1
|
Xie Y, Liu X, Xie D, Zhang W, Zhao H, Guan H, Zhou PK. Voltage-dependent anion channel 1 mediates mitochondrial fission and glucose metabolic reprogramming in response to ionizing radiation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174246. [PMID: 38955266 DOI: 10.1016/j.scitotenv.2024.174246] [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: 02/04/2024] [Revised: 06/17/2024] [Accepted: 06/21/2024] [Indexed: 07/04/2024]
Abstract
The ionizing radiation (IR) represents a formidable challenge as an environmental factor to mitochondria, leading to disrupt cellular energy metabolism and posing health risks. Although the deleterious impacts of IR on mitochondrial function are recognized, the specific molecular targets remain incompletely elucidated. In this study, HeLa cells subjected to γ-rays exhibited concomitant oxidative stress, mitochondrial structural alterations, and diminished ATP production capacity. The γ-rays induced a dose-dependent induction of mitochondrial fission, simultaneously manifested by an elevated S616/S637 phosphorylation ratio of the dynamin-related protein 1 (DRP1) and a reduction in the expression of the mitochondrial fusion protein mitofusin 2 (MFN2). Knockdown of DRP1 effectively mitigated γ-rays-induced mitochondrial network damage, implying that DRP1 phosphorylation may act as an effector of radiation-induced mitochondrial damage. The mitochondrial outer membrane protein voltage-dependent anion channel 1 (VDAC1) was identified as a crucial player in IR-induced mitochondrial damage. The VDAC1 inhibitor 4,4'-diisothiocyanatostilbene-2,2'-disulfonic acid (DIDS), counteracts the excessive mitochondrial fission induced by γ-rays, consequently rebalancing the glycolytic and oxidative phosphorylation equilibrium. This metabolic shift was uncovered to enhance glycolytic capacity, thus fortifying cellular resilience and elevating the radiosensitivity of cancer cells. These findings elucidate the intricate regulatory mechanisms governing mitochondrial morphology under radiation response. It is anticipated that the development of targeted drugs directed against VDAC1 may hold promise in augmenting the sensitivity of tumor cells to radiotherapy and chemotherapy.
Collapse
Affiliation(s)
- Ying Xie
- Key Laboratory of Molecular Epidemiology of Hunan Province, School of Medicine, Hunan Normal University, Changsha 410081, PR China; Key Laboratory of Model Animals and Stem Cell Biology in Hunan Province, School of Medicine, Hunan Normal University, Changsha 410081, PR China
| | - Xiaochang Liu
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China
| | - Dafei Xie
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China
| | - Wen Zhang
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China
| | - Hongling Zhao
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China
| | - Hua Guan
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China.
| | - Ping-Kun Zhou
- Department of Radiation Biology, Beijing Key Laboratory for Radiobiology, Beijing Institute of Radiation Medicine, Beijing 100850, PR China.
| |
Collapse
|
2
|
Luo JS, Zhai WH, Ding LL, Zhang XJ, Han J, Ning JQ, Chen XM, Jiang WC, Yan RY, Chen MJ. MAMs and Mitochondrial Quality Control: Overview and Their Role in Alzheimer's Disease. Neurochem Res 2024; 49:2682-2698. [PMID: 39002091 DOI: 10.1007/s11064-024-04205-w] [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: 04/25/2024] [Revised: 06/20/2024] [Accepted: 07/02/2024] [Indexed: 07/15/2024]
Abstract
Alzheimer's disease (AD) represents the most widespread neurodegenerative disorder, distinguished by a gradual onset and slow progression, presenting a substantial challenge to global public health. The mitochondrial-associated membrane (MAMs) functions as a crucial center for signal transduction and material transport between mitochondria and the endoplasmic reticulum, playing a pivotal role in various pathological mechanisms of AD. The dysregulation of mitochondrial quality control systems is considered a fundamental factor in the development of AD, leading to mitochondrial dysfunction and subsequent neurodegenerative events. Recent studies have emphasized the role of MAMs in regulating mitochondrial quality control. This review will delve into the molecular mechanisms underlying the imbalance in mitochondrial quality control in AD and provide a comprehensive overview of the role of MAMs in regulating mitochondrial quality control.
Collapse
Affiliation(s)
- Jian-Sheng Luo
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Wen-Hu Zhai
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Ling-Ling Ding
- Department of Anesthesiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China.
| | - Xian-Jie Zhang
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Jia Han
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Jia-Qi Ning
- Department of Anesthesiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Xue-Meng Chen
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Wen-Cai Jiang
- Department of Anesthesiology, Deyang People's Hospital, Deyang, 618000, China
| | - Ru-Yu Yan
- Department of Anesthesiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| | - Meng-Jie Chen
- Department of Anesthesiology, Beijing Hospital of Traditional Chinese Medicine, Capital Medical University, Beijing, 100010, China
| |
Collapse
|
3
|
Dematteis G, Tapella L, Lim D. Probing the endoplasmic reticulum-mitochondria interaction in Alzheimer's disease: searching far and wide. Neural Regen Res 2024; 19:2103-2104. [PMID: 38488539 PMCID: PMC11034600 DOI: 10.4103/1673-5374.392880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Revised: 11/22/2023] [Accepted: 12/06/2023] [Indexed: 04/24/2024] Open
Affiliation(s)
- Giulia Dematteis
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Novara, Italy
| | - Laura Tapella
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Novara, Italy
| | - Dmitry Lim
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Novara, Italy
| |
Collapse
|
4
|
Song J, Li Y, Zhang Z, Gao X, Li S, Zhang J, Zhou M, Duan Y. Endoplasmic reticulum-mitochondrial encounter structure regulates the mitochondrial morphology, DON biosynthesis and toxisome formation in Fusarium graminearum. Microbiol Res 2024; 289:127892. [PMID: 39255584 DOI: 10.1016/j.micres.2024.127892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2024] [Revised: 08/28/2024] [Accepted: 08/31/2024] [Indexed: 09/12/2024]
Abstract
The endoplasmic reticulum-mitochondrial encounter structure (ERMES) complex is known to play crucial roles in various cellular processes. However, its functional significance in filamentous fungi, particularly its impact on deoxynivalenol (DON) biosynthesis in Fusarium graminearum, remains inadequately understood. In this study, we aimed to investigate the regulatory function of the ERMES complex in F. graminearum. Our findings indicate significant changes in mitochondrial morphology of ERMES mutants, accompanied by decreased ATP content and ergosterol production. Notably, the toxisome formation in the ERMES mutant ΔFgMDM10 was defective, resulting in a substantial reduction in DON biosynthesis. This suggests a pivotal role of ERMES in toxisome formation, as evidenced by the pronounced inhibition of toxisome formation when ERMES was disrupted by boscalid. Furthermore, ERMES deficiencies were shown to diminish the virulence of F. graminearum towards host plants significantly. In conclusion, our results suggest ERMES is an important regulator of mitochondrial morphology, DON biosynthesis, and toxisome formation in F. graminearum.
Collapse
Affiliation(s)
- Jichang Song
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Yige Li
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Ziyang Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Xinlong Gao
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Shengxue Li
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Jie Zhang
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China
| | - Mingguo Zhou
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing 210095, China
| | - Yabing Duan
- College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China; State & Local Joint Engineering Research Center of Green Pesticide Invention and Application, Nanjing Agricultural University, Nanjing 210095, China.
| |
Collapse
|
5
|
Li X, Gamuyao R, Wu ML, Cho WJ, King SV, Petersen R, Stabley DR, Lindow C, Climer LK, Shirinifard A, Ferrara F, Throm RE, Robinson CG, Zhou Y, Carisey AF, Tebo AG, Chang CL. A fluorogenic complementation tool kit for interrogating lipid droplet-organelle interaction. J Cell Biol 2024; 223:e202311126. [PMID: 38949658 PMCID: PMC11215687 DOI: 10.1083/jcb.202311126] [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: 11/22/2023] [Revised: 04/24/2024] [Accepted: 05/31/2024] [Indexed: 07/02/2024] Open
Abstract
Contact sites between lipid droplets and other organelles are essential for cellular lipid and energy homeostasis upon metabolic demands. Detection of these contact sites at the nanometer scale over time in living cells is challenging. We developed a tool kit for detecting contact sites based on fluorogen-activated bimolecular complementation at CONtact sites, FABCON, using a reversible, low-affinity split fluorescent protein, splitFAST. FABCON labels contact sites with minimal perturbation to organelle interaction. Via FABCON, we quantitatively demonstrated that endoplasmic reticulum (ER)- and mitochondria (mito)-lipid droplet contact sites are dynamic foci in distinct metabolic conditions, such as during lipid droplet biogenesis and consumption. An automated analysis pipeline further classified individual contact sites into distinct subgroups based on size, likely reflecting differential regulation and function. Moreover, FABCON is generalizable to visualize a repertoire of organelle contact sites including ER-mito. Altogether, FABCON reveals insights into the dynamic regulation of lipid droplet-organelle contact sites and generates new hypotheses for further mechanistical interrogation during metabolic regulation.
