HERPESVIRUS PROTEINASE--POSSIBLE TARGET FOR ANTIVIRALS

描述：疱疹病毒编码一种丝氨酸成熟蛋白水解酶 这对于生产具有传染性的后代是必不可少的。这个 这种蛋白的巨细胞病毒(CMV)同源物称为集合素，是 由人巨细胞病毒UL80a开放阅读框编码。装配是 作为前体(~74 kDa)合成，经历四个序列 自身蛋白水解性卵裂。这四个裂解位点有五个氨基酸， 核心共识序列在它们的对应物中非常保守 其他疱疹病毒。组装素的主要底物是一种丰富的 衣壳组装蛋白，也包含其M-裂解位点 羧基末端，作为其有趣的框内、嵌套基因的结果 与蛋白水解酶的关系。 因为这些裂解对于病毒的产生是必不可少的，所以抑制 这种蛋白水解酶有望具有强大的抗病毒作用。新的 需要具有抗病毒活性的药物来对抗疱疹病毒，以及 本申请中提出的研究旨在进一步 确定其物理、酶和生物学特性 疱疹病毒蛋白酶，特别是CMV酶，并帮助开发它作为 药物开发的有效分子靶点。 在这次竞争性更新中提出的工作的具体目标 用途是：(I)制备蛋白酶和组装蛋白前体 用于酶分析和结晶学；ii)开发一种体外蛋白水解酶 使用“天然”底物的试验(III)确定什么裂解位点 影响切割动力学的特征；(Iv)确定相互作用的结构域 两个链组装蛋白；(V)合作研究和比较Gamma-2 HHV8 与其α(如单纯疱疹病毒)和β(如CMV)组装 疱疹病毒同系物；(Vi)在细胞培养中测试潜在的抗病毒药物；以及 (Vii)确定病毒“逃避”其影响的能力。 这项工作的结果预计将为以下方面提供有用的新信息 这显然是丝氨酸蛋白酶家族的新成员，并有助于 开发出能阻断其功能的抑制剂。它也是 很可能会在病毒领域产生有用的新信息 蛋白酶机制与疱疹病毒复制。

DESCRIPTION: Herpes-group viruses encode a serine maturational proteinase that is essential for the production of infectious progeny. The cytomegalovirus (CMV) homologue of this protein is called assemblin and is encoded by the UL80a open reading frame in human CMV. Assemblin is synthesized as a precursor (~74kDa) that undergoes four sequential autoproteolytic cleavages. The four cleavage sites have five amino acid, core consensus sequences that are well conserved among their counterparts in other herpes virus. The principal substrate of assemblin is an abundant capsid assembly protein that also contains the M-cleavage site at its carboxyl end, as a consequence of its interesting in-frame, nested genetic relationship with the proteinase. Because these cleavages are essential for virus production, inhibition of the proteinase would be expected to have a potent antiviral effect. New drugs with antiviral activity against herpes-group viruses are needed, and the studies proposed in this application are intended to further characterize the physical, enzymatic, and biological properties of the herpesvirus proteinase, in particular the CMV enzyme, and help exploit it as an effective molecular target for drug development. The specific aims of the work proposed in this competitive renewal application are: (i) prepare proteinase and assembly protein precursors for use in enzyme assays and crystallography; ii) develop an in vitro proteinase assay that uses "native" substrate' (iii) determine what cleavage-site features influence cleavage kinetics; (iv) identify the interactive domains of two chain assemblin; (v) collaborate to study and compare gamma-2 HHV8 assemblin with its alpha (e.g., herpes simplex virus) and beta (e.g., CMV) herpesvirus homologues; (vi) test potential antivirals in cell culture; and (vii) determine the ability of virus to "escape" their effect. Results of this work are anticipated to provide useful new information about this apparently novel member of the serine proteinase family, and contribute to the development of inhibitors that will block its function. It is also likely that useful new information will be generated in the areas of viral proteinase mechanisms and herpesvirus replication.