1
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Chen Q, Wang Z, Wei H, Wang J, Zhou W, Zhou P, Li D. Environmental concentrations of anionic surfactants in lake surface microlayers enhance the toxicity of Microcystis blooms: Insight from photosynthesis, interspecies competition, and MC production. WATER RESEARCH 2023; 244:120430. [PMID: 37678037 DOI: 10.1016/j.watres.2023.120430] [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: 06/06/2023] [Revised: 07/25/2023] [Accepted: 07/27/2023] [Indexed: 09/09/2023]
Abstract
Anionic surfactants represented by linear alkylbenzene sulfonate (LAS) exhibit vertical heterogeneity of concentrations in aquatic environments owing to their amphiphilic structure. Field investigations showed that the concentration of anionic surfactants (mainly LAS) in the water surface microlayer (SML) of Lake Taihu reached 580 μg/L, higher than that in the lower layer. Floating Microcystis blooms overlap in space with the high concentration of anionic surfactants in SML. However, few studies have focused on the effects of anionic surfactants (e.g., LAS) on the interspecies competition between toxic and nontoxic Microcystis. In this study, coculture and monoculture experiments were conducted with both toxic and nontoxic Microcystis species to explore how the environmental concentration of LAS regulates the dominance of toxic Microcystis and toxicity from the perspective of photosynthesis, species dominance, and MC production. The results showed that LAS concentrations above 0.267 or 0.431 mg/L (depending on light conditions) selectively promoted the photosynthetic competitive advantage of toxic Microcystis, leading to its higher population proportion in the community. Additionally, LAS concentrations above 0.5 mg/L induced the synthesis and release of microcystins (MCs). The results of chlorophyll fluorescence analysis, electron microscopy and transcriptome sequencing suggested that compared with nontoxic Microcystis, toxic Microcystis can better resist LAS stress by dissipating excess light, maintaining an intact membrane structure and maintaining cellular homeostasis. Transcriptome sequencing revealed that the photosynthetic damage of nontoxic Microcystis might be attributed to the impacts of LAS on the absorption and assimilation of nitrogen, which finally resulted in the degradation of phycobilisomes. This study can provide novel insight for establishing standards and safety management of wastewater discharge.
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Affiliation(s)
- Qinyi Chen
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Zhicong Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China.
| | - Hui Wei
- Yulin Municipal Ecology and Environment Emergency and Technical Service Center, Yulin 537000, P.R. China
| | - Jinglong Wang
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Weicheng Zhou
- School of Chemistry and Environmental Science, Xiangnan University, Chenzhou 423000, P.R. China
| | - Panpan Zhou
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China; University of Chinese Academy of Sciences, Beijing 100049, P.R. China
| | - Dunhai Li
- Key Laboratory of Algal Biology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, P.R. China
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2
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Ozu M, Galizia L, Alvear-Arias JJ, Fernández M, Caviglia A, Zimmermann R, Guastaferri F, Espinoza-Muñoz N, Sutka M, Sigaut L, Pietrasanta LI, González C, Amodeo G, Garate JA. Mechanosensitive aquaporins. Biophys Rev 2023; 15:497-513. [PMID: 37681084 PMCID: PMC10480384 DOI: 10.1007/s12551-023-01098-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Accepted: 07/04/2023] [Indexed: 09/09/2023] Open
Abstract
Cellular systems must deal with mechanical forces to satisfy their physiological functions. In this context, proteins with mechanosensitive properties play a crucial role in sensing and responding to environmental changes. The discovery of aquaporins (AQPs) marked a significant breakthrough in the study of water transport. Their transport capacity and regulation features make them key players in cellular processes. To date, few AQPs have been reported to be mechanosensitive. Like mechanosensitive ion channels, AQPs respond to tension changes in the same range. However, unlike ion channels, the aquaporin's transport rate decreases as tension increases, and the molecular features of the mechanism are unknown. Nevertheless, some clues from mechanosensitive ion channels shed light on the AQP-membrane interaction. The GxxxG motif may play a critical role in the water permeation process associated with structural features in AQPs. Consequently, a possible gating mechanism triggered by membrane tension changes would involve a conformational change in the cytoplasmic extreme of the single file region of the water pathway, where glycine and histidine residues from loop B play a key role. In view of their transport capacity and their involvement in relevant processes related to mechanical forces, mechanosensitive AQPs are a fundamental piece of the puzzle for understanding cellular responses.
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Affiliation(s)
- Marcelo Ozu
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Luciano Galizia
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Juan José Alvear-Arias
- Interdisciplinary Center of Neurosciences of Valparaiso, University of Valparaiso, CINV, 2360102 Valparaíso, Chile
- Millennium Nucleus in NanoBioPhysics, Santiago, Chile
| | - Miguel Fernández
- Interdisciplinary Center of Neurosciences of Valparaiso, University of Valparaiso, CINV, 2360102 Valparaíso, Chile
- Millennium Nucleus in NanoBioPhysics, Santiago, Chile
| | - Agustín Caviglia
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Rosario Zimmermann
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Florencia Guastaferri
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
- Present Address: Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET-UNR), Rosario, Argentina
| | - Nicolás Espinoza-Muñoz
- Interdisciplinary Center of Neurosciences of Valparaiso, University of Valparaiso, CINV, 2360102 Valparaíso, Chile
- Millennium Nucleus in NanoBioPhysics, Santiago, Chile
| | - Moira Sutka
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Lorena Sigaut
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Buenos Aires, Argentina
- Instituto de Física de Buenos Aires (IFIBA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Lía Isabel Pietrasanta
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Física, Buenos Aires, Argentina
- Instituto de Física de Buenos Aires (IFIBA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Carlos González
- Millennium Nucleus in NanoBioPhysics, Santiago, Chile
- Department of Physiology and Biophysics, Miller School of Medicine, University of Miami, Miami, FL 33136 USA
- Present Address: Molecular Bioscience Department, University of Texas, Austin, TX 78712 USA
| | - Gabriela Amodeo
- Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Biodiversidad y Biología Experimental, Buenos Aires, Argentina
- Instituto de Biodiversidad y Biología Experimental y Aplicada (IBBEA), Universidad de Buenos Aires y Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - José Antonio Garate
- Interdisciplinary Center of Neurosciences of Valparaiso, University of Valparaiso, CINV, 2360102 Valparaíso, Chile
- Millennium Nucleus in NanoBioPhysics, Santiago, Chile
- Facultad de Ingeniería, Arquitectura y Diseño, Universidad San Sebastián, Bellavista, Santiago, Chile
- Centro Científico y Tecnológico de Excelencia Ciencia y Vida, Universidad San Sebastián, 7750000 Santiago, Chile
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3
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Greenlee JD, Liu K, Lopez-Cavestany M, King MR. Piezo1 Mechano-Activation Is Augmented by Resveratrol and Differs between Colorectal Cancer Cells of Primary and Metastatic Origin. Molecules 2022; 27:5430. [PMID: 36080197 PMCID: PMC9458129 DOI: 10.3390/molecules27175430] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/09/2022] [Accepted: 08/20/2022] [Indexed: 11/24/2022] Open
Abstract
Cancer cells must survive aberrant fluid shear stress (FSS) in the circulation to metastasize. Herein, we investigate the role that FSS has on colorectal cancer cell apoptosis, proliferation, membrane damage, calcium influx, and therapeutic sensitization. We tested this using SW480 (primary tumor) and SW620 cells (lymph node metastasis) derived from the same patient. The cells were exposed to either shear pulses, modeling millisecond intervals of high FSS seen in regions of turbulent flow, or sustained shear to model average magnitudes experienced by circulating tumor cells. SW480 cells were significantly more sensitive to FSS-induced death than their metastatic counterparts. Shear pulses caused significant cell membrane damage, while constant shear decreased cell proliferation and increased the expression of CD133. To investigate the role of mechanosensitive ion channels, we treated cells with the Piezo1 agonist Yoda1, which increased intracellular calcium. Pretreatment with resveratrol further increased the calcium influx via the lipid-raft colocalization of Piezo1. However, minimal changes in apoptosis were observed due to calcium saturation, as predicted via a computational model of apoptosis. Furthermore, SW480 cells had increased levels of Piezo1, calcium influx, and TRAIL-mediated apoptosis compared to SW620 cells, highlighting differences in the mechano-activation of metastatic cells, which may be a necessary element for successful dissemination in vivo.
