Abstract
The binding affinity of insect molting hormone agonists, N-tert-butyl-N,N′-diacylhydrazine (DAH) analogs, against the molting hormone receptor proteins (EcR/USP) was measured. For the lepidopteran Chilo suppressalis, the receptor-binding activity of DAH analogs correlated linearly with their molting hormonal activity (in vitro) and insecticidal activity (in vivo). The binding activity of DAH analogs of C. suppressalis EcR/USP was higher than that of the dipteran Drosophila melanogaster EcR/USP. The binding activity of EcR/USP changed little when USP was exchanged between C. suppressalis and D. melanogaster. These results suggest that the selective toxicity of DAH analogs toward Lepidoptera is caused by the difference in the structure of EcR, not by that of USP. © Pesticide Science Society of Japan
