3G7L:
reference: High-affinity binding of Chp1 chromodomain to K9 methylated histone H3 is required to establish centromeric heterochromatin., Schalch T, Job G, Noffsinger VJ, Shanker S, Kuscu C, Joshua-Tor L, Partridge JF, Mol Cell. 2009 Apr 10;34(1):36-46. PMID: 19362535

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