Crystal structure of the extracellular segment of integrin alpha Vbeta3

Science. 2001 Oct 12;294(5541):339-45. doi: 10.1126/science.1064535. Epub 2001 Sep 6.


Integrins are alphabeta heterodimeric receptors that mediate divalent cation-dependent cell-cell and cell-matrix adhesion through tightly regulated interactions with ligands. We have solved the crystal structure of the extracellular portion of integrin alphaVbeta3 at 3.1 A resolution. Its 12 domains assemble into an ovoid "head" and two "tails." In the crystal, alphaVbeta3 is severely bent at a defined region in its tails, reflecting an unusual flexibility that may be linked to integrin regulation. The main inter-subunit interface lies within the head, between a seven-bladed beta-propeller from alphaV and an A domain from beta3, and bears a striking resemblance to the Galpha/Gbeta interface in G proteins. A metal ion-dependent adhesion site (MIDAS) in the betaA domain is positioned to participate in a ligand-binding interface formed of loops from the propeller and betaA domains. MIDAS lies adjacent to a calcium-binding site with a potential regulatory function.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Binding Sites
  • Calcium / metabolism
  • Crystallization
  • Crystallography, X-Ray
  • Dimerization
  • Humans
  • Ligands
  • Metals / metabolism
  • Models, Molecular
  • Molecular Sequence Data
  • Mutation
  • Protein Conformation
  • Protein Folding
  • Protein Structure, Quaternary
  • Protein Structure, Secondary
  • Protein Structure, Tertiary
  • Protein Subunits
  • Receptors, Vitronectin / chemistry*
  • Receptors, Vitronectin / genetics
  • Receptors, Vitronectin / metabolism
  • Sequence Alignment


  • Ligands
  • Metals
  • Protein Subunits
  • Receptors, Vitronectin
  • Calcium

Associated data