Virus Chromosome Structure: Role in Development

病毒染色体结构：在发育中的作用

• 批准号: 6796753
• 负责人: MICHAEL FEISS
• 金额: $ 39.03万
• 依托单位: UNIVERSITY OF IOWA
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-08-01 至 2006-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6796753
• 关键词: DNA binding protein; bacteriophage lambda; chromosomes; endodeoxyribonuclease; gene mutation; intermolecular interaction; protein purification; virus DNA; virus assembly; virus genetics; virus protein

DESCRIPTION (provided by applicant): Bacteriophage Lambda is an excellent model system for studying virion assembly for the large DNA viruses, including the herpes, pox and adenoviruses. These viruses assemble empty protein shells into which the viral chromosome is packaged. In addition, during DNA packaging of many lambdoid phages and the herpes viruses, long end-to-end polymers of viral DNA are cut at specific sites to generate unit-length molecules.Viral DNA is selected for packaging from a DNA pool that also includes host sequences. This recognition is governed by the interactions of viral packaging proteins with a set of protein binding sites on the viral DNA. How protein-DNA interactions orchestrate packaging is best understood for . We propose to further define these DNA-protein interactions, which have broad implications for virus DNA recognition. We also seek to understand the mechanism of an assembly catalyst that aids recognition steps.While the functioning of the viral DNA packaging enzyme, terminase, has been extensively studied, the role of the shell, especially the shell's portal vertex, has not. We propose experiments on the portal's role in packaging, and seek to define the portal's binding site for terminase. As part of this work we plan to examine the roles of several proteins involved in shell assembly. This work will generate purified packaging proteins and assemblages suitable for structural analysis. Structural information about packaging proteins is crucial for understanding the wealth of genetic information and to assist in design of further studies on the functioning of these proteins.The mechanism of how DNA is translocated into the shell is not understood in any virus system. We propose molecular studies on a series of mutants that have defects in DNA packaging, including DNA translocation. We will also look at the ability of terminase to move DNA, and to pursue a structural analysis of functional domains of terminase.

描述（由申请人提供）：噬菌体 Lambda 是用于研究大型 DNA 病毒（包括疱疹病毒、痘病毒和腺病毒）的病毒体组装的优秀模型系统。这些病毒组装空蛋白壳，将病毒染色体包装在其中。此外，在许多羔羊噬菌体和疱疹病毒的 DNA 包装过程中，病毒 DNA 的长端对端聚合物在特定位点被切割，生成单位长度的分子。从还包括宿主序列的 DNA 库中选择病毒 DNA 进行包装。这种识别是由病毒包装蛋白与病毒 DNA 上一组蛋白结合位点的相互作用控制的。蛋白质-DNA 相互作用如何协调包装最适合理解。我们建议进一步定义这些 DNA-蛋白质相互作用，这对病毒 DNA 识别具有广泛的影响。我们还试图了解有助于识别步骤的组装催化剂的机制。虽然病毒 DNA 包装酶、终止酶的功能已被广泛研究，但外壳的作用，尤其是外壳的门户顶点，尚未得到广泛研究。我们建议对门户在包装中的作用进行实验，并寻求定义门户的终止酶结合位点。作为这项工作的一部分，我们计划检查参与壳组装的几种蛋白质的作用。这项工作将产生适合结构分析的纯化包装蛋白和组合物。有关包装蛋白的结构信息对于理解丰富的遗传信息和协助设计这些蛋白功能的进一步研究至关重要。在任何病毒系统中，DNA 如何转运到外壳的机制尚不清楚。我们建议对一系列 DNA 包装缺陷（包括 DNA 易位）的突变体进行分子研究。我们还将研究终止酶移动 DNA 的能力，并对终止酶的功能域进行结构分析。