NR ATTS
AU Leffers,K.W.; Wille,H.; Stohr,J.; Junger,E.; Prusiner,S.B.; Riesner,D.
TI Assembly of natural and recombinant prion protein into fibrils
QU Biological Chemistry 2005 Jun; 386(6): 569-80
PT journal article
AB The conversion of the alpha-helical, cellular isoform of the prion protein (PrPc) to the insoluble, beta-sheet-rich, infectious, disease-causing isoform (PrPsc) is the fundamental event in the prion diseases. The C-terminal fragment of PrPsc (PrP 27-30) is formed by limited proteolysis and retains infectivity. Unlike full-length PrPsc, PrP 27-30 polymerizes into rod-shaped structures with the ultra-structural and tinctorial properties of amyloid. To study the folding of PrP, both with respect to the formation of PrPsc from PrPc and the assembly of rods from PrP 27-30, we solubilized Syrian hamster (sol SHa) PrP 27-30 in low concentrations (0.2%) of sodium dodecyl sulfate (SDS) under conditions previously used to study the structural transitions of this protein. Sol SHaPrP 27-30 adopted a beta-sheet-rich structure at SDS concentrations between 0.02% and 0.04% and remained soluble. Here we report that NaCl stabilizes SHaPrP 27-30 in a soluble, beta-sheet-rich state that allows fibril assembly to proceed over several weeks. Under these conditions, fibril formation occurred not only with sol PrP 27-30, but also with native SHaPrPc. Addition of sphingolipids seems to increase fibril growth. When recombinant (rec) SHaPrP(90-231) was exposed to low concentrations of SDS, similar to those used to polymerize sol SHaPrP 27-30 in the presence of 250 mM NaCl, fibril formation occurred regularly. When fibrils formed from PrP 27-30 or PrPc were bioassayed in transgenic mice overexpressing full-length SHaPrP, no infectivity was obtained, whereas amyloid fibrils formed of rec mouse PrP(89-230) were infectious. At present, it cannot be determined whether the lack of infectivity is caused by a difference in the structure of the fibrils or in the bioassay conditions.
MH Amyloid/*metabolism/ultrastructure; Animals; Brain Chemistry; Cricetinae; Endopeptidase K/metabolism; Mesocricetus; Mice; Mice, Transgenic; Peptide Fragments/chemistry; PrPc Proteins/*chemistry/metabolism/*pathogenicity; PrPsc Proteins/*chemistry/metabolism/*pathogenicity; Recombinant Proteins/chemistry
AD Institut für Physikalische Biologie und Biologisch-Medizinisches Forschungszentrum, Heinrich-Heine-Universität Düsseldorf, D-40225 Düsseldorf, Germany.
SP englisch
PO Deutschland