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Identification of PP1-fusion phosphatase substrates

ABSTRACT: This experiments was designed to identify substrates of holophosphatase complexes of PP1 and its specificity-determining regulator proteins. We generated fusions of Flag-tagged Protein Phosphatase 1 fusions with Phactr1-4, Neurabin, Spinophilin, PPPR15A, PPP1R15B, and PNUTS, in each case including known protein interaction domains immediately C-terminal to the PP1-binding sequences. Each fusion protein was stably expressed in 293 Flp-In TRex cells using a tetracycline inducible vector. To investigate the substrate specificities of the PP1-fusion proteins, we performed Tandem-Mass-Tag (TMT) phosphoproteomics. Fractionated peptides were measured in both MS2 and MS3 modes for maximal identification and quantification. Expression of the PP1-fusions revealed numerous phosphorylation sites that were specifically depleted compared with cells expressing PP1 alone.

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Permanent Cell Line Cell

SUBMITTER: Roman Fedoryshchak

LAB HEAD: Richard Treisman

PROVIDER: PXD055166 | Pride | 2025-05-28

REPOSITORIES: Pride

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			Action	DRS
	TRA9941A40RW20_A1.raw	Raw
	TRA9941A40RW21_A1.raw	Raw
	TRA9941A40RW22_A2.raw	Raw
	TRA9941A40RW23_A2.raw	Raw
	TRA9941A40RW24_A3.raw	Raw

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