SPTB (Spectrin Beta, Erythrocytic)
Key structural protein of the erythrocyte membrane skeleton; mutations cause hereditary spherocytosis and related hemolytic anemias.
Gene Information Card
| Symbol | SPTB |
|---|---|
| Full Name | Spectrin beta, erythrocytic |
| Gene Type | Protein coding |
| Chromosomal Location | 14q23.3 |
| NCBI Gene ID | 6710 ncbi.nlm.nih.gov/gene/6710 |
| Ensembl ID | ENSG00000100804 |
| UniProt ID | P11277 |
| OMIM ID | 182870 |
| HGNC ID | 11273 |
| Aliases | SPTB1, SPH2, EL3, HSI, SPH2A, SPH2B |
Description
SPTB encodes beta-spectrin, a cytoskeletal protein that forms heterodimers with alpha-spectrin to assemble the membrane skeleton of erythrocytes. This network maintains red blood cell shape, deformability, and mechanical stability. Mutations in SPTB are a common cause of hereditary spherocytosis (HS) and hereditary elliptocytosis (HE).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Hereditary spherocytosis type 2 (SPH2) | Deficient or dysfunctional beta-spectrin weakens the membrane skeleton, leading to loss of membrane surface area and spherocyte formation. | ClinVar, OMIM |
| Hereditary elliptocytosis type 3 (EL3) | Altered spectrin dimer self-association disrupts the membrane skeleton, causing elliptical red cells. | ClinVar, OMIM |
| Neonatal hemolytic anemia | Severe SPTB mutations can cause life-threatening hemolysis in newborns. | ClinVar, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Whole blood | 112.3 | High |
| Spleen | 18.2 | Medium |
| Bone marrow | 15.7 | Medium |
| Liver | 2.1 | Low |
| Brain | 0.5 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Erythrocytes | 112.3 | Primary red blood cells |
| K562 | 45.2 | Chronic myeloid leukemia cell line |
| HEL | 38.9 | Erythroleukemia cell line |
| TF-1 | 22.1 | Erythroid progenitor cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1732C>T (p.Arg578Ter) | Nonsense | ~5% of HS cases | Premature stop; loss of function |
| c.4978G>A (p.Gly1660Arg) | Missense | Rare | Disrupts spectrin dimer self-association; dominant negative |
| c.653-1G>A | Splice site | Rare | Exon skipping; frameshift and truncation |
| c.1A>G (p.Met1Val) | Missense | Rare | Loss of translation initiation; loss of function |
Mutation functional classification
Loss of Function (LOF)
Nonsense, frameshift, and splice-site mutations that reduce or abolish beta-spectrin protein levels.
Gain of Function (GOF)
Not described for SPTB.
Dominant Negative (DN)
Missense mutations affecting the spectrin dimer self-association region (e.g., p.Gly1660Arg) that interfere with normal spectrin network assembly.
View complete mutation data：
Gene Ontology (GO)
Pathways
• Erythrocyte membrane skeleton (Reactome: R-HSA-5621480)
• Spectrin tetramerization (Reactome: R-HSA-5621481)
Protein Summary
Beta-spectrin (UniProt P11277) is a 2,137-amino-acid protein that assembles into antiparallel heterodimers with alpha-spectrin. These dimers form tetramers and higher-order oligomers to create a flexible meshwork underlying the erythrocyte plasma membrane. The protein contains multiple spectrin repeats, an SH3 domain, and a C-terminal pleckstrin homology domain that anchors it to the membrane via protein 4.1 and ankyrin.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| SPTBN1 Knockout HEK293 Cell Line | EDJ-KQ2469 | Human | 6711 | Details Get a Quote |
| SPTBN5 Knockout HEK293 Cell Line | EDJ-KQ11055 | Human | 51332 | Details Get a Quote |
| SPTB Knockout HEK293 Cell Line | EDJ-KQ15501 | Human | 6710 | Details Get a Quote |
| SPTBN2 Knockout HEK293 Cell Line | EDJ-KQ15502 | Human | 6712 | Details Get a Quote |
| SPTBN4 Knockout HEK293 Cell Line | EDJ-KQ15504 | Human | 57731 | Details Get a Quote |
| SPTBN1 Knockout A-549 Cell Line | EDJ-KQ23030 | Human | 6711 | Details Get a Quote |
| SPTBN1 Knockout HCT 116 Cell Line | EDJ-KQ23031 | Human | 6711 | Details Get a Quote |
| SPTB Knockout HCT 116 Cell Line | EDJ-KQ47206 | Human | 6710 | Details Get a Quote |
| SPTBN1 Knockout HeLa Cell Line | EDJ-KQ21676 | Human | 6711 | Details Get a Quote |
| SPTBN2 Knockout HCT 116 Cell Line | EDJ-KQ45066 | Human | 6712 | Details Get a Quote |
| SPTBN2 Knockout A-549 Cell Line | EDJ-KQ46299 | Human | 6712 | Details Get a Quote |
| SPTBN2 Knockout HeLa Cell Line | EDJ-KQ46300 | Human | 6712 | Details Get a Quote |
| SPTBN4 Knockout A-549 Cell Line | EDJ-KQ46301 | Human | 57731 | Details Get a Quote |
| SPTBN4 Knockout HCT 116 Cell Line | EDJ-KQ46302 | Human | 57731 | Details Get a Quote |
| SPTB Knockout HeLa Cell Line | EDJ-KQ54560 | Human | 6710 | Details Get a Quote |
Displaying Records 1 To 15 Of 20 Records
