1. INSECT HORMONES

2. Manduca sexta Rhodnius prolixus

3. Main Endocrine Centres Prothoracic (ecdysial) gland Neurosecretory cells in VNC Corpus allatum Corpus cardiacum Neurosecretory cells in SEG Neurosecretory cells in brain Brain Ovary

4. Corpora cardiaca Corpora allata

8. Neuroendocrine Regulation Central nervous system Neurohemal organ Neurosecretory cells Neurohormone Hormone Endocrine gland Target cell +/- Target cell

9. Physiological Actions of Hormones 1. Metabolism and homeostasis * Metabolism of carbohydrates, lipids * Water balance and diuresis (excretion of water following a blood meal) * Cardioactive and muscle stimulation/inhibition 2. Growth, molting and metamorphosis 3. Reproduction 4. Diapause = state of arrested development * Any stage - egg, larval, pupal, adult 5. Phase or caste polymorphism * Social insects - ants, termites, honeybees * Locusts and aphids show phase polymorphism 6. Behaviour * During molting process * Migration * Reproductive behavior * Social behavior * Pheromones

10. Sensitive periods for JH JH level Ecdysone level 4th instar5th instar

11. Outer epicuticle Inner epicuticle Epicuticle Exocuticle Endocuticle Epidermis Basement membrane Pore canals Procuticle Moulting and Hormones

12. Moulting Cycle (Part 1) Step 1Step 2Step 3/4

13. Moulting Cycle (Part 2) Step 5-7EcdysisNew Integument

14. CH 2 CH 3 CH 2 O O O C C C H H H C C CH 3 CH 2 CH 3 CH 2 O O O C C C H H H C C CH 3 CH 2 CH 3 CH 2 O O O C C C H H H C C Ecdysone Juvenile hormone I Juvenile hormone II Juvenile hormone III 20-Hydroxyecdysone

15. Juvenile hormone Penultimate larval instarFinal larval instarAdult JH sensitive period JH Titer

16. Corpus cardiacum Corpus allatum Brain (neurosecretory cells) Production, storage and release of protothoracicotropic hormone (PTTH} PTTH stimulates Ecdysone (ec) Juvenile hormone (JH) Binding protein (JHBP) JH-JHBP20-hydroxyecdysone chromosomes RNA Protein synthesis Larval structures chromosomes RNA Protein synthesis Pupal structures chromosomes RNA Protein synthesis Adult structures Action pathway for JH and Ecdysone

17. Moulting video http://www.vanderbilt.edu/exploration/news/news_bursicon.htm