Gene Symbol: OST1
Description: Protein kinase superfamily protein
Alias: ATOST1, F17I5.140, F17I5_140, OPEN STOMATA 1, P44, SNF1-RELATED PROTEIN KINASE 2.6, SNRK2-6, SNRK2.6, SRK2E, SUCROSE NONFERMENTING 1-RELATED PROTEIN KINASE 2-6, Protein kinase superfamily protein
Species: thale cress

Top Publications

  1. Fujii H, Chinnusamy V, Rodrigues A, Rubio S, Antoni R, Park S, et al. In vitro reconstitution of an abscisic acid signalling pathway. Nature. 2009;462:660-4 pubmed publisher
    ..6/OST1 and the transcription factor ABF2/AREB1, we can reconstitute ABA-triggered phosphorylation of the transcription ..
  2. Yoshida R, Hobo T, Ichimura K, Mizoguchi T, Takahashi F, Aronso J, et al. ABA-activated SnRK2 protein kinase is required for dehydration stress signaling in Arabidopsis. Plant Cell Physiol. 2002;43:1473-83 pubmed
    ..analysis using a specific antibody revealed that the p44 is encoded by a SnRK2-type protein kinase gene, SRK2E. The srk2e mutation resulted in a wilty phenotype mainly due to loss of stomatal closure in response to a rapid ..
  3. Lee S, Lan W, Buchanan B, Luan S. A protein kinase-phosphatase pair interacts with an ion channel to regulate ABA signaling in plant guard cells. Proc Natl Acad Sci U S A. 2009;106:21419-24 pubmed publisher
    ..Earlier genetic analyses uncovered a protein kinase (OST1) and several 2C-type phosphatases, as respective positive and negative regulators of ABA-induced stomatal closure...
  4. Melcher K, Ng L, Zhou X, Soon F, Xu Y, Suino Powell K, et al. A gate-latch-lock mechanism for hormone signalling by abscisic acid receptors. Nature. 2009;462:602-8 pubmed publisher
    ..Together, our results identify a conserved gate-latch-lock mechanism underlying ABA signalling. ..
  5. Belin C, de Franco P, Bourbousse C, Chaignepain S, Schmitter J, Vavasseur A, et al. Identification of features regulating OST1 kinase activity and OST1 function in guard cells. Plant Physiol. 2006;141:1316-27 pubmed
    ..In Arabidopsis (Arabidopsis thaliana) guard cells, OPEN STOMATA 1 (OST1)/SRK2E/SnRK2-6 is a critical positive regulator of ABA signal transduction...
  6. Boudsocq M, Barbier Brygoo H, Laurière C. Identification of nine sucrose nonfermenting 1-related protein kinases 2 activated by hyperosmotic and saline stresses in Arabidopsis thaliana. J Biol Chem. 2004;279:41758-66 pubmed
    ..The probable involvement of the different Arabidopsis SnRK2 in several abiotic transduction pathways is discussed. ..
  7. Nakashima K, Fujita Y, Kanamori N, Katagiri T, Umezawa T, Kidokoro S, et al. Three Arabidopsis SnRK2 protein kinases, SRK2D/SnRK2.2, SRK2E/SnRK2.6/OST1 and SRK2I/SnRK2.3, involved in ABA signaling are essential for the control of seed development and dormancy. Plant Cell Physiol. 2009;50:1345-63 pubmed publisher
    ..SRK2D/SnRK2.2, SRK2E/SnRK2.6/OST1 and SRK2I/SnRK2...
  8. Sato A, Sato Y, Fukao Y, Fujiwara M, Umezawa T, Shinozaki K, et al. Threonine at position 306 of the KAT1 potassium channel is essential for channel activity and is a target site for ABA-activated SnRK2/OST1/SnRK2.6 protein kinase. Biochem J. 2009;424:439-48 pubmed publisher
    ..These results suggest that negative regulation of KAT1 activity, required for stomatal closure, probably occurs by phosphorylation of KAT1 Thr306 by the stress-activated endogenous SnRK2.6 protein kinase. ..
