitro and in vivo, likely through its direct interaction with growth factor GRN, thus forming a feedforward loop with AKT/mTOR signaling. Patients with ESCC with overexpression of both FAM135B and GRN had worse prognosis; multivariate Cox model analysis indicated that high expression of both FAM135B and GRN was an independent prognostic factor for patients with ESCC. FAM135B transgenic mice bore heavier tumor burden than wild-type mice and survived a relatively shorter lifespan after 4-nitroquinoline 1-oxide treatment. In addition, serum level of GRN in transgenic mice was higher than in wild-type mice, suggesting that serum GRN levels might provide diagnostic discrimination for patients with ESCC. These findings suggest that the interaction between FAM135B and GRN plays critical roles in the regulation of ESCC progression and both FAM135B and GRN might be potential therapeutic targets and prognostic factors in ESCC. SIGNIFICANCE: These findings investigate the mechanisms of FAM135B in promoting ESCC progression and suggest new potential prognostic biomarkers and therapeutic targets in patients with ESCC.
ESTHER : Dong_2021_Cancer.Res_81_910
PubMedSearch : Dong_2021_Cancer.Res_81_910
PubMedID: 33323378
Gene_locus related to this paper: human-FAM135B

Title : Characterization of the insecticide detoxification carboxylesterase Boest1 from Bradysia odoriphaga Yang et Zhang (Diptera:Sciaridae) - Ding_2021_Pest.Manag.Sci__
Author(s) : Ding Q , Xu X , Sang Z , Wang R , Ullah F , Gao X , Song D
Ref : Pest Manag Sci , : , 2021
Abstract : BACKGROUND: In insects, carboxylesterases (CarEs) are enzymes involved in the detoxification of insecticides. However, the molecular mechanism of CarE-mediated insecticide metabolism in Bradysia odoriphaga, a serious agricultural pest, remains unclear. The aim of this study is to investigate the detoxification process of malathion, bifenthrin, and imidacloprid by B. odoriphaga carboxylesterase (Boest1). RESULTS: An alpha class CarE gene Boest1 was cloned from B. odoriphaga. The results of real-time quantitative PCR showed that Boest1 is up-regulated with age during the larval stage, and the level of transcription of Boest1 is higher in the midgut and Malpighian tubule than in other tissues. The expression level of Boest1 was significantly increased after exposure to malathion and bifenthrin. Recombinant BoEST1 expressed in vitro showed high catalytic activity toward alpha-naphthyl acetate, which was substantially inhibited by malathion and triphenyl phosphate. The in vitro metabolism assays showed that BoEST1 demonstrates hydrolytic capacity toward malathion and bifenthrin but not imidacloprid. The binding free energy analysis indicates that BoEST1 has a higher affinity for malathion and bifenthrin than imidacloprid. CONCLUSION: These results suggest that BoEST1 plays a role in the breakdown of insecticides and may be involved in the development of resistance in the Chinese chive pest B. odoriphaga; our findings also provide data for better pest management and perspectives for new pesticides development. This article is protected by copyright. All rights reserved.
ESTHER : Ding_2021_Pest.Manag.Sci__
PubMedSearch : Ding_2021_Pest.Manag.Sci__
PubMedID: 34596943
Gene_locus related to this paper: 9dipt-Boest1 , braco-est1

Title : Characterization and functional analysis of two acetylcholinesterase genes in Bradysia odoriphaga Yang et Zhang (Diptera: Sciaridae) - Ding_2021_Pestic.Biochem.Physiol_174_104807
Author(s) : Ding Q , Xu X , Wang X , Ullah F , Gao X , Song D
Ref : Pestic Biochem Physiol , 174 :104807 , 2021
Abstract : Two acetylcholinesterase genes (Boace1 and Boace2) were cloned from Bradysia odoriphaga, a devastating soil pest that mainly damages Chinese chives. The Boace1 encodes BoAChE1 protein consisting of 696 amino acid residues, while Boace2 encodes BoAChE2 containing 638 amino acids. Phylogenetic analysis showed that Boace1 and Boace2 are appeared to be distinct clusters. The gene expression patterns at different development stages and various body parts tissues were examined, and their biological functions were characterized by RNA interference and analog docking prediction. The results showed that both Boace genes were expressed in all developmental stages and examined tissues. The transcript level of Boace2 was significantly higher than Boace1 in all tested samples, and Boace1 was found most abundant in the head while Boace2 was highly expressed in the fat body of B. odoriphaga. The silencing of Boace1 and Boace2 significantly decreased the AChE activity of 36.6% and 14.8% separately, and increased the susceptibility of B. odoriphaga to phoxim, with 60.8% and 44.7% mortality. Besides, overexpression and gene duplication of Boace1 were found in two field resistant populations, and two major mutations, A319S and G400V, were detected in Boace1. Moreover, the docking results revealed that BoAChE1 had a higher affinity towards organophosphorus than BoAChE2. It is concluded that Boace2 is the most abundant ace type in B. odoriphaga, while both Boace play vital roles. Boace1 might play a major neurological function and more likely be the prime target for insecticides, while Boace2 might play some important unidentified roles.
ESTHER : Ding_2021_Pestic.Biochem.Physiol_174_104807
PubMedSearch : Ding_2021_Pestic.Biochem.Physiol_174_104807
PubMedID: 33838708
Gene_locus related to this paper: 9dipt-MT380203 , 9dipt-MT380204

Title : Inhibitory activities of flavonoids from Eupatorium adenophorum against acetylcholinesterase - Li_2020_Pestic.Biochem.Physiol_170_104701
Author(s) : Li M , Gao X , Lan M , Liao X , Su F , Fan L , Zhao Y , Hao X , Wu G , Ding X
Ref : Pestic Biochem Physiol , 170 :104701 , 2020
Abstract : Fifteen flavonoids isolated from the Eupatorium adenophorum showed inhibitory activities against acetylcholinesterase (AChE) isolated from Caenorhabditis elegans and Spodoptera litura. Their IC(50) values ranged from 12.54 to 89.06mug/mL and 12.08 to 86.01mug/mL, respectively against the AChE isolated from the nematode and insect species. AChE was inhibited in a dose-dependent manner by all tested flavonoids, The isolated compound quercetagetin-7-O-(6-O-caffeoyl-beta-D-glucopyranoside) displayed the highest inhibitory effect against AChE from C. elegans and S. litura, with IC(50) values of 12.54 mug/mL and 12.58 mug/mL, respectively. The structure-activity relationship of flavonoids on the inhibitory activities indicated that additional phenolic hydroxyl groups in the glucose were favorable for their inhibitory effects and the degree of increase in inhibitory activity also depended on the number of phenolic hydroxyl groups. The Lineweaver-Burk and Dixon plots indicated that quercetagetin-7-O-(6-O-caffeoyl-beta-d-glucopyranoside) is a reversible inhibitor against AChE. Quercetagetin-7-O-(6-O-caffeoyl-beta-d-glucopyranoside), 5,4'-Dihydroxytlavone and quercetin-3-O-beta-d-glucopyranoside inhibited AChE in a mixed-type competitive manner and these compounds might be the dual binding site AChE inhibitors. Further, nine compounds showed poisonous effects against C. elegans and inhibitory effects on the growth and development of S. litura.
ESTHER : Li_2020_Pestic.Biochem.Physiol_170_104701
PubMedSearch : Li_2020_Pestic.Biochem.Physiol_170_104701
PubMedID: 32980054

Title : The overexpression of three cytochrome P450 genes CYP6CY14, CYP6CY22 and CYP6UN1 contributed to metabolic resistance to dinotefuran in melon\/cotton aphid, Aphis gossypii Glover - Chen_2020_Pestic.Biochem.Physiol_167_104601
Author(s) : Chen A , Zhang H , Shan T , Shi X , Gao X
Ref : Pestic Biochem Physiol , 167 :104601 , 2020
Abstract : Dinotefuran, the third-generation neonicotinoid, has been applied against melon/cotton aphid Aphis gossypii Glover in China. The risk of resistance development, cross-resistance pattern and potential resistance mechanism of dinotefuran in A. gossypii were investigated. A dinotefuran-resistant strain of A. gossypii (DinR) with 74.7-fold resistance was established by continuous selection using dinotefuran. The DinR strain showed a medium level of cross resistance to thiamethoxam (15.2-fold), but no cross resistance to imidacloprid. The synergism assay indicated that piperonyl butoxide and triphenyl phosphate showed synergistic effects on dinotefuran toxicity to the DinR strain with a synergistic ratio of 8.3 and 2.5, respectively, while diethyl maleate showed no synergistic effect. The activities of cytochrome P450 monooxygenase and carboxylesterase were significantly higher in DinR strain than in susceptible strain (SS). Moreover, the gene expression results showed that CYP6CY14, CYP6CY22 and CYP6UN1 were significantly overexpressed in DinR strain compared with SS strain. The expression of CYP6CY14 was 5.8-fold higher in DinR strain than in SS strain. Additionally, the transcription of CYP6CY14, CYP6CY22 and CYP6UN1 in A. gossypii showed dose- and time-dependent responses to dinotefuran exposure. Furthermore, knockdown of CYP6CY14, CYP6CY22 and CYP6UN1 via RNA interference (RNAi) significantly increased mortality of A. gossypii, when A. gossypii was treated with dinotefuran. These results demonstrated the overexpression of CYP6CY14, CYP6CY22 and CYP6UN1 contributed to dinotefuran resistance in A. gossypii.
ESTHER : Chen_2020_Pestic.Biochem.Physiol_167_104601
PubMedSearch : Chen_2020_Pestic.Biochem.Physiol_167_104601
PubMedID: 32527429

Title : In vitro gastrointestinal digestibility of phytosterol oleogels: influence of self-assembled microstructures on emulsification efficiency and lipase activity - Dong_2020_Food.Funct_11_9503
Author(s) : Dong L , Lv M , Gao X , Zhang L , Rogers M , Cao Y , Lan Y
Ref : Food Funct , 11 :9503 , 2020
Abstract : The objective of this study was to investigate the influence of self-assembled microstructure on lipid digestibility in phytosterol (gamma-oryzanol and beta-sitosterol) oleogels. Different molar ratios of gamma-oryzanol and beta-sitosterol yielded a variety of crystal morphologies; the resulting gels were tested for their lipid emulsification efficiency, release rate of free fatty acids (FFAs) during lipolysis, and their effect on lipase behavior. Results indicated that oleogels were harder to emulsify when compared to oil samples. The emulsification efficiencly was affected by both the gel strength and crystal morphology of the self-assembled structures within phytosterol oleogels. In oil emulsions, intestinal digestion resulted in more extensive lipid droplet coalescence with increased particle size when compared to oleogel emulsions. The FFA release rate suggested that the extent of lipid digestion was correlated to the emulsification efficiency. The interfacial binding of lipase indicated that the amount of lipase adsorption was positively correlated to the interface area created during the emulsification process. Finally, isothermal titration calorimetry results indicated that self-assembled structures within these oleogels physically obstructed the interaction between lipase and lipid. Ultimately, this led to lower reaction rate during gastrointestinal digestion. Collectively, these results may have important implications in designing oleogel systems with controlled lipid digestibility as well as controlling the bioavailability of delivered lipid-soluble bioactive compounds.
ESTHER : Dong_2020_Food.Funct_11_9503
PubMedSearch : Dong_2020_Food.Funct_11_9503
PubMedID: 32955534

Title : Functional analysis of a carboxylesterase gene involved in beta-cypermethrin and phoxim resistance in Plutella xylostella (L.) - Li_2020_Pest.Manag.Sci_77_2097
Author(s) : Li R , Zhu B , Shan J , Li L , Liang P , Gao X
Ref : Pest Manag Sci , 77\ :2097 , 2020
Abstract : BACKGROUND: Carboxylesterases (CarEs) have been acquainted with their detoxification of xenobiotics in organism bodies, including insecticides. Overexpression of CarE genes has been considered playing important roles in insecticide resistance in insects, however it's involvement in multi-insecticide resistance have been rarely reported. This study aimed to assess the function of a CarE gene (PxalphaE8) in resistance to five insecticides in Plutella xylostella. RESULTS: The relative expressions of PxalphaE8 in three multi-insecticide-resistant populations including GD-2017, GD-2019 and HN were 14.8-, 19.5- and 28.0-fold higher than that in the susceptible one. Exposure to LC(25) of beta-cypermethrin, chlorantraniliprole, metaflumizone, phoxim and tebufenozide could induce the specific activity of CarEs and the relative expression of PxalphaE8 increase, while knockdown of PxalphaE8 expression dramatically reduced the activity of CarEs and increased the resistance of P. xylostella (GD-2019) larvae to beta-cypermethrin and phoxim by 47.4% and 45.5%, respectively. Further, a transgenic line of Drosophila melanogaster overexpressing PxalphaE8 was constructed and the bioassay results showed that the tolerance of the transgenic Drosophila to beta-cypermethrin and phoxim were 3.93- and 3.98-fold higher than that of the untransgenic line, respectively. CONCLUSION: These results provided the evidence that overexpression of PxalphaE8 is involved in resistance at least to both beta-cypermethrin and phoxim in multi-insecticide resistant P. xylostella populations, which would help in further understanding the molecular mechanisms of multi-insecticide resistance in this pest. This article is protected by copyright. All rights reserved.
ESTHER : Li_2020_Pest.Manag.Sci_77_2097
PubMedSearch : Li_2020_Pest.Manag.Sci_77_2097
PubMedID: 33342080
Gene_locus related to this paper: pluxy-PxalphaE8

Title : Esterase-mediated spinosad resistance in house flies Musca domestica (Diptera: Muscidae) - Zhang_2020_Ecotoxicology_29_35
Author(s) : Zhang Y , Guo M , Ma Z , You C , Gao X , Shi X
Ref : Ecotoxicology , 29 :35 , 2020
Abstract : Although esterase-mediated spinosad resistance has been proposed for several insects, the associated molecular mechanism remains poorly understood. In this study, we investigated the mechanism of esterase-based spinosad resistance in house flies using a susceptible strain (SSS) and a spinosad-resistant, near-isogenic line (N-SRS). Combined with the synergistic effect of DEF on spinosad in the N-SRS strain, decreased ali-esterase activity in the spinosad-resistant strain has implicated the involvement of mutant esterase in spinosad resistance in house flies. Examination of the carboxylesterase gene MdalphaE7 in the two strains revealed that four non-synonymous mutations (Trp(251)-Leu, Asp(273)-Glu, Ala(365)-Val, and Ile(396)-Val) may be associated with spinosad resistance in house flies. Single nucleotide polymorphism analysis further indicated a strong relationship between these four mutations and spinosad resistance. Moreover, quantitative real-time PCR revealed a female-linked MdalphaE7 expression pattern in the N-SRS strain, which may contribute to sex-differential spinosad resistance in house flies.
ESTHER : Zhang_2020_Ecotoxicology_29_35
PubMedSearch : Zhang_2020_Ecotoxicology_29_35
PubMedID: 31749037
Gene_locus related to this paper: musdo-EST23aes07

