1
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Tyagi A, Ali S, Park S, Bae H. Deciphering the role of mechanosensitive channels in plant root biology: perception, signaling, and adaptive responses. PLANTA 2023; 258:105. [PMID: 37878056 DOI: 10.1007/s00425-023-04261-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/02/2023] [Indexed: 10/26/2023]
Abstract
MAIN CONCLUSION Mechanosensitive channels are integral membrane proteins that rapidly translate extrinsic or intrinsic mechanical tensions into biological responses. They can serve as potential candidates for developing smart-resilient crops with efficient root systems. Mechanosensitive (MS) calcium channels are molecular switches for mechanoperception and signal transduction in all living organisms. Although tremendous progress has been made in understanding mechanoperception and signal transduction in bacteria and animals, this remains largely unknown in plants. However, identification and validation of MS channels such as Mid1-complementing activity channels (MCAs), mechanosensitive-like channels (MSLs), and Piezo channels (PIEZO) has been the most significant discovery in plant mechanobiology, providing novel insights into plant mechanoperception. This review summarizes recent advances in root mechanobiology, focusing on MS channels and their related signaling players, such as calcium ions (Ca2+), reactive oxygen species (ROS), and phytohormones. Despite significant advances in understanding the role of Ca2+ signaling in root biology, little is known about the involvement of MS channel-driven Ca2+ and ROS signaling. Additionally, the hotspots connecting the upstream and downstream signaling of MS channels remain unclear. In light of this, we discuss the present knowledge of MS channels in root biology and their role in root developmental and adaptive traits. We also provide a model highlighting upstream (cell wall sensors) and downstream signaling players, viz., Ca2+, ROS, and hormones, connected with MS channels. Furthermore, we highlighted the importance of emerging signaling molecules, such as nitric oxide (NO), hydrogen sulfide (H2S), and neurotransmitters (NTs), and their association with root mechanoperception. Finally, we conclude with future directions and knowledge gaps that warrant further research to decipher the complexity of root mechanosensing.
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Affiliation(s)
- Anshika Tyagi
- Department of Biotechnology, Yeungnam University, Gyeongsan Gyeongbuk, 38541, Republic of Korea.
| | - Sajad Ali
- Department of Biotechnology, Yeungnam University, Gyeongsan Gyeongbuk, 38541, Republic of Korea
| | - Suvin Park
- Department of Biotechnology, Yeungnam University, Gyeongsan Gyeongbuk, 38541, Republic of Korea
| | - Hanhong Bae
- Department of Biotechnology, Yeungnam University, Gyeongsan Gyeongbuk, 38541, Republic of Korea.
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2
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Zhang J, Maksaev G, Yuan P. Open structure and gating of the Arabidopsis mechanosensitive ion channel MSL10. Nat Commun 2023; 14:6284. [PMID: 37805510 PMCID: PMC10560256 DOI: 10.1038/s41467-023-42117-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Accepted: 09/29/2023] [Indexed: 10/09/2023] Open
Abstract
Plants are challenged by drastically different osmotic environments during growth and development. Adaptation to these environments often involves mechanosensitive ion channels that can detect and respond to mechanical force. In the model plant Arabidopsis thaliana, the mechanosensitive channel MSL10 plays a crucial role in hypo-osmotic shock adaptation and programmed cell death induction, but the molecular basis of channel function remains poorly understood. Here, we report a structural and electrophysiological analysis of MSL10. The cryo-electron microscopy structures reveal a distinct heptameric channel assembly. Structures of the wild-type channel in detergent and lipid environments, and in the absence of membrane tension, capture an open conformation. Furthermore, structural analysis of a non-conductive mutant channel demonstrates that reorientation of phenylalanine side chains alone, without main chain rearrangements, may generate the hydrophobic gate. Together, these results reveal a distinct gating mechanism and advance our understanding of mechanotransduction.
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Affiliation(s)
- Jingying Zhang
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, USA
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Grigory Maksaev
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, USA
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, USA.
- Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, USA.
- Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
- Department of Neuroscience, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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3
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Zhang Z, Ye F, Xiong T, Chen J, Cao J, Chen Y, Liu S. Origin, evolution and diversification of plant mechanosensitive channel of small conductance-like (MSL) proteins. BMC PLANT BIOLOGY 2023; 23:462. [PMID: 37794319 PMCID: PMC10552396 DOI: 10.1186/s12870-023-04479-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Accepted: 09/20/2023] [Indexed: 10/06/2023]
Abstract
Mechanosensitive (MS) ion channels provide efficient molecular mechanism for transducing mechanical forces into intracellular ion fluxes in all kingdoms of life. The mechanosensitive channel of small conductance (MscS) was one of the best-studied MS channels and its homologs (MSL, MscS-like) were widely distributed in cell-walled organisms. However, the origin, evolution and expansion of MSL proteins in plants are still not clear. Here, we identified more than 2100 MSL proteins from 176 plants and conducted a broad-scale phylogenetic analysis. The phylogenetic tree showed that plant MSL proteins were divided into three groups (I, II and III) prior to the emergence of chlorophytae algae, consistent with their specific subcellular localization. MSL proteins were distributed unevenly into each of plant species, and four parallel expansion was identified in angiosperms. In Brassicaceae, most MSL duplicates were derived by whole-genome duplication (WGD)/segmental duplications. Finally, a hypothetical evolutionary model of MSL proteins in plants was proposed based on phylogeny. Our studies illustrate the evolutionary history of the MSL proteins and provide a guide for future functional diversity analyses of these proteins in plants.
