Cell fate decisions during development require robust mechanisms to ensure proper patterning of tissues. In many sensory circuits, such as the primate or the Drosophila visual system, neuronal fate specification relies on stochastic decisions. A neuron that relies on an initially stochastic decision must then stabilize its choice to maintain proper identity, and then to inform other cells of its choice. The latter is of high importance for neurons, as they need to connect to the proper targets to faithfully transmit neural information. In the Drosophila retina such stochastic mechanisms are employed to ensure the random distribution of photoreceptors with different spectral sensitivity.
Even as we begin to understand the genetic networks that control specification of PR subtypes in the retina, we do not yet know how this choice is coordinated with the type or fate of target neurons in the brain. My project is to understand how stochastically specified neurons in the Drosophila visual system target their proper partners to faithfully transmit visual information to the brain, and whether the fate of the targeted neuron is affected by stochastic choice of its partner in the retina.