Assembly and partition mechanism of Walker-box based segregation machinery

基于Walker-box的分离机械的组装和分离机构

• 批准号: 9118256
• 负责人: Maria Schumacher
• 金额: $ 30.93万
• 依托单位: DUKE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-08-01 至 2019-04-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9118256
• 关键词: Antibiotics; Archaea; Automobile Driving; Bacterial Model; Bacterial Typing; Binding; Binding Proteins; Biochemical; Biological Models; Biology; Boxing; Cells; Centromere; Chromosomes; Complex; Cytoskeletal Filaments; DNA; DNA Binding; Data; Deposition; Disease; Dissection; Elements; Employee Strikes; Ensure; Epitopes; Eukaryota; Generations; Genetic Materials; Goals; Histone Fold; Histone H3; Histones; Homologous Gene; Human; Image; Infection; Life; Lighting; Link; Maintenance; Mediating; Microscopy; Modeling; Molecular; Multi-Drug Resistance; Nucleic Acids; Nucleosomes; Organism; Plasmids; Process; Prokaryotic Cells; Proteins; Resistance; Resolution; Site; Structure; System; Therapeutic Intervention; Walkers; base; genetic information; in vivo; in vivo imaging; novel; nucleoside triphosphatase; polymerization; protein complex; public health relevance; segregation

 DESCRIPTION (provided by applicant): DNA segregation or partition is one of the most fundamental processes in biology and ensures that genetic information is accurately retained from one generation to the next. While the molecules involved in partition have largely been identified in prokaryotes and eukaryotes, the mechanisms that drive this process are not understood at the atomic level. Moreover, currently, very little is known about DNA segregation in archaea. The overarching goals of this proposal are to define the molecular mechanisms and principles involved in DNA segregation using model bacterial and archaeal partition (par) systems. Bacterial plasmid par systems represent excellent model systems to study segregation at an atomic level because they minimally require only 3 elements, a centromere, a centromere-binding protein (CBP) and an NTPase. The most common par system is the so-called type I, or Walker-box based system. This type of par system is involved in the partitioning of both prokaryotic chromosomes and plasmids, and includes CBPs called ParB and Walker-type NTPases called ParA. Our recent combination of structural and in vivo super-resolution studies has started to provide a detailed atomic as well as dynamic understanding of bacterial segregation. Eukaryotes appear to use machinery distinct from prokaryotes whereby their centromeres are marked by "centromeric nucleosomes", which contain CenpA in the place of histone H3 along with H4, H2A and H2B. Although these systems seem vastly disparate, our recent studies have revealed structural and, potentially, functional links between DNA segregation in the 3 domains of life. Specifically, our initial characterization of the first archaa par system, pNOB8, reveals that it employs a Walker-box NTPase similar to those used by prokaryotes while our preliminary structure of the pNOB8 ParB reveals that it contains a fold similar to the eukaryotic histone CenpA protein. Based on these findings, we hypothesize that shared structural and functional principles may exist in DNA segregation mechanisms across the domains of life. The goals of this proposal are to provide detailed structural and functional dissections of DNA segregation using two prototypical model systems; the bacterial TP228 par system and the archaeal pNOB8 par system.

 描述（由应用程序提供）：DNA分离或分区是生物学中最基本的过程之一，并确保将遗传信息准确地保留在一代中。虽然在原核生物和真核生物中已经在很大程度上鉴定出参与分区的分子，但在原子水平上尚不清楚驱动这一过程的机制。此外，目前，关于古细菌的DNA隔离知之甚少。该提案的总体目标是定义使用模型细菌和存档分区（PAR）系统参与DNA分离的分子机制和原理。细菌质粒PAR系统代表了在原子水平上研究隔离的出色模型系统，因为它们最小需要3个元素，一个丝粒，共粒结合蛋白（CBP）和NTPase。最常见的PAR系统是所谓的I型或基于Walker-Box的系统。这种类型的PAR系统参与了原核生物染色体和质粒的分配，并包括称为PARB和Walker型NTPases的CBP，称为PARA。我们最近将结构和体内超分辨率研究结合起来，开始提供详细的原子和动态理解细菌分离。真核生物似乎使用了不同于原核生物的机械，从而将其centrokarees标记为“ centromeric核小体”，其中包含CENPA，代替组蛋白H3以及H4，H2A和H2B。尽管这些系统似乎截然不同，但我们最近的研究揭示了生命三个领域的DNA分离之间的结构性和可能的​​功能联系。具体而言，我们对第一个ARCHAA PAR系统PNOB8的最初表征表明，它采用了与原核生物相似的Walker-Box NTPase，而PNOB8 PARB的初步结构表明，它包含与真核组织组蛋白蛋白蛋白相似的折叠。基于这些发现，我们假设在整个生命领域的DNA隔离机制中可能存在共同的结构和功能原理。该提案的目标是使用两个原型模型系统提供DNA分离的详细结构和功能解剖。细菌TP228 PAR系统和古细菌PNOB8 PAR系统。