Acts as a transcriptional corepressor in a IRF2-dependent manner; this repression is not mediated by histone deacetylase activities (PubMed:12799427). Represses the NFAT1-dependent transactivation of NFAT-responsive promoters (PubMed:21576369). Acts as a coactivator of VEGFA expression in cardiac and skeletal muscles (PubMed:20702774). Plays a role in immature B-cell differentiation (PubMed:27016798). Interacts with IRF2. Part of a corepressor complex containing IRF2 and IRF2BP1. Interacts with VGLL4. The C-terminal RING-type zinc finger domain is sufficient for interaction with IRF2. Phosphorylation at Ser-360 is required for nuclear targeting. The disease is caused by variants affecting the gene represented in this entry. Belongs to the IRF2BP family.