title: The platelet microparticle proteome.
abstract: Platelet-derived microparticles are the most abundant type of microparticle in human blood and contribute to many biologically significant processes. Here, we report the first proteomic analysis of microparticles generated from activated platelets. Using 1D SDS-PAGE and liquid chromatography coupled to a linear ion trap mass spectrometer, the identification of 578 proteins was accomplished using a minimum of 5 MS/MS detections of at least two different peptides for each protein. These microparticles displayed many proteins intrinsic to and well-characterized on platelets. For example, microparticles in these experiments were found to contain membrane surface proteins including GPIIIa, GPIIb, and P-selectin, as well other platelet proteins such as the chemokines CXCL4, CXCL7, and CCL5. In addition, approximately 380 of the proteins identified were not found in two previous studies of the platelet proteome. Since several of the proteins detected here have been previously implicated in microparticle formation and/or pathological function, it is hoped that this study will help fuel future work concerning the possible role of microparticles in various disease states.
authors.affiliation: Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
authors.forename: Benjamin A
authors.initials: BA
authors.lastname: Garcia
authors.forename: David M
authors.initials: DM
authors.lastname: Smalley
authors.forename: Hyungjun
authors.initials: H
authors.lastname: Cho
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Shabanowitz
authors.forename: Klaus
authors.initials: K
authors.lastname: Ley
authors.forename: Donald F
authors.initials: DF
authors.lastname: Hunt
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000378:metabolism*; D002469:Cell Separation; D018946:Chemokine CCL5; D019742:Chemokines, CC / Q000737:chemistry; D002853:Chromatography, Liquid; D004591:Electrophoresis, Polyacrylamide Gel; D005434:Flow Cytometry; D006801:Humans; D039661:Integrin beta3 / Q000737:chemistry; D013058:Mass Spectrometry; D019007:P-Selectin / Q000737:chemistry; D010455:Peptides / Q000737:chemistry; D010974:Platelet Aggregation; D010978:Platelet Factor 4 / Q000737:chemistry; D019038:Platelet Glycoprotein GPIb-IX Complex / Q000737:chemistry; D010980:Platelet Membrane Glycoproteins / Q000737:chemistry; D020543:Proteome; D040901:Proteomics / Q000379:methods*; D001620:beta-Thromboglobulin
chemical_list: C483024:CCL5 protein, human; D018946:Chemokine CCL5; D019742:Chemokines, CC; D039661:Integrin beta3; D019007:P-Selectin; C064936:PF4V1 protein, human; C061615:PPBP protein, human; D010455:Peptides; D019038:Platelet Glycoprotein GPIb-IX Complex; D010980:Platelet Membrane Glycoproteins; D020543:Proteome; D001620:beta-Thromboglobulin; C032193:glycoprotein receptor GPIb-IX; D010978:Platelet Factor 4