Guard Cells Possess a Calcium-Dependent Protein Kinase That Phosphorylates the KAT1 Potassium Channel¹

Jiaxu Li, Yuh-Ru Julie Lee, and Sarah M. Assmann^*

Department of Biology and Plant Physiology Program, The Pennsylvania State University, University Park, Pennsylvania 16802

Increasing evidence suggests that changes in cytosolic Ca²⁺ levels and phosphorylation play important roles in the regulation of stomatal aperture and as ion transporters of guard cells. However, protein kinases responsible for Ca²⁺ signaling in guard cells remain to be identified. Using biochemical approaches, we have identified a Ca²⁺-dependent protein kinase with a calmodulin-like domain (CDPK) in guard cell protoplasts of Vicia faba. Both autophosphorylation and catalytic activity of CDPK are Ca²⁺ dependent. CDPK exhibits a Ca²⁺-induced electrophoretic mobility shift and its Ca²⁺-dependent catalytic activity can be inhibited by the calmodulin antagonists trifluoperazine and N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide. Antibodies to soybean CDPK cross-react with CDPK. Micromolar Ca²⁺ concentrations stimulate phosphorylation of several proteins from guard cells; cyclosporin A, a specific inhibitor of the Ca²⁺-dependent protein phosphatase calcineurin enhances the Ca²⁺-dependent phosphorylation of several soluble proteins. CDPK from guard cells phosphorylates the K⁺ channel KAT1 protein in a Ca²⁺-dependent manner. These results suggest that CDPK may be an important component of Ca²⁺ signaling in guard cells.

Plant Physiol. (1998) 116: 785-795
Copyright Clearance Center:   0032-0889/98/116/0785/11
© 1998 American Society of Plant Physiologists

This article has been cited by other articles:

				C. Sirichandra, A. Wasilewska, F. Vlad, C. Valon, and J. Leung The guard cell as a single-cell model towards understanding drought tolerance and abscisic acid action J. Exp. Bot., April 1, 2009; 60(5): 1439 - 1463. [Abstract] [Full Text] [PDF]

				S.-Y. Zhu, X.-C. Yu, X.-J. Wang, R. Zhao, Y. Li, R.-C. Fan, Y. Shang, S.-Y. Du, X.-F. Wang, F.-Q. Wu, et al. Two Calcium-Dependent Protein Kinases, CPK4 and CPK11, Regulate Abscisic Acid Signal Transduction in Arabidopsis PLANT CELL, October 1, 2007; 19(10): 3019 - 3036. [Abstract] [Full Text] [PDF]

				H. Marten, K. R. Konrad, P. Dietrich, M. R. G. Roelfsema, and R. Hedrich Ca2+-Dependent and -Independent Abscisic Acid Activation of Plasma Membrane Anion Channels in Guard Cells of Nicotiana tabacum Plant Physiology, January 1, 2007; 143(1): 28 - 37. [Abstract] [Full Text] [PDF]

				L. Yu, D. Becker, H. Levi, M. Moshelion, R. Hedrich, I. Lotan, A. Moran, U. Pick, L. Naveh, Y. Libal, et al. Phosphorylation of SPICK2, an AKT2 channel homologue from Samanea motor cells J. Exp. Bot., November 1, 2006; 57(14): 3583 - 3594. [Abstract] [Full Text] [PDF]

				M. L. Lanteri, G. C. Pagnussat, and L. Lamattina Calcium and calcium-dependent protein kinases are involved in nitric oxide- and auxin-induced adventitious root formation in cucumber J. Exp. Bot., March 1, 2006; 57(6): 1341 - 1351. [Abstract] [Full Text] [PDF]

				E. Michard, B. Lacombe, F. Poree, B. Mueller-Roeber, H. Sentenac, J.-B. Thibaud, and I. Dreyer A Unique Voltage Sensor Sensitizes the Potassium Channel AKT2 to Phosphoregulation J. Gen. Physiol., November 28, 2005; 126(6): 605 - 617. [Abstract] [Full Text] [PDF]

