Gcn5p and Ubp8p Affect Protein Ubiquitylation and Cell Proliferation by Altering the Fermentative/Respiratory Flux Balance in Saccharomyces cerevisiae

mBio

Michele Saliola¹  Giulia Fanelli²  Veronica De Luca²  Elisabetta Cretella²  Raffaele Antonio Palladino²  Patrizia Filetici²  Valentina Panzeri³  Pierluigi Mauri³  Valentina Roffia³  Antonella De Palma³ 

[1] Department of Biology and Biotechnologies Charles Darwin, Sapienza University of Rome, Rome, Italy;Institute of Molecular Biology and Pathology/CNR, Sapienza University of Rome, Rome, Italy;Proteomics and Metabolomics Unit, Institute for Biomedical Technologies (ITB-CNR), Segrate, Italy;

关键词: ubiquitylation;    Gcn5p;    Ubp8p;    glycolytic flux;    sugar utilization;   

DOI  :  10.1128/mBio.01504-20

来源: DOAJ

【 摘 要 】

ABSTRACT Protein ubiquitylation regulates not only endocellular trafficking and proteasomal degradation but also the catalytic activity of enzymes. In Saccharomyces cerevisiae, we analyzed the composition of the ubiquitylated proteomes in strains lacking acetyltransferase Gcn5p, Ub-protease Ubp8p, or both to understand their involvement in the regulation of protein ubiquitylation. We analyzed His6Ub proteins with a proteomic approach coupling micro-liquid chromatography and tandem mass spectrometry (μLC-MS/MS) in gcn5Δ, ubp8Δ and ubp8Δ gcn5Δ strains. The Ub-proteome altered in the absence of Gcn5p, Ubp8p, or both was characterized, showing that 43% of the proteins was shared in all strains, suggesting their functional relationship. Remarkably, all major glycolytic enzymes showed increased ubiquitylation. Phosphofructokinase 1, the key enzyme of glycolytic flux, showed a higher and altered pattern of ubiquitylation in gcn5Δ and ubp8Δ strains. Severe defects of growth in poor sugar and altered glucose consumption confirmed a direct role of Gcn5p and Ubp8p in affecting the REDOX balance of the cell. IMPORTANCE We propose a study showing a novel role of Gcn5p and Ubp8p in the process of ubiquitylation of the yeast proteome which includes main glycolytic enzymes. Interestingly, in the absence of Gcn5p and Ubp8p glucose consumption and redox balance were altered in yeast. We believe that these results and the role of Gcn5p and Ubp8p in sugar metabolism might open new perspectives of research leading to novel protocols for counteracting the enhanced glycolysis in tumors.

【 授权许可】

Unknown