Bioinformatics and Molecular Evolution Group, School of Biotechnology, Dublin City University, Glasnevin, Dublin 9, Ireland.
BMC Evol Biol. 2010 Feb 11;10:39. doi: 10.1186/1471-2148-10-39.
Reproductive proteins are central to the continuation of all mammalian species. The evolution of these proteins has been greatly influenced by environmental pressures induced by pathogens, rival sperm, sexual selection and sexual conflict. Positive selection has been demonstrated in many of these proteins with particular focus on primate lineages. However, the mammalia are a diverse group in terms of mating habits, population sizes and germ line generation times. We have examined the selective pressures at work on a number of novel reproductive proteins across a wide variety of mammalia.
We show that selective pressures on reproductive proteins are highly varied. Of the 10 genes analyzed in detail, all contain signatures of positive selection either across specific sites or in specific lineages or a combination of both. Our analysis of SP56 and Col1a1 are entirely novel and the results show positively selected sites present in each gene. Our findings for the Col1a1 gene are suggestive of a link between positive selection and severe disease type. We find evidence in our dataset to suggest that interacting proteins are evolving in symphony: most likely to maintain interacting functionality.
Our in silico analyses show positively selected sites are occurring near catalytically important regions suggesting selective pressure to maximize efficient fertilization. In those cases where a mechanism of protein function is not fully understood, the sites presented here represent ideal candidates for mutational study. This work has highlighted the widespread rate heterogeneity in mutational rates across the mammalia and specifically has shown that the evolution of reproductive proteins is highly varied depending on the species and interacting partners. We have shown that positive selection and disease are closely linked in the Col1a1 gene.
生殖蛋白是所有哺乳动物物种延续的核心。这些蛋白质的进化受到病原体、竞争精子、性选择和性冲突引起的环境压力的极大影响。许多研究都证明了这些蛋白质中存在正选择，尤其是在灵长类动物谱系中。然而，哺乳动物在交配习惯、种群大小和生殖系世代时间等方面存在多样性。我们研究了许多新型生殖蛋白在广泛的哺乳动物中所受到的选择压力。
我们表明，生殖蛋白受到的选择压力高度多样化。在详细分析的 10 个基因中，所有基因都包含正选择的特征，要么是在特定位点，要么是在特定谱系中，要么是两者兼有。我们对 SP56 和 Col1a1 的分析是全新的，结果显示每个基因中都存在正选择的位点。我们对 Col1a1 基因的分析结果表明，正选择与严重疾病类型之间存在关联。我们在数据集内发现了证据，表明相互作用的蛋白质可能以协同的方式进化：最有可能维持相互作用的功能。
我们的计算机分析表明，正选择的位点出现在催化重要区域附近，表明选择压力是为了最大限度地提高受精效率。在那些蛋白质功能机制尚未完全理解的情况下，这里提出的位点是突变研究的理想候选位点。这项工作突出了哺乳动物中突变率的广泛异质性，具体表明生殖蛋白的进化高度依赖于物种和相互作用的伴侣。我们已经表明，在 Col1a1 基因中，正选择和疾病密切相关。
