The cytochrome P450 genesis locus: the origin and evolution of animal cytochrome P450s
The cytochrome P450 genesis locus: the origin and evolution of animal cytochrome P450s
复制标题
DOI：
10.1098/rstb.2012.0474
复制
发表时间：
2013-02-19
影响因子：
6.3
通讯作者：
Stegeman, John J.
中科院分区：
文献类型：
--
作者：
Nelson, David R.;Goldstone, Jared V.;Stegeman, John J.
细胞色素P450（CYP450）基因在后口动物基因组、刺胞动物Nematostella vectensis和鹿角珊瑚Acropora digitifera以及板形动物Trichoplax adhaerens中的邻近区域进行了研究，以寻找有关CYP450基因在动物中进化的线索。在脊索动物中，由2R全基因组复制产生的p53基因已经被鉴定。微同线性和大同线性都被用来鉴定在动物祖先中共存于基因组附近的基因。我们发现，所有11个家族都是在一个共同的基因环境中开始的。这些证据表明存在一个单一的基因座，我们称之为“细胞色素P450基因座”，其中一个祖细胞P450基因复制，以创建一个串联的基因组，这些基因是11个动物P450家族的前体：P450家族2，3，4，7，19，20，26，46，51，74和线粒体。在刺胞动物起源之前，这些早期的基因就已经存在了，可能还夹杂着一些额外的基因。Hox基因簇、WNT基因、NK基因簇和至少一个ARF基因与这个原始的Hox基因座是近邻。根据这一进化情景，CYP 74家族起源于动物，而不是陆地植物，也不是植物和动物的共同祖先。CYP7和CYP19家族是脊索动物特异性的，属于似乎也起源于脊索动物发生位点的哺乳动物家族，尽管这需要许多基因丢失来解释它们目前的分布。揭示基因座的方法克服了由于基因转换，序列分歧，基因出生和死亡造成的混淆效应，并开辟了理解基因，家族和亚科的生物多样性的道路，这些基因在动物中已经被超过6亿年的进化所掩盖。
The neighbourhoods of cytochrome P450 (CYP) genes in deuterostome genomes, as well as those of the cnidarians Nematostella vectensis and Acropora digitifera and the placozoan Trichoplax adhaerens were examined to find clues concerning the evolution of CYP genes in animals. CYP genes created by the 2R whole genome duplications in chordates have been identified. Both microsynteny and macrosynteny were used to identify genes that coexisted near CYP genes in the animal ancestor. We show that all 11 CYP clans began in a common gene environment. The evidence implies the existence of a single locus, which we term the 'cytochrome P450 genesis locus', where one progenitor CYP gene duplicated to create a tandem set of genes that were precursors of the 11 animal CYP clans: CYP Clans 2, 3, 4, 7, 19, 20, 26, 46, 51, 74 and mitochondrial. These early CYP genes existed side by side before the origin of cnidarians, possibly with a few additional genes interspersed. The Hox gene cluster, WNT genes, an NK gene cluster and at least one ARF gene were close neighbours to this original CYP locus. According to this evolutionary scenario, the CYP74 clan originated from animals and not from land plants nor from a common ancestor of plants and animals. The CYP7 and CYP19 families that are chordate-specific belong to CYP clans that seem to have originated in the CYP genesis locus as well, even though this requires many gene losses to explain their current distribution. The approach to uncovering the CYP genesis locus overcomes confounding effects because of gene conversion, sequence divergence, gene birth and death, and opens the way to understanding the biodiversity of CYP genes, families and subfamilies, which in animals has been obscured by more than 600 Myr of evolution.