Collapse
Affiliation(s)
- Xiao Li
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Rico Gamuyao
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Ming-Lun Wu
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Woo Jung Cho
- Cell and Tissue Imaging Center, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Sharon V. King
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - R.A. Petersen
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Daniel R. Stabley
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Caleb Lindow
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Leslie K. Climer
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Abbas Shirinifard
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Francesca Ferrara
- Vector Production and Development Laboratory, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Robert E. Throm
- Vector Production and Development Laboratory, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Camenzind G. Robinson
- Cell and Tissue Imaging Center, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Yiwang Zhou
- Department of Biostatistics, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Alexandre F. Carisey
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| | - Alison G. Tebo
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, USA
| | - Chi-Lun Chang
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, USA
| |
Collapse
|
6
|
Sathyamurthy VH, Nagarajan Y, Parvathi VD. Mitochondria-Endoplasmic Reticulum Contact Sites (MERCS): A New Axis in Neuronal Degeneration and Regeneration. Mol Neurobiol 2024; 61:6528-6538. [PMID: 38321352 DOI: 10.1007/s12035-024-03971-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 01/20/2024] [Indexed: 02/08/2024]
Abstract
Mitochondria-Endoplasmic Reticulum Contact Sites (MERCS) are dynamic structures whose physiological interaction is vital to direct life and death of the cell. A bevy of tethering proteins, mitofusin-1/2 (Mfn-1/2), glucose-regulated protein-75 (Grp-75), voltage-dependent anion channel-1 (VDAC1), and dynamic-related protein-1 (Drp1), plays an integral role in establishing and regulating this intricate intracellular communication. Dysregulation of this interplay leads to various neurodegenerative disorders, like Alzheimer's disease (AD), Parkinson's disease (PD), stroke, traumatic brain injury (TBI), amyotrophic lateral sclerosis (ALS), and frontotemporal dementia (FTD). Although there is an absence of a well-defined molecular background that dictates the pathway of MERCS, adequate exploration has resulted in preliminary data that suggests its cardinal role in neuroregeneration. The juxtaposition of mitochondria and ER has a critical function in cell senescence, thus regulating regeneration. Axonal regeneration and brain tissue regeneration, using reactive astrocytes, are studied most extensively. Overexpression of Grp-75 promoted axonal regeneration post a nerve injury. Attempts have been made to exploit MERCS as potential therapeutic drug targets for enhancing neuroregeneration and impeding neurodegeneration. Novel strategies have been developed to aid the delivery of mitochondria into the neuronal cell body, which in turn establishes a network with the presiding ER resulting in contact site formation. The fascinating aspect of this mechanism is that despite the lack of inherent regenerative capacity in neurons, it can be induced by modifying MERCS.
Collapse
Affiliation(s)
- Vijaya Harini Sathyamurthy
- Department of Biomedical Sciences, Faculty of Biomedical Sciences and Technology, Sri Ramachandra Institute of Higher Education and Research, Porur, Chennai, 600116, India
| | - Yoghalakshmi Nagarajan
- Department of Biomedical Sciences, Faculty of Biomedical Sciences and Technology, Sri Ramachandra Institute of Higher Education and Research, Porur, Chennai, 600116, India
| | - Venkatachalam Deepa Parvathi
- Department of Biomedical Sciences, Faculty of Biomedical Sciences and Technology, Sri Ramachandra Institute of Higher Education and Research, Porur, Chennai, 600116, India.
| |
Collapse
|
7
|
Grepper D, Tabasso C, Zanou N, Aguettaz AK, Castro-Sepulveda M, Ziegler DV, Lagarrigue S, Arribat Y, Martinotti A, Ebrahimi A, Daraspe J, Fajas L, Amati F. BCL2L13 at endoplasmic reticulum-mitochondria contact sites regulates calcium homeostasis to maintain skeletal muscle function. iScience 2024; 27:110510. [PMID: 39175772 PMCID: PMC11340602 DOI: 10.1016/j.isci.2024.110510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 03/17/2024] [Accepted: 07/11/2024] [Indexed: 08/24/2024] Open
Abstract
The physical connection between mitochondria and endoplasmic reticulum (ER) is an essential signaling hub to ensure organelle and cellular functions. In skeletal muscle, ER-mitochondria calcium (Ca2+) signaling is crucial to maintain cellular homeostasis during physical activity. High expression of BCL2L13, a member of the BCL-2 family, was suggested as an adaptive response in endurance-trained human subjects. In adult zebrafish, we found that the loss of Bcl2l13 impairs skeletal muscle structure and function. Ca2+ signaling is altered in Bcl2l13 knockout animals and mitochondrial complexes activity is decreased. Organelle fractioning in mammalian cells shows BCL2L13 at mitochondria, ER, and mitochondria-associated membranes. ER-mitochondria contact sites number is not modified by BCL2L13 modulation, but knockdown of BCL2L13 in C2C12 cells changes cytosolic Ca2+ release and mitochondrial Ca2+ uptake. This suggests that BCL2L13 interaction with mitochondria and ER, and its role in Ca2+ signaling, contributes to proper skeletal muscle function.
Collapse
Affiliation(s)
- Dogan Grepper
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
| | - Cassandra Tabasso
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
| | - Nadège Zanou
- Institute of Sport Sciences, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Vaud 1015, Switzerland
| | - Axel K.F. Aguettaz
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
- Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital and University of Lausanne, Lausanne, Vaud 1011, Switzerland
| | - Mauricio Castro-Sepulveda
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
| | - Dorian V. Ziegler
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Vaud 1015, Switzerland
| | - Sylviane Lagarrigue
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
| | - Yoan Arribat
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
| | - Adrien Martinotti
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
- Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital and University of Lausanne, Lausanne, Vaud 1011, Switzerland
| | - Ammar Ebrahimi
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
- Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital and University of Lausanne, Lausanne, Vaud 1011, Switzerland
| | - Jean Daraspe
- Electron Microscopy Facility, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Vaud 1015, Switzerland
| | - Lluis Fajas
- Center for Integrative Genomics, Faculty of Biology and Medicine, University of Lausanne, Lausanne, Vaud 1015, Switzerland
| | - Francesca Amati
- Aging and Muscle Metabolism Lab, Department of Biomedical Sciences, Faculty of Biology and Medicine, University of Lausanne, Bugnon 7, Lausanne, Vaud 1005, Switzerland
- Service of Endocrinology, Diabetes and Metabolism, Lausanne University Hospital and University of Lausanne, Lausanne, Vaud 1011, Switzerland
| |
Collapse
|
8
|
Hinton A, Claypool SM, Neikirk K, Senoo N, Wanjalla CN, Kirabo A, Williams CR. Mitochondrial Structure and Function in Human Heart Failure. Circ Res 2024; 135:372-396. [PMID: 38963864 PMCID: PMC11225798 DOI: 10.1161/circresaha.124.323800] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/06/2024]
Abstract
Despite clinical and scientific advancements, heart failure is the major cause of morbidity and mortality worldwide. Both mitochondrial dysfunction and inflammation contribute to the development and progression of heart failure. Although inflammation is crucial to reparative healing following acute cardiomyocyte injury, chronic inflammation damages the heart, impairs function, and decreases cardiac output. Mitochondria, which comprise one third of cardiomyocyte volume, may prove a potential therapeutic target for heart failure. Known primarily for energy production, mitochondria are also involved in other processes including calcium homeostasis and the regulation of cellular apoptosis. Mitochondrial function is closely related to morphology, which alters through mitochondrial dynamics, thus ensuring that the energy needs of the cell are met. However, in heart failure, changes in substrate use lead to mitochondrial dysfunction and impaired myocyte function. This review discusses mitochondrial and cristae dynamics, including the role of the mitochondria contact site and cristae organizing system complex in mitochondrial ultrastructure changes. Additionally, this review covers the role of mitochondria-endoplasmic reticulum contact sites, mitochondrial communication via nanotunnels, and altered metabolite production during heart failure. We highlight these often-neglected factors and promising clinical mitochondrial targets for heart failure.
Collapse
Affiliation(s)
- Antentor Hinton
- Department of Molecular Physiology and Biophysics (A.H., K.N.), Vanderbilt University Medical Center, Nashville
| | - Steven M. Claypool
- Department of Physiology, Mitochondrial Phospholipid Research Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (S.M.C., N.S.)
| | - Kit Neikirk
- Department of Molecular Physiology and Biophysics (A.H., K.N.), Vanderbilt University Medical Center, Nashville
| | - Nanami Senoo
- Department of Physiology, Mitochondrial Phospholipid Research Center, Johns Hopkins University School of Medicine, Baltimore, Maryland (S.M.C., N.S.)
| | - Celestine N. Wanjalla
- Department of Medicine, Division of Clinical Pharmacology (C.N.W., A.K.), Vanderbilt University Medical Center, Nashville
| | - Annet Kirabo
- Department of Medicine, Division of Clinical Pharmacology (C.N.W., A.K.), Vanderbilt University Medical Center, Nashville
- Vanderbilt Center for Immunobiology (A.K.)
- Vanderbilt Institute for Infection, Immunology and Inflammation (A.K.)
