1
|
Bender PA, Jayaraman V. Biophysics of protein-lipid interactions. Biophys J 2024; 123:1912-1914. [PMID: 37839410 PMCID: PMC11309976 DOI: 10.1016/j.bpj.2023.10.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 10/02/2023] [Accepted: 10/03/2023] [Indexed: 10/17/2023] Open
Abstract
The biological phenomenon of protein-lipid interactions in cell membranes underlies the diversity of peripheral membrane protein function and physical properties of the membrane. To summarize novel findings in the field, this research highlight focuses on recent publications in Biophysical Journal.
Collapse
Affiliation(s)
- Paula A Bender
- Center for Membrane Biology, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, Texas; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas
| | - Vasanthi Jayaraman
- Center for Membrane Biology, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, Texas; MD Anderson Cancer Center UTHealth Graduate School of Biomedical Sciences, University of Texas Health Science Center at Houston, Houston, Texas.
| |
Collapse
|
2
|
Michelucci A, Catacuzzeno L. Piezo1, the new actor in cell volume regulation. Pflugers Arch 2024; 476:1023-1039. [PMID: 38581527 PMCID: PMC11166825 DOI: 10.1007/s00424-024-02951-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2024] [Revised: 02/29/2024] [Accepted: 03/20/2024] [Indexed: 04/08/2024]
Abstract
All animal cells control their volume through a complex set of mechanisms, both to counteract osmotic perturbations of the environment and to enable numerous vital biological processes, such as proliferation, apoptosis, and migration. The ability of cells to adjust their volume depends on the activity of ion channels and transporters which, by moving K+, Na+, and Cl- ions across the plasma membrane, generate the osmotic gradient that drives water in and out of the cell. In 2010, Patapoutian's group identified a small family of evolutionarily conserved, Ca2+-permeable mechanosensitive channels, Piezo1 and Piezo2, as essential components of the mechanically activated current that mediates mechanotransduction in vertebrates. Piezo1 is expressed in several tissues and its opening is promoted by a wide range of mechanical stimuli, including membrane stretch/deformation and osmotic stress. Piezo1-mediated Ca2+ influx is used by the cell to convert mechanical forces into cytosolic Ca2+ signals that control diverse cellular functions such as migration and cell death, both dependent on changes in cell volume and shape. The crucial role of Piezo1 in the regulation of cell volume was first demonstrated in erythrocytes, which need to reduce their volume to pass through narrow capillaries. In HEK293 cells, increased expression of Piezo1 was found to enhance the regulatory volume decrease (RVD), the process whereby the cell re-establishes its original volume after osmotic shock-induced swelling, and it does so through Ca2+-dependent modulation of the volume-regulated anion channels. More recently we reported that Piezo1 controls the RVD in glioblastoma cells via the modulation of Ca2+-activated K+ channels. To date, however, the mechanisms through which this mechanosensitive channel controls cell volume and maintains its homeostasis have been poorly investigated and are still far from being understood. The present review aims to provide a broad overview of the literature discussing the recent advances on this topic.
Collapse
Affiliation(s)
- A Michelucci
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| | - L Catacuzzeno
- Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123, Perugia, Italy.
| |
Collapse
|
3
|
Luedke KP, Yoshino J, Yin C, Jiang N, Huang JM, Huynh K, Parrish JZ. Dendrite intercalation between epidermal cells tunes nociceptor sensitivity to mechanical stimuli in Drosophila larvae. PLoS Genet 2024; 20:e1011237. [PMID: 38662763 DOI: 10.1371/journal.pgen.1011237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2023] [Revised: 05/07/2024] [Accepted: 03/29/2024] [Indexed: 05/07/2024] Open
Abstract
An animal's skin provides a first point of contact with the sensory environment, including noxious cues that elicit protective behavioral responses. Nociceptive somatosensory neurons densely innervate and intimately interact with epidermal cells to receive these cues, however the mechanisms by which epidermal interactions shape processing of noxious inputs is still poorly understood. Here, we identify a role for dendrite intercalation between epidermal cells in tuning sensitivity of Drosophila larvae to noxious mechanical stimuli. In wild-type larvae, dendrites of nociceptive class IV da neurons intercalate between epidermal cells at apodemes, which function as body wall muscle attachment sites, but not at other sites in the epidermis. From a genetic screen we identified miR-14 as a regulator of dendrite positioning in the epidermis: miR-14 is expressed broadly in the epidermis but not in apodemes, and miR-14 inactivation leads to excessive apical dendrite intercalation between epidermal cells. We found that miR-14 regulates expression and distribution of the epidermal Innexins ogre and Inx2 and that these epidermal gap junction proteins restrict epidermal dendrite intercalation. Finally, we found that altering the extent of epidermal dendrite intercalation had corresponding effects on nociception: increasing epidermal intercalation sensitized larvae to noxious mechanical inputs and increased mechanically evoked calcium responses in nociceptive neurons, whereas reducing epidermal dendrite intercalation had the opposite effects. Altogether, these studies identify epidermal dendrite intercalation as a mechanism for mechanical coupling of nociceptive neurons to the epidermis, with nociceptive sensitivity tuned by the extent of intercalation.
Collapse
Affiliation(s)
- Kory P Luedke
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Jiro Yoshino
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Chang Yin
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Nan Jiang
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Jessica M Huang
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Kevin Huynh
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| | - Jay Z Parrish
- Department of Biology, University of Washington, Seattle, Washington State, United States of America
| |
Collapse
|
4
|
Li S, Wu B, Luo YL, Han W. Simulations of Functional Motions of Super Large Biomolecules with a Mixed-Resolution Model. J Chem Theory Comput 2024; 20:2228-2245. [PMID: 38374639 PMCID: PMC10938502 DOI: 10.1021/acs.jctc.3c01046] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Revised: 01/18/2024] [Accepted: 01/29/2024] [Indexed: 02/21/2024]
Abstract
Many large protein machines function through an interplay between large-scale movements and intricate conformational changes. Understanding functional motions of these proteins through simulations becomes challenging for both all-atom and coarse-grained (CG) modeling techniques because neither approach alone can readily capture the full details of these motions. In this study, we develop a multiscale model by employing the popular MARTINI CG model to represent a heterogeneous environment and structurally stable proteins and using the united-atom (UA) model PACE to describe proteins undergoing subtle conformational changes. PACE was previously developed to be compatible with the MARTINI solvent and membrane. Here, we couple the protein descriptions of the two models by directly mixing UA and CG interaction parameters to greatly simplify parameter determination. Through extensive validations with diverse protein systems in solution or membrane, we demonstrate that only additional parameter rescaling is needed to enable the resulting model to recover the stability of native structures of proteins under mixed representation. Moreover, we identify the optimal scaling factors that can be applied to various protein systems, rendering the model potentially transferable. To further demonstrate its applicability for realistic systems, we apply the model to a mechanosensitive ion channel Piezo1 that has peripheral arms for sensing membrane tension and a central pore for ion conductance. The model can reproduce the coupling between Piezo1's large-scale arm movement and subtle pore opening in response to membrane stress while consuming much less computational costs than all-atom models. Therefore, our model shows promise for studying functional motions of large protein machines.
