Chemistry & Biochemistry
October 11, 2012
A. Joffre Mercier, Ph.D.
Professor, Department of Biology
Associate Dean (Graduate Studies & Research)
Faculty of Mathematics & Science
"Fruitflies: A Model System for Studying Neuromuscular Synapses"
Monday, Oct. 15, 2012
C640 - UHall
All are welcome to attend
The human brain contains over 50 oligopeptides that function as chemical transmitters, but details about their physiological functions are not completely understood. Much of the research in my lab is aimed at investigating the effects of neuropeptide hormones on chemical synapses and on behaviour, using invertebrates as model experimental systems. Fruitflies (Drosophila melanogaster) provide several advantages as an experimental system, including: (a) a relatively small number of neurons, (b) nerve cells and muscles that can be identified reliably from one specimen to the next, (c) a fully sequenced genome and (d) mutant and transgenic lines that can be utilized to examine mechanisms of neuropeptide action.
We have demonstrated that one Drosophila neuropeptide (DPKQDFMRFamide) acts both on the synaptic terminals of nerve cells, where it enhances release of chemical transmitters onto muscle cells, and on the muscle cells themselves, where it initiates contractions. By combining our physiological experiments with Drosophila mutants, transgenic lines and RNA interference, we have found that both of these effects are mediated by G-protein coupled receptors.