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LDL Cholesterol Uptake Assay Using Live Cell Imaging Analysis with Cell Health Monitoring
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LDL-cholesterol transport to the endoplasmic reticulum: current concepts
Simon G Pfisterer1, Johan Peränen, Elina Ikonen
1Department of Anatomy and Research Programs Unit, Faculty of Medicine, University of Helsinki, Finland and Minerva Foundation Institute for Medical Research, Helsinki, Finland.
Current Opinion in Lipidology
|April 8, 2016
Summary
This review explores cholesterol export from late endosomes to the endoplasmic reticulum (ER), focusing on Nieman-Pick C1 (NPC1) disease. Membrane contact sites (MCSs) are highlighted as potential pathways for this crucial lipid transfer.
Area of Science:
- Cell Biology
- Lipid Metabolism
- Molecular Medicine
Background:
- Cholesterol homeostasis is vital for cellular function.
- Nieman-Pick disease type C1 (NPC1) disrupts cholesterol trafficking.
- Late endosomes and the endoplasmic reticulum (ER) are key organelles in cholesterol transport.
Purpose of the Study:
- To summarize current knowledge on LDL-derived cholesterol export from late endosomes.
- To focus on NPC1-mediated cholesterol delivery to the ER.
- To review the role of membrane contact sites (MCSs) in this process.
Main Methods:
- Literature review of studies on cholesterol transport pathways.
- Analysis of data on protein bridges at late endosome-ER contacts.
- Examination of findings from yeast models of lipid transfer.
Main Results:
- Multiple pathways, including MCSs, may mediate cholesterol export.
- Specific protein bridges (ORP1L-VAP, StARαD3-VAP, ORP5-NPC1) are identified at endosome-ER contacts.
- The contribution of MCSs to LDL-cholesterol flux to the ER requires further investigation.
Conclusions:
- MCSs represent a significant mechanism for intermembrane lipid transfer.
- Further research is needed to elucidate specific MCSs involved in cholesterol delivery to the ER.
- Understanding these pathways is crucial for managing cholesterol-related disorders.
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