PRMT

PRMT stands for protein arginine methyltransferases, a family of S-adenosyl-L-methionine–dependent enzymes that add methyl groups to arginine residues on substrate proteins. This post-translational modification can alter protein interactions, localization, and function, and it occurs on a broad range of targets, including histones and various non-histone proteins involved in transcription, RNA processing, and signaling. PRMTs are conserved across eukaryotes and play essential roles in development and cellular homeostasis.

PRMTs are historically classified into three types based on their methylation products. Type I enzymes catalyze asymmetric dimethylation (ADMA) of arginine, Type II enzymes catalyze symmetric dimethylation (SDMA), and Type III enzymes primarily generate monomethylated arginine. In humans, notable members include PRMT1 and PRMT4/CARM1 as Type I enzymes; PRMT5 as a prominent Type II enzyme that often forms a functional complex with the cofactor MEP50 (WD repeat-containing protein 77); and PRMT7 as a Type III enzyme that mainly generates monomethylarginine. The specific substrate preferences and complex formation patterns contribute to diverse regulatory outcomes in chromatin remodeling, RNA processing, and signaling pathways.

Biological roles of PRMTs are broad and context-dependent. They regulate chromatin structure and gene expression through histone arginine methylation, influence RNA splicing by modifying splicing factors, and participate in DNA damage response and cytoskeletal dynamics. PRMT activity is controlled at multiple levels, including expression, subcellular localization, post-translational modifications, and interactions with partner proteins or other chromatin modifiers.

Dysregulation of PRMT activity has been linked to various diseases, notably cancer, cardiovascular disorders, and neurodegenerative conditions. Because of their wide-ranging influence on cellular processes, PRMTs are actively studied as potential therapeutic targets, and several small-molecule inhibitors and chemical probes have been developed to probe their function and explore clinical applications.