Plays a role in transcriptional regulation as a repressor that inhibits monoamine oxidase A (MAOA) activity and gene expression by binding to the promoter. Plays an important oncogenic role in mediating the full transforming effect of MYC in medulloblastoma cells. Involved in apoptotic signaling pathways; May act downstream of P38-kinase and BCL-2, but upstream of CASP3/caspase-3 as well as CCND1/cyclin D1 and E2F1 (By similarity). Interacts with MYC (By similarity). Interacts (via IBM motifs) with PSIP1 (via IBD domain); phosphorylation increases its affinity for PSIP1 (By similarity). Associates with chromatin. Translocates from cytoplasm to nucleus under dexamethasone induction (By similarity). Phosphorylation increases its interaction with PSIP1.