Human and simian immunodeficiency retroviruses: activation and differential transactivation of gene expression.
New West African human immunodeficiency viruses (HIV-2s) and simian immunodeficiency virus (SIV) contain functional transactivator (tat) gene and tat response elements. Their long terminal repeats (LTR) and tat genes are more related among themselves than to HIV-1 LTR and tat gene. The viral gene expression of HIV-2 as well as SIV can be stimulated by T cell activators, such as mitogens and phorbol esters. HIV-2 and SIV display a much broader transactivation response specificity than does HIV-1. The LTR-directed gene expression of HIV-2/SIV is not only transactivated by their own tat gene and by HIV-1 tat gene but also by factors in human T cell leukemia/lymphoma virus type I (HTLV-I) and simian virus 40 (SV40) infected cells, involving HTLV-I tat gene and SV40 T antigens, respectively. HIV-1 LTR-directed gene expression is much less transactivated by HIV-2/SIV tat genes and by factors in HTLV-I- and SV40-infected cells. Immune activation and heterologous transactivation of the LTR-directed gene expression may be relevant to the latency of virus infection and progression toward the acquired immunodeficiency syndrome (AIDS).
Arya
S K
SK
Laboratory of Tumor Cell Biology, National Cancer Institute, Bethesda, MD 20892.
D000818:Animals; D002460:Cell Line; D005786:Gene Expression Regulation; D005814:Genes, Viral; D000882:Haplorhini; D006801:Humans; D008992:Monkey Diseases / Q000382:microbiology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D012091:Repetitive Sequences, Nucleic Acid; D012190:Retroviridae / Q000235:genetics*; D012192:Retroviridae Infections / Q000662:veterinary*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D010835:Phytohemagglutinins; D013755:Tetradecanoylphorbol Acetate