An ultrasensitivity detecting assay for acetylcholinesterase (AChE) activity was developed based on "covalent assembly" and signal amplification strategic approaches. After hydrolyzing thioacetylcholine by AChE and participation of thiol in a self-inducing cascade accelerated by the Meldrum acid derivatives of 2-[bis(methylthio) methylene] malonitrile (CA-2), mercaptans triggered an intramolecular cyclization assembly by the probe of 2-(2,2-dicyanovinyl)-5-(diethylamino) phenyl 2,4-dinitrobenzenesulfonate (Sd-I) to produce strong fluorescence. The limit of detection for AChE activity was as low as 0.0048 mU/mL. The detection system also had a good detecting effect on AChE activity in human serum and could also be used to screen its inhibitors. By constructing a Sd-I@agarose hydrogel with a smartphone, a point-of-care detection of AChE activity was achieved again.
Title: Thyroid endocrine disruption and neurotoxicity of gestodene in adult female mosquitofish (Gambusia affinis) Tan J, Liang C, Guo Y, Zou H, Ye J, Hou L, Wang X Ref: Chemosphere, :137594, 2022 : PubMed
The frequent detection of progestins in various aquatic environments and their potential endocrine disruptive effects in fish have attracted increasing attention worldwide. However, data on their effects on thyroid function and neurotoxicity in fish are limited, and the underlying mechanisms remain unclear. Here, the effects of gestodene (GES, a common progestin) on the thyroid endocrine and nervous systems of mosquitofish (Gambusia affinis) were studied. Adult female fish were exposed to GES at environmentally relevant concentrations (4.4-378.7 ng/L) for 60 days. The results showed that exposure to 378.7 ng/L GES caused a significant decrease in fish growth compared with the control and a marked reduction in the total distance traveled (50.6%) and swimming velocity (40.1-61.9%). The triiodothyronine (T3) levels were significantly increased by GES in a dose-dependent manner, whereas those of tetraiodothyronine (T4) were significantly decreased only at the G500 concentration. The acetylcholinesterase (AChE) activity was decreased significantly in the 4.42 ng/L GES treatments, but increased significantly at 378.67 ng/L. In the brain, a strong increase in the transcriptional levels of bdnf, trh, and dio2 was observed in fish after the 378.7 ng/L treatment. In addition, chronic exposure to GES caused colloid depletion with a concentration-dependent manner in the thyroid, and angiectasis, congestion, and vacuolar necrosis in the brain. These findings provide a better understanding of the effects of GES and associated underlying mechanisms in G. affinis.
Title: Potential for and Distribution of Enzymatic Biodegradation of Polystyrene by Environmental Microorganisms Hou L, Majumder EL Ref: Materials (Basel), 14:, 2021 : PubMed
Polystyrene (PS) is one of the main polymer types of plastic wastes and is known to be resistant to biodegradation, resulting in PS waste persistence in the environment. Although previous studies have reported that some microorganisms can degrade PS, enzymes and mechanisms of microorganism PS biodegradation are still unknown. In this study, we summarized microbial species that have been identified to degrade PS. By screening the available genome information of microorganisms that have been reported to degrade PS for enzymes with functional potential to depolymerize PS, we predicted target PS-degrading enzymes. We found that cytochrome P4500s, alkane hydroxylases and monooxygenases ranked as the top potential enzyme classes that can degrade PS since they can break C-C bonds. Ring-hydroxylating dioxygenases may be able to break the side-chain of PS and oxidize the aromatic ring compounds generated from the decomposition of PS. These target enzymes were distributed in Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes, suggesting a broad potential for PS biodegradation in various earth environments and microbiomes. Our results provide insight into the enzymatic degradation of PS and suggestions for realizing the biodegradation of this recalcitrant plastic.
The endocannabinoid system (ECS) is involved in a wide range of biological functions and comprises cannabinoid receptors and enzymes responsible for endocannabinoid synthesis and degradation. Over the past 2 decades, significant advances toward developing drugs and positron emission tomography (PET) tracers targeting different components of the ECS have been made. Herein, we summarized the recent development of PET tracers for imaging cannabinoid receptors 1 (CB1R) and 2 (CB2R) as well as the key enzymes monoacylglycerol lipase (MAGL) and fatty acid amide hydrolase (FAAH), particularly focusing on PET neuroimaging applications. State-of-the-art PET tracers for the ECS will be reviewed including their chemical design, pharmacological properties, radiolabeling, as well as preclinical and human PET imaging. In addition, this review addresses the current challenges for ECS PET biomarker development and highlights the important role of PET ligands to study disease pathophysiology as well as to facilitate drug discovery.