Collapse
Affiliation(s)
- Shu Li
- Centre
for Artificial Intelligence Driven Drug Discovery, Faculty of Applied
Sciences, Macao Polytechnic University, Macao 999078, China
- State
Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key
Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Bohua Wu
- State
Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key
Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Yun Lyna Luo
- Department
of Biotechnology and Pharmaceutical Sciences, Western University of Health Sciences, Pomona, California 91766, United States
| | - Wei Han
- State
Key Laboratory of Chemical Oncogenomics, Guangdong Provincial Key
Laboratory of Chemical Genomics, School of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate School, Shenzhen 518055, China
- Department
of Chemistry, Faculty of Science, Hong Kong
Baptist University, Hong Kong SAR 999077, China
- Shenzhen
Bay Laboratory, Institute of Chemical Biology, Shenzhen 518132, China
| |
Collapse
|
5
|
Jiang W, Wijerathne TD, Zhang H, Lin YC, Jo S, Im W, Lacroix JJ, Luo YL. Structural and thermodynamic framework for PIEZO1 modulation by small molecules. Proc Natl Acad Sci U S A 2023; 120:e2310933120. [PMID: 38060566 PMCID: PMC10723123 DOI: 10.1073/pnas.2310933120] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/12/2023] [Indexed: 12/17/2023] Open
Abstract
Mechanosensitive PIEZO channels constitute potential pharmacological targets for multiple clinical conditions, spurring the search for potent chemical PIEZO modulators. Among them is Yoda1, a widely used synthetic small molecule PIEZO1 activator discovered through cell-based high-throughput screening. Yoda1 is thought to bind to PIEZO1's mechanosensory arm domain, sandwiched between two transmembrane regions near the channel pore. However, how the binding of Yoda1 to this region promotes channel activation remains elusive. Here, we first demonstrate that cross-linking PIEZO1 repeats A and B with disulfide bridges reduces the effects of Yoda1 in a redox-dependent manner, suggesting that Yoda1 acts by perturbing the contact between these repeats. Using molecular dynamics-based absolute binding free energy simulations, we next show that Yoda1 preferentially occupies a deeper, amphipathic binding site with higher affinity in PIEZO1 open state. Using Yoda1's binding poses in open and closed states, relative binding free energy simulations were conducted in the membrane environment, recapitulating structure-activity relationships of known Yoda1 analogs. Through virtual screening of an 8 million-compound library using computed fragment maps of the Yoda1 binding site, we subsequently identified two chemical scaffolds with agonist activity toward PIEZO1. This study supports a pharmacological model in which Yoda1 activates PIEZO1 by wedging repeats A and B, providing a structural and thermodynamic framework for the rational design of PIEZO1 modulators. Beyond PIEZO channels, the three orthogonal computational approaches employed here represent a promising path toward drug discovery in highly heterogeneous membrane protein systems.
Collapse
Affiliation(s)
- Wenjuan Jiang
- Department of Biotechnology and Pharmaceutical Sciences, Western University of Health Sciences, Pomona, CA91766
| | - Tharaka D. Wijerathne
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA91766
| | - Han Zhang
- Department of Biological Sciences, Lehigh University, Bethlehem, PA18015
- Department of Chemistry, Lehigh University, Bethlehem, PA18015
- Department of Bioengineering, Lehigh University, Bethlehem, PA18015
- Department of Computer Science and Engineering, Lehigh University, Bethlehem, PA18015
| | - Yi-Chun Lin
- Department of Biotechnology and Pharmaceutical Sciences, Western University of Health Sciences, Pomona, CA91766
| | - Sunhwan Jo
- Department of Pharmaceutical Sciences, University of Maryland, Baltimore, MD21201
| | - Wonpil Im
- Department of Biological Sciences, Lehigh University, Bethlehem, PA18015
- Department of Chemistry, Lehigh University, Bethlehem, PA18015
- Department of Bioengineering, Lehigh University, Bethlehem, PA18015
- Department of Computer Science and Engineering, Lehigh University, Bethlehem, PA18015
| | - Jerome J. Lacroix
- Department of Basic Medical Sciences, Western University of Health Sciences, Pomona, CA91766
| | - Yun L. Luo
- Department of Biotechnology and Pharmaceutical Sciences, Western University of Health Sciences, Pomona, CA91766
| |
Collapse
|
6
|
Peussa H, Fedele C, Tran H, Marttinen M, Fadjukov J, Mäntylä E, Priimägi A, Nymark S, Ihalainen TO. Light-Induced Nanoscale Deformation in Azobenzene Thin Film Triggers Rapid Intracellular Ca 2+ Increase via Mechanosensitive Cation Channels. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2206190. [PMID: 37946608 PMCID: PMC10724422 DOI: 10.1002/advs.202206190] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 09/15/2023] [Indexed: 11/12/2023]
Abstract
Epithelial cells are in continuous dynamic biochemical and physical interaction with their extracellular environment. Ultimately, this interplay guides fundamental physiological processes. In these interactions, cells generate fast local and global transients of Ca2+ ions, which act as key intracellular messengers. However, the mechanical triggers initiating these responses have remained unclear. Light-responsive materials offer intriguing possibilities to dynamically modify the physical niche of the cells. Here, a light-sensitive azobenzene-based glassy material that can be micropatterned with visible light to undergo spatiotemporally controlled deformations is used. Real-time monitoring of consequential rapid intracellular Ca2+ signals reveals that the mechanosensitive cation channel Piezo1 has a major role in generating the Ca2+ transients after nanoscale mechanical deformation of the cell culture substrate. Furthermore, the studies indicate that Piezo1 preferably responds to shear deformation at the cell-material interphase rather than to absolute topographical change of the substrate. Finally, the experimentally verified computational model suggests that Na+ entering alongside Ca2+ through the mechanosensitive cation channels modulates the duration of Ca2+ transients, influencing differently the directly stimulated cells and their neighbors. This highlights the complexity of mechanical signaling in multicellular systems. These results give mechanistic understanding on how cells respond to rapid nanoscale material dynamics and deformations.
