title: Prion-induced and spontaneous formation of transmissible toxicity in PrP transgenic Drosophila.
abstract: Prion diseases are fatal transmissible neurodegenerative diseases of various mammalian species. Central to these conditions is the conversion of the normal host prion protein PrP(C) into the abnormal prion conformer PrP(Sc). Mature PrP(C) is attached to the plasma membrane by a glycosylphosphatidylinositol anchor, whereas during biosynthesis and metabolism cytosolic and secreted forms of the protein may arise. The role of topological PrP(C) variants in the mechanism of prion formation and prion-induced neurotoxicity during prion disease remains undefined. In the present study we investigated whether Drosophila transgenic for ovine PrP targeted to the plasma membrane, to the cytosol or for secretion, could produce transmissible toxicity following exposure to exogenous ovine prions. Although all three topological variants of PrP were efficiently expressed in Drosophila, cytosolic PrP was conformationally distinct and required denaturation before recognition by immunobiochemical methods. Adult Drosophila transgenic for pan neuronally expressed ovine PrP targeted to the plasma membrane, to the cytosol or for secretion exhibited a decreased locomotor activity after exposure at the larval stage to ovine prions. Proteinase K-resistant PrP(Sc) was detected by protein misfolding cyclic amplification in prion-exposed Drosophila transgenic for membrane-targeted PrP. Significantly, head homogenate from all three variants of prion-exposed PrP transgenic Drosophila induced a decreased locomotor activity when transmitted to PrP recipient flies. Drosophila transgenic for PrP targeted for secretion exhibited a spontaneous locomotor defect in the absence of prion exposure that was transmissible in PrP transgenic flies. Our data are consistent with the formation of transmissible prions in PrP transgenic Drosophila.
authors.affiliation: *University of Cambridge, Department of Veterinary Medicine, Madingley Road, Cambridge CB3 OES, U.K.
authors.forename: Alana M
authors.initials: AM
authors.lastname: Thackray
authors.affiliation: *University of Cambridge, Department of Veterinary Medicine, Madingley Road, Cambridge CB3 OES, U.K.
authors.forename: Ying
authors.initials: Y
authors.lastname: Di
authors.affiliation: *University of Cambridge, Department of Veterinary Medicine, Madingley Road, Cambridge CB3 OES, U.K.
authors.forename: Chang
authors.initials: C
authors.lastname: Zhang
authors.affiliation: †German Center for Neurodegenerative Diseases (DZNE e.V.), Rheinische Friedrich-Wilhelms-Universität, 53175 Bonn, Germany.
authors.forename: Hanna
authors.initials: H
authors.lastname: Wolf
authors.affiliation: †German Center for Neurodegenerative Diseases (DZNE e.V.), Rheinische Friedrich-Wilhelms-Universität, 53175 Bonn, Germany.
authors.forename: Lydia
authors.initials: L
authors.lastname: Pradl
authors.forename: Ina
authors.initials: I
authors.lastname: Vorberg
authors.affiliation: §UMR INRA ENVT 1225 -Hôtes-Agents Pathogènes, Ecole Nationale Vétérinaire de Toulouse, 23 chemin des Capelles, 31076 Toulouse, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Andréoletti
authors.affiliation: *University of Cambridge, Department of Veterinary Medicine, Madingley Road, Cambridge CB3 OES, U.K.
authors.forename: Raymond
authors.initials: R
authors.lastname: Bujdoso
mesh_terms: D000818:Animals; D030801:Animals, Genetically Modified; D002462:Cell Membrane / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D004331:Drosophila melanogaster; D018621:PrPC Proteins / Q000235:genetics / Q000378:metabolism*; D017096:Prion Diseases / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D012756:Sheep
chemical_list: D018621:PrPC Proteins