Click here to close
Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly.
We suggest using a current version of Chrome,
FireFox, or Safari.
Proc Natl Acad Sci U S A
2012 Jun 26;10926:10593-8. doi: 10.1073/pnas.1116590109.
Show Gene links
Show Anatomy links
Reconstitution of abscisic acid activation of SLAC1 anion channel by CPK6 and OST1 kinases and branched ABI1 PP2C phosphatase action.
Brandt B, Brodsky DE, Xue S, Negi J, Iba K, Kangasjärvi J, Ghassemian M, Stephan AB, Hu H, Schroeder JI.
???displayArticle.abstract???
The plant hormone abscisic acid (ABA) is produced in response to abiotic stresses and mediates stomatal closure in response to drought via recently identified ABA receptors (pyrabactin resistance/regulatory component of ABA receptor; PYR/RCAR). SLAC1 encodes a central guard cell S-type anion channel that mediates ABA-induced stomatal closure. Coexpression of the calcium-dependent protein kinase 21 (CPK21), CPK23, or the Open Stomata 1 kinase (OST1) activates SLAC1 anion currents. However, reconstitution of ABA activation of any plant ion channel has not yet been attained. Whether the known core ABA signaling components are sufficient for ABA activation of SLAC1 anion channels or whether additional components are required remains unknown. The Ca(2+)-dependent protein kinase CPK6 is known to function in vivo in ABA-induced stomatal closure. Here we show that CPK6 robustly activates SLAC1-mediated currents and phosphorylates the SLAC1 N terminus. A phosphorylation site (S59) in SLAC1, crucial for CPK6 activation, was identified. The group A PP2Cs ABI1, ABI2, and PP2CA down-regulated CPK6-mediated SLAC1 activity in oocytes. Unexpectedly, ABI1 directly dephosphorylated the N terminus of SLAC1, indicating an alternate branched early ABA signaling core in which ABI1 targets SLAC1 directly (down-regulation). Furthermore, here we have successfully reconstituted ABA-induced activation of SLAC1 channels in oocytes using the ABA receptor pyrabactin resistant 1 (PYR1) and PP2C phosphatases with two alternate signaling cores including either CPK6 or OST1. Point mutations in ABI1 disrupting PYR1-ABI1 interaction abolished ABA signal transduction. Moreover, by addition of CPK6, a functional ABA signal transduction core from ABA receptors to ion channel activation was reconstituted without a SnRK2 kinase.
Allan,
Two Transduction Pathways Mediate Rapid Effects of Abscisic Acid in Commelina Guard Cells.
1994, Pubmed
Allan,
Two Transduction Pathways Mediate Rapid Effects of Abscisic Acid in Commelina Guard Cells.
1994,
Pubmed Allen,
Arabidopsis abi1-1 and abi2-1 phosphatase mutations reduce abscisic acid-induced cytoplasmic calcium rises in guard cells.
1999,
Pubmed Belin,
Identification of features regulating OST1 kinase activity and OST1 function in guard cells.
2006,
Pubmed Chen,
Homologue structure of the SLAC1 anion channel for closing stomata in leaves.
2010,
Pubmed
,
Xenbase Curran,
Calcium-dependent protein kinases from Arabidopsis show substrate specificity differences in an analysis of 103 substrates.
2011,
Pubmed Cutler,
Abscisic acid: emergence of a core signaling network.
2010,
Pubmed Franz,
Calcium-dependent protein kinase CPK21 functions in abiotic stress response in Arabidopsis thaliana.
2011,
Pubmed Fujii,
In vitro reconstitution of an abscisic acid signalling pathway.
2009,
Pubmed Geiger,
Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca2+ affinities.
2010,
Pubmed
,
Xenbase Geiger,
Stomatal closure by fast abscisic acid signaling is mediated by the guard cell anion channel SLAH3 and the receptor RCAR1.
2011,
Pubmed
,
Xenbase Geiger,
Activity of guard cell anion channel SLAC1 is controlled by drought-stress signaling kinase-phosphatase pair.
2009,
Pubmed
,
Xenbase Grabov,
Membrane voltage initiates Ca2+ waves and potentiates Ca2+ increases with abscisic acid in stomatal guard cells.
1998,
Pubmed Hashimoto,
Phosphorylation of calcineurin B-like (CBL) calcium sensor proteins by their CBL-interacting protein kinases (CIPKs) is required for full activity of CBL-CIPK complexes toward their target proteins.
2012,
Pubmed Hedrich,
Ca2+ and nucleotide dependent regulation of voltage dependent anion channels in the plasma membrane of guard cells.
1990,
Pubmed Hrabak,
The Arabidopsis CDPK-SnRK superfamily of protein kinases.
2003,
Pubmed Kuhn,
The protein phosphatase AtPP2CA negatively regulates abscisic acid signal transduction in Arabidopsis, and effects of abh1 on AtPP2CA mRNA.
2006,
Pubmed Lee,
A protein kinase-phosphatase pair interacts with an ion channel to regulate ABA signaling in plant guard cells.
