IP Endocrinology

Strategies for finding novel insect neurohormone receptors and their ligands, using the potentials of the Berkeley "Drosophila Genome Project"

C. Lenz, T. Secher &
C. J. P. Grimmelikhuijzen

Dept. of Cell Biology, Zoological Institute, University of Copenhagen, Universitetsparken 15, DK-2100 Copenhagen, Denmark

We developed a method for creating “electronic probes” to screen the Berkeley “Drosophila Genome Project” database for G protein-coupled (presumably neurohormone) receptors. Using these “electronic probes”, we could localize DNA sequences in the Drosophila database that coded for two different Drosophila G protein-coupled receptors that were clearly related to the mammalian galanin receptors. Using PCR, with Drosophila cDNA as a template, and oligonucleotide probes coding for the exons of the presumed Drosophila receptor genes, we were able to clone the cDNA’s for these receptors: Drosophila galanin receptor-1 (DGR-1) has 37% amino acid sequence identity with the rat galanin receptor type-1. The DGR-1 gene contains ten introns and eleven exons and is located at the distal end of the X chromosome. During the preparation of our manuscript on this work [1], a competing research group published a Drosophila cDNA sequence that was nearly identical to our DGR-1 cDNA [2]. This group also reported that their cDNA coded for a receptor for a Drosophila allatostatin, which is a neuropeptide that inhibits the release of juvenile hormone from the corpora allata, but that also has other inhibitory actions [2]. The other receptor gene that we cloned with our approach, DGR-2, codes for a receptor that is very closely related to DGR-1 (85% amino acid sequence identity) and, thus, very likely represents a second receptor for Drosophila allatostatin. Furthermore, by classical homology screening using PCR, we also cloned a presumed allatostatin receptor from the silkworm Bombyx mori.

[1] Lenz, C., Søndergaard, L., and Grimmelikhuijzen, C. J. P. (2000) Biochem. Biophys. Res. Commun., March 1 issue, in press.
[2] Birgül, N., Weise, C., Kreienkamp, H.-J., and Richter, D. (1999) EMBO J. 18: 5892-5900.

Index terms: Drosophila melanogaster, Bombyx mori, allatostatin, juvenile hormone, development, reproduction.

Copyright: The copyrights of this document belong to the authors (see right-most box in title table) This abstract 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.