Molecular cloning and expression analysis of Epinephelus coioides TAK1 after Cryptocaryon irritans infection

摘要: Cryptocaryon irritans a holotrichous ciliate is a marine fishe parasite, which can infect almost all kinds of marine fishe species and cause significant economic losses. Transforming growth factor-βactivated kinase-1 (TAK1), a serine/threonine kinase in themitogen-activated protein kinase kinase kinase (MAPKKK) family, plays an important role in thecascades of cellular responses aroused by changes in the environment. However, whether TAK1participate in fish defense against C. irritans is poorly understood. In this study, we cloned thecDNA sequences of EcTAK1, and found that the full length of cDNA sequences was 3568 bp, including a 5’-untranslated region (UTR) of 272 bp, a 3’-UTR of 1568 bp and an open readingframe (ORF) of 1728 bp which encods 575 amino acids. In expression analysis, the highestexpression of EcTAK1 was observed in the blood, followed by the brain and the gill, and theexpression of EcTAK1 did not differ significantly in other tissues. After infection with C. irritans, we found that EcTAK1 expression was down-regulated in the skin at 6 h, 1d and 3d; up-regulatedin the head kidney at 1d and reached its peak, while the expression was significantlydown-regulated at 3d and 5d. In the spleen, EcTAK1 expression was up-regulated at 6 h andreached its highest expression at 1d; and in the gill, it is evidently deduced at 6h and get to thehighest expression level at day 2 but was not significantly different from that of the uninfectedcontrol group. In conclusion, the EcTAK1 expression can be regulated at different degree indifferent tissues after C. irritans infection, indicating that TAK1 is connected to the immuneresponse of …