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Affiliation(s)
| | | | | | - Michael R. King
- Department of Biomedical Engineering, Vanderbilt University, PMB 351631, 2301 Vanderbilt Place, Nashville, TN 37235-1631, USA
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4
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Nishida T, Kubota S. Roles of CCN2 as a mechano-sensing regulator of chondrocyte differentiation. JAPANESE DENTAL SCIENCE REVIEW 2020; 56:119-126. [PMID: 33088364 PMCID: PMC7560579 DOI: 10.1016/j.jdsr.2020.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Revised: 07/07/2020] [Accepted: 07/20/2020] [Indexed: 12/17/2022] Open
Abstract
Cellular communication network factor 2 (CCN2) is a cysteine-rich secreted matricellular protein that regulates various cellular functions including cell differentiation. CCN2 is highly expressed under several types of mechanical stress, such as stretch, compression, and shear stress, in mesenchymal cells including chondrocytes, osteoblasts, and fibroblasts. In particular, CCN2 not only promotes cell proliferation and differentiation of various cells but also regulates the stability of mRNA of TRPV4, a mechanosensitive ion channel in chondrocytes. Of note, CCN2 behaves like a biomarker to sense suitable mechanical stress, because CCN2 expression is down-regulated when chondrocytes are subjected to excessive mechanical stress. These findings suggest that CCN2 is a mechano-sensing regulator. CCN2 expression is regulated by the activation of various mechano-sensing signaling pathways, e.g., mechanosensitive ion channels, integrin-focal adhesion-actin dynamics, Rho GTPase family members, Hippo-YAP signaling, and G protein-coupled receptors. This review summarizes the characterization of mechanoreceptors involved in CCN2 gene regulation and discusses the role of CCN2 as a mechano-sensing regulator of mesenchymal cell differentiation, with particular focus on chondrocytes.
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Affiliation(s)
- Takashi Nishida
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8525, Japan.,Advanced Research Center for Oral and Craniofacial Sciences, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8525, Japan
| | - Satoshi Kubota
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama 700-8525, Japan
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5
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Azulay H, Lutaty A, Qvit N. Approach for comparing protein structures and origami models. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2020; 1862:183132. [PMID: 31738904 DOI: 10.1016/j.bbamem.2019.183132] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 10/05/2019] [Accepted: 10/28/2019] [Indexed: 11/20/2022]
Abstract
The research fields of proteins and origami have intersected in the study of folding and de-novo design of proteins. However, there is limited knowledge on the analogy between protein structures and origami models. We propose a general approach for comparing protein structures with origami models, and present a test case, comparing transmembrane β-barrel and α-helical barrel with the Yoshimura and Kresling origami models. While both shapes and structures may look similar, we demonstrated that the β-barrel and the α-helical barrel are in agreement only with the shape and structural characteristics of the Kresling model. Through the analogy, it is explained how the structural characteristic can help the β-barrel and α-helical barrel to adjust length and diameter in response to changes in the membrane structure. However, such conformations only apply to the α-helical barrel, and the β-barrel, in spite of resembles to the Kresling model, remains stiff due to hydrogen bonds between the β-strands. Thus, our analysis suggests that there are similar patterns between protein structures and origami models and that the proposed approach may provide important insight on the role that the structure of a protein fulfils, and on the preferred structural design of novel proteins with unique characteristics.
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Affiliation(s)
| | | | - Nir Qvit
- The Azrieli Faculty of Medicine in the Galilee, Bar-Ilan University, Henrietta Szold St. 8, POB 1589, Safed, Israel.
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6
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Aldebs AI, Zohora FT, Nosoudi N, Singh SP, Ramirez‐Vick JE. Effect of Pulsed Electromagnetic Fields on Human Mesenchymal Stem Cells Using 3D Magnetic Scaffolds. Bioelectromagnetics 2020; 41:175-187. [PMID: 31944364 PMCID: PMC9290550 DOI: 10.1002/bem.22248] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Accepted: 01/01/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Alyaa I. Aldebs
- Department of Biomedical, Industrial & Human Factors EngineeringWright State UniversityDayton Ohio
| | - Fatema T. Zohora
- Department of Biomedical, Industrial & Human Factors EngineeringWright State UniversityDayton Ohio
| | - Nasim Nosoudi
- Biomedical Engineering ProgramMarshall UniversityHuntington West Virginia
| | | | - Jaime E. Ramirez‐Vick
- Department of Biomedical, Industrial & Human Factors EngineeringWright State UniversityDayton Ohio
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7
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Amemiya S, Toyoda H, Kimura M, Saito H, Kobayashi H, Ihara K, Kamagata K, Kawabata R, Kato S, Nakashimada Y, Furuta T, Hamamoto S, Uozumi N. The mechanosensitive channel YbdG from Escherichia coli has a role in adaptation to osmotic up-shock. J Biol Chem 2019; 294:12281-12292. [PMID: 31256002 DOI: 10.1074/jbc.ra118.007340] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 06/20/2019] [Indexed: 01/24/2023] Open
Abstract
Mechanosensitive channels play an important role in the adaptation of cells to hypo-osmotic shock. Among members of this channel family in Escherichia coli, the exact function and physiological role of the mechanosensitive channel homolog YbdG remain unclear. Characterization of YbdG's physiological role has been hampered by its lack of measurable transport activity. Using a nitrosoguanidine mutagenesis-aided screen in combination with next-generation sequencing, here we isolated a mutant with a point mutation in ybdG This mutation (resulting in a I167T change) conferred sensitivity to high osmotic stress, and the mutant cells differed from WT cells in morphology during hyperosmotic stress at alkaline pH. Interestingly, unlike the cells containing the I167T variant, a null-ybdG mutant did not exhibit this sensitivity and phenotype. Although I167T was located near the putative ion-conducting pore in a transmembrane region of YbdG, no change in ion channel activities of YbdG-I167T was detected. Of note, introduction of the WT C-terminal cytosolic region of YbdG into the I167T variant complemented the osmo-sensitive phenotype. Co-precipitation of proteins interacting with the C-terminal YbdG region led to the isolation of HldD and FbaA, whose overexpression in cells containing the YbdG-I167T variant partially rescued the osmo-sensitive phenotype. This study indicates that YbdG functions as a component of a mechanosensing system that transmits signals triggered by external osmotic changes to intracellular factors. The cellular role of YbdG uncovered here goes beyond its predicted function as an ion or solute transport protein.
