Live-cell imaging of a bacterial extracytoplasmic stress response and exploration of a novel function of an intramembrane protease that regulates the stress response

2016 Fiscal Year Final Research Report

• Project/Area Number: 26840033
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Functional biochemistry
• Research Institution: Kyoto University
• Principal Investigator: HIZUKURI Yohei 京都大学, ウイルス・再生医科学研究所, 助教 (70568930)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 大腸菌 / プロテアーゼ / 表層ストレス応答 / S2P / 蛍光イメージング / GFP / 生化学 / 生物物理学

Outline of Final Research Achievements

An intramembrane protease RseP is a key regulator in the σE-pathway extracytoplasmic stress response (ESR) which is critical for bacterial survival under stressed conditions. In this research project, I have aimed to understand a whole picture of the ESR system. Through a detailed functional analysis of the Escherichia coli RseP, I have revealed that two novel regions in RseP, the MRE β-loop and the C1N regions, play a crucial role for substrate recognition and cleavage mechanism. This finding gives us new insight into intramembrane cleaving proteases highly conserved from bacteria to human. We have identified some novel proteolytic substrates of RseP, which might taught us possible new roles of RseP. I have also established a live-cell imaging system for visualizing an RseP-dependent substrate cleavage event by fluorescent microscopy. This system must be useful for a kinetic analysis for the ESR system in the future.

Free Research Field

膜タンパク質科学