Tumor suppressor that inhibits cell proliferation and promotes apoptosis. Modulates the activity of protein arginine N-methyltransferases, including PRMT3 and PRMT5. Interacts (via FERM domain) with CADM1 (PubMed:12234973, PubMed:21131357). Interacts (via FERM domain) with PRMT3; the interaction is direct and inhibits the protein-arginine N-methyltransferase activity of PRMT3 (PubMed:15334060). Interacts with PRMT5 (PubMed:15334060, PubMed:15737618). Interacts with PRMT6 (PubMed:15334060). Detected in the cytoplasm of actively dividing cells. Additional isoforms seem to exist. Expressed at high levels in brain, with lower levels in kidney, intestine, and testis. Detected in lung. Extended N-terminus.