Résumé
Aphids are the only known vectors of stylet-borne non-circulative viruses comprising hundreds of species in the generaCaulimovirus, Potyvirus and Cucumovirus. These viruses can be acquired and inoculated from one plant to another withinseconds when aphids feed. They are retained on receptors located at the surface of the cuticle of insect mouthparts. TheCauliflower mosaic virus (CaMV) was shown to bind the acrostyle, an organ at the tip of aphid stylets. Stylin-01, acuticular protein from the CPR family directly accessible at the surface of the acrostyle, was shown to play a role in CaMVtransmission. To characterize Stylin-01 role in viruses transmission as a receptor for CaMV and other viruses, stable Stylin-01 mutant lines were generated via CRISPR-Cas9 technology in the pea aphid Acyrthosiphon pisum. Our work focuses ontwo Stylin-01 mutant lines: one with a complete knockout of the protein and another with an alteration at the cuticle/fluidprotein interface. While demonstrating a major role of Stylin-01 in CaMV transmission, our results show that at least asecond cuticular protein is involved in the retention of this virus at the surface of the acrostyle. In addition, our dataindicate that the transmission efficiency of Turnip mosaic virus (TuMV, Potyvirus) is poorly affected in aphid mutant lines,thus showing that Stylin-01 is not the main receptor for TuMV. All together, our data demonstrate the existence of at least two virus receptors in aphid stylets.