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

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 contracts and is disassembled by Vps4 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.

Mechanochemical Rules for Shape-Shifting Filaments that Remodel Membranes

“…Additionally, although monomers of different types share a similar molecular structure [2,5], polymers of different ESCRT-III monomers have been observed to have different shapes and different membrane binding interfaces, depending on their precise monomer composition [5,[12][13][14][15][16][17]. Therefore, as the copolymers change in composition, their geometry and mechanical properties are also expected to change, allowing the ESCRT-III to perform work on the membrane [8,[18][19][20][21]. The time ordering of this staged assembly-disassembly process is robust and is believed to progressively drive membrane deformation and scission in a variety of biological processes [9,17,18,22,23].…”

“…PHYSICAL REVIEW LETTERS 129, 268101 (2022) 268101-4 active energy supply; whereas in experiments, dynamic disassembly is only observed upon addition of ATPase Vps4, which unfolds monomers and extracts them from the filament [9,10,20,[30][31][32][33][34]. This led us to explore whether a Vps4-like activity that promotes stress-dependent polymer disassembly could aid the process.…”

Automated STED nanoscopy for high-throughput imaging of cellular structures

“…To further minimise photodamage, adapted acquisition schemes such as ResCUE 13 and DyMIN 14 can be applied. In our study, all selected objects were measured within a FOV of 2.5×2.5µm 2 , using a pixel size of 17×17nm 2 , while we obtained a resolution of around 30nm 15 (Fig. 7).…”

“…The archaea samples used for imaging in this work were prepared as described in Hurtig et al 15 . DNA was labelled with Hoechst and imaged in the 405nm channel.…”

Insights into the function of ESCRT and its role in enveloped virus infection

“…It mediates the rupture and sealing of various cellular membranes, including those between the nuclear envelope and plasma membrane, and is released from the membrane in the final stage through the transient ATP-dependent reaction with other ESCRT proteins, facilitated by Vps4. Furthermore, several studies have shown that the ESCRT-III complex plays important roles in various biological processes, including cell division (Harker-Kirschneck et al, 2022;Hurtig et al, 2023), immune regulation (Li et al, 2022), and neurodegenerative diseases (Lee et al, 2007a;Han et al, 2012).…”