The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy.
The structure of the infectious prion protein (PrPSc), which is responsible for Creutzfeldt-Jakob disease in humans and bovine spongiform encephalopathy, has escaped all attempts at elucidation due to its insolubility and propensity to aggregate. PrPSc replicates by converting the non-infectious, cellular prion protein (PrPC) into the misfolded, infectious conformer through an unknown mechanism. PrPSc and its N-terminally truncated variant, PrP 27-30, aggregate into amorphous aggregates, 2D crystals, and amyloid fibrils. The structure of these infectious conformers is essential to understanding prion replication and the development of structure-based therapeutic interventions. Here we used the repetitive organization inherent to GPI-anchorless PrP 27-30 amyloid fibrils to analyze their structure via electron cryomicroscopy. Fourier-transform analyses of averaged fibril segments indicate a repeating unit of 19.1 Å. 3D reconstructions of these fibrils revealed two distinct protofilaments, and, together with a molecular volume of 18,990 Å3, predicted the height of each PrP 27-30 molecule as ~17.7 Å. Together, the data indicate a four-rung β-solenoid structure as a key feature for the architecture of infectious mammalian prions. Furthermore, they allow to formulate a molecular mechanism for the replication of prions. Knowledge of the prion structure will provide important insights into the self-propagation mechanisms of protein misfolding.
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.|Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
Ester
E
Vázquez-Fernández
FEI Company, Nanoport Europe, Eindhoven, The Netherlands.
Matthijn R
MR
Vos
Institute of Biology Leiden, NeCEN, Leiden, The Netherlands.|The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands.
Pavel
P
Afanasyev
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.|Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
Lino
L
Cebey
CIMUS Biomedical Research Institute University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain.
Alejandro M
AM
Sevillano
IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain.
Enric
E
Vidal
CIMUS Biomedical Research Institute University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain.
Isaac
I
Rosa
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.
Ludovic
L
Renault
CIMUS Biomedical Research Institute University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain.
Adriana
A
Ramos
The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands.
Peter J
PJ
Peters
Centro Nacional de Biotecnologia - CSIC, Campus Universidad Autónoma, Madrid, Spain.
José Jesús
JJ
Fernández
Institute of Biology Leiden, NeCEN, Leiden, The Netherlands.|Brazilian Nanotechnology National Laboratory - LNNano, CNPEM, Campinas, São Paulo, Brazil.|Faculty of Natural Science, Imperial College London, London, United Kingdom.
Marin
M
van Heel
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.
Howard S
HS
Young
CIMUS Biomedical Research Institute University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain.
Jesús R
JR
Requena
Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada.|Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada.
Holger
0000-0001-5102-8706
H
Wille
D000682:Amyloid / Q000235:genetics / Q000648:ultrastructure*; D000818:Animals; D002417:Cattle; D007562:Creutzfeldt-Jakob Syndrome / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D020285:Cryoelectron Microscopy; D016643:Encephalopathy, Bovine Spongiform / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D006801:Humans; D018621:PrPC Proteins / Q000235:genetics / Q000648:ultrastructure*; D018620:PrPSc Proteins / Q000235:genetics / Q000648:ultrastructure*
D000682:Amyloid; D018621:PrPC Proteins; D018620:PrPSc Proteins