3JC2:
reference: Structure of the Sec61 channel opened by a signal sequence., Voorhees RM, Hegde RS, Science. 2016 Jan 1;351(6268):88-91. doi: 10.1126/science.aad4992. PMID: 26721998

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