Ca<sup>2+</sup>signatures

Qudeimat, Enas; Frank, Wolfgang

doi:10.4161/psb.4.4.8218

Cited by 14 publications

(3 citation statements)

References 13 publications

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“…Upon PM depolarization, the DACCs are activated and allow Ca 2+ to flow into the cytosol from the apoplast or from intracellular organelles, including vacuoles and endoplasmic reticulum ( Feno et al., 2019 ), causing a transient elevation of the free [Ca 2+ ] cyt ( White, 2004 ). The spatiotemporal pattern of the Ca 2+ flux creates a unique “Ca 2+ signature” that is proportional to the extent and duration of the PM depolarization, which, in turn, is sensitive to and reflects the concentration of the elicitor ( Qudeimat and Frank, 2009 ). Changes in [Ca 2+ ] cyt occur during the transduction of a broad range of biotic and abiotic stresses ( Sanders et al., 2002 ).…”

Section: Discussionmentioning

confidence: 99%

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Lamar,

Gralian,

Hockaday

et al. 2024

Front. Plant Sci.

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IntroductionHumic substances (HS) are increasingly being applied as crop plant biostimulants because they have been shown to increase plant productivity, especially under environmentally stressful conditions. There has been intense interest in elucidating the HS molecular structures responsible for eliciting the plant biostimulant response (PBR). The polar and weakly acidic carboxylic (COOH) and phenolic hydroxyl (ArOH) functional groups play major roles in the acid nature, pH dependent solubilities, conformation, and metal- and salt-binding capabilities of HS. Reports on the role played by these groups in the PBR of HS found growth parameters being both positively and negatively correlated with COOH and ArOH functionalities.Materials and methodsTo investigate the role of COOH and ArOH in HS biostimulant activity we used a humic acid (HA), purified from an oxidized sub bituminous coal to prepare HAs with COOH groups methylated (AHA), ArOH groups acetylated (OHA), and with both COOH and ArOH groups methylated (FHA). The original HA was designated (NHA). The four HAs were subjected to elemental, 13C-NMR, FTIR, and EPR analyses and their antioxidant properties were assessed using the trolox equivalents antioxidant capacity assay (TEAC). 13C-NMR and FTIR analysis revealed significant alkylation/acetylation. To determine the effects of alkylating/acetylating these functional groups on the HA elicited PBR, the HAs were evaluated in a plant bioassay on corn (Zea mays L.) seedling under nutrient and non-nutrient stressed conditions. Treatments consisted of the four HAs applied to the soil surface at a concentration of 80 mg C L−1, in 50 ml DI H2O with the control plants receiving 50ml DI H2O.ResultsThe HA-treated plants, at both fertilization rates, were almost always significantly larger than their respective control plants. However, the differences produced under nutrient stress were always much greater than those produced under nutrient sufficiency, supporting previous reports that HA can reduce the effects of stress on plant growth. In addition, for the most part, the HAs with the alkylated/acetylated groups produced plants equal to or larger than plants treated with NHA.ConclusionThese results suggests that COOH and ArOH groups play a limited or no role in the HA elicited PBR. Alternatively, the HA pro-oxidant to antioxidant ratio may play a role in the magnitude of the biostimulant response.

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Section: Discussionmentioning

confidence: 99%

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Lamar,

Gralian,

Hockaday

et al. 2024

Front. Plant Sci.

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“…Although higher concentrations of Ca 2+ are harmful to plants and animals, it is essential to maintain a proper Ca 2+ concentration in the cytoplasm for these organisms (Kudla et al, 2010). There are numerous review articles about Ca 2+ signals which have made a commendable summary of this messenger in different focuses (Qudeimat and Frank, 2009; Dodd et al, 2010; Kudla et al, 2010; Batistic and Kudla, 2012).…”

Section: Ca2+/cam Complex Regulates Nadk Activitymentioning

confidence: 99%

“…After sensing development-related signals and stimulation by biotic/abiotic stresses, the organisms stimulate the opening of Ca 2+ channels and pumps located on plasma membrane and/or endomembrane systems to further induce some rapid and transient changes in intracellular Ca 2+ concentration (Ca 2+ transients), ultimately producing a stimulating specific physiological response (DeFalco et al, 2009; Dodd et al, 2010; Batistic and Kudla, 2012). The temporal and spatial distribution changes in cellular Ca 2+ concentrations caused by specific stimuli are defined as “Ca 2+ signatures” (Qudeimat and Frank, 2009; Kudla et al, 2010; Batistic and Kudla, 2012). These Ca 2+ signatures are detected, decoded and transmitted to affect downstream protein-protein interactions, phosphorylation cascades, or transcriptional responses by a diversity of Ca 2+ sensors which further bind Ca 2+ using the evolutionarily conserved EF-hand motif.…”

Section: Ca2+/cam Complex Regulates Nadk Activitymentioning

confidence: 99%

Calmodulin Is the Fundamental Regulator of NADK-Mediated NAD Signaling in Plants

Nie

Zhang

et al. 2019

Front. Plant Sci.

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Calcium (Ca 2+ ) signaling and nicotinamide adenine dinucleotide (NAD) signaling are two basic signal regulation pathways in organisms, playing crucial roles in signal transduction, energy metabolism, stress tolerance, and various developmental processes. Notably, calmodulins (CaMs) and NAD kinases (NADKs) are important hubs for connecting these two types of signaling networks, where CaMs are the unique activators of NADKs. NADK is a key enzyme for NADP (including NADP + and NADPH) biosynthesis by phosphorylating NAD (including NAD + and NADH) and therefore, maintains the balance between NAD pool and NADP pool through an allosteric regulation mode. In addition, the two respective derivatives from NAD + (substrate of NADK) and NADP + (product of NADK), cyclic ADP-ribose (cADPR) and nicotinic acid adenine dinucleotide phosphate (NAADP), have been considered to be the important messengers for intracellular Ca 2+ homeostasis which could finally influence the combination between CaM and NADK, forming a feedback regulation mechanism. In this review article, we briefly summarized the major research advances related to the feedback regulation pathway, which is activated by the interaction of CaM and NADK during plant development and signaling. The theories and fact will lay a solid foundation for further studies related to CaM and NADK and their regulatory mechanisms as well as the NADK-mediated NAD signaling behavior in plant development and response to stress.

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Uptake, Distribution, and Physiological Functions of Potassium, Calcium, and Magnesium

Maathuis

Podar

2011

The Molecular and Physiological Basis of Nutrient Use Efficiency in Crops

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Ca²⁺signatures

Cited by 14 publications

References 13 publications

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Calmodulin Is the Fundamental Regulator of NADK-Mediated NAD Signaling in Plants

Uptake, Distribution, and Physiological Functions of Potassium, Calcium, and Magnesium

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Ca2+signatures

Cited by 14 publications

References 13 publications

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Investigation into the role of carboxylic acid and phenolic hydroxyl groups in the plant biostimulant activity of a humic acid purified from an oxidized sub-bituminous coal

Calmodulin Is the Fundamental Regulator of NADK-Mediated NAD Signaling in Plants

Uptake, Distribution, and Physiological Functions of Potassium, Calcium, and Magnesium

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Product

Resources

About

Ca²⁺signatures