Kinetic determination of focal adhesion protein formation.
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.
Goldmann
W H
WH
Department of Pathology and Department of Surgery, Harvard Medical School, Boston, Massachusetts, 02115, USA.
D000185:Actinin / Q000737:chemistry / Q000378:metabolism*; D000199:Actins / Q000737:chemistry / Q000378:metabolism*; D000818:Animals; D001792:Blood Platelets / Q000378:metabolism; D002645:Chickens; D003285:Contractile Proteins / Q000737:chemistry / Q000378:metabolism*; D003599:Cytoskeleton / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D064448:Filamins; D005895:Gizzard, Avian / Q000378:metabolism; D006801:Humans; D016023:Integrins / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D008840:Microfilament Proteins / Q000737:chemistry / Q000378:metabolism*; D009132:Muscles / Q000378:metabolism; D015539:Platelet Activation; D011485:Protein Binding; D011817:Rabbits; D013053:Spectrophotometry; D016608:Talin / Q000737:chemistry / Q000378:metabolism*; D017186:Titrimetry; D014421:Turkey; D016596:Vinculin / Q000737:chemistry / Q000378:metabolism*
D000199:Actins; D003285:Contractile Proteins; D064448:Filamins; D016023:Integrins; D008840:Microfilament Proteins; D016608:Talin; D000185:Actinin; D016596:Vinculin