title: Generation of a 'humanized' hCYP1A1_1A2_Cyp1a1/1a2(-/-)_Ahrd mouse line harboring the poor-affinity aryl hydrocarbon receptor.
abstract: Herein, we describe generation of the hCYP1A1_1A2_Cyp1a1/1a2(-/-)_Ahr(d) mouse line, which carries human functional CYP1A1 and CYP1A2 genes in the absence of mouse Cyp1a1 and Cyp1a2 genes, in a (>99.8%) background of the C57BL/6J genome and harboring the poor-affinity aryl hydrocarbon receptor (AHR) from the DBA/2J mouse. We have characterized this line by comparing it to our previously created hCYP1A1_1A2_Cyp1a1/1a2(-/-)_Ahr(b1) line-which carries the same but has the high-affinity AHR of the C57BL/6J mouse. By quantifying CYP1A1 and CYP1A2 mRNA in liver, lung and kidney of dioxin-treated mice, we show that dose-response curves in hCYP1A1_1A2_Cyp1a1/1a2(-/-)_Ahr(d) mice are shifted to the right of those in hCYP1A1_1A2_Cyp1a1/1a2(-/-)_Ahr(b1) mice-similar to, but not as robust as, dose-response curves in DBA/2J versus C57BL/6J mice. This new mouse line is perhaps more relevant than the former to human risk assessment vis-à-vis human CYP1A1 and CYP1A2 substrates, because poor-affinity rather than high-affinity AHR occurs in the vast majority of the human population.
authors.affiliation: Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, PO Box 670056, Cincinnati, OH 45267-0056, USA.
authors.forename: Zhanquan
authors.initials: Z
authors.lastname: Shi
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.forename: Hongbin
authors.initials: H
authors.lastname: Dong
authors.forename: Robyn M
authors.initials: RM
authors.lastname: Amos-Kroohs
authors.forename: Daniel W
authors.initials: DW
authors.lastname: Nebert
mesh_terms: D000818:Animals; D019363:Cytochrome P-450 CYP1A1 / Q000235:genetics*; D019388:Cytochrome P-450 CYP1A2 / Q000235:genetics*; D006801:Humans; D007668:Kidney / Q000201:enzymology; D008099:Liver / Q000201:enzymology; D008168:Lung / Q000201:enzymology; D051379:Mice; D008822:Mice, Transgenic / Q000235:genetics* / Q000378:metabolism; D018336:Receptors, Aryl Hydrocarbon / Q000235:genetics* / Q000378:metabolism
chemical_list: D018336:Receptors, Aryl Hydrocarbon; D019363:Cytochrome P-450 CYP1A1; D019388:Cytochrome P-450 CYP1A2