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LDL Cholesterol Uptake Assay Using Live Cell Imaging Analysis with Cell Health Monitoring
Published on: November 17, 2018
Sigma 1 Receptor, Cholesterol and Endoplasmic Reticulum Contact Sites
Vladimir Zhemkov1, Jen Liou1, Ilya Bezprozvanny1,2
1Department of Physiology, UT Southwestern Medical Center at Dallas, Texas, United States.
Abstract:
Recent studies indicated potential importance of membrane contact sites (MCS) between the endoplasmic reticulum (ER) and other cellular organelles. These MCS have unique protein and lipid composition and serve as hubs for inter-organelle communication and signaling. Despite extensive investigation of MCS protein composition and functional roles, little is known about the process of MCS formation. In this perspective, we propose a hypothesis that MCS are formed not as a result of random interactions between membranes of ER and other organelles but on the basis of pre-existing cholesterol-enriched ER microdomains.
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