CLL, together with C1qR, suppresses WSSV infection by regulating the activation of Dorsal

The body's recognition of pathogenic microorganisms plays an important role in host resistance to pathogen infection. Here, we identified a lectin, <i>Pc</i>CLL, in the red swamp crayfish <i>Procambarus clarkii</i>, which contains a C1q-like sequence and might be involved in antiviral immunity. C1qR located on the cell membrane can recognize white spot syndrome virus by interacting with VP28. Then, it recruits <i>Pc</i>CLL and promotes the nuclear translocation of Dorsal. This process cannot be achieved without SRPK, which is a splicing regulator that can phosphorylate proteins. CLL (C1q-like motif that is part of the globular head of C1q) and C1qR (gC1qR homolog) interact with each other, and they are involved in the antiviral immune response by activating Dorsal. This may be a new mechanism for the host to recognize pathogens.