Bioinformatics Research Center, North Carolina State University, Raleigh, NC, USA.
Department of Statistics, North Carolina State University, Raleigh, NC, USA.
Mol Biol Evol. 2023 Sep 1;40(9). doi: 10.1093/molbev/msad198.
Following a duplication, the resulting paralogs tend to diverge. While mutation and natural selection can accelerate this process, they can also slow it. Here, we quantify the paralog homogenization that is caused by point mutations and interlocus gene conversion (IGC). Among 164 duplicated teleost genes, the median percentage of postduplication codon substitutions that arise from IGC rather than point mutation is estimated to be between 7% and 8%. By differentiating between the nonsynonymous codon substitutions that homogenize the protein sequences of paralogs and the nonhomogenizing nonsynonymous substitutions, we estimate the homogenizing nonsynonymous rates to be higher for 163 of the 164 teleost data sets as well as for all 14 data sets of duplicated yeast ribosomal protein-coding genes that we consider. For all 14 yeast data sets, the estimated homogenizing nonsynonymous rates exceed the synonymous rates.
在发生复制后，产生的直系同源物往往会发生分歧。虽然突变和自然选择可以加速这个过程，但也可以减缓这个过程。在这里，我们量化了由点突变和基因间基因转换（IGC）引起的直系同源物同质化。在 164 个重复的硬骨鱼类基因中，估计由 IGC 而不是点突变引起的复制后密码子取代的中位数百分比在 7%到 8%之间。通过区分使直系同源物的蛋白质序列同质化的非同义密码子取代和非同质化的非同义取代，我们估计在 164 个硬骨鱼类数据集以及我们考虑的所有 14 个重复酵母核糖体蛋白编码基因数据集中，163 个数据集的同质化非同义率更高。对于所有 14 个酵母数据集，估计的同质化非同义率超过同义率。
