Recombination between elongation factor 1α genes from distantly related archaeal lineages
Recombination between elongation factor 1α genes from distantly related archaeal lineages
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DOI：
10.1073/pnas.0600744103
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发表时间：
2006-03-21
影响因子：
11.1
通讯作者：
Roger, AJ
中科院分区：
文献类型：
--
作者：
Inagaki, Y;Susko, E;Roger, AJ
同源重组和基因横向转移是基因组进化的主要过程。这两个过程的结合，即不同物种基因之间的HR，已经被记录下来，但被认为仅限于在相对密切相关的生物体中非常相似的序列。在这里，我们报告了两个在远亲古细菌群体中编码核心翻译蛋白翻译延伸因子1 α (EF-1 α)基因的种间HR。最大似然滑动窗口分析表明，来自以Methanopyrus kandleri为代表的古细菌谱系的EF-1 α基因片段在热球菌的共同祖先中重组为同源基因。第二次重组事件似乎发生在Methanothermobacter属的EF-1 α基因与其在Methanosarcinales（一个远亲euryarchaeal谱系）的共同祖先中的同系物之间。这些发现表明，HR发生的进化距离比一般认为的要大得多，并且影响高度保守的基本“信息”基因。尽管很难通过标准的全基因系统发育分析来检测，但高度保守基因的种间HR可能以相当高的频率发生，可能会混淆深层系统发育推断和假设检验。
Homologous recombination (HR) and lateral gene transfer are major processes in genome evolution. The combination of the two processes, HR between genes in different species, has been documented but is thought to be restricted to very similar sequences in relatively closely related organisms. Here we report two cases of interspecific HR in the gene encoding the core translational protein translation elongation factor 1 alpha (EF-1 alpha) between distantly related archaeal groups. Maximum-likelihood sliding window analyses indicate that a fragment of the EF-1 alpha gene from the archaeal lineage represented by Methanopyrus kandleri was recombined into the orthologous gene in a common ancestor of the Thermococcales. A second recombination event appears to have occurred between the EF-1 alpha gene of the genus Methanothermobacter and its ortholog in a common ancestor of the Methanosarcinales, a distantly related euryarchaeal lineage. These findings suggest that HR occurs across a much larger evolutionary distance than generally accepted and affects highly conserved essential "informational" genes. Although difficult to detect by standard whole-gene phylogenetic analyses, interspecific HR in highly conserved genes may occur at an appreciable frequency, potentially confounding deep phylogenetic inference and hypothesis testing.