Identification and Functional Characterization of a Smad Binding Element (SBE) in the JunB Promoter That Acts as a Transforming Growth Factor-β, Activin, and Bone Morphogenetic Protein-inducible Enhancer

• DOI: 10.1074/jbc.273.33.21145
• Publication Date: 2002-07-26T15:11:54Z
• Authors: Luigi J.C. Jonk; Susumu Itoh; Carl-Henrik Heldin; Peter ten Dijke; Wiebe Kruijer
• Keywords: JUNB

Smad proteins have been identified as mediators of intracellular signal transduction by members the transforming growth factor-β (TGF-β) superfamily, which affect cell proliferation, differentiation, well pattern formation during early vertebrate development. Following receptor activation, Smads are assembled into heteromeric complexes consisting a pathway-restricted and common Smad4 that subsequently translocated nucleus where they thought to play an important role in gene transcription. Here we report identification Binding Elements (SBEs) composed sequence CAGACA promoter the<i>JunB</i> gene, immediate is potently induced TGF-β, activin, bone morphogenetic protein (BMP) 2. Two<i>JunB</i> SBEs arranged inverted repeat transactivated response Smad3 co-overexpression shows inducible binding Smad3- Smad4-containing complex nuclear extracts from TGF-β-treated cells. Bacterial-expressed bind directly SBE. Multimerization SBE creates powerful TGF-β-inducible enhancer also responsive activin BMPs. The direct site for will facilitate regulatory elements genes activated TGF-β superfamily.