Abstract
A common feature of the brain is the arrangement of synapses in layers. To examine the significance of this organizational feature, we studied the functional development of direction-selective (DS) circuits in the tectum of astray mutant zebrafish in which lamination of retinal ganglion cell (RGC) axons is lost. We show that although never laminar, the tuning of DS-RGC axons targeting the mutant tectum is normal. Analysis of mutant tectal neurons at late developmental stages reveals that directional tuning is indistinguishable from wild-type larvae. Furthermore, we show that structural plasticity of tectal dendrites and RGC axons compensates for the loss of lamination, establishing connectivity between DS-RGCs and their normal tectal targets. However, tectal direction selectivity is severely perturbed at earlier developmental stages. Thus, the formation of synaptic laminae is ultimately dispensable for the correct wiring of direction-selective tectal circuits, but it is crucial for the rapid assembly of these networks.
Original language | English |
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Pages (from-to) | 999-1013 |
Number of pages | 15 |
Journal | Neuron |
Volume | 88 |
Issue number | 5 |
Early online date | 19 Nov 2015 |
DOIs | |
Publication status | Published - 2 Dec 2015 |
Bibliographical note
Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.Keywords
- Animals
- Animals, Genetically Modified
- Electroporation
- Gene Expression Regulation, Developmental/genetics
- Larva
- Mutation/genetics
- Nerve Net/physiology
- Orientation/physiology
- Receptors, Immunologic/genetics
- Retina/cytology
- Retinal Ganglion Cells/metabolism
- Superior Colliculi/cytology
- Visual Pathways/physiology
- Zebrafish
- Zebrafish Proteins/genetics