Fig. 7.

The schematic diagram indicating toll-dorsal pathway mediated homeostasis for the persistent transmission of RSV in L. striatellus. The Toll pathway is activated by the interaction between the Toll receptor of L. striatellus and RSV NP. Then, Dorsal participated in the antiviral defense of L. striatellus by regulating the target gene LsZN708 and induced the downstream immune response pathways (such as autophagy) against RSV infection (Left). Conversely, RSV also developed antidefense strategy by using its NS4 protein to antagonize the host Toll antiviral defense through competitively binding to LsDorsal with LsMSK2 kinase, resulting in the inhibition of LsDorsal phosphorylation and translocation to the nucleus (Right).