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Affiliation(s)
- Zaibao Zhang
- School of Life and Health Science, Huzhou College, Huzhou, Zhejiang, China.
| | - Fan Ye
- College of International Education, Xinyang Normal University, Xinyang, Henan, China
| | - Tao Xiong
- College of Life Science, Xinyang Normal University, Xinyang, Henan, China
| | - Jiahui Chen
- College of International Education, Xinyang Normal University, Xinyang, Henan, China
| | - Jiajia Cao
- College of International Education, Xinyang Normal University, Xinyang, Henan, China
| | - Yurui Chen
- College of International Education, Xinyang Normal University, Xinyang, Henan, China
| | - Sushuang Liu
- School of Life and Health Science, Huzhou College, Huzhou, Zhejiang, China
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4
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Hsia CR, Melters DP, Dalal Y. The Force is Strong with This Epigenome: Chromatin Structure and Mechanobiology. J Mol Biol 2023; 435:168019. [PMID: 37330288 PMCID: PMC10567996 DOI: 10.1016/j.jmb.2023.168019] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Revised: 02/13/2023] [Accepted: 02/15/2023] [Indexed: 06/19/2023]
Abstract
All life forms sense and respond to mechanical stimuli. Throughout evolution, organisms develop diverse mechanosensing and mechanotransduction pathways, leading to fast and sustained mechanoresponses. Memory and plasticity characteristics of mechanoresponses are thought to be stored in the form of epigenetic modifications, including chromatin structure alterations. These mechanoresponses in the chromatin context share conserved principles across species, such as lateral inhibition during organogenesis and development. However, it remains unclear how mechanotransduction mechanisms alter chromatin structure for specific cellular functions, and if altered chromatin structure can mechanically affect the environment. In this review, we discuss how chromatin structure is altered by environmental forces via an outside-in pathway for cellular functions, and the emerging concept of how chromatin structure alterations can mechanically affect nuclear, cellular, and extracellular environments. This bidirectional mechanical feedback between chromatin of the cell and the environment can potentially have important physiological implications, such as in centromeric chromatin regulation of mechanobiology in mitosis, or in tumor-stroma interactions. Finally, we highlight the current challenges and open questions in the field and provide perspectives for future research.
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Affiliation(s)
- Chieh-Ren Hsia
- Chromatin Structure and Epigenetic Mechanisms, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, NCI, NIH, Bethesda, MD, United States. https://twitter.com/JeremiahHsia
| | - Daniël P Melters
- Chromatin Structure and Epigenetic Mechanisms, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, NCI, NIH, Bethesda, MD, United States. https://twitter.com/dpmelters
| | - Yamini Dalal
- Chromatin Structure and Epigenetic Mechanisms, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, NCI, NIH, Bethesda, MD, United States. https://twitter.com/NCIYaminiDalal
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5
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Park YC, Reddy B, Bavi N, Perozo E, Faraldo-Gómez JD. State-specific morphological deformations of the lipid bilayer explain mechanosensitive gating of MscS ion channels. eLife 2023; 12:81445. [PMID: 36715097 PMCID: PMC9925053 DOI: 10.7554/elife.81445] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Accepted: 01/22/2023] [Indexed: 01/31/2023] Open
Abstract
The force-from-lipids hypothesis of cellular mechanosensation posits that membrane channels open and close in response to changes in the physical state of the lipid bilayer, induced for example by lateral tension. Here, we investigate the molecular basis for this transduction mechanism by studying the mechanosensitive ion channel MscS from Escherichia coli and its eukaryotic homolog MSL1 from Arabidopsis thaliana. First, we use single-particle cryo-electron microscopy to determine the structure of a novel open conformation of wild-type MscS, stabilized in a thinned lipid nanodisc. Compared with the closed state, the structure shows a reconfiguration of helices TM1, TM2, and TM3a, and widening of the central pore. Based on these structures, we examined how the morphology of the membrane is altered upon gating, using molecular dynamics simulations. The simulations reveal that closed-state MscS causes drastic protrusions in the inner leaflet of the lipid bilayer, both in the absence and presence of lateral tension, and for different lipid compositions. These deformations arise to provide adequate solvation to hydrophobic crevices under the TM1-TM2 hairpin, and clearly reflect a high-energy conformation for the membrane, particularly under tension. Strikingly, these protrusions are largely eradicated upon channel opening. An analogous computational study of open and closed MSL1 recapitulates these findings. The gating equilibrium of MscS channels thus appears to be dictated by opposing conformational preferences, namely those of the lipid membrane and of the protein structure. We propose a membrane deformation model of mechanosensation, which posits that tension shifts the gating equilibrium towards the conductive state not because it alters the mode in which channel and lipids interact, but because it increases the energetic cost of the morphological perturbations in the membrane required by the closed state.
