Dataset Information

Characterization of Ksg1 protein kinase-dependent phosphoproteome in the fission yeast S. pombe

ABSTRACT: Ksg1 is an essential protein kinase of the fission yeast S. pombe that belongs to the AGC kinase family and is homologous to the mammalian PDPK1 kinase. Previous studies have shown that Ksg1 functions in the nutrient-sensing TOR signaling pathway and is involved in the phosphorylation and activation of other AGC kinases, thereby affecting various downstream targets related to metabolism, cell division, stress response, and gene expression. To date, the molecular function of Ksg1 has been analyzed using its temperature sensitive mutants or mutants expressing its truncated isoforms, which are not always suitable for functional studies of Ksg1 and the identification of its targets. To overcome these limitations, we employed a chemical genetic strategy and used a conditional ksg1as mutant sensitive to an ATP analog. Combining this mutant with quantitative phosphoproteomics analysis, we identified 1986 phosphosites that were differentially phosphorylated when Ksg1as kinase was inhibited by an ATP analog. We found that proteins whose phosphorylation was dysregulated after inhibition of Ksg1as kinase were mainly represented by those involved in the regulation of cytokinesis, contractile ring contraction, cell division, septation initiation signaling cascade, intracellular protein kinase cascade, barrier septum formation, protein phosphorylation, intracellular signal transduction, cytoskeleton organization, cellular response to stimulus, or in RNA, ncRNA and rRNA processing. Importantly, proteins with significantly down-regulated phosphorylation were specifically enriched for R-X-X-S and R-X-R-X-X-S motifs, which are typical consensus substrate sequences for phosphorylation by the AGC family of kinases. The results of this study provide a basis for further analysis of the role of the Ksg1 kinase and its targets in S. pombe and may also be useful for studying Ksg1 orthologs in other organisms.

INSTRUMENT(S): Orbitrap Exploris 480

ORGANISM(S): Schizosaccharomyces Pombe

SUBMITTER: Peter Barath

LAB HEAD: Peter Barath

PROVIDER: PXD054277 | Pride | 2024-11-02

REPOSITORIES: Pride

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			Action	DRS
	20231025_50cmColumn_139min_Ksg1_TMT_FR1_metoda21_01.raw	Raw
	20231025_50cmColumn_139min_Ksg1_TMT_FR2_metoda21_01.raw	Raw
	20231025_50cmColumn_139min_Ksg1_TMT_FR3_metoda21_02.raw	Raw
	20231025_50cmColumn_139min_Ksg1_TMT_FR4_metoda21_02.raw	Raw
	20231025_50cmColumn_139min_Ksg1_TMT_FR5_metoda21_02.raw	Raw

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Characterization of Ksg1 protein kinase-dependent phosphoproteome in the fission yeast S. pombe.

Cipak Lubos L Sivakova Barbara B Bellova Jana J Danchenko Maksym M Jurcik Jan J Cipakova Ingrid I Lalakova Laura Olivia LO Gregan Juraj J Barath Peter P

Biochemical and biophysical research communications 20241025

Ksg1 is an essential protein kinase of the fission yeast S. pombe that belongs to the AGC kinase family and is homologous to the mammalian PDPK1 kinase. Previous studies have shown that Ksg1 functions in the nutrient-sensing TOR signaling pathway and is involved in the phosphorylation and activation of other AGC kinases, thereby affecting various downstream targets related to metabolism, cell division, stress response, and gene expression. To date, the molecular function of Ksg1 has been analyze ...[more]

PMID: 39476757

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