Bioactive peptides in invertebrate model organisms
Liliane Schoofs, Inge Mertens, Geert Baggerman, Peter Verleyen & Elke Clynen
Genome sequence projects in combination with advances in mass spectrometry and bioinformatics have created several new possibilities for comparative endocrinology. In 2001 we introduced the peptidomics technology that allows the identification of the complement of native (neuro)peptides in cells, tissues, organs and organisms. Especially when genome sequence information is available (D. melanogaster, A. mellifera, C. elegans…), neuropeptidomes were successfully identified and compared in different physiological conditions.
Synthetic libraries of newly sequenced peptides can be used to screen orphan neuropeptide G-protein coupled receptors in cell-based assays that express the receptor. This has boosted receptor identification in insects and other invertebrates. One of the advantages of model organisms, such as C. elegans and Drosophila is their amenability for genetic manipulations and the availability of knockouts as a result of (ongoing) gene disruption programs.
In this presentation, we show how all these technological developments contributed to the discovery of novel neuropeptide signalling systems in Drosophila and in C. elegans. In the nematode worm, we will focus on the functional characterisation of neuropeptide processing enzymes and two neuropeptide GPCR signalling systems, respectively related to the mammalian GnRH receptor and the VPAC receptor in vertebrates. We will discus the implications of these findings with respect to the evolutionary conservation of these signalling systems.