Ecological adaptation determines functional mammalian olfactory subgenomes
Ecological adaptation determines functional mammalian olfactory subgenomes
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DOI：
10.1101/gr.099416.109
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发表时间：
2010-01-01
期刊：
影响因子：
7
通讯作者：
Teeling, Emma C.
中科院分区：
文献类型：
--
作者：
Hayden, Sara;Bekaert, Michael;Teeling, Emma C.
嗅觉的能力是由哺乳动物基因组中最大的基因家族，嗅觉受体（OR）基因控制的。尽管这些基因在人类和小鼠的基因组中得到了很好的注释，但我们仍然不知道哪些受体与特定的气味物质结合，或者它们是如何发挥作用的。以前的比较研究在分类学上是有限的，主要集中在物种内的OR假基因的百分比。没有研究调查的适应性变化的功能OR基因家族在哺乳动物的遗传和生态多样性。为了确定OR基因库在多大程度上受到栖息地、感觉特化和其他生态特征的影响，为了更好地理解特定OR基因家族的功能重要性以及它们所结合的气味，我们比较了来自50个哺乳动物基因组的功能OR基因库。我们扩增了水生、半水生和飞行哺乳动物中的2000多个OR基因，并将这些数据与从基因组项目中提取的48，000个主要来自陆地哺乳动物的OR基因相结合。系统基因组，贝叶斯分配，和主成分分析分区物种的生态型（水生，半水生，陆生，飞行），而不是系统发育相关性，并确定或家庭重要的每个栖息地。功能性OR基因库在水生哺乳动物的多个起源中独立减少，在蝙蝠中显着不同。我们拒绝最近的嗅觉亚基因组进化的中性观点，并将特定的OR基因家族与生理要求相关联，这是解开特定气味与相应OR基因家族之间关系的初步步骤。
The ability to smell is governed by the largest gene family in mammalian genomes, the olfactory receptor (OR) genes. Although these genes are well annotated in the finished human and mouse genomes, we still do not understand which receptors bind specific odorants or how they fully function. Previous comparative studies have been taxonomically limited and mostly focused on the percentage of OR pseudogenes within species. No study has investigated the adaptive changes of functional OR gene families across phylogenetically and ecologically diverse mammals. To determine the extent to which OR gene repertoires have been influenced by habitat, sensory specialization, and other ecological traits, to better understand the functional importance of specific OR gene families and thus the odorants they bind, we compared the functional OR gene repertoires from 50 mammalian genomes. We amplified more than 2000 OR genes in aquatic, semi-aquatic, and flying mammals and coupled these data with 48,000 OR genes from mostly terrestrial mammals, extracted from genomic projects. Phylogenomic, Bayesian assignment, and principle component analyses partitioned species by ecotype (aquatic, semi-aquatic, terrestrial, flying) rather than phylogenetic relatedness, and identified OR families important for each habitat. Functional OR gene repertoires were reduced independently in the multiple origins of aquatic mammals and were significantly divergent in bats. We reject recent neutralist views of olfactory subgenome evolution and correlate specific OR gene families with physiological requirements, a preliminary step toward unraveling the relationship between specific odors and respective OR gene families.