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Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient
Published on: September 3, 2014
Cholesterol asymmetry in synaptic plasma membranes
W Gibson Wood1, Urule Igbavboa, Walter E Müller
1Department of Pharmacology, University of Minnesota, School of Medicine, Minneapolis, MN 55455, USA. woodx002@umn.edu
Journal of Neurochemistry
|January 11, 2011
Summary
Cholesterol is asymmetrically distributed in synaptic plasma membranes, with the cytofacial leaflet containing most. This cholesterol asymmetry is dynamic and influenced by factors like ethanol, statins, aging, and apoE, impacting membrane function.
Area of Science:
- Membrane biophysics
- Neurobiology
- Lipid biochemistry
Background:
- Membrane lipids form domains, often associated with cholesterol.
- Lipid rafts and caveolae are known cholesterol-rich domains.
- Plasma membranes have distinct exofacial and cytofacial leaflets with differing properties.
Purpose of the Study:
- To review cholesterol asymmetry in the synaptic plasma membrane (SPM).
- To explore mechanisms regulating SPM cholesterol distribution.
- To understand the impact of cholesterol asymmetry on membrane structure and function.
Main Methods:
- Literature review focusing on synaptic plasma membrane cholesterol.
- Analysis of factors influencing cholesterol distribution in vivo.
- Examination of proposed regulatory mechanisms for cholesterol asymmetry.
Main Results:
- The synaptic plasma membrane (SPM) cytofacial leaflet contains over 85% of total SPM cholesterol.
- Cholesterol asymmetry is modulated by chronic ethanol consumption, statins, aging, and apoE isoform.
- Multiple proteins and lipids are implicated in regulating SPM cholesterol asymmetry.
Conclusions:
- Cholesterol asymmetry in the synaptic plasma membrane is a significant feature.
- Factors like ethanol, statins, aging, and apoE dynamically regulate this asymmetry.
- Understanding these mechanisms is crucial for comprehending membrane structure and function.
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