1
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Murata D, Roy S, Lutsenko S, Iijima M, Sesaki H. Slc25a3-dependent copper transport controls flickering-induced Opa1 processing for mitochondrial safeguard. Dev Cell 2024; 59:2578-2592.e7. [PMID: 38986607 PMCID: PMC11461135 DOI: 10.1016/j.devcel.2024.06.008] [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: 12/12/2022] [Revised: 04/18/2024] [Accepted: 06/17/2024] [Indexed: 07/12/2024]
Abstract
Following the Goldilocks principle, mitochondria size must be "just right." Mitochondria balance division and fusion to avoid becoming too big or too small. Defects in this balance produce dysfunctional mitochondria in human diseases. Mitochondrial safeguard (MitoSafe) is a defense mechanism that protects mitochondria against extreme enlarging by suppressing fusion in mammalian cells. In MitoSafe, hyperfused mitochondria elicit flickering-short pulses of mitochondrial depolarization. Flickering activates an inner membrane protease, Oma1, which in turn proteolytically inactivates a mitochondrial fusion protein, Opa1. The mechanisms underlying flickering are unknown. Using a live-imaging screen, we identified Slc25a3 (a mitochondrial carrier transporting phosphate and copper) as necessary for flickering and Opa1 cleavage. Remarkably, copper, but not phosphate, is critical for flickering. Furthermore, we found that two copper-containing mitochondrial enzymes, superoxide dismutase 1 and cytochrome c oxidase, regulate flickering. Our data identify an unforeseen mechanism linking copper, redox homeostasis, and membrane flickering in mitochondrial defense against deleterious fusion.
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Affiliation(s)
- Daisuke Murata
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Shubhrajit Roy
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Svetlana Lutsenko
- Department of Physiology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Miho Iijima
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
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2
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Versini R, Baaden M, Cavellini L, Cohen MM, Taly A, Fuchs PFJ. Lys716 in the transmembrane domain of yeast mitofusin Fzo1 modulates anchoring and fusion. Structure 2024:S0969-2126(24)00334-4. [PMID: 39299234 DOI: 10.1016/j.str.2024.08.017] [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: 12/22/2023] [Revised: 05/06/2024] [Accepted: 08/23/2024] [Indexed: 09/22/2024]
Abstract
Outer mitochondrial membrane fusion, a vital cellular process, is mediated by mitofusins. However, the underlying molecular mechanism remains elusive. We have performed extensive multiscale molecular dynamics simulations to predict a model of the transmembrane (TM) domain of the yeast mitofusin Fzo1. Coarse-grained simulations of the two TM domain helices, TM1 and TM2, reveal a stable interface, which is controlled by the charge status of residue Lys716. Atomistic replica-exchange simulations further tune our model, which is confirmed by a remarkable agreement with an independent AlphaFold2 (AF2) prediction of Fzo1 in complex with its fusion partner Ugo1. Furthermore, the presence of the TM domain destabilizes the membrane, even more if Lys716 is charged, which can be an asset for initiating fusion. The functional role of Lys716 was confirmed with yeast experiments, which show that mutating Lys716 to a hydrophobic residue prevents mitochondrial fusion.
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Affiliation(s)
- Raphaëlle Versini
- Laboratoire de Biochimie Théorique, CNRS, Université Paris Cité, 75005 Paris, France; Laboratoire des Biomolécules, LBM, Sorbonne Université, École normale supérieure, PSL University, CNRS, 75005 Paris, France
| | - Marc Baaden
- Laboratoire de Biochimie Théorique, CNRS, Université Paris Cité, 75005 Paris, France
| | - Laetitia Cavellini
- Laboratoire de Biologie Cellulaire et Moléculaire des Eucaryotes, Institut de Biologie Physico-Chimique, UMR 8226, CNRS, Sorbonne Université, Paris, France
| | - Mickaël M Cohen
- Laboratoire de Biologie Cellulaire et Moléculaire des Eucaryotes, Institut de Biologie Physico-Chimique, UMR 8226, CNRS, Sorbonne Université, Paris, France
| | - Antoine Taly
- Laboratoire de Biochimie Théorique, CNRS, Université Paris Cité, 75005 Paris, France.
| | - Patrick F J Fuchs
- Laboratoire des Biomolécules, LBM, Sorbonne Université, École normale supérieure, PSL University, CNRS, 75005 Paris, France; Université Paris Cité, 75006 Paris, France.
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3
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Sun F, Fang M, Zhang H, Song Q, Li S, Li Y, Jiang S, Yang L. Drp1: Focus on Diseases Triggered by the Mitochondrial Pathway. Cell Biochem Biophys 2024; 82:435-455. [PMID: 38438751 DOI: 10.1007/s12013-024-01245-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2024] [Indexed: 03/06/2024]
Abstract
Drp1 (Dynamin-Related Protein 1) is a cytoplasmic GTPase protein encoded by the DNM1L gene that influences mitochondrial dynamics by mediating mitochondrial fission processes. Drp1 has been demonstrated to play an important role in a variety of life activities such as cell survival, proliferation, migration, and death. Drp1 has been shown to play different physiological roles under different physiological conditions, such as normal and inflammation. Recently studies have revealed that Drp1 plays a critical role in the occurrence, development, and aggravation of a series of diseases, thereby it serves as a potential therapeutic target for them. In this paper, we review the structure and biological properties of Drp1, summarize the biological processes that occur in the inflammatory response to Drp1, discuss its role in various cancers triggered by the mitochondrial pathway and investigate effective methods for targeting Drp1 in cancer treatment. We also synthesized the phenomena of Drp1 involving in the triggering of other diseases. The results discussed herein contribute to our deeper understanding of mitochondrial kinetic pathway-induced diseases and their therapeutic applications. It is critical for advancing the understanding of the mechanisms of Drp1-induced mitochondrial diseases and preventive therapies.
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Affiliation(s)
- Fulin Sun
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
- Health Science Center, Qingdao University, Qingdao, China
| | - Min Fang
- Department of Gynaecology, Qingdao Women and Children's Hospital, Qingdao, 266021, Shandong, China
| | - Huhu Zhang
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
| | - Qinghang Song
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
- Health Science Center, Qingdao University, Qingdao, China
| | - Shuang Li
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
| | - Ya Li
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
| | - Shuyao Jiang
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China
- Health Science Center, Qingdao University, Qingdao, China
| | - Lina Yang
- Department of Genetics and Cell Biology, Basic Medical College, Qingdao University, Qingdao, China.
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4
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Jung S, Woo J, Park E. Talk to your neighbors in an emergency: Stromule-mediated chloroplast-nucleus communication in plant immunity. CURRENT OPINION IN PLANT BIOLOGY 2024; 79:102529. [PMID: 38604000 DOI: 10.1016/j.pbi.2024.102529] [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: 11/21/2022] [Revised: 03/08/2024] [Accepted: 03/19/2024] [Indexed: 04/13/2024]
Abstract
Hypersensitive response-programmed cell death (HR-PCD) is a response mounted by plants to defend themselves against pathogens. Communication between the chloroplast and the nucleus is critical for the progression of HR-PCD. Tubular protrusions of chloroplasts, known as stromules, are tightly associated with the HR-PCD progression. There is emerging evidence that signaling molecules originating from chloroplasts are transferred to the nucleus through stromules. The translocation of signaling molecules from the chloroplast to the nucleus might trigger defense responses, including transcriptional reprogramming. In this review, we discuss the possible functions of stromules in the rapid transfer of signaling molecules in the chloroplast-nucleus communication.
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Affiliation(s)
- Seungmee Jung
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
| | - Jongchan Woo
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA
| | - Eunsook Park
- Department of Molecular Biology, University of Wyoming, Laramie, WY 82071, USA.
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5
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He X, Wang L, Tsang HY, Liu X, Yang X, Pu S, Guo Z, Yang C, Wu Q, Zhou Z, Cen X, Zhao H. GTPBP8 modulates mitochondrial fission through a Drp1-dependent process. J Cell Sci 2024; 137:jcs261612. [PMID: 38587461 PMCID: PMC11112121 DOI: 10.1242/jcs.261612] [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: 09/07/2023] [Accepted: 03/26/2024] [Indexed: 04/09/2024] Open
Abstract
Mitochondrial fission is a tightly regulated process involving multiple proteins and cell signaling. Despite extensive studies on mitochondrial fission factors, our understanding of the regulatory mechanisms remains limited. This study shows the critical role of a mitochondrial GTPase, GTPBP8, in orchestrating mitochondrial fission in mammalian cells. Depletion of GTPBP8 resulted in drastic elongation and interconnectedness of mitochondria. Conversely, overexpression of GTPBP8 shifted mitochondrial morphology from tubular to fragmented. Notably, the induced mitochondrial fragmentation from GTPBP8 overexpression was inhibited in cells either depleted of the mitochondrial fission protein Drp1 (also known as DNM1L) or carrying mutated forms of Drp1. Importantly, downregulation of GTPBP8 caused an increase in oxidative stress, modulating cell signaling involved in the increased phosphorylation of Drp1 at Ser637. This phosphorylation hindered the recruitment of Drp1 to mitochondria, leading to mitochondrial fission defects. By contrast, GTPBP8 overexpression triggered enhanced recruitment and assembly of Drp1 at mitochondria. In summary, our study illuminates the cellular function of GTPBP8 as a pivotal modulator of the mitochondrial division apparatus, inherently reliant on its influence on Drp1.
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Affiliation(s)
- Xiumei He
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Mental Health Center and National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Liang Wang
- Mental Health Center and National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Hoi Ying Tsang
- Faculty of Biological and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
| | - Xiaonan Liu
- Department of Physiology, Faculty of Medical Sciences in Katowice, Medical University of Silesia in Katowice, Katowice 40752, Poland
| | - Xiaofeng Yang
- Mental Health Center and National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Shiming Pu
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Ziqi Guo
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Cheng Yang
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Qiong Wu
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Zuping Zhou
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
| | - Xiaobo Cen
- Mental Health Center and National Chengdu Center for Safety Evaluation of Drugs, State Key Laboratory of Biotherapy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Hongxia Zhao
- School of Life Sciences, Guangxi Normal University, Guilin 541004, China
- Guangxi Universities Key Laboratory of Stem Cell and Biopharmaceutical Technology, Guangxi Normal University, Guilin 541004, China
- Faculty of Biological and Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
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6
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Alsayyah C, Singh MK, Morcillo-Parra MA, Cavellini L, Shai N, Schmitt C, Schuldiner M, Zalckvar E, Mallet A, Belgareh-Touzé N, Zimmer C, Cohen MM. Mitofusin-mediated contacts between mitochondria and peroxisomes regulate mitochondrial fusion. PLoS Biol 2024; 22:e3002602. [PMID: 38669296 PMCID: PMC11078399 DOI: 10.1371/journal.pbio.3002602] [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: 02/06/2024] [Revised: 05/08/2024] [Accepted: 03/26/2024] [Indexed: 04/28/2024] Open
Abstract
Mitofusins are large GTPases that trigger fusion of mitochondrial outer membranes. Similarly to the human mitofusin Mfn2, which also tethers mitochondria to the endoplasmic reticulum (ER), the yeast mitofusin Fzo1 stimulates contacts between Peroxisomes and Mitochondria when overexpressed. Yet, the physiological significance and function of these "PerMit" contacts remain unknown. Here, we demonstrate that Fzo1 naturally localizes to peroxisomes and promotes PerMit contacts in physiological conditions. These contacts are regulated through co-modulation of Fzo1 levels by the ubiquitin-proteasome system (UPS) and by the desaturation status of fatty acids (FAs). Contacts decrease under low FA desaturation but reach a maximum during high FA desaturation. High-throughput genetic screening combined with high-resolution cellular imaging reveal that Fzo1-mediated PerMit contacts favor the transit of peroxisomal citrate into mitochondria. In turn, citrate enters the TCA cycle to stimulate the mitochondrial membrane potential and maintain efficient mitochondrial fusion upon high FA desaturation. These findings thus unravel a mechanism by which inter-organelle contacts safeguard mitochondrial fusion.
