3KL8:
reference: Intersubunit capture of regulatory segments is a component of cooperative CaMKII activation., Chao LH, Pellicena P, Deindl S, Barclay LA, Schulman H, Kuriyan J, Nat Struct Mol Biol. 2010 Mar;17(3):264-72. Epub 2010 Feb 7. PMID: 20139983

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