  9. Acharya B, Jeon B, Zhang W, Assmann S. Open Stomata 1 (OST1) is limiting in abscisic acid responses of Arabidopsis guard cells. New Phytol. 2013;200:1049-63 pubmed publisher
    b>Open Stomata 1 (OST1) (SnRK2...

More Information


  1. Yoshida R, Umezawa T, Mizoguchi T, Takahashi S, Takahashi F, Shinozaki K. The regulatory domain of SRK2E/OST1/SnRK2.6 interacts with ABI1 and integrates abscisic acid (ABA) and osmotic stress signals controlling stomatal closure in Arabidopsis. J Biol Chem. 2006;281:5310-8 pubmed
    ..In contrast, SRK2E/OST1/SnRK2...
  2. Soon F, Ng L, Zhou X, West G, Kovach A, Tan M, et al. Molecular mimicry regulates ABA signaling by SnRK2 kinases and PP2C phosphatases. Science. 2012;335:85-8 pubmed publisher
    ..These structural results provide a simple mechanism that directly couples ABA binding to SnRK2 kinase activation and highlight a new paradigm of kinase-phosphatase regulation through mutual packing of their catalytic sites. ..
  3. Umezawa T, Sugiyama N, Mizoguchi M, Hayashi S, Myouga F, Yamaguchi Shinozaki K, et al. Type 2C protein phosphatases directly regulate abscisic acid-activated protein kinases in Arabidopsis. Proc Natl Acad Sci U S A. 2009;106:17588-93 pubmed publisher
    ..Our results demonstrate that group A PP2Cs act as 'gatekeepers' of subclass III SnRK2s, unraveling an important regulatory mechanism of ABA signaling. ..
  4. Fujita Y, Nakashima K, Yoshida T, Katagiri T, Kidokoro S, Kanamori N, et al. Three SnRK2 protein kinases are the main positive regulators of abscisic acid signaling in response to water stress in Arabidopsis. Plant Cell Physiol. 2009;50:2123-32 pubmed publisher
    ..2, SRK2E/SnRK2.6 and SRK2I/SnRK2.3 (SRK2D/E/I)...
  5. Geiger D, Scherzer S, Mumm P, Stange A, Marten I, Bauer H, et al. Activity of guard cell anion channel SLAC1 is controlled by drought-stress signaling kinase-phosphatase pair. Proc Natl Acad Sci U S A. 2009;106:21425-30 pubmed publisher
    ..Two key components of the ABA signaling pathway are the protein kinase OST1 (open stomata 1) and the protein phosphatase ABI1 (ABA insensitive 1)...
  6. Vlad F, Rubio S, Rodrigues A, Sirichandra C, Belin C, Robert N, et al. Protein phosphatases 2C regulate the activation of the Snf1-related kinase OST1 by abscisic acid in Arabidopsis. Plant Cell. 2009;21:3170-84 pubmed publisher
    ..Interestingly, this analysis designated the activation loop of the ABA activated kinase OST1, related to Snf1 and AMPK kinases, as a putative HAB1 substrate...
  7. Vahisalu T, Puzõrjova I, Brosché M, Valk E, Lepiku M, Moldau H, et al. Ozone-triggered rapid stomatal response involves the production of reactive oxygen species, and is controlled by SLAC1 and OST1. Plant J. 2010;62:442-53 pubmed publisher
    ..the SLAC1 protein, essential for guard cell plasma membrane S-type anion channel function, and the protein kinase OST1 were required for the ROS-induced fast stomatal closure...
  8. Mustilli A, Merlot S, Vavasseur A, Fenzi F, Giraudat J. Arabidopsis OST1 protein kinase mediates the regulation of stomatal aperture by abscisic acid and acts upstream of reactive oxygen species production. Plant Cell. 2002;14:3089-99 pubmed
    ..Using infrared thermography, we isolated two allelic Arabidopsis mutants (ost1-1 and ost1-2) impaired in the ability to limit their transpiration upon drought...
