STX1A

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. Syntaxins also 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 (MIM 600565) which produces explosive exocytosis (Zhang et al., 1995 [PubMed 7622072]).[supplied by OMIM

STX1A

Plays an essential role in hormone and neurotransmitter calcium-dependent exocytosis and endocytosis (PubMed:26635000).
Part of the SNARE (Soluble NSF Attachment Receptor) complex composed of SNAP25, STX1A and VAMP2 which mediates the fusion of synaptic vesicles with the presynaptic plasma membrane. STX1A and SNAP25 are localized on the plasma membrane while VAMP2 resides in synaptic vesicles. The pairing of the three SNAREs from the N-terminal SNARE motifs to the C-terminal anchors leads to the formation of the SNARE complex, which brings membranes into close proximity and results in final fusion. Participates in the calcium-dependent regulation of acrosomal exocytosis in sperm (PubMed:23091057).
Also plays an important role in the exocytosis of hormones such as insulin or glucagon-like peptide 1 (GLP-1) (By similarity).

Biological Process calcium-ion regulated exocytosisIEA:Ensembl
Biological Process exocytosisManual Assertion Based On ExperimentIBA:GO_Central
Biological Process insulin secretionIEA:Ensembl
Biological Process intracellular protein transportManual Assertion Based On ExperimentIBA:GO_Central
Biological Process positive regulation of calcium ion-dependent exocytosisISS:UniProtKB
Biological Process positive regulation of catecholamine secretionISS:UniProtKB
Biological Process positive regulation of excitatory postsynaptic potentialIEA:Ensembl
Biological Process positive regulation of neurotransmitter secretionIEA:Ensembl
Biological Process positive regulation of norepinephrine secretionISS:UniProtKB
Biological Process protein localization to membraneIEA:Ensembl
Biological Process protein sumoylationManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process regulation of insulin secretionManual Assertion Based On ExperimentTAS:UniProtKB
Biological Process regulation of synaptic vesicle primingIEA:Ensembl
Biological Process response to gravityIEA:Ensembl
Biological Process secretion by cellManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process SNARE complex assemblyIEA:Ensembl
Biological Process synaptic vesicle dockingIEA:Ensembl
Biological Process synaptic vesicle endocytosisManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process synaptic vesicle exocytosisManual Assertion Based On ExperimentIDA:UniProtKB
Biological Process synaptic vesicle fusion to presynaptic active zone membraneManual Assertion Based On ExperimentIBA:GO_Central
Biological Process vesicle dockingManual Assertion Based On ExperimentIBA:GO_Central
Biological Process vesicle fusionManual Assertion Based On ExperimentIBA:GO_Central

Cytoplasmic vesicle, secretory vesicle, synaptic vesicle membrane
Synapse, synaptosome
Cell membrane
Colocalizes with KCNB1 at the cell membrane.
Isoform 2
Secreted

STX1A is located in the Williams-Beuren syndrome (WBS) critical region. WBS results from a hemizygous deletion of several genes on chromosome 7q11.23, thought to arise as a consequence of unequal crossing over between highly homologous low-copy repeat sequences flanking the deleted region.

Cytoplasmic: 1-265
Helical: 266-286
Extracellular: 287-288

Phosphorylated by CK2 (By similarity).
Phosphorylation at Ser-188 by DAPK1 significantly decreases its interaction with STXBP1.
Sumoylated, sumoylation is required for regulation of synaptic vesicle endocytosis.