Collapse
Affiliation(s)
- Heidi Peussa
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Chiara Fedele
- Faculty of Engineering and Natural SciencesTampere UniversityKorkeakoulunkatu 3Tampere33720Finland
| | - Huy Tran
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Mikael Marttinen
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Julia Fadjukov
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Elina Mäntylä
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Arri Priimägi
- Faculty of Engineering and Natural SciencesTampere UniversityKorkeakoulunkatu 3Tampere33720Finland
| | - Soile Nymark
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| | - Teemu O. Ihalainen
- BioMediTechFaculty of Medicine and Health TechnologyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
- Tampere Institute for Advanced StudyTampere UniversityArvo Ylpön katu 34Tampere33520Finland
| |
Collapse
|
7
|
Li C, Yu P, Wang Z, Long C, Xiao C, Xing J, Dong B, Zhai J, Zhou L, Zhou Z, Wang Y, Zhu W, Tan G, Ning C, Zhou Y, Mao C. Electro-mechanical coupling directs endothelial activities through intracellular calcium ion deployment. MATERIALS HORIZONS 2023; 10:4903-4913. [PMID: 37750251 DOI: 10.1039/d3mh01049j] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/27/2023]
Abstract
Conversion between mechanical and electrical cues is usually considered unidirectional in cells with cardiomyocytes being an exception. Here, we discover a material-induced external electric field (Eex) triggers an electro-mechanical coupling feedback loop in cells other than cardiomyocytes, human umbilical vein endothelial cells (HUVECs), by opening their mechanosensitive Piezo1 channels. When HUVECs are cultured on patterned piezoelectric materials, the materials generate Eex (confined at the cellular scale) to polarize intracellular calcium ions ([Ca2+]i), forming a built-in electric field (Ein) opposing Eex. Furthermore, the [Ca2+]i polarization stimulates HUVECs to shrink their cytoskeletons, activating Piezo1 channels to induce influx of extracellular Ca2+ that gradually increases Ein to balance Eex. Such an electro-mechanical coupling feedback loop directs pre-angiogenic activities such as alignment, elongation, and migration of HUVECs. Activated calcium dynamics during the coupling further modulate the downstream angiogenesis-inducing eNOS/NO pathway. These findings lay a foundation for developing new ways of electrical stimulation-based disease treatment.
Collapse
Affiliation(s)
- Changhao Li
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, China
| | - Peng Yu
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Zhengao Wang
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Cheng Long
- School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Cairong Xiao
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Jun Xing
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Binbin Dong
- School of Life Sciences, South China Normal University, Guangzhou 510631, China
| | - Jinxia Zhai
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Lei Zhou
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Zhengnan Zhou
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Yan Wang
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, China
| | - Wenjun Zhu
- Hospital of Stomatology, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou, 510055, China
| | - Guoxin Tan
- School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, 510006, China
| | - Chengyun Ning
- School of Material Science and Engineering & National Engineering Research Center for Tissue Restoration and Reconstruction, South China University of Technology, Guangzhou 510006, China.
| | - Yahong Zhou
- CAS Key Laboratory of Bio-inspired Materials and Interfacial Science, Technical Institute of Physics and Chemistry, Chinese Academy of Science, Beijing 100190, China.
| | - Chuanbin Mao
- Department of Biomedical Engineering, The Chinese University of Hong Kong, Sha Tin, Hong Kong SAR, China.
- School of Materials Science & Engineering, Zhejiang University, Hangzhou, 310027, China
| |
Collapse
|
8
|
Zhu H, He W, Ye P, Chen J, Wu X, Mu X, Wu Y, Pang H, Han F, Nie X. Piezo1 in skin wound healing and related diseases: Mechanotransduction and therapeutic implications. Int Immunopharmacol 2023; 123:110779. [PMID: 37582313 DOI: 10.1016/j.intimp.2023.110779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 08/04/2023] [Accepted: 08/06/2023] [Indexed: 08/17/2023]
Abstract
Skin wound healing is a multifaceted and intricate process involving inflammation, tissue proliferation, and scar formation, all of which are accompanied by the continuous application of mechanical forces. Mechanotransduction is the mechanism by which the skin receives and reacts to physical signals from the internal and external environment, converting them into intracellular biochemical signals. This intricate process relies on specialized proteins known as mechanotransducers, with Piezo1 being a critical mechanosensitive ion channel that plays a central role in this process. This article provides an overview of the structural characteristics of Piezo1 and summarizes its effects on corresponding cells or tissues at different stages of skin trauma, including how it regulates skin sensation and skin-related diseases. The aim is to reveal the potential diagnostic and therapeutic value of Piezo1 in skin trauma and skin-related diseases. Piezo1 has been reported to be a vital mediator of mechanosensation and transduction in various organs and tissues. Given its high expression in the skin, Piezo1, as a significant cell membrane ion channel, is essential in activating intracellular signaling cascades that trigger several cellular physiological functions, including cell migration and muscle contraction. These functions contribute to the regulation and improvement of wound healing.
Collapse
Affiliation(s)
- Huan Zhu
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Wenjie He
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Penghui Ye
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Jitao Chen
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Xingqian Wu
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Xingrui Mu
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China.
| | - Youzhi Wu
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland (UQ), Brisbane, QLD 4072, Australia.
| | - Huiwen Pang
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland (UQ), Brisbane, QLD 4072, Australia.
| | - Felicity Han
- Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland (UQ), Brisbane, QLD 4072, Australia.
| | - Xuqiang Nie
- College of Pharmacy, Zunyi Medical University, Zunyi 563006, China; Key Lab of the Basic Pharmacology of the Ministry of Education & Joint International Research Laboratory of Ethnomedicine of Ministry of Education, Zunyi Medical University, Zunyi 563006, China; School Medical Office, Zunyi Medical University, Zunyi 563006, China; Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland (UQ), Brisbane, QLD 4072, Australia; School of Biomedical Sciences, Translational Research Institute (TRI), Queensland University of Technology (QUT), Brisbane, QLD 4102, Australia.
| |
Collapse
|
9
|
Kwak K, Sohn H, George R, Torgbor C, Manzella-Lapeira J, Brzostowski J, Pierce SK. B cell responses to membrane-presented antigens require the function of the mechanosensitive cation channel Piezo1. Sci Signal 2023; 16:eabq5096. [PMID: 37751477 PMCID: PMC10691204 DOI: 10.1126/scisignal.abq5096] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 09/05/2023] [Indexed: 09/28/2023]
Abstract
The demand for a vaccine for coronavirus disease 2019 (COVID-19) highlighted gaps in our understanding of the requirements for B cell responses to antigens, particularly to membrane-presented antigens, as occurs in vivo. We found that human B cell responses to membrane-presented antigens required the function of Piezo1, a plasma membrane mechanosensitive cation channel. Simply making contact with a glass probe induced calcium (Ca2+) fluxes in B cells that were blocked by the Piezo1 inhibitor GsMTx4. When placed on glass surfaces, the plasma membrane tension of B cells increased, which stimulated Ca2+ influx and spreading of B cells over the glass surface, which was blocked by the Piezo1 inhibitor OB-1. B cell responses to membrane-presented antigens but not to soluble antigens were inhibited both by Piezo1 inhibitors and by siRNA-mediated knockdown of Piezo1. Thus, the activation of Piezo1 defines an essential event in B cell activation to membrane-presented antigens that may be exploited to improve the efficacy of vaccines.
