1
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Das S, Mussel M. Characterizing Oscillatory and Excitability Regimes in a Protein-Free Lipid Membrane. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2023; 39:5752-5760. [PMID: 37058369 DOI: 10.1021/acs.langmuir.2c03495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Observations of electric potential oscillations in artificial lipid bilayers near the order-disorder transition indicate the existence of a stable limit cycle and, therefore, the possibility of producing excitable signals close to the bifurcation. We present a theoretical investigation of membrane oscillatory and excitability regimes induced by an increase in ion permeability at the order-disorder transition. The model accounts for the coupled effects of state-dependent permeability, membrane charge density, and hydrogen ion adsorption. A bifurcation diagram shows a transition between fixed-point and limit cycle solutions, enabling both oscillatory and excitability responses at different values of the acid association parameter. Oscillations are identified in terms of the membrane state, electric potential difference, and ion concentration near the membrane. The emerging voltage and time scales agree with measurements. Excitability is demonstrated by applying an external electric current stimulus, and the emerging signals display a threshold response and the appearance of repetitive signals upon using a long-lasting stimulus. The approach highlights the important role of the order-disorder transition, enabling membrane excitability in the absence of specialized proteins.
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Affiliation(s)
- Sandip Das
- Department of Physics, University of Haifa, 199 Aba Khoushy Avenue, Haifa 3498838, Israel
| | - Matan Mussel
- Department of Physics, University of Haifa, 199 Aba Khoushy Avenue, Haifa 3498838, Israel
- Center for Biophysics and Quantitative Biology, University of Haifa, 199 Aba Khoushy Avenue, Haifa 3498838, Israel
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2
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Pupkis V, Lapeikaite I, Kavaliauskas J, Trebacz K, Kisnieriene V. Certain calcium channel inhibitors exhibit a number of secondary effects on the physiological properties in Nitellopsis obtusa: a voltage clamp approach. FUNCTIONAL PLANT BIOLOGY : FPB 2023; 50:195-205. [PMID: 36318873 DOI: 10.1071/fp22106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
An unsolved problem of contemporary plant electrophysiology is the identity of Ca2+ channels responsible for the initiation of the action potential. We took a pharmacological approach and applied several Ca2+ channel blockers (verapamil, tetrandrine, and NED-19) on a Characean (Nitellopsis obtusa ) algae model system. The impact of the selected pharmaceuticals on the parameters of excitation transients of a single cell was analysed employing the two-electrode voltage clamp technique. It was revealed that tetrandrine exerted no effect, while both verapamil and NED-19 prolonged activation and inactivation durations of the excitatory Cl- current. NED-19 also significantly depolarised the excitation threshold membrane potential and shifted Ca2+ current reversal potential. Thus, NED-19 most specifically targeted Ca2+ channels. A viability assay paired with observations of cytoplasmic streaming revealed that verapamil affected not only Ca2+ channels but also exhibited non-specific effects, which eventually lead to cell death. Since many potential Ca2+ channel blockers exert additional undesirable non-specific effects, our study underlines the necessity to search for new more specific modulators of plant Ca2+ transport systems.
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Affiliation(s)
- Vilmantas Pupkis
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, 7 Sauletekio Avenue, 10257 Vilnius, Lithuania
| | - Indre Lapeikaite
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, 7 Sauletekio Avenue, 10257 Vilnius, Lithuania
| | - Julius Kavaliauskas
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, 7 Sauletekio Avenue, 10257 Vilnius, Lithuania
| | - Kazimierz Trebacz
- Department of Plant Physiology and Biophysics, Institute of Biological Sciences, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, 19 Akademicka, 20-033 Lublin, Poland
| | - Vilma Kisnieriene
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, 7 Sauletekio Avenue, 10257 Vilnius, Lithuania
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3
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Brownlee C. Plant physiology: Anatomy of a plant action potential. Curr Biol 2022; 32:R1000-R1002. [PMID: 36220083 DOI: 10.1016/j.cub.2022.08.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The Venus flytrap possesses modified leaves that can snap shut fast enough to catch a fly. A new study identifies the major components of the toolkit that allows the flytrap to fire action potentials, illustrating how different ion channels and transporters are recruited to give rise to this unique plant behavioural response.
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Affiliation(s)
- Colin Brownlee
- Marine Biological Association, the Laboratory, Citadel Hill, Plymouth, UK.
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4
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Scherzer S, Böhm J, Huang S, Iosip AL, Kreuzer I, Becker D, Heckmann M, Al-Rasheid KAS, Dreyer I, Hedrich R. A unique inventory of ion transporters poises the Venus flytrap to fast-propagating action potentials and calcium waves. Curr Biol 2022; 32:4255-4263.e5. [PMID: 36087579 DOI: 10.1016/j.cub.2022.08.051] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 06/20/2022] [Accepted: 08/17/2022] [Indexed: 12/14/2022]
Abstract
Since the 19th century, it has been known that the carnivorous Venus flytrap is electrically excitable. Nevertheless, the mechanism and the molecular entities of the flytrap action potential (AP) remain unknown. When entering the electrically excitable stage, the trap expressed a characteristic inventory of ion transporters, among which the increase in glutamate receptor GLR3.6 RNA was most pronounced. Trigger hair stimulation or glutamate application evoked an AP and a cytoplasmic Ca2+ transient that both propagated at the same speed from the site of induction along the entire trap lobe surface. A priming Ca2+ moiety entering the cytoplasm in the context of the AP was further potentiated by an organelle-localized calcium-induced calcium release (CICR)-like system prolonging the Ca2+ signal. While the Ca2+ transient persisted, SKOR K+ channels and AHA H+-ATPases repolarized the AP already. By counting the number of APs and long-lasting Ca2+ transients, the trap directs the different steps in the carnivorous plant's hunting cycle. VIDEO ABSTRACT.
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Affiliation(s)
- Sönke Scherzer
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany.
| | - Jennifer Böhm
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany
| | - Shouguang Huang
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany
| | - Anda L Iosip
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany
| | - Ines Kreuzer
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany
| | - Dirk Becker
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany
| | - Manfred Heckmann
- Department of Neurophysiology, Institute of Physiology, Wuerzburg University, Röntgenring 9, 97070 Wuerzburg, Germany
| | - Khaled A S Al-Rasheid
- Zoology Department, College of Science, King Saud University, Riyadh 11451, Saudi Arabia
| | - Ingo Dreyer
- Center of Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, 2 Norte 685, Talca 3460000, Chile
| | - Rainer Hedrich
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Wuerzburg University, Julius-von-Sachs-Platz 2, 97070 Wuerzburg, Germany.
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Kisnieriene V, Trębacz K, Pupkis V, Koselski M, Lapeikaite I. Evolution of long-distance signalling upon plant terrestrialization: comparison of action potentials in Characean algae and liverworts. ANNALS OF BOTANY 2022; 130:457-475. [PMID: 35913486 PMCID: PMC9510943 DOI: 10.1093/aob/mcac098] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 07/27/2022] [Indexed: 06/15/2023]
Abstract
BACKGROUND In this review, we summarize data concerning action potentials (APs) - long-distance electrical signals in Characean algae and liverworts. These lineages are key in understanding the mechanisms of plant terrestrialization. Liverworts are postulated to be pioneer land plants, whereas aquatic charophytes are considered the closest relatives to land plants. The drastic change of the habitat was coupled with the adaptation of signalling systems to the new environment. SCOPE APs fulfil the 'all-or-nothing' law, exhibit refractory periods and propagate with a uniform velocity. Their ion mechanism in the algae and liverworts consists of a Ca2+ influx (from external and internal stores) followed by/coincident with a Cl- efflux, which both evoke the membrane potential depolarization, and a K+ efflux leading to repolarization. The molecular identity of ion channels responsible for these fluxes remains unknown. Publication of the Chara braunii and Marchantia polymorpha genomes opened up new possibilities for studying the molecular basis of APs. Here we present the list of genes which can participate in AP electrogenesis. We also point out the differences between these plant species, e.g. the absence of Ca2+-permeable glutamate receptors (GLRs) and Cl--permeable SLAC1 channel homologues in the Chara genome. Both these channels play a vital role in long-distance signalling in liverworts and vascular plants. Among the common properties of APs in liverworts and higher plants is their duration (dozens of seconds) and the speed of propagation (mm s-1), which are much slower than in the algae (seconds, and dozens of mm s-1, respectively). CONCLUSIONS Future studies with combined application of electrophysiological and molecular techniques should unravel the ion channel proteins responsible for AP generation, their regulation and transduction of those signals to physiological responses. This should also help to understand the adaptation of the signalling systems to the land environment and further evolution of APs in vascular plants.
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Affiliation(s)
| | | | - Vilmantas Pupkis
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Saulėtekio Ave, Vilnius, Lithuania
| | - Mateusz Koselski
- Department of Plant Physiology and Biophysics, Institute of Biological Sciences, Faculty of Biology and Biotechnology, Maria Curie-Sklodowska University, Akademicka, Lublin, Poland
| | - Indre Lapeikaite
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Saulėtekio Ave, Vilnius, Lithuania
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6
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Ether anesthetics prevents touch-induced trigger hair calcium-electrical signals excite the Venus flytrap. Sci Rep 2022; 12:2851. [PMID: 35181728 PMCID: PMC8857258 DOI: 10.1038/s41598-022-06915-z] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Accepted: 02/08/2022] [Indexed: 11/08/2022] Open
Abstract
Plants do not have neurons but operate transmembrane ion channels and can get electrical excited by physical and chemical clues. Among them the Venus flytrap is characterized by its peculiar hapto-electric signaling. When insects collide with trigger hairs emerging the trap inner surface, the mechanical stimulus within the mechanosensory organ is translated into a calcium signal and an action potential (AP). Here we asked how the Ca2+ wave and AP is initiated in the trigger hair and how it is feed into systemic trap calcium-electrical networks. When Dionaea muscipula trigger hairs matures and develop hapto-electric excitability the mechanosensitive anion channel DmMSL10/FLYC1 and voltage dependent SKOR type Shaker K+ channel are expressed in the sheering stress sensitive podium. The podium of the trigger hair is interface to the flytrap's prey capture and processing networks. In the excitable state touch stimulation of the trigger hair evokes a rise in the podium Ca2+ first and before the calcium signal together with an action potential travel all over the trap surface. In search for podium ion channels and pumps mediating touch induced Ca2+ transients, we, in mature trigger hairs firing fast Ca2+ signals and APs, found OSCA1.7 and GLR3.6 type Ca2+ channels and ACA2/10 Ca2+ pumps specifically expressed in the podium. Like trigger hair stimulation, glutamate application to the trap directly evoked a propagating Ca2+ and electrical event. Given that anesthetics affect K+ channels and glutamate receptors in the animal system we exposed flytraps to an ether atmosphere. As result propagation of touch and glutamate induced Ca2+ and AP long-distance signaling got suppressed, while the trap completely recovered excitability when ether was replaced by fresh air. In line with ether targeting a calcium channel addressing a Ca2+ activated anion channel the AP amplitude declined before the electrical signal ceased completely. Ether in the mechanosensory organ did neither prevent the touch induction of a calcium signal nor this post stimulus decay. This finding indicates that ether prevents the touch activated, glr3.6 expressing base of the trigger hair to excite the capture organ.
