Recent work on a diverse array of echinoderm species has demonstrated, as is true in amphibians, that thyroid hormone (TH) accelerates development to metamorphosis. Interestingly, the feeding larvae of several species of sea urchins seem to obtain TH through their diet of planktonic algae (exogenous source), whereas nonfeeding larvae of the sand dollar Peronella japonica produce TH themselves (...

Exploring the possibility of enhancing the properties of baculoviruses as biological control agents of insect pests, we tested the effect of expressing an insect gene (jhe) encoding juvenile hormone esterase. Juvenile hormone esterase inactivates juvenile hormone, which regulates the outcome of an insect molt. A cDNA encoding the juvenile hormone esterase of Heliothis virescens was inserted int...

The juvenile hormones of insects regulate an unusually large diversity of processes during postembryonic development and adult reproduction. It is a long-standing puzzle in insect developmental biology and physiology how one hormone can have such diverse effects. The search for molecular mechanisms of juvenile hormone action has been guided by classical models for hormone-receptor interaction. ...

Topical application of juvenile hormone analog induces soldier development in the ant Pheidole bicarinata. Soldier induction takes place if the juvenile hormone analog is present during a period of sensitivity that occurs during the last larval instar. Control of worker dimorphism seems to be accomplished through control of timing of metamorphosis. The smallest size at which metamorphosis can b...

Secondary metabolites are known to serve a wide range of specialized functions including communication, developmental control and defense. Genome sequencing of several fungal model species revealed that the majority of predicted secondary metabolite related genes are silent in laboratory strains, indicating that fungal secondary metabolites remain an underexplored resource of bioactive molecule...

The caste-specific regulation of vitellogenin synthesis in the honeybee represents a problem with many yet unresolved details. We carried out experiments to determine when levels of vitellogenin are first detected in hemolymph of female castes of Apis mellifera, and whether juvenile hormone and ecdysteroids modulate this process. Vitellogenin levels were measured in hemolymph using immunologica...

BACKGROUND Predilection of juvenile angiofibromas in adolescent boys has prompted the hypothesis of hormone-dependent tumor growth. However, knowledge on expression and function of sex hormone receptors in juvenile angiofibromas is still sparse and inconsistent. METHODS Transcript and protein expression of sex hormone receptors in juvenile angiofibromas was studied by quantitative reverse tra...

We demonstrate links between the protein content of diets, food intake, the resultant body mass, juvenile hormone synthesis by the corpora allata, and o6cyte maturation in Blattella germanica. Oiicyte development and oviposition were suppressed in starved females as well as in females fed deficient artificial diets (lowor high-protein contetits). On all diets, as well as in starved females, oii...

Total extracts from worker larvae, pupae, and adults of the honey bee were analyzed for their juvenile hormone contents. Using the 10-(heptafluorobutyrate)-ll-methoxy derivative, the hormone was isolated in yields of 20 — 50% in nanogram quantities as calculated from isotope dilution and from gas chromatography with electron capture detection. The procedure is sensitive enough to isolate the ju...