Title : Optimization of chemoenzymatic Baeyer-Villiger oxidation of cyclohexanone to sigma-caprolactone using response surface methodology - Zhang_2020_Biotechnol.Prog_36_e2901
Author(s) : Zhang Y , Jiang W , Lv K , Sun Y , Gao X , Zhao Q , Ren W , Wang F , Liu J
Ref : Biotechnol Prog , 36 :e2901 , 2020
Abstract : sigma-Caprolactone (sigma-CL) has attracted a great deal of attention and a high product concentration is of great significance for reducing production cost. The optimization of sigma-CL synthesis through chemoenzymatic Baeyer-Villiger oxidation mediated by immobilized Trichosporon laibacchii lipase was studied using response surface methodology (RSM). The yield of sigma-CL was 98.06% with about 1.2 M sigma-CL concentration that has a substantial increase mainly due to both better stability of the cross-linked immobilized lipase used and the optimum reaction conditions in which the concentration of cyclohexanone was 1.22 M, the molar ratio of cyclohexanone:urea hydrogen peroxide (UHP) was 1:1.3, and the reaction temperature was 56.5 degreesC. Based on our experimental results, it can be safely concluded that there are three reactions in this reaction system, not just two reactions, in which the third reaction is that the acetic acid formed reacts with UHP to form peracetic acid in situ catalyzed by the immobilized lipase. A quadratic polynomial model based on RSM experimental results was developed and the R(2) value of the equation is 0.9988, indicating that model can predict the experimental results with high precision. The experimental results also show that the molar ratio of cyclohexanone to UHP has very significant impact on the yield of sigma-CL (p < .0006).
ESTHER : Zhang_2020_Biotechnol.Prog_36_e2901
PubMedSearch : Zhang_2020_Biotechnol.Prog_36_e2901
PubMedID: 31465150

Title : Lemon essential oil ameliorates age-associated cognitive dysfunction via modulating hippocampal synaptic density and inhibiting acetylcholinesterase - Liu_2020_Aging.(Albany.NY)_12_
Author(s) : Liu B , Kou J , Li F , Huo D , Xu J , Zhou X , Meng D , Ghulam M , Artyom B , Gao X , Ma N , Han D
Ref : Aging (Albany NY) , 12 : , 2020
Abstract : The lemon essential oil (LEO), extracted from the fruit of lemon, has been used to treat multiple pathological diseases, such as diabetes, inflammation, cardiovascular diseases, depression and hepatobiliary dysfunction. The study was designed to study the effects of LEO on cognitive dysfunction induced by Alzheimer's disease (AD). We used APP/PS1 double transgene (APP/PS1) AD mice in the experiment; these mice exhibit significant deficits in synaptic density and hippocampal-dependent spatial related memory. The effects of LEO on learning and memory were examined using the Morris Water Maze (MWM) test, Novel object recognition test, and correlative indicators, including a neurotransmitter (acetylcholinesterase, AChE), a nerve growth factor (brain-derived neurotrophic factor, BDNF), a postsynaptic marker (PSD95), and presynaptic markers (synapsin-1, and synaptophysin), in APP/PS1 mice. Histopathology was performed to estimate the effects of LEO on AD mice. A significantly lowered brain AChE depression in APP/PS1 and wild-type C57BL/6L (WT) mice. PSD95/ Synaptophysin, the index of synaptic density, was noticeably improved in histopathologic changes. Hence, it can be summarized that memory-enhancing activity might be associated with a reduction in the AChE levels and is elevated by BDNF, PSD95, and synaptophysin through enhancing synaptic plasticity.
ESTHER : Liu_2020_Aging.(Albany.NY)_12_
PubMedSearch : Liu_2020_Aging.(Albany.NY)_12_
PubMedID: 32392535

Title : Cross-resistance and Fitness Cost Analysis of Resistance to Thiamethoxam in Melon and Cotton Aphid (Hemiptera: Aphididae) - Zhang_2020_J.Econ.Entomol__
Author(s) : Zhang H , Chen A , Shan T , Dong W , Shi X , Gao X
Ref : J Econ Entomol , : , 2020
Abstract : The melon/cotton aphid, Aphis gossypii Glover, is a notorious pest in many crops. The neonicotinoid insecticide thiamethoxam is widely used for A. gossypii control. To evaluate thiamethoxam resistance risk, a melon/cotton aphid strain with an extremely high level of resistance to thiamethoxam (>2,325.6-fold) was established after selection with thiamethoxam for 24 generations. Additionally, the cross-resistance pattern to other neonicotinoids and fitness were analyzed. The cross-resistance results showed the thiamethoxam-resistant strain had extremely high levels of cross-resistance against clothianidin (>311.7-fold) and nitenpyram (299.9-fold), high levels of cross-resistance against dinotefuran (142.3-fold) and acetamiprid (76.6-fold), and low cross-resistance against imidacloprid (9.3-fold). Compared with the life table of susceptible strain, the thiamethoxam-resistant strain had a relative fitness of 0.950, with significant decreases in oviposition days and fecundity and prolonged developmental duration. The molecular mechanism for fitness costs was studied by comparing the mRNA expression levels of juvenile hormone acid O-methyltransferase (JHAMT), juvenile hormone-binding protein (JHBP), juvenile hormone epoxide hydrolase (JHEH), ecdysone receptor (EcR), ultraspiracle protein (USP), and Vitellogenin (Vg) in the susceptible and thiamethoxam-resistant strains. Significant overexpression of JHEH and JHBP and downregulation of EcR and Vg expression were found in the thiamethoxam-resistant strain. These results indicate that A. gossypii has the potential to develop extremely high resistance to thiamethoxam after continuous exposure, with a considerable fitness cost and cross-resistance to other neonicotinoids.
ESTHER : Zhang_2020_J.Econ.Entomol__
PubMedSearch : Zhang_2020_J.Econ.Entomol__
PubMedID: 32372079

Title : Propoxur resistance associated with insensitivity of acetylcholinesterase (AChE) in the housefly, Musca domestica (Diptera: Muscidae) - You_2020_Sci.Rep_10_8400
Author(s) : You C , Shan C , Xin J , Li J , Ma Z , Zhang Y , Zeng X , Gao X
Ref : Sci Rep , 10 :8400 , 2020
Abstract : Two unique housefly strains, PSS and N-PRS (near-isogenic line with the PSS), were used to clarify the mechanisms associated with propoxur resistance in the housefly, Musca domestica. The propoxur-selected resistant (N-PRS) strain exhibited >1035-fold resistance to propoxur and 1.70-, 12.06-, 4.28-, 57.76-, and 57.54-fold cross-resistance to beta-cypermethrin, deltamethrin, bifenthrin, phoxim, and azamethiphos, respectively, compared to the susceptible (PSS) strain. We purified acetylcholinesterase (AChE) from the N-PRS and PSS strains using a procainamide affinity column and characterized the AChE. The sensitivity of AChE to propoxur based on the bimolecular rate constant (Ki) was approximately 100-fold higher in the PSS strain compared to the N-PRS strain. The cDNA encoding Mdace from both the N-PRS strain and the PSS strain were cloned and sequenced using RT-PCR. The cDNA was 2073 nucleotides long and encoded a protein of 691 amino acids. A total of four single nucleotide polymorphisms (SNPs), I162M, V260L, G342A, and F407Y, were present in the region of the active site of AChE from the N-PRS strain. The transcription level and DNA copy number of Mdace were significantly higher in the resistant strain than in the susceptible strain. These results indicated that mutations combined with the up-regulation of Mdace might be essential in the housefly resistance to propoxur.
ESTHER : You_2020_Sci.Rep_10_8400
PubMedSearch : You_2020_Sci.Rep_10_8400
PubMedID: 32439946

Title : Overexpression of multiple cytochrome P450 genes associated with sulfoxaflor resistance in Aphis gossypii Glover - Ma_2019_Pestic.Biochem.Physiol_157_204
Author(s) : Ma K , Tang Q , Zhang B , Liang P , Wang B , Gao X
Ref : Pestic Biochem Physiol , 157 :204 , 2019
Abstract : Sulfoxaflor is the first commercially available sulfoximine insecticide, which exhibits highly efficacy against many sap-feeding insect pests and has been applied as an alternative insecticide against cotton aphid in China. This study was conducted to investigate the risk of resistance development, the cross-resistance pattern and the potential resistance mechanisms of sulfoxaflor in Aphis gossypii. A colony (SulR strain) of A. gossypii with 245-fold resistance, originated from Xinjiang field population, was established by continuous selection using sulfoxaflor. The SulR strain has developed cross-resistance to imidacloprid (80.8-fold), acetamiprid (19.3-fold), thiamethoxam (10.0-fold), and flupyradifurone (107.5-fold), while no cross-resistance was detected to malathion, omethoate, bifenthrin, methomyl, and carbosulfan. Piperonyl butoxide and S, S, S-tributyl phosphorotrithioate could significantly increase the toxicity of sulfoxaflor to the SulR strain by 5.99- and 4.18-fold, respectively, whereas no synergistic effect with diethyl maleate was observed. The activities of P450s and carboxylesterase were significantly higher in the SulR strain than that in the SS strain. Further gene expression determination demonstrated that nine P450 genes were significantly increased in SulR strain and suppression the expression of CYP6CY13 and CYP6CY19 by RNAi significantly increased the susceptibility of SulR adult aphids to sulfoxaflor. These results demonstrated that the enhancing detoxification by cytochrome P450 monooxygenase may be involved in A.gossypii resistance to sulfoxaflor.
ESTHER : Ma_2019_Pestic.Biochem.Physiol_157_204
PubMedSearch : Ma_2019_Pestic.Biochem.Physiol_157_204
PubMedID: 31153470

Title : Kinetic model of the enzymatic Michael addition for synthesis of mitomycin analogs catalyzed by immobilized lipase from T. laibacchii - Zhang_2019_Mol.Catal_466_146
Author(s) : Zhang Y , Zhao Y , Gao X , Jiang W , Li Z , Yao Q , Yang F , Wang F , Liu J
Ref : Molecular Catalysis , 466 :146 , 2019
Abstract : The present study investigates the kinetic model of the enzymatic Michael addition of butylamine to 2-methyl-1,4-benzoquinone to form 2-methyl-3-n-butylaminoyl-1-hydro-4-quinone in citrate buffer solution (pH 7.0). The yield of the product of 98% was achieved, mainly due to the excellent regioselectivity of immobilized lipase from T. laibacchii. The immobilized preparation used here was obtained by a method of purification and in situ immobilization. Through the purification using a PEG 4000/ K2HPO4 aqueous two-phase system (ATPS), the T. laibacchii lipase was partitioned predominantly in the PEG-rich top phase where diatomite was added to achieve in situ immobilization via interfacial activation on the hydrophobic support. A proposed reaction mechanism of the Michael addition involves (1) the oxyanion hole polarizes the alpha,beta-unsaturated carbonyl of 2-methyl-1,4 -benzoquinone, increasing its electrophilic ability, (2) the catalytic histidine deprotonates the nucleophile n-butyl amine. A modified sequential mechanism including ordered and random sequential bi-bi was proposed for the first, and it is beneficial to add these modification mechanisms to the family of enzyme complex reaction mechanism because the mechanism is partly expanded. The kinetic parameters were directly obtained by combining the numerical integration toolbox ode45 to solve differential equations and the nonlinear optimization toolbox fmincon for error minimizing objective function. A very satisfactory agreement between experimental data and model results was obtained based on the modified random bi-bi mechanism, implying that the enzymatic Michael addition may follow the modified random bi-bi mechanism. The mass transfer limitations were investigated, and it is found that both internal and external mass transfer limitations could be ignored.
ESTHER : Zhang_2019_Mol.Catal_466_146
PubMedSearch : Zhang_2019_Mol.Catal_466_146

Title : A Review of Danshen Combined with Clopidogrel in the Treatment of Coronary Heart Disease - Zhang_2019_Evid.Based.Complement.Alternat.Med_2019_2721413
Author(s) : Zhang Z , Wang Y , Tan W , Wang S , Liu J , Liu X , Wang X , Gao X
Ref : Evid Based Complement Alternat Med , 2019 :2721413 , 2019
Abstract : Objective: Danshen, the root of Salvia miltiorrhiza Bunge, is a traditional herbal medicine in China, which has been used to treat irregular menstruation, cold hernia, and abdominal pain for thousands of years. Danshen is frequently used in combination with drugs to treat cardiovascular diseases. Clopidogrel is a commonly used drug for treating coronary heart disease, but clopidogrel resistance restricts its development. Therefore, the clinical efficacy of Danshen combined with clopidogrel treats coronary heart disease and the relationship between Danshen and clopidogrel metabolism enzymes is suggested for future investigations. Materials and Methods: The information was collected by searching online databases, and the RevMan 5.3 software was used to perform meta-analysis. Results: Twenty-two articles, including 2587 patients, were enrolled after the evaluation. Meta-analysis showed that Danshen combined with clopidogrel was more effective than clopidogrel alone in treating coronary heart disease by improving clinical curative effect, reducing the frequency of angina pectoris, improving electrocardiogram results, shortening the duration of angina pectoris, and easing adverse reactions. Danshen inhibited carboxylesterase 1 and most enzyme of cytochrome P450, especially cytochrome P450 1A2, which may affect the metabolism of clopidogrel. Conclusion: Danshen combined with clopidogrel may compensate for individual differences of clopidogrel resistance among individuals in the treatment of coronary heart disease. Meanwhile, the inhibitory effect of Danshen on cytochrome P450 and carboxylesterase 1 could be partly responsible for the synergistic and attenuating effects of Danshen combined with clopidogrel.
ESTHER : Zhang_2019_Evid.Based.Complement.Alternat.Med_2019_2721413
PubMedSearch : Zhang_2019_Evid.Based.Complement.Alternat.Med_2019_2721413
PubMedID: 30911318

