SMYD3 is a histone methyltransferase that plays a role in transcriptional regulation as a member of an RNA polymerase complex.SMYD3 is a histone methyltransferase that plays a role in transcriptional regulation as a member of an RNA polymerase complex.[supplied by OMIM]. Publication Note: This RefSeq record includes a subset of the publications that are available for this gene. Please see the Entrez Gene record to access additional publications.