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Affiliation(s)
- Shun Amemiya
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 6-6-07, Sendai 980-8579, Japan
| | - Hayato Toyoda
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 6-6-07, Sendai 980-8579, Japan
| | - Mami Kimura
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 6-6-07, Sendai 980-8579, Japan
| | - Hiromi Saito
- Department of Biochemistry, Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Hiroshi Kobayashi
- Department of Biochemistry, Graduate School of Pharmaceutical Science, Chiba University, Chiba 260-8675, Japan
| | - Kunio Ihara
- Center for Gene Research, Nagoya University, Nagoya 464-8602, Japan
| | - Kiyoto Kamagata
- Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, Katahira 2-1-1, Sendai 980-8577, Japan
| | - Ryuji Kawabata
- School of Engineering, Hiroshima University, Higashi-Hiroshima 739-8527, Japan
| | - Setsu Kato
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima 739-8530, Japan
| | - Yutaka Nakashimada
- Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Higashi-Hiroshima 739-8530, Japan
| | - Tadaomi Furuta
- School of Life Science and Technology, Tokyo Institute of Technology, B-62 4259 Nagatsuta-cho, Midori-ku, Yokohama 226-8501, Japan
| | - Shin Hamamoto
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 6-6-07, Sendai 980-8579, Japan
| | - Nobuyuki Uozumi
- Department of Biomolecular Engineering, Graduate School of Engineering, Tohoku University, Aobayama 6-6-07, Sendai 980-8579, Japan.
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8
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Abstract
Mechanosensitive (MS) channels protect bacteria against hypo-osmotic shock and fulfil additional functions. Hypo-osmotic shock leads to high turgor pressure that can cause cell rupture and death. MS channels open under these conditions and release unspecifically solutes and consequently the turgor pressure. They can recognise the raised pressure via the increased tension in the cell membrane. Currently, a better understanding how MS channels can sense tension on molecular level is developing because the interaction of the lipid bilayer with the channel is being investigated in detail. The MS channel of large conductance (MscL) and of small conductance (MscS) have been distinguished and studied in molecular detail. In addition, larger channels were found that contain a homologous region corresponding to MscS so that MscS represents a family of channels. Often several members of this family are present in a species. The importance of this family is underlined by the fact that members can be found not only in bacteria but also in higher organisms. While MscL and MscS have been studied for years in particular by electrophysiology, mutagenesis, molecular dynamics, X-ray crystallography and other biophysical techniques, only recently more details are emerging about other members of the MscS-family.
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9
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Zhang L, Zhang Z, Jasa J, Li D, Cleveland RO, Negahban M, Jérusalem A. Molecular dynamics simulations of heterogeneous cell membranes in response to uniaxial membrane stretches at high loading rates. Sci Rep 2017; 7:8316. [PMID: 28814791 PMCID: PMC5559491 DOI: 10.1038/s41598-017-06827-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 06/19/2017] [Indexed: 01/02/2023] Open
Abstract
The chemobiomechanical signatures of diseased cells are often distinctively different from that of healthy cells. This mainly arises from cellular structural/compositional alterations induced by disease development or therapeutic molecules. Therapeutic shock waves have the potential to mechanically destroy diseased cells and/or increase cell membrane permeability for drug delivery. However, the biomolecular mechanisms by which shock waves interact with diseased and healthy cellular components remain largely unknown. By integrating atomistic simulations with a novel multiscale numerical framework, this work provides new biomolecular mechanistic perspectives through which many mechanosensitive cellular processes could be quantitatively characterised. Here we examine the biomechanical responses of the chosen representative membrane complexes under rapid mechanical loadings pertinent to therapeutic shock wave conditions. We find that their rupture characteristics do not exhibit significant sensitivity to the applied strain rates. Furthermore, we show that the embedded rigid inclusions markedly facilitate stretch-induced membrane disruptions while mechanically stiffening the associated complexes under the applied membrane stretches. Our results suggest that the presence of rigid molecules in cellular membranes could serve as “mechanical catalysts” to promote the mechanical destructions of the associated complexes, which, in concert with other biochemical/medical considerations, should provide beneficial information for future biomechanical-mediated therapeutics.
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Affiliation(s)
- Lili Zhang
- University of Oxford, Department of Engineering Science, Oxford, OX1 3PJ, UK.
| | - Zesheng Zhang
- University of Nebraska-Lincoln, Department of Mechanical and Materials Engineering, Lincoln, NE 68588, USA
| | - John Jasa
- University of Nebraska-Lincoln, Department of Mechanical and Materials Engineering, Lincoln, NE 68588, USA
| | - Dongli Li
- University of Oxford, Institute of Biomedical Engineering, Oxford, OX3 7DQ, UK
| | - Robin O Cleveland
- University of Oxford, Institute of Biomedical Engineering, Oxford, OX3 7DQ, UK
| | - Mehrdad Negahban
- University of Nebraska-Lincoln, Department of Mechanical and Materials Engineering, Lincoln, NE 68588, USA
| | - Antoine Jérusalem
- University of Oxford, Department of Engineering Science, Oxford, OX1 3PJ, UK.
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10
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Suki B, Parameswaran H, Imsirovic J, Bartolák-Suki E. Regulatory Roles of Fluctuation-Driven Mechanotransduction in Cell Function. Physiology (Bethesda) 2017; 31:346-58. [PMID: 27511461 DOI: 10.1152/physiol.00051.2015] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Cells in the body are exposed to irregular mechanical stimuli. Here, we review the so-called fluctuation-driven mechanotransduction in which stresses stretching cells vary on a cycle-by-cycle basis. We argue that such mechanotransduction is an emergent network phenomenon and offer several potential mechanisms of how it regulates cell function. Several examples from the vasculature, the lung, and tissue engineering are discussed. We conclude with a list of important open questions.
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Affiliation(s)
- Béla Suki
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
| | | | - Jasmin Imsirovic
- Department of Biomedical Engineering, Boston University, Boston, Massachusetts
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11
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Dimitrova A, Walko M, Hashemi Shabestari M, Kumar P, Huber M, Kocer A. In situ, Reversible Gating of a Mechanosensitive Ion Channel through Protein-Lipid Interactions. Front Physiol 2016; 7:409. [PMID: 27708587 PMCID: PMC5030285 DOI: 10.3389/fphys.2016.00409] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 08/30/2016] [Indexed: 12/14/2022] Open
Abstract
Understanding the functioning of ion channels, as well as utilizing their properties for biochemical applications requires control over channel activity. Herein we report a reversible control over the functioning of a mechanosensitive ion channel by interfering with its interaction with the lipid bilayer. The mechanosensitive channel of large conductance from Escherichia coli is reconstituted into liposomes and activated to its different sub-open states by titrating lysophosphatidylcholine (LPC) into the lipid bilayer. Activated channels are closed back by the removal of LPC out of the membrane by bovine serum albumin (BSA). Electron paramagnetic resonance spectra showed the LPC-dose-dependent gradual opening of the channel pore in the form of incrementally increasing spin label mobility and decreasing spin-spin interaction. A method to reversibly open and close mechanosensitive channels to distinct sub-open conformations during their journey from the closed to the fully open state enables detailed structural studies to follow the conformational changes during channel functioning. The ability of BSA to revert the action of LPC opens new perspectives for the functional studies of other membrane proteins that are known to be activated by LPC.
