1A1N:
reference: An altered position of the alpha 2 helix of MHC class I is revealed by the crystal structure of HLA-B*3501., Smith KJ, Reid SW, Stuart DI, McMichael AJ, Jones EY, Bell JI, Immunity 1996 Mar;4(3):203-13. PMID: 8624811

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