title: Advances in platelet granule biology.
abstract: OBJECTIVE
  This review will provide an overview of several recent advances in the field of platelet granule biology.
  
  
  RESULTS
  The past few years have witnessed a substantial evolution in our knowledge of platelet granules based on a number of discoveries and new experimental approaches. This article will cover recent studies in five areas. First, the vesicle trafficking pathways responsible for α-granule formation are beginning to be assembled as a result of the characterization of patients with α-granule deficiencies. Second, a revision of our understanding of which SNARE isoforms mediate platelet granule exocytosis has occurred following evaluation of patients with defects in platelet granule exocytosis and the generation of mice lacking specific SNAREs. Third, investigators have begun to establish how cargos are segregated among α-granules and determine whether or not different α-granule subpopulations exist in platelets. Fourth, an unanticipated role for α-granules in platelet spreading has been identified. Fifth, single-cell amperometry has revealed secretion kinetics with submillisecond temporal resolution enabling evaluation of the molecular control of the platelet fusion pore.
  
  
  CONCLUSIONS
  These new observations reveal a previously unappreciated complexity to platelet granule formation and exocytosis and challenge our earlier notions of how these granules are organized within platelets and contribute to the multitude of physiological activities in which platelets function.
authors.affiliation: Division of Hemostasis and Thrombosis, Department of Medicine, BIDMC, Harvard Medical School, Boston, Massachusetts 02215, USA.
authors.forename: Secil
authors.initials: S
authors.lastname: Koseoglu
authors.forename: Robert
authors.initials: R
authors.lastname: Flaumenhaft
mesh_terms: D001792:Blood Platelets / Q000502:physiology*; D003594:Cytoplasmic Granules / Q000502:physiology*; D006801:Humans; D021381:Protein Transport / Q000502:physiology*; D050600:SNARE Proteins / Q000502:physiology
chemical_list: D050600:SNARE Proteins