Structural basis for DNA repair machinery including RNA/DNA heteroduplex

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K23733
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0701:Biology at molecular to cellular levels, and related fields
• Research Institution: Aichi Cancer Center Research Institute (2020); Ritsumeikan University (2019)
• Principal Investigator: Uehara Ryo 愛知県がんセンター(研究所), 腫瘍制御学分野, 研究員 (70842590)
• Project Period (FY): 2019-08-30 – 2021-03-31
• Keywords: RNase H2 / DNA修復 / BRCA2 / RNA/DNAハイブリッド / X線結晶構造解析

Outline of Final Research Achievements

In this study, we biochemically analyzed the complex between RNase H2 and BRCA2 repeat peptides to reveal how RNase H2 is recruited to the site of DNA double strand breaks where an RNA/DNA heteroduplex is formed. For a comparative study, we purified and crystallized a recombinant protein of RNase H2 from E. coli (Ec-RNase H2), which exhibits the distinct RNA/DNA hydrolysis activity from that of the human enzyme. Furthermore, we generated the synthetic binding proteins that may act as a crystallization chaperone for Ec-RNase H2.

Free Research Field

分子生物学

Academic Significance and Societal Importance of the Research Achievements

RNase H2とBRCA2リピートペプチドの組み換えタンパク質を用いた相互作用解析によって、二者間の結合は極めて弱く、RNase H2がDNA損傷部位へ誘導されるためには他のタンパク質が関与する可能性が示唆された。RNase H2の遺伝子への変異は先天性自己免疫疾患やがんと深く関与しており、その生理機能について詳細な分子機構の解明は、疾患発症メカニズムの理解や新規治療標的の発見という点において意義深い。