title: Cellular factors important for the de novo formation of yeast prions.
abstract: Prions represent an unusual structural form of a protein that is 'infectious'. In mammals, prions are associated with fatal neurodegenerative diseases such as CJD (Creutzfeldt-Jakob disease), while in fungi they act as novel epigenetic regulators of phenotype. Even though most of the human prion diseases arise spontaneously, we still know remarkably little about how infectious prions form de novo. The [PSI+] prion of the yeast Saccharomyces cerevisiae provides a highly tractable model in which to explore the underlying mechanism of de novo prion formation, in particular identifying key cis- and trans-acting factors. Most significantly, the de novo formation of [PSI+] requires the presence of a second prion called [PIN+], which is typically the prion form of Rnq1p, a protein rich in glutamine and aspartic acid residues. The molecular mechanism by which the [PIN(+)] prion facilitates de novo [PSI+] formation is not fully established, but most probably involves some form of cross-seeding. A number of other cellular factors, in particular chaperones of the Hsp70 (heat-shock protein 70) family, are known to modify the frequency of de novo prion formation in yeast.
authors.affiliation: Protein Science Group, Department of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK. M.F.Tuite@kent.ac.uk
authors.forename: Mick
authors.initials: M
authors.lastname: Tuite
authors.forename: Klement
authors.initials: K
authors.lastname: Stojanovski
authors.forename: Frederique
authors.initials: F
authors.lastname: Ness
authors.forename: Gloria
authors.initials: G
authors.lastname: Merritt
authors.forename: Nadejda
authors.initials: N
authors.lastname: Koloteva-Levine
mesh_terms: D000818:Animals; D006801:Humans; D011328:Prions / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D011328:Prions; D029701:Saccharomyces cerevisiae Proteins