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Preparation of Synaptic Plasma Membrane and Postsynaptic Density Proteins Using a Discontinuous Sucrose Gradient
Published on: September 3, 2014
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SAD-1 kinase controls presynaptic phase separation by relieving SYD-2/Liprin-α autoinhibition
Nathan A McDonald1, Li Tao1, Meng-Qiu Dong2
1Department of Biology, Stanford University, Stanford, California, United States of America.
Plos Biology
|December 4, 2023
Summary
Scientists discovered that the SAD-1 kinase controls the phase separation of SYD-2/Liprin-α, a crucial protein for active zone assembly in developing synapses. This phosphorylation is essential for proper presynaptic development.
Area of Science:
- Neuroscience
- Cell Biology
- Molecular Biology
Background:
- Synapse formation is critical for nervous system function.
- Active zone assembly in developing presynapses involves liquid-liquid phase separation.
- SYD-2/Liprin-α is a key scaffold protein in active zones.
Purpose of the Study:
- To investigate the regulation of SYD-2/Liprin-α phase separation during neuronal development.
- To identify kinases that control SYD-2/Liprin-α phase separation and presynaptic assembly.
Main Methods:
- Studied Caenorhabditis elegans models.
- Utilized phosphoproteomics to identify phosphorylation sites.
- Assessed presynaptic assembly in wild-type and mutant strains.
Main Results:
- Identified SAD-1 kinase as a regulator of SYD-2/Liprin-α phase separation.
- SAD-1 phosphorylation of SYD-2 on three critical sites activates phase separation.
- Impaired presynaptic assembly observed in sad-1 mutants; enhanced assembly with SAD-1 overactivation.
Conclusions:
- SAD-1 kinase phosphorylates SYD-2/Liprin-α at developing synapses, activating its phase separation.
- This phosphorylation event is crucial for initiating active zone assembly.
- Synaptic cell adhesion molecules recruit SAD-1 to nascent synapses, upstream of active zone formation.
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