3PUJ

Crystal structure of the MUNC18-1 and SYNTAXIN4 N-Peptide complex

Summary for 3PUJ

• Entry DOI: 10.2210/pdb3puj/pdb
• Descriptor: Syntaxin-binding protein 1, Syntaxin-4 N-terminal peptide (2 entities in total)
• Functional Keywords: membrane trafficking, sm protein, syntaxin, snare proteins, syntaxin binding protein, endocytosis-exocytosis complex, endocytosis/exocytosis
• Biological source: Rattus norvegicus (rat); More
• Cellular location: Cytoplasm: P61765; Cell membrane; Single-pass type IV membrane protein (Potential): P70452
• Total number of polymer chains: 4
• Total formula weight: 138022.47

Authors

Hu, S.-H.,Christie, M.P.,Saez, N.J.,Latham, C.F.,Jarrott, R.,Lua, L.H.L.,Collins, B.M.,Martin, J.L. (deposition date: 2010-12-05, release date: 2011-01-19, Last modification date: 2023-11-01)

Primary citation

Hu, S.-H.,Christie, M.P.,Saez, N.J.,Latham, C.F.,Jarrott, R.,Lua, L.H.L.,Collins, B.M.,Martin, J.L.
Possible roles for Munc18-1 domain 3a and Syntaxin1 N-peptide and C-terminal anchor in SNARE complex formation
Proc.Natl.Acad.Sci.USA, 108:1040-1045, 2011

PubMed Abstract: Munc18-1 and Syntaxin1 are essential proteins for SNARE-mediated neurotransmission. Munc18-1 participates in synaptic vesicle fusion via dual roles: as a docking/chaperone protein by binding closed Syntaxin1, and as a fusion protein that binds SNARE complexes in a Syntaxin1 N-peptide dependent manner. The two roles are associated with a closed-open Syntaxin1 conformational transition. Here, we show that Syntaxin N-peptide binding to Munc18-1 is not highly selective, suggesting that other parts of the SNARE complex are involved in binding to Munc18-1. We also find that Syntaxin1, with an N peptide and a physically anchored C terminus, binds to Munc18-1 and that this complex can participate in SNARE complex formation. We report a Munc18-1-N-peptide crystal structure that, together with other data, reveals how Munc18-1 might transit from a conformation that binds closed Syntaxin1 to one that may be compatible with binding open Syntaxin1 and SNARE complexes. Our results suggest the possibility that structural transitions occur in both Munc18-1 and Syntaxin1 during their binary interaction. We hypothesize that Munc18-1 domain 3a undergoes a conformational change that may allow coiled-coil interactions with SNARE complexes.

PubMed: 21193638
DOI: 10.1073/pnas.0914906108

Experimental method

X-RAY DIFFRACTION (3.313 Å)