HIF1α stabilization in hypoxia is not oxidant-initiated.
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ABSTRACT:
SUBMITTER: Kumar A
PROVIDER: S-EPMC8530508 | biostudies-literature | 2021 Oct
REPOSITORIES: biostudies-literature
Publications
HIF1α stabilization in hypoxia is not oxidant-initiated.
Kumar Amit A Vaish Manisha M Karuppagounder Saravanan S SS Gazaryan Irina I Cave John W JW Starkov Anatoly A AA Anderson Elizabeth T ET Zhang Sheng S Pinto John T JT Rountree Austin M AM Wang Wang W Sweet Ian R IR Ratan Rajiv R RR
eLife 20211001
Hypoxic adaptation mediated by HIF transcription factors requires mitochondria, which have been implicated in regulating HIF1α stability in hypoxia by distinct models that involve consuming oxygen or alternatively converting oxygen into the second messenger peroxide. Here, we use a ratiometric, peroxide reporter, HyPer to evaluate the role of peroxide in regulating HIF1α stability. We show that antioxidant enzymes are neither homeostatically induced nor are peroxide levels increased in hypoxia. ...[more]
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