title: Tonoplast of Beta vulgaris L. contains detergent-resistant membrane microdomains.
abstract: The experiments conducted on tonoplast of Beta vulgaris L. roots were performed to identify detergent-resistant lipid-protein microdomains (DRMs, interpreted as lipid rafts).The presence of DRMs can be found when dynamic clustering of sphingolipids, sterols, saturated fatty acids is registered, and the insolubility of these microdomains in nonionic detergents at low temperatures is proven. The elucidation of tonoplast microdomains has been based on results obtained with the aid of high-speed centrifuging in the sucrose gradient. The experiments have shown that tonoplast microdomains are rich in sphingolipids, free sterols and saturated fatty acids (such a lipid content is also typical of lipid-protein microdomains of other membranes), while only few phospholipids are present in tonoplast microdomains. The presence of microdomains has been confirmed by fluorescence and confocal microscopy using filipin and Laurdan as fluorescent probes. The experiments with Laurdan have shown that tonoplast microdomains are characterized by a high order compared to characteristics of the rest of the tonoplast. Thus, the presence of detergent-resistant lipid-protein microdomains in the tonoplast has been demonstrated.
authors.affiliation: Siberian Institute of Plant Physiology and Biochemistry, Siberian Branch, Russian Academy of Sciences, 132, Lermontov St., Irkutsk, 664033, Russia. ozol@sifibr.irk.ru
authors.forename: Natalia V
authors.initials: NV
authors.lastname: Ozolina
authors.forename: Irina S
authors.initials: IS
authors.lastname: Nesterkina
authors.forename: Ekaterina V
authors.initials: EV
authors.lastname: Kolesnikova
authors.forename: Ryurik K
authors.initials: RK
authors.lastname: Salyaev
authors.forename: Vadim N
authors.initials: VN
authors.lastname: Nurminsky
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Rakevich
authors.forename: Evgueni F
authors.initials: EF
authors.lastname: Martynovich
authors.forename: Michael Yu
authors.initials: MY
authors.lastname: Chernyshov
mesh_terms: D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000378:metabolism; D027461:Beta vulgaris / Q000187:drug effects / Q000378:metabolism*; D002499:Centrifugation, Density Gradient; D003902:Detergents / Q000494:pharmacology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005227:Fatty Acids / Q000378:metabolism; D007425:Intracellular Membranes / Q000187:drug effects / Q000378:metabolism*; D007848:Laurates / Q000378:metabolism; D021962:Membrane Microdomains / Q000187:drug effects / Q000378:metabolism*; D010940:Plant Proteins / Q000378:metabolism; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000378:metabolism; D013261:Sterols / Q000378:metabolism; D014617:Vacuoles / Q000187:drug effects / Q000378:metabolism*
chemical_list: D003902:Detergents; D004791:Enzyme Inhibitors; D005227:Fatty Acids; D007848:Laurates; D010940:Plant Proteins; D013261:Sterols; D015081:2-Naphthylamine; D006180:Proton-Translocating ATPases; C065580:laurdan