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Genomic Insights into the Glutathione S-Transferase Gene Family of Two Rice Planthoppers, Nilaparvata lugens (St?l) and Sogatella furcifera (Horváth) (Hemiptera: Delphacidae)  [PDF]
Wen-Wu Zhou, Qing-Mei Liang, Yi Xu, Geoff M. Gurr, Yan-Yuan Bao, Xue-Ping Zhou, Chuan-Xi Zhang, Jiaan Cheng, Zeng-Rong Zhu
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0056604
Abstract: Background Glutathione S-transferase (GST) genes control crucial traits for the metabolism of various toxins encountered by insects in host plants and the wider environment, including insecticides. The planthoppers Nilaparvata lugens and Sogatella furcifera are serious specialist pests of rice throughout eastern Asia. Their capacity to rapidly adapt to resistant rice varieties and to develop resistance to various insecticides has led to severe outbreaks over the last decade. Methodology/Principal Findings Using the genome sequence of N. lugens, we identified for the first time the complete GST gene family of a delphacid insect whilst nine GST gene orthologs were identified from the closely related species S. furcifera. Nilaparvata lugens has 11 GST genes belonging to six cytosolic subclasses and a microsomal class, many fewer than seen in other insects with known genomes. Sigma is the largest GST subclass, and the intron–exon pattern deviates significantly from that of other species. Higher GST gene expression in the N. lugens adult migratory form reflects the higher risk of this life stage in encountering the toxins of non-host plants. After exposure to a sub-lethal dose of four insecticides, chlorpyrifos, imidacloprid, buprofezin or beta-cypermethrin, more GST genes were upregulated in S. furcifera than in N. lugens. RNA interference targeting two N. lugens GST genes, NlGSTe1 and NlGSTm2, significantly increased the sensitivity of fourth instar nymphs to chlorpyrifos but not to beta-cypermethrin. Conclusions/Significance This study provides the first elucidation of the nature of the GST gene family in a delphacid species, offering new insights into the evolution of metabolic enzyme genes in insects. Further, the use of RNA interference to identify the GST genes induced by insecticides illustrates likely mechanisms for the tolerance of these insects.
Glutathione Transferase (GST)-Activated Prodrugs  [PDF]
Paolo Ruzza,Andrea Calderan
Pharmaceutics , 2013, DOI: 10.3390/pharmaceutics5020220
Abstract: Glutathione transferase (formerly GST) catalyzes the inactivation of various electrophile-producing anticancer agents via conjugation to the tripeptide glutathione. Moreover, several data link the overexpression of some GSTs, in particular GSTP1-1, to both natural and acquired resistance to various structurally unrelated anticancer drugs. Tumor overexpression of these proteins has provided a rationale for the search of GST inhibitors and GST activated cytotoxic prodrugs. In the present review we discuss the current structural and pharmacological knowledge of GST-activated cytotoxic compounds.
Cloning and Sequence Analysis of Glutathione Stransferase Gene in Delia antiqua  [PDF]
XIA Jie,CHEN Bin,HAO Youjin,SI Fengling
Journal of Chongqing Normal University , 2012,
Abstract: Glutathione Stransferase (GST) is a kind of detoxifying enzymes widely existing in insects. Its peroxidase vitality can protect the organisms against endogenous or oxide damage. The insect resistance to some pesticides is relative to the expression quantity of GST, and past research of insect GST mainly focused on the important role in the formation of pesticides resistance. This kind of genes can be used as the target of insecticide to design and develop new pesticides. In this research, the full length of GST cDNA of the onion maggot (Delia antiqua) was cloned using RACE technique (GenBank access number: JQ625502). The result showed that the full length of cDNA is 874 bp long, with an open reading frame (ORF) of 627 bp, encoding a protein of 208 amino acids with a calculated molecular weight of 239 kD and theoretical isolectric point of 583. The deduced amino acid sequence has the highest identity with that of Lucilia cuprina based homological analysis, and a phylogenic tree was inferred with homological GST sequences from other insects. The results provide a base and information frame for further research of the GST gene, and contribute to the related research of the insecticide resistance mechanism and development mechanism about Delia antiqua
