EN
Neuropeptides synthesized by secretory neurons or interneurons in the CNS are important regulators of physiology, behaviour, and development. They are synthesized from larger precursor molecules by a specific set of enzymes. Combining the power of Drosophila neurogenetics with semiquantitative peptidomics, we are characterising the functional role of these processing enzymes. The results obtained so far are in line with genomic data suggesting that there typically is one major specific gene/enzyme for each processing step, which is in contrast to the situation in mammals. As expectable, many behavioural phenotypes in peptide processing mutants are reminiscent of known peptidergic phenotypes. Theoretically, processing enzymes represent an ideal cellular target to regulate divergent peptidergic signalling in the neuroendocrine and nervous system. The findings above make the fruitfly an ideal genetically and biochemically tractable model to test this hypothesis. Moreover, we will outline how these findings in concert with cell-specific genetic targeting could be used to identify new peptidergic phenotypes, as well as to analyse the function of “functionally redundant” peptides.