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Independent function of two destruction domains in hypoxia-inducible factor-alpha chains activated by prolyl hydroxylation.

N Masson·C Willam·P H Maxwell·C W Pugh·P J Ratcliffe
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Abstract

Oxygen-dependent proteolytic destruction of hypoxia-inducible factor-alpha (HIF-alpha) subunits plays a central role in regulating transcriptional responses to hypoxia. Recent studies have defined a key function for the von Hippel-Lindau tumour suppressor E3 ubiquitin ligase (VHLE3) in this process, and have defined an interaction with HIF-1 alpha that is regulated by prolyl hydroxylation. Here we show that two independent regions within the HIF-alpha oxygen-dependent degradation domain (ODDD) are targeted for ubiquitylation by VHLE3 in a manner dependent upon prolyl hydroxylation. In a series of in vitro and in vivo assays, we demonstrate the independent and non-redundant operation of each site in regulation of the HIF system. Both sites contain a common core motif, but differ both in overall sequence and in the conditions under which they bind to the VHLE3 ligase complex. The definition of two independent destruction domains implicates a more complex system of pVHL-HIF-alpha interactions, but reinforces the role of prolyl hydroxylation as an oxygen-dependent destruction signal.

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Amino Acid MotifsAmino Acid SequenceAnimalsBinding SitesCattleCell ExtractsConserved SequenceCytoplasmDNA-Binding ProteinsHydroxylationHypoxia-Inducible Factor 1Hypoxia-Inducible Factor 1, alpha SubunitLigasesMiceMolecular Sequence DataNuclear ProteinsProlineProtein Structure, TertiaryProteinsSequence Homology, Amino AcidTranscription FactorsTumor Suppressor ProteinsUbiquitin-Protein LigasesUbiquitinsVon Hippel-Lindau Tumor Suppressor ProteinJournal ArticleResearch Support, Non-U.S. Gov't

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N Masson, C Willam, P H Maxwell, C W Pugh, P J Ratcliffe. 2001-09-17. Independent function of two destruction domains in hypoxia-inducible factor-alpha chains activated by prolyl hydroxylation.. https://doi.org/10.1093/emboj%2F20.18.5197

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