Toll-like receptors (TLRs) and their associated signaling pathways play pivotal roles in the immune response to invading pathogens. Here, TLR13, TLR22, tumor necrosis factor receptor-associated factor 6 (TRAF6), and transforming growth factor-β-activated kinase1 (TAK1) were characterized in the soiny mullet (Liza haematocheila), representative mugilid species that is widely cultured in Asia. The four mullet genes, which shared characteristic features with their counterparts in other teleosts, were ubiquitously expressed in all of the examined tissues, albeit with different expression patterns. Following Streptococcus dysgalactiae infection, the four genes were upregulated to different degrees in various mullet tissues. These results indicated that the four genes were involved in the mullet immune response to bacterial infection. To the best of our knowledge, this is the first characterization of these four genes in mullet. Our results provide a basis for future studies of TLR signaling pathways in mullet, as well as for similar studies in other mugilids.

Toll 样受体 (TLR) 及其相关信号通路在对入侵病原体的免疫反应中起着关键作用。在这里，TLR13、TLR22、肿瘤坏死因子受体相关因子6（TRAF6）和转化生长因子-β-活化激酶1（TAK1）在亚洲广泛养殖的代表性鲻鱼（Liza haematocheila）中得到表征. 四种鲻鱼基因与其他硬骨鱼类中的对应物共享特征，在所有检查的组织中普遍表达，尽管表达模式不同。继停乳链球菌之后感染后，4个基因在各种鲻鱼组织中均有不同程度的上调。这些结果表明这四个基因参与了鲻鱼对细菌感染的免疫反应。据我们所知，这是对鲻鱼中这四个基因的首次表征。我们的结果为未来研究鲻鱼中的 TLR 信号通路以及其他鲻鱼的类似研究提供了基础。