Quantitative analysis of intracellular signaling for environmental stimuli in a single E. coli cell

2016 Fiscal Year Final Research Report

• Project/Area Number: 26440073
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Biophysics
• Research Institution: Osaka University (2015-2016); Tohoku University (2014)
• Principal Investigator: FUKUOKA Hajime 大阪大学, 生命機能研究科, 准教授 (50447190)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: 走化性 / 感覚受容 / 情報伝達

Outline of Final Research Achievements

This study measured the cellular response for the extracellular stimulus utilizing the controlled photo-cleavage of caged-serine under high speed imaging. By this measurement, it was revealed the intracellular signal would be performed by the propagation of the decrease in the concentration of CheY-P (signal molecule) and this propagation was performed due to the dephosphorylation of CheY-P by polar localized CheZ and diffusion of CheY-P molecules. By the simultaneous measurement of the time difference between two motors on the same cell and comparison it between wild-type and mutant cells, the dynamic change in CheY-P concentration directly regulates the rotational direction of motor in the absence of extracellular stimuli. The functional CheY-GFP fusion as the intracellular signal molecule could be constructed, however, the cell expressing this fusion unexpectedly exhibited repellent response to the excitation light for GFP. This problem should be untied to progress this study.

Free Research Field

生物学