  9. Nishimura N, Sarkeshik A, Nito K, Park S, Wang A, Carvalho P, et al. PYR/PYL/RCAR family members are major in-vivo ABI1 protein phosphatase 2C-interacting proteins in Arabidopsis. Plant J. 2010;61:290-9 pubmed publisher
    ..We confirm previous studies in yeast and now show that ABI1 interacts with the ABA-signalling kinases OST1, SnRK2.2 and SnRK2.3 in plants...
  10. Sirichandra C, Gu D, Hu H, Davanture M, Lee S, Djaoui M, et al. Phosphorylation of the Arabidopsis AtrbohF NADPH oxidase by OST1 protein kinase. FEBS Lett. 2009;583:2982-6 pubmed publisher
    ..The ABA-activated SnRK2 protein kinase open stomata 1 (OST1) (SRK2E/SnRK2.6) acts upstream of ROS in guard cell ABA signaling...
  11. Liang S, Lu K, Wu Z, Jiang S, Yu Y, Bi C, et al. A link between magnesium-chelatase H subunit and sucrose nonfermenting 1 (SNF1)-related protein kinase SnRK2.6/OST1 in Arabidopsis guard cell signalling in response to abscisic acid. J Exp Bot. 2015;66:6355-69 pubmed publisher
    ..A member of the sucrose nonfermenting 1 (SNF1)-related protein kinase 2 family, SnRK2.6/open stomata 1 (OST1)/SRK2E, which plays a critical role in ABA signalling in Arabidopsis guard cells, interacts with ABAR/..
  12. Shang Y, Dai C, Lee M, Kwak J, Nam K. BRI1-Associated Receptor Kinase 1 Regulates Guard Cell ABA Signaling Mediated by Open Stomata 1 in Arabidopsis. Mol Plant. 2016;9:447-460 pubmed publisher
    ..ABA-induced OST1 expression and reactive oxygen species (ROS) production were also impaired in bak1...
  13. Geiger D, Scherzer S, Mumm P, Marten I, Ache P, Matschi S, et al. Guard cell anion channel SLAC1 is regulated by CDPK protein kinases with distinct Ca2+ affinities. Proc Natl Acad Sci U S A. 2010;107:8023-8 pubmed publisher
    ..b>Open stomata 1 protein kinase (OST1) and ABI1 protein phosphatase (ABA insensitive 1) represent key components of calcium-..
  14. Xie X, Wang Y, Williamson L, Holroyd G, Tagliavia C, Murchie E, et al. The identification of genes involved in the stomatal response to reduced atmospheric relative humidity. Curr Biol. 2006;16:882-7 pubmed
    ..Both genes encode proteins known to be involved in guard cell ABA signaling. OST1 encodes a protein kinase involved in ABA-mediated stomatal closure while ABA2 encodes an enzyme involved in ABA ..
  15. Lee S, Lim C, Lan W, He K, Luan S. ABA signaling in guard cells entails a dynamic protein-protein interaction relay from the PYL-RCAR family receptors to ion channels. Mol Plant. 2013;6:528-38 pubmed publisher
    ..events involving ABA signaling components, including protein phosphatase 2C members and a SnRK2-type kinase (OST1)...
  16. Zheng Z, Xu X, Crosley R, Greenwalt S, Sun Y, Blakeslee B, et al. The protein kinase SnRK2.6 mediates the regulation of sucrose metabolism and plant growth in Arabidopsis. Plant Physiol. 2010;153:99-113 pubmed publisher
    ..6 mediates hormonal and metabolic regulation of plant growth and development and that, besides the SnRK1 kinases, SnRK2.6 is also implicated in the regulation of metabolic homeostasis in plants. ..
  17. Zhou X, Soon F, Ng L, Kovach A, Suino Powell K, Li J, et al. Catalytic mechanism and kinase interactions of ABA-signaling PP2C phosphatases. Plant Signal Behav. 2012;7:581-8 pubmed publisher
    ..6-HAB1 complex, we present the catalytic mechanism of PP2C and provide new insight into PP2C-SnRK2 interactions and possible roles of other SnRK2 kinases in ABA signaling. ..
