Lee SE

References (15)

Title : GABAergic-like dopamine synapses in the brain - Kim_2023_Cell.Rep_42_113239
Author(s) : Kim HJ , Hwang B , Reva M , Lee J , Lee BE , Lee Y , Cho EJ , Jeong M , Lee SE , Myung K , Baik JH , Park JH , Kim JI
Ref : Cell Rep , 42 :113239 , 2023
Abstract : Dopamine synapses play a crucial role in volitional movement and reward-related behaviors, while dysfunction of dopamine synapses causes various psychiatric and neurological disorders. Despite this significance, the true biological nature of dopamine synapses remains poorly understood. Here, we show that dopamine transmission is strongly correlated with GABA co-transmission across the brain and dopamine synapses are structured and function like GABAergic synapses with marked regional heterogeneity. In addition, GABAergic-like dopamine synapses are clustered on the dendrites, and GABA transmission at dopamine synapses has distinct physiological properties. Interestingly, the knockdown of neuroligin-2, a key postsynaptic protein at GABAergic synapses, unexpectedly does not weaken GABA co-transmission but instead facilitates it at dopamine synapses in the striatal neurons. More importantly, the attenuation of GABA co-transmission precedes deficits in dopaminergic transmission in animal models of Parkinson's disease. Our findings reveal the spatial and functional nature of GABAergic-like dopamine synapses in health and disease.
ESTHER : Kim_2023_Cell.Rep_42_113239
PubMedSearch : Kim_2023_Cell.Rep_42_113239
PubMedID: 37819757

Title : Combined toxicity of endosulfan and phenanthrene mixtures and induced molecular changes in adult Zebrafish (Danio rerio) - Kim_2017_Chemosphere_194_30
Author(s) : Kim K , Jeon HJ , Choi SD , Tsang DCW , Oleszczuk P , Ok YS , Lee HS , Lee SE
Ref : Chemosphere , 194 :30 , 2017
Abstract : Individual and combined toxicities of endosulfan (ENDO) with phenanthrene (PHE) were evaluated using zebrafish (Danio rerio) adults. The 96-h LC50 values for ENDO and PHE were 4.6 mug L(-1) and 920 mug L(-1), respectively. To evaluate the mixture toxicity, LC10 and LC50 concentrations were grouped into four combinations as ENDO-LC10 + PHE-LC10, ENDO-LC10 + PHE-LC50, ENDO-LC50 + PHE-LC10, and ENDO-LC50 + PHE-LC50, and their acute toxicities were determined. The combination of LC50-ENDO and LC10-PHE exhibited a synergistic effect. In addition, acetylcholinesterase activity decreased in zebrafish bodies exposed to ENDO with or without PHE. Combined treatments induced higher glutathione S-transferase activity compared to individual treatments. Carboxylesterase activity increased in both heads and bodies of ENDO-treated fishes compared with PHE-treated fishes. Using RT-qPCR technique, CYP1A gene expression significantly up-regulated in all combinations, whereas CYP3A was unchanged, suggesting that enzymes involved in defense may play different roles in the detoxification. CYP7A1 gene responsible for bile acid biosynthesis is dramatically down-regulated after exposure to the synergistic combination exposure, referring that the synergistic effect may be resulted from the reduction of bile production in zebrafishes. Among gender-related genes, CYP11A1 and CYP17A1 genes in female zebrafish decreased after treatment with ENDO alone and combination of LC50-ENDO and LC10-PHE. This might be related to a reduction in cortisol production. The overall results indicated that ENDO and PHE were toxic to zebrafish adults both individually and in combination, and that their co-presence induced changes in the expression of genes responsible for metabolic processes and defense mechanisms.
ESTHER : Kim_2017_Chemosphere_194_30
PubMedSearch : Kim_2017_Chemosphere_194_30
PubMedID: 29197246

Title : New reference genome sequences of hot pepper reveal the massive evolution of plant disease-resistance genes by retroduplication - Kim_2017_Genome.Biol_18_210
Author(s) : Kim S , Park J , Yeom SI , Kim YM , Seo E , Kim KT , Kim MS , Lee JM , Cheong K , Shin HS , Kim SB , Han K , Lee J , Park M , Lee HA , Lee HY , Lee Y , Oh S , Lee JH , Choi E , Lee SE , Jeon J , Kim H , Choi G , Song H , Lee SC , Kwon JK , Koo N , Hong Y , Kim RW , Kang WH , Huh JH , Kang BC , Yang TJ , Lee YH , Bennetzen JL , Choi D
Ref : Genome Biol , 18 :210 , 2017
Abstract : BACKGROUND: Transposable elements are major evolutionary forces which can cause new genome structure and species diversification. The role of transposable elements in the expansion of nucleotide-binding and leucine-rich-repeat proteins (NLRs), the major disease-resistance gene families, has been unexplored in plants. RESULTS: We report two high-quality de novo genomes (Capsicum baccatum and C. chinense) and an improved reference genome (C. annuum) for peppers. Dynamic genome rearrangements involving translocations among chromosomes 3, 5, and 9 were detected in comparison between C. baccatum and the two other peppers. The amplification of athila LTR-retrotransposons, members of the gypsy superfamily, led to genome expansion in C. baccatum. In-depth genome-wide comparison of genes and repeats unveiled that the copy numbers of NLRs were greatly increased by LTR-retrotransposon-mediated retroduplication. Moreover, retroduplicated NLRs are abundant across the angiosperms and, in most cases, are lineage-specific. CONCLUSIONS: Our study reveals that retroduplication has played key roles for the massive emergence of NLR genes including functional disease-resistance genes in pepper plants.
ESTHER : Kim_2017_Genome.Biol_18_210
PubMedSearch : Kim_2017_Genome.Biol_18_210
PubMedID: 29089032
Gene_locus related to this paper: capch-q75qh4 , capan-a0a1u8fuf5 , capan-a0a1u8gmz3 , capch-a0a2g3bqp0 , capba-a0a2g2vcw4 , capan-a0a1u8flz5 , capch-a0a2g3bau3 , capch-a0a2g3b6c0 , capan-a0a2g2y016 , capch-a0a2g3cje8 , capba-a0a2g2xr67 , capan-a0a1u8fpc9 , capan-a0a1u8fqs3 , capan-a0a1u8ft99 , capan-a0a2g2xtt0 , capan-a0a1u8eu02 , capan-a0a1u8hd13 , capan-a0a2g2y0b6

Title : Chlorpyrifos-induced biomarkers in Japanese medaka (Oryzias latipes) - Jeon_2016_Environ.Sci.Pollut.Res.Int_23_1071
Author(s) : Jeon HJ , Lee YH , Mo HH , Kim MJ , Al-Wabel MI , Kim Y , Cho K , Kim TW , Ok YS , Lee SE
Ref : Environ Sci Pollut Res Int , 23 :1071 , 2016
Abstract : Chlorpyrifos (CHL) is an organophosphate compound that is widely used as an insecticide. Due to its repeated use and high environmental residual property, CHL is frequently passed into aquatic environments by runoff. Consequently, there may be an adverse effect on aquatic vertebrate animals, including fish. Therefore, in this study, we assessed how CHL affected Japanese medaka (Oryzias latipes). The acute toxicity of CHL in adult fish after 96 h of exposure was determined to be 212.50, 266.79, and 412.28 mug L(-1) (LC25, LC50, and LC95, respectively). Acetylcholinesterase (AChE), glutathione S-transferase (GST), and carboxylesterase (CE) activities were obtained from the livers of dead or surviving fish, and the results showed 4.8-fold lower, 4.5-fold higher, and 18.6-fold lower activities for the AChE, GST, and CE, respectively, for 64-h exposure at a concentration of 400 mug L(-1) of CHL. In the embryo toxicity test, curved spines were observed in embryos that were exposed to CHL for 48 h in a concentration-dependent manner. With identification of biomarkers for CHL in the fish, two protein peaks, 5550.86 and 5639.79 m/z, were found to be upregulated. These two proteins can be used as protein biomarkers for CHL contamination in aquatic systems. A phosphatidyl choline with an m/z ratio of 556.32 dramatically decreased after CHL exposure in the fish; thus, it may be considered as a lipid biomarker for CHL. It is assumed as the first report to identify a phospholipid biomarker using a lipidomics approach in fish toxicology. Taken together, these results demonstrated the adverse effects of CHL on Japanese medaka and reveal several candidate biomarkers that can be used as diagnostic tools for determining CHL.
ESTHER : Jeon_2016_Environ.Sci.Pollut.Res.Int_23_1071
PubMedSearch : Jeon_2016_Environ.Sci.Pollut.Res.Int_23_1071
PubMedID: 25966881

