title: Impacts on silkworm larvae midgut proteomics by transgenic Trichoderma strain and analysis of glutathione S-transferase sigma 2 gene essential for anti-stress response of silkworm larvae.
abstract: Lepidoptera is a large order of insects that have major impacts on humans as agriculture pests. The midgut is considered an important target for insect control. In the present study, 10 up-regulated, 18 down-regulated, and one newly emerged protein were identified in the transgenic Trichoderma-treated midgut proteome. Proteins related to stress response, biosynthetic process, and metabolism process were further characterized through quantitative real-time PCR (qPCR). Of all the identified proteins, the glutathione S-transferase sigma 2 (GSTs2) gene displayed enhanced expression when larvae were fed with Trichoderma wild-type or transgenic strains. Down regulation of GSTs2 expression by RNA interference (RNAi) resulted in inhibition of silkworm growth when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. Weight per larva decreased by 18.2%, 11.9%, and 10.7% in the untreated control, ddH2O, and GFP dsRNA groups, respectively, at 24h, while the weight decrease was higher at 42.4%, 28.8% and 32.4% at 72 h after treatment. Expression of glutathione S-transferase omega 2 (GSTo2) was also enhanced when larvae were fed with mulberry leaves treated with the transgenic Trichoderma strain. These results indicated that there was indeed correlation between enhanced expression of GSTs2 and the anti-stress response of silkworm larvae against Trichoderma. This study represents the first attempt at understanding the effects of transgenic organisms on the midgut proteomic changes in silkworm larvae. Our findings could not only broaden the biological control targets of insect at the molecular level, but also provide a theoretical foundation for biological safety evaluation of the transgenic Trichoderma strain.
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China; College of Life Science, Liaoning Normal University, Dalian, China.
authors.forename: Yingying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Kai
authors.initials: K
authors.lastname: Dou
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Shigang
authors.initials: S
authors.lastname: Gao
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Jianan
authors.initials: J
authors.lastname: Sun
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Kehe
authors.initials: K
authors.lastname: Fu
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Chuanjin
authors.initials: C
authors.lastname: Yu
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Wu
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China.
authors.forename: Yaqian
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Resource and Environmental Science, School of Agriculture and Biology, Shanghai Jiaotong University, Shanghai 200240, China. Electronic address: jiechen59@sjtu.edu.cn.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
mesh_terms: D000818:Animals; D012831:Bombyx / Q000201:enzymology / Q000382:microbiology; D015971:Gene Expression Regulation, Enzymologic; D005982:Glutathione Transferase / Q000096:biosynthesis*; D019476:Insect Proteins / Q000096:biosynthesis*; D007422:Intestines / Q000201:enzymology / Q000382:microbiology; D007814:Larva / Q000201:enzymology / Q000382:microbiology; D014242:Trichoderma / Q000235:genetics / Q000254:growth & development*
chemical_list: D019476:Insect Proteins; D005982:Glutathione Transferase
keywords: GSTs2; Midgut proteome; RNAi; Silkworm; Trichoderma