Molecular basis of adaptation of seminal proteins of humans and other primates

项目摘要 我们体内的2万个蛋白质编码基因是由突变的综合力量塑造的。 自然选择、基因漂移和迁徙。理解这些力量的影响的一个重要途径， 特别是单个氨基酸突变对蛋白质功能的影响，是比较 我们的基因和蛋白质与我们最亲近的亲戚的基因和蛋白质相匹配。在这样做的过程中，选择模式(积极 选择、否定选择或约束的放松)也可以被推断。在过去的十年里，超过一个 十几个高质量的灵长类基因组序列已经公布，允许详细研究 用复合体作用于人类基因组和其他原始人基因组的进化力 基于种群遗传学和分子进化原理的模型。在这项拟议的研究中， 我们将通过执行定量功能分析来超越选择的计算预测 重组蛋白和合成肽用于测定催化效率和底物的差异 人类精液中发现的高度丰富的胞外蛋白的特异性。这样的蛋白质通常是 通过计算预测成为正选择、净化选择和伪基因化的目标 在原始人灵长类(人类和类人猿)中。 实验设计将包括测试来自人类的重组蛋白的功能， 黑猩猩、大猩猩和猕猴。此外，我们将创建与最后一个相对应的蛋白质 人类和黑猩猩；人类、黑猩猩和大猩猩的共同祖先；猕猴的共同祖先 和原始人，使用祖先序列重建。对于这些物种中的每一个，我们将测量 前列腺酸性磷酸酶ACPP的磷酸酶和多肽酶活性，前列腺酶活性 前列腺表达KLK3，前列腺谷氨酰胺转氨酶TGM4活性。此外，效率 这些酶中的每一种都将使用它们的天然底物精囊进行测试 表达了SEMG1和SEMG2，以了解它们的共同进化。除了检查差异之外 在酶活性的物种之间，我们将检验这样的假设，即物种在小分子的能力上存在差异 源自ACPP、SEMG1和SEMG2的多肽，可形成淀粉样纤维并增强HIV感染。 最后，我们将使用生物信息学的方法来识别灵长类基因的进化可能 由性选择或对性传播病毒的抵抗力驱动。 这项研究将通过让学生接触到以下知识来改善杜肯大学的本科教育 有功研究的同时，显著改善了国际和平研究所实验室的研究环境， 系和大学。

Project Summary The >20,000 protein-coding genes in our body have been shaped by the combined forces of mutation, natural selection, genetic drift, and migration. An essential way to understand the effects of these forces, especially the consequences of individual amino acid-changing mutations on protein function, is to compare our genes and proteins to those of our closest relatives. In doing so, the mode of selection (positive selection, negative selection, or relaxation of constraint) can also be inferred. Over the last decade, over a dozen high-quality primate genome sequences have been published, allowing for detailed investigation of the forces of evolution acting on the human genome and the genomes of other hominids, using complex models based on the principles of population genetics and molecular evolution. In the proposed research, we will go beyond computational predictions of selection by performing quantitative functional assays using recombinant proteins and synthetic peptides to measure differences in catalytic efficiency and substrate specificity of high-abundant extracellular proteins found in human semen. Such proteins have often been predicted computationally to be the targets of positive selection, purifying selection, and pseudogenization among the hominid primates (humans and the great apes). The experimental design will include testing the function of recombinant proteins from humans, chimpanzees, gorillas, and macaques. Furthermore, we will create the proteins corresponding to the last common ancestors of humans and chimpanzees; of humans, chimpanzees, and gorillas; and of macaques and the hominids, using ancestral sequence reconstruction. For each of these species, we will measure the phosphatase and peptidase activity of the prostatic acid phosphatase ACPP, the protease activity of the prostate expressed KLK3, and the transglutaminase activity of prostatic TGM4. Furthermore, the efficiency and specificity each of these enzymes will be tested using their natural substrates, the seminal vesicle expressed SEMG1 and SEMG2, to understand their coevolution. In addition to examining differences among species in enzyme activity, we will test the hypothesis that species differ in the ability of small peptides derived from ACPP, SEMG1, and SEMG2 to form amyloid fibrils and enhance HIV infection. Finally, we will use bioinformatics approaches to identify primate genes whose evolution may have been driven by either sexual selection or resistance to sexually transmitted viruses. This research will improve undergraduate education at Duquesne University by exposing students to meritorious research while significantly enhancing the research environment of the PI's laboratory, department, and university.