title: Diffusion of sphingomyelin and myelin oligodendrocyte glycoprotein in the membrane of OLN-93 oligodendroglial cells studied by fluorescence correlation spectroscopy.
abstract: Evidence has been accumulated that the plasma membrane of various mammalian cell types is heterogeneous in structure and may contain lipid microdomains (lipid rafts). This study focuses on the membrane organization of living oligodendrocytes, which are the myelin-producing cells of the central nervous system. Fluorescence correlation spectroscopy (FCS) was used to monitor the lateral diffusion of a lipid and of a protein in the oligodendroglial cell line OLN-93. The lipid was fluorescently labelled sphingomyelin (Bodipy FL-C5 SM). The protein was the myelin oligodendrocyte glycoprotein (MOG). In order to monitor the lateral diffusion of MOG, OLN-93 cells were transfected with a MOG-EGFP (enhanced green fluorescent protein) fusion plasmid. The measurements were performed at room temperature. FCS data were analyzed for two-dimensional (2D) diffusion according to three models which all included a triplet fraction: (a) 2D 1 component (2D1C), (b) 2D anomalous diffusion (2D1Calpha), and (c) 2D 2 components (2D2C). Preliminary results indicate that for the lipid case, the best fits are obtained with 2D2C. In the case of MOG-EGFP, 2D2C and 2D1Calpha give fits of similar quality. The parameter estimates obtained with 2D1Calpha, however, have a lower standard deviation. The anomaly parameter for MOG-EGFP is 0.59+/-0.01.
authors.affiliation: Biomedical Research Institute, Hasselt University, transnationale Universiteit Limburg (tUL), Universitaire Campus Bldgs. D and A, B-3590 Diepenbeek, Belgium.
authors.forename: Ellen
authors.initials: E
authors.lastname: Gielen
authors.forename: Jo
authors.initials: J
authors.lastname: Vercammen
authors.forename: Jan
authors.initials: J
authors.lastname: Sýkora
authors.forename: Jana
authors.initials: J
authors.lastname: Humpolickova
authors.forename: Martin
authors.initials: M
authors.lastname: Vandeven
authors.forename: Alés
authors.initials: A
authors.lastname: Benda
authors.forename: Niels
authors.initials: N
authors.lastname: Hellings
authors.forename: Martin
authors.initials: M
authors.lastname: Hof
authors.forename: Yves
authors.initials: Y
authors.lastname: Engelborghs
authors.forename: Paul
authors.initials: P
authors.lastname: Steels
authors.forename: Marcel
authors.initials: M
authors.lastname: Ameloot
mesh_terms: D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism* / Q000648:ultrastructure; D004058:Diffusion; D007700:Kinetics; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein / Q000378:metabolism*; D063308:Myelin-Oligodendrocyte Glycoprotein; D009836:Oligodendroglia / Q000378:metabolism* / Q000648:ultrastructure; D009837:Oligodendroglioma; D051381:Rats; D013050:Spectrometry, Fluorescence; D013109:Sphingomyelins / Q000378:metabolism*
chemical_list: C571328:Mog protein, rat; D009185:Myelin Proteins; D018992:Myelin-Associated Glycoprotein; D063308:Myelin-Oligodendrocyte Glycoprotein; D013109:Sphingomyelins