scholarly journals Members of the abscisic acid co-receptor PP2C protein family mediate salicylic acid-abscisic acid crosstalk

2017 ◽  
Author(s):  
Murli Manohar ◽  
Dekai Wang ◽  
Patricia M. Manosalva ◽  
Hyong Woo Choi ◽  
Erich Kombrink ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Abscisic Acid ◽  
Underlying Mechanism ◽  
Protein Family ◽  
Negative Regulator ◽  
Plant Responses ◽  
Aba Signaling ◽  
Biotic Stresses ◽  
The Face ◽  
Aba Receptors

AbstractThe interplay between abscisic acid (ABA) and salicylic acid (SA) influences plant responses to various (a)biotic stresses; however, the underlying mechanism(s) for this crosstalk is largely unknown. Here we report that type 2C protein phosphatases (PP2Cs), some of which are negative regulators of ABA signaling, bind SA. SA binding suppressed the ABA-enhanced interaction between these PP2Cs and various ABA receptors belonging to the PYR/PYL/RCAR protein family. Additionally, SA suppressed ABA-enhanced degradation of PP2Cs and ABA-induced stabilization of SnRK2s. Supporting SA’s role as a negative regulator of ABA signaling, exogenous SA suppressed ABA-induced gene expression, whereas SA-deficient sid2-1 mutants displayed heightened PP2C degradation and hypersensitivity to ABA-induced suppression of seed germination. Together, these results suggest a new molecular mechanism through which SA antagonizes ABA signaling. A better understanding of the crosstalk between these hormones is important for improving the sustainability of agriculture in the face of climate change.

scholarly journals Members of the abscisic acid co-receptor PP2C protein family mediate salicylic acid-abscisic acid crosstalk

Plant Direct ◽  
2017 ◽  
Vol 1 (5) ◽  
pp. e00020 ◽  
Author(s):  
Murli Manohar ◽  
Dekai Wang ◽  
Patricia M. Manosalva ◽  
Hyong Woo Choi ◽  
Erich Kombrink ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Abscisic Acid ◽  
Protein Family

scholarly journals Arabidopsis exoribonuclease USB1 interacts with the PPR-domain protein SOAR1 to negatively regulate abscisic acid signaling

2020 ◽  
Vol 71 (19) ◽  
pp. 5837-5851
Author(s):  
Yu Ma ◽  
Shang Zhang ◽  
Chao Bi ◽  
Chao Mei ◽  
Shang-Chuan Jiang ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Regulation Of Gene Expression ◽  
Mrna Splicing ◽  
Plant Responses ◽  
Aba Signaling ◽  
Pentatricopeptide Repeat ◽  
Spliceosome Assembly ◽  
Early Seedling ◽  
Post Transcriptional Regulation ◽  
Early Seedling Development

Abstract Signaling by the phytohormone abscisic acid (ABA) involves pre-mRNA splicing, a key process of post-transcriptional regulation of gene expression. However, the regulatory mechanism of alternative pre-mRNA splicing in ABA signaling remains largely unknown. We previously identified a pentatricopeptide repeat protein SOAR1 (suppressor of the ABAR-overexpressor 1) as a crucial player downstream of ABAR (putative ABA receptor) in ABA signaling. In this study, we identified a SOAR1 interaction partner USB1, which is an exoribonuclease catalyzing U6 production for spliceosome assembly. We reveal that together USB1 and SOAR1 negatively regulate ABA signaling in early seedling development. USB1 and SOAR1 are both required for the splicing of transcripts of numerous genes, including those involved in ABA signaling pathways, suggesting that USB1 and SOAR1 collaborate to regulate ABA signaling by affecting spliceosome assembly. These findings provide important new insights into the mechanistic control of alternative pre-mRNA splicing in the regulation of ABA-mediated plant responses to environmental cues.

scholarly journals Abscisic Acid as an Emerging Modulator of the Responses of Plants to Low Oxygen Conditions

2021 ◽  
Vol 12 ◽  
Author(s):  
Miguel González-Guzmán ◽  
Aurelio Gómez-Cadenas ◽  
Vicent Arbona
Keyword(s):  
Abscisic Acid ◽  
Plant Hormone ◽  
Negative Regulator ◽  
Plant Responses ◽  
Low Oxygen ◽  
Positive Role ◽  
Morphological Adaptations ◽  
Oxygen Conditions ◽  
Hyponastic Growth

