KV3.3 channels
| Channel name | KV3.31,2,3,4 |
| Description | Voltage-gated A-type potassium channel2 |
| Other names | hKv3.3, mKv3.3,1 RKShIIID,3 Kv3.3b4 |
| Molecular information | Human: 757aa, NM_004977, chr. 19q13.3-4,1,2,3 KCNC3, GeneID: 3748, PMID: 17403291 |
| Mouse: 679aa, NM_008422, chr. 7 | |
| Rat: 770aa, NM_053997, chr. 1q22 | |
| Associated subunits | None |
| Functional assays | Electrophysiology |
| Current | A-type |
| Conductance | Not established |
| Ion selectivity | K+ |
| Activation | Va = 7 mV; ka = 6 mV2 |
| Inactivation | τh ∼ 200 ms (40 mV)2 |
| Activators | None |
| Gating inhibitors | None |
| Blockers | Tetraethyammonium (0.14 mM),2 4-aminopyridine (1.2 mM)2; blocked by hypoxia5 |
| Radioligands | None |
| Channel distribution | Brain, Purkinje cells, central nervous system motoneurons; auditory brainstem12; electrosensory, cerebellar neurons, central auditory nuclei6,7,8; mesenteric artery9; lens and corneal epithelium10 |
| Physiological functions | Not established |
| Mutations and pathophysiology | See “Comments” |
| Pharmacological significance | Not established |
| Comments | Alcohol hypersensitivity, ataxia, increased locomotion and myoclonus occur in mice lacking KV3.3 and KV3.111; mammalian Shaw-related family |
aa, amino acids; chr., chromosome.
↵1. Ghanshani S, Pak M, McPherson JD, Strong M, Dethlefs B, Wasmuth JJ, Salkoff L, Gutman GA, and Chandy KG (1992) Genomic organization, nucleotide sequence, and cellular distribution of a Shaw-related potassium channel gene, Kv3.3, and mapping of Kv3.3 and Kv3.4 to human chromosomes 19 and 1. Genomics 12:190-196
↵2. Vega-Saenzde Miera E, Moreno H, Fruhling D, Kentros C, and Rudy B (1992) Cloning of ShIII (Shaw-like) cDNAs encoding a novel high-voltage-activating, TEA-sensitive, type-A K+ channel. Proc R Soc Lond B Biol Sci 248:9-18
↵3. Haas M, Ward DC, Lee J, Roses AD, Clarke V, D'Eustachio P, Lau D, Vega-Saenz de Miera E, and Rudy B (1993) Localization of Shaw-related K+ channel genes on mouse and human chromosomes. Mamm Genome 4:711-715
↵4. Goldman-Wohl DS, Chan E, Baird D, and Heintz N (1994) Kv3.3b: a novel Shaw type potassium channel expressed in terminally differentiated cerebellar Purkinje cells and deep cerebellar nuclei. J Neurosci 14:511-522
↵5. Patel AJ and Honore E (2001) Molecular physiology of oxygen-sensitive potassium channels. Eur Respir J 18:221-227
↵6. Rashid AJ, Dunn RJ, and Turner RW (2001) A prominent soma-dendritic distribution of Kv3.3 K+ channels in electrosensory and cerebellar neurons. J Comp Neurol 441:234-247
↵7. Grigg JJ, Brew HM, and Tempel BL (2000) Differential expression of voltage-gated potassium channel genes in auditory nuclei of the mouse brainstem. Hear Res 140:77-90
↵8. Li W, Kaczmarek LK, and Perney TM (2001) Localization of two high-threshold potassium channel subunits in the rat central auditory system. J Comp Neurol 437:196-218
↵9. Xu C, Lu Y, Tang G, and Wang R (1999) Expression of voltage-dependent K+ channel genes in mesenteric artery smooth muscle cells. Am J Physiol 277:G1055-G1063
↵10. Rae JL and Shepard AR (2000) Kv3.3 potassium channels in lens epithelium and corneal endothelium. Exp Eye Res 70:339-348
↵11. Espinosa F, McMahon A, Chan E, Wang S, Ho CS, Heintz N, and Joho RH (2001) Alcohol hyper-sensitivity, increased locomotion, and spontaneous myoclonus in mice lacking the potassium channels Kv3.1 and Kv3.3. J Neurosci 21:6657-6665
↵12. Weiser M, Bueno E, Sekirnjak C, Martone ME, Baker H, Hillman D, Chen S, Thornhill W, Ellisman M, and Rudy B (1995) The potassium channel subunit KV3.1b is localized to somatic and axonal membranes of specific populations of CNS neurons. J Neurosci 15:4298-4314