ABALONE EGG COAT PROTEINS

该子项目是利用 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得主要资金， 因此可以在其他CRISP条目中表示。列出的机构是 中心，不一定是研究者的机构。 具有透明质酸（ZP）结构域的蛋白质是脊椎动物卵壳的主要组分。 虽然不太好的特点，卵外套的无脊椎动物海洋腹足类鲍鱼（鲍属）。也已知含有ZP结构域蛋白，提高了后生动物卵外壳结构的共同分子基础的可能性。 来自脊椎动物和无脊椎动物分类群的卵外壳蛋白已经被证明在正选择下进化。 在鲍鱼系统中研究最广泛的是，适应性分化的卵外壳和精子蛋白之间的协同进化可能有助于生殖隔离的快速发展。 因此，确定蛋壳蛋白之间的进化模式是重要的，在了解这些基因可能在物种形成过程中发挥的作用。 本研究的目的是表征鲍鱼卵的卵被（卵黄囊，VE）的组成蛋白，并提供初步证据，关于选择如何在鲍鱼进化过程中作用于VE蛋白。 我们使用蛋白质组学的方法来匹配串联质谱的肽从纯化的VE蛋白与鲍鱼卵巢EST序列，并确定9的10个新的ZP结构域蛋白的组成部分的VE。 密码子进化的最大似然模型表明正选择在这些基因中的6个的氨基酸子集中起作用。 这项工作提供了进一步的证据，突出的ZP蛋白质的成分的卵外套，以及突出的作用，积极选择多样化的这些生殖蛋白。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Proteins harboring a zona pellucida (ZP) domain are prominent components of vertebrate egg coats. Although less well characterized, the egg coat of the invertebrate marine gastropod abalone (Haliotis spp.) is also known to contain a ZP domain protein, raising the possibility of a common molecular basis of metazoan egg coat structures. Egg coat proteins from vertebrate as well as invertebrate taxa have been shown to evolve under positive selection. Studied most extensively in the abalone system, coevolution between adaptively diverging egg coat and sperm proteins may contribute to the rapid development of reproductive isolation. Thus identifying the pattern of evolution among egg coat proteins is important in understanding the role these genes may play in the speciation process. The purpose of the present study is to characterize the constituent proteins of the egg coat (vitelline envelope, VE) of abalone eggs, and to provide preliminary evidence regarding how selection has acted on VE proteins during abalone evolution. We use a proteomic approach to match tandem mass spectra of peptides from purified VE proteins with abalone ovary EST sequences, and identify 9 of 10 novel ZP domain proteins as components of the VE. Maximum likelihood models of codon evolution suggest positive selection has acted among a subset of amino acids for 6 of these genes. This work provides further evidence of the prominence of ZP proteins as constituents of the egg coat, as well as the prominent role of positive selection in diversification of these reproductive proteins.