Electrical Signals, Plant Tolerance to Actions of Stressors, and Programmed Cell Death: Is Interaction Possible?

In environmental conditions, plants are affected by abiotic and biotic stressors which can be heterogenous. This means that the systemic plant adaptive responses on their actions require long-distance stress signals including electrical signals (ESs). ESs are based on transient changes in the activities of ion channels and H+-ATP-ase in the plasma membrane. They influence numerous physiological processes, including gene expression, phytohormone synthesis, photosynthesis, respiration, phloem mass flow, ATP content, and many others. It is considered that these changes increase plant tolerance to the action of stressors; the effect can be related to stimulation of damages of specific molecular structures. In this review, we hypothesize that programmed cell death (PCD) in plant cells can be interconnected with ESs. There are the following points supporting this hypothesis. (i) Propagation of ESs can be related to ROS waves; these waves are a probable mechanism of PCD initiation. (ii) ESs induce the inactivation of photosynthetic dark reactions and activation of respiration. Both responses can also produce ROS and, probably, induce PCD. (iii) ESs stimulate the synthesis of stress phytohormones (e.g., jasmonic acid, salicylic acid, and ethylene) which are known to contribute to the induction of PCD. (iv) Generation of ESs accompanies K+ efflux from the cytoplasm that is also a mechanism of induction of PCD. Our review argues for the possibility of PCD induction by electrical signals and shows some directions of future investigations in the field.

Download Full-text

Programmed cell death with a necrotic-like phenotype

BioMolecular Concepts ◽

10.1515/bmc-2012-0056 ◽

2013 ◽

Vol 4 (3) ◽

pp. 259-275 ◽

Cited By ~ 9

Author(s):

Michael J. Morgan ◽

Zheng-gang Liu

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Mammalian Development ◽

Programmed Necrosis ◽

Physiological Processes ◽

Molecular Events ◽

Regulated Necrosis

AbstractProgrammed cell death is the process by which an individual cell in a multicellular organism commits cellular ‘suicide’ to provide a long-term benefit to the organism. Thus, programmed cell death is important for physiological processes such as development, cellular homeostasis, and immunity. Importantly, in this process, the cell is not eliminated in response to random events but in response to an intricate and genetically defined set of internal cellular molecular events or ‘program’. Although the apoptotic process is generally very well understood, programmed cell death that occurs with a necrotic-like phenotype has been much less studied, and it is only within the past few years that the necrotic program has begun to be elucidated. Originally, programmed necrosis was somewhat dismissed as a nonphysiological phenomenon that occurs in vitro. Recent in vivo studies, however, suggest that regulated necrosis is an authentic classification of cell death that is important in mammalian development and other physiological processes, and programmed necrosis is now considered a significant therapeutic target in major pathological processes as well. Although the RIP1-RIP3-dependent necrosome complex is recognized as being essential for the execution of many instances of programmed necrosis, other downstream and related necrotic molecules and pathways are now being characterized. One of the current challenges is understanding how and under what conditions these pathways are linked together.

Download Full-text

Electrical Signaling of Plants under Abiotic Stressors: Transmission of Stimulus-Specific Information

International Journal of Molecular Sciences ◽

10.3390/ijms221910715 ◽

2021 ◽

Vol 22 (19) ◽

pp. 10715

Author(s):

Maxim Mudrilov ◽

Maria Ladeynova ◽

Marina Grinberg ◽

Irina Balalaeva ◽

Vladimir Vodeneev

Keyword(s):

Abiotic Factors ◽

Electrical Signal ◽

Specific Information ◽

Systemic Response ◽

Long Distance ◽

Variation Potential ◽

Electrical Signals ◽

Physiological Processes ◽

Abiotic Stressors ◽

Electrical Signaling

Plants have developed complex systems of perception and signaling to adapt to changing environmental conditions. Electrical signaling is one of the most promising candidates for the regulatory mechanisms of the systemic functional response under the local action of various stimuli. Long-distance electrical signals of plants, such as action potential (AP), variation potential (VP), and systemic potential (SP), show specificities to types of inducing stimuli. The systemic response induced by a long-distance electrical signal, representing a change in the activity of a complex of molecular-physiological processes, includes a nonspecific component and a stimulus-specific component. This review discusses possible mechanisms for transmitting information about the nature of the stimulus and the formation of a specific systemic response with the participation of electrical signals induced by various abiotic factors.

