Regulation of SMRT corepressor dimerization and composition by MAP kinase phosphorylation.

ABSTRACT: The SMRT (Silencing Mediator of Retinoid and Thyroid hormone receptors) corepressor mediates gene repression by nuclear receptors and other transcriptional factors. The SMRT protein serves as a key nucleating core that organizes the assembly of a larger corepressor complex. We report here that SMRT interacts with itself to form a protein dimer, and that Erk2, a mitogen-activated protein (MAP) kinase, disrupts this SMRT self-dimerization in vitro and in vivo. Notably Erk2 phosphorylation also results in a re-organization of the overall corepressor complex, characterized by a reduced sedimentation coefficient, partial release of HDAC3, TBL-1, and TBLR-1, and inhibition of transcriptional repression. We propose that SMRT dimers form the central platform on which additional corepressor compone

SUBMITTER: Varlakhanova N 

PROVIDER: S-EPMC3011023 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature