Variant-specific [PSI+] infection is transmitted by Sup35 polymers within [PSI+] aggregates with heterogeneous protein composition.

ABSTRACT: The [PSI(+)] prion is the aggregated self-propagating form of the Sup35 protein from the yeast Saccharomyces cerevisiae. Aggregates of Sup35 in [PSI(+)] cells exist in different heritable conformations, called "variants," and they are composed of detergent-resistant Sup35 polymers, which may be closely associated with themselves, other proteins, or both. Here, we report that disassembly of the aggregates into individual Sup35 polymers and non-Sup35 components increases their infectivity while retaining their variant specificity, showing that variant-specific [PSI(+)] infection can be transmitted by Sup35 polymers alone. Morphological analysis revealed that Sup35 isolated from [PSI(+)] yeast has the appearance of short barrels, and bundles, which seem to be composed of barrels. We show that

SUBMITTER: Bagriantsev SN 

PROVIDER: S-EPMC2397312 | biostudies-literature | 2008 Jun

REPOSITORIES: biostudies-literature