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Affiliation(s)
- Anna Dimitrova
- Department of Biochemistry, University of GroningenGroningen, Netherlands
| | - Martin Walko
- Department of Biochemistry, University of GroningenGroningen, Netherlands
| | | | - Pravin Kumar
- Huygens-Kamerlingh Onnes Laboratory, Department of Physics, Leiden UniversityLeiden, Netherlands
| | - Martina Huber
- Huygens-Kamerlingh Onnes Laboratory, Department of Physics, Leiden UniversityLeiden, Netherlands
| | - Armagan Kocer
- Neuroscience Department, University of Groningen, University Medical Center GroningenGroningen, Netherlands
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12
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Ishikawa T, Tanaka T, Imai Y, Omori T, Matsunaga D. Deformation of a micro-torque swimmer. Proc Math Phys Eng Sci 2016; 472:20150604. [PMID: 26997893 PMCID: PMC4786038 DOI: 10.1098/rspa.2015.0604] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2015] [Accepted: 12/15/2015] [Indexed: 11/25/2022] Open
Abstract
The membrane tension of some kinds of ciliates has been suggested to regulate upward and downward swimming velocities under gravity. Despite its biological importance, deformation and membrane tension of a ciliate have not been clarified fully. In this study, we numerically investigated the deformation of a ciliate swimming freely in a fluid otherwise at rest. The cell body was modelled as a capsule with a hyperelastic membrane enclosing a Newtonian fluid. Thrust forces due to the ciliary beat were modelled as torques distributed above the cell body. The effects of membrane elasticity, the aspect ratio of the cell's reference shape, and the density difference between the cell and the surrounding fluid were investigated. The results showed that the cell deformed like a heart shape, when the capillary number was sufficiently large. Under the influence of gravity, the membrane tension at the anterior end decreased in the upward swimming while it increased in the downward swimming. Moreover, gravity-induced deformation caused the cells to move gravitationally downwards or upwards, which resulted in a positive or negative geotaxis-like behaviour with a physical origin. These results are important in understanding the physiology of a ciliate's biological responses to mechanical stimuli.
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Affiliation(s)
- Takuji Ishikawa
- Department of Bioengineering and Robotics, Tohoku University, 6-6-01, Aoba, Sendai 980-8579, Japan
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13
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Svetina S. Curvature-dependent protein–lipid bilayer interaction and cell mechanosensitivity. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2015; 44:513-9. [DOI: 10.1007/s00249-015-1046-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2015] [Revised: 05/13/2015] [Accepted: 05/14/2015] [Indexed: 05/28/2023]
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14
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Shen B, Wong CO, Lau OC, Woo T, Bai S, Huang Y, Yao X. Plasma membrane mechanical stress activates TRPC5 channels. PLoS One 2015; 10:e0122227. [PMID: 25849346 PMCID: PMC4388645 DOI: 10.1371/journal.pone.0122227] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2014] [Accepted: 02/19/2015] [Indexed: 01/14/2023] Open
Abstract
Mechanical forces exerted on cells impose stress on the plasma membrane. Cells sense this stress and elicit a mechanoelectric transduction cascade that initiates compensatory mechanisms. Mechanosensitive ion channels in the plasma membrane are responsible for transducing the mechanical signals to electrical signals. However, the mechanisms underlying channel activation in response to mechanical stress remain incompletely understood. Transient Receptor Potential (TRP) channels serve essential functions in several sensory modalities. These channels can also participate in mechanotransduction by either being autonomously sensitive to mechanical perturbation or by coupling to other mechanosensory components of the cell. Here, we investigated the response of a TRP family member, TRPC5, to mechanical stress. Hypoosmolarity triggers Ca2+ influx and cationic conductance through TRPC5. Importantly, for the first time we were able to record the stretch-activated TRPC5 current at single-channel level. The activation threshold for TRPC5 was found to be 240 mOsm for hypoosmotic stress and between −20 and −40 mmHg for pressure applied to membrane patch. In addition, we found that disruption of actin filaments suppresses TRPC5 response to hypoosmotic stress and patch pipette pressure, but does not prevent the activation of TRPC5 by stretch-independent mechanisms, indicating that actin cytoskeleton is an essential transduction component that confers mechanosensitivity to TRPC5. In summary, our findings establish that TRPC5 can be activated at the single-channel level when mechanical stress on the cell reaches a certain threshold.
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Affiliation(s)
- Bing Shen
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
- Department of Physiology, Anhui Medical University, Hefei, China
| | - Ching-On Wong
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
- * E-mail: (XY); (CW)
| | - On-Chai Lau
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Theodosia Woo
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Suwen Bai
- Department of Physiology, Anhui Medical University, Hefei, China
| | - Yu Huang
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
| | - Xiaoqiang Yao
- School of Biomedical Sciences, Faculty of Medicine, the Chinese University of Hong Kong, Shatin, Hong Kong, China
- * E-mail: (XY); (CW)
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15
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Ando C, Liu N, Yoshimura K. A cytoplasmic helix is required for pentamer formation of the Escherichia coli MscL mechanosensitive channel. J Biochem 2015; 158:109-14. [PMID: 25697390 DOI: 10.1093/jb/mvv019] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Accepted: 01/14/2015] [Indexed: 01/01/2023] Open
Abstract
Many membrane proteins such as ion channels are oligomers, but the determinants of the degree of oligomerization are not fully understood. Mechanosensitive channel with large conductance (MscL), which is ubiquitous in bacteria, is a homopentamer with two transmembrane helices and a cytoplasmic helix in each subunit. The carboxyl-terminal cytoplasmic helices assemble into a pentameric bundle that resembles cartilage oligomeric matrix protein. To address the role of cytoplasmic helices in the pentamer formation of Escherichia coli MscL, we generated MscL constructs with various deletions at the carboxyl terminus and translated them in a cell-free system. Deletions of Leu-129 and the downstream sequence resulted in formation of various oligomers without preference to pentamers, suggesting that nearly the whole cytoplasmic helix is required for MscL pentamer formation.
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Affiliation(s)
- Chie Ando
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan
| | - Naili Liu
- Department of Biology, University of Maryland, 1210 Biology-Psychology Bldg., College Park, MD 20742, USA; and
| | - Kenjiro Yoshimura
- Graduate School of Life and Environmental Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8572, Japan; Department of Biology, University of Maryland, 1210 Biology-Psychology Bldg., College Park, MD 20742, USA; and Department of Machinery and Control Systems, Shibaura Institute of Technology, 307 Fukasaku, Minuma-ku, Saitama-shi, Saitama 337-8570, Japan
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16
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Turina AV, Clop PD, Perillo MA. Synaptosomal membrane-based Langmuir-Blodgett films: a platform for studies on γ-aminobutyric acid type A receptor binding properties. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:1792-1801. [PMID: 25594402 DOI: 10.1021/la5042986] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
In this work we used Langmuir-Blodgett films (LB) as model membranes to study the effect of molecular packing on the flunitrazepam (FNZ) accessibility to the binding sites at the GABAA receptor (GABAA-R). Ligand binding data were correlated with film topography analysis by atomic force microscopy images (AFM) and SDS-PAGE. Langmuir films (LF) were prepared by the spreading of synaptosomal membranes (SM) from bovine brain cortex at the air-water interface. LBs were obtained by the transference, at 15 or 35 mN/m constant surface pressure (π), of one (LB15/1c and LB35/1c) or two (LB35/2c) LFs to a film-free hydrophobic alkylated substrate (CONglass). Transference was performed in a serial manner, which allowed the accumulation of a great number of samples. SDS-PAGE clearly showed a 55 kDa band characteristic of GABAA-R subunits. Detrended fluctuation analysis of topographic data from AFM images exhibited a single slope value (self-similarity parameter α) in CONglass and a discontinuous slope change in the α value at an autocorrelation length of ∼100 nm in all LB samples, supporting the LF transference to the substrate. AFM images of CONglass and LB15/1c exhibited roughness and average heights that were similar between measurements and significantly lower than those of LB35/1c and LB35/2c, suggesting that the substrate coverage in the latter was more stable than in LB15/1c. While [(3)H]FNZ binding in LB15/1c did not reach saturation, in LB35/1c the binding kinetics became sigmoid with a binding affinity lower than in the SM suspension. Our results highlight the π dependence of both binding and topological data and call to mind the receptor mechanosensitivity. Thus, LB films provide a tool for bionanosensing GABAA-R ligand binding as well as GABAA-R activity modulation induced by the environmental supramolecular organization.
