title: Identification of a potent antidiuretic factor acting on beetle Malpighian tubules.
abstract: Beetles, like other insects, depend on diuretic and antidiuretic hormones to control water balance. We have isolated, using head extracts from the beetle Tenebrio molitor, a peptide that strongly inhibits fluid secretion by the Malpighian tubules of this insect. This antidiuretic factor (ADF) appears to elicit its effect via cGMP as a second messenger but does not stimulate NO production. It has primary structure: Val-Val-Asn-Thr-Pro-Gly-His-Ala-Val-Ser-Tyr-His-Val-Tyr-OH. The ADF inhibits tubule secretion with high potency: the EC(50) is around 10 fM. It bears no significant resemblance to other biologically active neuropeptides. To our knowledge this is the only endogenous insect ADF acting on Malpighian tubules to be sequenced, and the first coleopteran (beetle) antidiuretic factor fully characterized to date.
authors.affiliation: Department of Biochemistry, University of Nevada, Reno, NV 89557-0014, USA.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Eigenheer
authors.forename: Susan W
authors.initials: SW
authors.lastname: Nicolson
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Schegg
authors.forename: J Joe
authors.initials: JJ
authors.lastname: Hull
authors.forename: David A
authors.initials: DA
authors.lastname: Schooley
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001681:Biological Assay; D003346:Corticotropin-Releasing Hormone / Q000737:chemistry* / Q000494:pharmacology; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism; D004231:Diuresis; D004305:Dose-Response Relationship, Drug; D004331:Drosophila melanogaster; D007301:Insect Hormones / Q000737:chemistry* / Q000494:pharmacology*; D008317:Malpighian Tubules / Q000187:drug effects*; D008969:Molecular Sequence Data; D009474:Neurons / Q000378:metabolism; D009569:Nitric Oxide / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000494:pharmacology; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D010455:Peptides / Q000737:chemistry; D011485:Protein Binding; D017386:Sequence Homology, Amino Acid; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013712:Tenebrio / Q000378:metabolism; D013997:Time Factors
chemical_list: D007301:Insect Hormones; D020030:Nitric Oxide Donors; D010455:Peptides; C097336:diuretic hormone, mealworm; D009569:Nitric Oxide; D003346:Corticotropin-Releasing Hormone; D000242:Cyclic AMP; D019001:Nitric Oxide Synthase; D006152:Cyclic GMP