Members of this family are transcriptional coactivators that specifically associate with either OCT1 or OCT2, through recognition of their POU domains. They are essential for the response of B-cells to antigens and required for the formation of germinal centres [1].

1: Crystal structure of an OCA-B peptide bound to an Oct-1 POU domain/octamer DNA complex: specific recognition of a protein-DNA interface. Chasman D, Cepek K, Sharp PA, Pabo CO; Genes Dev. 1999;13:2650-2657. PMID:10541551