Energy and Sugar Signaling during Hypoxia

The major consequence of hypoxia is a dramatic reduction in energy production. At the onset ofhypoxia, both oxygen and ATP availability decrease. Oxygen and energy sensing thereforeconverge to induce an adaptive response at both the transcriptional and translational levels.Oxygensensingresultsinstabilizationofthetranscriptionfactorsthatactivatehypoxia-responsegenes, including enzymes required for efficient sugar metabolism, allowing plants to produceenough energy to ensure survival. The translation ofthe resulting mRNAs is mediated by SnRK1,acting as an energy sensor. However, as soon as the sugar availability decreases, a homeostaticmechanism, detecting sugar starvation, dampens the hypoxia-dependent transcription toreduce energy consumption and preserves carbon reserves for regrowth when oxygenavailability is restored.