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Zhang M, Tang C, Li Y, Lv S, Xie Z, Liu Z, Zhang H, Zhang S, Wang P, Wu J. The MYC transcription factor PbrMYC8 negatively regulates PbrMSL5 expression to promote pollen germination in Pyrus. Int J Biol Macromol 2024; 278:134640. [PMID: 39142484 DOI: 10.1016/j.ijbiomac.2024.134640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2024] [Revised: 07/22/2024] [Accepted: 08/08/2024] [Indexed: 08/16/2024]
Abstract
The successful germination of pollen is essential for double fertilization in flowering plants. Mechanosensitive channels of small conductance (MscS-like, MSL) inhibit pollen germination and maintains cellular integrity of pollen during this process. Therefore, it is vital to carefully regulate the expression of MSL to promote successful pollen germination. Despite its importance, the molecular mechanisms governing MSL expression in plants remain poorly understood. Here, we had identified 15 MSL genes in the pear, among which PbrMSL5 was expressed in pollen development. Subcellular localization experiments revealed that PbrMSL5 was located in both plasma membrane and cytoplasm. Functional investigations, including complementation experiments using the atmsl8 mutant background, demonstrated the involvement of PbrMSL5 in preserving pollen cell integrity and inhibiting germination. Antisense oligonucleotide experiments further confirmed that PbrMSL5 suppressed pear pollen germination by reducing osmotic pressure and Cl- content. Yeast one-hybrid, electrophoretic mobility shift assays, and dual luciferase reporter assay elucidated that PbrMYC8 interacts directly with the N-box element, leading to the suppression of PbrMSL5 expression and promoted pollen germination. These results represented a significant advancement in unraveling the molecular mechanisms controlling plant MSL expression. This study showed valuable contribution to advancing our comprehension of the mechanism underlying pollen germination.
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Affiliation(s)
- Mingliang Zhang
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Chao Tang
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Yu Li
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shouzheng Lv
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Zhu Xie
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Zongqi Liu
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Hao Zhang
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Shaoling Zhang
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China
| | - Peng Wang
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China.
| | - Juyou Wu
- Sanya Institute of Nanjing Agricultural University, State Key Laboratory of Crop Genetics & Germplasm Enhancement and Utilization, Jiangsu Key Laboratory for Horticultural Crop Breeding, College of Horticulture, Nanjing Agricultural University, Nanjing 210095, China; Zhongshan Biological Breeding Laboratory, No.50 Zhongling Street, Nanjing, Jiangsu 210014, China.
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2
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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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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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Flynn AJ, Miller K, Codjoe JM, King MR, Haswell ES. Mechanosensitive ion channels MSL8, MSL9, and MSL10 have environmentally sensitive intrinsically disordered regions with distinct biophysical characteristics in vitro. PLANT DIRECT 2023; 7:e515. [PMID: 37547488 PMCID: PMC10400277 DOI: 10.1002/pld3.515] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/26/2023] [Accepted: 06/27/2023] [Indexed: 08/08/2023]
Abstract
Intrinsically disordered protein regions (IDRs) are highly dynamic sequences that rapidly sample a collection of conformations over time. In the past several decades, IDRs have emerged as a major component of many proteomes, comprising ~30% of all eukaryotic protein sequences. Proteins with IDRs function in a wide range of biological pathways and are notably enriched in signaling cascades that respond to environmental stresses. Here, we identify and characterize intrinsic disorder in the soluble cytoplasmic N-terminal domains of MSL8, MSL9, and MSL10, three members of the MscS-like (MSL) family of mechanosensitive ion channels. In plants, MSL channels are proposed to mediate cell and organelle osmotic homeostasis. Bioinformatic tools unanimously predicted that the cytosolic N-termini of MSL channels are intrinsically disordered. We examined the N-terminus of MSL10 (MSL10N) as an exemplar of these IDRs and circular dichroism spectroscopy confirms its disorder. MSL10N adopted a predominately helical structure when exposed to the helix-inducing compound trifluoroethanol (TFE). Furthermore, in the presence of molecular crowding agents, MSL10N underwent structural changes and exhibited alterations to its homotypic interaction favorability. Lastly, interrogations of collective behavior via in vitro imaging of condensates indicated that MSL8N, MSL9N, and MSL10N have sharply differing propensities for self-assembly into condensates, both inherently and in response to salt, temperature, and molecular crowding. Taken together, these data establish the N-termini of MSL channels as intrinsically disordered regions with distinct biophysical properties and the potential to respond uniquely to changes in their physiochemical environment.
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Affiliation(s)
- Aidan J. Flynn
- Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
- NSF Center for Engineering Mechanobiology, Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
- Department of Biochemistry and BiophysicsWashington University in St. LouisSt. LouisMissouriUSA
| | - Kari Miller
- Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
- NSF Center for Engineering Mechanobiology, Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
| | - Jennette M. Codjoe
- Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
- NSF Center for Engineering Mechanobiology, Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
| | - Matthew R. King
- Department of Biomedical EngineeringWashington University in St. LouisSt. LouisMissouriUSA
| | - Elizabeth S. Haswell
- Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
- NSF Center for Engineering Mechanobiology, Department of BiologyWashington University in St. LouisSt. LouisMissouriUSA
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5
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The Course of Mechanical Stress: Types, Perception, and Plant Response. BIOLOGY 2023; 12:biology12020217. [PMID: 36829495 PMCID: PMC9953051 DOI: 10.3390/biology12020217] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 01/31/2023]
Abstract
Mechanical stimuli, together with the corresponding plant perception mechanisms and the finely tuned thigmomorphogenetic response, has been of scientific and practical interest since the mid-17th century. As an emerging field, there are many challenges in the research of mechanical stress. Indeed, studies on different plant species (annual/perennial) and plant organs (stem/root) using different approaches (field, wet lab, and in silico/computational) have delivered insufficient findings that frequently impede the practical application of the acquired knowledge. Accordingly, the current work distils existing mechanical stress knowledge by bringing in side-by-side the research conducted on both stem and roots. First, the various types of mechanical stress encountered by plants are defined. Second, plant perception mechanisms are outlined. Finally, the different strategies employed by the plant stem and roots to counteract the perceived mechanical stresses are summarized, depicting the corresponding morphological, phytohormonal, and molecular characteristics. The comprehensive literature on both perennial (woody) and annual plants was reviewed, considering the potential benefits and drawbacks of the two plant types, which allowed us to highlight current gaps in knowledge as areas of interest for future research.
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6
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Kordyum EL, Artemenko OA, Hasenstein KH. Lipid Rafts and Plant Gravisensitivity. Life (Basel) 2022; 12:1809. [PMID: 36362962 PMCID: PMC9695138 DOI: 10.3390/life12111809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 10/30/2022] [Accepted: 11/02/2022] [Indexed: 07/24/2023] Open
Abstract
The necessity to include plants as a component of a Bioregenerative Life Support System leads to investigations to optimize plant growth facilities as well as a better understanding of the plant cell membrane and its numerous activities in the signaling, transport, and sensing of gravity, drought, and other stressors. The cell membrane participates in numerous processes, including endo- and exocytosis and cell division, and is involved in the response to external stimuli. Variable but stabilized microdomains form in membranes that include specific lipids and proteins that became known as (detergent-resistant) membrane microdomains, or lipid rafts with various subclassifications. The composition, especially the sterol-dependent recruitment of specific proteins affects endo- and exo-membrane domains as well as plasmodesmata. The enhanced saturated fatty acid content in lipid rafts after clinorotation suggests increased rigidity and reduced membrane permeability as a primary response to abiotic and mechanical stress. These results can also be obtained with lipid-sensitive stains. The linkage of the CM to the cytoskeleton via rafts is part of the complex interactions between lipid microdomains, mechanosensitive ion channels, and the organization of the cytoskeleton. These intricately linked structures and functions provide multiple future research directions to elucidate the role of lipid rafts in physiological processes.