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Affiliation(s)
- Cynthia Alsayyah
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
| | - Manish K. Singh
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
- Institut Pasteur, Université Paris Cité, Imaging and Modeling Unit, F-75015 Paris, France
| | - Maria Angeles Morcillo-Parra
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
| | - Laetitia Cavellini
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
| | - Nadav Shai
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Christine Schmitt
- Ultrastructural BioImaging Core Facility, C2RT, Institut Pasteur, Université Paris Cité, Paris, France
| | - Maya Schuldiner
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Einat Zalckvar
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
| | - Adeline Mallet
- Ultrastructural BioImaging Core Facility, C2RT, Institut Pasteur, Université Paris Cité, Paris, France
| | - Naïma Belgareh-Touzé
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
| | - Christophe Zimmer
- Institut Pasteur, Université Paris Cité, Imaging and Modeling Unit, F-75015 Paris, France
- Rudolf Virchow Center for Integrative and Translational Bioimaging, University of Würzburg, Würzburg, Germany
| | - Mickaël M. Cohen
- Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Paris, France
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7
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Pérez-Jover I, Rochon K, Hu D, Mahajan M, Madan Mohan P, Santos-Pérez I, Ormaetxea Gisasola J, Martinez Galvez JM, Agirre J, Qi X, Mears JA, Shnyrova AV, Ramachandran R. Allosteric control of dynamin-related protein 1 through a disordered C-terminal Short Linear Motif. Nat Commun 2024; 15:52. [PMID: 38168038 PMCID: PMC10761769 DOI: 10.1038/s41467-023-44413-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Accepted: 12/07/2023] [Indexed: 01/05/2024] Open
Abstract
The mechanochemical GTPase dynamin-related protein 1 (Drp1) catalyzes mitochondrial and peroxisomal fission, but the regulatory mechanisms remain ambiguous. Here we find that a conserved, intrinsically disordered, six-residue Short Linear Motif at the extreme Drp1 C-terminus, named CT-SLiM, constitutes a critical allosteric site that controls Drp1 structure and function in vitro and in vivo. Extension of the CT-SLiM by non-native residues, or its interaction with the protein partner GIPC-1, constrains Drp1 subunit conformational dynamics, alters self-assembly properties, and limits cooperative GTP hydrolysis, surprisingly leading to the fission of model membranes in vitro. In vivo, the involvement of the native CT-SLiM is critical for productive mitochondrial and peroxisomal fission, as both deletion and non-native extension of the CT-SLiM severely impair their progression. Thus, contrary to prevailing models, Drp1-catalyzed membrane fission relies on allosteric communication mediated by the CT-SLiM, deceleration of GTPase activity, and coupled changes in subunit architecture and assembly-disassembly dynamics.
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Affiliation(s)
- Isabel Pérez-Jover
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
- Instituto Biofisika, CSIC, UPV/EHU, 48940, Leioa, Spain
| | - Kristy Rochon
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Di Hu
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Mukesh Mahajan
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Pooja Madan Mohan
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Isaac Santos-Pérez
- Electron Microscopy and Crystallography Center for Cooperative Research in Biosciences (CIC bioGUNE), Bizkaia Science and Technology, Park Bld 800, 48160-Derio, Bizkaia, Spain
| | - Julene Ormaetxea Gisasola
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
- Instituto Biofisika, CSIC, UPV/EHU, 48940, Leioa, Spain
| | - Juan Manuel Martinez Galvez
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain
- Instituto Biofisika, CSIC, UPV/EHU, 48940, Leioa, Spain
| | - Jon Agirre
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, YO10 5DD, York, UK
| | - Xin Qi
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Jason A Mears
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Anna V Shnyrova
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940, Leioa, Spain.
- Instituto Biofisika, CSIC, UPV/EHU, 48940, Leioa, Spain.
| | - Rajesh Ramachandran
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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8
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Su YA, Chiu HY, Chang YC, Sung CJ, Chen CW, Tei R, Huang XR, Hsu SC, Lin SS, Wang HC, Lin YC, Hsu JC, Bauer H, Feng Y, Baskin JM, Chang ZF, Liu YW. NME3 binds to phosphatidic acid and mediates PLD6-induced mitochondrial tethering. J Cell Biol 2023; 222:e202301091. [PMID: 37584589 PMCID: PMC10432850 DOI: 10.1083/jcb.202301091] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 06/10/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
Mitochondria are dynamic organelles regulated by fission and fusion processes. The fusion of membranes requires elaborative coordination of proteins and lipids and is particularly crucial for the function and quality control of mitochondria. Phosphatidic acid (PA) on the mitochondrial outer membrane generated by PLD6 facilitates the fusion of mitochondria. However, how PA promotes mitochondrial fusion remains unclear. Here, we show that a mitochondrial outer membrane protein, NME3, is required for PLD6-induced mitochondrial tethering or clustering. NME3 is enriched at the contact interface of two closely positioned mitochondria depending on PLD6, and NME3 binds directly to PA-exposed lipid packing defects via its N-terminal amphipathic helix. The PA binding function and hexamerization confer NME3 mitochondrial tethering activity. Importantly, nutrient starvation enhances the enrichment efficiency of NME3 at the mitochondrial contact interface, and the tethering ability of NME3 contributes to fusion efficiency. Together, our findings demonstrate NME3 as a tethering protein promoting selective fusion between PLD6-remodeled mitochondria for quality control.
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Affiliation(s)
- You-An Su
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsin-Yi Chiu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Yu-Chen Chang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chieh-Ju Sung
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Chih-Wei Chen
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Reika Tei
- Department of Chemistry and Chemical Biology and Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Xuang-Rong Huang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shao-Chun Hsu
- Imaging Core, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shan-Shan Lin
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Hsien-Chu Wang
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
| | - Yu-Chun Lin
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
- Department of Medical Science, National Tsing Hua University, Hsinchu, Taiwan
| | - Jui-Cheng Hsu
- Institute of Molecular Medicine, National Tsing Hua University, Hsinchu, Taiwan
| | - Hermann Bauer
- Department of Developmental Genetics, Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Yuxi Feng
- Department of Experimental Pharmacology, Medical Faculty Mannheim, Heidelberg University, Heidelberg, Germany
| | - Jeremy M. Baskin
- Department of Chemistry and Chemical Biology and Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY, USA
| | - Zee-Fen Chang
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Ya-Wen Liu
- Institute of Molecular Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
- Center of Precision Medicine, College of Medicine, National Taiwan University, Taipei, Taiwan
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9
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Liu C, Mentzelopoulou A, Papagavriil F, Ramachandran P, Perraki A, Claus L, Barg S, Dörmann P, Jaillais Y, Johnen P, Russinova E, Gizeli E, Schaaf G, Moschou PN. SEC14-like condensate phase transitions at plasma membranes regulate root growth in Arabidopsis. PLoS Biol 2023; 21:e3002305. [PMID: 37721949 PMCID: PMC10538751 DOI: 10.1371/journal.pbio.3002305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2022] [Revised: 09/28/2023] [Accepted: 08/20/2023] [Indexed: 09/20/2023] Open
Abstract
Protein function can be modulated by phase transitions in their material properties, which can range from liquid- to solid-like; yet, the mechanisms that drive these transitions and whether they are important for physiology are still unknown. In the model plant Arabidopsis, we show that developmental robustness is reinforced by phase transitions of the plasma membrane-bound lipid-binding protein SEC14-like. Using imaging, genetics, and in vitro reconstitution experiments, we show that SEC14-like undergoes liquid-like phase separation in the root stem cells. Outside the stem cell niche, SEC14-like associates with the caspase-like protease separase and conserved microtubule motors at unique polar plasma membrane interfaces. In these interfaces, SEC14-like undergoes processing by separase, which promotes its liquid-to-solid transition. This transition is important for root development, as lines expressing an uncleavable SEC14-like variant or mutants of separase and associated microtubule motors show similar developmental phenotypes. Furthermore, the processed and solidified but not the liquid form of SEC14-like interacts with and regulates the polarity of the auxin efflux carrier PINFORMED2. This work demonstrates that robust development can involve liquid-to-solid transitions mediated by proteolysis at unique plasma membrane interfaces.
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Affiliation(s)
- Chen Liu
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
| | - Andriani Mentzelopoulou
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Fotini Papagavriil
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Prashanth Ramachandran
- Department of Organismal Biology, Physiological Botany, Linnean Centre for Plant Biology, Uppsala University, Uppsala, Sweden
| | - Artemis Perraki
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Lucas Claus
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, Ghent, Belgium
| | - Sebastian Barg
- Department of Medical Cell Biology, Uppsala University, Uppsala, Sweden
| | - Peter Dörmann
- Institute of Molecular Physiology and Biotechnology of Plants, University of Bonn, Bonn, Germany
| | - Yvon Jaillais
- Laboratoire Reproduction et Développement des Plantes, ENS de Lyon, Université Claude Bernard Lyon 1, CNRS, INRAE, Lyon, France
| | - Philipp Johnen
- Department of Plant Nutrition, Institute of Crop Science and Resource Conservation, University of Bonn, Bonn, Germany
| | - Eugenia Russinova
- Department of Plant Biotechnology and Bioinformatics, Ghent University, Ghent, Belgium
- Center for Plant Systems Biology, Ghent, Belgium
| | - Electra Gizeli
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
| | - Gabriel Schaaf
- Department of Plant Nutrition, Institute of Crop Science and Resource Conservation, University of Bonn, Bonn, Germany
| | - Panagiotis Nikolaou Moschou
- Department of Biology, University of Crete, Heraklion, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
- Department of Plant Biology, Uppsala BioCenter, Swedish University of Agricultural Sciences and Linnean Center for Plant Biology, Uppsala, Sweden
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10
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Pérez-Jover I, Rochon K, Hu D, Mohan PM, Santos-Perez I, Gisasola JO, Galvez JMM, Agirre J, Qi X, Mears JA, Shnyrova AV, Ramachandran R. Allosteric control of dynamin-related protein 1-catalyzed mitochondrial fission through a conserved disordered C-terminal Short Linear Motif. RESEARCH SQUARE 2023:rs.3.rs-3161608. [PMID: 37503116 PMCID: PMC10371074 DOI: 10.21203/rs.3.rs-3161608/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
The mechanochemical GTPase dynamin-related protein 1 (Drp1) catalyzes mitochondrial fission, but the regulatory mechanisms remain ambiguous. Here we found that a conserved, intrinsically disordered, six-residue Short Linear Motif at the extreme Drp1 C-terminus, named CT-SLiM, constitutes a critical allosteric site that controls Drp1 structure and function in vitro and in vivo. Extension of the CT-SLiM by non-native residues, or its interaction with the protein partner GIPC-1, constrains Drp1 subunit conformational dynamics, alters self-assembly properties, and limits cooperative GTP hydrolysis, leading to the fission of model membranes in vitro. In vivo, the availability of the native CT-SLiM is a requirement for productive mitochondrial fission, as both non-native extension and deletion of the CT-SLiM severely impair its progression. Thus, contrary to prevailing models, Drp1-catalyzed mitochondrial fission relies on allosteric communication mediated by the CT-SLiM, deceleration of GTPase activity, and coupled changes in subunit architecture and assembly-disassembly dynamics.
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Affiliation(s)
- Isabel Pérez-Jover
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
- Instituto Biofisika, University of the Basque Country, 48940 Leioa, Spain
| | - Kristy Rochon
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Di Hu
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Pooja Madan Mohan
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Isaac Santos-Perez
- Electron Microscopy and Crystallography Center for Cooperative Research in Biosciences (CIC bioGUNE), Bizkaia Science and Technology Park Bld 800, 48160-Derio, Bizkaia, Spain
| | - Julene Ormaetxea Gisasola
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
- Instituto Biofisika, University of the Basque Country, 48940 Leioa, Spain
| | - Juan Manuel Martinez Galvez
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
- Instituto Biofisika, University of the Basque Country, 48940 Leioa, Spain
| | - Jon Agirre
- York Structural Biology Laboratory, Department of Chemistry, University of York, Heslington, YO10 5DD, York, UK
| | - Xin Qi
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Jason A Mears
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
| | - Anna V Shnyrova
- Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
- Instituto Biofisika, University of the Basque Country, 48940 Leioa, Spain
| | - Rajesh Ramachandran
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA
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11
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Ahmed A, Trezza A, Gentile M, Paccagnini E, Panti A, Lupetti P, Spiga O, Bova S, Fusi F. Dynamin-independent Ca V1.2 and K Ca1.1 channels regulation and vascular tone modulation by the mitochondrial fission inhibitors dynasore and dyngo-4a. Eur J Pharmacol 2023; 951:175786. [PMID: 37179045 DOI: 10.1016/j.ejphar.2023.175786] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 05/03/2023] [Accepted: 05/10/2023] [Indexed: 05/15/2023]
Abstract
A role for mitochondrial fission in vascular contraction has been proposed based on the vasorelaxant activity of the dynamin (and mitochondrial fission) inhibitors mdivi-1 and dynasore. However, mdivi-1 is capable to inhibit Ba2+ currents through CaV1.2 channels (IBa1.2), stimulate KCa1.1 channel currents (IKCa1.1), and modulate pathways key to the maintenance of vessel active tone in a dynamin-independent manner. Using a multidisciplinary approach, the present study demonstrates that dynasore, like mdivi-1, is a bi-functional vasodilator, blocking IBa1.2 and stimulating IKCa1.1 in rat tail artery myocytes, as well as promoting relaxation of rat aorta rings pre-contracted by either high K+ or phenylephrine. Conversely, its analogue dyngo-4a, though inhibiting mitochondrial fission triggered by phenylephrine and stimulating IKCa1.1, did not affect IBa1.2 but potentiated both high K+- and phenylephrine-induced contractions. Docking and molecular dynamics simulations identified the molecular basis supporting the different activity of dynasore and dyngo-4a at CaV1.2 and KCa1.1 channels. Mito-tempol only partially counteracted the effects of dynasore and dyngo-4a on phenylephrine-induced tone. In conclusion, the present data, along with previous observations (Ahmed et al., 2022) rise caution for the use of dynasore, mdivi-1, and dyngo-4a as tools to investigate the role of mitochondrial fission in vascular contraction: to this end, a selective dynamin inhibitor and/or a different experimental approach are needed.
