Estrogen-responsive transient expression assay using a brain aromatase-based reporter gene in zebrafish (Danio rerio).
Whereas endogenous estrogens play an important role in the development, maintenance, and function of female and male reproductive organs, xenoestrogens present in the environment disrupt normal endocrine function in humans and wildlife. Various in vivo and in vitro assays have been developed to screen these xenoestrogens. However, traditional in vivo assays are laborious and unsuitable for large-scale screening, and in vitro assays do not necessarily replicate in vivo functioning. To overcome these limitations, we developed a transient expression assay in zebrafish, into which a brain aromatase (cyp19a1b)-based estrogen-responsive reporter gene was introduced. In response to 17beta-estradiol (10(-6) M) and heptachlor (10(-6) M), zebrafish embryos carrying the reporter construct expressed enhanced green fluorescent protein in the olfactory bulb, telencephalon, preoptic area, and mediobasal hypothalamus. This system will serve to model the in vivo conversion and breakdown of estrogenic compounds and thus provide a rapid preliminary screening method to estimate their estrogenicity.
Kim
Dong-Jae
DJ
Department of Laboratory Animal Medicine, College of Veterinary Medicine, and BK2 Program for Veterinary Science, Seoul National University, Seoul, South Korea.
Seok
Seung-Hyeok
SH
Baek
Min-Won
MW
Lee
Hui-Young
HY
Na
Yi-Rang
YR
Park
Sung-Hoon
SH
Lee
Hyun-Kyoung
HK
Dutta
Noton Kumar
NK
Kawakami
Koichi
K
Park
Jae-Hak
JH
D000818:Animals; D001141:Aromatase / Q000235:genetics* / Q000378:metabolism; D001681:Biological Assay; D001921:Brain / Q000187:drug effects / Q000201:enzymology*; D004625:Embryo, Nonmammalian / Q000187:drug effects / Q000201:enzymology; D052244:Endocrine Disruptors / Q000494:pharmacology; D004958:Estradiol / Q000494:pharmacology; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D017930:Genes, Reporter; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006533:Heptachlor / Q000494:pharmacology; D007306:Insecticides / Q000494:pharmacology; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism*; D014162:Transfection; D015027:Zebrafish; D029961:Zebrafish Proteins / Q000235:genetics* / Q000378:metabolism
D052244:Endocrine Disruptors; D004967:Estrogens; D007306:Insecticides; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D029961:Zebrafish Proteins; D049452:Green Fluorescent Proteins; D004958:Estradiol; D006533:Heptachlor; D001141:Aromatase; C440729:Cyp19a1a protein, zebrafish