Collapse
Affiliation(s)
- Kihyuck Kwak
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
- Department of Microbiology and Immunology, Institute for Immunology and Immunological Diseases, Brain Korea 21 PLUS Project for Medical Science, Yonsei University College of Medicine, Seoul 03722, Korea
| | - Haewon Sohn
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Rachel George
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Charles Torgbor
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Javier Manzella-Lapeira
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Joseph Brzostowski
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| | - Susan K. Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20852, USA
| |
Collapse
|
10
|
Luedke KP, Yoshino J, Yin C, Jiang N, Huang JM, Huynh K, Parrish JZ. Dendrite intercalation between epidermal cells tunes nociceptor sensitivity to mechanical stimuli in Drosophila larvae. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.14.557275. [PMID: 37745567 PMCID: PMC10515945 DOI: 10.1101/2023.09.14.557275] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/26/2023]
Abstract
An animal's skin provides a first point of contact with the sensory environment, including noxious cues that elicit protective behavioral responses. Nociceptive somatosensory neurons densely innervate and intimately interact with epidermal cells to receive these cues, however the mechanisms by which epidermal interactions shape processing of noxious inputs is still poorly understood. Here, we identify a role for dendrite intercalation between epidermal cells in tuning sensitivity of Drosophila larvae to noxious mechanical stimuli. In wild-type larvae, dendrites of nociceptive class IV da neurons intercalate between epidermal cells at apodemes, which function as body wall muscle attachment sites, but not at other sites in the epidermis. From a genetic screen we identified miR-14 as a regulator of dendrite positioning in the epidermis: miR-14 is expressed broadly in the epidermis but not in apodemes, and miR-14 inactivation leads to excessive apical dendrite intercalation between epidermal cells. We found that miR-14 regulates expression and distribution of the epidermal Innexins ogre and Inx2 and that these epidermal gap junction proteins restrict epidermal dendrite intercalation. Finally, we found that altering the extent of epidermal dendrite intercalation had corresponding effects on nociception: increasing epidermal intercalation sensitized larvae to noxious mechanical inputs and increased mechanically evoked calcium responses in nociceptive neurons, whereas reducing epidermal dendrite intercalation had the opposite effects. Altogether, these studies identify epidermal dendrite intercalation as a mechanism for mechanical coupling of nociceptive neurons to the epidermis, with nociceptive sensitivity tuned by the extent of intercalation.
Collapse
Affiliation(s)
- Kory P. Luedke
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Jiro Yoshino
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Chang Yin
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Nan Jiang
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Jessica M. Huang
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Kevin Huynh
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| | - Jay Z. Parrish
- Department of Biology, University of Washington, Campus Box 351800, Seattle, WA 98195, USA
| |
Collapse
|
11
|
Ozkan AD, Wijerathne TD, Gettas T, Lacroix JJ. Force-induced motions of the PIEZO1 blade probed with fluorimetry. Cell Rep 2023; 42:112837. [PMID: 37471225 PMCID: PMC10530446 DOI: 10.1016/j.celrep.2023.112837] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 06/15/2023] [Accepted: 07/05/2023] [Indexed: 07/22/2023] Open
Abstract
Mechanical forces are thought to activate mechanosensitive PIEZO channels by changing the conformation of a large transmembrane blade domain. Yet, whether different stimuli induce identical conformational changes in this domain remains unclear. Here, we repurpose a cyclic permuted green fluorescent protein as a conformation-sensitive probe to track local rearrangements along the PIEZO1 blade. Two independent probes, one inserted in an extracellular site distal to the pore and the other in a distant intracellular proximal position, elicit sizable fluorescence signals when the tagged channels activate in response to fluid shear stress of low intensity. Neither cellular indentations nor osmotic swelling of the cell elicit detectable fluorescence signals from either probe, despite the ability of these stimuli to activate the tagged channels. High-intensity flow stimuli are ineffective at eliciting fluorescence signals from either probe. Together, these findings suggest that low-intensity fluid shear stress causes a distinct form of mechanical stress to the cell.
Collapse
Affiliation(s)
- Alper D Ozkan
- Department of Pharmaceutical Microbiology, Bahçeşehir University, Yıldız, Çırağan Cd, 34349 Beşiktaş/İstanbul, Turkey
| | - Tharaka D Wijerathne
- Department of Basic Medical Sciences, Western University of Health Sciences, 309 E. Second St, Pomona, CA 91766, USA
| | - Tina Gettas
- Department of Basic Medical Sciences, Western University of Health Sciences, 309 E. Second St, Pomona, CA 91766, USA
| | - Jérôme J Lacroix
- Department of Basic Medical Sciences, Western University of Health Sciences, 309 E. Second St, Pomona, CA 91766, USA.
| |
Collapse
|
12
|
Parsonage G, Cuthbertson K, Endesh N, Murciano N, Hyman AJ, Revill CH, Povstyan OV, Chuntharpursat‐Bon E, Debant M, Ludlow MJ, Futers TS, Lichtenstein L, Kinsella JA, Bartoli F, Rotordam MG, Becker N, Brüggemann A, Foster R, Beech DJ. Improved PIEZO1 agonism through 4-benzoic acid modification of Yoda1. Br J Pharmacol 2023; 180:2039-2063. [PMID: 36457143 PMCID: PMC10952572 DOI: 10.1111/bph.15996] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 10/03/2022] [Accepted: 11/06/2022] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND AND PURPOSE The protein PIEZO1 forms mechanically activated, calcium-permeable, non-selective cation channels in numerous cell types from several species. Options for pharmacological modulation are limited and so we modified a small-molecule agonist at PIEZO1 channels (Yoda1) to increase the ability to modulate these channels. EXPERIMENTAL APPROACH Medicinal chemistry generated Yoda1 analogues that were tested in intracellular calcium and patch-clamp assays on cultured cells exogenously expressing human or mouse PIEZO1 or mouse PIEZO2. Physicochemical assays and wire myography assays on veins from mice with genetic disruption of PIEZO1. KEY RESULTS A Yoda1 analogue (KC159) containing 4-benzoic acid instead of the pyrazine of Yoda1 and its potassium salt (KC289) have equivalent or improved reliability, efficacy and potency, compared with Yoda1 in functional assays. Tested against overexpressed mouse PIEZO1 in calcium assays, the order of potency (as EC50 values, nM) was KC289, 150 > KC159 280 > Yoda1, 600). These compounds were selective for PIEZO1 over other membrane proteins, and the physicochemical properties were more suited to physiological conditions than those of Yoda1. The vasorelaxant effects were consistent with PIEZO1 agonism. In contrast, substitution with 2-benzoic acid failed to generate a modulator. CONCLUSION AND IMPLICATIONS 4-Benzoic acid modification of Yoda1 improves PIEZO1 agonist activity at PIEZO1 channels. We suggest naming this new modulator Yoda2. It should be a useful tool compound in physiological assays and facilitate efforts to identify a binding site. Such compounds may have therapeutic potential, for example, in diseases linked genetically to PIEZO1 such as lymphatic dysplasia.