- Vanderbilt Institute for Global Health (A.K.)
| | - Clintoria R. Williams
- Department of Neuroscience, Cell Biology and Physiology, Wright State University, Dayton, OH (C.R.W.)
| |
Collapse
|
9
|
Teixeira P, Galland R, Chevrollier A. Super-resolution microscopies, technological breakthrough to decipher mitochondrial structure and dynamic. Semin Cell Dev Biol 2024; 159-160:38-51. [PMID: 38310707 DOI: 10.1016/j.semcdb.2024.01.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 01/08/2024] [Accepted: 01/25/2024] [Indexed: 02/06/2024]
Abstract
Mitochondria are complex organelles with an outer membrane enveloping a second inner membrane that creates a vast matrix space partitioned by pockets or cristae that join the peripheral inner membrane with several thin junctions. Several micrometres long, mitochondria are generally close to 300 nm in diameter, with membrane layers separated by a few tens of nanometres. Ultrastructural data from electron microscopy revealed the structure of these mitochondria, while conventional optical microscopy revealed their extraordinary dynamics through fusion, fission, and migration processes but its limited resolution power restricted the possibility to go further. By overcoming the limits of light diffraction, Super-Resolution Microscopy (SRM) now offers the potential to establish the links between the ultrastructure and remodelling of mitochondrial membranes, leading to major advances in our understanding of mitochondria's structure-function. Here we review the contributions of SRM imaging to our understanding of the relationship between mitochondrial structure and function. What are the hopes for these new imaging approaches which are particularly important for mitochondrial pathologies?
Collapse
Affiliation(s)
- Pauline Teixeira
- Univ. Angers, INSERM, CNRS, MITOVASC, Equipe MITOLAB, SFR ICAT, F-49000 Angers, France
| | - Rémi Galland
- Univ. Bordeaux, CNRS, Interdisciplinary Institute for Neuroscience, IINS, UMR 5297, F-33000 Bordeaux, France
| | - Arnaud Chevrollier
- Univ. Angers, INSERM, CNRS, MITOVASC, Equipe MITOLAB, SFR ICAT, F-49000 Angers, France.
| |
Collapse
|
10
|
Zhang Z, Zhou H, Gu W, Wei Y, Mou S, Wang Y, Zhang J, Zhong Q. CGI1746 targets σ 1R to modulate ferroptosis through mitochondria-associated membranes. Nat Chem Biol 2024; 20:699-709. [PMID: 38212578 DOI: 10.1038/s41589-023-01512-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2021] [Accepted: 11/17/2023] [Indexed: 01/13/2024]
Abstract
Ferroptosis is iron-dependent oxidative cell death. Labile iron and polyunsaturated fatty acid (PUFA)-containing lipids are two critical factors for ferroptosis execution. Many processes regulating iron homeostasis and lipid synthesis are critically involved in ferroptosis. However, it remains unclear whether biological processes other than iron homeostasis and lipid synthesis are associated with ferroptosis. Using kinase inhibitor library screening, we discovered a small molecule named CGI1746 that potently blocks ferroptosis. Further studies demonstrate that CGI1746 acts through sigma-1 receptor (σ1R), a chaperone primarily located at mitochondria-associated membranes (MAMs), to inhibit ferroptosis. Suppression of σ1R protects mice from cisplatin-induced acute kidney injury hallmarked by ferroptosis. Mechanistically, CGI1746 treatment or genetic disruption of MAMs leads to defective Ca2+ transfer, mitochondrial reactive oxygen species (ROS) production and PUFA-containing triacylglycerol accumulation. Therefore, we propose a critical role for MAMs in ferroptosis execution.
Collapse
Affiliation(s)
- Zili Zhang
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Hong Zhou
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Wenjia Gu
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China
| | - Yuehan Wei
- Department of Nephrology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Shan Mou
- Department of Nephrology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Youjun Wang
- Beijing Key Laboratory of Gene Resource and Molecular Development, College of Life Sciences, Beijing Normal University, Beijing, China.
- Key Laboratory of Cell Proliferation and Regulation Biology, Ministry of Education, College of Life Sciences, Beijing Normal University, Beijing, China.
| | - Jing Zhang
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| | - Qing Zhong
- Key Laboratory of Cell Differentiation and Apoptosis of Chinese Ministry of Education, Department of Pathophysiology, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
| |
Collapse
|
11
|
Yu F, Courjaret R, Assaf L, Elmi A, Hammad A, Fisher M, Terasaki M, Machaca K. Mitochondria-ER contact sites expand during mitosis. iScience 2024; 27:109379. [PMID: 38510124 PMCID: PMC10951641 DOI: 10.1016/j.isci.2024.109379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 01/31/2024] [Accepted: 02/27/2024] [Indexed: 03/22/2024] Open
Abstract
Mitochondria-ER contact sites (MERCS) are involved in energy homeostasis, redox and Ca2+ signaling, and inflammation. MERCS are heavily studied; however, little is known about their regulation during mitosis. Here, we show that MERCS expand during mitosis in three cell types using various approaches, including transmission electron microscopy, serial EM coupled to 3D reconstruction, and a split GFP MERCS marker. We further show enhanced Ca2+ transfer between the ER and mitochondria using either direct Ca2+ measurements or by quantifying the activity of Ca2+-dependent mitochondrial dehydrogenases. Collectively, our results support a lengthening of MERCS in mitosis that is associated with improved Ca2+ coupling between the two organelles. This augmented Ca2+ coupling could be important to support the increased energy needs of the cell during mitosis.
Collapse
Affiliation(s)
- Fang Yu
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
| | - Raphael Courjaret
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
| | - Lama Assaf
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- College of Health and Life Science, Hamad bin Khalifa University, Doha, Qatar
| | - Asha Elmi
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- College of Health and Life Science, Hamad bin Khalifa University, Doha, Qatar
| | - Ayat Hammad
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- College of Health and Life Science, Hamad bin Khalifa University, Doha, Qatar
| | - Melanie Fisher
- Department of Cell Biology, UConn Health, 263 Farmington Ave, Farmington, CT 06030, USA
| | - Mark Terasaki
- Department of Cell Biology, UConn Health, 263 Farmington Ave, Farmington, CT 06030, USA
| | - Khaled Machaca
- Calcium Signaling Group, Research Department, Weill Cornell Medicine Qatar, Education City, Qatar Foundation, Doha, Qatar
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY, USA
| |
Collapse
|
12
|
Li M, Zhang Y, Yu G, Gu L, Zhu H, Feng S, Xiong X, Jian Z. Mitochondria-associated endoplasmic reticulum membranes tethering protein VAPB-PTPIP51 protects against ischemic stroke through inhibiting the activation of autophagy. CNS Neurosci Ther 2024; 30:e14707. [PMID: 38584329 PMCID: PMC10999572 DOI: 10.1111/cns.14707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/09/2024] [Accepted: 03/24/2024] [Indexed: 04/09/2024] Open
Abstract
AIMS Mitochondria-associated endoplasmic reticulum membranes (MAMs) serve as a crucial bridge connecting the endoplasmic reticulum (ER) and mitochondria within cells. Vesicle-associated membrane protein-associated protein B (VAPB) and protein tyrosine phosphatase interacting protein 51 (PTPIP51) are responsible for the formation and stability of MAMs, which have been implicated in the pathogenesis of various diseases. However, the role of MAMs in ischemic stroke (IS) remains unclear. We aimed to investigate the role of MAMs tethering protein VAPB-PTPIP51 in experimental cerebral ischemia. METHODS We simulated cerebral ischemia-reperfusion injury (CIRI) by using a mouse middle cerebral artery occlusion (MCAO) model. RESULTS We observed a decrease in VAPB-PTPIP51 expression in the brain tissue. Our findings suggested compromised MAMs after MCAO, as a decreased mitochondria-ER contact (MERC) coverage and an increased distance were observed through the transmission electron microscope (TEM). Upon VAPB or PTPIP51 knockdown, the damage to MAMs was exacerbated, accompanied by excessive autophagy activation and increased reactive oxygen species (ROS) production, resulting in an enlarged infarct area and exacerbated neurological deficits. Notably, we observed that this damage was concomitant with the inhibition of the PI3K/AKT/mTOR pathway and was successfully mitigated by the treatment with the PI3K activator. CONCLUSIONS Our findings suggest that the downregulation of VAPB-PTPIP51 expression after IS mediates structural damage to MAMs. This may exacerbate CIRI by inhibiting the PI3K pathway and activating autophagy, thus providing new therapeutic targets for IS.
Collapse
Affiliation(s)
- Mingyang Li
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Yonggang Zhang
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Guixiang Yu
- Department of OphthalmologyRenmin Hospital of Wuhan UniversityWuhanChina
| | - Lijuan Gu
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Hua Zhu
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Shi Feng
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Xiaoxing Xiong
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
- Central LaboratoryRenmin Hospital of Wuhan UniversityWuhanChina
| | - Zhihong Jian
- Department of NeurosurgeryRenmin Hospital of Wuhan UniversityWuhanChina
| |
Collapse
|
13
|
Ramazanov BR, Parchure A, Di Martino R, Kumar A, Chung M, Kim Y, Griesbeck O, Schwartz MA, Luini A, von Blume J. Calcium flow at ER-TGN contact sites facilitates secretory cargo export. Mol Biol Cell 2024; 35:ar50. [PMID: 38294859 PMCID: PMC11064664 DOI: 10.1091/mbc.e23-03-0099] [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: 05/01/2023] [Revised: 01/19/2024] [Accepted: 01/24/2024] [Indexed: 02/01/2024] Open
Abstract
Ca2+ influx into the trans-Golgi Network (TGN) promotes secretory cargo sorting by the Ca2+-ATPase SPCA1 and the luminal Ca2+ binding protein Cab45. Cab45 oligomerizes upon local Ca2+ influx, and Cab45 oligomers sequester and separate soluble secretory cargo from the bulk flow of proteins in the TGN. However, how this Ca2+ flux into the lumen of the TGN is achieved remains mysterious, as the cytosol has a nanomolar steady-state Ca2+ concentration. The TGN forms membrane contact sites (MCS) with the Endoplasmic Reticulum (ER), allowing protein-mediated exchange of molecular species such as lipids. Here, we show that the TGN export of secretory proteins requires the integrity of ER-TGN MCS and inositol 3 phosphate receptor (IP3R)-dependent Ca2+ fluxes in the MCS, suggesting Ca2+ transfer between these organelles. Using an MCS-targeted Ca2+ FRET sensor module, we measure the Ca2+ flow in these sites in real time. These data show that ER-TGN MCS facilitates the Ca2+ transfer required for Ca2+-dependent cargo sorting and export from the TGN, thus solving a fundamental question in cell biology.
