The Structural Architecture of an Infectious Mammalian Prion Using Electron Cryomicroscopy

PLoS Pathogens

Ludovic Renault¹  Peter J. Peters¹  Marin van Heel¹  Isaac Rosa²  Matthijn R. Vos²  Jesús R. Requena³  Enric Vidal⁴  José Jesús Fernández⁴  Ester Vázquez-Fernández⁴  Pavel Afanasyev⁵  Adriana Ramos⁶  Holger Wille⁷  Lino Cebey⁷  Howard S. Young⁸  Alejandro M. Sevillano⁸ 

[1] CIMUS Biomedical Research Institute University of Santiago de Compostela-IDIS, Santiago de Compostela, Spain;Centre for Prions and Protein Folding Diseases, University of Alberta, Edmonton, Alberta, Canada;Centro Nacional de Biotecnologia - CSIC, Campus Universidad Autónoma, Madrid, Spain;Department of Biochemistry, University of Alberta, Edmonton, Alberta, Canada;FEI Company, Nanoport Europe, Eindhoven, The Netherlands;IRTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB), Campus de la Universitat Autònoma de Barcelona, Bellaterra, Catalonia, Spain;Institute of Biology Leiden, NeCEN, Leiden, The Netherlands;The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands

关键词: Electron cryo-microscopy;    Prion diseases;    Amyloid proteins;    Animal prion diseases;    Crystal structure;    Immunohistochemistry techniques;    Molecular structure;    Protein structure;   

DOI  :  10.1371/journal.ppat.1005835

学科分类：生物科学（综合）

来源: Public Library of Science

【 摘 要 】

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.

【 授权许可】

CC BY