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. 1994 Jan 18;91(2):624–628. doi: 10.1073/pnas.91.2.624

Molecular basis of cardiac potassium channel stimulation by protein kinase A.

X Y Huang 1, A D Morielli 1, E G Peralta 1
PMCID: PMC43001  PMID: 8290574

Abstract

Cardiac beta-adrenergic receptors accelerate heart rate by modulating ionic currents through a pathway involving cyclic AMP-dependent protein kinase A (PKA). Previous studies have focused on the regulation of Ca2+ channels by PKA; however, due to the heterogeneity of K+ channels expressed within the heart, little is known about the mechanism by which PKA modulates individual K+ channels. Here we report that PKA strongly enhanced the activity of a cloned delayed rectifier K+ channel that is normally expressed in cardiac atria. This effect required a single PKA consensus phosphorylation site located near the amino terminus of the channel protein. Furthermore, patch clamp analysis revealed that PKA phosphorylation increased the open time that single channels spend in higher conductance states. These studies provide evidence that hormonal modulation of a cardiac K+ channel involves direct phosphorylation by PKA.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Ashby C. D., Walsh D. A. Characterization of the interaction of a protein inhibitor with adenosine 3',5'-monophosphate-dependent protein kinases. I. Interaction with the catalytic subunit of the protein kinase. J Biol Chem. 1972 Oct 25;247(20):6637–6642. [PubMed] [Google Scholar]
  2. Bean B. P., Nowycky M. C., Tsien R. W. Beta-adrenergic modulation of calcium channels in frog ventricular heart cells. 1984 Jan 26-Feb 1Nature. 307(5949):371–375. doi: 10.1038/307371a0. [DOI] [PubMed] [Google Scholar]
  3. Cachelin A. B., de Peyer J. E., Kokubun S., Reuter H. Ca2+ channel modulation by 8-bromocyclic AMP in cultured heart cells. Nature. 1983 Aug 4;304(5925):462–464. doi: 10.1038/304462a0. [DOI] [PubMed] [Google Scholar]
  4. Dohlman H. G., Thorner J., Caron M. G., Lefkowitz R. J. Model systems for the study of seven-transmembrane-segment receptors. Annu Rev Biochem. 1991;60:653–688. doi: 10.1146/annurev.bi.60.070191.003253. [DOI] [PubMed] [Google Scholar]
  5. Fischmeister R., Shrier A. Interactive effects of isoprenaline, forskolin and acetylcholine on Ca2+ current in frog ventricular myocytes. J Physiol. 1989 Oct;417:213–239. doi: 10.1113/jphysiol.1989.sp017798. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Gilman A. G. G proteins: transducers of receptor-generated signals. Annu Rev Biochem. 1987;56:615–649. doi: 10.1146/annurev.bi.56.070187.003151. [DOI] [PubMed] [Google Scholar]
  7. Hartzell H. C., Fischmeister R. Opposite effects of cyclic GMP and cyclic AMP on Ca2+ current in single heart cells. Nature. 1986 Sep 18;323(6085):273–275. doi: 10.1038/323273a0. [DOI] [PubMed] [Google Scholar]
  8. Hartzell H. C., Simmons M. A. Comparison of effects of acetylcholine on calcium and potassium currents in frog atrium and ventricle. J Physiol. 1987 Aug;389:411–422. doi: 10.1113/jphysiol.1987.sp016663. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Hoshi T., Zagotta W. N., Aldrich R. W. Biophysical and molecular mechanisms of Shaker potassium channel inactivation. Science. 1990 Oct 26;250(4980):533–538. doi: 10.1126/science.2122519. [DOI] [PubMed] [Google Scholar]
  10. Kennelly P. J., Krebs E. G. Consensus sequences as substrate specificity determinants for protein kinases and protein phosphatases. J Biol Chem. 1991 Aug 25;266(24):15555–15558. [PubMed] [Google Scholar]
