Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Subscribe

Logo for

J. Biol. Chem. 278 (27): 24247-24250

© 2003 by The American Society for Biochemistry and Molecular Biology, Inc.


ACCELERATED PUBLICATIONS

Intracellular Coupling via Limiting Calmodulin*

Quang-Kim Tran, D. J. Black, and Anthony Persechini {ddagger}

Division of Molecular Biology & Biochemistry, School of Biological Sciences, University of Missouri, Kansas City, Missouri 64110-2499

Abstract: Measurements of cellular Ca2+-calmodulin concentrations have suggested that competition for limiting calmodulin may couple calmodulin-dependent activities. Here we have directly tested this hypothesis. We have found that in endothelial cells the amount of calmodulin bound to nitric-oxide synthase and the catalytic activity of the enzyme both are increased ~3-fold upon changes in the phosphorylation status of the enzyme. Quantitative immunoblotting indicates that the synthase can bind up to 25% of the total cellular calmodulin. Consistent with this, simultaneous determinations of the free Ca2+ and Ca2+-calmodulin concentrations in these cells performed using indo-1 and a fluorescent calmodulin biosensor (Kd = 2 nM) indicate that increased binding of calmodulin to the synthase is associated with substantial reductions in the Ca2+-calmodulin concentrations produced and an increase in the [Ca2+]50 for formation of the calmodulin-biosensor complex. The physiological significance of these effects is confirmed by a corresponding 40% reduction in calmodulin-dependent plasma membrane Ca2+ pump activity. An identical reduction in pump activity is produced by expression of a high affinity (Kd = 0.3 nM) calmodulin biosensor, and treatment to increase calmodulin binding to the synthase then has no further effect. This suggests that the observed reduction in pump activity is due specifically to reduced calmodulin availability. Increases in synthase activity thus appear to be coupled to decreases in the activities of other calmodulin targets through reductions in the size of a limiting pool of available calmodulin. This exemplifies what is likely to be a ubiquitous mechanism for coupling among diverse calmodulin-dependent activities.


Received for publication April 18, 2003. Revision received May 8, 2003.

* This work was supported by National Institutes of Health Grant DK 53863 (to A. P.). The costs of publication of this article were defrayed in part by the payment of page charges. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. Section 1734 solely to indicate this fact.

