3J8E:
reference: Structure of a mammalian ryanodine receptor., Zalk R, Clarke OB, Georges AD, Grassucci RA, Reiken S, Mancia F, Hendrickson WA, Frank J, Marks AR, Nature. 2014 Dec 1. doi: 10.1038/nature13950. PMID: 25470061

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