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Shh-ushing Midline Crossing through Remote Protein Transport
Eloísa Herrera1, Austen A Sitko2, Paola Bovolenta3
1Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas-Universidad Miguel Hernández, CSIC-UMH, Alicante, Spain.
Neuron
|January 19, 2018
Summary
Sonic hedgehog (Shh) plays a role in neural circuit formation. A new study reveals Shh prevents specific axons from crossing the midline at the optic chiasm via a trans-axonal mechanism.
Area of Science:
- Neuroscience
- Developmental Biology
- Molecular Biology
Background:
- Neural circuit formation relies on precise axonal guidance.
- The optic chiasm is a critical site for visual pathway development, involving midline crossing decisions.
Purpose of the Study:
- To elucidate novel mechanisms of Sonic hedgehog (Shh) in neural circuit formation.
- To identify the role of Shh in regulating axonal guidance at the optic chiasm.
Main Methods:
- Investigated Shh signaling pathways in retinal ganglion cells.
- Utilized genetic and imaging techniques to track axonal projections.
- Examined the interaction between Shh and Boc in axonal guidance.
Main Results:
- Identified a novel trans-axonal signaling mechanism involving Shh.
- Demonstrated that Shh from contralateral retinal ganglion cells inhibits ipsilateral axon crossing.
- Showed that Boc-expressing ipsilateral axons are prevented from crossing the midline by Shh.
Conclusions:
- Shh employs a trans-axonal mechanism to control midline crossing of specific axons.
- This finding reveals a new layer of regulation in visual system development.
- Highlights the intricate molecular interactions governing neural circuit assembly.
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