Munc-18 Mouse, Unlabeled, Clone: 31, BD

There are two Munc-18 isoforms: Munc-18-1 and Munc-18-2. Munc-18-1 (n-sec1 or rb-sec1; 68 kDa) is a neuronal protein that binds tightly to syntaxin 1 and functions in synaptic vesicle exocytosis. Munc-18-2 exhibits 63% amino acid sequence identity with Munc-18-1. Although Munc-18-2 is expressed in most tissues, Munc-18-1 is primarily expressed in brain. Both forms of Munc-18 bind tightly to syntaxins 1A, 2, and 3, but not to syntaxin 4. Syntaxin 1A is a plasma membrane protein implicated in synaptic vesicle docking. Following calcium entry into the presynaptic nerve terminal, the neurotransmitter-containing synaptic vesicle fuses with the plasma membrane at a region known as the active zone. Thus, by virtue of its interaction with syntaxin 1A, Munc-18-1 is thought to have an essential function in neurotransmitter release.