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bioRxiv · 10.1101/2024.09.10.612341

Mechanism of Actin Filament Severing and Capping by Gelsolin

Barrie, K. R.·Rebowski, G.·Dominguez, R.
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Abstract

Gelsolin is the prototypical member of a family of Ca2+-dependent F-actin severing and capping proteins. A structure of Ca2+-bound full-length gelsolin at the barbed end shows domains G1G6 and the inter-domain linkers wrapping around F-actin. Another structure shows domains G1G3, a fragment produced during apoptosis, on both sides of F-actin. Conformational changes that trigger severing occur on one side of F-actin with G1G6 and on both sides with G1G3. Gelsolin remains bound after severing, blocking subunit exchange.

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Barrie, K. R., Rebowski, G., Dominguez, R.. 2024-09-10. Mechanism of Actin Filament Severing and Capping by Gelsolin. https://doi.org/10.1101/2024.09.10.612341

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