Pflügers Archiv

, Volume 450, Issue 1, pp 34–44 | Cite as

Regulation of the voltage-gated potassium channel KCNQ4 in the auditory pathway

Cell and Molecular Physiology


The potassium channel KCNQ4, expressed in the mammalian cochlea, has been associated tentatively with an outer hair cell (OHC) potassium current, IK,n, a current distinguished by an activation curve shifted to exceptionally negative potentials. Using CHO cells as a mammalian expression system, we have examined the properties of KCNQ4 channels under different phosphorylation conditions. The expressed current showed the typical KCNQ4 voltage-dependence, with a voltage for half-maximal activation (V1/2) of −25 mV, and was blocked almost completely by 200 µM linopirdine. Application of 8-bromo-cAMP or the catalytic sub-unit of PKA shifted V1/2 by approximately −10 and −20 mV, respectively. Co-expression of KCNQ4 and prestin, the OHC motor protein, altered the voltage activation by a further −15 mV. Currents recorded with less than 1 nM Ca2+ in the pipette ran down slowly (12% over 5 min). Buffering the pipette Ca2+ to 100 nM increased the run-down rate sevenfold. Exogenous PKA in the pipette prevented the effect of elevated [Ca2+]i on run-down. Inhibition of the calcium binding proteins calmodulin or calcineurin by W-7 or cyclosporin A, respectively, also prevented the calcium-dependent rapid run-down. We suggest that KCNQ4 phosphorylation via PKA and coupling to a complex that may include prestin can lead to the negative activation and the negative resting potential found in adult OHCs.


Cochlea Hair cells Potassium channel Phosphorylation Prestin Calcium activated binding proteins 



We thank A. Tinker for the gift of the KCNQ4 clone and advice, DA. Brown for providing the KCNQ2 and KCNQ3 clones, B. Fakler for the rat prestin clone and M. Stocker for the KCNA1 clone. We thank H. Dorricott and R. Louvel for experimental assistance and J.E. Gale and D.J. Jagger for helpful discussion and critical review of the manuscript. This work was supported by the Wellcome Trust.


