南阳黄牛CD14基因扩增及序列分析

根据GenBank发表的荷斯坦奶牛CD14基因的序列设计引物,通过PCR方法对南阳黄牛的CD14基因进行分段扩增并测序,拼接后得到包含CD14完整编码区以及5’端和3’端非编码区的2 969 bp的全序列。序列分析结果表明:南阳黄牛CD14基因开放阅读框全长966 bp,共编码321个氨基酸,碱基组成分别为A(18.4%)、T(18.4%)、C(32.9%)、G(30.2%),编码区与荷斯坦奶牛CD14基因相比发生了2个碱基突变,没有引起氨基酸的改变。在5’端和3’端存在较长的非编码区,与荷斯坦奶牛CD14基因相比发生了7个碱基突变。南阳黄牛的CD14基因与荷斯坦奶牛、水牛、绵羊、山羊、猪、猕猴、大猩猩、人、小鼠的同源性依次降低,分别为99.8%、98.2%、96.8%、92.8%、83.5%、79.8%、79.7%、79.5%、71.9%。进化树所得的聚类结果与传统的分类结果一致。通过蛋白质结构预测,发现南阳黄牛CD14没有跨膜结构域。

Amplification and Sequence Analysis of CD14 Gene in Nanyang Yellow Cattle

The CD14 gene in Nanyang yellow cattle was segmently amplificated by polymerase chain reaction(PCR) method.Primers were designesd according to CD14 gene sequence of Holstein in GenBank.The complete sequence of 2 969 bp,containing complete coding region of CD14,5’ and 3’non-coding region,were obtained.Sequence analysis showed that CD14 gene in Nanyang Yellow cattle contains ORF of 966 bp in length encoded 321 amino acids,comprised of A(18.4%),T(18.4%),C(32.9%),G(30.2%).2 bases of coding region were changed compared to CD14 gene of Holstein,but none of amino acid changed.7 bases of non-coding region at the end of 5’ and 3’were changed compared to CD14 gene of Holstein.The homology rates of nucleotide sequences of CD14 gene among Nanyang yellow cattle and Holstein cow,buffalo,sheep,goats,pigs,monkeys,gorillas,human,mouse were decreased in turn,and were 99.8%,98.2%,96.8%,92.8%,83.5%,79.8%,79.7%,79.5%,71.9% respectively.The results of categorize from phylogenetic tree were similar to the traditional classification results.There is no transmembrane domains by means of protein structure prediction of CD14 gene sequence in Nanyang yellow cattle.