Anti-corepressor interacting with RBPJ, CIR1 antibodies are used for the immunodetection of the protein encoded by the CIR1 gene. In humans, the canonical protein has a reported length of 450 amino acid residues and a mass of 52.3 kDa. Its subcellular localization is in the nucleus and cytoplasm. Alternative splicing is reported to yield 2 different isoforms for this protein. It is reported to be highly expressed in the heart, brain, placenta, liver, skeletal muscle and pancreas. It is believed to modulate splice site selection during alternative splicing of pre-mRNAs (By similarity). Post-translational modifications have been described, including phosphorylation. Other names for this target antigen include corepressor interacting with RBPJ 1, CBF1 (RBPJ) interacting corepressor 1, CBF1-interacting corepressor, corepressor interacting with RBPJ, 1, recepin, and CIR. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.