Abstract

Calcium (Ca) is a messenger that regulates a multitude of physiological processes, but its functions in antiviral progress remain undefined. In this study, we found that Ca 2+ enhances fish survival to defend against spring viraemia of carp virus (SVCV) infection by reversing the instability of p53 mediated by the viral protein. First, Ca 2+ significantly protected cells and fish against SVCV infection by inducing early apoptosis. Additionally, p53 expression, which was inhibited by SVCV N protein, was upregulated by Ca 2+ treatment. Then, the mechanism underlying the reduction of K63-linked p53 ubiquitination by SVCV N protein via the K358 site was completely prevented by Ca 2+ . These findings reveal the role of Ca 2+ in lower vertebrates in the antiviral response, which is connected to and corresponds with viral immune evasion, providing a solution to fish diseases caused by pathogens.