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7
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Dreyer I. Nutrient cycling is an important mechanism for homeostasis in plant cells. PLANT PHYSIOLOGY 2021; 187:2246-2261. [PMID: 34890457 PMCID: PMC8644529 DOI: 10.1093/plphys/kiab217] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 04/23/2021] [Indexed: 05/02/2023]
Abstract
Homeostasis in living cells refers to the steady state of internal, physical, and chemical conditions. It is sustained by self-regulation of the dynamic cellular system. To gain insight into the homeostatic mechanisms that maintain cytosolic nutrient concentrations in plant cells within a homeostatic range, we performed computational cell biology experiments. We mathematically modeled membrane transporter systems and simulated their dynamics. Detailed analyses of 'what-if' scenarios demonstrated that a single transporter type for a nutrient, irrespective of whether it is a channel or a cotransporter, is not sufficient to calibrate a desired cytosolic concentration. A cell cannot flexibly react to different external conditions. Rather, at least two different transporter types for the same nutrient, which are energized differently, are required. The gain of flexibility in adjusting a cytosolic concentration was accompanied by the establishment of energy-consuming cycles at the membrane, suggesting that these putatively "futile" cycles are not as futile as they appear. Accounting for the complex interplay of transporter networks at the cellular level may help design strategies for increasing nutrient use efficiency of crop plants.
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Affiliation(s)
- Ingo Dreyer
- Center of Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, Talca CL-3460000, Chile
- Author for communication:
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8
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Winlow W, Johnson AS. Nerve Impulses Have Three Interdependent Functions: Communication, Modulation, and Computation. Bioelectricity 2021. [DOI: 10.1089/bioe.2021.0001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- William Winlow
- Dipartimento di Biologia, Università degli Studi di Napoli, Federico II, Napoli, Italia
- Institute of Ageing and Chronic Diseases, University of Liverpool, Liverpool, United Kingdom
| | - Andrew S. Johnson
- Dipartimento di Biologia, Università degli Studi di Napoli, Federico II, Napoli, Italia
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9
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Li JH, Fan LF, Zhao DJ, Zhou Q, Yao JP, Wang ZY, Huang L. Plant electrical signals: A multidisciplinary challenge. JOURNAL OF PLANT PHYSIOLOGY 2021; 261:153418. [PMID: 33887526 DOI: 10.1016/j.jplph.2021.153418] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 04/06/2021] [Accepted: 04/06/2021] [Indexed: 05/15/2023]
Abstract
Plant electrical signals, an early event in the plant-stimulus interaction, rapidly transmit information generated by the stimulus to other organs, and even the whole plant, to promote the corresponding response and trigger a regulatory cascade. In recent years, many promising state-of-the-art technologies applicable to study plant electrophysiology have emerged. Research focused on expression of genes associated with electrical signals has also proliferated. We propose that it is appropriate for plant electrical signals to be considered in the form of a "plant electrophysiological phenotype". This review synthesizes research on plant electrical signals from a novel, interdisciplinary perspective, which is needed to improve the efficient aggregation and use of plant electrical signal data and to expedite interpretation of plant electrical signals.
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Affiliation(s)
- Jin-Hai Li
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education, Beijing, 100083, China
| | - Li-Feng Fan
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education, Beijing, 100083, China
| | - Dong-Jie Zhao
- Institute for Future (IFF), Qingdao University, Qingdao, 266071, China
| | - Qiao Zhou
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture, Beijing, 100083, China
| | - Jie-Peng Yao
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture, Beijing, 100083, China
| | - Zhong-Yi Wang
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education, Beijing, 100083, China; Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture, Beijing, 100083, China.
| | - Lan Huang
- College of Information and Electrical Engineering, China Agricultural University, Beijing, 100083, China; Key Laboratory of Agricultural Information Acquisition Technology, Ministry of Agriculture, Beijing, 100083, China.
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10
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Mallatt J, Blatt MR, Draguhn A, Robinson DG, Taiz L. Debunking a myth: plant consciousness. PROTOPLASMA 2021; 258:459-476. [PMID: 33196907 PMCID: PMC8052213 DOI: 10.1007/s00709-020-01579-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2020] [Accepted: 10/22/2020] [Indexed: 05/18/2023]
Abstract
Claims that plants have conscious experiences have increased in recent years and have received wide coverage, from the popular media to scientific journals. Such claims are misleading and have the potential to misdirect funding and governmental policy decisions. After defining basic, primary consciousness, we provide new arguments against 12 core claims made by the proponents of plant consciousness. Three important new conclusions of our study are (1) plants have not been shown to perform the proactive, anticipatory behaviors associated with consciousness, but only to sense and follow stimulus trails reactively; (2) electrophysiological signaling in plants serves immediate physiological functions rather than integrative-information processing as in nervous systems of animals, giving no indication of plant consciousness; (3) the controversial claim of classical Pavlovian learning in plants, even if correct, is irrelevant because this type of learning does not require consciousness. Finally, we present our own hypothesis, based on two logical assumptions, concerning which organisms possess consciousness. Our first assumption is that affective (emotional) consciousness is marked by an advanced capacity for operant learning about rewards and punishments. Our second assumption is that image-based conscious experience is marked by demonstrably mapped representations of the external environment within the body. Certain animals fit both of these criteria, but plants fit neither. We conclude that claims for plant consciousness are highly speculative and lack sound scientific support.
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Affiliation(s)
- Jon Mallatt
- The University of Washington WWAMI Medical Education Program at The University of Idaho, Moscow, ID 83844 USA
| | - Michael R. Blatt
- Laboratory of Plant Physiology and Biophysics, Bower Building, University of Glasgow, Glasgow, G12 8QQ UK
| | - Andreas Draguhn
- Institute for Physiology and Pathophysiology, Medical Faculty, University of Heidelberg, 69120 Heidelberg, Germany
| | - David G. Robinson
- Centre for Organismal Studies, University of Heidelberg, 69120 Heidelberg, Germany
| | - Lincoln Taiz
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Cruz, CA 95064 USA
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11
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Mallatt J, Blatt MR, Draguhn A, Robinson DG, Taiz L. Debunking a myth: plant consciousness. PROTOPLASMA 2021. [PMID: 33196907 DOI: 10.1007/s00709-026-01579-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Claims that plants have conscious experiences have increased in recent years and have received wide coverage, from the popular media to scientific journals. Such claims are misleading and have the potential to misdirect funding and governmental policy decisions. After defining basic, primary consciousness, we provide new arguments against 12 core claims made by the proponents of plant consciousness. Three important new conclusions of our study are (1) plants have not been shown to perform the proactive, anticipatory behaviors associated with consciousness, but only to sense and follow stimulus trails reactively; (2) electrophysiological signaling in plants serves immediate physiological functions rather than integrative-information processing as in nervous systems of animals, giving no indication of plant consciousness; (3) the controversial claim of classical Pavlovian learning in plants, even if correct, is irrelevant because this type of learning does not require consciousness. Finally, we present our own hypothesis, based on two logical assumptions, concerning which organisms possess consciousness. Our first assumption is that affective (emotional) consciousness is marked by an advanced capacity for operant learning about rewards and punishments. Our second assumption is that image-based conscious experience is marked by demonstrably mapped representations of the external environment within the body. Certain animals fit both of these criteria, but plants fit neither. We conclude that claims for plant consciousness are highly speculative and lack sound scientific support.
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Affiliation(s)
- Jon Mallatt
- The University of Washington WWAMI Medical Education Program at The University of Idaho, Moscow, ID, 83844, USA.
| | - Michael R Blatt
- Laboratory of Plant Physiology and Biophysics, Bower Building, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Andreas Draguhn
- Institute for Physiology and Pathophysiology, Medical Faculty, University of Heidelberg, 69120, Heidelberg, Germany
| | - David G Robinson
- Centre for Organismal Studies, University of Heidelberg, 69120, Heidelberg, Germany
| | - Lincoln Taiz
- Department of Molecular, Cellular, and Developmental Biology, University of California, Santa Cruz, CA, 95064, USA
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12
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Koselski M, Pupkis V, Hashimoto K, Lapeikaite I, Hanaka A, Wasko P, Plukaite E, Kuchitsu K, Kisnieriene V, Trebacz K. Impact of Mammalian Two-Pore Channel Inhibitors on Long-Distance Electrical Signals in the Characean Macroalga Nitellopsis obtusa and the Early Terrestrial Liverwort Marchantia polymorpha. PLANTS 2021; 10:plants10040647. [PMID: 33805421 PMCID: PMC8067100 DOI: 10.3390/plants10040647] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 03/25/2021] [Accepted: 03/25/2021] [Indexed: 11/16/2022]
Abstract
Inhibitors of human two-pore channels (TPC1 and TPC2), i.e., verapamil, tetrandrine, and NED-19, are promising medicines used in treatment of serious diseases. In the present study, the impact of these substances on action potentials (APs) and vacuolar channel activity was examined in the aquatic characean algae Nitellopsis obtusa and in the terrestrial liverwort Marchantia polymorpha. In both plant species, verapamil (20-300 µM) caused reduction of AP amplitudes, indicating impaired Ca2+ transport. In N. obtusa, it depolarized the AP excitation threshold and resting potential and prolonged AP duration. In isolated vacuoles of M. polymorpha, verapamil caused a reduction of the open probability of slow vacuolar SV/TPC channels but had almost no effect on K+ channels in the tonoplast of N. obtusa. In both species, tetrandrine (20-100 µM) evoked a pleiotropic effect: reduction of resting potential and AP amplitudes and prolongation of AP repolarization phases, especially in M. polymorpha, but it did not alter vacuolar SV/TPC activity. NED-19 (75 µM) caused both specific and unspecific effects on N. obtusa APs. In M. polymorpha, NED-19 increased the duration of repolarization. However, no inhibition of SV/TPC channels was observed in Marchantia vacuoles, but an increase in open probability and channel flickering. The results indicate an effect on Ca2+ -permeable channels governing plant excitation.
