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Bourke JP. Understanding the Electrical Substrates Contributing to "Ablation-Resistant" Atrial Fibrillation? Am J Cardiol 2024:S0002-9149(24)00283-2. [PMID: 38643927 DOI: 10.1016/j.amjcard.2024.04.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 03/29/2024] [Accepted: 04/16/2024] [Indexed: 04/23/2024]
Abstract
Atrial fibrillation (AF) was largely ignored by cardiac electrophysiologists until it was first suggested in 1998 that it might be amenable to catheter ablation. In the 25 years since then, a vast body of knowledge has emerged, initially reporting the "hypes and hopes" that ablation was appropriate for all but more recently acknowledging that not all patients benefit from this approach. The AF "epidemic" and more holistic understanding of the complex contributors to its development question whether it is even meaningful to consider AF a single condition that is always responsive to ablation management. In this issue, Masuda et al11 provide novel insights into the electrophysiologic "footprints" that they found in the body of the left atrium of patients who underwent a second ablation procedure after achieving pulmonary vein isolation. In conclusion, the findings require prospective validation but may show a way of achieving antiarrhythmic success in a cohort of patients responding unpredictably to current ablation strategies.
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Affiliation(s)
- John P Bourke
- Department of Cardiology, Freeman Hospital, Newcastle upon Tyne NHS Hospitals Foundation Trust, United Kingdom.
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2
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Pachú JK, Macedo FC, Malaquias JB, Ramalho FS, Oliveira RF, Godoy WA, Salustino AS. Electrical signalling and plant response to herbivory: A short review. Plant Signal Behav 2023; 18:2277578. [PMID: 38051638 PMCID: PMC10732603 DOI: 10.1080/15592324.2023.2277578] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 10/18/2023] [Indexed: 12/07/2023]
Abstract
For a long time, electrical signaling was neglected at the expense of signaling studies in plants being concentrated with chemical and hydraulic signals. Studies conducted in recent years have revealed that plants are capable of emitting, processing, and transmitting bioelectrical signals to regulate a wide variety of physiological functions. Many important biological and physiological phenomena are accompanied by these cellular electrical manifestations, which supports the hypothesis about the importance of bioelectricity as a fundamental 'model' for response the stresses environmental and for activities regeneration of these organisms. Electrical signals have also been characterized and discriminated against in genetically modified plants under stress mediated by sucking insects and/or by the application of systemic insecticides. Such results can guide future studies that aim to elucidate the factors involved in the processes of resistance to stress and plant defense, thus aiding in the development of successful strategies in integrated pest management. Therefore, this mini review includes the results of studies aimed at electrical signaling in response to biotic stress. We also demonstrated how the generation and propagation of electrical signals takes place and included a description of how these electrical potentials are measured.
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Affiliation(s)
- Jéssica K.S Pachú
- Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Piracicaba, São Paulo, Brazil
| | - Francynes C.O. Macedo
- Department of Biological Sciences, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Piracicaba, São Paulo, Brazil
| | - José B Malaquias
- Entomology Laboratory, Agrarian Science Center, Federal University of Paraíba, Areia, Brazil
| | - Francisco S. Ramalho
- Biological Control Unit, Empresa Brasileira de Pesquisa Agropecuaria, Campina Grande, Brazil
| | - Ricardo F. Oliveira
- Department of Biological Sciences, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Piracicaba, São Paulo, Brazil
| | - Wesley A.C Godoy
- Department of Entomology and Acarology, Luiz de Queiroz College of Agriculture (ESALQ), University of São Paulo (USP), Piracicaba, São Paulo, Brazil
| | - Angélica S. Salustino
- Entomology Laboratory, Agrarian Science Center, Federal University of Paraíba, Areia, Brazil
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3
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Sukhova EM, Yudina LM, Sukhov VS. Changes in Activity of the Plasma Membrane H+-ATPase as a Link Between Formation of Electrical Signals and Induction of Photosynthetic Responses in Higher Plants. Biochemistry (Mosc) 2023; 88:1488-1503. [PMID: 38105019 DOI: 10.1134/s0006297923100061] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 09/05/2023] [Accepted: 09/13/2023] [Indexed: 12/19/2023]
Abstract
Action of numerous adverse environmental factors on higher plants is spatially-heterogenous; it means that induction of a systemic adaptive response requires generation and transmission of the stress signals. Electrical signals (ESs) induced by local action of stressors include action potential, variation potential, and system potential and they participate in formation of fast physiological changes at the level of a whole plant, including photosynthetic responses. Generation of these ESs is accompanied by the changes in activity of H+-ATPase, which is the main system of electrogenic proton transport across the plasma membrane. Literature data show that the changes in H+-ATPase activity and related changes in intra- and extracellular pH play a key role in the ES-induced inactivation of photosynthesis in non-irritated parts of plants. This inactivation is caused by both suppression of CO2 influx into mesophyll cells in leaves, which can be induced by the apoplast alkalization and, probably, cytoplasm acidification, and direct influence of acidification of stroma and lumen of chloroplasts on light and, probably, dark photosynthetic reactions. The ES-induced inactivation of photosynthesis results in the increasing tolerance of photosynthetic machinery to the action of adverse factors and probability of the plant survival.