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Affiliation(s)
- Yein Christina Park
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
| | - Bharat Reddy
- Department of Biochemistry and Molecular Biology, University of ChicagoChicagoUnited States
| | - Navid Bavi
- Department of Biochemistry and Molecular Biology, University of ChicagoChicagoUnited States
| | - Eduardo Perozo
- Department of Biochemistry and Molecular Biology, University of ChicagoChicagoUnited States
| | - José D Faraldo-Gómez
- Theoretical Molecular Biophysics Laboratory, National Heart, Lung and Blood Institute, National Institutes of HealthBethesdaUnited States
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6
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Nakayama Y, Rohde PR, Martinac B. "Force-From-Lipids" Dependence of the MscCG Mechanosensitive Channel Gating on Anionic Membranes. Microorganisms 2023; 11:microorganisms11010194. [PMID: 36677485 PMCID: PMC9861469 DOI: 10.3390/microorganisms11010194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/15/2023] Open
Abstract
Mechanosensory transduction in Corynebacterium glutamicum plays a major role in glutamate efflux for industrial MSG, whose production depends on the activation of MscCG-type mechanosensitive channels. Dependence of the MscCG channel activation by membrane tension on the membrane lipid content has to date not been functionally characterized. Here, we report the MscCG channel patch clamp recording from liposomes fused with C. glutamicum membrane vesicles as well as from proteoliposomes containing the purified MscCG protein. Our recordings demonstrate that mechanosensitivity of MscCG channels depends significantly on the presence of negatively charged lipids in the proteoliposomes. MscCG channels in liposome preparations fused with native membrane vesicles exhibited the activation threshold similar to the channels recorded from C. glutamicum giant spheroplasts. In comparison, the activation threshold of the MscCG channels reconstituted into azolectin liposomes was higher than the activation threshold of E. coli MscL, which is gated by membrane tension close to the bilayer lytic tension. The spheroplast-like activation threshold was restored when the MscCG channels were reconstituted into liposomes made of E. coli polar lipid extract. In liposomes made of polar lipids mixed with synthetic phosphatidylethanolamine, phosphatidylglycerol, and cardiolipin, the activation threshold of MscCG was significantly reduced compared to the activation threshold recorded in azolectin liposomes, which suggests the importance of anionic lipids for the channel mechanosensitivity. Moreover, the micropipette aspiration technique combined with patch fluorometry demonstrated that membranes containing anionic phosphatidylglycerol are softer than membranes containing only polar non-anionic phosphatidylcholine and phosphatidylethanolamine. The difference in mechanosensitivity between C. glutamicum MscCG and canonical MscS of E. coli observed in proteoliposomes explains the evolutionary tuning of the force from lipids sensing in various bacterial membrane environments.
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Affiliation(s)
- Yoshitaka Nakayama
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
- Faculty of Medicine, St Vincent’s Clinical School, The University of New South Wales, Sydney 2010, Australia
| | - Paul R. Rohde
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
| | - Boris Martinac
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney 2010, Australia
- Faculty of Medicine, St Vincent’s Clinical School, The University of New South Wales, Sydney 2010, Australia
- Correspondence: ; Tel.: +61-2-9295-8743
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7
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Zhao Y, Gao S, Song D, Ye Z, Xu R, Luo Y, Xu Q. Lipidoid Artificial Compartments for Bidirectional Regulation of Enzyme Activity through Nanomechanical Action. J Am Chem Soc 2023; 145:551-559. [PMID: 36537880 DOI: 10.1021/jacs.2c11004] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Photoresponsive inhibitor and noninhibitor systems have been developed to achieve on-demand enzyme activity control. However, inhibitors are only effective for a specific and narrow range of enzymes. Noninhibitor systems usually require mutation and modification of the enzymes, leading to irreversible loss of enzymatic activities. Inspired by biological membranes, we herein report a lipidoid-based artificial compartment composed of azobenzene (Azo) lipidoids and helper lipids, which can bidirectionally regulate the activity of the encapsulated enzymes by light. In this system, the reversible photoisomerization of Azo lipidoids triggered by UV/vis light creates a continuous rotation-inversion movement, thereby enhancing the permeability of the compartment membrane and allowing substrates to pass through. Moreover, the membrane can revert to its impermeable state when light is removed. Thus, enzyme activity can be switched on and off when encapsulating enzymes in the compartments. Importantly, since neither mutation nor modification is required, negligible loss of activity is observed for the encapsulated enzymes after repeated activation and inhibition. Furthermore, this approach provides a generic strategy for controlling multiple enzymes by forgoing the use of inhibitors and may broaden the applications of enzymes in biological mechanism research and precision medicine.
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Affiliation(s)
- Yu Zhao
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Shuliang Gao
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Donghui Song
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Zhongfeng Ye
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Ruijie Xu
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Ying Luo
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Qiaobing Xu
- Department of Biomedical Engineering, Tufts University, Medford, Massachusetts 02155, United States
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8
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Flegler VJ, Rasmussen T, Böttcher B. How Functional Lipids Affect the Structure and Gating of Mechanosensitive MscS-like Channels. Int J Mol Sci 2022; 23:ijms232315071. [PMID: 36499396 PMCID: PMC9739000 DOI: 10.3390/ijms232315071] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/21/2022] [Accepted: 11/23/2022] [Indexed: 12/04/2022] Open
Abstract
The ability to cope with and adapt to changes in the environment is essential for all organisms. Osmotic pressure is a universal threat when environmental changes result in an imbalance of osmolytes inside and outside the cell which causes a deviation from the normal turgor. Cells have developed a potent system to deal with this stress in the form of mechanosensitive ion channels. Channel opening releases solutes from the cell and relieves the stress immediately. In bacteria, these channels directly sense the increased membrane tension caused by the enhanced turgor levels upon hypoosmotic shock. The mechanosensitive channel of small conductance, MscS, from Escherichia coli is one of the most extensively studied examples of mechanically stimulated channels. Different conformational states of this channel were obtained in various detergents and membrane mimetics, highlighting an intimate connection between the channel and its lipidic environment. Associated lipids occupy distinct locations and determine the conformational states of MscS. Not all these features are preserved in the larger MscS-like homologues. Recent structures of homologues from bacteria and plants identify common features and differences. This review discusses the current structural and functional models for MscS opening, as well as the influence of certain membrane characteristics on gating.
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9
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Mount J, Maksaev G, Summers BT, Fitzpatrick JAJ, Yuan P. Structural basis for mechanotransduction in a potassium-dependent mechanosensitive ion channel. Nat Commun 2022; 13:6904. [PMID: 36371466 PMCID: PMC9653487 DOI: 10.1038/s41467-022-34737-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 11/04/2022] [Indexed: 11/13/2022] Open
Abstract
Mechanosensitive channels of small conductance, found in many living organisms, open under elevated membrane tension and thus play crucial roles in biological response to mechanical stress. Amongst these channels, MscK is unique in that its activation also requires external potassium ions. To better understand this dual gating mechanism by force and ligand, we elucidate distinct structures of MscK along the gating cycle using cryo-electron microscopy. The heptameric channel comprises three layers: a cytoplasmic domain, a periplasmic gating ring, and a markedly curved transmembrane domain that flattens and expands upon channel opening, which is accompanied by dilation of the periplasmic ring. Furthermore, our results support a potentially unifying mechanotransduction mechanism in ion channels depicted as flattening and expansion of the transmembrane domain.
