Role of epithelial cells in detection and response to sensory stimuli in Drosophila

Abstract

Interactions between cell types plays an important role in shaping the morphology and function of those cells. One powerful example is in the peripheral nervous system, where sensory neurons coordinate with epidermal structures to help us sense the environment around us. However, there are many aspects of this sensory system that have only recently been investigated. First, this thesis reviews the current understanding of the mechanisms that guide, shape, and regulate the response to external stimuli in the epidermis. It describes our changing historical perspective on epithelial cells from simple physical support structures to active participants in the sensory apparatus. Second, we use the Drosophila peripheral nervous system as a model to identify novel regulators of neuron-epithelial interactions. We found that the microRNA miR-14 is required in the epithelium, where it likely regulates the expression of gap junctions, which ensure tight coupling between adjacent epithelial cells. This prevents precocious innervation of the neuron into the cell junction. Changes in dendrite morphology and innervation of the junction are highly correlated with changes in sensitivity of the nociceptive neuron.