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bioRxiv · 10.1101/2021.06.09.447684

Caveolae, CAVIN1, and lipid peroxidation mediate the oxidative stress response

Abstract

Caveolae have been linked to many biological functions, but their precise roles are unclear. Using quantitative whole cell proteomics of genome-edited cells, we show that the oxidative stress response is the major pathway dysregulated in cells lacking the key caveola structural protein, CAVIN1. CAVIN1 deletion compromised sensitivity to oxidative stress in cultured cells and in animals. Wound-induced accumulation of reactive oxygen species and apoptosis were suppressed in Cavin1-null zebrafish, negatively affecting regeneration. Oxidative stress triggered lipid peroxidation and induced caveolar disassembly. The resulting release of CAVIN1 from caveolae allowed direct interaction between CAVIN1 and NRF2, a key regulator of the antioxidant response, facilitating NRF2 degradation. CAVIN1-null cells with impaired negative regulation of NRF2 showed resistance to lipid peroxidation-induced ferroptosis. Thus, caveolae, via lipid peroxidation and CAVIN1 release, maintain cellular susceptibility to oxidative stress-induced cell death demonstrating a crucial role for this enigmatic organelle in cellular homeostasis and wound response.

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BibTeXRIS

Wu, Y., Lim, Y.-W., Stroud, D. A., Martel, N., Hall, T. E., Lo, H., Ferguson, C., Ryan, M. T., McMahon, K.-A., Parton, R. G.. 2021-06-09. Caveolae, CAVIN1, and lipid peroxidation mediate the oxidative stress response. https://doi.org/10.1101/2021.06.09.447684

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