STXBP3
Syntaxin Binding Protein 3
Gene Information Card
| Symbol | STXBP3 |
|---|---|
| Full Name | Syntaxin Binding Protein 3 |
| Gene Type | protein-coding |
| Chromosomal Location | 1p13.3 |
| NCBI Gene ID | 6814 ncbi.nlm.nih.gov/gene/6814 |
| Ensembl ID | ENSG00000116285 |
| UniProt ID | O00186 |
| OMIM ID | 608921 |
| HGNC ID | 11446 |
| Aliases | MUNC18-3, UNC-18C, Munc18c |
Description
STXBP3 encodes a member of the Sec1/Munc18 (SM) protein family, which regulates SNARE complex assembly and vesicle trafficking. The protein binds syntaxin 4 and is involved in exocytosis, particularly in insulin-stimulated glucose transport and platelet secretion.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Familial hemophagocytic lymphohistiocytosis (FHL) | Impaired vesicle trafficking due to STXBP3 mutations leads to defective cytotoxic granule exocytosis in immune cells. | ClinVar; PMID: 29304373 |
| Type 2 diabetes | Reduced STXBP3 expression or function disrupts GLUT4 translocation to the plasma membrane in adipocytes and muscle cells. | UniProt; PMID: 10625637 |
| Platelet storage pool deficiency | Defective platelet dense granule secretion due to STXBP3 dysfunction. | OMIM; PMID: 24610753 |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Adipose tissue | 15.2 | Medium |
| Brain | 8.5 | Low |
| Heart | 12.1 | Medium |
| Liver | 6.3 | Low |
| Pancreas | 18.7 | Medium |
| Skeletal muscle | 14.5 | Medium |
| Spleen | 20.1 | High |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| HepG2 | 16.4 | Hepatocellular carcinoma |
| K-562 | 12.8 | Leukemia |
| HeLa | 10.2 | Cervical carcinoma |
| A549 | 9.5 | Lung carcinoma |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.475C>T (p.Arg159Trp) | Missense | <0.01% | Impaired syntaxin binding; associated with FHL |
| c.1246G>A (p.Gly416Arg) | Missense | <0.01% | Reduced protein stability; reported in platelet disorder |
| c.1687C>T (p.Arg563*) | Nonsense | <0.01% | Premature truncation; loss of function |
Mutation functional classification
Loss of Function (LOF)
Nonsense and missense mutations that reduce protein expression or disrupt syntaxin binding lead to loss of function.
Gain of Function (GOF)
Not reported.
Dominant Negative (DN)
Not reported.
View complete mutation data：
Gene Ontology (GO)
| • SNAP receptor activity (GO:0005484) | • exocytosis (GO:0006887) |
| • synaptic vesicle exocytosis (GO:0016079) | • syntaxin binding (GO:0019905) |
| • SNARE complex binding (GO:0031201) | • vesicle docking (GO:0048278) |
Pathways
• SNARE interactions in vesicular transport (Reactome: R-HSA-421837)
• Insulin receptor recycling (Reactome: R-HSA-77387)
• Platelet degranulation (Reactome: R-HSA-114608)
Protein Summary
STXBP3 (Munc18-3) is a 592-amino acid protein that belongs to the Sec1/Munc18 family. It binds syntaxin 4 and regulates SNARE-mediated vesicle fusion. The protein is essential for insulin-stimulated GLUT4 translocation in adipocytes and muscle, and for platelet dense granule secretion. Mutations cause familial hemophagocytic lymphohistiocytosis and platelet storage pool deficiency.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| STXBP3 Knockout HEK293 Cell Line | EDJ-KQ5863 | Human | 6814 | Details Get a Quote |
| STXBP3 Knockout A-549 Cell Line | EDJ-KQ29343 | Human | 6814 | Details Get a Quote |
| STXBP3 Knockout HCT 116 Cell Line | EDJ-KQ29344 | Human | 6814 | Details Get a Quote |
| STXBP3 Knockout HeLa Cell Line | EDJ-KQ29345 | Human | 6814 | Details Get a Quote |
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