Glucose deprivation triggers DCAF1-mediated inactivation of Rheb-mTORC1 and promotes cancer cell survival

Cell Death Dis. 2024 Jun 11;15(6):409. doi: 10.1038/s41419-024-06808-1.

Abstract

Low glucose is a common microenvironment for rapidly growing solid tumors, which has developed multiple approaches to survive under glucose deprivation. However, the specific regulatory mechanism remains largely elusive. In this study, we demonstrate that glucose deprivation, while not amino acid or serum starvation, transactivates the expression of DCAF1. This enhances the K48-linked polyubiquitination and proteasome-dependent degradation of Rheb, inhibits mTORC1 activity, induces autophagy, and facilitates cancer cell survival under glucose deprivation conditions. This study identified DCAF1 as a new cellular glucose sensor and uncovered new insights into mechanism of DCAF1-mediated inactivation of Rheb-mTORC1 pathway for promoting cancer cell survival in response to glucose deprivation.

MeSH terms

  • Autophagy
  • Cell Line, Tumor
  • Cell Survival*
  • Glucose* / metabolism
  • HEK293 Cells
  • Humans
  • Mechanistic Target of Rapamycin Complex 1* / metabolism
  • Monomeric GTP-Binding Proteins / genetics
  • Monomeric GTP-Binding Proteins / metabolism
  • Neoplasms / genetics
  • Neoplasms / metabolism
  • Neoplasms / pathology
  • Proteasome Endopeptidase Complex / metabolism
  • Ras Homolog Enriched in Brain Protein* / genetics
  • Ras Homolog Enriched in Brain Protein* / metabolism
  • Signal Transduction
  • Ubiquitin-Protein Ligases / genetics
  • Ubiquitin-Protein Ligases / metabolism
  • Ubiquitination

Substances

  • Mechanistic Target of Rapamycin Complex 1
  • Ras Homolog Enriched in Brain Protein
  • Glucose
  • RHEB protein, human
  • RRAGD protein, human
  • Proteasome Endopeptidase Complex
  • Monomeric GTP-Binding Proteins
  • Ubiquitin-Protein Ligases