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Non-vesicular sterol transport in cells
1Laboratory of Cell Biochemistry and Biology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, US Department of Health and Human Services, Bethesda, MD 20892, USA. wprinz@helix.nih.gov
Progress in Lipid Research
|August 22, 2007
Summary
Cellular sterols, like cholesterol, are vital membrane components. This review explores proteins that traffic sterols non-vesicularly, impacting cellular functions and distribution.
Area of Science:
- Cell Biology
- Molecular Biology
- Biochemistry
Background:
- Sterols, including cholesterol, are essential for cellular membrane structure and function.
- Sterol distribution is non-uniform across organelles, and maintaining proper levels is critical.
- Both vesicular and non-vesicular pathways facilitate sterol transport within cells and across the plasma membrane.
Purpose of the Study:
- To review current knowledge on proteins involved in non-vesicular sterol transport.
- To discuss the roles of these proteins in intracellular sterol trafficking and distribution.
- To highlight the poorly understood mechanisms and regulation of these sterol-modulating proteins.
Main Methods:
- Literature review of recent studies on sterol transport proteins.
- Analysis of proposed mechanisms for both soluble and integral membrane sterol transfer proteins.
- Synthesis of information on sterol efflux, uptake, and intracellular transfer mediated by these proteins.
Main Results:
- Several proteins, both soluble and integral membrane types, have been identified as potential sterol transporters.
- These proteins are implicated in moving sterols between membranes, cellular uptake, and efflux.
- The precise mechanisms and regulatory networks governing these proteins are largely unknown.
Conclusions:
- Non-vesicular sterol transport pathways are increasingly recognized as critical for cellular homeostasis.
- Identified proteins offer potential targets for understanding and manipulating sterol distribution.
- Further research is needed to elucidate the function and regulation of these key sterol trafficking proteins.
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