Abstract: Signal transduction and transcriptional activation factor 6 plays an important role in the inflammation induced by IL-4 and IL-13. A full-length cDNA of the stat6 in sea perch (Lateolabrax japonicus) was amplified by RT-PCR and SMART RACE methods. The cDNA was 3938 bp with 5′-UTR of 295 bp, 3′-UTR of 1369 bp and open reading frame of 2274 bp. It encoded a protein of 757 amino acids with the molecular weight of 86.43 ku and pI 5.90. The blast analysis indicated that the deduced amino acids sequence of sea perch STAT6 shared the highest identity of 93.7% with Siniperca chuatsi and the lowest identity of 41.7% with homo sapien. Real-time PCR results showed that stat6 was expressed in all tissues tested with higher levels in spleen, kidney, brain，intestine and gill. The expression of stat6 increased obviously in spleen, kidney, intestine and gill after intraperitoneal injectin of Vibrio harveyi. This obtained information will provide a theoretical basis for studying the molecular mechanism of fish stat6 in regulating fish immune response to pathogens.

Key words: stat6, Lateolabrax japonicus, cloning, tissue expression