Collapse
Affiliation(s)
- Bulat R. Ramazanov
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
| | - Anup Parchure
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
| | - Rosaria Di Martino
- Institute of Biochemistry and Cell Biology, National Research Council, Naples 80131, Italy
| | - Abhishek Kumar
- Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT 06510
| | - Minhwan Chung
- Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT 06510
| | - Yeongho Kim
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
| | - Oliver Griesbeck
- Max Planck Institute of Neurobiology, Martinsried 82152, Germany
| | - Martin A. Schwartz
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
- Yale Cardiovascular Research Center, Yale University School of Medicine, New Haven, CT 06510
- Department of Biomedical Engineering, Yale University, New Haven, CT 06511
| | - Alberto Luini
- Institute of Biochemistry and Cell Biology, National Research Council, Naples 80131, Italy
| | - Julia von Blume
- Department of Cell Biology, Yale University School of Medicine, New Haven, CT 06510
| |
Collapse
|
14
|
Germani S, Van Ho AT, Cherubini A, Varone E, Chernorudskiy A, Renna GM, Fumagalli S, Gobbi M, Lucchetti J, Bolis M, Guarrera L, Craparotta I, Rastelli G, Piccoli G, de Napoli C, Nogara L, Poggio E, Brini M, Cattaneo A, Bachi A, Simmen T, Calì T, Quijano-Roy S, Boncompagni S, Blaauw B, Ferreiro A, Zito E. SEPN1-related myopathy depends on the oxidoreductase ERO1A and is druggable with the chemical chaperone TUDCA. Cell Rep Med 2024; 5:101439. [PMID: 38402623 PMCID: PMC10982971 DOI: 10.1016/j.xcrm.2024.101439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 12/06/2023] [Accepted: 01/31/2024] [Indexed: 02/27/2024]
Abstract
Selenoprotein N (SEPN1) is a protein of the endoplasmic reticulum (ER) whose inherited defects originate SEPN1-related myopathy (SEPN1-RM). Here, we identify an interaction between SEPN1 and the ER-stress-induced oxidoreductase ERO1A. SEPN1 and ERO1A, both enriched in mitochondria-associated membranes (MAMs), are involved in the redox regulation of proteins. ERO1A depletion in SEPN1 knockout cells restores ER redox, re-equilibrates short-range MAMs, and rescues mitochondrial bioenergetics. ERO1A knockout in a mouse background of SEPN1 loss blunts ER stress and improves multiple MAM functions, including Ca2+ levels and bioenergetics, thus reversing diaphragmatic weakness. The treatment of SEPN1 knockout mice with the ER stress inhibitor tauroursodeoxycholic acid (TUDCA) mirrors the results of ERO1A loss. Importantly, muscle biopsies from patients with SEPN1-RM exhibit ERO1A overexpression, and TUDCA-treated SEPN1-RM patient-derived primary myoblasts show improvement in bioenergetics. These findings point to ERO1A as a biomarker and a viable target for intervention and to TUDCA as a pharmacological treatment for SEPN1-RM.
Collapse
Affiliation(s)
- Serena Germani
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy; Department of Molecular and Developmental Medicine, University of Siena, Siena, Italy
| | - Andrew Tri Van Ho
- Basic and Translational Myology Laboratory, Université Paris, BFA, UMR 8251, CNRS, 75013 Paris, France
| | | | - Ersilia Varone
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | | | | | | | - Marco Gobbi
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | - Jacopo Lucchetti
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | - Marco Bolis
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy; Bioinformatics Core Unit, Institute of Oncology Research (IOR), 6500 Bellinzona, Switzerland
| | - Luca Guarrera
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy
| | | | - Giorgia Rastelli
- CAST, Center for Advanced Studies and Technology & DNICS, Department of Neuroscience, Imaging and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, 66100 Chieti, Italy
| | - Giorgia Piccoli
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Cosimo de Napoli
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | - Leonardo Nogara
- Department of Biomedical Sciences, University of Padua, Padua, Italy; Department of Pharmaceutical Sciences, University of Padova, Padova, Italy
| | - Elena Poggio
- Department of Biology, University of Padova, Padova, Italy
| | - Marisa Brini
- Department of Pharmaceutical Sciences, University of Padova, Padova, Italy; Department of Biology, University of Padova, Padova, Italy; Study Center for Neurodegeneration (CESNE), University of Padova, Padova, Italy
| | | | - Angela Bachi
- IFOM-ETS AIRC Institute of Molecular Oncology, Milan, Italy
| | - Thomas Simmen
- Department of Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB, Canada
| | - Tito Calì
- Department of Biomedical Sciences, University of Padua, Padua, Italy; Study Center for Neurodegeneration (CESNE), University of Padova, Padova, Italy; Padova Neuroscience Center, University of Padova, Padova, Italy
| | - Susana Quijano-Roy
- APHP-Université Paris-Saclay, Reference Center for Neuromuscular Disorders Nord-Est-Ile de France, FILNEMUS, ERN-Euro-NMD, Creteil, France; Pediatric Neurology and ICU Department, DMU Santé Enfant Adolescent (SEA), Raymond Poincaré University Hospital, Garches, France
| | - Simona Boncompagni
- CAST, Center for Advanced Studies and Technology & DNICS, Department of Neuroscience, Imaging and Clinical Sciences, University G. D'Annunzio of Chieti-Pescara, 66100 Chieti, Italy
| | - Bert Blaauw
- Department of Biomedical Sciences, University of Padua, Padua, Italy; Venetian Institute of Molecular Medicine, Padova, Italy.
| | - Ana Ferreiro
- Basic and Translational Myology Laboratory, Université Paris, BFA, UMR 8251, CNRS, 75013 Paris, France; APHP, Reference Center for Neuromuscular Disorders Nord-Est-Ile de France, Neuromyology Department, Groupe Hospitalier Pitié-Salpêtrière, Paris, France.
| | - Ester Zito
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy; Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy.
| |
Collapse
|
15
|
Wilson EL, Yu Y, Leal NS, Woodward JA, Patikas N, Morris JL, Field SF, Plumbly W, Paupe V, Chowdhury SR, Antrobus R, Lindop GE, Adia YM, Loh SHY, Prudent J, Martins LM, Metzakopian E. Genome-wide CRISPR/Cas9 screen shows that loss of GET4 increases mitochondria-endoplasmic reticulum contact sites and is neuroprotective. Cell Death Dis 2024; 15:203. [PMID: 38467609 PMCID: PMC10928201 DOI: 10.1038/s41419-024-06568-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Revised: 02/13/2024] [Accepted: 02/19/2024] [Indexed: 03/13/2024]
Abstract
Organelles form membrane contact sites between each other, allowing for the transfer of molecules and signals. Mitochondria-endoplasmic reticulum (ER) contact sites (MERCS) are cellular subdomains characterized by close apposition of mitochondria and ER membranes. They have been implicated in many diseases, including neurodegenerative, metabolic, and cardiac diseases. Although MERCS have been extensively studied, much remains to be explored. To uncover novel regulators of MERCS, we conducted a genome-wide, flow cytometry-based screen using an engineered MERCS reporter cell line. We found 410 genes whose downregulation promotes MERCS and 230 genes whose downregulation decreases MERCS. From these, 29 genes were selected from each population for arrayed screening and 25 were validated from the high population and 13 from the low population. GET4 and BAG6 were highlighted as the top 2 genes that upon suppression increased MERCS from both the pooled and arrayed screens, and these were subjected to further investigation. Multiple microscopy analyses confirmed that loss of GET4 or BAG6 increased MERCS. GET4 and BAG6 were also observed to interact with the known MERCS proteins, inositol 1,4,5-trisphosphate receptors (IP3R) and glucose-regulated protein 75 (GRP75). In addition, we found that loss of GET4 increased mitochondrial calcium uptake upon ER-Ca2+ release and mitochondrial respiration. Finally, we show that loss of GET4 rescues motor ability, improves lifespan and prevents neurodegeneration in a Drosophila model of Alzheimer's disease (Aβ42Arc). Together, these results suggest that GET4 is involved in decreasing MERCS and that its loss is neuroprotective.