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Affiliation(s)
- Elizabeth L. Kordyum
- Department of Cell Biology and Anatomy, Institute of Botany NASU, Tereschenkivska Str. 2, 01601 Kyiv, Ukraine
| | - Olga A. Artemenko
- Department of Cell Biology and Anatomy, Institute of Botany NASU, Tereschenkivska Str. 2, 01601 Kyiv, Ukraine
| | - Karl H. Hasenstein
- Biology Department, University of Louisiana at Lafayette, Lafayette, LA 70504-3602, USA
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7
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Park CJ, Shin R. Calcium channels and transporters: Roles in response to biotic and abiotic stresses. FRONTIERS IN PLANT SCIENCE 2022; 13:964059. [PMID: 36161014 PMCID: PMC9493244 DOI: 10.3389/fpls.2022.964059] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Accepted: 08/22/2022] [Indexed: 06/16/2023]
Abstract
Calcium (Ca2+) serves as a ubiquitous second messenger by mediating various signaling pathways and responding to numerous environmental conditions in eukaryotes. Therefore, plant cells have developed complex mechanisms of Ca2+ communication across the membrane, receiving the message from their surroundings and transducing the information into cells and organelles. A wide range of biotic and abiotic stresses cause the increase in [Ca2+]cyt as a result of the Ca2+ influx permitted by membrane-localized Ca2+ permeable cation channels such as CYCLIC NUCLEOTIDE-GATE CHANNELs (CNGCs), and voltage-dependent HYPERPOLARIZATION-ACTIVATED CALCIUM2+ PERMEABLE CHANNELs (HACCs), as well as GLUTAMATE RECEPTOR-LIKE RECEPTORs (GLRs) and TWO-PORE CHANNELs (TPCs). Recently, resistosomes formed by some NUCLEOTIDE-BINDING LEUCINE-RICH REPEAT RECEPTORs (NLRs) are also proposed as a new type of Ca2+ permeable cation channels. On the contrary, some Ca2+ transporting membrane proteins, mainly Ca2+-ATPase and Ca2+/H+ exchangers, are involved in Ca2+ efflux for removal of the excessive [Ca2+]cyt in order to maintain the Ca2+ homeostasis in cells. The Ca2+ efflux mechanisms mediate the wide ranges of cellular activities responding to external and internal stimuli. In this review, we will summarize and discuss the recent discoveries of various membrane proteins involved in Ca2+ influx and efflux which play an essential role in fine-tuning the processing of information for plant responses to abiotic and biotic stresses.
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Affiliation(s)
- Chang-Jin Park
- Department of Bioresources Engineering, Sejong University, Seoul, South Korea
| | - Ryoung Shin
- RIKEN Center for Sustainable Resource Science, Yokohama, Japan
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8
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Gorgues L, Li X, Maurel C, Martinière A, Nacry P. Root osmotic sensing from local perception to systemic responses. STRESS BIOLOGY 2022; 2:36. [PMID: 37676549 PMCID: PMC10442022 DOI: 10.1007/s44154-022-00054-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/28/2022] [Indexed: 09/08/2023]
Abstract
Plants face a constantly changing environment, requiring fine tuning of their growth and development. Plants have therefore developed numerous mechanisms to cope with environmental stress conditions. One striking example is root response to water deficit. Upon drought (which causes osmotic stress to cells), plants can among other responses alter locally their root system architecture (hydropatterning) or orientate their root growth to optimize water uptake (hydrotropism). They can also modify their hydraulic properties, metabolism and development coordinately at the whole root and plant levels. Upstream of these developmental and physiological changes, plant roots must perceive and transduce signals for water availability. Here, we review current knowledge on plant osmotic perception and discuss how long distance signaling can play a role in signal integration, leading to the great phenotypic plasticity of roots and plant development.
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Affiliation(s)
- Lucille Gorgues
- IPSiM, CNRS, INRAE, Institut Agro, Univ Montpellier, 34060 Montpellier, France
| | - Xuelian Li
- IPSiM, CNRS, INRAE, Institut Agro, Univ Montpellier, 34060 Montpellier, France
| | - Christophe Maurel
- IPSiM, CNRS, INRAE, Institut Agro, Univ Montpellier, 34060 Montpellier, France
| | | | - Philippe Nacry
- IPSiM, CNRS, INRAE, Institut Agro, Univ Montpellier, 34060 Montpellier, France
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9
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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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10
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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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11
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Kaur A, Taneja M, Tyagi S, Sharma A, Singh K, Upadhyay SK. Genome-wide characterization and expression analysis suggested diverse functions of the mechanosensitive channel of small conductance-like (MSL) genes in cereal crops. Sci Rep 2020; 10:16583. [PMID: 33024170 PMCID: PMC7538590 DOI: 10.1038/s41598-020-73627-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 09/21/2020] [Indexed: 11/23/2022] Open
Abstract
Mechanosensitive ion channels are pore-forming transmembrane proteins that allow ions to move down their electrochemical gradient in response to mechanical stimuli. They participate in many plant developmental processes including the maintenance of plastid shape, pollen tube growth, etc. Herein, a total of 11, 10, 6, 30, 9, and 8 MSL genes were identified in Aegilops tauschii, Hordeum vulgare, Sorghum bicolor, Triticum aestivum, Triticum urartu, and Zea mays, respectively. These genes were located on various chromosomes of their respective cereal, while MSLs of T. urartu were found on scaffolds. The phylogenetic analysis, subcellular localization, and sequence homology suggested clustering of MSLs into two classes. These genes consisted of cis-regulatory elements related to growth and development, responsive to light, hormone, and stress. Differential expression of various MSL genes in tissue developmental stages and stress conditions revealed their precise role in development and stress responses. Altered expression during CaCl2 stress suggested their role in Ca2+ homeostasis and signaling. The co-expression analysis suggested their interactions with other genes involved in growth, defense responses etc. A comparative expression profiling of paralogous genes revealed either retention of function or pseudo-functionalization. The present study unfolded various characteristics of MSLs in cereals, which will facilitate their in-depth functional characterization in future studies.
