Juvenile hormone

Juvenile hormones (JHs) are a group of acyclic sesquiterpenoids that regulate many aspects of insect physiology. The first discovery of a JH was by Vincent Wigglesworth. JHs regulate development, reproduction, diapause, and polyphenisms.[1][2][3]

In insects, JH (formerly neotenin) refers to a group of hormones, which ensure growth of the larva, while preventing metamorphosis. Because of their rigid exoskeleton, insects grow in their development by successively shedding their exoskeleton (a process known as molting).

Juvenile hormones are secreted by a pair of endocrine glands behind the brain called the corpora allata. JHs are also important for the production of eggs in female insects.

JH was isolated in 1965 by Karel Sláma and Carroll Williams and the first molecular structure of a JH was solved in 1967.[4]

Most insect species contain only juvenile growth hormone (JH) III.[5] To date JH 0, JH I, and JH II have been identified only in the Lepidoptera (butterflies and moths). The form JHB3 (JH III bisepoxide) appears to be the most important JH in the Diptera, or flies.[6] Certain species of crustaceans have been shown to produce and secrete methyl farnesoate, which is juvenile hormone III lacking the epoxide group.[7] Methyl farnesoate is believed to play a role similar to that of JH in crustaceans.

Being a sesquiterpenoid, JH chemical structure differs significantly from the structure of other animal hormones. Some JH analogs have been found in conifers.[8]

  1. ^ Riddiford, L. M. (1994). "Cellular and molecular actions of juvenile hormone I. General considerations and premetamorphic actions". Advances in Insect Physiology. 24: 213–274. doi:10.1016/S0065-2806(08)60084-3. ISBN 9780120242245.
  2. ^ Watt, G. R.; Davey, K. G. (1996). "Cellular and Molecular Actions of Juvenile Hormone. II. Roles of Juvenile Hormone in Adult Insects". Advances in Insect Physiology. 26: 1–155. doi:10.1016/S0065-2806(08)60030-2. ISBN 9780120242269.
  3. ^ Nijhout, H. F. (1994). Insect Hormones. Princeton: Princeton University Press.
  4. ^ Röller, H.; Dahm, K.H.; Sweeley, C.C.; Trost, B.M. (1967). "The Structure of the Juvenile Hormone". Angewandte Chemie International Edition. 6 (2): 179–180. doi:10.1002/anie.196701792.
  5. ^ Judy, K.J.; Schooley, D.A.; Dunham, L.L.; Hall, M.S.; Bergot, B.J.; Siddall, J.B. (1973). "Isolation, Structure, and Absolute Configuration of a New Natural Insect Juvenile Hormone from Manduca sexta". Proceedings of the National Academy of Sciences of the United States of America. 70 (5): 1509–1513. Bibcode:1973PNAS...70.1509J. doi:10.1073/pnas.70.5.1509. PMC 433531. PMID 16592086.
  6. ^ Richard, D.S.; Applebaum, S.W.; Sliter, T.J.; Baker, F.C.; Schooley, D.A.; Reuter, C.C.; Henrich, V.C.; Gilbert, L.I. (1989). "Juvenile Hormone Bisepoxide Biosynthesis in vitro by the Ring Gland of Drosophila melanogaster: A putative juvenile Hormone in the higher Diptera". Proceedings of the National Academy of Sciences of the United States of America. 86 (4): 1421–1425. Bibcode:1989PNAS...86.1421R. doi:10.1073/pnas.86.4.1421. PMC 286704. PMID 2493154.
  7. ^ Laufer, H.; Borst, D.; Baker, F.C.; Carasco, C.; Sinkus, M.; Reuter, C.C.; Tsai, L.W.; Schooley, D.A. (1987). "Identification of a juvenile hormone-like compound in a crustacean". Science. 235 (4785): 202–205. Bibcode:1987Sci...235..202L. doi:10.1126/science.235.4785.202. PMID 17778635. S2CID 39560487.
  8. ^ Rogers, I. H.; J. F. Manville; T. Sahota (April 1974). "Juvenile Hormone Analogs in Conifers. II. Isolation, Identification, and Biological Activity of cis-4-[1′(R)-5′-Dimethyl-3′-oxohexyl]-cyclohexane-1-carboxylic Acid and (+)-4(R)-[1′(R)-5′-Dimethyl-3′-oxohexyl]-1-cyclohexene-1-carboxylic Acid from Douglas-fir Wood". Canadian Journal of Chemistry. 52 (7): 1192–1199. doi:10.1139/v74-187.