Molecular analyses of RNA silencing amplification system in plants

2015 Fiscal Year Final Research Report

• Project/Area Number: 24248010
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Plant pathology
• Research Institution: National Institute of Agrobiological Sciences
• Principal Investigator: Tesuo Meshi 国立研究開発法人農業生物資源研究所, その他部局等, その他 (40157813)
• Co-Investigator(Kenkyū-buntansha): ISHIKAWA Masayuki 農業生物資源研究所, 植物科学研究領域・植物-微生物間相互作用研究ユニット, ユニット長 (70192482) ; YOSHIKAWA Manabu 農業生物資源研究所, 植物科学研究領域・植物-微生物間相互作用研究ユニット, 主任研究員 (80391564) ; ISHIBASHI Kazuhiro 農業生物資源研究所, 植物科学研究領域・植物-微生物間相互作用研究ユニット, 主任研究員 (20611742)
• Project Period (FY): 2012-04-01 – 2016-03-31
• Keywords: RISC複合体 / trans-acting siRNA / microRNA / リボソーム / ウイルス / サプレッサー

Outline of Final Research Achievements

Plants have an RNA silencing amplification system, in which secondary small interfering RNAs (siRNAs) are produced from RISC-cleaved RNAs. This system plays a crucial role in virus resistance. To elucidate the molecular mechanisms of RNA silencing amplification, we analyzed Arabidopsis microRNA173-triggered trans-acting siRNA production using an in vitro RISC formation system. We discovered that SGS3 forms a complex that contains AGO1 and cleaved RNAs, and stabilizes RISC-cleaved RNAs. We also found that ribosomes associate with TAS2 RNA that had been thought to be non-coding. Further, we showed that a short open reading frame (ORF) that encompasses the microRNA173 target site on TAS2 RNA positively regulates production of tasiRNAs.

Free Research Field

植物保護学