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Affiliation(s)
- Amandeep Kaur
- Department of Botany, Panjab University, Chandigarh, 160014, India
| | - Mehak Taneja
- Department of Botany, Panjab University, Chandigarh, 160014, India
| | - Shivi Tyagi
- Department of Botany, Panjab University, Chandigarh, 160014, India
| | - Alok Sharma
- Department of Botany, Panjab University, Chandigarh, 160014, India
| | - Kashmir Singh
- Department of Biotechnology, Panjab University, Chandigarh, 160014, India
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12
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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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13
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Cox CD, Bavi N, Martinac B. Biophysical Principles of Ion-Channel-Mediated Mechanosensory Transduction. Cell Rep 2020; 29:1-12. [PMID: 31577940 DOI: 10.1016/j.celrep.2019.08.075] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 06/09/2019] [Accepted: 08/22/2019] [Indexed: 01/12/2023] Open
Abstract
Recent rapid progress in the field of mechanobiology has been driven by novel emerging tools and methodologies and growing interest from different scientific disciplines. Specific progress has been made toward understanding how cell mechanics is linked to intracellular signaling and the regulation of gene expression in response to a variety of mechanical stimuli. There is a direct link between the mechanoreceptors at the cell surface and intracellular biochemical signaling, which in turn controls downstream effector molecules. Among the mechanoreceptors in the cell membrane, mechanosensitive (MS) ion channels are essential for the ultra-rapid (millisecond) transduction of mechanical stimuli into biologically relevant signals. The three decades of research on mechanosensitive channels resulted in the formulation of two basic principles of mechanosensitive channel gating: force-from-lipids and force-from-filament. In this review, we revisit the biophysical principles that underlie the innate force-sensing ability of mechanosensitive channels as contributors to the force-dependent evolution of life forms.
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Affiliation(s)
- Charles D Cox
- Victor Chang Cardiac Research Institute, Lowy Packer Building, Darlinghurst, NSW 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW 2010, Australia
| | - Navid Bavi
- Institute for Biophysical Dynamics, University of Chicago, Chicago, IL 60637, USA
| | - Boris Martinac
- Victor Chang Cardiac Research Institute, Lowy Packer Building, Darlinghurst, NSW 2010, Australia; St. Vincent's Clinical School, University of New South Wales, Darlinghurst, NSW 2010, Australia.
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14
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The Plasma Membrane-An Integrating Compartment for Mechano-Signaling. PLANTS 2020; 9:plants9040505. [PMID: 32295309 PMCID: PMC7238056 DOI: 10.3390/plants9040505] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Revised: 04/11/2020] [Accepted: 04/12/2020] [Indexed: 12/30/2022]
Abstract
Plants are able to sense their mechanical environment. This mechanical signal is used by the plant to determine its phenotypic features. This is true also at a smaller scale. Morphogenesis, both at the cell and tissue level, involves mechanical signals that influence specific patterns of gene expression and trigger signaling pathways. How a mechanical stress is perceived and how this signal is transduced into the cell remains a challenging question in the plant community. Among the structural components of plant cells, the plasma membrane has received very little attention. Yet, its position at the interface between the cell wall and the interior of the cell makes it a key factor at the nexus between biochemical and mechanical cues. So far, most of the key players that are described to perceive and maintain mechanical cell status and to respond to a mechanical stress are localized at or close to the plasma membrane. In this review, we will focus on the importance of the plasma membrane in mechano-sensing and try to illustrate how the composition of this dynamic compartment is involved in the regulatory processes of a cell to respond to mechanical stress.
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15
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Li Y, Hu Y, Wang J, Liu X, Zhang W, Sun L. Structural Insights into a Plant Mechanosensitive Ion Channel MSL1. Cell Rep 2020; 30:4518-4527.e3. [DOI: 10.1016/j.celrep.2020.03.026] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/16/2020] [Accepted: 03/10/2020] [Indexed: 02/08/2023] Open
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16
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Frachisse JM, Thomine S, Allain JM. Calcium and plasma membrane force-gated ion channels behind development. CURRENT OPINION IN PLANT BIOLOGY 2020; 53:57-64. [PMID: 31783322 DOI: 10.1016/j.pbi.2019.10.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/17/2019] [Accepted: 10/21/2019] [Indexed: 06/10/2023]
Abstract
During development, tissues are submitted to high variation of compression and tension forces. The roles of the cell wall, the cytoskeleton, the turgor pressure and the cell geometry during this process have received due attention. In contrast, apart from its role in the establishment of turgor pressure, the involvement of the plasma membrane as a transducer of mechanical forces during development has been under studied. Force-gated (FG) or Mechanosensitive (MS) ion channels embedded in the bilayer represent 'per se' archetypal mechanosensor able to directly and instantaneously transduce membrane forces into electrical and calcium signals. We discuss here how their fine-tuning, combined with their ability to detect micro-curvature and local membrane tension, allows FG channels to transduce mechanical cues into developmental signals.
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Affiliation(s)
- Jean-Marie Frachisse
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Sciences Plant Saclay, 91198 Gif sur Yvette Cedex, France.
| | - Sébastien Thomine
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Sciences Plant Saclay, 91198 Gif sur Yvette Cedex, France
| | - Jean-Marc Allain
- LMS, CNRS, Ecole Polytechnique, Institut Polytechnique de Paris, Palaiseau, France; Inria, Palaiseau, France.
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17
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Lee JS, Wilson ME, Richardson RA, Haswell ES. Genetic and physical interactions between the organellar mechanosensitive ion channel homologs MSL1, MSL2, and MSL3 reveal a role for inter-organellar communication in plant development. PLANT DIRECT 2019; 3:e00124. [PMID: 31245767 PMCID: PMC6508831 DOI: 10.1002/pld3.124] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 01/24/2019] [Accepted: 02/11/2019] [Indexed: 05/31/2023]
Abstract
Plant development requires communication on many levels, including between cells and between organelles within a cell. For example, mitochondria and plastids have been proposed to be sensors of environmental stress and to coordinate their responses. Here we present evidence for communication between mitochondria and chloroplasts during leaf and root development, based on genetic and physical interactions between three Mechanosensitive channel of Small conductance-Like (MSL) proteins from Arabidopsis thaliana. MSL proteins are Arabidopsis homologs of the bacterial Mechanosensitive channel of Small conductance (MscS), which relieves cellular osmotic pressure to protect against lysis during hypoosmotic shock. MSL1 localizes to the inner mitochondrial membrane, while MSL2 and MSL3 localize to the inner plastid membrane and are required to maintain plastid osmotic homeostasis during normal growth and development. In this study, we characterized the phenotypic effect of a genetic lesion in MSL1, both in wild type and in msl2 msl3 mutant backgrounds. msl1 single mutants appear wild type for all phenotypes examined. The characteristic leaf rumpling in msl2 msl3 double mutants was exacerbated in the msl1 msl2 msl3 triple mutant. However, the introduction of the msl1 lesion into the msl2 msl3 mutant background suppressed other msl2 msl3 mutant phenotypes, including ectopic callus formation, accumulation of superoxide and hydrogen peroxide in the shoot apical meristem, decreased root length, and reduced number of lateral roots. All these phenotypes could be recovered by molecular complementation with a transgene containing a wild type version of MSL1. In yeast-based interaction studies, MSL1 interacted with itself, but not with MSL2 or MSL3. These results establish that the abnormalities observed in msl2 msl3 double mutants is partially dependent on the presence of functional MSL1 and suggest a possible role for communication between plastid and mitochondria in seedling development.
