NR AOVR
AU Leffers,K.W.; Wille,H.; Stoehr,J.; Junger,E.; Prusiner,S.B.; Riesner,D.
TI Induction of amyloidic structures of prion proteins
QU International Conference - Prion diseases: from basic research to intervention concepts - TSE-Forum, 08.10.-10.10.2003, Gasteig, München - Poster session - BR-31
PT Konferenz-Poster
AB
Conversion of the alpha-helical, protease sensitive and non-infectious form of the prion protein (PrPc) to the insoluble, protease resistant, predominantly beta-sheeted or beta-helical and infectious form (PrPsc) plays a key role in the development of prion diseases.
To simulate the structural transition in vitro we developed a system to solubilize PrP 27-30 from prion rods purified from brains of scrapie infected hamsters: Addition of 0.2% SDS followed by sonication and gel-elution leads to solubilized PrP 27-30 (sol PrP 27-30), which is monomeric, has a mainly alpha-helical structure and lacks infectivity. Dilution of the SDS down to 0.01% and addition of physiological concentrations of NaCl lead to a structural transition to a form rich in beta-sheet accompanied by multimerization and an increased PK resistance. Longer incubation times induce the formation of amyloidic fibres as revealed by electron microscopy. The presence of specific sphingolipids that are found as secondary components of prion rods enhances fibre formation. Under similar conditions formation of amyloidic fibres could also be induced with full length PrPc from brains of uninfected hamsters and with an N-terminally truncated, not posttranslational modified recombinant form of PrP denoted rec PrP 90-231. At present the infectivity of the newly formed amyloidic fibres is analyzed by bioassays.
AD K.-W. Leffers, J. Stoehr, D. Riesner, Universität Düsseldorf, Germany; H. Wille, S.B. Prusiner, UCSF, USA; E. Junger, Deutsches Diabetesforschungsinstitut Düsseldorf, Germany
SP englisch
PO Deutschland