ISOLATION AND SEQUENCING OF THE EPSTEIN-BARR-VIRUS BNLF-1 GENE (LMP1) FROM A CHINESE NASOPHARYNGEAL CARCINOMA
ISOLATION AND SEQUENCING OF THE EPSTEIN-BARR-VIRUS BNLF-1 GENE (LMP1) FROM A CHINESE NASOPHARYNGEAL CARCINOMA
复制标题
DOI：
10.1099/0022-1317-72-10-2399
复制
发表时间：
1991-10-01
影响因子：
3.8
通讯作者：
WINBERG, G
中科院分区：
文献类型：
--
作者：
HU, LF;ZABAROVSKY, ER;WINBERG, G
从中国人鼻咽癌细胞株CAO的基因组文库中克隆了含有EB病毒LMP 1基因的BamHI片段。测定了LMP 1基因及其启动子和增强子的序列。CAO分离株的核苷酸序列与B 95 -8和Raji分离株的启动子/增强子区域不同;蛋白质的氨基酸序列也不同。蛋白质的结构差异主要位于20个N-末端残基和蛋白质C-末端部分的重复氨基酸阵列，其中CAO分离物显示11个氨基酸（aa）的7个完美重复的簇。其中三个重复序列在其他病毒株中没有对应物。这与C-末端部分的5个和10个氨基酸的两个缺失一起，产生404个氨基酸的蛋白质，而B 95 -8和Raji为386个氨基酸。较大的LMP 1蛋白检测到免疫印迹的组织样品从CAO裸鼠肿瘤，也存在于EBV阴性B细胞系和永生化的角质形成细胞转染的克隆基因。CAO EBV分离株和37例中国人鼻咽癌活检标本中的36例均未发现B 95 -8 BNLF-1基因外显子1的XhoI限制性酶切位点。相比之下，19例非洲来源的NPC活检中有17例保留了这个XhoI位点。
The BamHI fragment containing the Epstein-Barr virus (EBV) LMP1 gene was cloned from a genomic library of the nude mouse-propagated Chinese nasopharyngeal carcinoma CAO. The sequence of the LMP1 gene and its promoter and enhancer was determined. The nucleotide sequence of the CAO isolate differed from those of the B95-8 and Raji isolates in the promoter/enhancer region; the amino acid sequence of the protein also differed. Structural differences in the protein were located mainly in the 20 N-terminal residues and the array of repeated amino acids in the C-terminal part of the protein, in which the CAO isolate displays a cluster of seven perfect repeats of 11 amino acids (aa). Three of these repeats have no counterpart in the other virus strains. This, together with two deletions of five and 10 aa in the C-terminal part, yields a protein of 404 aa, compared to 386 aa for B95-8 and Raji. The larger LMP1 protein was detected on immunoblots of tissue samples from the CAO nude mouse tumour, and was also present in EBV-negative B cell lines and immortalized keratinocytes transfected with the cloned gene. A XhoI restriction site in exon 1 of the B95-8 BNLF-1 gene was absent from the CAO EBV isolate, as well as from 36 of 37 Chinese NPC biopsies tested. In contrast, 17 of 19 NPC biopsies of African origin retained this XhoI site.