3P73:
reference: Structure of a classical MHC class I molecule that binds "non-classical" ligands., Hee CS, Gao S, Loll B, Miller MM, Uchanska-Ziegler B, Daumke O, Ziegler A, PLoS Biol. 2010 Dec 7;8(12):e1000557. PMID: 21151886

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