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Affiliation(s)
- Jonathan Mount
- grid.4367.60000 0001 2355 7002Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO USA
| | - Grigory Maksaev
- grid.4367.60000 0001 2355 7002Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO USA
| | - Brock T. Summers
- grid.4367.60000 0001 2355 7002Washington University Center for Cellular Imaging, Washington University School of Medicine, Saint Louis, MO USA
| | - James A. J. Fitzpatrick
- grid.4367.60000 0001 2355 7002Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Washington University Center for Cellular Imaging, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO USA
| | - Peng Yuan
- grid.4367.60000 0001 2355 7002Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO USA ,grid.4367.60000 0001 2355 7002Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO USA
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10
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Louf JF, Alexander SLM. Poroelastic plant-inspired structures & materials to sense, regulate flow, and move. BIOINSPIRATION & BIOMIMETICS 2022; 18:015002. [PMID: 36317663 DOI: 10.1088/1748-3190/ac9e32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Despite their lack of a nervous system and muscles, plants are able to feel, regulate flow, and move. Such abilities are achieved through complex multi-scale couplings between biology, chemistry, and physics, making them difficult to decipher. A promising approach is to decompose plant responses in different blocks that can be modeled independently, and combined later on for a more holistic view. In this perspective, we examine the most recent strategies for designing plant-inspired soft devices that leverage poroelastic principles to sense, manipulate flow, and even generate motion. We will start at the organism scale, and study how plants can use poroelasticity to carry informationin-lieuof a nervous system. Then, we will go down in size and look at how plants manage to passively regulate flow at the microscopic scale using valves with encoded geometric non-linearities. Lastly, we will see at an even smaller scale, at the nanoscopic scale, how fibers orientation in plants' tissues allow them to induce motion using water instead of muscles.
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Affiliation(s)
- Jean-François Louf
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, United States of America
| | - Symone L M Alexander
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, United States of America
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11
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Jiang W, Tong T, Chen X, Deng F, Zeng F, Pan R, Zhang W, Chen G, Chen ZH. Molecular response and evolution of plant anion transport systems to abiotic stress. PLANT MOLECULAR BIOLOGY 2022; 110:397-412. [PMID: 34846607 DOI: 10.1007/s11103-021-01216-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 10/31/2021] [Indexed: 06/13/2023]
Abstract
We propose that anion channels are essential players for green plants to respond and adapt to the abiotic stresses associated changing climate via reviewing the literature and analyzing the molecular evolution, comparative genetic analysis, and bioinformatics analysis of the key anion channel gene families. Climate change-induced abiotic stresses including heatwave, elevated CO2, drought, and flooding, had a major impact on plant growth in the last few decades. This scenario could lead to the exposure of plants to various stresses. Anion channels are confirmed as the key factors in plant stress responses, which exist in the green lineage plants. Numerous studies on anion channels have shed light on their protein structure, ion selectivity and permeability, gating characteristics, and regulatory mechanisms, but a great quantity of questions remain poorly understand. Here, we review function of plant anion channels in cell signaling to improve plant response to environmental stresses, focusing on climate change related abiotic stresses. We investigate the molecular response and evolution of plant slow anion channel, aluminum-activated malate transporter, chloride channel, voltage-dependent anion channel, and mechanosensitive-like anion channel in green plant. Furthermore, comparative genetic and bioinformatic analysis reveal the conservation of these anion channel gene families. We also discuss the tissue and stress specific expression, molecular regulation, and signaling transduction of those anion channels. We propose that anion channels are essential players for green plants to adapt in a diverse environment, calling for more fundamental and practical studies on those anion channels towards sustainable food production and ecosystem health in the future.
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Affiliation(s)
- Wei Jiang
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Tao Tong
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Xuan Chen
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Fenglin Deng
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Fanrong Zeng
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Rui Pan
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Wenying Zhang
- Hubei Collaborative Innovation Center for Grain Industry, College of Agriculture, Yangtze University, Jingzhou, China
| | - Guang Chen
- Central Laboratory, Zhejiang Academy of Agricultural Science, Hangzhou, China.
| | - Zhong-Hua Chen
- School of Science, Western Sydney University, Penrith, NSW, Australia.
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia.
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12
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Guichard M, Thomine S, Frachisse JM. Mechanotransduction in the spotlight of mechano-sensitive channels. CURRENT OPINION IN PLANT BIOLOGY 2022; 68:102252. [PMID: 35772372 DOI: 10.1016/j.pbi.2022.102252] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Revised: 05/06/2022] [Accepted: 05/26/2022] [Indexed: 06/15/2023]
Abstract
The study of mechanosensitive channels (MS) in living organisms has progressed considerably over the past two decades. The understanding of their roles in mechanosensation and mechanotransduction was consecrated by the awarding of the Nobel Prize in 2021 to A. Patapoutian for his discoveries on the role of MS channels in mechanoperception in humans. In this review, we first summarize the fundamental properties of MS channels and their mode of operation. Then in a second step, we provide an update on the knowledge on the families of MS channels identified in plants and the roles and functions that have been attributed to them.
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Affiliation(s)
- Marjorie Guichard
- Institute of Cell and Interaction Biology, Heinrich-Heine-University Düsseldorf, Universitätsstraße 1, 40225 Düsseldorf, Germany
| | - Sébastien Thomine
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France
| | - Jean-Marie Frachisse
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), 91198, Gif-sur-Yvette, France.