Title : Integrated biomarkers induced by chlorpyrifos in two different life stages of zebrafish (Danio rerio) for environmental risk assessment - Jeon_2016_Environ.Toxicol.Pharmacol_43_166
Author(s) : Jeon HJ , Lee YH , Kim MJ , Choi SD , Park BJ , Lee SE
Ref : Environ Toxicol Pharmacol , 43 :166 , 2016
Abstract : This study was performed to understand how chlorpyrifos (CHL) affects zebrafish (Danio rerio) embryos and adults, by exposing this model organism to various concentrations of the insecticide. The 96-h acute toxicity test to determine the effect of CHL on adult zebrafish yielded a LC50 of 709.43mug/L-1. Small molecular weight proteins less than 25kDa and phospholipids were analyzed with MALDI-TOF MS/MS in order to compare expression patterns, revealing that some peaks were dramatically altered after CHL treatment. Whereas no acute toxicity was detected in the embryo toxicity test, malformation of zebrafish larvae was observed, with many individuals harboring curved spines. In an angiogenesis test on larvae of transgenic zebrafish, CHL did not have an inhibitory effect. Relative gene expression analyses using real-time polymerase chain reaction (RT-PCR) of DNA from zebrafish embryos revealed that different subtypes of cytochrome P450 (CYP450), such as CYP1A and CYP3A, were significantly up-regulated in response to CHL at a concentration of 400mug/L-1 compared to the control. The expression level of NR1I2, a CYP gene transcriptional regulator, UGT1a1, and MDR1 were all up-regulated in the CHL-treated embryos. Finally, the expression level of acetylcholinesterase (AChE) and catalase (CAT) decreased, whereas that of superoxide dismutase (SOD) did not differ significantly. Our results suggest that the up-regulation of metabolic enzymes including CYP450 and MDR1 may be involved in CHL resistance in zebrafish.
ESTHER : Jeon_2016_Environ.Toxicol.Pharmacol_43_166
PubMedSearch : Jeon_2016_Environ.Toxicol.Pharmacol_43_166
PubMedID: 26998704

Title : Interpretation and estimation for dynamic mobility of chlorpyrifos in soils containing different organic matters - Hwang_2015_Environ.Geochem.Health_37_1017
Author(s) : Hwang JI , Lee SE , Kim JE
Ref : Environ Geochem Health , 37 :1017 , 2015
Abstract : The adsorption and removal behaviors of the organophosphate insecticide chlorpyrifos in two soils (AS and GW soils) with different organic matter contents were investigated to predict the dynamic residues in the soil environment. The adsorption test showed that the chlorpyrifos adsorptive power for the AS soil containing high organic matter content was greater than that for the GW soil. The extent of the time-dependent removal of chlorpyrifos in the tested soils was not significantly different except at 90 days after the treatment. The availability of a chemical-specific residue model developed in this study was statistically assessed to estimate the chlorpyrifos residue in soil solutions that could be absorbed into plants. The values modeled using the soil experimental data were satisfactory, having a mean deviation of 32 % from the measured data. The correlation between the modeled and measured data was acceptable, with mean coefficients of correlation (R (2)) of 0.89. Furthermore, the average of the residual error was low at 0.43, which corresponded to a mean factor of -1.9. The developed model could be used as a critical tool to predict the subsequent plant uptake of chlorpyrifos.
ESTHER : Hwang_2015_Environ.Geochem.Health_37_1017
PubMedSearch : Hwang_2015_Environ.Geochem.Health_37_1017
PubMedID: 26055453