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Affiliation(s)
- Anahí V Turina
- Instituto de Investigaciones Biológicas y Tecnológicas, IIByT, (CONICET- UNC), Cátedra de Química Biológica, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba , Av. Vélez Sarsfield 1611, 5016 Córdoba, Argentina
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17
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Yano H, Choudhury ME, Islam A, Kobayashi K, Tanaka J. Cellular mechanotransduction of physical force and organ response to exercise-induced mechanical stimuli. THE JOURNAL OF PHYSICAL FITNESS AND SPORTS MEDICINE 2015. [DOI: 10.7600/jpfsm.4.83] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/08/2023]
Affiliation(s)
- Hajime Yano
- Department of Molecular and Cellular Physiology, Ehime University Graduate School of Medicine
| | - Mohammed E Choudhury
- Department of Molecular and Cellular Physiology, Ehime University Graduate School of Medicine
| | - Afsana Islam
- Department of Molecular and Cellular Physiology, Ehime University Graduate School of Medicine
| | - Kana Kobayashi
- Department of Molecular and Cellular Physiology, Ehime University Graduate School of Medicine
| | - Junya Tanaka
- Department of Molecular and Cellular Physiology, Ehime University Graduate School of Medicine
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18
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Sokabe M, Sawada Y, Kobayashi T. Ion Channels Activated by Mechanical Forces in Bacterial and Eukaryotic Cells. Subcell Biochem 2015; 72:613-26. [PMID: 26174401 DOI: 10.1007/978-94-017-9918-8_28] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022]
Abstract
Since the first discovery of mechanosensitive ion channel (MSC) in non-sensory cells in 1984, a variety of MSCs has been identified both in prokaryotic and eukaryotic cells. One of the central issues concerning MSCs is to understand the molecular and biophysical mechanisms of how mechanical forces activate/open MSCs. It has been well established that prokaryotic (mostly bacterial) MSCs are activated exclusively by membrane tension. Thus the problem to be solved with prokaryotic MSCs is the mechanisms how the MSC proteins receive tensile forces from the lipid bilayer and utilize them for channel opening. On the other hand, the activation of many eukaryotic MSCs crucially depends on tension in the actin cytoskeleton. By using the actin cytoskeleton as a force sensing antenna, eukaryotic MSCs have obtained sophisticated functions such as remote force sensing and force-direction sensing, which bacterial MSCs do not have. Actin cytoskeletons also give eukaryotic MSCs an interesting and important function called "active touch sensing", by which cells can sense rigidity of their substrates. The contractile actin cytoskeleton stress fiber (SF) anchors its each end to a focal adhesion (FA) and pulls the substrate to generate substrate-rigidity-dependent stresses in the FA. It has been found that those stresses are sensed by some Ca2+-permeable MSCs existing in the vicinity of FAs, thus the MSCs work as a substrate rigidity sensor that can transduce the rigidity into intracellular Ca2+ levels. This short review, roughly constituting of two parts, deals with molecular and biophysical mechanisms underlying the MSC activation process mostly based on our recent studies; (1) structure-function in bacterial MSCs activation at the atomic level, and (2) roles of actin cytoskeletons in the activation of eukaryotic MSCs.
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Affiliation(s)
- Masahiro Sokabe
- Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya, Japan,
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19
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Steward AJ, Kelly DJ. Mechanical regulation of mesenchymal stem cell differentiation. J Anat 2014; 227:717-31. [PMID: 25382217 DOI: 10.1111/joa.12243] [Citation(s) in RCA: 158] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/08/2014] [Indexed: 12/18/2022] Open
Abstract
Biophysical cues play a key role in directing the lineage commitment of mesenchymal stem cells or multipotent stromal cells (MSCs), but the mechanotransductive mechanisms at play are still not fully understood. This review article first describes the roles of both substrate mechanics (e.g. stiffness and topography) and extrinsic mechanical cues (e.g. fluid flow, compression, hydrostatic pressure, tension) on the differentiation of MSCs. A specific focus is placed on the role of such factors in regulating the osteogenic, chondrogenic, myogenic and adipogenic differentiation of MSCs. Next, the article focuses on the cellular components, specifically integrins, ion channels, focal adhesions and the cytoskeleton, hypothesized to be involved in MSC mechanotransduction. This review aims to illustrate the strides that have been made in elucidating how MSCs sense and respond to their mechanical environment, and also to identify areas where further research is needed.
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Affiliation(s)
- Andrew J Steward
- Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin, Ireland.,Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland.,Department of Aerospace and Mechanical Engineering, Bioengineering Graduate Program, University of Notre Dame, Notre Dame, IN, USA
| | - Daniel J Kelly
- Department of Mechanical and Manufacturing Engineering, School of Engineering, Trinity College Dublin, Dublin, Ireland.,Trinity Centre for Bioengineering, Trinity Biomedical Sciences Institute, Trinity College Dublin, Dublin, Ireland.,Advanced Materials and Bioengineering Research Centre (AMBER), Trinity College Dublin, Dublin, Ireland
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20
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Jakob U, Kriwacki R, Uversky VN. Conditionally and transiently disordered proteins: awakening cryptic disorder to regulate protein function. Chem Rev 2014; 114:6779-805. [PMID: 24502763 PMCID: PMC4090257 DOI: 10.1021/cr400459c] [Citation(s) in RCA: 145] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Affiliation(s)
- Ursula Jakob
- Department of Molecular, Cellular and Developmental Biology, University of Michigan, Ann Arbor, Michigan 48109-1048, United States
| | - Richard Kriwacki
- Department of Structural Biology, St. Jude Children’s Research Hospital, Memphis, Tennessee 38105, United States
- Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee 38163, United States
| | - Vladimir N. Uversky
- Department of Molecular Medicine, University of South Florida, Tampa, Florida 33612, United States
- Institute for Biological Instrumentation, Russian Academy of Sciences, 142290 Pushchino, Moscow Region, Russia
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21
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Mukherjee N, Jose MD, Birkner JP, Walko M, Ingólfsson HI, Dimitrova A, Arnarez C, Marrink SJ, Koçer A. The activation mode of the mechanosensitive ion channel, MscL, by lysophosphatidylcholine differs from tension-induced gating. FASEB J 2014; 28:4292-302. [PMID: 24958207 DOI: 10.1096/fj.14-251579] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
One of the best-studied mechanosensitive channels is the mechanosensitive channel of large conductance (MscL). MscL senses tension in the membrane evoked by an osmotic down shock and directly couples it to large conformational changes leading to the opening of the channel. Spectroscopic techniques offer unique possibilities to monitor these conformational changes if it were possible to generate tension in the lipid bilayer, the native environment of MscL, during the measurements. To this end, asymmetric insertion of l-α-lysophosphatidylcholine (LPC) into the lipid bilayer has been effective; however, how LPC activates MscL is not fully understood. Here, the effects of LPC on tension-sensitive mutants of a bacterial MscL and on MscL homologs with different tension sensitivities are reported, leading to the conclusion that the mode of action of LPC is different from that of applied tension. Our results imply that LPC shifts the free energy of gating by interfering with MscL-membrane coupling. Furthermore, we demonstrate that the fine-tuned addition of LPC can be used for controlled activation of MscL in spectroscopic studies.