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Affiliation(s)
- Ekaterina M Sukhova
- Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603022, Russia
| | - Lyubov' M Yudina
- Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603022, Russia
| | - Vladimir S Sukhov
- Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603022, Russia.
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4
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Ladeynova M, Kuznetsova D, Mudrilov M, Vodeneev V. Integration of Electrical Signals and Phytohormones in the Control of Systemic Response. Int J Mol Sci 2023; 24. [PMID: 36614284 DOI: 10.3390/ijms24010847] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/26/2022] [Accepted: 12/28/2022] [Indexed: 01/05/2023] Open
Abstract
Plants are constantly exposed to environmental stresses. Local stimuli sensed by one part of a plant are translated into long-distance signals that can influence the activities in distant tissues. Changes in levels of phytohormones in distant parts of the plant occur in response to various local stimuli. The regulation of hormone levels can be mediated by long-distance electrical signals, which are also induced by local stimulation. We consider the crosstalk between electrical signals and phytohormones and identify interaction points, as well as provide insights into the integration nodes that involve changes in pH, Ca2+ and ROS levels. This review also provides an overview of our current knowledge of how electrical signals and hormones work together to induce a systemic response.
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Sukhova E, Ratnitsyna D, Sukhov V. Simulated Analysis of Influence of Changes in H +-ATPase Activity and Membrane CO 2 Conductance on Parameters of Photosynthetic Assimilation in Leaves. Plants (Basel) 2022; 11:plants11243435. [PMID: 36559546 PMCID: PMC9783116 DOI: 10.3390/plants11243435] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2022] [Revised: 12/03/2022] [Accepted: 12/05/2022] [Indexed: 05/09/2023]
Abstract
Photosynthesis is an important process in plants which influences their development and productivity. Many factors can control the efficiency of photosynthesis, including CO2 conductance of leaf mesophyll, which affects the CO2 availability for Rubisco. It is known that electrical stress signals can decrease this conductance, and the response is probably caused by inactivation of H+-ATPase in the plasma membrane. In the current work, we analyzed the influence of both CO2 conductance in the plasma membrane, and chloroplast envelopes and H+-ATPase activity on photosynthetic CO2 assimilation, using a two-dimensional mathematical model of photosynthesis in leaves. The model included a description of assimilation on the basis of the Farquhar-von Caemmerer-Berry model, ion transport through the plasma membrane, diffusion of CO2 in the apoplast, and transport of CO2 through the plasma membrane and chloroplast envelope. The model showed that the photosynthetic CO2 assimilation rate was mainly dependent on the plasma membrane and chloroplast envelope conductance; direct influence of the H+-ATPase activity (through changes in pH and CO2/HCO3- concentration ratio) on this rate was weak. In contrast, both changes in CO2 conductance of the plasma membrane and chloroplast envelopes and changes in the H+-ATPase activity influenced spatial heterogeneity of the CO2 assimilation on the leaf surface in the simulated two-dimensional system. These effects were also observed under simultaneous changes in the CO2 conductance of the plasma membrane and H+-ATPase activity. Qualitatively similar influence of changes in the CO2 conductance of the plasma membrane and chloroplast envelopes, and changes in the H+-ATPase activity on photosynthesis were shown for two different densities of stomata in the simulated leaf; however, lowering the density of stomata decreased the assimilation rate and increased the heterogeneity of assimilation. The results of the model analysis clarify the potential influence of H+-ATPase inactivation on photosynthesis, and can be the basis for development of new methods for remote sensing of the influence of electrical signals.