Title : Highly selective biomarkers for pesticides developed in Eisenia fetida using SELDI-TOF MS - Park_2015_Environ.Toxicol.Pharmacol_39_635
Author(s) : Park DS , Jeon HJ , Park ES , Bae IK , Kim YE , Lee SE
Ref : Environ Toxicol Pharmacol , 39 :635 , 2015
Abstract : The repeated use of pesticides, and their subsequent residues, has contributed to severe adverse effects on the environment, including risks to human health. Therefore, it is important to assess the quality of the environment to ensure it remains free from pesticide residues. The six pesticides tested in this study showed high mortality on Eisenia fetida with LC50 values ranging from 7.7 to 37.9gL-1. The strongest lethal effect resulted from the organochlorine insecticide endosulfan (LC50=7.7gL-1). Following exposure to the carbamate pesticides, acetylcholinesterase activity in E. fetida decreased dramatically in comparison to the control. Carboxylesterase activity was only lowered in E. fetida exposed to propoxur, when compared to the control. The remaining five pesticides had no significant effect on carboxylesterase activity in E. fetida. In order to discover pesticide-specific biomarkers with differentially expressed proteins after exposure to pesticides, protein patterns of pesticide-treated E. fetida were analyzed using SELDI-TOF MS with Q10 ProteinChips. Protein patterns were compared with their intensities at the same mass-to-charge ratios (m/z). All 42 peaks had intensities with associated p-values less than 0.089, and 40 of these peaks had associated p-values of 0.05. Using SELDI-TOF MS technology, selective biomarkers for the six pesticides tested were found in E. fetida; four proteins with 5425, 5697, 9523, and 9868 m/z were consistently observed in the earthworms following exposure to the carbamates.
ESTHER : Park_2015_Environ.Toxicol.Pharmacol_39_635
PubMedSearch : Park_2015_Environ.Toxicol.Pharmacol_39_635
PubMedID: 25682009

Title : Determination of biomarkers for polycyclic aromatic hydrocarbons (PAHs) toxicity to earthworm (Eisenia fetida) - Nam_2015_Environ.Geochem.Health_37_943
Author(s) : Nam TH , Jeon HJ , Mo HH , Cho K , Ok YS , Lee SE
Ref : Environ Geochem Health , 37 :943 , 2015
Abstract : Polycyclic aromatic hydrocarbon (PAH) compounds are persistent, carcinogenic, and mutagenic. When PAHs enter agricultural soils through sewage sludge, they pose an environmental risk to soil organisms, including earthworms. Therefore, we aimed to determine the toxic effects of PAHs on earthworms. Five PAHs were used: fluorene, anthracene, phenanthrene, fluoranthene, and pyrene. Only fluorene and phenanthrene exhibited toxicity (LC50 values 394.09 and 114.02 g L(-1), respectively) against the earthworm Eisenia fetida. None of the other PAHs tested in this study enhanced the mortality of adult earthworm until the concentrations reached to 1000 g L(-1). After exposure to PAHs, acetylcholinesterase (AChE) activity in E. fetida decreased in a concentration-dependent manner, and phenanthrene exhibited the strongest inhibitory effect on AChE, followed by fluorene. Activity of a representative detoxifying enzyme, carboxylesterase, was dramatically reduced in E. fetida exposed to all tested PAHs in comparison with that observed in the control test. The remaining glutathione S-transferase activity significantly decreased in E. fetida after exposure to PAHs. To profile small proteins <20 kDa, SELDI-TOF MS with Q10 ProteinChips was used, and 54 proteins were identified as being significantly different from the control (p = 0.05). Among them, the expressions of three proteins at 4501.8, 4712.4, and 4747.9 m/z were only enhanced in E. fetida exposed to anthracene and pyrene. One protein with 16,174 m/z was selectively expressed in E. fetida exposed to fluorene, phenanthrene, and fluoranthene. These proteins may be potential biomarkers for the five PAHs tested in E. fetida.
ESTHER : Nam_2015_Environ.Geochem.Health_37_943
PubMedSearch : Nam_2015_Environ.Geochem.Health_37_943
PubMedID: 25920560

