Recombinant Smyd4 (accession number NP_443160.2) was expressed in Sf9 cells and contains an N-terminal FLAG tag with an observed molecular weight of 90.9 kDa. SET and MYND domain-containing protein 4 (Smyd4) is a member of the Smyd family of histone methyltransferases that may function as a potential tumor suppressor in breast cancer cells.