Title: Supplemental Choline Modulates Growth Performance and Gut Inflammation by Altering the Gut Microbiota and Lipid Metabolism in Weaned Piglets Qiu Y, Liu S, Hou L, Li K, Wang L, Gao K, Yang X, Jiang Z Ref: J Nutr, 151:20, 2021 : PubMed
BACKGROUND: Whether dietary choline and bile acids affect lipid use via gut microbiota is unclear. OBJECTIVES: This study aimed to investigate the effect of choline and bile acids on growth performance, lipid use, intestinal immunology, gut microbiota, and bacterial metabolites in weaned piglets. METHODS: A total of 128 weaned piglets [Duroc x (Landrace x Yorkshire), 21-d-old, 8.21 +/- 0.20 kg body weight (BW)] were randomly allocated to 4 treatments (8 replicate pens per treatment, each pen containing 2 males and 2 females; n = 32 per treatment) for 28 d. Piglets were fed a control diet (CON) or the CON diet supplemented with 597 mg choline/kg (C), 500 mg bile acids/kg (BA) or both (C + BA) in a 2 x 2 factorial design. Growth performance, intestinal function, gut microbiota, and metabolites were determined. RESULTS: Compared with diets without choline, choline supplementation increased BW gain (6.13%), average daily gain (9.45%), gain per feed (8.18%), jejunal lipase activity (60.2%), and duodenal IL10 gene expression (51%), and decreased the mRNA abundance of duodenal TNFA (TNFalpha) (40.7%) and jejunal toll-like receptor 4 (32.9%) (P < 0.05); additionally, choline increased colonic butyrate (29.1%) and the abundance of Lactobacillus (42.3%), while decreasing the bile acid profile (55.8% to 57.6%) and the abundance of Parabacteroides (75.8%), Bacteroides (80.7%), and unidentified-Ruminococcaceae (32.5%) (P >= 0.05). Compared with diets without BA, BA supplementation decreased the mRNA abundance of colonic TNFA (37.4%), NF-kappaB p65 (42.4%), and myeloid differentiation factor 88 (42.5%) (P >= 0.01); BA also increased colonic butyrate (20.9%) and the abundance of Lactobacillus (39.7%) and Faecalibacterium (71.6%) and decreased that of Parabacteroides (67.7%) (P < 0.05). CONCLUSIONS: Choline supplementation improved growth performance and prevented gut inflammation in weaned piglets by altering gut microbiota and lipid metabolism. BA supplementation suppressed intestinal inflammation with no effect on growth performance, which was associated with changed gut microbiota and metabolites.
Title: Clinical Evaluation and Test of a Modified Lp-PLA2 Kit in Diagnosing Atherosclerosis Yuan L, Hou L, Zhang L, Qin Z, Yu C Ref: Clin Lab, 67:, 2021 : PubMed
BACKGROUND: Lipoprotein-associated phospholipase A2 (Lp-PLA2) has been identified as an inflammatory marker tightly correlated with the onset of atherosclerosis. Although several methodologies have been developed to detect Lp-PLA2, including enzyme-linked immunosorbent assay, Lp-PLA2 detection is still time- and resource-consuming with poor antiinterference ability and low sensitivity. Thus, it is urgent to explore new methodology for Lp-PLA2 detection. METHODS: In the current study, we evaluated the clinical performance of a modified Lp-PLA2 quantitative assay kit based on magnetic particle chemiluminescence, and analyzed the levels of Lp-PLA2 in atherosclerosis patients using this kit. RESULTS: Our results showed that the magnetic particle chemiluminescence method could effectively dissociate Lp-PLA2 from lipoprotein and finish the test within 20 minutes with high accuracy and good repeatability, as demonstrated by the results of linear measurement range, precision, and recovery rate. Furthermore, our preliminary data revealed that serum Lp-PLA2 levels were correlated to the presence and degree of atherosclerotic plaques. CONCLUSIONS: Lp-PLA2 could be helpful in diagnosing atherosclerosis.
