EVOLUTION OF THE RIBONUCLEASE SUPERFAMILY

描述：这笔赠款的目标是制定一项新的战略 在蛋白质中将生理功能与生化行为结合起来。这 方法将蛋白质的结构、机制和工程学与 进化论分析。这一分析的核心是重建 来自序列数据的蛋白质超家族的进化历史，以及 在实验室里从灭绝的生物体中制备古代蛋白质 它们是可以研究的。分子和生物行为的进化是 设置在历史背景下，将其与 生物体(源自古生物学)和周围的生态，允许 关于结构-行为的可验证性假设的构造 在这个家族中的关系，这些化合物发挥作用的机制 它们的生物学活动，以及可能的生理功能(S) 蛋白质，以及允许对所需的新蛋白质进行工程 行为。这里的工作将使用核糖核酸酶作为一种系统来开发这种 策略。牛胰腺核糖核酸酶A属于蛋白质超家族 在不同的成员中，这已经演变成了一系列有趣的 生物学行为。已知的核糖核酸酶同系物具有免疫抑制作用， 阻断肿瘤细胞(但不是正常细胞)的生长，杀死血吸虫和 旋毛虫引起神经损伤，导致哮喘患者肺损伤 患者表现出凝集素样行为，抑制哺乳动物细胞的感染 被HIV-1感染，或者什么都不做。这些行为与医学有关； 几种核糖核酸酶变体目前正处于临床和临床前测试阶段 因为他们有用的生物医学活动。在正在进行的下一阶段 研究计划，生物行为的生理学意义 将对种子核糖核酸酶进行评估，解决晶体结构问题以确定 精液核糖核酸酶结合和融化双链DNA的机制， 介绍了半胱氨酸对折叠动力学的影响以及半胱氨酸对折叠的影响。 将对褶皱结构的热力学进行研究，并对新的序列 将收集数据以完成生物进化历史的模型 这类重要的分子。这项研究将展示新的 生物分子功能是在高等生物体中通过突变而产生的， 插入、缺失、基因复制和重复基因的招募。 这种进化方法不同于其他实验室所采用的方法， 这项工作将继续发展一种新的范式，即进化 将信息与化学和生物信息整合起来解决 “后基因组”环境下的生物医学研究问题。

DESCRIPTION: The goal of this grant is to develop a new strategy for joining physiological function to biochemical behavior in proteins. This approach combines protein structure, mechanism, and engineering with evolutionary analyses. Central to this analysis is the reconstruction of evolutionary history of the protein superfamily from sequence data, and preparing ancient proteins from extinct organisms in the laboratory where they can be studied. The evolution of molecular and biological behavior is set in a historical context by correlating it with the evolution of organisms (deduced from paleontology) and the surrounding ecology, allowing construction of testable hypotheses concerning the structure-behavior relationships in this family, mechanisms by which these compounds exert their biological activities, and possible physiological function(s) of the proteins, as well as allowing to engineer new proteins with desired behaviors. The work here will use ribonuclease as a system to develop this strategy. Bovine pancreatic RNase A belongs to a superfamily of proteins that has, in various members, evolved to an enormous range of interesting biological behaviors. RNase homologs are known that are immunosuppressive, block the growth of tumor cells (But not normal cells), kill Schistosoma and Trichinella, cause neurological damage, cause lung damage in asthmatic patients, display lectin-like behavior, inhibit infection of mammalian cells by HIV-1, or do none of these. These behaviors have medical relevance; several RNase variants are now in clinical and preclinical stages of testing for their useful biomedical activities. In the next phase of this ongoing research program, the physiological significance of biological behaviors of seminal RNase will be assessed, a crystal structure solved to determine the mechanism by which seminal RNase binds and melts duplex DNA, the impact of the introduction of cysteines on the kinetics of folding and the thermodynamics of the folded structure will be examined and new sequence data will be collected to complete the model of the evolutionary history of this important class of molecules. This study will show how new biomolecular function is created in higher organisms, by mutation, insertion, deletion gene duplication and recruitment of duplicate genes. This evolutionary approach differs from that pursued in other laboratories, and this work will continue to develop a new paradigm where evolutionary information is integrated with chemical and biological information to solve biomedical research problems in a "post-genome" environment.