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Mudrilov M, Ladeynova M, Grinberg M, Balalaeva I, Vodeneev V. Electrical Signaling of Plants under Abiotic Stressors: Transmission of Stimulus-Specific Information. Int J Mol Sci 2021; 22:10715. [PMID: 34639056 DOI: 10.3390/ijms221910715] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/20/2021] [Accepted: 09/22/2021] [Indexed: 12/16/2022] Open
Abstract
Plants have developed complex systems of perception and signaling to adapt to changing environmental conditions. Electrical signaling is one of the most promising candidates for the regulatory mechanisms of the systemic functional response under the local action of various stimuli. Long-distance electrical signals of plants, such as action potential (AP), variation potential (VP), and systemic potential (SP), show specificities to types of inducing stimuli. The systemic response induced by a long-distance electrical signal, representing a change in the activity of a complex of molecular-physiological processes, includes a nonspecific component and a stimulus-specific component. This review discusses possible mechanisms for transmitting information about the nature of the stimulus and the formation of a specific systemic response with the participation of electrical signals induced by various abiotic factors.
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Sukhova E, Sukhov V. Electrical Signals, Plant Tolerance to Actions of Stressors, and Programmed Cell Death: Is Interaction Possible? Plants (Basel) 2021; 10:1704. [PMID: 34451749 DOI: 10.3390/plants10081704] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 01/22/2023]
Abstract
In environmental conditions, plants are affected by abiotic and biotic stressors which can be heterogenous. This means that the systemic plant adaptive responses on their actions require long-distance stress signals including electrical signals (ESs). ESs are based on transient changes in the activities of ion channels and H+-ATP-ase in the plasma membrane. They influence numerous physiological processes, including gene expression, phytohormone synthesis, photosynthesis, respiration, phloem mass flow, ATP content, and many others. It is considered that these changes increase plant tolerance to the action of stressors; the effect can be related to stimulation of damages of specific molecular structures. In this review, we hypothesize that programmed cell death (PCD) in plant cells can be interconnected with ESs. There are the following points supporting this hypothesis. (i) Propagation of ESs can be related to ROS waves; these waves are a probable mechanism of PCD initiation. (ii) ESs induce the inactivation of photosynthetic dark reactions and activation of respiration. Both responses can also produce ROS and, probably, induce PCD. (iii) ESs stimulate the synthesis of stress phytohormones (e.g., jasmonic acid, salicylic acid, and ethylene) which are known to contribute to the induction of PCD. (iv) Generation of ESs accompanies K+ efflux from the cytoplasm that is also a mechanism of induction of PCD. Our review argues for the possibility of PCD induction by electrical signals and shows some directions of future investigations in the field.
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Ul Haq A, Carotenuto F, De Matteis F, Prosposito P, Francini R, Teodori L, Pasquo A, Di Nardo P. Intrinsically Conductive Polymers for Striated Cardiac Muscle Repair. Int J Mol Sci 2021; 22:8550. [PMID: 34445255 PMCID: PMC8395236 DOI: 10.3390/ijms22168550] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Accepted: 08/05/2021] [Indexed: 12/12/2022] Open
Abstract
One of the most important features of striated cardiac muscle is the excitability that turns on the excitation-contraction coupling cycle, resulting in the heart blood pumping function. The function of the heart pump may be impaired by events such as myocardial infarction, the consequence of coronary artery thrombosis due to blood clots or plaques. This results in the death of billions of cardiomyocytes, the formation of scar tissue, and consequently impaired contractility. A whole heart transplant remains the gold standard so far and the current pharmacological approaches tend to stop further myocardium deterioration, but this is not a long-term solution. Electrically conductive, scaffold-based cardiac tissue engineering provides a promising solution to repair the injured myocardium. The non-conductive component of the scaffold provides a biocompatible microenvironment to the cultured cells while the conductive component improves intercellular coupling as well as electrical signal propagation through the scar tissue when implanted at the infarcted site. The in vivo electrical coupling of the cells leads to a better regeneration of the infarcted myocardium, reducing arrhythmias, QRS/QT intervals, and scar size and promoting cardiac cell maturation. This review presents the emerging applications of intrinsically conductive polymers in cardiac tissue engineering to repair post-ischemic myocardial insult.
