Ohi Hiroaki, Fujita Yoshiaki, Miyao Makiko, Saguchi Ken-ichi, Murayama Nobuhiro, Higuchi Shigesada
Laboratory of Biopharmaceutics, School of Pharmaceutical Sciences, Showa University, 1-5-8 Hatanodai, Shinagawa-ku, Tokyo 142-8555, Japan.
Biochem Biophys Res Commun. 2003 Aug 1;307(3):595-9. doi: 10.1016/s0006-291x(03)01244-0.
The aryl hydrocarbon receptor (AHR) is a member of the basic helix-loop-helix/Per-Arnt-Sim (bHLH/PAS) family of transcription factors. Although this receptor has been known to mediate the toxic effects of environmental pollutants, its physiological functions remain elusive. Here, we describe the isolation and expression pattern of the Xenopus AHR gene. The predicted amino acid sequence contained regions characteristic of other vertebrate AHRs. However, in line with previously described fish AHR genes, no distinct Q-rich domain was found. Phylogenetic analysis demonstrated that Xenopus AHR was clustered within the AHR1 clade. As in the case of mammalian AHR genes, the Xenopus AHR gene was expressed in all the adult tissues tested. Xenopus AHR was also expressed during early development, in parallel with expression of the CYP1A7 gene, which is thought to be regulated by AHR. These results suggest that while frogs are relatively tolerant to TCDD toxicity, the AHR of frogs has characteristics similar to those of other vertebrate AHRs.
芳烃受体（AHR）是转录因子基本螺旋-环-螺旋/Per-Arnt-Sim（bHLH/PAS）家族的成员。尽管已知该受体介导环境污染物的毒性作用，但其生理功能仍不清楚。在此，我们描述了非洲爪蟾AHR基因的分离和表达模式。预测的氨基酸序列包含其他脊椎动物AHR的特征区域。然而，与先前描述的鱼类AHR基因一致，未发现明显的富含Q的结构域。系统发育分析表明，非洲爪蟾AHR聚集在AHR1进化枝内。与哺乳动物AHR基因的情况一样，非洲爪蟾AHR基因在所有测试的成体组织中均有表达。非洲爪蟾AHR在早期发育过程中也有表达，与被认为受AHR调控的CYP1A7基因的表达平行。这些结果表明，虽然青蛙对2,3,7,8-四氯二苯并对二恶英（TCDD）毒性相对耐受，但青蛙的AHR具有与其他脊椎动物AHR相似的特征。
