Studies of E. coli Min proteins

描述（由申请人提供）：该项目的长期目标是确定细菌用于选择中细胞正确细胞分裂位点的机制。正确的位点选择需要三种 Min 蛋白：MinC、MinD 和 MinE。这些蛋白质具有独特的细胞定位模式，并经历独特的极对极振荡周期。我们最近表明，MinCDE 蛋白被组织成螺旋丝，以细胞骨架样结构缠绕在两极之间的细胞周围，该结构与 MreB 蛋白形成的卷曲结构不同。在拟议的资助期内，我们将结合使用荧光显微镜、生物化学和遗传学来实现以下目标： Min 蛋白质结构和功能——确定干扰 MinCDE 系统拓扑特异性功能的突变的影响，ii。 Min系统的远程组织——定义细胞内MinDE细胞骨架样元件的组织，确定Min和MreB螺旋丝是否是独立的结构，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 细胞骨架样结构，表征与 MreB 相互作用的蛋白质，并定义 MreB 细胞骨架样结构在细胞周期过程中的行为。

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.