KCNA1

Highest pathogenic variant AF is 6.84149e-7

Gene type

protein_coding

Transcript type

protein_coding

Transcript

ENST00000382545

Coding exons

1

Length

21457

Individuals with no LoFs

125741

Homozygous LoFs

0

Heterozygous LoFs

7

Defined

125748

p

0.0000278

Function

FUNCTION: Voltage-gated potassium channel that mediates transmembrane potassium transport in excitable membranes, primarily in the brain and the central nervous system, but also in the kidney (PubMed:19903818). Contributes to the regulation of the membrane potential and nerve signaling, and prevents neuronal hyperexcitability (PubMed:17156368). 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). Can form functional homotetrameric channels and heterotetrameric channels that contain variable proportions of KCNA1, KCNA2, KCNA4, KCNA5, KCNA6, KCNA7, and possibly other family members as well; channel properties depend on the type of alpha subunits that are part of the channel (PubMed:12077175, PubMed:17156368). Channel properties are modulated by cytoplasmic beta subunits that regulate the subcellular location of the alpha subunits and promote rapid inactivation of delayed rectifier potassium channels (PubMed:12077175, PubMed:17156368). 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 KCNA1 forms a delayed-rectifier potassium channel that opens in response to membrane depolarization, followed by slow spontaneous channel closure (PubMed:19912772, PubMed:19968958, PubMed:19307729, PubMed:19903818). In contrast, a heterotetrameric channel formed by KCNA1 and KCNA4 shows rapid inactivation (PubMed:17156368). Regulates neuronal excitability in hippocampus, especially in mossy fibers and medial perforant path axons, preventing neuronal hyperexcitability. Response to toxins that are selective for KCNA1, respectively for KCNA2, suggests that heteromeric potassium channels composed of both KCNA1 and KCNA2 play a role in pacemaking and regulate the output of deep cerebellar nuclear neurons (By similarity). May function as down- stream effector for G protein-coupled receptors and inhibit GABAergic inputs to basolateral amygdala neurons (By similarity). May contribute to the regulation of neurotransmitter release, such as gamma-aminobutyric acid (GABA) release (By similarity). Plays a role in regulating the generation of action potentials and preventing hyperexcitability in myelinated axons of the vagus nerve, and thereby contributes to the regulation of heart contraction (By similarity). Required for normal neuromuscular responses (PubMed:11026449, PubMed:17136396). Regulates the frequency of neuronal action potential firing in response to mechanical stimuli, and plays a role in the perception of pain caused by mechanical stimuli, but does not play a role in the perception of pain due to heat stimuli (By similarity). Required for normal responses to auditory stimuli and precise location of sound sources, but not for sound perception (By similarity). The use of toxins that block specific channels suggest that it contributes to the regulation of the axonal release of the neurotransmitter dopamine (By similarity). Required for normal postnatal brain development and normal proliferation of neuronal precursor cells in the brain (By similarity). Plays a role in the reabsorption of Mg(2+) in the distal convoluted tubules in the kidney and in magnesium ion homeostasis, probably via its effect on the membrane potential (PubMed:23903368, PubMed:19307729). {ECO:0000250|UniProtKB:P10499, ECO:0000269|PubMed:11026449, ECO:0000269|PubMed:12077175, ECO:0000269|PubMed:15837928, ECO:0000269|PubMed:17136396, ECO:0000269|PubMed:17156368, ECO:0000269|PubMed:19307729, ECO:0000269|PubMed:19903818, ECO:0000269|PubMed:19912772, ECO:0000269|PubMed:19968958, ECO:0000269|PubMed:21106501, ECO:0000269|PubMed:23903368}.;

Disease

DISEASE: Episodic ataxia 1 (EA1) [MIM:160120]: An autosomal dominant disorder characterized by brief episodes of ataxia and dysarthria. Neurological examination during and between the attacks demonstrates spontaneous, repetitive discharges in the distal musculature (myokymia) that arise from peripheral nerve. Nystagmus is absent. {ECO:0000269|PubMed:10355668, ECO:0000269|PubMed:11013453, ECO:0000269|PubMed:11026449, ECO:0000269|PubMed:12077175, ECO:0000269|PubMed:15532032, ECO:0000269|PubMed:17156368, ECO:0000269|PubMed:7842011, ECO:0000269|PubMed:8541859, ECO:0000269|PubMed:8845167, ECO:0000269|PubMed:8871592, ECO:0000269|PubMed:9600245}. Note=The disease is caused by mutations affecting the gene represented in this entry.; DISEASE: Myokymia isolated 1 (MK1) [MIM:160120]: A condition characterized by spontaneous involuntary contraction of muscle fiber groups that can be observed as vermiform movement of the overlying skin. Electromyography typically shows continuous motor unit activity with spontaneous oligo- and multiplet-discharges of high intraburst frequency (myokymic discharges). Isolated spontaneous muscle twitches occur in many persons and have no grave significance. {ECO:0000269|PubMed:11026449, ECO:0000269|PubMed:17136396, ECO:0000269|PubMed:19307729, ECO:0000269|PubMed:19903818}. Note=The disease is caused by mutations affecting the gene represented in this entry.;