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Affiliation(s)
- Arsalan Ul Haq
- Dipartimento di Scienze Cliniche e Medicina Traslazionale, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy;
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
| | - Felicia Carotenuto
- Dipartimento di Scienze Cliniche e Medicina Traslazionale, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy;
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- Department of Fusion and Technologies for Nuclear Safety and Security, Diagnostic and Metrology (FSN-TECFIS-DIM), ENEA, CR Frascati, 00044 Rome, Italy;
| | - Fabio De Matteis
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- Dipartimento di Ingegneria Industriale, Università degli Studi di Roma “Tor Vergata”, Via del Politecnico, 00133 Roma, Italy
| | - Paolo Prosposito
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- Dipartimento di Ingegneria Industriale, Università degli Studi di Roma “Tor Vergata”, Via del Politecnico, 00133 Roma, Italy
| | - Roberto Francini
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- Dipartimento di Ingegneria Industriale, Università degli Studi di Roma “Tor Vergata”, Via del Politecnico, 00133 Roma, Italy
| | - Laura Teodori
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- Department of Fusion and Technologies for Nuclear Safety and Security, Diagnostic and Metrology (FSN-TECFIS-DIM), ENEA, CR Frascati, 00044 Rome, Italy;
| | - Alessandra Pasquo
- Department of Fusion and Technologies for Nuclear Safety and Security, Diagnostic and Metrology (FSN-TECFIS-DIM), ENEA, CR Frascati, 00044 Rome, Italy;
| | - Paolo Di Nardo
- Dipartimento di Scienze Cliniche e Medicina Traslazionale, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy;
- CIMER—Centro di Ricerca Interdipartimentale di Medicina Rigenerativa, Università degli Studi di Roma “Tor Vergata”, Via Montpellier 1, 00133 Rome, Italy; (F.D.M.); (P.P.); (R.F.); (L.T.)
- L.L. Levshin Institute of Cluster Oncology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
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Yudina L, Sherstneva O, Sukhova E, Grinberg M, Mysyagin S, Vodeneev V, Sukhov V. Inactivation of H +-ATPase Participates in the Influence of Variation Potential on Photosynthesis and Respiration in Peas. Plants (Basel) 2020; 9:E1585. [PMID: 33207655 PMCID: PMC7697462 DOI: 10.3390/plants9111585] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Revised: 11/14/2020] [Accepted: 11/15/2020] [Indexed: 12/11/2022]
Abstract
Local damage (e.g., burning, heating, or crushing) causes the generation and propagation of a variation potential (VP), which is a unique electrical signal in higher plants. A VP influences numerous physiological processes, with photosynthesis and respiration being important targets. VP generation is based on transient inactivation of H+-ATPase in plasma membrane. In this work, we investigated the participation of this inactivation in the development of VP-induced photosynthetic and respiratory responses. Two- to three-week-old pea seedlings (Pisum sativum L.) and their protoplasts were investigated. Photosynthesis and respiration in intact seedlings were measured using a GFS-3000 gas analyzer, Dual-PAM-100 Pulse-Amplitude-Modulation (PAM)-fluorometer, and a Dual-PAM gas-exchange Cuvette 3010-Dual. Electrical activity was measured using extracellular electrodes. The parameters of photosynthetic light reactions in protoplasts were measured using the Dual-PAM-100; photosynthesis- and respiration-related changes in O2 exchange rate were measured using an Oxygraph Plus System. We found that preliminary changes in the activity of H+-ATPase in the plasma membrane (its inactivation by sodium orthovanadate or activation by fusicoccin) influenced the amplitudes and magnitudes of VP-induced photosynthetic and respiratory responses in intact seedlings. Decreases in H+-ATPase activity (sodium orthovanadate treatment) induced fast decreases in photosynthetic activity and increases in respiration in protoplasts. Thus, our results support the effect of H+-ATPase inactivation on VP-induced photosynthetic and respiratory responses.