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Affiliation(s)
- Josephine S. Lee
- NSF Center for Engineering MechanoBiologyDepartment of BiologyWashington University in Saint LouisSaint LouisMissouri
- Present address:
Broad InstituteCambridgeMassachusetts
| | - Margaret E. Wilson
- NSF Center for Engineering MechanoBiologyDepartment of BiologyWashington University in Saint LouisSaint LouisMissouri
- Present address:
Donald Danforth Plant Science CenterSaint LouisMissouri
| | - Ryan A. Richardson
- NSF Center for Engineering MechanoBiologyDepartment of BiologyWashington University in Saint LouisSaint LouisMissouri
| | - Elizabeth S. Haswell
- NSF Center for Engineering MechanoBiologyDepartment of BiologyWashington University in Saint LouisSaint LouisMissouri
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18
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Zhang Z, Tong X, Liu SY, Chai LX, Zhu FF, Zhang XP, Zou JZ, Wang XB. Genetic analysis of a Piezo-like protein suppressing systemic movement of plant viruses in Arabidopsis thaliana. Sci Rep 2019; 9:3187. [PMID: 30816193 PMCID: PMC6395819 DOI: 10.1038/s41598-019-39436-3] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 01/24/2019] [Indexed: 01/01/2023] Open
Abstract
As obligate intracellular phytopathogens, plant viruses must take advantage of hosts plasmodesmata and phloem vasculature for their local and long-distance transports to establish systemic infection in plants. In contrast to well-studied virus local transports, molecular mechanisms and related host genes governing virus systemic trafficking are far from being understood. Here, we performed a forward genetic screening to identify Arabidopsis thaliana mutants with enhanced susceptibility to a 2b-deleted mutant of cucumber mosaic virus (CMV-2aT∆2b). We found that an uncharacterized Piezo protein (AtPiezo), an ortholog of animal Piezo proteins with mechanosensitive (MS) cation channel activities, was required for inhibiting systemic infection of CMV-2aT∆2b and turnip mosaic virus tagged a green fluorescent protein (GFP) (TuMV-GFP). AtPiezo is induced by virus infection, especially in the petioles of rosette leaves. Thus, we for the first time demonstrate the biological function of Piezo proteins in plants, which might represent a common antiviral strategy because many monocot and dicot plant species have a single Piezo ortholog.
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Affiliation(s)
- Zhen Zhang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xin Tong
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Song-Yu Liu
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Long-Xiang Chai
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Fei-Fan Zhu
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiao-Peng Zhang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Jing-Ze Zou
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China
| | - Xian-Bing Wang
- State Key Laboratory of Agro-Biotechnology, College of Biological Sciences, China Agricultural University, Beijing, 100193, China.
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19
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Liu X, Wang J, Sun L. Structure of the hyperosmolality-gated calcium-permeable channel OSCA1.2. Nat Commun 2018; 9:5060. [PMID: 30498218 PMCID: PMC6265326 DOI: 10.1038/s41467-018-07564-5] [Citation(s) in RCA: 99] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 11/09/2018] [Indexed: 01/08/2023] Open
Abstract
In plants, hyperosmolality stimuli triggers opening of the osmosensitive channels, leading to a rapid downstream signaling cascade initiated by cytosolic calcium concentration elevation. Members of the OSCA family in Arabidopsis thaliana, identified as the hyperosmolality-gated calcium-permeable channels, have been suggested to play a key role during the initial phase of hyperosmotic stress response. Here, we report the atomic structure of Arabidopsis OSCA1.2 determined by single-particle cryo-electron microscopy. It contains 11 transmembrane helices and forms a homodimer. It is in an inactivated state, and the pore-lining residues are clearly identified. Its cytosolic domain contains a RNA recognition motif and two unique long helices. The linker between these two helices forms an anchor in the lipid bilayer and may be essential to osmosensing. The structure of AtOSCA1.2 serves as a platform for the study of the mechanism underlying osmotic stress responses and mechanosensing. In plants, hyperosmolality stimuli triggers opening of the osmosensitive channels, leading to a rapid downstream signaling cascade. Here, the authors solve the cryo-EM structure of an osmosensitive channel from Arabidopsis OSCA1.2 in its inactivated state.
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Affiliation(s)
- Xin Liu
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, 230027, Hefei, China
| | - Jiawei Wang
- State Key Laboratory of Membrane Biology, Beijing Advanced Innovation Centre for Structural Biology, School of Life Sciences, Tsinghua University, 100084, Beijing, China.
| | - Linfeng Sun
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, 230027, Hefei, China. .,CAS Centre for Excellence in Molecular Cell Science, University of Science and Technology of China, Chinese Academy of Sciences, 230027, Hefei, China.
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20
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Guerringue Y, Thomine S, Frachisse JM. Sensing and transducing forces in plants with MSL10 and DEK1 mechanosensors. FEBS Lett 2018; 592:1968-1979. [PMID: 29782638 DOI: 10.1002/1873-3468.13102] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 04/27/2018] [Accepted: 05/05/2018] [Indexed: 12/14/2022]
Abstract
Mechanosensitive (MS) channels behave as microprobes that transduce mechanical tension into electric and ion signals. The plasma membrane anion-permeable channel AtMSL10 belongs to the first family of MS channels (MscS-LIKE) that has been characterized in Arabidopsis thaliana. In the same membrane, a rapidly activated calcium MS channel activity (RMA) associated with the presence of the DEFECTIVE KERNEL1 (AtDEK1) protein has been recently described. In this Review, based on the comparison of the specific properties of AtMSL10 and RMA, we put forward hypotheses on the mechanism of activation of these two channels, their respective roles in signalling and also raise the question of the molecular identity of RMA. Finally, we propose functions for these two channels within the context of plant mechanotransduction.
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Affiliation(s)
- Yannick Guerringue
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, France
| | - Sébastien Thomine
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, France
| | - Jean-Marie Frachisse
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Université Paris-Sud, Université Paris-Saclay, Gif sur Yvette, France
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21
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Maksaev G, Shoots JM, Ohri S, Haswell ES. Nonpolar residues in the presumptive pore-lining helix of mechanosensitive channel MSL10 influence channel behavior and establish a nonconducting function. PLANT DIRECT 2018; 2:e00059. [PMID: 30506019 PMCID: PMC6261518 DOI: 10.1002/pld3.59] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Mechanosensitive (MS) ion channels provide a universal mechanism for sensing and responding to increased membrane tension. MscS-like (MSL) 10 is a relatively well-studied MS ion channel from Arabidopsis thaliana that is implicated in cell death signaling. The relationship between the amino acid sequence of MSL10 and its conductance, gating tension, and opening and closing kinetics remains unstudied. Here, we identify several nonpolar residues in the presumptive pore-lining transmembrane helix of MSL10 (TM6) that contribute to these basic channel properties. F553 and I554 are essential for wild type channel conductance and the stability of the open state. G556, a glycine residue located at a predicted kink in TM6, is essential for channel conductance. The increased tension sensitivity of MSL10 compared to close homolog MSL8 may be attributed to F563, but other channel characteristics appear to be dictated by more global differences in structure. Finally, MSL10 F553V and MSL10 G556V provided the necessary tools to establish that MSL10's ability to trigger cell death is independent of its ion channel function.