  1. 1.
    Adler HJ, Belyantseva IA, Merritt RC Jr, Frolenkov GI, Dougherty GW, Kachar B (2003) Expression of prestin, a membrane motor protein, in the mammalian auditory and vestibular periphery. Hear Res 184:27–40CrossRefGoogle Scholar
  2. 2.
    Allen V, Swigart P, Cheung R, Cockcroft S, Katan M (1997) Regulation of inositol lipid-specific phospholipase cδ by changes in Ca2+ ion concentrations. Biochem J 327:545–552Google Scholar
  3. 3.
    Amberg GC, Koh SD, Perrino BA, Hatton WJ, Sanders KM (2001) Regulation of A-type potassium channels in murine colonic myocytes by phosphatase activity. Am J Physiol 281:C2020–C2028Google Scholar
  4. 4.
    Barbara JG, Takeda K (1995) Voltage-dependent currents and modulation of calcium channel expression in zona fasciculata cells from rat adrenal gland. J Physiol (Lond) 488:609–622Google Scholar
  5. 5.
    Chen JW, Eatock RA (2000) Major potassium conductance in type I hair cells from rat semicircular canals: characterization and modulation by nitric oxide. J Neurophysiol 84:139–151Google Scholar
  6. 6.
    Coucke PJ, Van Hauwe P, Kelley PM, Kunst H, Schatteman I, Van Velzen D, Meyers J, Ensink RJ, Verstreken M, Declau F, Marres H, Kastury K, Bhasin S, McGuirt WT, Smith RJ, Cremers CW, Van de Heyning P, Willems PJ, Smith SD, Van Camp G (1999) Mutations in the KCNQ4 gene are responsible for autosomal dominant deafness in four DFNA2 families. Hum Mol Genet 8:1321–1328CrossRefGoogle Scholar
  7. 7.
    Czech MP (2000) PIP2 and PIP3: complex roles at the cell surface. Cell 100:603–606CrossRefGoogle Scholar
  8. 8.
    Erickson MG, Alseikhan BA, Peterson BZ, Yue DT (2001) Preassociation of calmodulin with voltage-gated Ca2+ channels revealed by FRET in single living cells. Neuron 31:973–985CrossRefGoogle Scholar
  9. 9.
    Fanger CM, Ghanshani S, Logsdon NJ, Rauer H, Kalman K, Zhou J, Beckingham K, Chandy KG, Cahalan MD, Aiyar J (1999) Calmodulin mediates calcium-dependent activation of the intermediate conductance KCa channel, IKCa1. J Biol Chem 274:5746–5754CrossRefPubMedGoogle Scholar
  10. 10.
    Frolenkov GI, Mammano F, Belyantseva IA, Coling D, Kachar B (2000) Two distinct Ca2+-dependent signaling pathways regulate the motor output of cochlear outer hair cells. J Neurosci 20:5940–5948Google Scholar
  11. 11.
    Gale JE, Ashmore JF (1997) The outer hair cell motor in membrane patches. Pflugers Arch 434:267–271CrossRefGoogle Scholar
  12. 12.
    Gamper N, Shapiro MS (2003) Calmodulin mediates Ca2+-dependent modulation of M-type K+ channels. J Gen Physiol 122:17–31CrossRefGoogle Scholar
  13. 13.
    Gamper N, Stockand JD, Shapiro MS (2003) Sub-unit specific modulation of KCNQ potassium channels by Src tyrosine kinase. J Neurosci 23:84–95Google Scholar
  14. 14.
    Genesca L, Aubareda A, Fuentes JJ, Estivill X, De La Luna S, Perez-Riba M (2003) Phosphorylation of calcipressin 1 increases its ability to inhibit calcineurin and decreases calcipressin half-life. Biochem J 374:567–575CrossRefGoogle Scholar
  15. 15.
    Grissmer S, Nguyen AN, Aiyar J, Hanson DC, Mather RJ, Gutman GA, Karmilowicz MJ, Auperin DD, Chandy KG (1994) Pharmacological characterization of five cloned voltage-gated K+ channels, types Kv1.1, 1.2, 1.3, 1.5, and 3.1, stably expressed in mammalian cell lines. Mol Pharmacol 45:1227–1234PubMedGoogle Scholar
  16. 16.
    Housley GD, Ashmore JF (1991) Direct measurement of the action of acetylcholine on isolated outer hair cells of the guinea pig cochlea. Proc R Soc Lond B Biol Sci 244:161–167Google Scholar
  17. 17.
    Housley GD, Ashmore JF (1992) Ionic currents of outer hair cells isolated from the guinea-pig cochlea. J Physiol (Lond) 448:73–98Google Scholar
  18. 18.
    Jagger DJ, Ashmore JF (1999) Regulation of ionic currents by protein kinase A and intracellular calcium in outer hair cells isolated from the guinea-pig cochlea. Pflugers Arch 437:409–416CrossRefGoogle Scholar
  19. 19.
    Kharkovets T, Hardelin JP, Safieddine S, Schweizer M, El-Amraoui A, Petit C, Jentsch TJ (2000) KCNQ4, a K+ channel mutated in a form of dominant deafness, is expressed in the inner ear and the central auditory pathway. Proc Natl Acad Sci USA 97:4333–4338CrossRefGoogle Scholar
  20. 20.
    Kubisch C, Schroeder BC, Friedrich T, Lutjohann B, El-Amraoui A, Marlin S, Petit C, Jentsch TJ (1999) KCNQ4, a novel potassium channel expressed in sensory outer hair cells, is mutated in dominant deafness. Cell 96:437–446CrossRefPubMedGoogle Scholar
  21. 21.
    Kumagami H, Beitz E, Wild K, Zenner HP, Ruppersberg JP, Schultz JE (1999) Expression pattern of adenylyl cyclase isoforms in the inner ear of the rat by RT-PCR and immunochemical localization of calcineurin in the organ of Corti. Hear Res 132:69–75CrossRefGoogle Scholar
  22. 22.
    Lerche C, Scherer CR, Seebohm G, Derst C, Wei AD, Busch AE, Steinmeyer K (2000) Molecular cloning and functional expression of KCNQ5, a potassium channel sub-unit that may contribute to neuronal M-current diversity. J Biol Chem 275:22395–22400CrossRefGoogle Scholar
  23. 23.
    Marcotti W, Kros CJ (1999) Developmental expression of the potassium current IK,n contributes to maturation of mouse outer hair cells. J Physiol (Lond) 520:653–660Google Scholar
  24. 24.
