NR AOPS
AU Aouffen,M.; Villiers,C.; Marche,P.; Vilette,D.; Laude,H.; Favier,A.
TI Transition metal ions promote internalisation, accumulation and cleavage of the prion protein in A74 cells
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - BR-45
PT Konferenz-Poster
AB Prion protein (PrPc) is involved in diverse transmissible, heritable and sporadically occurring neurodegenerative diseases. Recent studies examining the occurrence and consequences of inappropriate cytoplasmic expression of the normally cell-surface PrPc underscore an emerging role for PrPc trafficking in prion disease pathogenesis. Endocytosis of PrP was shown to be enhanced by metal ions such as copper and zinc. However, the internalised form of PrPc and its compartment localisation still under debate. In the present study, we used a A74 Doxocyclin inducible transfected cell to investigate the cellular localisation of PrPc and its metal ion induced internalisation behaviour. Confocal microscopy analysis demonstrated that PrPc is localized on the peri-cellular surface of Doxocyclin treated A74 transfected cells. Copper and zinc but not manganese ions were able to induce a decrease in cell surface expression level of PrPc. Cell permeabilisation by saponin shows an intracytoplasmic accumulation of PrPc in treated A74 cell with copper or zinc, but not with manganese. Accumulation of PrPc was localised in golgi apparatus by co-transfection of A74 cell, using pECP vector, a trans-golgi compartment marker. Surface biotinylation study of metal ions treated A74 cells, suggest an involvement of an internalisation process in the intracellular PrPc accumulation. We used two monoclonal antibodies (SAF 32 and SAF61) raised against both N- and C-terminal region of prion protein that reveal a cleavage of the N-terminal part in the metal ions exposed A74 cell. These data indicate that transition metal ions influence the PrPc traffic by enhancing its internalisation and accumulation and inducing its cleavage in A74 cells. This work was supported by EC (QLRT 200-02353) and Gis Prion (A42-2001).
AD Mhammed Aouffen, Patrice Marche, Alain Favier, DRFMC/LCIB/LAN CEA de Grenoble, France; Christian Villiers, Villiers Christian, 2DSV /DRDC/ ICH, CEA de Grenoble, France; Didier Vilette, Hubert Laude, Unité de Virologie et Immunologie Moléculaire, INRA, 78350 Jouy-en-Josas, France
SP englisch
PO Deutschland