1. ABI1 and PP2CA phosphatases are negative regulators of Snf1-related protein kinase1 signaling in Arabidopsis
- Author
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Pierre Crozet, Ana Confraria, Victoria Lumbreras, Agnese Rabissi, Elena Baena-González, Alexandre Elias, Mattia Adamo, Miguel González-Guzmán, Americo Rodrigues, Leonor Margalha, Regina Antoni, Pedro L. Rodriguez, Claudia Martinho, European Commission, Fundação para a Ciência e a Tecnologia (Portugal), Generalitat de Catalunya, Ministerio de Ciencia e Innovación (España), and Consejo Superior de Investigaciones Científicas (España)
- Subjects
0106 biological sciences ,Protein subunit ,Arabidopsis ,Plant Science ,Protein Serine-Threonine Kinases ,01 natural sciences ,03 medical and health sciences ,Plant Growth Regulators ,Gene Expression Regulation, Plant ,Stress, Physiological ,Phosphoprotein Phosphatases ,Phosphorylation ,Psychological repression ,Research Articles ,030304 developmental biology ,Regulation of gene expression ,0303 health sciences ,Reporter gene ,biology ,Arabidopsis Proteins ,fungi ,food and beverages ,Cell Biology ,biology.organism_classification ,Protein-Serine-Threonine Kinases ,ABI1 ,3. Good health ,Biochemistry ,Signal transduction ,010606 plant biology & botany ,Abscisic Acid ,Signal Transduction - Abstract
Plant survival under environmental stress requires the integration of multiple signaling pathways into a coordinated response, but the molecular mechanisms underlying this integration are poorly understood. Stress-derived energy deprivation activates the Snf1-related protein kinases1 (SnRK1s), triggering a vast transcriptional and metabolic reprogramming that restores homeostasis and promotes tolerance to adverse conditions. Here, we show that two clade A type 2C protein phosphatases (PP2Cs), established repressors of the abscisic acid (ABA) hormonal pathway, interact with the SnRK1 catalytic subunit causing its dephosphorylation and inactivation. Accordingly, SnRK1 repression is abrogated in double and quadruple pp2c knockout mutants, provoking, similarly to SnRK1 overexpression, sugar hypersensitivity during early seedling development. Reporter gene assays and SnRK1 target gene expression analyses further demonstrate that PP2C inhibition by ABA results in SnRK1 activation, promoting SnRK1 signaling during stress and once the energy deficit subsides. Consistent with this, SnRK1 and ABA induce largely overlapping transcriptional responses. Hence, the PP2C hub allows the coordinated activation of ABA and energy signaling, strengthening the stress response through the cooperation of two key and complementary pathways., E.B.-G. was supported by grants from Marie Curie IRG, the EMBO Installation program, Marie Curie Actions FP7-People-2010-ITN, the Fundação para a Ciência e a Tecnologia (FCT-PTDC/AGR-AAM/104939/2008), and the Portugal-Spain Bilateral Collaboration program Ações integradas (Ação E-26/10). A.C. was supported by SFRH/BPD/47280/2008, C.M. was supported by SFRH/BD/33563/2008, L.M. was supported by SFRH/BD/51627/2011, and P.C. was supported by SFRH/BPD/79255/2011. A. Rabissi was supported by a Generalitat de Catalunya PhD grant (FI-AR067443). P.L.R. was supported by the Ministerio de Ciencia e Innovación (grants BIO2011-23446 and PT2009-0155), R.A. was supported by the Junta para Ampliación de Estudios e Investigaciones Científicas-Consejo Superior de Investigaciones Cientificas fellowship, and M.G.-G. was supported by a Juan de la Cierva contract.
- Published
- 2013