Dynamic evolution of the GnRH receptor gene family in vertebrates.
Dynamic evolution of the GnRH receptor gene family in vertebrates.
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DOI：
10.1186/s12862-014-0215-y
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发表时间：
2014-10-25
影响因子：
3.4
通讯作者：
Eisthen HL
中科院分区：
文献类型：
--
作者：
Williams BL;Akazome Y;Oka Y;Eisthen HL
阐明配体和受体共同进化的机制是分子进化生物学的一个重要挑战。考虑到检查编码这两种分子的基因的进化变化相对容易，肽激素及其受体是此类努力的优秀模型。大多数脊椎动物拥有十肽促性腺激素释放激素 (GnRH) 和 GnRH 受体的多个基因。受体家族的进化史，包括祖先拷贝数以及重复和缺失的时间，一直是争议的主题。我们在这里首次报道了蝾螈（蝾螈、Ambystoma mexicanum）中三种不同 GnRH 受体基因的序列，它们与来自蛙类的三种 GnRH 受体是直系同源的。为了在基因家族更大的进化背景下了解这些基因的起源，我们对脊椎动物及其近亲中的 GnRH 受体基因进行了系统发育分析和概率蛋白质同源性搜索。我们的分析揭示了四点，改变了之前关于 GnRH 受体基因家族进化的观点。首先，“哺乳动物”垂体型 GnRH 受体是人类唯一的 GnRH 受体，之前被认为是高度衍生的，因为它缺乏大多数 G 蛋白偶联受体典型的细胞质 C 端结构域，实际上是一个古老的基因，起源于有颌脊椎动物（颌口动物）的共同祖先。其次，与之前的研究不同，我们将脊椎动物 GnRH 受体分为五个亚科。第三，亚科起源的顺序与之前提出的模型相反。第四，GnRH 受体基因的数量在脊椎动物及其祖先中是动态的，存在多次重复和丢失。我们的结果提供了一个新的进化框架，用于生成有关脊椎动物 GnRH 受体结构特征的功能重要性的假设。我们发现脊椎动物 GnRH 受体的五个亚科在脊椎动物系统发育的早期就进化了，随后出现了几个独立的基因丢失实例。基因丢失的主要原因是人类，最好的描述是 GnRH 受体退化，因为我们只保留了一个古老的基因。本文的在线版本 (doi:10.1186/s12862-014-0215-y) 包含补充材料，可供授权用户使用。
Elucidating the mechanisms underlying coevolution of ligands and receptors is an important challenge in molecular evolutionary biology. Peptide hormones and their receptors are excellent models for such efforts, given the relative ease of examining evolutionary changes in genes encoding for both molecules. Most vertebrates possess multiple genes for both the decapeptide gonadotropin releasing hormone (GnRH) and for the GnRH receptor. The evolutionary history of the receptor family, including ancestral copy number and timing of duplications and deletions, has been the subject of controversy. We report here for the first time sequences of three distinct GnRH receptor genes in salamanders (axolotls, Ambystoma mexicanum), which are orthologous to three GnRH receptors from ranid frogs. To understand the origin of these genes within the larger evolutionary context of the gene family, we performed phylogenetic analyses and probabilistic protein homology searches of GnRH receptor genes in vertebrates and their near relatives. Our analyses revealed four points that alter previous views about the evolution of the GnRH receptor gene family. First, the “mammalian” pituitary type GnRH receptor, which is the sole GnRH receptor in humans and previously presumed to be highly derived because it lacks the cytoplasmic C-terminal domain typical of most G-protein coupled receptors, is actually an ancient gene that originated in the common ancestor of jawed vertebrates (Gnathostomata). Second, unlike previous studies, we classify vertebrate GnRH receptors into five subfamilies. Third, the order of subfamily origins is the inverse of previous proposed models. Fourth, the number of GnRH receptor genes has been dynamic in vertebrates and their ancestors, with multiple duplications and losses. Our results provide a novel evolutionary framework for generating hypotheses concerning the functional importance of structural characteristics of vertebrate GnRH receptors. We show that five subfamilies of vertebrate GnRH receptors evolved early in the vertebrate phylogeny, followed by several independent instances of gene loss. Chief among cases of gene loss are humans, best described as degenerate with respect to GnRH receptors because we retain only a single, ancient gene. The online version of this article (doi:10.1186/s12862-014-0215-y) contains supplementary material, which is available to authorized users.
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影响因子：
10.7
作者：
Kumar, Sudhir;Filipski, Alan J.;Tamura, Koichiro
通讯作者：
Tamura, Koichiro
影响因子：
4.8
作者：
Hislop, JN;Everest, HM;McArdle, CA
通讯作者：
McArdle, CA
影响因子：
1
作者：
Kochman, K.
通讯作者：
Kochman, K.
影响因子：
4.8
作者：
Hislop, JN;Madziva, MT;McArdle, CA
通讯作者：
McArdle, CA
影响因子：
3.4
作者：
Lagman D;Ocampo Daza D;Widmark J;Abalo XM;Sundström G;Larhammar D
通讯作者：
Larhammar D