Epigenetic control of polyamines by the prion [PSI+].
Prion proteins are found in mammals and yeast, and can transmit diseases and encode heritable phenotypic traits. In Saccharomyces cerevisiae, eRF3, Rnq1, Ure2 and Swil are functional proteins with a soluble conformation that can switch to a non-functional, amyloid conformation denoted as [PSI+], [PIN+], [URE3] and [SWI+], respectively. The prion [PSI+] corresponds to an aggregated conformation of the translational release factor eRF3, which suppresses nonsense codons. [PSI+] modifies cellular fitness and induces several phenotypes according to the genetic background. An elegant series of studies has demonstrated that several [PSI+]-induced phenotypes occur as a consequence of decreased translational termination efficiency. However, the genes whose expression levels are controlled by [PSI+] remain largely unknown. Here, we show that [PSI+] enhances expression of antizyme, a negative regulator of cellular polyamines, by modulating the +1 frameshifting required for its expression. Our study also demonstrates that [PSI+] greatly affects cellular polyamines in yeast. We show that modification of the cellular content of polyamines by the prion accounts for half of the [PSI+]-induced phenotypes. Antizyme is the first protein to be described for which expression of its functional form is stimulated by [PSI+].
Namy
Olivier
O
IGM, CNRS, UMR 8621, Orsay, 91405 France. olivier.namy@igmors.u-psud.fr
Galopier
Aurélie
A
Martini
Cyrielle
C
Matsufuji
Senya
S
Fabret
Céline
C
Rousset
Jean-Pierre
JP
D044127:Epigenesis, Genetic; D042541:Intracellular Space / Q000378:metabolism; D008954:Models, Biological; D010454:Peptide Termination Factors / Q000737:chemistry* / Q000378:metabolism*; D010641:Phenotype; D011073:Polyamines / Q000378:metabolism*; D011328:Prions / Q000737:chemistry* / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism*
D010454:Peptide Termination Factors; D011073:Polyamines; D011328:Prions; C068068:SUP35 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; C087971:peptide-chain-release factor 3