title: Transcriptional and posttranscriptional regulation of HIV-1 gene expression.
abstract: Control of HIV-1 gene expression depends on two viral regulatory proteins, Tat and Rev. Tat stimulates transcription elongation by directing the cellular transcriptional elongation factor P-TEFb to nascent RNA polymerases. Rev is required for the transport from the nucleus to the cytoplasm of the unspliced and incompletely spliced mRNAs that encode the structural proteins of the virus. Molecular studies of both proteins have revealed how they interact with the cellular machinery to control transcription from the viral LTR and regulate the levels of spliced and unspliced mRNAs. The regulatory feedback mechanisms driven by HIV-1 Tat and Rev ensure that HIV-1 transcription proceeds through distinct phases. In cells that are not fully activated, limiting levels of Tat and Rev act as potent blocks to premature virus production.
authors.affiliation: Department of Molecular Biology and Microbiology, Case Western Reserve University, Cleveland, Ohio 44106, USA. jonathan.karn@case.edu
authors.forename: Jonathan
authors.initials: J
authors.lastname: Karn
authors.forename: C Martin
authors.initials: CM
authors.lastname: Stoltzfus
mesh_terms: D025461:Feedback, Physiological / Q000502:physiology; D015870:Gene Expression / Q000235:genetics*; D016153:Genes, Suppressor / Q000502:physiology; D015658:HIV Infections / Q000821:virology*; D015497:HIV-1 / Q000235:genetics*; D006801:Humans; D026723:Polyadenylation / Q000502:physiology; D012326:RNA Splicing / Q000502:physiology; D012367:RNA, Viral / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic / Q000235:genetics*; D014775:Virus Activation / Q000502:physiology; D014779:Virus Replication / Q000502:physiology; D054321:rev Gene Products, Human Immunodeficiency Virus / Q000235:genetics*; D054322:tat Gene Products, Human Immunodeficiency Virus / Q000235:genetics*
chemical_list: D012367:RNA, Viral; D014157:Transcription Factors; D054321:rev Gene Products, Human Immunodeficiency Virus; D054322:tat Gene Products, Human Immunodeficiency Virus