1ZKK:
reference: Structural and functional analysis of SET8, a histone H4 Lys-20 methyltransferase., Couture JF, Collazo E, Brunzelle JS, Trievel RC, Genes Dev 2005 Jun 15;19(12):1455-65. Epub 2005 Jun 2. PMID: 15933070

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