Roles of SLP-76, phosphoinositide 3-kinase, and gelsolin in the platelet shape changes initiated by the collagen receptor GPVI/FcR gamma-chain complex

Blood. 2000 Dec 1;96(12):3786-92.

Abstract

How platelet shape change initiated by a collagen-related peptide (CRP) specific for the GPVI/FcR gamma-chain complex (GPVI/FcR gamma-chain) is coupled to SLP-76, phosphoinositide (PI) 3-kinase, and gelsolin is reported. As shown by video microscopy, platelets rapidly round and grow dynamic filopodial projections that rotate around the periphery of the cell after they contact a CRP-coated surface. Lamellae subsequently spread between the projections. All the actin-driven shape changes require SLP-76 expression. SLP-76 is essential for the Ca(++) mobilization induced by CRP, whereas PI 3-kinase only modulates it. The extension of lamellae requires net actin assembly and an exposure of actin filament barbed ends downstream of PI 3-kinase. Gelsolin expression is also required for the extension of lamellae, but not for the formation of filopodia. Altogether, the data describe the role of SLP-76 in the platelet activation initiated by GPVI/FcR gamma-chain and the roles of PI 3-kinase and gelsolin in lamellae spreading. (Blood. 2000;96:3786-3792)

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Actin Cytoskeleton / drug effects
  • Actins / drug effects
  • Actins / metabolism
  • Actins / physiology
  • Adaptor Proteins, Signal Transducing
  • Animals
  • Blood Platelets / cytology
  • Blood Platelets / drug effects*
  • Blood Platelets / ultrastructure
  • Calcium Signaling / drug effects
  • Cell Size / drug effects
  • Collagen / chemistry
  • Collagen / metabolism
  • Collagen / pharmacology
  • Gelsolin / pharmacology
  • Gelsolin / physiology*
  • Humans
  • Integrins / metabolism
  • Integrins / physiology
  • Mice
  • Mice, Mutant Strains
  • Peptide Fragments / metabolism
  • Peptide Fragments / pharmacology
  • Phosphatidylinositol 3-Kinases / metabolism
  • Phosphatidylinositol 3-Kinases / physiology*
  • Phosphoproteins / pharmacology
  • Phosphoproteins / physiology*
  • Platelet Activation / drug effects
  • Platelet Membrane Glycoproteins / metabolism
  • Platelet Membrane Glycoproteins / physiology*
  • Receptors, Collagen
  • Receptors, IgG / metabolism
  • Receptors, IgG / physiology*
  • Receptors, Thrombin / physiology
  • Signal Transduction

Substances

  • Actins
  • Adaptor Proteins, Signal Transducing
  • Gelsolin
  • Integrins
  • Peptide Fragments
  • Phosphoproteins
  • Platelet Membrane Glycoproteins
  • Receptors, Collagen
  • Receptors, IgG
  • Receptors, Thrombin
  • SLP-76 signal Transducing adaptor proteins
  • platelet membrane glycoprotein VI
  • Collagen
  • Phosphatidylinositol 3-Kinases