Elucidation of the mechanism of selective accumulation of amino acids; identification of elicitor from the rice root aphid.

• Project/Area Number: 16K15069
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Insect science
• Research Institution: Kochi University
• Principal Investigator: Tebayashi Shinichi 高知大学, 教育研究部自然科学系農学部門, 准教授 (70325405)
• Research Collaborator: Oonishi Shintaro ; Yamashita Saki ; Sumida Hayato ; Yamada Chika ; Maseda Hideaki
• Project Period (FY): 2016-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2018: ¥650,000 (Direct Cost: ¥500,000、Indirect Cost: ¥150,000); Fiscal Year 2017: ¥1,430,000 (Direct Cost: ¥1,100,000、Indirect Cost: ¥330,000); Fiscal Year 2016: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: rice / aphid / イネ / エリシター / アミノ酸 / アブラムシ

Outline of Final Research Achievements

The rice root aphid, Rhopalosiphum rufiabdominalis, can induce a mechanism to accumulate amino acids and serotonin in a rice root and utilizes these nourishments for their growth and reproduction. Isopentenyladenine was identified as an elicitor from the rice root aphid itself. An exogenous isopentenyladenine treatment to a root could induce an accumulation of serotonin, and then it was concluded that isopentenyladenine could act as a trigger of the mechanism to modify a nutritional condition in a rice root.

Academic Significance and Societal Importance of the Research Achievements

昆虫-植物相互作用の契機となるエリシターの研究はその困難さから数が少なく、現在まで数種の化合物が報告されているにすぎない。特に寄主昆虫が有利に働く因子の報告例は今回が初めてであり、学術的にも意義深い。また、近年、昆虫にサイトカイニンであるイソペンテニルアデニンとゼアチンが散発的に存在することが報告されているものの、その存在意義は不明なままであった。今回の研究では昆虫が寄主植物の栄養状態を改善するために植物ホルモン自体を利用している可能性が示され、これが普遍的な現象であれば昆虫-植物の相互作用のメカニズムに新たな常識を確立するものとなり、植物生理・昆虫生理の両分野のマイルストーンとなる。

Research Products

• [Journal Article] Accumulation of 9- and 13-KODEs in response to jasmonic acid treatment and pathogenic infection in rice, (2018)
  • Author(s): Nishiguchi, S, Murata, K, Ube, N, Ueno, K, Tebayashi, S, Teraishi, M, Okumoto, Y, Mori, N, Ishihara,
  • Journal Title: Journal of Pesticide Science Volume: 81 Pages: 191-197
  • NAID: 130007437390
• [Journal Article] Distribution of the tryptophan-pathway-derived defensive secondary metabolites gramine and benzoxazinones in Poaceae. (2017)
  • Author(s): Kokubo Y, Nishizaka M, Ube N, Yabuta Y Tebayashi SI, Ueno K, Taketa S, Ishihara A
  • Journal Title: Biosci Biotechnol Biochem. Volume: 81 Issue: 3 Pages: 431-440
  • DOI: 10.1080/09168451.2016.1256758
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Presentation] Induced resistance on the root of rice plant by plant hormones against root aphid. (2018)
  • Author(s): Shinichi Tebayashi*1, Hayato Sumita1, Akira OIKAWA2, Hideaki MASEDA3, Atsushi ISHIHARA4
  • Organizer: ISCE 34th Annual Meeting, Budapest, Hungary,
  • Int'l Joint Research
• [Presentation] オカボノアカアブラムシのイネ根への寄生によるアミノ酸の蓄積 (2017)
  • Author(s): ， 佐々木 亮介， 斉藤 和季， 上手 麻希， 間世田 英明， 石原 亨
  • Organizer: 日本農芸化学会2016年度大会
  • Place of Presentation: 京都
  • Year and Date: 2017-03-17
• [Remarks] 高知大学農林海洋科学部化学生態学研究室HP
  • URL: http://www.cc.kochi-u.ac.jp/~tebayasi/index.html