Hypoxia-inducible factors in the kidney.
Tissue hypoxia not only occurs under pathological conditions but is also an important microenvironmental factor that is critical for normal embryonic development. Hypoxia-inducible factors HIF-1 and HIF-2 are oxygen-sensitive basic helix-loop-helix transcription factors, which regulate biological processes that facilitate both oxygen delivery and cellular adaptation to oxygen deprivation. HIFs consist of an oxygen-sensitive alpha-subunit, HIF-alpha, and a constitutively expressed beta-subunit, HIF-beta, and regulate the expression of genes that are involved in energy metabolism, angiogenesis, erythropoiesis and iron metabolism, cell proliferation, apoptosis, and other biological processes. Under conditions of normal Po(2), HIF-alpha is hydroxylated and targeted for rapid proteasomal degradation by the von Hippel-Lindau (VHL) E3-ubiquitin ligase. When cells experience hypoxia, HIF-alpha is stabilized and either dimerizes with HIF-beta in the nucleus to form transcriptionally active HIF, executing the canonical hypoxia response, or it physically interacts with unrelated proteins, thereby enabling convergence of HIF oxygen sensing with other signaling pathways. In the normal, fully developed kidney, HIF-1alpha is expressed in most cell types, whereas HIF-2alpha is mainly found in renal interstitial fibroblast-like cells and endothelial cells. This review summarizes some of the most recent advances in the HIF field and discusses their relevance to renal development, normal kidney function and disease.
Haase
Volker H
VH
Renal Electrolyte and Hypertension Division, Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania 19104-6144, USA. vhaase@mail.med.upenn.edu
D000818:Animals; D017209:Apoptosis / Q000235:genetics / Q000502:physiology; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator / Q000032:analysis* / Q000235:genetics / Q000502:physiology*; D051792:Basic Helix-Loop-Helix Proteins / Q000032:analysis* / Q000235:genetics / Q000502:physiology*; D004195:Disease Models, Animal; D004920:Erythropoiesis / Q000235:genetics / Q000502:physiology; D005786:Gene Expression Regulation / Q000502:physiology; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D015972:Gene Expression Regulation, Neoplastic / Q000502:physiology; D006801:Humans; D000860:Hypoxia / Q000503:physiopathology; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000032:analysis* / Q000235:genetics / Q000502:physiology*; D007668:Kidney / Q000737:chemistry* / Q000196:embryology / Q000293:injuries / Q000502:physiology*; D007680:Kidney Neoplasms / Q000235:genetics / Q000503:physiopathology; D051379:Mice; D015398:Signal Transduction / Q000235:genetics / Q000502:physiology; D000099162:Endothelial PAS Domain-Containing Protein 1
D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D051792:Basic Helix-Loop-Helix Proteins; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D000099162:Endothelial PAS Domain-Containing Protein 1