Glutathione S-transferase 유전자의 클로닝

Abstract

Glutathione S-transferase (GST) is a family of enzymes that utilize glutathione in reactions contributing to the transformation of a wide range of compounds, including carcinogens, therapeutic drugs, and products of oxidative stress.1) This enzyme plays a key role in the detoxification of such substances2) and the gene expression changes are useful to monitor toxicant exposure as a biomarker. We designed GST targeted primers from highly conserved region of glutathione s-transferase gene in various organisms and have cloned using RT-PCR with RNA extracted from rockfish liver. Also we cloned CYP1A1 gene as a good indicator for exposure to toxicants and followed the molecular aspects in fish exposed to benzo[a]pyrene (BaP), representative ecotoxicant, comparing with the gene expression profiles of GST. The four groups of rockfish were exposed to BaP (1 μM) for 0, 6, 12, 24 hr then total RNAs were extracted from livers. The gene expression changes of CYP1A1 and GST in four groups were investigated by using northern blot analysis. The results showed that CYP1A1 gene expression was detected in all BaP-exposed groups and increased by longer exposure. The higher level of GST gene expression was detected in 12 and 24 hr groups comparing non-exposed and 6 hr exposed groups.