Different environmental and developmental cues involve low oxygen conditions, particularly those associated to abiotic stress conditions. It is widely accepted that plant responses to low oxygen conditions are mainly regulated by ethylene (ET). However, interaction with other hormonal signaling pathways as gibberellins (GAs), auxin (IAA), or nitric oxide (NO) has been well-documented. In this network of interactions, abscisic acid (ABA) has always been present and regarded to as a negative regulator of the development of morphological adaptations to soil flooding: hyponastic growth, adventitious root emergence, or formation of secondary aerenchyma in different plant species. However, recent evidence points toward a positive role of this plant hormone on the modulation of plant responses to hypoxia and, more importantly, on the ability to recover during the post-hypoxic period. In this work, the involvement of ABA as an emerging regulator of plant responses to low oxygen conditions alone or in interaction with other hormones is reviewed and discussed.

scholarly journals Molecular Basis of the Activation and Dissociation of Dimeric PYL2 Receptor in Abscisic Acid Signaling

2019 ◽  
Author(s):  
Chuankai Zhao ◽  
Diwakar Shukla
Keyword(s):  
Free Energy ◽  
Abscisic Acid ◽  
Critical Role ◽  
Water Molecules ◽  
Plant Responses ◽  
Free Energy Barrier ◽  
Conformational Plasticity ◽  
Dynamics Simulations ◽  
Key Aspects ◽  
Aba Receptors

Phytohormone abscisic acid (ABA) is essential for plant responses to biotic and abiotic stresses. Dimeric receptors are a class of ABA receptors that are important for various ABA responses. While extensive experimental and computational studies have investigated these receptors, it remains not fully understood how ABA leads to their activation and dissociation for interaction with downstream phosphatase. It also remains unknown how networks of water molecules present in the binding site affect ABA perception despite its critical role in protein-ligand binding. Here, we study the activation and the homodimeric association processes of PYL2 receptor as well as its heterodimeric association with the phosphatase HAB1 using molecular dynamics simulations. Free energy landscapes from ~223 μs simulations show that dimerization substantially constrains PYL2 conformational plasticity and stabilizes inactive state, resulting in lower ABA affinity. Using hydration site analysis to characterize receptor solvation thermodynamics, we show that the displacement and reorganization of water molecules upon ABA binding contribute to binding affinity via gain of entropy and enthalpy, respectively. The penalty for expelling water molecules into the bulk causes the free energy barrier to binding (~4-5 kcal/mol). Finally, we establish the thermodynamic model for competitive binding between homodimeric PYL2 association and heterodimeric PYL2-HAB1 association in the absence and presence of ABA. Our results suggest that the binding of ABA destabilizes PYL2 complex and further stabilizes PYL2-HAB1 association, thereby promoting PYL2 dissociation. Overall, this study explains several key aspects on activation of dimeric ABA receptors, which provide new avenues for selective regulation of these receptors.

scholarly journals ABSCISIC ACID INSENSITIVE5 Interacts With RIBOSOMAL S6 KINASE2 to Mediate ABA Responses During Seedling Growth in Arabidopsis

2021 ◽  
Vol 11 ◽  
Author(s):  
Linxuan Li ◽  
Tingting Zhu ◽  
Yun Song ◽  
Li Feng ◽  
Essam Ali Hassan Farag ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Seedling Growth ◽  
Stress Responses ◽  
Underlying Mechanism ◽  
Aba Signaling ◽  
Drought Treatment ◽  
Biochemical Interaction ◽  
Transcriptional Regulatory ◽  
Physiological Analysis ◽  
Transcriptional Regulatory Mechanisms

ABSCISIC ACID INSENSITIVE5 (ABI5) is an important regulator of abscisic acid (ABA) signaling pathway involved in regulating seed germination and postgerminative growth in Arabidopsis, which integrates various phytohormone pathways to balance plant growth and stress responses. However, the transcriptional regulatory mechanisms underlying ABI5 and its interacting proteins remain largely unknown. Here, we found that inhibition of AtTOR could increase ABA content by up-regulating the expression levels of ABA biosynthesis-related genes, and thus activated the expression of ABA-responsive genes. Pharmacological assay showed that abi5-1 mutant was insensitive to TOR inhibitor AZD8055, whereas AtABI5 overexpression lines were hypersensitive to AZD8055 in Arabidopsis. Biochemical interaction assays demonstrated that ABI5 physically interacted with the RIBOSOMAL S6 KINASE2 (S6K2) protein in plant cell. S6K2 positively regulated ABA responses during seedling growth and upregulated ABA-responsive genes expression. Furthermore, genetic and physiological analysis indicated that AtS6K2 overexpression lines enhanced resistance to drought treatment while AtS6K2 interference lines were sensitive to drought. These results indicated that AtABI5 interacted with AtS6K2 to positively modulate ABA responses during seedling growth and shed light on a underlying mechanism of the crosstalk between TOR and ABA signaling pathways in modulating seedling growth in Arabidopsis.