Title : Structure-activity relationship investigation of tertiary amine derivatives of cinnamic acid as acetylcholinesterase and butyrylcholinesterase inhibitors: compared with that of phenylpropionic acid, sorbic acid and hexanoic acid - Gao_2018_J.Enzyme.Inhib.Med.Chem_33_519
Author(s) : Gao X , Tang J , Liu H , Liu L , Kang L , Chen W
Ref : J Enzyme Inhib Med Chem , 33 :519 , 2018
Abstract : In the present investigation, 48 new tertiary amine derivatives of cinnamic acid, phenylpropionic acid, sorbic acid and hexanoic acid (4d-6g, 10d-12g, 16d-18g and 22d-24g) were designed, synthesized and evaluated for the effect on AChE and BChE in vitro. The results revealed that the alteration of aminoalkyl types and substituted positions markedly influences the effects in inhibiting AChE. Almost of all cinnamic acid derivatives had the most potent inhibitory activity than that of other acid derivatives with the same aminoalkyl side chain. Unsaturated bond and benzene ring in cinnamic acid scaffold seems important for the inhibitory activity against AChE. Among them, compound 6g revealed the most potent AChE inhibitory activity (IC50 value: 3.64 micromol/L) and highest selectivity over BChE (ratio: 28.6). Enzyme kinetic study showed that it present a mixed-type inhibition against AChE. The molecular docking study suggested that it can bind with the catalytic site and peripheral site of AChE.
ESTHER : Gao_2018_J.Enzyme.Inhib.Med.Chem_33_519
PubMedSearch : Gao_2018_J.Enzyme.Inhib.Med.Chem_33_519
PubMedID: 29447012

Title : (-)Epigallocatechin-3-gallate attenuates anesthesiainduced memory deficit in young mice via modulation of nitric oxide expression - Ding_2018_Mol.Med.Rep_18_4813
Author(s) : Ding L , Gao X , Hu J , Yu S
Ref : Mol Med Rep , 18 :4813 , 2018
Abstract : (-)Epigallocatechin-3gallate- (EGCG) is a type of polyphenol monomer and is the predominant component of catechin compounds extractable from green tea. Previous studies have demonstrated that EGCG exhibits numerous bioactivities both in vitro and in vivo, including antitumor, antioxidant and antiinflammatory activities, as well as lowering blood lipid levels and protecting against radiation. The present study aimed to investigate whether administration of EGCG may attenuate anesthesiainduced memory deficit in young mice and to reveal the associated underlying mechanisms. The present study revealed that EGCG administration significantly attenuated memory deficit, oxidative stress and cell apoptosis exhibited by anesthesiainduced mice, as determined by Morris water maze testing and ELISA analysis. Furthermore, the results of ELISA and western blot analysis demonstrated that EGCG administration restored acetylcholinesterase activity and modulated the expression levels of neuronal nitric oxide synthase (nNOS), betaamyloid and amyloid precursor protein in anesthesiainduced mice. The present study also employed Larginine as an nNOS substrate and 7nitroindazole as an nNOS inhibitor, which were demonstrated to inhibit or potentiate the effects of EGCG, respectively, on anesthesiainduced memory deficit in mice. Therefore, the present study demonstrated that the administration of EGCG attenuated anesthesiainduced memory deficit in young mice, potentially via the modulation of nitric oxide expression and oxidative stress.
ESTHER : Ding_2018_Mol.Med.Rep_18_4813
PubMedSearch : Ding_2018_Mol.Med.Rep_18_4813
PubMedID: 30320383

Title : De novo transcriptomic analysis of the alimentary tract of the tephritid gall fly, Procecidochares utilis - Li_2018_PLoS.One_13_e0201679
Author(s) : Li L , Lan M , Lu W , Li Z , Xia T , Zhu J , Ye M , Gao X , Wu G
Ref : PLoS ONE , 13 :e0201679 , 2018
Abstract : The tephritid gall fly, Procecidochares utilis, is an important obligate parasitic insect of the malignant weed Eupatorium adenophorum which biosynthesizes toxic secondary metabolites. Insect alimentary tracts secrete several enzymes that are used for detoxification, including cytochrome P450s, glutathione S-transferases, and carboxylesterases. To explore the adaptation of P. utilis to its toxic host plant, E. adenophorum at molecular level, we sequenced the transcriptome of the alimentary tract of P. utilis using Illumina sequencing. Sequencing and de novo assembly yielded 62,443 high-quality contigs with an average length of 604 bp that were further assembled into 45,985 unigenes with an average length of 674 bp and an N50 of 983 bp. Among the unigenes, 30,430 (66.17%) were annotated by alignment against the NCBI non-redundant protein (Nr) database, while 16,700 (36.32%), 16,267 (35.37%), and 11,530 (25.07%) were assigned functions using the Clusters of Orthologous Groups (COG), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Ontology (GO) databases, respectively. Using the comprehensive transcriptome data set, we manually identified several important gene families likely to be involved in the detoxification of toxic compounds including 21 unigenes within the glutathione S-transferase (GST) family, 22 unigenes within the cytochrome P450 (P450) family, and 16 unigenes within the carboxylesterase (CarE) family. Quantitative PCR was used to verify eight, six, and two genes of GSTs, P450s, and CarEs, respectively, in different P. utilis tissues and at different developmental stages. The detoxification enzyme genes were mainly expressed in the foregut and midgut. Moreover, the unigenes were higher expressed in the larvae, pupae, and 3-day adults, while they were expressed at lower levels in eggs. These transcriptomic data provide a valuable molecular resource for better understanding the function of the P. utilis alimentary canal. These identified genes could be pinpoints to address the molecular mechanisms of P. utilis interacting with toxic plant host.
ESTHER : Li_2018_PLoS.One_13_e0201679
PubMedSearch : Li_2018_PLoS.One_13_e0201679
PubMedID: 30138350

Title : Lipase-mediated direct in situ ring-opening polymerization of E-caprolactone formed by a chemo-enzymatic method - Zhang_2018_J.Biotechnol_281_74
Author(s) : Zhang Y , Lu P , Sun Q , Li T , Zhao L , Gao X , Wang F , Liu J
Ref : J Biotechnol , 281 :74 , 2018
Abstract : A novel method to synthesize poly(sigma-caprolactone) (PCL) through a three-step, lipase-mediated chemo-enzymatic reaction from cyclohexanone using an immobilized lipase from Trichosporon laibacchii (T. laibacchii) CBS5791 was developed. The immobilized preparation with 1280 U. g(-1) used here was obtained by a method of purification and in situ immobilization where the crude intracellular lipase (cell homogenate) was subjected to partial purification by an aqueous two-phase system (ATPS) consisting of 12% (w/w) polyethylene glycol (PEG) 4000 and 13% (w/w) potassium phosphate (K(2)HPO(4)) and then in situ immobilization directly on diatomite from the top PEG-rich phase of ATPS. In this multi-step process, the sigma-caprolactone (sigma-CL) produced by lipase-mediated one-pot two-step chemo-enzymatic oxidation of cyclohexanone was directly subjected to in situ ring-opening polymerization (ROP) started by adding highly hydrophobic solvents. It is necessary to note that sigma-CL synthesis and its subsequent ROP were catalyzed by the same lipase. The impact of various reaction parameters, e.g., solvent, cyclohexanone: hydrogen peroxide molar ratio, hydrogen peroxide forms and reaction temperature were investigated. Toluene was selected as a preferred solvent due to supporting the highest molecular weight (M(n) = 2168) and moderate sigma-CL conversion (65.42%). Through the optimization of reaction conditions, PCL was produced with a M(n) of 2283 at 50 degreesC for 24 h. These results reveal that this lipase-mediated direct ring-opening polymerization of in situ formed sigma-CL is an alternative route to the conventional synthesis of PCL.
ESTHER : Zhang_2018_J.Biotechnol_281_74
PubMedSearch : Zhang_2018_J.Biotechnol_281_74
PubMedID: 29908204

Title : Multiple mutations and overexpression of the MdaE7 carboxylesterase gene associated with male-linked malathion resistance in housefly, Musca domestica (Diptera: Muscidae) - Zhang_2018_Sci.Rep_8_224
Author(s) : Zhang Y , Li J , Ma Z , Shan C , Gao X
Ref : Sci Rep , 8 :224 , 2018
Abstract : Two unique housefly strains, MSS and N-MRS, were selected and used to clarify mechanisms of sex-associated malathion resistance in the housefly, Musca domestica. Compared with the lab-susceptible CSS strain, susceptible females and resistant males were observed in the malathion-susceptible MSS strain, while the malathion-resistant near-isogenic line, N-MRS, achieved similar resistance level between genders. Significant synergistic effect of the esterase-inhibitor DEF on resistant houseflies pointed to the important involvement of esterase in this specific malathion resistance. Examination of the carboxylesterase gene MdalphaE7 in malathion resistant housefly populations found seven, non-synonymous SNP mutations (Ser(250)-Thr, Trp(251)-Ser, Met(303)-Ile, Leu(354)-Phe, Ser(357)-Leu, Trp(378)-Arg and Ser(383)-Thr), not found in susceptible houseflies, revealing a strong correlation between these mutations and the development of malathion resistance. Further genetic analysis conducted with bioassays by topical application and nucleotide polymorphism detection provided a first line of molecular evidence for a linkage between a male-determining factor and MdalphaE7 gene in the MSS and N-MRS males. This linkage results in a much higher level of malathion resistance for males than females in the MSS strain. Lastly, quantitative real-time PCR showed that MdalphaE7 was over expressed in the resistant strain due to the increased transcription level of mRNA rather than gene duplication.
ESTHER : Zhang_2018_Sci.Rep_8_224
PubMedSearch : Zhang_2018_Sci.Rep_8_224
PubMedID: 29317643
Gene_locus related to this paper: musdo-EST23aes07

Title : A long-acting FGF21 alleviates hepatic steatosis and inflammation in a mouse model of non-alcoholic steatohepatitis partly through an FGF21-adiponectin-IL17A pathway - Bao_2018_Br.J.Pharmacol_175_3379
Author(s) : Bao L , Yin J , Gao W , Wang Q , Yao W , Gao X
Ref : British Journal of Pharmacology , 175 :3379 , 2018
Abstract : BACKGROUND AND PURPOSE: Non-alcoholic steatohepatitis (NASH) is the most severe form of non-alcoholic fatty liver disease and is a serious public health problem around the world. There are currently no approved treatments for NASH. FGF21 has recently emerged as a promising drug candidate for metabolic diseases. However, the disadvantages of FGF21 as a clinically useful medicine include its short plasma half-life and poor drug-like properties. Here, we have explored the effects of PsTag600-FGF21, an engineered long-acting FGF21 fusion protein, in mice with NASH and describe some of the underlying mechanisms. EXPERIMENTAL APPROACH: A long-acting FGF21 was prepared by genetic fusion with a 600 residues polypeptide (PsTag600). We used a choline-deficient high-fat diet-induced model of NASH in mice. The effects on body weight, insulin sensitivity, inflammation and levels of hormones and metabolites were studied first. We further investigated whether PsTag600-FGF21 attenuated inflammation through the Th17-IL17A axis and the associated mechanisms. KEY RESULTS: PsTag600-FGF21 dose-dependently reduced body weight, blood glucose, and insulin and lipid levels and reversed hepatic steatosis. PsTag600-FGF21 enhanced fatty acid activation and mitochondrial beta-oxidation in the liver. The profound reduction in hepatic inflammation in NASH mice following PsTag600-FGF21 was associated with inhibition of IL17A expression in Th17 cells. Furthermore, PsTag600-FGF21 depended on adiponectin to exert its suppression of Th17 cell differentiation and IL17A expression. CONCLUSIONS AND IMPLICATIONS: Our data have uncovered some of the mechanisms by which PsTag600-FGF21 suppresses hepatic inflammation and further suggest that PsTag600-FGF21 could be an effective approach in NASH treatment.
ESTHER : Bao_2018_Br.J.Pharmacol_175_3379
PubMedSearch : Bao_2018_Br.J.Pharmacol_175_3379
PubMedID: 29859019

Title : Lighting-up breast cancer cells by a near-infrared fluorescent probe based on KIAA1363 enzyme-targeting - Fan_2017_Chem.Commun.(Camb)_53_4857
Author(s) : Fan J , Guo S , Wang S , Kang Y , Yao Q , Wang J , Gao X , Wang H , Du J , Peng X
Ref : Chem Commun (Camb) , 53 :4857 , 2017
Abstract : The first NIR KIAA1363-targeting probe, NB-AX, specifically and instantly featured an "off-on" switch upon gradual addition of KIAA1363 over all kinds of other biomolecules, and its detection limit was initially calculated to be 0.58 mug mL(-1) (3delta/k). The probe was also able to be used in ultrafast distinguishing of breast cancer cells from normal cells in fluorescence imaging and applied in tissue imaging and tumor imaging in vivo.
ESTHER : Fan_2017_Chem.Commun.(Camb)_53_4857
PubMedSearch : Fan_2017_Chem.Commun.(Camb)_53_4857
PubMedID: 28421217
Gene_locus related to this paper: human-NCEH1

Title : Human Neutralizing Monoclonal Antibody Inhibition of Middle East Respiratory Syndrome Coronavirus Replication in the Common Marmoset - Chen_2017_J.Infect.Dis_215_1807
Author(s) : Chen Z , Bao L , Chen C , Zou T , Xue Y , Li F , Lv Q , Gu S , Gao X , Cui S , Wang J , Qin C , Jin Q
Ref : J Infect Dis , 215 :1807 , 2017
Abstract : Middle East respiratory syndrome coronavirus (MERS-CoV) infection in humans is highly lethal, with a fatality rate of 35%. New prophylactic and therapeutic strategies to combat human infections are urgently needed. We isolated a fully human neutralizing antibody, MCA1, from a human survivor. The antibody recognizes the receptor-binding domain of MERS-CoV S glycoprotein and interferes with the interaction between viral S and the human cellular receptor human dipeptidyl peptidase 4 (DPP4). To our knowledge, this study is the first to report a human neutralizing monoclonal antibody that completely inhibits MERS-CoV replication in common marmosets. Monotherapy with MCA1 represents a potential alternative treatment for human infections with MERS-CoV worthy of evaluation in clinical settings.
ESTHER : Chen_2017_J.Infect.Dis_215_1807
PubMedSearch : Chen_2017_J.Infect.Dis_215_1807
PubMedID: 28472421

