鲤鱼Ectodysplasin-A(Eda)基因生物信息学及功能分析

Bioinformatic and Functional Analysis of Ectodysplasin-A from Common carp(Cyprinus carpio,Cyprinidae)

Ectodysplasin-A(Eda)基因在皮肤附属物的发育中具有重要的生物学功能。利用Genfishing差异筛选技术对普通鲤鱼和德国镜鲤的皮肤转录表达产物进行筛选,得到Eda基因的部分片段。然后利用实验室的鲤鱼EST数据库设计包含CDS全长的特异引物。克隆测序后发现,镜鲤Eda基因全长CDS包含1 062个碱基,编码一个含有354个氨基酸的蛋白质,包含一个受体结合位点序列。序列比对结果表明,鲤鱼Eda蛋白与斑马鱼相似度最高,达92.76%,而与其亲缘关系较远的鸡、人类、老鼠相似度较低,分别是46.61%、50.51%、50.76%。同时对RACE得到的5'-UTR区进行分析表明,该调控区与斑马鱼相比变异不大(相似度92.98%),但是与其亲缘关系较远的物种变异较大(与人类的相似度为23.36%,与老鼠的相似度为31.07%)。原位杂交结果表明,该基因在鲤鱼鳞片发生时在鳞片着生的皮肤基质中特异表达,而在非鳞片发生区域表达较弱或者不表达,而在全部鳞片发育形成后,该基因的表达消失,表明该基因可能参与鲤鱼鳞片的起始发育而不是后期的鳞片模式维持过程。

The Ectodysplasin-A （ Eda ） plays vital roles in developmental events of the skin appendages. The screening of transcripts of skin from common carp and the Germany mirror carp by Genefishing differential display, found Eda is one of the targeted different expressed in both materials, and the partial fragment of Eda gene was recovered from differential expressed products by sequencing. The specific primers contained the full length of Eda were designed with the reference sequence of Eda EST in our Carp database. The mirror carp Eda CDS consisted of 1 062 base pair nucleotides which encodes a 354 amino acid protein, has a receptor-binding region. The alignment result showed that the carp shareed the highest similarity （ 92.76% ） with the zebrafish. However, it had the relative lower similarity with chicken （ 46.61% ） , human （ 50.51% ） , mouse （ 50.76% ） due to evolutionarily distant relationships. The 5＇-UTR regulation region of Eda shared the high similarity with the zebrafish （ 92.98% ） , but varies significantly with human （ only 23.36% ） , mouse （ 31.07% ） . The in situ results showed that the Eda unique expression signal was detected in skin matrix which the scale formed, however weak or no expression signal was detected in other positions on skin, later disappeared in full developed scale body. All of these results showed that this gene may involve the initiation of the scales not the maintainence of the scale pattern formation.