Corepressor interacting with RBPJ 1 (CIR1)

May modulate splice site selection during alternative splicing of pre-mRNAs (By similarity). Regulates transcription and functions as corepressor for RBPJ.

Recruits RBPJ to the Sin3-histone deacetylase complex (HDAC). Required for RBPJ-mediated repression of transcription.