Title : Inheritance mode and mechanisms of resistance to imidacloprid in the house fly Musca domestica (Diptera:Muscidae) from China - Ma_2017_PLoS.One_12_e0189343
Author(s) : Ma Z , Li J , Zhang Y , Shan C , Gao X
Ref : PLoS ONE , 12 :e0189343 , 2017
Abstract : Imidacloprid is a neonicotinoid insecticide that is effective against house fly, Musca domestica L., which is a major pest with the ability to develop resistance to insecticides. In the present study, we investigated the inheritance mode, the cross-resistance pattern and the mechanisms of resistance to imidacloprid. A near-isogenic house fly line (N-IRS) with 78-fold resistance to imidacloprid was used to demonstrate the mode of inheritance. The overlapping confidence limits of LC50 values and the slopes of the log concentration-probit lines between the reciprocal F1 and F1' progenies suggest that imidacloprid resistance is inherited autosomally in the house fly. There was incomplete dominant inheritance in the F1 and F1' progenies, based on dominance values of 0.77 and 0.75, respectively. A monogenic inheritance model revealed that imidacloprid resistance is governed by more than one factor. Compared to the field strain (CFD), the N-IRS strain developed more cross-resistance to chlorfenapyr and no cross-resistance to chlorpyrifos and acetamiprid, but showed negative cross-resistance to beta-cypermethrin and azamethiphos. Three synergists, diethyl malate (DEM), s,s,s-tributylphosphorotrithioate (DEF), and piperonyl butoxide (PBO), showed significant synergism against to imidacloprid (4.55-, 4.46- and 3.34-fold respectively) in the N-IRS strain. However, both DEM and PBO had no synergism and DEF only exhibited slight synergism in the CSS strain. The activities of carboxylesterase (CarE), glutathione S-transferases (GSTs) and cytochrome P450 in the N-IRS strain were significantly higher than in the CSS strain. But similar synergistic potential of DEF to imidacloprid between the CSS and N-IRS strain suggested that GSTs and cytochrome P450 played much more important role than esterase for the N-IRS strain resistance to imidacloprid. These results should be helpful for developing an improved management strategy to delay the development of imidacloprid resistance in house fly.
ESTHER : Ma_2017_PLoS.One_12_e0189343
PubMedSearch : Ma_2017_PLoS.One_12_e0189343
PubMedID: 29228021

Title : Elevated carboxylesterase activity contributes to the lambda-cyhalothrin insensitivity in quercetin fed Helicoverpa armigera (Hubner) - Chen_2017_PLoS.One_12_e0183111
Author(s) : Chen C , Liu Y , Shi X , Desneux N , Han P , Gao X
Ref : PLoS ONE , 12 :e0183111 , 2017
Abstract : Quercetin as one of the key plant secondary metabolite flavonol is ubiquitous in terrestrial plants. In this study, the decrease in sensitivity to lambda-cyhalothrin was observed in quercetin-fed Helicoverpa armigera larvae. In order to figure out the mechanisms underlying the decreased sensitivity of H. armigera larvae to lambda-cyhalothrin by quercetin induction, the changes in carboxylesterase activity and in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin were examined. The LC50 value of quercetin-fed H. armigera larvae to lambda-cyhalothrin showed 2.41-fold higher than that of the control. S, S, S-Tributyl phosphorotrithioate (DEF) treatment showed a synergism effect on lambda-cyhalothrin toxicity to quercetin-fed H. armigera. Moreover, the activity of carboxylesterase was significantly higher in quercetin-fed H. armigera larvae after fed on quercetin for 48 h. The in-vitro hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera larvae midgut was 289.82 nmol 3-PBA/mg protein/min, which is significant higher than that in the control group (149.60 nmol 3-PBA/mg protein/min). The elevated CarE enzyme activity and corresponding increased hydrolytic metabolic capacity to lambda-cyhalothrin in quercetin-fed H. armigera contributed to the enhanced tolerance to lambda-cyhalothrin.
ESTHER : Chen_2017_PLoS.One_12_e0183111
PubMedSearch : Chen_2017_PLoS.One_12_e0183111
PubMedID: 28817718

Title : Red Blood Cell Distribution Width to Platelet Ratio is Related to Histologic Severity of Primary Biliary Cirrhosis - Wang_2016_Medicine.(Baltimore)_95_e3114
Author(s) : Wang H , Xu H , Wang X , Wu R , Gao X , Jin Q , Niu J
Ref : Medicine (Baltimore) , 95 :e3114 , 2016
Abstract : We aimed to investigate whether red blood cell distribution width (RDW) and RDW to platelet ratio (RPR) were related to the histologic severity of primary biliary cirrhosis (PBC).Seventy-three treatment-naive PBC patients who had undergone a liver biopsy between January 2010 and January 2015 were enrolled in our study. The patients' histological stages were based on the classifications of Ludwig and Scheuer. The patients were divided into early stage (Stage I) and advanced stage (Stage II, III, and IV) hepatic fibrosis according to their histological stage. All common patient demographics, clinical characteristics, hematological parameters, liver biochemistry, and antimitochondrial M2 antibody levels (AMA-M2) were retrospectively analyzed, and RDW, RPR, aspartate aminotransferase-to-platelet ratio index (APRI), and fibrosis index based on the 4 factors (FIB-4) were calculated.A total of 28 (38.4%) patients had early stage PBC, whereas 45 (62.6%) were classified as advanced stage. Regarding age, no significant differences between the early and advanced stages were observed. Patients with advanced stage PBC had significantly higher RDW (13.6 vs 14.4; P = 0.019), conjugated bilirubin (10.1 vs 23.4; P = 0.029), and significantly lower cholinesterase (7901.1 vs 6060.8; P = 0.001) and platelets (212.6 vs 167.0; P = 0.006). However, no significant differences (P > 0.05) in other routine parameters previously evaluated in PBC, including aspartate aminotransferase (AST) and mean platelet volume, were found between the groups. The sensitivity and specificity of RDW were 33.3% and 92.9%, respectively, and the area under the receiver-operating characteristic curve (AUROC) was 0.66. However, the sensitivity and specificity of RPR were 46.7% and 96.4%, respectively, and the corresponding AUROC was 0.74 (P < 0.001). Hence, compared with preexisting indicators, RPR showed a higher AUROC than APRI (0.648; P = 0.035) and FIB-4 (0.682; P = 0.009).RDW and RPR may be a new noninvasive marker for predicting histologic severity of PBC.
ESTHER : Wang_2016_Medicine.(Baltimore)_95_e3114
PubMedSearch : Wang_2016_Medicine.(Baltimore)_95_e3114
PubMedID: 26986159

Title : Effects of spirotetramat treatments on fecundity and carboxylesterase expression of Aphis gossypii Glover - Gong_2016_Ecotoxicology_25_655
Author(s) : Gong Y , Shi X , Desneux N , Gao X
Ref : Ecotoxicology , 25 :655 , 2016
Abstract : Spirotetramat is a novel tetramic acid-based insecticide, belonging to keto-enol pesticide family, with a novel mode of action; it interferes with lipid biosynthesis. Its insecticide activity against various agricultural pest insects have been demonstrated (e.g. on Myzus persicae, Bemisia tabaci and Tetranychus urticae). However, information available is currently limited on the efficacy of spirotetramat on the cotton aphid, Aphis gossypii, a key cotton pest worldwide. We assessed the spirotetramat toxicity on A. gossypii and evaluated its effects on aphid fecundity when exposed to a sublethal concentration (LC10) and to increasing lethal concentrations (LC25, LC50, and LC75). A key mechanism involved in insecticide resistance in aphids relates to esterase activity. We estimated the CarE activity and a CarE gene expression in aphids in response to spirotetramat exposure, then we tested tolerance of offspring to spirotetramat when the parents were exposed to the highest concentration tested in our study (LC75). Results showed that spirotetramat showed increasing toxicity to A. gossypii with exposure duration to treated leaves; LC50 ranged from 23,675.68 to 12.27 mg/L for 1 to 5-days exposure. In addition, spirotetramat reduced aphid daily fecundity, in all concentration treatments, especially with up to 90 % reduction in case of exposure to LC75. Total CarE activity increased dramatically and CarE mRNA expression was also up regulated in aphids after exposure to LC75 spirotetramat. Finally, the tolerance to spirotetramat in offspring (when parents were exposed to the LC75) showed a 2.5-fold increase when compared to control aphids. Consequently, spiroteramat showed potential for pest management of cotton aphids owing to both lethal and sublethal activities, notably strong impact on aphid fecundity. However, we also demonstrated that increased tolerance of A. gossypii to spirotetramat may happen through increased CarE- activity and subsequent metabolic degradation of the insecticide in aphids' body.
ESTHER : Gong_2016_Ecotoxicology_25_655
PubMedSearch : Gong_2016_Ecotoxicology_25_655
PubMedID: 26898726

Title : CLD1 Reverses the Ubiquinone Insufficiency of Mutant cat5\/coq7 in a Saccharomyces cerevisiae Model System - Kar_2016_PLoS.One_11_e0162165
Author(s) : Kar A , Beam H , Borror MB , Luckow M , Gao X , Rea SL
Ref : PLoS ONE , 11 :e0162165 , 2016
Abstract : Ubiquinone (Qn) functions as a mobile electron carrier in mitochondria. In humans, Q biosynthetic pathway mutations lead to Q10 deficiency, a life threatening disorder. We have used a Saccharomyces cerevisiae model of Q6 deficiency to screen for new modulators of ubiquinone biosynthesis. We generated several hypomorphic alleles of coq7/cat5 (clk-1 in Caenorhabditis elegans) encoding the penultimate enzyme in Q biosynthesis which converts 5-demethoxy Q6 (DMQ6) to 5-demethyl Q6, and screened for genes that, when overexpressed, suppressed their inability to grow on non-fermentable ethanol-implying recovery of lost mitochondrial function. Through this approach we identified Cardiolipin-specific Deacylase 1 (CLD1), a gene encoding a phospholipase A2 required for cardiolipin acyl remodeling. Interestingly, not all coq7 mutants were suppressed by Cld1p overexpression, and molecular modeling of the mutant Coq7p proteins that were suppressed showed they all contained disruptions in a hydrophobic alpha-helix that is predicted to mediate membrane-binding. CLD1 overexpression in the suppressible coq7 mutants restored the ratio of DMQ6 to Q6 toward wild type levels, suggesting recovery of lost Coq7p function. Identification of a spontaneous Cld1p loss-of-function mutation illustrated that Cld1p activity was required for coq7 suppression. This observation was further supported by HPLC-ESI-MS/MS profiling of monolysocardiolipin, the product of Cld1p. In summary, our results present a novel example of a lipid remodeling enzyme reversing a mitochondrial ubiquinone insufficiency by facilitating recovery of hypomorphic enzymatic function.
ESTHER : Kar_2016_PLoS.One_11_e0162165
PubMedSearch : Kar_2016_PLoS.One_11_e0162165
PubMedID: 27603010
Gene_locus related to this paper: yeast-cld1

Title : Survey of organophosphate resistance and an Ala216Ser substitution of acetylcholinesterase-1 gene associated with chlorpyrifos resistance in Apolygus lucorum (Meyer-Dur) collected from the transgenic Bt cotton fields in China - Zhen_2016_Pestic.Biochem.Physiol_132_29
Author(s) : Zhen C , Miao L , Liang P , Gao X
Ref : Pestic Biochem Physiol , 132 :29 , 2016
Abstract : The mirid bug is frequently controlled by the application of organophosphorus insecticides in the transgenic Bt cotton field of China. A topical bioassay method was performed to evaluate the toxicities of chlorpyrifos and malathion towards field-collected Chinese populations of Apolygus lucorum from transgenic Bt cotton fields. For chlorpyrifos, the resistance ratios ranged from 0.8 to 9.4-fold compared to a susceptible strain. For malathion, the resistance levels relative to the susceptible strain ranged from 1.2 to 14.4-fold. Compared to a susceptible strain, the Cangzhou population from Hebei province showed the highest resistance ratios towards these insecticides. A comparison of the detoxifying and target enzyme activities between the Cangzhou population and a susceptible strain revealed that altered acetylcholinesterase possibly account for the chlorpyrifos and malathion resistance in the Cangzhou population. Two acetylcholinesterase (AChE-encoding) genes (designated Alace1 and Alace2) from the green mirid bug (A. lucorum) were identified. The Alace1 and Alace2 genes encoded 597 and 645 amino acids, respectively. Both AChE proteins had conserved motifs including a catalytic triad, a choline-binding site, and an acyl pocket. Quantitative real-time PCR analysis showed that Alace1 had a much higher transcriptional level than Alace2, for the expression profiles of both spatial and time distributions. One amino acid substitution, Ala216Ser in Alace1, was found in the Cangzhou population. These results suggest that the mutation Ala216Ser should be most likely involved in organophosphorus resistance in A. lucorum.
ESTHER : Zhen_2016_Pestic.Biochem.Physiol_132_29
PubMedSearch : Zhen_2016_Pestic.Biochem.Physiol_132_29
PubMedID: 27521910
Gene_locus related to this paper: apolu-ACHE1

Title : Novel ferulic amide derivatives with tertiary amine side chain as acetylcholinesterase and butyrylcholinesterase inhibitors: The influence of carbon spacer length, alkylamine and aromatic group - Liu_2016_Eur.J.Med.Chem_126_810
Author(s) : Liu H , Liu L , Gao X , Liu Y , Xu W , He W , Jiang H , Tang J , Fan H , Xia X
Ref : Eur Journal of Medicinal Chemistry , 126 :810 , 2016
Abstract : Based on our recent investigations on chalcone derivatives as AChE inhibitors, a series of ferulic acid (FA) tertiary amine derivatives similar to chalcone compounds were designed and synthesized. The results of bioactivity evaluation revealed that most of new synthesized compounds had comparable or more potent AChE inhibitory activity than the control drug Rivastigmine. The alteration of carbon chain linking tertiary amine groups and ferulic acid scaffold markedly influenced the inhibition activity against AChE. Among them the inhibitory activity of compound 6d (IC50: 0.71 +/- 0.09 mumol/L) and 6e (IC50: 1.11 +/- 0.17 mumol/L) was equal to 15-fold and 9-fold than that of Rivastigmine against AChE (IC50: 10.54 +/- 0.86 mumol/L), respectively. Moreover, compound 6d shows the highest selectivity for AChE over butyrylcholinesterase(BuChE) (ratio: 18.3). The kinetic study suggested that compound 6d revealed a mixed-type inhibition against AChE. The result of molecular docking showed that compound 6d combines to AChE with three amino acid sites(Trp84, Tyr334 and Trp279), while combines to BuChE with two amino acid sites (Tyr67 and Gly66) in enzyme domains, respectively. Compound 6d might act as a potential agent for the treatment of Alzheimer's diseases (AD).
ESTHER : Liu_2016_Eur.J.Med.Chem_126_810
PubMedSearch : Liu_2016_Eur.J.Med.Chem_126_810
PubMedID: 27951489