Collapse
Affiliation(s)
- Gregory Parsonage
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | | | - Naima Endesh
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Nicoletta Murciano
- Nanion Technologies GmbHMunichGermany
- Theoretical Medicine and BiosciencesSaarland UniversityHomburgGermany
| | - Adam J. Hyman
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | | | - Oleksandr V. Povstyan
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | | | - Marjolaine Debant
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Melanie J. Ludlow
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Timothy Simon Futers
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Laeticia Lichtenstein
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Jacob A. Kinsella
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Fiona Bartoli
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| | - Maria Giustina Rotordam
- Nanion Technologies GmbHMunichGermany
- Theoretical Medicine and BiosciencesSaarland UniversityHomburgGermany
| | | | | | | | - David J. Beech
- Leeds Institute of Cardiovascular and Metabolic Medicine, School of MedicineUniversity of LeedsLeedsUK
| |
Collapse
|
13
|
Mulhall EM, Gharpure A, Lee RM, Dubin AE, Aaron JS, Marshall KL, Spencer KR, Reiche MA, Henderson SC, Chew TL, Patapoutian A. Direct observation of the conformational states of PIEZO1. Nature 2023; 620:1117-1125. [PMID: 37587339 PMCID: PMC10468401 DOI: 10.1038/s41586-023-06427-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 23.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Accepted: 07/11/2023] [Indexed: 08/18/2023]
Abstract
PIEZOs are mechanosensitive ion channels that convert force into chemoelectric signals1,2 and have essential roles in diverse physiological settings3. In vitro studies have proposed that PIEZO channels transduce mechanical force through the deformation of extensive blades of transmembrane domains emanating from a central ion-conducting pore4-8. However, little is known about how these channels interact with their native environment and which molecular movements underlie activation. Here we directly observe the conformational dynamics of the blades of individual PIEZO1 molecules in a cell using nanoscopic fluorescence imaging. Compared with previous structural models of PIEZO1, we show that the blades are significantly expanded at rest by the bending stress exerted by the plasma membrane. The degree of expansion varies dramatically along the length of the blade, where decreased binding strength between subdomains can explain increased flexibility of the distal blade. Using chemical and mechanical modulators of PIEZO1, we show that blade expansion and channel activation are correlated. Our findings begin to uncover how PIEZO1 is activated in a native environment. More generally, as we reliably detect conformational shifts of single nanometres from populations of channels, we expect that this approach will serve as a framework for the structural analysis of membrane proteins through nanoscopic imaging.
Collapse
Affiliation(s)
- Eric M Mulhall
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Anant Gharpure
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Rachel M Lee
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Adrienne E Dubin
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Jesse S Aaron
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Kara L Marshall
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
- Department of Neuroscience, Baylor College of Medicine, Houston, TX, USA
| | - Kathryn R Spencer
- Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA
| | - Michael A Reiche
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Scott C Henderson
- Department of Molecular Medicine, Scripps Research, La Jolla, CA, USA
| | - Teng-Leong Chew
- Advanced Imaging Center, Howard Hughes Medical Institute Janelia Research Campus, Ashburn, VA, USA
| | - Ardem Patapoutian
- Howard Hughes Medical Institute, Department of Neuroscience, Dorris Neuroscience Center, Scripps Research, La Jolla, CA, USA.
| |
Collapse
|
14
|
Yuan W, Zhang X, Fan X. The Role of the Piezo1 Mechanosensitive Channel in Heart Failure. Curr Issues Mol Biol 2023; 45:5830-5848. [PMID: 37504285 PMCID: PMC10378680 DOI: 10.3390/cimb45070369] [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: 06/12/2023] [Revised: 07/02/2023] [Accepted: 07/08/2023] [Indexed: 07/29/2023] Open
Abstract
Mechanotransduction (MT) is inseparable from the pathobiology of heart failure (HF). However, the effects of mechanical forces on HF remain unclear. This review briefly describes how Piezo1 functions in HF-affected cells, including endothelial cells (ECs), cardiac fibroblasts (CFs), cardiomyocytes (CMs), and immune cells. Piezo1 is a mechanosensitive ion channel that has been extensively studied in recent years. Piezo1 responds to different mechanical forces and converts them into intracellular signals. The pathways that modulate the Piezo1 switch have also been briefly described. Experimental drugs that specifically activate Piezo1-like proteins, such as Yoda1, Jedi1, and Jedi2, are available for clinical studies to treat Piezo1-related diseases. The only mechanosensitive ion-channel-specific inhibitor available is GsMTx4, which can turn off Piezo1 by modulating the local membrane tension. Ultrasound waves can modulate Piezo1 switching in vitro with the assistance of microbubbles. This review provides new possible targets for heart failure therapy by exploring the cellular functions of Piezo1 that are involved in the progression of the disease. Modulation of Piezo1 activity may, therefore, effectively delay the progression of heart failure.
Collapse
Affiliation(s)
- Weihua Yuan
- National Clinical Research Center for Child Health, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
| | - Xicheng Zhang
- National Clinical Research Center for Child Health, Department of Cardiac Surgery, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
| | - Xiangming Fan
- National Clinical Research Center for Child Health, Department of Cardiac Surgery, Children's Hospital, Zhejiang University School of Medicine, 3333 Binsheng Rd, Hangzhou 310052, China
| |
Collapse
|
15
|
Pontes B, Mendes FA. Mechanical Properties of Glioblastoma: Perspectives for YAP/TAZ Signaling Pathway and Beyond. Diseases 2023; 11:86. [PMID: 37366874 DOI: 10.3390/diseases11020086] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/06/2023] [Accepted: 06/12/2023] [Indexed: 06/28/2023] Open
Abstract
Glioblastoma is a highly aggressive brain tumor with a poor prognosis. Recent studies have suggested that mechanobiology, the study of how physical forces influence cellular behavior, plays an important role in glioblastoma progression. Several signaling pathways, molecules, and effectors, such as focal adhesions, stretch-activated ion channels, or membrane tension variations, have been studied in this regard. Also investigated are YAP/TAZ, downstream effectors of the Hippo pathway, which is a key regulator of cell proliferation and differentiation. In glioblastoma, YAP/TAZ have been shown to promote tumor growth and invasion by regulating genes involved in cell adhesion, migration, and extracellular matrix remodeling. YAP/TAZ can be activated by mechanical cues such as cell stiffness, matrix rigidity, and cell shape changes, which are all altered in the tumor microenvironment. Furthermore, YAP/TAZ have been shown to crosstalk with other signaling pathways, such as AKT, mTOR, and WNT, which are dysregulated in glioblastoma. Thus, understanding the role of mechanobiology and YAP/TAZ in glioblastoma progression could provide new insights into the development of novel therapeutic strategies. Targeting YAP/TAZ and mechanotransduction pathways in glioblastoma may offer a promising approach to treating this deadly disease.