Collapse
Affiliation(s)
- Emma L Wilson
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Yizhou Yu
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Nuno S Leal
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - James A Woodward
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Nikolaos Patikas
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - Jordan L Morris
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Sarah F Field
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - William Plumbly
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK
| | - Vincent Paupe
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Suvagata R Chowdhury
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK
| | - Robin Antrobus
- Cambridge Institute for Medical Research, University of Cambridge, The Keith Peters Building, Cambridge Biomedical Campus, Hills Rd, Cambridge, CB2 0XY, UK
| | - Georgina E Lindop
- Cambridge Advanced Imaging Centre, University of Cambridge, Anatomy Building, Downing Site, Cambridge, CB2 3DY, UK
| | - Yusuf M Adia
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Samantha H Y Loh
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK
| | - Julien Prudent
- MRC Mitochondrial Biology Unit, University of Cambridge, The Keith Peters building, Cambridge Biomedical Campus, Cambridge, CB2 0XY, UK.
| | - L Miguel Martins
- MRC Toxicology Unit, University of Cambridge, Gleeson Building, Tennis Court Road, Cambridge, CB2 1QR, UK.
| | - Emmanouil Metzakopian
- UK Dementia Research Institute, University of Cambridge, Clifford Albutt building, Cambridge biomedical campus, Cambridge, CB2 0AH, UK.
- bit bio, The Dorothy Hodgkin Building, Babraham Research Campus, Cambridge, CB22 3FH, UK.
| |
Collapse
|
16
|
Yamano K, Kinefuchi H, Kojima W. Mitochondrial lipid dynamics regulated by MITOL-mediated ubiquitination. J Biochem 2024; 175:217-219. [PMID: 38156789 DOI: 10.1093/jb/mvad117] [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: 11/17/2023] [Accepted: 12/19/2023] [Indexed: 01/03/2024] Open
Abstract
Mitochondria-endoplasmic reticulum (ER) contact sites in mammals provide platforms for various reactions, such as calcium signaling, lipid metabolism, organelle dynamics and autophagy. To fulfill these tasks, a number of proteins assemble at the contact sites including MITOL/MARCHF5, a critical mitochondrial ubiquitin ligase. How MITOL regulates mitochondrial function from the contact site, however, has been largely unresolved. Recently, a new role for MITOL in the active transport of phosphatidic acid from the ER to mitochondria was reported. In this commentary, we briefly summarize our current understanding of mitochondria-ER contact sites and discuss the recently elucidated mechanism of MITOL fine-tuning phospholipid transfer activity through ubiquitination.
Collapse
Affiliation(s)
- Koji Yamano
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| | - Hiroki Kinefuchi
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
- Department of Biosciences, School of Science, Kitasato University, 1-15-1 Kitasato, Minami-ku, Sagamihara, Kanagawa 252-0373, Japan
| | - Waka Kojima
- Department of Biomolecular Pathogenesis, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8510, Japan
| |
Collapse
|
17
|
Sneyers F, Speelman-Rooms F, Verhelst SHL, Bootman MD, Bultynck G. Cellular effects of BAPTA: Are they only about Ca 2+ chelation? BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119589. [PMID: 37739271 DOI: 10.1016/j.bbamcr.2023.119589] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 09/06/2023] [Accepted: 09/10/2023] [Indexed: 09/24/2023]
Abstract
Intracellular Ca2+ signals play a vital role in a broad range of cell biological and physiological processes in all eukaryotic cell types. Dysregulation of Ca2+ signaling has been implicated in numerous human diseases. Over the past four decades, the understanding of how cells use Ca2+ as a messenger has flourished, largely because of the development of reporters that enable visualization of Ca2+ signals in different cellular compartments, and tools that can modulate cellular Ca2+ signaling. One such tool that is frequently used is BAPTA; a fast, high-affinity Ca2+-chelating molecule. By making use of a cell-permeable acetoxymethyl ester (AM) variant, BAPTA can be readily loaded into the cytosol of cells (referred to as BAPTAi), where it is trapped and able to buffer changes in cytosolic Ca2+. Due to the ease of loading of the AM version of BAPTA, this reagent has been used in hundreds of studies to probe the role of Ca2+ signaling in specific processes. As such, for decades, researchers have almost universally attributed changes in biological processes caused by BAPTAi to the involvement of Ca2+ signaling. However, BAPTAi has often been used without any form of control, and in many cases has neither been shown to be retained in cells for the duration of experiments nor to buffer any Ca2+ signals. Moreover, increasing evidence points to off-target cellular effects of BAPTA that are clearly not related to Ca2+ chelation. Here, we briefly introduce Ca2+ signaling and the history of Ca2+ chelators and fluorescent Ca2+ indicators. We highlight Ca2+-independent effects of BAPTAi on a broad range of molecular targets and describe some of BAPTAi's impacts on cell functions that occur independently of its Ca2+-chelating properties. Finally, we propose strategies for determining whether Ca2+ chelation, the binding of other metal ions, or off-target interactions with cell components are responsible for BAPTAi's effect on a particular process and suggest some future research directions.
Collapse
Affiliation(s)
- Flore Sneyers
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium
| | - Femke Speelman-Rooms
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium; KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Chemical Biology, Herestraat 49 box 901b, B-3000 Leuven, Belgium
| | - Steven H L Verhelst
- KU Leuven, Department of Cellular and Molecular Medicine, Laboratory of Chemical Biology, Herestraat 49 box 901b, B-3000 Leuven, Belgium
| | - Martin D Bootman
- The Open University, Cancer Research Group, School of Life, Health and Chemical Sciences, Milton Keynes, UK
| | - Geert Bultynck
- KU Leuven, Lab. Molecular & Cellular Signaling, Dep. Cellular & Molecular Medicine, Campus Gasthuisberg O/N-I bus 802, Herestraat 49, B-3000 Leuven, Belgium.
| |
Collapse
|
18
|
An G, Park J, Song J, Hong T, Song G, Lim W. Relevance of the endoplasmic reticulum-mitochondria axis in cancer diagnosis and therapy. Exp Mol Med 2024; 56:40-50. [PMID: 38172597 PMCID: PMC10834980 DOI: 10.1038/s12276-023-01137-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 01/05/2024] Open
Abstract
Dynamic interactions between organelles are responsible for a variety of intercellular functions, and the endoplasmic reticulum (ER)-mitochondrial axis is recognized as a representative interorganelle system. Several studies have confirmed that most proteins in the physically tethered sites between the ER and mitochondria, called mitochondria-associated ER membranes (MAMs), are vital for intracellular physiology. MAM proteins are involved in the regulation of calcium homeostasis, lipid metabolism, and mitochondrial dynamics and are associated with processes related to intracellular stress conditions, such as oxidative stress and unfolded protein responses. Accumulating evidence has shown that, owing to their extensive involvement in cellular homeostasis, alterations in the ER-mitochondrial axis are one of the etiological factors of tumors. An in-depth understanding of MAM proteins and their impact on cell physiology, particularly in cancers, may help elucidate their potential as diagnostic and therapeutic targets for cancers. For example, the modulation of MAM proteins is utilized not only to target diverse intracellular signaling pathways within cancer cells but also to increase the sensitivity of cancer cells to anticancer reagents and regulate immune cell activities. Therefore, the current review summarizes and discusses recent advances in research on the functional roles of MAM proteins and their characteristics in cancers from a diagnostic perspective. Additionally, this review provides insights into diverse therapeutic strategies that target MAM proteins in various cancer types.
Collapse
Affiliation(s)
- Garam An
- Institute of Animal Molecular Biotechnology, Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Junho Park
- Institute of Animal Molecular Biotechnology, Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Jisoo Song
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Taeyeon Hong
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea
| | - Gwonhwa Song
- Institute of Animal Molecular Biotechnology, Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea.
| | - Whasun Lim
- Department of Biological Sciences, College of Science, Sungkyunkwan University, Suwon, 16419, Republic of Korea.
| |
Collapse
|
19
|
Skalka GL, Tsakovska M, Murphy DJ. Kinase signalling adaptation supports dysfunctional mitochondria in disease. Front Mol Biosci 2024; 11:1354682. [PMID: 38434478 PMCID: PMC10906720 DOI: 10.3389/fmolb.2024.1354682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Accepted: 01/15/2024] [Indexed: 03/05/2024] Open
Abstract
Mitochondria form a critical control nexus which are essential for maintaining correct tissue homeostasis. An increasing number of studies have identified dysregulation of mitochondria as a driver in cancer. However, which pathways support and promote this adapted mitochondrial function? A key hallmark of cancer is perturbation of kinase signalling pathways. These pathways include mitogen activated protein kinases (MAPK), lipid secondary messenger networks, cyclic-AMP-activated (cAMP)/AMP-activated kinases (AMPK), and Ca2+/calmodulin-dependent protein kinase (CaMK) networks. These signalling pathways have multiple substrates which support initiation and persistence of cancer. Many of these are involved in the regulation of mitochondrial morphology, mitochondrial apoptosis, mitochondrial calcium homeostasis, mitochondrial associated membranes (MAMs), and retrograde ROS signalling. This review will aim to both explore how kinase signalling integrates with these critical mitochondrial pathways and highlight how these systems can be usurped to support the development of disease. In addition, we will identify areas which require further investigation to fully understand the complexities of these regulatory interactions. Overall, this review will emphasize how studying the interaction between kinase signalling and mitochondria improves our understanding of mitochondrial homeostasis and can yield novel therapeutic targets to treat disease.
