Identification of glutathione-S-transferase genes by transcriptome analysis in Meteorus pulchricornis (Hymenoptera: Braconidae) and their expression patterns under stress of phoxim and cypermethrin

Meteorus pulchricornis (Wesmael) (Hymenoptera: Braconidae) is a preponderant endoparasitoid wasp, attacking the larvae of many lepidopteran pests. We present the first body transcriptome dataset for M. pulchricornis . In total, 50,781,796 clean reads were obtained and 33,144 unigenes were assembled; 15,458 unigenes showed a significant similarity (E value < 10 −5 ) to known proteins in the NCBI non-redundant protein database . Gene ontology and cluster of orthologous group analyses were performed to classify the functions of genes. To better understand the role of glutathione-S-transferases (GSTs) in detoxification mechanism in M. pulchricornis , we identified seventeen GST genes ( MpulGSTs ) from the body transcriptome. Among these, fifteen MpulGSTs belonged to cytosolic GSTs and the other two belonged to microsomal classes. The cytosolic GSTs were classified into four different clades: four in delta, three in omega, seven in sigma, and one in zeta. The expression levels of these MpulGSTs after exposure to sub-lethal concentrations of phoxim and cypermethrin were determined using real-time quantitative polymerase chain reaction: seven MpulGSTs ( MpulGSTD3 , MpulGSTS1 , MpulGSTS2 , MpulGSTS4 , MpulGSTS6 MpulGSTO3 , and MpulGSTmic1 ) and 11 MpulGSTs ( MpulGSTD1 , MpulGSTD2 , MpulGSTD3 , MpulGSTO2 , MpulGSTS1 , MpulGSTS2 , MpulGSTS3 , MpulGSTS4 , MpulGSTS5 , MpulGSTS7 , and MpulGSTmic1 ) were highly expressed, respectively. These results suggested that GST genes may play a pivotal role in detoxification process in M. pulchricornis . Our findings would provide a theoretical base for elucidating insecticide susceptibility and should promote functional research on specific GST genes in parasitoid wasps.