Nuclear receptor corepressor 1 (NCOR1) (NCOR1)

Nuclear receptor corepressor 1 (NCOR1) is a large, multi-domain scaffold protein that serves as a central hub for transcriptional repression. It functions by mediating the interaction between various nuclear receptors—such as the thyroid hormone receptor and retinoic acid receptor—and histone deacetylase complexes, specifically those containing HDAC3 (UniProt P42701). By recruiting these enzymes to target gene promoters, NCOR1 facilitates the removal of acetyl groups from histones, leading to chromatin condensation and the subsequent silencing of gene expression (PubMed: 21964338). This regulatory mechanism is vital for maintaining physiological balance in processes like metabolism, inflammation, and circadian rhythms. In clinical contexts, NCOR1 is frequently associated with the progression of various malignancies, including breast and prostate cancers, where it often acts as a tumor suppressor whose loss promotes hormone resistance and aggressive cellular behavior (PubMed: 29059175). Beyond oncology, its role in metabolic homeostasis makes it a significant factor in the development of obesity and insulin resistance (PubMed: 26829293). While NCOR1 is not typically the direct binding site for traditional small molecules, its function is central to the efficacy of HDAC inhibitors and selective nuclear receptor modulators. Recent drug discovery efforts have also begun exploring NCOR1 as a candidate for targeted protein degradation using PROTAC technology to selectively modulate transcriptional programs in disease states (PubMed: 33067605).

Other names

N-CoRN-CoR1Nuclear receptor corepressor 1TRAC-1RIP13KIAA1047

Recruitment of histone deacetylase 3 (HDAC3) and other corepressors to nuclear receptors and transcription factors to mediate gene silencing through chromatin remodeling (UniProt P42701).