title: Interplay between positive and negative elongation factors: drawing a new view of DRB.
abstract: DRB is a classic inhibitor of transcription by RNA polymerase II (pol II). Although it has been demonstrated that DRB inhibits the elongation step of transcription, its mode of action has been elusive. DRB also markedly inhibits human immunodeficiency virus (HIV) transcription, by targeting the elongation which is enhanced by the HIV-encoded transactivator Tat. Two factors essential for DRB action have recently been identified. These factors, positive transcription elongation factor b (P-TEFb) and DRB sensitivity-inducing factor (DSIF), positively and negatively regulate pol II elongation, and are likely to be relevant to the function of Tat. In this review, we summarize the recent findings on these factors, and discuss a possible model for the molecular mechanism of DRB action.
authors.affiliation: Department of Biomolecular Engineering, Faculty of Bioscience and Biotechnology, Tokyo Institute of Technology, Yokohama, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Yamaguchi
authors.forename: T
authors.initials: T
authors.lastname: Wada
authors.forename: H
authors.initials: H
authors.lastname: Handa
mesh_terms: D004004:Dichlororibofuranosylbenzimidazole / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005656:Fungal Proteins / Q000502:physiology; D005786:Gene Expression Regulation / Q000235:genetics; D015756:Genes, tat / Q000235:genetics; D006678:HIV / Q000235:genetics; D006801:Humans; D009687:Nuclear Proteins / Q000502:physiology; D042925:Positive Transcriptional Elongation Factor B; D017346:Protein Serine-Threonine Kinases / Q000502:physiology; D012319:RNA Polymerase II / Q000037:antagonists & inhibitors* / Q000737:chemistry; D012441:Saccharomyces cerevisiae / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology; D014158:Transcription, Genetic / Q000235:genetics*
chemical_list: D004791:Enzyme Inhibitors; D005656:Fungal Proteins; D009687:Nuclear Proteins; D014157:Transcription Factors; D004004:Dichlororibofuranosylbenzimidazole; D042925:Positive Transcriptional Elongation Factor B; D017346:Protein Serine-Threonine Kinases; D012319:RNA Polymerase II