The miR-100-mediated pathway regulates apoptosis against virus infection in shrimp.

The process of programmed cell death process or apoptosis can be regulated by microRNAs, 21-25 nt short non-coding RNAs. However, a comprehensive view of apoptosis-associated miRNAs has not been intensively characterized. In this study, the shrimp miRNA microarray data showed that 199 miRNAs were involved in the regulation of apoptosis, among which 8 miRNAs were evolutionarily conserved in animals. The loss-of-function experiments in vivo in shrimp revealed that miR-100 was served as an anti-apoptosis miRNA through targeting the mRNA of trypsin gene. The results indicated that the silencing of miR-100 expression resulted in the increase of apoptotic activity of shrimp hemocytes and further led to the decreases of virus genome copies in shrimp and virus-infected shrimp mortality compared with the controls. The findings showed that miR-100-trypsin signaling pathway played an important role in the antiviral immunity by regulating apoptosis. Therefore, our study presented a novel miR-100-mediated pathway in the regulation of apoptosis.