Résumé
Non-circulative stylet-borne viruses are primarily transmitted by aphids. The acrostyle, a specialized cuticular structure located at the tip of their maxillary stylets, plays a key role in the retention and transmission of such viruses, including the Cauliflower mosaic virus (CaMV). The acrostyle is lined with cuticular proteins, known as stylins, which feature exposed domains at the virus-vector interface. Beyond virus retention, the acrostyle also interacts with aphid salivary effectors, emphasizing its multifunctional role in both feeding behavior and virus transmission. Among stylins, Stylin-01 was previously identified as a receptor candidate for CaMV through various approaches. To confirm its function, we used CRISPR-Cas9 knockout aphid lines in which stylin-01 gene was completely disrupted. Here, we will present the characterization of the phenotypes of these mutants. Our results showed that the absence of Stylin-01 prevents CaMV retention and transmission, definitely demonstrating Stylin-01 as the main receptor for CaMV. Interestingly, our results also suggest a partial functional compensation by another stylin, which was overexpressed in the KO mutant line. Building on these findings, we expanded our investigation to receptors of potyviruses, a group of aphid transmitted viruses of agronomic importance. We used Turnip mosaic virus (TuMV) as a model in our study. We are currently exploring the role of stylins in TuMV transmission. The latest findings will be presented and discussed.