Collapse
Affiliation(s)
- George L. Skalka
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Mina Tsakovska
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Daniel J. Murphy
- School of Cancer Sciences, University of Glasgow, Glasgow, United Kingdom
- CRUK Scotland Institute, Glasgow, United Kingdom
| |
Collapse
|
20
|
Veluthakal R, Esparza D, Hoolachan JM, Balakrishnan R, Ahn M, Oh E, Jayasena CS, Thurmond DC. Mitochondrial Dysfunction, Oxidative Stress, and Inter-Organ Miscommunications in T2D Progression. Int J Mol Sci 2024; 25:1504. [PMID: 38338783 PMCID: PMC10855860 DOI: 10.3390/ijms25031504] [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: 12/22/2023] [Revised: 01/15/2024] [Accepted: 01/23/2024] [Indexed: 02/12/2024] Open
Abstract
Type 2 diabetes (T2D) is a heterogenous disease, and conventionally, peripheral insulin resistance (IR) was thought to precede islet β-cell dysfunction, promoting progression from prediabetes to T2D. New evidence suggests that T2D-lean individuals experience early β-cell dysfunction without significant IR. Regardless of the primary event (i.e., IR vs. β-cell dysfunction) that contributes to dysglycemia, significant early-onset oxidative damage and mitochondrial dysfunction in multiple metabolic tissues may be a driver of T2D onset and progression. Oxidative stress, defined as the generation of reactive oxygen species (ROS), is mediated by hyperglycemia alone or in combination with lipids. Physiological oxidative stress promotes inter-tissue communication, while pathological oxidative stress promotes inter-tissue mis-communication, and new evidence suggests that this is mediated via extracellular vesicles (EVs), including mitochondria containing EVs. Under metabolic-related stress conditions, EV-mediated cross-talk between β-cells and skeletal muscle likely trigger mitochondrial anomalies leading to prediabetes and T2D. This article reviews the underlying molecular mechanisms in ROS-related pathogenesis of prediabetes, including mitophagy and mitochondrial dynamics due to oxidative stress. Further, this review will describe the potential of various therapeutic avenues for attenuating oxidative damage, reversing prediabetes and preventing progression to T2D.
Collapse
Affiliation(s)
- Rajakrishnan Veluthakal
- Department of Molecular and Cellular Endocrinology, Arthur Riggs Diabetes & Metabolism Research Institute, City of Hope Beckman Research Institute, 1500 E. Duarte Rd, Duarte, CA 91010, USA; (D.E.); (J.M.H.); (R.B.); (M.A.); (E.O.); (C.S.J.)
| | | | | | | | | | | | | | - Debbie C. Thurmond
- Department of Molecular and Cellular Endocrinology, Arthur Riggs Diabetes & Metabolism Research Institute, City of Hope Beckman Research Institute, 1500 E. Duarte Rd, Duarte, CA 91010, USA; (D.E.); (J.M.H.); (R.B.); (M.A.); (E.O.); (C.S.J.)
| |
Collapse
|
21
|
Voeltz GK, Sawyer EM, Hajnóczky G, Prinz WA. Making the connection: How membrane contact sites have changed our view of organelle biology. Cell 2024; 187:257-270. [PMID: 38242082 DOI: 10.1016/j.cell.2023.11.040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 11/13/2023] [Accepted: 11/29/2023] [Indexed: 01/21/2024]
Abstract
The view of organelles and how they operate together has changed dramatically over the last two decades. The textbook view of organelles was that they operated largely independently and were connected by vesicular trafficking and the diffusion of signals through the cytoplasm. We now know that all organelles make functional close contacts with one another, often called membrane contact sites. The study of these sites has moved to center stage in cell biology as it has become clear that they play critical roles in healthy and developing cells and during cell stress and disease states. Contact sites have important roles in intracellular signaling, lipid metabolism, motor-protein-mediated membrane dynamics, organelle division, and organelle biogenesis. Here, we summarize the major conceptual changes that have occurred in cell biology as we have come to appreciate how contact sites integrate the activities of organelles.
Collapse
Affiliation(s)
- G K Voeltz
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
| | - E M Sawyer
- Department of Molecular, Cellular, and Developmental Biology, University of Colorado, Boulder, Boulder, CO 80309, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - G Hajnóczky
- MitoCare Center, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA 19107, USA
| | - W A Prinz
- Department of Cell Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
| |
Collapse
|
22
|
Lee HR, Choi SH, Lee SH. Differential involvement of mitochondria in post-tetanic potentiation at intracortical excitatory synapses of the medial prefrontal cortex. Cereb Cortex 2024; 34:bhad476. [PMID: 38061690 DOI: 10.1093/cercor/bhad476] [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: 10/12/2023] [Revised: 11/20/2022] [Accepted: 11/18/2023] [Indexed: 01/19/2024] Open
Abstract
Post-tetanic Ca2+ release from mitochondria produces presynaptic residual calcium, which contributes to post-tetanic potentiation. The loss of mitochondria-dependent post-tetanic potentiation is one of the earliest signs of Alzheimer's model mice. Post-tetanic potentiation at intracortical synapses of medial prefrontal cortex has been implicated in working memory. Although mitochondrial contribution to post-tetanic potentiation differs depending on synapse types, it is unknown which synapse types express mitochondria-dependent post-tetanic potentiation in the medial prefrontal cortex. We studied expression of mitochondria-dependent post-tetanic potentiation at different intracortical synapses of the rat medial prefrontal cortex. Post-tetanic potentiation occurred only at intracortical synapses onto layer 5 corticopontine cells from commissural cells and L2/3 pyramidal neurons. Among post-tetanic potentiation-expressing synapses, L2/3-corticopontine synapses in the prelimbic cortex were unique in that post-tetanic potentiation depends on mitochondria because post-tetanic potentiation at corresponding synapse types in other cortical areas was independent of mitochondria. Supporting mitochondria-dependent post-tetanic potentiation at L2/3-to-corticopontine synapses, mitochondria-dependent residual calcium at the axon terminals of L2/3 pyramidal neurons was significantly larger than that at commissural and corticopontine cells. Moreover, post-tetanic potentiation at L2/3-corticopontine synapses, but not at commissural-corticopontine synapses, was impaired in the young adult Alzheimer's model mice. These results would provide a knowledge base for comprehending synaptic mechanisms that underlies the initial clinical signs of neurodegenerative disorders.
Collapse
Affiliation(s)
- Hyoung-Ro Lee
- Department of Physiology, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
- Department of Brain and Cognitive Science, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Sung Hoon Choi
- Department of Physiology, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
- Department of Brain and Cognitive Science, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| | - Suk-Ho Lee
- Department of Physiology, College of Medicine, Seoul National University, Seoul 03080, Republic of Korea
- Department of Brain and Cognitive Science, College of Natural Science, Seoul National University, Seoul 08826, Republic of Korea
| |
Collapse
|
23
|
Csordás G, Weaver D, Várnai P, Hajnóczky G. Supralinear Dependence of the IP 3 Receptor-to-Mitochondria Local Ca 2+ Transfer on the Endoplasmic Reticulum Ca 2+ Loading. CONTACT (THOUSAND OAKS (VENTURA COUNTY, CALIF.)) 2024; 7:25152564241229273. [PMID: 38362008 PMCID: PMC10868505 DOI: 10.1177/25152564241229273] [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] [Received: 12/04/2022] [Revised: 12/31/2023] [Accepted: 01/12/2024] [Indexed: 02/17/2024]
Abstract
Calcium signal propagation from endoplasmic reticulum (ER) to mitochondria regulates a multitude of mitochondrial and cell functions, including oxidative ATP production and cell fate decisions. Ca2+ transfer is optimal at the ER-mitochondrial contacts, where inositol 1,4,5-trisphosphate (IP3) receptors (IP3R) can locally expose the mitochondrial Ca2+ uniporter (mtCU) to high [Ca2+] nanodomains. The Ca2+ loading state of the ER (Ca2 + ER) can vary broadly in physiological and pathological scenarios, however, the correlation between Ca2 + ER and the local Ca2+ transfer is unclear. Here, we studied IP3-induced Ca2+ transfer to mitochondria at different Ca2 + ER in intact and permeabilized RBL-2H3 cells via fluorescence measurements of cytoplasmic [Ca2+] ([Ca2+]c) and mitochondrial matrix [Ca2+] ([Ca2+]m). Preincubation of intact cells in high versus low extracellular [Ca2+] caused disproportionally greater increase in [Ca2+]m than [Ca2+]c responses to IP3-mobilizing agonist. Increasing Ca2 + ER by small Ca2+ boluses in suspensions of permeabilized cells supralinearly enhanced the mitochondrial Ca2+ uptake from IP3-induced Ca2+ release. The IP3-induced local [Ca2+] spikes exposing the mitochondrial surface measured using a genetically targeted sensor appeared to linearly correlate with Ca2 + ER, indicating that amplification happened in the mitochondria. Indeed, overexpression of an EF-hand deficient mutant of the mtCU gatekeeper MICU1 reduced the cooperativity of mitochondrial Ca2+ uptake. Interestingly, the IP3-induced [Ca2+]m signal plateaued at high Ca2 + ER, indicating activation of a matrix Ca2+ binding/chelating species. Mitochondria thus seem to maintain a "working [Ca2+]m range" via a low-affinity and high-capacity buffer species, and the ER loading steeply enhances the IP3R-linked [Ca2+]m signals in this working range.