				T. Wolf, D. R. Guinot, R. Hedrich, P. Dietrich, and I. Marten Nucleotides and Mg2+ Ions Differentially Regulate K+ Channels and Non-Selective Cation Channels Present in Cells Forming the Stomatal Complex Plant Cell Physiol., October 1, 2005; 46(10): 1682 - 1689. [Abstract] [Full Text] [PDF]

				N. Ivashikina, R. Deeken, S. Fischer, P. Ache, and R. Hedrich AKT2/3 Subunits Render Guard Cell K+ Channels Ca2+ Sensitive J. Gen. Physiol., April 25, 2005; 125(5): 483 - 492. [Abstract] [Full Text] [PDF]

				E. W. Chehab, O. R. Patharkar, A. D. Hegeman, T. Taybi, and J. C. Cushman Autophosphorylation and Subcellular Localization Dynamics of a Salt- and Water Deficit-Induced Calcium-Dependent Protein Kinase from Ice Plant Plant Physiology, July 1, 2004; 135(3): 1430 - 1446. [Abstract] [Full Text] [PDF]

				I. Cherel Regulation of K+ channel activities in plants: from physiological to molecular aspects J. Exp. Bot., February 1, 2004; 55(396): 337 - 351. [Abstract] [Full Text] [PDF]

				D. Takezawa Characterization of a Novel Plant PP2C-like Protein Ser/Thr Phosphatase as a Calmodulin-binding Protein J. Biol. Chem., September 26, 2003; 278(39): 38076 - 38083. [Abstract] [Full Text] [PDF]

				C. Dammann, A. Ichida, B. Hong, S. M. Romanowsky, E. M. Hrabak, A. C. Harmon, B. G. Pickard, and J. F. Harper Subcellular Targeting of Nine Calcium-Dependent Protein Kinase Isoforms from Arabidopsis Plant Physiology, August 1, 2003; 132(4): 1840 - 1848. [Abstract] [Full Text] [PDF]

				N. V. Fedoroff Cross-Talk in Abscisic Acid Signaling Sci. Signal., July 9, 2002; 2002(140): re10 - re10. [Abstract] [Full Text] [PDF]

				S.-H. Cheng, M. R. Willmann, H.-C. Chen, and J. Sheen Calcium Signaling through Protein Kinases. The Arabidopsis Calcium-Dependent Protein Kinase Gene Family Plant Physiology, June 1, 2002; 129(2): 469 - 485. [Abstract] [Full Text] [PDF]

				B.-C. Yoo, J.-Y. Lee, and W. J. Lucas Analysis of the Complexity of Protein Kinases within the Phloem Sieve Tube System. CHARACTERIZATION OF CUCURBITA MAXIMA CALMODULIN-LIKE DOMAIN PROTEIN KINASE 1 J. Biol. Chem., May 3, 2002; 277(18): 15325 - 15332. [Abstract] [Full Text] [PDF]

				I. Cherel, E. Michard, N. Platet, K. Mouline, C. Alcon, H. Sentenac, and J.-B. Thibaud Physical and Functional Interaction of the Arabidopsis K+ Channel AKT2 and Phosphatase AtPP2CA PLANT CELL, May 1, 2002; 14(5): 1133 - 1146. [Abstract] [Full Text] [PDF]

				D. Sanders, J. Pelloux, C. Brownlee, and J. F. Harper Calcium at the Crossroads of Signaling PLANT CELL, May 1, 2002; 14(90001): S401 - 417. [Full Text] [PDF]

				L. Yu, M. Moshelion, and N. Moran Extracellular Protons Inhibit the Activity of Inward- Rectifying Potassium Channels in the Motor Cells of Samanea saman Pulvini Plant Physiology, November 1, 2001; 127(3): 1310 - 1322. [Abstract] [Full Text] [PDF]

				G. J. Allen and J. I. Schroeder Combining Genetics and Cell Biology to Crack the Code of Plant Cell Calcium Signaling Sci. Signal., October 2, 2001; 2001(102): re13 - re13. [Abstract] [Full Text] [PDF]

				H. Osawa and H. Matsumoto Possible Involvement of Protein Phosphorylation in Aluminum-Responsive Malate Efflux from Wheat Root Apex Plant Physiology, May 1, 2001; 126(1): 411 - 420. [Abstract] [Full Text]

