College of Animal Science and Technology, Yangzhou University, Yangzhou, China.
Joint International Research Laboratory of Agriculture and Agri-Product Safety, Yangzhou University, Yangzhou, China.
Front Immunol. 2022 May 25;13:881289. doi: 10.3389/fimmu.2022.881289. eCollection 2022.
Porcine epidemic diarrhea virus (PEDV) is an emerging coronavirus which causes acute diarrhea and destroys gastrointestinal barrier function in neonatal pigs. Trefoil factor 1 (TFF1) is a protective peptide for maintaining the integrity of gastrointestinal mucosa and reducing intestinal inflammation. However, its role in protecting intestinal epithelium against PEDV infection is still unclear. In this study, we discovered that TFF1 expression was activated in the jejunum of pigs with PEDV infection and TFF1 is required for the growth of porcine intestinal epithelial cells. For instance, inhibited cell proliferation and cell arrest were observed when is genetically knocked-out using CRISPR-Cas9. Additionally, depletion increased viral copy number and PEDV titer, along with the elevated genes involved in antiviral and inflammatory cytokines. The decreased mRNA expression is in line with hypermethylation on the gene promoter. Notably, the strong interactions of protein-DNA complexes containing CCAAT motif significantly increased C/EBPα accessibility, whereas hypermethylation of mC-6 loci decreased C/EBPα binding occupancies in promoter. Overall, our findings show that PEDV triggers the C/EBPα-mediated epigenetic regulation of in intestine epithelium and facilitates host resistance to PEDV and other infections.
猪流行性腹泻病毒(PEDV)是一种新兴的冠状病毒,可导致仔猪急性腹泻,并破坏胃肠道屏障功能。三叶因子 1(TFF1)是一种保护肽,可维持胃肠道黏膜的完整性并减轻肠道炎症。然而,其在保护肠上皮细胞免受 PEDV 感染方面的作用尚不清楚。在本研究中,我们发现 TFF1 表达在感染 PEDV 的仔猪空肠中被激活,并且 TFF1 是猪肠上皮细胞生长所必需的。例如,使用 CRISPR-Cas9 进行基因敲除时,观察到细胞增殖和细胞停滞受到抑制。此外, 耗竭增加了病毒拷贝数和 PEDV 滴度,同时上调了抗病毒和炎症细胞因子的基因。 基因启动子上的高甲基化导致 的 mRNA 表达下调。值得注意的是,含有 CCAAT 基序的蛋白-DNA 复合物的强相互作用显著增加了 C/EBPα 的可及性,而 mC-6 位点的高甲基化降低了 C/EBPα 在 启动子上的结合占有率。总体而言,我们的研究结果表明,PEDV 触发了肠上皮细胞中 C/EBPα 介导的 表观遗传调控,从而促进了宿主对 PEDV 和其他 感染的抵抗。