Molecular phylogenetics and the classification of honey bee viruses.

We present the phylogenetic relationships of several picorna-like RNA viruses found in honey bees, with respect to 13 additional plant and animal positive-strand RNA viruses. Most of the honey bee viruses fall into an unnamed family of insect RNA viruses typified by the Drosophila C virus. Different bee viruses are broadly distributed within this group, suggesting either that the ability to infect honey bees has evolved multiple times, or that these viruses are generalistic in their abilities to infect insect hosts. At least one major change in gene order has occurred among the bee viruses, based on their phylogenetic affiliations. At the amino-acid level, the bee viruses differed by 15-28% at three conserved loci. Most differed by greater than 50% at the RNA level, indicating that sequence-based methods for bee virus identification must be tailored to at least three different virus clades independently.