Roles of diversifying selection and coordinated evolution in the evolution of amphibian antimicrobial peptides
Roles of diversifying selection and coordinated evolution in the evolution of amphibian antimicrobial peptides
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DOI：
10.1093/oxfordjournals.molbev.a004143
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发表时间：
2002-06-01
影响因子：
10.7
通讯作者：
Nicolas, P
中科院分区：
文献类型：
--
作者：
Duda, TF;Vanhoye, D;Nicolas, P
抗菌肽在两栖动物的皮肤中表达，用于预防微生物感染。青蛙物种储存了不同的抗菌肽，这些肽的大小各不相同。收费。构象、杀菌活性等抗菌肽基因家族的进化可能反映了这些位点的适应性多样化。我们研究了青蛙和兰尼德蛙物种抗菌肽转录物的分子进化。我们的结果表明，该基因家族在Hylidae和Ranidae的共同祖先中出现之后，在这些家族在中生代分化之前。随后，它在这些群体中多样化，出现大量重复事件和基因座分歧。此外，我们提供的证据表明，抗菌肽基因家族的成员在 hyids 的原片段和成熟结构域内以及仅在 ranids 的成熟结构域内都经历了多样化和选择。最后，我们的结果表明协调和补偿性氨基酸置换发生在 hylid 抗菌肽前体的酸性原片段和阳离子成熟结构域内。正如在哺乳动物防御素基因中所观察到的那样，但在兰尼德前体的防御素基因中却没有观察到。
Antimicrobial peptides are expressed in the skin of amphibian,, and are used to prevent infection by microorganisms. Frog species store distinct collections of antimicrobial peptides that show variation in size. charge. conformation, and bactericidal activity, and so the evolution of antimicrobial peptide gene families may reflect the adaptive diversification of these loci. We examined the molecular evolution of antimicrobial peptide transcripts front hylid and ranid frog species. Our results show that after the gene family arose in file common ancestor of the Hylidae and Ranidae, before the divergence of these families in the Mesozoic. it Subsequently diversified within these groups, with numerous duplication events and divergence of loci. Moreover, we provide evidence that suggests that member.,, of the antimicrobial peptide gene family have been subject to diversifying, selection, within both propiece and mature domains of hylids and solely within the mature domain of ranids, Finally, our results suggest that coordinated and compensatory amino acid replacements hake occurred within the acidic propiece and cationic mature domain of hylid antimicrobial peptide precursors. as has been observed for mammalian defensin genes, but not among those of ranid precursors.