Abstract：
Vibrio parahaemolyticus causes diseases in aquatic organisms, leading to substantial financial losses to the aquaculture industry; its flagellin F (flaF) protein triggers severe inflammation in host cells. To enhance the understanding of the function of flaF in V. parahaemolyticus infection, in this study, a flaF-deficient mutant was constructed by employing two-step homologous recombination. The flaF-deficient mutant induced a significantly lower toll-like receptor 5 (TLR5) expression and apoptosis in fish intestinal epithelial cells than the wild-type V. parahaemolyticus. Furthermore, fluorescence labelling and microscopy analysis of TLR5 showed that V. parahaemolyticus and its mutant strain significantly enhanced TLR5 expression. Additionally, the findings suggest that flaF deletion did not significantly affect the expression of myeloid differentiation factor 88 (MyD88) and interleukin-8 (IL-8) induced by V.parahaemolyticus. In summary, V. parahaemolyticus induced a TLR5-dependent inflammatory response and apoptosis through MyD88, which was observed to be influenced by flaF deletion. In this study, we obtained stable mutants of V. parahaemolyticus via target gene deletion-which is a rapid and effective approach-and compared the induction of inflammatory response and apoptosis by V. parahaemolyticus and its mutant strain, providing novel perspectives for functional gene research in V. parahaemolyticus.
摘要：
副溶血性弧菌在水生生物中引起疾病，导致水产养殖业的重大经济损失;其鞭毛蛋白F（flaF）蛋白引发宿主细胞严重炎症。提高对副溶血性弧菌感染中flaF功能的认识,在这项研究中，通过采用两步同源重组构建flaF缺陷型突变体。与野生型副溶血性弧菌相比，flaF缺陷型突变体在鱼肠上皮细胞中诱导的toll样受体5（TLR5）表达和凋亡显着降低。此外，TLR5的荧光标记和显微镜分析显示副溶血弧菌及其突变株显著增强了TLR5的表达。此外,研究结果表明，flaF缺失对副溶血性弧菌诱导的骨髓分化因子88（MyD88）和白细胞介素8（IL-8）的表达没有显着影响。总之,副溶血弧菌通过MyD88诱导TLR5依赖性炎症反应和细胞凋亡,观察到其受到flaF缺失的影响。在这项研究中,我们通过靶基因缺失获得了稳定的副溶血弧菌突变体，这是一种快速有效的方法，并比较了副溶血弧菌及其突变株对炎症反应和细胞凋亡的诱导，为副溶血性弧菌功能基因研究提供新的视角。
