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Glutathione S-transferase widely exist in vivo, play a major role in the metabolic processes in the detoxification of chemical pesticides. The migratory locust is one of the major agricultural pests, greater harm to our country's agricultural production. In recent years, along with climate change and the destruction of the ecological environment, locust infestation growing, and with the abuse of chemical pesticides cause locusts reduced susceptibility to insecticides. In order to more efficiently deal with the locusts of locusts has material systems research at the molecular and protein levels of glutathione S-transferase. The main content is as follows: First, the transfer of the migratory locust glutathione S Gene Cloning the 10 the migratory locust GSTs sequence fragments from the migratory locust EST database, confirmed by BLASTX than with the NCBI database, obtained by RACE-PCR technique 10 migratory locust Glutathione S-transferase full-length cDNA sequences. After the amino acid sequence comparison and system evolution clustering analysis of the 9 cytoplasmic GSTs belonging to the three families of GSTs, which the one belonging delta family (LmGSTd1), 7 were sigma family (LmGSTs1, LmGSTs2, LmGSTs3, LmGSTs4, LmGSTs5, LmGSTs6, and LmGSTs7 ), a belonging the the theta family (LmGSt1). The remaining one GST with known family insects GSTs have lower correlation normalized for the unclassified family (LmGSTu1). Second, the migratory locust glutathione S transferase gene molecular characteristics of the RT-PCR method, the detection of glutathione S-transferase genes in the migratory locust eggs, 1 expression at different developmental stages to adult age. Found that lower LmGSTs1, LmGSTs4, LmGSTs6 and LmGSTs1 four gene expression levels of mRNA in the egg stage, LmGSTu1 no expression in the egg stage. The LmGSTd1, LmGSTs1, LmGSTs3, LmGSTs5 and LmGSTt1 expressed in various developmental stages of the migratory locust did not change significantly. By RT-PCR method for detection of glutathione S-transferase gene expression in locusts foregut, midgut caecum, hindgut, Malpighian tubules, fat body, muscle, testes and ovaries nine different tissues situation. The results found LmGSTd1, LmGSTs1 LmGSTs3, LmGSTs5 LmGSTs6 LmGSTt1 6 gene in all tissues expression. LmGSTs2, LmGSTs4, LmGSTs1 and LmGSTu1 expression in some tissues. Real-time PCR findings the deltamethrin concentration 0.08μg/mL with 0.12μg/mL migratory locust 3rd instar nymphs 10 Glutathione S-transferase gene mRNA expression increased. However, when the deltamethrin concentration, LmGSTs1, LmGSTs5 and LmGSTs6 the mRNA expression levels in 0.16μg/mL or 0.2μg/mL when LmGSTd1 reduce the The deltamethrin treated the migratory locust glutathione S-transferase enzyme mRNA expression increased, may cause locusts has increased tolerance of other pesticides and xenobiotics. The three migratory locust glutathione S-transferase the the zymogen nuclear expression and protein characteristics the study successfully expressed in E. coli and purified to obtain the soluble protein LmGSTt 1 and LmGSTsl. LmGSTt1 and LmGSTs1 can two substrates react with the CDNB (1-chloro-2 ,4-dinitrobenzene) and p-NBC (p-nitro-benzyl chloride), wherein CDNB is the optimal substrate. The in the 40 ℃ LmGSTt1 and LmGSTs1 have better stability. In the GST inhibitors ECA (ethacrynic acid) and RB (reactive blue) concentration of 0.05mM LmGSTt1 of activity were reduced to 37 ± 1% and ± 0.1%. The 150 value ECA on LmGSTt1 12.6μM. RB 150 value LmGSTtl 4.41μM; LmGSTs1 activity decreased to 81 ± 3% and 41 ± 3%, respectively. The 150 value RB on LmGSTs1 18.5μM. Chlorpyrifos, deltamethrin, malathion and carbaryl insecticide concentration 0.05mM when LmGSTt1 activity were reduced to 71 ± 3%, 88 ± 2%, 94 ± 2% and 83 ± 1% , while there was no significant effect LmGSTs1 on the above pesticides.
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