Protein interactions with the platelet integrin alpha(IIb) regulatory motif

Proteomics. 2010 Aug;10(15):2790-800. doi: 10.1002/pmic.200900621.

Abstract

Integrins are transmembrane proteins regulating cellular shape, mobility and the cell cycle. A highly conserved signature motif in the cytoplasmic tail of the integrin alpha-subunit, KXGFFKR, plays a critical role in regulating integrin function. To date, six proteins have been identified that target this motif of the platelet-specific integrin alpha(IIb)beta(3). We employ peptide-affinity chromatography followed-up with LC-MS/MS analysis as well as protein chips to identify new potential regulators of integrin function in platelets and put them into their biological context using information from protein:protein interaction (PPI) databases. Totally, 44 platelet proteins bind with high affinity to an immobilized LAMWKVGFFKR-peptide. Of these, seven have been reported in the PPI literature as interactors with integrin alpha-subunits. 68 recombinant human proteins expressed on the protein chip specifically bind with high affinity to biotin-tagged alpha-integrin cytoplasmic peptides. Two of these proteins are also identified in the peptide-affinity experiments, one is also found in the PPI databases and a further one is present in the data to all three approaches. Finally, novel short linear interaction motifs are common to a number of proteins identified.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Blood Platelets / metabolism*
  • Chromatography, Affinity / methods
  • Chromatography, Liquid
  • Humans
  • Integrin alpha2 / metabolism*
  • Molecular Sequence Data
  • Peptides / metabolism
  • Protein Interaction Mapping* / methods
  • Proteins / metabolism*
  • Tandem Mass Spectrometry

Substances

  • ITGA2B protein, human
  • Integrin alpha2
  • Peptides
  • Proteins