NR AURL
AU Kupfer,L.; Proft,J.; Eiden,M.; Buschmann,A.; Groschup,M.H.
TI Conversion of cellular prion protein in a cell-free assay: The influences of amino acid substitutions and different TSE agents with regard to the convertibility of the prion protein
QU TSE-Forum, 6. Kongress - Nationale TSE-Forschungsplattform, Greifswald 26.6.-28.6.2006, Poster: Struktur und molekulare Mechanismen MOL-09
PT Konferenz-Poster
AB
In order to elucidate the early step of the pathogenesis of prion diseases we performed a study which mimics the conversion of PrPc into its pathological isoform PrPsc in vitro. Therefore we used highly purified procaryotically expressed chimaeric PrPc, that consisted either of murine and ovine PrPc or of murine and bovine PrPc and which differed in four amino acids. Mouse passaged scrapie or BSE isolates were used as seeds and the conversion reaction was carried out using a non-radioactive assay without guanidinium. Due to the exclusion of eucaryotic factors, influences on the conversion reaction can be discussed on a molecular basis. We postulate that the convertibility of chimaeric PrPc in vitro depends on its amino acid sequence as well as on the TSE agent which was used as seed. The substitution of single amino acids at distinct positions of PrPc entailed the inconvertibility of the protein after incubation with different PrPsc pathogens. We could also show that strain specific characteristics such as the localisation of the proteinase K cleavage site were transmitted from PrPsc to newly formed PrPres during the conversion process.
These results are generally in line with in vivo data which were obtained in transgenic mice carrying the chimaeric PrPcs.
AD Leila Kupfer, Juliane Proft, Martin Eiden, Anne Buschmann, Martin H. Groschup, Institute for Novel and Emerging Infectious Diseases , Friedrich-Loeffler-Institut, Insel Riems, Germany
SP englisch
PO Deutschland
OR Tagungsband