2010. University of Rennes 1, France. PhD
Drosophila visual system has proved useful model to study how neuronal diversity is generated and to explore the wiring of neuronal cells. In 1989, Fischbach and Dittrich described the morphology and projection of a large number of neuron cell types within the fly adult visual system. The medulla, which is the most complex ganglion, connects with the other neuropils lobula and lobula plate through transmedullary (Tm and TmY) neurons. Distal medulla (Dm) neurons and medulla intrinsic (Mi) neurons connect different layers of the medulla, and C neuron axons project into the medulla and the lamina. Although a huge variety of specialized neurons innervate the optic lobe, they all terminate in the appropriate neuropil layer, following a consistent neuronal topology, a process called retinotopy. However, the molecular cues involved in the proper targeting to their final site remain unknown.
My project focuses on a particular cell type connecting the medulla, the lobula and the lobula plate. While very few is known about this cell type, they interestingly present a similar morphology to another cell type connecting the medulla to the lobula, and for which some neurons have been described to be involved in motion vision. My goal is to characterize in details this neuron cell type and to determine the genetic program underlying their pathfinding from early development, as well as their function.