				J.-U. Hwang and Y. Lee Abscisic Acid-Induced Actin Reorganization in Guard Cells of Dayflower Is Mediated by Cytosolic Calcium Levels and by Protein Kinase and Protein Phosphatase Activities Plant Physiology, April 1, 2001; 125(4): 2120 - 2128. [Abstract] [Full Text]

				F. Sutton, S. S. Paul, X.-Q. Wang, and S. M. Assmann Distinct Abscisic Acid Signaling Pathways for Modulation of Guard Cell versus Mesophyll Cell Potassium Channels Revealed by Expression Studies in Xenopus laevis Oocytes Plant Physiology, September 1, 2000; 124(1): 223 - 230. [Abstract] [Full Text]

				I. C. Mori, N. Uozumi, and S. Muto Phosphorylation of the Inward-Rectifying Potassium Channel KAT1 by ABR Kinase in Vicia Guard Cells Plant Cell Physiol., July 1, 2000; 41(7): 850 - 856. [Abstract] [Full Text] [PDF]

				I. Hwang, H. Sze, and J. F. Harper A calcium-dependent protein kinase can inhibit a calmodulin-stimulated Ca2+ pump (ACA2) located in the endoplasmic reticulum of Arabidopsis PNAS, May 23, 2000; 97(11): 6224 - 6229. [Abstract] [Full Text] [PDF]

				T. Romeis, P. Piedras, and J. D. G. Jones Resistance Gene-Dependent Activation of a Calcium-Dependent Protein Kinase in the Plant Defense Response PLANT CELL, May 1, 2000; 12(5): 803 - 816. [Abstract] [Full Text]

				J. Li, X. Wang, M. B. Watson, and S. M. Assmann Regulation of Abscisic Acid-Induced Stomatal Closure and Anion Channels by Guard Cell AAPK Kinase Science, January 14, 2000; 287(5451): 300 - 303. [Abstract] [Full Text]

				T. Jacob, S. Ritchie, S. M. Assmann, and S. Gilroy Abscisic acid signal transduction in guard cells is mediated by phospholipase D activity PNAS, October 12, 1999; 96(21): 12192 - 12197. [Abstract] [Full Text] [PDF]

				T. Taybi and J. C. Cushman Signaling Events Leading to Crassulacean Acid Metabolism Induction in the Common Ice Plant Plant Physiology, October 1, 1999; 121(2): 545 - 556. [Abstract] [Full Text]

				D. Sanders, C. Brownlee, and J. F. Harper Communicating with Calcium PLANT CELL, April 1, 1999; 11(4): 691 - 706. [Full Text]

				S. M. Assmann and K.-i. Shimazaki The Multisensory Guard Cell. Stomatal Responses to Blue Light and Abscisic Acid Plant Physiology, March 1, 1999; 119(3): 809 - 816. [Full Text]

				G. Anthony Pearson and S. Howard Brawley A Model for Signal Transduction during Gamete Release in the Fucoid Alga Pelvetia compressa Plant Physiology, September 1, 1998; 118(1): 305 - 313. [Abstract] [Full Text]

				G. Pilot, B. Lacombe, F. Gaymard, I. Cherel, J. Boucherez, J.-B. Thibaud, and H. Sentenac Guard Cell Inward K+ Channel Activity in Arabidopsis Involves Expression of the Twin Channel Subunits KAT1 and KAT2 J. Biol. Chem., January 26, 2001; 276(5): 3215 - 3221. [Abstract] [Full Text] [PDF]

				H. Kieschnick, T. Wakefield, C. A. Narducci, and C. Beckers Toxoplasma gondii Attachment to Host Cells Is Regulated by a Calmodulin-like Domain Protein Kinase J. Biol. Chem., April 6, 2001; 276(15): 12369 - 12377. [Abstract] [Full Text] [PDF]

				S. X. Lu and E. M. Hrabak An Arabidopsis Calcium-Dependent Protein Kinase Is Associated with the Endoplasmic Reticulum Plant Physiology, March 1, 2002; 128(3): 1008 - 1021. [Abstract] [Full Text] [PDF]