Rapsyn may function as a link between the acetylcholine receptor and the agrin-binding dystrophin-associated glycoprotein complex

@article{Apel1995RapsynMF,
  title={Rapsyn may function as a link between the acetylcholine receptor and the agrin-binding dystrophin-associated glycoprotein complex},
  author={Elizabeth D. Apel and Steven L. Roberds and Kevin P. Campbell and John Paul Merlie},
  journal={Neuron},
  year={1995},
  volume={15},
  pages={115-126}
}

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Agrin Regulates Rapsyn Interaction with Surface Acetylcholine Receptors, and This Underlies Cytoskeletal Anchoring and Clustering*

TLDR
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Acetylcholine receptors are required for agrin‐induced clustering of postsynaptic proteins

TLDR
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Interactions of the Rapsyn RING-H2 Domain with Dystroglycan*

TLDR
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Differential targeting of components of the dystrophin complex to the postsynaptic membrane

TLDR
This study provides the first evidence for a separate targeting of the various components of the dystrophin‐associated protein complex and a step‐by‐step assembly at the postsynaptic membrane.

Dystroglycan overexpression in vivo alters acetylcholine receptor aggregation at the neuromuscular junction.

TLDR
Overexpressed dystroglycan altered AChR aggregation in a rostral-caudal gradient, consistent with the sequential development of neuromuscular synapses along the embryo, and supports the hypothesis that dystoglycan is not the myotube-associated specificity component, (MASC) a putative coreceptor needed for agrin to activate muscle-specific kinase (MuSK) and signal ACh R aggregation.

Non-neural agrin codistributes with acetylcholine receptors during early differentiation of Torpedo electrocytes.

TLDR
Agrin, an extracellular matrix protein synthesized by nerves and muscles, is known to promote the clustering of acetylcholine receptors and other synaptic proteins in cultured myotubes, and the existence of more than one agrin receptor is postulated to account for the action of agrin variants at different stages of the differentiation of the postsynaptic membrane in Torpedo electrocytes.

Overexpression of rapsyn inhibits agrin-induced acetylcholine receptor clustering in muscle cells

TLDR
The results indicate that rapsyn expression is essential for agrin-induced AChR clustering but that its overexpression inhibits this pathway.

The postsynaptic submembrane machinery at the neuromuscular junction: Requirement for rapsyn and the utrophin/dystrophin-associated complex

TLDR
The current understanding of the role of the postsynaptic-submembrane machinery involving rapsyn and the utrophin-associated complex at the neuromuscular synapse is reviewed.
...

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