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13
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Cooper RL, Thomas MA, McLetchie DN. Impedance Measures for Detecting Electrical Responses during Acute Injury and Exposure of Compounds to Roots of Plants. Methods Protoc 2022; 5:mps5040056. [PMID: 35893582 PMCID: PMC9351684 DOI: 10.3390/mps5040056] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Revised: 06/19/2022] [Accepted: 06/23/2022] [Indexed: 11/16/2022] Open
Abstract
Electrical activity is widely used for assessing a plant's response to an injury or environmental stimulus. Commonly, a differential electrode recording between silver wire leads with the reference wire connected to the soil, or a part of the plant, is used. One method uses KCl-filled glass electrodes placed into the plant, similar to recording membrane/cell potentials in animal tissues. This method is more susceptible to artifacts of equipment noise and photoelectric effects than an impedance measure. An impedance measure using stainless steel wires is not as susceptible to electrically induced noises. Impedance measurements are able to detect injury in plants as well as exposure of the roots to environmental compounds (glutamate). The impedance measures were performed in 5 different plants (tomato, eggplant, pepper, liverwort, and Coleus scutellarioides), and responses to mechanical movement of the plant, as well as injury, were recorded. Monitoring electrical activity in a plant that arises in a distant plant was also demonstrated using the impedance method. The purpose of this report is to illustrate the ease in using impedance measures for monitoring electrical signals from individual plants or aggregates of plants for potentially scaling for high throughput and monitoring controlled culturing and outdoor field environments.
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14
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Spatiotemporal stop-and-go dynamics of the mitochondrial TOM core complex correlates with channel activity. Commun Biol 2022; 5:471. [PMID: 35581327 PMCID: PMC9114391 DOI: 10.1038/s42003-022-03419-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Accepted: 04/26/2022] [Indexed: 11/08/2022] Open
Abstract
Single-molecule studies can reveal phenomena that remain hidden in ensemble measurements. Here we show the correlation between lateral protein diffusion and channel activity of the general protein import pore of mitochondria (TOM-CC) in membranes resting on ultrathin hydrogel films. Using electrode-free optical recordings of ion flux, we find that TOM-CC switches reversibly between three states of ion permeability associated with protein diffusion. While freely diffusing TOM-CC molecules are predominantly in a high permeability state, non-mobile molecules are mostly in an intermediate or low permeability state. We explain this behavior by the mechanical binding of the two protruding Tom22 subunits to the hydrogel and a concomitant combinatorial opening and closing of the two β-barrel pores of TOM-CC. TOM-CC could thus represent a β-barrel membrane protein complex to exhibit membrane state-dependent mechanosensitive properties, mediated by its two Tom22 subunits.
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15
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Structural insights into the Venus flytrap mechanosensitive ion channel Flycatcher1. Nat Commun 2022; 13:850. [PMID: 35165281 PMCID: PMC8844309 DOI: 10.1038/s41467-022-28511-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 01/27/2022] [Indexed: 12/23/2022] Open
Abstract
Flycatcher1 (FLYC1), a MscS homolog, has recently been identified as a candidate mechanosensitive (MS) ion channel involved in Venus flytrap prey recognition. FLYC1 is a larger protein and its sequence diverges from previously studied MscS homologs, suggesting it has unique structural features that contribute to its function. Here, we characterize FLYC1 by cryo-electron microscopy, molecular dynamics simulations, and electrophysiology. Akin to bacterial MscS and plant MSL1 channels, we find that FLYC1 central core includes side portals in the cytoplasmic cage that regulate ion preference and conduction, by identifying critical residues that modulate channel conductance. Topologically unique cytoplasmic flanking regions can adopt ‘up’ or ‘down’ conformations, making the channel asymmetric. Disruption of an up conformation-specific interaction severely delays channel deactivation by 40-fold likely due to stabilization of the channel open state. Our results illustrate novel structural features and likely conformational transitions that regulate mechano-gating of FLYC1. Flycatcher1 (FLYC1) is a candidate mechanosensitive channel involved in Venus flytrap touch-induced prey capture. Here, the authors report structural and functional details of FLYC1, with insights into gating conformational transitions.
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16
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Codjoe JM, Miller K, Haswell ES. Plant cell mechanobiology: Greater than the sum of its parts. THE PLANT CELL 2022; 34:129-145. [PMID: 34524447 PMCID: PMC8773992 DOI: 10.1093/plcell/koab230] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 09/09/2021] [Indexed: 05/04/2023]
Abstract
The ability to sense and respond to physical forces is critical for the proper function of cells, tissues, and organisms across the evolutionary tree. Plants sense gravity, osmotic conditions, pathogen invasion, wind, and the presence of barriers in the soil, and dynamically integrate internal and external stimuli during every stage of growth and development. While the field of plant mechanobiology is growing, much is still poorly understood-including the interplay between mechanical and biochemical information at the single-cell level. In this review, we provide an overview of the mechanical properties of three main components of the plant cell and the mechanoperceptive pathways that link them, with an emphasis on areas of complexity and interaction. We discuss the concept of mechanical homeostasis, or "mechanostasis," and examine the ways in which cellular structures and pathways serve to maintain it. We argue that viewing mechanics and mechanotransduction as emergent properties of the plant cell can be a useful conceptual framework for synthesizing current knowledge and driving future research.
