Integrin beta 7
From Wikipedia, the free encyclopedia
Integrin beta-7 is an integrin protein that in humans is encoded by the ITGB7 gene.[5][6] It can pair with ITGA4 (CD49d) to form the heterodimeric integrin receptor α4β7, or with ITGAE (CD103) to form αEβ7.[7]
Structure
Like all integrin subunits, β7 is a highly flexible, membrane-bound, extracellular protein that must pair with an α subunit for stability. The molecule's flexibility allows it to dynamically regulate its affinity for ligand through conformational changes.[8] Beginning with the apical end of the protein, farthest from the cell membrane, the β7 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 βI domain, which, in combination with the α 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 β tail domain. Finally there is a transmembrane domain, and the C-terminal cytoplasmic tail.[9]