大肠杆菌pH震荡信号的调控机制及功能研究

质子（H+）一方面是重要的信使物质，另一方面胞内pH的相对稳定对于细胞维持正常的生理功能非常重要。大肠杆菌作为单细胞生物，为了应对周围环境复杂的pH变化，进化发展了严格的pH稳态调控机制。我们的前期研究在单个大肠杆菌中发现了自发的、瞬态的pH碱化现象，将其命名为“pH震荡（E.coli flash, eFlash）”。本课题将在此研究基础上，利用高分辨率激光共聚焦显微成像技术，全面深入研究pH震荡这一全新的生理动态信号，重点研究pH震荡信号在大肠杆菌pH稳态调控及生长中的作用，并进一步结合RNA深度测序技术解析pH震荡信号在细菌基因转录调控中的作用，从新的视角解析pH稳态调控及基因转录调控的新机制。另外，本课题还将在全基因组水平筛选pH震荡信号的关键调控蛋白，从分子水平剖析pH震荡信号的产生与调控机制。

Proton is an important kind of messengers, and it is essential for a cell to maintain its pH homeostasis. As a single cell organism, E.coli has developed a complex pH homeostasis network to counteract the changes of environmental pH. Recently, we found a spontaneous and transient pH alkalization in a single E.coli and we named it as “eFlash”. In this project, we will comprehensively study the regulations and functions of eFlashes with the aid of high resolution confocal imaging. Especially, we will focus on illustrating the roles of eFlashes in pH homeostasis and growth. Further, we will study the functions of eFlashes in regulating gene transcription by using RNA-seq. These studies will provide new mechanisms for pH homeostasis and gene transcription of E.coli. Meanwhile, we will identify the key eFlash regulatory proteins by a whole-genome screening, uncovering the mechanisms of eFlash generation and regulation.