Integrin Beta 7 (ITGb7)

Like all integrin subunits, ITGb7 is a highly flexible, membrane-bound, extracellular protein that must pair with an alpha subunit for stability. The molecule's flexibility allows it to dynamically regulate its affinity for ligand through conformational changes. Beginning with the apical end of the protein, farthest from the cell membrane, the beta7 is composed of a head and upper legs, collectively known as the headpiece, lower legs, a transmembrane domain and a cytoplasmic tail. The top of the head is the I-like domain, sometimes called the betaI domain, which, in combination with the alpha subunit, binds ligand. Just below this is the hybrid domain, a portion of which is N-terminal to the I-like domain. Below the hybrid domain is the PSI domain, which completes the headpiece. The lower legs consist of EGF domains 1-4 and the beta tail domain.