Extracellular glucose level regulates dependence on GRP78 for cell surface localization of multipass transmembrane proteins in HeLa cells.
Yusuke ToyodaBusra AkarlarMihail SarovNurhan OzluShigeaki SaitohPublished in: FEBS letters (2018)
Many human-cultured cell lines survive glucose starvation, but the underlying mechanisms remain unclear. Here, we searched for proteins required for cellular adaptation to glucose-limited conditions and identified several endoplasmic reticulum chaperones in the glucose-regulated protein (GRP) family as proteins enriched in the cellular membrane. Surprisingly, these proteins, which are required for cell surface localization of GLUT1 under high-glucose conditions, become dispensable for targeting GLUT1 to the surface upon glucose starvation. In marked contrast, cell surface localization of single-pass transmembrane proteins, such as epidermal growth factor receptor and CD98, is not disturbed by GRP78 depletion regardless of the extracellular glucose level. These results indicate that the extracellular glucose level regulates dependence on the GRPs for cell surface localization of multipass transmembrane proteins.
Keyphrases
- cell surface
- blood glucose
- endothelial cells
- epidermal growth factor receptor
- high glucose
- endoplasmic reticulum
- magnetic resonance
- magnetic resonance imaging
- induced apoptosis
- blood pressure
- computed tomography
- endoplasmic reticulum stress
- advanced non small cell lung cancer
- cell cycle arrest
- adipose tissue
- signaling pathway