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The PP1 phosphatase complex coordinates pre-mRNA 3’end processing and termination of RNA polymerase II transcription

ABSTRACT: Native affinity purifications of V5-tagged Symplekin (Pta1) from Schizosaccharomyces pombe were analysed by label-free quantitative mass spectrometry to determine how the DPR motif of Symplekin contributes to assembly of the cleavage and polyadenylation (CPA/CPF) machinery with the PP1-PNUTS-WDR82 (PPW) phosphatase complex. Three samples were compared: an untagged mock control, wild-type Symplekin, and a Symplekin DPR-AAA motif mutant. Wild-type Symplekin co-purified with the entire CPF complex including PNUTS, WDR82 and PP1, whereas the DPR-AAA mutant retained interactions with the remainder of CPF but lost association with the PPW complex, demonstrating that the DPR motif mediates recruitment of the PP1 phosphatase module to the 3' end processing machinery.

INSTRUMENT(S):

ORGANISM(S): Schizosaccharomyces Pombe

SUBMITTER: Luke Slade

LAB HEAD: Lidia Vasilieva

PROVIDER: PXD081924 | Pride | 2026-07-31

REPOSITORIES: Pride

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			Action	DRS
	2025-07-18-decoys-reviewed-contam-UP000002485.fas	Other
	Mock_filter.log	Other
	Mock_ion.tsv	Tabular
	Mock_peptide.tsv	Tabular
	Mock_protein.fas	Other

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