Cloning and Sequence Analysis of the Alpha and Rho-Class GST Genes in Orange-Spotted Grouper (Epinephelus coioides)
斜带石斑鱼alpha型与rho型GST基因cDNA全序列的克隆与分析

To research the molecular mechanism of phase II detoxifizyme (glutathione S-transferases, GST) in the metabolism of toxics in marine fish, we cloned the full-length cDNA sequences of alpha-GST (GSTA) and rho-class GST (GSTR) genes from the liver of orange-spotted grouper (Epinephelus coioides) by RT-PCR and RACE methods. The sequence analysis showed that the complete GST cDNA sequence of GSTA of orange-spotted grouper was 1008bp in length, containing a coding region of 672bp (encoding 223 amino acids). And the complete cDNA sequence of GSTR was 1002bp in length, containing a coding region of 678bp (encoding 225 amino acids). Results of the phylogenetic analysis revealed that the deduced amino acid sequence of the orange-spotted grouper was very similar to the GSTA of other fishes, such as common carp and zebrafish. The GSTR existed only in fish, but not in any other aquatic animals or land mammals (e.g. rat, mouse and human).