Collapse
Affiliation(s)
- György Csordás
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - David Weaver
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Péter Várnai
- Department of Physiology, Semmelweis Medical University, Budapest, Hungary
| | - György Hajnóczky
- MitoCare Center for Mitochondrial Imaging Research and Diagnostics, Department of Pathology, Anatomy and Cell Biology, Thomas Jefferson University, Philadelphia, PA, USA
| |
Collapse
|
24
|
Area-Gomez E, Schon EA. Towards a Unitary Hypothesis of Alzheimer's Disease Pathogenesis. J Alzheimers Dis 2024; 98:1243-1275. [PMID: 38578892 DOI: 10.3233/jad-231318] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2024]
Abstract
The "amyloid cascade" hypothesis of Alzheimer's disease (AD) pathogenesis invokes the accumulation in the brain of plaques (containing the amyloid-β protein precursor [AβPP] cleavage product amyloid-β [Aβ]) and tangles (containing hyperphosphorylated tau) as drivers of pathogenesis. However, the poor track record of clinical trials based on this hypothesis suggests that the accumulation of these peptides is not the only cause of AD. Here, an alternative hypothesis is proposed in which the AβPP cleavage product C99, not Aβ, is the main culprit, via its role as a regulator of cholesterol metabolism. C99, which is a cholesterol sensor, promotes the formation of mitochondria-associated endoplasmic reticulum (ER) membranes (MAM), a cholesterol-rich lipid raft-like subdomain of the ER that communicates, both physically and biochemically, with mitochondria. We propose that in early-onset AD (EOAD), MAM-localized C99 is elevated above normal levels, resulting in increased transport of cholesterol from the plasma membrane to membranes of intracellular organelles, such as ER/endosomes, thereby upregulating MAM function and driving pathology. By the same token, late-onset AD (LOAD) is triggered by any genetic variant that increases the accumulation of intracellular cholesterol that, in turn, boosts the levels of C99 and again upregulates MAM function. Thus, the functional cause of AD is upregulated MAM function that, in turn, causes the hallmark disease phenotypes, including the plaques and tangles. Accordingly, the MAM hypothesis invokes two key interrelated elements, C99 and cholesterol, that converge at the MAM to drive AD pathogenesis. From this perspective, AD is, at bottom, a lipid disorder.
Collapse
Affiliation(s)
- Estela Area-Gomez
- Department of Neurology, Columbia University, New York, NY, USA
- Centro de Investigaciones Biológicas "Margarita Salas", Spanish National Research Council, Madrid, Spain
| | - Eric A Schon
- Department of Neurology, Columbia University, New York, NY, USA
- Department of Genetics and Development>, Columbia University, New York, NY, USA
| |
Collapse
|
25
|
Cardoen B, Vandevoorde KR, Gao G, Ortiz-Silva M, Alan P, Liu W, Tiliakou E, Vogl AW, Hamarneh G, Nabi IR. Membrane contact site detection (MCS-DETECT) reveals dual control of rough mitochondria-ER contacts. J Cell Biol 2024; 223:e202206109. [PMID: 37948126 PMCID: PMC10638097 DOI: 10.1083/jcb.202206109] [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: 06/23/2022] [Revised: 09/20/2022] [Accepted: 10/23/2023] [Indexed: 11/12/2023] Open
Abstract
Identification and morphological analysis of mitochondria-ER contacts (MERCs) by fluorescent microscopy is limited by subpixel resolution interorganelle distances. Here, the membrane contact site (MCS) detection algorithm, MCS-DETECT, reconstructs subpixel resolution MERCs from 3D super-resolution image volumes. MCS-DETECT shows that elongated ribosome-studded riboMERCs, present in HT-1080 but not COS-7 cells, are morphologically distinct from smaller smooth contacts and larger contacts induced by mitochondria-ER linker expression in COS-7 cells. RiboMERC formation is associated with increased mitochondrial potential, reduced in Gp78 knockout HT-1080 cells and induced by Gp78 ubiquitin ligase activity in COS-7 and HeLa cells. Knockdown of riboMERC tether RRBP1 eliminates riboMERCs in both wild-type and Gp78 knockout HT-1080 cells. By MCS-DETECT, Gp78-dependent riboMERCs present complex tubular shapes that intercalate between and contact multiple mitochondria. MCS-DETECT of 3D whole-cell super-resolution image volumes, therefore, identifies novel dual control of tubular riboMERCs, whose formation is dependent on RRBP1 and size modulated by Gp78 E3 ubiquitin ligase activity.
Collapse
Affiliation(s)
- Ben Cardoen
- School of Computing Science, Simon Fraser University, Burnaby, Canada
| | - Kurt R. Vandevoorde
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Guang Gao
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Milene Ortiz-Silva
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Parsa Alan
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - William Liu
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Ellie Tiliakou
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - A. Wayne Vogl
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Ghassan Hamarneh
- School of Computing Science, Simon Fraser University, Burnaby, Canada
| | - Ivan R. Nabi
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
- School of Biomedical Engineering, University of British Columbia, Vancouver, Canada
| |
Collapse
|
26
|
Rostamzadeh F, Najafipour H, Aminizadeh S, Jafari E. Therapeutic effects of the combination of moderate-intensity endurance training and MitoQ supplementation in rats with isoproterenol-induced myocardial injury: The role of mitochondrial fusion, fission, and mitophagy. Biomed Pharmacother 2024; 170:116020. [PMID: 38147733 DOI: 10.1016/j.biopha.2023.116020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2023] [Revised: 12/06/2023] [Accepted: 12/14/2023] [Indexed: 12/28/2023] Open
Abstract
INTRODUCTION Mitochondrial dysfunction causes myocardial disease. This study investigated the effects of MitoQ alone and in combination with moderate-intensity endurance training (EX) on cardiac function and content and mRNA expression of several proteins involved in mitochondrial quality control in isoproterenol (ISO)-induced heart injuries METHODS: Seven groups of CTL, ISO, ISO-EX, ISO-MitoQ-125, ISO-MitoQ-250, ISO-EX+MitoQ-125, and ISO-EX+MitoQ-250 were assigned. Rats were trained on a treadmill, and the MitoQ groups received MitoQ in drinking water for 8 weeks, starting one week after the induction of heart injury. Arterial pressure and cardiac function indices, mRNA expression, protein content, oxidant and antioxidant markers, fibrosis, and histopathological changes were assessed by physiograph, Real-Time PCR, immunofluorescence, calorimetry, Masson's trichrome, and H&E staining, respectively. RESULTS The impacts of MitoQ-125, EX+MitoQ-125, and EX+MitoQ-250 on arterial pressure and left ventricular systolic pressure were higher than MitoQ-250 or EX alone. ± dp/dt max were higher in ISO-EX+MitoQ-125 and ISO-EX+MitoQ-250 than ISO-MitoQ-125 and ISO-MitoQ-250 groups, respectively. Histopathological scores and fibrosis decreased in ISO-EX, ISO-MitoQ-125, ISO-EX+MitoQ-125, and ISO-EX+MitoQ-250 groups. The restoration of MFN2, PINK-1, and FIS-1 changes was higher in ISO-EX+MitoQ-125 and ISO-EX+MitoQ-250 than ISO-EX, ISO-MitoQ-125 and ISO-MitoQ-250 groups. The expression of MFN2 and PINK-1 was lower in ISO-MitoQ-125 and ISO-EX+MitoQ-125 than ISO and CTL groups. The expression of FIS-1 in ISO-EX and ISO-EX+MitoQ-250 increased compared to CTL and ISO groups. MDA decreased in ISO-MitoQ-125 and ISO-EX+MitoQ-125 groups. CONCLUSION Exercise and MitoQ combination have additive effects on cardiac function by modulating cardiac mitochondria quality. This study provided a possible therapy to treat heart injuries.
Collapse
Affiliation(s)
- Farzaneh Rostamzadeh
- Physiology Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Hamid Najafipour
- Cardiovascular Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran
| | - Soheil Aminizadeh
- Endocrinology and Metabolism Research Center, Institute of Basic and Clinical Physiology Sciences, and Department of Physiology and Pharmacology, Afzalipour School of Medicine, Kerman University of Medical Sciences, Kerman, Iran.
| | - Elham Jafari
- Pathology and Stem Cell Research Center, Kerman University of Medical Sciences, Kerman, Iran
| |
Collapse
|
27
|
Qiao L, Dou X, Song X, Chang J, Yi H, Xu C. Targeting mitochondria with antioxidant nutrients for the prevention and treatment of postweaning diarrhea in piglets. ANIMAL NUTRITION (ZHONGGUO XU MU SHOU YI XUE HUI) 2023; 15:275-287. [PMID: 38033610 PMCID: PMC10685042 DOI: 10.1016/j.aninu.2023.09.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 09/27/2023] [Accepted: 09/27/2023] [Indexed: 12/02/2023]
Abstract
Post-weaning diarrhea (PWD) in piglets poses a significant challenge and presents a grave threat to the global swine industry, resulting in considerable financial losses and compromising the welfare of animals. PWD is commonly associated with gut homeostatic imbalance, including oxidative stress, excessive inflammation, and microbiota dysbiosis. Antibiotic use has historically been a common initiative to combat PWD, but concerns about the development of antibiotic resistance have led to increased interest in alternative strategies. Mitochondria are key players in maintaining cellular homeostasis, and their dysfunction is intricately linked to the onset and progression of PWD. Accumulating evidence suggests that targeting mitochondrial function using antioxidant nutrients, such as vitamins, minerals and polyphenolic compounds, may represent a promising approach for preventing and treating PWD. Moreover, nutrients based on antioxidant strategies have been shown to improve mitochondrial function, restore intestinal redox balance, and reduce oxidative damage, which is a key driver of PWD. The present review begins with an overview of the potential interplay between mitochondria and gut homeostasis in the pathogenesis of PWD in piglets. Subsequently, alternative strategies to prevent and treat PWD using antioxidant nutrients to target mitochondria are described and discussed. Ultimately, we delve into potential limitations and suggest future research directions in this field for further advancement. Overall, targeting mitochondria using antioxidant nutrients may be a promising approach to combat PWD and provides a potential nutrition intervention strategy for regulating gut homeostasis of weaned piglets.
