Repression of heme oxygenase-1 expression as a defense strategy in humans.
Heme oxygenase-1 (HO-1) is an essential enzyme in heme catabolism and is characterized by its inducibility in response to various environmental factors, including its substrate heme. The induction of HO-1 has been established as the defense mechanism against oxidative stress. However, striking interspecies or inter-tissue differences are noted in the regulation of HO-1 expression under hypoxia or heat shock, each of which represses HO-1 expression in many types of human cells but rather induces it in rodent cells. The downregulation of HO-1 expression may reduce energy expenditure and local production of carbon monoxide, iron, and bilirubin and transiently increase intracellular heme pool. Here, we discuss the repression of HO-1 expression as a potential defense strategy in humans by highlighting a regulatory role of HO-1 in its own expression.
Shibahara
Shigeki
S
Department of Molecular Biology and Applied Physiology, Tohoku University School of Medicine, Sendai 980-8575, Japan. shibahar@mail.cc.tohoku.ac.jp
Nakayama
Masaharu
M
Kitamuro
Tomomi
T
Udono-Fujimori
Reiko
R
Takahashi
Kazuhiro
K
D000818:Animals; D004268:DNA-Binding Proteins; D004734:Energy Metabolism; D051856:Fanconi Anemia Complementation Group Proteins; D015971:Gene Expression Regulation, Enzymologic; D006419:Heme Oxygenase (Decyclizing) / Q000235:genetics* / Q000378:metabolism*; D051547:Heme Oxygenase-1; D006801:Humans; D008565:Membrane Proteins; D011401:Promoter Regions, Genetic; D020365:RNA Helicases / Q000378:metabolism
D004268:DNA-Binding Proteins; D051856:Fanconi Anemia Complementation Group Proteins; D008565:Membrane Proteins; C496541:HMOX1 protein, human; D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1; C000618935:BRIP1 protein, human; D020365:RNA Helicases