title: Activation of the TOR Signalling Pathway by Glutamine Regulates Insect Fecundity.
abstract: The target of rapamycin (TOR) positively controls cell growth in response to nutrients such as amino acids. However, research on the specific nutrients sensed by TOR is limited. Glutamine (Gln), a particularly important amino acid involved in metabolism in organisms, is synthesised and catalysed exclusively by glutamine synthetase (GS), and our previous studies have shown that Gln may regulate fecundity in vivo levels of the brown planthopper (BPH) Nilaparvata lugens. Until now, it has remained unclear whether Gln activates or inhibits the TOR signalling pathway. Here, we performed the combined analyses of iTRAQ (isobaric tags for relative and absolute quantification) and DGE (tag-based digital gene expression) data in N. lugens at the protein and transcript levels after GS RNAi, and we found that 52 pathways overlap, including the TOR pathway. We further experimentally demonstrate that Gln activates the TOR pathway by promoting the serine/threonine protein kinase AKT and inhibiting the 5'AMP-activated protein kinase AMPK phosphorylation activity in the pest. Furthermore, TOR regulates the fecundity of N. lugens probably by mediating vitellogenin (Vg) expression. This work is the first report that Gln activates the TOR pathway in vivo.
authors.affiliation: 1] State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China [2] Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
authors.forename: Yifan
authors.initials: Y
authors.lastname: Zhai
authors.affiliation: State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Zhongxiang
authors.initials: Z
authors.lastname: Sun
authors.affiliation: State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jianqing
authors.initials: J
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Kui
authors.initials: K
authors.lastname: Kang
authors.affiliation: State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Wenqing
authors.initials: W
authors.lastname: Zhang
mesh_terms: D055372:AMP-Activated Protein Kinases / Q000378:metabolism; D000818:Animals; D004789:Enzyme Activation; D005298:Fertility; D005786:Gene Expression Regulation; D055785:Gene Knockdown Techniques; D005974:Glutamate-Ammonia Ligase / Q000235:genetics; D005973:Glutamine / Q000378:metabolism*; D007313:Insecta; D008954:Models, Biological; D020543:Proteome; D051057:Proto-Oncogene Proteins c-akt / Q000378:metabolism; D034622:RNA Interference; D015398:Signal Transduction; D058570:TOR Serine-Threonine Kinases / Q000378:metabolism*
chemical_list: D020543:Proteome; D005973:Glutamine; D051057:Proto-Oncogene Proteins c-akt; D058570:TOR Serine-Threonine Kinases; D055372:AMP-Activated Protein Kinases; D005974:Glutamate-Ammonia Ligase