Roberts M S, Cohan F M
Department of Biology, Wesleyan University, Middletown, Connecticut 06459-0170.
Genetics. 1993 Jun;134(2):401-8. doi: 10.1093/genetics/134.2.401.
We have investigated the relationship between sexual isolation and DNA sequence divergence in the transformation (at locus rpoB) of a naturally competent strain of Bacillus subtilis. Using both genomic DNA and a PCR-amplified segment of gene rpoB as donor, we found that the extent of sexual isolation at locus rpoB was closely predicted, over three orders of magnitude, as a log-linear function of sequence divergence at that locus. Because sexual isolation between a recipient and any potential donor may be determined as a general mathematical function of sequence divergence, transformation is perhaps the only sexual system, in either the prokaryotic or the eukaryotic world, in which sexual isolation can be predicted for a pair of species without having to perform the cross. These observations suggest the possibility of a general approach to the indirect prediction of sexual isolation in bacteria recombining principally by natural transformation.
我们研究了枯草芽孢杆菌自然感受态菌株在转化过程中(rpoB位点)性隔离与DNA序列差异之间的关系。使用基因组DNA和基因rpoB的PCR扩增片段作为供体,我们发现rpoB位点的性隔离程度在三个数量级上都能作为该位点序列差异的对数线性函数被精确预测。由于受体与任何潜在供体之间的性隔离可以被确定为序列差异的一般数学函数,因此转化可能是原核生物或真核生物世界中唯一一种无需进行杂交就能预测一对物种性隔离的有性系统。这些观察结果表明,对于主要通过自然转化进行重组的细菌,可能存在一种间接预测性隔离的通用方法。