    Marcotti W, Johnson SL, Holley MC, Kros CJ (2003) Developmental changes in the expression of potassium currents of embryonic, neonatal and mature mouse inner hair cells. J Physiol (Lond) 548:383–400Google Scholar
  25. 25.
    Marx SO, Kurokawa J, Reiken S, Motoike H, D’Armiento J, Marks AR, Kass RS (2002) Requirement of a macromolecular signalling complex for beta adrenergic receptor modulation of the KCNQ1-KCNE1 potassium channel. Science 295:496–499CrossRefGoogle Scholar
  26. 26.
    Neyroud N, Tesson F, Denjoy I, Leibovici M, Donger C, Barhanin J, Faure S, Gary F, Coumel P, Petit C, Schwartz K, Guicheney P (1997) A novel mutation in the potassium channel gene KVLQT1 causes the Jervell and Lange-Nielsen cardioauditory syndrome. Nat Genet 15:186–189CrossRefPubMedGoogle Scholar
  27. 27.
    Oliver D, Knipper M, Derst C, Fakler B (2003) Resting potential and submembrane calcium concentration of inner hair cells in the isolated mouse cochlea are set by KCNQ-type potassium channels. J Neurosci 23:2141–2149Google Scholar
  28. 28.
    Peterson BZ, DeMaria CD, Adelman JP, Yue DT (1999) Calmodulin is the Ca2+ sensor for Ca2+-dependent inactivation of L-type calcium channels. Neuron 22:549–558CrossRefGoogle Scholar
  29. 29.
    Rusnak F, Mertz P (2000) Calcineurin: form and function. Physiol Rev 80:1483–1521Google Scholar
  30. 30.
    Saimi Y, Kung C (2002) Calmodulin as an ion channel subunit. Annu Rev Physiol 64:289–311CrossRefGoogle Scholar
  31. 31.
    Schonherr R, Lober K, Heinemann SH (2000) Inhibition of human ether a go-go potassium channels by Ca2+/calmodulin. EMBO J 19:3263–3271CrossRefGoogle Scholar
  32. 32.
    Schroder RL, Jespersen T, Christophersen P, Strobaek D, Jensen BS, Olesen SP (2001) KCNQ4 channel activation by BMS-204352 and retigabine. Neuropharmacology 40:888–898CrossRefGoogle Scholar
  33. 33.
    Schroeder BC, Kubisch C, Stein V, Jentsch TJ (1998) Moderate loss of function of cyclic-AMP-modulated KCNQ2/KCNQ3 K+ channels causes epilepsy. Nature 396:687–690CrossRefGoogle Scholar
  34. 34.
    Selyanko AA, Hadley JK, Wood IC, Abogadie FC, Jentsch TJ, Brown DA (2000) Inhibition of KCNQ1–4 potassium channels expressed in mammalian cells via muscarinic acetylcholine receptors. J Physiol (Lond) 522:349–355Google Scholar
  35. 35.
    Shin DW, Pan Z, Bandyopadhyay A, Bhat MB, Kim do H, Ma J (2002) Ca2+-dependent interaction between FKBP12 and calcineurin regulates activity of the Ca2+ release channel in skeletal muscle. Biophys J 83:2539–2549Google Scholar
  36. 36.
    Sogaard R, Ljungstrom T, Pedersen KA, Olesen SP, Jensen BS (2001) KCNQ4 channels expressed in mammalian cells: functional characteristics and pharmacology. Am J Physiol 280:C859–C866Google Scholar
  37. 37.
    Takuma T, Ichida T (1994) Evidence for the involvement of protein phosphorylation in cyclic AMP-mediated amylase exocytosis from parotid acinar cells. FEBS Lett 340:29–33CrossRefGoogle Scholar
  38. 38.
    Thornhill WB, Wu MB, Jiang X, Wu X, Morgan PT, Margiotta JF (1996) Expression of Kv1.1 delayed rectifier potassium channels in Lec mutant Chinese hamster ovary cell lines reveals a role for sialidation in channel function. J Biol Chem 271:19093–19098CrossRefGoogle Scholar
  39. 39.
    Wang HS, Pan Z, Shi W, Brown BS, Wymore RS, Cohen IS, Dixon JE, McKinnon D (1998) KCNQ2 and KCNQ3 potassium channel sub-units: molecular correlates of the M-channel. Science 282:1890–189CrossRefPubMedGoogle Scholar
  40. 40.
    Weiss TF (1996) Cellular biophysics: electrical properties. Vol. 2. MIT Press, Cambridge, pp 464–467Google Scholar
  41. 41.
    Wen H, Levitan IB (2002) Calmodulin is an auxiliary subunit of KCNQ2/3 potassium channels. J Neurosci 22:7991–8001Google Scholar
  42. 42.
    Xia XM, Fakler B, Rivard A, Wayman G, Johnson-Pais T, Keen JE, Ishii T, Hirschberg B, Bond CT, Lutsenko S, Maylie J, Adelman JP (1998) Mechanism of calcium gating in small-conductance calcium-activated potassium channels. Nature 395:503–507CrossRefPubMedGoogle Scholar
  43. 43.
    Yang WP, Levesque PC, Little WA, Conder ML, Ramakrishnan P, Neubauer MG, Blanar MA (1998) Functional expression of two KvLQT1-related potassium channels responsible for an inherited idiopathic epilepsy. J Biol Chem 273:19419–19423CrossRefGoogle Scholar
  44. 44.
    Yus-Najera E, Santana-Castro I, Villarroel A (2002) The identification and characterization of a noncontinuous calmodulin-binding site in noninactivating voltage-dependent KCNQ potassium channels. J Biol Chem 277:28545–28553CrossRefGoogle Scholar
  45. 45.
    Zamponi GW (2003) Calmodulin lobotomized: novel insights into calcium regulation of voltage-gated calcium channels. Neuron 39:879–881CrossRefGoogle Scholar
  46. 46.
    Zhang H, Craciun LC, Mirshahi T, Rohacs T, Lopes CM, Jin T, Logothetis DE (2003) PIP2 activates KCNQ channels, and its hydrolysis underlies receptor-mediated inhibition of M currents. Neuron 37:963–975CrossRefGoogle Scholar
  47. 47.
    Zheng J, Shen W, He DZ, Long KB, Madison LD, Dallos P (2000) Prestin is the motor protein of cochlear outer hair cells. Nature 405:130–133CrossRefGoogle Scholar

Copyright information

© Springer-Verlag  2005

Authors and Affiliations

  1. 1.Department of Physiology and Centre for Auditory ResearchUniversity College LondonLondonUK

Personalised recommendations