A Glutathione Transferase from Agrobacterium tumefaciens Reveals a Novel Class of Bacterial GST Superfamily  [PDF]
Katholiki Skopelitou, Prathusha Dhavala, Anastassios C. Papageorgiou, Nikolaos E. Labrou
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0034263
Abstract: In the present work, we report a novel class of glutathione transferases (GSTs) originated from the pathogenic soil bacterium Agrobacterium tumefaciens C58, with structural and catalytic properties not observed previously in prokaryotic and eukaryotic GST isoenzymes. A GST-like sequence from A. tumefaciens C58 (Atu3701) with low similarity to other characterized GST family of enzymes was identified. Phylogenetic analysis showed that it belongs to a distinct GST class not previously described and restricted only in soil bacteria, called the Eta class (H). This enzyme (designated as AtuGSTH1-1) was cloned and expressed in E. coli and its structural and catalytic properties were investigated. Functional analysis showed that AtuGSTH1-1 exhibits significant transferase activity against the common substrates aryl halides, as well as very high peroxidase activity towards organic hydroperoxides. The crystal structure of AtuGSTH1-1 was determined at 1.4 ? resolution in complex with S-(p-nitrobenzyl)-glutathione (Nb-GSH). Although AtuGSTH1-1 adopts the canonical GST fold, sequence and structural characteristics distinct from previously characterized GSTs were identified. The absence of the classic catalytic essential residues (Tyr, Ser, Cys) distinguishes AtuGSTH1-1 from all other cytosolic GSTs of known structure and function. Site-directed mutagenesis showed that instead of the classic catalytic residues, an Arg residue (Arg34), an electron-sharing network, and a bridge of a network of water molecules may form the basis of the catalytic mechanism. Comparative sequence analysis, structural information, and site-directed mutagenesis in combination with kinetic analysis showed that Phe22, Ser25, and Arg187 are additional important residues for the enzyme's catalytic efficiency and specificity.
Glutathione S-transferase omega genes in Alzheimer and Parkinson disease risk, age-at-diagnosis and brain gene expression: an association study with mechanistic implications
Mariet Allen, Fanggeng Zou, High Chai, Curtis S Younkin, Richard Miles, Asha A Nair, Julia E Crook, V Pankratz, Minerva M Carrasquillo, Christopher N Rowley, Thuy Nguyen, Li Ma, Kimberly G Malphrus, Gina Bisceglio, Alexandra I Ortolaza, Ryan Palusak, Sumit Middha, Sooraj Maharjan, Constantin Georgescu, Debra Schultz, Fariborz Rakhshan, Christopher P Kolbert, Jin Jen, Sigrid B Sando, Jan O Aasly, Maria Barcikowska, Ryan J Uitti, Zbigniew K Wszolek, Owen A Ross, Ronald C Petersen, Neill R Graff-Radford, Dennis W Dickson, Steven G Younkin, Nilüfer Ertekin-Taner
Molecular Neurodegeneration , 2012, DOI: 10.1186/1750-1326-7-13
Abstract: We found that rs156697 minor allele associates with significantly increased risk (odds ratio = 1.14, p = 0.038) in the older ADs with age-at-diagnosis > 80 years. The minor allele of GSTO1 rs4925 associates with decreased risk in familial PD (odds ratio = 0.78, p = 0.034). There was no other association with disease risk or age-at-diagnosis. The minor alleles of both GSTO SNPs associate with lower brain levels of GSTO2 (p = 4.7 × 10-11-1.9 × 10-27), but not GSTO1. Pathway analysis of significant genes in our brain expression GWAS, identified significant enrichment for glutathione metabolism genes (p = 0.003).These results suggest that GSTO locus variants may lower brain GSTO2 levels and consequently confer AD risk in older age. Other glutathione metabolism genes should be assessed for their effects on AD and other chronic, neurologic diseases.Glutathione S-Transferase (GST) family of genes have been implicated in multiple neuropsychiatric [1-4] and neurodegenerative diseases [5-11]; where altered levels or function of these enzymes is thought to impact levels of oxidative stress and/or inflammation in a way that contributes to disease susceptibility. A linkage locus on chromosome 10q that has been implicated in both Alzheimer's (AD)[11-13] and Parkinson's disease (PD)[13] harbors two GST genes of the omega class: GSTO1 and GSTO2, which are approximately 75 kb apart.GSTOs have enzymatic activities as thioltransferases and dehydroascorbate reductases that promote antioxidant activity and can also function in metabolism of drugs and toxins[14]. Additionally, GSTO1 was shown to promote activation of the pro-inflammatory cytokine, interleukin-1β (IL-1β) by post-translational processing[15]. Given their location and function, they have been studied as candidate genes in AD and PD[5,6,9,11,14,16-18]. Li et al. compared hippocampal gene expression levels in 6 AD vs. 2 control brains and identified significantly lower GSTO1 levels in the AD hippocampi[5]. This group studied
Association of glutathione S-transferase (GSTM1, T1 and P1) gene polymorphisms with type 2 diabetes mellitus in north Indian population  [cached]
Bid H,Konwar R,Saxena M,Chaudhari P
Journal of Postgraduate Medicine , 2010,
Abstract: Background: Diabetes mellitus is associated with an increased production of reactive oxygen species (ROS) and a reduction in antioxidant defense. The oxidative stress becomes evident as a result of accumulation of ROS in conditions of inflammation and Type 2 diabetes mellitus (T2DM). The genes involved in redox balance, which determines the susceptibility to T2DM remain unclear. In humans, the glutathione S-transferase (GST) family comprises several classes of GST isozymes, the polymorphic variants of GSTM1, T1 and P1 genes result in decreased or loss of enzyme activity. Aims: The present study evaluated the effect of genetic polymorphisms of the GST gene family on the risk of developing T2DM in the North Indian population. Settings and Design: GSTM1, T1 and P1 polymorphisms were genotyped in 100 T2DM patients and 200 healthy controls from North India to analyze their association with T2DM susceptibility. Materials and Methods: Analysis of GSTM1 and GSTT1 gene polymorphisms was performed by multiplex polymerase chain reaction (PCR) and GSTP1 by PCR-Restriction Fragment Length Polymorphism (RFLP). Statistical Analysis: Fisher′s exact test and χ2 statistics using SPSS software (Version-15.0). Results: We observed significant association of GSTM1 null (P=0.004, OR= 2.042, 95%CI= 1.254-3.325) and GSTP1 (I/V) (P=0.001, OR= 0.397, 95%CI=0.225-0.701) with T2DM and no significant association with GSTT1 (P=0.493). The combined analysis of the three genotypes GSTM1 null, T1 present and P1 (I/I) demonstrated an increase in T2DM risk (P= 0.005, OR= 2.431 95% CI=1.315-4.496). Conclusions: This is the first study showing the association of a combined effect of GSTM1, T1 and P1 genotypes in a representative cohort of Indian patients with T2DM. Since significant association was seen in GSTM1 null and GSTP1 (I/V) and multiple association in GSTM1 null, T1 present and P1 (I/I), these polymorphisms can be screened in the population to determine the diabetic risk.
Glutathione S-Transferase of Brown Planthoppers (Nilaparvata lugens) Is Essential for Their Adaptation to Gramine-Containing Host Plants  [PDF]
Xiao-Qin Sun, Mao-Xin Zhang, Jing-Ya Yu, Yu Jin, Bing Ling, Jin-Ping Du, Gui-Hua Li, Qing-Ming Qin, Qing-Nian Cai
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0064026
Abstract: Plants have evolved complex processes to ward off attacks by insects. In parallel, insects have evolved mechanisms to thwart these plant defenses. To gain insight into mechanisms that mediate this arms race between plants and herbivorous insects, we investigated the interactions between gramine, a toxin synthesized by plants of the family Gramineae, and glutathione S transferase (GST), an enzyme found in insects that is known to detoxify xenobiotics. Here, we demonstrate that rice (Oryza sativa), a hydrophytic plant, also produces gramine and that rice resistance to brown planthoppers (Nilaparvata lugens, BPHs) is highly associated with in planta gramine content. We also show that gramine is a toxicant that causes BPH mortality in vivo and that knockdown of BPH GST gene nlgst1-1 results in increased sensitivity to diets containing gramine. These results suggest that the knockdown of key detoxification genes in sap-sucking insects may provide an avenue for increasing their sensitivity to natural plant-associated defense mechanisms.
