NR AGYG
AU Kwapisz,M.; Smagowicz,W.J.; Oficjalska,D.; Hatin,I.; Rousset,J.P.; Oladek,T.; Boguta,M.
TI Up-regulation of tRNA biosynthesis affects translational readthrough in maf1- Delta mutant of Saccharomyces cerevisiae
QU Current Genetics 2002 Dec; 42(3): 147-52
PT journal article
AB Maf1p is a negative effector of RNA polymerase III in yeast. The maf1- Delta mutation caused an increase in the level of cellular tRNAs, but a decrease of translational readthrough at nonsense codons. Using the lacZ- luc dual gene reporter system, we detected an almost twofold diminution of UAA and UAG readthrough in maf1- Delta compared with the parental strain. The maf1- Delta mutation did not affect the rate of protein biosynthesis and growth at standard conditions, but resulted in temperature-sensitive growth on non-fermentable carbon sources. We examined the correlation of the temperature sensitive and antisuppression phenotypes of maf1- Delta using a colour phenotype assay in the ade2-1 SUP11 strain. Antisuppression, but not the temperature-sensitive growth defect, was compensated either by increased dosage of SUP11or by [ PSI(+)], the prion form of the translation termination factor Sup35p. Summarizing, the elevated tRNA levels in maf1- Delta increase translational fidelity and, independently, affect growth under special conditions.
AD Institute of Biochemistry and Biophysics, Polish Academy of Sciences, Pawinskiego 5a, 02-106 Warsaw, Poland.
SP englisch
PO USA