4BON

The structure and super-organization of acetylcholine receptor-rapsyn complexes class B

Summary for 4BON

• Entry DOI: 10.2210/pdb4bon/pdb
• Related: 4BOG 4BOI 4BOO
• EMDB information: 2378
• Descriptor: ACETYLCHOLINE RECEPTOR SUBUNIT ALPHA, ACETYLCHOLINE RECEPTOR BETA SUBUNIT, ACETYLCHOLINE RECEPTOR DELTA SUBUNIT, ... (4 entities in total)
• Functional Keywords: transport protein, neurotransmitter receptor, clustering, synapse, neuromuscular junction, nicotinic, 43k
• Biological source: TORPEDO MARMORATA (MARBLED ELECTRIC RAY); More
• Cellular location: Cell junction, synapse, postsynaptic cell membrane; Multi-pass membrane protein: P02711
• Total number of polymer chains: 5
• Total formula weight: 279950.34

Authors

Zuber, B.,Unwin, N. (deposition date: 2013-05-21, release date: 2013-06-26, Last modification date: 2024-10-09)

Primary citation

Zuber, B.,Unwin, N.
Structure and Superorganization of Acetylcholine Receptor-Rapsyn Complexes.
Proc.Natl.Acad.Sci.USA, 110:10622-, 2013

PubMed Abstract: The scaffolding protein at the neuromuscular junction, rapsyn, enables clustering of nicotinic acetylcholine receptors in high concentration and is critical for muscle function. Patients with insufficient receptor clustering suffer from muscle weakness. However, the detailed organization of the receptor-rapsyn network is poorly understood: it is unclear whether rapsyn first forms a wide meshwork to which receptors can subsequently dock or whether it only forms short bridges linking receptors together to make a large cluster. Furthermore, the number of rapsyn-binding sites per receptor (a heteropentamer) has been controversial. Here, we show by cryoelectron tomography and subtomogram averaging of Torpedo postsynaptic membrane that receptors are connected by up to three rapsyn bridges, the minimum number required to form a 2D network. Half of the receptors belong to rapsyn-connected groups comprising between two and fourteen receptors. Our results provide a structural basis for explaining the stability and low diffusion of receptors within clusters.

PubMed: 23754381
DOI: 10.1073/PNAS.1301277110

Experimental method

ELECTRON MICROSCOPY (40 Å)