IP Nervous

Molecular characterization of the allatostatin peptide family

W. G. Bendena 1 & S. S. Tobe 2

1 Dept. of Biology, Queen's University, Kingston, ON, Canada K7L 3N6, Email: ; 2)Dept. of Zoology, University of Toronto, Toronto ON, Canada M5S 1A1

Juvenile hormone (JH) plays a central role in the metamorphosis and reproduction of most insect species. The biosynthesis of JH within the corpora allata of insects can either be stimulated or inhibited by the neuropeptides allatotropin and allatostatin(AST), respectively. The allatostatin precursor from 6 cockroach species has been cloned and characterized. Each precursor contains either 13 or 14 related peptides that represent an intraphylectic family of peptides whose C-termini contain the sequence Tyr/PheXaaPheGlyLeu/Ile-NH2. Analysis of AST sequences suggest that the AST sequences were generated through a process of internal gene duplication which occurred before these species diverged from each other in evolutionary time. The AST peptide family also appears to function as potent inhibitors of muscle contraction and are synthesized in, and potentially secreted from a population of granulated hemocytes suggesting additional functions. The diversity of action of this peptide family suggests that multiple receptors may exist for ASTs. Approaches to identifying these receptors will be presented.

Index terms: Diploptera punctata, neuropeptide, receptors.

Copyright: The copyrights of this abstract belong to the author (see right-most box of title table). This document also appears in Session 13 – INSECT PHISIOLOGY, NEUROSCIENCES, IMMUNITY AND CELL BIOLOGY Symposium and Poster Session, ABSTRACT BOOK II – XXI-International Congress of Entomology, Brazil, August 20-26, 2000.