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Affiliation(s)
- Grigory Maksaev
- Department of Biology and Center for Engineering MechanoBiologyWashington University in Saint LouisSaint LouisMissouri
- Present address:
Department of Cell Biology and Physiology and Center for the Investigation of Membrane Excitability DiseasesWashington University School of MedicineSaint LouisMO
| | - Jennette M. Shoots
- Department of Biology and Center for Engineering MechanoBiologyWashington University in Saint LouisSaint LouisMissouri
| | - Simran Ohri
- Department of Biology and Center for Engineering MechanoBiologyWashington University in Saint LouisSaint LouisMissouri
| | - Elizabeth S. Haswell
- Department of Biology and Center for Engineering MechanoBiologyWashington University in Saint LouisSaint LouisMissouri
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22
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A R Webb A, Kuchitsu K, Kwak J, Pei ZM, Iida H. Sensors Make Sense of Signaling. PLANT & CELL PHYSIOLOGY 2017; 58:1121-1125. [PMID: 28838127 DOI: 10.1093/pcp/pcx085] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Affiliation(s)
- Alex A R Webb
- Department of Plant Sciences, University of Cambridge, Downing Street, Cambridge CB3 0LJ, UK
| | - Kazuyuki Kuchitsu
- Department of Applied Biological Science, Faculty of Science, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba-ken 278-8510, Japan
| | - June Kwak
- Center for Plant Aging Research, Institute for Basic Science, Daegu, South Korea
- Department of New Biology, Daegu Gyeongbuk Institute of Science and Technology, 333 Techno-Jungangdaero, Daegu 42988, South Korea
| | - Zhen-Ming Pei
- College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, China
- Department of Biology, Duke University, 124 Science Dr, Durham, NC 27708, USA
| | - Hidetoshi Iida
- Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui Kita-machi, Koganei-shi, Tokyo 184-8501, Japan
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23
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Zou Y, Chintamanani S, He P, Fukushige H, Yu L, Shao M, Zhu L, Hildebrand DF, Tang X, Zhou JM. A gain-of-function mutation in Msl10 triggers cell death and wound-induced hyperaccumulation of jasmonic acid in Arabidopsis. JOURNAL OF INTEGRATIVE PLANT BIOLOGY 2016; 58:600-9. [PMID: 26356550 DOI: 10.1111/jipb.12427] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2014] [Accepted: 09/09/2015] [Indexed: 05/02/2023]
Abstract
Jasmonates (JAs) are rapidly induced after wounding and act as key regulators for wound induced signaling pathway. However, what perceives the wound signal and how that triggers JA biosynthesis remains poorly understood. To identify components involved in Arabidopsis wound and JA signaling pathway, we screened for mutants with abnormal expression of a luciferase reporter, which is under the control of a wound-responsive promoter of an ethylene response factor (ERF) transcription factor gene, RAP2.6 (Related to APetala 2.6). The rea1 (RAP2.6 expresser in shoot apex) mutant constitutively expressed the RAP2.6-LUC reporter gene in young leaves. Along with the typical JA phenotypes including shorter petioles, loss of apical dominance, accumulation of anthocyanin pigments and constitutive expression of JA response gene, rea1 plants also displayed cell death and accumulated high levels of JA in response to wounding. The phenotype of rea1 mutant is caused by a gain-of-function mutation in the C-terminus of a mechanosensitive ion channel MscS-like 10 (MSL10). MSL10 is localized in the plasma membrane and is expressed predominantly in root tip, shoot apex and vascular tissues. These results suggest that MSL10 is involved in the wound-triggered early signal transduction pathway and possibly in regulating the positive feedback synthesis of JA.
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Affiliation(s)
- Yan Zou
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | | | - Ping He
- Department of Biochemistry and Biophysics, Institute for Plant Genomics and Biotechnology, Texas A&M University, Texas, 77840, USA
| | - Hirotada Fukushige
- Department of Agronomy, Agricultural Sciences Center-Noth, University of Kentucky, Lexington, Kentucky, 40546-0091, USA
| | - Liping Yu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Meiyu Shao
- School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Lihuang Zhu
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
| | - David F Hildebrand
- Department of Agronomy, Agricultural Sciences Center-Noth, University of Kentucky, Lexington, Kentucky, 40546-0091, USA
| | - Xiaoyan Tang
- School of Life Sciences, Capital Normal University, Beijing, 100048, China
| | - Jian-Min Zhou
- State Key Laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China
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24
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Kamano S, Kume S, Iida K, Lei KJ, Nakano M, Nakayama Y, Iida H. Transmembrane Topologies of Ca2+-permeable Mechanosensitive Channels MCA1 and MCA2 in Arabidopsis thaliana. J Biol Chem 2015; 290:30901-9. [PMID: 26555262 DOI: 10.1074/jbc.m115.692574] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Indexed: 11/06/2022] Open
Abstract
Sensing mechanical stresses, including touch, stretch, compression, and gravity, is crucial for growth and development in plants. A good mechanosensor candidate is the Ca(2+)-permeable mechanosensitive (MS) channel, the pore of which opens to permeate Ca(2+) in response to mechanical stresses. However, the structure-function relationships of plant MS channels are poorly understood. Arabidopsis MCA1 and MCA2 form a homotetramer and exhibit Ca(2+)-permeable MS channel activity; however, their structures have only been partially elucidated. The transmembrane topologies of these ion channels need to be determined in more detail to elucidate the underlying regulatory mechanisms. We herein determined the topologies of MCA1 and MCA2 using two independent methods, the Suc2C reporter and split-ubiquitin yeast two-hybrid methods, and found that both proteins are single-pass type I integral membrane proteins with extracellular N termini and intracellular C termini. These results imply that an EF hand-like motif, coiled-coil motif, and plac8 motif are all present in the cytoplasm. Thus, the activities of both channels can be regulated by intracellular Ca(2+) and protein interactions.
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Affiliation(s)
- Shumpei Kamano
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
| | - Shinichiro Kume
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
| | - Kazuko Iida
- Laboratory of Biomembrane, Tokyo Metropolitan Institute of Medical Science, 2-1-6 Kamikitazawa, Setagaya, Tokyo 156-8506, Japan
| | - Kai-Jian Lei
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
| | - Masataka Nakano
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
| | - Yoshitaka Nakayama
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
| | - Hidetoshi Iida
- From the Department of Biology, Tokyo Gakugei University, 4-1-1 Nukui kita-machi, Koganei, Tokyo 184-8501, Japan and
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25
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Hamilton ES, Schlegel AM, Haswell ES. United in diversity: mechanosensitive ion channels in plants. ANNUAL REVIEW OF PLANT BIOLOGY 2014; 66:113-37. [PMID: 25494462 PMCID: PMC4470482 DOI: 10.1146/annurev-arplant-043014-114700] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Mechanosensitive (MS) ion channels are a common mechanism for perceiving and responding to mechanical force. This class of mechanoreceptors is capable of transducing membrane tension directly into ion flux. In plant systems, MS ion channels have been proposed to play a wide array of roles, from the perception of touch and gravity to the osmotic homeostasis of intracellular organelles. Three families of plant MS ion channels have been identified: the MscS-like (MSL), Mid1-complementing activity (MCA), and two-pore potassium (TPK) families. Channels from these families vary widely in structure and function, localize to multiple cellular compartments, and conduct chloride, calcium, and/or potassium ions. However, they are still likely to represent only a fraction of the MS ion channel diversity in plant systems.
