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Cryo-EM structure of SNAP-SNARE assembly in 20S particle.

ABSTRACT: N-ethylmaleimide-sensitive factor (NSF) and ? soluble NSF attachment proteins (?-SNAPs) work together within a 20S particle to disassemble and recycle the SNAP receptor (SNARE) complex after intracellular membrane fusion. To understand the disassembly mechanism of the SNARE complex by NSF and ?-SNAP, we performed single-particle cryo-electron microscopy analysis of 20S particles and determined the structure of the ?-SNAP-SNARE assembly portion at a resolution of 7.35 Å. The structure illustrates that four ?-SNAPs wrap around the single left-handed SNARE helical bundle as a right-handed cylindrical assembly within a 20S particle. A conserved hydrophobic patch connecting helices 9 and 10 of each ?-SNAP forms a chock protruding into the groove of the SNARE four-helix bundle. Biochemical studies proved that this structural element was critical for SNARE complex disassembly. Our study suggests how four ?-SNAPs may coordinate with the NSF to tear the SNARE complex into individual proteins.

SUBMITTER: Zhou Q

PROVIDER: S-EPMC4423085 | biostudies-literature | 2015 May

REPOSITORIES: biostudies-literature

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Cryo-EM structure of SNAP-SNARE assembly in 20S particle.

Zhou Qiang Q Huang Xuan X Sun Shan S Li Xueming X Wang Hong-Wei HW Sui Sen-Fang SF

Cell research 20150424 5

N-ethylmaleimide-sensitive factor (NSF) and α soluble NSF attachment proteins (α-SNAPs) work together within a 20S particle to disassemble and recycle the SNAP receptor (SNARE) complex after intracellular membrane fusion. To understand the disassembly mechanism of the SNARE complex by NSF and α-SNAP, we performed single-particle cryo-electron microscopy analysis of 20S particles and determined the structure of the α-SNAP-SNARE assembly portion at a resolution of 7.35 Å. The structure illustrates ...[more]

PMID: 25906996

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