VIRTUAL SPEAKER - Decoding Mite-Mediated Transmission of Kitaviruses and Dichorhaviruses

Kitavirids and dichorhaviruses form a heterogeneous group of plant-infecting viruses mainly characterized by causing non-systemic infections under natural conditions. Some of these viruses are causal agents of serious diseases that affect crops of economic value, including citrus, coffee, and orchids. Members of the family Kitaviridae [ss(+)RNA] are assigned to three genera. While cileviruses and higreviruses are transmitted by mites of the genus Brevipalpus, blunerviruses are vectored by eriophyid mites. Dichorhaviruses [ss(-)RNA, fam. Rhabdoviridae], meanwhile, are also transmitted by Brevipalpus mites and have a propagative virus-vector relationship that impacts the mite's development and life span. Studies of the citrus leprosis cilevirus C (CiLV-C) - B. yothersi vector interaction have demonstrated a propagative relationship with no apparent implications for mite biology. At the molecular level, the overall response of B. yothersi to cilevirus and dichorhavirus, including the regulation of genes associated with detoxification and immunity, was similar. However, some marker genes associated with UPR/ER stress pathways showed contrasting transcriptional regulation during the mites´ interaction with CiLV-C or coffee ringspot dichorhavirus. Protein-protein analyses, i.e., BiFC, Y2H, and CoIP, have disclosed Brevipalpus mite factors involved in its interaction with cilevirus and dichorhavirus. Collectively, our findings open a new avenue for developing novel mite – and virus - control strategies.