Résumé
Hundreds of plant viruses are transmitted by aphid vectors, among which non-circulative ones areacquired and inoculated from one host to another within seconds. These viruses are retained onreceptors located at the surface of the cuticle of insect mouthparts. Members of the family Potyviridaeare the most abundant RNA viruses infecting plants, and they cause significant economic losses.Because of their importance, they are widely studied. However, their receptors in aphid stylets are stillpoorly characterized. Identification of these molecules remains a major challenge for understanding thetransmission mechanisms and would pave the way for alternative control strategies as potential targetsto prevent vector-borne transmission. Using the Turnip mosaic virus (TuMV, potyvirus) as a model, wedeveloped several approaches to characterize potyvirus-vector interactions. Using immunolocalizationand transmission electron microscopy studies, we mapped the retention sites of TuMV at the apical partof aphid stylets in the vicinity of the acrostyle, a cuticular organ known to host and expose receptors onthe stylet surface. In addition, peptide array assay revealed an interaction between the viral ligand ofTuMV, the helper component proteinase (HC-pro), and cuticular peptides present at the stylet surface.We further characterize the role of cuticular proteins of the acrostyle in TuMV transmission, using RNAinterference (RNAi) to reduce gene expression or aphid mutants generated via CRISPR-Cas9 technology.Altogether, our results lead to the identification of receptor candidates for TuMV.