Stereotyped terminal axon branching of leg motor neurons mediated by IgSF proteins DIP-α and Dpr10
Abstract
For animals to perform coordinated movements requires the precise organization of neural circuits controlling motor function. Motor neurons (MNs), key components of these circuits, project their axons from the central nervous system and form precise terminal branching patterns at specific muscles. Focusing on the Drosophila leg neuromuscular system we show that the stereotyped terminal branching of a subset of MNs is mediated by interacting transmembrane Ig superfamily proteins DIP-α and Dpr10, present in MNs and target muscles, respectively. The DIP-α/Dpr10 interaction is needed only after MN axons reach the vicinity of their muscle targets. Live imaging suggests that precise terminal branching patterns are gradually established by DIP-α/Dpr10-dependent interactions between fine axon filopodia and developing muscles. Further, different leg MNs depend on the DIP-α and Dpr10 interaction to varying degrees that correlate with the morphological complexity of the MNs and their muscle targets.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files
Article and author information
Author details
Funding
National Institutes of Health (R01NS070644)
- Richard S Mann
National Institutes of Health (U19NS104655)
- Richard S Mann
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- K VijayRaghavan, National Centre for Biological Sciences, Tata Institute of Fundamental Research, India
Version history
- Received: October 9, 2018
- Accepted: January 31, 2019
- Accepted Manuscript published: February 4, 2019 (version 1)
- Version of Record published: February 26, 2019 (version 2)
Copyright
© 2019, Venkatasubramanian et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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