Physical and Functional Interaction of the Arabidopsis K(+) Channel AKT2 and Phosphatase AtPP2CA

Overview

Journal Plant Cell

Publisher Oxford University Press

Specialties Biology
Cell Biology

Date 2002 May 30

PMID 12034902

Citations 72

Authors

Isabelle Cherel

Erwan Michard

Nadine Platet

Karine Mouline

Carine Alcon

Herve Sentenac

Jean-Baptiste Thibaud

Affiliations

Soon will be listed here.

Abstract

The AKT2 K(+) channel is endowed with unique functional properties, being the only weak inward rectifier characterized to date in Arabidopsis. The gene is expressed widely, mainly in the phloem but also at lower levels in leaf epiderm, mesophyll, and guard cells. The AKT2 mRNA level is upregulated by abscisic acid. By screening a two-hybrid cDNA library, we isolated a protein phosphatase 2C (AtPP2CA) involved in abscisic acid signaling as a putative partner of AKT2. We further confirmed the interaction by in vitro binding studies. The expression of AtPP2CA (beta-glucuronidase reporter gene) displayed a pattern largely overlapping that of AKT2 and was upregulated by abscisic acid. Coexpression of AtPP2CA with AKT2 in COS cells and Xenopus laevis oocytes was found to induce both an inhibition of the AKT2 current and an increase of the channel inward rectification. Site-directed mutagenesis and pharmacological analysis revealed that this functional interaction involves AtPP2CA phosphatase activity. Regulation of AKT2 activity by AtPP2CA in planta could allow the control of K(+) transport and membrane polarization during stress situations.

Citing Articles

Potassium extrusion by plant cells: evolution from an emergency valve to a driver of long-distance transport.

Hmidi D, Muraya F, Fizames C, Very A, Roelfsema M New Phytol. 2024; 245(1):69-87.

PMID: 39462778 PMC: 11617655. DOI: 10.1111/nph.20207.

Interactions between Brassinosteroids and Strigolactones in Alleviating Salt Stress in Maize.

Wang X, Qi X, Zhuang Z, Bian J, Li J, Chen J Int J Mol Sci. 2024; 25(19).

PMID: 39408841 PMC: 11477198. DOI: 10.3390/ijms251910505.

Research Progress on Plant Shaker K Channels.

Yuan G, Nong T, Hunpatin O, Shi C, Su X, Wang Q Plants (Basel). 2024; 13(10).

PMID: 38794493 PMC: 11125005. DOI: 10.3390/plants13101423.

Transcriptome Profiling Reveals Molecular Responses to Salt Stress in Common Vetch ( L.).

Sun Y, Zhao N, Sun H, Xu S, Lu Y, Xi H Plants (Basel). 2024; 13(5).

PMID: 38475559 PMC: 10935011. DOI: 10.3390/plants13050714.

Overdominant expression of related genes of ion homeostasis improves K content advantage in hybrid tobacco leaves.

Pi K, Luo W, Mo Z, Duan L, Ke Y, Wang P BMC Plant Biol. 2022; 22(1):335.

PMID: 35820807 PMC: 9277951. DOI: 10.1186/s12870-022-03719-1.

References

Hamill O, Marty A, Neher E, Sakmann B, Sigworth F . Improved patch-clamp techniques for high-resolution current recording from cells and cell-free membrane patches. Pflugers Arch. 1981; 391(2):85-100. DOI: 10.1007/BF00656997. View

Hoshi T . Regulation of voltage dependence of the KAT1 channel by intracellular factors. J Gen Physiol. 1995; 105(3):309-28. PMC: 2216946. DOI: 10.1085/jgp.105.3.309. View

Thiel G, Macrobbie E, Blatt M . Membrane transport in stomatal guard cells: the importance of voltage control. J Membr Biol. 1992; 126(1):1-18. DOI: 10.1007/BF00233456. View

Leonhardt N, Marin E, Vavasseur A, Forestier C . Evidence for the existence of a sulfonylurea-receptor-like protein in plants: modulation of stomatal movements and guard cell potassium channels by sulfonylureas and potassium channel openers. Proc Natl Acad Sci U S A. 1997; 94(25):14156-61. PMC: 28449. DOI: 10.1073/pnas.94.25.14156. View