Collapse
Affiliation(s)
- Bruno Pontes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil
- Centro Nacional de Biologia Estrutural e Bioimagem (CENABIO), Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil
| | - Fabio A Mendes
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro 21941-902, RJ, Brazil
| |
Collapse
|
16
|
Wijerathne TD, Ozkan AD, Lacroix JJ. Microscopic mechanism of PIEZO1 activation by pressure-induced membrane stretch. J Gen Physiol 2023; 155:213842. [PMID: 36715688 PMCID: PMC9930135 DOI: 10.1085/jgp.202213260] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Revised: 12/16/2022] [Accepted: 01/19/2023] [Indexed: 01/31/2023] Open
Abstract
Mechanosensitive PIEZO1 ion channels open in response to membrane stretch. Yet, the underlying microscopic mechanism of this activation remains unknown. To probe this mechanism, we used cell-attached pressure-clamp recordings to measure single channel currents at different steady-state negative pipette pressures, spanning the full range of the channel's pressure sensitivity. Pressure-dependent activation occurs through a sharp reduction of the mean shut duration and through a moderate increase of the mean open duration. Across all tested pressures, the distribution of open and shut dwell times best follows sums of two and three exponential components, respectively. As the magnitude of the pressure stimulus increases, the time constants of most of these exponential components gradually change, in opposite directions for open and shut dwell times, and to a similar extent. In addition, while the relative amplitudes of fast and slow components remain unchanged for open intervals, they fully reverse for shut intervals, further reducing the mean shut duration. Using two-dimensional dwell time analysis, Markov-chain modeling, and simulations, we identified a minimal five-states model which recapitulates essential characteristics of single channel data, including microscopic reversibility, correlations between adjacent open and shut intervals, and asymmetric modulation of dwell times by pressure. This study identifies a microscopic mechanism for the activation of PIEZO1 channels by pressure-induced membrane stretch and deepens our fundamental understanding of mechanotransduction by a vertebrate member of the PIEZO channel family.
Collapse
Affiliation(s)
- Tharaka D Wijerathne
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences , Pomona, CA, USA
| | - Alper D Ozkan
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences , Pomona, CA, USA
| | - Jérôme J Lacroix
- Department of Basic Medical Sciences, College of Osteopathic Medicine of the Pacific, Western University of Health Sciences , Pomona, CA, USA
| |
Collapse
|
17
|
Chuntharpursat-Bon E, Povstyan OV, Ludlow MJ, Carrier DJ, Debant M, Shi J, Gaunt HJ, Bauer CC, Curd A, Simon Futers T, Baxter PD, Peckham M, Muench SP, Adamson A, Humphreys N, Tumova S, Bon RS, Cubbon R, Lichtenstein L, Beech DJ. PIEZO1 and PECAM1 interact at cell-cell junctions and partner in endothelial force sensing. Commun Biol 2023; 6:358. [PMID: 37005489 PMCID: PMC10067937 DOI: 10.1038/s42003-023-04706-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 03/14/2023] [Indexed: 04/04/2023] Open
Abstract
Two prominent concepts for the sensing of shear stress by endothelium are the PIEZO1 channel as a mediator of mechanically activated calcium ion entry and the PECAM1 cell adhesion molecule as the apex of a triad with CDH5 and VGFR2. Here, we investigated if there is a relationship. By inserting a non-disruptive tag in native PIEZO1 of mice, we reveal in situ overlap of PIEZO1 with PECAM1. Through reconstitution and high resolution microscopy studies we show that PECAM1 interacts with PIEZO1 and directs it to cell-cell junctions. PECAM1 extracellular N-terminus is critical in this, but a C-terminal intracellular domain linked to shear stress also contributes. CDH5 similarly drives PIEZO1 to junctions but unlike PECAM1 its interaction with PIEZO1 is dynamic, increasing with shear stress. PIEZO1 does not interact with VGFR2. PIEZO1 is required in Ca2+-dependent formation of adherens junctions and associated cytoskeleton, consistent with it conferring force-dependent Ca2+ entry for junctional remodelling. The data suggest a pool of PIEZO1 at cell junctions, the coming together of PIEZO1 and PECAM1 mechanisms and intimate cooperation of PIEZO1 and adhesion molecules in tailoring junctional structure to mechanical requirement.
Collapse
Affiliation(s)
| | | | | | - David J Carrier
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
- School of Biomedical Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | | | - Jian Shi
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | - Hannah J Gaunt
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | | | - Alistair Curd
- School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - T Simon Futers
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | - Paul D Baxter
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | - Michelle Peckham
- School of Molecular and Cellular Biology, University of Leeds, Leeds, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Stephen P Muench
- School of Biomedical Sciences, University of Leeds, Leeds, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Antony Adamson
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Manchester, M13 9PT, UK
| | - Neil Humphreys
- Faculty of Biology, Medicine and Health, University of Manchester, AV Hill Building, Manchester, M13 9PT, UK
| | - Sarka Tumova
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | - Robin S Bon
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK
| | - Richard Cubbon
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK
| | | | - David J Beech
- School of Medicine, University of Leeds, Leeds, LS2 9JT, UK.
| |
Collapse
|
18
|
Jiang W, Lacroix J, Luo YL. Importance of molecular dynamics equilibrium protocol on protein-lipid interaction near channel pore. BIOPHYSICAL REPORTS 2022; 2:100080. [PMID: 36425669 PMCID: PMC9680783 DOI: 10.1016/j.bpr.2022.100080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
Multiscale molecular dynamics simulations using Martini coarse-grained (CG) and all-atom (AA) force fields are commonly used in membrane protein studies. In particular, reverse mapping an equilibrated CG model to an AA model offers an efficient way for preparing large membrane protein systems with complex protein shapes and lipid compositions. Here, we report that this hybrid CG-equilibrium-AA-production protocol may artificially increase lipid density and decrease hydration in ion channel pores walled with transmembrane gaps. To understand the origin of this conundrum, we conducted replicas of CG, AA, and CG reverse-mapped AA simulations of the pore domain of the mechanosensitive Piezo1 channel in a nonconducting conformation. Lipid/water density analysis and free energy calculations reveal that the lack of initial pore hydration allows excessive lipids to enter the upper pore lumen through gaps between pore helices during CG simulation. Due to the mismatch between CG and AA lipid kinetics, these pore lipids remain trapped in the subsequent AA simulations, despite unfavorable binding free energy. We tested several CG equilibrium protocols and found that a protocol restraining the whole lipid produces pore hydration consistent with AA results, thus eliminating this artifact for further studies of lipid gating and protein-lipid interactions.
