The yeast high-affinity glucose transporters Hxt6p and Hxt7p are rapidly degraded during nitrogen starvation in the presence of high concentrations of fermentable carbon sources. Our results suggest that degradation is mainly due to the stimulation of general protein turnover and not caused by a mechanism specifically triggered by glucose. Analysis of Hxt6p/7p stability and cellular distribution in end4, aut2 and apg1 mutants indicates that Hxt7p is internalized by endocytosis, and autophagy is involved in the final delivery of Hxt7p to the vacuole for proteolytic degradation. Internalization and degradation of Hxt7p were blocked after truncation of its N-terminal hydrophilic domain. Nevertheless, this fully functional and stabilized hexose transporter could not maintain fermentation capacity of the yeast cells under starvation conditions, indicating a regulatory constraint on glucose uptake.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Annotation Extension||Reference|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Assay||Construct||Conditions||Strain Background||Reference|