Fig. 9: Proposed model of RDV hijacking NcVg for transmission.

NcVg of nonviruliferous leafhoppers associates with NcRab5 via interaction, facilitating their release together from salivary glands to cavities and finally entering rice phloem when leafhoppers feed. The released NcVg in rice phloem induces the expression and activity of OsGSTF12, which catalyzes GSH-dependent oxidation, ultimately scavenging excessive H₂O₂ and benefiting leafhopper feeding. The RDV infection in salivary glands indirectly induces NcVg accumulation mediated by RDV-upregulated NcRab5, resulting in the formation of RDV-NcVg-NcRab5 complexes. The induced complexes are packaged into RDV-induced exosomes and then released into cavities, eventually entering rice phloem. The upregulated NcVg in rice phloem enhances the GSH-dependent oxidation catalysis and H₂O₂ scavenging, finally facilitating leafhoppers feeding and viral transmission.