Collapse
Affiliation(s)
- Wenjuan Jiang
- College of Pharmacy, Western University of Health Sciences, Pomona, California
| | - Jerome Lacroix
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, California
| | - Yun Lyna Luo
- College of Pharmacy, Western University of Health Sciences, Pomona, California
| |
Collapse
|
19
|
Yang S, Miao X, Arnold S, Li B, Ly AT, Wang H, Wang M, Guo X, Pathak MM, Zhao W, Cox CD, Shi Z. Membrane curvature governs the distribution of Piezo1 in live cells. Nat Commun 2022; 13:7467. [PMID: 36463216 PMCID: PMC9719557 DOI: 10.1038/s41467-022-35034-6] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 11/16/2022] [Indexed: 12/05/2022] Open
Abstract
Piezo1 is a bona fide mechanosensitive ion channel ubiquitously expressed in mammalian cells. The distribution of Piezo1 within a cell is essential for various biological processes including cytokinesis, cell migration, and wound healing. However, the underlying principles that guide the subcellular distribution of Piezo1 remain largely unexplored. Here, we demonstrate that membrane curvature serves as a key regulator of the spatial distribution of Piezo1 in the plasma membrane of living cells. Piezo1 depletes from highly curved membrane protrusions such as filopodia and enriches to nanoscale membrane invaginations. Quantification of the curvature-dependent sorting of Piezo1 directly reveals the in situ nano-geometry of the Piezo1-membrane complex. Piezo1 density on filopodia increases upon activation, independent of calcium, suggesting flattening of the channel upon opening. Consequently, the expression of Piezo1 inhibits filopodia formation, an effect that diminishes with channel activation.
Collapse
Affiliation(s)
- Shilong Yang
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Xinwen Miao
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 637457, Singapore, Singapore
| | - Steven Arnold
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ, 08854, USA
| | - Boxuan Li
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Alan T Ly
- Department of Physiology & Biophysics, UC Irvine, Irvine, CA, 92697, USA
- Sue and Bill Gross Stem Cell Research Center, UC Irvine, Irvine, CA, 92697, USA
| | - Huan Wang
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA
| | - Matthew Wang
- Department of Physics, Rutgers University, Piscataway, NJ, 08854, USA
| | - Xiangfu Guo
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 637457, Singapore, Singapore
| | - Medha M Pathak
- Department of Physiology & Biophysics, UC Irvine, Irvine, CA, 92697, USA
- Sue and Bill Gross Stem Cell Research Center, UC Irvine, Irvine, CA, 92697, USA
| | - Wenting Zhao
- School of Chemistry, Chemical Engineering, and Biotechnology, Nanyang Technological University, 637457, Singapore, Singapore
| | - Charles D Cox
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, NSW, Australia
| | - Zheng Shi
- Department of Chemistry and Chemical Biology, Rutgers University, Piscataway, NJ, 08854, USA.
- Cancer Pharmacology Research Program, Cancer Institute of New Jersey, Rutgers University, New Brunswick, NJ, 08901, USA.
| |
Collapse
|
20
|
Xu H, He Y, Hong T, Bi C, Li J, Xia M. Piezo1 in vascular remodeling of atherosclerosis and pulmonary arterial hypertension: A potential therapeutic target. Front Cardiovasc Med 2022; 9:1021540. [PMID: 36247424 PMCID: PMC9557227 DOI: 10.3389/fcvm.2022.1021540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 09/12/2022] [Indexed: 11/13/2022] Open
Abstract
Vascular remodeling (VR) is a structural and functional change of blood vessels to adapt to the changes of internal and external environment. It is one of the common pathological features of many vascular proliferative diseases. The process of VR is mainly manifested in the changes of vascular wall structure and function, including intimal hyperplasia, thickening or thinning of media, fibrosis of adventitia, etc. These changes are also the pathological basis of aging and various cardiovascular diseases. Mechanical force is the basis of cardiovascular biomechanics, and the newly discovered mechanical sensitive ion channel Piezo1 is widely distributed in the whole cardiovascular system. Studies have confirmed that Piezo1, a mechanically sensitive ion channel, plays an important role in cardiovascular remodeling diseases. This article reviews the molecular mechanism of Piezo1 in atherosclerosis, hypertension and pulmonary hypertension, in order to provide a theoretical basis for the further study of vascular remodeling.
Collapse
Affiliation(s)
- Han Xu
- Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Yu He
- Cardiovascular Surgery Department, The First Affiliated Hospital of Xi'an Jiaotong University, Xian, China
| | - Tianying Hong
- Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Cong Bi
- Department of Vascular Surgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, China
| | - Jing Li
- Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
- Jing Li
| | - Mingfeng Xia
- Innovation Research Institute of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, China
- *Correspondence: Mingfeng Xia
| |
Collapse
|
21
|
Martinac B, Kung C. The force-from-lipid principle and its origin, a ‘ what is true for E. coli is true for the elephant’ refrain. J Neurogenet 2022; 36:44-54. [DOI: 10.1080/01677063.2022.2097674] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Boris Martinac
- Molecular Cardiology and Biophysics Division, Victor Chang Cardiac Research Institute, Sydney, Australia
- School of Clinical Medicine, UNSW Medicine & Health, St Vincent's Healthcare Clinical Campus, Faculty of Medicine and Health, University of New South Wales, Sydney, Australia
| | - Ching Kung
- Laboratory of Molecular Biology and the Department of Genetics, University of Wisconsin–Madison, Madison, WI, USA
| |
Collapse
|
22
|
Wijerathne TD, Ozkan AD, Lacroix JJ. Yoda1's energetic footprint on Piezo1 channels and its modulation by voltage and temperature. Proc Natl Acad Sci U S A 2022; 119:e2202269119. [PMID: 35858335 PMCID: PMC9303978 DOI: 10.1073/pnas.2202269119] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 05/31/2022] [Indexed: 01/13/2023] Open
Abstract
Piezo1 channels are essential mechanically activated ion channels in vertebrates. Their selective activation by the synthetic chemical activator Yoda1 opened new avenues to probe their gating mechanisms and develop novel pharmaceuticals. Yet, the nature and extent of Piezo1 functions modulated by this small molecule remain unclear. Here we close this gap by conducting a comprehensive biophysical investigation of the effects of Yoda1 on mouse Piezo1 in mammalian cells. Using calcium imaging, we first show that cysteine bridges known to inhibit mechanically evoked Piezo1 currents also inhibit activation by Yoda1, suggesting Yoda1 acts by energetically modulating mechanosensory domains. The presence of Yoda1 alters single-channel dwell times and macroscopic kinetics consistent with a dual and reciprocal energetic modulation of open and shut states. Critically, we further discovered that the electrophysiological effects of Yoda1 depend on membrane potential and temperature, two other Piezo1 modulators. This work illuminates a complex interplay between physical and chemical modulators of Piezo1 channels.
