A bridge from the endoplasmic reticulum to the plasma membrane comes into view.
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ABSTRACT:
SUBMITTER: Mahling R
PROVIDER: S-EPMC9169776 | biostudies-literature | 2022 Apr
REPOSITORIES: biostudies-literature
Publications
A bridge from the endoplasmic reticulum to the plasma membrane comes into view.
Mahling Ryan R Ben-Johny Manu M
Proceedings of the National Academy of Sciences of the United States of America 20220330 15
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Project description:Endoplasmic reticulum (ER)-plasma membrane (PM) tethering is crucial for the non-vesicular lipid transport between the ER membrane and the PM. However, the PM-associated ER can impede the PM binding of cytoskeletons and other organelles. It is poorly understood how the competition between the ER and cytoskeletons/organelles on the PM is resolved. Here, we show that, upon septin collar assembly, ER-PM tethering proteins are excluded from the yeast bud sites, and the PM-associated ER is locally detached from the PM. Our results suggest that PM flows by polarized exocytosis extrude PM proteins, including ER-PM tethering proteins, from the bud sites. When the reorganization of the ER-PM tethering was inhibited by exocytosis repression, septin localization was restricted to the PM sites poor in ER-PM tethering proteins. This study proposes machinery reconciling ER-septin competition on the PM, providing mechanistic insights into the spatial organization of PM-associated organelles and cytoskeletons.
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