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Updated: Jun 27, 2026
09:07
Genetic Manipulation of Cerebellar Granule Neurons In Vitro and In Vivo to Study Neuronal Morphology and Migration
Published on: March 17, 2014
O-GLcNAc post-translational modifications regulate the entry of neurons into an axon branching program
Herb Francisco1, Katherine Kollins, Neal Varghis
1Department of Neurobiology, Drexel University College of Medicine, Philadelphia, Pennsylvania 19129, USA.
Developmental Neurobiology
|December 17, 2008
Summary
O-linked N-acetylglucosamine (O-GlcNAc) modifications influence neuronal development by regulating axon morphology. Modulating O-GlcNAc levels impacts axon branching and filopodia formation in developing neurons.
Area of Science:
- Neuroscience
- Cell Biology
- Biochemistry
Background:
- Neuronal proteins undergo post-translational O-linked N-acetylglucosamine (O-GlcNAc) modification.
- The role of O-GlcNAc in neuronal development remains largely unknown.
- O-GlcNAc modifications occur on serine and threonine residues in both cytosolic and nuclear proteins.
Purpose of the Study:
- To investigate the cellular functions and impact of O-GlcNAc modifications during neuronal development.
- To determine how O-GlcNAc levels affect neuronal morphology, including axon branching and filopodia formation.
Main Methods:
- Immunostaining of O-GlcNAc-modified proteins in cultured primary chicken forebrain neurons.
- Overexpression of O-GlcNAcase (enzyme removing O-GlcNAc) to alter O-GlcNAc levels.
- Pharmacological inhibition of O-GlcNAcase using specific inhibitors (9d, PUGNAc).
- Treatment with forskolin (adenylyl cyclase activator) to study downstream signaling pathways.
Main Results:
- O-GlcNAc-modified proteins show non-uniform distribution in neurons, localizing to the cell body, axons, and filopodia.
- Increased O-GlcNAcase activity enhanced axon branching and axonal filopodia.
- Inhibition of O-GlcNAcase reduced axonal filopodia but did not affect axon length or branching.
- O-GlcNAcase inhibition suppressed forskolin-induced axon branching and altered phosphorylation of PKA substrates.
Conclusions:
- O-GlcNAc modification plays a significant role in regulating neuronal development and axon morphology.
- O-GlcNAc levels dynamically influence key aspects of neuronal structure, such as axon branching and filopodia dynamics.
- This study provides the first evidence for O-GlcNAc-specific roles in primary neuronal development.
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