Chen Y, Guo H, Cao H
Department of Microbiology, Sun Yat-sen University of Medical Sciences, Guangzhou, 510089.
Zhonghua Shi Yan He Lin Chuang Bing Du Xue Za Zhi. 1999 Sep 30;13(3):217-21.
To study the variation of EBV LMP1 encoding gene isolated from human nasopharyngeal carcinoma cell line SUNE1 in Guangdong.
The EBV LMP1 gene was amplified from the SUNE1 cell genome by PCR and then the recombinant vector was constructed by inserting the PCR fragment into pcDNA3. The encoding EBV LMP1 spanning from exon1 to exon3 in recombinant vector was sequenced by the Sequence Analyzer.
The 1,312 bp encoding EBV LMP1 pieces in 2.6 kb PCR fragments were compared with the same EBV segments in B95-8 cell line. The data indicated that the rate of nucleotide sequence homology between the two fragments is 98.5% and the rate of amino acid is 96%. The restricted enzyme site of Xho I in exon1 was deleted in SUNE1 but the 30 bp deletion at the carboxyl terminus in most Chinese NPC LMP1 gene was not present.
Although the LMP1 gene derived from SUNE1 had greater tumorigenicity than that derived from B95-8 cell, the high homology rate of nucleotide and amino acid sequences between them indicated that it was not the result from the variation of certain nucleotide sites but the change in amino acid domain.
研究从广东人鼻咽癌SUNE1细胞系中分离出的EBV LMP1编码基因的变异情况。
采用PCR法从SUNE1细胞基因组中扩增EBV LMP1基因，将PCR片段插入pcDNA3构建重组载体，用序列分析仪对重组载体中跨越外显子1至外显子3的EBV LMP1编码区进行测序。
将2.6 kb PCR片段中1312 bp的EBV LMP1编码片段与B95-8细胞系中相同的EBV片段进行比较。数据显示，两个片段的核苷酸序列同源率为98.5%，氨基酸同源率为96%。SUNE1中外显子1的Xho I酶切位点缺失，但不存在大多数中国鼻咽癌LMP1基因羧基末端30 bp的缺失。
虽然源自SUNE1的LMP1基因比源自B95-8细胞的LMP1基因具有更强的致瘤性，但它们之间核苷酸和氨基酸序列的高同源率表明，这并非某些核苷酸位点变异的结果，而是氨基酸结构域的改变所致。
