Glucose triggers different global responses in yeast, depending on the strength of the signal, and transiently stabilizes ribosomal protein mRNAs.
Glucose exerts profound effects upon yeast physiology. In general, the effects of high glucose concentrations (>1%) upon Saccharomyces cerevisiae have been studied. In this paper, we have characterized the global responses of yeast cells to very low (0.01%), low (0.1%) and high glucose signals (1.0%) by transcript profiling. We show that yeast is more sensitive to very low glucose signals than was previously thought, and that yeast displays different responses to these different glucose signals. Genes involved in central metabolic pathways respond rapidly to very low glucose signals, whereas genes involved in the biogenesis of cytoplasmic ribosomes generally respond only to glucose concentrations of> 0.1%. We also show that cytoplasmic ribosomal protein mRNAs are transiently stabilized by glucose, indicating that both transcriptional and post-transcriptional mechanisms combine to accelerate the accumulation of ribosomal protein mRNAs. Presumably, this facilitates rapid ribosome biogenesis after exposure to glucose. However, our data indicate that yeast activates ribosome biogenesis only when sufficient glucose is available to make this metabolic investment worthwhile. In contrast, the regulation of metabolic functions in response to very low glucose signals presumably ensures that yeast can exploit even minute amounts of this preferred nutrient.
Yin
Zhikang
Z
Department of Molecular and Cell Biology, University of Aberdeen, Institute of Medical Sciences, Foresterhill, Aberdeen AB25 2ZD, UK.
Wilson
Séan
S
Hauser
Nicole C
NC
Tournu
Helene
H
Hoheisel
Jörg D
JD
Brown
Alistair J P
AJ
D002244:Carbon / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D005947:Glucose / Q000378:metabolism*; D009004:Monosaccharide Transport Proteins / Q000235:genetics / Q000378:metabolism; D016366:Open Reading Frames; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism*; D012269:Ribosomal Proteins / Q000235:genetics* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction / Q000502:physiology*
D009004:Monosaccharide Transport Proteins; D012333:RNA, Messenger; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D002244:Carbon; D005947:Glucose