KV10.2 channels
| Channel name | KV10.2 |
| Description | Outward-rectifying, noninactivating voltage-dependent K+ currents3,4,5 |
| Other names | eag21,2,3,4,5 |
| Molecular information | Human: 987aa, NM_139318 (transcript variant 1), chr. 14q23.1, KCNH5 (see “Comments”), GeneID: 27133, PMID: 97384732 |
| Mouse: 988aa, NM_172805, chr. 12 | |
| Rat: 988aa, NM_133610, chr. 6q24 | |
| Associated subunits | Hyperkinetic (Hk),6 CaM, Slob, KCR1 (potassium channel regulator) |
| Functional assays | Voltage-clamp |
| Current | Outward-rectifying |
| Conductance | Not established |
| Ion selectivity | K+ |
| Activation | Activates at —100 mV (rat)3 |
| Inactivation | Noninactivating |
| Activators | None |
| Gating inhibitors | None |
| Blockers | Quinidine (152 μM),5 intracellular calcium (nanomolar)4 |
| Radioligands | None |
| Channel distribution | Brain (layer IV of the cerebral cortex; thalamus, inferior colliculus, olfactory bulb, and certain brainstem nuclei)3,4 |
| Physiological functions | Not established |
| Mutations and pathophysiology | Not established |
| Pharmacological significance | Not established |
| Comments | This channel has a GFG (rather than the common GYG) potassium channel signature sequence, a PAS domain in the distal part of the cytosolic N terminus, a cNBD domain in the proximal portion of the C terminus, a C-terminal assembly domain (CAD), a CaM-binding domain, a bNLS domain in the C terminus, and a C-terminal domain is required for assembly7; the TCC domain at the C-terminal end of Kv10 and Kv11 confers specificity for multimer formation, allowing Kv10.1/Kv10.2 heteromerization and Kv11 homomerization but not Kv10.x/Kv11.x heteromerization8; this C-terminal TCC domain has been identified in many other channels, and mutations of the TCC have been found to be linked to genetic channelopathies |
aa, amino acids; chr., chromosome; CaM, calmodulin; TCC, tetramerizing coiled-coiled.
↵1. Shi W, Wang HS, Pan Z, Wymore RS, Cohen IS, McKinnon D, and Dixon JE (1998) Cloning of a mammalian elk potassium channel gene and EAG mRNA distribution in rat sympathetic ganglia. J Physiol 511:675-682
↵2. Occhiodoro T, Bernheim L, Liu JH, Bijlenga P, Sinnreich M, Bader CR, and Fischer-Lougheed J (1998) Cloning of a human ether-à-go-go potassium channel expressed in myoblasts at the onset of fusion. FEBS Lett 434:177-182
↵3. Saganich MJ, Vega-Saenz de Miera E, Nadal MS, Baker H, Coetzee WA, and Rudy B (1999) Cloning of components of a novel subthreshold-activating K+ channel with a unique pattern of expression in the cerebral cortex. J Neurosci 19:10789-10802
↵4. Ludwig J, Weseloh R, Karschin C, Liu Q, Netzer R, Engeland B, Stansfeld C, and Pongs O (2000) Cloning and functional expression of rat eag2, a new member of the ether-à-go-go family of potassium channels and comparison of its distribution with that of eag1. Mol Cell Neurosci 16:59-70
↵5. Schonherr R, Gessner G, Lober K, and Heinemann SH (2002) Functional distinction of human EAG1 and EAG2 potassium channels. FEBS Lett 514:204-208
↵6. Wilson GF, Wang Z, Chouinard SW, Griffith LC, and Ganetzky B (1998) Interaction of the K channel β subunit, Hyperkinetic, with eag family members. J Biol Chem 273:6389-6394
↵7. Ludwig J, Owen D, and Pongs O (1997) Carboxy-terminal domain mediates assembly of the voltage-gated rat ether-à-go-go potassium channel. EMBO J 16:6337-6345
↵8. Jenke M, Sanchez A, Monje F, Stuhmer W, Weseloh RM, and Pardo LA (2003) C-terminal domains implicated in the functional surface expression of potassium channels. EMBO J 22:395-403