Construction of reporter yeasts for mouse aryl hydrocarbon receptor ligand activity.
Aryl hydrocarbons such as dioxins, polychlorinated biphenyls and polyaromatic hydrocarbons bind to the cellular aryl hydrocarbon receptor (AhR) in the initial step of their metabolism. The activation of intracellular signaling subsequent to the AhR binding is highly correlated with the toxicity and carcinogenicity of these chemicals. We produced Saccharomyces cerevisiae coexpressing mouse AhR and aryl hydrocarbon receptor nuclear translocator (Arnt) protein in accordance with Miller III's method for constructing yeasts with human Ahr and Arnt [Toxicol. Appl. Pharmacol. 160 (1998) 297]. Ligand treatment induced a dose-dependent increase in beta-galactosidase activity from a reporter plasmid in the yeast. Then, we compared activities of several ligands in yeast having the mouse Ahr/Arnt genes with those in yeast having the human genes, both of which have the same genetic background. There was no significant difference in the EC50 values of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), benzo[a]pyrene, 3-methylcholanthrene and beta-naphthoflavone between the mouse and human genes. However, indirubin, which was recently found in human urine as a potent AhR ligand [J. Biol. Chem. 276 (2001) 31475], had a 35-140 times higher EC50 value in the yeast with human genes than mouse genes. This difference might reflect species-specificity between mouse and human AhR/Arnt.
Kawanishi
Masanobu
M
Division of Radiobiology and Environmental Science, Research Institute for Advanced Science and Technology, Osaka Prefecture University, 1-2 Gakuen-cho, Sakai 599-8570, Japan.
Sakamoto
Michiyo
M
Ito
Akihide
A
Kishi
Kyoko
K
Yagi
Takashi
T
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D001580:Benzopyrenes / Q000494:pharmacology; D004268:DNA-Binding Proteins; D004785:Environmental Pollutants / Q000494:pharmacology; D017930:Genes, Reporter; D006131:Growth Inhibitors / Q000494:pharmacology; D018257:Helix-Loop-Helix Motifs; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D008024:Ligands; D008748:Methylcholanthrene / Q000494:pharmacology; D051379:Mice; D010957:Plasmids; D000072317:Polychlorinated Dibenzodioxins / Q000494:pharmacology; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D001616:beta-Galactosidase / Q000378:metabolism; D019324:beta-Naphthoflavone / Q000494:pharmacology
C497396:ARNT protein, human; D000903:Antibiotics, Antineoplastic; C497397:Arnt protein, mouse; D001580:Benzopyrenes; D004268:DNA-Binding Proteins; D004785:Environmental Pollutants; D006131:Growth Inhibitors; D007211:Indoles; D008024:Ligands; D000072317:Polychlorinated Dibenzodioxins; D018336:Receptors, Aryl Hydrocarbon; D014157:Transcription Factors; D051784:Aryl Hydrocarbon Receptor Nuclear Translocator; D008748:Methylcholanthrene; D019324:beta-Naphthoflavone; D001616:beta-Galactosidase; C027185:indirubin