  18. Ding Y, Li H, Zhang X, Xie Q, Gong Z, Yang S. OST1 kinase modulates freezing tolerance by enhancing ICE1 stability in Arabidopsis. Dev Cell. 2015;32:278-89 pubmed publisher
    ..Here we report that OST1 (open stomata 1), a well-known Ser/Thr protein kinase in ABA signaling, acts upstream of CBFs to positively regulate freezing ..
  19. Melcher K, Xu Y, Ng L, Zhou X, Soon F, Chinnusamy V, et al. Identification and mechanism of ABA receptor antagonism. Nat Struct Mol Biol. 2010;17:1102-8 pubmed publisher
    ..Together, our results establish a new concept of ABA receptor antagonism, illustrate its underlying mechanisms and provide a rational framework for discovering novel ABA receptor ligands. ..
  20. Takahashi Y, Ebisu Y, Shimazaki K. Reconstitution of Abscisic Acid Signaling from the Receptor to DNA via bHLH Transcription Factors. Plant Physiol. 2017;174:815-822 pubmed publisher
    ..AKS1 was bound to SnRK2.6 in vivo. Three ABA-responsive SnRK2s (SnRK2.2/SRK2D, SnRK2.3/SRK2I, and SnRK2.6/SRK2E/OST1) phosphorylated AKS1 in vitro, and the phosphorylation was eliminated by the triple mutation of SnRK2s in ..
  21. Sun H, Wang X, Ding W, Zhu S, Zhao R, Zhang Y, et al. Identification of an important site for function of the type 2C protein phosphatase ABI2 in abscisic acid signalling in Arabidopsis. J Exp Bot. 2011;62:5713-25 pubmed publisher
  22. Vlad F, Droillard M, Valot B, Khafif M, Rodrigues A, Brault M, et al. Phospho-site mapping, genetic and in planta activation studies reveal key aspects of the different phosphorylation mechanisms involved in activation of SnRK2s. Plant J. 2010;63:778-90 pubmed publisher
    ..6 and SnRK2.10, which may be conserved between the two subgroups of SnRK2s depending on their ABA-responsiveness. ..
  23. Yin Y, Adachi Y, Nakamura Y, Munemasa S, Mori I, Murata Y. Involvement of OST1 Protein Kinase and PYR/PYL/RCAR Receptors in Methyl Jasmonate-Induced Stomatal Closure in Arabidopsis Guard Cells. Plant Cell Physiol. 2016;57:1779-90 pubmed publisher
    ..using the quadruple ABA receptor mutant pyr1 pyl1 pyl2 pyl4 and ABA-activated protein kinase mutants ost1-2 and srk2e. In the quadruple mutant, MeJA-induced stomatal closure, H2O2 production, nitric oxide (NO) production, cytosolic ..
  24. Hua D, Wang C, He J, Liao H, Duan Y, Zhu Z, et al. A plasma membrane receptor kinase, GHR1, mediates abscisic acid- and hydrogen peroxide-regulated stomatal movement in Arabidopsis. Plant Cell. 2012;24:2546-61 pubmed publisher
    ..Our study identifies a critical component in ABA and H2O2 signaling that is involved in stomatal movement and resolves a long-standing mystery about the differential functions of ABI1 and ABI2 in this process. ..
  25. Melotto M, Underwood W, Koczan J, Nomura K, He S. Plant stomata function in innate immunity against bacterial invasion. Cell. 2006;126:969-80 pubmed
    ..surface molecules, which requires the FLS2 receptor, production of nitric oxide, and the guard-cell-specific OST1 kinase...
  26. Osakabe Y, Arinaga N, Umezawa T, Katsura S, Nagamachi K, Tanaka H, et al. Osmotic stress responses and plant growth controlled by potassium transporters in Arabidopsis. Plant Cell. 2013;25:609-24 pubmed publisher
    ..The protein kinase SNF1-related protein kinases 2E (SRK2E), a key component of ABA signaling, interacted with and phosphorylated KUP6, suggesting that KUP functions are ..
