Syntaxin

Syntaxins are a family of membrane integrated Q-SNARE proteins participating in exocytosis. Syntaxins possess a single C-terminal transmembrane domain, a SNARE domain (known as H3), and an N-terminal regulatory domain (Habc). This particular structure is that of the N-terminal domain determined by solution NMR. The N-terminal Habc domain is formed by 3 α-helices and when collapsed onto its own H3 helix forms an inactive "closed" syntaxin conformation.