Mitogen-activated protein kinase 4 (MKK4), a member of the MAP kinase family, play important roles in response to many environmental and cellular stresses in mammals. In this study, three MKK4 subtypes, EcMKK4-1, EcMKK4-2 and EcMKK4-3, were obtained from grouper Epinephelus coioides. The open reading frame (ORF) of EcMKK4s are obtained and the EcMKK4s proteins contain highly conserved domains: a S_TKc domain, a canonical diphosphorylation group and two conserved MKKK ATP binding motifs, Asp-Phe-Gly (DFG) and Ala-Pro-Glu (APE). EcMKK4s could be found both in the cytoplasmic and nuclear. The EcMKK4s mRNA were detected in all E. coioides tissues examined with the different expression levels, and the expression were up-regulated during SGIV (Singapore grouper iridescent virus) or Vibrio alginolyticus infection. EcMKK4 could significantly reduce the activation of AP-1 reporter gene. The results suggested that EcMKK4s might play important roles in pathogen-caused inflammation.

丝裂原活化蛋白激酶 4 (MKK4) 是 MAP 激酶家族的成员，在哺乳动物对许多环境和细胞应激的反应中发挥着重要作用。在这项研究中，从石斑鱼Epinephelus coioides中获得了三种 MKK4 亚型 EcMKK4-1、EcMKK4-2 和 EcMKK4-3 。获得了 EcMKK4s 的开放阅读框 (ORF)，并且 EcMKK4s 蛋白包含高度保守的结构域：一个 S_TKc 结构域、一个典型的二磷酸化基团和两个保守的 MKKK ATP 结合基序，Asp-Phe-Gly (DFG) 和 Ala-Pro-Glu （猿）。EcMKK4s 可以在细胞质和细胞核中找到。EcMKK4s mRNA 在所有E. coioides组织中检测到不同的表达水平，并且在 SGIV（新加坡石斑鱼虹彩病毒）或溶藻弧菌感染。EcMKK4可以显着降低AP-1报告基因的激活。结果表明，EcMKK4s 可能在病原体引起的炎症中发挥重要作用。