Identification and cDNA cloning of novel juvenile hormone responsive genes from fat body of the bean bug, Riptortus clavatus by mRNA differential display.

Juvenile hormone (JH) induces termination of diapause and initiation of reproductive maturation in the adult female bean bug, Riportus clavatus. Applying PCR-based differential display, we have identified four novel JH-responsive cDNAS, that is, three repressible (JR-1, 2 and 3) and one inducible (JI-1). These DNA fragments were partially sequenced and compared with sequences in the data base. JR-3 was shown to have similarity to the transferrins of other insects, which have been reported as JH-suppressed genes. JI-1 has similarity to vitellogenin of Aedes aegypti. On the other hand, JR-1-1 and 2 have no significant similarity to other known sequences. For JR-1, the full cDNA sequence was determined: it contained 913 bp, encoding 194 amino acid residues with a calculated M.W. of 21,531 Da in the mature protein. A total of six JH-responsive genes or cDNAs (four suppressible and two inducible or stimulated), including the already isolated JH-responsive cyanoprotein genes (CP-alpha and beta), have been isolated and are available for further comparative analysis of gene structure and regulatory mechanisms in the same tissue under the same hormonal conditions.