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Cryo Electron Microscopy of CHMP1B/IST1 Membrane-Bound Filaments with Brominated Lipid Probes

ABSTRACT:

SUBMITTER: Frank Russell Moss

PROVIDER: EMPIAR-11277 | biostudies-other |

REPOSITORIES: biostudies-other

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Brominated lipid probes expose structural asymmetries in constricted membranes.

Moss Frank R FR Lincoff James J Tucker Maxwell M Mohammed Arshad A Grabe Michael M Frost Adam A

Nature structural & molecular biology 20230109 2

Lipids in biological membranes are thought to be functionally organized, but few experimental tools can probe nanoscale membrane structure. Using brominated lipids as contrast probes for cryo-EM and a model ESCRT-III membrane-remodeling system composed of human CHMP1B and IST1, we observed leaflet-level and protein-localized structural lipid patterns within highly constricted and thinned membrane nanotubes. These nanotubes differed markedly from protein-free, flat bilayers in leaflet thickness, ...[more]

PMID: 36624348

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