  27. Wang P, Du Y, Hou Y, Zhao Y, Hsu C, Yuan F, et al. Nitric oxide negatively regulates abscisic acid signaling in guard cells by S-nitrosylation of OST1. Proc Natl Acad Sci U S A. 2015;112:613-8 pubmed publisher
    ..Here, we show that NO negatively regulates ABA signaling in guard cells by inhibiting open stomata 1 (OST1)/sucrose nonfermenting 1 (SNF1)-related protein kinase 2.6 (SnRK2.6) through S-nitrosylation...
  28. Tajdel M, Mituła F, Ludwików A. Regulation of Arabidopsis MAPKKK18 by ABI1 and SnRK2, components of the ABA signaling pathway. Plant Signal Behav. 2016;11:e1139277 pubmed publisher
    ..SnRK2.6 kinase also seems to be important for the regulation of MAPKKK18 function. In this review we summarize the mechanisms that are exclusively involved in MAPKKK18 kinase regulation and that ensure specificity in its activation. ..
  29. Merlot S, Mustilli A, Genty B, North H, Lefebvre V, Sotta B, et al. Use of infrared thermal imaging to isolate Arabidopsis mutants defective in stomatal regulation. Plant J. 2002;30:601-9 pubmed
    ..addition to the previously known abi1-1 mutation, we isolated mutations at two novel loci designated as OST1 (OPEN STOMATA 1) and OST2...
  30. Feng C, Chen Y, Wang C, Kong Y, Wu W, Chen Y. Arabidopsis RAV1 transcription factor, phosphorylated by SnRK2 kinases, regulates the expression of ABI3, ABI4, and ABI5 during seed germination and early seedling development. Plant J. 2014;80:654-68 pubmed publisher
    ..Together, these results demonstrated that the Arabidopsis RAV1 transcription factor plays an important role in ABA signaling by modulating the expression of ABI3, ABI4, and ABI5, and that its activity is negatively affected by SnRK2s. ..
  31. Sirichandra C, Davanture M, Turk B, Zivy M, Valot B, Leung J, et al. The Arabidopsis ABA-activated kinase OST1 phosphorylates the bZIP transcription factor ABF3 and creates a 14-3-3 binding site involved in its turnover. PLoS ONE. 2010;5:e13935 pubmed publisher
    ..Here, the substrate preference of OST1 was interrogated at a genome-wide scale...
  32. Riera M, Redko Y, Leung J. Arabidopsis RNA-binding protein UBA2a relocalizes into nuclear speckles in response to abscisic acid. FEBS Lett. 2006;580:4160-5 pubmed
    ..Our results showed that despite the resemblance between the corresponding Vicia and Arabidopsis proteins, it appears that the function of UBA2a is independent of OST1 phosphorylation.
  33. Sridharamurthy M, Kovach A, Zhao Y, Zhu J, Xu H, Swaminathan K, et al. H2O2 inhibits ABA-signaling protein phosphatase HAB1. PLoS ONE. 2014;9:e113643 pubmed publisher
    ..6/OST1 kinase...
  34. Yunta C, Martinez Ripoll M, Albert A. SnRK2.6/OST1 from Arabidopsis thaliana: cloning, expression, purification, crystallization and preliminary X-ray analysis of K50N and D160A mutants. Acta Crystallogr Sect F Struct Biol Cryst Commun. 2011;67:364-8 pubmed publisher
    ..6) gene from Arabidopsis thaliana encodes the serine/threonine protein kinase SnRK2.6/OST1 (OPEN STOMATA 1). It plays a central role in the drought-tolerance mechanism...
  35. West G, Pascal B, Ng L, Soon F, Melcher K, Xu H, et al. Protein conformation ensembles monitored by HDX reveal a structural rationale for abscisic acid signaling protein affinities and activities. Structure. 2013;21:229-35 pubmed publisher
    ..Furthermore, kinase activity is linked to a more stable "closed" conformation. These solution-based studies complement the static crystal structures and provide a more detailed understanding of the ABA signaling pathway. ..
