CARM1 Protein, Human (His)

CARM1 is a methyltransferase that mono- and asymmetrically dimethylates arginine residues in proteins involved in DNA packaging, transcription regulation, pre-mRNA splicing, and mRNA stability. It collaborates with EP300/P300 and p160 family histone acetyltransferases to methylate histone H3 at Arg-17 (H3R17me, primarily forming H3R17me2a), activating transcription via chromatin remodeling. During nuclear hormone receptor or TCF7L2/TCF4 activation, CARM1 synergizes with EP300/P300 and p160 acetyltransferases (e.g., NCOA1/SRC1, NCOA2/GRIP1, NCOA3/ACTR) or CTNNB1/beta-catenin to enhance transcription (by similar). In myogenic activation, it acts as a coactivator for MEF2C with NCOA3/ACTR (by similar). It also participates in monocyte inflammatory responses, PPARG-mediated adipocyte differentiation, pre-mRNA splicing regulation, and p53/TP53 transcriptional activation (by similar). CARM1 methylates EP300/P300 at specific arginine sites, disrupting its interaction with CREB, and modifies RNA-binding proteins (e.g., PABPC1, ELAVL1, ELAV4), potentially affecting mRNA stability. Independently of its methyltransferase activity, CARM1 promotes PARP1 recruitment to replication forks, slowing fork progression (PubMed:33412112).