EVOLUTION OF THE RIBONUCLEASE SUPERFAMILY

核糖核酸酶超家族的进化

• 批准号: 6019139
• 负责人: STEVEN A BENNER
• 金额: $ 13.8万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6019139
• 关键词: DNA binding protein; X ray crystallography; biochemical evolution; crystallization; disulfide bond; endoribonucleases; enzyme activity; isozymes; protein binding; protein engineering; protein folding; protein sequence; protein structure function; structural biology; thermodynamics

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.

描述：这笔赠款的目标是制定一项新战略 将蛋白质的生理功能与生化行为结合起来。 这 方法将蛋白质结构、机制和工程结合起来 进化分析。 该分析的核心是重建 根据序列数据了解蛋白质超家族的进化史，以及 在实验室中从已灭绝的生物体中制备古代蛋白质 他们可以被研究。 分子和生物行为的进化是 将其与历史的演变联系起来 生物（从古生物学推论）和周围的生态，允许 构建有关结构行为的可检验假设 该家族中的关系，这些化合物发挥作用的机制 它们的生物活性以及可能的生理功能 蛋白质，以及允许设计具有所需的新蛋白质 行为。 这里的工作将使用核糖核酸酶作为系统来开发这个 战略。 牛胰腺 RNase A 属于蛋白质超家族 在不同的成员中，它已经发展成为一系列有趣的 生物行为。 已知 RNase 同源物具有免疫抑制作用， 阻止肿瘤细胞（但不包括正常细胞）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 感染 HIV-1，或者不做这些。 这些行为具有医学相关性； 几种 RNase 变体目前正处于临床和临床前测试阶段 因其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 将评估精液 RNase，解析晶体结构以确定 精液 RNase 结合和熔化双链 DNA 的机制， 半胱氨酸的引入对折叠动力学的影响 将检查折叠结构的热力学和新的序列 将收集数据以完成进化历史模型 这一类重要的分子。 这项研究将展示如何新 生物分子功能是通过突变在高等生物体中产生的， 插入、删除基因复制和重复基因的招募。 这种进化方法与其他实验室所采用的方法不同， 这项工作将继续开发一种新的范式，其中进化 信息与化学、生物信息集成，解决 “后基因组”环境中的生物医学研究问题。