2BE6:
reference: Insights into voltage-gated calcium channel regulation from the structure of the Ca(V)1.2 IQ domain-Ca(2+)/calmodulin complex., Van Petegem F, Chatelain FC, Minor DL, Nat Struct Mol Biol 2005 Dec;12(12):1108-1115. Epub 2005 Nov 20. PMID: 16299511

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