Title : A point mutation (L1015F) of the voltage-sensitive sodium channel gene associated with lambda-cyhalothrin resistance in Apolygus lucorum (Meyer-Dur) population from the transgenic Bt cotton field of China - Zhen_2016_Pestic.Biochem.Physiol_127_82
Author(s) : Zhen C , Gao X
Ref : Pestic Biochem Physiol , 127 :82 , 2016
Abstract : In China, the green mirid bug, Apolygus lucorum (Meyer-Dur), has caused severe economic damage to many kinds of crops, especially the cotton and jujubes. Pyrethroid insecticides have been widely used for controlling this pest in the transgenic Bt cotton field. Five populations of A. lucorum collected from cotton crops at different locations in China were evaluated for lambda-cyhalothrin resistance. The results showed that only the population collected from Shandong Province exhibited 30-fold of resistance to lambda-cyhalothrin. Neither PBO nor DEF had obvious synergism when compared the synergistic ratio between SS and RR strain which was originated from the Shandong population. Besides, there were no statistically significant differences (p>0.05) in the carboxylesterase, glutathione S-transferase, or 7-ethoxycoumarin O-deethylase activities between the Shandong population and the laboratory susceptible strain (SS). The full-length sodium channel gene named AlVSSC encoding 2028 amino acids was obtained by RT-PCR and rapid amplification of cDNA ends (RACE). One single point mutation L1015F in the AlVSSC was detected only in the Shandong population. Our results revealed that the L1015F mutation associated with pyrethroid resistance was identified in A. lucorum populations in China. These results will be useful for the rational chemical control of A. lucorum in the transgenic Bt cotton field.
ESTHER : Zhen_2016_Pestic.Biochem.Physiol_127_82
PubMedSearch : Zhen_2016_Pestic.Biochem.Physiol_127_82
PubMedID: 26821662

Title : Perilipin 5 improves hepatic lipotoxicity by inhibiting lipolysis - Wang_2015_Hepatology_61_870
Author(s) : Wang C , Zhao Y , Gao X , Li L , Yuan Y , Liu F , Zhang L , Wu J , Hu P , Zhang X , Gu Y , Xu Y , Wang Z , Li Z , Zhang H , Ye J
Ref : Hepatology , 61 :870 , 2015
Abstract : Abnormal metabolism of nonesterified fatty acids (NEFAs) and their derivatives has been reported to be the main cause of intracellular lipotoxic injury. Normally, NEFAs are stored in lipid droplets (LDs) in the form of triglyceride (TG), which could reduce the lipotoxicity of cytosolic NEFAs. Previous studies have implicated that Perilipin 5 (Plin5), an LD-binding protein, regulates the storage and hydrolysis of TG in LD. However, its roles and underlying mechanisms in the liver remain unknown. Here we found that Plin5 expression was increased in steatotic livers. Using Plin5 knockout mice, we found that Plin5 deficiency resulted in reduced hepatic lipid content and smaller-sized LDs, which was due to the elevated lipolysis rate and fatty acid utilization. Plin5-deficient hepatocytes showed increased mitochondria proliferation, which could be explained by the increased expression and activity of PPARalpha stimulated by the increased NEFA levels. Meanwhile, Plin5-deficient livers also exhibited enhanced mitochondrial oxidative capacity. We also found that Plin5 deficiency induces lipotoxic injury in hepatocytes, attributed to lipid peroxidation. Mechanistically, we found that Plin5 blocks adipose triglyceride lipase (ATGL)-mediated lipolysis by competitively binding to comparative gene identification-58 (CGI-58) and disrupting the interaction between CGI-58 and ATGL. CONCLUSION: Plin5 is an important protective factor against hepatic lipotoxicity induced by NEFAs generated from lipolysis. This provides an important new insight into the regulation of hepatic lipid storage and relation between lipid storage and lipotoxicity.
ESTHER : Wang_2015_Hepatology_61_870
PubMedSearch : Wang_2015_Hepatology_61_870
PubMedID: 25179419

Title : Alteration of osa-miR156e expression affects rice plant architecture and strigolactones (SLs) pathway - Chen_2015_Plant.Cell.Rep_34_767
Author(s) : Chen Z , Gao X , Zhang J
Ref : Plant Cell Rep , 34 :767 , 2015
Abstract : Overexpressing osa--miR156e in rice produced a bushy mutant and osa--miR156e regulation of tillering may do this through the strigolactones (SLs) pathway. Appropriate downregulation of osa--miR156 expression contributed to the improvement of plant architecture. Tillering is one of the main determinants for rice architecture and yield. In this study, a bushy mutant of rice was identified with increased tiller number, reduced plant height, prolonged heading date, low seed setting, and small panicle size due to a T-DNA insertion which essentially elevated the expression of osa-miR156e. Transgenic plants with constitutive expression of osa-miR156e also had the bushy phenotype, which showed osa-miR156 may control apical dominance and tiller outgrowth via regulating the strigolactones signaling pathway. Furthermore, the extent of impaired morphology was correlated with the expression level of osa-miR156e. In an attempt to genetically improve rice architecture, ectopic expression of osa-miR156e under the GAL4-UAS system or OsTB1 promoter was conducted. According to agronomic trait analysis, pTB1:osa-miR156e transgenic plants significantly improved the grain yield per plant compared to plants overexpressing osa-miR156e, even though the yield was still inferior to the wild type, making it a very interesting albeit negative result. Our results suggested that osa-miR156 could serve as a potential tool for modifying rice plant architecture through genetic manipulation of the osa-miR156 expression level.
ESTHER : Chen_2015_Plant.Cell.Rep_34_767
PubMedSearch : Chen_2015_Plant.Cell.Rep_34_767
PubMedID: 25604991

Title : Assessment of Sublethal and Transgenerational Effects of Pirimicarb on the Wheat Aphids Rhopalosiphum padi and Sitobion avenae - Xiao_2015_PLoS.One_10_e0128936
Author(s) : Xiao D , Yang T , Desneux N , Han P , Gao X
Ref : PLoS ONE , 10 :e0128936 , 2015
Abstract : The wheat aphids, Rhopalosiphum padi (Linnaeus) and Sitobion avenae (Fabricius), are key pests on wheat crops worldwide. Management practices rely primarily on insecticides. The pirimicarb (carbamate) is used extensively as an effective insecticide to control these two aphids. In addition to the mortality caused by pirimicarb, various sublethal effects may occur in aphids when exposed to low lethal or sublethal doses. Understanding the general effect of pirimicarb on aphids could help increasing rational use of this insecticide. Under laboratory conditions, we assessed the sublethal effects of a low lethal concentration of pirimicarb (LC25) on biological traits and acetylcholinesterase (AChE) activity of R. padi and S. avenae. Both direct and transgenerational effects, i.e. on parent and the F1 generations were assessed, respectively. We found that R. padi and S. avenae responded differentially to the LC25 of pirimicarb. The parent generation of R. padi showed a 39% decrease in fecundity and multiple transgenerational effects were observed in the F1 generation; overall juvenile development, reproductive period, adult longevity and lifespan were longer than those of the control group. By contrast, LC25 of pirimicarb showed almost no effects on S. avenae biological traits in both the parent and F1 generations; only the pre-reproductive duration was reduced in F1 generations. Demographic parameter estimates (e.g. rm) showed similar trend, i.e. significant negative effect on R. padi population growth and no effect on S. avenae. However, AChE activity decreased in both R. padi and S. avenae treated by the LC25 of pirimicarb. We demonstrated sublethal and transgenerational effects of pirimicarb in the two wheat aphid species; it hinted at the importance of considering sublethal effects (including hormesis) of pirimicarb for optimizing Integrated Pest Management (IPM) of wheat aphids.
ESTHER : Xiao_2015_PLoS.One_10_e0128936
PubMedSearch : Xiao_2015_PLoS.One_10_e0128936
PubMedID: 26121265

Title : Design, synthesis and preliminary structure-activity relationship investigation of nitrogen-containing chalcone derivatives as acetylcholinesterase and butyrylcholinesterase inhibitors: a further study based on Flavokawain B Mannich base derivatives - Liu_2015_J.Enzyme.Inhib.Med.Chem__1
Author(s) : Liu H , Fan H , Gao X , Huang X , Liu X , Liu L , Zhou C , Tang J , Wang Q , Liu W
Ref : J Enzyme Inhib Med Chem , :1 , 2015
Abstract : In order to study the structure-activity relationship of Flavokawain B Mannich-based derivatives as acetylcholinesterase (AChE) inhibitors in our recent investigation, 20 new nitrogen-containing chalcone derivatives (4 a-8d) were designed, synthesized, and evaluated for AChE inhibitory activity in vitro. The results suggested that amino alkyl side chain of chalcone dramatically influenced the inhibitory activity against AChE. Among them, compound 6c revealed the strongest AChE inhibitory activity (IC50 value: 0.85 mumol/L) and the highest selectivity against AChE over BuChE (ratio: 35.79). Enzyme kinetic study showed that the inhibition mechanism of compound 6c against AChE was a mixed-type inhibition. The molecular docking assay showed that this compound can both bind with the catalytic site and the peripheral site of AChE.
ESTHER : Liu_2015_J.Enzyme.Inhib.Med.Chem__1
PubMedSearch : Liu_2015_J.Enzyme.Inhib.Med.Chem__1
PubMedID: 26186269

Title : Transcriptomic comparison of thiamethoxam-resistance adaptation in resistant and susceptible strains of Aphis gossypii Glover - Pan_2014_Comp.Biochem.Physiol.Part.D.Genomics.Proteomics_13C_10
Author(s) : Pan Y , Peng T , Gao X , Zhang L , Yang C , Xi J , Xin X , Bi R , Shang Q
Ref : Comparative Biochemistry & Physiology Part D Genomics Proteomics , 13C :10 , 2014
Abstract : A thiamethoxam-resistant strain of cotton aphid (ThR) strain displayed a 19.35-fold greater resistance to thiamethoxam compared to a susceptible cotton aphid (SS) strain. Solexa sequencing technology was used to investigate differentially expressed genes (DEGs) in cotton aphids in the context of thiamethoxam resistance. A total of 22,569,311 and 21,317,732 clean reads were obtained from the ThR and SS transcriptomes, respectively, and assembled into 35,222 non-redundant (Nr) consensus sequences. The expression of 620 unigenes changed significantly in the ThR libraries compared to the SS strain; 349 genes were up-regulated, and 271 genes were down-regulated (P<=0.001). Expression levels of ribosomal proteins, ATP synthase, cytochrome c oxidase, ecdysteroid UDP-glucosyltransferase and esterase were up-regulated significantly in the ThR strain compared to the SS strain. The genes of cuticle proteins, salivary proteins, and fibroin heavy chain decreased dramatically. One nicotinic acetylcholine receptor (nAChR) alpha subunit was down-regulated in the ThR strain. The expression levels of 10 differentially expressed unigenes were confirmed using real-time RT-PCR, and the observed trends in gene expression matched the Solexa expression profiles. Specific single-nucleotide polymorphisms (SNPs) in nAChRs that cause amino acid substitution were found from the ThR and SS stains respectively. These data illustrate that genetic changes in nAChR genes and up-regulated ribosomal proteins, ecdysteroid UDP-glucosyltransferase, cytochrome c oxidase, esterase and peroxidase may confer the tolerance of resistant cotton aphids to thiamethoxam.
ESTHER : Pan_2014_Comp.Biochem.Physiol.Part.D.Genomics.Proteomics_13C_10
PubMedSearch : Pan_2014_Comp.Biochem.Physiol.Part.D.Genomics.Proteomics_13C_10
PubMedID: 25528611

Title : Huperserines A-E, Lycopodium alkaloids from Huperzia serrata - Jiang_2014_Fitoterapia_99C_72
Author(s) : Jiang WW , Liu F , Gao X , He J , Cheng X , Peng LY , Wu XD , Zhao QS
Ref : Fitoterapia , 99C :72 , 2014
Abstract : A phytochemical study on Huperzia serrata led to the isolation of four new 5-deoxyfawcettimine-related Lycopodium alkaloids, huperserines A-D (1-4), and one new lycodine-type alkaloid, huperserine E (5). Their structures were elucidated based on spectroscopic data, including 1D and 2D NMR techniques. 5-Carbonyl or 5-hydroxyl group is a typical characteristic of lycopodine- and fawcettimine-type alkaloids. This is the first report of the 5-deoxyfawcettimine type Lycopodium alkaloids. In vitro acetylcholinesterase (AChE) inhibitory activity assay showed that huperserine E exhibited moderate anti-AChE activity with an IC50 value of 6.71muM.
ESTHER : Jiang_2014_Fitoterapia_99C_72
PubMedSearch : Jiang_2014_Fitoterapia_99C_72
PubMedID: 25218968

Title : Genome of the human hookworm Necator americanus - Tang_2014_Nat.Genet_46_261
Author(s) : Tang YT , Gao X , Rosa BA , Abubucker S , Hallsworth-Pepin K , Martin J , Tyagi R , Heizer E , Zhang X , Bhonagiri-Palsikar V , Minx P , Warren WC , Wang Q , Zhan B , Hotez PJ , Sternberg PW , Dougall A , Gaze ST , Mulvenna J , Sotillo J , Ranganathan S , Rabelo EM , Wilson RK , Felgner PL , Bethony J , Hawdon JM , Gasser RB , Loukas A , Mitreva M
Ref : Nat Genet , 46 :261 , 2014
Abstract : The hookworm Necator americanus is the predominant soil-transmitted human parasite. Adult worms feed on blood in the small intestine, causing iron-deficiency anemia, malnutrition, growth and development stunting in children, and severe morbidity and mortality during pregnancy in women. We report sequencing and assembly of the N. americanus genome (244 Mb, 19,151 genes). Characterization of this first hookworm genome sequence identified genes orchestrating the hookworm's invasion of the human host, genes involved in blood feeding and development, and genes encoding proteins that represent new potential drug targets against hookworms. N. americanus has undergone a considerable and unique expansion of immunomodulator proteins, some of which we highlight as potential treatments against inflammatory diseases. We also used a protein microarray to demonstrate a postgenomic application of the hookworm genome sequence. This genome provides an invaluable resource to boost ongoing efforts toward fundamental and applied postgenomic research, including the development of new methods to control hookworm and human immunological diseases.
ESTHER : Tang_2014_Nat.Genet_46_261
PubMedSearch : Tang_2014_Nat.Genet_46_261
PubMedID: 24441737
Gene_locus related to this paper: necam-w2tsu7