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Affiliation(s)
- Nobina Mukherjee
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Mac Donald Jose
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Jan Peter Birkner
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands; Zernike Institute for Advanced Materials, University of Groningen, Groningen, The Netherlands; and
| | - Martin Walko
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Helgi I Ingólfsson
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Anna Dimitrova
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Clément Arnarez
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Siewert J Marrink
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands
| | - Armağan Koçer
- Groningen Biomolecular Sciences and Biotechnology Institute, Groningen, The Netherlands; Neuroscience Department, University Medical Centre Groningen, Groningen, The Netherlands
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22
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Koshy C, Ziegler C. Structural insights into functional lipid-protein interactions in secondary transporters. Biochim Biophys Acta Gen Subj 2014; 1850:476-87. [PMID: 24859688 DOI: 10.1016/j.bbagen.2014.05.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 05/09/2014] [Accepted: 05/12/2014] [Indexed: 12/22/2022]
Abstract
BACKGROUND Structural evidences with functional corroborations have revealed distinct features of lipid-protein interactions especially in channels and receptors. Many membrane embedded transporters are also known to require specific lipids for their functions and for some of them cellular and biochemical data suggest tight regulation by the lipid bilayer. However, molecular details on lipid-protein interactions in transporters are sparse since lipids are either depleted from the detergent solubilized transporters in three-dimensional crystals or not readily resolved in crystal structures. Nevertheless the steady increase in the progress of transporter structure determination contributed more examples of structures with resolved lipids. SCOPE OF REVIEW This review gives an overview on transporter structures in complex with lipids reported to date and discusses commonly encountered difficulties in the identification of functionally significant lipid-protein interactions based on those structures and functional in vitro data. Recent structures provided molecular details into regulation mechanism of transporters by specific lipids. The review highlights common findings and conserved patterns for distantly related transporter families to draw a more general picture on the regulatory role of lipid-protein interactions. MAJOR CONCLUSIONS Several common themes of the manner in which lipids directly influence membrane-mediated folding, oligomerization and structure stability can be found. Especially for LeuT-like fold transporters similarities in structurally resolved lipid-protein interactions suggest a common way in which transporter conformations are affected by lipids even in evolutionarily distinct transporters. Lipids appear to play an additional role as joints mechanically reinforcing the inverted repeat topology, which is a major determinant in the alternating access mechanism of secondary transporters. GENERAL SIGNIFICANCE This review brings together and adds to the repertoire of knowledge on lipid-protein interactions of functional significance presented in structures of membrane transporters. Knowledge of specific lipid-binding sites and modes of lipid influence on these proteins not only accomplishes the molecular description of transport cycle further, but also sheds light into localization dependent differences of transporter function. This article is part of a Special Issue entitled Structural biochemistry and biophysics of membrane proteins.
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Affiliation(s)
- Caroline Koshy
- Max Planck Institute of Biophysics, Structural Biology Department, Frankfurt am Main, Germany; Max-Planck Institute of Biophysics, Computational Structural Biology Group, Frankfurt am Main, Germany
| | - Christine Ziegler
- Max Planck Institute of Biophysics, Structural Biology Department, Frankfurt am Main, Germany; Institute of Biophysics and Physical Biochemistry, University of Regensburg, Regensburg, Germany.
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23
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Yoo S, Lim JY, Hwang SW. Sensory TRP channel interactions with endogenous lipids and their biological outcomes. Molecules 2014; 19:4708-44. [PMID: 24739932 PMCID: PMC6271031 DOI: 10.3390/molecules19044708] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 04/08/2014] [Accepted: 04/08/2014] [Indexed: 01/30/2023] Open
Abstract
Lipids have long been studied as constituents of the cellular architecture and energy stores in the body. Evidence is now rapidly growing that particular lipid species are also important for molecular and cellular signaling. Here we review the current information on interactions between lipids and transient receptor potential (TRP) ion channels in nociceptive sensory afferents that mediate pain signaling. Sensory neuronal TRP channels play a crucial role in the detection of a variety of external and internal changes, particularly with damaging or pain-eliciting potentials that include noxiously high or low temperatures, stretching, and harmful substances. In addition, recent findings suggest that TRPs also contribute to altering synaptic plasticity that deteriorates chronic pain states. In both of these processes, specific lipids are often generated and have been found to strongly modulate TRP activities, resulting primarily in pain exacerbation. This review summarizes three standpoints viewing those lipid functions for TRP modulations as second messengers, intercellular transmitters, or bilayer building blocks. Based on these hypotheses, we discuss perspectives that account for how the TRP-lipid interaction contributes to the peripheral pain mechanism. Still a number of blurred aspects remain to be examined, which will be answered by future efforts and may help to better control pain states.
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Affiliation(s)
- Sungjae Yoo
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 136-705, Korea.
| | - Ji Yeon Lim
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 136-705, Korea.
| | - Sun Wook Hwang
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul 136-705, Korea.
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24
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Retailleau K, Duprat F. Polycystins and partners: proposed role in mechanosensitivity. J Physiol 2014; 592:2453-71. [PMID: 24687583 DOI: 10.1113/jphysiol.2014.271346] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mutations of the two polycystins, PC1 and PC2, lead to polycystic kidney disease. Polycystins are able to form complexes with numerous families of proteins that have been suggested to participate in mechanical sensing. The proposed role of polycystins and their partners in the kidney primary cilium is to sense urine flow. A role for polycystins in mechanosensing has also been shown in other cell types such as vascular smooth muscle cells and cardiac myocytes. At the plasma membrane, polycystins interact with diverse ion channels of the TRP family and with stretch-activated channels (Piezos, TREKs). The actin cytoskeleton and its interacting proteins, such as filamin A, have been shown to be essential for these interactions. Numerous proteins involved in cell-cell and cell-extracellular matrix junctions interact with PC1 and/or PC2. These multimeric protein complexes are important for cell structure integrity, the transmission of force, as well as for mechanosensing and mechanotransduction. A group of polycystin partners are also involved in subcellular trafficking mechanisms. Finally, PC1 and especially PC2 interact with elements of the endoplasmic reticulum and are essential components of calcium homeostasis. In conclusion, we propose that both PC1 and PC2 act as conductors to tune the overall cellular mechanosensitivity.
