Skip to main content
Proceedings of the National Academy of Sciences of the United States of America logoLink to Proceedings of the National Academy of Sciences of the United States of America
. 1993 Nov 1;90(21):10135–10139. doi: 10.1073/pnas.90.21.10135

Voltage-dependent potentiation of the activity of cardiac L-type calcium channel alpha 1 subunits due to phosphorylation by cAMP-dependent protein kinase.

A Sculptoreanu 1, E Rotman 1, M Takahashi 1, T Scheuer 1, W A Catterall 1
PMCID: PMC47728  PMID: 7694283

Abstract

Barium currents mediated by the alpha 1 subunit of the cardiac L-type Ca channel expressed in Chinese hamster ovary (CHO) cells were increased up to 10-fold during dialysis of the cell with the catalytic subunit of cAMP-dependent protein kinase. After partial activation by exogenous kinase, the activity of the alpha 1 subunit was also reversibly potentiated up to 3.5-fold by prepulses to voltages in the range of 0 to +150 mV. Potentiation at +48 mV developed with a biphasic time course with time constants of 131 ms and 8 s. Reversal at -60 mV was biphasic with half-times of 12 ms and 100 ms and was blocked in the presence of the phosphatase inhibitor okadaic acid. Both the increase in calcium-channel activity during dialysis with kinase and the voltage-dependent potentiation were accompanied by shifts in the voltage dependence of activation to more negative membrane potentials. The increases in Ba current due to protein phosphorylation and to the dihydropyridine Ca channel agonist Bay K8644 were approximately additive. The results show that the alpha 1 subunit of the cardiac L-type Ca channel is sufficient for substantial modulation of Ca-channel activity by cAMP-dependent protein kinase and for potentiation by state-dependent protein phosphorylation. Voltage-dependent potentiation of the activity of the alpha 1 subunit may contribute to the increase in contractile force in response to increased rate of stimulation, the positive staircase effect in heart muscle.

Full text

PDF
10135

Selected References

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

  1. Artalejo C. R., Rossie S., Perlman R. L., Fox A. P. Voltage-dependent phosphorylation may recruit Ca2+ current facilitation in chromaffin cells. Nature. 1992 Jul 2;358(6381):63–66. doi: 10.1038/358063a0. [DOI] [PubMed] [Google Scholar]
  2. Cohen P., Cohen P. T. Protein phosphatases come of age. J Biol Chem. 1989 Dec 25;264(36):21435–21438. [PubMed] [Google Scholar]
  3. Fabiato A., Fabiato F. Contractions induced by a calcium-triggered release of calcium from the sarcoplasmic reticulum of single skinned cardiac cells. J Physiol. 1975 Aug;249(3):469–495. doi: 10.1113/jphysiol.1975.sp011026. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Fedida D., Noble D., Spindler A. J. Mechanism of the use dependence of Ca2+ current in guinea-pig myocytes. J Physiol. 1988 Nov;405:461–475. doi: 10.1113/jphysiol.1988.sp017342. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Frace A. M., Méry P. F., Fischmeister R., Hartzell H. C. Rate-limiting steps in the beta-adrenergic stimulation of cardiac calcium current. J Gen Physiol. 1993 Mar;101(3):337–353. doi: 10.1085/jgp.101.3.337. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Hess P., Lansman J. B., Tsien R. W. Different modes of Ca channel gating behaviour favoured by dihydropyridine Ca agonists and antagonists. Nature. 1984 Oct 11;311(5986):538–544. doi: 10.1038/311538a0. [DOI] [PubMed] [Google Scholar]
  7. Kaczmarek L. K., Jennings K. R., Strumwasser F., Nairn A. C., Walter U., Wilson F. D., Greengard P. Microinjection of catalytic subunit of cyclic AMP-dependent protein kinase enhances calcium action potentials of bag cell neurons in cell culture. Proc Natl Acad Sci U S A. 1980 Dec;77(12):7487–7491. doi: 10.1073/pnas.77.12.7487. [DOI] [PMC free article] [PubMed] [Google Scholar]
  8. Lacerda A. E., Brown A. M. Nonmodal gating of cardiac calcium channels as revealed by dihydropyridines. J Gen Physiol. 1989 Jun;93(6):1243–1273. doi: 10.1085/jgp.93.6.1243. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Lee K. S. Potentiation of the calcium-channel currents of internally perfused mammalian heart cells by repetitive depolarization. Proc Natl Acad Sci U S A. 1987 Jun;84(11):3941–3945. doi: 10.1073/pnas.84.11.3941. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Mikami A., Imoto K., Tanabe T., Niidome T., Mori Y., Takeshima H., Narumiya S., Numa S. Primary structure and functional expression of the cardiac dihydropyridine-sensitive calcium channel. Nature. 1989 Jul 20;340(6230):230–233. doi: 10.1038/340230a0. [DOI] [PubMed] [Google Scholar]
  11. Noble S., Shimoni Y. Voltage-dependent potentiation of the slow inward current in frog atrium. J Physiol. 1981 Jan;310:77–95. doi: 10.1113/jphysiol.1981.sp013538. [DOI] [PMC free article] [PubMed] [Google Scholar]
  12. Pietrobon D., Hess P. Novel mechanism of voltage-dependent gating in L-type calcium channels. Nature. 1990 Aug 16;346(6285):651–655. doi: 10.1038/346651a0. [DOI] [PubMed] [Google Scholar]
  13. Reuter H. Calcium channel modulation by neurotransmitters, enzymes and drugs. Nature. 1983 Feb 17;301(5901):569–574. doi: 10.1038/301569a0. [DOI] [PubMed] [Google Scholar]
  14. Sculptoreanu A., Scheuer T., Catterall W. A. Voltage-dependent potentiation of L-type Ca2+ channels due to phosphorylation by cAMP-dependent protein kinase. Nature. 1993 Jul 15;364(6434):240–243. doi: 10.1038/364240a0. [DOI] [PubMed] [Google Scholar]
  15. Tiaho F., Nargeot J., Richard S. Voltage-dependent regulation of L-type cardiac Ca channels by isoproterenol. Pflugers Arch. 1991 Dec;419(6):596–602. doi: 10.1007/BF00370301. [DOI] [PubMed] [Google Scholar]
  16. 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]
  17. Tsien R. W., Bean B. P., Hess P., Lansman J. B., Nilius B., Nowycky M. C. Mechanisms of calcium channel modulation by beta-adrenergic agents and dihydropyridine calcium agonists. J Mol Cell Cardiol. 1986 Jul;18(7):691–710. doi: 10.1016/s0022-2828(86)80941-5. [DOI] [PubMed] [Google Scholar]
  18. Yoshida A., Takahashi M., Nishimura S., Takeshima H., Kokubun S. Cyclic AMP-dependent phosphorylation and regulation of the cardiac dihydropyridine-sensitive Ca channel. FEBS Lett. 1992 Sep 14;309(3):343–349. doi: 10.1016/0014-5793(92)80804-p. [DOI] [PubMed] [Google Scholar]
  19. Yue D. T., Herzig S., Marban E. Beta-adrenergic stimulation of calcium channels occurs by potentiation of high-activity gating modes. Proc Natl Acad Sci U S A. 1990 Jan;87(2):753–757. doi: 10.1073/pnas.87.2.753. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Zygmunt A. C., Maylie J. Stimulation-dependent facilitation of the high threshold calcium current in guinea-pig ventricular myocytes. J Physiol. 1990 Sep;428:653–671. doi: 10.1113/jphysiol.1990.sp018233. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Proceedings of the National Academy of Sciences of the United States of America are provided here courtesy of National Academy of Sciences

RESOURCES