Evolution of codon usage bias in Drosophila
Evolution of codon usage bias in Drosophila
复制标题
DOI：
10.1073/pnas.94.15.7784
复制
发表时间：
1997-07-22
影响因子：
11.1
通讯作者：
Moriyama, EN
中科院分区：
文献类型：
--
作者：
Powell, JR;Moriyama, EN
我们首先回顾了果蝇密码子使用偏好的已知模式，并提出以下几点：(我)果蝇基因偏见或更多的偏见比微生物,(ii)领带级别佛罗里达大学基因偏见甚至密码子偏向的特定模式可以保持很长时间的进化系统不变,(3)然而,一些男士,甚至基因紧密相连,可以在密码子偏向跨物种变化很大,(iv)通常G特别是C青睐al的网站有偏见的基因,(v)除了天冬氨酸,所有氨基酸对基因密码子使用偏差的贡献都相当显著，（vi）虽然大多数可以在同义位点上使用G或C的氨基酸都显示出对C的偏好，但也有例外：缬氨酸和亮氨酸，它们更倾向于G。（vii）最后，较小的基因往往比较长的基因更偏向于G。我们然后在三个基础上检查这些模式和折扣突变偏差的可能原因：几乎没有证据表明果蝇存在区域突变偏倚，突变偏倚可能倾向于A+T（与密码子使用偏倚相反），并不是所有氨基酸都倾向于在webble位置上的相同核苷酸。两种证据支持基于tRNA傻瓜的选择假设：高度偏倚的基因倾向于高表达和/或快速表达，高度偏倚基因中的首选密码子最佳地结合must。丰富的同工接受trna。最后，我们研究了偏倚对DNA进化的影响，并证实具有高密码子使用偏倚的基因比具有低密码子使用偏倚的基因具有更低的种间同义替换率，令人惊讶的是，我们发现具有较高cc，don使用偏倚的基因表现出更高水平的种内同义多态性，这可能是由于重组的相反作用。
We first review what is known about patterns of codon usage bias in Drosophila and make the following points: (i) Drosophila genes are as biased or more biased than those in microorganisms, (ii) Tie level uf bias of genes and even the particular pattern of codon bias can remain phylogenetically invariant for very long periods of evolution, (iii) However, some gents, even very tightly linked genes, can change very greatly in codon bias across species, (iv) Generally G and especially C are favored al synonymous sites in biased genes, (v) With the exception of aspartic acid, ail amino acids contribute significantly and about equally to the codon usage bias of a gene, (vi) While most individual amino acids that can use G or C at synonymous sites display a preference for C, there are exceptions: valine and leucine, which prefer G. (vii) Finally, smaller genes tend to be more biased titan longer genes, We then examine possible causes of these patterns and discount mutation bias on three bases: there is little evidence of regional mutation bias in Drosophila, mutation bias is likely toward A+T (the opposite of codon usage bias), and not all amino acids display the preference for the same nucleotide in the webble position, Two lines of evidence support a selection hypothesis based on tRNA Fools: highly biased genes lend to be highly and/or rapidly expressed, and the preferred codons in highly biased genes optimally bind the must. abundant isoaccepting tRNAs. Finally, we examine the effect of bias on DNA evolution and confirm that genes with high codon usage bias have lower rates of synonymous substitution between species than do gents with low codon usage bias, Surprisingly, we find that genes with higher cc,don usage bias display higher levels of intraspecific synonymous polymorphism, This may be due to opposing effects of recombination.