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Affiliation(s)
- Amer Ahmed
- Dipartimento di Scienze della Vita, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Alfonso Trezza
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Mariangela Gentile
- Dipartimento di Scienze della Vita, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Eugenio Paccagnini
- Dipartimento di Scienze della Vita, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Alice Panti
- Dipartimento di Scienze della Vita, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Pietro Lupetti
- Dipartimento di Scienze della Vita, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Ottavia Spiga
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, 53100, Siena, Italy
| | - Sergio Bova
- Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padova, Italy
| | - Fabio Fusi
- Dipartimento di Biotecnologie, Chimica e Farmacia, Università di Siena, via A. Moro 2, 53100, Siena, Italy.
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12
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Su Y, Hou C, Wang M, Ren K, Zhou D, Liu X, Zhao S, Liu X. Metformin induces mitochondrial fission and reduces energy metabolism by targeting respiratory chain complex I in hepatic stellate cells to reverse liver fibrosis. Int J Biochem Cell Biol 2023; 157:106375. [PMID: 36716817 DOI: 10.1016/j.biocel.2023.106375] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 12/27/2022] [Accepted: 01/26/2023] [Indexed: 01/30/2023]
Abstract
The activation and proliferation of hepatic stellate cells (HSCs) are critical processes for the treatment of liver fibrosis. It is necessary to identify effective drugs for the treatment of liver fibrosis and elucidate their mechanisms of action. Metformin can inhibit HSCs; however, no systematic studies demonstrating the effects of metformin on mitochondria in HSCs have been reported. This study demonstrated that metformin induces mitochondrial fission by phosphorylating AMPK/DRP1 (S616) in HSCs to decrease the expression of α-SMA and collagen. Additionally, metformin repressed the total ATP production rate, especially the production rate of ATP produced through mitochondrial oxidative phosphorylation, by inhibiting the enzymatic activity of complex I. Further analysis revealed that metformin strongly constrained the transcription of mitochondrial genes (ND1-ND6 and ND4L) that encode the core subunits of respiratory chain I. Upregulation of the mRNA expression of HK2 and GLUT1 slightly enhanced glycolysis. Additionally, metformin increased mitochondrial DNA (mtDNA) copy number to suppress the proliferation and activation of HSCs, indicating that mtDNA copy number can alter the fate of HSCs. In conclusion, metformin can induce mitochondrial fragmentation and low-level energy metabolism in HSCs, thereby suppressing HSCs activation and proliferation to reverse liver fibrosis.
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Affiliation(s)
- Ying Su
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Chenjian Hou
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Meili Wang
- Department of Pathology, Shanghai Fifth People's Hospital, Fudan University, Shanghai 200240, China
| | - Kehan Ren
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Danmei Zhou
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Xiaoli Liu
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Shanyu Zhao
- Department of Pathology, School of Basic Medical Sciences, Fudan University, Shanghai 200032, China
| | - Xiuping Liu
- Department of Pathology, Shanghai Fifth People's Hospital, School of Basic Medical Sciences, Fudan University, Shanghai 200240, China.
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13
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He L, Tronstad KJ, Maheshwari A. Mitochondrial Dynamics during Development. NEWBORN (CLARKSVILLE, MD.) 2023; 2:19-44. [PMID: 37206581 PMCID: PMC10193651 DOI: 10.5005/jp-journals-11002-0053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Mitochondria are dynamic membrane-bound organelles in eukaryotic cells. These are important for the generation of chemical energy needed to power various cellular functions and also support metabolic, energetic, and epigenetic regulation in various cells. These organelles are also important for communication with the nucleus and other cellular structures, to maintain developmental sequences and somatic homeostasis, and for cellular adaptation to stress. Increasing information shows mitochondrial defects as an important cause of inherited disorders in different organ systems. In this article, we provide an extensive review of ontogeny, ultrastructural morphology, biogenesis, functional dynamics, important clinical manifestations of mitochondrial dysfunction, and possibilities for clinical intervention. We present information from our own clinical and laboratory research in conjunction with information collected from an extensive search in the databases PubMed, EMBASE, and Scopus.
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Affiliation(s)
- Ling He
- Department of Pediatrics and Pharmacology, Johns Hopkins University, Baltimore, United States of America
| | | | - Akhil Maheshwari
- Founding Chairman, Global Newborn Society, Clarksville, Maryland, United States of America
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14
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Mears JA, Ramachandran R. Drp1 and the cytoskeleton: mechanistic nexus in mitochondrial division. CURRENT OPINION IN PHYSIOLOGY 2022; 29:100574. [PMID: 36406887 PMCID: PMC9668076 DOI: 10.1016/j.cophys.2022.100574] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dynamin-related protein 1 (Drp1), the master regulator of mitochondrial division (MD), interacts with the cytoskeletal elements, namely filamentous actin (F-actin), microtubules (MT), and septins that coincidentally converge at MD sites. However, the mechanistic contributions of these critical elements to, and their cooperativity in, MD remain poorly characterized. Emergent data indicate that the cytoskeleton plays combinatorial modulator, mediator, and effector roles in MD by 'priming' and 'channeling' Drp1 for mechanoenzymatic membrane remodeling. In this brief review, we will outline our current understanding of Drp1-cytoskeleton interactions, focusing on recent progress in the field and a plausible 'diffusion barrier' role for the cytoskeleton in MD.
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Affiliation(s)
- Jason A. Mears
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH 44106
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH 44106
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH 44106
| | - Rajesh Ramachandran
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH 44106
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH 44106
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15
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Ning P, Jiang X, Yang J, Zhang J, Yang F, Cao H. Mitophagy: A potential therapeutic target for insulin resistance. Front Physiol 2022; 13:957968. [PMID: 36082218 PMCID: PMC9445132 DOI: 10.3389/fphys.2022.957968] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Accepted: 08/01/2022] [Indexed: 11/29/2022] Open
Abstract
Glucose and lipid metabolism disorders caused by insulin resistance (IR) can lead to metabolic disorders such as diabetes, obesity, and the metabolic syndrome. Early and targeted intervention of IR is beneficial for the treatment of various metabolic disorders. Although significant progress has been made in the development of IR drug therapies, the state of the condition has not improved significantly. There is a critical need to identify novel therapeutic targets. Mitophagy is a type of selective autophagy quality control system that is activated to clear damaged and dysfunctional mitochondria. Mitophagy is highly regulated by various signaling pathways, such as the AMPK/mTOR pathway which is involved in the initiation of mitophagy, and the PINK1/Parkin, BNIP3/Nix, and FUNDC1 pathways, which are involved in mitophagosome formation. Mitophagy is involved in numerous human diseases such as neurological disorders, cardiovascular diseases, cancer, and aging. However, recently, there has been an increasing interest in the role of mitophagy in metabolic disorders. There is emerging evidence that normal mitophagy can improve IR. Unfortunately, few studies have investigated the relationship between mitophagy and IR. Therefore, we set out to review the role of mitophagy in IR and explore whether mitophagy may be a potential new target for IR therapy. We hope that this effort serves to stimulate further research in this area.
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Affiliation(s)
- Peng Ning
- Department of Endocrine and Metabolism, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Xiaobo Jiang
- Department of Cardiovascular Medicine, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Jing Yang
- Department of Endocrine and Metabolism, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Jiaxing Zhang
- Department of Endocrine and Metabolism, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
| | - Fan Yang
- Department of Endocrine and Metabolism, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
- *Correspondence: Fan Yang, ; Hongyi Cao,
| | - Hongyi Cao
- Department of Endocrine and Metabolism, Geriatric Diseases Institute of Chengdu/Cancer Prevention and Treatment Institute of Chengdu, Chengdu Fifth People’s Hospital(The Second Clinical Medical College, Affiliated Fifth People’s Hospital of Chengdu University of Traditional Chinese Medicine), Chengdu, China
- *Correspondence: Fan Yang, ; Hongyi Cao,
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16
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Ma K, Bai Y, Li J, Ren Z, Li J, Zhang J, Shan A. Lactobacillus rhamnosus GG ameliorates deoxynivalenol-induced kidney oxidative damage and mitochondrial injury in weaned piglets. Food Funct 2022; 13:3905-3916. [PMID: 35285834 DOI: 10.1039/d2fo00185c] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Deoxynivalenol (DON) is a common mycotoxin that pollutes food crops and adversely affects the health of animals, even humans. Lactobacillus rhamnosus GG (LGG) can alleviate intestinal injury, and anti-inflammatory and antioxidant effects. However, the potential of LGG in alleviating kidney injury induced by DON in piglets remains to be studied. The objective of this study was to investigate the adverse effect of DON on kidney injury and the protective ability of LGG. A total of twenty-seven weaned piglets were divided into three groups: CON group, DON group (3.11 mg kg-1 feed) and LGG + DON group (LGG powder 1 g kg-1 + DON 3.15 mg kg-1 feed). DON increased the MDA content, and decreased antioxidant enzyme activity (GSH-Px) and total antioxidant capacity (P < 0.05). Meanwhile, DON activated the Nrf2 antioxidant pathway. However, LGG supplementation alleviated the damage of DON to the kidney antioxidant system of piglets. Notably, DON significantly reduced the Sirt3 expression (P < 0.05), which was alleviated by LGG addition. The expression of mitochondrial biogenesis related factors such as VDAC1 and Cyt C was up-regulated by DON (P < 0.05), and LGG could improve mitochondrial ultrastructural abnormalities and mitochondrial dysfunction. In addition, LGG mitigated DON-induced mitochondrial fusion inhibition, and prevented DON-mediated mitochondrial autophagy. In conclusion, LGG play a protective role in DON-induced kidney toxicity, and dietary intervention may be a strategy to reduce mycotoxins.
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Affiliation(s)
- Kaidi Ma
- Institute of Animal Nutrition, Northeast Agricultural University, No. 600, Changjiang Road, Harbin 150030, P. R. China.
| | - Yongsong Bai
- Institute of Animal Nutrition, Northeast Agricultural University, No. 600, Changjiang Road, Harbin 150030, P. R. China.
| | - Jibo Li
- Institute of Animal Nutrition, Northeast Agricultural University, No. 600, Changjiang Road, Harbin 150030, P. R. China.
| | - Zhongshuai Ren
- College of Animal Science, Jilin University, Changchun 130062, P. R. China.
| | - Jianping Li
- Institute of Animal Nutrition, Northeast Agricultural University, No. 600, Changjiang Road, Harbin 150030, P. R. China.
| | - Jing Zhang
- College of Animal Science, Jilin University, Changchun 130062, P. R. China.
| | - Anshan Shan
- Institute of Animal Nutrition, Northeast Agricultural University, No. 600, Changjiang Road, Harbin 150030, P. R. China.
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17
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Metal-Binding Propensity in the Mitochondrial Dynamin-Related Protein 1. J Membr Biol 2022; 255:143-150. [PMID: 35218392 DOI: 10.1007/s00232-022-00221-5] [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: 01/16/2022] [Accepted: 02/14/2022] [Indexed: 10/19/2022]
Abstract
Dynamin-related protein1 (Drp1) functions to divide mitochondria and peroxisomes by binding specific adaptor proteins and lipids, both of which are integral to the limiting organellar membrane. In efforts to understand how such multivalent interactions regulate Drp1 functions, in vitro reconstitution schemes rely on recruiting soluble portions of the adaptors appended with genetically encoded polyhistidine tags onto membranes containing Ni2+-bound chelator lipids. These strategies are facile and circumvent the challenge in working with membrane proteins but assume that binding is specific to proteins carrying the polyhistidine tag. Here, we find using chelator lipids and chelator beads that both native and recombinant Drp1 directly bind Ni2+ ions. Metal binding, therefore, represents a potential strategy to deplete or purify Drp1 from native tissue lysates. Importantly, high concentrations of the metal in solution inhibit GTP hydrolysis and renders Drp1 inactive in membrane fission. Together, our results emphasize a metal-binding propensity, which could significantly impact Drp1 functions.
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18
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Chen Y, Culetto E, Legouis R. The strange case of Drp1 in autophagy: Jekyll and Hyde? Bioessays 2022; 44:e2100271. [PMID: 35166388 DOI: 10.1002/bies.202100271] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 01/31/2022] [Accepted: 02/01/2022] [Indexed: 12/27/2022]
Abstract
There is a debate regarding the function of Drp1, a GTPase involved in mitochondrial fission, during the elimination of mitochondria by autophagy. A number of experiments indicate that Drp1 is needed to eliminate mitochondria during mitophagy, either by reducing the mitochondrial size or by providing a noncanonical mitophagy function. Yet, other convincing experimental results support the conclusion that Drp1 is not necessary. Here, we review the possible functions for Drp1 in mitophagy and autophagy, depending on tissues, organisms and stresses, and discuss these apparent discrepancies. In this regard, it appears that the reduction of mitochondria size is often required for mitophagy but not always in a Drp1-dependent manner. Finally, we speculate on Drp1-independent mitochondrial fission mechanism that may take place during mitophagy and on noncanonical roles, which Drp1 may play such as modulating organelle contact sites dynamic during the autophagosome formation.