Download Full-text

The Proapoptotic Gene Bad Regulates Brain Development via P53-Mediated Stress Signals in Zebrafish

Cells ◽

10.3390/cells10112820 ◽

2021 ◽

Vol 10 (11) ◽

pp. 2820

Author(s):

Jo-Chi Hung ◽

Jen-Leih Wu ◽

Huei-Ching Li ◽

Hsuan-Wen Chiu ◽

Jiann-Ruey Hong

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Brain Development ◽

Movement Behavior ◽

Caspase 8 ◽

Molecular Signaling ◽

Genome Wide ◽

Stress Signal ◽

Stress Signals ◽

Morpholino Oligonucleotides

Studies have shown that the BH3-only domain Bad regulates brain development via the control of programmed cell death (PCD), but very few studies have addressed its effect on the molecular signaling of brain development in the system. In this work, we examined the novel role of zebrafish Bad in initial programmed cell death for brain morphogenesis through the priming of p53-mediated stress signaling. In a biological function study on the knockdown of Bad by morpholino oligonucleotides, at 24 h post-fertilization (hpf) Bad defects induced abnormal hindbrain development, as determined in a tissue section by means of HE staining which traced the damaged hindbrain. Then, genome-wide approaches for monitoring either the upregulation of apoptotic-related genes (11.8%) or the downregulation of brain development-related genes (29%) at the 24 hpf stage were implemented. The P53/caspase-8-mediated apoptotic death pathway was strongly involved, with the pathway being strongly reversed in a p53 mutant (P53M214K) line during Bad knockdown. Furthermore, we propose the involvement of a p53-mediated stress signal which is correlated with regulating Bad loss-mediated brain defects. We found that some major genes in brain development, such as crybb1, pva1b5, irx4a, pax7a, and fabp7a, were dramatically restored in the P53M214K line, and brain development recovered to return movement behavior to normal. Our findings suggest that Bad is required for (PCD) control, exerting a P53 stress signal on caspase-8/tBid-mediated death signaling and brain development-related gene regulation.

Download Full-text

Unravelling the plant signalling machinery: an update on the cellular and genetic basis of plant signal transduction

Functional Plant Biology ◽

10.1071/fp17085 ◽

2018 ◽

Vol 45 (2) ◽

pp. 1 ◽

Cited By ~ 7

Author(s):

Vadim Demidchik ◽

Frans Maathuis ◽

Olga Voitsekhovskaja

Keyword(s):

Cell Death ◽

Plasma Membrane ◽

Programmed Cell Death ◽

Cyclic Nucleotide ◽

Hydraulic Pressure ◽

Major Theme ◽

Long Distance ◽

Nadph Oxidases ◽

Biochemical Basis ◽

Plant Signal Transduction

Plant signalling is a set of phenomena that serves the transduction of external and internal signals into physiological responses such as modification of enzyme activity, cytoskeleton structure or gene expression. It operates at the level of cell compartments, whole cells, tissues, organs or even plant communities. To achieve this, plants have evolved a network of signalling proteins including plasma membrane receptors and ion transporters, cascades of kinases and other enzymes as well as several second messengers such as cytosolic calcium (Ca2+), reactive oxygen/nitrogen species (ROS/RNS), cyclic nucleotides (cAMP and cGMP) and others. Overall, these systems recognise and decode environmental signals and co-ordinate ontogeny programs. This paper summarises recent progress in the field of plant signalling, which was a major theme of the 4th International Symposium on Plant Signalling and Behaviour, 2016, in Saint Petersburg, Russia. Several novel hypotheses and concepts were proposed during this meeting. First, the concept of ROS-Ca2+ hubs has found further evidence and acceptance. This concept is based on reciprocal activation of NADPH oxidases by cytosolic Ca2+ on the one hand, and Ca2+-permeable channels that are activated by NADPH-produced ROS. ROS-Ca2+ hubs enhance the intensity and duration of originally weak Ca2+ and ROS signals. Hubs are directly involved in ROS- and Ca2+-mediated physiological reactions, such as stress response, growth, programmed cell death, autophagy and long-distance signalling. Second, recent findings have widened the list of cyclic nucleotide-regulated processes and strengthened the biochemical basis of cyclic nucleotide biochemistry by exploring cyclase activities of new receptors such as the Phytosulfokine Receptor 1, the pathogen peptide 1 receptor (atPepR1), the brassinosteroid BRI1 receptor and the cell wall-associated kinase like 10. cGMP and cAMP signalling has demonstrated strong link to Ca2+ signalling, via cyclic nucleotide-gated Ca2+-permeable ion channels (CNGCs), and to ROS and RNS via their nitrosylated forms. Third, a novel role for cytosolic K+ as a regulator of plant autophagy and programmed cell death has emerged. The cell death-associated proteases and endonucleases were demonstrated to be activated by a decrease of cytosolic K+ via ROS-induced stimulation of the plasma membrane K+ efflux channel GORK. Importantly, the origin of ROS for induction of autophagy and cell death varies in different tissues and comprises several pools, including NADPH oxidases, peroxidases, photosynthetic and respiratory electron-transporting chains and peroxisomal enzymes. The peroxisome pool is the ‘latest’ addition to established cellular ROS-producing machineries and is dependent on the state and abundance of catalase in this compartment. Finally, new aspects of phytohormone signalling, such as regulation of root hydraulic pressure by abscisic acid and rate of mitosis by cytokinins, as well as localising cytokinin receptors in endoplasmic reticulum, are reported. Other observations suggest that melatonin is a hormone-like substance in plants, because it targets Ca2+, ROS and RNS.