GST genotypes in head and neck cancer patients and its clinical implications
K Sabitha, MVV Reddy, K Jamil
African Journal of Biotechnology , 2008,
Abstract: Polymorphisms of carcinogen-metabolizing enzymes, known to be involved in metabolism of carcinogens found in tobacco smoke, are relatively common in most populations. Cigarette and bidi smoking has been demonstrated to increase the risk of head and neck cancers in our study group. This study evaluated the risk of head and neck cancers (HNC) in relation to two deletion polymorphisms of the glutathione S-transferase family GST M1 and GST T1. We found that the null GST M1 and GST T1 genotypes were associated with an increased risk of developing head and neck cancers. We found smokers, with null genotypes of GST M1 (68.3%) and GST T1 (57.5%) were at a significantly higher risk of head and neck cancers. It is possible that the decreased activity of GST affects various functions like the mechanisms of DNA damage, including those mediated by tobacco and oxidative stress. The present study investigated whether homozygous gene deletions of GST M1 and GST T1 increases the incidence of head and neck cancers and explored the relationship between the GST genotype patients to clarify the multistep pathogenesis of these cancers based on this possible genetic predisposition. Based on these results it is also concluded that genotyping of GSTs would be a useful biomarker for determining the risk of head and neck cancers in bidi and cigarette smokers.
Purification of glutathione-S-transferase fusion protein by glutathione coupled magnetic particles

Jingjing Zhu,Liu Yang,Lei Yang,Chao Chen,Yali Cui,

生物工程学报 , 2009,
Abstract: We established a purification system for glutathione-S-transferase(GST) fusion protein using glutathione coupled magnetic particle.Glutathione was coupled covalently to the surface of magnetic particles with isothiocyanate functional groups.Cell lysate,containing the fusion protein,was then incubated with these glutathione coupled magnetic particles at room temperature.Unbound and non-specifically bound proteins were removed by wash steps.Subsequently,the GST-fusion protein was eluted from the magnetic part...
Comparative Genomics of the Anopheline Glutathione S-Transferase Epsilon Cluster  [PDF]
Constancia Ayres, Pie Müller, Naomi Dyer, Craig Wilding, Daniel Rigden, Martin Donnelly
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0029237
Abstract: Enzymes of the glutathione S-transferase (GST) family play critical roles in detoxification of xenobiotics across many taxa. While GSTs are ubiquitous both in animals and plants, the GST epsilon class (GSTE) is insect-specific and has been associated with resistance to chemical insecticides. While both Aedes aegypti and Anopheles gambiae GSTE clusters consist of eight members, only four putative orthologs are identifiable between the species, suggesting independent expansions of the class in each lineage. We used a primer walking approach, sequencing almost the entire cluster from three Anopheles species (An. stephensi, An. funestus (both Cellia subgenus) and An. plumbeus (Anopheles subgenus)) and compared the sequences to putative orthologs in An. gambiae (Cellia) in an attempt to trace the evolution of the cluster within the subfamily Anophelinae. Furthermore, we measured transcript levels from the identified GSTE loci by real time reverse transcription PCR to determine if all genes were similarly transcribed at different life stages. Among the species investigated, gene order and orientation were similar with three exceptions: (i) GSTE1 was absent in An. plumbeus; (ii) GSTE2 is duplicated in An. plumbeus and (iii) an additional transcriptionally active pseudogene (ψAsGSTE2) was found in An. stephensi. Further statistical analysis and protein modelling gave evidence for positive selection on codons of the catalytic site in GSTE5 albeit its origin seems to predate the introduction of chemical insecticides. Gene expression profiles revealed differences in expression pattern among genes at different life stages. With the exception of GSTE1, ψAsGSTE2 and GSTE2b, all Anopheles species studied share orthologs and hence we assume that GSTE expansion generally predates radiation into subgenera, though the presence of GSTE1 may also suggest a recent duplication event in the Old World Cellia subgenus, instead of a secondary loss. The modifications of the catalytic site within GSTE5 may represent adaptations to new habitats.
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