title: Retinoblastoma-binding protein 2 (Rbp2) potentiates nuclear hormone receptor-mediated transcription.
abstract: Retinoblastoma-binding protein 2 (Rbp2) was originally identified as a retinoblastoma protein (RB) pocket domain-binding protein. Although Rbp2 has been shown to interact with RB, p107, TATA-binding protein, and T-cell oncogene rhombotin-2, the physiological function of Rbp2 remains unclear. Here we demonstrate that Rbp2 not only binds to nuclear receptors (NRs) but also enhances the transcription mediated by them. Rbp2 interacts with the DNA-binding domains of NRs and potentiates NR-mediated transcription in an AF-2-dependent manner. Both the N-terminal and C-terminal domains of Rbp2 are critical for the transactivation activity of Rbp2 on NRs. The C terminus is the NR-interacting region. In addition, RB functions in maximizing the effect of Rbp2 on the transcription by NRs. These results suggest that Rbp2 is a coregulator of NRs and define a potential role for Rbp2 in NR-mediated transcription.
authors.affiliation: Institute of Molecular and Cell Biology, 30 Medical Drive, Singapore 117609, Republic of Singapore.
authors.forename: S W
authors.initials: SW
authors.lastname: Chan
authors.forename: W
authors.initials: W
authors.lastname: Hong
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D002352:Carrier Proteins / Q000378:metabolism / Q000502:physiology*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism*; D004591:Electrophoresis, Polyacrylamide Gel; D017930:Genes, Reporter; D005982:Glutathione Transferase / Q000737:chemistry / Q000378:metabolism; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D010957:Plasmids / Q000378:metabolism; D011233:Precipitin Tests; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D018160:Receptors, Cytoplasmic and Nuclear / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D056485:Retinoblastoma-Binding Protein 2; D014158:Transcription, Genetic; D015533:Transcriptional Activation; D014162:Transfection; D025521:Tumor Suppressor Proteins
chemical_list: D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D025521:Tumor Suppressor Proteins; D008156:Luciferases; C070050:KDM5A protein, human; D056485:Retinoblastoma-Binding Protein 2; D005982:Glutathione Transferase