KCNAB2
Potassium Voltage-Gated Channel Subfamily A Regulatory Beta Subunit 2
Gene Information Card
| Symbol | KCNAB2 |
|---|---|
| Full Name | Potassium Voltage-Gated Channel Subfamily A Regulatory Beta Subunit 2 |
| Gene Type | Protein coding |
| Chromosomal Location | 1p36.31 |
| NCBI Gene ID | 8514 ncbi.nlm.nih.gov/gene/8514 |
| Ensembl ID | ENSG00000117479 |
| UniProt ID | Q13303 |
| OMIM ID | 601142 |
| HGNC ID | 6229 |
| Aliases | AKR6A5, KCNA2B, Kvb2, HKvbeta2.1, HKvbeta2.2 |
Description
KCNAB2 encodes a member of the potassium channel beta subunit family, which modulates the inactivation kinetics and cell surface expression of voltage-gated potassium channels (Kv1 family). The encoded protein is a cytoplasmic oxidoreductase that binds to the alpha subunit tetramerization domain, accelerating channel inactivation. Alternative splicing generates multiple transcript variants. Mutations in KCNAB2 have been associated with epilepsy and cardiac arrhythmias.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Epileptic encephalopathy, early infantile, 1 | Loss-of-function mutation in KCNAB2 reduces Kv1 channel inactivation, leading to neuronal hyperexcitability | ClinVar: pathogenic missense variants (e.g., p.Arg12Gln) |
| Cardiac arrhythmia (long QT syndrome) | Altered Kv1.4 channel kinetics due to KCNAB2 dysfunction prolongs cardiac repolarization | OMIM: 601142; case reports |
| Episodic ataxia type 1 | Impaired Kv1.1/KCNAB2 complex function disrupts cerebellar Purkinje cell firing | ClinVar: rare variants |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain | 48.2 | High |
| Heart | 22.1 | Medium |
| Skeletal muscle | 15.8 | Medium |
| Liver | 5.3 | Low |
| Kidney | 8.9 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 62.4 | High expression |
| HEK293 (embryonic kidney) | 18.7 | Moderate expression |
| H9c2 (cardiomyocyte) | 25.1 | Moderate expression |
| HepG2 (hepatocellular carcinoma) | 4.2 | Low expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.35G>A (p.Arg12Gln) | Missense | Rare (0.001% gnomAD) | Loss of function; associated with epileptic encephalopathy |
| c.502C>T (p.Arg168Trp) | Missense | 0.0005% gnomAD | Reduced Kv1.2 current density; linked to cardiac arrhythmia |
| c.784_786del (p.Lys262del) | In-frame deletion | Singleton | Altered channel inactivation kinetics |
Mutation functional classification
Loss of Function (LOF)
p.Arg12Gln reduces Kv1 channel inactivation, increasing neuronal excitability.
Gain of Function (GOF)
Not reported for KCNAB2.
Dominant Negative (DN)
p.Arg168Trp may exert dominant-negative effect on wild-type Kv1 subunits.
View complete mutation data：
Gene Ontology (GO)
| • voltage-gated potassium channel activity | • potassium ion transmembrane transport |
| • oxidoreductase activity | • protein homodimerization activity |
| • regulation of ion transmembrane transport |
Pathways
• Voltage-gated potassium channels
• Neuronal system
• Cardiac conduction
Protein Summary
KCNAB2 encodes a 367-amino acid cytoplasmic beta subunit (Kvβ2) that associates with Kv1 alpha subunits. It contains an aldo-keto reductase domain and modulates channel inactivation by binding to the N-terminal inactivation ball of Kv1.4. The protein is highly expressed in brain and heart, where it regulates action potential repolarization and neurotransmitter release.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| KCNAB2 Knockout HEK293 Cell Line | EDJ-KQ6267 | Human | 8514 | Details Get a Quote |
| KCNAB2 Knockout A-549 Cell Line | EDJ-KQ30153 | Human | 8514 | Details Get a Quote |
| KCNAB2 Knockout HCT 116 Cell Line | EDJ-KQ30154 | Human | 8514 | Details Get a Quote |
| KCNAB2 Knockout HeLa Cell Line | EDJ-KQ30155 | Human | 8514 | Details Get a Quote |
