Document Type
Article
Publication Date
November 2003
Abstract
The organisational principles of locomotor networks are less well understood than those of many sensory systems, where in-growing axon terminals form a central map of peripheral characteristics. Using the neuromuscular system of the Drosophila embryo as a model and retrograde tracing and genetic methods, we have uncovered principles underlying the organisation of the motor system. We find that dendritic arbors of motor neurons, rather than their cell bodies, are partitioned into domains to form a myotopic map, which represents centrally the distribution of body wall muscles peripherally. While muscles are segmental, the myotopic map is parasegmental in organisation. It forms by an active process of dendritic growth independent of the presence of target muscles, proper differentiation of glial cells, or (in its initial partitioning) competitive interactions between adjacent dendritic domains. The arrangement of motor neuron dendrites into a myotopic map represents a first layer of organisation in the motor system. This is likely to be mirrored, at least in part, by endings of higher-order neurons from central pattern-generating circuits, which converge onto the motor neuron dendrites. These findings will greatly simplify the task of understanding how a locomotor system is assembled. Our results suggest that the cues that organise the myotopic map may be laid down early in development as the embryo subdivides into parasegmental units.
Recommended Citation
Landgraf, Matthias; Jeffrey, Victoria; Fujioka, Miki; Jaynes, James B.; and Bate, Michael, "Embryonic Origins of a Motor System: Motor Dendrites Form a Myotopic Map in Drosophila" (2003). Department of Biochemistry and Molecular Biology Faculty Papers. Paper 5.
https://jdc.jefferson.edu/bmpfp/5
Comments
This article was peer reviewed. It was published in PLoS Biology 1(2): e41, November 17, 2003, at http://biology.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pbio.0000041
Copyright: ©2003 Landgraf et al. This is an open-access article distributed under the terms of the Public Library of Science Open-Access License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.