Amino acid sequences of the predicted W3 4-1 loop between the N-terminal repeats 2 and 3 and the predicted W3 2-3 loop within repeat 3 in the α subunits of β₃ integrins.

Both loops are located on the upper face of the β-propeller model.20 The asterisks indicate that the residues were substituted by alanine in this study. This figure is adapted from a β-propeller model proposed by Springer,20 and the arrows indicate β strands.