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Affiliation(s)
| | | | | | | | | | | | - Vladimir Sukhov
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, 603950 Nizhny Novgorod, Russia; (L.Y.); (O.S.); (E.S.); (M.G.); (S.M.); (V.V.)
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Yudina L, Sukhova E, Sherstneva O, Grinberg M, Ladeynova M, Vodeneev V, Sukhov V. Exogenous Abscisic Acid Can Influence Photosynthetic Processes in Peas through a Decrease in Activity of H +-ATP-ase in the Plasma Membrane. Biology (Basel) 2020; 9:E324. [PMID: 33020382 DOI: 10.3390/biology9100324] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 10/01/2020] [Accepted: 10/02/2020] [Indexed: 12/22/2022]
Abstract
Simple Summary Numerous stressors (drought, low and high temperatures, mechanical damages, etc.) act on plants under environmental conditions, suppressing their physiological processes (in particular, photosynthesis). Abscisic acid (ABA) is an important hormone, which participates in increasing plant tolerance to the action of stressors; as a result, treatment by exogenous ABA is a perspective way of regulating the tolerance in agriculture. We investigated the influence of ABA spraying on photosynthetic processes, as well as on their heat tolerance and their regulation by electrical signals propagating after local burning and modifying photosynthesis. It was shown that ABA spraying decreased photosynthetic activity and increased photosynthetic heat tolerance; additionally, the ABA treatment weakened the influence of electrical signals on photosynthesis. We revealed that these responses could be caused by a decrease in activity of H+-ATP-ase, which is an important ion transporter in plant cell plasma membrane that supports efflux of H+ from cytoplasm. As a whole, our results show the potential influence of the ABA treatment on photosynthetic processes, which is related to a decrease in activity of H+-ATP-ase. The result can be potentially useful for development of new methods of management of plant tolerance in agriculture. Abstract Abscisic acid (ABA) is an important hormone in plants that participates in their acclimation to the action of stressors. Treatment by exogenous ABA and its synthetic analogs are a potential way of controlling the tolerance of agricultural plants; however, the mechanisms of influence of the ABA treatment on photosynthetic processes require further investigations. The aim of our work was to investigate the participation of inactivation of the plasma membrane H+-ATP-ase on the influence of ABA treatment on photosynthetic processes and their regulation by electrical signals in peas. The ABA treatment of seedlings was performed by spraying them with aqueous solutions (10−5 M). The combination of a Dual-PAM-100 PAM fluorometer and GFS-3000 infrared gas analyzer was used for photosynthetic measurements; the patch clamp system on the basis of a SliceScope Pro 2000 microscope was used for measurements of electrical activity. It was shown that the ABA treatment stimulated the cyclic electron flow around photosystem I and decreased the photosynthetic CO2 assimilation, the amplitude of burning-induced electrical signals (variation potentials), and the magnitude of photosynthetic responses relating to these signals; in contrast, treatment with exogenous ABA increased the heat tolerance of photosynthesis. An investigation of the influence of ABA treatment on the metabolic component of the resting potential showed that this treatment decreased the activity of the H+-ATP-ase in the plasma membrane. Inhibitor analysis using sodium orthovanadate demonstrated that this decrease may be a mechanism of the ABA treatment-induced changes in photosynthetic processes, their heat tolerance, and regulation by electrical signals.
