title: The RING domain of PIASy is involved in the suppression of bone morphogenetic protein-signaling pathway.
abstract: Bone morphogenetic proteins (BMPs) play central roles in differentiation, development, and physiologic tissue remodeling. Recently, we have demonstrated that a protein inhibitor of activated STAT, PIASy, suppresses TGF-beta signaling by interacting with Sma and MAD-related protein 3 (Smad3). In this study, we examined a PIASy-dependent inhibitory effect on BMP signaling. PIASy expression was induced by BMP-2 stimulation and suppressed BMP-2-dependent Smad activity in hepatoma cells. Furthermore, BMP-2-regulated Smads directly bound to PIASy. We also demonstrated that the RING domain of PIASy played an important role in PIASy-mediated suppression of Smad activity. We here provide evidence that the inhibitory action of PIASy on BMP-regulated Smad activity was due to direct physical interactions between Smads and PIASy through its RING domain.
authors.affiliation: Department of Immunology, Graduate School of Pharmaceutical Sciences, Hokkaido University, Kita-Ku Kita 12 Nishi 6, Sapporo 060-0812, Japan.
authors.forename: Seiyu
authors.initials: S
authors.lastname: Imoto
authors.forename: Kenji
authors.initials: K
authors.lastname: Sugiyama
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Tadashi
authors.initials: T
authors.lastname: Matsuda
mesh_terms: D015152:Blotting, Northern; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins / Q000737:chemistry* / Q000378:metabolism; D006528:Carcinoma, Hepatocellular / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry*; D002460:Cell Line; D004268:DNA-Binding Proteins / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D015151:Immunoblotting; D047908:Intracellular Signaling Peptides and Proteins; D008156:Luciferases / Q000378:metabolism; D000075223:Poly-ADP-Ribose Binding Proteins; D011233:Precipitin Tests; D011485:Protein Binding; D050828:Protein Inhibitors of Activated STAT; D017434:Protein Structure, Tertiary; D020133:Reverse Transcriptase Polymerase Chain Reaction; D015398:Signal Transduction; D051785:Smad Proteins; D013997:Time Factors; D015534:Trans-Activators / Q000378:metabolism; D014158:Transcription, Genetic; D014162:Transfection; D016212:Transforming Growth Factor beta
chemical_list: C525718:BMP2 protein, human; D055396:Bone Morphogenetic Protein 2; D019485:Bone Morphogenetic Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D047908:Intracellular Signaling Peptides and Proteins; C485891:PIAS4 protein, human; D000075223:Poly-ADP-Ribose Binding Proteins; D050828:Protein Inhibitors of Activated STAT; D051785:Smad Proteins; D015534:Trans-Activators; D016212:Transforming Growth Factor beta; D008156:Luciferases