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Affiliation(s)
- Mateusz Koselski
- Department of Plant Physiology and Biophysics, Faculty of Biology and Biotechnology, Institute of Biological Sciences, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland; (M.K.); (A.H.); (P.W.)
| | - Vilmantas Pupkis
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Sauletekio av. 7, LT-10257 Vilnius, Lithuania; (V.P.); (I.L.); (E.P.)
| | - Kenji Hashimoto
- Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba 278-8510, Japan; (K.H.); (K.K.)
| | - Indre Lapeikaite
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Sauletekio av. 7, LT-10257 Vilnius, Lithuania; (V.P.); (I.L.); (E.P.)
| | - Agnieszka Hanaka
- Department of Plant Physiology and Biophysics, Faculty of Biology and Biotechnology, Institute of Biological Sciences, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland; (M.K.); (A.H.); (P.W.)
| | - Piotr Wasko
- Department of Plant Physiology and Biophysics, Faculty of Biology and Biotechnology, Institute of Biological Sciences, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland; (M.K.); (A.H.); (P.W.)
| | - Egle Plukaite
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Sauletekio av. 7, LT-10257 Vilnius, Lithuania; (V.P.); (I.L.); (E.P.)
| | - Kazuyuki Kuchitsu
- Department of Applied Biological Science, Tokyo University of Science, Noda, Chiba 278-8510, Japan; (K.H.); (K.K.)
| | - Vilma Kisnieriene
- Department of Neurobiology and Biophysics, Institute of Biosciences, Life Sciences Center, Vilnius University, Sauletekio av. 7, LT-10257 Vilnius, Lithuania; (V.P.); (I.L.); (E.P.)
- Correspondence: (V.K.); (K.T.)
| | - Kazimierz Trebacz
- Department of Plant Physiology and Biophysics, Faculty of Biology and Biotechnology, Institute of Biological Sciences, Maria Curie-Sklodowska University, Akademicka 19, 20-033 Lublin, Poland; (M.K.); (A.H.); (P.W.)
- Correspondence: (V.K.); (K.T.)
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13
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Procko C, Murthy S, Keenan WT, Mousavi SAR, Dabi T, Coombs A, Procko E, Baird L, Patapoutian A, Chory J. Stretch-activated ion channels identified in the touch-sensitive structures of carnivorous Droseraceae plants. eLife 2021; 10:e64250. [PMID: 33724187 PMCID: PMC7963481 DOI: 10.7554/elife.64250] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/18/2021] [Indexed: 12/11/2022] Open
Abstract
In response to touch, some carnivorous plants such as the Venus flytrap have evolved spectacular movements to capture animals for nutrient acquisition. However, the molecules that confer this sensitivity remain unknown. We used comparative transcriptomics to show that expression of three genes encoding homologs of the MscS-Like (MSL) and OSCA/TMEM63 family of mechanosensitive ion channels are localized to touch-sensitive trigger hairs of Venus flytrap. We focus here on the candidate with the most enriched expression in trigger hairs, the MSL homolog FLYCATCHER1 (FLYC1). We show that FLYC1 transcripts are localized to mechanosensory cells within the trigger hair, transfecting FLYC1 induces chloride-permeable stretch-activated currents in naïve cells, and transcripts coding for FLYC1 homologs are expressed in touch-sensing cells of Cape sundew, a related carnivorous plant of the Droseraceae family. Our data suggest that the mechanism of prey recognition in carnivorous Droseraceae evolved by co-opting ancestral mechanosensitive ion channels to sense touch.
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Affiliation(s)
- Carl Procko
- Plant Biology Laboratory, Salk Institute for Biological StudiesLa JollaUnited States
| | - Swetha Murthy
- Department of Neuroscience, Dorris Neuroscience Center, Scripps ResearchSan DiegoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - William T Keenan
- Department of Neuroscience, Dorris Neuroscience Center, Scripps ResearchSan DiegoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Seyed Ali Reza Mousavi
- Department of Neuroscience, Dorris Neuroscience Center, Scripps ResearchSan DiegoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Tsegaye Dabi
- Plant Biology Laboratory, Salk Institute for Biological StudiesLa JollaUnited States
| | - Adam Coombs
- Department of Neuroscience, Dorris Neuroscience Center, Scripps ResearchSan DiegoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Erik Procko
- Department of Biochemistry, University of Illinois at Urbana-ChampaignUrbanaUnited States
| | - Lisa Baird
- Department of Biology, University of San DiegoSan DiegoUnited States
| | - Ardem Patapoutian
- Department of Neuroscience, Dorris Neuroscience Center, Scripps ResearchSan DiegoUnited States
- Howard Hughes Medical InstituteChevy ChaseUnited States
| | - Joanne Chory
- Plant Biology Laboratory, Salk Institute for Biological StudiesLa JollaUnited States
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14
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Mussel M, Basser PJ, Horkay F. Ion-Induced Volume Transition in Gels and Its Role in Biology. Gels 2021; 7:20. [PMID: 33670826 PMCID: PMC8005988 DOI: 10.3390/gels7010020] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/09/2021] [Accepted: 02/11/2021] [Indexed: 12/12/2022] Open
Abstract
Incremental changes in ionic composition, solvent quality, and temperature can lead to reversible and abrupt structural changes in many synthetic and biopolymer systems. In the biological milieu, this nonlinear response is believed to play an important functional role in various biological systems, including DNA condensation, cell secretion, water flow in xylem of plants, cell resting potential, and formation of membraneless organelles. While these systems are markedly different from one another, a physicochemical framework that treats them as polyelectrolytes, provides a means to interpret experimental results and make in silico predictions. This article summarizes experimental results made on ion-induced volume phase transition in a polyelectrolyte model gel (sodium polyacrylate) and observations on the above-mentioned biological systems indicating the existence of a steep response.
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Affiliation(s)
- Matan Mussel
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
| | | | - Ferenc Horkay
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA;
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15
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Baluška F, Mancuso S. Individuality, self and sociality of vascular plants. Philos Trans R Soc Lond B Biol Sci 2021; 376:20190760. [PMID: 33550947 DOI: 10.1098/rstb.2019.0760] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Vascular plants are integrated into coherent bodies via plant-specific synaptic adhesion domains, action potentials (APs) and other means of long-distance signalling running throughout the plant bodies. Plant-specific synapses and APs are proposed to allow plants to generate their self identities having unique ways of sensing and acting as agents with their own goals guiding their future activities. Plants move their organs with a purpose and with obvious awareness of their surroundings and require APs to perform and control these movements. Self-identities allow vascular plants to act as individuals enjoying sociality via their self/non-self-recognition and kin recognition. Flowering plants emerge as cognitive and intelligent organisms when the major strategy is to attract and control their animal pollinators as well as seed dispersers by providing them with food enriched with nutritive and manipulative/addictive compounds. Their goal in interactions with animals is manipulation for reproduction, dispersal and defence. This article is part of the theme issue 'Basal cognition: multicellularity, neurons and the cognitive lens'.
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Affiliation(s)
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences, University of Florence, Florence, Italy
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16
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Iosip AL, Böhm J, Scherzer S, Al-Rasheid KAS, Dreyer I, Schultz J, Becker D, Kreuzer I, Hedrich R. The Venus flytrap trigger hair-specific potassium channel KDM1 can reestablish the K+ gradient required for hapto-electric signaling. PLoS Biol 2020; 18:e3000964. [PMID: 33296375 PMCID: PMC7725304 DOI: 10.1371/journal.pbio.3000964] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/05/2020] [Indexed: 12/18/2022] Open
Abstract
The carnivorous plant Dionaea muscipula harbors multicellular trigger hairs designed to sense mechanical stimuli upon contact with animal prey. At the base of the trigger hair, mechanosensation is transduced into an all-or-nothing action potential (AP) that spreads all over the trap, ultimately leading to trap closure and prey capture. To reveal the molecular basis for the unique functional repertoire of this mechanoresponsive plant structure, we determined the transcriptome of D. muscipula’s trigger hair. Among the genes that were found to be highly specific to the trigger hair, the Shaker-type channel KDM1 was electrophysiologically characterized as a hyperpolarization- and acid-activated K+-selective channel, thus allowing the reuptake of K+ ions into the trigger hair’s sensory cells during the hyperpolarization phase of the AP. During trap development, the increased electrical excitability of the trigger hair is associated with the transcriptional induction of KDM1. Conversely, when KDM1 is blocked by Cs+ in adult traps, the initiation of APs in response to trigger hair deflection is reduced, and trap closure is suppressed. KDM1 thus plays a dominant role in K+ homeostasis in the context of AP and turgor formation underlying the mechanosensation of trigger hair cells and thus D. muscipula’s hapto-electric signaling. Transcriptomic and electrophysiological studies of the carnivorous Venus flytrap reveal that potassium uptake via a trigger hair-specific potassium channel builds the basis for mechanosensation of likely prey and generation of an action potential that triggers closure of the trap.