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11
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Kocáb O, Jakšová J, Novák O, Petřík I, Lenobel R, Chamrád I, Pavlovič A. Jasmonate-independent regulation of digestive enzyme activity in the carnivorous butterwort Pinguicula × Tina. J Exp Bot 2020; 71:3749-3758. [PMID: 32219314 PMCID: PMC7307851 DOI: 10.1093/jxb/eraa159] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/25/2020] [Indexed: 05/18/2023]
Abstract
Carnivorous plants within the order Caryophyllales use jasmonates, a class of phytohormone, in the regulation of digestive enzyme activities. We used the carnivorous butterwort Pinguicula × Tina from the order Lamiales to investigate whether jasmonate signaling is a universal and ubiquitous signaling pathway that exists outside the order Caryophyllales. We measured the electrical signals, enzyme activities, and phytohormone tissue levels in response to prey capture. Mass spectrometry was used to identify proteins in the digestive secretion. We identified eight enzymes in the digestive secretion, many of which were previously found in other genera of carnivorous plants. Among them, alpha-amylase is unique in carnivorous plants. Enzymatic activities increased in response to prey capture; however, the tissue content of jasmonic acid and its isoleucine conjugate remained rather low in contrast to the jasmonate response to wounding. Enzyme activities did not increase in response to the exogenous application of jasmonic acid or coronatine. Whereas similar digestive enzymes were co-opted from plant defense mechanisms among carnivorous plants, the mode of their regulation differs. The butterwort has not co-opted jasmonate signaling for the induction of enzyme activities in response to prey capture. Moreover, the presence of alpha-amylase in digestive fluid of P. × Tina, which has not been found in other genera of carnivorous plants, might indicate that non-defense-related genes have also been co-opted for carnivory.
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Affiliation(s)
- Ondřej Kocáb
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Jana Jakšová
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Ondřej Novák
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences and Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc , Czech Republic
| | - Ivan Petřík
- Laboratory of Growth Regulators, Institute of Experimental Botany, The Czech Academy of Sciences and Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc , Czech Republic
| | - René Lenobel
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Ivo Chamrád
- Department of Protein Biochemistry and Proteomics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
| | - Andrej Pavlovič
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic
- Correspondence:
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12
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Huber AE, Melcher PJ, Piñeros MA, Setter TL, Bauerle TL. Signal coordination before, during and after stomatal closure in response to drought stress. New Phytol 2019; 224:675-688. [PMID: 31364171 DOI: 10.1111/nph.16082] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 07/22/2019] [Indexed: 05/27/2023]
Abstract
Signal coordination in response to changes in water availability remains unclear, as does the role of embolism events in signaling drought stress. Sunflowers were exposed to two drought treatments of varying intensity while simultaneously monitoring changes in stomatal conductance, acoustic emissions (AE), turgor pressure, surface-level electrical potential, organ-level water potential and leaf abscisic acid (ABA) concentration. Leaf, stem and root xylem vulnerability to embolism were measured with the single vessel injection technique. In both drought treatments, it was found that AE events and turgor changes preceded the onset of stomatal closure, whereas electrical surface potentials shifted concurrently with stomatal closure. Leaf-level ABA concentration did not change until after stomata were closed. Roots and petioles were equally vulnerable to drought stress based on the single vessel injection technique. However, anatomical analysis of the xylem indicated that the increased AE events were not a result of xylem embolism formation. Additionally, roots and stems never reached a xylem pressure threshold that would initiate runaway embolism throughout the entire experiment. It is concluded that stomatal closure was not embolism-driven, but, rather, that onset of stomatal closure was most closely correlated with the hydraulic signal from changes in leaf turgor.
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Affiliation(s)
- Annika E Huber
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, NY, USA
| | - Peter J Melcher
- Biology Department, Center for Natural Sciences, Ithaca College, Ithaca, NY, 14850, NY, USA
| | - Miguel A Piñeros
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, NY, USA
- Robert W. Holley Center for Agriculture and Health, USDA-ARS, Cornell University, Ithaca, NY, 14853, NY, USA
| | - Tim L Setter
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, NY, USA
| | - Taryn L Bauerle
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, NY, USA
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Pavlovič A, Mithöfer A. Jasmonate signalling in carnivorous plants: copycat of plant defence mechanisms. J Exp Bot 2019; 70:3379-3389. [PMID: 31120525 DOI: 10.1093/jxb/erz188] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Accepted: 04/09/2019] [Indexed: 05/09/2023]
Abstract
The lipid-derived jasmonate phytohormones (JAs) regulate a wide spectrum of physiological processes in plants such as growth, development, tolerance to abiotic stresses, and defence against pathogen infection and insect attack. Recently, a new role for JAs has been revealed in carnivorous plants. In these specialized plants, JAs can induce the formation of digestive cavities and regulate enzyme production in response to different stimuli from caught prey. Appearing to be a new function for JAs in plants, a closer look reveals that the signalling pathways involved resemble known signalling pathways from plant defence mechanisms. Moreover, the digestion-related secretome of carnivorous plants is composed of many pathogenesis-related (PR) proteins and low molecular weight compounds, indicating that the plant carnivory syndrome is related to and has evolved from plant defence mechanisms. This review describes the similarities between defence and carnivory. It further describes how, after recognition of caught insects, JAs enable the carnivorous plants to digest and benefit from the prey. In addition, a causal connection between electrical and jasmonate signalling is discussed.
