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Updated: May 8, 2026
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Analyses of Actin Dynamics, Clutch Coupling and Traction Force for Growth Cone Advance
Published on: October 21, 2021
Integrins and cAMP mediate netrin-induced growth cone collapse
M L Lemons1, M L Abanto, N Dambrouskas
1Department of Natural Sciences, Assumption College, Worcester MA 01609, United States; Department of Neurobiology and Anatomy, University of Utah School of Medicine, 401 MREB, 20 North 1900 East, Salt Lake City, UT 84132, United States.
Brain Research
|September 5, 2013
Summary
Netrin-1 triggers growth cone collapse via integrin activation and increased cAMP, but only on specific substrates like laminin-1. This reveals a novel mechanism for axon guidance.
Area of Science:
- Neuroscience
- Cell Biology
- Developmental Biology
Background:
- Axon guidance relies on growth cones interpreting complex extracellular cues.
- Integrins are implicated in axon guidance through interactions with guidance molecules, but mechanisms remain unclear.
Purpose of the Study:
- To investigate the interaction between integrins and netrin-1 in growth cone collapse.
- To elucidate the role of integrins and cAMP in netrin-1-mediated growth cone guidance.
Main Methods:
- Cultured chick dorsal root ganglion (DRG) growth cones were used.
- Netrin-1's effect on growth cone collapse was assessed on different substrates (laminin-1, fibronectin).
- Integrin function was blocked, and intracellular cAMP levels were manipulated.
Main Results:
- Netrin-1 induced growth cone collapse in a substratum-specific manner, dependent on integrin activation.
- Netrin-1 directly binds to integrin α3 and α6 peptides.
- Netrin-1 increased growth cone cAMP levels, and collapse required both increased cAMP and integrin activation.
Conclusions:
- A novel mechanism for growth cone collapse involving integrins, netrin-1, and cAMP was identified.
- These interactions contribute to the intricate process of axon guidance.
- Substratum-dependent signaling pathways modulate growth cone responses to guidance cues.
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