Title : Duplication of acetylcholinesterase gene in diamondback moth strains with different sensitivities to acephate - Sonoda_2014_Insect.Biochem.Mol.Biol_48_83
Author(s) : Sonoda S , Shi X , Song D , Liang P , Gao X , Zhang Y , Li J , Liu Y , Li M , Matsumura M , Sanada-Morimura S , Minakuchi C , Tanaka T , Miyata T
Ref : Insect Biochemistry & Molecular Biology , 48 :83 , 2014
Abstract : This study examined the acetylcholinesterase 1 gene (AChE1) in Plutella xylostella strains with different sensitivities to acephate. Multiple haplotypes of the gene were found in the field-collected strains including distinct haplotypes carrying one or both previously reported mutations (A298S and G324A). Moreover, sequencing results indicated the presence of duplicated copies of the gene in the field-collected strains. No correlation was found between copy numbers of AChE1 and levels of resistance to acephate suggesting that extensive AChE1 duplication is not a major resistance factor at least in some P. xylostella strains. Proportions of the A298S and G324A mutations showed no correlation with levels of resistance to acephate. This suggests that acephate resistance of P. xylostella is complex and cannot be evaluated based on the AChE1 copy number or proportions of the resistance mutations alone.
ESTHER : Sonoda_2014_Insect.Biochem.Mol.Biol_48_83
PubMedSearch : Sonoda_2014_Insect.Biochem.Mol.Biol_48_83
PubMedID: 24632376

Title : Genomic study of polyhydroxyalkanoates producing Aeromonas hydrophila 4AK4 - Gao_2013_Appl.Microbiol.Biotechnol_97_9099
Author(s) : Gao X , Jian J , Li WJ , Yang YC , Shen XW , Sun ZR , Wu Q , Chen GQ
Ref : Applied Microbiology & Biotechnology , 97 :9099 , 2013
Abstract : The complete genome of Gram-negative Aeromonas hydrophila 4AK4 that has been used for industrial production of poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) was sequenced and annotated. Its chromosome is 4,527,993 bp in size encoding 4,272 genes, including 28 rRNA genes and 104 tRNA genes. Comparative analysis indicated that genome of A. hydrophila 4AK4 was similar to that of the A. hydrophila ATCC 7966(T), an intensively studied aeromonad for its pathogenicity related to its genomic information. Genes possibly coming from other species or even other genus were identified in A. hydrophila 4AK4. A large number of putative virulent genes were predicted. However, a cytotonic enterotoxin (Ast) is absent in A. hydrophila 4AK4, allowing the industrial strain to be different from other A. hydrophila strains, indicating possible reduced virulence of strain 4AK4, which is very important for industrial fermentation. Genes involved in polyhydroxyalkanoate (PHA) metabolism were predicted and analyzed. The resulting genomic information is useful for improved production of PHA via metabolic engineering of A. hydrophila 4AK4.
ESTHER : Gao_2013_Appl.Microbiol.Biotechnol_97_9099
PubMedSearch : Gao_2013_Appl.Microbiol.Biotechnol_97_9099
PubMedID: 24000047
Gene_locus related to this paper: aerme-a0a023rmd0 , aervb-f4dgq1

Title : Lactoferrin-modified PEG-co-PCL nanoparticles for enhanced brain delivery of NAP peptide following intranasal administration - Liu_2013_Biomaterials_34_3870
Author(s) : Liu Z , Jiang M , Kang T , Miao D , Gu G , Song Q , Yao L , Hu Q , Tu Y , Pang Z , Chen H , Jiang X , Gao X , Chen J
Ref : Biomaterials , 34 :3870 , 2013
Abstract : Development of effective non-invasive drug delivery systems is of great importance to the treatment of Alzheimer's diseases and has made great progress in recent years. In this work, lactoferrin (Lf), a natural iron binding protein, whose receptor is highly expressed in both respiratory epithelial cells and neurons is here utilized to facilitate the nose-to-brain drug delivery of neuroprotection peptides. The Lf-conjugated PEG-PCL nanoparticle (Lf-NP) was constructed via a maleimide-thiol reaction with the Lf conjugation confirmed by CBQCA Protein Quantitation and XPS analysis. Other important parameters such as particle size distribution, zeta potential and in vitro release of fluorescent probes were also characterized. Compared with unmodified nanoparticles (NP), Lf-NP exhibited a significantly enhanced cellular accumulation in 16HBE14o-cells through both caveolae-/clathrin-mediated endocytosis and direct translocation. Following intranasal administration, Lf-NP facilitated the brain distribution of the coumarin-6 incorporated with the AUC0-8h in rat cerebrum (with hippocampus removed), cerebellum, olfactory tract, olfactory bulb and hippocampus 1.36, 1.53, 1.70, 1.57 and 1.23 times higher than that of coumarin-6 carried by NP, respectively. Using a neuroprotective peptide - NAPVSIPQ (NAP) as the model drug, the neuroprotective and memory improvement effect of Lf-NP was observed even at lower dose than that of NP in a Morris water maze experiment, which was also confirmed by the evaluation of acetylcholinesterase, choline acetyltransferase activity and neuronal degeneration in the mice hippocampus. In conclusion, Lf-NP may serve as a promising nose-to-brain drug delivery carrier especially for peptides and proteins.
ESTHER : Liu_2013_Biomaterials_34_3870
PubMedSearch : Liu_2013_Biomaterials_34_3870
PubMedID: 23453061

Title : Toxicogenomic studies of human neural cells following exposure to organophosphorus chemical warfare nerve agent VX - Gao_2013_Neurochem.Res_38_916
Author(s) : Gao X , Lin H , Ray R , Ray P
Ref : Neurochem Res , 38 :916 , 2013
Abstract : Organophosphorus (OP) compounds represent an important group of chemical warfare nerve agents that remains a significant and constant military and civilian threat. OP compounds are considered acting primarily via cholinergic pathways by binding irreversibly to acetylcholinesterase, an important regulator of the neurotransmitter acetylcholine. Many studies over the past years have suggested that other mechanisms of OP toxicity exist, which need to be unraveled by a comprehensive and systematic approach such as genome-wide gene expression analysis. Here we performed a microarray study in which cultured human neural cells were exposed to 0.1 or 10 muM of VX for 1 h. Global gene expression changes were analyzed 6, 24, and 72 h post exposure. Functional annotation and pathway analysis of the differentially expressed genes has revealed many genes, networks and canonical pathways that are related to nervous system development and function, or to neurodegenerative diseases such as Alzheimer's disease, Huntington's disease, and Parkinson's disease. In particular, the neuregulin pathway impacted by VX exposure has important implications in many nervous system diseases including schizophrenia. These results provide useful information valuable in developing suitable antidotes for more effective prevention and treatment of, as well as in developing biomarkers for, VX-induced chronic neurotoxicity.
ESTHER : Gao_2013_Neurochem.Res_38_916
PubMedSearch : Gao_2013_Neurochem.Res_38_916
PubMedID: 23440544

Title : Genome organization, phylogenies, expression patterns, and three-dimensional protein models of two acetylcholinesterase genes from the red flour beetle - Lu_2012_PLoS.One_7_e32288
Author(s) : Lu Y , Pang YP , Park Y , Gao X , Yao J , Zhang X , Zhu KY
Ref : PLoS ONE , 7 :e32288 , 2012
Abstract : Since the report of a paralogous acetylcholinesterase (AChE, EC3.1.1.7) gene in the greenbug (Schizaphis graminum) in 2002, two different AChE genes (Ace1 and Ace2) have been identified in each of at least 27 insect species. However, the gene models of Ace1 and Ace2, and their molecular properties have not yet been comprehensively analyzed in any insect species. In this study, we sequenced the full-length cDNAs, computationally predicted the corresponding three-dimensional protein models, and profiled developmental stage and tissue-specific expression patterns of two Ace genes from the red flour beetle (Tribolium castaneum; TcAce1 and TcAce2), a globally distributed major pest of stored grain products and an emerging model organism. TcAce1 and TcAce2 encode 648 and 604 amino acid residues, respectively, and have conserved motifs including a choline-binding site, a catalytic triad, and an acyl pocket. Phylogenetic analysis show that both TcAce genes are grouped into two insect Ace clusters and TcAce1 is completely diverged from TcAce2, suggesting that these two genes evolve from their corresponding Ace gene lineages in insect species. In addition, TcAce1 is located on chromosome 5, whereas TcAce2 is located on chromosome 2. Reverse transcription polymerase chain reaction (PCR) and quantitative real-time PCR analyses indicate that both genes are virtually transcribed in all the developmental stages and predominately expressed in the insect brain. Our computational analyses suggest that the TcAce1 protein is a robust acetylcholine (ACh) hydrolase and has susceptibility to sulfhydryl agents whereas the TcAce2 protein is not a catalytically efficient ACh hydrolase.
ESTHER : Lu_2012_PLoS.One_7_e32288
PubMedSearch : Lu_2012_PLoS.One_7_e32288
PubMedID: 22359679

Title : Cholinergic and non-cholinergic functions of two acetylcholinesterase genes revealed by gene-silencing in Tribolium castaneum - Lu_2012_Sci.Rep_2_288
Author(s) : Lu Y , Park Y , Gao X , Zhang X , Yao J , Pang YP , Jiang H , Zhu KY
Ref : Sci Rep , 2 :288 , 2012
Abstract : We compared biological functions of two acetylcholinesterase genes (TcAce1 and TcAce2) in Tribolium castaneum, a globally distributed major pest of stored grain products and an emerging model organism, by using RNA interference. Although both genes expressed at all developmental stages and mainly in the brain, the transcript level of TcAce1 was 1.2- to 8.7-fold higher than that of TcAce2, depending on developmental stages. Silencing TcAce1 in 20-day larvae led to 100% mortality within two weeks after eclosion and increased larval susceptibilities to anticholinesterase insecticides. In contrast, silencing TcAce2 did not show insect mortality and significantly affect insecticide susceptibility, but delayed insect development and reduced female egg-laying and egg hatching. These results demonstrate for the first time that TcAce1 plays a major role in cholinergic functions and is the target of anticholinesterase insecticides, whereas TcAce2 plays an important, non-cholinergic role in female reproduction, embryo development, and growth of offspring.
ESTHER : Lu_2012_Sci.Rep_2_288
PubMedSearch : Lu_2012_Sci.Rep_2_288
PubMedID: 22371826

Title : A novel small Odorranalectin-bearing cubosomes: preparation, brain delivery and pharmacodynamic study on amyloid-beta(2)(5)(-)(3)(5)-treated rats following intranasal administration - Wu_2012_Eur.J.Pharm.Biopharm_80_368
Author(s) : Wu H , Li J , Zhang Q , Yan X , Guo L , Gao X , Qiu M , Jiang X , Lai R , Chen H
Ref : Eur J Pharm Biopharm , 80 :368 , 2012
Abstract : Because of the immunogenicity and toxicity in vivo of large molecules such as lectins, the application of these molecules is remarkably restricted in drug delivery systems. In this study, to improve the brain drug delivery and reduce the immunogenicity of traditional lectin modified delivery system, Odorranalectin (OL, 1700 Da), a novel non-immunogenic small peptide, was selected to establish an OL-modified cubosomes (Cubs) system. The streptavidin (SA)-conjugated Cubs were prepared by incorporating maleimide-PEG-oleate and taking advantage of its thiol group binding reactivity to conjugate with 2-iminothiolane thiolated SA; mono-biotinylated OL was then coupled with the SA-modified Cubs. The OL-decorated Cubs (OL-Cubs) devised via a non-covalent SA-biotin "bridge" made it easy to conjugate OL and determine the number of ligands on the surface of the Cubs using sensitive chemiluminescent detection. Retention of the bio-recognitive activity of OL after covalent coupling was verified by hemagglutination testing. Nose-to-brain delivery characteristic of OL-Cubs was investigated by in vivo fluorescent biodistribution using coumarin-6 as a marker. The relative uptake of coumarin carried by OL-Cubs was 1.66- to 3.46-fold in brain tissues compared to that incorporated in the Cubs. Besides, Gly14-Humanin (S14G-HN) as a model peptide drug was loaded into cubosomes and evaluated for its pharmacodynamics on Alzheimer's disease (AD) rats following intranasal administration by Morris water maze test and acetylcholinesterase activity determination. The results suggested that OL functionalization enhanced the therapeutic effects of S14G-HN-loaded cubosomes on AD. Thus, OL-Cubs might offer a novel effective and noninvasive system for brain drug delivery, especially for peptides and proteins.
ESTHER : Wu_2012_Eur.J.Pharm.Biopharm_80_368
PubMedSearch : Wu_2012_Eur.J.Pharm.Biopharm_80_368
PubMedID: 22061263

Title : In vivo toxicity and immunogenicity of wheat germ agglutinin conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles for intranasal delivery to the brain - Liu_2011_Toxicol.Appl.Pharmacol_251_79
Author(s) : Liu Q , Shao X , Chen J , Shen Y , Feng C , Gao X , Zhao Y , Li J , Zhang Q , Jiang X
Ref : Toxicol Appl Pharmacol , 251 :79 , 2011
Abstract : Biodegradable polymer-based nanoparticles have been widely studied to deliver therapeutic agents to the brain after intranasal administration. However, knowledge as to the side effects of nanoparticle delivery system to the brain is limited. The aim of this study was to investigate the in vivo toxicity and immunogenicity of wheat germ agglutinin (WGA) conjugated poly(ethylene glycol)-poly(lactic acid) nanoparticles (WGA-NP) after intranasal instillation. Sprague-Dawley rats were intranasally given WGA-NP for 7 continuous days. Amino acid neurotransmitters, lactate dehydrogenase (LDH) activity, reduced glutathione (GSH), acetylcholine, acetylcholinesterase activity, tumor necrosis factor alpha (TNF-alpha) and interleukin-8 (IL-8) in rat olfactory bulb (OB) and brain were measured to estimate the in vivo toxicity of WGA-NP. Balb/C mice were intranasally immunized by WGA-NP and then WGA-specific antibodies in serum and nasal wash were detected by indirect ELISA. WGA-NP showed slight toxicity to brain tissue, as evidenced by increased glutamate level in rat brain and enhanced LDH activity in rat OB. No significant changes in acetylcholine level, acetylcholinesterase activity, GSH level, TNF-alpha level and IL-8 level were observed in rat OB and brain for the WGA-NP group. WGA-specific antibodies in mice serum and nasal wash were not increased after two intranasal immunizations of WGA-NP. These results demonstrate that WGA-NP is a safe carrier system for intranasal delivery of therapeutic agents to the brain.
ESTHER : Liu_2011_Toxicol.Appl.Pharmacol_251_79
PubMedSearch : Liu_2011_Toxicol.Appl.Pharmacol_251_79
PubMedID: 21163285

