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Retrograde semaphorin-plexin signalling drives homeostatic synaptic plasticity
Brian O Orr1, Richard D Fetter1, Graeme W Davis1
1Department of Biochemistry and Biophysics, University of California, San Francisco, San Francisco, California 94158, USA.
Nature
|September 28, 2017
Summary
Semaphorin 2b (Sema2b) acts on presynaptic plexin B (PlexB) receptors to control neurotransmitter release, stabilizing neural activity. This pathway regulates presynaptic plasticity, offering insights into neurological disease mechanisms.
Area of Science:
- Neuroscience
- Molecular Biology
- Developmental Biology
Background:
- Homeostatic signaling maintains stable yet flexible neural activity and behavior.
- Presynaptic homeostatic plasticity is a conserved mechanism across species, crucial for understanding neurological disorders.
- Semaphorin-plexin signaling is known for its role in axon guidance during development and is also present in the adult brain.
Purpose of the Study:
- To elucidate the molecular mechanisms of retrograde homeostatic control of neurotransmitter release.
- To investigate the role of semaphorin-plexin signaling in presynaptic homeostatic plasticity.
- To explore the relevance of these findings to neurological and psychiatric diseases.
Main Methods:
- Utilized Drosophila neuromuscular junction as a model system.
- Investigated the function of semaphorin 2b (Sema2b) as a target-derived signal.
- Analyzed the involvement of plexin B (PlexB) receptors, Mical, and actin regulation in presynaptic plasticity.
Main Results:
- Demonstrated that Sema2b acts on presynaptic PlexB receptors to mediate retrograde control of neurotransmitter release.
- Showed that Sema2b-PlexB signaling regulates presynaptic homeostatic plasticity via Mical and oxoreductase-dependent actin control.
- Identified semaphorin-plexin signaling as a key regulator of synaptic transmission stability.
Conclusions:
- Semaphorin-plexin signaling is essential for stabilizing synaptic transmission in both developing and mature nervous systems.
- The identified pathway provides a molecular basis for understanding neurological diseases linked to altered neural function.
- Findings suggest potential therapeutic targets for neurological and psychiatric disorders.
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