Dynamic phosphoprotemics yeast nitrogen down-shift

ABSTRACT: To resolve the temporal sequence of phosphorylation events responding to nutritional and chemically induced up and downshifts of TORC1 signaling in S. cerevisiae wildtype, we performed quantitative MS phosphoproteomics upon nitrogen-quality up and downshifts and rapamycin treatment. We generated a high quality dataset byapplying a high resolution sampling, parallel sample processing and a dedicated data analysis pipeline that allowed us to select significant transient dynamics. By exploiting the temporal resolution of our data and the complementary of the shift experiments, we identified early phosphorylation changes regulated directly by TORC1 or by its proximal substrate kinases, and found both established and novel candidate TORC1 targets. Among the candidateTORC1 targets were the metabolic enzymes Amd1, Hom3, Nth1 and Tsl1, involved in nucleotide, amino acid and storage carbohydrate metabolism. Functional assessment of the role of phosphorylation for these and other enzymes was achieved by correlating phosphopeptide with the corresponding enzyme-associated metabolite dynamics. Candidate kinases regulating these enzymes were identified by establishing TORC1-proximity and differential kinase activity criteria. Our work provides first evidence of TORC1-dependent regulation of the metabolic enzymes Amd1and Hom3 by the kinases Sch9 and Atg1, respectively, providing mechanistic insights into on how TORC1 controls nucleotide and amino acid metabolism in response to the quality of the nitrogen source.

INSTRUMENT(S): LTQ Orbitrap

ORGANISM(S): Saccharomyces Cerevisiae (baker's Yeast)

SUBMITTER: Christina Ludwig  

LAB HEAD: Ruedi Aebersold

PROVIDER: PXD000939 | Pride | 2022-02-22

REPOSITORIES: Pride