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Isolation of Cellular Lipid Droplets: Two Purification Techniques Starting from Yeast Cells and Human Placentas
Published on: April 1, 2014
PNPLA3/adiponutrin functions in lipid droplet formation.
Zeina Chamoun1, Fabrizio Vacca1, Robert G Parton2
1Department of Biochemistry, University of Geneva, Geneva 4, Switzerland.
Biology of the Cell
|February 13, 2013
Summary
Patatin-like phospholipase domain-containing 3 (PNPLA3) plays a dual role in lipid droplet metabolism, aiding lipid homeostasis during excessive fat accumulation. This research clarifies PNPLA3
Area of Science:
- Cell Biology
- Metabolic Diseases
- Lipid Metabolism
Background:
- Lipid droplets (LDs) store energy as triacylglycerol (TAG) and esterified cholesterol (CE).
- Non-alcoholic fatty liver disease (NAFLD) involves excessive liver TAG accumulation.
- A variant in patatin-like phospholipase domain-containing 3 (PNPLA3) is linked to NAFLD susceptibility.
Purpose of the Study:
- To elucidate the physiological role and sub-cellular distribution of PNPLA3.
- To investigate the mechanism by which PNPLA3 variants influence NAFLD.
Main Methods:
- Gene screening for PNPLA3 upregulation during lipid accumulation.
- Sub-cellular localization studies of PNPLA3 in lipid-supplemented fibroblast-like cells.
- Analysis of LD size and composition following manipulation of PNPLA3 levels and co-expression with ABDH5/CGI-58.
Main Results:
- PNPLA3 localizes to LDs, requiring an intact Brummer box domain.
- Increased PNPLA3 levels enlarge LDs; decreased levels reduce LD size.
- PNPLA3 reduces LD size upon co-expression with ABDH5/CGI-58, an activator of PNPLA2.
Conclusions:
- PNPLA3 exhibits a dual function in lipid droplet metabolism.
- PNPLA3 participates in restoring lipid homeostasis following aberrant intracellular lipid accumulation.
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