English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

[PSI+] is a prion (infectious protein) of Sup35p, a subunit of the Saccharomyces cerevisiae translation termination factor. We isolated a dominant allele, SSA1-21, of a gene encoding an Hsp70 chaperone that impairs [PSI+] mitotic stability and weakens allosuppression caused by [PSI+]. While [PSI+] stability is normal in strains lacking SSA1, SSA2, or both, SSA1-21 strains with a deletion of SSA2 cannot propagate [PSI+]. SSA1-21 [PSI+] strains are hypersensitive to curing of [PSI+] by guanidine-hydrochloride and partially cured of [PSI+] by rapid induction of the heat-shock response but not by growth at 37°. The number of inheritable [PSI+] particles is significantly reduced in SSA1-21 cells. SSA1-21 effects on [PSI+] appear to be independent of Hsp104, another stress-inducible protein chaperone known to be involved in [PSI+] propagation. We propose that cytosolic Hsp70 is important for the formation of Sup35p polymers characteristic of [PSI+] from preexisting material and that Ssa1-21p both lacks and interferes with this activity. We further demonstrate that the negative effect of heat stress on [PSI+] phenotype directly correlates with solubility of Sup35p and find that in wild-type strains the presence of [PSI+] causes a stress that elevates basal expression of Hsp104 and SSA1.

A Role for Cytosolic Hsp70 in Yeast [PSI+] Prion Propagation and [PSI+] as a Cellular Stress