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Abstract
Neurons have highly asymmetric cellular morphologies and polarized cellular functions that are necessary for establishing neural circuitry and for proper functioning of the nervous system. Specialized processes, called dendrites, are used by neurons for reception of stimuli, while axons function in the transmission of signals. In neurons, mRNA localization and translational repression are used to change the protein composition of various regions of the cell, allowing for distinct axonal and dendritic morphologies and environments that are equipped for their various cellular tasks. A significant portion of the eukaryotic genome encodes for RNA-binding proteins (RBPs), which play important roles in localizing and translationally regulating RNAs. Since studies have shown that a large number of mRNAs are localized within dendrites, this suggests that the RBPs contribute broadly to neuronal development and function by localizing and regulating mRNAs. Based on a previous screen of RBP-encoding genes that affect dendrite morphogenesis in dendritic arborization neurons (da neurons) in Drosophila that identified 89 genes (Olesnicky, Killian, and Gavis; in preparation), I extended this screen to determine if any of these evolutionarily conserved RBP genes are important for dendrite morphogenesis in C. elegans PVD neurons as well. A significant decrease in dendritic arborization was found in dcr-1 mutants and preliminary results suggest that sup-26 and mtr-4 mutants may have decreased 3rd and 4th order dendritic branching. In addition, several other candidate genes are currently being investigated. Thus far, the results suggest that DCR-1/Dicer, an RBP involved in the microRNA pathway, SUP-26/Alan Shepard, an RBP implicated in translational control of mRNAs, and MTR-4/L(2)35Df, a component of the eukaryotic RNA exosome play an evolutionarily conserved role in dendrite development in flies and worms.