title: A bipolar personality of yeast prion proteins.
abstract: Prions are infectious, self-propagating protein conformations. [PSI+], [RNQ+] and [URE3] are well characterized prions in Saccharomyces cerevisiae and represent the aggregated states of the translation termination factor Sup35, a functionally unknown protein Rnq1, and a regulator of nitrogen metabolism Ure2, respectively. Overproduction of Sup35 induces the de novo appearance of the [PSI+] prion in [RNQ+] or [URE3] strain, but not in non-prion strain. However, [RNQ+] and [URE3] prions themselves, as well as overexpression of a mutant Rnq1 protein, Rnq1Δ100, and Lsm4, hamper the maintenance of [PSI+]. These findings point to a bipolar activity of [RNQ+], [URE3], Rnq1Δ100, and Lsm4, and probably other yeast prion proteins as well, for the fate of [PSI+] prion. Possible mechanisms underlying the apparent bipolar activity of yeast prions will be discussed.
authors.affiliation: Department of Basic Medical Sciences, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kurahashi
authors.forename: Keita
authors.initials: K
authors.lastname: Oishi
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D000682:Amyloid / Q000378:metabolism; D010454:Peptide Termination Factors / Q000378:metabolism; D011328:Prions / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: D000682:Amyloid; D010454:Peptide Termination Factors; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins