The peptide LSARLAF causes platelet secretion and aggregation by directly activating the integrin alphaIIbbeta3

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Updated: Nov 1, 2026

An In Vitro Assay to Study Platelet Migration Using RGD-Functionalized Avidin-Biotin Tethers
05:43

An In Vitro Assay to Study Platelet Migration Using RGD-Functionalized Avidin-Biotin Tethers

Published on: November 8, 2024

J M Derrick1, D B Taylor, R G Loudon

  • 1Microbiology and Molecular Cell Sciences, University of Memphis, Campus Box 526041, Memphis, TN 38152, USA.

The Biochemical Journal
|July 15, 1997
PubMed

A novel peptide (designed to bind to alphaIIbbeta3) caused platelet aggregation and aggregation-independent secretion of the contents of alpha-granules in an alphaIIbbeta3-dependent fashion. The agonist peptide induced secretion in the presence of prostaglandin E1. In cell-free assays, alphaIIbbeta3 bound specifically to immobilized agonist peptide and the peptide enhanced the binding of fibrinogen to immobilized alphaIIbbeta3. The agonist peptide apparently activates alphaIIbbeta3 by directly inducing a conformational change in the receptor. This change activates the platelets and causes secretion in a manner independent of fibrinogen binding.

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