EVOLUTION OF THE RIBONUCLEASE SUPERFAMILY

描述：这项赠款的目标是制定一项新的战略， 将蛋白质的生理功能与生化行为结合起来。 这 方法结合蛋白质结构，机制和工程， 进化分析 这一分析的核心是重建 蛋白质超家族的进化历史， 在实验室里从灭绝的生物体中制备古老的蛋白质， 可以研究。 分子和生物行为的进化是 在历史背景下，通过将其与 生物（从古生物学推导）和周围的生态，允许 构造关于结构-性能的可检验假设 这些化合物发挥作用的机制 它们的生物活性，以及它们的可能生理功能， 蛋白质，以及允许工程新的蛋白质与所需的 行为。 这里的工作将使用核糖核酸酶作为一个系统来开发这个 战略 牛胰腺核糖核酸酶A属于蛋白质超家族 在不同的成员中， 生物行为。 已知RNA酶同系物具有免疫抑制作用， 阻断肿瘤细胞的生长（但不是正常细胞），杀死血吸虫， 旋毛虫，引起神经系统损害，引起哮喘肺损害 患者，显示凝集素样行为，抑制哺乳动物细胞的感染 或者什么都不做 这些行为具有医学相关性; 几种核糖核酸酶变体目前正处于临床和临床前测试阶段 他们有用的生物医学活动。 在这个正在进行的下一阶段， 研究计划，生物行为的生理意义 精液核糖核酸酶将被评估，晶体结构解决，以确定 精液核糖核酸酶结合和熔化双链体DNA的机制， 半胱氨酸的引入对折叠动力学的影响， 折叠结构的热力学将被检查和新的序列 将收集数据，以完成进化历史的模型， 这类重要的分子 这项研究将展示新的 生物分子的功能是在高等生物体中通过突变产生的， 插入、缺失基因复制和重复基因的募集。 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模式， 信息与化学和生物信息相结合， 在“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.