Analysis of the regulation of BmAgo3 phosphorylation

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06484
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 43010:Molecular biology-related
• Research Institution: The University of Tokyo
• Principal Investigator: Natsuko Izumi 東京大学, 定量生命科学研究所, 技術専門職員 (50579274)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: piRNA / Siwi / BmAgo3 / Gtsf

Outline of Final Research Achievements

In this study, we initially planned to analyze the regulation of BmAgo3 phosphorylation, but after the study was initiated, another group reported related results. Because of this, we changed the research topic and analyzed the BmAgo3 complex in the absence of Siwi, where the phosphorylation of BmAgo3 is enhanced. In this analysis, we found that Gtsf1L, a paralog of Gtsf1, one of evolutionarily conserved piRNA factors, accumulates in the BmAgo3 complex in the absence of Siwi. We obtained results suggesting that silkworm two Gtsf paralogs, Gtsf1 and Gtsf1L, independently function in the piRNA pathway by specifically interacting with Siwi and BmAgo3 respectively and promoting their target cleavage.

Free Research Field

RNAサイレンシング

Academic Significance and Societal Importance of the Research Achievements

piRNAが産生できない動物個体は、配偶子形成が不全となり不妊となる。ヒトの無精子症においても、piRNA産生に関わる因子の変異が報告されてきており、piRNA産生の分子機構の解明は、不妊症の原因理解にもつながる社会的意義のある研究課題である。PIWIの標的切断はpiRNA産生の原動力となっていることから、本研究を契機に明らかとなった、カイコGtsfタンパク質によるPIWIの標的切断の促進は、piRNA産生機構の理解を大きく前進させるものといえる。