Title: A multifunctional bis-(-)-nor-meptazinol-oxalamide hybrid with metal-chelating property ameliorates Cu(II)-induced spatial learning and memory deficits via preventing neuroinflammation and oxido-nitrosative stress in mice Tan X, Zhou Y, Gong P, Guan H, Wu B, Hou L, Feng X, Zheng W, Li J Ref: J Trace Elem Med Biol, 52:199, 2019 : PubMed
Excess copper exposure is a risk factor of neurodegeneration related to Alzheimer's disease (AD). Evidence indicates that, besides promoting amyloid beta aggregation, activation of neuroinflammation and oxido-nitrosative stress (two key pathophysiological processes of AD) may also play important roles in Cu(II)-induced neuronal injury. Therefore, the copper-chelating strategy has gained attention in search for new anti-AD drugs. We previously reported a novel multifunctional compound N(1),N(2)-bis(3-(S)-meptazinol-propyl) oxalamide (ZLA), a bis-(-)-nor-meptazinol-oxalamide hybrid with properties of dual binding site acetylcholinesterase (AChE) inhibition and Cu(II)/Zn(II) chelation. The present study was aimed to explore its effect on cognitive deficits caused by intrahippocampal injection of Cu(II) in mice. Results showed that ZLA (2, 5 mg/kg; i.p.) treatment significantly ameliorated the Cu(II)-induced impairment of hippocampus-dependent learning and memory, whereas rivastigmine, an AChE inhibitor showing a similar potency of enzyme inhibition to ZLA, had no obvious effect. Immunohistochemical and Western blot analyses revealed that ZLA attenuated the decrease in hippocampal expression of microtubule-associated protein 2 (MAP2, a dendritic marker) in Cu(II)-challenged mice. Further analysis showed that ZLA suppressed the Cu(II)-evoked microglial activation. Moreover, it inhibited the Cu(II)-evoked production of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and IL-1beta and expression of inducible nitric oxide synthase in the hippocampus. The Cu(II)-induced oxidative and nitrosative stress in the hippocampus was also attenuated after ZLA treatment. Collectively, these results suggest that ZLA ameliorates the Cu(II)-caused cognitive deficits. Inhibition of neuroinflammation and oxido-nitrosative stress, and thus ameliorating neuronal injury, may be the potential mechanism for the anti-amnesic effect of ZLA.
Alzheimer's disease (AD) is the main type of dementia and is characterized by progressive memory loss and a notable decrease in cholinergic neuron activity. As classic drugs currently used in the clinic, acetylcholinesterase inhibitors (AChEIs) restore acetylcholine levels and relieve the symptoms of AD, but are insufficient at delaying the onset of AD. Based on the multi-target-directed ligand (MTDL) strategy, bis-(-)-nor-meptazinol (BIS-MEP) was developed as a multi-target AChEI that mainly targets AChE catalysis and the beta-amyloid (Abeta) aggregation process. In this study, we bilaterally injected Abeta oligomers and ibotenic acid (IBO) into the hippocampus of ICR mice and then subcutaneously injected mice with BIS-MEP to investigate its therapeutic effects and underlying mechanisms. According to the results from the Morris water maze test, BIS-MEP significantly improved the spatial learning and memory impairments in AD model mice. Compared with the vehicle control, the BIS-MEP treatment obviously inhibited the AChE activity in the mouse brain, consistent with the findings from the behavioral tests. The BIS-MEP treatment also significantly reduced the Abeta plaque area in both the hippocampus and cortex, suggesting that BIS-MEP represents a direct intervention for AD pathology. Additionally, the immunohistochemistry and ELISA results revealed that microglia (ionized calcium-binding adapter molecule 1, IBA1) and astrocyte (Glial fibrillary acidic protein, GFAP) activation and the secretion of relevant inflammatory factors (TNFalpha and IL-6) induced by Abeta were decreased by the BIS-MEP treatment. Furthermore, BIS-MEP showed more advantages than donepezil (an approved AChEI) as an Abeta intervention. Based on our findings, BIS-MEP improved spatial learning and memory deficits in AD mice by regulating acetylcholinesterase activity, Abeta deposition and the inflammatory response in the brain.
