EGFR dynamics on CHO–K1 cells with depletion and supplementation of cholesterol
Identifier: 439-Takayama-dynamicsEGFR
Published: 2025-11-28 Licence: CC BY 4.0 Publisher: SSBD:database
Epidermal growth factor receptor (EGFR)-mediated signal transduction controls cell growth and proliferation. The signaling pathway is regulated so that it is activated only by external EGF stimuli, but the mechanisms that prevent EGF-independent spontaneous activation of EGFR-mediated signaling are unknown. Here the authors report cholesterol depletion activates EGFR-mediated signaling without EGF. They applied automated single-molecule imaging to EGFR and characterized the lateral diffusion and cluster formation on cholesterol-depleted and cholesterol-supplemented membranes. In cells in which cholesterol was depleted by methyl-beta-cyclodextrin treatment, EGFR exhibited a reduction in lateral diffusion, an acceleration of cluster formation, and autophosphorylation without EGF. Concurrently, extracellular signal-regulated kinase (ERK), which is regulated by EGFR-mediated signaling, exhibited phosphorylation and nuclear translocation without EGF. These cholesterol depletion-induced changes were similar, albeit less efficient, to those that occurred with EGF stimulation in normal cells without methyl-beta-cyclodextrin, indicating the spontaneous activation of EGFR signaling. The exogenous supplementation of cholesterol suppressed the methyl-beta-cyclodextrin-induced spontaneous activation of EGFR and ERK nuclear translocation. Single-molecule imaging of EGFR in a large number of cells revealed cell-to-cell heterogeneity, with a sub-population showing a high ability for spontaneous activation. These results provide evidence that EGFR-mediated signaling is properly regulated by cholesterol metabolism to prevent uncontrolled spontaneous activation.
Imaging Methods: recorded image evanescent wave microscopy
Organisms: Cricetulus griseus