Authors:

Research Videos ( author1@researchvideos.net )

Abstract :

To coordinate cellular physiology, eukaryotic cells rely on the rapid exchange of molecules at specialized organelle-organelle contact sitesHere we combine three-dimensional electron microscopy with high-speed molecular tracking of a model organelle tether, Vesicle-associated membrane protein (VAMP)-associated protein B (VAPB), to map the structure and diffusion landscape of ERMCSs. We uncovered dynamic subdomains within VAPB contact sites that correlate with ER membrane curvature and undergo rapid remodelling. We show that VAPB molecules enter and leave ERMCSs within seconds, despite the contact site itself remaining stable over much longer time scales. This metastability allows ERMCSs to remodel with changes in the physiological environment to accommodate metabolic needs of the cell. These results establish high-speed single-molecule imaging as a new tool for mapping the structure of contact site interfaces and reveal that the diffusion landscape of VAPB at contact sites is a crucial component of ERMCS homeostasis.

Keywords :

["cellular biology","VAPB molecules","single-molecule imaging","Endoplasmicreticulum","membrane protein"]

Disciplines :

Biology and Life Sciences

Subdisciplines :

Cell Biology, Molecular Biology, Neuroscience

Video Type :

2D

Publishing Licence :

Open-access

Submitted On :

2024/04/14

References :

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