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Affiliation(s)
- Yanfang Chen
- College of Life Sciences, Animal Ressources Center, Nankai University, Tianjin, China
| | - Emmanuel Culetto
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, Paris, France.,INSERM, U1280, Gif-sur-Yvette, France
| | - Renaud Legouis
- Université Paris-Saclay, CEA, CNRS, Institute for Integrative Biology of the Cell (I2BC), Institute for Integrative Biology of the Cell (I2BC), Gif-sur-Yvette, Paris, France.,INSERM, U1280, Gif-sur-Yvette, France
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19
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Wang X, Yin L, Wen Y, Yuan S. Mitochondrial regulation during male germ cell development. Cell Mol Life Sci 2022; 79:91. [PMID: 35072818 PMCID: PMC11072027 DOI: 10.1007/s00018-022-04134-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 12/21/2021] [Accepted: 01/05/2022] [Indexed: 12/16/2022]
Abstract
Mitochondria tailor their morphology to execute their specialized functions in different cell types and/or different environments. During spermatogenesis, mitochondria undergo continuous morphological and distributional changes with germ cell development. Deficiencies in these processes lead to mitochondrial dysfunction and abnormal spermatogenesis, thereby causing male infertility. In recent years, mitochondria have attracted considerable attention because of their unique role in the regulation of piRNA biogenesis in male germ cells. In this review, we describe the varied characters of mitochondria and focus on key mitochondrial factors that play pivotal roles in the regulation of spermatogenesis, from primordial germ cells to spermatozoa, especially concerning metabolic shift, stemness and reprogramming, mitochondrial transformation and rearrangement, and mitochondrial defects in human sperm. Further, we discuss the molecular mechanisms underlying these processes.
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Affiliation(s)
- Xiaoli Wang
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Lisha Yin
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yujiao Wen
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Shuiqiao Yuan
- Institute of Reproductive Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
- Laboratory Animal Center, Huazhong University of Science and Technology, Wuhan, 430030, China.
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20
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Tian H, Chen X, Liao J, Yang T, Cheng S, Mei Z, Ge J. Mitochondrial quality control in stroke: From the mechanisms to therapeutic potentials. J Cell Mol Med 2022; 26:1000-1012. [PMID: 35040556 PMCID: PMC8831937 DOI: 10.1111/jcmm.17189] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/17/2021] [Accepted: 01/03/2022] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial damage is a critical contributor to stroke‐induced injury, and mitochondrial quality control (MQC) is the cornerstone of restoring mitochondrial homeostasis and plays an indispensable role in alleviating pathological process of stroke. Mitochondria quality control promotes neuronal survival via various adaptive responses for preserving mitochondria structure, morphology, quantity and function. The processes of mitochondrial fission and fusion allow for damaged mitochondria to be segregated and facilitate the equilibration of mitochondrial components such as DNA, proteins and metabolites. The process of mitophagy is responsible for the degradation and recycling of damaged mitochondria. This review aims to offer a synopsis of the molecular mechanisms involved in MQC for recapitulating our current understanding of the complex role that MQC plays in the progression of stroke. Speculating on the prospect that targeted manipulation of MQC mechanisms may be exploited for the rationale design of novel therapeutic interventions in the ischaemic stroke and haemorrhagic stroke. In the review, we highlight the potential of MQC as therapeutic targets for stroke treatment and provide valuable insights for clinical strategies.
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Affiliation(s)
- Heyan Tian
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Xiangyu Chen
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Jun Liao
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Tong Yang
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Shaowu Cheng
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Zhigang Mei
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
| | - Jinwen Ge
- Key Laboratory of Hunan Province for Integrated Traditional Chinese and Western Medicine on Prevention and Treatment of Cardio-cerebral Disease, Hunan University of Chinese Medicine, Changsha, China
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21
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Przygrodzka E, Plewes MR, Davis JS. Luteinizing Hormone Regulation of Inter-Organelle Communication and Fate of the Corpus Luteum. Int J Mol Sci 2021; 22:9972. [PMID: 34576135 PMCID: PMC8470545 DOI: 10.3390/ijms22189972] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 09/10/2021] [Accepted: 09/12/2021] [Indexed: 12/18/2022] Open
Abstract
The corpus luteum is an endocrine gland that synthesizes the steroid hormone progesterone. luteinizing hormone (LH) is a key luteotropic hormone that stimulates ovulation, luteal development, progesterone biosynthesis, and maintenance of the corpus luteum. Luteotropic and luteolytic factors precisely regulate luteal structure and function; yet, despite recent scientific progress within the past few years, the exact mechanisms remain largely unknown. In the present review, we summarize the recent progress towards understanding cellular changes induced by LH in steroidogenic luteal cells. Herein, we will focus on the effects of LH on inter-organelle communication and steroid biosynthesis, and how LH regulates key protein kinases (i.e., AMPK and MTOR) responsible for controlling steroidogenesis and autophagy in luteal cells.
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Affiliation(s)
- Emilia Przygrodzka
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
| | - Michele R. Plewes
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
- Veterans Affairs Nebraska Western Iowa Health Care System, 4101 Woolworth Ave, Omaha, NE 68105, USA
| | - John S. Davis
- Olson Center for Women’s Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, Nebraska Medical Center, Omaha, NE 68198-3255, USA; (E.P.); (M.R.P.)
- Veterans Affairs Nebraska Western Iowa Health Care System, 4101 Woolworth Ave, Omaha, NE 68105, USA
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22
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Liu A, Kage F, Higgs HN. Mff oligomerization is required for Drp1 activation and synergy with actin filaments during mitochondrial division. Mol Biol Cell 2021; 32:ar5. [PMID: 34347505 PMCID: PMC8684745 DOI: 10.1091/mbc.e21-04-0224] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Mitochondrial division is an important cellular process in both normal and pathological conditions. The dynamin GTPase Drp1 is a central mitochondrial division protein, driving constriction of the outer mitochondrial membrane. In mammals, the outer mitochondrial membrane protein Mff is a key receptor for recruiting Drp1 from the cytosol to the mitochondrion. Actin filaments are also important in Drp1 recruitment and activation. The manner in which Mff and actin work together in Drp1 activation is unknown. Here, we show that Mff is an oligomer (most likely a trimer) that dynamically associates and disassociates through its C-terminal coiled-coil, with a Kd in the range of 10 µM. Dynamic Mff oligomerization is required for Drp1 activation. While not binding Mff directly, actin filaments enhance Mff-mediated Drp1 activation by lowering the effective Mff concentration 10-fold. Total internal reflection microscopy assays using purified proteins show that Mff interacts with Drp1 on actin filaments in a manner dependent on Mff oligomerization. In U2OS cells, oligomerization-defective Mff does not effectively rescue three defects in Mff knock-out cells: mitochondrial division, mitochondrial Drp1 recruitment, and peroxisome division. The ability of Mff to assemble into puncta on mitochondria depends on its oligomerization, as well as on actin filaments and Drp1.
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Affiliation(s)
- Ao Liu
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
| | - Frieda Kage
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
| | - Henry N Higgs
- Department of Biochemistry and Cell Biology, Geisel School of Medicine at Dartmouth College, Hanover NH 03755, USA
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23
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Mahajan M, Bharambe N, Shang Y, Lu B, Mandal A, Madan Mohan P, Wang R, Boatz JC, Manuel Martinez Galvez J, Shnyrova AV, Qi X, Buck M, van der Wel PCA, Ramachandran R. NMR identification of a conserved Drp1 cardiolipin-binding motif essential for stress-induced mitochondrial fission. Proc Natl Acad Sci U S A 2021; 118:e2023079118. [PMID: 34261790 PMCID: PMC8307854 DOI: 10.1073/pnas.2023079118] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Mitochondria form tubular networks that undergo coordinated cycles of fission and fusion. Emerging evidence suggests that a direct yet unresolved interaction of the mechanoenzymatic GTPase dynamin-related protein 1 (Drp1) with mitochondrial outer membrane-localized cardiolipin (CL), externalized under stress conditions including mitophagy, catalyzes essential mitochondrial hyperfragmentation. Here, using a comprehensive set of structural, biophysical, and cell biological tools, we have uncovered a CL-binding motif (CBM) conserved between the Drp1 variable domain (VD) and the unrelated ADP/ATP carrier (AAC/ANT) that intercalates into the membrane core to effect specific CL interactions. CBM mutations that weaken VD-CL interactions manifestly impair Drp1-dependent fission under stress conditions and induce "donut" mitochondria formation. Importantly, VD membrane insertion and GTP-dependent conformational rearrangements mediate only transient CL nonbilayer topological forays and high local membrane constriction, indicating that Drp1-CL interactions alone are insufficient for fission. Our studies establish the structural and mechanistic bases of Drp1-CL interactions in stress-induced mitochondrial fission.
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Affiliation(s)
- Mukesh Mahajan
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Nikhil Bharambe
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Yutong Shang
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Bin Lu
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Abhishek Mandal
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Pooja Madan Mohan
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Rihua Wang
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
| | - Jennifer C Boatz
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Juan Manuel Martinez Galvez
- Instituto Biofisika and Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Anna V Shnyrova
- Instituto Biofisika and Department of Biochemistry and Molecular Biology, University of the Basque Country, 48940 Leioa, Spain
| | - Xin Qi
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
- Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH 44106
| | - Matthias Buck
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, OH 44106
| | - Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
- Zernike Institute for Advanced Materials, University of Groningen, 9700 AB Groningen, The Netherlands
| | - Rajesh Ramachandran
- Department of Physiology and Biophysics, Case Western Reserve University, Cleveland, OH 44106;
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University, Cleveland, OH 44106
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24
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Lima AR, Correia M, Santos L, Tavares C, Rios E, Canberk S, Soares P, Sobrinho-Simões M, Melo M, Máximo V. S616-p-DRP1 associates with locally invasive behavior of follicular cell-derived thyroid carcinoma. Endocrine 2021; 73:85-97. [PMID: 33219495 DOI: 10.1007/s12020-020-02546-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 11/02/2020] [Indexed: 12/14/2022]
Abstract
PURPOSE Dynamin-related protein 1 (DRP1), a mitochondrial fission protein, and its active form phosphorylated at Serine 616 (S616-p-DRP1) have been increasingly associated with tumorigenesis and invasion in various tumor models, including oncocytic thyroid cancer (TC). In this study, the expression of DRP1 and S616-p-DRP1 and its relationship with patients' clinicopathological characteristics, tumor genetic profiles, and clinical outcomes were assessed in a large series of follicular cell-derived TC (FCDTC). METHODS Retrospective biomarker study characterizing the clinicopathological and immunochemistry DRP1 and S616-p-DRP1 expression of a series of 259 patients with FCDTC followed in two University Hospitals. RESULTS DRP1 expression was positive in 65.3% (169/259) of the cases, while the expression of the S616-p-DRP1 was positive in only 17.3% (17/98). DRP1-positive expression was significantly associated with differentiated tumors (67.7 vs. 48.0%; P = 0.049), non-encapsulated tumors (73.8 vs. 57.4%; P = 0.011) and thyroid capsule invasion (73.4 vs. 57.5%; P = 0.013). S616-p-DRP1-positive expression was significantly associated with tumor infiltrative margins (88.9 vs. 11.1%; P = 0.033), thyroid capsule invasion (29.8 vs. 3.1%; P = 0.043), lymph node metastases (23.3 vs. 8.1%; P = 0.012), and higher mean cumulative radioiodine dosage (317.4 ± 265.0 mCi vs. 202.5 ± 217.7 mCi; P = 0.038). S616-p-DRP1 expression was negatively associated with oncocytic phenotype (0.0 vs. 26.2%; P = 0.028). CONCLUSIONS S616-p-DRP1 is a better candidate than DRP1 to identify tumors with locally invasive behavior. Prospective studies should be pursued to assess S616-p-DRP1 role as a molecular marker of malignancy in TC and in patients' risk assessment.
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Affiliation(s)
- Ana Rita Lima
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal.
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal.