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Affiliation(s)
- Jennette M Codjoe
- Department of Biology and Center for Engineering Mechanobiology, Washington University in St Louis, St Louis, Missouri, 63130, USA
| | - Kari Miller
- Department of Biology and Center for Engineering Mechanobiology, Washington University in St Louis, St Louis, Missouri, 63130, USA
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17
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Böhm J, Scherzer S. Signaling and transport processes related to the carnivorous lifestyle of plants living on nutrient-poor soil. PLANT PHYSIOLOGY 2021; 187:2017-2031. [PMID: 35235668 PMCID: PMC8890503 DOI: 10.1093/plphys/kiab297] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2021] [Accepted: 06/04/2021] [Indexed: 05/29/2023]
Abstract
In Eukaryotes, long-distance and rapid signal transmission is required in order to be able to react fast and flexibly to external stimuli. This long-distance signal transmission cannot take place by diffusion of signal molecules from the site of perception to the target tissue, as their speed is insufficient. Therefore, for adequate stimulus transmission, plants as well as animals make use of electrical signal transmission, as this can quickly cover long distances. This update summarises the most important advances in plant electrical signal transduction with a focus on the carnivorous Venus flytrap. It highlights the different types of electrical signals, examines their underlying ion fluxes and summarises the carnivorous processes downstream of the electrical signals.
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Affiliation(s)
- Jennifer Böhm
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, 97082 Würzburg, Germany
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Würzburg, 97082 Würzburg, Germany
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18
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Moe-Lange J, Gappel NM, Machado M, Wudick MM, Sies CSA, Schott-Verdugo SN, Bonus M, Mishra S, Hartwig T, Bezrutczyk M, Basu D, Farmer EE, Gohlke H, Malkovskiy A, Haswell ES, Lercher MJ, Ehrhardt DW, Frommer WB, Kleist TJ. Interdependence of a mechanosensitive anion channel and glutamate receptors in distal wound signaling. SCIENCE ADVANCES 2021; 7:eabg4298. [PMID: 34516872 PMCID: PMC8442888 DOI: 10.1126/sciadv.abg4298] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Glutamate has dual roles in metabolism and signaling; thus, signaling functions must be isolatable and distinct from metabolic fluctuations, as seen in low-glutamate domains at synapses. In plants, wounding triggers electrical and calcium (Ca2+) signaling, which involve homologs of mammalian glutamate receptors. The hydraulic dispersal and squeeze-cell hypotheses implicate pressure as a key component of systemic signaling. Here, we identify the stretch-activated anion channel MSL10 as necessary for proper wound-induced electrical and Ca2+ signaling. Wound gene induction, genetics, and Ca2+ imaging indicate that MSL10 acts in the same pathway as the glutamate receptor–like proteins (GLRs). Analogous to mammalian NMDA glutamate receptors, GLRs may serve as coincidence detectors gated by the combined requirement for ligand binding and membrane depolarization, here mediated by stretch activation of MSL10. This study provides a molecular genetic basis for a role of mechanical signal perception and the transmission of long-distance electrical and Ca2+ signals in plants.
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Affiliation(s)
- Jacob Moe-Lange
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Department of Plant Biology, Carnegie Science, Stanford, CA 94305, USA
| | - Nicoline M. Gappel
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Mackenzie Machado
- Department of Plant Biology, Carnegie Science, Stanford, CA 94305, USA
| | - Michael M. Wudick
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Cosima S. A. Sies
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Stephan N. Schott-Verdugo
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Centro de Bioinformática y Simulación Molecular (CBSM), Facultad de Ingeniería, Universidad de Talca, 2 Norte 685, CL-3460000 Talca, Chile
- John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Bioinformatics), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52425 Jülich, Germany
| | - Michele Bonus
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Swastik Mishra
- Computational Cell Biology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Thomas Hartwig
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Margaret Bezrutczyk
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - Debarati Basu
- NSF Center for Engineering Mechanobiology, Department of Biology, Washington University in St. Louis, Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
| | - Edward E. Farmer
- Department of Plant Molecular Biology, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Holger Gohlke
- Institute for Pharmaceutical and Medicinal Chemistry, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- John von Neumann Institute for Computing (NIC), Jülich Supercomputing Centre (JSC), Institute of Biological Information Processing (IBI-7: Structural Bioinformatics), and Institute of Bio- and Geosciences (IBG-4: Bioinformatics), Forschungszentrum Jülich GmbH, Wilhelm-Johnen-Str., 52425 Jülich, Germany
| | - Andrey Malkovskiy
- Department of Plant Biology, Carnegie Science, Stanford, CA 94305, USA
| | - Elizabeth S. Haswell
- NSF Center for Engineering Mechanobiology, Department of Biology, Washington University in St. Louis, Box 1137, One Brookings Drive, St. Louis, MO 63130, USA
| | - Martin J. Lercher
- Computational Cell Biology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
| | - David W. Ehrhardt
- Department of Plant Biology, Carnegie Science, Stanford, CA 94305, USA
| | - Wolf B. Frommer
- Department of Biology, Stanford University, Stanford, CA 94305, USA
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
- Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8601, Japan
- Corresponding author.
| | - Thomas J. Kleist
- Institute for Molecular Physiology, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany
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19
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Behnami S, Bonetta D. With an Ear Up against the Wall: An Update on Mechanoperception in Arabidopsis. PLANTS (BASEL, SWITZERLAND) 2021; 10:1587. [PMID: 34451632 PMCID: PMC8398075 DOI: 10.3390/plants10081587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 07/26/2021] [Accepted: 07/28/2021] [Indexed: 11/16/2022]
Abstract
Cells interpret mechanical signals and adjust their physiology or development appropriately. In plants, the interface with the outside world is the cell wall, a structure that forms a continuum with the plasma membrane and the cytoskeleton. Mechanical stress from cell wall damage or deformation is interpreted to elicit compensatory responses, hormone signalling, or immune responses. Our understanding of how this is achieved is still evolving; however, we can refer to examples from animals and yeast where more of the details have been worked out. Here, we provide an update on this changing story with a focus on candidate mechanosensitive channels and plasma membrane-localized receptors.
