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bioRxiv · 10.1101/027375

Glial and neuronal Semaphorin signaling instruct the development of a functional myotopic map for Drosophila walking

Durafshan Sakeena Syed·Swetha B.M.·O. Venkateswara Reddy·Heinrich Reichert·VijayRaghavan K.
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Abstract

Motoneurons developmentally acquire appropriate cellular architectures that ensure connections with postsynaptic muscles and presynaptic neurons. In Drosophila, leg motoneurons are organized as a myotopic map, where their dendritic domains represent the muscle field. Here we investigate mechanisms underlying development of aspects of this myotopic map, required for walking. A behavioral screen identified roles for Semaphorins (Serna) and Plexins (Plex) in walking behavior. Deciphering this phenotype, we show that PlexA/Sema1a mediates motoneuron axon branching in ways that differ in the proximal femur and distal tibia, based on motoneuronal birth order. Importantly, we show a novel role for glia in positioning dendrites of specific motoneurons; PlexB/Sema2a is required for dendritic positioning of late-born motoneurons but not early-born motoneurons. These findings indicate that communication within motoneurons and between glia and motoneurons, mediated by the combined action of different Plexin/Semaphorin signaling systems, are required for the formation of a functional myotopic map.

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Durafshan Sakeena Syed, Swetha B.M., O. Venkateswara Reddy, Heinrich Reichert, VijayRaghavan K.. 2015-09-22. Glial and neuronal Semaphorin signaling instruct the development of a functional myotopic map for Drosophila walking. https://doi.org/10.1101/027375

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