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Affiliation(s)
- Anda L. Iosip
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
- Center for Computational and Theoretical Biology, University of Würzburg, Würzburg, Germany
| | - Jennifer Böhm
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
| | | | - Ingo Dreyer
- Center of Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, Talca, Chile
| | - Jörg Schultz
- Center for Computational and Theoretical Biology, University of Würzburg, Würzburg, Germany
| | - Dirk Becker
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
| | - Ines Kreuzer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
- * E-mail: (IK); (RH)
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, Würzburg, Germany
- * E-mail: (IK); (RH)
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17
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Fabiunke S, Fillafer C, Paeger A, Schneider MF. Optical studies of membrane state during action potential propagation. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 162:69-78. [DOI: 10.1016/j.pbiomolbio.2020.11.001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Revised: 10/05/2020] [Accepted: 11/13/2020] [Indexed: 10/23/2022]
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18
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Lapeikaite I, Pupkis V, Neniskis V, Ruksenas O, Kisnieriene V. Glutamate and NMDA affect cell excitability and action potential dynamics of single cell of macrophyte Nitellopsis obtusa. FUNCTIONAL PLANT BIOLOGY : FPB 2020; 47:1032-1040. [PMID: 33213696 DOI: 10.1071/fp20074] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 05/11/2020] [Indexed: 06/11/2023]
Abstract
The effect of glutamate and N-methyl-d-aspartate (NMDA) on electrical signalling - action potentials (AP) and excitation current transients - was studied in intact macrophyte Nitellopsis obtusa (Characeaen) internodal cell. Intracellular glass electrode recordings of single cell in current clamp and two-electrode voltage clamp modes indicate that glutamate (Glu, 0.1-1.0 mM) and NMDA (0.01-1.0 mM) increase electrically induced AP amplitude by hyperpolarising excitation threshold potential (Eth) and prolong AP fast repolarisation phase. Amplitude of Cl- current transient, as well as its activation and inactivation durations were also increased. Both Glu and NMDA act in a dose-dependent manner. The effect of NMDA exceeds that of Glu. Ionotropic glutamate receptor inhibitors AP-5 (NMDA-type receptors) and DNQX (AMPA/Kainate-type) have no effect on Nitellopsis cell electrical signalling per se, yet robustly inhibit excitatory effect of NMDA. This study reinforces NMDA as an active component in glutamatergic signalling at least in some plants and stresses the elaborate fine-tuning of electrical signalling.
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Affiliation(s)
- Indre Lapeikaite
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Avenue. 7, LT-10257 Vilnius, Lithuania; and Corresponding author.
| | - Vilmantas Pupkis
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Avenue. 7, LT-10257 Vilnius, Lithuania
| | - Vladas Neniskis
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Avenue. 7, LT-10257 Vilnius, Lithuania
| | - Osvaldas Ruksenas
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Avenue. 7, LT-10257 Vilnius, Lithuania
| | - Vilma Kisnieriene
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Avenue. 7, LT-10257 Vilnius, Lithuania
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19
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Fillafer C, Paeger A, Schneider MF. The living state: How cellular excitability is controlled by the thermodynamic state of the membrane. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2020; 162:57-68. [PMID: 33058943 DOI: 10.1016/j.pbiomolbio.2020.10.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 12/16/2022]
Abstract
The thermodynamic (TD) properties of biological membranes play a central role for living systems. It has been suggested, for instance, that nonlinear pulses such as action potentials (APs) can only exist if the membrane state is in vicinity of a TD transition. Herein, two membrane properties in living systems - excitability and velocity - are analyzed for a broad spectrum of conditions (temperature (T), 3D-pressure (p) and pH-dependence). Based on experimental data from Characean cells and a review of literature we predict parameter ranges in which a transition of the membrane is located (15-35°C below growth temperature; 1-3pH units below pH7; at ∼800atm) and propose the corresponding phase diagrams. The latter explain: (i) changes of AP velocity with T,p and pH.(ii) The existence and origin of two qualitatively different forms of loss of nonlinear excitability ("nerve block", anesthesia). (iii) The type and quantity of parameter changes that trigger APs. Finally, a quantitative comparison between the TD behavior of 2D-lipid model membranes with living systems is attempted. The typical shifts in transition temperature with pH and p of model membranes agree with values obtained from cell physiological measurements. Taken together, these results suggest that it is not specific molecules that control the excitability of living systems but rather the TD properties of the membrane interface. The approach as proposed herein can be extended to other quantities (membrane potential, calcium concentration, etc.) and makes falsifiable predictions, for example, that a transition exists within the specified parameter ranges in excitable cells.
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Affiliation(s)
- Christian Fillafer
- Medical and Biological Physics, Department of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227, Dortmund, Germany.
| | - Anne Paeger
- Medical and Biological Physics, Department of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227, Dortmund, Germany
| | - Matthias F Schneider
- Medical and Biological Physics, Department of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227, Dortmund, Germany
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20
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Sukhova E, Yudina L, Gromova E, Nerush V, Vodeneev V, Sukhov V. Burning-induced electrical signals influence broadband reflectance indices and water index in pea leaves. PLANT SIGNALING & BEHAVIOR 2020; 15:1737786. [PMID: 32149565 PMCID: PMC7194382 DOI: 10.1080/15592324.2020.1737786] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 02/27/2020] [Accepted: 02/28/2020] [Indexed: 05/21/2023]
Abstract
Electrical signals (ESs) can be induced by local action of stressors in plants; they influence numerous physiological processes (photosynthesis, transpiration, respiration, genes expression, synthesis of phytohormones, etc.) and, thereby, induce a systemic adaptation response. Development of optical methods of a remote sensing of this response can be important for agricultural and ecological monitoring. Preliminarily, we showed (Sukhova et al., Plant Sign Behav 2019; 14:e1610301) that burning-induced ESs induced changes in leaf reflectance at broad spectral bands (400-500, 500-600, 600-700, and 700-800 nm). The aims of the present work were (i) investigation of ESs influence on difference reflectance indices (RIs) calculated on the basis of these broad spectral bands and (ii) analysis of connection of the indices with water content in plants. Pea seedlings were investigated. ESs were induced by burning of the first mature leaf; ESs had high amplitudes in the second leaf and had low amplitudes in the fourth leaf. It was shown that ESs induced significant changes in RIs, which were calculated on basis of intensities of the reflected light at (i) 400-500 and 600-700 nm, (ii) 500-600 and 700-800 nm, and (iii) 600-700 and 700-800 nm. The effect was strong in the second leaf and weak in the fourth leaf; that is, the response was dependent on the magnitude of ESs. ESs-induced changes in RI were strongly connected with ESs-induced decrease of leaf water content which was estimated on basis of decrease of water index. Thus, broadband RIs can be used for revealing the ESs-induced systemic stress response in plants.
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Affiliation(s)
- Ekaterina Sukhova
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Lyubov Yudina
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Ekaterina Gromova
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Vladimir Nerush
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Vladimir Vodeneev
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
| | - Vladimir Sukhov
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
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21
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Volkov AG, Toole S, WaMaina M. Electrical signal transmission in the plant-wide web. Bioelectrochemistry 2019; 129:70-78. [DOI: 10.1016/j.bioelechem.2019.05.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Revised: 05/05/2019] [Accepted: 05/05/2019] [Indexed: 12/26/2022]
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22
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Bulychev AA, Krupenina NA. Interchloroplast communications in Chara are suppressed under the alkaline bands and are relieved after the plasma membrane excitation. Bioelectrochemistry 2019; 129:62-69. [PMID: 31103848 DOI: 10.1016/j.bioelechem.2019.05.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 05/10/2019] [Accepted: 05/10/2019] [Indexed: 12/25/2022]
Abstract
Immobile chloroplasts in Chara internodal cells release photometabolites into the streaming cytoplasm that distributes the exported solutes and provides metabolic connectivity between spatially remote plastids. The metabolite transmission by fluid flow is evident from chlorophyll fluorescence changes in shaded chloroplasts upon local illumination applied upstream of the analyzed area. The connectivity correlates with the pH pattern on cell surface: it is strong in cell regions with high H+-pump activity and is low in regions featuring large passive H+ influx (OH- efflux). One explanation for low connectivity under the alkaline bands is that H+ influx lowers the cytoplasmic pH, thus retarding metabolic conversions of solutes carried by the microfluidic transporter. The cessation of H+ influx across the plasma membrane by eliciting the action potential and by adding NH4Cl into the medium greatly enhanced the amplitude of cyclosis-mediated fluorescence transients. The transition from latent to the transmissive state after the dark pretreatment was paralleled by the temporary increase in chlorophyll fluorescence, reflecting changes in photosynthetic electron transport. It is proposed that the connectivity between distant chloroplasts is controlled by cytoplasmic pH.
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Affiliation(s)
- Alexander A Bulychev
- Department of Biophysics, Faculty of Biology, Moscow State University, 119991 Moscow, Russia.
| | - Natalia A Krupenina
- Department of Biophysics, Faculty of Biology, Moscow State University, 119991 Moscow, Russia
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23
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Hedrich R. Diatom Signaling: A Novel Channel Type Identified. Curr Biol 2019; 29:R319-R321. [PMID: 31063722 DOI: 10.1016/j.cub.2019.03.038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Our nerve and muscle cells communicate using voltage-dependent four-domain sodium channels. A recent study in eukaryotic phytoplankton reveals that single-domain, prokaryote-like, voltage-gated Na+- and Ca2+-permeable channels are key to environmental sensing in the oceans.
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Affiliation(s)
- Rainer Hedrich
- University of Würtzburg, Biocentre, Julius-von-Sachs-Institut for Biosciences, Department of Molecular Plant Physiology and Biophysics, Würtzburg, Germany.
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24
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Chara braunii genome: a new resource for plant electrophysiology. Biophys Rev 2019; 11:235-239. [PMID: 30830677 DOI: 10.1007/s12551-019-00512-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 02/20/2019] [Indexed: 10/27/2022] Open
Abstract
The large-celled green alga Chara provided early electrophysiological data, but this model organism lost popularity once the smaller cells of higher plants became accessible to electrophysiology and genetic manipulation. However, with the sequencing of the Chara braunii genome (Nishiyama et al. Cell 174: 448-464, 2018), the molecular identity of the underlaying ion transporters in Characeae can be found and placed in evolutionary context. As Characeae are close to ancestors of land plants, the wealth of electrophysiological data will provide insights into important aspects of plant physiology, such as salt tolerance and sensitivity, carbon concentrating mechanisms, pH banding and the action potential generation.