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Affiliation(s)
| | - Dario Bonetta
- Faculty of Science, Ontario Tech University, 2000 Simcoe St N, Oshawa, ON L1G 0C5, Canada;
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20
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Dindas J, Dreyer I, Huang S, Hedrich R, Roelfsema MRG. A voltage-dependent Ca 2+ homeostat operates in the plant vacuolar membrane. THE NEW PHYTOLOGIST 2021; 230:1449-1460. [PMID: 33577135 DOI: 10.1111/nph.17272] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 02/05/2021] [Indexed: 06/12/2023]
Abstract
Cytosolic calcium signals are evoked by a large variety of biotic and abiotic stimuli and play an important role in cellular and long distance signalling in plants. While the function of the plasma membrane in cytosolic Ca2+ signalling has been intensively studied, the role of the vacuolar membrane remains elusive. A newly developed vacuolar voltage clamp technique was used in combination with live-cell imaging, to study the role of the vacuolar membrane in Ca2+ and pH homeostasis of bulging root hair cells of Arabidopsis. Depolarisation of the vacuolar membrane caused a rapid increase in the Ca2+ concentration and alkalised the cytosol, while hyperpolarisation led to the opposite responses. The relationship between the vacuolar membrane potential, the cytosolic pH and Ca2+ concentration suggests that a vacuolar H+ /Ca2+ exchange mechanism plays a central role in cytosolic Ca2+ homeostasis. Mathematical modelling further suggests that the voltage-dependent vacuolar Ca2+ homeostat could contribute to calcium signalling when coupled to a recently discovered K+ channel-dependent module for electrical excitability of the vacuolar membrane.
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Affiliation(s)
- Julian Dindas
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Würzburg, D-97082, Germany
- Institute of Plant and Microbial Biology and Zürich-Basel Plant Science Center, University of Zürich, Zollikerstrasse 107, Zürich, CH-8008, Switzerland
| | - Ingo Dreyer
- Center of Bioinformatics, Simulation and Modeling (CBSM), Faculty of Engineering, Universidad de Talca, 2 Norte 685, Talca, 3460000, Chile
| | - Shouguang Huang
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Würzburg, D-97082, Germany
| | - Rainer Hedrich
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Würzburg, D-97082, Germany
| | - M Rob G Roelfsema
- Molecular Plant Physiology and Biophysics, Julius-von-Sachs Institute for Biosciences, Biocenter, Würzburg University, Würzburg, D-97082, Germany
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21
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Nakayama Y. Corynebacterium glutamicum Mechanosensing: From Osmoregulation to L-Glutamate Secretion for the Avian Microbiota-Gut-Brain Axis. Microorganisms 2021; 9:201. [PMID: 33478007 PMCID: PMC7835871 DOI: 10.3390/microorganisms9010201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/15/2021] [Accepted: 01/18/2021] [Indexed: 12/18/2022] Open
Abstract
After the discovery of Corynebacterium glutamicum from avian feces-contaminated soil, its enigmatic L-glutamate secretion by corynebacterial MscCG-type mechanosensitive channels has been utilized for industrial monosodium glutamate production. Bacterial mechanosensitive channels are activated directly by increased membrane tension upon hypoosmotic downshock; thus; the physiological significance of the corynebacterial L-glutamate secretion has been considered as adjusting turgor pressure by releasing cytoplasmic solutes. In this review, we present information that corynebacterial mechanosensitive channels have been evolutionally specialized as carriers to secrete L-glutamate into the surrounding environment in their habitats rather than osmotic safety valves. The lipid modulation activation of MscCG channels in L-glutamate production can be explained by the "Force-From-Lipids" and "Force-From-Tethers" mechanosensing paradigms and differs significantly from mechanical activation upon hypoosmotic shock. The review also provides information on the search for evidence that C. glutamicum was originally a gut bacterium in the avian host with the aim of understanding the physiological roles of corynebacterial mechanosensing. C. glutamicum is able to secrete L-glutamate by mechanosensitive channels in the gut microbiota and help the host brain function via the microbiota-gut-brain axis.
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Affiliation(s)
- Yoshitaka Nakayama
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Darlinghurst, NSW 2010, Australia; ; Tel.: +61-2-9295-8744
- St Vincent’s Clinical School, Faculty of Medicine, The University of New South Wales, Darlinghurst, NSW 2010, Australia
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22
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Discoveries in structure and physiology of mechanically activated ion channels. Nature 2020; 587:567-576. [PMID: 33239794 DOI: 10.1038/s41586-020-2933-1] [Citation(s) in RCA: 258] [Impact Index Per Article: 64.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Accepted: 08/19/2020] [Indexed: 01/24/2023]
Abstract
The ability to sense physical forces is conserved across all organisms. Cells convert mechanical stimuli into electrical or chemical signals via mechanically activated ion channels. In recent years, the identification of new families of mechanosensitive ion channels-such as PIEZO and OSCA/TMEM63 channels-along with surprising insights into well-studied mechanosensitive channels have driven further developments in the mechanotransduction field. Several well-characterized mechanosensory roles such as touch, blood-pressure sensing and hearing are now linked with primary mechanotransducers. Unanticipated roles of mechanical force sensing continue to be uncovered. Furthermore, high-resolution structures representative of nearly every family of mechanically activated channel described so far have underscored their diversity while advancing our understanding of the biophysical mechanisms of pressure sensing. Here we summarize recent discoveries in the physiology and structures of known mechanically activated ion channel families and discuss their implications for understanding the mechanisms of mechanical force sensing.
