Selfish prion of Rnq1 mutant in yeast.
[PIN(+)] is a prion form of Rnq1 in Saccharomyces cerevisiae and is necessary for the de novo induction of a second prion, [PSI(+)]. We previously isolated a truncated form of Rnq1, named Rnq1Delta100, as a [PSI(+)]-eliminating factor in S. cerevisiae. Rnq1Delta100 deletes the N-terminal non-prion domain of Rnq1, and eliminates [PSI(+)] in [PIN(+)] yeast. Here we found that [PIN(+)] is transmissible to Rnq1Delta100 in the absence of full-length Rnq1, forming a novel prion variant [RNQ1Delta100(+)]. [RNQ1Delta100(+)] has similar [PIN(+)] properties as it stimulates the de novo induction of [PSI(+)] and is eliminated by the null hsp104Delta mutation, but not by Hsp104 overproduction. In contrast, [RNQ1Delta100(+)] inherits the inhibitory activity and hampers the maintenance of [PSI(+)] though less efficiently than [PIN(+)] made of Rnq1-Rnq1Delta100 co-aggregates. Interestingly, [RNQ1Delta100(+)] prion was eliminated by de novo [PSI(+)] induction. Thus, the [RNQ1Delta100(+)] prion demonstrates selfish activity to eliminate a heterologous prion in S. cerevisiae, showing the first instance of a selfish prion variant in living organisms.
Department of Basic Medical Sciences, Institute of Medical Science, University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Hiroshi
H
Kurahashi
Shoichiro
S
Shibata
Masao
M
Ishiwata
Yoshikazu
Y
Nakamura
D017353:Gene Deletion; D014644:Genetic Variation / Q000235:genetics; D009154:Mutation / Q000235:genetics*; D010641:Phenotype; D011328:Prions / Q000235:genetics* / Q000378:metabolism*; D011487:Protein Conformation; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism*
D011328:Prions; C404807:RNQ1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins