Model of the αIIb β-propeller showing calcium-binding mutations and cage residues.

A model of the αIIb β-propeller was generated as described in “Patients, materials, and methods.” (A) Top view of the propeller showing the 7 blades (W1-W7), the 4 calcium ions (yellow), and the locations of 7 reported calcium-binding domain mutations (black and cyan spheres; mutations identified in this study are cyan). (B) Side view of the propeller with the mutations labeled. (C) Blades W4-W7 are viewed from the side. The 2 critical cage residues are displayed. A sphere centered on the amino acid α-carbon identifies the positions of each calcium-binding domain mutation. This figure was generated with MOLMOL.36