Dean E Jedediah, Davis Jerel C, Davis Ronald W, Petrov Dmitri A
Stanford Genome Technology Center, Department of Biochemistry, Stanford University, Stanford, California, United States of America.
PLoS Genet. 2008 Jul 4;4(7):e1000113. doi: 10.1371/journal.pgen.1000113.
The loss of functional redundancy is the key process in the evolution of duplicated genes. Here we systematically assess the extent of functional redundancy among a large set of duplicated genes in Saccharomyces cerevisiae. We quantify growth rate in rich medium for a large number of S. cerevisiae strains that carry single and double deletions of duplicated and singleton genes. We demonstrate that duplicated genes can maintain substantial redundancy for extensive periods of time following duplication ( approximately 100 million years). We find high levels of redundancy among genes duplicated both via the whole genome duplication and via smaller scale duplications. Further, we see no evidence that two duplicated genes together contribute to fitness in rich medium substantially beyond that of their ancestral progenitor gene. We argue that duplicate genes do not often evolve to behave like singleton genes even after very long periods of time.
功能冗余的丧失是重复基因进化的关键过程。在此，我们系统地评估了酿酒酵母中大量重复基因间功能冗余的程度。我们对大量携带重复基因和单拷贝基因单缺失及双缺失的酿酒酵母菌株在丰富培养基中的生长速率进行了量化。我们证明，重复基因在复制后很长一段时间（约1亿年）内都能保持相当程度的冗余。我们发现在通过全基因组复制和小规模复制产生的重复基因之间存在高度冗余。此外，我们没有发现证据表明两个重复基因共同对丰富培养基中的适应性做出的贡献显著超过其祖先基因。我们认为，即使经过很长时间，重复基因也不常进化得像单拷贝基因那样。