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Affiliation(s)
- Eric S. Hamilton
- Department of Biology, Washington University in Saint Louis, Saint Louis, Missouri 63130
| | - Angela M. Schlegel
- Department of Biology, Washington University in Saint Louis, Saint Louis, Missouri 63130
| | - Elizabeth S. Haswell
- Department of Biology, Washington University in Saint Louis, Saint Louis, Missouri 63130
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Organellar mechanosensitive channels involved in hypo-osmoregulation in fission yeast. Cell Calcium 2014; 56:467-71. [PMID: 25454595 DOI: 10.1016/j.ceca.2014.10.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Revised: 10/01/2014] [Accepted: 10/04/2014] [Indexed: 01/26/2023]
Abstract
MscS and MscL, bacterial mechanosensitive channels, play crucial roles in the hypo-osmotic shock response. However, only MscS has homologs in eukaryotes. These homologs are called MscS-like proteins or MSL proteins. MSL proteins have changed both structurally and functionally during evolution and are now localized not only to the membrane of the chloroplast, which is thought to be a descendant of an ancient, free-living bacterium, but also the cell membrane and the endoplasmic reticulum (ER) membrane, suggesting that the role of MSL proteins has diverged. In this brief review, we mainly focus on two MSL proteins in the fission yeast Schizosaccharomyces pombe that are localized in the ER membrane and protect cells from hypo-osmotic shock-induced death by regulating intracellular Ca(2+) concentrations. We also discuss Arabidopsis thaliana MSL proteins and other yeast ion channels in terms of osmoregulation in eukaryotes.
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Martinac B, Nomura T, Chi G, Petrov E, Rohde PR, Battle AR, Foo A, Constantine M, Rothnagel R, Carne S, Deplazes E, Cornell B, Cranfield CG, Hankamer B, Landsberg MJ. Bacterial mechanosensitive channels: models for studying mechanosensory transduction. Antioxid Redox Signal 2014; 20:952-69. [PMID: 23834368 DOI: 10.1089/ars.2013.5471] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
SIGNIFICANCE Sensations of touch and hearing are manifestations of mechanical contact and air pressure acting on touch receptors and hair cells of the inner ear, respectively. In bacteria, osmotic pressure exerts a significant mechanical force on their cellular membrane. Bacteria have evolved mechanosensitive (MS) channels to cope with excessive turgor pressure resulting from a hypo-osmotic shock. MS channel opening allows the expulsion of osmolytes and water, thereby restoring normal cellular turgor and preventing cell lysis. RECENT ADVANCES As biological force-sensing systems, MS channels have been identified as the best examples of membrane proteins coupling molecular dynamics to cellular mechanics. The bacterial MS channel of large conductance (MscL) and MS channel of small conductance (MscS) have been subjected to extensive biophysical, biochemical, genetic, and structural analyses. These studies have established MscL and MscS as model systems for mechanosensory transduction. CRITICAL ISSUES In recent years, MS ion channels in mammalian cells have moved into focus of mechanotransduction research, accompanied by an increased awareness of the role they may play in the pathophysiology of diseases, including cardiac hypertrophy, muscular dystrophy, or Xerocytosis. FUTURE DIRECTIONS A recent exciting development includes the molecular identification of Piezo proteins, which function as nonselective cation channels in mechanosensory transduction associated with senses of touch and pain. Since research on Piezo channels is very young, applying lessons learned from studies of bacterial MS channels to establishing the mechanism by which the Piezo channels are mechanically activated remains one of the future challenges toward a better understanding of the role that MS channels play in mechanobiology.
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Affiliation(s)
- Boris Martinac
- 1 Molecular Cardiology and Biophysics Division/Mechanosensory Biophysics Laboratory, Victor Chang Cardiac Research Institute , Darlinghurst, Australia
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Peyronnet R, Tran D, Girault T, Frachisse JM. Mechanosensitive channels: feeling tension in a world under pressure. FRONTIERS IN PLANT SCIENCE 2014; 5:558. [PMID: 25374575 PMCID: PMC4204436 DOI: 10.3389/fpls.2014.00558] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2014] [Accepted: 09/29/2014] [Indexed: 05/02/2023]
Abstract
Plants, like other organisms, are facing multiple mechanical constraints generated both in their tissues and by the surrounding environments. They need to sense and adapt to these forces throughout their lifetimes. To do so, different mechanisms devoted to force transduction have emerged. Here we focus on fascinating proteins: the mechanosensitive (MS) channels. Mechanosensing in plants has been described for centuries but the molecular identification of MS channels occurred only recently. This review is aimed at plant biologists and plant biomechanists who want to be introduced to MS channel identity, how they work and what they might do in planta? In this review, electrophysiological properties, regulations, and functions of well-characterized MS channels belonging to bacteria and animals are compared with those of plants. Common and specific properties are discussed. We deduce which tools and concepts from animal and bacterial fields could be helpful for improving our understanding of plant mechanotransduction. MS channels embedded in their plasma membrane are sandwiched between the cell wall and the cytoskeleton. The consequences of this peculiar situation are analyzed and discussed. We also stress how important it is to probe mechanical forces at cellular and subcellular levels in planta in order to reveal the intimate relationship linking the membrane with MS channel activity. Finally we will propose new tracks to help to reveal their physiological functions at tissue and plant levels.
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Affiliation(s)
- Rémi Peyronnet
- National Heart and Lung Institute, Imperial College LondonLondon, UK
| | - Daniel Tran
- Institut des Sciences du Végétal – Centre National de la Recherche Scientifique, Saclay Plant SciencesGif-sur-Yvette, France
| | - Tiffanie Girault
- Institut des Sciences du Végétal – Centre National de la Recherche Scientifique, Saclay Plant SciencesGif-sur-Yvette, France
| | - Jean-Marie Frachisse
- Institut des Sciences du Végétal – Centre National de la Recherche Scientifique, Saclay Plant SciencesGif-sur-Yvette, France
- *Correspondence: Jean-Marie Frachisse, Institut des Sciences du Végétal – Centre National de la Recherche Scientifique, Saclay Plant Sciences, Bat 22-23A, Avenue de la Terrasse, 91198 Gif-sur-Yvette, France e-mail:
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Monshausen GB, Haswell ES. A force of nature: molecular mechanisms of mechanoperception in plants. JOURNAL OF EXPERIMENTAL BOTANY 2013; 64:4663-80. [PMID: 23913953 PMCID: PMC3817949 DOI: 10.1093/jxb/ert204] [Citation(s) in RCA: 138] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The ability to sense and respond to a wide variety of mechanical stimuli-gravity, touch, osmotic pressure, or the resistance of the cell wall-is a critical feature of every plant cell, whether or not it is specialized for mechanotransduction. Mechanoperceptive events are an essential part of plant life, required for normal growth and development at the cell, tissue, and whole-plant level and for the proper response to an array of biotic and abiotic stresses. One current challenge for plant mechanobiologists is to link these physiological responses to specific mechanoreceptors and signal transduction pathways. Here, we describe recent progress in the identification and characterization of two classes of putative mechanoreceptors, ion channels and receptor-like kinases. We also discuss how the secondary messenger Ca(2+) operates at the centre of many of these mechanical signal transduction pathways.
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Affiliation(s)
| | - Elizabeth S. Haswell
- Department of Biology, Washington University in St Louis, St Louis, MO 63130, USA
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Wilson ME, Maksaev G, Haswell ES. MscS-like mechanosensitive channels in plants and microbes. Biochemistry 2013; 52:5708-22. [PMID: 23947546 DOI: 10.1021/bi400804z] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The challenge of osmotic stress is something all living organisms must face as a result of environmental dynamics. Over the past three decades, innovative research and cooperation across disciplines have irrefutably established that cells utilize mechanically gated ion channels to release osmolytes and prevent cell lysis during hypoosmotic stress. Early electrophysiological analysis of the inner membrane of Escherichia coli identified the presence of three distinct mechanosensitive activities. The subsequent discoveries of the genes responsible for two of these activities, the mechanosensitive channels of large (MscL) and small (MscS) conductance, led to the identification of two diverse families of mechanosensitive channels. The latter of these two families, the MscS family, consists of members from bacteria, archaea, fungi, and plants. Genetic and electrophysiological analysis of these family members has provided insight into how organisms use mechanosensitive channels for osmotic regulation in response to changing environmental and developmental circumstances. Furthermore, determining the crystal structure of E. coli MscS and several homologues in several conformational states has contributed to our understanding of the gating mechanisms of these channels. Here we summarize our current knowledge of MscS homologues from all three domains of life and address their structure, proposed physiological functions, electrophysiological behaviors, and topological diversity.
