MP7 Toxicogenomics in Environmental Studies
Monday, 14 November 2005: 8:00 AM - 5:30 PM in Exhibit Hall

(KIM-1117-816780) Gene expression characteristics of Vitellogenin, Choriogenin L, Aryl Hydrocarbon Receptor, Cytochrome P450 1A and Heat Shock Protein 70 in Japanese medaka fish exposed to Endocrine Disrupting Chemicals.

Kim, H.N., Park, K.S., Gu, M.B.,

ABSTRACT- In the our previous study, the gene expression kinetics of estrogen receptor(ER), cytochrome P450 aromatase(CYP19) and p53 were examined for the representative endocrine disrupting chemicals (EDCs), 17 beta estradiol, nonylphenol and bisphenol A. Each biomarker is known by its estrogenic potential, steroidgenesis of chemicals and tumor suppression, respectively. In this study, expression kinetics of the female related genes and other cellular toxicity represented genes, such as vitellogenin(yolk protein precursor), choriogenin L(inner membrane precursor of egg), aryl hydrocarbon receptor (AhR), cytochrome P450 1A (CYP1A) and heat shock protein 70(HSP70) were studied on male Japanese medaka in the presence of three EDCs. Japanese medaka was exposed to 100ppb and 1ppb of 17 beta estradiol, 75ppb and 7.5ppb of nonylphenol and 75ppb and 7.5ppb of bisphenol A. The highest concentration tested with each chemical was LC 20 value obtained from acute toxicity test on young Japanese medaka. The fish livers were extracted after 1day, 2days and 4days from exposure. Gene expressions were quantified by measurement of messenger RNA (mRNA) in liver extracts using Taqman based real time PCR method. From the expression patterns of these five genes, the different transcriptional mechanisms and the stability of the transcripts of each gene were examined for each chemical.

Key words: endocrine disrupting chemicals, real time qPCR, Japanese medaka