scholarly journals Abscisic Acid Interacts Antagonistically with Salicylic Acid Signaling Pathway in Rice–Magnaporthe grisea Interaction

2010 ◽  
Vol 23 (6) ◽  
pp. 791-798 ◽  
Author(s):  
Chang-Jie Jiang ◽  
Masaki Shimono ◽  
Shoji Sugano ◽  
Mikiko Kojima ◽  
Katsumi Yazawa ◽  
...  
Keyword(s):  
Salicylic Acid ◽  
Abscisic Acid ◽  
Signaling Pathway ◽  
Magnaporthe Grisea ◽  
Culture Media ◽  
Blast Resistance ◽  
Aba Signaling ◽  
Host Infection ◽  
Plant Pathogen Interactions ◽  
Sa Signaling

Plant hormones play pivotal signaling roles in plant–pathogen interactions. Here, we report characterization of an antagonistic interaction of abscisic acid (ABA) with salicylic acid (SA) signaling pathways in the rice–Magnaporthe grisea interaction. Exogenous application of ABA drastically compromised the rice resistance to both compatible and incompatible M. grisea strains, indicating that ABA negatively regulates both basal and resistance gene–mediated blast resistance. ABA markedly suppressed the transcriptional upregulation of WRKY45 and OsNPR1, the two key components of the SA signaling pathway in rice, induced by SA or benzothiadiazole or by blast infection. Overexpression of OsNPR1 or WRKY45 largely negated the enhancement of blast susceptibility by ABA, suggesting that ABA acts upstream of WRKY45 and OsNPR1 in the rice SA pathway. ABA-responsive genes were induced during blast infection in a pattern reciprocal to those of WRKY45 and OsPR1b in the compatible rice–blast interaction but only marginally in the incompatible one. These results suggest that the balance of SA and ABA signaling is an important determinant for the outcome of the rice–M. grisea interaction. ABA was detected in hyphae and conidia of M. grisea as well as in culture media, implying that blast-fungus-derived ABA could play a role in triggering ABA signaling at host infection sites.

scholarly journals Strigolactones and their crosstalk with other phytohormones

2019 ◽  
Vol 124 (5) ◽  
pp. 749-767 ◽  
Author(s):  
L O Omoarelojie ◽  
M G Kulkarni ◽  
J F Finnie ◽  
J Van Staden
Keyword(s):  
Salicylic Acid ◽  
Abscisic Acid ◽  
Plant Responses ◽  
Research Attention ◽  
Molecular Events ◽  
Whole Plant ◽  
Shoot Architecture ◽  
Hormonal Crosstalk ◽  
Morphological Processes ◽  
Parasitic Interactions

Abstract Background Strigolactones (SLs) are a diverse class of butenolide-bearing phytohormones derived from the catabolism of carotenoids. They are associated with an increasing number of emerging regulatory roles in plant growth and development, including seed germination, root and shoot architecture patterning, nutrient acquisition, symbiotic and parasitic interactions, as well as mediation of plant responses to abiotic and biotic cues. Scope Here, we provide a concise overview of SL biosynthesis, signal transduction pathways and SL-mediated plant responses with a detailed discourse on the crosstalk(s) that exist between SLs/components of SL signalling and other phytohormones such as auxins, cytokinins, gibberellins, abscisic acid, ethylene, jasmonates and salicylic acid. Conclusion SLs elicit their control on physiological and morphological processes via a direct or indirect influence on the activities of other hormones and/or integrants of signalling cascades of other growth regulators. These, among many others, include modulation of hormone content, transport and distribution within plant tissues, interference with or complete dependence on downstream signal components of other phytohormones, as well as acting synergistically or antagonistically with other hormones to elicit plant responses. Although much has been done to evince the effects of SL interactions with other hormones at the cell and whole plant levels, research attention must be channelled towards elucidating the precise molecular events that underlie these processes. More especially in the case of abscisic acid, cytokinins, gibberellin, jasmonates and salicylic acid for which very little has been reported about their hormonal crosstalk with SLs.

scholarly journals Initiation and amplification of SnRK2 activation in abscisic acid signaling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Zhen Lin ◽  
Yuan Li ◽  
Yubei Wang ◽  
Xiaolei Liu ◽  
Liang Ma ◽  
...  
Keyword(s):  
Abscisic Acid ◽  
Higher Plants ◽  
Plant Responses ◽  
Activation Loop ◽  
Aba Signaling ◽  
Kinase Activation ◽  
Abscisic Acid Signaling ◽  
Aba Receptor ◽  
Amplification Mechanism

