title: Modeling dioxygenase enzyme kinetics in familial paraganglioma.
abstract: Hypoxia inducible factors (HIFs) play vital roles in cellular maintenance of oxygen homeostasis. These transcription factors are responsible for the expression of genes involved in angiogenesis, metabolism, and cell proliferation. Here, we generate a detailed mathematical model for the enzyme kinetics of α-ketoglutarate-dependent HIF prolyl 4-hydroxylase domain (PHD) dioxygenases to simulate our in vitro data showing synergistic PHD inhibition by succinate and hypoxia in experimental models of succinate dehydrogenase loss, which phenocopy familial paraganglioma. Our mathematical model confirms the inhibitory synergy of succinate and hypoxia under physiologically-relevant conditions. In agreement with our experimental data, the model predicts that HIF1α is not stabilized under atmospheric oxygen concentrations, as observed. Further, the model confirms that addition of α-ketoglutarate can reverse PHD inhibition by succinate and hypoxia in SDH-deficient cells.
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, 200 First St. SW, Rochester, MN 55905, USA.
authors.forename: Justin P
authors.initials: JP
authors.lastname: Peters
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, 200 First St. SW, Rochester, MN 55905, USA.
authors.forename: Yeng F
authors.initials: YF
authors.lastname: Her
authors.affiliation: Department of Biochemistry and Molecular Biology, Mayo Clinic College of Medicine, 200 First St. SW, Rochester, MN 55905, USA maher@mayo.edu.
authors.forename: L James
authors.initials: LJ
authors.lastname: Maher
keywords: HIF; Hypoxia; Mathematical model; PHD; Paraganglioma