  36. Ye W, Adachi Y, Munemasa S, Nakamura Y, Mori I, Murata Y. Open Stomata 1 Kinase is Essential for Yeast Elicitor-Induced Stomatal Closure in Arabidopsis. Plant Cell Physiol. 2015;56:1239-48 pubmed publisher
    ..A Ca(2+)-independent kinase, Open Stomata 1 (OST1), is involved in stomatal closure induced by various stimuli including ABA...
  37. Xie T, Ren R, Zhang Y, Pang Y, Yan C, Gong X, et al. Molecular mechanism for inhibition of a critical component in the Arabidopsis thaliana abscisic acid signal transduction pathways, SnRK2.6, by protein phosphatase ABI1. J Biol Chem. 2012;287:794-802 pubmed publisher
    ..6 is posited to the catalytic site of ABI1 for dephosphorylation. These studies revealed the molecular basis for PP2Cs-mediated inhibition of SnRK2s and provided important insights into the downstream signal transduction of ABA. ..
  38. Mogami J, Fujita Y, Yoshida T, Tsukiori Y, Nakagami H, Nomura Y, et al. Two distinct families of protein kinases are required for plant growth under high external Mg2+ concentrations in Arabidopsis. Plant Physiol. 2015;167:1039-57 pubmed publisher
    ..These results suggested that SRK2D/E/I- and CIPK26/3/9/23-mediated phosphorylation signaling pathways maintain cellular Mg(2+) homeostasis. ..
  39. Grondin A, Rodrigues O, Verdoucq L, Merlot S, Leonhardt N, Maurel C. Aquaporins Contribute to ABA-Triggered Stomatal Closure through OST1-Mediated Phosphorylation. Plant Cell. 2015;27:1945-54 pubmed publisher
    ..b>Open stomata 1 (OST1)/Snf1-related protein kinase 2.6 (SnRK2...
  40. Suhita D, Raghavendra A, Kwak J, Vavasseur A. Cytoplasmic alkalization precedes reactive oxygen species production during methyl jasmonate- and abscisic acid-induced stomatal closure. Plant Physiol. 2004;134:1536-45 pubmed
    ..ABA) or methyl jasmonate (MJ)-induced stomatal closure were examined in Arabidopsis wild type, ABA-insensitive (ost1-2), and MJ-insensitive mutants (jar1-1) in order to examine a crosstalk between ABA and MJ signal transduction...
  41. Imes D, Mumm P, Böhm J, Al Rasheid K, Marten I, Geiger D, et al. Open stomata 1 (OST1) kinase controls R-type anion channel QUAC1 in Arabidopsis guard cells. Plant J. 2013;74:372-82 pubmed publisher
    Under drought stress, the stress hormone ABA addresses the SnR kinase OST1 via its cytosolic receptor and the protein phosphatase ABI1. Upon activation, OST1 phosphorylates the guard cell S-type anion channel SLAC1...
  42. Ding S, Zhang B, Qin F. Arabidopsis RZFP34/CHYR1, a Ubiquitin E3 Ligase, Regulates Stomatal Movement and Drought Tolerance via SnRK2.6-Mediated Phosphorylation. Plant Cell. 2015;27:3228-44 pubmed publisher
    ..Thus, this study identified a RING-type ubiquitin E3 ligase that functions positively in ABA and drought responses and detailed how its ubiquitin E3 ligase activity is regulated by SnRK2.6-mediated protein phosphorylation. ..
  43. Cai Z, Liu J, Wang H, Yang C, Chen Y, Li Y, et al. GSK3-like kinases positively modulate abscisic acid signaling through phosphorylating subgroup III SnRK2s in Arabidopsis. Proc Natl Acad Sci U S A. 2014;111:9651-6 pubmed publisher
    ..2 and SnRK2.3. These findings provide significant insight into the modulation of ABA signaling by Arabidopsis GSK3-like kinases. ..
