PHAGE T4 HEAD ASSEMBLY AND INITIATION OF INFECTION

该应用程序提出了对病毒结构和组装的研究。 的 DNA被包装在病毒衣壳内的机制，以及 将研究这种浓缩的DNA的结构。 DNA如何包装 机制与病毒DNA代谢相互作用，特别是DNA修复， 将在体外研究感染细胞中的重组过程。 显示DNA包装和重组的提取物。 电子 显微镜将用于在体内研究DNA包装的过程， 病毒组装和DNA结构，以及病毒的后果， 双链DNA结构中病变的DNA包装。 一种头部组件， 从病毒感染的细胞中纯化的DNA依赖性ATP酶-内切核酸酶 将研究其对DNA结构的影响及其在DNA中的作用 包装过程。 其他已知参与的病毒基因产物 将DNA连接到原病毒结构将被纯化， 对DNA和DNA入口顶点结构蛋白的特异性 将确定衣壳。 涉及病毒DNA代谢基因产物 在感染的早期，DNA合成将被检查， 在无细胞病毒感染提取物系统中的体外重组。 将研究病毒衣壳形成的早期阶段，特别是 强调衣壳壳形成和头部扩张的能量学 通过微量热法测定。 突变体的基础是 将确定某些病毒DNA包装基因产物。 如果像 初步证据使我们提出，一些病毒DNA包装发生在 通过酶促过程，这一步骤可能受到病毒特异性 抑制作用 对这些过程的了解将有助于我们了解DNA 在病毒感染和正常细胞中的凝聚、运动和代谢， 并且是真核染色体浓缩的模型。

The application proposes research on virus structure and assembly. The mechanism by which DNA is packaged within the viral capsid, and the structure of this condensed DNA will be studied. How the DNA packaging mechanism interacts with viral DNA metabolism, specifically DNA repair and recombination processes, in the infected cell will be studied in vitro in an extract which displays both DNA packaging and recombination. Electron microscopy will be used to study in vivo the process fo DNA packaging, viral assembly, and DNA structure, as well as the consequences for viral DNA packaging of lesions in duplex DNA structure. A head assembly related DNA dependent ATPase-endonuclease purified from the viral infected cell will be examined for its effect upon DNA structure and its role in the DNA packaging process. Other viral gene products known to be involved in linking DNA to the provirus structure will be lpurified, and their binding specificity to DNA and to the DNA entrance vertex structural protein of the capsid will be determined. Viral DNA metabolism gene products involved early in infection in DNA synthesis will be examined for their involvement in in vitro recombination in the cellfree viral infected extract system. Early stages in viral capsid formation will be studied, with particular emphasis upon the energetics of capsid shell formation and head expansion as determined by microcalorimetry. The basis for mutants which overproduce certain viral DNA packaging gene products will be determined. If, as preliminary evidence has led us to propose, some viral DNA packaging occurs by an enzymatic process, this step might be subject to viral specific inhibition. Knowledge about these processes will shed light upon DNA condensation, movement, and metabolism in virus infected and normal cells, and is a model for eucaryotic chromosome condensation.