鲈鱼stat6 cDNA克隆及表达分析

Gene cDNA cloning and expression analysis of stat6 from Lateolabrax japonicas

信号转导和转录激活因子6(Signal transducers and activators of transcription,STAT6)在白介素IL-4、IL-13诱导的炎症反应中起关键作用。利用RT-PCR和SMART RACE的方法从鲈鱼(Lateolabrax japonicus)肝脏中克隆得到stat6全长cDNA序列。该序列的c DNA为3938 bp,5'非翻译区295 bp,3'非翻译区1369 bp,开放阅读框2274 bp,可编码757个氨基酸,蛋白质分子质量为86.43 ku,等电点为5.90。分析STAT6氨基酸序列发现,与鳜鱼相似性达93.7%;与人相似性为41.7%。荧光定量PCR结果表明,stat6在脾、头肾、大脑、肠和鳃中表达较高。腹腔注射哈维氏弧菌3 h后,stat6在脾、头肾、肠、鳃组织中的表达均显著上调(P<0.05),表明细菌感染会增加stat6的表达。研究结果为进一步研究鱼类stat6在病原菌感染免疫中的分子机制提供一定基础。

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 c DNA 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 p I 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. Realtime 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.