title: Structural basis for the recognition of hydroxyproline in HIF-1 alpha by pVHL.
abstract: Hypoxia-inducible factor-1 (HIF-1) is a transcriptional complex that controls cellular and systemic homeostatic responses to oxygen availability. HIF-1 alpha is the oxygen-regulated subunit of HIF-1, an alpha beta heterodimeric complex. HIF-1 alpha is stable in hypoxia, but in the presence of oxygen it is targeted for proteasomal degradation by the ubiquitination complex pVHL, the protein of the von Hippel Lindau (VHL) tumour suppressor gene and a component of an E3 ubiquitin ligase complex. Capture of HIF-1 alpha by pVHL is regulated by hydroxylation of specific prolyl residues in two functionally independent regions of HIF-1 alpha. The crystal structure of a hydroxylated HIF-1 alpha peptide bound to VCB (pVHL, elongins C and B) and solution binding assays reveal a single, conserved hydroxyproline-binding pocket in pVHL. Optimized hydrogen bonding to the buried hydroxyprolyl group confers precise discrimination between hydroxylated and unmodified prolyl residues. This mechanism provides a new focus for development of therapeutic agents to modulate cellular responses to hypoxia.
authors.affiliation: Division of Structural Biology, Henry Wellcome Building of Genomic Medicine, Roosevelt Drive, Oxford OX3 7BN, UK.
authors.forename: Wai-Ching
authors.initials: WC
authors.lastname: Hon
authors.forename: Michael I
authors.initials: MI
authors.lastname: Wilson
authors.forename: Karl
authors.initials: K
authors.lastname: Harlos
authors.forename: Timothy D W
authors.initials: TD
authors.lastname: Claridge
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Schofield
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Pugh
authors.forename: Patrick H
authors.initials: PH
authors.lastname: Maxwell
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Ratcliffe
authors.forename: David I
authors.initials: DI
authors.lastname: Stuart
authors.forename: E Yvonne
authors.initials: EY
authors.lastname: Jones
mesh_terms: D020816:Amino Acid Motifs; D000595:Amino Acid Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D000075065:Elongin; D006801:Humans; D006860:Hydrogen Bonding; D006900:Hydroxylation; D006909:Hydroxyproline / Q000378:metabolism*; D000860:Hypoxia / Q000378:metabolism; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007700:Kinetics; D008025:Ligases / Q000737:chemistry* / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011485:Protein Binding; D011487:Protein Conformation; D016415:Sequence Alignment; D013329:Structure-Activity Relationship; D013379:Substrate Specificity; D020349:Surface Plasmon Resonance; D014157:Transcription Factors / Q000737:chemistry* / Q000378:metabolism*; D025521:Tumor Suppressor Proteins; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein
chemical_list: D000075065:Elongin; C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D008025:Ligases; C497446:VHL protein, human; D006909:Hydroxyproline