Abstract
SummaryWhat developmental mechanisms underlie functional diversification of neural circuits? We address this question inDrosophilalarvae by focusing on segmentally homologous Wave command neurons, which diversify their wiring and function in a location-specific manner. Anterior Wave (a-Wave) neurons extend axons anteriorly and connect to circuits inducing backward locomotion, whereas posterior Wave (p-Wave) neurons extend axons posteriorly and trigger forward locomotion. Here, we show that Frizzled receptors DFz2 and DFz4, together with the DWnt4 ligand, regulate the segment-specific Wave axon projection.DFz2knock-down (KD) not only reroutes a-Wave axons to posterior neuromeres but also biases its motor command to induce forward instead of backward locomotion. Thus, segment-specific axon guidance diversifies the function of homologous command neurons in behavioral regulation. Since control of anterior-posterior (A-P) axon guidance by Wnt/Fz-signaling is evolutionarily conserved, our results reveal a potentially universal principle for formation and diversification of the command system in the nerve cord.
Publisher
Cold Spring Harbor Laboratory