Integrated regulatory system by functional sRNA and mRNA-binding protein CsrA

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K07004
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 49050:Bacteriology-related
• Research Institution: Ehime Prefectural University of Health Science
• Principal Investigator: Mima Takehiko 愛媛県立医療技術大学, 保健科学部, 教授 (80596437)
• Co-Investigator(Kenkyū-buntansha): 港 雄介 藤田医科大学, 医学部, 講師 (10836620)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 発現調節 / sRNA / RNA binding protein / Vibrio

Outline of Final Research Achievements

VarS/VarA two-component regulatory system controls the expression of target genes through regulating the transcription of small RNAs (sRNAs). Bacteria possesses several copies of sRNA genes which were thought to be redundant. Vibrio alginolyticus possesses four copies of sRNAs. We have found the possibility that different proteins regulate the expression of their respective sRNAs. This study revealed that the expression of one of the four sRNAs, sRNA1, is regulated by the anaerobic state signal via ArcB/ArcA two-component regulatory system and leucine signals via Lrp. Based on these results, we proposed a model in which the regulatory system consisting of the multiple copies of sRNAs and an mRNA-binding protein CsrA is an integrated regulatory system that integrates multiple environmental signals to optimize the expression of target genes.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

本研究は、これまでVarS/VarA二成分制御系の構成因子とされていた複数コピーのsRNAが、他の複数の環境シグナルによっても別々に制御されることを初めて示した。その結果から、それら複数コピーのsRNAとRNA結合タンパク質CsrAからなる制御系が、複数の環境シグナルを統合して演算し、環境の変化に適応するための複数の標的遺伝子の発現を統合的に調節する(multiple-input and multiple-output)という全く新しい発現調節機構（sRNAs-CsrA統合制御システム）であると考えられることを示した学術的意義の大変高いものである。