Glycogen synthase kinase-3 (GSK3), a cytoplasmic serine/threonine-protein kinase involved in a large number of key cellular processes, is a little-known signaling molecule in virus study. In this study, a GSK3 protein which was highly similar to GSK3β homologs from other species in Litopenaeus vannamei (designated as LvGSK3β) was obtained. LvGSK3β was expressed constitutively in the healthy L. vannamei, at the highest level in the intestine and the lowest level in the eyestalk. White spot syndrome virus (WSSV) reduced LvGSK3β expression was in immune tissues including the hemocyte, intestine, gill and hepatopancreas. The inhibition of LvGSK3β resulted in significantly higher survival rates of L. vannamei during WSSV infection than the control group, and significantly lower WSSV viral loads in LvGSK3β-inhibited L. vannamei were observed. Knockdown of LvGSK3β by RNAi resulted in increases in the expression of LvDorsal and several NF-κB driven antimicrobial peptide (AMP) genes (including ALF, PEN and crustin), but a decrease in LvCactus expression. Accordingly, overexpression of LvGSK3β could reduce the promoter activity of LvDorsal and several AMPs, while the promoter activity of LvCactus was increased. Electrophoretic mobility shift assays (EMSA) showed that LvDorsal could bind to the promoter of LvGSK3β. The interaction between LvGSK3β and LvDorsal or LvCactus was confirmed using co-immunoprecipitation (Co-IP) assays. In addition, the expression of LvGSK3β was dramatically reduced by knockdown of LvDorsal. In summary, the results presented in this study indicated that LvGSK3β had a negative effect on L. vannamei by mediating a feedback regulation of the NF-κB pathway when it is infected by WSSV.

糖原合酶激酶3（GSK3）是一种参与许多关键细胞过程的胞质丝氨酸/苏氨酸蛋白激酶，是病毒研究中鲜为人知的信号分子。在这项研究中，与来自其他物种的GSK3β同源物高度相似的GSK3蛋白凡纳滨对虾获得（称为LvGSK3β）。LvGSK3β在健康人群中组成性表达南美白对虾，在肠道中最高水平，在眼柄中最低。白斑综合症病毒（WSSV）降低了LvGSK3β在免疫组织中的表达，包括血细胞，肠，腮和肝胰腺。对LvGSK3β的抑制可显着提高LvGSK3β的生存率南美白对虾 在WSSV感染期间的感染率较对照组明显降低，并且LvGSK3β抑制的WSSV病毒载量显着降低 南美白对虾被观察。RNAi抑制LvGSK3β导致LvDorsal和一些NF-κB驱动的抗菌肽（AMP）基因（包括ALF，PEN和Crustin）的表达增加，但LvCactus表达减少。因此，LvGSK3β的过表达可降低LvDorsal和几种AMPs的启动子活性，而LvCactus的启动子活性增加。电泳迁移率变动分析（EMSA）显示LvDorsal可以与LvGSK3β的启动子结合。LvGSK3β与LvDorsal或LvCactus之间的相互作用已通过免疫共沉淀（Co-IP）分析得以证实。另外，LvDorsal的敲低显着降低了LvGSK3β的表达。总之，本研究结果表明LvGSK3β对南美白对虾 通过介导WSSV感染NF-κB途径的反馈调节。