HIF-2α-pVHL complex reveals broad genotype-phenotype correlations in HIF-2α-driven disease.
Publication Type:Journal Article
Source:Nat Commun, Volume 9, Issue 1, p.3359 (2018)
Keywords:Basic Helix-Loop-Helix Transcription Factors, Genetic Association Studies, Humans, Hypoxia-Inducible Factor 1, alpha Subunit, Kinetics, Mutation, Neuroendocrine Tumors, Polycythemia, Protein Binding, Von Hippel-Lindau Tumor Suppressor Protein
<p>It is definitively established that mutations in transcription factor HIF-2α are causative of both neuroendocrine tumors (class 1 disease) and polycythemia (class 2 disease). However, the molecular mechanism that underlies this emergent genotype-phenotype relationship has remained unclear. Here, we report the structure of HIF-2α peptide bound to pVHL-elongin B-elongin C (VBC) heterotrimeric complex, which shows topographical demarcation of class 1 and 2 mutations affecting residues predicted, and demonstrated via biophysical analyses, to differentially impact HIF-2α-pVHL interaction interface stability. Concordantly, biochemical experiments showed that class 1 mutations disrupt pVHL affinity to HIF-2α more adversely than class 2 mutations directly or indirectly via impeding PHD2-mediated hydroxylation. These findings suggest that neuroendocrine tumor pathogenesis requires a higher HIF-2α dose than polycythemia, which requires only a mild increase in HIF-2α activity. These biophysical data reveal a structural basis that underlies, and can be used to predict de novo, broad genotype-phenotype correlations in HIF-2α-driven disease.</p>