KV2.2 channels
| Channel name | KV2.21,2,3 |
| Description | Voltage-gated potassium channel, delayed rectifier |
| Other names | CDRK |
| Molecular information | Human: 911 aa, NM_004770, chr. 8q13.2, KCNB2, GeneID: 9312, PMID: 961227215 |
| Mouse: 758 aa, XM_136482 (predicted), chr. 1 | |
| Rat: 802 aa, NM_054000, chr. 5q11 | |
| Associated subunits | Mouse KVβ4 associates with KV2.2 and enhances expression level, KV8.1, KV9, KChaP4,5,6,7 |
| Functional assays | Voltage-clamp |
| Current | None determined |
| Conductance | 15pS8 |
| Ion selectivity | K+-selective |
| Activation | Voltage |
| Inactivation | Noninactivating |
| Activators | None |
| Gating inhibitors | None |
| Blockers | Quinine (13.7 μM), tetraethyammonium (2.6 mM), 4-aminopyridine (1.5 mM), phencyclidine (μM)8,9 |
| Radioligands | None |
| Channel distribution | Brain [olfactory bulb (granule cell layer > olfactory tubercle) > cortex > hippocampus > cerebellum; hypothalamus], ventricle, tongue, sympathetic neurons, gastrointestinal smooth muscle, mesenteric artery smooth muscle1,2,3,10,11,12,13,14 |
| Physiological functions | Maintaining membrane potential, modulating electrical excitability in neurons |
| Mutations and pathophysiology | Not established |
| Pharmacological significance | Not established |
| Comments | The angiotensin II type 1 receptor mediates inhibition of KV2.2 in brainstem and hypothalamic neurons12; mammalian Shab-related family |
aa, amino acids; chr., chromosome.
↵1. Hwang PM, Glatt CE, Bredt DS, Yellen G, and Snyder SH. (1992). A novel K+ channel with unique localizations in mammalian brain: molecular cloning and characterization. Neuron 8:473-481
↵2. Hwang PM, Fotuhi M, Bredt DS, Cunningham AM, and Snyder SH (1993) Contrasting immunohistochemical localizations in rat brain of two novel K+ channels of the Shab subfamily. J Neurosci 13:1569-1576
↵3. Hwang PM, Cunningham AM, Peng YW, and Snyder SH (1993) CDRK and DRK1 K+ channels have contrasting localizations in sensory systems. Neuroscience 55:613-620
↵4. Fink M, Duprat F, Lesage F, Heurteaux C, Romey G, Barhanin J, and Lazdunski M (1996) A new K+ channel β subunit to specifically enhance Kv2.2 (CDRK) expression. J Biol Chem 271:26341-26348
↵5. Salinas M, de Weille J, Guillemare E, Lazdunski M, and Hugnot JP (1997) Modes of regulation of Shab K+ channel activity by the Kv8.1 subunit. J Biol Chem 272:8774-8780
↵6. Salinas M, Duprat F, Heurteaux C, Hugnot JP, and Lazdunski M (1997) New modulatory α subunits for mammalian Shab K+ channels. J Biol Chem 272:24371-24379
↵7. Wible BA, Yang Q, Kuryshev YA, Accili EA, and Brown AM (1998) Cloning and expression of a novel K+ channel regulatory protein, KChAP. J Biol Chem 273:11745-11751
↵8. Schmalz F, Kinsella J, Koh SD, Vogalis F, Schneider A, Flynn ER, Kenyon JL, and Horowitz B (1998) Molecular identification of a component of delayed rectifier current in gastrointestinal smooth muscles. Am J Physiol 274:G901-G911
↵9. Frey BW, Lynch FT, Kinsella JM, Horowitz B, Sanders KM, and Carl A (2000) Blocking of cloned and native delayed rectifier K channels from visceral smooth muscles by phencyclidine. Neurogastroenterol Motil 12:509-516
↵10. Maletic-Savatic M, Lenn NJ, and Trimmer JS (1995) Differential spatiotemporal expression of K+ channel polypeptides in rat hippocampal neurons developing in situ and in vitro. J Neurosci 15:3840-3851
↵11. Dixon JE and McKinnon D (1996) Potassium channel mRNA expression in prevertebral and para-vertebral sympathetic neurons. Eur J Neurosci 8:183-191
↵12. Gelband CH, Warth JD, Mason HS, Zhu M, Moore JM, Kenyon JL, Horowitz B, and Sumners C (1999) Angiotensin II type 1 receptor-mediated inhibition of K+ channel subunit Kv2.2 in brain stem and hypothalamic neurons. Circ Res 84:352-359
↵13. 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
↵14. Lim ST, Antonucci DE, Scannevin RH, and Trimmer JS (2000) A novel targeting signal for proximal clustering of the Kv2.1 K+ channel in hippocampal neurons. Neuron 25:385-397
↵15. Schmalz F, Kinsella J, Koh SD, Vogalis F, Schneider A, Flynn ER, Kenyon JL, and Horowitz B (1998) Molecular identification of a component of delayed rectifier current in gastrointestinal smooth muscles. Am J Physiol 274:G901-G911