NR ADRO
AU Eaglestone,S.S.; Cox,B.S.; Tuite,M.F.
TI Translation termination efficiency can be regulated in Saccharomyces cerevisiae by environmental stress through a prion-mediated mechanism
QU EMBO Journal 1999 Apr 1; 18(7): 1974-81
PT journal article
AB [PSI+] is a protein-based heritable phenotype of the yeast Saccharomyces cerevisiae which reflects the prion-like behaviour of the endogenous Sup35p protein release factor. [PSI+] strains exhibit a marked decrease in translation termination efficiency, which permits decoding of translation termination signals and, presumably, the production of abnormally extended polypeptides. We have examined whether the [PSI+]-induced expression of such an altered proteome might confer some selective growth advantage over [psi-] strains. Although otherwise isogenic [PSI+] and [psi-] strains show no difference in growth rates under normal laboratory conditions, we demonstrate that [PSI+] strains do exhibit enhanced tolerance to heat and chemical stress, compared with [psi-] strains. Moreover, we also show that the prion-like determinant [PSI+] is able to regulate translation termination efficiency in response to environmental stress, since growth in the presence of ethanol results in a transient increase in the efficiency of translation termination and a loss of the [PSI+] phenotype. We present a model to describe the prion-mediated regulation of translation termination efficiency and discuss its implications in relation to the potential physiological role of prions in S.cerevisiae and other fungi.
IN Während Hefe vom durch Prion-ähnliche Amyloide gekennzeichneten Typ (PSI+) unter normalen Laborbedingungen genauso gut wie der normale Typ (psi(-)) wächst, erweist sich dieser außerdem durch eine weniger effektive Translationstermination gekennzeichnete Subtyp als besonders resistent gegen Hitze und chemischen Streß. Dieser nicht-genetisch vererbbare (PSI+)-Phänotyp kann durch Anwesenheit von Alkohol in den normalen (psi(-))-Phänotyp mit strikter Translationstermination überführt werden.
ZR 41
MH Fungal Proteins/*genetics; Genes, Fungal; Heat; Models, Biological; Phenotype; Prions/*genetics; Saccharomyces cerevisiae/*genetics/growth & development; Support, Non-U.S. Gov't; Suppression, Genetic; *Translation, Genetic
AD Research School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK
SP englisch
PO England