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Updated: Oct 18, 2025
09:17
Co-immunoprecipitation Assay Using Endogenous Nuclear Proteins from Cells Cultured Under Hypoxic Conditions
Published on: August 2, 2018
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HIF1α stabilization in hypoxia is not oxidant-initiated
Amit Kumar1,2,3, Manisha Vaish1,4, Saravanan S Karuppagounder1,2,3
1Burke Neurological Institute, White Plains, New York, United States.
Elife
|October 1, 2021
Summary
Mitochondria regulate hypoxic adaptation via HIF1α stability. This study found peroxide signaling is not essential, suggesting mitochondria primarily act as oxygen consumers in this process.
Area of Science:
- Cellular biology
- Biochemistry
- Physiology
Background:
- Mitochondria are crucial for hypoxic adaptation, influencing HIF1α stability.
- Two models propose mitochondria regulate HIF1α stability by consuming oxygen or producing peroxide.
Purpose of the Study:
- To investigate the role of peroxide in regulating HIF1α stability during hypoxia.
- To determine if reactive oxygen species (ROS) are necessary for HIF1α stabilization.
Main Methods:
- Utilized a ratiometric peroxide reporter (HyPer) to measure peroxide levels.
- Assessed the impact of antioxidant enzyme expression on HIF1α stability.
- Examined the effects of decreasing specific ROS (lipid peroxides, superoxide) on HIF1α stability.
Main Results:
- Peroxide levels did not increase, nor were antioxidant enzymes homeostatically induced in hypoxia.
- Modulating peroxide levels via antioxidant enzymes had varied effects on HIF1α stability.
- Reducing lipid peroxides or mitochondrial superoxide did not affect HIF1α stability.
Conclusions:
- Mitochondrial, cytosolic, or lipid ROS are not required for HIF1α stability.
- The findings support a model where mitochondria contribute to hypoxic adaptation mainly by consuming oxygen.
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