We are studying the molecular genetic basis of olfaction, using Drosophila melanogaster as a model organism. This research topic is of broad significance from both fundamental and applied perspectives as the sense of smell is vital for most animals in finding food, identifying mates, and avoiding predators.
It is also a fascinating sense for neurobiologists, as animals can detect and discriminate amongst literally thousands of different chemical compounds. How can this be achieved at the molecular level? How does such a complex information coding system work?
As well as this fundamental interest, there are also applied aspects to this research in pest control and in the development of biosensors, machines that can sense volatile chemicals in the environment. In insects odorants are initially detected by a family of odorant receptor proteins, however the signal transduction pathway(s) activated by these receptor proteins are not well understood.
We are identifying genes involved in this pathway in Drosophila, which offers many advantages such as a sequenced genome and powerful genetic approaches to study gene function.
MACPF – (Membrane Attack Complex/Perforin-like)
(In collaboration with Professor James Whisstock, Department of Biochemistry & Molecular Biology)
The Drosophila torso-like gene is the only fly member of the Membrane Attack Complex / Perforin-like (MACPF) protein superfamily, which include pore forming toxins that play key roles in vertebrate immunity, often by forming pores in membranes and lysing cells. However some MACPF proteins, such as Tsl, play a role outside immunity and intriguingly appear to be essential for developmental processes.
Tsl is maternally expressed and secreted by a subpopulation of follicle cells at the anterior and posterior regions of the maturing oocyte, where it is proposed it functions to permit proteolytic cleavage of the ligand for the Torso receptor tyrosine kinase, ensuring Torso signalling only in these regions and, in consequence, the development of appropriate anterior and posterior structures.
However, the mechanism of action of Tsl in this process is not known. Tsl also has other roles in Drosophila, as our studies have shown that it is zygotically expressed in a complex and dynamic pattern during embryonic development, including in a subset of the central nervous system.