Passing the baton: the HIF switch.

Department of Experimental Therapeutics, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA.
Trends in Biochemical Sciences (Impact Factor: 13.08). 07/2012; 37(9):364-72. DOI: 10.1016/j.tibs.2012.06.004
Source: PubMed

ABSTRACT Hypoxia is an inadequate oxygen supply to tissues and cells, which can restrict their function. The hypoxic response is primarily mediated by the hypoxia-inducible transcription factors, HIF-1 and HIF-2, which have both overlapping and unique target genes. HIF target gene activation is highly context specific and is not a reliable indicator of which HIF-α isoform is active. For example, in some cell lines, the individual HIFs have specific temporal and functional roles: HIF-1 drives the initial response to hypoxia (<24h) and HIF-2 drives the chronic response (>24h). Here, we review the significance of the HIF switch and the relation between HIF-1 and HIF-2 under both physiological and pathophysiological conditions.

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