Juvenile hormone is required to couple imaginal disc formation with nutrition in insects

Faculty of Agriculture and Life Sciences, Hirosaki University, Khirosaki, Aomori, Japan
Science (Impact Factor: 31.48). 07/2006; 312(5778):1385-8. DOI: 10.1126/science.1123652
Source: PubMed

ABSTRACT In starved larvae of the tobacco hornworm moth Manduca sexta, larval and imaginal tissues stop growing, the former because they lack nutrient-dependent signals but the latter because of suppression by juvenile hormone. Without juvenile hormone, imaginal discs form and grow despite severe starvation. This hormone inhibits the intrinsic signaling needed for disc morphogenesis and does so independently of ecdysteroid action. Starvation and juvenile hormone treatments allowed the separation of intrinsic and nutrient-dependent aspects of disc growth and showed that both aspects must occur during the early phases of disc morphogenesis to ensure normal growth leading to typical-sized adults.

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