Names & Taxonomy
- Uniprot ID:
- P22459
- Entry Name:
- KCNA4_HUMAN
- Status:
- reviewed
- Protein Names:
- Potassium voltage-gated channel subfamily A member 4 (HPCN2) (Voltage-gated K(+) channel HuKII) (Voltage-gated potassium channel HBK4) (Voltage-gated potassium channel HK1) (Voltage-gated potassium channel subunit Kv1.4)
- Gene Names:
- KCNA4 KCNA4L
- Gene Names Primary:
- KCNA4
- Organism:
- Homo sapiens (Human)
Structure
- Length:
- 653
- Sequence:
- MEVAMVSAESSGCNSHMPYGYAAQARARERERLAHSRAAAAAAVAAATAAVEGSGGSGGGSHHHHQSRGACTSHDPQSSRGSRRRRRQRSEKKKAHYRQSSFPHCSDLMPSGSEEKILRELSEEEEDEEEEEEEEEEGRFYYSEDDHGDECSYTDLLPQDEGGGGYSSVRYSDCCERVVINVSGLRFETQMKTLAQFPETLLGDPEKRTQYFDPLRNEYFFDRNRPSFDAILYYYQSGGRLKRPVNVPFDIFTEEVKFYQLGEEALLKFREDEGFVREEEDRALPENEFKKQIWLLFEYPESSSPARGIAIVSVLVILISIVIFCLETLPEFRDDRDLVMALSAGGHGGLLNDTSAPHLENSGHTIFNDPFFIVETVCIVWFSFEFVVRCFACPSQALFFKNIMNIIDIVSILPYFITLGTDLAQQQGGGNGQQQQAMSFAILRIIRLVRVFRIFKLSRHSKGLQILGHTLRASMRELGLLIFFLFIGVILFSSAVYFAEADEPTTHFQSIPDAFWWAVVTMTTVGYGDMKPITVGGKIVGSLCAIAGVLTIALPVPVIVSNFNYFYHRETENEEQTQLTQNAVSCPYLPSNLLKKFRSSTSSSLGDKSEYLEMEEGVKESLCAKEEKCQGKGDDSETDKNNCSNAKAVETDV
- Proteomes:
- UP000005640
Subcellular location
- Subcellular Location:
- Cell membrane
- Intramembrane:
- INTRAMEM 512 523 Helical; Name=Pore helix.
Function
- Function:
- 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 (PubMed:19912772, PubMed:8495559). 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:8495559). Channel properties are modulated by cytoplasmic beta subunits that regulate the subcellular location of the alpha subunits and promote rapid inactivation. In vivo, membranes probably contain a mixture of heteromeric potassium channel complexes, making it difficult to assign currents observed in intact tissues to any particular potassium channel family member. Homotetrameric KCNA4 forms a potassium channel that opens in response to membrane depolarization, followed by rapid spontaneous channel closure (PubMed:19912772, PubMed:8495559). Likewise, a heterotetrameric channel formed by KCNA1 and KCNA4 shows rapid inactivation (PubMed:17156368).
- Enzyme Regulation:
- ENZYME REGULATION: Inhibited by 4-aminopyridine (4-AP), but not by tetraethylammonium (TEA) and charybdotoxin (CTX).
- Cross Reference Drug Bank:
- DB06637
- Gene Ontology Go:
- axon
integral component of membrane
integral component of plasma membrane
plasma membrane
voltage-gated potassium channel complex
potassium ion binding
voltage-gated potassium channel activity
potassium ion transmembrane transport
potassium ion transport
protein homooligomerization
synaptic transmission - Gene Ontology Biological Process:
- potassium ion transmembrane transport
potassium ion transport
protein homooligomerization
synaptic transmission - Gene Ontology Molecular Function:
- potassium ion binding
voltage-gated potassium channel activity - Gene Ontology Cellular Component:
- axon
integral component of membrane
integral component of plasma membrane
plasma membrane
voltage-gated potassium channel complex - Keywords:
- Cell membrane
Cell projection
Complete proteome
Glycoprotein
Ion channel
Ion transport
Membrane
Phosphoprotein
Potassium
Potassium channel
Potassium transport
Reference proteome
Transmembrane
Transmembrane helix
Transport
Voltage-gated channel - Interacts With:
- Q62936; P78352; P31016