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25
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Sukhov V, Sukhova E, Gromova E, Surova L, Nerush V, Vodeneev V. The electrical signal-induced systemic photosynthetic response is accompanied by changes in the photochemical reflectance index in pea. FUNCTIONAL PLANT BIOLOGY : FPB 2019; 46:328-338. [PMID: 32172742 DOI: 10.1071/fp18224] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Accepted: 11/23/2018] [Indexed: 06/10/2023]
Abstract
Plants can be affected by numerous environmental stressors with spatially heterogeneous actions on their bodies. A fast systemic photosynthetic response, which is connected with long-distance electrical signalling, plays an important role in the adaptation of higher plants to the action of stressors. Potentially, measurement of the response by using a photochemical reflectance index (PRI) could be the basis of monitoring photosynthesis under spatially heterogeneous stressors; however, the method has not been previously used for investigating the systemic photosynthetic response. We investigated changes in PRI and photosynthetic parameters (quantum yields of PSI and PSII and nonphotochemical quenching) in intact leaves of pea (Pisum sativum L.) after local heating of another leaf and the propagation of electrical signals through the plant body. We showed that electrical signals decreased the quantum yields of PSI and PSII and increased the nonphotochemical quenching of intact leaves in times ranging from minutes to tens of minutes; the changes were strongly connected with changes in PRI. Additional analysis showed that changes in PRI were caused by an increase of the energy-dependent quenching induced by electrical signals. Thus PRI can be potentially used for monitoring the systemic photosynthetic response connected with long-distance electrical signalling.
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Affiliation(s)
- Vladimir Sukhov
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
| | - Ekaterina Sukhova
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
| | - Ekaterina Gromova
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
| | - Lyubov Surova
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
| | - Vladimir Nerush
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
| | - Vladimir Vodeneev
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, 603950, Russia
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26
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Lapeikaite I, Dragunaite U, Pupkis V, Ruksenas O, Kisnieriene V. Asparagine alters action potential parameters in single plant cell. PROTOPLASMA 2019; 256:511-519. [PMID: 30291442 DOI: 10.1007/s00709-018-1315-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Accepted: 09/25/2018] [Indexed: 06/08/2023]
Abstract
Effect of amino acid L-asparagine on electrical signalling of single Nitellopsis obtusa (Characeaen) cell was investigated using glass-microelectrode technique in current-clamp and voltage-clamp modes. Cell exposure for 30 min to 0.1 mM and 1 mM of asparagine resulted in changes of electrically stimulated action potential (AP) parameters in comparison to standard conditions. Results indicate that asparagine acts in dose-dependent manner: increases AP amplitude by hyperpolarizing AP threshold potential (Eth), prolongs action potential repolarization, increases maximum Cl- efflux amplitude along with the increase of activation and inactivation durations. Presented findings provide new aspects of exogenous amino acids' effect on plants' electrical signalling with emphasis on separate single plant cell excitability and AP characteristics.
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Affiliation(s)
- Indre Lapeikaite
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Ave. 7, LT-10257, Vilnius, Lithuania.
| | - Ugne Dragunaite
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Ave. 7, LT-10257, Vilnius, Lithuania
| | - Vilmantas Pupkis
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Ave. 7, LT-10257, Vilnius, Lithuania
| | - Osvaldas Ruksenas
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Ave. 7, LT-10257, Vilnius, Lithuania
| | - Vilma Kisnieriene
- Institute of Biosciences, Life Sciences Centre, Vilnius University, Sauletekio Ave. 7, LT-10257, Vilnius, Lithuania
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27
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Mussel M, Schneider MF. Similarities between action potentials and acoustic pulses in a van der Waals fluid. Sci Rep 2019; 9:2467. [PMID: 30792493 PMCID: PMC6385226 DOI: 10.1038/s41598-019-38826-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Accepted: 01/08/2019] [Indexed: 11/10/2022] Open
Abstract
An action potential is typically described as a purely electrical change that propagates along the membrane of excitable cells. However, recent experiments have demonstrated that non-linear acoustic pulses that propagate along lipid interfaces and traverse the melting transition, share many similar properties with action potentials. Despite the striking experimental similarities, a comprehensive theoretical study of acoustic pulses in lipid systems is still lacking. Here we demonstrate that an idealized description of an interface near phase transition captures many properties of acoustic pulses in lipid monolayers, as well as action potentials in living cells. The possibility that action potentials may better be described as acoustic pulses in soft interfaces near phase transition is illustrated by the following similar properties: correspondence of time and velocity scales, qualitative pulse shape, sigmoidal response to stimulation amplitude (an 'all-or-none' behavior), appearance in multiple observables (particularly, an adiabatic change of temperature), excitation by many types of stimulations, as well as annihilation upon collision. An implication of this work is that crucial functional information of the cell may be overlooked by focusing only on electrical measurements.
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Affiliation(s)
- Matan Mussel
- Department of Physics, Technical University of Dortmund, 44227, Dortmund, Germany.
- Department of Physics, University of Augsburg, 86159, Augsburg, Germany.
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA.
| | - Matthias F Schneider
- Department of Physics, Technical University of Dortmund, 44227, Dortmund, Germany
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Fillafer C, Mussel M, Muchowski J, Schneider MF. Cell Surface Deformation during an Action Potential. Biophys J 2019; 114:410-418. [PMID: 29401438 DOI: 10.1016/j.bpj.2017.11.3776] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 10/24/2017] [Accepted: 11/27/2017] [Indexed: 11/29/2022] Open
Abstract
The excitation of many cells and tissues is associated with cell mechanical changes. The evidence presented herein corroborates that single cells deform during an action potential. It is demonstrated that excitation of plant cells (Chara braunii internodes) is accompanied by out-of-plane displacements of the cell surface in the micrometer range (∼1-10 μm). The onset of cellular deformation coincides with the depolarization phase of the action potential. The mechanical pulse: 1) propagates with the same velocity as the electrical pulse (within experimental accuracy, ∼10 mm s-1), 2) is reversible, 3) in most cases is of biphasic nature (109 out of 152 experiments), and 4) is presumably independent of actin-myosin-motility. The existence of transient mechanical changes in the cell cortex is confirmed by micropipette aspiration experiments. A theoretical analysis demonstrates that this observation can be explained by a reversible change in the mechanical properties of the cell surface (transmembrane pressure, surface tension, and bending rigidity). Taken together, these findings contribute to the ongoing debate about the physical nature of cellular excitability.
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Affiliation(s)
- Christian Fillafer
- Department of Physics, Technical University of Dortmund, Dortmund, Germany
| | - Matan Mussel
- Department of Physics, Technical University of Dortmund, Dortmund, Germany; Department of Physics, University of Augsburg, Augsburg, Germany
| | - Julia Muchowski
- Department of Physics, Technical University of Dortmund, Dortmund, Germany
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Baluška F, Mancuso S. Actin Cytoskeleton and Action Potentials: Forgotten Connections. THE CYTOSKELETON 2019. [DOI: 10.1007/978-3-030-33528-1_5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Volkov AG, Shtessel YB. Electrical signal propagation within and between tomato plants. Bioelectrochemistry 2018; 124:195-205. [DOI: 10.1016/j.bioelechem.2018.08.001] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2018] [Revised: 08/02/2018] [Accepted: 08/04/2018] [Indexed: 12/23/2022]
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Long-distance electrical signals as a link between the local action of stressors and the systemic physiological responses in higher plants. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 2018; 146:63-84. [PMID: 30508537 DOI: 10.1016/j.pbiomolbio.2018.11.009] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/23/2018] [Accepted: 11/24/2018] [Indexed: 12/27/2022]
Abstract
Our review is devoted to the analysis of the role of long-distance electrical signals in the development of the fast systemic physiological responses in higher plants. The characteristics and mechanisms of basic electrical signals (variation potential, action potential and system potential) are analyzed, and a potential schema of the generation and propagation of the system potential is proposed. The review summarizes the physiological changes induced by the variation potential, action potential and system potential in higher plants, including changes in gene expressions, the production of phytohormones, photosynthesis, phloem mass-flow, respiration, ATP content, transpiration and plant growth. Potential mechanisms of the changes are analyzed. Finally, a hypothetical schema, which describes a hierarchy of the variation potential, action potential and system potential, in the development of the fast systemic non-specific adaptation of plants to stressors, is proposed.
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Edel KH, Marchadier E, Brownlee C, Kudla J, Hetherington AM. The Evolution of Calcium-Based Signalling in Plants. Curr Biol 2018; 27:R667-R679. [PMID: 28697370 DOI: 10.1016/j.cub.2017.05.020] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The calcium-based intracellular signalling system is used ubiquitously to couple extracellular stimuli to their characteristic intracellular responses. It is becoming clear from genomic and physiological investigations that while the basic elements in the toolkit are common between plants and animals, evolution has acted in such a way that, in plants, some components have diversified with respect to their animal counterparts, while others have either been lost or have never evolved in the plant lineages. In comparison with animals, in plants there appears to have been a loss of diversity in calcium-influx mechanisms at the plasma membrane. However, the evolution of the calcium-storing vacuole may provide plants with additional possibilities for regulating calcium influx into the cytosol. Among the proteins that are involved in sensing and responding to increases in calcium, plants possess specific decoder proteins that are absent from the animal lineage. In seeking to understand the selection pressures that shaped the plant calcium-signalling toolkit, we consider the evolution of fast electrical signalling. We also note that, in contrast to animals, plants apparently do not make extensive use of cyclic-nucleotide-based signalling. It is possible that reliance on a single intracellular second-messenger-based system, coupled with the requirement to adapt to changing environmental conditions, has helped to define the diversity of components found in the extant plant calcium-signalling toolkit.
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Affiliation(s)
- Kai H Edel
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 7, 48149 Münster, Germany
| | - Elodie Marchadier
- School of Biological Sciences, Life Sciences Building, University of Bristol, Tyndall Avenue, Bristol BS8 1TQ, UK; Génétique Quantitative et Evolution - Le Moulon, INRA, Univ. Paris-Sud, CNRS, AgroParisTech, Université Paris-Saclay, 91190 Gif-sur-Yvette, France
| | - Colin Brownlee
- Marine Biological Association of the UK, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK; School of Ocean and Earth Sciences, University of Southampton, Southampton, SO14 3ZH, UK
| | - Jörg Kudla
- Institut für Biologie und Biotechnologie der Pflanzen, Universität Münster, Schlossplatz 7, 48149 Münster, Germany
| | - Alistair M Hetherington
- School of Biological Sciences, Life Sciences Building, University of Bristol, Tyndall Avenue, Bristol BS8 1TQ, UK.
