4GIQ:
reference: RANKL Employs Distinct Binding Modes to Engage RANK and the Osteoprotegerin Decoy Receptor., Nelson CA, Warren JT, Wang MW, Teitelbaum SL, Fremont DH, Structure. 2012 Oct 2. pii: S0969-2126(12)00334-6. doi:, 10.1016/j.str.2012.08.030. PMID: 23039992

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