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Updated: Jul 14, 2026
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Visualization of Motor Axon Navigation and Quantification of Axon Arborization In Mouse Embryos Using Light Sheet Fluorescence Microscopy
Published on: May 11, 2018
Ena/VASP function in retinal axons is required for terminal arborization but not pathway navigation
Asha Dwivedy1, Frank B Gertler, Jeffrey Miller
1Department of Anatomy, University of Cambridge, Downing Street, Cambridge CB2 3DY, UK.
Development (Cambridge, England)
|May 18, 2007
Summary
Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) proteins are not essential for retinal axon pathfinding, even without filopodia. However, these proteins are crucial for growth cone branching in the optic tectum.
Area of Science:
- Neuroscience
- Cell Biology
- Developmental Biology
Background:
- The Enabled/vasodilator-stimulated phosphoprotein (Ena/VASP) protein family is vital for actin cytoskeleton remodeling and filopodia formation in growth cones.
- Previous studies suggested filopodia are necessary for growth cone navigation in the developing visual pathway.
Purpose of the Study:
- To investigate the role of Ena/VASP proteins and filopodia in growth cone navigation and terminal arborization in vivo.
- To determine if Ena/VASP proteins are essential for retinal axon pathfinding.
Main Methods:
- Targeted Ena/VASP proteins to mitochondria in Xenopus retinal ganglion cells (RGCs) using the EVH1 domain and FP4 ligand motif.
- Generated RGCs lacking functional Ena/VASP proteins and filopodia.
- Observed growth cone behavior and axon navigation in the developing visual pathway.
Main Results:
- RGCs with reduced Ena/VASP function exhibited lamellipodial growth cones lacking filopodia and showed slower advancement in the optic tract.
- Despite the absence of filopodia, axons successfully navigated the optic pathway without significant guidance errors.
- Depletion of Ena/VASP proteins severely impaired growth cone branching within the optic tectum.
Conclusions:
- Ena/VASP proteins and filopodia are non-essential for retinal axon pathfinding during development.
- The Ena/VASP protein family plays a critical role in the formation of terminal arborizations in the optic tectum.
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