title: Separation of caveolae from associated microdomains of GPI-anchored proteins.
abstract: In situ coating of the surface of endothelial cells in rat lung with cationic colloidal silica particles was used to separate caveolae from detergent-insoluble membranes rich in glycosyl phosphatidylinositol (GPI)-anchored proteins but devoid of caveolin. Immunogold electron microscopy showed that ganglioside GM1-enriched caveolae associated with an annular plasmalemmal domain enriched in GPI-anchored proteins. The purified caveolae contained molecular components required for regulated transport, including various lipid-anchored signaling molecules. Such specialized distinct microdomains may exist separately or together in the plasma membrane to organize signaling molecules and to process surface-bound ligands differentially.
authors.affiliation: Department of Pathology, Harvard Medical School, Beth Israel Hospital, Boston, MA 02215, USA.
authors.forename: J E
authors.initials: JE
authors.lastname: Schnitzer
authors.forename: D P
authors.initials: DP
authors.lastname: McIntosh
authors.forename: A M
authors.initials: AM
authors.lastname: Dvorak
authors.forename: J
authors.initials: J
authors.lastname: Liu
authors.forename: P
authors.initials: P
authors.lastname: Oh
mesh_terms: D015720:5'-Nucleotidase / Q000032:analysis; D000818:Animals; D051242:Caveolin 1; D022461:Caveolins; D002458:Cell Fractionation; D002462:Cell Membrane / Q000737:chemistry* / Q000648:ultrastructure*; D003102:Colloids; D003902:Detergents; D004730:Endothelium, Vascular / Q000648:ultrastructure; D017261:Glycosylphosphatidylinositols / Q000032:analysis*; D008565:Membrane Proteins / Q000032:analysis*; D016253:Microscopy, Immunoelectron; D051381:Rats; D011956:Receptors, Cell Surface / Q000032:analysis; D055293:Receptors, Urokinase Plasminogen Activator; D015398:Signal Transduction; D012822:Silicon Dioxide; D012995:Solubility
chemical_list: C495537:Cav1 protein, rat; D051242:Caveolin 1; D022461:Caveolins; D003102:Colloids; D003902:Detergents; D017261:Glycosylphosphatidylinositols; D008565:Membrane Proteins; C524900:Plaur protein, rat; D011956:Receptors, Cell Surface; D055293:Receptors, Urokinase Plasminogen Activator; D012822:Silicon Dioxide; D015720:5'-Nucleotidase