4KEK:
reference: Type 2 Ryanodine Receptor Domain A Contains a Unique and Dynamic alpha-Helix That Transitions to a beta-Strand in a Mutant Linked with a Heritable Cardiomyopathy., Amador FJ, Kimlicka L, Stathopulos PB, Gasmi-Seabrook GM, Maclennan DH, Van Petegem F, Ikura M, J Mol Biol. 2013 Aug 23. pii: S0022-2836(13)00535-4. doi:, 10.1016/j.jmb.2013.08.015. PMID: 23978697

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