Protein arginine N-methyltransferase 1 (PRMT1)

Arginine methyltransferase that methylates (mono and asymmetric dimethylation) that the guanidino nitrogens of arginyl residues present in proteins such as ESR1, histone H2, H3 and H4, PIAS1, HNRNPA1, HNRNPD, NFATC2IP, SUPT5H, TAF15, EWS, HABP4 and SERBP1 (PubMed:16879614, PubMed:26876602). Constitutes the main enzyme that mediates monomethylation and asymmetric dimethylation of histone H4'Arg-4' (H4R3me1 and H4R3me2a, respectively), a specific tag for epigenetic transcriptional activation.

Together with dimethylated PIAS1, represses STAT1 transcriptional activity, in the late phase of interferon gamma (IFN-gamma) signaling. May be involved in the regulation of TAF15 transcriptional activity, serve as an activator of estrogen receptor (ER)-mediated transactivation, play an integral role in neurite outgrowth and act as a negative regulator of megakaryocytic differentiation, by regulating p38 MAPK pathway.