Mierzwa BE, Chiaruttini N, Redondo-Morata L, von Filseck JM, Konig J, Larios J, Poser I, Muller-Reichert T, Scheuring S, Roux A, Gerlich DW.
Nat Cell Biol 2017; 19: 787.
he endosomal sorting complex required for transport (ESCRT)-III mediates membrane fission in fundamental cellular processes, including cytokinesis. ESCRT-III is thought to form persistent filaments that over time increase their curvature to constrict membranes. Unexpectedly, we found that ESCRT-III at the midbody of human cells rapidly turns over subunits with cytoplasmic pools while gradually forming larger assemblies. ESCRT-III turnover depended on the ATPase VPS4, which accumulated at the midbody simultaneously with ESCRT-III subunits, and was required for assembly of functional ESCRT-III structures. In vitro, the Vps2/Vps24 subunits of ESCRT-III formed side-by-side filaments with Snf7 and inhibited further polymerization, but the growth inhibition was alleviated by the addition of Vps4 and ATP. High-speed atomic force microscopy further revealed highly dynamic arrays of growing and shrinking ESCRT-III spirals in the presence of Vps4. Continuous ESCRT-III remodelling by subunit turnover might facilitate shape adaptions to variable membrane geometries, with broad implications for diverse cellular processes.
PubMed: 28604678. Doi: 10.1038/ncb3559.
Extra Video Data: Dynamics of ESCRT-III spirals.