This gene encodes an enzyme that belongs to the methyltransferase family. The encoded protein catalyzes the transfer of methyl groups to the amino acid arginine, in target proteins that include histones, transcriptional elongation factors and the tumor suppressor p53. This gene plays a role in several cellular processes, including transcriptional regulation, and the assembly of small nuclear ribonucleoproteins. A pseudogene of this gene has been defined on chromosome 4. Alternative splicing results in multiple transcript variants encoding different isoforms.