Kinetic determination of focal adhesion protein formation

Biochem Biophys Res Commun. 2000 May 10;271(2):553-7. doi: 10.1006/bbrc.2000.2653.

Abstract

I examined the binding kinetics between integrin (alpha(IIb)beta(3)) and purified focal adhesion proteins, including alpha-actinin, filamin, vinculin, talin, and F-actin. Using static light-scatter technique, I observed affinities of the order talin > filamin > F-actin > alpha-actinin > (talin when bound to vinculin) which were lower when integrin was complexed with fibronectin. No binding between integrin and vinculin was detected. The calculated dissociation constants (K(d)) ranged between 0.4 microM and 5 microM. These results in part confirm previously published data using different methods. The modest affinity with which the focal adhesion proteins interact in vitro might be indicative of how cells, e.g., thrombocytes, gain a high degree of versatility and velocity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Actinin / chemistry
  • Actinin / metabolism*
  • Actins / chemistry
  • Actins / metabolism*
  • Animals
  • Blood Platelets / metabolism
  • Chickens
  • Contractile Proteins / chemistry
  • Contractile Proteins / metabolism*
  • Cytoskeleton / metabolism
  • Electrophoresis, Polyacrylamide Gel
  • Filamins
  • Gizzard, Avian / metabolism
  • Humans
  • Integrins / chemistry
  • Integrins / metabolism*
  • Kinetics
  • Microfilament Proteins / chemistry
  • Microfilament Proteins / metabolism*
  • Muscles / metabolism
  • Platelet Activation
  • Protein Binding
  • Rabbits
  • Spectrophotometry
  • Talin / chemistry
  • Talin / metabolism*
  • Titrimetry
  • Turkey
  • Vinculin / chemistry
  • Vinculin / metabolism*

Substances

  • Actins
  • Contractile Proteins
  • Filamins
  • Integrins
  • Microfilament Proteins
  • Talin
  • Actinin
  • Vinculin