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bioRxiv · 10.1101/716308

Anisotropic ESCRT-III architecture governs helical membrane tube formation

Moser von Filseck, J.·Barberi, L.·Talledge, N.·Johnson, I.·Frost, A.·Lenz, M.·Roux, A.
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Abstract

ESCRT-III proteins assemble into ubiquitous membrane-remodeling polymers during many cellular processes. Here we describe the structure of helical membrane tubes that are scaffolded by bundled ESCRT-III filaments. Cryo-ET reveals how the shape of the helical membrane tube arises from the assembly of distinct bundles of protein filaments that bind the membrane with different mean curvatures. Cryo-EM reveals how one of these ESCRT-III filaments engages the membrane tube through a novel interface. Mathematical modeling of the helical membrane tube suggests how its shape emerges from differences in membrane binding energy, positional rigidity, and membrane tension. Altogether, our findings support a model in which increasing the rigidity of ESCRT-III filaments through the assembly of multi-strands triggers buckling of the membrane.\n\nOne Sentence SummaryESCRT-III heteropolymers deform membranes into helical tubes.

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Moser von Filseck, J., Barberi, L., Talledge, N., Johnson, I., Frost, A., Lenz, M., Roux, A.. 2019-07-26. Anisotropic ESCRT-III architecture governs helical membrane tube formation. https://doi.org/10.1101/716308

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