HIF-1alpha binding to VHL is regulated by stimulus-sensitive proline hydroxylation

Proc Natl Acad Sci U S A. 2001 Aug 14;98(17):9630-5. doi: 10.1073/pnas.181341498.

Abstract

Hypoxia-inducible factor-1alpha (HIF-1alpha) is a global transcriptional regulator of the hypoxic response. Under normoxic conditions, HIF-1alpha is recognized by the von Hippel-Lindau tumor-suppressor protein (VHL), a component of an E3 ubiquitin ligase complex. This interaction thereby promotes the rapid degradation of HIF-1alpha. Under hypoxic conditions, HIF-1alpha is stabilized. We have previously shown that VHL binds in a hypoxia-sensitive manner to a 27-aa segment of HIF-1alpha, and that this regulation depends on a posttranslational modification of HIF-1alpha. Through a combination of in vivo coimmunoprecipitation assays using VHL and a panel of point mutants of HIF-1alpha in this region, as well as MS and in vitro binding assays, we now provide evidence that this modification, which occurs under normoxic conditions, is hydroxylation of Pro-564 of HIF-1alpha. The data furthermore show that this proline hydroxylation is the primary regulator of VHL binding.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Animals
  • COS Cells
  • Cell Hypoxia
  • Chlorocebus aethiops
  • Cobalt / pharmacology
  • DNA-Binding Proteins / metabolism*
  • HeLa Cells
  • Humans
  • Hydroxylation
  • Hydroxyproline / chemistry
  • Hydroxyproline / physiology*
  • Hypoxia-Inducible Factor 1
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Ligases*
  • Macromolecular Substances
  • Molecular Sequence Data
  • Nuclear Proteins / metabolism*
  • Peptide Fragments / metabolism
  • Point Mutation
  • Proline / chemistry
  • Protein Binding / drug effects
  • Protein Processing, Post-Translational*
  • Proteins / genetics
  • Proteins / metabolism*
  • Recombinant Fusion Proteins / chemistry
  • Recombinant Fusion Proteins / metabolism
  • Transcription Factors*
  • Transfection
  • Tumor Suppressor Proteins*
  • Ubiquitin-Protein Ligases*
  • Von Hippel-Lindau Tumor Suppressor Protein

Substances

  • DNA-Binding Proteins
  • HIF1A protein, human
  • Hypoxia-Inducible Factor 1
  • Hypoxia-Inducible Factor 1, alpha Subunit
  • Macromolecular Substances
  • Nuclear Proteins
  • Peptide Fragments
  • Proteins
  • Recombinant Fusion Proteins
  • Transcription Factors
  • Tumor Suppressor Proteins
  • Cobalt
  • Proline
  • Ubiquitin-Protein Ligases
  • Von Hippel-Lindau Tumor Suppressor Protein
  • Ligases
  • VHL protein, human
  • Hydroxyproline