Baustatik
Structural analysis of the MadCAM-1 protein shows that it is a 41.5 kDa transmembrane protein with a small cytoplasmic tail and a large extracellular region. This extracellular region includes three immunoglobin-like (Ig) domains. The last of which has 33% structural identity to the Ca2 domain of IgA-1. The first two of the domains are predicted to be the most important in the α4β7 interaction.