3PDN:
reference: Structural Insights into the Autoinhibition and Posttranslational Activation of Histone Methyltransferase SmyD3., Sirinupong N, Brunzelle J, Doko E, Yang Z, J Mol Biol. 2010 Dec 15. PMID: 21167177

This OCA Structure page
uses Jmol, developed by the Jmol Development Team (documentation).