title: Copy number analysis of the murine platelet proteome spanning the complete abundance range.
abstract: Knowledge of the identity and quantity of expressed proteins of a cell type is a prerequisite for a complete understanding of its molecular functions. Mass-spectrometry-based proteomics has allowed the identification of the entire protein complement of yeast and the close-to-complete set of proteins expressed in mammalian cell lines. Using recent technological advances, we here characterized the proteome of murine platelets, key actors in mediating hemostasis and thrombosis. We accurately measured the absolute protein concentrations of 13 platelet proteins using SILAC-protein epitope signature tags and used them as reference points to estimate the copy numbers of all proteins of the platelet proteome. To distinguish contaminants such as plasma or erythrocyte proteins from true platelet proteins, we monitored protein abundance profiles across multiple purification steps. In total, we absolutely quantified 4,400 platelet proteins, with estimated copy numbers ranging from less than 10 to about a million per cell. Stoichiometries derived from our data correspond well with previous studies. Our study provides a close-to-complete reference map of platelet proteins that will be useful to the community, for instance, for interpreting mouse models of human platelet diseases.
authors.affiliation: From the ‡Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany;
authors.forename: Marlis
authors.initials: M
authors.lastname: Zeiler
authors.affiliation: §Department of Molecular Medicine, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Moser
authors.affiliation: From the ‡Department of Proteomics and Signal Transduction, Max Planck Institute of Biochemistry, Am Klopferspitz 18, D-82152 Martinsried, Germany; mmann@biochem.mpg.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Mann
mesh_terms: D000818:Animals; D001792:Blood Platelets / Q000737:chemistry* / Q000378:metabolism; D015870:Gene Expression; D053858:Metabolic Networks and Pathways / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D020033:Protein Isoforms / Q000302:isolation & purification; D020543:Proteome / Q000302:isolation & purification*; D015398:Signal Transduction
chemical_list: D020033:Protein Isoforms; D020543:Proteome