C-type lectin binds envelope protein of white spot syndrome virus and induces antiviral peptides in red swamp crayfish

Previously a pattern recognition receptor (PRR) from kuruma shrimp was found able to recognize bacterial glycans by the C-type lectin domain (CTLD) and to interact with Jak/Stat receptor Domeless by the interleukin-like coiled coil (cc) region. In the current study, its homolog, namely Pc-ccCL, was found important in the antiviral response in red swamp crayfish Procambarus clarkii. This PRR plays a role by inhibiting white spot syndrome virus (WSSV) infection in a Jak/Stat dependent manner. The CTLD can bind the viral envelope protein VP28, while the cc region determines the dependence on Jak/Stat pathway. Two anti-lipopolysaccharides factors were identified as the downstream antiviral peptides. This study provides new insights into the antiviral signaling in invertebrates. Furthermore, the mechanism that a PRR recognizes virus and directly activates Jak/Stat pathway and antiviral-effector expression represents a simple but fast antiviral strategy in crustaceans.