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Nishiyama T, Sakayama H, de Vries J, Buschmann H, Saint-Marcoux D, Ullrich KK, Haas FB, Vanderstraeten L, Becker D, Lang D, Vosolsobě S, Rombauts S, Wilhelmsson PK, Janitza P, Kern R, Heyl A, Rümpler F, Villalobos LIAC, Clay JM, Skokan R, Toyoda A, Suzuki Y, Kagoshima H, Schijlen E, Tajeshwar N, Catarino B, Hetherington AJ, Saltykova A, Bonnot C, Breuninger H, Symeonidi A, Radhakrishnan GV, Van Nieuwerburgh F, Deforce D, Chang C, Karol KG, Hedrich R, Ulvskov P, Glöckner G, Delwiche CF, Petrášek J, Van de Peer Y, Friml J, Beilby M, Dolan L, Kohara Y, Sugano S, Fujiyama A, Delaux PM, Quint M, Theißen G, Hagemann M, Harholt J, Dunand C, Zachgo S, Langdale J, Maumus F, Van Der Straeten D, Gould SB, Rensing SA. The Chara Genome: Secondary Complexity and Implications for Plant Terrestrialization. Cell 2018; 174:448-464.e24. [DOI: 10.1016/j.cell.2018.06.033] [Citation(s) in RCA: 271] [Impact Index Per Article: 45.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 03/27/2018] [Accepted: 06/14/2018] [Indexed: 01/11/2023]
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Sukhova E, Mudrilov M, Vodeneev V, Sukhov V. Influence of the variation potential on photosynthetic flows of light energy and electrons in pea. PHOTOSYNTHESIS RESEARCH 2018; 136:215-228. [PMID: 29086893 DOI: 10.1007/s11120-017-0460-1] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2017] [Accepted: 10/23/2017] [Indexed: 05/17/2023]
Abstract
Local damage (mainly burning, heating, and mechanical wounding) induces propagation of electrical signals, namely, variation potentials, which are important signals during the life of plants that regulate different physiological processes, including photosynthesis. It is known that the variation potential decreases the rate of CO2 assimilation by the Calvin-Benson cycle; however, its influence on light reactions has been poorly investigated. The aim of our work was to investigate the influence of the variation potential on the light energy flow that is absorbed, trapped and dissipated per active reaction centre in photosystem II and on the flow of electrons through the chloroplast electron transport chain. We analysed chlorophyll fluorescence in pea leaves using JIP-test and PAM-fluorometry; we also investigated delayed fluorescence. The electrical signals were registered using extracellular electrodes. We showed that the burning-induced variation potential stimulated a nonphotochemical loss of energy in photosystem II under dark conditions. It was also shown that the variation potential gradually increased the flow of light energy absorbed, trapped and dissipated by photosystem II. These changes were likely caused by an increase in the fraction of absorbed light distributed to photosystem II. In addition, the variation potential induced a transient increase in electron flow through the photosynthetic electron transport chain. Some probable mechanisms for the influence of the variation potential on the light reactions of photosynthesis (including the potential role of intracellular pH decrease) are discussed in the work.
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Affiliation(s)
- Ekaterina Sukhova
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue, 23, Nizhny Novgorod, Russia, 603950
| | - Maxim Mudrilov
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue, 23, Nizhny Novgorod, Russia, 603950
| | - Vladimir Vodeneev
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue, 23, Nizhny Novgorod, Russia, 603950
| | - Vladimir Sukhov
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue, 23, Nizhny Novgorod, Russia, 603950.
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Cuin TA, Dreyer I, Michard E. The Role of Potassium Channels in Arabidopsis thaliana Long Distance Electrical Signalling: AKT2 Modulates Tissue Excitability While GORK Shapes Action Potentials. Int J Mol Sci 2018; 19:E926. [PMID: 29561764 PMCID: PMC5979599 DOI: 10.3390/ijms19040926] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Revised: 03/12/2018] [Accepted: 03/18/2018] [Indexed: 01/14/2023] Open
Abstract
Fast responses to an external threat depend on the rapid transmission of signals through a plant. Action potentials (APs) are proposed as such signals. Plant APs share similarities with their animal counterparts; they are proposed to depend on the activity of voltage-gated ion channels. Nonetheless, despite their demonstrated role in (a)biotic stress responses, the identities of the associated voltage-gated channels and transporters remain undefined in higher plants. By demonstrating the role of two potassium-selective channels in Arabidopsis thaliana in AP generation and shaping, we show that the plant AP does depend on similar Kv-like transport systems to those of the animal signal. We demonstrate that the outward-rectifying potassium-selective channel GORK limits the AP amplitude and duration, while the weakly-rectifying channel AKT2 affects membrane excitability. By computational modelling of plant APs, we reveal that the GORK activity not only determines the length of an AP but also the steepness of its rise and the maximal amplitude. Thus, outward-rectifying potassium channels contribute to both the repolarisation phase and the initial depolarisation phase of the signal. Additionally, from modelling considerations we provide indications that plant APs might be accompanied by potassium waves, which prime the excitability of the green cable.
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Affiliation(s)
- Tracey Ann Cuin
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.
- SupAgro Montpellier, 2, Place Viala, 34060 Montpellier, France.
| | - Ingo Dreyer
- Centro de Bioinformática y Simulación Molecular (CBSM), Universidad de Talca, 2 Norte 685, 3460000 Talca, Chile.
| | - Erwan Michard
- SupAgro Montpellier, 2, Place Viala, 34060 Montpellier, France.
- Cell Biology and Molecular Genetics, Biosciences Research Building, University of Maryland, College Park, MD 20742, USA.
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Mussel M, Fillafer C, Ben-Porath G, Schneider MF. Surface deformation during an action potential in pearled cells. Phys Rev E 2018; 96:052406. [PMID: 29347751 DOI: 10.1103/physreve.96.052406] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Indexed: 01/03/2023]
Abstract
Electric pulses in biological cells (action potentials) have been reported to be accompanied by a propagating cell-surface deformation with a nanoscale amplitude. Typically, this cell surface is covered by external layers of polymer material (extracellular matrix, cell wall material, etc.). It was recently demonstrated in excitable plant cells (Chara braunii) that the rigid external layer (cell wall) hinders the underlying deformation. When the cell membrane was separated from the cell wall by osmosis, a mechanical deformation, in the micrometer range, was observed upon excitation of the cell. The underlying mechanism of this mechanical pulse has, to date, remained elusive. Herein we report that Chara cells can undergo a pearling instability, and when the pearled fragments were excited even larger and more regular cell shape changes were observed (∼10-100μm in amplitude). These transient cellular deformations were captured by a curvature model that is based on three parameters: surface tension, bending rigidity, and pressure difference across the surface. In this paper these parameters are extracted by curve-fitting to the experimental cellular shapes at rest and during excitation. This is a necessary step to identify the mechanical parameters that change during an action potential.
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Affiliation(s)
- Matan Mussel
- Department of Physics, Technical University of Dortmund, 44227 Dortmund, Germany.,Department of Physics, University of Augsburg, 86159 Augsburg, Germany
| | - Christian Fillafer
- Department of Physics, Technical University of Dortmund, 44227 Dortmund, Germany
| | - Gal Ben-Porath
- Center for Mathematical Philosophy, Ludwig Maximilian University, 80539 Munich, Germany
| | - Matthias F Schneider
- Department of Physics, Technical University of Dortmund, 44227 Dortmund, Germany
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Kisnieriene V, Lapeikaite I, Pupkis V. Electrical signalling in Nitellopsis obtusa: potential biomarkers of biologically active compounds. FUNCTIONAL PLANT BIOLOGY : FPB 2018; 45:132-142. [PMID: 32291027 DOI: 10.1071/fp16339] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2016] [Accepted: 02/19/2017] [Indexed: 06/11/2023]
Abstract
The Nitellopsis obtusa (N.A.Desvaux) J.Groves cell provides a model system for complex investigation of instantaneous effects of various biologically active compounds (BC) on the generation of plant bioelectrical signals in vivo. Experimental evidence using multiple electrical signals as biomarkers of the effects of BC (acetylcholine, asparagine, glutamate, nicotine, aluminium, nickel and cadmium ions) is provided. The effect of BC on membrane transport systems involved in the cell excitability were tested by current clamp, voltage clamp and patch clamp methods. Membrane potential (MP) alterations and action potential (AP) patterns in response to BC were shown to represent the cell state. High discretisation frequency allows precise, high time resolution analysis of real-time processes measuring changes in excitation threshold, AP amplitude and velocity of repolarisation values after application of BC indicating the effect on ion channels involved in AP generation. Application of voltage clamp revealed that changes in AP peak value were caused not only by increment in averaged maximum amplitude of the Cl- current, but in prolonged Cl- channels' opening time also. The cytoplasmic droplet can serve as a model system in which the effects of BC on single tonoplast ion channel can be studied by patch clamping. Investigation of electrical cell-to-cell communication revealed evidence on the electrical signal transduction through plasmodesmata.
