Prion domain initiation of amyloid formation in vitro from native Ure2p.
The [URE3] non-Mendelian genetic element of Saccharomyces cerevisiae is an infectious protein (prion) form of Ure2p, a regulator of nitrogen catabolism. Here, synthetic Ure2p1-65 were shown to polymerize to form filaments 40 to 45 angstroms in diameter with more than 60 percent beta sheet. Ure2p1-65 specifically induced full-length native Ure2p to copolymerize under conditions where native Ure2p alone did not polymerize. Like Ure2p in extracts of [URE3] strains, these 180- to 220-angstrom-diameter filaments were protease resistant. The Ure2p1-65-Ure2p cofilaments could seed polymerization of native Ure2p to form thicker, less regular filaments. All filaments stained with Congo Red to produce the green birefringence typical of amyloid. This self-propagating amyloid formation can explain the properties of [URE3].
Laboratory of Biochemistry and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0830, USA.
K L
KL
Taylor
N
N
Cheng
R W
RW
Williams
A C
AC
Steven
R B
RB
Wickner
D000682:Amyloid / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D001704:Biopolymers / Q000737:chemistry; D011232:Chemical Precipitation; D004396:Coloring Agents / Q000378:metabolism; D003224:Congo Red / Q000378:metabolism; D019281:Dimerization; D010450:Endopeptidases / Q000378:metabolism; D005656:Fungal Proteins / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D005979:Glutathione Peroxidase; D006358:Hot Temperature; D008854:Microscopy, Electron; D010446:Peptide Fragments / Q000737:chemistry; D011328:Prions / Q000737:chemistry* / Q000378:metabolism / Q000648:ultrastructure; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D029701:Saccharomyces cerevisiae Proteins
D000682:Amyloid; D001704:Biopolymers; D004396:Coloring Agents; D005656:Fungal Proteins; D010446:Peptide Fragments; D011328:Prions; D029701:Saccharomyces cerevisiae Proteins; D003224:Congo Red; D005979:Glutathione Peroxidase; C067020:URE2 protein, S cerevisiae; D010450:Endopeptidases