Fluoxetine is a selective serotonin reuptake inhibitor used as an antidepressant and has been frequently detected in aquatic environments. However, its effects in fish from Asia remain relatively less studied. In this study, the topmouth gudgeon Pseudorasbora parva was exposed to 0, 50, and 200microg/L of fluoxetine for 4h and 42 d. The effects of fluoxetine on biometrics were compared to biochemical endpoints indicative of stress in different fish tissues (brain, liver, gills and intestine) following exposures. In fish exposed for 42 d, lipid peroxidation endpoints were enhanced 80% in the liver and gills. Acetylcholinesterase (AChE) activity was increased 40% after exposure to 50microg/L and 55% at 200microg/L following 4h exposure. In contrast AChE was increased 26% (at 50microg/L) after 42 d of exposures. Enhanced ethoxyresorufin-O-deethylase activity (EROD) was detected only in fish exposed to 50microg/L of fluoxetine for 4h. The activity of alpha-glucosidase (alpha-Glu) was also induced (at 200microg/L) after 4h of exposure. After 4h of exposure, the activities of proteases in the intestine were generally inhibited at 200microg/L. Both 4h and 42 d exposures resulted in an increased hepatosomatic index (HSI) but did not affect the condition factor (CF). Our results demonstrate that fluoxetine significantly altered biochemical endpoints in P. parva after acute exposure and the morphological changes in liver size were not observed until 42d of exposure.
Title: The change of synovial fluid proteome in rabbit surgery-induced model of knee osteoarthritis Luo Q, Qin X, Qiu Y, Hou L, Yang N Ref: Am J Transl Res, 10:2087, 2018 : PubMed
The aims of this study were to explore the change of synovial fluid (SF) proteome in a knee osteoarthritis (KOA) rabbit model, and to provide a new target for the treatment of knee osteoarthritis at the proteomic level. Sixteen New Zealand rabbits were randomly and equally divided into two groups. Group A rabbits were subjected to right anterior cruciate ligament transection (ACLT), while group B rabbits were subjected to sham ACLT. Six weeks later, the proteomes of knee joint SF from group A and B rabbits were analyzed using a label-free quantitative proteomic analysis method. We extracted 944 relevant items from GO BlastGO2 for the 23 proteins differentially expressed between the two groups. The final annotation results were 23 protein sequences annotated by 462 GO items. According to the KEGG gene database of rabbit protein sequences, as well as annotation of the KO numbers of homologous/similar proteins to the relevant 64 KEGG pathways, we extracted the sequences of 16 significantly differently expressed proteins among the relevant 64 KEGG messages/metabolism pathways. These included adiponectin, pyruvate kinase, bisphosphoglycerate mutase, HtpG/heat shock proteins, hemoglobin subunit alpha-1 2, VCP (CDC48), 14-3-3 protein beta/theta/zeta, and ferritin heavy chain, whose levels were decreased in group A. The other proteins were fibrinogen alpha/beta/gamma chain, carboxylesterase 2, paraoxonase/arylesterase 1, apolipoprotein A-I, immunoglobulin heavy chain, and transferrin, whose levels were increased in group B. The identified differentially expressed proteins indicate the change of SF proteomic expression in KOA and may provide protein targets for treating this condition.
Background: Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative brain disorder, which is the most common form of dementia. Intensive efforts have been made to find effective and safe treatment against AD. Acetylcholinesterase inhibitors (AChEIs) have been widely used for the treatment of mild to moderate AD. In this study, we investigated the effect of Bis(9)-(-)-Meptazinol (B9M), a novel potential dual-binding acetylcholinesterase (AChE) inhibitor, on learning and memory abilities, as well as the underlying mechanism in the APP/PS1 mouse model of AD. Methods: B9M (0.1 mug/kg, 0.3 mug/kg, and 1 mug/kg) was administered by subcutaneous injection into eight-month-old APP/PS1 transgenic mice for four weeks. Morris water maze, nest-building and novel object recognition were used to examine learning and memory ability. Abeta levels and Abeta plaque were evaluated by ELISA and immunochemistry. Results: Our results showed that chronic treatment with B9M significantly improved the cognitive function of APP/PS1 transgenic mice in the Morris water maze test, nest-building test and novel object recognition test. Moreover, B9M improved cognitive deficits in APP/PS1 mice by a mechanism that may be associated with its inhibition of the AChE activity, Abeta plaque burden, levels of Abeta and the consequent activation of astrocytes and microglia in the brain of APP/PS1 transgenic mice. Most of important, the most effective dose of B9M in the present study is 1 mug/kg, which is one thousand of the dosage of Donepezil acted as the control treatment. Furthermore, B9M reduced Abeta plaque burden better than Donepezil. Conclusion: These results indicate that B9M appears to have potential as an effective AChE inhibitor for the treatment of AD with symptom-relieving and disease-modifying properties.
