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Juvenile hormone (JH) given at pupariation inhibits bristle formation and causes pupal cuticle formation in the abdomen of Drosophila melanogaster due to its prolongation of expression of the transcription factor Broad (BR). In a microarray analysis of JH-induced gene expression in abdominal integument, we found that Krüppel homolog 1 (Kr-h1) was(More)
Juvenile hormone controls the timing of insect metamorphosis. As a final step of juvenile hormone biosynthesis, juvenile hormone acid O-methyltransferase (JHAMT) transfers the methyl group from S-adenosyl-l-methionine to the carboxyl group of farnesoic acid and juvenile hormone acid. The developmental expression profiles of JHAMT mRNA in the silkworm Bombyx(More)
Juvenile hormone (JH) prevents ecdysone-induced metamorphosis in insects. However, our knowledge of the molecular mechanisms of JH action is still fragmented. Krüppel homolog 1 (Kr-h1) is a JH-inducible transcription factor in Drosophila melanogaster (Minakuchi, C., Zhou, X., Riddiford, L.M., 2008b. Krüppel homolog 1 (Kr-h1) mediates juvenile hormone action(More)
cDNA cloning of ecdysone receptor (EcR) and ultraspiracle (USP) of the coleopteran Colorado potato beetle Leptinotarsa decemlineata (LdEcR and LdUSP) was conducted. Amino-acid sequences of the proteins deduced from cDNA sequences showed striking homology to those of other insects, especially the coleopteran yellow mealworm Tenebrio molitor. Northern(More)
This study examined the acetylcholinesterase 1 gene (AChE1) in Plutella xylostella strains with different sensitivities to acephate. Multiple haplotypes of the gene were found in the field-collected strains including distinct haplotypes carrying one or both previously reported mutations (A298S and G324A). Moreover, sequencing results indicated the presence(More)
The Krüppel homolog 1 gene (Kr-h1) has been proposed to play a key role in the repression of insect metamorphosis. Kr-h1 is assumed to be induced by juvenile hormone (JH) via a JH receptor, methoprene-tolerant (Met), but the mechanism of induction is unclear. To elucidate the molecular mechanism of Kr-h1 induction, we first cloned cDNAs encoding Kr-h1(More)
In this study, we characterized prophenoloxidase (proPO, (PPO)) genes of Tribolium castaneum and examined their involvement in antimicrobial host defense. Amino acid sequence comparison with well-characterized PPO proteins from other insect species suggested that T. castaneum PPO genes encoded functional proenzymes, with crucial sequence motifs being(More)
Inhibition of the binding of [3H]ponasterone A ([3H]PoA) by ecdysone agonists including diacylhydrazines such as RH-5849, tebufenozide (RH-5992) and methoxyfenozide (RH-2485) was examined in intact Drosophila Kc cells. The reciprocal logarithm of the concentration at which there is 50% inhibition of [3H]PoA binding, pIC(50) (M), was determined as the(More)
In holometabolous insects, Krüppel homolog 1 (Kr-h1) and broad (br) are key players in the juvenile hormone (JH) regulation of metamorphosis: Kr-h1 is an early JH-response gene, while br is a transcription factor that directs pupal development. Thrips (Thysanoptera) are classified as hemimetabolous insects that develop directly from nymph to adult, but they(More)
Using Tribolium castaneum, we quantitatively investigated the induction of nine antimicrobial peptide (AMP) genes by live gram-negative bacteria (Escherichia coli and Enterobacter cloacae), gram-positive bacteria (Micrococcus luteus and Bacillus subtilis) and the budding yeast (Saccharomyces cerevisiae). Then, five representative AMP genes were selected,(More)