{ddagger} To whom correspondence should be addressed: Division of Molecular Biology & Biochemistry, School of Biological Sciences, University of Missouri-Kansas City, Rm. 412, Biological Sciences Bldg., 5007 Rockhill Rd., Kansas City, MO 64110-2499. Tel.: 816-235-5972; Fax: 816-235-5595; E-mail: persechinia{at}umkc.edu.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Signaling through Myosin Light Chain Kinase in Smooth Muscles.
N. Gao, J. Huang, W. He, M. Zhu, K. E. Kamm, and J. T. Stull (2013)
J. Biol. Chem. 288, 7596-7605
   Abstract »    Full Text »    PDF »
In vivo assessment of artery smooth muscle [Ca2+]i and MLCK activation in FRET-based biosensor mice.
J. Zhang, L. Chen, H. Raina, M. P. Blaustein, and W. G. Wier (2010)
Am J Physiol Heart Circ Physiol 299, H946-H956
   Abstract »    Full Text »    PDF »
Neurogranin enhances synaptic strength through its interaction with calmodulin.
L. Zhong, T. Cherry, C. E. Bies, M. A. Florence, and N. Z. Gerges (2009)
EMBO J. 28, 3027-3039
   Abstract »    Full Text »    PDF »
Differential Integration of Ca2+-Calmodulin Signal in Intact Ventricular Myocytes at Low and High Affinity Ca2+-Calmodulin Targets.
Q. Song, J. J. Saucerman, J. Bossuyt, and D. M. Bers (2008)
J. Biol. Chem. 283, 31531-31540
   Abstract »    Full Text »    PDF »
Calmodulin binding to M-type K+ channels assayed by TIRF/FRET in living cells.
M. Bal, O. Zaika, P. Martin, and M. S. Shapiro (2008)
J. Physiol. 586, 2307-2320
   Abstract »    Full Text »    PDF »
Calmodulin regulates the trafficking of KCNQ2 potassium channels.
A. Etxeberria, P. Aivar, J. A. Rodriguez-Alfaro, A. Alaimo, P. Villace, J. C. Gomez-Posada, P. Areso, and A. Villarroel (2008)
FASEB J 22, 1135-1143
   Abstract »    Full Text »    PDF »
A Novel Calmodulin-Ca2+ Target Recognition Activates the Bcl-2 Regulator FKBP38.
F. Edlich, M. Maestre-Martinez, F. Jarczowski, M. Weiwad, M.-C. Moutty, M. Malesevic, G. Jahreis, G. Fischer, and C. Lucke (2007)
J. Biol. Chem. 282, 36496-36504
   Abstract »    Full Text »    PDF »
Life history of eNOS: Partners and pathways.
D. M. Dudzinski and T. Michel (2007)
Cardiovasc Res 75, 247-260
   Abstract »    Full Text »    PDF »
Role of the neurogranin concentrated in spines in the induction of long-term potentiation..
A. M. Zhabotinsky, R. N. Camp, I. R. Epstein, and J. E. Lisman (2006)
J. Neurosci. 26, 7337-7347
   Abstract »    Full Text »    PDF »
The Role of Calmodulin Recruitment in Ca2+ Stimulation of Adenylyl Cyclase Type 8.
R. E. Simpson, A. Ciruela, and D. M. F. Cooper (2006)
J. Biol. Chem. 281, 17379-17389
   Abstract »    Full Text »    PDF »
Functional link between TNF biosynthesis and CaM-dependent activation of inducible nitric oxide synthase in RAW 264.7 macrophages.
T. J. Weber, H. S. Smallwood, L. E. Kathmann, L. M. Markillie, T. C. Squier, and B. D. Thrall (2006)
Am J Physiol Cell Physiol 290, C1512-C1520
   Abstract »    Full Text »    PDF »
Structural Requirements for Differential Sensitivity of KCNQ K+ Channels to Modulation by Ca2+/Calmodulin.
N. Gamper, Y. Li, and M. S. Shapiro (2005)
Mol. Biol. Cell 16, 3538-3551
   Abstract »    Full Text »    PDF »
Modes of Caldesmon Binding to Actin: SITES OF CALDESMON CONTACT AND MODULATION OF INTERACTIONS BY PHOSPHORYLATION.
D. B. Foster, R. Huang, V. Hatch, R. Craig, P. Graceffa, W. Lehman, and C.- L. A. Wang (2004)
J. Biol. Chem. 279, 53387-53394
   Abstract »    Full Text »    PDF »
Cell-matrix interaction via CD44 is independently regulated by different metalloproteinases activated in response to extracellular Ca2+ influx and PKC activation.
O. Nagano, D. Murakami, D. Hartmann, B. de Strooper, P. Saftig, T. Iwatsubo, M. Nakajima, M. Shinohara, and H. Saya (2004)
J. Cell Biol. 165, 893-902
   Abstract »    Full Text »    PDF »
Real-time evaluation of myosin light chain kinase activation in smooth muscle tissues from a transgenic calmodulin-biosensor mouse.
E. Isotani, G. Zhi, K. S. Lau, J. Huang, Y. Mizuno, A. Persechini, R. Geguchadze, K. E. Kamm, and J. T. Stull (2004)
PNAS 101, 6279-6284
   Abstract »    Full Text »    PDF »
Myosin V: regulation by calcium, calmodulin, and the tail domain.
D. N. Krementsov, E. B. Krementsova, and K. M. Trybus (2004)
J. Cell Biol. 164, 877-886
   Abstract »    Full Text »    PDF »
Calmodulin phosphorylation and modulation of endothelial nitric oxide synthase catalysis.
D. M. Greif, D. B. Sacks, and T. Michel (2004)
PNAS 101, 1165-1170
   Abstract »    Full Text »    PDF »

To Advertise     Find Products


Science Signaling. ISSN 1937-9145 (online), 1945-0877 (print). Pre-2008: Science's STKE. ISSN 1525-8882