4JZY:
reference: Structures of Drosophila cryptochrome and mouse cryptochrome1 provide insight into circadian function., Czarna A, Berndt A, Singh HR, Grudziecki A, Ladurner AG, Timinszky G, Kramer A, Wolf E, Cell. 2013 Jun 6;153(6):1394-405. doi: 10.1016/j.cell.2013.05.011. PMID: 23746849

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