Gene and genome duplications in vertebrates: the one-to-four (-to-eight in fish) rule and the evolution of novel gene functions
Gene and genome duplications in vertebrates: the one-to-four (-to-eight in fish) rule and the evolution of novel gene functions
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DOI：
10.1016/s0955-0674(99)00039-3
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发表时间：
1999-12-01
影响因子：
7.5
通讯作者：
Schartl, M
中科院分区：
文献类型：
--
作者：
Meyer, A;Schartl, M
进化过程中功能创新的一项重要机制是基因和整个基因组的复制。越来越多的证据表明，在脊椎动物从早期后口动物祖先进化而来的过程中，整个基因组通过两轮复制（“一比二比四”规则）进行了复制。脊索动物进化中的第一次基因组复制可能早于寒武纪大爆发。第二次基因组复制可能可以追溯到泥盆纪早期。最近的数据表明，在泥盆纪后期，鱼类基因组被第三次复制，产生了原始后口动物基因组的多达八个副本。最后一次复制发生在有颌脊椎动物的两个主要辐射源——射线鳍鱼（Actinopterygia）和肉鳍鱼谱系——分道扬镳之后。因此，肉鳍鱼，包括腔棘鱼、肺鱼和所有陆地脊椎动物，如两栖动物、爬行动物、鸟类和哺乳动物，其基因数量往往只有放线鱼的一半。尽管许多重复的基因变成了假基因，甚至是“垃圾”DNA，但许多其他基因却进化出了新的功能，特别是在发育过程中。鱼类遗传复杂性的增加可能反映了它们进化的成功和多样性。
One important mechanism for functional innovation during evolution is the duplication of genes and entire genomes. Evidence is accumulating that during the evolution of vertebrates from early deuterostome ancestors entire genomes were duplicated through two rounds of duplications (the one-to-two-to-four' rule). The first genome duplication in chordate evolution might predate the Cambrian explosion. The second genome duplication possibly dates back to the early Devonian. Recent data suggest that later in the Devonian, the fish genome was duplicated for a third time to produce up to eight copies of the original deuterostome genome. This last duplication took place after the two major radiations of jawed vertebrate life, the ray-finned fish (Actinopterygia) and the sarcopterygian lineage, diverged. Therefore the sarcopterygian fish, which includes the coelacanth, lungfish and all land vertebrates such as amphibians, reptiles, birds and mammals, tend to have only half the number of genes compared with actinopterygian fish. Although many duplicated genes turned into pseudogenes, or even 'junk' DNA, many others evolved new functions particularly during development. The increased genetic complexity of fish might reflect their evolutionary success and diversity.