Studies of E. coli Min proteins

描述（由申请人提供）：本项目的长期目标是确定细菌在中细胞选择适当细胞分裂位点的机制。三种Min蛋白，MinC，MinD和MinE，是正确的位点选择所必需的。这些蛋白质具有独特的细胞定位模式，并经历独特的极到极振荡周期。我们最近发现，MinCDE蛋白被组织成螺旋丝，这些螺旋丝在两极之间缠绕在细胞周围，形成一种类似细胞质的结构，这种结构与MreB蛋白形成的卷曲结构不同。在建议的资助期内，我们将使用荧光显微镜、生物化学和遗传学的组合，以实现以下目标：最小蛋白质的结构和功能-为了确定干扰MinCDE系统的拓扑特异性功能的突变的影响，ii. Min系统的远程组织--为了定义细胞内MinDE细胞间隙样元件的组织，以确定Min和MreB螺旋丝是否是单独的结构，以表征与MinD和MinE相互作用的蛋白质，并确定Min螺旋丝和染色体分离之间是否存在关系，iii. MreB--分离MreB和Min细胞间隙样结构，表征与MreB相互作用的蛋白质，并确定细胞周期过程中MreB细胞间隙样结构的行为。

DESCRIPTION (provided by applicant): The long-range goal of this project is to determine the mechanism used by bacteria to select the proper cell division site at midcell. The three Min proteins, MinC, MinD and MinE, are required for proper site selection. The proteins have a unique cellular localization pattern and undergo a unique pole-to-pole oscillatory cycle. We have recently shown that the MinCDE proteins are organized into spiral filaments that wind around the cell between the two poles in a cytoskeletal-like structure that appears distinct from a coiled structure formed by the MreB protein. During the proposed grant period we will use a combination of fluorescence microscopy, biochemistry and genetics to achieve the following aims: i. Min protein structure and function-- To determine the effects of mutations that interfere with the topological specificity function of the MinCDE system, ii. Long-range organization of the Min system-- To define the organization of the MinDE cytoskeletal-like elements within the cell, to determine whether the Min and MreB spiral filaments are separate structures, to characterize proteins that interact with MinD and MinE, and to determine whether there is a relationship between the Min spiral filaments and chromosome segregation, iii. MreB-- To isolate the MreB and Min cytoskeletal-like structures, to characterize proteins that interact with MreB, and to define the behavior of the MreB cytoskeletal-like structures during the course of the cell cycle.