title: [URE3] and [PSI] are prions of yeast and evidence for new fungal prions.
abstract: [URE3] and [PSI] are two non-Mendelian genetic elements discovered over 25 years ago and never assigned to a nucleic acid replicon. Their genetic properties led us to propose that they are prions, altered self-propagating forms of Ure2p and Sup35p, respectively, that cannot properly carry out the normal functions of these proteins. Ure2p is partially protease-resistant in [URE3] strains and Sup35p is aggregated specifically in [PSI] strains supporting this idea. Overexpression of Hsp104 cures [PSI], as does the absence of this protein, suggesting that the prion change of Sup35p in [PSI] strains is aggregation. Strains of [PSI], analogous to those described for scrapie, have now been described as well as an in vitro system for [PSI] propagation. Recently, two new potential prions have been described, one in yeast and the other in the filamentous fungus, Podospora.
authors.affiliation: National Institutes of Health, Bethesda, MD 20892-0830, USA.
authors.forename: D C
authors.initials: DC
authors.lastname: Masison
authors.forename: H K
authors.initials: HK
authors.lastname: Edskes
authors.forename: M L
authors.initials: ML
authors.lastname: Maddelein
authors.forename: K L
authors.initials: KL
authors.lastname: Taylor
authors.forename: R B
authors.initials: RB
authors.lastname: Wickner
mesh_terms: D000595:Amino Acid Sequence; D005656:Fungal Proteins / Q000235:genetics; D005800:Genes, Fungal; D005979:Glutathione Peroxidase; D008957:Models, Genetic; D008969:Molecular Sequence Data; D009154:Mutation; D010454:Peptide Termination Factors; D010641:Phenotype; D018620:PrPSc Proteins / Q000235:genetics; D011328:Prions / Q000235:genetics*; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins; D020037:Sordariales / Q000235:genetics
chemical_list: D005656:Fungal Proteins; D010454:Peptide Termination Factors; D018620:PrPSc Proteins; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D005979:Glutathione Peroxidase; C067020:URE2 protein, S cerevisiae