Collapse
Affiliation(s)
- Tharaka D. Wijerathne
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766
| | - Alper D. Ozkan
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766
| | - Jérôme J. Lacroix
- Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766
| |
Collapse
|
23
|
Young M, Lewis AH, Grandl J. Physics of mechanotransduction by Piezo ion channels. J Gen Physiol 2022; 154:213231. [PMID: 35593732 PMCID: PMC9127981 DOI: 10.1085/jgp.202113044] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/28/2022] [Accepted: 04/29/2022] [Indexed: 12/26/2022] Open
Abstract
Piezo ion channels are sensors of mechanical forces and mediate a wide range of physiological mechanotransduction processes. More than a decade of intense research has elucidated much of the structural and mechanistic principles underlying Piezo gating and its roles in physiology, although wide gaps of knowledge continue to exist. Here, we review the forces and energies involved in mechanical activation of Piezo ion channels and their functional modulation by other chemical and physical stimuli including lipids, voltage, and temperature. We compare the three predominant mechanisms likely to explain Piezo activation—the force-from-lipids mechanism, the tether model, and the membrane footprint theory. Additional sections shine light on how Piezo ion channels may affect each other through spatial clustering and functional cooperativity, and how substantial functional heterogeneity of Piezo ion channels arises as a byproduct of the precise physical environment each channel experiences. Finally, our review concludes by pointing out major research questions and technological limitations that future research can address.
Collapse
Affiliation(s)
- Michael Young
- Department of Neurobiology, Duke University Medical Center, Durham, NC
| | - Amanda H Lewis
- Department of Neurobiology, Duke University Medical Center, Durham, NC
| | - Jörg Grandl
- Department of Neurobiology, Duke University Medical Center, Durham, NC
| |
Collapse
|
24
|
The many faces of membrane tension: Challenges across systems and scales. BIOCHIMICA ET BIOPHYSICA ACTA. BIOMEMBRANES 2022; 1864:183897. [PMID: 35231438 DOI: 10.1016/j.bbamem.2022.183897] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Revised: 02/09/2022] [Accepted: 02/16/2022] [Indexed: 01/27/2023]
Abstract
Our understanding of the role of membrane tension in the field of membrane biophysics is rapidly evolving from a passive construct to an active player in a variety of cellular phenomena. Membrane tension has been shown to be a key regulator of many cellular processes ranging including trafficking, ion channel activation, and the invasion of red blood cells by malaria parasites. Recent experimental advances in cells, including the development of a fluorescent tension reporter, have shown that membrane tension is heterogeneous. In this mini-review, I summarize the recent advances in membrane tension measurements and discuss the contributions from different cellular constituents such as the cortical cytoskeleton. Then, I will explore how these different complexities can be considered in biophysical models of different scales. Finally, I will elaborate on the need for iterations between models and experiments as technologies in both fields advance to enable us to obtain critical insights into the physiological role of membrane tension as a critical component of mechanotransduction.
Collapse
|
25
|
Structure deformation and curvature sensing of PIEZO1 in lipid membranes. Nature 2022; 604:377-383. [PMID: 35388220 DOI: 10.1038/s41586-022-04574-8] [Citation(s) in RCA: 77] [Impact Index Per Article: 38.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 02/23/2022] [Indexed: 12/16/2022]
Abstract
PIEZO channels respond to piconewton-scale forces to mediate critical physiological and pathophysiological processes1-5. Detergent-solubilized PIEZO channels form bowl-shaped trimers comprising a central ion-conducting pore with an extracellular cap and three curved and non-planar blades with intracellular beams6-10, which may undergo force-induced deformation within lipid membranes11. However, the structures and mechanisms underlying the gating dynamics of PIEZO channels in lipid membranes remain unresolved. Here we determine the curved and flattened structures of PIEZO1 reconstituted in liposome vesicles, directly visualizing the substantial deformability of the PIEZO1-lipid bilayer system and an in-plane areal expansion of approximately 300 nm2 in the flattened structure. The curved structure of PIEZO1 resembles the structure determined from detergent micelles, but has numerous bound phospholipids. By contrast, the flattened structure exhibits membrane tension-induced flattening of the blade, bending of the beam and detaching and rotating of the cap, which could collectively lead to gating of the ion-conducting pathway. On the basis of the measured in-plane membrane area expansion and stiffness constant of PIEZO1 (ref. 11), we calculate a half maximal activation tension of about 1.9 pN nm-1, matching experimentally measured values. Thus, our studies provide a fundamental understanding of how the notable deformability and structural rearrangement of PIEZO1 achieve exquisite mechanosensitivity and unique curvature-based gating in lipid membranes.
Collapse
|
26
|
Shinge SAU, Zhang D, Din AU, Yu F, Nie Y. Emerging Piezo1 signaling in inflammation and atherosclerosis; a potential therapeutic target. Int J Biol Sci 2022; 18:923-941. [PMID: 35173527 PMCID: PMC8771847 DOI: 10.7150/ijbs.63819] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Accepted: 11/08/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose of Review: Atherosclerosis is the principal cause of cardiovascular diseases (CVDs) which are the major cause of death worldwide. Mechanical force plays an essential role in cardiovascular health and disease. To bring the awareness of mechanosensitive Piezo1 role in atherosclerosis and its therapeutic potentials we review recent literature to highlight its involvement in various mechanisms of the disease. Recent Findings: Recent studies reported Piezo1 channel as a sensor, and transducer of various mechanical forces into biochemical signals, which affect various cellular activities such as proliferation, migration, apoptosis and vascular remodeling including immune/inflammatory mechanisms fundamental phenomenon in atherogenesis. Summary: Numerous evidences suggest Piezo1 as a player in different mechanisms of cell biology, including immune/inflammatory and other cellular mechanisms correlated with atherosclerosis. This review discusses mechanistic insight about this matter and highlights the drugability and therapeutic potentials consistent with emerging functions Piezo1 in various mechanisms of atherosclerosis. Based on the recent works, we suggest Piezo1 as potential therapeutic target and a valid candidate for future research. Therefore, a deeper exploration of Piezo1 biology and translation towards the clinic will be a novel strategy for treating atherosclerosis and other CVDs.
Collapse
Affiliation(s)
- Shafiu A. Umar Shinge
- Cardiovascular Surgery Department, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan PRC
| | - Daifang Zhang
- Cardiovascular Surgery Department, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan PRC
- Clinical Research Center, Southwest Medical University, Luzhou, Sichuan PRC
| | - Ahmad Ud Din
- Drug Discovery Research Center, Southwest Medical University, Luzhou, Sichuan PRC
| | - FengXu Yu
- Cardiovascular Surgery Department, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan PRC
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan PRC
| | - YongMei Nie
- Cardiovascular Surgery Department, Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan PRC
- Collaborative Innovation Center for Prevention and Treatment of Cardiovascular Disease of Sichuan Province, Southwest Medical University, Luzhou, Sichuan PRC
| |
Collapse
|
27
|
Lin Y, Buyan A, Corry B. Computational studies of Piezo1 yield insights into key lipid–protein interactions, channel activation, and agonist binding. Biophys Rev 2021; 14:209-219. [DOI: 10.1007/s12551-021-00847-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 09/20/2021] [Indexed: 12/21/2022] Open
|