中国地方株人乳头瘤病毒16型E7基因一级结构及其变异

Primary structure and variation of HPV 16 E7-HB from China

从湖北地区一宫颈癌活检组织中提取ＤＮＡ，采取加端聚合酶链反应（ＰＣＲ）技术，获得了人乳头瘤病毒１６型Ｅ７基因（ＨＰＶ１６Ｅ７）。将该基因克隆于载体ｐＵＣ１８后，进行了该基因一级结构顺序分析。完整的ＨＰＶ１６Ｅ７湖北株基因（ＨＰＶ１６Ｅ７－ＨＢ）全长２９４ｂｐ，与已发表的德国株（ＧＳ）大小一致，但其核苷酸顺序中有２处发生了变异，均为Ｃ→Ｔ变异。

A complete E7 gene of HPV16 was isolated from a cervical carcinoma biopsy DNA from Hubei province of China by Add-on PCR. After cloning into plasmid pUC18 , the total nucleotide sequence of HPVl6 E7 was determined. The entire HPV16 E7 gene has 294 nucleotides. It was the same as the German strain. But there were two mutations in sequences. Both of them were C→T mutation. A nonsense mutation was identified at coden 43,a Gln codon (CAA) was converted into TAA ,the stop codon, A 0. 3kb fragment of HPV16 E7-HB was inserted into experssed vector pWR590-1. When E coli JM 109 was transformed by recombinant expression plasmid and induced by IPTG, a fusion protein product with the expected molecutar weight 69kD was observed , which was approximately 30％ of the total bacterial proteins. It was comfirmed that virus polypeptiedes by E7 encoded stoped in advance because of nonsense mutation of HPVl6 E7-HB. The results showed: there were gene structure and polypeptide difference of HPV16 E7 in different country and/or area. This is the first report of HPV16 E7 primary structure of China.