Insulin/IGF signaling regulates the change in commitment in imaginal discs and primordia by overriding the effect of juvenile hormone.

摘要: At the beginning of final larval (fifth) instar Manduca sexta, imaginal precursors including wing discs and eye primordia initiate metamorphic changes, such as pupal commitment, patterning cell proliferation. Juvenile hormone (JH) prevents these changes in earlier instars starved larvae, but nutrient intake overcomes this effect JH latter. In study, we show that a molecular marker broad, is up-regulated by feeding on sucrose or bovine insulin bombyxin larvae. This could not be prevented JH. vitro had no broad expression relieved suppression was directly disc shown its reduction presence receptor dsRNA. penultimate fourth insulin. The became responsive to action during molt fifth together with ability become pupally committed response 20-hydroxyecdysone. Thus, acts metamorphosis-initiating factor precursors.