Ssb1 chaperone is a [PSI+] prion-curing factor.
Yeast SUP7' or SUP11 nonsense suppressors have no phenotypic expression in strains deficient in the isopentenylation of A37 in tRNA. Here we show that such strains spontaneously produce cells with a nonsense suppressor phenotype which is related to the cytoplasmically inherited determinant and manifests all the key features of the [PSI+] prion. A screen of a multicopy yeast genomic library for genes that inactivate the [PSI+]-related suppressor phenotype resulted in the isolation of the SSB1 gene. Moreover, we demonstrate that multicopy plasmid encoding the Ssb1 chaperone cures cells of the [PSI+] prion.
Chacinska
A
A
Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5A, 02106 Warsaw, Poland.
Szczesniak
B
B
Kochneva-Pervukhova
N V
NV
Kushnirov
V V
VV
Ter-Avanesyan
M D
MD
Boguta
M
M
D000818:Animals; D003001:Cloning, Molecular; D018389:Codon, Nonsense; D005656:Fungal Proteins / Q000235:genetics*; D005800:Genes, Fungal / Q000235:genetics; D005838:Genotype; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D018832:Molecular Chaperones / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D010641:Phenotype; D010957:Plasmids / Q000235:genetics; D011328:Prions / Q000235:genetics / Q000378:metabolism*; D012343:RNA, Transfer / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013489:Suppression, Genetic
D018389:Codon, Nonsense; D005656:Fungal Proteins; D018840:HSP70 Heat-Shock Proteins; D018832:Molecular Chaperones; D011328:Prions; C095192:SSB1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D012343:RNA, Transfer