Posttranscriptional regulation and mutual regulation of small RNA

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K08830
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Bacteriology (including mycology)
• Research Institution: Okayama University
• Principal Investigator: Mima Takehiko 岡山大学, 医歯薬学総合研究科, 助教 (80596437)
• Co-Investigator(Kenkyū-buntansha): 後藤 和義 岡山大学, 医歯薬学総合研究科, 助教 (20626593)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 二成分制御系 / small RNA / sRNA / 発現調節 / 環境シグナル

Outline of Final Research Achievements

VarS/VarA two-component system controls the expression of target genes thorough regulating the expression of small RNAs (sRNAs). In other bacteria, the expression of sRNAs is considered to be regulated only by VarS/VarA system. Vibrio alginolyticus has four sRNAs. In this study, we found that different proteins bound to the promoter region of each sRNA. We also revealed that ArcA, a response regulator of ArcB/ArcA two-component regulatory system, bound only to the promoter region of sRNA1, but not to those of other sRNAs. Furthermore, we revealed that ArcB/ArcA system regulates the expression of sRNA1 when cells were grown under anaerobic conditions. It seems likely that expression of VarS/VarA-controlled sRNAs were controlled not only by VarS/VarA, but also by multiple regulators. From these results, we propose that sRNAs is the arithmetic system to optimize the expression of many target genes by integrating multiple environmental signals.

Free Research Field

細菌学

Academic Significance and Societal Importance of the Research Achievements

本研究成果は、これまでVarS/VarA制御系のみにより調節されると考えられていたsRNAが、複数の環境シグナルを統合して演算し、多数の標的遺伝子の発現を最適化する演算システムであるというモデルを提唱した学術的意義の大変高いものである。また、VarS/VarA-sRNA制御系は細菌の病原因子の発現を調節することから、VarS/VarA-sRNA制御系の各分子を阻害する薬物は病原性発揮阻害薬の候補となり得る。したがって本研究の成果は、新規感染症治療薬の開発にも繋がり得る社会的意義も高いものである。