The SNARE protein syntaxin-1 exists in two conformations during synaptic vesicle fusion, both of which can bind to Munc18-1: the "open" conformation in the SNARE complex and a "closed" conformation outside the SNARE complex.

SNARE complexes containing open syntaxin-1 and Munc18-1 are essential for exocytosis. A research team from the USA, Germany and the Netherlands generated knockin/knockout mice that expressed only open syntaxin-1B.

Syntaxin-1B^open mice were viable at first, but died of generalised seizures at the age of 2 – 3 months. Binding of Munc18-1 to syntaxin-1 was observed to be inhibited in syntaxin-1B^open synapses, and the size of the readily releasable vesicle pool was smaller. The rate of synaptic vesicle fusion, on the other hand, was extraordinarily increased.

The closed conformation of syntaxin-1 therefore seems to block the initiation of the synaptic vesicle fusion reaction, which is then mediated by SNARE-complex/Munc18-1 assemblies.

Related antibodies on antibodies-online.com:

Syntaxin-1

Syntaxin-1A

Munc18

N-ethylmaleimide-sensitive factor (ligand to SNARE)

Antibodies for the research area neurology: »Show antibodies