Transient inhibition of translation initiation by osmotic stress.
Cells respond and adapt to changes in the environment. In this study, we examined the effect of environmental stresses on protein synthesis in the yeast Saccharomyces cerevisiae. We found that osmotic stress causes irreversible inhibition of methionine uptake, transient inhibition of uracil uptake, transient stimulation of glucose uptake, transient repression of ribosomal protein (RP) genes such as CYH2 and RPS27, and the transient inhibition of translation initiation. Rapid inhibition of translation initiation by osmotic stress requires a novel pathway, different from the amino acid-sensing pathway, the glucose-sensing pathway, and the TOR pathway. The Hog1 MAP kinase pathway is not involved in the inhibition of either methionine uptake or translation initiation but is required for the adaptation of translation initiation after inhibition and the repression of RP genes by osmotic stress. These results suggest that the transient inhibition of translation initiation occurs as a result of a combination of both acute inhibition of translation and the long-term activation of translation by the Hog1 pathway.
Uesono
Yukifumi
Y
Department of Biological Sciences, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan. uesono@biol.s.u-tokyo.ac.jp
Toh-E
Akio
A
D015152:Blotting, Northern; D004305:Dose-Response Relationship, Drug; D020935:MAP Kinase Signaling System; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D009154:Mutation; D009997:Osmotic Pressure; D010957:Plasmids / Q000378:metabolism; D011132:Polyribosomes / Q000378:metabolism; D014176:Protein Biosynthesis; D012270:Ribosomes / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013997:Time Factors
D029701:Saccharomyces cerevisiae Proteins; C088589:HOG1 protein, S cerevisiae; D020928:Mitogen-Activated Protein Kinases