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Affiliation(s)
- Margaret E Wilson
- Department of Biology, Washington University in St. Louis, Missouri 63130, United States
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Kurusu T, Kuchitsu K, Nakano M, Nakayama Y, Iida H. Plant mechanosensing and Ca2+ transport. TRENDS IN PLANT SCIENCE 2013; 18:227-33. [PMID: 23291244 DOI: 10.1016/j.tplants.2012.12.002] [Citation(s) in RCA: 92] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Revised: 11/26/2012] [Accepted: 12/04/2012] [Indexed: 05/18/2023]
Abstract
Mechanical stimuli generate Ca(2+) signals and influence growth and development in plants. Recently, candidates for Ca(2+)-permeable mechanosensitive (MS) channels have been identified. These channels are thought to be responsible for sensing osmotic shock, touch, and gravity. One candidate is the MscS-like (MSL) protein family, a homolog of the typical bacterial MS channels. Some of the MSL proteins are localized to plastids to maintain their shape and size. Another candidate is the mid1-complementing activity (MCA) protein family, which is structurally unique to the plant kingdom. MCA proteins are localized in the plasma membrane and are suggested to be involved in mechanosensing and to be functionally related to reactive oxygen species (ROS) signaling. Here, we review their structural features and role in planta.
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Affiliation(s)
- Takamitsu Kurusu
- Department of Applied Biological Science, Tokyo University of Science, 2641 Yamazaki, Noda, Chiba 278-8510, Japan
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Jensen GS, Haswell ES. Functional analysis of conserved motifs in the mechanosensitive channel homolog MscS-Like2 from Arabidopsis thaliana. PLoS One 2012; 7:e40336. [PMID: 22768278 PMCID: PMC3386975 DOI: 10.1371/journal.pone.0040336] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 06/06/2012] [Indexed: 11/30/2022] Open
Abstract
The Mechanosensitive channel of Small conductance (MscS) of Escherichia coli has become an excellent model system for the structural, biophysical, and functional study of mechanosensitive ion channels. MscS, a complex channel with multiple states, contributes to protection against lysis upon osmotic downshock. MscS homologs are widely and abundantly dispersed among the bacterial and plant lineages, but are not found in animals. Investigation into the eukaryotic branch of the MscS family is in the beginning stages, and it remains unclear how much MscS homologs from eukaryotes resemble E. coli MscS with respect to structure, function, and regulation. Here we test the effect of mutating three conserved motifs on the function of MscS-Like (MSL)2, a MscS homolog localized to the plastids of Arabidopsis thaliana. We show that 1) a motif at the top of the cytoplasmic domain, referred to here as the PN(X)9N motif, is essential for MSL2 function and for its proper intraplastidic localization; 2) substituting polar residues for two large hydrophobic residues located in the predicted pore-lining transmembrane helix of MSL2 produces a likely gain-of-function allele, as previously shown for MscS; and 3) mis-expression of this allele causes severe defects in leaf growth, loss of chloroplast integrity, and abnormal starch accumulation. Thus, two of the three conserved motifs we analyzed are critical for MSL2 function, consistent with the conservation of structure and function between MscS family members in bacteria and plants. These results underscore the importance of plastidic mechanosensitive channels in the maintenance of normal plastid and leaf morphology.
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Affiliation(s)
- Gregory S. Jensen
- Department of Biology, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
| | - Elizabeth S. Haswell
- Department of Biology, Washington University in Saint Louis, Saint Louis, Missouri, United States of America
- * E-mail:
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The MscS and MscL families of mechanosensitive channels act as microbial emergency release valves. J Bacteriol 2012; 194:4802-9. [PMID: 22685280 DOI: 10.1128/jb.00576-12] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Single-celled organisms must survive exposure to environmental extremes. Perhaps one of the most variable and potentially life-threatening changes that can occur is that of a rapid and acute decrease in external osmolarity. This easily translates into several atmospheres of additional pressure that can build up within the cell. Without a protective mechanism against such pressures, the cell will lyse. Hence, most microbes appear to possess members of one or both families of bacterial mechanosensitive channels, MscS and MscL, which can act as biological emergency release valves that allow cytoplasmic solutes to be jettisoned rapidly from the cell. While this is undoubtedly a function of these proteins, the discovery of the presence of MscS homologues in plant organelles and MscL in fungus and mycoplasma genomes may complicate this simplistic interpretation of the physiology underlying these proteins. Here we compare and contrast these two mechanosensitive channel families, discuss their potential physiological roles, and review some of the most relevant data that underlie the current models for their structure and function.
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Veley KM, Haswell ES. Plastids and pathogens: mechanosensitive channels and survival in a hypoosmotic world. PLANT SIGNALING & BEHAVIOR 2012; 7:668-71. [PMID: 22580705 PMCID: PMC3442863 DOI: 10.4161/psb.19991] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
In bacteria, MscS-type mechanosensitive channels serve to protect cells from lysis as they swell during extreme osmotic stress. We recently showed that two MscS homologs from Arabidopsis thaliana serve a similar purpose in the epidermal plastids of the leaf, indicating that the plant cell cytoplasm can present a dynamic osmotic challenge to the plastid. MscS homologs are predicted to be targeted to both plastids and mitochondrial envelopes and have been found in the genomes of intracellular pathogens. Here we discuss the implications of these observations, and propose that MS channels provide an essential mechanism for osmotic adaptation to both intracellular and the extracellular environments.
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Wilson ME, Jensen GS, Haswell ES. Two mechanosensitive channel homologs influence division ring placement in Arabidopsis chloroplasts. THE PLANT CELL 2011; 23:2939-49. [PMID: 21810996 PMCID: PMC3180802 DOI: 10.1105/tpc.111.088112] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2011] [Revised: 07/14/2011] [Accepted: 07/18/2011] [Indexed: 05/18/2023]
Abstract
Chloroplasts must divide repeatedly to maintain their population during plant growth and development. A number of proteins required for chloroplast division have been identified, and the functional relationships between them are beginning to be elucidated. In both chloroplasts and bacteria, the future site of division is specified by placement of the Filamentous temperature sensitive Z (FtsZ) ring, and the Min system serves to restrict FtsZ ring formation to mid-chloroplast or mid-cell. How the Min system is regulated in response to environmental and developmental factors is largely unstudied. Here, we investigated the role in chloroplast division played by two Arabidopsis thaliana homologs of the bacterial mechanosensitive (MS) channel MscS: MscS-Like 2 (MSL2) and MSL3. Immunofluorescence microscopy and live imaging approaches demonstrated that msl2 msl3 double mutants have enlarged chloroplasts containing multiple FtsZ rings. Genetic analyses indicate that MSL2, MSL3, and components of the Min system function in the same pathway to regulate chloroplast size and FtsZ ring formation. In addition, an Escherichia coli strain lacking MS channels also showed aberrant FtsZ ring assembly. These results establish MS channels as components of the chloroplast division machinery and suggest that their role is evolutionarily conserved.