  44. Pizzio G, Rodriguez L, Antoni R, Gonzalez Guzman M, Yunta C, Merilo E, et al. The PYL4 A194T mutant uncovers a key role of PYR1-LIKE4/PROTEIN PHOSPHATASE 2CA interaction for abscisic acid signaling and plant drought resistance. Plant Physiol. 2013;163:441-55 pubmed publisher
    ..Thus, we describe a novel approach to enhance plant drought resistance through allele library generation and engineering of a PYL4 mutation that enhances interaction with PP2CA. ..
  45. Laanemets K, Brandt B, Li J, Merilo E, Wang Y, Keshwani M, et al. Calcium-dependent and -independent stomatal signaling network and compensatory feedback control of stomatal opening via Ca2+ sensitivity priming. Plant Physiol. 2013;163:504-13 pubmed publisher
  46. Merilo E, Laanemets K, Hu H, Xue S, Jakobson L, Tulva I, et al. PYR/RCAR receptors contribute to ozone-, reduced air humidity-, darkness-, and CO2-induced stomatal regulation. Plant Physiol. 2013;162:1652-68 pubmed publisher
    ..SLAC1 is activated by OPEN STOMATA1 (OST1) and Ca(2+)-dependent protein kinases...
  47. Tian W, Hou C, Ren Z, Pan Y, Jia J, Zhang H, et al. A molecular pathway for COâ‚‚ response in Arabidopsis guard cells. Nat Commun. 2015;6:6057 pubmed publisher
    ..We also show that HT1 phosphorylates and inactivates OST1, a kinase which is essential for the activation of the SLAC1 anion channel and stomatal closing...
  48. Fujii H, Verslues P, Zhu J. Arabidopsis decuple mutant reveals the importance of SnRK2 kinases in osmotic stress responses in vivo. Proc Natl Acad Sci U S A. 2011;108:1717-22 pubmed publisher
    ..These results demonstrate critical functions of the SnRK2s in mediating osmotic stress signaling and tolerance. ..
  49. Mitula F, Tajdel M, Cieśla A, Kasprowicz Maluśki A, Kulik A, Babula Skowrońska D, et al. Arabidopsis ABA-Activated Kinase MAPKKK18 is Regulated by Protein Phosphatase 2C ABI1 and the Ubiquitin-Proteasome Pathway. Plant Cell Physiol. 2015;56:2351-67 pubmed publisher
    ..The rate of MKKK18 degradation was delayed in the ABI1 knockout line. Overall, we provide evidence that ABI1 regulates the activity and promotes proteasomal degradation of MKKK18. ..
  50. Kuromori T, Sugimoto E, Shinozaki K. Arabidopsis mutants of AtABCG22, an ABC transporter gene, increase water transpiration and drought susceptibility. Plant J. 2011;67:885-94 pubmed publisher
    ..The atabcg22 mutation further increased the water loss of srk2e/ost1 mutants, which were defective in ABA signalling in guard cells...
  51. Wang P, Xue L, Batelli G, Lee S, Hou Y, Van Oosten M, et al. Quantitative phosphoproteomics identifies SnRK2 protein kinase substrates and reveals the effectors of abscisic acid action. Proc Natl Acad Sci U S A. 2013;110:11205-10 pubmed publisher
    ..These results shed new light on the role of the SnRK2 protein kinases and on the downstream effectors of ABA action, and improve our understanding of plant responses to adverse environments. ..
  52. Yu F, Qian L, Nibau C, Duan Q, Kita D, Levasseur K, et al. FERONIA receptor kinase pathway suppresses abscisic acid signaling in Arabidopsis by activating ABI2 phosphatase. Proc Natl Acad Sci U S A. 2012;109:14693-8 pubmed publisher
    ..In search of the target for the FER pathway, we found that the ROP11/ARAC10 protein physically interacted with the ABI2 phosphatase and enhanced its activity, thereby linking the FER pathway with the inhibition of ABA signaling. ..