title: pVHL modification by NEDD8 is required for fibronectin matrix assembly and suppression of tumor development.
abstract: Functional inactivation of the von Hippel-Lindau (VHL) tumor suppressor gene is the cause of the familial VHL disease and most sporadic renal clear-cell carcinomas (RCC). pVHL has been shown to play a role in the destruction of hypoxia-inducible factor alpha (HIF-alpha) subunits via ubiquitin-mediated proteolysis and in the regulation of fibronectin matrix assembly. Although most disease-causing pVHL mutations hinder the regulation of the HIF pathway, every disease-causing pVHL mutant tested to date has failed to promote the assembly of the fibronectin matrix, underscoring its potential importance in VHL disease. Here, we report that a ubiquitin-like molecule called NEDD8 covalently modifies pVHL. A nonneddylateable pVHL mutant, while retaining its ability to ubiquitylate HIF, failed to bind to and promote the assembly of the fibronectin matrix. Expression of the neddylation-defective pVHL in RCC cells, while restoring the regulation of HIF, failed to promote the differentiated morphology in a three-dimensional growth assay and was insufficient to suppress the formation of tumors in SCID mice. These results suggest that NEDD8 modification of pVHL plays an important role in fibronectin matrix assembly and that in the absence of such regulation, an intact HIF pathway is insufficient to prevent VHL-associated tumorigenesis.
authors.affiliation: Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario M5S 1A8, Canada. michael.ohh@utoronto.ca
authors.forename: Natalie H
authors.initials: NH
authors.lastname: Stickle
authors.forename: Jacky
authors.initials: J
authors.lastname: Chung
authors.forename: Jeffery M
authors.initials: JM
authors.lastname: Klco
authors.forename: Richard P
authors.initials: RP
authors.lastname: Hill
authors.forename: William G
authors.initials: WG
authors.lastname: Kaelin
authors.forename: Michael
authors.initials: M
authors.lastname: Ohh
mesh_terms: D018262:Adenocarcinoma, Clear Cell / Q000378:metabolism* / Q000473:pathology; D000818:Animals; D002455:Cell Division / Q000502:physiology; D045744:Cell Line, Tumor; D004268:DNA-Binding Proteins / Q000235:genetics / Q000378:metabolism; D005109:Extracellular Matrix / Q000737:chemistry / Q000378:metabolism*; D005353:Fibronectins / Q000378:metabolism*; D016147:Genes, Tumor Suppressor; D051272:Glucose Transporter Type 1; D006801:Humans; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D007680:Kidney Neoplasms / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D016513:Mice, SCID; D009004:Monosaccharide Transport Proteins / Q000378:metabolism; D000075687:NEDD8 Protein; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D018874:Spheroids, Cellular; D014157:Transcription Factors; D014183:Transplantation, Heterologous; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*; D025801:Ubiquitin / Q000378:metabolism; D044767:Ubiquitin-Protein Ligases / Q000235:genetics / Q000378:metabolism*; D014452:Ubiquitins / Q000235:genetics / Q000378:metabolism*; D051794:Von Hippel-Lindau Tumor Suppressor Protein; D006623:von Hippel-Lindau Disease / Q000235:genetics / Q000378:metabolism
chemical_list: D004268:DNA-Binding Proteins; D005353:Fibronectins; D051272:Glucose Transporter Type 1; C497442:HIF1A protein, human; C497443:Hif1a protein, mouse; D051793:Hypoxia-Inducible Factor 1; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D009004:Monosaccharide Transport Proteins; D000075687:NEDD8 Protein; C082860:NEDD8 protein, human; C513172:Nedd8 protein, mouse; D009687:Nuclear Proteins; C495677:SLC2A1 protein, human; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; D025801:Ubiquitin; D014452:Ubiquitins; D044767:Ubiquitin-Protein Ligases; D051794:Von Hippel-Lindau Tumor Suppressor Protein; C497446:VHL protein, human