Effect of protein kinase and phosphatase inhibitors on expression of hypoxia-inducible factor 1

Biochem Biophys Res Commun. 1995 Nov 13;216(2):669-75. doi: 10.1006/bbrc.1995.2674.


Hypoxia-inducible factor 1 (HIF-1) is a heterodimeric bHLH-PAS protein essential for erythropoietin gene transcription in hypoxic cells. Here we show that both 2-aminopurine and sodium fluoride, inhibitors of serine/threonine kinases and phosphatases, respectively, interfered with the hypoxic induction of HIF-1 DNA-binding activity and expression of HIF-1 alpha and HIF-1 beta(ARNT) subunits. Genistein, an inhibitor of tyrosine kinases, completely blocked the synthesis of both HIF-1 subunits as well as HIF-1 DNA-binding activity. Sodium orthovanadate, an inhibitor of tyrosine phosphatases increased the basal level of HIF-1 proteins and HIF-1 activity. These data suggest that protein phosphorylation events play an important role in the hypoxia signal-transduction pathway that leads to synthesis of HIF-1 alpha and HIF-1 beta proteins and the induction of HIF-1 DNA-binding activity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • 2-Aminopurine / pharmacology*
  • Cell Line
  • Cell Nucleus / drug effects
  • Cell Nucleus / metabolism
  • DNA-Binding Proteins / biosynthesis*
  • DNA-Binding Proteins / isolation & purification
  • Enzyme Inhibitors / pharmacology*
  • Gene Expression / drug effects*
  • Humans
  • Hypoxia-Inducible Factor 1
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Immunoblotting
  • Nuclear Proteins / biosynthesis*
  • Nuclear Proteins / isolation & purification
  • Protein Kinase Inhibitors*
  • Protein Tyrosine Phosphatases / antagonists & inhibitors*
  • Sodium Fluoride / pharmacology*
  • Transcription Factors / biosynthesis*
  • Transcription, Genetic / drug effects
  • Tumor Cells, Cultured


  • DNA-Binding Proteins
  • Enzyme Inhibitors
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Nuclear Proteins
  • Protein Kinase Inhibitors
  • Transcription Factors
  • 2-Aminopurine
  • Sodium Fluoride
  • Protein Tyrosine Phosphatases