Explorations of metabolic factors involved in efficient cellulolytic systems in insects

2016 Fiscal Year Final Research Report

• Project/Area Number: 26292177
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Insect science
• Research Institution: University of the Ryukyus
• Principal Investigator: TOKUDA Gaku 琉球大学, 熱帯生物圏研究センター, 教授 (90322750)
• Co-Investigator(Kenkyū-buntansha): 菊地 淳 国立研究開発法人理化学研究所, 環境資源科学研究センター, チームリーダー (00321753) ; 大熊 盛也 国立研究開発法人理化学研究所, バイオリソースセンター, 室長 (10270597)
• Research Collaborator: HONGOH Yuichi ; KINJO Yukihiro ; KUMARA Rohitha P. ; NALEPA Christine A. ; PARK Yung Chul
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 昆虫生理生化学 / セルロース代謝 / 栄養共生 / セルラーゼ / シロアリ / ゴキブリ / 消化系進化 / 輸送分子

Outline of Final Research Achievements

The present study explored metabolic factors that involved in invention of efficient cellulolytic systems during evolution from wood roaches to termites. In evolution of wood roaches to lower termites, we found some overlaps of metabolic networks between endo- and intestinal symbioses, which had led to relaxed selection of some genes in endosymbionts and increased in dependence of the host insects in intestinal symbionts. In lower termites, we analyzed a genome sequence of a Japanese subterranean lower termite. Endogenous cellulase genes were duplicated in the genome, while a few of them appeared to differentiate their functions. Furthermore, we analyzed transcripts of the so-called “the mixed segment” in the gut of a higher termite, which expressed a variety of transporter genes. Among them, V-ATPases and NHE transporters were assumed to be involved in the gut alkalization, which may contribute to solubilize lignin to facilitate cellulose degradation by the intestinal bacteria.

Free Research Field

昆虫生理学