Table of Contents
Journal of Signal Transduction
Volume 2012, Article ID 412089, 9 pages
Review Article

The Small GTPase Rap1b: A Bidirectional Regulator of Platelet Adhesion Receptors

Department of Biology and Biotechnology, Division of Biochemistry, University of Pavia, Via Bassi 21, 27100 Pavia, Italy

Received 23 February 2012; Revised 12 April 2012; Accepted 27 April 2012

Academic Editor: Kris DeMali

Copyright © 2012 Gianni Francesco Guidetti and Mauro Torti. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


Integrins and other families of cell adhesion receptors are responsible for platelet adhesion and aggregation, which are essential steps for physiological haemostasis, as well as for the development of thrombosis. The modulation of platelet adhesive properties is the result of a complex pattern of inside-out and outside-in signaling pathways, in which the members of the Rap family of small GTPases are bidirectionally involved. This paper focuses on the regulation of the main Rap GTPase expressed in circulating platelets, Rap1b, downstream of adhesion receptors, and summarizes the most recent achievements in the investigation of the function of this protein as regulator of platelet adhesion and thrombus formation.