Endogenous RNA viruses of plants in insect genomes

Endogenous viral elements (EVEs) derived from RNA viruses with no DNA stage are rare, especially those where the parental viruses possess single-strand positive-sense (ssRNA +) genomes. Here we provide evidence that EVEs that share a sequence similarity to ssRNA + viruses of plants are integrated into the genomes of a number of insects, including mosquito, fruit flies, bees, ant, silkworm, pea aphid, Monarch butterfly, and wasps. A preliminary phylogenetic analysis places these EVEs as divergent relatives of the Virgaviridae and three currently unclassified plant viral species. (C) 2012 Elsevier Inc. All rights reserved.