Munc 18 (rb-sec1, n-sec1)

Peripheral membrane protein involved in vesicle docking and fusion

General Information

Munc 18 is an abundant neuronal protein that tightly binds to the synaptic fusion protein syntaxin 1. It is highly homologous to the C. elegans unc-18 gene product, and weakly related to the yeast sec1, sly1, and slp1 genes.
There are three munc 18 isoforms in mammals. Munc 18-1 or 18a, also referred to as rb-sec1, n-sec1, stxbp1 and p67, is primarily expressed in neurons. Munc 18-2 or 18b, also referred to as stxbp2, and Munc 18-3 or 18c are expressed ubiquitously.