Syntaxin-binding protein 3 (STXBP3)
The protein contains 592 amino acids for an estimated molecular weight of 67764 Da.
Together with STX4 and VAMP2, may play a role in insulin-dependent movement of GLUT4 and in docking/fusion of intracellular GLUT4-containing vesicles with the cell surface in adipocytes. (updated: April 1, 2015)
Protein identification was indicated in the following studies:
- Goodman and co-workers. (2013) The proteomics and interactomics of human erythrocytes. Exp Biol Med (Maywood) 238(5), 509-518.
- Lange and co-workers. (2014) Annotating N termini for the human proteome project: N termini and Nα-acetylation status differentiate stable cleaved protein species from degradation remnants in the human erythrocyte proteome. J Proteome Res. 13(4), 2028-2044.
- Hegedűs and co-workers. (2015) Inconsistencies in the red blood cell membrane proteome analysis: generation of a database for research and diagnostic applications. Database (Oxford) 1-8.
- Wilson and co-workers. (2016) Comparison of the Proteome of Adult and Cord Erythroid Cells, and Changes in the Proteome Following Reticulocyte Maturation. Mol Cell Proteomics. 15(6), 1938-1946.
- Bryk and co-workers. (2017) Quantitative Analysis of Human Red Blood Cell Proteome. J Proteome Res. 16(8), 2752-2761.
- D'Alessandro and co-workers. (2017) Red blood cell proteomics update: is there more to discover? Blood Transfus. 15(2), 182-187.
- Chu and co-workers. (2018) Quantitative mass spectrometry of human reticulocytes reveal proteome-wide modifications during maturation. Br J Haematol. 180(1), 118-133.
Methods
The following articles were analysed to gather the proteome content of erythrocytes.
The gene or protein list provided in the studies were processed using the ID mapping API of Uniprot in September 2018. The number of proteins identified and mapped without ambiguity in these studies is indicated below.
Only Swiss-Prot entries (reviewed) were considered for protein evidence assignation.
| Publication | Identification 1 | Uniprot mapping 2 | Not mapped / Obsolete | TrEMBL | Swiss-Prot |
|---|---|---|---|---|---|
| Goodman (2013) | 2289 (gene list) | 2278 | 53 | 20599 | 2269 |
| Lange (2014) | 1234 | 1234 | 7 | 28 | 1224 |
| Hegedus (2015) | 2638 | 2622 | 0 | 235 | 2387 |
| Wilson (2016) | 1658 | 1528 | 170 | 291 | 1068 |
| d'Alessandro (2017) | 1826 | 1817 | 2 | 0 | 1815 |
| Bryk (2017) | 2090 | 2060 | 10 | 108 | 1942 |
| Chu (2018) | 1853 | 1804 | 55 | 362 | 1387 |
1 as available in the article and/or in supplementary material
2 uniprot mapping returns all protein isoforms as one entry
The compilation of older studies can be retrieved from the Red Blood Cell Collection database.
The data and differentiation stages presented below come from the proteomic study and analysis performed by our partners of the GReX consortium, more details are available in their published work.
This protein is annotated as membranous in Gene Ontology, is annotated as membranous in UniProt.
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| Variant | Description |
|---|---|
| dbSNP:rs2275344 | |
| dbSNP:rs1044136 | |
| dbSNP:rs1044137 |
Biological Process
Blood coagulation
Brain development
Cellular glucose homeostasis
Cellular response to interferon-gamma
Glucose transport
Insulin secretion
Intracellular protein transport
Membrane organization
Negative regulation of calcium ion-dependent exocytosis
Negative regulation of glucose import
Negative regulation of glucose import in response to insulin stimulus
Neurotransmitter secretion
Neutrophil degranulation
Platelet activation
Platelet aggregation
Protein heterooligomerization
Protein to membrane docking
Response to insulin
Vesicle docking involved in exocytosis
Vesicle-mediated transport
The reference OMIM entry for this protein is 608339
Syntaxin-binding protein 3; stxbp3
Unc18, c. elegans, homolog of, 3
Munc18-3
Munc18c
Platelet sec1 protein; psp
CLONING
Gengyo-Ando et al. (1996) cloned mouse Stxbp3, which they called Munc18-3. The deduced protein contains 592 amino acids. By screening a human fetal brain cDNA library using the mouse cDNA as probe, Gengyo-Ando et al. (1996) cloned STXBP3. The deduced 592-amino acid protein lacks hydrophobic sequences, suggesting that it is an intracellular cytosolic protein. Human and mouse STXBP3 share 91% amino acid identity. Northern blot analysis of mouse tissues detected a 2.8-kb transcript in all tissues examined. Using an antiplatelet antibody to screen an expression library developed from a leukemia cell line that expressed platelet proteins, followed by screening a megakaryocytic cell line cDNA library, Reed et al. (1999) cloned STXBP3, which they called PSP. The deduced 592-amino acid protein has a calculated molecular mass of 68 kD and contains sequence motifs for protein kinase C (PKC; see 176982) and casein kinase II (see 115441) phosphorylation. STXBP3 was predicted to be a hydrophilic protein. Northern blot analysis detected a STXBP3 transcript of about 2.7 kb in 3 megakaryocytic cell lines. Western blot analysis detected a 68-kD protein in platelet detergent extracts. STXBP3 partitioned with the cytosolic platelet fraction, with small amounts in the particulate or membrane fraction.GENE FUNCTION
Reed et al. (1999) found that STXBP3 was phosphorylated in vivo in permeabilized platelets activated by thrombin (176930). Phosphorylation occurred within 1 minute and increased after 10 minutes of stimulation. No phosphorylation was detected in nonactivated cells. Phosphorylation was blocked by a PKC inhibitor.MAPPING
The International Radiation Hybrid Mapping Consortium mapped the STXBP3 gene to chromosome 1 (TMAP SHGC-75260).ANIMAL MODEL
To clarify the physiologic function of STXBP3 in insulin-stimulated GLUT4 (SLC2A4; 138190) exocytosis, Kanda et al. (2005) generated mouse embryos deficient in the syntaxin-4 (see 186591)-binding protein Stxbp3 and developed Stxbp3 -/- adipocytes from their mesenchymal fibroblasts. The insulin-induced appearance of Glut4 at the cell surface was enhanced in Stxbp3 -/- adipocytes compared to +/+ cells. Wortmannin, an inhibitor of PI3K, inhibited insulin-stimulated Glut4 externalization in +/+ but not -/- adipocytes. Kanda et al. (2005) suggested that disruption of the interaction between syntaxin-4 and STXBP3 in adipocytes might result in enhancement of insulin-stimulated GLUT4 externalization. ... More on the omim web site
Feb. 2, 2018: Protein entry updated
Automatic update: Uniprot description updated
Dec. 19, 2017: Protein entry updated
Automatic update: Uniprot description updated
March 16, 2016: Protein entry updated
Automatic update: OMIM entry 608339 was added.