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Published on: October 14, 2021
Microtubules and filaments in developing axons and optic stalk cells
1Department of Biological Sciences, Hunter College of the City University, New York, New York 10021.
Tissue & Cell
|January 1, 1971
Summary
Researchers studied fibrous structures in developing chick optic nerves. Early identification of nerve cells using neurofilaments may be unreliable due to similar structures in optic stalk cells.
Area of Science:
- Neuroscience
- Developmental Biology
- Cell Biology
Background:
- The developing optic nerve is crucial for visual system formation.
- Axon development involves complex cytoskeletal rearrangements, including neurofilaments and microtubules.
- Accurate identification of early neuronal structures is vital for understanding neural development.
Purpose of the Study:
- To investigate the fibrous structures, specifically neurofilaments and microtubules, in the developing chick optic nerve.
- To assess the reliability of using neurofilaments for identifying early nerve cells in the optic nerve.
Main Methods:
- Comparative analysis of optic nerve cross-sections from chick embryos at different developmental stages (3, 4, and 5 days).
- Microscopic examination of axon size, neurofilament presence, and microtubule density.
- Evaluation of fibrous structures in early optic stalk cells.
Main Results:
- Early ganglion cell axons (3-day embryos) contained both neurofilaments and microtubules.
- Very small axons appeared in later stages (4- and 5-day embryos).
- Microtubule density was consistent across axon sizes, except in very small axons which showed higher density per unit area.
- Filamentous structures resembling neurofilaments were observed in early optic stalk cells.
Conclusions:
- The presence of neurofilament-like structures in early optic stalk cells challenges the reliability of using 'neurofilaments' for identifying nascent nerve cells.
- Axon development in the optic nerve involves dynamic changes in cytoskeletal components.
- Further research is needed to refine markers for early neuronal identification.
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