2VFX:
reference: Insights into Mad2 Regulation in the Spindle Checkpoint Revealed by the Crystal Structure of the Symmetric Mad2 Dimer., Yang M, Li B, Liu CJ, Tomchick DR, Machius M, Rizo J, Yu H, Luo X, PLoS Biol. 2008 Mar 4;6(3):e50. PMID: 18318601

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