Molecular mechanism intervened between the action of diapause hormone on developing ovaries and the expression of pnd gene that is the diapause-initiating gene

2015 Fiscal Year Final Research Report

• Project/Area Number: 24380033
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Applied entomology
• Research Institution: Nagoya University
• Principal Investigator: YAGINUMA Toshinobu 名古屋大学, 生命農学研究科, 名誉教授 (60135332)
• Co-Investigator(Kenkyū-buntansha): NIIMI Teruyuki 基礎生物学研究所, 大学共同利用機関等の部局等, 教授 (00293712)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: 昆虫分子生物学 / 蚕糸学 / カイコ胚休眠 / 休眠ホルモン / 休眠開始遺伝子 / 遺伝子発現調節 / シグナル伝達系

Outline of Final Research Achievements

In the silkworm (Bombyx mori), diapause hormone that is biosynthesized in the subesophageal ganglion is released into the hemolymph and acts on developing ovaries in the mid-pupal stage of females, in order to induce embryonic diapause that occurs 2-3 days after oviposition. As a diapause-initiating gene, we have already isolated the pnd (pigmented and nondiapausing egg) gene. Therefore, we here conducted the experiments to examine whether the insulin-signal transduction system is intervened between the diapause-signal and the expression of pnd gene. We show that the mRNA expression of insulin-like peptide (BmILP) is lowered in diapause-eggs than in nondiapause-eggs, and that the cis-element recognized and bound by FoxO transcriptional factor located at the downstream of insulin-signal transduction system is found in the 5’-upstream region of the pnd gene.

Free Research Field

昆虫科学