Limited species differences in estrogen receptor alpha-medicated reporter gene transactivation by xenoestrogens.
Estrogen receptors (ERs) play an important role in estrogen function. However, it is well known that there are species differences in amino acid sequences of the ligand binding domains. Here, we report on the analysis of species differences in ER-dependent transactivation with some chemicals using reporter gene assays. Full-length ER cDNAs from human, rat, chicken, alligator (Caiman), whiptail lizard, African clawed frog and rainbow trout were prepared from hepatic mRNA by the RT-PCR method and inserted into expression plasmids. Both expression and reporter plasmids were transiently transfected into HeLa cells, and then the estrogenic effects of chemicals were analyzed in terms of induction of luciferase activity. No species differences in transactivation were found among human, rat, chicken, alligator, whiptail lizard and African clawed frog ERs. However, thermo-dependent alteration in susceptibility to 17-beta-estradiol was observed with the rainbow trout ER because of thermo-dependence of estrogen binding.
Sumida
Kayo
K
Environmental Health Science Laboratory, Sumitomo Chemical Co. Ltd., 1-98, 3-Chome, Kasugade-naka, Konohana-ku, Osaka 554-8558, Japan. sumida@sc.sumitomo-chem.co.jp
Ooe
Norihisa
N
Saito
Koichi
K
Kaneko
Hideo
H
D000489:Alligators and Crocodiles; D000595:Amino Acid Sequence; D000818:Animals; D001001:Anura; D002645:Chickens; D018076:DNA, Complementary / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D047628:Estrogen Receptor alpha; D004967:Estrogens / Q000378:metabolism*; D017930:Genes, Reporter; D005822:Genetic Vectors; D006367:HeLa Cells; D006801:Humans; D008116:Lizards; D008156:Luciferases / Q000378:metabolism; D008969:Molecular Sequence Data; D011485:Protein Binding; D017434:Protein Structure, Tertiary; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D011960:Receptors, Estrogen / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity; D013696:Temperature; D015533:Transcriptional Activation; D014162:Transfection; D014337:Trout
D018076:DNA, Complementary; D047628:Estrogen Receptor alpha; D004967:Estrogens; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D008156:Luciferases