InterPro domain: IPR013517

This region contains the extracellular repeat that is found in up to seven copies in alpha integrins and related proteins. It forms a 7-fold repeat that adopts a beta-propeller structure [ 1 ]. The repeat is called the FG-GAP repeat after two conserved motifs in the repeat [ 2 ]. The FG-GAP repeats are found in the N terminus of integrin alpha chains, a region that has been shown to be important for ligand binding [ 2 ]. A putative Ca2+ binding motif is found in some of the repeats. These repeats are found in multiple proteins from eukaryotes and bacteria and mediate diverse biological processes at both molecular and cellular levels, such as cell-cell interactions, host patogen recognition or innate immune responses.

1. Integrin-mediated cell adhesion: the extracellular face. J. Biol. Chem. 269, 25235-8
2. Folding of the N-terminal, ligand-binding region of integrin alpha-subunits into a beta-propeller domain. Proc. Natl. Acad. Sci. U.S.A. 94, 65-72