Biophysical Society Thematic Meeting| Padova 2019

Quantitative Aspects of Membrane Fusion and Fission

Poster Abstracts

45-POS Board 45 ESCRT-MEDIATED REMODELLING AND SEVERING OF PULLED MEMBRANE NANOTUBES Mark Remec Pavlin 2 ; Jamie Shiah 1 ; James Hurley 1,2,3 ; 1 UC Berkeley , Molecular and Cell Biology, Berkeley, California, USA 2 UC Berkeley, Graduate Group in Biophysics , Berkeley, California, USA 3 Lawrence Berkeley National Laboratory, Molecular Biophysics and Integrated Bioimaging, Berkeley, California, USA The endosomal sorting complex required for transport (ESCRTs) constitute an evolutionarily conserved set of proteins that have been identified as crucial for many membrane remodeling and membrane scission events in eukaryotes. Notably, structural work has characterized a variety of polymers formed by these proteins, including spirals, rings, cones and tubes that can deform membranes in vivo and in vitro. Here, we utilize a home-built optical trap and confocal fluorescence microscopy setup to functionally characterize the behavior of ESCRT proteins on membrane nanotubes. We show that ESCRTs are capable of nucleating onto, applying force onto, and eventually severing membrane nanotubes. Fluorescence imaging and force measurement of this process provide deeper mechanistic insight into the molecular function of ESCRT proteins as they remodel and sever membranes.

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