Isolation of Juvenile Hormone Epoxide Hydrolase Genes in the Malpighian Tubules of the Tobacco Hornworm, Manduca Sexta

Abstract

Understanding the regulation of Juvenile Hormone (JH) titer in insects is critical for understanding the biochemical processes related to metamorphosis. The cDNAs from several potential isoforms of the enzyme Juvenile Hormone Epoxide Hydrolase have been isolated from the Malpighian tubules of Manduca sexta. Modified PCR methods are being used to search for any other potential isoforms of this enzyme that may be contained in a Malpighian tubule expressed sequence tag library. To date, this protocol has yielded three potential genes, in addition to the two originally isolated. Future research will allow the creation of baculovirus vectors containing the isolated potential JHEH genes and the identified isoforms will be expressed in an insect cell culture. The isoforms will be assayed for activity in metabolizing the three forms of JH present in M. sexta through the use of radiolabeled JH’s.