2009,
Pubmed
,
Xenbase Leung,
Arabidopsis ABA response gene ABI1: features of a calcium-modulated protein phosphatase.
1994,
Pubmed Li,
Regulation of abscisic acid-induced stomatal closure and anion channels by guard cell AAPK kinase.
2000,
Pubmed Ma,
AtCPK23 functions in Arabidopsis responses to drought and salt stresses.
2007,
Pubmed Ma,
Regulators of PP2C phosphatase activity function as abscisic acid sensors.
2009,
Pubmed MacRobbie,
ABA activates multiple Ca(2+) fluxes in stomatal guard cells, triggering vacuolar K(+)(Rb(+)) release.
2000,
Pubmed Melcher,
A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors.
2009,
Pubmed Meyer,
A protein phosphatase 2C involved in ABA signal transduction in Arabidopsis thaliana.
1994,
Pubmed Miyazono,
Structural basis of abscisic acid signalling.
2009,
Pubmed Mori,
CDPKs CPK6 and CPK3 function in ABA regulation of guard cell S-type anion- and Ca(2+)-permeable channels and stomatal closure.
2006,
Pubmed Munemasa,
The Arabidopsis calcium-dependent protein kinase, CPK6, functions as a positive regulator of methyl jasmonate signaling in guard cells.
2011,
Pubmed Mustilli,
Arabidopsis OST1 protein kinase mediates the regulation of stomatal aperture by abscisic acid and acts upstream of reactive oxygen species production.
2002,
Pubmed Negi,
CO2 regulator SLAC1 and its homologues are essential for anion homeostasis in plant cells.
2008,
Pubmed Nishimura,
Structural mechanism of abscisic acid binding and signaling by dimeric PYR1.
2009,
Pubmed Nishimura,
PYR/PYL/RCAR family members are major in-vivo ABI1 protein phosphatase 2C-interacting proteins in Arabidopsis.
2010,
Pubmed Nour-Eldin,
Advancing uracil-excision based cloning towards an ideal technique for cloning PCR fragments.
2006,
Pubmed Park,
Abscisic acid inhibits type 2C protein phosphatases via the PYR/PYL family of START proteins.
2009,
Pubmed Pei,
Differential abscisic acid regulation of guard cell slow anion channels in Arabidopsis wild-type and abi1 and abi2 mutants.
1997,
Pubmed Santiago,
The abscisic acid receptor PYR1 in complex with abscisic acid.
2009,
Pubmed Santiago,
Modulation of drought resistance by the abscisic acid receptor PYL5 through inhibition of clade A PP2Cs.
2009,
Pubmed Schmidt,
Strong regulation of slow anion channels and abscisic acid signaling in guard cells by phosphorylation and dephosphorylation events.
1995,
Pubmed Schroeder,
Identification of High-Affinity Slow Anion Channel Blockers and Evidence for Stomatal Regulation by Slow Anion Channels in Guard Cells.
1993,
Pubmed Schwartz,
Role of Ca and EGTA on Stomatal Movements in Commelina communis L.
1985,
Pubmed Sheen,
Mutational analysis of protein phosphatase 2C involved in abscisic acid signal transduction in higher plants.
1998,
Pubmed Siegel,
Calcium elevation-dependent and attenuated resting calcium-dependent abscisic acid induction of stomatal closure and abscisic acid-induced enhancement of calcium sensitivities of S-type anion and inward-rectifying K channels in Arabidopsis guard cells.
2009,
Pubmed Szostkiewicz,
Closely related receptor complexes differ in their ABA selectivity and sensitivity.
2010,
Pubmed Umezawa,
Type 2C protein phosphatases directly regulate abscisic acid-activated protein kinases in Arabidopsis.
2009,
Pubmed Vahisalu,
SLAC1 is required for plant guard cell S-type anion channel function in stomatal signalling.
2008,
Pubmed
,
Xenbase Vahisalu,
Ozone-triggered rapid stomatal response involves the production of reactive oxygen species, and is controlled by SLAC1 and OST1.
2010,
Pubmed Vlad,
Protein phosphatases 2C regulate the activation of the Snf1-related kinase OST1 by abscisic acid in Arabidopsis.
2009,
Pubmed Xu,
AtCPK6, a functionally redundant and positive regulator involved in salt/drought stress tolerance in Arabidopsis.
2010,
Pubmed Xue,
Central functions of bicarbonate in S-type anion channel activation and OST1 protein kinase in CO2 signal transduction in guard cell.
2011,
Pubmed Yin,
Structural insights into the mechanism of abscisic acid signaling by PYL proteins.
2009,
Pubmed Yoshida,
ABA-hypersensitive germination3 encodes a protein phosphatase 2C (AtPP2CA) that strongly regulates abscisic acid signaling during germination among Arabidopsis protein phosphatase 2Cs.
2006,
Pubmed Yoshida,
ABA-activated SnRK2 protein kinase is required for dehydration stress signaling in Arabidopsis.
2002,
Pubmed
