Project description:As a core Autophagy-related (Atg) protein during yeast autophagy, Atg1 interacts with numerous other proteins, and its kinase activity facilitates to phosphorylate various substrates. How Atg1-interacting partners and substrates synergistically orchestrate autophagy remains to be further dissected. In this study, we conducted a transcriptomic, proteomic and phosphoproteomic profiling of Atg1-dependent molecular landscapes during nitrogen starvation-triggered autophagy.
Project description:In order to asses yeast EC1118® strain expression changes during wine alcoholic fermentation triggered by various nutrient starvations, this experiment describes the gene expression under micronutrient starvations that lead to yeast cell death (oleic acid starvation, ergosterol starvation, pantothenic acid starvation and nicotinic starvation) or allow the maintenance of yeast viability (nitrogen starvation).
Project description:Autophagy as a conserved degradation and recycling machinery is important in normal development and physiology, and defects in this process are linked to many kinds of disease. Because too much or too little autophagy can be detrimental, the process must be tightly regulated both temporally and in magnitude. The transcriptional induction and repression of the autophagy-related (ATG) genes is one crucial aspect of this regulation, but the transcriptional regulators that modulate autophagy are not well characterized. In this study, we identified Pho23 as a master transcriptional repressor for autophagy, with transcriptome profiling revealing that ATG9 is one of the key target genes. Physiological studies with a PHO23 null mutant, or with strains expressing modulated levels of Atg9, demonstrate a critical role of this protein as a regulator of autophagosome formation frequency; Atg9 protein levels correlate with the number of autophagosomes generated upon autophagy induction, and the level of autophagy activity. WT yeast and pho23 deletion mutants were grown under nutrient rich or nitrogen starvation conditions; gene expression was quantified across these 4 samples.
Project description:In Saccharomyces cerevisiae, Atg9 is an important AuTophaGy-related (Atg) protein, plays critical roles in regulating macroautophagy/autophagy, and physically interacts with hundreds of proteins. How Atg9 interacting partners are synergistically orchestrated in autophagy are unclear. Here, we conducted a transcriptomic and proteomic profiling of Atg9-dependent molecular landscapes during nitrogen starvation-induced autophagy.
Project description:In the project «Phosphoproteomics of yeast strains undergoing nitrogen or phosphate starvation» phosphoproteomics and expression proteomics were performed. In biological triplicates label-free quantification of different S. cerevisiae strains was performed. Five strains were used:(a) Ctrl WT, (b) WT, (c) deltaAtg13, (d) deltaPho81, (e) deltaAtg13, deltaPho81 (DKO)
Project description:Autophagy is a conserved process that recycles cellular contents to promote survival. Although nitrogen starvation is the canonical inducer of autophagy, recent studies have revealed several other nutrients important to this process. In this study, we used a quantitative, high-throughput assay to identify potassium starvation as a new and potent inducer of autophagy. We found that potassium-dependent autophagy requires the core pathway kinases Atg1, Atg5, Vps34, as well as other components of Phosphatidylinositol 3-kinase Complex I. Transmission electron microscopy revealed abundant autophagosome formation in response to both stimuli. RNA sequencing indicated distinct transcriptional responses – nitrogen affects transport of ions such as copper while potassium targets the organization of other cellular components. Thus, nitrogen and potassium share the ability to influence metabolic supply and demand but do so in different ways. Both inputs promote catabolism through bulk autophagy, but inhibit cellular anabolism through distinct mechanisms.
Project description:Autophagy is an essential cellular process in eukaryotes that degrades and recycles macromolecules and organelles. Defects in autophagy is known to affect metabolism, including the lipidome. Genetic approaches have identified a series of AuTophaGy-related (ATG) genes in Arabidopsis. In this study we used WT (ecotype Col-0) and two Arabidopsis autophagy-defective mutants, atg7 and atg9 to perform a multi-omics study on the effect of nitrogen starvation treatment, which induces autophagy. Specifically, we have quantified ~100 lipids from leaf and root tissues of WT, atg7 and atg9 mutant plants, under either autophagy-inducing conditions (-N) or normal nitrogen conditions (+N). The lipid species we quantified include: DGDG, MGDG, LPC, LPE, PE, LPG, PC, PA, PG, PI, and PS. Our study sheds lights on the understanding of the relationships between autophagy and metabolism, especially lipid metabolism.
Project description:Transcriptomic analysis of wild type C. albicans and a HIR1 gene deletion mutant during nutrient rich growth (YPD) and upon the shift to nitrogen starvation in yeast carbon base medium supplemented with BSA (YCB-BSA medium).
