title: Phosphoproteomic network analysis in the sea urchin Strongylocentrotus purpuratus reveals new candidates in egg activation.
abstract: Fertilization triggers a dynamic symphony of molecular transformations induced by a rapid rise in intracellular calcium. Most prominent are surface alterations, metabolic activation, cytoskeletal reorganization, and cell-cycle reentry. While the activation process appears to be broadly evolutionarily conserved, and protein phosphorylation is known to play a key role, the signaling networks mediating the response to fertilization are not well described. To address this gap, we performed a time course phosphoproteomic analysis of egg activation in the sea urchin Strongylocentrotus purpuratus, a system that offers biochemical tractability coupled with exquisite synchronicity. By coupling large-scale phosphopeptide enrichment with unbiased quantitative MS, we identified striking changes in global phosphoprotein patterns at 2- and 5-min postfertilization as compared to unfertilized eggs. Overall, we mapped 8796 distinct phosphosite modifications on 2833 phosphoproteins, of which 15% were differentially regulated in early egg activation. Activated kinases were identified by phosphosite mapping, while enrichment analyses revealed conserved signaling cascades not previously associated with egg activation. This work represents the most comprehensive study of signaling associated with egg activation to date, suggesting novel mechanisms that can be experimentally tested and providing a valuable resource for the broader research community. All MS data have been deposited in the ProteomeXchange with identifier PXD002239 (http://proteomecentral.proteomexchange.org/dataset/PXD002239).
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Hongbo
authors.initials: H
authors.lastname: Guo
authors.affiliation: Department of Ecology, Evolution and Marine Biology, UC Santa Barbara, Santa Barbara, CA, USA.
authors.forename: Ana Elisa
authors.initials: AE
authors.lastname: Garcia-Vedrenne
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Ruth
authors.initials: R
authors.lastname: Isserlin
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Lugowski
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, and Marine Science Institute, Santa Barbara, CA, USA.
authors.forename: Anthony
authors.initials: A
authors.lastname: Morada
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, and Marine Science Institute, Santa Barbara, CA, USA.
authors.forename: Alex
authors.initials: A
authors.lastname: Sun
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, and Marine Science Institute, Santa Barbara, CA, USA.
authors.forename: Yishen
authors.initials: Y
authors.lastname: Miao
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Uros
authors.initials: U
authors.lastname: Kuzmanov
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Cuihong
authors.initials: C
authors.lastname: Wan
authors.affiliation: Collaborative Innovation Center of Chinese Medicinal Resources Industrialization, College of Pharmacy, Nanjing University of Chinese Medicine, Nanjing, P. R. China.
authors.forename: Hongyue
authors.initials: H
authors.lastname: Ma
authors.affiliation: Department of Molecular, Cellular and Developmental Biology, and Marine Science Institute, Santa Barbara, CA, USA.
authors.forename: Kathy
authors.initials: K
authors.lastname: Foltz
authors.affiliation: Donnelly Centre for Cellular and Biomolecular Research, University of Toronto, Toronto, ON, Canada.
authors.forename: Andrew
authors.initials: A
authors.lastname: Emili
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism; D040901:Proteomics; D012617:Sea Urchins / Q000378:metabolism*; D047270:Strongylocentrotus purpuratus / Q000378:metabolism*
chemical_list: D002118:Calcium
keywords: Animal proteomics; Calcium; Egg activation; Network analysis; Phosphoproteomics