Targeting and assembly of E. coli cell division proteins

大肠杆菌细胞分裂蛋白的靶向和组装

• 批准号: 7924945
• 负责人: WILLIAM MARGOLIN
• 金额: $ 35.4万
• 依托单位: UNIVERSITY OF TEXAS HLTH SCI CTR HOUSTON
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-30 至 2010-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7924945
• 关键词: Actins; Address; Affect; Bacteria; Bypass; Cell Size; Cell division; Cell physiology; Cells; Chromosome Segregation; Chromosomes; Contracts; Cytokinesis; Cytoplasm; Data; Daughter; Escherichia coli; Event; Genes; Genetic; Goals; Grant; Image; Individual; Knowledge; Location; Membrane; Modeling; Molecular; Molecular Machines; Mutation; Pathway interactions; Protein Biochemistry; Proteins; Recruitment Activity; Recycling; Research; Rest; Role; Set protein; Site; Structure; Surface; Testing; Time; Tubulin; Work; antimicrobial; base; constriction; cost; frontier; gain of function; mutant; programs; protein function; protein protein interaction; reconstitution; stoichiometry

Before any cell divides to yield viable daughters, it must first separate its duplicated chromosomes and split its cytoplasm between them. This fundamentally important event, cytokinesis, must occur at the correct time, after chromosome segregation, and place, between the segregated chromosomes. In bacteria, cytokinesis is orchestrated by an essential and highly conserved tubulin-like protein, FtsZ, which assembles into a circumferential ring structure, called the Z-ring, on the inner membrane at the cell midpoint. Once assembled, the Z-ring of E. coli then recruits at least 10 additional essential division proteins to the membrane at the developing division site, after which the ring contracts at the leading edge of the growing septal wall to split the cell into two. Surprisingly, the molecular roles of most of these proteins in the functioning of the cell division machine are unknown. It is also unclear how the various proteins in the machine recruit and stabilize each other, or how the Z ring is triggered to contract once the machine is assembled. Our previous work has shown that some of these proteins can be eliminated with little cost by changing the activities of other proteins, indicating that the cell division machine may be overbuilt. We seek to understand the function of the proteins in the machine by distinguishing the core components from the regulatory components. Our approach utilizes genetics, protein biochemistry, and imaging of whole cells. Specifically, we propose to (i) understand how FtsZ assembly is regulated by cell division proteins such as the actin-like FtsA; (ii) define how FtsZ and FtsA recruit and build the rest of the machine via a cooperative network of protein-protein interactions; and (iii)strip down the rest of the machine to its core components using genetics. The study of bacterial cell division is important not only because it is a basic cellular process that needs to be understood, but also because cytokinesis is an important potential target of antimicrobials.

在任何细胞分裂产生可存活的子细胞之前，它必须首先分离其复制的染色体并分裂