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Abstract
Mechanosensitive ion channels are gated directly by physical stimuli and transduce these stimuli into electrical signals. Several criteria must apply for a channel to be considered mechanically gated. Mechanosensitive channels from bacterial systems have met these criteria, but few eukaryotic channels have been confirmed by the same standards. Recent work has suggested or confirmed that diverse types of channels, including TRP channels, K(2P) channels, MscS-like proteins, and DEG/ENaC channels, are mechanically gated. Several studies point to the importance of the plasma membrane for channel gating, but intracellular and/or extracellular structures may also be required.
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Affiliation(s)
- Jóhanna Arnadóttir
- Department of Biological Sciences, Columbia University, New York, New York 10027, USA.
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37
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Niklas KJ. Functional adaptation and phenotypic plasticity at the cellular and whole plant level. J Biosci 2009; 34:613-20. [DOI: 10.1007/s12038-009-0079-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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38
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Porter BW, Zhu YJ, Webb DT, Christopher DA. Novel thigmomorphogenetic responses in Carica papaya: touch decreases anthocyanin levels and stimulates petiole cork outgrowths. ANNALS OF BOTANY 2009; 103:847-58. [PMID: 19182220 PMCID: PMC2707888 DOI: 10.1093/aob/mcp009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2008] [Revised: 11/05/2008] [Accepted: 12/04/2008] [Indexed: 05/27/2023]
Abstract
BACKGROUND AND AIMS Because of its rapid growth rate, relative ease of transformation, sequenced genome and low gene number relative to Arabidopsis, the tropical fruit tree, Carica papaya, can serve as a complementary genetic model for complex traits. Here, new phenotypes and touch-regulated gene homologues have been identified that can be used to advance the understanding of thigmomorphogenesis, a multigenic response involving mechanoreception and morphological change. METHODS Morphological alterations were quantified, and microscopy of tissue was conducted. Assays for hypocotyl anthocyanins, lignin and chlorophyll were performed, and predicted genes from C. papaya were compared with Arabidopsis touch-inducible (TCH) and Mechanosensitive channel of Small conductance-like genes (MscS-like or MSL). In addition, the expression of two papaya TCH1 homologues was characterized. KEY RESULTS On the abaxial side of petioles, treated plants were found to have novel, hypertrophic outgrowths associated with periderm and suberin. Touched plants also had higher lignin, dramatically less hypocotyl anthocyanins and chlorophyll, increased hypocotyl diameter, and decreased leaf width, stem length and root fresh weight. Papaya was found to have fewer MSL genes than Arabidopsis, and four touch-regulated genes in Arabidopsis had no counterparts in papaya. Water-spray treatment was found to enhance the expression of two papaya TCH1 homologues whereas induction following touch was only slightly correlated. CONCLUSIONS The novel petiole outgrowths caused by non-wounding, mechanical perturbation may be the result of hardening mechanisms, including added lignin, providing resistance against petiole movement. Inhibition of anthocyanin accumulation following touch, a new phenotypic association, may be caused by diversion of p-coumaroyl CoA away from chalcone synthase for lignin synthesis. The absence of MSL and touch-gene homologues indicates that papaya may have a smaller set of touch-regulated genes. The genes and novel touch-regulated phenotypes identified here will contribute to a more comprehensive view of thigmomorphogenesis in plants.
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Affiliation(s)
- Brad W Porter
- Department of Molecular Biosciences and Bioengineering, University of Hawai'i at Mānoa, 1955 East-West Rd, Agricultural Sciences Room 218, Honolulu, HI 96822, USA.
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White PJ, Broadley MR. Biofortification of crops with seven mineral elements often lacking in human diets--iron, zinc, copper, calcium, magnesium, selenium and iodine. THE NEW PHYTOLOGIST 2009; 182:49-84. [PMID: 19192191 DOI: 10.1111/j.1469-8137.2008.02738.x] [Citation(s) in RCA: 747] [Impact Index Per Article: 49.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The diets of over two-thirds of the world's population lack one or more essential mineral elements. This can be remedied through dietary diversification, mineral supplementation, food fortification, or increasing the concentrations and/or bioavailability of mineral elements in produce (biofortification). This article reviews aspects of soil science, plant physiology and genetics underpinning crop biofortification strategies, as well as agronomic and genetic approaches currently taken to biofortify food crops with the mineral elements most commonly lacking in human diets: iron (Fe), zinc (Zn), copper (Cu), calcium (Ca), magnesium (Mg), iodine (I) and selenium (Se). Two complementary approaches have been successfully adopted to increase the concentrations of bioavailable mineral elements in food crops. First, agronomic approaches optimizing the application of mineral fertilizers and/or improving the solubilization and mobilization of mineral elements in the soil have been implemented. Secondly, crops have been developed with: increased abilities to acquire mineral elements and accumulate them in edible tissues; increased concentrations of 'promoter' substances, such as ascorbate, beta-carotene and cysteine-rich polypeptides which stimulate the absorption of essential mineral elements by the gut; and reduced concentrations of 'antinutrients', such as oxalate, polyphenolics or phytate, which interfere with their absorption. These approaches are addressing mineral malnutrition in humans globally.
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Affiliation(s)
- Philip J White
- The Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, UK
| | - Martin R Broadley
- Plant and Crop Sciences Division, School of Biosciences, University of Nottingham, Sutton Bonington Campus, Loughborough LE12 5RD, UK
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Shepherd VA, Beilby MJ, Al Khazaaly SAS, Shimmen T. Mechano-perception in Chara cells: the influence of salinity and calcium on touch-activated receptor potentials, action potentials and ion transport. PLANT, CELL & ENVIRONMENT 2008; 31:1575-91. [PMID: 18684243 DOI: 10.1111/j.1365-3040.2008.01866.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
This paper investigates the impact of increased salinity on touch-induced receptor and action potentials of Chara internodal cells. We resolved underlying changes in ion transport by current/voltage analysis. In a saline medium with a low Ca(2+) ion concentration [(Ca(2+))(ext)], the cell background conductance significantly increased and proton pump currents declined to negligible levels, depolarizing the membrane potential difference (PD) to the excitation threshold [action potential (AP)(threshold)]. The onset of spontaneous repetitive action potentials further depolarized the PD, activating K(+) outward rectifying (KOR) channels. K(+) efflux was then sustained and irrevocable, and cells were desensitized to touch. However, when [Ca(2+)](ext) was high, the background conductance increased to a lesser extent and proton pump currents were stimulated, establishing a PD narrowly negative to AP(threshold). Cells did not spontaneously fire, but became hypersensitive to touch. Even slight touch stimulus induced an action potential and further repetitive firing. The duration of each excitation was extended when [Ca(2+)](ext) was low. Cell viability was prolonged in the absence of touch stimulus. Chara cells eventually depolarize and die in the saline media, but touch-stimulated and spontaneous excitation accelerates the process in a Ca(2+)-dependent manner. Our results have broad implications for understanding the interactions between mechano-perception and salinity stress in plants.
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Affiliation(s)
- Virginia A Shepherd
- Department of Biophysics, School of Physics, The University of New South Wales, Sydney, New South Wales 2052, Australia.
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