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Updated: Jul 7, 2026
09:45
Measuring mRNA Levels Over Time During the Yeast S. cerevisiae Hypoxic Response
Published on: August 10, 2017
Translational repression during chronic hypoxia is dependent on glucose levels
Jeff D Thomas1, Lizalynn M Dias, Gregg J Johannes
1Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, Philadelphia, Pennsylvania 19102, USA.
RNA (New York, N.Y.)
|February 13, 2008
Summary
Hypoxia represses translation, but only when glucose is depleted. Adding glucose or oxygen restores translation, revealing a dual requirement for translational control in cancer cells.
Area of Science:
- Cellular Biology
- Cancer Research
- Biochemistry
Background:
- Hypoxia is common in solid tumors and often leads to translational repression.
- Previously, prolonged hypoxia (>16 hours) was thought to be the sole trigger for this repression.
Purpose of the Study:
- To investigate the role of glucose availability in hypoxia-induced translational repression.
- To elucidate the mechanism underlying translational inhibition under combined glucose and oxygen deprivation.
Main Methods:
- Utilized PC3 cell lines under varying conditions of hypoxia and glucose availability.
- Monitored translation rates, glucose levels, and eukaryotic initiation factor 2-alpha (eIF2alpha) phosphorylation.
- Assessed the involvement of pancreatic eIF2alpha kinase (PERK) in the observed effects.
Main Results:
- Prolonged hypoxia leads to glucose depletion, which correlates with translation shutdown.
- Glucose addition or reoxygenation restored translation in hypoxic cells, indicating both factors are necessary.
- eIF2alpha phosphorylation was reversed by glucose, and this process was independent of PERK.
Conclusions:
- Glucose depletion, not just hypoxia, is essential for translational repression.
- This finding explains the prolonged exposure requirement for hypoxia-induced translational inhibition.
- Understanding the glucose-hypoxia interplay is crucial for comprehending solid tumor growth and metabolism.
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