  11. Kobilka B. K., Dixon R. A., Frielle T., Dohlman H. G., Bolanowski M. A., Sigal I. S., Yang-Feng T. L., Francke U., Caron M. G., Lefkowitz R. J. cDNA for the human beta 2-adrenergic receptor: a protein with multiple membrane-spanning domains and encoded by a gene whose chromosomal location is shared with that of the receptor for platelet-derived growth factor. Proc Natl Acad Sci U S A. 1987 Jan;84(1):46–50. doi: 10.1073/pnas.84.1.46. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Lechleiter J., Hellmiss R., Duerson K., Ennulat D., David N., Clapham D., Peralta E. Distinct sequence elements control the specificity of G protein activation by muscarinic acetylcholine receptor subtypes. EMBO J. 1990 Dec;9(13):4381–4390. doi: 10.1002/j.1460-2075.1990.tb07888.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Li M., West J. W., Lai Y., Scheuer T., Catterall W. A. Functional modulation of brain sodium channels by cAMP-dependent phosphorylation. Neuron. 1992 Jun;8(6):1151–1159. doi: 10.1016/0896-6273(92)90135-z. [DOI] [PubMed] [Google Scholar]
  14. McKinnon D. Isolation of a cDNA clone coding for a putative second potassium channel indicates the existence of a gene family. J Biol Chem. 1989 May 15;264(14):8230–8236. [PubMed] [Google Scholar]
  15. Melton D. A., Krieg P. A., Rebagliati M. R., Maniatis T., Zinn K., Green M. R. Efficient in vitro synthesis of biologically active RNA and RNA hybridization probes from plasmids containing a bacteriophage SP6 promoter. Nucleic Acids Res. 1984 Sep 25;12(18):7035–7056. doi: 10.1093/nar/12.18.7035. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Nunoki K., Florio V., Catterall W. A. Activation of purified calcium channels by stoichiometric protein phosphorylation. Proc Natl Acad Sci U S A. 1989 Sep;86(17):6816–6820. doi: 10.1073/pnas.86.17.6816. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Patlak J. B. Sodium channel subconductance levels measured with a new variance-mean analysis. J Gen Physiol. 1988 Oct;92(4):413–430. doi: 10.1085/jgp.92.4.413. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Paulmichl M., Nasmith P., Hellmiss R., Reed K., Boyle W. A., Nerbonne J. M., Peralta E. G., Clapham D. E. Cloning and expression of a rat cardiac delayed rectifier potassium channel. Proc Natl Acad Sci U S A. 1991 Sep 1;88(17):7892–7895. doi: 10.1073/pnas.88.17.7892. [DOI] [PMC free article] [PubMed] [Google Scholar]
  19. Perozo E., Bezanilla F. Phosphorylation affects voltage gating of the delayed rectifier K+ channel by electrostatic interactions. Neuron. 1990 Nov;5(5):685–690. doi: 10.1016/0896-6273(90)90222-2. [DOI] [PubMed] [Google Scholar]
  20. Stansfeld C. E., Marsh S. J., Gibb A. J., Brown D. A. Identification of M-channels in outside-out patches excised from sympathetic ganglion cells. Neuron. 1993 Apr;10(4):639–654. doi: 10.1016/0896-6273(93)90166-o. [DOI] [PubMed] [Google Scholar]
  21. Trautwein W., Hescheler J. Regulation of cardiac L-type calcium current by phosphorylation and G proteins. Annu Rev Physiol. 1990;52:257–274. doi: 10.1146/annurev.ph.52.030190.001353. [DOI] [PubMed] [Google Scholar]
  22. Walsh K. B., Begenisich T. B., Kass R. S. Beta-adrenergic modulation in the heart. Independent regulation of K and Ca channels. Pflugers Arch. 1988 Feb;411(2):232–234. doi: 10.1007/BF00582323. [DOI] [PubMed] [Google Scholar]
  23. Walsh K. B., Kass R. S. Regulation of a heart potassium channel by protein kinase A and C. Science. 1988 Oct 7;242(4875):67–69. doi: 10.1126/science.2845575. [DOI] [PubMed] [Google Scholar]
  24. Yokoyama S., Imoto K., Kawamura T., Higashida H., Iwabe N., Miyata T., Numa S. Potassium channels from NG108-15 neuroblastoma-glioma hybrid cells. Primary structure and functional expression from cDNAs. FEBS Lett. 1989 Dec 18;259(1):37–42. doi: 10.1016/0014-5793(89)81488-7. [DOI] [PubMed] [Google Scholar]

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