A1 Journal article – refereed
"RKKH" peptides from the snake venom metalloproteinase of Bothrops jararaca bind near the metal ion-dependent adhesion site of the human integrin alpha(2) I-domain




List of Authors: Pentikainen O, Hoffren AM, Ivaska J, Kapyla J, Nyronen T, Heino J, Johnson MS
Publisher: AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC
Publication year: 1999
Journal: Journal of Biological Chemistry
Journal name in source: JOURNAL OF BIOLOGICAL CHEMISTRY
Journal acronym: J BIOL CHEM
Volume number: 274
Number of pages: 13
ISSN: 0021-9258

Abstract
Integrin alpha(1)beta(1) and alpha(2)beta(1) are the major cellular receptors for collagen, and collagens bind to these integrins at the inserted I-domain in their cw subunit. We have previously shown that a cyclic peptide derived from the metalloproteinase domain of the snake venom protein jararhagin blocks the collagen-binding function of the alpha(2) I-domain. Here, we have optimized the structure of the peptide and identified the site where the peptide binds to the alpha(2) I-domain. The peptide sequence Arg-Lys-Lys-His is critical for recognition by the I-domain, and five negatively charged residues surrounding the "metal ion-dependent adhesion site" (MIDAS) of the I-domain, when mutated, show significantly impaired binding of the peptide. Removal of helix alpha C, located along one side of the MIDAS and suggested to be involved in collagen-binding in these I-domains, does not affect peptide binding. This study supports the notion that the metalloproteinase initially binds to the alpha(2) I-domain at a location distant from the active site of the protease, thus blocking collagen binding to the adhesion molecule in the vicinity of the MIDAS, while at the same time leaving the active site free to degrade nearby proteins, the closest being the beta(1) subunit of the alpha(2)beta(1) cell-surface integrin itself.

Last updated on 2019-21-08 at 20:35