Juvenile hormone synthesis by corpora allata of tomato moth Lacanobia oleracea (Lepidoptera: Noctuidae), end the effects of allatostatins and allatotropin in vitro
Title:
Juvenile hormone synthesis by corpora allata of tomato moth Lacanobia oleracea (Lepidoptera: Noctuidae), end the effects of allatostatins and allatotropin in vitro
The nature and rate of juvenile hormone (JH) biosynthesis and effects of allatostatins and allatotropin have been investigated in isolated corpora allata (CA) of adults and larvae of the noctuid tomato moth, Lacanobia oleracea. In adult female CA, mean rates of synthesis were relatively constant (10-16 pmol/pr/h) at all times. However, the range of JH synthesis by individual CA of similarly aged insects was quite large (2-30 pmol/pr/h). High performance liquid chromatography (HPLC) separation shows that adult female moth CA synthesise predominantly JH I and JH II. Rates of JH synthesis in vitro are dependent on methionine concentration. Synthetic Manduca sexta allatostatin (Mas-AS) caused a dose-dependent inhibition of JH synthesis by adult female CA but only to a max. of 54%, whilst 10 µM synthetic M. sexta allatotropin caused a 37% stimulation of CA activity. At 1 mM the cockroach allatostatin, Dip-allatostatin-2, had no significant effect on JH synthesis. In larval L. oleracea, rates of JH biosynthesis were very low., Neil Audsley, Robert J. Weaver, John P. Edwards, and Lit