| Title: | Injection of Dip-allatostatin or Dip-allatostatin pseudopeptides into mated female Diploptera punctata inhibits endogenous rates of JH biosynthesis and basal oocyte growth |
| Author(s): | Garside CS; Nachman RJ; Tobe SS; |
| Address: | "Department of Zoology, University of Toronto, M5S 3G5, Toronto, On, Canada" |
| DOI: | 10.1016/s0965-1748(00)00041-2 |
| ISSN/ISBN: | 0965-1748 (Print) 0965-1748 (Linking) |
| Abstract: | "Studies on the catabolism of allatostatins (ASTs) provided the rationale for the design of a series of Dip-allatostatin-derived pseudopeptide mimetic analogues. In vitro, the Dip-ASTs and pseudopeptides show varying degrees of resistance to catabolism and all show significant inhibition of juvenile hormone (JH) biosynthesis. This study was undertaken to determine whether potent Dip-ASTs and/or their pseudopeptide mimetic counterparts caused 'allatostatic' effects in vivo following injection into mated female Diploptera punctata. Animals injected with aqueous solvent or Dip-AST 7(1-7) N-terminal fragment, which excludes the active core region of the ASTs, were used as controls. An in vitro radiochemical assay revealed that injection of Dip-AST 5, 7 or pseudopeptide analogues 397-2 or AST(b)φ2 significantly inhibited the biosynthesis of JH (P<0.05). The results also indicate that basal oocyte growth was significantly inhibited by injection of these same compounds, with the exception of Dip-AST 7 (P<0.05). Analogues 396-1 and 419 did not significantly inhibit rates of JH biosynthesis but did significantly inhibit the growth of basal oocytes. Analyses of feeding, excretion and food absorption/utilization patterns of these same animals suggested that these compounds are not toxic to the insect; rather they directly inhibit the biosynthesis of JH by the corpora allata, and reduce the rate of growth of basal oocytes. Disruption of critical reproductive and/or developmental processes by pseudopeptide analogues of the ASTs could provide novel and selective strategies for future insect pest management" |
| Keywords: | "Animals Cockroaches Fat Body/metabolism Feeding Behavior Female Hormone Antagonists/*metabolism Juvenile Hormones/*biosynthesis Male Neuropeptides/*metabolism Oocytes/*growth & development/metabolism Sexual Behavior, Animal Solubility;" |
| Notes: | "MedlineGarside, C S Nachman, R J Tobe, S S eng Research Support, Non-U.S. Gov't England 2000/07/06 Insect Biochem Mol Biol. 2000 Aug-Sep; 30(8-9):703-10. doi: 10.1016/s0965-1748(00)00041-2" |