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Affiliation(s)
- Andrej Pavlovič
- Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Faculty of Science, Palacký University, Šlechtitelů, CZ, Olomouc, Czech Republic
| | - Axel Mithöfer
- Research Group Plant Defense Physiology, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße, Jena, Germany
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14
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Evans MJ, Morris RJ. Chemical agents transported by xylem mass flow propagate variation potentials. Plant J 2017; 91:1029-1037. [PMID: 28656705 PMCID: PMC5601289 DOI: 10.1111/tpj.13624] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2017] [Revised: 06/19/2017] [Accepted: 06/21/2017] [Indexed: 05/20/2023]
Abstract
Long-distance signalling is important for coordinating plant responses to the environment. Variation potentials (VPs) are a type of long-distance electrical signal that are generated in plants in response to wounding or flaming. Unlike self-propagating action potentials, VPs can be measured beyond regions of dead or chemically treated tissue that block signal generation, suggesting a different mode of propagation. Two alternative propagation mechanisms have been proposed: movement of a chemical agent and a pressure wave through the vasculature. Variants of these two signalling mechanisms have been suggested. Here, we use simple models of the underlying physical processes to evaluate and compare these predictions against independent data. Our models suggest that chemical diffusion and pressure waves are unlikely to capture existing data with parameters that are known from other sources. The previously discarded hypothesis of mass flow in the xylem transporting a chemical agent, however, is able to reproduce experimental propagation speeds for VPs. We therefore suggest that chemical agents transported by mass flow within the xylem are more likely than a pressure wave or chemical diffusion as a VP propagation mechanism. Understanding this mode of long-distance signalling within plants is important for unravelling how plants coordinate physiological responses via cell-to-cell communication.
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Affiliation(s)
- Matthew J. Evans
- Computational and Systems BiologyCrop GeneticsJohn Innes CentreColney LaneNorwichNR4 7UHUK
| | - Richard J. Morris
- Computational and Systems BiologyCrop GeneticsJohn Innes CentreColney LaneNorwichNR4 7UHUK
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15
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Mithöfer A. What Darwin only divined: unraveling the hierarchy of signaling events upon prey catch in carnivorous sundew plants. New Phytol 2017; 213:1564-1566. [PMID: 28164339 DOI: 10.1111/nph.14463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Axel Mithöfer
- Department of Bioorganic Chemistry, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745, Jena, Germany
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16
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Tahvildari R, Beamish E, Briggs K, Chagnon-Lessard S, Sohi AN, Han S, Watts B, Tabard-Cossa V, Godin M. Manipulating Electrical and Fluidic Access in Integrated Nanopore-Microfluidic Arrays Using Microvalves. Small 2017; 13:1602601. [PMID: 28026148 DOI: 10.1002/smll.201602601] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 10/06/2016] [Indexed: 06/06/2023]
Abstract
On-chip microvalves regulate electrical and fluidic access to an array of nanopores integrated within microfluidic networks. This configuration allows for on-chip sequestration of biomolecular samples in various flow channels and analysis by independent nanopores.
