Regulatory Effect of Methylation of the Porcine Gene Promoter Region on Its Expression Level and Porcine Epidemic Diarrhea Virus Resistance.

As an important carrier for intestinal secretion and water absorption, aquaporin 3 (AQP3) is closely related to diarrhea. In this study, we investigated the mechanisms of gene expression regulation in porcine epidemic diarrhea virus (PEDV)-induced diarrhea confirmed by PCR amplification and sequencing. Evaluation of intestinal pathology showed that diarrhea caused by PEDV infection destroyed the intestinal barrier of piglets. qPCR analysis showed that expression in the small intestine of PEDV-infected piglets was extremely significantly decreased. qPCR and Bisulfite sequencing PCR revealed an increase in the methylation levels of both CpG islands in the promoter region in the jejunum of PEDV-infected piglets. The methylation of mC-20 and mC-10 sites within the two CpG islands showed a significant negative correlation with expression. Chromatin Co-Immunoprecipitation (ChIP)-PCR showed that the Sp1 transcription factor was bound to the promoter region containing these two CpG sites. expression was also extremely significantly reduced in Sp1-inhibited IPEC-J2 cells, indicating that abnormal methylation at the mC-20 site of CpG1 and the mC-10 site of CpG2 reduces its expression in PEDV-infected piglet jejunum by inhibiting the binding of Sp1 to the promoter. These findings provide a theoretical basis for further functional studies of porcine .