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Jie Gu

Bio: Jie Gu is an academic researcher from Harvard University. The author has contributed to research in topics: Transactivation & Hypoxia-inducible factors. The author has an hindex of 1, co-authored 1 publications receiving 2036 citations.

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Journal ArticleDOI
TL;DR: The identification of an oxygen-dependent degradation (ODD) domain within HIF-1alpha that controls its degradation by the ubiquitin-proteasome pathway is reported and may provide a means of controlling gene expression by changes in oxygen tension.
Abstract: Hypoxia induces a group of physiologically important genes such as erythropoietin and vascular endothelial growth factor. These genes are transcriptionally up-regulated by hypoxia-inducible factor 1 (HIF-1), a global regulator that belongs to the basic helix-loop-helix PAS family. Although HIF-1 is a heterodimer composed of α and β subunits, its activity is primarily determined by hypoxia-induced stabilization of HIF-1α, which is otherwise rapidly degraded in oxygenated cells. We report the identification of an oxygen-dependent degradation (ODD) domain within HIF-1α that controls its degradation by the ubiquitin-proteasome pathway. The ODD domain consists of ≈200 amino acid residues, located in the central region of HIF-1α. Because portions of the domain independently confer degradation of HIF-1α, deletion of this entire region is required to give rise to a stable HIF-1α, capable of heterodimerization, DNA-binding, and transactivation in the absence of hypoxic signaling. Conversely, the ODD domain alone confers oxygen-dependent instability when fused to a stable protein, Gal4. Hence, the ODD domain plays a pivotal role for regulating HIF-1 activity and thereby may provide a means of controlling gene expression by changes in oxygen tension.

2,113 citations


Cited by
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Journal ArticleDOI
TL;DR: There is growing evidence that aging involves, in addition, progressive changes in free radical-mediated regulatory processes that result in altered gene expression.
Abstract: At high concentrations, free radicals and radical-derived, nonradical reactive species are hazardous for living organisms and damage all major cellular constituents. At moderate concentrations, how...

9,131 citations

Journal ArticleDOI
TL;DR: This review summarizes the current state of knowledge of the functions of NOX enzymes in physiology and pathology.
Abstract: For a long time, superoxide generation by an NADPH oxidase was considered as an oddity only found in professional phagocytes. Over the last years, six homologs of the cytochrome subunit of the phag...

5,873 citations

Journal ArticleDOI
20 Apr 2001-Science
TL;DR: It is shown that the interaction between human pVHL and a specific domain of the HIF-1α subunit is regulated through hydroxylation of a proline residue by an enzyme the authors have termed Hif-α prolyl-hydroxylase (HIF-PH).
Abstract: Hypoxia-inducible factor (HIF) is a transcriptional complex that plays a central role in the regulation of gene expression by oxygen. In oxygenated and iron replete cells, HIF-alpha subunits are rapidly destroyed by a mechanism that involves ubiquitylation by the von Hippel-Lindau tumor suppressor (pVHL) E3 ligase complex. This process is suppressed by hypoxia and iron chelation, allowing transcriptional activation. Here we show that the interaction between human pVHL and a specific domain of the HIF-1alpha subunit is regulated through hydroxylation of a proline residue (HIF-1alpha P564) by an enzyme we have termed HIF-alpha prolyl-hydroxylase (HIF-PH). An absolute requirement for dioxygen as a cosubstrate and iron as cofactor suggests that HIF-PH functions directly as a cellular oxygen sensor.

5,186 citations

Journal ArticleDOI
20 May 1999-Nature
TL;DR: It is indicated that the interaction between HIF-1 and pVHL is iron dependent, and that it is necessary for the oxygen-dependent degradation of HIF α-subunits, which may underlie the angiogenic phenotype of VHL-associated tumours.
Abstract: Hypoxia-inducible factor-1 (HIF-1) has a key role in cellular responses to hypoxia, including the regulation of genes involved in energy metabolism, angiogenesis and apoptosis. The alpha subunits of HIF are rapidly degraded by the proteasome under normal conditions, but are stabilized by hypoxia. Cobaltous ions or iron chelators mimic hypoxia, indicating that the stimuli may interact through effects on a ferroprotein oxygen sensor. Here we demonstrate a critical role for the von Hippel-Lindau (VHL) tumour suppressor gene product pVHL in HIF-1 regulation. In VHL-defective cells, HIF alpha-subunits are constitutively stabilized and HIF-1 is activated. Re-expression of pVHL restored oxygen-dependent instability. pVHL and HIF alpha-subunits co-immunoprecipitate, and pVHL is present in the hypoxic HIF-1 DNA-binding complex. In cells exposed to iron chelation or cobaltous ions, HIF-1 is dissociated from pVHL. These findings indicate that the interaction between HIF-1 and pVHL is iron dependent, and that it is necessary for the oxygen-dependent degradation of HIF alpha-subunits. Thus, constitutive HIF-1 activation may underlie the angiogenic phenotype of VHL-associated tumours. The pVHL/HIF-1 interaction provides a new focus for understanding cellular oxygen sensing.

4,845 citations

Journal ArticleDOI
05 Oct 2001-Cell
TL;DR: Direct modulation of recombinant enzyme activity by graded hypoxia, iron chelation, and cobaltous ions mirrors the characteristics of HIF induction in vivo, fulfilling requirements for these enzymes being oxygen sensors that regulate HIF.

3,188 citations