14-3-3? regulates the mitochondrial respiratory reserve linked to platelet phosphatidylserine exposure and procoagulant function.

ABSTRACT: The 14-3-3 family of adaptor proteins regulate diverse cellular functions including cell proliferation, metabolism, adhesion and apoptosis. Platelets express numerous 14-3-3 isoforms, including 14-3-3?, which has previously been implicated in regulating GPIb? function. Here we show an important role for 14-3-3? in regulating arterial thrombosis. Interestingly, this thrombosis defect is not related to alterations in von Willebrand factor (VWF)-GPIb adhesive function or platelet activation, but instead associated with reduced platelet phosphatidylserine (PS) exposure and procoagulant function. Decreased PS exposure in 14-3-3?-deficient platelets is associated with more sustained levels of metabolic ATP and increased mitochondrial respiratory reserve, independent of alterations in cytosolic calcium flux. Reduced platelet PS exposure in 14-3-3?-deficient mice does not increase bleeding risk, but results in decreased thrombin generation and protection from pulmonary embolism, leading to prolonged survival. Our studies define an important role for 14-3-3? in regulating platelet bioenergetics, leading to decreased platelet PS exposure and procoagulant function.

SUBMITTER: Schoenwaelder SM 

PROVIDER: S-EPMC5052641 | biostudies-literature | 2016 Sep

REPOSITORIES: biostudies-literature