Golden pompano, Trachinotus ovatus, is a perciform fish with great economic value and is widely cultured in the coastal areas of China. The wide occurrence of bacterial, parasitic and viral diseases has seriously threatened the sustainable development of the golden pompano culture industry. Janus kinases (JAKs) play important roles in most cytokine-mediated inflammatory responses, antiviral immune responses, autoimmune responses and disease pathologies. The present study aimed to obtain the full-length cDNA sequences of JAKs (JAK1, JAK2a, JAK3 and TYK2) from golden pompano and investigate their roles following stimulation with lipopolysaccharide (LPS), polyriboinosinic-polyribocytidylic acid (poly I:C) and Vibrio alginolyticus using RT-PCR, RACE-PCR and real-time qPCR methods. All four JAK proteins of golden pompano shared similar conserved domains, had high identities and clustered well with their teleost counterparts in phylogenetic analysis. Furthermore, these four genes were expressed in all examined tissues from healthy fish and induced in head kidney (HK), spleen, liver and gill post LPS, poly I:C and V. alginolyticus stimulation. Knowledge of the roles of JAKs in the immune response to different microbial pathogens provides a basis for further understanding of these functions.

Transforming growth factor-β (TGF-β)-activated kinase 1 (TAK1), TAK1-binding protein 1 (TAB1) and TAB2 are components of the mitogen-activated protein kinase (MAPK) pathway. In this study, TAK1, TAB1 and TAB2 were characterized from golden pompano (Trachinotus ovatus), a marine fish of great economic value, and named as trTAK1, trTAB1 and trTAB2, respectively. The lengths of the cDNA sequences of the three genes were 2429 bp, 2068 bp and 4229 bp and encoded 575, 506 and 759 amino acids, respectively. The trTAK1, trTAB1 and trTAB2 genes shared high sequence identities and were well clustered with their counterparts from other fish species. Real-time qPCR analysis showed that the three genes were constitutively expressed in all the selected tissues of healthy pompano, and the expression levels of the three genes were significantly up-regulated in head kidney and spleen following Vibrio alginolyticus, lipolysaccharide (LPS) and polyinosinic polycytidylic acid (poly I:C) challenge, indicating their roles in the immune response against pathogens in golden pompano. Our results provide a basis for further study of the functions of these genes in golden pompano.