Identification of motifs in the fasciclin domains of the transforming growth factor-beta-induced matrix protein betaig-h3 that interact with the alphavbeta5 integrin

J Biol Chem. 2002 Nov 29;277(48):46159-65. doi: 10.1074/jbc.M207055200. Epub 2002 Sep 21.

Abstract

betaig-h3 is a TGF-beta-induced matrix protein known to mediate the adhesion of several cell types. In this study, we found that all four of the fas-1 domains in betaig-h3 mediate MRC-5 fibroblast adhesion and that this was specifically inhibited by a function-blocking monoclonal antibody specific for the alphavbeta5 integrin. Using deletion mutants of the fourth fas-1 domain revealed the MRC-5 cell adhesion motif (denoted the YH motif) is located in amino acids 548-614. Experiments with substitution mutants showed that tyrosine 571, histidine 572, and their flanking leucine and isoleucine amino acids, which are all highly conserved in many fas-1 domains, are essential for mediating MRC-5 cell adhesion. A synthetic 18-amino acid peptide encompassing these conserved amino acids could effectively block MRC-5 cell adhesion to betaig-h3. Using HEK293 cells stably transfected with the beta5 integrin cDNA, we confirmed that the alphavbeta5 integrin is a functional receptor for the YH motif. In conclusion, we have identified a new alphavbeta5 integrin-interacting motif that is highly conserved in the fas-1 domains of many proteins. This suggests that fas-1 domain-containing proteins may perform their biological functions by interacting with integrins.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs*
  • Amino Acid Sequence
  • Cells, Cultured
  • Elapid Venoms / chemistry
  • Elapid Venoms / metabolism*
  • Extracellular Matrix Proteins*
  • Flow Cytometry
  • Humans
  • Integrins / metabolism*
  • Molecular Sequence Data
  • Neoplasm Proteins / metabolism*
  • Protein Binding
  • Receptors, Vitronectin / metabolism*
  • Sequence Homology, Amino Acid
  • Transforming Growth Factor beta*

Substances

  • Elapid Venoms
  • Extracellular Matrix Proteins
  • Integrins
  • Neoplasm Proteins
  • Receptors, Vitronectin
  • Transforming Growth Factor beta
  • integrin alphaVbeta5
  • betaIG-H3 protein
  • fasciculin