McInerney J O
Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, United Kingdom.
Proc Natl Acad Sci U S A. 1998 Sep 1;95(18):10698-703. doi: 10.1073/pnas.95.18.10698.
With more than 10 fully sequenced, publicly available prokaryotic genomes, it is now becoming possible to gain useful insights into genome evolution. Before the genome era, many evolutionary processes were evaluated from limited data sets and evolutionary models were constructed on the basis of small amounts of evidence. In this paper, I show that genes on the Borrelia burgdorferi genome have two separate, distinct, and significantly different codon usages, depending on whether the gene is transcribed on the leading or lagging strand of replication. Asymmetrical replication is the major source of codon usage variation. Replicational selection is responsible for the higher number of genes on the leading strands, and transcriptional selection appears to be responsible for the enrichment of highly expressed genes on these strands. Replicational-transcriptional selection, therefore, has an influence on the codon usage of a gene. This is a new paradigm of codon selection in prokaryotes.
随着超过10个已完全测序且公开可用的原核生物基因组的出现，现在有可能对基因组进化获得有用的见解。在基因组时代之前，许多进化过程是根据有限的数据集进行评估的，进化模型也是基于少量证据构建的。在本文中，我表明伯氏疏螺旋体基因组上的基因有两种独立、不同且显著不同的密码子使用情况，这取决于该基因是在复制的前导链还是后随链上转录。不对称复制是密码子使用变异的主要来源。复制选择导致前导链上的基因数量更多，而转录选择似乎导致这些链上高表达基因的富集。因此，复制-转录选择对基因的密码子使用有影响。这是原核生物中密码子选择的一种新范式。
