PARENT SESSION

HA4 Ecotoxicogenomics
204 Oregon Ballroom
8:00 AM - 12:00 PM, Thursday

() Screening of genes with altered expression by environmental contaminants in cormorant liver with a microarray.

Nakayama, K¹, Iwata, H¹, Kim, E-Y², Kubota, A¹, Tashiro, K³, Tanabe, S¹, ¹ Center for Marine Environmental Studies, Ehime University, Matsuyama, Ehime, Japan² Ehime Prefectural Institute of Public Health and Environmental Science, Matsuyama, Ehime, Japan³ Division of Bioresource and Bioenvironmental Sciences, Kyushu University, Fukuoka, Fukuoka, Japan

ABSTRACT- To establish a monitoring system for gene expression profiles related to chemical contamination in wild common cormorant (Phalacrocorax carbo), the present study constructed an oligo array designed from EST sequences of the cormorant liver, which arrayed 1061 unique oligonucleotides. Using this oligo array, gene expression profiles in the liver of cormorant collected from Lake Biwa in May 2001 and May 2002 were evaluated. To detect genes in which expression patterns were altered by environmental contaminants, this study analyzed relationships between each gene expression level and concentrations of dioxins, organochlorines, butyltins and bisphenol A in the cormorant liver. Results of analyses exhibited that total 2,3,7,8-TCDD toxic equivalent (TEQ) level was positively correlated with expression levels of cytochrome P450 (CYP) 1A-like genes. However, expressions of other CYP genes including CYP2C, 2J, and 2K showed no correlation with TEQ level. CYP2C expression level was positively correlated with HCH levels. Butyltins revealed significant correlation with ubiquinol-cytochrome C reductase. In addition, 11 more genes screened were significantly correlated with any one of the environmental contaminants. Expression levels of those genes were further confirmed by real-time RT-PCR. Thus, the present study succeeded in illustrating the relationships between contaminant levels and gene expression profiles using an oligo array. The cormorant oligo array may be a useful monitoring tool to identify specific gene expression profiles altered by various environmental contaminants.

Key words: common cormorant, oligo array, environmental contaminants, toxicogenomics