Protein arginine N-methyltransferase 7 (PRMT7) is a member of the protein arginine N-methyltransferase (PRMT) family of proteins that catalyze the transfer of a methyl group from S-adenosylmethionine (AdoMet) to a guanidine nitrogen of arginine . The three types of PRMTs share the ability to mono-methylate arginine residues, but vary in their ability to generate differential methylation states . Mono-methylated arginine residues are further methylated by type I PRMTs to generate an asymmetric di-methyl arginine or by type II PRMTs to form a symmetric-dimethyl arginine. Type III methyltransferases are only able to mono-methylate arginine residues . Research studies indicate that PRMT7 is a type III PRMT that displays substrate specificity for an arginine-X-arginine (RXR) motif surrounded by several basic residues . PRMT7 interacts with a wide array of protein substrates and likely plays a role in many biological processes including pluripotency, neuronal differentiation, genomic instability, snRNP biogenesis, and breast cancer metastasis .