Studies of the small RNA specificity and the viral pathogenicity in plants

2016 Fiscal Year Final Research Report

• Project/Area Number: 15K14665
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant protection science
• Research Institution: Ritsumeikan University
• Principal Investigator: Takeda Atsushi 立命館大学, 生命科学部, 准教授 (60560779)
• Co-Investigator(Renkei-kenkyūsha): SATO MASANAO 北海道大学, 農学研究院, 助教 (20517693)
• Project Period (FY): 2015-04-01 – 2017-03-31
• Keywords: ウイルス由来siRNA / RNAサイレンシング / AGO1 / Nicotiana benthamiana / miRNA

Outline of Final Research Achievements

In plants, viral infection induces RNA silencing, which is a basal immune response against viruses. In the anti-viral pathways of plant RNA silencing, abundant viral-derived small-interfering RNAs (vsiRNAs) are generated through functions of Dicer-like enzymes (DCLs). A class of 21 nt vsiRNAs cleaved by DCL4 is incorporated into Argonaute 1 (AGO1). The AGO1-vsiRNA complex has a potential to cleave not only viral RNAs but also endogenous mRNAs dependent on the complementarity between target RNAs and vsiRNAs in AGO1. However, determinants of target specificity of AGO1-vsiRNA complex are unknown and thus we cannot predict the target mRNAs downregulated upon viral infection. In this study, we examined the AGO1 specificity in plants experimentally by using a massive transient luciferase assay. We identified several determinants of the plant AGO1 specificity, which can help predict the target mRNAs of vsiRNAs in viral-infected plants in future.

Free Research Field

植物ウイルス学