Title : Improvements in memory after medial septum stimulation are associated with changes in hippocampal cholinergic activity and neurogenesis - Jeong_2014_Biomed.Res.Int_2014_568587
Author(s) : Jeong da U , Lee JE , Lee SE , Chang WS , Kim SJ , Chang JW
Ref : Biomed Res Int , 2014 :568587 , 2014
Abstract : Deep brain stimulation (DBS) has been found to have therapeutic effects in patients with dementia, but DBS mechanisms remain elusive. To provide evidence for the effectiveness of DBS as a treatment for dementia, we performed DBS in a rat model of dementia with intracerebroventricular administration of 192 IgG-saporins. We utilized four groups of rats, group 1, unlesioned control; group 2, cholinergic lesion; group 3, cholinergic lesion plus medial septum (MS) electrode implantation (sham stimulation); group 4, cholinergic lesions plus MS electrode implantation and stimulation. During the probe test in the water maze, performance of the lesion group decreased for measures of time spent and the number of swim crossings over the previous platform location. Interestingly, the stimulation group showed an equivalent performance to the normal group on all measures. And these are partially reversed by the electrode implantation. Acetylcholinesterase activity in the hippocampus was decreased in lesion and implantation groups, whereas activity in the stimulation group was not different from the normal group. Hippocampal neurogenesis was increased in the stimulation group. Our results revealed that DBS of MS restores spatial memory after damage to cholinergic neurons. This effect is associated with an increase in hippocampal cholinergic activity and neurogenesis.
ESTHER : Jeong_2014_Biomed.Res.Int_2014_568587
PubMedSearch : Jeong_2014_Biomed.Res.Int_2014_568587
PubMedID: 25101288

Title : Acute colonic pseudo-obstruction following allogeneic stem cell transplantation successfully treated by neostigmine - Yahng_2013_Blood.Res_48_145
Author(s) : Yahng SA , Yoon JH , Shin SH , Lee SE , Eom KS , Kim YJ
Ref : Blood Res , 48 :145 , 2013
Abstract : Acute colonic pseudo-obstruction (ACPO), also known as Ogilvie's syndrome, is a rare clinical syndrome of massive large bowel dilatation without mechanical obstruction, which may cause significant morbidity and mortality. Treatment focuses on decompressing a severely dilated colon. The proposed theory that this severe ileus results from an imbalance in the autonomous regulation of colonic movement supports the rationale for using neostigmine, a reversible acetylcholinesterase inhibitor, in patients who failed conservative care. Although gastrointestinal complications are frequent following allogeneic stem cell transplantation (SCT), the incidence of ACPO in a transplant setting is unknown and, if not vigilant, this adynamic ileus can be underestimated. We describe the case of a patient with myelodysplastic syndrome undergoing non-myeloablative allogeneic SCT from a partially human leukocyte antigen-mismatched sibling donor, and whose clinical course was complicated by ACPO in the early post-engraftment period. The ileus was not associated with gut graft-versus-host disease or infectious colitis. After 3 days of conservative care, intravenous neostigmine (2 mg/day) was administered for 3 consecutive days. Symptoms and radiologic findings began to improve 72 hours after the initial injection of neostigmine, and complete response without any associated complications was achieved within a week. Thus, neostigmine can be a safe medical therapy with successful outcome for patients who develop ACPO following allogeneic SCT.
ESTHER : Yahng_2013_Blood.Res_48_145
PubMedSearch : Yahng_2013_Blood.Res_48_145
PubMedID: 23826585

