Dataset Information


Munc18-1 binds directly to the neuronal SNARE complex.

ABSTRACT: Both SM proteins (for Sec1/Munc18-like proteins) and SNARE proteins (for soluble NSF-attachment protein receptors) are essential for intracellular membrane fusion, but the general mechanism of coupling between their functions is unclear, in part because diverse SM protein/SNARE binding modes have been described. During synaptic vesicle exocytosis, the SM protein Munc18-1 is known to bind tightly to the SNARE protein syntaxin-1, but only when syntaxin-1 is in a closed conformation that is incompatible with SNARE complex formation. We now show that Munc18-1 also binds tightly to assembled SNARE complexes containing syntaxin-1. The newly discovered Munc18-1/SNARE complex interaction involves contacts of Munc18-1 with the N-terminal H(abc) domain of syntaxin-1 and the four-helical bundle of the assembled SNARE complex. Together with earlier studies, our results suggest that binding of Munc18-1 to closed syntaxin-1 is a specialization that evolved to meet the strict regulatory requirements of neuronal exocytosis, whereas binding of Munc18-1 to assembled SNARE complexes reflects a general function of SM proteins involved in executing membrane fusion.

SUBMITTER: Dulubova I 

PROVIDER: S-EPMC1815244 | BioStudies | 2007-01-01

REPOSITORIES: biostudies

Similar Datasets

2009-01-01 | S-EPMC2755887 | BioStudies
2018-01-01 | S-EPMC6320071 | BioStudies
2003-01-01 | S-EPMC140874 | BioStudies
2017-01-01 | S-EPMC5733584 | BioStudies
2018-01-01 | S-EPMC6254354 | BioStudies
1000-01-01 | S-EPMC3761595 | BioStudies
2020-01-01 | S-EPMC7470827 | BioStudies
2016-01-01 | S-EPMC4775345 | BioStudies
1000-01-01 | S-EPMC3406668 | BioStudies
2003-01-01 | S-EPMC1223584 | BioStudies