Title: Neurotrophins and cholinergic enzyme regulated by calpain-2: New insights into neuronal apoptosis induced by polybrominated diphenyl ether-153 Zhang H, Yang X, Li X, Zhang Z, Hou L, Wang Z, Niu Q, Wang T Ref: Toxicol Lett, 291:29, 2018 : PubMed
Polybrominated diphenyl ether-153 (BDE-153) has been demonstrated to induce neuronal apoptosis in rat cerebral cortex and primary neurons. Neurotrophins and cholinergic enzymes play critical roles in the neuronal survival, maintenance, synaptic plasticity and learning memory, however, their roles in neuronal apoptosis following the BDE-153 treatment remain unclear. In this study, we firstly explored the possible predominant pathway underlying the neuronal apoptotic induced by the BDE-153 treatment in rat cerebral cortex, by measuring expression levels (mRNA and protein) of p53, caspase-3, 8, 9, calpain-1, and calpain-2, detected the levels (protein contents and mRNA) of neurotrophins including brain-derived neurotrophic factor (BDNF), glial-derived neurotrophic factor (GDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and neurotrophin-4 (NT-4), and measured acetylcholinesterase (AchE) and choline acetyltransferase (ChaT) activities in rat cerebral cortex and primary neurons following BDE-153 treatment with or without pretreatment with inhibitors. Results showed that the neuronal apoptosis induced by BDE-153 was dependent on p53, and dependent on more calpain-2 than caspase-3 in the cerebral cortex of rats. Following the BDE-153 treatment, the protein contents and mRNA levels of BDNF, GDNF, NGF, NT-3, and NT-4, as well as the AchE and ChaT activities were significantly decreased in the cerebral cortex and primary neurons when compared to the untreated group. When pretreated primary neurons with calpain inhibitor PD150606 or cyclin-dependent kinase (cdk5, the downstream complex of calpain) inhibitor Roscovitine, the neurotrophins contents and activities of ChaT and AchE were reverted, along with the improvement of neuron survival compared with BDE-153 treatment alone. We conclude that neurotrophins and cholinergic enzymes were regulated by the calpain-2 activation and its downstream cdk5 pathway, and which was involved in the neuronal apoptosis induced by the BDE-153 treatment.
Title: Complete Genome Sequence of Pseudoxanthomonas suwonensis Strain J1, a Cellulose-Degrading Bacterium Isolated from Leaf- and Wood-Enriched Soil Hou L, Jiang J, Xu Z, Zhou Y, Leung FC Ref: Genome Announc, 3:, 2015 : PubMed
We report here the complete genome sequence of the cellulose-degrading bacterium Pseudoxanthomonas suwonensis strain J1, isolated from soil enriched with rotten leaves and wood from the Zhong Mountain Scenic Area in Nanjing, China. This complete genome may contribute to further investigation of plant biomass degradation.
Strigolactones (SLs) are endogenous hormones and exuded signaling molecules in plant responses to low levels of mineral nutrients. Key mediators of the SL signaling pathway in rice include the alpha/beta-fold hydrolase DWARF 14 (D14) and the F-box component DWARF 3 (D3) of the ubiquitin ligase SCF(D3) that mediate ligand-dependent degradation of downstream signaling repressors. One perplexing feature is that D14 not only functions as the SL receptor but is also an active enzyme that slowly hydrolyzes diverse natural and synthetic SLs including GR24, preventing the crystallization of a binary complex of D14 with an intact SL as well as the ternary D14/SL/D3 complex. Here we overcome these barriers to derive a structural model of D14 bound to intact GR24 and identify the interface that is required for GR24-mediated D14-D3 interaction. The mode of GR24-mediated signaling, including ligand recognition, hydrolysis by D14, and ligand-mediated D14-D3 interaction, is conserved in structurally diverse SLs. More importantly, D14 is destabilized upon the binding of ligands and D3, thus revealing an unusual mechanism of SL recognition and signaling, in which the hormone, the receptor, and the downstream effectors are systematically destabilized during the signal transduction process.
