Endogenous viral elements in vector arthropod genomes

The documentation of endogenous viral elements (EVEs) - virus-derived genetic information integrated into the genomes of a host and its descendants - has offered new insights into how arthropods such as mosquitos and ticks respond to viral infection via RNA silencing pathways, and their capacity to spread and maintain vector-borne viruses in the environment. Recent advances in genome sequencing have resulted in a wealth of highly contiguous vector arthropod genomes, and with them, the ability to identify and assess the provenance and shared ancestry of EVE elements in multiple lineages. Our analysis uses informatic approaches to analyze the available sequenced genomes of thirty-one mosquito and nine tick species for EVEs, with special reference to Non-retroviral Integrated RNA Virus (or NIRV) elements. Results highlight multiple independent acquisitions and of similar EVEs among congeneric hosts as well as shared derived viral elements presumably acquired prior to the divergence of multiple genera. These results will inform current and future work regarding past associations with, and future vector potential of, arthropod vector species with regard to the viruses from which their “viral fossils” are derived.