Mechanisms Regulating Acquisition of Platelet-Derived Factor V/Va by Megakaryocytes.

Abstract

Factor Va serves as the nonenzymatic protein cofactor for the prothrombinase complex, which converts prothrombin to thrombin in the events leading to formation of a hemostatic plug. Several observations support the concept that platelet-derived factor V/Va is physically and functionally distinct and plays a more important role in thrombin generation at sites of vascular injury as compared to its plasma counterpart. Platelet-derived factor V/Va is generated following endocytosis of the plasma-derived molecule by the platelet precursor cells, megakaryocytes, via a two receptor system consisting of low density lipoprotein (LDL) receptor-related protein-1 (LRP-1) and an unidentified specific "binding site". More recently, it was suggested that a cell surface-expressed β-galactoside binding protein, galectin-8, was involved in factor V endocytosis. Endocytosed factor V is trafficked through the cell and retailored prior to its storage in α-granules. Given the essential role of platelet-derived factor Va in clot formation, understanding the cellular and molecular mechanisms that regulate how platelets acquire this molecule will be important for the treatment of excessive bleeding or clotting.

• Authors: Jacqueline M Gertz, Beth A Bouchard
• Journal: Journal of cellular biochemistry (J Cell Biochem) Vol. 116 Issue 10 Pg. 2121-6 (Oct 2015) ISSN: 1097-4644 [Electronic] United States
• PMID: 25800007 (Publication Type: Journal Article, Research Support, N.I.H., Extramural, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 Wiley Periodicals, Inc.

Chemical References

• Blood Coagulation Factors
• Galectins
• LDLR-related protein 1A, human
• LGALS8 protein, human
• Low Density Lipoprotein Receptor-Related Protein-1
• platelet factor V
• Thrombin

Topics

• Blood Coagulation (genetics)
• Blood Coagulation Factors (genetics, metabolism)
• Blood Platelets (metabolism, pathology)
• Endocytosis (genetics)
• Galectins (metabolism)
• Hemorrhage (genetics, metabolism, pathology)
• Humans
• Low Density Lipoprotein Receptor-Related Protein-1 (metabolism)
• Megakaryocytes (metabolism)
• Thrombin (metabolism)
• Vascular System Injuries (metabolism, pathology)