- Faculty of Medicine of the University of Porto (FMUP), Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal.
| | - Marcelo Correia
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
| | - Liliana Santos
- Coimbra Institute for Clinical and Biomedical Research (iCBR), Faculty of Medicine, University of Coimbra, Coimbra, Portugal
- CIBB Consortium, University of Coimbra, Coimbra, Portugal
| | - Catarina Tavares
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
| | - Elisabete Rios
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Faculty of Medicine of the University of Porto (FMUP), Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal
- Department of Pathology, Faculty of Medicine of the University of Porto (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
- Department of Pathology, Centro Hospitalar São João, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
| | - Sule Canberk
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Faculty of Medicine of the University of Porto (FMUP), Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal
- Abel Salazar Institute of Biomedical Sciences (ICBAS), University of Porto, Rua de Jorge Viterbo Ferreira 228, 4050-313, Porto, Portugal
| | - Paula Soares
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Faculty of Medicine of the University of Porto (FMUP), Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal
- Department of Pathology, Faculty of Medicine of the University of Porto (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
| | - Manuel Sobrinho-Simões
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Department of Pathology, Faculty of Medicine of the University of Porto (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
- Department of Pathology, Centro Hospitalar São João, Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
| | - Miguel Melo
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Department of Endocrinology, Diabetes and Metabolism, Centro Hospitalar e Universitário de Coimbra (CHUC), Praceta Prof. Mota Pinto, 3000-075, Coimbra, Portugal
- Faculty of Medicine of the University of Coimbra (FMUC), Rua Larga, 3004-504, Coimbra, Portugal
| | - Valdemar Máximo
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Rua Alfredo Allen 208, 4200-135, Porto, Portugal
- Cancer Signaling and Metabolism Group, Institute of Molecular Pathology and Immunology of the University of Porto (Ipatimup), Rua Júlio Amaral de Carvalho 45, 4200-135, Porto, Portugal
- Faculty of Medicine of the University of Porto (FMUP), Alameda Professor Hernâni Monteiro, 4200-319, Porto, Portugal
- Department of Pathology, Faculty of Medicine of the University of Porto (FMUP), Alameda Prof. Hernâni Monteiro, 4200-319, Porto, Portugal
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25
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Li M, Sun W, Tyurin VA, DeLucia M, Ahn J, Kagan VE, van der Wel PCA. Activation of Cytochrome C Peroxidase Function Through Coordinated Foldon Loop Dynamics upon Interaction with Anionic Lipids. J Mol Biol 2021; 433:167057. [PMID: 34033821 DOI: 10.1016/j.jmb.2021.167057] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2021] [Revised: 05/07/2021] [Accepted: 05/13/2021] [Indexed: 02/06/2023]
Abstract
Cardiolipin (CL) is a mitochondrial anionic lipid that plays important roles in the regulation and signaling of mitochondrial apoptosis. CL peroxidation catalyzed by the assembly of CL-cytochrome c (cyt c) complexes at the inner mitochondrial membrane is a critical checkpoint. The structural changes in the protein, associated with peroxidase activation by CL and different anionic lipids, are not known at a molecular level. To better understand these peripheral protein-lipid interactions, we compare how phosphatidylglycerol (PG) and CL lipids trigger cyt c peroxidase activation, and correlate functional differences to structural and motional changes in membrane-associated cyt c. Structural and motional studies of the bound protein are enabled by magic angle spinning solid state NMR spectroscopy, while lipid peroxidase activity is assayed by mass spectrometry. PG binding results in a surface-bound state that preserves a nativelike fold, which nonetheless allows for significant peroxidase activity, though at a lower level than binding its native substrate CL. Lipid-specific differences in peroxidase activation are found to correlate to corresponding differences in lipid-induced protein mobility, affecting specific protein segments. The dynamics of omega loops C and D are upregulated by CL binding, in a way that is remarkably controlled by the protein:lipid stoichiometry. In contrast to complete chemical denaturation, membrane-induced protein destabilization reflects a destabilization of select cyt c foldons, while the energetically most stable helices are preserved. Our studies illuminate the interplay of protein and lipid dynamics in the creation of lipid peroxidase-active proteolipid complexes implicated in early stages of mitochondrial apoptosis.
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Affiliation(s)
- Mingyue Li
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Wanyang Sun
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Vladimir A Tyurin
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Maria DeLucia
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Jinwoo Ahn
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA
| | - Valerian E Kagan
- Department of Environmental and Occupational Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Center for Free Radical and Antioxidant Health, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Chemistry, University of Pittsburgh, Pittsburgh, PA 15213, USA; Department of Pharmacology and Chemical Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Institute for Regenerative Medicine, IM Sechenov, Moscow State Medical University, Moscow 119146, Russian Federation
| | - Patrick C A van der Wel
- Department of Structural Biology, University of Pittsburgh, Pittsburgh, PA 15213, USA; Zernike Institute for Advanced Materials, University of Groningen, Groningen, the Netherlands.
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26
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Rahman FA, Quadrilatero J. Mitochondrial network remodeling: an important feature of myogenesis and skeletal muscle regeneration. Cell Mol Life Sci 2021; 78:4653-4675. [PMID: 33751143 PMCID: PMC11072563 DOI: 10.1007/s00018-021-03807-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 02/23/2021] [Accepted: 03/03/2021] [Indexed: 12/13/2022]
Abstract
The remodeling of the mitochondrial network is a critical process in maintaining cellular homeostasis and is intimately related to mitochondrial function. The interplay between the formation of new mitochondria (biogenesis) and the removal of damaged mitochondria (mitophagy) provide a means for the repopulation of the mitochondrial network. Additionally, mitochondrial fission and fusion serve as a bridge between biogenesis and mitophagy. In recent years, the importance of these processes has been characterised in multiple tissue- and cell-types, and under various conditions. In skeletal muscle, the robust remodeling of the mitochondrial network is observed, particularly after injury where large portions of the tissue/cell structures are damaged. The significance of mitochondrial remodeling in regulating skeletal muscle regeneration has been widely studied, with alterations in mitochondrial remodeling processes leading to incomplete regeneration and impaired skeletal muscle function. Needless to say, important questions related to mitochondrial remodeling and skeletal muscle regeneration still remain unanswered and require further investigation. Therefore, this review will discuss the known molecular mechanisms of mitochondrial network remodeling, as well as integrate these mechanisms and discuss their relevance in myogenesis and regenerating skeletal muscle.
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Affiliation(s)
- Fasih Ahmad Rahman
- Department of Kinesiology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada
| | - Joe Quadrilatero
- Department of Kinesiology, University of Waterloo, Waterloo, ON, N2L 3G1, Canada.
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27
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Alsayyah C, Ozturk O, Cavellini L, Belgareh-Touzé N, Cohen MM. The regulation of mitochondrial homeostasis by the ubiquitin proteasome system. BIOCHIMICA ET BIOPHYSICA ACTA-BIOENERGETICS 2020; 1861:148302. [PMID: 32861697 DOI: 10.1016/j.bbabio.2020.148302] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/05/2020] [Accepted: 08/24/2020] [Indexed: 02/07/2023]
Abstract
From mitochondrial quality control pathways to the regulation of specific functions, the Ubiquitin Proteasome System (UPS) could be compared to a Swiss knife without which mitochondria could not maintain its integrity in the cell. Here, we review the mechanisms that the UPS employs to regulate mitochondrial function and efficiency. For this purpose, we depict how Ubiquitin and the Proteasome participate in diverse quality control pathways that safeguard entry into the mitochondrial compartment. A focus is then achieved on the UPS-mediated control of the yeast mitofusin Fzo1 which provides insights into the complex regulation of this particular protein in mitochondrial fusion. We ultimately dissect the mechanisms by which the UPS controls the degradation of mitochondria by autophagy in both mammalian and yeast systems. This organization should offer a useful overview of this abundant but fascinating literature on the crosstalks between mitochondria and the UPS.
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Affiliation(s)
- Cynthia Alsayyah
- Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, F-75005 Paris, France
| | - Oznur Ozturk
- Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, F-75005 Paris, France
| | - Laetitia Cavellini
- Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, F-75005 Paris, France
| | - Naïma Belgareh-Touzé
- Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, F-75005 Paris, France
| | - Mickael M Cohen
- Sorbonne Université, CNRS, UMR8226, Institut de Biologie Physico-Chimique, Laboratoire de Biologie Moléculaire et Cellulaire des Eucaryotes, F-75005 Paris, France.
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28
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Murata D, Yamada T, Tokuyama T, Arai K, Quirós PM, López-Otín C, Iijima M, Sesaki H. Mitochondrial Safeguard: a stress response that offsets extreme fusion and protects respiratory function via flickering-induced Oma1 activation. EMBO J 2020; 39:e105074. [PMID: 33200421 DOI: 10.15252/embj.2020105074] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 10/15/2020] [Accepted: 10/22/2020] [Indexed: 12/22/2022] Open
Abstract
The connectivity of mitochondria is regulated by a balance between fusion and division. Many human diseases are associated with excessive mitochondrial connectivity due to impaired Drp1, a dynamin-related GTPase that mediates division. Here, we report a mitochondrial stress response, named mitochondrial safeguard, that adjusts the balance of fusion and division in response to increased mitochondrial connectivity. In cells lacking Drp1, mitochondria undergo hyperfusion. However, hyperfusion does not completely connect mitochondria because Opa1 and mitofusin 1, two other dynamin-related GTPases that mediate fusion, become proteolytically inactivated. Pharmacological and genetic experiments show that the activity of Oma1, a metalloprotease that cleaves Opa1, is regulated by short pulses of the membrane depolarization without affecting the overall membrane potential in Drp1-knockout cells. Re-activation of Opa1 and Mitofusin 1 in Drp1-knockout cells further connects mitochondria beyond hyperfusion, termed extreme fusion, leading to bioenergetic deficits. These findings reveal an unforeseen safeguard mechanism that prevents extreme fusion of mitochondria, thereby maintaining mitochondrial function when the balance is shifted to excessive connectivity.
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Affiliation(s)
- Daisuke Murata
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Tatsuya Yamada
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Takeshi Tokuyama
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Kenta Arai
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Pedro M Quirós
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Instituto Universitario de Oncología, Universidad de Oviedo, Oviedo, Spain
| | - Carlos López-Otín
- Departamento de Bioquímica y Biología Molecular, Facultad de Medicina, Instituto Universitario de Oncología, Universidad de Oviedo, Oviedo, Spain
| | - Miho Iijima
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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29
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Murata D, Arai K, Iijima M, Sesaki H. Mitochondrial division, fusion and degradation. J Biochem 2020; 167:233-241. [PMID: 31800050 DOI: 10.1093/jb/mvz106] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Accepted: 11/17/2019] [Indexed: 12/11/2022] Open
Abstract
The mitochondrion is an essential organelle for a wide range of cellular processes, including energy production, metabolism, signal transduction and cell death. To execute these functions, mitochondria regulate their size, number, morphology and distribution in cells via mitochondrial division and fusion. In addition, mitochondrial division and fusion control the autophagic degradation of dysfunctional mitochondria to maintain a healthy population. Defects in these dynamic membrane processes are linked to many human diseases that include metabolic syndrome, myopathy and neurodegenerative disorders. In the last several years, our fundamental understanding of mitochondrial fusion, division and degradation has been significantly advanced by high resolution structural analyses, protein-lipid biochemistry, super resolution microscopy and in vivo analyses using animal models. Here, we summarize and discuss this exciting recent progress in the mechanism and function of mitochondrial division and fusion.
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Affiliation(s)
- Daisuke Murata
- Department of Cell Biology, Johns Hopkins University School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205, USA
| | - Kenta Arai
- Department of Cell Biology, Johns Hopkins University School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205, USA
| | - Miho Iijima
- Department of Cell Biology, Johns Hopkins University School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205, USA
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, 725 N. Wolfe St., Baltimore, MD 21205, USA
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30
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Membrane Curvature, Trans-Membrane Area Asymmetry, Budding, Fission and Organelle Geometry. Int J Mol Sci 2020; 21:ijms21207594. [PMID: 33066582 PMCID: PMC7590041 DOI: 10.3390/ijms21207594] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 10/08/2020] [Accepted: 10/09/2020] [Indexed: 01/02/2023] Open
Abstract
In biology, the modern scientific fashion is to mostly study proteins. Much less attention is paid to lipids. However, lipids themselves are extremely important for the formation and functioning of cellular membrane organelles. Here, the role of the geometry of the lipid bilayer in regulation of organelle shape is analyzed. It is proposed that during rapid shape transition, the number of lipid heads and their size (i.e., due to the change in lipid head charge) inside lipid leaflets modulates the geometrical properties of organelles, in particular their membrane curvature. Insertion of proteins into a lipid bilayer and the shape of protein trans-membrane domains also affect the trans-membrane asymmetry between surface areas of luminal and cytosol leaflets of the membrane. In the cases where lipid molecules with a specific shape are not predominant, the shape of lipids (cylindrical, conical, or wedge-like) is less important for the regulation of membrane curvature, due to the flexibility of their acyl chains and their high ability to diffuse.
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Montecinos-Franjola F, Bauer BL, Mears JA, Ramachandran R. GFP fluorescence tagging alters dynamin-related protein 1 oligomerization dynamics and creates disassembly-refractory puncta to mediate mitochondrial fission. Sci Rep 2020; 10:14777. [PMID: 32901052 PMCID: PMC7479153 DOI: 10.1038/s41598-020-71655-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Accepted: 08/19/2020] [Indexed: 01/22/2023] Open
Abstract
Green fluorescent protein (GFP)-tagging is the prevalent strategy to monitor protein dynamics in living cells. However, the consequences of appending the bulky GFP moiety to the protein of interest are rarely investigated. Here, using a powerful combination of quantitative fluorescence spectroscopic and imaging techniques, we have examined the oligomerization dynamics of the GFP-tagged mitochondrial fission GTPase dynamin-related protein 1 (Drp1) both in vitro and in vivo. We find that GFP-tagged Drp1 exhibits impaired oligomerization equilibria in solution that corresponds to a greatly diminished cooperative GTPase activity in comparison to native Drp1. Consequently, GFP-tagged Drp1 constitutes aberrantly stable, GTP-resistant supramolecular assemblies both in vitro and in vivo, neither of which reflects a more dynamic native Drp1 oligomerization state. Indeed, GFP-tagged Drp1 is detected more frequently per unit length over mitochondria in Drp1-null mouse embryonic fibroblasts (MEFs) compared to wild-type (wt) MEFs, indicating that the drastically reduced GTP turnover restricts oligomer disassembly from the mitochondrial surface relative to mixed oligomers comprising native and GFP-tagged Drp1. Yet, GFP-tagged Drp1 retains the capacity to mediate membrane constriction in vitro and mitochondrial division in vivo. These findings suggest that instead of robust assembly-disassembly dynamics, persistent Drp1 higher-order oligomerization over membranes is sufficient for mitochondrial fission.
