KCNA1: Potassium Voltage-Gated Channel Subfamily A Member 1
Key regulator of neuronal excitability and associated with episodic ataxia type 1
Gene Information Card
| Symbol | KCNA1 |
|---|---|
| Full Name | Potassium Voltage-Gated Channel Subfamily A Member 1 |
| Gene Type | Protein coding |
| Chromosomal Location | 12p13.32 |
| NCBI Gene ID | 3736 ncbi.nlm.nih.gov/gene/3736 |
| Ensembl ID | ENSG00000111262 |
| UniProt ID | Q09470 |
| OMIM ID | 176260 |
| HGNC ID | 6218 |
| Aliases | AEMK, EA1, HUK1, Kv1.1, MBK1, MK1, RBK1 |
Description
KCNA1 encodes the voltage-gated potassium channel Kv1.1, a member of the Shaker-related potassium channel family. This channel mediates the delayed rectifier potassium current, crucial for repolarization of action potentials in neurons and cardiac myocytes. Mutations in KCNA1 cause episodic ataxia type 1 (EA1), a neurological disorder characterized by episodes of incoordination and muscle twitching.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Episodic ataxia type 1 (EA1) | Loss-of-function mutations reduce potassium conductance, prolonging action potential duration and increasing neuronal excitability | ClinVar, OMIM |
| Myokymia (isolated) | Dominant-negative mutations impair channel function, leading to peripheral nerve hyperexcitability | ClinVar |
| Epilepsy (partial) | Missense mutations alter channel gating, predisposing to seizure activity | NCBI Gene, OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Brain (cerebellum) | 12.5 | High |
| Brain (cerebral cortex) | 8.3 | Medium |
| Heart | 4.1 | Low |
| Skeletal muscle | 2.0 | Low |
| Liver | 0.5 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| SH-SY5Y (neuroblastoma) | 15.2 | High expression |
| HEK293 (embryonic kidney) | 0.8 | Low endogenous expression |
| U-87 MG (glioblastoma) | 6.7 | Medium expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.677C>T (p.Thr226Met) | Missense | 2% | Reduced potassium current; associated with EA1 |
| c.1120G>A (p.Val374Ile) | Missense | 1% | Altered voltage dependence; myokymia |
| c.959delC (p.Pro320Leufs*12) | Frameshift | <0.1% | Loss of function; severe EA1 |
Mutation functional classification
Loss of Function (LOF)
Most EA1 mutations reduce or abolish potassium channel activity, leading to neuronal hyperexcitability.
Gain of Function (GOF)
Rare; some missense variants (e.g., p.Arg417Cys) show increased current amplitude in vitro.
Dominant Negative (DN)
Common; mutant subunits co-assemble with wild-type, impairing overall channel function.
View complete mutation data：
Gene Ontology (GO)
| • voltage-gated potassium channel activity (GO:0005249) | • potassium ion transport (GO:0006813) |
| • integral component of membrane (GO:0016021) | • regulation of ion transmembrane transport (GO:0034765) |
| • protein homooligomerization (GO:0051260) |
Pathways
• Potassium channels (Reactome: R-HSA-1296071)
• Voltage gated potassium channels (KEGG: hsa04010)
• Neuronal System (Reactome: R-HSA-112316)
Protein Summary
Kv1.1 is a 495-amino acid protein with six transmembrane domains (S1-S6), a voltage-sensing domain (S4), and a pore-forming loop. It assembles as a homotetramer or heterotetramer with other Kv1 subunits to form functional potassium channels. The channel is blocked by 4-aminopyridine and dendrotoxin. Post-translational modifications include N-glycosylation and phosphorylation, which modulate channel trafficking and activity.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| KCNA1 Knockout HEK293 Cell Line | EDJ-KQ5013 | Human | 3736 | Details Get a Quote |
| KCNA10 Knockout HEK293 Cell Line | EDJ-KQ5019 | Human | 3744 | Details Get a Quote |
| KCNA1 Knockout HeLa Cell Line | EDJ-KQ53692 | Human | 3736 | Details Get a Quote |
| KCNA10 Knockout HeLa Cell Line | EDJ-KQ53699 | Human | 3744 | Details Get a Quote |
| KCNA1 Knockout A-549 Cell Line | EDJ-KQ62170 | Human | 3736 | Details Get a Quote |
| KCNA10 Knockout A-549 Cell Line | EDJ-KQ62177 | Human | 3744 | Details Get a Quote |
| KCNA1 Knockout HCT 116 Cell Line | EDJ-KQ70656 | Human | 3736 | Details Get a Quote |
| KCNA10 Knockout HCT 116 Cell Line | EDJ-KQ70663 | Human | 3744 | Details Get a Quote |
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