The RNA exosome affects iron response and sensitivity to oxidative stress.
RNA degradation plays important roles for maintaining temporal control and fidelity of gene expression, as well as processing of transcripts. In Saccharomyces cerevisiae the RNA exosome is a major 3'-to-5' exoribonuclease and also has an endonuclease domain of unknown function. Here we report a physiological role for the exosome in response to a stimulus. We show that inactivating the exoribonuclease active site of Rrp44 up-regulates the iron uptake regulon. This up-regulation is caused by increased levels of reactive oxygen species (ROS) in the mutant. Elevated ROS also causes hypersensitivity to H2O2, which can be reduced by the addition of iron to H2O2 stressed cells. Finally, we show that the previously characterized slow growth phenotype of rrp44-exo(-) is largely ameliorated during fermentative growth. While the molecular functions of Rrp44 and the RNA exosome have been extensively characterized, our studies characterize how this molecular function affects the physiology of the organism.
['Tsanova|Borislava|B|', 'Spatrick|Phyllis|P|', 'Jacobson|Allan|A|', 'van Hoof|Ambro|A|']
D004351:Drug Resistance D005095:Exoribonucleases D063326:Exosome Multienzyme Ribonuclease Complex D006861:Hydrogen Peroxide D007501:Iron D053858:Metabolic Networks and Pathways D030781:Organisms, Genetically Modified D018384:Oxidative Stress D020871:RNA Stability D017382:Reactive Oxygen Species D012441:Saccharomyces cerevisiae D029701:Saccharomyces cerevisiae Proteins
RNA degradation RRP44 DIS3 yeast