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23
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Schlegel AM, Haswell ES. Charged pore-lining residues are required for normal channel kinetics in the eukaryotic mechanosensitive ion channel MSL1. Channels (Austin) 2020; 14:310-325. [PMID: 32988273 PMCID: PMC7757850 DOI: 10.1080/19336950.2020.1818509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
Mechanosensitive (MS) ion channels are widespread mechanisms for cellular mechanosensation that can be directly activated by increasing membrane tension. The well-studied MscS family of MS ion channels is found in bacteria, archaea, and plants. MscS-Like (MSL)1 is localized to the inner mitochondrial membrane of Arabidopsis thaliana, where it is required for normal mitochondrial responses to oxidative stress. Like Escherichia coli MscS, MSL1 has a pore-lining helix that is kinked. However, in MSL1 this kink is comprised of two charged pore-lining residues, R326 and D327. Using single-channel patch-clamp electrophysiology in E. coli, we show that altering the size and charge of R326 and D327 leads to dramatic changes in channel kinetics. Modest changes in gating pressure were also observed while no effects on channel rectification or conductance were detected. MSL1 channel variants had differing physiological function in E. coli hypoosmotic shock assays, without clear correlation between function and particular channel characteristics. Taken together, these results demonstrate that altering pore-lining residue charge and size disrupts normal channel state stability and gating transitions, and led us to propose the “sweet spot” model. In this model, the transition to the closed state is facilitated by attraction between R326 and D327 and repulsion between R326 residues of neighboring monomers. In the open state, expansion of the channel reduces inter-monomeric repulsion, rendering open state stability influenced mainly by attractive forces. This work provides insight into how unique charge-charge interactions can be combined with an otherwise conserved structural feature to help modulate MS channel function.
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Affiliation(s)
- Angela M Schlegel
- Department of Biology, Washington University , St. Louis, Missouri, USA.,NSF Center for Engineering Mechanobiology, Washington University , St. Louis, Missouri, USA
| | - Elizabeth S Haswell
- Department of Biology, Washington University , St. Louis, Missouri, USA.,NSF Center for Engineering Mechanobiology, Washington University , St. Louis, Missouri, USA
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24
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Deng Z, Maksaev G, Schlegel AM, Zhang J, Rau M, Fitzpatrick JAJ, Haswell ES, Yuan P. Structural mechanism for gating of a eukaryotic mechanosensitive channel of small conductance. Nat Commun 2020; 11:3690. [PMID: 32704140 PMCID: PMC7378837 DOI: 10.1038/s41467-020-17538-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 07/07/2020] [Indexed: 01/21/2023] Open
Abstract
Mechanosensitive ion channels transduce physical force into electrochemical signaling that underlies an array of fundamental physiological processes, including hearing, touch, proprioception, osmoregulation, and morphogenesis. The mechanosensitive channels of small conductance (MscS) constitute a remarkably diverse superfamily of channels critical for management of osmotic pressure. Here, we present cryo-electron microscopy structures of a MscS homolog from Arabidopsis thaliana, MSL1, presumably in both the closed and open states. The heptameric MSL1 channel contains an unusual bowl-shaped transmembrane region, which is reminiscent of the evolutionarily and architecturally unrelated mechanosensitive Piezo channels. Upon channel opening, the curved transmembrane domain of MSL1 flattens and expands. Our structures, in combination with functional analyses, delineate a structural mechanism by which mechanosensitive channels open under increased membrane tension. Further, the shared structural feature between unrelated channels suggests the possibility of a unified mechanical gating mechanism stemming from membrane deformation induced by a non-planar transmembrane domain. Mechanosensitive channels transduce physical force into electrochemical signaling in processes such as hearing, touch, proprioception, osmoregulation, and morphogenesis. Here, authors use cryo-electron microscopy to provide structural insights into the mechanical gating mechanism.
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Affiliation(s)
- Zengqin Deng
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Grigory Maksaev
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Angela M Schlegel
- Department of Biology, Washington University in Saint Louis, Saint Louis, MO, 63130, USA.,NSF Center for Engineering Mechanobiology, Washington University in Saint Louis, Saint Louis, MO, 63130, USA
| | - Jingying Zhang
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - Michael Rau
- Washington University Center for Cellular Imaging, Washington University School of Medicine, Saint Louis, MO, 63110, USA
| | - James A J Fitzpatrick
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Washington University Center for Cellular Imaging, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Department of Neuroscience, Washington University School of Medicine, Saint Louis, MO, 63110, USA.,Department of Biomedical Engineering, Washington University in Saint Louis, Saint Louis, MO, 63130, USA
| | - Elizabeth S Haswell
- Department of Biology, Washington University in Saint Louis, Saint Louis, MO, 63130, USA.,NSF Center for Engineering Mechanobiology, Washington University in Saint Louis, Saint Louis, MO, 63130, USA
| | - Peng Yuan
- Department of Cell Biology and Physiology, Washington University School of Medicine, Saint Louis, MO, 63110, USA. .,Center for the Investigation of Membrane Excitability Diseases, Washington University School of Medicine, Saint Louis, MO, 63110, USA.
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25
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Channels and transporters for inorganic ions in plant mitochondria: Prediction and facts. Mitochondrion 2020; 53:224-233. [PMID: 32540403 DOI: 10.1016/j.mito.2020.05.007] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 05/01/2020] [Accepted: 05/22/2020] [Indexed: 02/07/2023]
Abstract
Mitochondria are crucial bioenergetic organelles for providing different metabolites, including ATP, to sustain cell growth both in animals and in plants. These organelles, delimited by two membranes (outer and inner mitochondrial membrane), maintain their function by an intensive communication with other organelles as well as with the cytosol. Transport of metabolites across the two membranes, but also that of inorganic ions, takes place through specific ion channels and transporters and plays a crucial role in ensuring an adequate ionic milieu within the mitochondria. In the present review we briefly summarize the current knowledge about plant mitochondrial ion channels and transporters in comparison to those of animal mitochondria and examine the possible molecular identity of the so far unidentified transport systems taking into account subcellular targeting predictions and data from literature.
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