Channel | KCa 5.1 |
Description | pH-sensitive large-conductance potassium channel |
Other names | Slo3, KCNMC1, Kcnma3 |
Molecular information | Human: BC028701 (coding sequence not defined), chr. 8p11.2,7 KCNU1 |
Mouse: 1112aa, NM_008432, chr. 8 | |
Rat: 1243aa, NM_031828, chr. 15p16 | |
Associated subunits | No β-subunits identified |
Functional Assays | Voltage- and patch-clamp |
Current | K+-selective (mouse Slo3) |
Conductance | 106pS with 160 mM symmetric K+ (mouse Slo3)2 |
Ion Selectivity | PK+/PNa+ = 5.0 (mouse Slo3)2 |
Activation | Gated by voltage and internal alkalization (half-maximal activation at pH 7.5)1,2,3,4,5,6 |
Inactivation | None |
Activators | None |
Blockers | TEA, 50% block by 49 mM2 |
Gating inhibitors | None |
Radioligands | None |
Channel distribution | Testis, spermatocytes2 |
Physiological functions | Not established |
Mutations and pathophysiology | Not established |
Pharmacological significance | Not established |
Comments | No published functional expression data for the human ortholog |
aa, amino acids; chr., chromosome; TEA, tetraethylammonium.
↵1. Moss BL and Magleby KL (2001) Gating and conductance properties of BK channels are modulated by the S9-S10 tail domain of the alpha subunitA study of mSlo1 and mSlo3 wild-type and chimeric channels J Gen Physiol 118:711-734
↵2. Schreiber M, Wei A, Yuan A, Gaut J, Saito M, and Salkoff L (1998) Slo3, a novel pH-sensitive K+ channel from mammalian spermatocytes. J Biol Chem 273:3509-3516
↵3. Schreiber M, Yuan A, and Salkoff L (1999) Transplantable sites confer calcium sensitivity to BK channels. Nat Neurosci 2:416-421
↵4. Shi J and Cui J (2001) Intracellular Mg2+ enhances the function of BK-type Ca2+-activated K+ channels. J Gen Physiol 118:589-606
↵5. Shi J, Krishnamoorthy G, Yang Y, Hu L, Chaturvedi N, Harilal D, Qin J, and Cui J (2002) Mechanism of magnesium activation of calcium-activated potassium channels. Nature (Lond) 418:876-880
↵6. Xia XM, Zhang X, and Lingle CJ (2004) Ligand-dependent activation of Slo family channels is defined by interchangeable cytosolic domains. J Neurosci 24:5585-5591
↵7. GenBank accession no. AP000074