Proteomics of phosphorylation and protein dynamics during fertilization and meiotic exit in theegg.

TitleProteomics of phosphorylation and protein dynamics during fertilization and meiotic exit in theegg.
Publication TypeJournal Article
Year of Publication2017
AuthorsPresler, M, Van Itallie, E, Klein, AM, Kunz, R, Coughlin, ML, Peshkin, L, Gygi, SP, Wühr, M, Kirschner, MW
JournalProc Natl Acad Sci U S A
Volume114
Issue50
PaginationE10838-E10847
Date Published2017 Dec 12
ISSN1091-6490
Abstract

Fertilization releases the meiotic arrest and initiates the events that prepare the egg for the ensuing developmental program. Protein degradation and phosphorylation are known to regulate protein activity during this process. However, the full extent of protein loss and phosphoregulation is still unknown. We examined absolute protein and phosphosite dynamics of the fertilization response by mass spectrometry-based proteomics in electroactivated eggs. To do this, we developed an approach for calculating the stoichiometry of phosphosites from multiplexed proteomics that is compatible with dynamic, stable, and multisite phosphorylation. Overall, the data suggest that degradation is limited to a few low-abundance proteins. However, this degradation promotes extensive dephosphorylation that occurs over a wide range of abundances during meiotic exit. We also show that eggs release a large amount of protein into the medium just after fertilization, most likely related to the blocks to polyspermy. Concomitantly, there is a substantial increase in phosphorylation likely tied to calcium-activated kinases. We identify putative degradation targets and components of the slow block to polyspermy. The analytical approaches demonstrated here are broadly applicable to studies of dynamic biological systems.

DOI10.1073/pnas.1709207114
Alternate JournalProc. Natl. Acad. Sci. U.S.A.
PubMed ID29183978
PubMed Central IDPMC5740657
Grant ListR01 HD091846 / HD / NICHD NIH HHS / United States
R01 HD073104 / HD / NICHD NIH HHS / United States
R01 GM039565 / GM / NIGMS NIH HHS / United States
R37 GM039565 / GM / NIGMS NIH HHS / United States
R01 GM103785 / GM / NIGMS NIH HHS / United States