Neurexin and Neuroligin-based adhesion complexes drive axonal arborisation growth independent of synaptic activity
- King's College London, United Kingdom
- Harvard Medical School, United States
- Berlin Institute of Health, Germany
- National University of Singapore, Singapore
Abstract
Building arborisations of the right size and shape is fundamental for neural network function. Live imaging in vertebrate brains strongly suggests that nascent synapses are critical for branch growth during development. The molecular mechanisms underlying this are largely unknown. Here we present a novel system in Drosophila for studying the development of complex arborisations live, in vivo during metamorphosis. In growing arborisations we see branch dynamics and localisations of presynaptic proteins very similar to the 'synaptotropic growth' described in fish/frogs. These accumulations of presynaptic proteins do not appear to be presynaptic release sites and are not paired with neurotransmitter receptors. Knockdowns of either evoked or spontaneous neurotransmission do not impact arbor growth. Instead, we find that axonal branch growth is regulated by dynamic, focal localisations of Neurexin and Neuroligin. These adhesion complexes provide stability for filopodia by a 'stick-and-grow' based mechanism wholly independent of synaptic activity.
Article and author information
Author details
Funding
Biotechnology and Biological Sciences Research Council (BB/L022672/1)
- William D Constance
- Amrita Mukherjee
- Yvette E Fisher
- Sinziana Pop
- Eric Blanc
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: August 31, 2017
- Accepted: March 4, 2018
- Accepted Manuscript published: March 5, 2018 (version 1)
- Version of Record published: March 26, 2018 (version 2)
Copyright
© 2018, Constance 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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Neurexin and Neuroligin-based adhesion complexes drive axonal arborisation growth independent of synaptic activity
eLife 7:e31659.
https://doi.org/10.7554/eLife.31659
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