Title: Microsomal epoxide hydrolase (EPHX1) polymorphisms are associated with aberrant promoter methylation of ERCC3 and hematotoxicity in benzene-exposed workers Xing C, Chen Q, Li G, Zhang L, Zheng M, Zou Z, Hou L, Wang QF, Liu X, Guo X Ref: Environmental & Molecular Mutagenesis, 54:397, 2013 : PubMed
Benzene is an important industrial chemical and widespread environmental pollutant known to induce leukemia and other blood disorders. To be carcinogenic, benzene must be metabolized to produce toxic metabolites. To investigate whether single nucleotide polymorphisms (SNPs) in the metabolic enzyme genes are associated with benzene-induced alterations in DNA methylation and hematotoxicity, we genotyped four commonly studied SNPs in three metabolic enzymes genes CYP1A1, EPHX1 and NQO1; and analyzed promoter DNA methylation status in 11 genes which have been reported to be associated with benzene-induced hematotoxicity (BLM, CYP1A1, EPHX1, ERCC3, NQO1, NUDT1, p15, p16, RAD51, TP53 and WRAP53) in 77 benzene-exposed workers and 25 unexposed controls in China. ERCC3, a DNA repair gene, showed a small but statistically significant increase of promoter DNA methylation in the exposed group compared with the unexposed group (mean +/- SD: 4.73 +/- 3.46% vs. 3.63 +/- 1.96%, P = 0.048). We also observed that an increased number of C allele for rs1051740 in EPHX1 was associated with decreased ERCC3 methylation levels in benzene-exposed workers (P(trend) = 0.001), but not in unexposed controls (P(trend) = 0.379). Interestingly, another EPHX1 SNP (rs2234922) was associated with lower white blood cell (WBC) counts (P(trend) = 0.044) in benzene-exposed workers. These associations remained the same when ERCC3 promoter methylation and WBCs were dichotomized according to the 90th percentile (>/=6%) of methylation levels in controls and a leucopenia cutoff (<4 x 10(9) /L), respectively. Our findings suggest that benzene exposure may be associated with hypermethylation in ERCC3, and that genetic variants in EPHX1 may play an important role in epigenetic changes and hematotoxicity among benzene-exposed workers.
Title: Characterization of a new and thermostable esterase from a metagenomic library Zhu Y, Li J, Cai H, Ni H, Xiao A, Hou L Ref: Microbiol Res, 168:589, 2013 : PubMed
A new gene encoding an esterase (designated as EstEP16) was identified from a metagenomic library prepared from a sediment sample collected from a deep-sea hydrothermal field in east Pacific. The open reading frame of this gene encoded 249 amino acid residues. It was cloned, overexpressed in Escherichia coli, and the recombinant protein was purified to homogeneity. The monomeric EstEP16 presented a molecular mass of 51.7kDa. Enzyme assays using p-nitrophenyl esters with different acyl chain lengths as the substrates confirmed its esterase activity, yielding highest specific activity with p-nitrophenyl acetate. When p-nitrophenyl butyrate was used as a substrate, recombinant EstEP16 exhibited highest activity at pH 8.0 and 60 degrees C. The recombinant enzyme retained about 80% residual activity after incubation at 90 degrees C for 6h, which indicated that EstEP16 was thermostable. Homology modeling of EstEP16 was developed with the monoacylglycerol lipase from Bacillus sp. H-257 as a template. The structure showed an alpha/beta-hydrolase fold and indicated the presence of a typical catalytic triad. The activity of EstEP16 was inhibited by addition of phenylmethylsulfonyl fluoride, indicating that it contains serine residue, which plays a key role in the catalytic mechanism.
