A new toggle switch model for 14-3-3ζ-dependent regulation of VWF binding function of GPIb-IX. Intracellular cAMP levels regulate VWF-dependent platelet adhesion by controlling the 14-3-3ζ binding states in a way similar to a toggle switch. Disruption of 14-3-3ζ interaction with GPIbα inhibits activation of VWF binding function of GPIb-IX and thus platelet adhesion. GP indicates glycoprotein.