Title : Stage-dependent tolerance of the German cockroach, Blattella germanica for dichlorvos and propoxur - Qian_2010_J.Insect.Sci_10_201
Author(s) : Qian K , Wei X , Zeng X , Liu T , Gao X
Ref : J Insect Sci , 10 :201 , 2010
Abstract : tage-dependent dichlorvos and propoxur tolerance in a field population of the German cockroach, Blattella germanica Linnaeus (Blatodea: Blattellidae), was investigated in the laboratory using a topical application bioassay. The results showed the 6 week-old nymphs were more tolerant to dichlorvos and propoxur than the other ages tested. LD(5)(0) values of dichlorvos and propoxur for the 6 week-old nymphs were 2.003 microg per insect and 5.296 microg per insect, respectively. Tolerance ratios of 18.55-fold and 4.98-fold for LD(5)(0) were obtained from 6-week-old nymphs compared to 4 week-old nymphs. The specific activity of acetylcholinesterase (AChE) from 1 week-old nymphs was the highest among all tested developmental stages of nymphs and adult males and females. The specific activity of AChE decreased significantly with increasing age. The sensitivity of AChE to dichlorvos was the highest with a k(i) value of 3.12 x 10(4) mol(-)(1)min(-)(1) in the last nymphal stage of B. germanica (about 6 weeks-old). The AChE from 4 week-old nymphs was the most sensitive to propoxur, with the highest k(i) value being 2.63 x 10(5) mol(-)(1) min(-)(1). These results indicated that the different developmental stages and sexes of B. germanica affected the inhibition of AChE by dichlorvos and propoxur.
ESTHER : Qian_2010_J.Insect.Sci_10_201
PubMedSearch : Qian_2010_J.Insect.Sci_10_201
PubMedID: 21268698

Title : Quantitative and qualitative changes of the carboxylesterase associated with beta-cypermethrin resistance in the housefly, Musca domestica (Diptera: Muscidae) - Zhang_2010_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_156_6
Author(s) : Zhang L , Shi J , Shi X , Liang P , Gao J , Gao X
Ref : Comparative Biochemistry & Physiology B Biochem Mol Biol , 156 :6 , 2010
Abstract : Mechanisms of esterase-mediated pyrethroid resistance were analyzed based on our previous works in a strain of the housefly, Musca domestica. The carboxylesterase gene, MdalphaE7, was cloned and sequenced from susceptible (CSS) and resistant (CRR) strains, and a total of nine amino acid substitutions were found. The mutation, Trp(251)-Ser appeared to play a role in beta-cypermethrin resistance and cross-resistance between organophosphates (OPs) and pyrethroids in the CRR strain. Quantitative real-time PCR showed that MdalphaE7 was over-expressed in the CRR strain, the reciprocal cross progeny F(1) and back-cross progeny BC(2) compared with the CSS strain, respectively. Two alpha-cynaoester substrates as surrogates for beta-cypermethrin and deltamethrin, were synthesized to determine the pyrethroid hydrolase activity. Results showed that carboxylesterases from the CRR strain hydrolyzed cypermethrin/deltamethrin-like substrate 9.05- and 13.53-fold more efficiently than those from the CSS strain, respectively. Our studies suggested that quantitative and qualitative changes in the carboxylesterase might contribute together to pyrethroid resistance in the CRR strain.
ESTHER : Zhang_2010_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_156_6
PubMedSearch : Zhang_2010_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_156_6
PubMedID: 20117228
Gene_locus related to this paper: musdo-EST23aes07

Title : Inheritance of resistance to a new non-steroidal ecdysone agonist, fufenozide, in the diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae) - Sun_2010_Pest.Manag.Sci_66_406
Author(s) : Sun J , Liang P , Gao X
Ref : Pest Manag Sci , 66 :406 , 2010
Abstract : BACKGROUND: The diamondback moth (DBM), Plutella xylostella (L.), is a cosmopolitan pest of cruciferous crops. Fufenozide, a novel non-steroidal ecdysone agonist, exhibits good efficacy and plays an increasingly important role in the control of Lepidopterous pests in China. A laboratory strain of DBM was selected for resistance to fufenozide, and the genetic basis of resistance was studied. RESULTS: The resistant strain, selected under laboratory conditions, exhibited a higher level of resistance to fufenozide (302.8-fold based on LC(50)s) than the laboratory susceptible strain. Mortality data from the testing of F(1) progeny of reciprocal crosses of resistant and susceptible DBM indicated that resistance was autosomal and incompletely recessive with a degree of dominance of -0.664. Chi-square analysis from responses of a backcross of crossed F(1) progeny and the resistant strain and F(2) progeny were highly significant, suggesting that the resistance was probably controlled by more than one gene. The estimated realised heritability (h(2)) of fufenozide resistance was 0.08, indicating that diamondback moth may have a lower chance of developing resistance to fufenozide than other kinds of insecticide. CONCLUSION: The resistance of DBM to fufenozide might be autosomal and incompletely recessive, and the resistance is probably controlled by more than one gene. These results provide the basic information for pest management programmes.
ESTHER : Sun_2010_Pest.Manag.Sci_66_406
PubMedSearch : Sun_2010_Pest.Manag.Sci_66_406
PubMedID: 19960491

Title : Gender differences in cognitive ability associated with genetic variants of NLGN4 - Zhang_2010_Neuropsychobiology_62_221
Author(s) : Zhang K , Gao X , Qi H , Li J , Zheng Z , Zhang F
Ref : Neuropsychobiology , 62 :221 , 2010
Abstract : Neuroligin-4 (NL4), encoded by the NLGN4 gene on the X chromosome, is a neuronal-specific brain membrane protein which plays an important role in the formation of functional presynaptic elements and axon specialization. The genetic variants of NLGN4 affect the biological function of NL4, resulting in the manifestation of different psychiatric disorders. The present study investigates the influence of these genetic variants on cognitive performance. The cognitive abilities of 351 subjects were evaluated using the Chinese Wechsler Intelligence Scale Children. The haplotypes were assigned with the PHASE program. The ANOVA method was applied to investigate the relationship between single SNP, the identified target haplotypes and cognitive performance in a random sample. We observed that the X(C) allele of rs5916271 and X(A) allele of the re6638575 carriers had significantly higher cognitive ability performances than the noncarrier boys (p < 0.05). The target haplotype composed of 2 allele (X(CA+)) carriers also displayed a higher cognitive performance than that of the noncarriers boys. The genetic polymorphism of NLGN4 also had a significant effect on the boys' cognitive ability and other intelligence factors. Future research will involve determining the relationship between NLGN4 and personal cognitive ability.
ESTHER : Zhang_2010_Neuropsychobiology_62_221
PubMedSearch : Zhang_2010_Neuropsychobiology_62_221
PubMedID: 20714171

Title : Positive association of neuroligin-4 gene with nonspecific mental retardation in the Qinba Mountains Region of China - Qi_2009_Psychiatr.Genet_19_1
Author(s) : Qi H , Xing L , Zhang K , Gao X , Zheng Z , Huang S , Guo Y , Zhang F
Ref : Psychiatr Genet , 19 :1 , 2009
Abstract : OBJECTIVE: Neuroligin-4 is essential for proper brain function. Some studies indicate a close relationship between neuroligin-4 and several human psychiatric conditions. METHODS: The case-control method was used to study the association between nonspecific mental retardation (NSMR) and genetic variants of neuroligin-4 gene (NLGN4). Five single nucleotide polymorphisms (SNPs: rs5916271, rs7049300, rs6638575, rs3810686, and rs1882260) were genotyped by PCR-RFLP/SSCP method in the NLGN4. RESULTS: Individual SNP analysis shows significant differences at SNPs rs3810686 and rs1882260 for allele frequency when NSMR cases and controls [odds ratio (OR)=1.589, 95% confidence interval (CI)=1.035-2.438, chi2=4.53, df=1, P=0.033; OR=2.050, 95% CI=1.211-3.470, chi2=7.38, df=1, P=0.007, respectively] were compared. Further haplotype analysis indicates that there are two haplotype sets, rs3810686-rs1882260 and rs6638575-rs3810686-rs1882260, which show statistical differences between NSMR cases and controls (chi2=6.79, df=2, global P=0.034; chi2=9.29, df=2, global P=0.0096, respectively). CONCLUSION: The results suggest a positive association between the genetic variants of the NLGN4 and NSMR in the Chinese children from Qinba Mountains Region.
ESTHER : Qi_2009_Psychiatr.Genet_19_1
PubMedSearch : Qi_2009_Psychiatr.Genet_19_1
PubMedID: 19125102

Title : Carboxylesterase activity, cDNA sequence, and gene expression in malathion susceptible and resistant strains of the cotton aphid, Aphis gossypii - Pan_2009_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_152_266
Author(s) : Pan Y , Guo H , Gao X
Ref : Comparative Biochemistry & Physiology B Biochem Mol Biol , 152 :266 , 2009
Abstract : Levels of insecticide resistance, carboxylesterase activity, carboxylesterase expression, and the cDNA sequence of carboxylesterase gene were investigated in malathion resistant and susceptible strains of cotton aphids, Aphis gossypii (Glover). The resistant strain (MRR) exhibited 80.6-fold resistance to malathion compared to the susceptible strain (MSS) in cotton aphids. Five substrates, alpha-naphthyl acetate (alpha-NA), beta-naphthyl acetate (beta-NA), alpha-naphthyl propionate (alpha-NPr), alpha-naphthyl butyrate (alpha-NB), alpha-naphthyl caprylate (alpha-NC) and S-methyl thiobutyrate (S-MTB) were used to determine carboxylesterase activity in MRR and MSS strains of cotton aphids. Carboxylesterase activity was significantly higher in MRR strain than in MSS strain, 3.7-fold for alpha-NA, 3.0-fold for beta-NA, 2.0-fold for alpha-NPr, 2.9-fold for alpha-NB and 1.6-fold for alpha-NC, While for S-MTB, there was nearly no difference between the two strains. Two site mutations (K14Q and N354D) with high frequency were also found by sequence analysis in the MRR strain, compared with the MSS strain. The levels of gene expression for carboxylesterase of both MRR and MSS strains were determined by real-time quantitative PCRs. Compared with the MSS strain, the relative transcription levels and gene copy numbers of the carboxylesterase were 1.99- and 4.42-fold in the MRR strain, respectively. These results indicated that the increased expression of the carboxylesterase resulted from the increased transcription levels of carboxylesterase mRNA and gene copy numbers and combined with the site mutants might play role in cotton aphid resistance to malathion.
ESTHER : Pan_2009_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_152_266
PubMedSearch : Pan_2009_Comp.Biochem.Physiol.B.Biochem.Mol.Biol_152_266
PubMedID: 19110065
Gene_locus related to this paper: aphgo-cxest

Title : Multiple mechanisms responsible for differential susceptibilities of Sitobion avenae (Fabricius) and Rhopalosiphum padi (Linnaeus) to pirimicarb - Lu_2009_Bull.Entomol.Res_99_611
Author(s) : Lu Y , Gao X
Ref : Bull Entomol Res , 99 :611 , 2009
Abstract : Both Sitobion avenae (Fabricius) and Rhopalosiphum padi (Linnaeus) are the most important pests of wheat in China and usually coexist on the late period of wheat growth. Pirimicarb was introduced into China for wheat aphid control in early 1990s, and differential susceptibilities of Sitobion avenae (Fabricius) and Rhopalosiphum padi (Linnaeus) to pirimicarb have been observed. A bioassay exhibited that Rhopalosiphum padi possessed significantly higher susceptibility to pirimicarb than Sitobion avenae. The addition of synergists DEF, an esterase inhibitor, PBO, a cytochrome P450 monooxygenase inhibitor, and DEM, a glutathione S-transferase inhibitor, resulted in apparent reductions in the differential susceptibilities, suggesting the involvement of the above three detoxification enzymes in the differential susceptibility to pirimicarb between Sitobion avenae and Rhopalosiphum padi. A biochemical analysis showed that the activities of carboxylesterases and glutathione S-transferases were significantly higher in Sitobion avenae than in Rhopalosiphum padi, consistent with the results of synergism. Acetylcholinesterase is the target enzyme of pirimicarb and the sensitivity of acetylcholinesterase to pirimicarb was significantly higher in Rhopalosiphum padi than in Sitobion avenae. The combined results suggest that multiple mechanisms are likely to be responsible for differential susceptibilities to pirimicarb between Sitobion avenae and Rhopalosiphum padi. The results obtained from this study should be helpful in the rational applications of insecticides.
ESTHER : Lu_2009_Bull.Entomol.Res_99_611
PubMedSearch : Lu_2009_Bull.Entomol.Res_99_611
PubMedID: 19413913

Title : Acute toxicity of the pesticide methomyl on the topmouth gudgeon (Pseudorasbora parva): mortality and effects on four biomarkers - Li_2008_Fish.Physiol.Biochem_34_209
Author(s) : Li H , Jiang H , Gao X , Wang X , Qu W , Lin R , Chen J
Ref : Fish Physiol Biochem , 34 :209 , 2008
Abstract : In this study, the acute toxicity of the pesticide methomyl on the topmouth gudgeon (Pseudorasbora parva) was evaluated using mortality and the activity of the enzymes acetylcholinesterase (AChE), glutathione S-transferases (GSTs), glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) as endpoints. LC50 values were 1.228, 0.782, 0.538, and 0.425 mg/l at 24, 48, 72, and 96 h of exposure, respectively. Methomyl caused a sharp decrease in specific activity of brain AChE around 48% at concentrations between 0.043 and 0.213 mg/l. A reduction higher than 40% in liver GST activity at concentrations between 0.085 and 0.213 mg/l was found, whereas no significant effects were observed in intestinal GST. A significant concentration-dependent decrease of GOT activity was found after 24 h of exposure to the pesticide but not after 96 h. No significant effects on GPT activity were observed. These results indicate that at the concentrations tested, methomyl is acutely toxic to the species P. parva, causing mortality, neurotoxic effects, and changes in some hepatic enzymes.
ESTHER : Li_2008_Fish.Physiol.Biochem_34_209
PubMedSearch : Li_2008_Fish.Physiol.Biochem_34_209
PubMedID: 18665458

Title : Potential therapeutic targets of huperzine A for Alzheimer's disease and vascular dementia - Zhang_2008_Chem.Biol.Interact_175_396
Author(s) : Zhang HY , Zheng CY , Yan H , Wang ZF , Tang LL , Gao X , Tang XC
Ref : Chemico-Biological Interactions , 175 :396 , 2008
Abstract : Huperzine A (HupA), a novel Lycopodium alkaloid isolated from Chinese folk medicine Huperzia serrata (Qian Ceng Ta), is a potent, selective and well-tolerated inhibitor of acetylcholinesterase (AChE). It has been proven to significantly improve the learning and memory impairment in Alzheimer's disease (AD) and vascular dementia (VaD) patients in China. Interestingly, our recent data indicate that HupA also possesses other protective functions. This paper will give an overview on the protective effects of HupA, which includes regulating beta-amyloid precursor protein (APP) metabolism, protecting against Abeta-mediated oxidative stress, apoptosis and mitochondrial dysfunction, as well as anti-inflammation. The multiple neuroprotective effects of HupA might yield additional beneficial effects in AD and VaD therapy.
ESTHER : Zhang_2008_Chem.Biol.Interact_175_396
PubMedSearch : Zhang_2008_Chem.Biol.Interact_175_396
PubMedID: 18565502

