A secreted complement-control-related protein ensures acetylcholine receptor clustering
Marie Gendrel1, Georgia Rapti, Janet E Richmond
1ENS, Biology Department, Paris, F-75005 France.
Nature
|October 2, 2009
Summary
A novel extracellular scaffold, comprising LEV-9 and LEV-10 proteins, is essential for clustering acetylcholine receptors at neuromuscular junctions. This finding suggests a direct role for complement control protein (CCP) domains in synaptic organization, independent of immune functions.
Area of Science:
- Neuroscience
- Molecular Biology
- Developmental Biology
Background:
- Efficient neurotransmission requires precise alignment of presynaptic and postsynaptic structures.
- Receptor localization at synapses typically involves intracellular scaffolding, but extracellular mechanisms are also proposed.
- The precise role of extracellular interactions in organizing postsynaptic domains in vivo remains unclear.
Purpose of the Study:
- To investigate the molecular mechanisms underlying acetylcholine receptor clustering at neuromuscular junctions.
- To identify novel proteins involved in the organization of postsynaptic domains.
- To explore the function of extracellular scaffolds in synaptic organization.
Main Methods:
- Genetic analysis in Caenorhabditis elegans.
- Biochemical interaction studies.
- Immunohistochemistry and protein localization assays.
Main Results:
- Identified a novel extracellular scaffold essential for acetylcholine receptor clustering at neuromuscular junctions.
- Demonstrated that LEV-9 (secreted) and LEV-10 (transmembrane) proteins are interdependent for synaptic localization of acetylcholine receptors.
- Showed that LEV-9 utilizes eight complement control protein (CCP) domains for its function.
Conclusions:
- An extracellular scaffold involving LEV-9 and LEV-10 is critical for acetylcholine receptor clustering in C. elegans.
- The study reveals a novel, non-immune function for CCP domains in synaptic organization.
- Suggests that mammalian CCP proteins may directly organize synapses, independent of immune roles.
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