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bioRxiv · 10.1101/2024.09.22.614381

Unsaturated lipids as key control points for caveola formation and disassembly

Abstract

Caveolae are specialized plasma membrane domains with a unique lipid composition. Recent work has implicated lipid peroxidation in triggering caveola disassembly, releasing caveolar proteins to regulate the cellular response to oxidative stress. Here we investigated the role of specific lipid species in caveola formation and response to oxidative stress. Systematic screening of lipid enzymes identified ACSL4, a critical enzyme in the synthesis of polyunsaturated fatty acid-containing lipids, and enzymes involved in the biosynthesis of pro-ferroptotic ether lipids, as key regulators of caveola formation. Omega-6 fatty acids promoted efficient caveola formation, while their oxidation or displacement by omega-3 or monounsaturated fatty acids disrupted this process. Moreover, we found that omega-6 fatty acid-containing membrane lipids were required for oxidative stress-induced caveola disassembly. These findings unveil a new model for caveola formation, highlighting specific unsaturated lipids as essential caveolar components and key control points for caveola disassembly in response to an oxidizing environment.

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Wu, Y., Lim, Y.-W., McMahon, K.-A., Martel, N., Rae, J., Lo, H., Gao, Y., Tillu, V., Larsson, E., Lundmark, R., Levic, D. S., Bagnat, M., Lim, J., Fairlie, D. P., Pol, A., Collins, B., Ariotti, N., Hall, T. E., Parton, R. G.. 2024-09-23. Unsaturated lipids as key control points for caveola formation and disassembly. https://doi.org/10.1101/2024.09.22.614381

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