Title : Complete genome sequencing of Lactobacillus acidophilus 30SC, isolated from swine intestine - Oh_2011_J.Bacteriol_193_2882
Author(s) : Oh S , Roh H , Ko HJ , Kim S , Kim KH , Lee SE , Chang IS , Choi IG
Ref : Journal of Bacteriology , 193 :2882 , 2011
Abstract : Lactobacillus acidophilus 30SC has been isolated from swine intestines and considered a probiotic strain for dairy products because of its ability to assimilate cholesterol and produce bacteriocins. Here, we report the complete genome sequence of Lactobacillus acidophilus 30SC (2,078,001 bp) exhibiting strong acid resistance and enhanced bile tolerance.
ESTHER : Oh_2011_J.Bacteriol_193_2882
PubMedSearch : Oh_2011_J.Bacteriol_193_2882
PubMedID: 21478365
Gene_locus related to this paper: lache-pepx , lache-prolinase

Title : A patient with Churg-Strauss syndrome who underwent endoscopic sinus surgery under general anesthesia -A case report - Im_2010_Korean.J.Anesthesiol_59_49
Author(s) : Im HS , Cho KR , Shin CM , Kim YJ , Choe YK , Cheong SH , Lee KM , Lee JH , Lim SH , Kim YH , Lee SE
Ref : Korean J Anesthesiol , 59 :49 , 2010
Abstract : There are many cause of cholinesterase deficiency, including drugs, liver disease, chronic anemia, malignant states, cardiac failure, severe acute infection, surgical shock, severe burn, collagen disease and vasculitis syndromes. Vasculitis syndromes are relatively rare, and among them, Churg-Strauss syndrome (CSS) is even rarer. We report here on a case of a patient with CSS who underwent endoscopic sinus surgery under general anesthesia.
ESTHER : Im_2010_Korean.J.Anesthesiol_59_49
PubMedSearch : Im_2010_Korean.J.Anesthesiol_59_49
PubMedID: 20651999

Title : Esterase Activity and Resistance to Organophosphorus Insecticides in Larvae of Oryzaephilus surinamensis (L) (Coleoptera: Silvanidae) - Park_2002_J.Asia.Pac.Entomol_5_161
Author(s) : Park EK , Choi IW , Lee SE
Ref : Journal of Asia-Pacific Entomology , 5 :161 , 2002
Abstract : Acetylcholinesterase and carboxylesterase activities of four strains of Oryzaephilus surinamensis (L.) larvae were examined. The three strains of VOS49, VOSF, and VOSCM were resistant to malathion, fenitrothion, and chlorpyrifos-methyl, respectively, while VOS48 was a susceptible strain. Cross-resistance to all three organophosphate insecticides tested was confirmed in larvae of the three resistant strains. Acetylcholinesterase activity was not correlated to organophosphate resistance in those resistant strains. VOS49, VOSF and VOSCM showed enhanced levels of carboxylesterase activity based on p-nitrophenyl acetate, +/--naphthyl acetate, or beta-naphthyl acetate substrates. However, these activities were significantly lower than those of O. surinamensis adults. PAGE zymograms showed major differences in carboxylesterase band pattern among strains. VOS49 carboxylesterase banding pattern was significantly different from other two resistant strains. Interestingly, these larval esterase band patterns were very similar to those of O. surinamensis adults. Therefore, carboxylesterase activity of O. surinamensis plays important role in resistance to organophosphate insecticide from larval stage.
ESTHER : Park_2002_J.Asia.Pac.Entomol_5_161
PubMedSearch : Park_2002_J.Asia.Pac.Entomol_5_161

