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bioRxiv · 10.1101/2022.09.16.508273

The patterned assembly and stepwise Vps4-mediated disassembly of composite ESCRT-III polymers drives archaeal cell division

Hurtig, F.·Burgers, T. C. Q.·Cezanne, A.·Jiang, X.·Mol, F. N.·Traparic, J.·Tarrason Risa, G.·Arashiro Pulschen, A.·Harker-Kirschneck, L.·Saric, A.·Vlijm, R.·Baum, B.
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Abstract

ESCRT-III family proteins form composite polymers that deform and cut membrane tubes in the context of a wide range of cell biological processes across the tree of life. In reconstituted systems sequential changes in the composition of ESCRT-III polymers induced by the AAA ATPase Vps4 have been shown to remodel membranes. However, it is not known how composite ESCRT-III polymers are organised and remodelled in space and time in cells. Here, taking advantage of the relative simplicity of the ESCRT-III-dependent division system in Sulfolobus acidocaldarius, one of the closest experimentally tractable prokaryotic relative of eukaryotes, we use super-resolution microscopy and computational modelling to show how CdvB/CdvB1/CdvB2 proteins form a precisely patterned composite ESCRT-III division ring which undergoes stepwise Vps4-dependent disassembly and contracts to cut cells into two. These observations lead us to suggest sequential changes in a patterned composite polymer as a general mechanism of ESCRT-III-dependent membrane remodelling.

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Hurtig, F., Burgers, T. C. Q., Cezanne, A., Jiang, X., Mol, F. N., Traparic, J., Tarrason Risa, G., Arashiro Pulschen, A., Harker-Kirschneck, L., Saric, A., Vlijm, R., Baum, B.. 2022-09-16. The patterned assembly and stepwise Vps4-mediated disassembly of composite ESCRT-III polymers drives archaeal cell division. https://doi.org/10.1101/2022.09.16.508273

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