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Affiliation(s)
- Felipe Montecinos-Franjola
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Brianna L Bauer
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Jason A Mears
- Department of Pharmacology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.,Center for Mitochondrial Diseases, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.,Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA
| | - Rajesh Ramachandran
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA. .,Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH, 44106, USA.
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Tolosa-Díaz A, Almendro-Vedia VG, Natale P, López-Montero I. The GDP-Bound State of Mitochondrial Mfn1 Induces Membrane Adhesion of Apposing Lipid Vesicles through a Cooperative Binding Mechanism. Biomolecules 2020; 10:biom10071085. [PMID: 32708307 PMCID: PMC7407159 DOI: 10.3390/biom10071085] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 07/10/2020] [Accepted: 07/17/2020] [Indexed: 01/01/2023] Open
Abstract
Mitochondria are double-membrane organelles that continuously undergo fission and fusion. Outer mitochondrial membrane fusion is mediated by the membrane proteins mitofusin 1 (Mfn1) and mitofusin 2 (Mfn2), carrying a GTP hydrolyzing domain (GTPase) and two coiled-coil repeats. The detailed mechanism on how the GTP hydrolysis allows Mfns to approach adjacent membranes into proximity and promote their fusion is currently under debate. Using model membranes built up as giant unilamellar vesicles (GUVs), we show here that Mfn1 promotes membrane adhesion of apposing lipid vesicles. The adhesion forces were sustained by the GDP-bound state of Mfn1 after GTP hydrolysis. In contrast, the incubation with the GDP:AlF4−, which mimics the GTP transition state, did not induce membrane adhesion. Due to the flexible nature of lipid membranes, the adhesion strength depended on the surface concentration of Mfn1 through a cooperative binding mechanism. We discuss a possible scenario for the outer mitochondrial membrane fusion based on the modulated action of Mfn1.
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Affiliation(s)
- Andrés Tolosa-Díaz
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Víctor G. Almendro-Vedia
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
| | - Paolo Natale
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
| | - Iván López-Montero
- Dto. Química Física, Universidad Complutense de Madrid, Avenida Complutense s/n, 28040 Madrid, Spain; (A.T.-D.); (V.G.A.-V.)
- Instituto de Investigación Biomédica Hospital Doce de Octubre (imas12), Avenida de Córdoba s/n, 28041 Madrid, Spain
- Correspondence: (P.N.); (I.L.-M.)
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33
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Monolysocardiolipin (MLCL) interactions with mitochondrial membrane proteins. Biochem Soc Trans 2020; 48:993-1004. [PMID: 32453413 PMCID: PMC7329354 DOI: 10.1042/bst20190932] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 04/22/2020] [Accepted: 04/27/2020] [Indexed: 12/27/2022]
Abstract
Monolysocardiolipin (MLCL) is a three-tailed variant of cardiolipin (CL), the signature lipid of mitochondria. MLCL is not normally found in healthy tissue but accumulates in mitochondria of people with Barth syndrome (BTHS), with an overall increase in the MLCL:CL ratio. The reason for MLCL accumulation remains to be fully understood. The effect of MLCL build-up and decreased CL content in causing the characteristics of BTHS are also unclear. In both cases, an understanding of the nature of MLCL interaction with mitochondrial proteins will be key. Recent work has shown that MLCL associates less tightly than CL with proteins in the mitochondrial inner membrane, suggesting that MLCL accumulation is a result of CL degradation, and that the lack of MLCL–protein interactions compromises the stability of the protein-dense mitochondrial inner membrane, leading to a decrease in optimal respiration. There is some data on MLCL–protein interactions for proteins involved in the respiratory chain and in apoptosis, but there remains much to be understood regarding the nature of MLCL–protein interactions. Recent developments in structural, analytical and computational approaches mean that these investigations are now possible. Such an understanding will be key to further insights into how MLCL accumulation impacts mitochondrial membranes. In turn, these insights will help to support the development of therapies for people with BTHS and give a broader understanding of other diseases involving defective CL content.
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Natarajan V, Chawla R, Mah T, Vivekanandan R, Tan SY, Sato PY, Mallilankaraman K. Mitochondrial Dysfunction in Age-Related Metabolic Disorders. Proteomics 2020; 20:e1800404. [PMID: 32131138 DOI: 10.1002/pmic.201800404] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2019] [Revised: 02/07/2020] [Indexed: 12/16/2022]
Abstract
Aging is a natural biological process in living organisms characterized by receding bioenergetics. Mitochondria are crucial for cellular bioenergetics and thus an important contributor to age-related energetics deterioration. In addition, mitochondria play a major role in calcium signaling, redox homeostasis, and thermogenesis making this organelle a major cellular component that dictates the fate of a cell. To maintain its quantity and quality, mitochondria undergo multiple processes such as fission, fusion, and mitophagy to eliminate or replace damaged mitochondria. While this bioenergetics machinery is properly protected, the functional decline associated with age and age-related metabolic diseases is mostly a result of failure in such protective mechanisms. In addition, metabolic by-products like reactive oxygen species also aid in this destructive pathway. Mitochondrial dysfunction has always been thought to be associated with diseases. Moreover, studies in recent years have pointed out that aging contributes to the decay of mitochondrial health by promoting imbalances in key mitochondrial-regulated pathways. Hence, it is crucial to understand the nexus of mitochondrial dysfunction in age-related diseases. This review focuses on various aspects of basic mitochondrial biology and its status in aging and age-related metabolic diseases.
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Affiliation(s)
- Venkateswaran Natarajan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Ritu Chawla
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Tania Mah
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Rajesh Vivekanandan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Shu Yi Tan
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore
| | - Priscila Y Sato
- Department of Pharmacology and Physiology, Drexel University College of Medicine, Philadelphia, 19102-1902, USA
| | - Karthik Mallilankaraman
- Mitochondrial Physiology and Metabolism Lab, Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, 117593, Singapore.,Center for Healthy Longevity, National University Health System, Singapore, 119228, Singapore
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35
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Plewes MR, Hou X, Talbott HA, Zhang P, Wood JR, Cupp AS, Davis JS. Luteinizing hormone regulates the phosphorylation and localization of the mitochondrial effector dynamin-related protein-1 (DRP1) and steroidogenesis in the bovine corpus luteum. FASEB J 2020; 34:5299-5316. [PMID: 32077149 DOI: 10.1096/fj.201902958r] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 02/04/2020] [Accepted: 02/04/2020] [Indexed: 12/31/2022]
Abstract
The corpus luteum is an endocrine gland that synthesizes and secretes progesterone. Luteinizing hormone (LH) activates protein kinase A (PKA) signaling in luteal cells, increasing delivery of substrate to mitochondria for progesterone production. Mitochondria maintain a highly regulated equilibrium between fusion and fission in order to sustain biological function. Dynamin-related protein 1 (DRP1), is a key mediator of mitochondrial fission. The mechanism by which DRP1 is regulated in the ovary is largely unknown. We hypothesize that LH via PKA differentially regulates the phosphorylation of DRP1 on Ser616 and Ser637 in bovine luteal cells. In primary cultures of steroidogenic small luteal cells (SLCs), LH, and forskolin stimulated phosphorylation of DRP1 (Ser 637), and inhibited phosphorylation of DRP1 (Ser 616). Overexpression of a PKA inhibitor blocked the effects of LH and forskolin on DRP1 phosphorylation. In addition, LH decreased the association of DRP1 with the mitochondria. Genetic knockdown of the DRP1 mitochondria receptor, and a small molecule inhibitor of DRP1 increased basal and LH-induced progesterone production. Studies with a general Dynamin inhibitor and siRNA knockdown of DRP1 showed that DRP1 is required for optimal LH-induced progesterone biosynthesis. Taken together, the findings place DRP1 as an important target downstream of PKA in steroidogenic luteal cells.
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Affiliation(s)
- Michele R Plewes
- Olson Center for Women's Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 983255 Nebraska Medical Center, Omaha, 68198-3255, NE, USA.,Nebraska Western Iowa Veterans Health Care System, Omaha, NE, USA
| | - Xiaoying Hou
- Olson Center for Women's Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 983255 Nebraska Medical Center, Omaha, 68198-3255, NE, USA
| | - Heather A Talbott
- Olson Center for Women's Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 983255 Nebraska Medical Center, Omaha, 68198-3255, NE, USA
| | - Pan Zhang
- Olson Center for Women's Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 983255 Nebraska Medical Center, Omaha, 68198-3255, NE, USA
| | - Jennifer R Wood
- Department of Animal Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - Andrea S Cupp
- Department of Animal Sciences, University of Nebraska-Lincoln, Lincoln, NE, USA
| | - John S Davis
- Olson Center for Women's Health, Department of Obstetrics and Gynecology, University of Nebraska Medical Center, 983255 Nebraska Medical Center, Omaha, 68198-3255, NE, USA.,Nebraska Western Iowa Veterans Health Care System, Omaha, NE, USA
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36
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Montecinos-Franjola F, Ramachandran R. Imaging Dynamin-Related Protein 1 (Drp1)-Mediated Mitochondrial Fission in Living Cells. Methods Mol Biol 2020; 2159:205-217. [PMID: 32529374 DOI: 10.1007/978-1-0716-0676-6_16] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Mitochondria form highly dynamic networks that continuously undergo fission and fusion. Dynamin-related protein 1 (Drp1), a key regulator of mitochondrial division, self-assembles into a helical polymer around pre-marked scission sites and generates the constriction force necessary to sever the organelle. Live-cell fluorescence imaging of Drp1 oligomerization dynamics and mitochondrial fission can provide unprecedented insights into the spatiotemporal relationship between these coupled processes. The high-resolution images provided by the laser scanning confocal microscope facilitate the observation of the finer details of mitochondrial structure as well as Drp1 polymer dynamics in real time. We provide a detailed description of the confocal imaging methods used to characterize mitochondrial dynamics in living cells with an emphasis on Drp1-mediated mitochondrial fission.
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Affiliation(s)
- Felipe Montecinos-Franjola
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
| | - Rajesh Ramachandran
- Department of Physiology & Biophysics, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
- Cleveland Center for Membrane and Structural Biology, Case Western Reserve University School of Medicine, Cleveland, OH, USA.
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37
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Zhukovsky MA, Filograna A, Luini A, Corda D, Valente C. Protein Amphipathic Helix Insertion: A Mechanism to Induce Membrane Fission. Front Cell Dev Biol 2019; 7:291. [PMID: 31921835 PMCID: PMC6914677 DOI: 10.3389/fcell.2019.00291] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 11/06/2019] [Indexed: 12/19/2022] Open
Abstract
One of the fundamental features of biomembranes is the ability to fuse or to separate. These processes called respectively membrane fusion and fission are central in the homeostasis of events such as those related to intracellular membrane traffic. Proteins that contain amphipathic helices (AHs) were suggested to mediate membrane fission via shallow insertion of these helices into the lipid bilayer. Here we analyze the AH-containing proteins that have been identified as essential for membrane fission and categorize them in few subfamilies, including small GTPases, Atg proteins, and proteins containing either the ENTH/ANTH- or the BAR-domain. AH-containing fission-inducing proteins may require cofactors such as additional proteins (e.g., lipid-modifying enzymes), or lipids (e.g., phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2], phosphatidic acid [PA], or cardiolipin). Both PA and cardiolipin possess a cone shape and a negative charge (-2) that favor the recruitment of the AHs of fission-inducing proteins. Instead, PtdIns(4,5)P2 is characterized by an high negative charge able to recruit basic residues of the AHs of fission-inducing proteins. Here we propose that the AHs of fission-inducing proteins contain sequence motifs that bind lipid cofactors; accordingly (K/R/H)(K/R/H)xx(K/R/H) is a PtdIns(4,5)P2-binding motif, (K/R)x6(F/Y) is a cardiolipin-binding motif, whereas KxK is a PA-binding motif. Following our analysis, we show that the AHs of many fission-inducing proteins possess five properties: (a) at least three basic residues on the hydrophilic side, (b) ability to oligomerize, (c) optimal (shallow) depth of insertion into the membrane, (d) positive cooperativity in membrane curvature generation, and (e) specific interaction with one of the lipids mentioned above. These lipid cofactors favor correct conformation, oligomeric state and optimal insertion depth. The most abundant lipid in a given organelle possessing high negative charge (more negative than -1) is usually the lipid cofactor in the fission event. Interestingly, naturally occurring mutations have been reported in AH-containing fission-inducing proteins and related to diseases such as centronuclear myopathy (amphiphysin 2), Charcot-Marie-Tooth disease (GDAP1), Parkinson's disease (α-synuclein). These findings add to the interest of the membrane fission process whose complete understanding will be instrumental for the elucidation of the pathogenesis of diseases involving mutations in the protein AHs.
