Identification of regulatory factors involved in the singular expression of members of an olfactory receptor gene cluster

The precise transcriptional specification of neuronal fate is central to the

development and function of nervous systems. In most olfactory systems, sensory

neurons are distinguished according to the odours they detect by exclusive

expression of a single olfactory receptor out of a vast repertoire. The olfactory system

of Drosophila is a powerful model to address how the precise transcription of one

receptor is established in different neuron populations, as it has significantly fewer

receptors and neurons, and greater genetic accessibility than that of mammals. This

project will investigate transcriptional regulation of the IR75 subfamily, which

comprises three tandemly-arranged receptor genes expressed in distinct populations

of sensory neurons in the antenna. First, I will generate a candidate list of

transcription factors (TFs) involved in IR75 subfamily receptor expression by

identifying TFs from the literature, motif searches and yeast one-hybrid screens.

Second, I will determine which TFs are required for expression of IR75 subfamily

members through an RNAi screen. Finally, I will investigate temporal, spatial and

biochemical function of positive hits from this screen to determine their precise

mechanism of action. Together, this work will provide insight into how tandemly gene

duplicates acquire unique expression patterns and how neurons acquire functional

diversity.