AUTHOR=Xiao Yeyi , Zhou Yajing , Sun Shouyong , Wang Haifei , Wu Shenglong , Bao Wenbin 

TITLE=Effect of Promoter Methylation on the Expression of Porcine MUC2 Gene and Resistance to PEDV Infection

JOURNAL=Frontiers in Veterinary Science

VOLUME=8

YEAR=2021

URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2021.646408

DOI=10.3389/fvets.2021.646408

ISSN=2297-1769

ABSTRACT=<p>Integrity of the intestinal mucosal barrier is closely related to the occurrence of diarrhea. As an important component protein of the intestinal mucosal barrier, Mucin 2 (MUC2) plays a critical role in preventing the invasion of pathogens, toxins, and foreign bodies. In the present study, we preliminary verified the function of the porcine <italic>MUC2</italic> gene in resisting porcine epidemic diarrhea virus (PEDV) infection and investigated the effect of DNA methylation in the promoter region on <italic>MUC2</italic> gene expression. The results showed that after PEDV infection, the intestinal mucosal barrier was damaged. Moreover, <italic>MUC2</italic> expression was significantly higher in PEDV-infected piglets than in healthy piglets (<italic>P</italic> &lt; 0.01). The mRNA expression of <italic>MUC2</italic> was significantly higher in PEDV-infected IPEC-J2 cells than in non-infected IPEC-J2 cells (<italic>P</italic> &lt; 0.05). Methylation of the mC-5 site in the <italic>MUC2</italic> promoter inhibited the binding of Yin Yang 1 (YY1) to the promoter, down regulated the expression of <italic>MUC2</italic> and increased the susceptibility of piglets to PEDV. In conclusion, this study suggests that <italic>MUC2</italic> plays an essential regulatory role in PEDV infection. High <italic>MUC2</italic> expression improves the resistance of pigs to PEDV infection. The binding of YY1 to the <italic>MUC2</italic> promoter is hindered by the methylation of the mC-5 site, which downregulates <italic>MUC2</italic> expression and ultimately affects the resistance of pigs to PEDV infection.</p>