Biomaterial Database

Juvenile hormone inhibits ecdysone secretion and responsiveness to prothoracicotropic hormone in prothoracic glands of Bombyx mori. 1989

S Sakurai, and M Okuda, and T Ohtaki

Department of Biology, Faculty of Science, Kanazawa University, Japan.

The role of juvenile hormone (JH) in the regulation of prothoracic gland activity was investigated during the early days of the last (fifth) larval instar of Bombyx mori. Allatectomy on the day of larval ecdysis into the fifth instar or 1 day before ecdysis shortened the time between larval ecdysis and gut purge. Prothoracic glands of the freshly ecdysed fifth instar larvae were inactive and did not respond to the prothoracicotropic hormone (PTTH), whereas those larvae that were allatectomized 1 day before ecdysis exhibited secretory activity in vitro and were capable of responding to PTTH. When corpora allata were removed from freshly ecdysed fifth instar larvae, the prothoracic glands became competent to respond to PTTH in 6 hr and exhibited secretory activity in vitro 9 hr after the allatectomy. Treatment of allatectomized larvae with a JH analog resulted in the recovery of the normal inactive state of the glands. These data suggest that JH acts during the early stages of the instar to suppress both the secretory activity of prothoracic glands and also the acquisition of competence to respond to PTTH.

UI	MeSH Term	Description	Entries
D007301	Insect Hormones	Hormones secreted by insects. They influence their growth and development. Also synthetic substances that act like insect hormones.	Insect Hormone,Hormone, Insect,Hormones, Insect
D007605	Juvenile Hormones	Compounds, either natural or synthetic, which block development of the growing insect.	Insect Growth Regulator,Insect Growth Regulators,Juvenile Hormone,Growth Regulators, Insect,Regulators, Insect Growth,Growth Regulator, Insect,Hormone, Juvenile,Hormones, Juvenile,Regulator, Insect Growth
D007814	Larva	Wormlike or grublike stage, following the egg in the life cycle of insects, worms, and other metamorphosing animals.	Maggots,Tadpoles,Larvae,Maggot,Tadpole
D008845	Microinjections	The injection of very small amounts of fluid, often with the aid of a microscope and microsyringes.	Microinjection
D001921	Brain	The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.	Encephalon
D004441	Ecdysterone	A steroid hormone that regulates the processes of MOLTING or ecdysis in insects. Ecdysterone is the 20-hydroxylated ECDYSONE.	20-Hydroxyecdysone,Beta-Ecdysone,Crustecdysone,20 Hydroxyecdysone,Beta Ecdysone
D004702	Endocrine Glands	Ductless glands that secrete HORMONES directly into the BLOOD CIRCULATION. These hormones influence the METABOLISM and other functions of cells in the body.	Endocrine Gland,Gland, Endocrine
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012831	Bombyx	A genus of silkworm MOTHS in the family Bombycidae of the order LEPIDOPTERA. The family contains a single species, Bombyx mori from the Greek for silkworm + mulberry tree (on which it feeds). A native of Asia, it is sometimes reared in this country. It has long been raised for its SILK and after centuries of domestication it probably does not exist in nature. It is used extensively in experimental GENETICS. (From Borror et al., An Introduction to the Study of Insects, 4th ed, p519)	Bombyx mori,Silkmoths,Silkworms,Silkmoth,Silkworm,Bombyx morus,Bombyxs,mori, Bombyx
D013909	Thorax	The upper part of the trunk between the NECK and the ABDOMEN. It contains the chief organs of the circulatory and respiratory systems. (From Stedman, 25th ed)	Chest,Thoraces,Chests,Thorace