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:12
页码:4874-4878
DOI:10.1073/pnas.87.12.4874
语种:English
出版社:The National Academy of Sciences of the United States of America
摘要:Transcription of human immunodeficiency virus type 1 (HIV-1) is regulated by cis-acting DNA elements located in the viral long terminal repeats, by viral transregulatory proteins, and by cellular transcription factors acting in concert to modulate the degree of viral expression. We demonstrate that a DNA fragment corresponding to the central portion of the HIV-1 genome exhibits enhancer activity when cloned upstream of the thymidine kinase promoter of herpes simplex virus. This enhancer is inducible by phorbol 12-myristate 13-acetate in HeLa cells and is independent of its position and orientation with respect to the promoter. We have mapped the activity of the enhancer to two independent domains encompassing nucleotides 4079-4342 (end of the pol gene) and nucleotides 4781-6026 (vif gene and first coding exon of tat). This intragenic enhancer and its subdomains demonstrate cellular specificity because they are only active in specific cell lines. The presence of similar intragenic enhancer elements in other retroviruses suggests that they might be a conserved feature of this family of viruses.