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Updated: Sep 15, 2025
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Simultaneous Intracellular Recording of a Lumbar Motoneuron and the Force Produced by its Motor Unit in the Adult Mouse In vivo
Published on: December 5, 2012
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Structural insights into wiring specificity in the neuromuscular system through the Beat-Side complex
Jessica M Priest1,2,3, Ruiling Zhang2,4,5, Agnieszka M Olechwier1,2,3
1Department of Biochemistry and Molecular Biology, The University of Chicago, Chicago, IL 60637, USA.
Biorxiv : the Preprint Server for Biology
|July 15, 2025
Summary
The Beaten Path (Beat) and Sidestep (Side) proteins guide nervous system assembly. This study reveals their structure and shows Beat-Ia and Side interaction is crucial for motor neuron-muscle connections in Drosophila.
Area of Science:
- Neuroscience
- Molecular Biology
- Structural Biology
Background:
- Nervous system assembly relies on cell surface receptors for guidance and connectivity.
- Beaten Path (Beat) and Sidestep (Side) proteins in Drosophila function as axon guidance receptor-cue pairs and influence optic lobe synaptic specificity.
Purpose of the Study:
- To elucidate the molecular basis and specificity of interactions between Beat and Side protein families.
- To determine the structural basis of Beat-Vc and Side-VI binding.
Main Methods:
- Determined the crystal structure of the Beat-Vc and Side-VI complex.
- Engineered and validated point mutations to disrupt Beat-Side binding using a structure-based approach.
- Utilized mutant variants in developing Drosophila larvae to assess functional consequences.
Main Results:
- The first structure of a Beat-Side complex (Beat-Vc bound to Side-VI) was determined, revealing a binding topology similar to other neuronal immunoglobulin superfamily receptors.
- Structure-based mutations successfully disrupted Beat-Side binding.
- Disruption of Beat-Ia and Side interaction in vivo impaired motor neuron-muscle connectivity in developing Drosophila.
Conclusions:
- The structure of Beat-Vc bound to Side-VI provides insights into the molecular recognition mechanisms of these neuronal Ig superfamily receptors.
- Specific Beat-Side interactions are essential for establishing correct motor neuron connectivity during nervous system development in Drosophila.
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