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Apo AI/ABCA1-dependent and HDL3-mediated lipid efflux from compositionally distinct cholesterol-based microdomains.
- Source :
-
Traffic (Copenhagen, Denmark) [Traffic] 2002 Apr; Vol. 3 (4), pp. 268-78. - Publication Year :
- 2002
-
Abstract
- We have investigated whether a raft heterogeneity exists in human monocyte-derived macrophages and fibroblasts and whether these microdomains are modulated by lipid efflux. Triton X-100 (Triton) or Lubrol WX (Lubrol) detergent-resistant membranes from cholesterol-loaded monocytes were associated with the following findings: (i) Lubrol-DRM contained most of the cellular cholesterol and at least 75% of Triton-detergent-resistant membranes. (ii) 'Lubrol rafts', defined by their solubility in Triton but insolubility in Lubrol, were enriched in unsaturated phosphatidylcholine and showed a lower cholesterol to choline-phospholipid ratio compared to Triton rafts. (iii) CD14 and CD55 were recovered in Triton- and Lubrol-detergent-resistant membranes, whereas CD11b was found exclusively in Triton DRM. ABCA1 implicated in apo AI-mediated lipid efflux and CDC42 were partially localized in Lubrol- but not in Triton-detergent-resistant membranes. (iv) Apo AI preferentially depleted cholesterol and choline-phospholipids from Lubrol rafts, whereas HDL3 additionally decreased the cholesterol content of Triton rafts. In fibroblasts, neither ABCA1 nor CDC42 was found in Lubrol rafts, and both apo AI and HDL3 reduced the lipid content in Lubrol- as well as in Triton-detergent-resistant membranes. In summary, we provide evidence for the existence of compositionally distinct membrane microdomains in human cells and their modulation by apo AI/ABCA1-dependent and HDL3-mediated lipid efflux.
- Subjects :
- ATP Binding Cassette Transporter 1
Biological Transport
CD55 Antigens biosynthesis
Cell Membrane metabolism
Cells, Cultured
Choline metabolism
Detergents pharmacology
Electrophoresis, Polyacrylamide Gel
Fibroblasts metabolism
Humans
Immunoblotting
Lipopolysaccharide Receptors biosynthesis
Macrophages metabolism
Membrane Microdomains metabolism
Microscopy, Fluorescence
Microvilli metabolism
Monocytes metabolism
Octoxynol pharmacology
Peptides chemistry
Precipitin Tests
Protein Structure, Tertiary
cdc42 GTP-Binding Protein biosynthesis
ATP-Binding Cassette Transporters metabolism
Apolipoprotein A-I metabolism
Cholesterol metabolism
Lipid Metabolism
Lipoproteins, HDL metabolism
Subjects
Details
- Language :
- English
- ISSN :
- 1398-9219
- Volume :
- 3
- Issue :
- 4
- Database :
- MEDLINE
- Journal :
- Traffic (Copenhagen, Denmark)
- Publication Type :
- Academic Journal
- Accession number :
- 11929608
- Full Text :
- https://doi.org/10.1034/j.1600-0854.2002.030404.x