Mueller Jacob L, Ripoll Daniel R, Aquadro Charles F, Wolfner Mariana F
Department of Molecular Biology and Genetics, Biotechnology Building, Cornell Theory Center, Cornell University, Ithaca, NY 14853, USA.
Proc Natl Acad Sci U S A. 2004 Sep 14;101(37):13542-7. doi: 10.1073/pnas.0405579101. Epub 2004 Sep 2.
The constituents of seminal fluid are a complex mixture of proteins and other molecules, most of whose functions have yet to be determined and many of which are rapidly evolving. As a step in elucidating the roles of these proteins and exposing potential functional similarities hidden by their rapid evolution, we performed comparative structural modeling on 28 of 52 predicted seminal proteins produced in the Drosophila melanogaster male accessory gland. Each model was characterized by defining residues likely to be important for structure and function. Comparisons of known protein structures with predicted accessory gland proteins (Acps) revealed similarities undetectable by primary sequence alignments. The structures predict that Acps fall into several categories: regulators of proteolysis, lipid modifiers, immunity/protection, sperm-binding proteins, and peptide hormones. The comparative structural modeling approach indicates that major functional classes of mammalian and Drosophila seminal fluid proteins are conserved, despite differences in reproductive strategies. This is particularly striking in the face of the rapid protein sequence evolution that characterizes many reproductive proteins, including Drosophila and mammalian seminal proteins.
精液的成分是蛋白质和其他分子的复杂混合物，其中大多数功能尚未确定，而且许多成分正在迅速进化。作为阐明这些蛋白质的作用以及揭示其快速进化所掩盖的潜在功能相似性的一个步骤，我们对果蝇雄性附腺产生的52种预测精液蛋白中的28种进行了比较结构建模。每个模型通过定义可能对结构和功能重要的残基来表征。已知蛋白质结构与预测的附腺蛋白（Acps）的比较揭示了通过一级序列比对无法检测到的相似性。这些结构预测Acps可分为几类：蛋白水解调节因子、脂质修饰剂、免疫/保护、精子结合蛋白和肽激素。比较结构建模方法表明，尽管生殖策略存在差异，但哺乳动物和果蝇精液蛋白的主要功能类别是保守的。面对许多生殖蛋白（包括果蝇和哺乳动物精液蛋白）所特有的快速蛋白质序列进化，这一点尤其引人注目。