Download Full-text

Minority potassium-uptake system Trk2 has a crucial role in yeast survival of glucose-induced cell death

Microbiology ◽

10.1099/mic.0.001065 ◽

2021 ◽

Vol 167 (6) ◽

Author(s):

Michala Dušková ◽

Denis Cmunt ◽

Klára Papoušková ◽

Jakub Masaryk ◽

Hana Sychrová

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Death ◽

Plasma Membrane ◽

Programmed Cell Death ◽

Potassium Uptake ◽

Uptake System ◽

Physiological Processes ◽

Highly Sensitive ◽

Dividing Cells ◽

New Finding

The existence of programmed cell death in Saccharomyces cerevisiae has been reported for many years. Glucose induces the death of S. cerevisiae in the absence of additional nutrients within a few hours, and the absence of active potassium uptake makes cells highly sensitive to this process. S. cerevisiae cells possess two transporters, Trk1 and Trk2, which ensure a high intracellular concentration of potassium, necessary for many physiological processes. Trk1 is the major system responsible for potassium acquisition in growing and dividing cells. The contribution of Trk2 to potassium uptake in growing cells is almost negligible, but Trk2 becomes crucial for stationary cells for their survival of some stresses, e.g. anhydrobiosis. As a new finding, we show that both Trk systems contribute to the relative thermotolerance of S. cerevisiae BY4741. Our results also demonstrate that Trk2 is much more important for the cell survival of glucose-induced cell death than Trk1, and that stationary cells deficient in active potassium uptake lose their ATP stocks more rapidly than cells with functional Trk systems. This is probably due to the upregulated activity of plasma-membrane Pma1 H+-ATPase, and consequently, it is the reason why these cells die earlier than cells with functional active potassium uptake.

Download Full-text

Cell death in Porifera: molecular players in the game of apoptotic cell death in living fossils

Canadian Journal of Zoology ◽

10.1139/z05-165 ◽

2006 ◽

Vol 84 (2) ◽

pp. 307-321 ◽

Cited By ~ 24

Author(s):

M Wiens ◽

W E.G Müller

Keyword(s):

Cell Death ◽

Programmed Cell Death ◽

Apoptotic Cell ◽

Molecular Signaling ◽

Regeneration Capacity ◽

The Past ◽

Physiological Processes ◽

Living Fossils ◽

Core Components ◽

Apoptotic Pathways

Apoptosis represents the morphological manifestation of programmed cell death and, paradoxically at first sight, it is a prerequisite for metazoan life. Thus, apoptosis is responsible for the demise of cells during many physiological processes. It is also accountable for the death of cells following exposure to countless stimuli. Therefore, it is obvious that apoptosis must be regulated by a complex network of various molecular signaling pathways. Research during the past 20 years has led to the identification of major functional groups of molecules involved in apoptotic pathways. These include members of the Bcl-2 superfamily, members of the TNF family, caspases, and their activators. Yet, the evolutionary conservation of those elements of the apoptotic machinery was only established from nematode to man. Sponges (phylum Porifera) are characterized by a remarkable regeneration capacity and longevity. Furthermore, they represent the phylogenetically oldest still extant metazoan taxon. Thus, research on these living fossils opens a window to the past, to the dawn of metazoan life. It allows us to trace the evolution of programmed cell death and its core components. This review summarizes the key findings and concepts which have emerged from studies of apoptosis in Porifera.

Download Full-text

The JASMONATE ZIM-DOMAIN family proteins are the important node in jasmonic acid-abscisic acid crosstalk in regulating plant response to drought

Current Protein and Peptide Science ◽

10.2174/1389203722666211018114443 ◽

2021 ◽

Vol 22 ◽

Author(s):

Aarti Gupta ◽

Mamta Bhardwaj ◽

Lam-Son Phan Tran

Keyword(s):

Abscisic Acid ◽

Jasmonic Acid ◽

Biological Processes ◽

Plant Tolerance ◽

Adaptive Responses ◽

Domain Family ◽

Physiological Processes ◽

Jaz Proteins ◽

Ja Signaling ◽

Insight Into

: Plants modulate the metabolism of phytohormones and their signaling pathways under drought to regulate physiological and adaptive responses. Jasmonic acid (JA) is one of the major classes of phytohormones and has been found to potentially enhance plant tolerance to various abiotic stresses, including drought. The JASMONATE ZIM-DOMAIN (JAZ) proteins are the negative regulators in the JA-signaling pathway. The JAZ protein family is explicit to plants and involved in the regulation of numerous biological processes, including drought-responsive mechanisms. In this review, we synthesize the mechanistic insight into the roles of JAZ proteins in regulation of drought responses by connecting the JA-signaling with abscisic acid-signaling to modulate drought-responsive physiological processes.

Download Full-text