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Affiliation(s)
- Mikhail A. Zhukovsky
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | | | | | - Daniela Corda
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Carmen Valente
- Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
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38
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Agrawal A, Ramachandran R. Exploring the links between lipid geometry and mitochondrial fission: Emerging concepts. Mitochondrion 2019; 49:305-313. [DOI: 10.1016/j.mito.2019.07.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 07/22/2019] [Accepted: 07/24/2019] [Indexed: 01/08/2023]
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Itoh K, Murata D, Kato T, Yamada T, Araki Y, Saito A, Adachi Y, Igarashi A, Li S, Pletnikov M, Huganir RL, Watanabe S, Kamiya A, Iijima M, Sesaki H. Brain-specific Drp1 regulates postsynaptic endocytosis and dendrite formation independently of mitochondrial division. eLife 2019; 8:44739. [PMID: 31603426 PMCID: PMC6824841 DOI: 10.7554/elife.44739] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 10/10/2019] [Indexed: 12/31/2022] Open
Abstract
Dynamin-related protein 1 (Drp1) divides mitochondria as a mechano-chemical GTPase. However, the function of Drp1 beyond mitochondrial division is largely unknown. Multiple Drp1 isoforms are produced through mRNA splicing. One such isoform, Drp1ABCD, contains all four alternative exons and is specifically expressed in the brain. Here, we studied the function of Drp1ABCD in mouse neurons in both culture and animal systems using isoform-specific knockdown by shRNA and isoform-specific knockout by CRISPR/Cas9. We found that the expression of Drp1ABCD is induced during postnatal brain development. Drp1ABCD is enriched in dendritic spines and regulates postsynaptic clathrin-mediated endocytosis by positioning the endocytic zone at the postsynaptic density, independently of mitochondrial division. Drp1ABCD loss promotes the formation of ectopic dendrites in neurons and enhanced sensorimotor gating behavior in mice. These data reveal that Drp1ABCD controls postsynaptic endocytosis, neuronal morphology and brain function.
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Affiliation(s)
- Kie Itoh
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Daisuke Murata
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Takashi Kato
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Tatsuya Yamada
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Yoichi Araki
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Atsushi Saito
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Yoshihiro Adachi
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Atsushi Igarashi
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Shuo Li
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Mikhail Pletnikov
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States.,Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Richard L Huganir
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Shigeki Watanabe
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Atsushi Kamiya
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Miho Iijima
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, United States
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40
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Eugenio-Pérez D, Briones-Herrera A, Martínez-Klimova E, Pedraza-Chaverri J. Divide et Impera: Drp1-mediated Mitochondrial Fission in Glioma Malignancy. THE YALE JOURNAL OF BIOLOGY AND MEDICINE 2019; 92:423-433. [PMID: 31543706 PMCID: PMC6747948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Mitochondria are pivotal organelles involved in vital cellular functions, including energy generation, reactive oxygen species and calcium signaling, as well as intermediate biosynthesis. They are dynamic organelles that adapt their shape, size, and distribution to changes in intracellular conditions, being able to divide, fuse, or move along the cell, processes known as mitochondrial dynamics. Mitochondrial dynamics are involved in cell division and migration, as well as maintenance of pluripotency in stem (non-differentiated) cells. Thus, its central role in carcinogenesis is not surprising. Particularly, mitochondrial dynamics have been found to be pivotal to the development of gliomas, a lethal group of tumors developed from glial cells, which are nervous system cells that provide support to neurons. Unfortunately, prognosis of glioma patients is poor, most of them do not survive more than five years after diagnosis. In this context, it is fundamental to understand the cellular mechanisms involved in this pathology, in order to develop an appropriate clinical approach. As previously mentioned, mitochondrial dynamics is central to glioma development, particularly, mitochondrial division (fission) and one of its central effectors, dynamin-related protein 1 (Drp1), have been observed to be enhanced in gliomas and involved in the maintenance of stem cells (which initiate and maintain the tumor), as well as in migration and invasiveness, being central to gliomagenesis. In this review, we discuss the findings on mitochondrial fission role in these processes, further, we analyze the potential use of Drp1 as a novel prognostic biomarker in glioma patients.
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Affiliation(s)
| | | | | | - José Pedraza-Chaverri
- To whom all correspondence should be addressed: José Pedraza-Chaverri, Facultad de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, Mexico City, 04510 Mexico;
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De Vecchis D, Brandner A, Baaden M, Cohen MM, Taly A. A Molecular Perspective on Mitochondrial Membrane Fusion: From the Key Players to Oligomerization and Tethering of Mitofusin. J Membr Biol 2019; 252:293-306. [PMID: 31485701 DOI: 10.1007/s00232-019-00089-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 08/14/2019] [Indexed: 12/29/2022]
Abstract
Mitochondria are dynamic organelles characterized by an ultrastructural organization which is essential in maintaining their quality control and ensuring functional efficiency. The complex mitochondrial network is the result of the two ongoing forces of fusion and fission of inner and outer membranes. Understanding the functional details of mitochondrial dynamics is physiologically relevant as perturbations of this delicate equilibrium have critical consequences and involved in several neurological disorders. Molecular actors involved in this process are large GTPases from the dynamin-related protein family. They catalyze nucleotide-dependent membrane remodeling and are widely conserved from bacteria to higher eukaryotes. Although structural characterization of different family members has contributed in understanding molecular mechanisms of mitochondrial dynamics in more detail, the complete structure of some members as well as the precise assembly of functional oligomers remains largely unknown. As increasing structural data become available, the domain modularity across the dynamin superfamily emerged as a foundation for transfering the knowledge towards less characterized members. In this review, we will first provide an overview of the main actors involved in mitochondrial dynamics. We then discuss recent example of computational methodologies for the study of mitofusin oligomers, and present how the usage of integrative modeling in conjunction with biochemical data can be an asset in progressing the still challenging field of membrane dynamics.
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Affiliation(s)
- Dario De Vecchis
- School of Medicine, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, LIGHT Building, Leeds, LS2 9JT, UK.
| | - Astrid Brandner
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 Rue Pierre et Marie Curie, 75005, Paris, France.,Institut de Biologie Physico-Chimique - Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Marc Baaden
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 Rue Pierre et Marie Curie, 75005, Paris, France.,Institut de Biologie Physico-Chimique - Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Mickael M Cohen
- Institut de Biologie Physico-Chimique - Fondation Edmond de Rothschild, PSL Research University, Paris, France.,Laboratoire de Biologie Cellulaire et Moléculaire des Eucaryotes, Sorbonne Université, CNRS, UMR 8226, Paris, France
| | - Antoine Taly
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, 13 Rue Pierre et Marie Curie, 75005, Paris, France. .,Institut de Biologie Physico-Chimique - Fondation Edmond de Rothschild, PSL Research University, Paris, France.
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Zhukovsky MA, Filograna A, Luini A, Corda D, Valente C. Phosphatidic acid in membrane rearrangements. FEBS Lett 2019; 593:2428-2451. [PMID: 31365767 DOI: 10.1002/1873-3468.13563] [Citation(s) in RCA: 106] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2019] [Revised: 07/25/2019] [Accepted: 07/26/2019] [Indexed: 12/16/2022]
Abstract
Phosphatidic acid (PA) is the simplest cellular glycerophospholipid characterized by unique biophysical properties: a small headgroup; negative charge; and a phosphomonoester group. Upon interaction with lysine or arginine, PA charge increases from -1 to -2 and this change stabilizes protein-lipid interactions. The biochemical properties of PA also allow interactions with lipids in several subcellular compartments. Based on this feature, PA is involved in the regulation and amplification of many cellular signalling pathways and functions, as well as in membrane rearrangements. Thereby, PA can influence membrane fusion and fission through four main mechanisms: it is a substrate for enzymes producing lipids (lysophosphatidic acid and diacylglycerol) that are involved in fission or fusion; it contributes to membrane rearrangements by generating negative membrane curvature; it interacts with proteins required for membrane fusion and fission; and it activates enzymes whose products are involved in membrane rearrangements. Here, we discuss the biophysical properties of PA in the context of the above four roles of PA in membrane fusion and fission.
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Affiliation(s)
- Mikhail A Zhukovsky
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Angela Filograna
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Alberto Luini
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Daniela Corda
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
| | - Carmen Valente
- Institute of Protein Biochemistry and Institute of Biochemistry and Cell Biology, National Research Council, Naples, Italy
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Zhukovsky MA, Filograna A, Luini A, Corda D, Valente C. The Structure and Function of Acylglycerophosphate Acyltransferase 4/ Lysophosphatidic Acid Acyltransferase Delta (AGPAT4/LPAATδ). Front Cell Dev Biol 2019; 7:147. [PMID: 31428612 PMCID: PMC6688108 DOI: 10.3389/fcell.2019.00147] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 07/16/2019] [Indexed: 12/27/2022] Open
Abstract
Lipid-modifying enzymes serve crucial roles in cellular processes such as signal transduction (producing lipid-derived second messengers), intracellular membrane transport (facilitating membrane remodeling needed for membrane fusion/fission), and protein clustering (organizing lipid domains as anchoring platforms). The lipid products crucial in these processes can derive from different metabolic pathways, thus it is essential to know the localization, substrate specificity, deriving products (and their function) of all lipid-modifying enzymes. Here we discuss an emerging family of these enzymes, the lysophosphatidic acid acyltransferases (LPAATs), also known as acylglycerophosphate acyltransferases (AGPATs), that produce phosphatidic acid (PA) having as substrates lysophosphatidic acid (LPA) and acyl-CoA. Eleven LPAAT/AGPAT enzymes have been identified in mice and humans based on sequence homologies, and their localization, specific substrates and functions explored. We focus on one member of the family, LPAATδ, a protein expressed mainly in brain and in muscle (though to a lesser extent in other tissues); while at the cellular level it is localized at the trans-Golgi network membranes and at the mitochondrial outer membranes. LPAATδ is a physiologically essential enzyme since mice knocked-out for Lpaatδ show severe dysfunctions including cognitive impairment, impaired force contractility and altered white adipose tissue. The LPAATδ physiological roles are related to the formation of its product PA. PA is a multifunctional lipid involved in cell signaling as well as in membrane remodeling. In particular, the LPAATδ-catalyzed conversion of LPA (inverted-cone-shaped lipid) to PA (cone-shaped lipid) is considered a mechanism of deformation of the bilayer that favors membrane fission. Indeed, LPAATδ is an essential component of the fission-inducing machinery driven by the protein BARS. In this process, a protein-tripartite complex (BARS/14-3-3γ/phosphoinositide kinase PI4KIIIβ) is recruited at the trans-Golgi network, at the sites where membrane fission is to occur; there, LPAATδ directly interacts with BARS and is activated by BARS. The resulting formation of PA is essential for membrane fission occurring at those spots. Also in mitochondria PA formation has been related to fusion/fission events. Since PA is formed by various enzymatic pathways in different cell compartments, the BARS-LPAATδ interaction indicates the relevance of lipid-modifying enzymes acting exactly where their products are needed (i.e., PA at the Golgi membranes).
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Affiliation(s)
- Mikhail A Zhukovsky
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Angela Filograna
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Alberto Luini
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Daniela Corda
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
| | - Carmen Valente
- Institute of Biochemistry and Cell Biology and Institute of Protein Biochemistry, National Research Council, Naples, Italy
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Brandner A, De Vecchis D, Baaden M, Cohen MM, Taly A. Physics-based oligomeric models of the yeast mitofusin Fzo1 at the molecular scale in the context of membrane docking. Mitochondrion 2019; 49:234-244. [PMID: 31306768 DOI: 10.1016/j.mito.2019.06.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Revised: 06/07/2019] [Accepted: 06/24/2019] [Indexed: 11/17/2022]
Abstract
Tethering and homotypic fusion of mitochondrial outer membranes is mediated by large GTPases of the dynamin-related proteins family called the mitofusins. The yeast mitofusin Fzo1 forms high molecular weight complexes and its assembly during membrane fusion likely involves the formation of high order complexes. Consistent with this possibility, mitofusins form oligomers in both cis (on the same lipid bilayer) and trans to mediate membrane attachment and fusion. Here, we utilize our recent Fzo1 model to investigate and discuss the formation of cis and trans mitofusin oligomers. We have built three distinct cis-assembly Fzo1 models that gave rise to three distinct trans-oligomeric models of mitofusin constructs. Each model involves two main components of mitofusin oligomerization: the GTPase and the trunk domains. The oligomeric models proposed in this study were further assessed for stability and dynamics in a membrane environment using a coarse-grained molecular dynamics (MD) simulation approach. A narrow opening 'head-to-head' cis-oligomerization (via the GTPase domain) followed by the antiparallel 'back-to-back' trans-associations (via the trunk domain) appears to be in agreement with all of the available experimental data. More broadly, this study opens new possibilities to start exploring cis and trans conformations for Fzo1 and mitofusins in general.
