Abstract

Post-weaning diarrhea caused by enterotoxigenicEscherichia coliF18 (E. coliF18) causes significant economic losses for pig producers. Fucosyltransferase 8 (FUT8) is a glycosyltransferase that catalyzes core fucosylation; however, its role in mediating the resistance toE. coliF18 infection in pigs remains unknown. In this study, we systematically verified the relationship betweenFUT8expression andE. coliresistance. The results showed thatFUT8was expressed in all detected tissues of Meishan piglets and that its expression was significantly increased in the duodenum and jejunum ofE. coliF18-sensitive individuals when compared toE. coliF18-resistant individuals.FUT8expression increased after exposure toE. coliF18 (p< 0.05) and decreased significantly after LPS induction for 6 h (p< 0.01). Then, the IPEC-J2 stable cell line withFUT8interference was constructed, andFUT8knockdown decreased the adhesion ofE. coliF18ac to IPEC-J2 cells (p< 0.05). Moreover, we performed a comparative transcriptome study of IPEC-J2 cells afterFUT8knockdown via RNA-seq. In addition, further expression verification demonstrated the significant effect ofFUT8on the glycosphingolipid biosynthesis and Toll-like signaling pathways. Moreover, the core promoter ofFUT8, which was located at −1213 bp to −673 bp, was identified via luciferase assay. Interestingly, we found a 1 bp C base insertion mutation at the −774 bp region, which could clearly inhibit the transcriptional binding activity ofC/EBPαto anFUT8promoter. Therefore, it is speculated thatFUT8acts in a critical role in the process ofE. coliinfection; furthermore, the low expression ofFUT8is conducive to the enhancement ofE. coliresistance in piglets. Our findings revealed the mechanism of pigFUT8in regulatingE. coliresistance, which provided a theoretical basis for the screening ofE. coliresistance in Chinese local pig breeds.Keywords:pig;FUT8;E. coliF18;SNP;transcription factor