牛Smad4基因cDNA克隆及生物信息学分析

Cloning and Bioinformaton Analysis of cDNA Encoding Cattle Smad4 Gene

Smad4基因在TGF-β细胞内信号传导过程中起重要作用,通过生物信息学方法,结合RT-PCR技术和SMART RACE技术,对牛Smad4基因进行了克隆,得到了3 503 bp cDNA全长序列并向GenBank递交了该序列,登录号:DQ494856。通过核酸序列分析发现,牛Smad4基因由12个外显子组成,编码553个氨基酸。该基因与绵羊、猪、人、大鼠和小鼠在核酸序列上分别有99%、96%、95%、91%、91%的同源性;在氨基酸序列上分别有99%、98%、98%、99%和98%的同源性,牛Smad4基因的组织表达谱很广,在睾丸、胰腺、肝、小肠、卵巢、淋巴结、心肌、骨骼肌、胸腺组织中都有表达。

Cattle Smad4 gene eDNA was cloned by RT-PCR, 3＇RACE and 5＇RACE and got a 3 503bp full-long eDNA sequence. The cloned cattle Smad4 cDNA sequence had been send to GenBank and got a accession number. DQ494856. Cattle Smad4 gene consists of 12 exons and codes 553 amino acids. Cattle Smad4 eDNA shares 99%, 96%, 95%, 91%, 91% similarity in nucleic acid sequences and 99%, 98%, 98%, 99%, 98% similarity in amino acid sequences with sheep, pig, human, rat and mouse respectively. Smad4 cDNA was found in testis, pancreas, liver, small intestine, ovary, lymphnode, cardiac muscle, skeleton muscle and thymus gland, this indicated Smad4 is broad expressed in cattle.