Mechanisms of Positive Selection on Gamete Recogntion Proteins

配子识别蛋白的正选择机制

• 批准号: 0075382
• 负责人: Michael Hellberg
• 金额: $ 9.5万
• 依托单位: Louisiana State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-12-01 至 2003-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0075382&HistoricalAwards=false
• 关键词: Mechanisms; Positive; Selection; Gamete; Recogntion

0075382HellbergProteins associated with male reproductive function typically evolve much faster than other proteins. In marine invertebrates that release their eggs and sperm directly into seawater, these male proteins, along with their egg-borne female complements, determine whether individuals and species can interbreed. Natural selection is known to promote the divergence of these male proteins between species; however, the mechanisms causing this selection--particularly the role of functionally related female proteins--remain unknown. Dr. Hellberg will evaluate proposed mechanisms for selection on the sperm protein lysin by comparing DNA sequences of the genes encoding lysin and its egg-borne receptor (VERL) from different species of the marine snail Tegula. VERL contains about 30 internal repeats of 150 amino acids, but sequences for flanking regions at the beginning and end of this protein are not known. Using molecular methods, the PI will determine DNA sequence information for VERL. He will then compare patterns of this sequence data among different species of Tegula. Patterns of VERL variation should illuminate mechanisms causing rapid change in gamete recognition proteins, in turn broadening our understanding of adaptive molecular change in general and the evolution of new, reproductively isolated species in particular. In addition, co-evolution between VERL and lysin may provide insights into the design of highly specific molecular glues (which like VERL are often composed of repeated molecular sequences).

与男性生殖功能相关的HellbergProtein通常比其他蛋白质进化得更快。在海洋无脊椎动物中，将它们的卵和精子直接释放到海水中，这些雄性蛋白，以及它们产蛋的雌性互补蛋白，决定了个体和物种是否可以杂交。众所周知，自然选择促进了这些雄性蛋白质在物种之间的差异；然而，导致这种选择的机制--特别是功能相关的雌性蛋白质的作用--仍然未知。赫尔伯格博士将通过比较不同种类的海洋蜗牛Tegula的赖氨酸及其卵载受体(VERL)编码基因的DNA序列，来评估精子蛋白赖氨酸选择的拟议机制。Verl包含大约30个由150个氨基酸组成的内部重复序列，但该蛋白开始和结束的侧翼区域的序列尚不清楚。利用分子方法，PI将确定VERL的DNA序列信息。然后，他将比较特古拉不同物种之间的序列数据模式。VERL变异的模式应该阐明导致配子识别蛋白快速变化的机制，反过来又拓宽了我们对适应性分子变化的理解，特别是对新的、繁殖隔离的物种的进化。此外，VERL和赖氨酸之间的共同进化可能会为设计高度特异性的分子胶(与VERL一样，通常由重复的分子序列组成)提供见解。