Selective dephosphorylation by PP2A-B55 directs the meiosis I-meiosis II transition in oocytes
Name
elife-70588-v2.pdf
Description
Published version
Size
7.12 MB
Format
Adobe PDF
Checksum (MD5)
aedf98d4362aa066d7356f3cc8262378
Author(s)
Swartz, S Zachary
Nguyen, Hieu T
McEwan, Brennan C
Adamo, Mark E
Cheeseman, Iain M
Kettenbach, Arminja N
Date Issued
2021
Journal
eLife
Publisher
eLife Sciences Publications, Ltd
Citation
Swartz, S Zachary, Nguyen, Hieu T, McEwan, Brennan C, Adamo, Mark E, Cheeseman, Iain M et al. 2021. "Selective dephosphorylation by PP2A-B55 directs the meiosis I-meiosis II transition in oocytes." eLife, 10.
Version
Final published version
Abstract
Meiosis is a specialized cell cycle that requires sequential changes to the cell division machinery to facilitate changing functions. To define the mechanisms that enable the oocyte-to-embryo transition, we performed time-course proteomics in synchronized sea star oocytes from prophase I through the first embryonic cleavage. Although we found that protein levels were broadly stable, our analysis reveals that dynamic waves of phosphorylation underlie each meiotic stage. We found that the phosphatase PP2A-B55 is reactivated at the meiosis I/meiosis II (MI/MII) transition, resulting in the preferential dephosphorylation of threonine residues. Selective dephosphorylation is critical for directing the MI/MII transition as altering PP2A-B55 substrate preferences disrupts key cell cycle events after MI. In addition, threonine to serine substitution of a conserved phosphorylation site in the substrate INCENP prevents its relocalization at anaphase I. Thus, through its inherent phospho-threonine preference, PP2A-B55 imposes specific phosphoregulated behaviors that distinguish the two meiotic divisions.
MIT Department
Massachusetts Institute of Technology. Department of Biology
Terms of Use
Creative Commons Attribution 4.0 International license
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.7554/ELIFE.70588
