title: Conformation preserved in a weak-to-strong or strong-to-weak [PSI+] conversion during transmission to Sup35 prion variants.
abstract: The cytoplasmic [PSI(+)] element of budding yeast represents the prion conformation of translation release factor Sup35. Much interest lies in understanding how prions are able to generate variation in isogenic strains. Recent observations suggest that a single prion domain, PrD, is able to adopt several conformations that account for prion strains. We report novel PrD variants of Sup35 that convert weak [PSI(+)] to strong [PSI(+)], and vice versa, upon transmission from wild-type Sup35. During the transmission from wild-type Sup35 to variant Sup35s, no conformational changes were detected by proteolytic fingerprinting and the original [PSI(+)] strain was remembered upon return to wild-type Sup35. These findings suggest that during transmission to variant Sup35s, the [PSI(+)] phenotype is variable while the original conformation is remembered. A mechanism of "conformational memory" to remember specific [PSI(+)] conformations during transmission is proposed.
authors.affiliation: Department of Basic Medical Sciences, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Tokyo 108-8639, Japan.
authors.forename: Colin G
authors.initials: CG
authors.lastname: Crist
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kurahashi
authors.forename: Toru
authors.initials: T
authors.lastname: Nakayashiki
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D015966:Gene Expression Regulation, Fungal; D014644:Genetic Variation; D009154:Mutation; D009842:Oligopeptides / Q000235:genetics; D010454:Peptide Termination Factors; D010641:Phenotype; D010957:Plasmids / Q000235:genetics; D011328:Prions / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D011487:Protein Conformation; D017510:Protein Folding; D017434:Protein Structure, Tertiary; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020449:Repetitive Sequences, Amino Acid / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014443:Tyrosine / Q000235:genetics / Q000378:metabolism
chemical_list: D009842:Oligopeptides; D010454:Peptide Termination Factors; D011328:Prions; D011993:Recombinant Fusion Proteins; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D014443:Tyrosine