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Affiliation(s)
- Kevin Retailleau
- CNRS Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne, France
| | - Fabrice Duprat
- CNRS Institute of Molecular and Cellular Pharmacology (IPMC), Valbonne, France
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25
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Lima WC, Vinet A, Pieters J, Cosson P. Role of PKD2 in rheotaxis in Dictyostelium. PLoS One 2014; 9:e88682. [PMID: 24520414 PMCID: PMC3919814 DOI: 10.1371/journal.pone.0088682] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 01/08/2014] [Indexed: 11/18/2022] Open
Abstract
The sensing of mechanical forces modulates several cellular responses as adhesion, migration and differentiation. Transient elevations of calcium concentration play a key role in the activation of cells following mechanical stress, but it is still unclear how eukaryotic cells convert a mechanical signal into an ion flux. In this study, we used the model organism Dictyostelium discoideum to assess systematically the role of individual calcium channels in mechanosensing. Our results indicate that PKD2 is the major player in the cell response to rheotaxis (i.e., shear-flow induced mechanical motility), while other putative calcium channels play at most minor roles. Mutant pkd2 KO cells lose the ability to orient relative to a shear flow, whereas their ability to move towards a chemoattractant is unaffected. PKD2 is also important for calcium-induced lysosome exocytosis: WT cells show a transient, 2-fold increase in lysosome secretion upon sudden exposure to high levels of extracellular calcium, but pkd2 KO cells do not. In Dictyostelium, PKD2 is specifically localized at the plasma membrane, where it may generate calcium influxes in response to mechanical stress or extracellular calcium changes.
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Affiliation(s)
- Wanessa C. Lima
- Department of Cell Physiology and Metabolism, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
- * E-mail:
| | - Adrien Vinet
- Biozentrum, University of Basel, Basel, Switzerland
| | - Jean Pieters
- Biozentrum, University of Basel, Basel, Switzerland
| | - Pierre Cosson
- Department of Cell Physiology and Metabolism, Centre Médical Universitaire, University of Geneva, Geneva, Switzerland
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26
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Aguilella VM, Verdiá-Báguena C, Alcaraz A. Lipid charge regulation of non-specific biological ion channels. Phys Chem Chem Phys 2014; 16:3881-93. [DOI: 10.1039/c3cp54690j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lipid charge regulation effects in different protein–lipid conformations highlight the role of electrostatic interactions in conductance and selectivity of non-specific biological ion channels.
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Affiliation(s)
| | | | - Antonio Alcaraz
- Dept. Physics
- Lab. Molecular Biophysics
- Universitat Jaume I
- 12080 Castellón, Spain
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27
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Structural evidence for functional lipid interactions in the betaine transporter BetP. EMBO J 2013; 32:3096-105. [PMID: 24141878 DOI: 10.1038/emboj.2013.226] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 09/11/2013] [Indexed: 11/09/2022] Open
Abstract
Bilayer lipids contribute to the stability of membrane transporters and are crucially involved in their proper functioning. However, the molecular knowledge of how surrounding lipids affect membrane transport is surprisingly limited and despite its general importance is rarely considered in the molecular description of a transport mechanism. One reason is that only few atomic resolution structures of channels or transporters reveal a functional interaction with lipids, which are difficult to detect in X-ray structures per se. Overcoming these difficulties, we report here on a new structure of the osmotic stress-regulated betaine transporter BetP in complex with anionic lipids. This lipid-associated BetP structure is important in the molecular understanding of osmoregulation due to the strong dependence of activity regulation in BetP on the presence of negatively charged lipids. We detected eight resolved palmitoyl-oleoyl phosphatidyl glycerol (PG) lipids mimicking parts of the membrane leaflets and interacting with key residues in transport and regulation. The lipid-protein interactions observed here in structural detail in BetP provide molecular insights into the role of lipids in osmoregulated secondary transport.
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28
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A unifying mechanism for cancer cell death through ion channel activation by HAMLET. PLoS One 2013; 8:e58578. [PMID: 23505537 PMCID: PMC3591364 DOI: 10.1371/journal.pone.0058578] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2012] [Accepted: 02/06/2013] [Indexed: 01/16/2023] Open
Abstract
Ion channels and ion fluxes control many aspects of tissue homeostasis. During oncogenic transformation, critical ion channel functions may be perturbed but conserved tumor specific ion fluxes remain to be defined. Here we used the tumoricidal protein-lipid complex HAMLET as a probe to identify ion fluxes involved in tumor cell death. We show that HAMLET activates a non-selective cation current, which reached a magnitude of 2.74±0.88 nA within 1.43±0.13 min from HAMLET application. Rapid ion fluxes were essential for HAMLET-induced carcinoma cell death as inhibitors (amiloride, BaCl2), preventing the changes in free cellular Na+ and K+ concentrations also prevented essential steps accompanying carcinoma cell death, including changes in morphology, uptake, global transcription, and MAP kinase activation. Through global transcriptional analysis and phosphorylation arrays, a strong ion flux dependent p38 MAPK response was detected and inhibition of p38 signaling delayed HAMLET-induced death. Healthy, differentiated cells were resistant to HAMLET challenge, which was accompanied by innate immunity rather than p38-activation. The results suggest, for the first time, a unifying mechanism for the initiation of HAMLET’s broad and rapid lethal effect on tumor cells. These findings are particularly significant in view of HAMLET’s documented therapeutic efficacy in human studies and animal models. The results also suggest that HAMLET offers a two-tiered therapeutic approach, killing cancer cells while stimulating an innate immune response in surrounding healthy tissues.
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Mika JT, Birkner JP, Poolman B, Koçer A. On the role of individual subunits in MscL gating: “All for one, one for all?”. FASEB J 2012. [DOI: 10.1096/fj.12-214361] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Jacek T. Mika
- Department of BiochemistryGroningen Biomolecular Science and Biotechnology InstituteGroningenThe Netherlands
| | - Jan P. Birkner
- Department of BiochemistryGroningen Biomolecular Science and Biotechnology InstituteGroningenThe Netherlands
| | - Bert Poolman
- Department of BiochemistryGroningen Biomolecular Science and Biotechnology InstituteGroningenThe Netherlands
- Netherlands Proteomics CentreUniversity of GroningenGroningenThe Netherlands
- Zernike Institute for Advanced MaterialsUniversity of GroningenGroningenThe Netherlands
| | - Armağan Koçer
- Department of BiochemistryGroningen Biomolecular Science and Biotechnology InstituteGroningenThe Netherlands
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Rostovtseva TK, Gurnev PA, Chen MY, Bezrukov SM. Membrane lipid composition regulates tubulin interaction with mitochondrial voltage-dependent anion channel. J Biol Chem 2012; 287:29589-98. [PMID: 22763701 DOI: 10.1074/jbc.m112.378778] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Elucidating molecular mechanisms by which lipids regulate protein function within biological membranes is critical for understanding the many cellular processes. Recently, we have found that dimeric αβ-tubulin, a subunit of microtubules, regulates mitochondrial respiration by blocking the voltage-dependent anion channel (VDAC) of mitochondrial outer membrane. Here, we show that the mechanism of VDAC blockage by tubulin involves tubulin interaction with the membrane as a critical step. The on-rate of the blockage varies up to 100-fold depending on the particular lipid composition used for bilayer formation in reconstitution experiments and increases with the increasing content of dioleoylphosphatidylethanolamine (DOPE) in dioleoylphosphatidylcholine (DOPC) bilayers. At physiologically low salt concentrations, the on-rate is decreased by the charged lipid. The off-rate of VDAC blockage by tubulin does not depend on the lipid composition. Using confocal fluorescence microscopy, we compared tubulin binding to the membranes of giant unilamellar vesicles (GUVs) made from DOPC and DOPC/DOPE mixtures. We found that detectable binding of the fluorescently labeled dimeric tubulin to GUV membranes requires the presence of DOPE. We propose that prior to the characteristic blockage of VDAC, tubulin first binds to the membrane in a lipid-dependent manner. We thus reveal a new potent regulatory role of the mitochondrial lipids in control of the mitochondrial outer membrane permeability and hence mitochondrial respiration through tuning VDAC sensitivity to blockage by tubulin. More generally, our findings give an example of the lipid-controlled protein-protein interaction where the choice of lipid species is able to change the equilibrium binding constant by orders of magnitude.
