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Conversion of a yeast prion protein to an infectious form in bacteria.

ABSTRACT: Prions are infectious, self-propagating protein aggregates that have been identified in evolutionarily divergent members of the eukaryotic domain of life. Nevertheless, it is not yet known whether prokaryotes can support the formation of prion aggregates. Here we demonstrate that the yeast prion protein Sup35 can access an infectious conformation in Escherichia coli cells and that formation of this material is greatly stimulated by the presence of a transplanted [PSI(+)] inducibility factor, a distinct prion that is required for Sup35 to undergo spontaneous conversion to the prion form in yeast. Our results establish that the bacterial cytoplasm can support the formation of infectious prion aggregates, providing a heterologous system in which to study prion biology.

SUBMITTER: Garrity SJ

PROVIDER: S-EPMC2890818 | biostudies-other | 2010 Jun

REPOSITORIES: biostudies-other

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Conversion of a yeast prion protein to an infectious form in bacteria.

Garrity Sean J SJ Sivanathan Viknesh V Dong Jijun J Lindquist Susan S Hochschild Ann A

Proceedings of the National Academy of Sciences of the United States of America 20100519 23

Prions are infectious, self-propagating protein aggregates that have been identified in evolutionarily divergent members of the eukaryotic domain of life. Nevertheless, it is not yet known whether prokaryotes can support the formation of prion aggregates. Here we demonstrate that the yeast prion protein Sup35 can access an infectious conformation in Escherichia coli cells and that formation of this material is greatly stimulated by the presence of a transplanted [PSI(+)] inducibility factor, a d ...[more]

PMID: 20484678

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