nuclear receptor corepressor 2; N-CoR2; silencing mediator of retinoic acid & thyroid hormone receptor; SMRT; thyroid-, retinoic-acid-receptor-associated corepressor; T3 receptor-associating factor; TRAC; CTG repeat protein 26; SMAP270 (NCOR2, CTG26)

Function

• interacts with unliganded nuclear receptors, including RXR, RAR, T3R, PPAR-alpha & PPAR-gamma to keep them in a repressed state
• mediates transcriptional repression activity of some nuclear receptors by promoting chromatin condensation, thus preventing access of the basal transcription
• isoform 1 & isoform 5 have different affinities for different nuclear receptors
• interacts with HDAC7 (putative)
• forms a large corepressor complex that contains SIN3A/B & histone deacetylases HDAC1 & HDAC2
  • this complex associates with the thyroid hormone receptor (erbA) and the retinoid acid receptors (RAR) in the absence of ligand, & may stabilize their interaction with TFIIB
• isoform SRMT interacts with HDAC10
• interacts with MINT
• component of the N-cor repressor complex
• interacts with CBFA2T3
• interacts with C1D
• interacts with ATXN1L
• interacts with BCL6 (directly)

Structure

• the N-terminal region contains repression functions that are divided into 3 independent repression domains (RD1, RD2 & RD3)
• the C-terminal region contains the nuclear receptor-interacting domains that are divided in 2 separate interaction domains (ID1 & ID2)
• the 2 interaction domains (ID) contain a conserved sequence referred to as the CORNR box
  • the CORNR box is required & sufficient to permit binding to unligated erbA & RAR
  • sequences flanking the CORNR box determine nuclear hormone receptor specificity
• belongs to the N-CoR nuclear receptor corepressors family
• contains 2 SANT domains

Compartment

nucleus

Alternative splicing

• named isoforms=5
• contains only the C-terminal receptor-interacting domain & acts as an antirepressor

Expression

• ubiquitous
• high levels of expression are detected in lung, spleen & brain
• regulated during cell cycle progression

Pathology

• loss of NCOR2 expression may accelerate resistance to androgen deprivation therapy in prostate cancer

More general terms

• nuclear receptor corepressor (N-COR)
• phosphoprotein

Component of

• N-cor repressor complex

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=9612
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:9612
• OMIM: https://mirror.omim.org/entry/600848
• UniProt: http://www.uniprot.org/uniprot/Q9Y618.html