Global trends of whole-genome duplications revealed by the ciliate Paramecium tetraurelia
Global trends of whole-genome duplications revealed by the ciliate Paramecium tetraurelia
复制标题
DOI：
10.1038/nature05230
复制
发表时间：
2006-11-09
期刊：
影响因子：
64.8
通讯作者：
Wincker, Patrick
中科院分区：
文献类型：
--
作者：
Aury, Jean-Marc;Jaillon, Olivier;Wincker, Patrick
整个基因组的复制长期以来被认为具有巨大的进化潜力，但通过基因丢失解决其问题的机制却知之甚少。在这里，我们表明，在单细胞真核生物草履虫tetraurelia，纤毛虫，近40,000个基因中的大多数出现通过至少三个连续的全基因组复制。系统发育分析表明，最近的重复与物种形成事件的爆炸相吻合，导致了15个兄弟物种的P.奥雷利亚复合体。我们观察到，基因丢失发生在一个很长的时间尺度上，而不是作为一个初始的大规模事件。来自相同代谢途径或蛋白质复合物的基因具有共同的基因丢失模式，并且高表达基因在所有复制后被过度保留。这个分析的结论是，许多基因在全基因组复制后得以保留，不是因为功能创新，而是因为基因剂量的限制。
The duplication of entire genomes has long been recognized as having great potential for evolutionary novelties, but the mechanisms underlying their resolution through gene loss are poorly understood. Here we show that in the unicellular eukaryote Paramecium tetraurelia, a ciliate, most of the nearly 40,000 genes arose through at least three successive whole-genome duplications. Phylogenetic analysis indicates that the most recent duplication coincides with an explosion of speciation events that gave rise to the P. aurelia complex of 15 sibling species. We observed that gene loss occurs over a long timescale, not as an initial massive event. Genes from the same metabolic pathway or protein complex have common patterns of gene loss, and highly expressed genes are over-retained after all duplications. The conclusion of this analysis is that many genes are maintained after whole-genome duplication not because of functional innovation but because of gene dosage constraints.