Study of suppression mechanisms of anti-viral PTGS of host plant in Cucumber mosaic virus infection

Research Project

Project/Area Number	24580069
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Plant pathology
Research Institution	Osaka Prefecture University
Principal Investigator	OHKI Satoshi T. 大阪府立大学, 生命環境科学研究科(系), 教授 (00128761)
Co-Investigator(Renkei-kenkyūsha)	MOCHIZUKI Tomofumi 大阪府立大学, 生命環境科学研究科, 助教 (30469837)
Project Period (FY)	2012-04-01 – 2015-03-31
Project Status	Completed (Fiscal Year 2014)
Budget Amount *help	¥5,590,000 (Direct Cost: ¥4,300,000、Indirect Cost: ¥1,290,000) Fiscal Year 2014: ¥780,000 (Direct Cost: ¥600,000、Indirect Cost: ¥180,000) Fiscal Year 2013: ¥1,040,000 (Direct Cost: ¥800,000、Indirect Cost: ¥240,000) Fiscal Year 2012: ¥3,770,000 (Direct Cost: ¥2,900,000、Indirect Cost: ¥870,000)
Keywords	キュウリモザイクウイルス / ウイルスサプレッサー / PTGS / VIGS / タバコ / シロイヌナズナ
Outline of Final Research Achievements	Effects of Cucumber mosaic virus (CMV) pepo strain infection on post-transcriptional gene silencing (PTGS) in host plants were investigated. To distinguish the primary and the secondary PTGS, we prepared transgenic tobacco carrying GFP mRNA and GF (5′ two-third region of GFP gene) inverted-repeat constructs; siRNA from P region (3’ one-third region of GFP gene) that was indicator of secondary PTGS was not detected, suggesting that the secondary PTGS was not induced toward 3′ region of the GFP mRNA. We also constructed mutated CMV that had the 30 nt GFP sequence. Inoculation of the mutated CMV to the GFP expressing transgenic tobacco showed virus-induced gene silencing (VIGS) of GFP. Secondary VIGS in the 5′ region of GFP was observed but not in the 3′ region. Finally, we examined the effect of CMV pepo infection on endogenous PTGS, such as miRNA and ta-siRNA, of Arabidopsis. CMV pepo infection increased the expression of mRNAs that were targets of miRNA or ta-siRNA.