STX1B: Syntaxin-1B
A key regulator of synaptic vesicle exocytosis and neurotransmitter release
Gene Information Card
| Symbol | STX1B |
|---|---|
| Full Name | syntaxin 1B |
| Gene Type | protein-coding |
| Chromosomal Location | 16p11.2 |
| NCBI Gene ID | 112755 ncbi.nlm.nih.gov/gene/112755 |
| Ensembl ID | ENSG00000140937 |
| UniProt ID | P61266 |
| OMIM ID | 601485 |
| HGNC ID | 11442 |
| Aliases | STX1B1, STX1B2, syntaxin-1B |
Description
STX1B encodes syntaxin-1B, a member of the syntaxin family of proteins that are key components of the SNARE complex. Syntaxin-1B is primarily expressed in neurons and neuroendocrine cells, where it mediates the docking and fusion of synaptic vesicles with the presynaptic membrane, enabling the release of neurotransmitters. Mutations in STX1B are associated with various forms of epilepsy, including generalized epilepsy with febrile seizures plus (GEFS+) and developmental and epileptic encephalopathy (DEE).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Generalized epilepsy with febrile seizures plus (GEFS+) | Loss-of-function mutations impair SNARE complex assembly, reducing neurotransmitter release and increasing neuronal excitability | ClinVar, OMIM |
| Developmental and epileptic encephalopathy (DEE) | Heterozygous missense or nonsense mutations disrupt syntaxin-1B function, leading to severe early-onset seizures and developmental delay | ClinVar, OMIM |
| Febrile seizures (FS) | Rare variants in STX1B may lower seizure threshold during fever, though exact mechanism unclear | ClinVar |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 37.2 | High |
| Cerebral cortex | 42.1 | High |
| Cerebellum | 35.8 | High |
| Hippocampus | 40.5 | High |
| Spinal cord | 28.3 | Medium |
| Testis | 12.4 | Low |
| Pancreas | 8.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 45.6 | High expression; used in neuronal studies |
| SK-N-SH (neuroblastoma) | 38.2 | High expression |
| U-87 MG (glioblastoma) | 22.1 | Moderate expression |
| HEK293 (embryonic kidney) | 5.3 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.226C>T (p.Arg76*) | Nonsense | Rare | Loss of function; truncates protein, associated with GEFS+ |
| c.580G>A (p.Gly194Arg) | Missense | Rare | Dominant-negative effect; disrupts SNARE complex formation, linked to DEE |
| c.1A>G (p.Met1?) | Start loss | Rare | Loss of function; prevents translation initiation, associated with febrile seizures |
| c.437_438del (p.Leu146Profs*12) | Frameshift | Rare | Loss of function; premature stop codon, reported in epilepsy |
Mutation functional classification
Loss of Function (LOF)
Nonsense, frameshift, and start-loss mutations reduce or abolish syntaxin-1B protein expression or function, impairing synaptic vesicle fusion.
Gain of Function (GOF)
Not reported for STX1B; gain-of-function mechanisms are not established.
Dominant Negative (DN)
Missense mutations (e.g., p.Gly194Arg) produce a defective protein that interferes with wild-type syntaxin-1B, disrupting SNARE complex assembly.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Neurotransmitter release cycle (Reactome: R-HSA-112310)
• SNARE interactions in vesicular transport (KEGG: hsa04130)
• Synaptic vesicle cycle (KEGG: hsa04721)
Protein Summary
Syntaxin-1B is a 288-amino-acid protein (UniProt P61266) that localizes to the plasma membrane of presynaptic terminals. It contains a C-terminal transmembrane domain and a SNARE motif that binds synaptobrevin and SNAP-25 to form the core SNARE complex. This complex mediates the fusion of synaptic vesicles with the presynaptic membrane, a critical step in neurotransmitter release. Syntaxin-1B is highly homologous to syntaxin-1A but is encoded by a distinct gene (STX1B).
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| STX1B Knockout HEK293 Cell Line | EDJ-KQ7394 | Human | 112755 | Details Get a Quote |
| STX1B Knockout A-549 Cell Line | EDJ-KQ32547 | Human | 112755 | Details Get a Quote |
| STX1B Knockout HeLa Cell Line | EDJ-KQ57897 | Human | 112755 | Details Get a Quote |
| STX1B Knockout HCT 116 Cell Line | EDJ-KQ74817 | Human | 112755 | Details Get a Quote |
