Protein / target
Potassium voltage-gated channel subfamily A member 5
Protein at a glance
Biological role
Delayed rectifier potassium channel
Strongest disease association
Atrial Fibrillation
Therapeutic position
Established drug target
Derived from structured UniProt, Open Targets and literature data on this page.
Protein profile
Canonical identity and biological annotation from UniProt.
Function overview
Voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes.
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Voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes. Forms tetrameric potassium-selective channels through which potassium ions pass in accordance with their electrochemical gradient. The channel alternates between opened and closed conformations in response to the voltage difference across the membrane. Can form functional homotetrameric channels and heterotetrameric channels that contain variable proportions of KCNA1, KCNA2, KCNA4, KCNA5, and possibly other family members as well; channel properties depend on the type of alpha subunits that are part of the channel (PubMed:12130714). Channel properties are modulated by cytoplasmic beta subunits that regulate the subcellular location of the alpha subunits and promote rapid inactivation (PubMed:12130714). Homotetrameric channels display rapid activation and slow inactivation (PubMed:12130714, PubMed:8505626). Required for normal electrical conduction including formation of the infranodal ventricular conduction system and normal action potential configuration, as a result of its interaction with XIRP2 (By similarity). May play a role in regulating the secretion of insulin in normal pancreatic islets
Subcellular location
Domains and Gene Ontology detail (43)Hide
Gene Ontology
- Ccell surface
- CGolgi apparatus
- Cintercalated disc
- Cintracellular canaliculus
- Cmembrane
- Cmembrane raft
- Cperinuclear region of cytoplasm
- Cplasma membrane
- Cpotassium channel complex
- Cvoltage-gated potassium channel complex
- CZ disc
- Falpha-actinin binding
Biological roles
What this protein does, drawn together from its UniProt function, Gene Ontology terms and Reactome pathways.
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Ion channel gating
- ·potassium ion transmembrane transport
Cell-cycle regulation
- ·positive regulation of G1/S transition of mitotic cell cycle
Concepts derived from UniProt GO Reactome — each badge above shows which sources supported that role.
Approved medicines with mapped indications
Approved therapies targeting this protein, grouped by what they are approved to treat — the disease-first view of the medicines below. Relationships come from the canonical approved-indication graph (ChEMBL phase-4), the same source as the drug cards.
7 medicines meet Open Targets' target-level approved-medicine definition; the 2 shown here are those on this page with a canonical approved disease indication in the graph. Approved indications from ChEMBL (phase-4), via the canonical drug→disease graph.
Drugs targeting this protein
How approved and investigational drugs engage this protein — mechanism and action type, direct vs complex targeting, and how broadly each acts across other targets. A drug-first view (the section above groups the approved ones disease-first); direct binders with few recorded targets are listed first.
Voltage-gated potassium channel blocker
Indicated for Lambert-Eaton Myasthenic Syndrome
ChEMBL mechanism, action type, target identity and approved indications. Open Targets clinical status.
Translational evidence
Why this target matters therapeutically, strongest evidence first. Disease associations are gene-level (via the gene that encodes this protein) and open into the full confidence synthesis; the development universe, tractability and safety annotations are target-level, from Open Targets.
Strongest disease associations · via encoding gene KCNA5
Gene-level evidence surfaced through the gene KCNA5that encodes this protein — not a direct protein–disease relationship. Ranked by Forefront's causal-directness weighting, so genetically- and clinically-evidenced diseases lead over ones that merely share the literature.
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The evidence agreement range shows how closely the independent evidence families agree — it is not a statistical confidence interval, and nothing here is fitted to outcome data. Derived from Open Targets evidence types under Forefront weighting; the per-type scores above show the calculation.
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Drug development
8 compounds recorded · 7 approved · 1 in clinical development
View all recorded compounds (8)Hide
Open Targets known-drugs universe. Drug name and highest clinical stage only — the disease relationship is NOT read from this slice (it carries trial-context noise); approved indications come from the canonical graph above.
Tractability
Small molecules — Strong
Antibodies — Emerging
Protein degraders — Emerging
View underlying tractability evidence (8)Hide
Raw Open Targets tractability assessment buckets, by modality.
Clinical trials
Trials of drugs that target this protein — reached indirectly through those drugs, so a trial listed here studies the drug, not the protein. Ranked by active status, then clinical phase and recency, and spread across the targeting drugs.
View all trials (26)Hide
ClinicalTrials.gov via the drug-target graph.
What's happening now
Recent therapeutic activity around this target — regulatory actions, clinical trials and safety signals for 2 drugs that target this protein, plus publications where such a drug is a genuine subject. Every item is reached indirectly through the drug, not the protein itself; incidental mentions (a paper that merely measures a drug) and press items are excluded.
- Supplemental approval
Supplemental approval: DALFAMPRIDINE (ANDA210158)
- Label change
Label change: DALFAMPRIDINE (ANDA210158)
- Label change
Label change: DALFAMPRIDINE (ANDA210158)
- Label change
Label change: DALFAMPRIDINE (ANDA210158)
- Regulatory approval
Approval: DALFAMPRIDINE (ANDA210158)
- Regulatory approval
Approval: Firdapse (previously Zenas) (EMA)
Objective event titles are shown unmodified; the event kind and significance line are derived from structured fields. Forefront AttentionEvent stream aggregating Europe PMC Regulatory filings ClinicalTrials.gov.