Gietz D, St Jean A, Woods R, Schiestl R . Improved method for high efficiency transformation of intact yeast cells. Nucleic Acids Res. 1992; 20(6):1425. PMC: 312198. DOI: 10.1093/nar/20.6.1425. View

Merlot S, Gosti F, Guerrier D, Vavasseur A, Giraudat J . The ABI1 and ABI2 protein phosphatases 2C act in a negative feedback regulatory loop of the abscisic acid signalling pathway. Plant J. 2001; 25(3):295-303. DOI: 10.1046/j.1365-313x.2001.00965.x. View

Blatt M . Cellular signaling and volume control in stomatal movements in plants. Annu Rev Cell Dev Biol. 2000; 16:221-41. DOI: 10.1146/annurev.cellbio.16.1.221. View

McNicholas C, Wang W, Ho K, Hebert S, Giebisch G . Regulation of ROMK1 K+ channel activity involves phosphorylation processes. Proc Natl Acad Sci U S A. 1994; 91(17):8077-81. PMC: 44548. DOI: 10.1073/pnas.91.17.8077. View

Ache P, Becker D, Deeken R, Dreyer I, Weber H, Fromm J . VFK1, a Vicia faba K(+) channel involved in phloem unloading. Plant J. 2001; 27(6):571-80. View

10.

Mori I, Uozumi N, Muto S . Phosphorylation of the inward-rectifying potassium channel KAT1 by ABR kinase in Vicia guard cells. Plant Cell Physiol. 2000; 41(7):850-6. DOI: 10.1093/pcp/pcd003. View

11.

Li J, Lee Y, Assmann S . Guard cells possess a calcium-dependent protein kinase that phosphorylates the KAT1 potassium channel. Plant Physiol. 1998; 116(2):785-95. PMC: 35138. DOI: 10.1104/pp.116.2.785. View

12.

Deeken R, Sanders C, Ache P, Hedrich R . Developmental and light-dependent regulation of a phloem-localised K+ channel of Arabidopsis thaliana. Plant J. 2000; 23(2):285-90. DOI: 10.1046/j.1365-313x.2000.00791.x. View

13.

Nakamura R, McKendree Jr W, Hirsch R, Sedbrook J, Gaber R, Sussman M . Expression of an Arabidopsis potassium channel gene in guard cells. Plant Physiol. 1995; 109(2):371-4. PMC: 157599. DOI: 10.1104/pp.109.2.371. View

14.

Bockenhauer D, Zilberberg N, Goldstein S . KCNK2: reversible conversion of a hippocampal potassium leak into a voltage-dependent channel. Nat Neurosci. 2001; 4(5):486-91. DOI: 10.1038/87434. View

15.

Dreyer I, Michard E, Lacombe B, Thibaud J . A plant Shaker-like K+ channel switches between two distinct gating modes resulting in either inward-rectifying or "leak" current. FEBS Lett. 2001; 505(2):233-9. DOI: 10.1016/s0014-5793(01)02832-0. View

16.

Hirsch R, Lewis B, Spalding E, Sussman M . A role for the AKT1 potassium channel in plant nutrition. Science. 1998; 280(5365):918-21. DOI: 10.1126/science.280.5365.918. View

17.

Blatt M . K+ channels of stomatal guard cells. Characteristics of the inward rectifier and its control by pH. J Gen Physiol. 1992; 99(4):615-44. PMC: 2219207. DOI: 10.1085/jgp.99.4.615. View

18.

Maathuis F, Sanders D . Contrasting roles in ion transport of two K(+)-channel types in root cells of Arabidopsis thaliana. Planta. 1995; 197(3):456-64. DOI: 10.1007/BF00196667. View

19.

Cao Y, Ward J, Kelly W, Ichida A, Gaber R, ANDERSON J . Multiple genes, tissue specificity, and expression-dependent modulationcontribute to the functional diversity of potassium channels in Arabidopsis thaliana. Plant Physiol. 1995; 109(3):1093-106. PMC: 161413. DOI: 10.1104/pp.109.3.1093. View

20.

Armstrong F, Leung J, Grabov A, Brearley J, Giraudat J, Blatt M . Sensitivity to abscisic acid of guard-cell K+ channels is suppressed by abi1-1, a mutant Arabidopsis gene encoding a putative protein phosphatase. Proc Natl Acad Sci U S A. 1995; 92(21):9520-4. PMC: 40833. DOI: 10.1073/pnas.92.21.9520. View