Binding of an interferon-inducible protein (p202) to the retinoblastoma protein.
Many of the antimicrobial, immunomodulatory, and cell growth regulatory activities of the interferons are mediated by interferon-inducible proteins. One family of such murine proteins is encoded by six or more adjacent and structurally related genes (gene 200 cluster). Two homologous human genes have also been reported. p202, encoded by the Ifi202 gene in the gene 200 cluster, is a 52-kDa nuclear phosphoprotein. Constitutive overexpression of p202 in transfected cells is growth-inhibitory. We report here that p202 binds the cell growth regulatory retinoblastoma protein (pRb) in vitro and in vivo. The binding is due to direct interaction between the two proteins. p202 has two nonoverlapping segments for binding pRb, and pRb has two nonoverlapping segments (one of them including the pocket region) for binding p202. The hypophosphorylated form of pRb binds to p202, p202 is the first interferon-inducible protein found to bind pRb.
Choubey
D
D
Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut 06520.
Lengyel
P
P
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D015153:Blotting, Western; D002352:Carrier Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D002460:Cell Line; D002467:Cell Nucleus / Q000378:metabolism; D002846:Chromatography, Affinity; D002999:Clone Cells; D016384:Consensus Sequence; D004622:Embryo, Mammalian; D005982:Glutathione Transferase / Q000096:biosynthesis / Q000302:isolation & purification; D006367:HeLa Cells; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins; D051379:Mice; D008806:Mice, Inbred AKR; D008969:Molecular Sequence Data; D005810:Multigene Family; D012516:Osteosarcoma; D010750:Phosphoproteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism*; D014176:Protein Biosynthesis; D011993:Recombinant Fusion Proteins / Q000096:biosynthesis / Q000302:isolation & purification / Q000378:metabolism; D016160:Retinoblastoma Protein / Q000737:chemistry / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D014158:Transcription, Genetic; D014162:Transfection; D014407:Tumor Cells, Cultured; D000071857:Tumor Suppressor p53-Binding Protein 1; D001749:Urinary Bladder Neoplasms
D002352:Carrier Proteins; C092537:Ifi202b protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D010750:Phosphoproteins; D011993:Recombinant Fusion Proteins; D016160:Retinoblastoma Protein; C498301:TP53BP1 protein, human; D000071857:Tumor Suppressor p53-Binding Protein 1; D005982:Glutathione Transferase