牦牛IL-4基因的克隆及其遗传演化关系分析

Cloning and Sequence Analysis of Yak Interleukin-4 gene

克隆牦牛白细胞介素-4（IL～4）基因，并对其进行遗传演化分析。从刀豆素（ConA）和脂多糖（LPS）联合刺激培养的牦牛外周血淋巴细胞提取总RNA．利用RT—PCR方法扩增牦牛IL-4全长cDNA，将其克隆到pMD18～T载体上，测序后进行序列分析。成功克隆到牦牛IL-4基因全序列，序列分析表明，克隆的牦牛IL-4基因序列与GenBank所登录的牛IL-4核苷酸序列及推导的氨基酸序列的同源性分别这99．8％和100％，与人、猕猴、猪、山羊、马等物种的核苷酸及其推导氨基酸序列的同源性分别在44．4％～96．3％和27．4％～91．1％之间。在国内首次成功地从牦牛外周血淋巴细胞中克隆到IL-4的基因，其ORF为408bp，推导编码135个氨基酸。

Cloning and genetic analysis of yak interleukin-4 gene were conducted. The full length cDNA of boiL-4 was amplified by RT-PCR from the yak peripheral blood lymphocyte stimulated by ConA and LPS, and was cloned in pMD18-T vector and sequenced. Homologies of nucleotide and deduced amino acid sequences between the yak IL-4 and registered boiL4 in the GenBank are 99.8% and 100%,respectively. Homologies of yak IL-4 nucleotide sequence compared with Homo, Macaca, Sus scrofa, Capra and Equus are in 44.4%-99.8%. Homologies of amino acid sequence of them are in 27.4%-91.1%. In conclusion, IL- 4 containing an ORF of 408 bp and coding 135 amino acids was first cloned successfully from the yak PBMC in China.