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bioRxiv · 10.64898/2026.05.13.724989

Orai1 is required for Ca2+-dependent plasma membrane repair and mechanoadaptation

Abstract

Ca2+-dependent repair of plasma membrane breaches is essential for animal cell viability. An initial passive influx of extracellular Ca2+ triggers the formation of a protein plug that rapidly seals breaches. However, the mechanism of extracellular Ca2+ requirement for subsequent repair remains undefined. EHD2 protein stabilizes the plasma membrane caveolae, which sustain membrane repair, and maintains high surface levels of the caveolae-resident Ca2+ channel Orai1. We establish the requirement of both Orai1 and EHD2 for repair of plasma membrane lesions induced by mechanical injury or by a model bacterial pore-forming toxin. We demonstrate rapid EHD2 recruitment and Orai1-mediated Ca2+ entry at plasma membrane sites of localized mechanical stimulus, the latter requiring EHD2 and CAV1. EHD2 and Orai1 are necessary for mechanosensitive YAP/TAZ-TEAD activation and positive feedback for CAV1 expression that promotes membrane repair. Our studies establish EHD2 and Orai1 as novel components of mammalian plasma membrane repair and mechanoadaptation.

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BibTeXRIS

Luan, H., Cerci, A., Bielecki, T. A., Mohapatra, B. C., Shrestha, S., Wu, W., Storck, M. D., Smith, L. M., Stauderman, K. A., Coulter, D. W., Kotwal, A., Dong, J., Lim, J. Y., Band, V., Ramanathan, S. P., Band, H.. 2026-05-15. Orai1 is required for Ca2+-dependent plasma membrane repair and mechanoadaptation. https://doi.org/10.64898/2026.05.13.724989

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