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Sub-angstrom cryo-EM structure of a prion protofibril reveals a polar clasp.

ABSTRACT: The atomic structure of the infectious, protease-resistant, ?-sheet-rich and fibrillar mammalian prion remains unknown. Through the cryo-EM method MicroED, we reveal the sub-ångström-resolution structure of a protofibril formed by a wild-type segment from the ?2-?2 loop of the bank vole prion protein. The structure of this protofibril reveals a stabilizing network of hydrogen bonds that link polar zippers within a sheet, producing motifs we have named 'polar clasps'.

SUBMITTER: Gallagher-Jones M

PROVIDER: S-EPMC6170007 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

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Sub-ångström cryo-EM structure of a prion protofibril reveals a polar clasp.

Gallagher-Jones Marcus M Glynn Calina C Boyer David R DR Martynowycz Michael W MW Hernandez Evelyn E Miao Jennifer J Zee Chih-Te CT Novikova Irina V IV Goldschmidt Lukasz L McFarlane Heather T HT Helguera Gustavo F GF Evans James E JE Sawaya Michael R MR Cascio Duilio D Eisenberg David S DS Gonen Tamir T Rodriguez Jose A JA

Nature structural & molecular biology 20180115 2

The atomic structure of the infectious, protease-resistant, β-sheet-rich and fibrillar mammalian prion remains unknown. Through the cryo-EM method MicroED, we reveal the sub-ångström-resolution structure of a protofibril formed by a wild-type segment from the β2-α2 loop of the bank vole prion protein. The structure of this protofibril reveals a stabilizing network of hydrogen bonds that link polar zippers within a sheet, producing motifs we have named 'polar clasps'. ...[more]

PMID: 29335561

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