AbstractThe phytohormone abscisic acid (ABA) is crucial for plant responses to environmental challenges. The SNF1-regulated protein kinase 2s (SnRK2s) are key components in ABA-receptor coupled core signaling, and are rapidly phosphorylated and activated by ABA. Recent studies have suggested that Raf-like protein kinases (RAFs) participate in ABA-triggered SnRK2 activation. In vitro kinase assays also suggest the existence of autophosphorylation of SnRK2s. Thus, how SnRK2 kinases are quickly activated during ABA signaling still needs to be clarified. Here, we show that both B2 and B3 RAFs directly phosphorylate SnRK2.6 in the kinase activation loop. This transphosphorylation by RAFs is essential for SnRK2 activation. The activated SnRK2s then intermolecularly trans-phosphorylate other SnRK2s that are not yet activated to amplify the response. High-order Arabidopsis mutants lacking multiple B2 and B3 RAFs show ABA hyposensitivity. Our findings reveal a unique initiation and amplification mechanism of SnRK2 activation in ABA signaling in higher plants.

scholarly journals Tomato Protein Phosphatase 2C (SlPP2C3) negatively regulates fruit ripening onset and fruit gloss

2020 ◽  
Author(s):  
Bin Liang ◽  
Yufei Sun ◽  
Juan Wang ◽  
Yu Zheng ◽  
Wenbo Zhang ◽  
...  
Keyword(s):  
Fruit Ripening ◽  
Vital Role ◽  
Negative Regulator ◽  
Aba Signaling ◽  
Rna Seq ◽  
Enhanced Sensitivity ◽  
Physiological Processes ◽  
Appearance Quality ◽  
Aba Receptors

AbstractAbscisic acid (ABA) plays a vital role in coordinating physiological processes during fresh fruit ripening. ABA can bind to ABA receptors which interacts and inhibits their co-receptors type 2C phosphatases (PP2Cs). However, the dissected mechanism of PP2C during fruit ripening is unclear. In this study, we identify the role of SlPP2C3, a tomato type 2C phosphatase, as a negative regulator of ABA signaling and fruit ripening. SlPP2C3 selectively interacted with monomeric ABA receptors and SlSnRK2.8 kinase in both yeast and tobacco epidermal cells. Expressions of SlPP2C3 were observed in all tissues, and it negatively correlated with the fruit ripening which was induced by exogenous ABA. Tomato plants with suppressed SlPP2C3 expression exhibited enhanced sensitivity to ABA, while SlPP2C3 over-expressed plants were less sensitive to ABA. Meaningfully, lack of SlPP2C3 expression causes the acceleration of fruit ripening onset via the alternation of ABA signaling activity, and the fruit gloss is affected by the changes of outer epidermis structure. RNA-seq analysis found significant different expression of cuticle-related genes in pericarp between wild-type and SlPP2C3 suppressed lines. Taken together, our finding demonstrate that SlPP2C3 plays an important role in the regulation of fruit ripening and fruit appearance quality in tomato.

scholarly journals Analysis of Phytohormone Signal Transduction in Sophora alopecuroides under Salt Stress

2021 ◽  
Vol 22 (14) ◽  
pp. 7313
Author(s):  
Youcheng Zhu ◽  
Qingyu Wang ◽  
Ziwei Gao ◽  
Ying Wang ◽  
Yajing Liu ◽  
...  
Keyword(s):  
Signal Transduction ◽  
Salicylic Acid ◽  
Abscisic Acid ◽  
Salt Stress ◽  
Stress Responses ◽  
Resistance Breeding ◽  
Plant Responses ◽  
Salt Stress Response ◽  
Sophora Alopecuroides

Salt stress seriously restricts crop yield and quality, leading to an urgent need to understand its effects on plants and the mechanism of plant responses. Although phytohormones are crucial for plant responses to salt stress, the role of phytohormone signal transduction in the salt stress responses of stress-resistant species such as Sophora alopecuroides has not been reported. Herein, we combined transcriptome and metabolome analyses to evaluate expression changes of key genes and metabolites associated with plant hormone signal transduction in S. alopecuroides roots under salt stress for 0 h to 72 h. Auxin, cytokinin, brassinosteroid, and gibberellin signals were predominantly involved in regulating S. alopecuroides growth and recovery under salt stress. Ethylene and jasmonic acid signals may negatively regulate the response of S. alopecuroides to salt stress. Abscisic acid and salicylic acid are significantly upregulated under salt stress, and their signals may positively regulate the plant response to salt stress. Additionally, salicylic acid (SA) might regulate the balance between plant growth and resistance by preventing reduction in growth-promoting hormones and maintaining high levels of abscisic acid (ABA). This study provides insight into the mechanism of salt stress response in S. alopecuroides and the corresponding role of plant hormones, which is beneficial for crop resistance breeding.

Sign in / Sign up

Export Citation Format

Share Document