title: The ATP-binding cassette (ABC) transporter Bpt1p mediates vacuolar sequestration of glutathione conjugates in yeast.
abstract: Vacuolar sequestration or cellular extrusion of glutathione-conjugated xenobiotics and catabolites by ATP-binding cassette (ABC) transporters is an important detoxification mechanism operating in many species. In this study, we show that the yeast ABC transporter Bpt1p, a paralogue of Ycf1p, acts as an ATP-dependent vacuolar pump for glutathione conjugates. Bpt1p, which is inhibited by vanadate and glibenclamide, accounts for one third of the total vacuolar transport of glutathione conjugates. Furthermore, immunoblot analyses show that Bpt1p levels are strongly elevated in early stationary phase, consistent with a function of Bpt1p in vacuolar detoxification.
authors.affiliation: Institut de Botanique, Laboratoire de Physiologie Végétale, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland.
authors.forename: Markus
authors.initials: M
authors.lastname: Klein
authors.forename: Yasmine M
authors.initials: YM
authors.lastname: Mamnun
authors.forename: Thomas
authors.initials: T
authors.lastname: Eggmann
authors.forename: Christoph
authors.initials: C
authors.lastname: Schüller
authors.forename: Hubert
authors.initials: H
authors.lastname: Wolfger
authors.forename: Enrico
authors.initials: E
authors.lastname: Martinoia
authors.forename: Karl
authors.initials: K
authors.lastname: Kuchler
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D001692:Biological Transport / Q000187:drug effects; D002104:Cadmium / Q000494:pharmacology; D004137:Dinitrochlorobenzene / Q000494:pharmacology; D005978:Glutathione / Q000378:metabolism*; D049452:Green Fluorescent Proteins; D015151:Immunoblotting; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D018613:Microscopy, Confocal; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000378:metabolism*; D014617:Vacuoles / Q000378:metabolism*
chemical_list: D018528:ATP-Binding Cassette Transporters; D004137:Dinitrochlorobenzene; D008164:Luminescent Proteins; D008565:Membrane Proteins; D011993:Recombinant Fusion Proteins; D002104:Cadmium; D049452:Green Fluorescent Proteins; D000255:Adenosine Triphosphate; D005978:Glutathione