1S2H:
reference: The Mad2 spindle checkpoint protein has two distinct natively folded states., Luo X, Tang Z, Xia G, Wassmann K, Matsumoto T, Rizo J, Yu H, Nat Struct Mol Biol 2004 Apr;11(4):338-45. Epub 2004 Mar 14. PMID: 15024386

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