Aspergillus oryzae is the most important fungus for the traditional fermentation in China and is particularly important in soy sauce fermentation. We report the 36,547,279-bp draft genome sequence of A. oryzae 3.042 and compared it to the published genome sequence of A. oryzae RIB40.
Title: Associations of PLA2G7 gene polymorphisms with plasma lipoprotein-associated phospholipase A2 activity and coronary heart disease in a Chinese Han population: the Beijing atherosclerosis study Hou L, Chen S, Yu H, Lu X, Chen J, Wang L, Huang J, Fan Z, Gu D Ref: Hum Genet, 125:11, 2009 : PubMed
The human PLA2G7 gene encodes lipoprotein-associated phospholipase A(2) (Lp-PLA(2)), an emerging risk factor for cardiovascular diseases. In the present study, seven single nucleotide polymorphisms (SNPs) in the PLA2G7 gene were genotyped in 827 patients with coronary heart disease (CHD), of which 512 were patients with myocardial infarction (MI), and 947 age- and gender-matched controls in a Chinese Han population. Plasma Lp-PLA(2) activity was measured in 416 randomly selected controls and 689 randomly selected CHD patients, including 423 MI patients. Lp-PLA(2) activity in CHD and MI cases was significantly higher (233.42+/-57.66 and 234.27+/-59.51 nmol ml(-1) min(-1), respectively) than in controls (211.47+/-58.61 nmol ml(-1) min(-1)). After adjusting for traditional risk factors by logistic regression, the odds ratios for CHD and MI per 1 standard deviation increment of Lp-PLA(2) activity were 1.27 (95% CI, 1.07-1.50) and 1.27 (95% CI, 1.05-1.54), respectively. Both single SNP analysis and haplotype analysis showed that the V279F and I198T polymorphisms were significantly associated with the reduced Lp-PLA(2) activity, but neither was associated with increased CHD risk. Both univariate and multivariate analyses, adjusting effects of conventional factors, indicated that the rs13210554 T allele increased the risk of MI in this Chinese Han population. In summary, an independent association of increased plasma Lp-PLA(2) activity with CHD and MI existed in this Chinese Han Population. Although V279F and I198T mutations significantly decreased the activity of Lp-PLA(2), only the promoter rs13210554 polymorphism was associated with MI. Lp-PLA(2) activity appears to influence the CHD and MI risk in Chinese Han population.
African trypanosomes cause human sleeping sickness and livestock trypanosomiasis in sub-Saharan Africa. We present the sequence and analysis of the 11 megabase-sized chromosomes of Trypanosoma brucei. The 26-megabase genome contains 9068 predicted genes, including approximately 900 pseudogenes and approximately 1700 T. brucei-specific genes. Large subtelomeric arrays contain an archive of 806 variant surface glycoprotein (VSG) genes used by the parasite to evade the mammalian immune system. Most VSG genes are pseudogenes, which may be used to generate expressed mosaic genes by ectopic recombination. Comparisons of the cytoskeleton and endocytic trafficking systems with those of humans and other eukaryotic organisms reveal major differences. A comparison of metabolic pathways encoded by the genomes of T. brucei, T. cruzi, and Leishmania major reveals the least overall metabolic capability in T. brucei and the greatest in L. major. Horizontal transfer of genes of bacterial origin has contributed to some of the metabolic differences in these parasites, and a number of novel potential drug targets have been identified.
Whole-genome sequencing of the protozoan pathogen Trypanosoma cruzi revealed that the diploid genome contains a predicted 22,570 proteins encoded by genes, of which 12,570 represent allelic pairs. Over 50% of the genome consists of repeated sequences, such as retrotransposons and genes for large families of surface molecules, which include trans-sialidases, mucins, gp63s, and a large novel family (>1300 copies) of mucin-associated surface protein (MASP) genes. Analyses of the T. cruzi, T. brucei, and Leishmania major (Tritryp) genomes imply differences from other eukaryotes in DNA repair and initiation of replication and reflect their unusual mitochondrial DNA. Although the Tritryp lack several classes of signaling molecules, their kinomes contain a large and diverse set of protein kinases and phosphatases; their size and diversity imply previously unknown interactions and regulatory processes, which may be targets for intervention.