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Affiliation(s)
- Vilma Kisnieriene
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, Vilnius, Sauletekio av. 7, LT-10257, Lithuania
| | - Indre Lapeikaite
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, Vilnius, Sauletekio av. 7, LT-10257, Lithuania
| | - Vilmantas Pupkis
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, Vilnius, Sauletekio av. 7, LT-10257, Lithuania
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Sukhov V, Gaspirovich V, Mysyagin S, Vodeneev V. High-Temperature Tolerance of Photosynthesis Can Be Linked to Local Electrical Responses in Leaves of Pea. Front Physiol 2017; 8:763. [PMID: 29033854 PMCID: PMC5627542 DOI: 10.3389/fphys.2017.00763] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 09/19/2017] [Indexed: 11/16/2022] Open
Abstract
It is known that numerous stimuli induce electrical signals which can increase a plant's tolerance to stressors, including high temperature. However, the physiological role of local electrical responses (LERs), i.e., responses in the zone of stimulus action, in the plant's tolerance has not been sufficiently investigated. The aim of a current work is to analyze the connection between parameters of LERs with the thermal tolerance of photosynthetic processes in pea. Electrical activity and photosynthetic parameters in pea leaves were registered during transitions of air temperature in a measurement head (from 23 to 30°C, from 30 to 40°C, from 40 to 45°C, and from 45 to 23°C). This stepped heating decreased a photosynthetic assimilation of CO2 and induced generation of LERs in the heated leaf. Amplitudes of LERs, quantity of responses during the heating and the number of temperature transition, which induced the first generation of LERs, varied among different pea plants. Parameters of LERs were weakly connected with the photosynthetic assimilation of CO2 during the heating; however, a residual photosynthetic activity after a treatment by high temperatures increased with the growth of amplitudes and quantity of LERs and with lowering of the number of the heating transition, inducing the first electrical response. The effect was not connected with a photosynthetic activity before heating; similar dependences were also observed for effective and maximal quantum yields of photosystem II after heating. We believe that the observed effect can reflect a positive influence of LERs on the thermal tolerance of photosynthesis. It is possible that the process can participate in a plant's adaptation to stressors.
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Affiliation(s)
- Vladimir Sukhov
- Department of Biophysics, N.I. Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Russia
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Fillafer C, Paeger A, Schneider MF. Collision of two action potentials in a single excitable cell. Biochim Biophys Acta Gen Subj 2017; 1861:3282-3286. [PMID: 28965878 DOI: 10.1016/j.bbagen.2017.09.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Revised: 09/08/2017] [Accepted: 09/27/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND It is a common incident in nature, that two waves or pulses run into each other head-on. The outcome of such an event is of special interest, because it allows conclusions about the underlying physical nature of the pulses. The present experimental study dealt with the head-on meeting of two action potentials (AP) in a single excitable plant cell (Chara braunii internode). METHODS The membrane potential was monitored with multiple sensors along a single excitable cell. In control experiments, an AP was excited electrically at either end of the cell cylinder. Subsequently, stimuli were applied simultaneously at both ends of the cell in order to generate two APs that met each other head-on. RESULTS When two action potentials propagated into each other, the pulses did not penetrate but annihilated (N=26 experiments in n=10 cells). CONCLUSIONS APs in excitable plant cells did not penetrate upon meeting head-on. In the classical electrical model, this behavior is specifically attributed to relaxation of ion channel proteins. From an acoustic point of view, annihilation can be viewed as a result of nonlinear material properties (e.g. a phase change). GENERAL SIGNIFICANCE The present results suggest that APs in excitable animal and plant cells belong to a similar class of nonlinear phenomena. Intriguingly, other excitation waves in biology (intracellular waves, cortical spreading depression, etc.) also annihilate upon collision and are thus expected to follow the same underlying principles as the observed action potentials.
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Affiliation(s)
- Christian Fillafer
- Medical and Biological Physics, Faculty of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Anne Paeger
- Medical and Biological Physics, Faculty of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227 Dortmund, Germany
| | - Matthias F Schneider
- Medical and Biological Physics, Faculty of Physics, Technical University Dortmund, Otto-Hahn-Str. 4, 44227 Dortmund, Germany.
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Bhatia S, Singh P, Sharma P. Hodgkin-Huxley model based on ionic transport in axoplasmic fluid. J Integr Neurosci 2017; 16:401-417. [PMID: 28891525 DOI: 10.3233/jin-170029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Hodgkin-Huxley model has been reframed to incorporate the physical parameters of fluid inside the axon. The reframed model comprises of set of partial differential equations containing the physical parameters: density, mass fraction of sodium, potassium and chlorine ions, longitudinal diffusivity of ions and rate of additions of ions along with the temperature. Obtained conduction velocity of 19.5m/sec at a temperature of 18.5 degree celcius and conduction velocity dependency on temperature within the range 5 to 25 degree celcius are two important results that strongly validate the proposed model. The behavior of all the physical parameters has been characterized with respect to the action potential. Action potential conduction velocity along with axoplasmic fluid viscosity has been characterized with respect to different temperatures. Longitudinal diffusivity of ions is also quantified.
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Affiliation(s)
- Suman Bhatia
- Department of CSE&IT, The NorthCap University, Sec-23A Gurugram, 122017, India. E-mail:
| | - Phool Singh
- Department of Applied Sciences, The NorthCap University, Sec-23A Gurugram, 122017, India. E-mails: ,
| | - Prabha Sharma
- Department of Applied Sciences, The NorthCap University, Sec-23A Gurugram, 122017, India. E-mails: ,
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Mathematical Models of Electrical Activity in Plants. J Membr Biol 2017; 250:407-423. [PMID: 28711950 DOI: 10.1007/s00232-017-9969-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Accepted: 07/11/2017] [Indexed: 10/19/2022]
Abstract
Electrical activity plays an important role in plant life; in particular, electrical responses can participate in the reception of the action of stressors (local electrical responses and oscillations) and signal transduction into unstimulated parts of the plant (action potential, variation potential and system potential). Understanding the mechanisms of electrical responses and subsequent changes in physiological processes and the prediction of plant responses to stressors requires the elaboration of mathematical models of electrical activity in plant organisms. Our review describes approaches to the simulation of plant electrogenesis and summarizes current models of electrical activity in these organisms. It is shown that there are numerous models of the generation of electrical responses, which are based on various descriptions (from modifications of the classical Hodgkin-Huxley model to detailed models, which consider ion transporters, regulatory processes, buffers, etc.). A moderate number of works simulate the propagation of electrical signals using equivalent electrical circuits, systems of excitable elements with local electrical coupling and descriptions of chemical signal propagation. The transmission of signals from a plasma membrane to intracellular compartments (endoplasmic reticulum, vacuole) during the generation of electrical responses is much less modelled. Finally, only a few works simulate plant physiological changes that are connected with electrical responses or investigate the inverse problem: reconstruction of the type and parameters of stimuli through the analysis of electrical responses. In the conclusion of the review, we discuss future perspectives on the simulation of electrical activity in plants.
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Novikova EM, Vodeneev VA, Sukhov VS. Mathematical model of action potential in higher plants with account for the involvement of vacuole in the electrical signal generation. BIOCHEMISTRY MOSCOW SUPPLEMENT SERIES A-MEMBRANE AND CELL BIOLOGY 2017. [DOI: 10.1134/s1990747817010068] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Sukhov V. Electrical signals as mechanism of photosynthesis regulation in plants. PHOTOSYNTHESIS RESEARCH 2016; 130:373-387. [PMID: 27154573 DOI: 10.1007/s11120-016-0270-x] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 04/26/2016] [Indexed: 05/24/2023]
Abstract
This review summarizes current works concerning the effects of electrical signals (ESs) on photosynthesis, the mechanisms of the effects, and its physiological role in plants. Local irritations of plants induce various photosynthetic responses in intact leaves, including fast and long-term inactivation of photosynthesis, and its activation. Irritation-induced ESs, including action potential, variation potential, and system potential, probably causes the photosynthetic responses in intact leaves. Probable mechanisms of induction of fast inactivation of photosynthesis are associated with Ca2+- and (or) H+-influxes during ESs generation; long-term inactivation of photosynthesis might be caused by Ca2+- and (or) H+-influxes, production of abscisic and jasmonic acids, and inactivation of phloem H+-sucrose symporters. It is probable that subsequent development of inactivation of photosynthesis is mainly associated with decreased CO2 influx and inactivation of the photosynthetic dark reactions, which induces decreased photochemical quantum yields of photosystems I and II and increased non-photochemical quenching of photosystem II fluorescence and cyclic electron flow around photosystem I. However, other pathways of the ESs influence on the photosynthetic light reactions are also possible. One of them might be associated with ES-connected acidification of chloroplast stroma inducing ferredoxin-NADP+ reductase accumulation at the thylakoids in Tic62 and TROL complexes. Mechanisms of ES-induced activation of photosynthesis require further investigation. The probable ultimate effect of ES-induced photosynthetic responses in plant life is the increased photosynthetic machinery resistance to stressors, including high and low temperatures, and enhanced whole-plant resistance to environmental factors at least during 1 h after irritation.
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Affiliation(s)
- Vladimir Sukhov
- Department of Biophysics, N. I. Lobachevsky State University of Nizhny Novgorod, Gagarin Avenue 23, Nizhny Novgorod, Russia, 603950.
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Baluška F, Yokawa K, Mancuso S, Baverstock K. Understanding of anesthesia - Why consciousness is essential for life and not based on genes. Commun Integr Biol 2016; 9:e1238118. [PMID: 28042377 PMCID: PMC5193047 DOI: 10.1080/19420889.2016.1238118] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Revised: 08/05/2016] [Accepted: 09/14/2016] [Indexed: 01/14/2023] Open
Abstract
Anesthesia and consciousness represent 2 mysteries not only for biology but also for physics and philosophy. Although anesthesia was introduced to medicine more than 160 y ago, our understanding of how it works still remains a mystery. The most prevalent view is that the human brain and its neurons are necessary to impose the effects of anesthetics. However, the fact is that all life can be anesthesized. Numerous theories have been generated trying to explain the major impact of anesthetics on our human-specific consciousness; switching it off so rapidly, but no single theory resolves this enduring mystery. The speed of anesthetic actions precludes any direct involvement of genes. Lipid bilayers, cellular membranes, and critical proteins emerge as the most probable primary targets of anesthetics. Recent findings suggest, rather surprisingly, that physical forces underlie both the anesthetic actions on living organisms as well as on consciousness in general.