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Affiliation(s)
- Radin Tahvildari
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Eric Beamish
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Kyle Briggs
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | | | - Ali Najafi Sohi
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Shuo Han
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | - Benjamin Watts
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
| | | | - Michel Godin
- Department of Physics, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
- Department of Mechanical Engineering, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
- Ottawa-Carleton Institute for Biomedical Engineering, University of Ottawa, Ottawa, Ontario, K1N 6N5, Canada
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17
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Lautner S, Stummer M, Matyssek R, Fromm J, Grams TEE. Involvement of respiratory processes in the transient knockout of net CO2 uptake in Mimosa pudica upon heat stimulation. Plant Cell Environ 2014; 37:254-260. [PMID: 23763645 DOI: 10.1111/pce.12150] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Revised: 05/31/2013] [Accepted: 06/03/2013] [Indexed: 06/02/2023]
Abstract
Leaf photosynthesis of the sensitive plant Mimosa pudica displays a transient knockout in response to electrical signals induced by heat stimulation. This study aims at clarifying the underlying mechanisms, in particular, the involvement of respiration. To this end, leaf gas exchange and light reactions of photosynthesis were assessed under atmospheric conditions largely eliminating photorespiration by either elevated atmospheric CO2 or lowered O2 concentration (i.e. 2000 μmol mol(-1) or 1%, respectively). In addition, leaf gas exchange was studied in the absence of light. Under darkness, heat stimulation caused a transient increase of respiratory CO2 release simultaneously with stomatal opening, hence reflecting direct involvement of respiratory stimulation in the drop of the net CO2 uptake rate. However, persistence of the transient decline in net CO2 uptake rate under illumination and elevated CO2 or 1% O2 makes it unlikely that photorespiration is the metabolic origin of the respiratory CO2 release. In conclusion, the transient knockout of net CO2 uptake is at least partially attributed to an increased CO2 release through mitochondrial respiration as stimulated by electrical signals. Putative CO2 limitation of Rubisco due to decreased activity of carbonic anhydrase was ruled out as the photosynthesis effect was not prevented by elevated CO2 .
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Affiliation(s)
- Silke Lautner
- Institute for Wood Biology, Center of Wood Sciences, Universität Hamburg, Leuschnerstrasse 91d, 21031, Hamburg, Germany
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18
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Gil PM, Gurovich L, Schaffer B, García N, Iturriaga R. Electrical signaling, stomatal conductance, ABA and ethylene content in avocado trees in response to root hypoxia. Plant Signal Behav 2009; 4:100-8. [PMID: 19649181 PMCID: PMC2637490 DOI: 10.4161/psb.4.2.7872] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/26/2008] [Accepted: 01/16/2009] [Indexed: 05/18/2023]
Abstract
Avocado (Persea americana Mill.) trees are among the most sensitive of fruit tree species to root hypoxia as a result of flooded or poorly drained soil. Similar to drought stress, an early physiological response to root hypoxia in avocado is a reduction of stomatal conductance. It has been previously determined in avocado trees that an extracellular electrical signal between the base of stem and leaves is produced and related to reductions in stomatal conductance in response to drought stress. The current study was designed to determine if changes in the extracellular electrical potential between the base of the stem and leaves in avocado trees could also be detected in response to short-term (min) or long-term (days) root hypoxia, and if these signals could be related to stomatal conductance (gs), root and leaf ABA and ACC concentrations, ethylene emission from leaves and leaf abscission. In contrast to previous observations for drought-stressed trees, short-term or long-term root hypoxia did not stimulate an electrical potential difference between the base of the stem and leaves. Short-term hypoxia did not result in a significant decrease in gs compared with plants in the control treatment, and no differences in ABA concentration were found between plants subjected to hypoxia and control plants. Long-term hypoxia in the root zone resulted in a significant decrease in gs, increased leaf ethylene and increased leaf abscission. The results indicate that for avocado trees exposed to root hypoxia, electrical signals do not appear to be the primary root-to-shoot communication mechanism involved in signaling for stomatal closure as a result of hypoxia in the root zone.
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Affiliation(s)
- Pilar M Gil
- Departamento de Fruticultura y Enología, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Casilla, Santiago, Chile.
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McCaig C. Electrical control of cell behaviour and wound healing. GMS Krankenhhyg Interdiszip 2008; 3:Doc03. [PMID: 20204105 PMCID: PMC2831526] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- Colin McCaig
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, Scotland,*To whom correspondence should be addressed: Colin McCaig, Institute of Medical Sciences, University of Aberdeen, Aberdeen, AB25 2ZD, Scotland, E-mail:
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