Analysis on the molecular function of a cohesin-like protein in homologous recombination repair

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K07202
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Genome biology
• Research Institution: Gakushuin University
• Principal Investigator: Keyamura Kenji 学習院大学, 理学部, 助教 (70464386)
• Research Collaborator: HISHIDA takashi
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: DNA切断修復 / 相同組換え / SMCファミリー

Outline of Final Research Achievements

DNA double-strand breaks (DSBs) are a major threat to genome stability and cell survival, and if left unrepaired or repaired inappropriately, can lead to genomic mutations or cell death. Homologous recombination (HR) is highly conserved in all organisms and plays a critical role in DSB repair. SMC (structural maintenance of chromosomes) family proteins, including cohesin and the SMC5-6 complex in eukaryotes, play a crucial role in HR, however those molecular mechanisms remain unknown. In this research subject, An Escherichia coli RecN protein, which is the SMC family and related to HR repair of DSBs, was analyzed using a biochemical technique for understanding its molecular function. As a result, this study demonstrates that RecN has a cohesin-like activity that links between DNA molecules and promotes an initial process in HR.

Free Research Field

DNA修復、生化学、分子生物学

Academic Significance and Societal Importance of the Research Achievements

大腸菌のRecNは、ゲノムDNA切断時の相同組換え修復に関わるRecファミリーの中で、唯一機能が未解明であったタンパク質である。本研究課題において、代表者は、RecNタンパク質を精製、解析することによって、その分子機能を明らかにした。真核生物のSMCファミリータンパク質の中には相同組換え修復に関わるものが報告されているものの、その分子メカニズムは不明である。そのため、本研究成果は、大腸菌の相同組換え修復の分子機構の解明に貢献するだけでなく、真核生物の相同組換え修復に関与するSMCタンパク質の分子機能の基盤を築くことができ、がん化や遺伝子疾患などの発生機構の理解につながることが期待できる。