2cjs
From Proteopedia
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, resolution 1.78Å | |||||||
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Ligands: | , , | ||||||
Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
Coordinates: | save as pdb, mmCIF, xml |
STRUCTURAL BASIS FOR A MUNC13-1 HOMODIMER- MUNC13-1- RIM HETERODIMER SWITCH: C2-DOMAINS AS VERSATILE PROTEIN-PROTEIN INTERACTION MODULES
Overview
C(2) domains are well characterized as Ca(2+)/phospholipid-binding modules, but little is known about how they mediate protein-protein interactions. In neurons, a Munc13-1 C(2)A-domain/RIM zinc-finger domain (ZF) heterodimer couples synaptic vesicle priming to presynaptic plasticity. We now show that the Munc13-1 C(2)A domain homodimerizes, and that homodimerization competes with Munc13-1/RIM heterodimerization. X-ray diffraction studies guided by nuclear magnetic resonance (NMR) experiments reveal the crystal structures of the Munc13-1 C(2)A-domain homodimer and the Munc13-1 C(2)A-domain/RIM ZF heterodimer at 1.44 A and 1.78 A resolution, respectively. The C(2)A domain adopts a beta-sandwich structure with a four-stranded concave side that mediates homodimerization, leading to the formation of an eight-stranded beta-barrel. In contrast, heterodimerization involves the bottom tip of the C(2)A-domain beta-sandwich and a C-terminal alpha-helical extension, which wrap around the RIM ZF domain. Our results describe the structural basis for a Munc13-1 homodimer-Munc13-1/RIM heterodimer switch that may be crucial for vesicle priming and presynaptic plasticity, uncovering at the same time an unexpected versatility of C(2) domains as protein-protein interaction modules, and illustrating the power of combining NMR spectroscopy and X-ray crystallography to study protein complexes.
About this Structure
2CJS is a Protein complex structure of sequences from Rattus norvegicus. Full crystallographic information is available from OCA.
Reference
Structural basis for a Munc13-1 homodimer to Munc13-1/RIM heterodimer switch., Lu J, Machius M, Dulubova I, Dai H, Sudhof TC, Tomchick DR, Rizo J, PLoS Biol. 2006 Jul;4(7):e192. PMID:16732694
Page seeded by OCA on Mon Mar 31 02:22:30 2008
Categories: Protein complex | Rattus norvegicus | Dai, H. | Dulubova, I. | Lu, J. | Machius, M. | Rizo, J. | Sudhof, T C. | Tomchick, D R. | Alternative splicing | C2 domain | Coiled coil | Exocytosis | Metal-binding | Munc13 | Neurotransmitter release | Neurotransmitter transport | Phorbol-ester binding | Protein-protein interaction | Rim | Synapse | Synaptosome | Transport | Zinc | Zinc finger