Applications of high-throughput sequencing to symbiotic nematodes of the genus <Emphasis Type="Italic">Heterorhabditis</Emphasis>

Entomopathogenic nematodes of the genus Heterorhabditis live in symbiosis with pathogenic Photorhabdus bacteria. Heterorhabditis nematodes are entirely dependent on these bacteria for their food source; in return, the nematodes offer the bacteria a way to infect and kill insects. For their part, Photorhabdus bacteria are lethal to a broad range of insect hosts, to other nematodes, and to other microorganisms, but not to their Heterorhabditis hosts. These nematodes offer the potential to provide a robust experimental system for the in•depth study of a mutually beneficial symbiotic relationship, with both members of the partnership accessible to molecular and genetic studies. New genomic technologies offer the possibility for this potential to be realized, and for Heterorhabditis nematodes to become a standard model system for the investigation of host•symbiote relationships. We present a perspective on the application of these technologies to nematode•bacterial symbiosis and an update on our efforts to sequence three Heterorhabditis species reported at the recent NemaSym meeting.