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Affiliation(s)
- Astrid Brandner
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, UPR 9080, 13 rue Pierre et Marie Curie, F-75005, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Dario De Vecchis
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, UPR 9080, 13 rue Pierre et Marie Curie, F-75005, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Marc Baaden
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, UPR 9080, 13 rue Pierre et Marie Curie, F-75005, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France
| | - Mickael M Cohen
- Laboratoire de Biologie Cellulaire et Moléculaire des Eucaryotes, Sorbonne Université, CNRS, UMR 8226, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France.
| | - Antoine Taly
- CNRS, Université de Paris, UPR 9080, Laboratoire de Biochimie Théorique, UPR 9080, 13 rue Pierre et Marie Curie, F-75005, Paris, France; Institut de Biologie Physico-Chimique-Fondation Edmond de Rothschild, PSL Research University, Paris, France.
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Huang NK, Lin CC, Lin YL, Huang CL, Chiou CT, Lee YC, Lee SY, Huang HT, Yang YC. Morphological control of mitochondria as the novel mechanism of Gastrodia elata in attenuating mutant huntingtin-induced protein aggregations. PHYTOMEDICINE : INTERNATIONAL JOURNAL OF PHYTOTHERAPY AND PHYTOPHARMACOLOGY 2019; 59:152756. [PMID: 31004885 DOI: 10.1016/j.phymed.2018.11.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/04/2018] [Accepted: 11/13/2018] [Indexed: 06/09/2023]
Abstract
BACKGROUND According to Compendium of Materia Medica, Gastrodia elata (GE) Blume as a top grade and frequently prescribed herbal medicine has been used in treating dizziness, headaches, and epilepsy, indicating a neuroprotective effect. Because GE is capable of suppressing a hyperactive liver and thus calming endogenous wind, and because Huntington's disease (HD) can be classified as a phenomenon of disturbed liver wind, it is suggested that GE might be beneficial in treating HD. However, although current studies support GE for the prevention of diverse neurodegenerations such as HD, its detailed mechanisms remain elusive. PURPOSE To investigate the molecular mechanism of GE in preventing HD by focusing on mitochondrial morphology, which is highly associated with HD etiology and thus proposed as a therapeutic target of neurodegenerations. STUDY DESIGN/METHODS The overexpression of the mutant huntingtin (mHTT) gene in rat pheochromocytoma (PC12) cells was used as an in vitro cell model of HD. A filter retardation assay was applied to measure protein aggregations during HTT expression. Cotransfection with mitochondrial fusion and fission genes was used to test their relationships with HTT aggregates by monitoring with a confocal laser scanning microscope and filter retardation assay. Western blot analysis was used to estimate protein expression under different drug treatments or cotransfections with other related genes. RESULTS The overexpression of mutant but not normal HTT genes significantly resulted in protein aggregations in PC12 cells. GE dose-dependently attenuated mHTT-induced protein aggregations and free radical formations. GE significantly reversed mHTT-induced mitochondrial fragmentation and dysregulation of mitochondrial fusion and fission molecules. The overexpression of mitochondrial fusion genes attenuated mHTT-induced protein aggregations. Further, Mdivi-1, a DRP1 fission molecule inhibitor, significantly reversed mHTT-induced protein aggregations and mitochondrial fragmentation. CONCLUSION GE attenuated mHTT aggregations through the control of mitochondrial fusion and the fission pathway.
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Affiliation(s)
- Nai-Kuei Huang
- National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan, ROC; Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan, ROC
| | - Chung-Chih Lin
- Brain Research Center, National Yang-Ming University, Taipei, Taiwan, ROC; Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan, ROC; Biophotonics Interdisciplinary Research Center, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Yun-Lian Lin
- School of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, College of Biopharmaceutical and Food Sciences, China Medical University, Taichung, Taiwan, ROC
| | - Chuen-Lin Huang
- Medical Research Center, Cardinal Tien Hospital, Hsintien, New Taipei City, Taiwan, ROC; Graduate Institute of Physiology & Department of Physiology and Biophysics, National Defense Medical Center, Taipei, Taiwan, ROC
| | - Chun-Tang Chiou
- National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan, ROC
| | - Yi-Chao Lee
- Program for Neural Regenerative Medicine, College of Medical Science and Technology, Taipei Medical University, Taipei, Taiwan, ROC
| | - Shu-Yi Lee
- Department of Life Sciences and Institute of Genome Sciences, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Hung-Tse Huang
- National Research Institute of Chinese Medicine, Ministry of Health and Welfare, Taipei, Taiwan, ROC
| | - Ying-Chen Yang
- Department of Biotechnology and Animal Science, National Ilan University, Ilan, Taiwan, ROC.
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RNA viruses promote activation of the NLRP3 inflammasome through cytopathogenic effect-induced potassium efflux. Cell Death Dis 2019; 10:346. [PMID: 31024004 PMCID: PMC6483999 DOI: 10.1038/s41419-019-1579-0] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 04/04/2019] [Accepted: 04/09/2019] [Indexed: 12/12/2022]
Abstract
Early detection of viruses by the innate immune system is crucial for host defense. The NLRP3 inflammasome, through activation of caspase-1, promotes the maturation of IL-1β and IL-18, which are critical for antiviral immunity and inflammatory response. However, the mechanism by which viruses activate this inflammasome is still debated. Here, we report that the replication of cytopathogenic RNA viruses such as vesicular stomatitis virus (VSV) or encephalomyocarditis virus (EMCV) induced a lytic cell death leading to potassium efflux, the common trigger of NLRP3 inflammasome activation. This lytic cell death was not prevented by a chemical or genetic inhibition of apoptosis, pyroptosis, or necroptosis but required the viral replication. Hence, the viruses that stimulated type I IFNs production after their sensing did not activate NLRP3 inflammasome due to an inhibition of their replication. In contrast, NLRP3 inflammasome activation induced by RNA virus infection was stimulated in IFNAR-deficient or MAVS-deficient cells consequently to an increased viral replication and ensuing lytic cell death. Therefore, in a context of inefficient IFN response, viral replication-induced lytic cell death activates of the NLRP3 inflammasome to fight against infection.
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Ultrastructure and dynamics of the actin-myosin II cytoskeleton during mitochondrial fission. Nat Cell Biol 2019; 21:603-613. [PMID: 30988424 PMCID: PMC6499663 DOI: 10.1038/s41556-019-0313-6] [Citation(s) in RCA: 90] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Accepted: 03/14/2019] [Indexed: 02/05/2023]
Abstract
Mitochondrial fission involves the preconstriction of an organelle followed by scission by dynamin-related protein Drp1. Preconstriction is facilitated by actin and non-muscle myosin II through a mechanism that remains unclear, largely due to the unknown cytoskeletal ultrastructure at mitochondrial constrictions. Here, using platinum replica electron microscopy, we show that mitochondria in cells are embedded in an interstitial cytoskeletal network that contains abundant unbranched actin filaments. Both spontaneous and induced mitochondrial constrictions typically associate with a criss-cross array of long actin filaments that comprise part of this interstitial network. Non-muscle myosin II is found adjacent to mitochondria but is not specifically enriched at the constriction sites. During ionomycin-induced mitochondrial fission, F-actin clouds colocalize with mitochondrial constriction sites, whereas dynamic myosin II clouds are present in the vicinity of constrictions. We propose that myosin II promotes mitochondrial constriction by inducing stochastic deformations of the interstitial actin network, which applies pressure on the mitochondrial surface and thus initiates curvature-sensing mechanisms that complete mitochondrial constriction.
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Yu R, Jin SB, Lendahl U, Nistér M, Zhao J. Human Fis1 regulates mitochondrial dynamics through inhibition of the fusion machinery. EMBO J 2019; 38:e99748. [PMID: 30842096 PMCID: PMC6463211 DOI: 10.15252/embj.201899748] [Citation(s) in RCA: 182] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 01/25/2019] [Accepted: 01/29/2019] [Indexed: 12/27/2022] Open
Abstract
Mitochondrial dynamics is important for life. At center stage for mitochondrial dynamics, the balance between mitochondrial fission and fusion is a set of dynamin-related GTPases that drive mitochondrial fission and fusion. Fission is executed by the GTPases Drp1 and Dyn2, whereas the GTPases Mfn1, Mfn2, and OPA1 promote fusion. Recruitment of Drp1 to mitochondria is a critical step in fission. In yeast, Fis1p recruits the Drp1 homolog Dnm1p to mitochondria through Mdv1p and Caf4p, but whether human Fis1 (hFis1) promotes fission through a similar mechanism as in yeast is not established. Here, we show that hFis1-mediated mitochondrial fragmentation occurs in the absence of Drp1 and Dyn2, suggesting that they are dispensable for hFis1 function. hFis1 instead binds to Mfn1, Mfn2, and OPA1 and inhibits their GTPase activity, thus blocking the fusion machinery. Consistent with this, disruption of the fusion machinery in Drp1-/- cells phenocopies the fragmentation phenotype induced by hFis1 overexpression. In sum, our data suggest a novel role for hFis1 as an inhibitor of the fusion machinery, revealing an important functional evolutionary divergence between yeast and mammalian Fis1 proteins.
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Affiliation(s)
- Rong Yu
- Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Shao-Bo Jin
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Urban Lendahl
- Department of Cell and Molecular Biology, Karolinska Institutet, Stockholm, Sweden
| | - Monica Nistér
- Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Jian Zhao
- Department of Oncology-Pathology, Karolinska Institutet, Karolinska University Hospital Solna, Stockholm, Sweden
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The dynamin-like protein Fzl promotes thylakoid fusion and resistance to light stress in Chlamydomonas reinhardtii. PLoS Genet 2019; 15:e1008047. [PMID: 30875368 PMCID: PMC6436760 DOI: 10.1371/journal.pgen.1008047] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Revised: 03/27/2019] [Accepted: 02/25/2019] [Indexed: 12/22/2022] Open
Abstract
Large GTPases of the Dynamin Related Proteins (DRP) family shape lipid bilayers through membrane fission or fusion processes. Despite the highly organized photosynthetic membranes of thylakoids, a single DRP is known to be targeted inside the chloroplast. Fzl from the land plant Arabidopsis thaliana is inserted in the inner envelope and thylakoid membranes to regulate their morphology. Fzl may promote the fusion of thylakoids but this remains to be proven. Moreover, the physiological requirement for fusing thylakoids is currently unknown. Here, we find that the unicellular microalga Chlamydomonas reinhardtii encodes an Fzl ortholog (CrFzl) that is localized in the chloroplast where it is soluble. To explore its function, the CRISPR/Cas9 technology was employed to generate multiple CrFzl knock out strains. Phenotypic analyzes revealed a specific requirement of CrFzl for survival upon light stress. Consistent with this, strong irradiance lead to increased photoinhibition of photosynthesis in mutant cells. Fluorescence and electron microscopy analysis demonstrated that upon exposure to high light, CrFzl mutants show defects in chloroplast morphology but also large cytosolic vacuoles in close contact with the plastid. We further observe that strong irradiance induces an increased recruitment of the DRP to thylakoid membranes. Most importantly, we show that CrFzl is required for the fusion of thylakoids during mating. Together, our results suggest that thylakoids fusion may be necessary for resistance to light stress. All eukaryotic cells are composed of compartments with defined functions. Among those, mitochondria generate the main source of energy in human and animal cells. Their capacity to generate and diffuse energy in the cell is regulated by fusion and fragmentation processes. Together with mitochondria that produce energy from oxygen, plant cells include an additional compartment called the chloroplast that produces energy from light. The machinery that converts light into energy is more precisely located inside the chloroplast within stacks of membranes called the thylakoids. Here, we elucidate the function of CrFzl, a previously uncharacterized protein encoded by the genome of the unicellular alga Chlamydomonas reinhardtii. Algal cells that do not contain CrFzl are impaired in their capacity to grow when they receive too much light and our results indicate that CrFzl promotes the fusion of thylakoids during mating. These results suggest that membrane fusion is an essential tool for energy production in stress conditions by living organisms.
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Abstract
The concept that mitochondria are highly dynamic is as widely accepted as it is untrue for a number of important contexts. Healthy mitochondria of the most energy-dependent and mitochondrial-rich mammalian organ, the heart, only rarely undergo fusion or fission and are seemingly static within cardiac myocytes. Here, we revisit mitochondrial dynamism with a fresh perspective developed from the recently discovered multifunctionality of mitochondrial fusion proteins and newly defined mechanisms for direct cross talk between mitochondrial dynamics, biogenesis, quality control, and trafficking pathways. Insights gained from comparing static mitochondrial biology in cardiac myocytes and dynamic mitochondrial biology in neurons are reviewed with the goal of understanding contextual fallacies of overly generalized characterizations of these essential and intriguing organelles.
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Affiliation(s)
- Gerald W. Dorn
- Center for Pharmacogenomics, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri 63110, USA
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