Hypoxia-inducible factor 1 transcriptional complex (HIF-1) (HIF-1)

The Hypoxia-inducible factor 1 (HIF-1) transcriptional complex is a master regulator of the cellular response to low oxygen levels (hypoxia) (PMID: 22833175). It is a heterodimer composed of an oxygen-sensitive alpha subunit (HIF-1alpha) and a constitutively expressed beta subunit (HIF-1beta), also known as the aryl hydrocarbon receptor nuclear translocator (ARNT) (UniProt: P40337, P27540). Under normoxic conditions, HIF-1alpha is hydroxylated by prolyl hydroxylase domain (PHD) enzymes, leading to its recognition by the von Hippel-Lindau (VHL) protein and subsequent proteasomal degradation (StatPearls: NBK546664). In hypoxic environments, HIF-1alpha stabilizes and translocates to the nucleus, where it dimerizes with HIF-1beta to bind hypoxia-response elements (HREs) in the promoters of target genes (PubMed: 28245167). This complex activates the transcription of genes essential for angiogenesis (e.g., VEGF), glucose metabolism (e.g., GLUT1), and erythropoiesis (e.g., EPO) (PMID: 22833175). In cancer, the HIF-1 complex is often overexpressed, driving tumor progression, metabolic reprogramming, and resistance to therapy (PubMed: 30241163). Conversely, pharmacological stabilization of HIF-1 via PHD inhibitors is used to treat anemia in chronic kidney disease by stimulating endogenous erythropoietin production (PMID: 31166680).

Other names

HIF-1Hypoxia-inducible factor 1HIF1 complexHIF-1alpha/HIF-1beta complexHIF1A/ARNT complex

The mechanism of action for drugs targeting the HIF-1 complex involves either the inhibition of HIF-1alpha protein synthesis, stabilization, or DNA binding to suppress tumor-promoting genes (PMID: 30241163), or the inhibition of prolyl hydroxylase (PHD) enzymes to prevent the degradation of HIF-1alpha, thereby promoting the expression of erythropoietic and angiogenic genes (PMID: 31166680).