Title : Inheritance of beta-cypermethrin resistance in the housefly Musca domestica (Diptera: Muscidae) - Zhang_2008_Pest.Manag.Sci_64_185
Author(s) : Zhang L , Shi J , Gao X
Ref : Pest Manag Sci , 64 :185 , 2008
Abstract : BACKGROUND:Beta-cypermethrin, a synthetic pyrethroid insecticide, was applied frequently in the control of health pests including houseflies, Musca domestica L., in China. However, different levels of resistance to beta-cypermethrin were monitored in field strains of houseflies. A strain of M. domestica, 4420-fold resistant to beta-cypermethrin after continuous 25 generations of selection, was used in this paper to determine the mode of inheritance of pyrethroid resistance. RESULTS: The estimated realized heritability (h(2)) of beta-cypermethrin resistance was 0.30 in this resistant strain. Results of bioassays showed no significant difference in values of LD(50) and slope of log dose-probit lines between reciprocal progenies F(1) and F'(1), and yielded values of - 0.10 (F(1)) and - 0.11 (F'(1)) for the degree of dominance (D). Chi-square analysis from responses of self-bred and backcross progenies (F(2), BC(1) and BC(2) respectively) indicated that the null hypothesis, a single gene responsible for resistance, was accepted. The minimum number of independent segregation genes was 0.93 for F(1) by Lande's method.CONCLUSION: It was concluded that beta-cypermethrin resistance in the housefly was inherited as a single, major, autosomal and incompletely recessive factor. These results would provide the basic information for pest management programmes.
ESTHER : Zhang_2008_Pest.Manag.Sci_64_185
PubMedSearch : Zhang_2008_Pest.Manag.Sci_64_185
PubMedID: 18069658

Title : Beta-cypermethrin resistance associated with high carboxylesterase activities in a strain of house fly, Musca domestica (Diptera: Muscidae) - Zhang_2007_Pestic.Biochem.Physiol_89_65
Author(s) : Zhang L , Gao X , Liang P
Ref : Pesticide Biochemistry and Physiology , 89 :65 , 2007
Abstract : A housefly strain, originally collected in 1998 from a dump in Beijing, was selected with beta-cypermethrin to generate a resistant strain (CRR) in order to characterize the resistance and identify the possible mechanisms involved in the pyrethroid resistance. The resistance was increased from 2.56- to 4419.07-fold in the CRR strain after 25 consecutive generations of selection compared to a laboratory susceptible strain (CSS). The CRR strain also developed different levels of cross-resistance to various insecticides within and outside the pyrethroid group such as abamectin. Synergists, piperonyl butoxide (PBO) and S,S,S-tributyl phosphorotrithioate (DEF), increased beta-cypermethrin toxicity 21.88- and 364.29-fold in the CRR strain as compared to 15.33- and 2.35-fold in the CSS strain, respectively. Results of biochemical assays revealed that carboxylesterase activities and maximal velocities to five naphthyl-substituted substrates in the CRR strain were significantly higher than that in the CSS strain, however, there was no significant difference in glutathione S-transferase activity and the level of total cytochrome P450 between the CRR and CSS strains. Therefore, our studies suggested that carboxylesterase play an important role in beta-cypermethrin resistance in the CRR strain.
ESTHER : Zhang_2007_Pestic.Biochem.Physiol_89_65
PubMedSearch : Zhang_2007_Pestic.Biochem.Physiol_89_65

Title : Huperzine A attenuates mitochondrial dysfunction in beta-amyloid-treated PC12 cells by reducing oxygen free radicals accumulation and improving mitochondrial energy metabolism - Gao_2006_J.Neurosci.Res_83_1048
Author(s) : Gao X , Tang XC
Ref : Journal of Neuroscience Research , 83 :1048 , 2006
Abstract : We observed previously that huperzine A (HupA), a selective acetylcholinesterase inhibitor, can counteract neuronal apoptosis and cell damage induced by several neurotoxic substances, and that this neuroprotective action somehow involves the mitochondria. We investigated the ability of HupA to reduce mitochondrial dysfunction in neuron-like rat pheochromocytoma (PC12) cells exposed in culture to the amyloid beta-peptide fragment 25-35 (Abeta(25-35)). After exposure to 1 microM Abeta(25-35) for various periods, cells exhibited a rapid decline of ATP levels and obvious disruption of mitochondrial membrane homeostasis and integrity as determined by characteristic morphologic alterations, reduced membrane potential, and decreased activity of ion transport proteins. In addition, Abeta(25-35) treatment also led to inhibition of key enzyme activities in the electron transport chain and the tricarboxylic acid cycle, as well as an increase of intracellular reactive oxygen species (ROS). Pre-incubation with HupA for 2 hr not only attenuated these signs of cellular stress caused by Abeta, but also enhanced ATP concentration and decreased ROS accumulation in unharmed normal cells. Those results indicate that HupA protects mitochondria against Abeta-induced damages, at least in part by inhibiting oxidative stress and improving energy metabolism, and that these protective effects reduce the apoptosis of neuronal cells exposed to this toxic peptide.
ESTHER : Gao_2006_J.Neurosci.Res_83_1048
PubMedSearch : Gao_2006_J.Neurosci.Res_83_1048
PubMedID: 16493671

Title : Immobilized Pseudomonas cepacia lipase for biodiesel fuel production from soybean oil - Noureddini_2005_Bioresour.Technol_96_769
Author(s) : Noureddini H , Gao X , Philkana RS
Ref : Bioresour Technol , 96 :769 , 2005
Abstract : Enzymatic transesterification of soybean oil with methanol and ethanol was studied. Of the nine lipases that were tested in the initial screening, lipase PS from Pseudomonas cepacia resulted in the highest yield of alkyl esters. Lipase from Pseudomonas cepacia was further investigated in immobilized form within a chemically inert, hydrophobic sol-gel support. The gel-entrapped lipase was prepared by polycondensation of hydrolyzed tetramethoxysilane and iso-butyltrimethoxysilane. Using the immobilized lipase PS, the effects of water and alcohol concentration, enzyme loading, enzyme thermal stability, and temperature in the transesterification reaction were investigated. The optimal conditions for processing 10 g of soybean oil were: 35 degrees C, 1:7.5 oil/methanol molar ratio, 0.5 g water and 475 mg lipase for the reactions with methanol, and 35 degrees C, 1:15.2 oil/ethanol molar ratio, 0.3 g water, 475 mg lipase for the reactions with ethanol. Subject to the optimal conditions, methyl and ethyl esters formation of 67 and 65 mol% in 1h of reaction were obtained for the immobilized enzyme reactions. Upon the reaction with the immobilized lipase, the triglycerides reached negligible levels after the first 30 min of the reaction and the immobilized lipase was consistently more active than the free enzyme. The immobilized lipase also proved to be stable and lost little activity when was subjected to repeated uses.
ESTHER : Noureddini_2005_Bioresour.Technol_96_769
PubMedSearch : Noureddini_2005_Bioresour.Technol_96_769
PubMedID: 15607189

Title : Polymorphisms in a carboxylesterase gene between organophosphate-resistant and -susceptible Aphis gossypii (Homoptera: Aphididae) - Sun_2005_J.Econ.Entomol_98_1325
Author(s) : Sun L , Zhou X , Zhang J , Gao X
Ref : J Econ Entomol , 98 :1325 , 2005
Abstract : Resistance to omethoate was suppressible by the hydrolytic enzyme inhibitor SSS-tributyl phosphorotrithioate in a laboratory-selected resistant cotton aphid, Aphis gossypii Glover, strain, suggesting the involvement of hydrolytic enzymes in the detoxification process. The kinetic properties of carboxylesterases from both resistant and susceptible cotton aphids were characterized by four acyl ester substrates: alpha-naphthyl acetate (alpha-NA), alpha-naphthyl butyrate (alpha-NB), alpha-naphthyl phosphate (alpha-NP), and beta-naphthyl phosphate (beta-NP). No significant differences of carboxylesterase activity were found between resistant and susceptible strains by using either alpha-NP or beta-NP as substrates. In contrast, the susceptible A. gossypii exhibited significantly higher activity compared with resistant aphids with either alpha-NA or alpha-NB as substrates. To understand the molecular basis of this esterase-mediated resistance, carboxylesterase genes from both strains were cloned. Two genes share 99.4% identity at the nucleic acid level and 99.2% identity at the amino acid level. The full length of the cDNA opening reading frame is 1581 bp, encoding 526 amino acids. Four amino acid substitutions, Thr210 --> Met210, Asn294 --> Lys294, Gly408 --> Asp408, and Ser441 --> Phe441, were identified in the resistant strain. Probing of Southern blots with the 0.5 kb esterase fragment showed the same banding patterns and intensities with genomic DNA extracts from both resistant and susceptible A. gossypii. Furthermore, the MspI and HpaII fragments are the same in both strains, indicating there is no methylation of sequences detected by the probe. The combined results suggest that the structural gene substitution is likely the molecular basis of the organophosphate resistance in this laboratory-selected cotton aphid strain.
ESTHER : Sun_2005_J.Econ.Entomol_98_1325
PubMedSearch : Sun_2005_J.Econ.Entomol_98_1325
PubMedID: 16156587
Gene_locus related to this paper: aphgo-cxest

Title : Decreased amphetamine-induced locomotion and improved latent inhibition in mice mutant for the M5 muscarinic receptor gene found in the human 15q schizophrenia region - Wang_2004_Neuropsychopharmacology_29_2126
Author(s) : Wang H , Ng K , Hayes D , Gao X , Forster G , Blaha C , Yeomans J
Ref : Neuropsychopharmacology , 29 :2126 , 2004
Abstract : M5 muscarinic receptors are coexpressed with D2 dopamine receptors in the ventral tegmentum and striatum, and are important for reward in rodents. Previously, we reported that disruption of the M5 receptor gene in mice reduced dopamine release in the nucleus accumbens. In this study, we established a polymerase chain reaction (PCR) genotyping method for M5 mutant mice, and, using RT-PCR, found that M5 mRNA expression was highest in the ventral tegmentum, striatum, and thalamus in wild-type mice. In the M5 mutant mice, D2 mRNA expression was increased in several brain structures, including the striatum. Genome mapping studies showed the M5 gene is localized to chromosome 2E4 in mice, and to 15q13 in humans in the region that has been linked to schizophrenia. Amphetamine-induced locomotion, but not baseline locomotion or motor functions, decreased in M5 mutant mice, consistent with lower accumbal dopamine release. Previous reports found latent inhibition improvement in rats following nucleus accumbens lesions, or blockade of dopamine D2 receptors with neuroleptic drugs. Here, latent inhibition was significantly increased in M5 mutant mice as compared with controls, consistent with reduced dopamine function in the nucleus accumbens. In summary, our results showed that M5 gene disruption in mice decreased amphetamine-induced locomotion and increased latent inhibition, suggesting that increased M5 mesolimbic function may be relevant to schizophrenia.
ESTHER : Wang_2004_Neuropsychopharmacology_29_2126
PubMedSearch : Wang_2004_Neuropsychopharmacology_29_2126
PubMedID: 15213703

Title : Cloning, sequencing, and characterization of the genetic region relevant to biosynthesis of the lipopeptides iturin A and surfactin in Bacillus subtilis - Yao_2003_Curr.Microbiol_47_272
Author(s) : Yao S , Gao X , Fuchsbauer N , Hillen W , Vater J , Wang J
Ref : Curr Microbiol , 47 :272 , 2003
Abstract : Bacillus subtilis B3 was found to produce lipopeptides iturins and fengycin that have activity against several plant pathogens such as Fusarium graminearum, Rhizoctonia solani, Rhizoctonia cerealis, and Pyricularia grisea. A 3642-bp genomic region of B. subtilis B3 comprising srfDB3, aspB3, lpaB3, and yczEB3 genes that resulted in biosynthesis of surfactin in B. subtilis 168 was cloned, sequenced, and characterized. Among them, the srfDB3 gene encodes thioesterase, which is required for biosynthesis of surfactin in B. subtilis; the aspB3 gene encodes a putative aspartate aminotransferase-like protein; the lpaB3 encodes phosphopantetheinyl transferase, which shows high identity to the product of lpa-14 gene regulating the biosynthesis of iturin A and surfactin in B. subtilis RB14; the yczEB3 encodes a YczE-like protein with significant similarities in signal peptide and part of the ABC transport system. The genetic regions between the srfD gene and lpa gene from B. subtilis B3 and B. subtilis A13, which produces iturin A, contain an approximate 1-kb nucleotide fragment encoding an aspartate aminotransferase-like protein; however, the relevant regions from B. subtilis 168 and B. subtilis ATCC21332 producing surfactin comprise an approximately 4-kb nucleotide fragment encoding four unknown proteins. There is 73% identity between the Lpa family and the Sfp family, although both are highly conserved.
ESTHER : Yao_2003_Curr.Microbiol_47_272
PubMedSearch : Yao_2003_Curr.Microbiol_47_272
PubMedID: 14629006
Gene_locus related to this paper: bacsu-SRFD

Title : Characterisation of Insensitive Acetylcholinesterase in Insecticide-Resistant Cotton Aphids, Aphis gossypii Glover (Homoptera: Aphididae) - Moores_1996_Pestic.Biochem.Physiol_56_102
Author(s) : Moores GD , Gao X , Denholm I , Devonshire AL
Ref : Pesticide Biochemistry and Physiology , 56 :102 , 1996
Abstract : Levels of insecticide resistance, total esterase activity, and acetylcholinesterase (AChE) sensitivity to inhibition by insecticides were investigated in three clones of Aphis gossypii Glover. Compared with LC50 values for a susceptible clone (171B), clone 968E showed high (>20-fold) resistance to most of the carbamate and organophosphorus insecticides tested, whereas clone 1081K only exhibited strong resistance to some carbamate insecticides.171B aphids had low esterase activity combined with an AChE variant showing baseline sensitivity to organophosphorus and carbamate insecticides. 968E combined high esterase activity with broad-spectrum AChE insensitivity to these chemicals. 1081K had low esterase activity and an AChE variant that was insensitive to pirimicarb and a smaller range of OP insecticides. These findings demonstrate the occurrence of at least two insensitive AChE variants in A. gossypii,whose contrasting insensitivity profiles permit rapid diagnosis using a kinetic microplate assay. Altered AChE appeared to be the main mechanism of resistance to both organophosphorus and carbamate insecticides in these clones.
ESTHER : Moores_1996_Pestic.Biochem.Physiol_56_102
PubMedSearch : Moores_1996_Pestic.Biochem.Physiol_56_102