Biogenesis of regulatory sRNAs and the role of Hfq

2016 Fiscal Year Final Research Report

• Project/Area Number: 25291005
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Molecular biology
• Research Institution: Suzuka University of Medical Science
• Principal Investigator: AIBA Hiroji 鈴鹿医療科学大学, 薬学部, 教授 (20025662)
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: 小分子RNA / Hfq / Rho 非依存性ターミネーター / sRNA / バイオジェネシス / ターミネーターヘアピン

Outline of Final Research Achievements

Molecular events at Rho-independent terminators of sRNA genes have been studied, focusing on SgrS and RyhB. The 3’-extended form of SgrS loses the Hfq-binding ability. Transcription termination is significantly enhanced under stress conditions where transcription of sRNAs is induced in intact cells. We conclude that the production of sRNAs is regulated not only at the step of transcription initiation but also at the step of transcription termination.
The roles of terminator hairpin in biogenesis of sRNAs have been studied. The extension of the hairpin stem leads to generation of heterogeneous transcripts in which the polyU tail is shortened. The transcripts with shortened polyU tails no longer bind to Hfq and lose the ability to repress the target mRNAs. The generation of shortened transcripts is caused by premature transcription termination. We conclude that the terminator structure of sRNA genes is optimized to generate functional sRNAs.

Free Research Field

生物学