Title : Fumigant toxicity of volatile natural products from Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae (L) - Lee_2001_Pest.Manag.Sci_57_548
Author(s) : Lee SE , Lee BH , Choi WS , Park BS , Kim JG , Campbell BC
Ref : Pest Manag Sci , 57 :548 , 2001
Abstract : The fumigant toxicity of various volatile constituents of essential oils extracted from sixteen Korean spices and medicinal plants towards the rice weevil, Sitophilus oryzae L (Coleoptera: Curculionidae), was determined. The most potent toxicity was found in the essential oil from Mentha arvensis L. var piperascens (LC50 = 45.5 microliters litre-1 air). GC-MS analysis of essential oil from M arvensis showed it to be rich in menthol (63.2%), menthone (13.1%) and limonene (1.5%), followed in abundance by beta-pinene (0.7%), alpha-pinene (0.6%) and linalool (0.2%). Treatment of S oryzae with each of these terpenes showed menthone to be most active (LC50 = 12.7 microliters litre-1 air) followed by linalool (LC50 = 39.2 microliters litre-1 air) and alpha-pinene (LC50 = 54.9 microliters litre-1 air). Studies on inhibition of acetylcholinesterase activity of S oryzae showed menthone to have a nine-fold lower inhibitory effect than menthol, despite menthone being 8.1-fold more toxic than menthol to the rice weevil. Different modes of toxicity of these monoterpenes towards S oryzae are discussed.
ESTHER : Lee_2001_Pest.Manag.Sci_57_548
PubMedSearch : Lee_2001_Pest.Manag.Sci_57_548
PubMedID: 11407032

Title : Biochemical mechanisms of resistance in strains of Oryzaephilus surinamensis (Coleoptera: Silvanidae) resistant to malathion and chlorpyrifos-methyl - Lee_2001_J.Econ.Entomol_94_706
Author(s) : Lee SE , Lees EM
Ref : J Econ Entomol , 94 :706 , 2001
Abstract : The acetylcholinesterase, carboxylesterase, and cytochrome P450 monooxygenase activities of three strains of Oryzaephilus srinamensis (L.) were examined to better understand biochemical mechanisms of resistance. The three strains were VOS49 and VOSCM, selected for resistance to malathion and chlorpyrifos-methyl, respectively, and VOS48, a standard susceptible strain. Cross-resistance to malathion and chlorpyrifos-methyl was confirmed in VOS49 and VOSCM. Acetylcholinesterase activity was not correlated to resistance among these strains. VOS49 and VOSCM showed elevated levels of carboxylesterase activity based on p-nitrophenylacetate, alpha-naphthyl acetate, or beta-naphthyl acetate substrates. PAGE zymograms showed major differences in caboxylesterase isozyme banding among strains. VOSCM had one strongly staining isozyme band. A band having the same Rf-value was very faint in VOS48. The VOS49 carboxylesterase banding pattern was different from both VOSCM and VOS48. Cytochrome P450 monooxygenase activity was based on cytochrome P450 content, aldrin epoxidase activity, and oxidation of organophosphate insecticides, all elevated in resistant strains. The monooxygenase activity varied with insecticide substrate and resistant strain, suggesting specific cytochromes P450 may exist for different insecticides. The monooxygenase activity of the VOS49 strain was much higher with malathion than chlorpyrifos-methyl as substrates, whereas VOSCM monooxygenase activity was higher with malathion than chlorpyrifos-methyl as substrates. Results are discussed in the context of resistance mechanisms to organophosphate insecticides in O. surinamensis.
ESTHER : Lee_2001_J.Econ.Entomol_94_706
PubMedSearch : Lee_2001_J.Econ.Entomol_94_706
PubMedID: 11425027