PXD042194

PXD042194 is an original dataset announced via ProteomeXchange.

Title	Distinct dephosphorylation site signatures of PP1 and PP2A-B55 coordinate mitotic exit.
Description	Mitotic exit requires extensive dephosphorylation of Ser/Thr residues by the PP1 and PP2A-B55 protein phosphatases in human cells. Several aspects of this are poorly understood including specific substrates and determinants of phosphatase specificity. Here we develop a novel in vitro assay, MRBLE-dephos, that allows multiplexing of dephosphorylation reactions to determine phosphatase specificity. Using MRBLE-dephos, we establish amino acid preferences of the residues surrounding the phosphorylation site for PP1 and PP2A-B55, which reveals common and unique preferences for the two phosphatases. We use specific inhibition of PP1 and PP2A-B55 in mitotic exit lysates coupled with quantitative phosphoproteomics to identify more than 2000 regulated phosphorylation sites and integrate this with mitotic interactomes to obtain a comprehensive map of mitotic dephosphorylation events. Importantly, the sites dephosphorylated during mitotic exit reveal key signatures that are consistent with the MRBLE-dephos results. We use these insights to specifically alter INCENP dephosphorylation kinetics at mitotic exit resulting in defective cytokinesis underscoring the biological relevance of our determined specificity principles. Finally, we provide a comprehensive characterization of PP1 binding motifs and show how these can shape dephosphorylation and how PP1 primes its own association with these motifs at mitotic exit. Collectively we provide a framework for understanding mitotic exit regulation by dephosphorylation and novel approaches to dissect protein phosphatase specificity.
HostingRepository	MassIVE
AnnounceDate	2023-09-05
AnnouncementXML	Submission_2023-09-05_07:02:38.832.xml
DigitalObjectIdentifier
ReviewLevel	Non peer-reviewed dataset
DatasetOrigin	Original dataset
RepositorySupport	Supported dataset by repository
PrimarySubmitter	Mark Adamo
SpeciesList	scientific name: Homo sapiens; common name: human; NCBI TaxID: 9606;
ModificationList	Oxidation; Carbamidomethyl; Phospho; TMT6plex
Instrument	Q Exactive Plus; Orbitrap Fusion

Revision	Datetime	Status	ChangeLog Entry
0	2023-05-12 10:12:44	ID requested
⏵ 1	2023-09-05 07:02:39	announced

no publication

submitter keyword: PP1, PP2A-B55, mitosis, mitotic exit, MRBLE-dephos, phosphatase, phosphoproteomics, INCENP, cytokinesis, dephosphorylation

Arminja Kettenbach
contact affiliation	The Geisel School of Medicine at Dartmouth
contact email	arminja.n.kettenbach@dartmouth.edu
lab head
Mark Adamo
contact affiliation	Dartmouth College
contact email	mark.e.adamo@dartmouth.edu
dataset submitter

MassIVE dataset URI

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