New England Biolabs New England Biolabs Characterization of Ecdysone Receptor Target Genes in a Filarial Parasite, Dirofilaria immitis. New England Biolabs 32 Tozer Rd. Filarial parasites are responsible for several serious human diseases with symptoms such as lymphoedema, elephantiasis, or blindness. A useful model system for the study of these parasitic nematodes is Dirofilaria immitis, the causative agent of dog heartworm disease. D. immitis undergoes four molts from the microfilarial to the adult stage.
Many insects undergo a similar series of molts during their development.
In D. immitis, molting from the third to the fourth larval stage can be induced in vitro by ecdysone, suggesting that ecdysone may play a similar role in the development of D. immitis. Recent work in D. immitis has identified homologs of the EcR and usp genes, which comprise the functional ecdysone receptor in Drosophila. The ecdysone signal in Drosophila is modulated by a number of transcription factors that are induced as a primary response to ecdysone. Since EcR and usp homologs are found in D. immitis, it is possible that homologs of ecdysone receptor target genes also play a developmental role in D. immitis. I am searching for homologs of these target genes in D. immitis as well as undertaking an unbiased search for target genes of the D. immitis ecdysone receptor using a modified version of the yeast two-hybrid system.