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Affiliation(s)
- Tatiana K Rostovtseva
- Program in Physical Biology, Eunice Kennedy Shriver NICHD, National Institutes of Health, Bethesda, MD 20892, USA.
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Balleza D. Mechanical properties of lipid bilayers and regulation of mechanosensitive function: from biological to biomimetic channels. Channels (Austin) 2012; 6:220-33. [PMID: 22790280 DOI: 10.4161/chan.21085] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Material properties of lipid bilayers, including thickness, intrinsic curvature and compressibility regulate the function of mechanosensitive (MS) channels. This regulation is dependent on phospholipid composition, lateral packing and organization within the membrane. Therefore, a more complete framework to understand the functioning of MS channels requires insights into bilayer structure, thermodynamics and phospholipid structure, as well as lipid-protein interactions. Phospholipids and MS channels interact with each other mainly through electrostatic forces and hydrophobic matching, which are also crucial for antimicrobial peptides. They are excellent models for studying the formation and stabilization of membrane pores. Importantly, they perform equivalent responses as MS channels: (1) tilting in response to tension and (2) dissipation of osmotic gradients. Lessons learned from pore forming peptides could enrich our knowledge of mechanisms of action and evolution of these channels. Here, the current state of the art is presented and general principles of membrane regulation of mechanosensitive function are discussed.
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Affiliation(s)
- Daniel Balleza
- Unidad de Biofísica, CSIC, UPV/EHU, Universidad del País Vasco, Leioa, Spain.
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32
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Loubet B, Seifert U, Lomholt MA. Effective tension and fluctuations in active membranes. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2012; 85:031913. [PMID: 22587129 DOI: 10.1103/physreve.85.031913] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Indexed: 05/31/2023]
Abstract
We calculate the fluctuation spectrum of the shape of a lipid vesicle or cell exposed to a nonthermal source of noise. In particular, we take constraints on the membrane area and the volume of fluid that it encapsulates into account when obtaining expressions for the dependency of the membrane tension on the noise. We then investigate three possible origins of the nonthermal noise taken from the literature: A direct force, which models an external medium pushing on the membrane, a curvature force, which models a fluctuating spontaneous curvature, and a permeation force coming from an active transport of fluid through the membrane. For the direct force and curvature force cases, we compare our results to existing experiments on active membranes.
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Affiliation(s)
- Bastien Loubet
- Department of Physics, MEMPHYS-Center for Biomembrane Physics, Chemistry and Pharmacy, University of Southern Denmark, Odense M, Denmark
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33
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Smith AW. Lipid–protein interactions in biological membranes: A dynamic perspective. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2012; 1818:172-7. [DOI: 10.1016/j.bbamem.2011.06.015] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Revised: 06/21/2011] [Accepted: 06/23/2011] [Indexed: 01/31/2023]
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Malcolm HR, Heo YY, Elmore DE, Maurer JA. Defining the role of the tension sensor in the mechanosensitive channel of small conductance. Biophys J 2011; 101:345-52. [PMID: 21767486 DOI: 10.1016/j.bpj.2011.05.058] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 05/11/2011] [Accepted: 05/23/2011] [Indexed: 12/29/2022] Open
Abstract
Mutations that alter the phenotypic behavior of the Escherichia coli mechanosensitive channel of small conductance (MscS) have been identified; however, most of these residues play critical roles in the transition between the closed and open states of the channel and are not directly involved in lipid interactions that transduce the tension response. In this study, we use molecular dynamic simulations to predict critical lipid interacting residues in the closed state of MscS. The physiological role of these residues was then investigated by performing osmotic downshock assays on MscS mutants where the lipid interacting residues were mutated to alanine. These experiments identified seven residues in the first and second transmembrane helices as lipid-sensing residues. The majority of these residues are hydrophobic amino acids located near the extracellular interface of the membrane. All of these residues interact strongly with the lipid bilayer in the closed state of MscS, but do not face the bilayer directly in structures associated with the open and desensitized states of the channel. Thus, the position of these residues relative to the lipid membrane appears related to the ability of the channel to sense tension in its different physiological states.
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Affiliation(s)
- Hannah R Malcolm
- Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri, USA
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Samuli Ollila OH, Louhivuori M, Marrink SJ, Vattulainen I. Protein shape change has a major effect on the gating energy of a mechanosensitive channel. Biophys J 2011; 100:1651-9. [PMID: 21463578 PMCID: PMC3072608 DOI: 10.1016/j.bpj.2011.02.027] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2010] [Revised: 01/18/2011] [Accepted: 02/02/2011] [Indexed: 10/18/2022] Open
Abstract
Increasing experimental evidence has shown that membrane protein functionality depends on molecular composition of cell membranes. However, the origin of this dependence is not fully understood. It is reasonable to assume that specific lipid-protein interactions are important, yet more generic effects due to mechanical properties of lipid bilayers likely play a significant role too. Previously it has been demonstrated using models for elastic properties of membranes and lateral pressure profiles of lipid bilayers that the mechanical properties of a lipid bilayer can contribute as much as ∼10 k(B)T to the free energy difference associated with a change in protein conformational state. Here, we extend those previous approaches to a more realistic model for a large mechanosensitive channel (MscL). We use molecular dynamics together with the MARTINI model to simulate the open and closed states of MscL embedded in a DOPC bilayer. We introduce a procedure to calculate the mechanical energy change in the channel gating using a three-dimensional pressure distribution inside a membrane, computed from the molecular dynamics simulations. We decompose the mechanical energy to terms associated with area dilation and shape contribution. Our results highlight that the lateral pressure profile of a lipid bilayer together with the shape change in gating can induce a contribution of ∼30 k(B)T on the gating energy of MscL. This contribution arises largely from the interfacial tension between hydrophobic and hydrophilic regions in a lipid bilayer.
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Affiliation(s)
- O H Samuli Ollila
- Department of Physics, Tampere University of Technology, Tampere, Finland.
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36
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Kobayashi T, Sokabe M. Sensing substrate rigidity by mechanosensitive ion channels with stress fibers and focal adhesions. Curr Opin Cell Biol 2010; 22:669-76. [DOI: 10.1016/j.ceb.2010.08.023] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2010] [Revised: 08/27/2010] [Accepted: 08/27/2010] [Indexed: 10/19/2022]
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Affiliation(s)
- Chwee Teck Lim
- Division of Bioengineering and Department of Mechanical Engineering, National University of Singapore, Singapore 117576, Republic of Singapore.
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