Syntaxin-1A is a protein that in humans is encoded by the STX1A gene. Function Synaptic vesicles store neurotransmitters that are released during calcium-regulated exocytosis. The specificity of neurotransmitter release requires the localization of both synaptic vesicles and calcium channels to the presynaptic active zone. Syntaxins function in this vesicle fusion process. Syntaxin-1A is a member of the syntaxin superfamily. Syntaxins are nervous system-specific proteins implicated in the docking of synaptic vesicles with the presynaptic plasma membrane. Syntaxins possess a single C-terminal transmembrane domain, a SNARE [Soluble NSF (N-ethylmaleimide-sensitive fusion protein)-Attachment protein REceptor] domain (known as H3), and an N-terminal regulatory domain (Habc). Syntaxins bind synaptotagmin in a calcium-dependent fashion and interact with voltage dependent calcium and potassium channels via the C-terminal H3 domain. Syntaxin-1A is a key protein in ion channel regulation and synaptic exocytosis. Clinical significance Syntaxins serve as a substrate for botulinum neurotoxin type C, a metalloprotease that blocks exocytosis and has high affinity for a molecular complex that includes the alpha-latrotoxin receptor which produces explosive exocytosis. The expression level of STX1A is directly correlated with intelligence in Williams syndrome. Interactive pathway map Interactions STX1A has been shown to interact with: CPLX1, CFTR, NAPA, RNF40, SCNN1G, SLC6A1, SNAP-25, SNAP23, STXBP1, STXBP5, SYT1 UNC13B, VAMP2, and VAMP8. See also Syntaxin References Further reading External links