Related Experiment Videos
Developmental expression of dynamin in the chick retinotectal system
1Institute of Anatomy and Special Embryology, University Fribourg, Fribourg, Switzerland.
Summary
Dynamin I, crucial for synaptic vesicle endocytosis, is expressed after synapse formation, not during early axon growth. This suggests its primary role in synaptogenesis, not axonogenesis.
Area of Science:
- Neuroscience
- Cell Biology
- Developmental Biology
Background:
- Dynamin I is a GTPase involved in synaptic vesicle endocytosis.
- Its role in axonal outgrowth and synaptogenesis is proposed.
- Understanding its developmental expression is key to elucidating its function.
Purpose of the Study:
- To investigate the temporal and spatial expression patterns of dynamin I during neuronal development.
- To compare dynamin I expression with presynaptic proteins SV2, synaptotagmin, and syntaxin in the chick visual pathway.
Main Methods:
- Western blotting of retina and tectum at various embryonic days (E7-E11) and postnatal stages.
- Immunofluorescence staining of retinal ganglion cell axons and visual pathway.
Main Results:
- Synaptotagmin and syntaxin increased steadily from E7 to E11, while dynamin I showed no detectable increase.
- SV2, synaptotagmin, and syntaxin were present in axons from E4 onwards.
- Dynamin I was undetectable before synapse formation, appearing later in development.
Conclusions:
- Dynamin I expression is upregulated after synapse formation, unlike early-expressed presynaptic proteins.
- This suggests dynamin I's primary function is in synaptogenesis and synaptic vesicle cycling, rather than axonogenesis.