Molecular characterization and function of EGFR during viral infectionprocess in Mandarin fishSiniperca chuatsi.

Epidermal growth factor receptor (EGFR) is a tyrosine kinase protein and plays a critical role in virus infection by modulating innate immunity. In this study, we cloned and sequenced the EGFR coding sequence of mandarin fish, designed as scEGFR, and explored its characteristics. scEGFR mRNA was widely expressed in the tested tissues of mandarin fish, and the higher mRNA levels were expressed in kidney and spleen. scEGFR expression was up-regulated in spleen and CPB cells at early stage of ISKNV and SCRV infection. Gefitinib (EGFR inhibitor) inhibited ISKNV and SCRV replication, and increased the expression of the interferon-stimulated genes (ISG). However the EGF (EGFR activator) promoted ISKNV and SCRV replication, and decreased the interferon-stimulated genes. Those results indicated that scEGFR and its signaling involved in ISKNV and SCRV infection, and EGFR activation negatively regulated the interferon response, providing a potential target for the development of new therapic strategy against ISKNV and SCRV.