Ligand-dependent nuclear receptor corepressor LCoR functions by histone deacetylase-dependent and -independent mechanisms.

Department of Physiology, McGill University, Montreal, Quebec, Canada H3G 1Y6.
Molecular Cell (Impact Factor: 15.28). 02/2003; 11(1):139-50. DOI: 10.1016/S1097-2765(03)00014-5
Source: PubMed

ABSTRACT LCoR (ligand-dependent corepressor) is a transcriptional corepressor widely expressed in fetal and adult tissues that is recruited to agonist-bound nuclear receptors through a single LXXLL motif. LCoR binding to estrogen receptor alpha depends in part on residues in the coactivator binding pocket distinct from those bound by TIF-2. Repression by LCoR is abolished by histone deacetylase inhibitor trichostatin A in a receptor-dependent fashion, indicating HDAC-dependent and -independent modes of action. LCoR binds directly to specific HDACs in vitro and in vivo. Moreover, LCoR functions by recruiting C-terminal binding protein corepressors through two consensus binding motifs and colocalizes with CtBPs in the nucleus. LCoR represents a class of corepressor that attenuates agonist-activated nuclear receptor signaling by multiple mechanisms.

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