Modulation of glucokinase expression by hypoxia-inducible factor 1 and upstream stimulatory factor 2 in primary rat hepatocytes
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U. Roth
Abstract
Glucokinase (GK) is the key enzyme of glucose utilization in liver and is localized in the less aerobic perivenous area. Until now, the O2-responsive elements in the liverspecific GK promoter are unknown, and therefore the aim of this study was to identify the O2-responsive element in this promoter. We found that the GK promoter sequence -87/-80 matched the binding site for hypoxia inducible factor 1 (HIF-1) and upstream stimulatory factor (USF). In primary rat hepatocytes we could show that venous pO2 enhanced HIF-1α and USF-2a levels, both of which activated GK expression. Furthermore, transfection experiments revealed that the GK sequence -87/-80 mediated the HIF-1α or USF-2-dependent activation of the GK promoter. The binding of HIF-1 and USF to the GKHRE was corroborated by electrophoretic mobility shift assay (EMSA). However, the maximal response to HIF-1α or USF was only achieved when constructs with the -87/ -80 sequence in context with a 39-36 bp native GK promoter sequence containing a hepatocyte nuclear factor 4 (HNF-4) binding site were used. HIF-1α and HNF-4 additively activated the GK promoter, while USF-2 and HNF-4 together did not show this additive activation. Thus, HIF-1 and USF may play differential roles in the modulation of GK expression in response to O2.
Copyright © 2004 by Walter de Gruyter GmbH & Co. KG
Articles in the same Issue
- Oxygen and the Cell
- O2 sensing in the human ductus arteriosus: redox-sensitive K+ channels are regulated by mitochondria-derived hydrogen peroxide
- Oxidative stress in the systemic and cellular responses to intermittent hypoxia
- HIF hydroxylation and cellular oxygen sensing
- Visualization of the three-dimensional organization of hypoxia-inducible factor-1α and interacting cofactors in subnuclear structures
- Modulation of glucokinase expression by hypoxia-inducible factor 1 and upstream stimulatory factor 2 in primary rat hepatocytes
- Redox-sensitive regulation of the HIF pathway under non-hypoxic conditions in pulmonary artery smooth muscle cells
- Measurement of exhaled hydrogen peroxide from rabbit lungs
- Effects of reducing agents on glutathione metabolism and the function of carotid body chemoreceptor cells
- Expression of functional purinergic receptors in pulmonary neuroepithelial bodies and their role in hypoxia chemotransmission
- Remodelling of Ca2+ homeostasis in type I cortical astrocytes by hypoxia: evidence for association with Alzheimer's disease
- Simultaneous exposure of rats to dioxin and carbon monoxide reduces the xenobiotic but not the hypoxic response
- Structure and expression of two kininogen genes in mice
- The central domain of the matrix protein of HIV-1: influence on protein structure and virus infectivity
- Skin secretion of the toad Bombina variegata contains multiple insulin-releasing peptides including bombesin and entirely novel insulinotropic structures
- Inhibition of lentil copper/TPQ amine oxidase by the mechanism-based inhibitor derived from tyramine
- Enhanced expression of basolateral multidrug resistance protein isoforms Mrp3 and Mrp5 in rat liver by LPS
- Critical O2 and NO concentrations in NO-induced cell death in a rat liver sinusoidal endothelial cell line
Articles in the same Issue
- Oxygen and the Cell
- O2 sensing in the human ductus arteriosus: redox-sensitive K+ channels are regulated by mitochondria-derived hydrogen peroxide
- Oxidative stress in the systemic and cellular responses to intermittent hypoxia
- HIF hydroxylation and cellular oxygen sensing
- Visualization of the three-dimensional organization of hypoxia-inducible factor-1α and interacting cofactors in subnuclear structures
- Modulation of glucokinase expression by hypoxia-inducible factor 1 and upstream stimulatory factor 2 in primary rat hepatocytes
- Redox-sensitive regulation of the HIF pathway under non-hypoxic conditions in pulmonary artery smooth muscle cells
- Measurement of exhaled hydrogen peroxide from rabbit lungs
- Effects of reducing agents on glutathione metabolism and the function of carotid body chemoreceptor cells
- Expression of functional purinergic receptors in pulmonary neuroepithelial bodies and their role in hypoxia chemotransmission
- Remodelling of Ca2+ homeostasis in type I cortical astrocytes by hypoxia: evidence for association with Alzheimer's disease
- Simultaneous exposure of rats to dioxin and carbon monoxide reduces the xenobiotic but not the hypoxic response
- Structure and expression of two kininogen genes in mice
- The central domain of the matrix protein of HIV-1: influence on protein structure and virus infectivity
- Skin secretion of the toad Bombina variegata contains multiple insulin-releasing peptides including bombesin and entirely novel insulinotropic structures
- Inhibition of lentil copper/TPQ amine oxidase by the mechanism-based inhibitor derived from tyramine
- Enhanced expression of basolateral multidrug resistance protein isoforms Mrp3 and Mrp5 in rat liver by LPS
- Critical O2 and NO concentrations in NO-induced cell death in a rat liver sinusoidal endothelial cell line