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Affiliation(s)
| | - Ken Yokawa
- IZMB, University of Bonn, Kirschalle, Bonn, Germany
| | - Stefano Mancuso
- Department of Plant, Soil and Environmental Science & LINV, University of Florence, Sesto Fiorentino, Italy
| | - Keith Baverstock
- Department of Environmental Science, University of Eastern Finland, Kuopio, Finland
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Vodeneev VA, Katicheva LA, Sukhov VS. Electrical signals in higher plants: Mechanisms of generation and propagation. Biophysics (Nagoya-shi) 2016. [DOI: 10.1134/s0006350916030209] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Sukhov V, Surova L, Morozova E, Sherstneva O, Vodeneev V. Changes in H(+)-ATP Synthase Activity, Proton Electrochemical Gradient, and pH in Pea Chloroplast Can Be Connected with Variation Potential. FRONTIERS IN PLANT SCIENCE 2016; 7:1092. [PMID: 27499760 PMCID: PMC4956672 DOI: 10.3389/fpls.2016.01092] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Accepted: 07/11/2016] [Indexed: 05/22/2023]
Abstract
Local stimulation induces generation and propagation of electrical signals, including the variation potential (VP) and action potential, in plants. Burning-induced VP changes the physiological state of plants; specifically, it inactivates photosynthesis. However, the mechanisms that decrease photosynthesis are poorly understood. We investigated these mechanisms by measuring VP-connected systemic changes in CO2 assimilation, parameters of light reactions of photosynthesis, electrochromic pigment absorbance shifts, and light scattering. We reveal that inactivation of photosynthesis in the pea, including inactivation of dark and light reactions, was connected with the VP. Inactivation of dark reactions decreased the rate constant of the fast relaxation of the electrochromic pigment absorbance shift, which reflected a decrease in the H(+)-ATP synthase activity. This decrease likely contributed to the acidification of the chloroplast lumen, which developed after VP induction. However, VP-connected decrease of the proton motive force across the thylakoid membrane, possibly, reflected a decreased pH in the stroma. This decrease may be another mechanism of chloroplast lumen acidification. Overall, stroma acidification can decrease electron flow through photosystem I, and lumen acidification induces growth of fluorescence non-photochemical quenching and decreases electron flow through photosystem II, i.e., pH decreases in the stroma and lumen, possibly, contribute to the VP-induced inactivation of light reactions of photosynthesis.
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Affiliation(s)
- Vladimir Sukhov
- Department of Biophysics, N. I. Lobachevsky State University of Nizhny NovgorodNizhny Novgorod, Russia
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Kisnieriene V, Lapeikaite I, Sevriukova O, Ruksenas O. The effects of Ni(2+) on electrical signaling of Nitellopsis obtusa cells. JOURNAL OF PLANT RESEARCH 2016; 129:551-558. [PMID: 26875181 DOI: 10.1007/s10265-016-0794-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Accepted: 12/02/2015] [Indexed: 06/05/2023]
Abstract
The effect of nickel (Ni) on the generation of plant bioelectrical signals was evaluated in Nitellopsis obtusa, a Characean model organism. Conventional glass-microelectrode technique and K(+)-anaesthesia method in current-clamp and voltage-clamp modes were used for the measurement and analysis of electrical parameters. Ni(2+) treatment rapidly influenced the action potential (AP) parameters namely, excitation threshold, AP peak and duration, membrane potential at various voltages and dynamics of ion currents. We conclude that altered electrical signaling pathway in the test organism constituted the early target for Ni toxicity imposition. The observed Ni interference could be ascribed to disturbed [Ca(2+)]cyt content, impaired Cl(-) and K(+) channels activity resulting in decreased excitability and repolarization rate in generated AP.
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Affiliation(s)
- Vilma Kisnieriene
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania.
| | - Indre Lapeikaite
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania
| | - Olga Sevriukova
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania
| | - Osvaldas Ruksenas
- Department of Neurobiology and Biophysics, Faculty of Natural Science, Vilnius University, M. K. Ciurlionio 21/27, 03101, Vilnius, Lithuania
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Masi E, Ciszak M, Colzi I, Adamec L, Mancuso S. Resting electrical network activity in traps of the aquatic carnivorous plants of the genera Aldrovanda and Utricularia. Sci Rep 2016; 6:24989. [PMID: 27117956 PMCID: PMC4846995 DOI: 10.1038/srep24989] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 04/04/2016] [Indexed: 11/17/2022] Open
Abstract
In this study the MEA (multielectrode array) system was used to record electrical responses of intact and halved traps, and other trap-free tissues of two aquatic carnivorous plants, Aldrovanda vesiculosa and Utricularia reflexa. They exhibit rapid trap movements and their traps contain numerous glands. Spontaneous generation of spikes with quite uniform shape, propagating across the recording area, has been observed for all types of sample. In the analysis of the electrical network, higher richer synchronous activity was observed relative to other plant species and organs previously described in the literature: indeed, the time intervals between the synchronized clusters (the inter-spike intervals) create organized patterns and the propagation times vary non-linearly with the distance due to this synchronization. Interestingly, more complex electrical activity was found in traps than in trap-free organs, supporting the hypothesis that the nature of the electrical activity may reflect the anatomical and functional complexity of different organs. Finally, the electrical activity of functionally different traps of Aldrovanda (snapping traps) and Utricularia (suction traps) was compared and some differences in the features of signal propagation were found. According to these results, a possible use of the MEA system for the study of different trap closure mechanisms is proposed.
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Affiliation(s)
- Elisa Masi
- LINV, Department of Agrifood Production and Environmental Sciences (DISPAA), University of Florence, viale delle Idee 30, 50019 Sesto Fiorentino (FI), Italy
| | - Marzena Ciszak
- LINV, Department of Agrifood Production and Environmental Sciences (DISPAA), University of Florence, viale delle Idee 30, 50019 Sesto Fiorentino (FI), Italy
- CNR, National Institute of Optics (INO), L.go E. Fermi 6, 50125 Florence, Italy
| | - Ilaria Colzi
- LINV, Department of Agrifood Production and Environmental Sciences (DISPAA), University of Florence, viale delle Idee 30, 50019 Sesto Fiorentino (FI), Italy
| | - Lubomir Adamec
- Institute of Botany of the Czech Academy of Sciences, Section of Plant Ecology, Dukelská 135, CZ-379 82 Třeboň, Czech Republic
| | - Stefano Mancuso
- LINV, Department of Agrifood Production and Environmental Sciences (DISPAA), University of Florence, viale delle Idee 30, 50019 Sesto Fiorentino (FI), Italy
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Böhm J, Scherzer S, Shabala S, Krol E, Neher E, Mueller TD, Hedrich R. Venus Flytrap HKT1-Type Channel Provides for Prey Sodium Uptake into Carnivorous Plant Without Conflicting with Electrical Excitability. MOLECULAR PLANT 2016; 9:428-436. [PMID: 26455461 PMCID: PMC4791408 DOI: 10.1016/j.molp.2015.09.017] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Revised: 09/24/2015] [Accepted: 09/24/2015] [Indexed: 05/05/2023]
Abstract
The animal diet of the carnivorous Venus flytrap, Dionaea muscipula, contains a sodium load that enters the capture organ via an HKT1-type sodium channel, expressed in special epithelia cells on the inner trap lobe surface. DmHKT1 expression and sodium uptake activity is induced upon prey contact. Here, we analyzed the HKT1 properties required for prey sodium osmolyte management of carnivorous Dionaea. Analyses were based on homology modeling, generation of model-derived point mutants, and their functional testing in Xenopus oocytes. We showed that the wild-type HKT1 and its Na(+)- and K(+)-permeable mutants function as ion channels rather than K(+) transporters driven by proton or sodium gradients. These structural and biophysical features of a high-capacity, Na(+)-selective ion channel enable Dionaea glands to manage prey-derived sodium loads without confounding the action potential-based information management of the flytrap.
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Affiliation(s)
- J Böhm
- Julius-von-Sachs Institute, Department for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany
| | - S Scherzer
- Julius-von-Sachs Institute, Department for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany
| | - S Shabala
- School of Land and Food, University of Tasmania, Hobart TAS 7001, Australia
| | - E Krol
- Julius-von-Sachs Institute, Department for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany
| | - E Neher
- Zoology Department, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia; Department for Membrane Biophysics, Max Planck Institute for Biophysical Chemistry, 37077 Goettingen, Germany
| | - T D Mueller
- Julius-von-Sachs Institute, Department for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany.
| | - R Hedrich
- Julius-von-Sachs Institute, Department for Molecular Plant Physiology and Biophysics, University of Würzburg, Julius-von-Sachs Platz 2, 97082 Würzburg, Germany.
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Sukhov V, Surova L, Sherstneva O, Bushueva A, Vodeneev V. Variation potential induces decreased PSI damage and increased PSII damage under high external temperatures in pea. FUNCTIONAL PLANT BIOLOGY : FPB 2015; 42:727-736. [PMID: 32480716 DOI: 10.1071/fp15052] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 04/16/2015] [Indexed: 05/28/2023]
Abstract
Local burning of a leaf induces a unique electrical signal in plants: variation potential (VP), which can cause numerous functional responses, including changes in photosynthesis. The influences of VP on damage to photosynthetic machinery and thermal resistance of whole plant with heating were investigated in pea (Pisum sativum L.). Under high external temperature (53°C), VP induction was found to cause accelerated initial lowering of photosynthetic parameters, reduced transpiration rate, decreased PSI damage, and increased PSII damage. Increased PSI resistance was in good accordance with our previous data, but VP-induced stimulation of PSII damage under heating required further analysis. The magnitudes of leaf heating in experiments and controls were found to be different (~46-48°C after VP and ~44-45°C without it) under identical external temperatures and were connected with different transpiration rates under these conditions. Also PSII damage and the magnitude of leaf heating were strongly correlated. As a result, it was supposed that leaf temperature contributed to VP-induced stimulation of PSII damage with heating. Investigation of VP's influence on pea growth after heating showed that the electrical signal decreased plant growth suppression after heating (i.e. VP-induced increases in PSII damage did not noticeably influence thermal resistance in the whole plant).
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Affiliation(s)
- Vladimir Sukhov
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Gagarin Avenue, 23, 603950, Russia
| | - Lyubov Surova
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Gagarin Avenue, 23, 603950, Russia
| | - Oksana Sherstneva
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Gagarin Avenue, 23, 603950, Russia
| | - Albina Bushueva
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Gagarin Avenue, 23, 603950, Russia
| | - Vladimir Vodeneev
- Department of Biophysics, Lobachevsky State University of Nizhny Novgorod, Nizhny Novgorod, Gagarin Avenue, 23, 603950, Russia
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