Analysis of the Role of KLF4 in the Regulation of Porcine Epidemic Diarrhea Virus Infection.

Porcine epidemic diarrhea virus (PEDV) is a primary pathogen responsible for viral diarrhea in swine. The identification of host resistance genes and key regulatory elements represents a critical prerequisite for developing novel control strategies. Krüppel-like factor 4 (KLF4), a multi-functional transcription factor, is known to regulate pathogenic infections; however, its specific roles in PEDV infection remain largely undefined. In this study, we found that KLF4 expression was upregulated following PEDV infection. Next, we constructed KLF4 knockout and overexpression cells and infected them with PEDV. The results show that viral RNA and protein expression levels and infectious viral titers were significantly enhanced in PEDV-infected KLF4 knockout cells compared to infected wild-type cells. In contrast, PEDV infection levels were significantly decreased in KLF4 overexpression cells relative to control cells. Transcriptomic analysis reveals that KLF4 significantly influences the expression of genes involved in key signaling pathways, including PI3K/Akt and MAPK. Overall, our findings elucidate the functional roles and underlying mechanisms of KLF4 during PEDV infection, offering valuable molecular targets for PEDV prevention and control.