Single-vesicle fusion assay reveals Munc18-1 binding to the SNARE core is sufficient for stimulating membrane fusion

Jiajie Diao, Zengliu Su, Xiaobing Lu, Tae Young Yoon, Yeon Kyun Shin, Taekjip Ha

Research output: Contribution to journalArticlepeer-review

Abstract

Munc18, an essential regulatory protein for intracellular membrane fusion mediated by SNAREs, is known for stabilizing the closed conformation of syntaxin through the interaction with the N-terminal Habc domain (amino acids 28-146) of syntaxin. In addition, Munc18 accelerates membrane fusion and its interaction with SNARE core and the N-peptide (amino acids 1-24) of syntaxin is thought to be necessary for this function. Using the recently developed fluorescence resonance energy transfer assay to detect the fusion between two individual vesicles harboring cognate SNARE proteins, we studied the effect of Munc18 on the fusion induced by neuronal SNARE proteins by following the mixing of lipid molecules between the two vesicles. We found that Munc18-1 stimulates neuronal SNARE-mediated fusion not only with full-length syntaxin 1A but also with a truncated syntaxin 1A that is missing both the Habc domain and the N-peptide. The electron paramagnetic resonance analysis indicates that the SNARE core/Munc18 interaction is responsible for this stimulatory function and the membrane plays a role for establishing this interaction.

Original languageEnglish (US)
Pages (from-to)168-174
Number of pages7
JournalACS Chemical Neuroscience
Volume1
Issue number3
DOIs
StatePublished - Mar 17 2010
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Physiology
  • Cognitive Neuroscience
  • Cell Biology

Fingerprint Dive into the research topics of 'Single-vesicle fusion assay reveals Munc18-1 binding to the SNARE core is sufficient for stimulating membrane fusion'. Together they form a unique fingerprint.

Cite this