Correlation between the methylation of the FUT1 promoter region and FUT1 expression in the duodenum of piglets from newborn to weaning.

Alpha-(1,2)-fucosyltransferase (FUT1) gene has some influence on economically important traits and disease resistance. DNA methylation plays an important role in human diseases but is relatively poorly studied in pigs by regulating the mRNA expression of genes. The aim of this study was to analyze the influence of promoter methylation on the expression of FUT1 gene. We used bisulfite sequencing PCR (BSP) and qPCR to analyze the methylation of the FUT1 5'-flanking region and FUT1 mRNA expression in the duodenum of Sutai piglets from newborn to weaning. FUT1 contains three CpG islands upstream of the start codon, of which two are located in the putative promoter region containing multiple promoter elements and transcription factor binding sites, such as CpG islands, a CAAT box, SP1, and EARLY-SEQ 1. The CpG island between nucleotides -1762 and -580 had a low degree of methylation, and its methylation level was significantly lower in 35-day-old piglets than 8- and 18-day-old piglets (P < 0.05). FUT1 mRNA expression was significantly higher in 35-day-old piglets than 8- and 18-day-old piglets (P < 0.05). Pearson's correlation analysis showed that the methylation of the CpG island between nucleotides -1762 and -580 of FUT1 was significantly, negatively correlated with FUT1 mRNA expression (P < 0.05). These results demonstrate that differential methylation of CpG islands negatively regulates the expression of FUT1 in the porcine duodenum, suggesting a probable influence on the resistance of piglets to infection with ETEC F18.