标题:Epstein-Barr virus-encoded nuclear antigen 2 activates the viral latent membrane protein promoter by modulating the activity of a negative regulatory element.
期刊名称:Proceedings of the National Academy of Sciences
印刷版ISSN:0027-8424
电子版ISSN:1091-6490
出版年度:1990
卷号:87
期号:19
页码:7390-7394
DOI:10.1073/pnas.87.19.7390
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Previous studies suggest that the Epstein-Barr virus nuclear antigen EBNA2 participates in the regulation of the expression of the viral latent membrane protein (LMP). We have used reporter plasmids containing DNA fragments of the 5' flanking region of the LMP gene in cotransfection experiments to analyze the effect of EBNA2 on the activity of the LMP promoter. The results show that the LMP promoter is controlled by positive and negative transcription elements in a DNA fragment that contains the LMP transcription initiation site and 634 base pairs of upstream sequences. The promoter is activated by EBNA2. The region between position -54 and +40 relative to the mRNA cap site contains a positive transcription element that is constitutively active in DG75 cells and independent of EBNA2. The -106 to -54 region contains a negative regulatory element that prevents adjacent positive elements from functioning in the absence of EBNA2. Regulatory sequences between -324 and -144 participate in maintaining a high level of transcription of the LMP promoter after induction with EBNA2. The regulatory elements in the -634 to -54 promoter region have the characteristics of an inducible enhancer, including orientation independence and ability to regulate a heterologous promoter.