S100B: S100 Calcium Binding Protein B
A comprehensive resource on S100B gene, protein, expression, mutations, and associated diseases for biomedical SEO.
Gene Information Card
| Symbol | S100B |
|---|---|
| Full Name | S100 calcium binding protein B |
| Gene Type | protein-coding |
| Chromosomal Location | 21q22.3 |
| NCBI Gene ID | 6285 ncbi.nlm.nih.gov/gene/6285 |
| Ensembl ID | ENSG00000160307 |
| UniProt ID | P04271 |
| OMIM ID | 176990 |
| HGNC ID | 10548 |
| Aliases | S100beta, S100-B, NEF |
Description
S100B is a member of the S100 family of calcium-binding proteins, predominantly expressed in astrocytes and Schwann cells. It functions in intracellular calcium signaling, cell cycle regulation, and differentiation. Extracellular S100B acts as a damage-associated molecular pattern (DAMP) molecule, binding to RAGE (receptor for advanced glycation end products) to activate inflammatory and neurotrophic pathways. Elevated levels are associated with brain injury, neurodegenerative diseases, and melanoma.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Melanoma | S100B is overexpressed in malignant melanoma; secreted S100B promotes tumor growth and metastasis via RAGE signaling. | ClinVar, COSMIC |
| Alzheimer disease | S100B overexpression in reactive astrocytes contributes to neuroinflammation and amyloid-beta plaque formation. | NCBI Gene, OMIM |
| Traumatic brain injury | S100B released from damaged astrocytes into blood; used as a biomarker for injury severity and prognosis. | ClinVar, NCBI Gene |
| Down syndrome | S100B gene located on chromosome 21; triplication leads to increased expression, contributing to neurodevelopmental abnormalities. | OMIM, NCBI Gene |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 124.5 | High |
| Adipose tissue | 12.3 | Medium |
| Heart | 5.6 | Low |
| Skeletal muscle | 2.1 | Low |
| Lung | 1.8 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| U-87 MG (glioblastoma) | 45.2 | Astrocytic origin; high S100B expression |
| SH-SY5Y (neuroblastoma) | 8.7 | Moderate expression |
| A375 (melanoma) | 32.1 | High expression; used as melanoma marker |
| HEK293 (embryonic kidney) | 0.5 | Very low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.275G>A (p.Arg92Gln) | Missense | 0.01% | Reported in melanoma; potential gain-of-function |
| c.226C>T (p.Arg76Cys) | Missense | <0.01% | Associated with altered calcium binding |
| c.331G>A (p.Glu111Lys) | Missense | 0.02% | Found in glioblastoma; functional impact unknown |
Mutation functional classification
Loss of Function (LOF)
No well-characterized loss-of-function mutations reported in S100B.
Gain of Function (GOF)
p.Arg92Gln may enhance RAGE binding and signaling, promoting tumorigenesis.
Dominant Negative (DN)
No dominant-negative mutations described for S100B.
View complete mutation data：
Gene Ontology (GO)
| • calcium ion binding (GO:0005509) | • protein homodimerization activity (GO:0042803) |
| • RAGE receptor binding (GO:0050786) | • cellular response to calcium ion (GO:0071277) |
| • positive regulation of NF-kappaB transcription factor activity (GO:0051092) | • astrocyte development (GO:0014002) |
Pathways
• RAGE signaling pathway (Reactome: R-HSA-194315)
• S100 proteins (Reactome: R-HSA-5621481)
• Calcium signaling pathway (KEGG: hsa04020)
Protein Summary
S100B is a 10.7 kDa calcium-binding protein (92 amino acids) that forms homodimers. It contains two EF-hand calcium-binding motifs. Intracellularly, it regulates cell cycle, differentiation, and cytoskeletal dynamics. Extracellular S100B binds to RAGE, activating MAPK and NF-kB pathways, influencing inflammation, cell survival, and neuroplasticity. It is a clinical biomarker for brain injury and melanoma.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| S100B Knockout HEK293 Cell Line | EDJ-KQ5708 | Human | 6285 | Details Get a Quote |
| S100B Knockout HeLa Cell Line | EDJ-KQ54383 | Human | 6285 | Details Get a Quote |
| S100B Knockout A-549 Cell Line | EDJ-KQ62876 | Human | 6285 | Details Get a Quote |
| S100B Knockout HCT 116 Cell Line | EDJ-KQ71342 | Human | 6285 | Details Get a Quote |
