五种裂腹鱼亚科鱼类外胚层发育不良因子A受体基因Edar的克隆和序列分析

Cloning and Sequence Analysis of Ectodysplasin-A Receptor Gene Edar in Five Schizothoracine Fishes

裂腹鱼亚科鱼类具有丰富的体表附属器官变异,而Edar是控制这类结构发育的关键基因。以5种裂腹鱼的代表物种为材料克隆其Edar基因的编码区片段,序列分析表明:该基因编码的蛋白在裂腹鱼中存在长度不同的组氨酸重复序列,串联组氨酸插入可能与蛋白定位有关;基因树支持裂腹鱼与金线鲃具有最近的亲缘关系;分子进化分析未检测到正选择信号,裂腹鱼Edar基因的低复杂区可能是受选择区域。以上结果说明裂腹鱼Edar基因的结构变异可能与裂腹鱼表型变异和演化有关。

Schizothoracine subfamily fishes are rich in variations of skin appendages. The Edar gene plays a vital role in the development of these structures. The coding region segments of Edar gene were obtained from five representative Schizothoracine species. Histidine repeats of different lengths were found in the protein sequences of this gene in Schizothoracine. Tandem histidine inserts might account for the localization of the protein. The gene tree showed that Schizothoracine fishes clustered with the golden-line fish. Signals of positive selection were not detected in our molecular evolution analysis, while the low complextity region of this gene might be the target for selection. It is concluded from the above results that the structural mutations in Schizothoracine Edar gene might be related to the phenotypic variation and evolution in these species.