Collapse
Affiliation(s)
- Lei Qiao
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| | - Xina Dou
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| | - Xiaofan Song
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| | - Jiajing Chang
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| | - Hongbo Yi
- State Key Laboratory of Livestock and Poultry Breeding, Ministry of Agriculture Key Laboratory of Animal Nutrition and Feed Science in South China, Guangdong Provincial Key Laboratory of Animal Breeding and Nutrition, Institute of Animal Science of Guangdong Academy of Agricultural Sciences, Guangzhou, Guangdong, 510640, China
| | - Chunlan Xu
- School of Life Sciences, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China
| |
Collapse
|
28
|
Ray MN, Kiyofuji M, Ozono M, Kogure K. Vitamin E succinate mediated apoptosis by juxtaposing endoplasmic reticulum and mitochondria. Biochim Biophys Acta Gen Subj 2023; 1867:130485. [PMID: 37838355 DOI: 10.1016/j.bbagen.2023.130485] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 10/03/2023] [Accepted: 10/04/2023] [Indexed: 10/16/2023]
Abstract
Vitamin E succinate (VES) is an esterified form of natural α-tocopherol, has turned out to be novel anticancer agent. However, its anticancer mechanisms have not been illustrated. Previously, we reported VES mediated Ca2+ release from the endoplasmic reticulum (ER) causes mitochondrial Ca2+ overload, leading to mitochondrial depolarization and apoptosis. Here, we elucidated the mechanism of VES-induced Ca2+ transfer from ER to mitochondria by investigating the role of VES in ER-mitochondria contact formation. Transmission electron microscopic observation confirms VES mediated ER-mitochondria contact while fluorescence microscopic analysis revealed that VES increased mitochondria-associated ER membrane (MAM) formation. Pre-treatment with the inositol 1,4,5-triphosphate receptor (IP3R) antagonist 2-aminoethyl diphenylborinate (2-APB) decreased VES-induced MAM formation, suggesting the involvement of VES-induced Ca2+ efflux from ER in MAM formation. The ER IP3R receptor is known to interact with voltage-dependent anion channels (VDAC) via the chaperone glucose-regulated protein 75 kDa (GRP75) to bring ER and mitochondria nearby. Although we revealed that VES treatment does not affect GRP75 protein level, it increases GRP75 localization in the MAM. In addition, the inhibition of Ca2+ release from ER by 2-APB decreases GRP75 localization in the MAM, suggesting the possibility of Ca2+-induced conformational change of GRP75 that promotes formation of the IP3R-GRP75-VDAC complex and thereby encourages MAM formation. This study identifies the mechanism of VES-induced enhanced Ca2+ transfer from ER to mitochondria, which causes mitochondrial Ca2+ overload leading to apoptosis.
Collapse
Affiliation(s)
- Manobendro Nath Ray
- Department of Pharmaceutical Health Chemistry, Graduate School of Pharmaceutical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Michiko Kiyofuji
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Mizune Ozono
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan
| | - Kentaro Kogure
- Graduate School of Biomedical Sciences, Tokushima University, 1-78-1 Shomachi, Tokushima 770-8505, Japan.
| |
Collapse
|
29
|
Li X, Gamuyao R, Wu ML, Cho WJ, Kurtz NB, King SV, Petersen R, Stabley DR, Lindow C, Climer L, Shirinifard A, Ferrara F, Throm RE, Robinson CG, Carisey A, Tebo AG, Chang CL. A fluorogenic complementation tool kit for interrogating lipid droplet-organelle interaction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.11.29.569289. [PMID: 38076863 PMCID: PMC10705429 DOI: 10.1101/2023.11.29.569289] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
Contact sites between lipid droplets and other organelles are essential for cellular lipid and energy homeostasis. Detection of these contact sites at nanometer scale over time in living cells is challenging. Here, we developed a tool kit for detecting contact sites based on Fluorogen-Activated Bimolecular complementation at CONtact sites, FABCON, using a reversible, low affinity split fluorescent protein, splitFAST. FABCON labels contact sites with minimal perturbation to organelle interaction. Via FABCON, we quantitatively demonstrated that endoplasmic reticulum (ER)- and mitochondria (mito)-lipid droplet contact sites are dynamic foci in distinct metabolic conditions, such as during lipid droplet biogenesis and consumption. An automated analysis pipeline further classified individual contact sites into distinct subgroups based on size, likely reflecting differential regulation and function. Moreover, FABCON is generalizable to visualize a repertoire of organelle contact sites including ER-mito. Altogether, FABCON reveals insights into the dynamic regulation of lipid droplet-organelle contact sites and generates new hypotheses for further mechanistical interrogation during metabolic switch.
Collapse
Affiliation(s)
- Xiao Li
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Rico Gamuyao
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Ming-Lun Wu
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Woo Jung Cho
- Cell and Tissue Imaging Center, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Nathan B. Kurtz
- Cell and Tissue Imaging Center, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Sharon V. King
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - R.A. Petersen
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Daniel R. Stabley
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Caleb Lindow
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Leslie Climer
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Abbas Shirinifard
- Department of Developmental Neurobiology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Francesca Ferrara
- Vector Production and Development Laboratory, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Robert E. Throm
- Vector Production and Development Laboratory, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Camenzind G. Robinson
- Cell and Tissue Imaging Center, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Alex Carisey
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| | - Alison G. Tebo
- Janelia Research Campus, Howard Hughes Medical Institute, Ashburn, VA, United States
| | - Chi-Lun Chang
- Department of Cell and Molecular Biology, St. Jude Children’s Research Hospital, Memphis, TN, United States
| |
Collapse
|
30
|
Haynes V, Giulivi C. Calcium-Dependent Interaction of Nitric Oxide Synthase with Cytochrome c Oxidase: Implications for Brain Bioenergetics. Brain Sci 2023; 13:1534. [PMID: 38002494 PMCID: PMC10669843 DOI: 10.3390/brainsci13111534] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 10/24/2023] [Accepted: 10/27/2023] [Indexed: 11/26/2023] Open
Abstract
Targeted nitric oxide production is relevant for maintaining cellular energy production, protecting against oxidative stress, regulating cell death, and promoting neuroprotection. This study aimed to characterize the putative interaction of nitric-oxide synthase with mitochondrial proteins. The primary finding of this study is that cytochrome c oxidase (CCO) subunit IV (CCOIV) is associated directly with NOS in brain mitochondria when calcium ions are present. The matrix side of CCOIV binds to the N-terminus of NOS, supported by the abrogation of the binding by antibodies towards the N-terminus of NOS. Evidence supporting the interaction between CCOIV and NOS was provided by the coimmunoprecipitation of NOS from detergent-solubilized whole rat brain mitochondria with antibodies to CCOIV and the coimmunoprecipitation of CCOIV from crude brain NOS preparations using antibodies to NOS. The CCOIV domain that interacts with NOS was identified using a series of overlapping peptides derived from the primary sequence of CCOIV. As calcium ions not only activate NOS, but also facilitate the docking of NOS to CCOIV, this study points to a dynamic mechanism of controlling the bioenergetics by calcium changes, thereby adapting bioenergetics to cellular demands.
Collapse
Affiliation(s)
- Virginia Haynes
- School of Veterinary Medicine, Department Molecular Biosciences, University of California Davis, Davis, CA 95616, USA
| | - Cecilia Giulivi
- School of Veterinary Medicine, Department Molecular Biosciences, University of California Davis, Davis, CA 95616, USA
- Medical Investigation of Neurodevelopmental Disorders (MIND) Institute UCDH, University of California Davis, Sacramento, CA 95817, USA
| |
Collapse
|
31
|
Yepuri G, Ramirez LM, Theophall GG, Reverdatto SV, Quadri N, Hasan SN, Bu L, Thiagarajan D, Wilson R, Díez RL, Gugger PF, Mangar K, Narula N, Katz SD, Zhou B, Li H, Stotland AB, Gottlieb RA, Schmidt AM, Shekhtman A, Ramasamy R. DIAPH1-MFN2 interaction regulates mitochondria-SR/ER contact and modulates ischemic/hypoxic stress. Nat Commun 2023; 14:6900. [PMID: 37903764 PMCID: PMC10616211 DOI: 10.1038/s41467-023-42521-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Accepted: 10/13/2023] [Indexed: 11/01/2023] Open
Abstract
Inter-organelle contact and communication between mitochondria and sarco/endoplasmic reticulum (SR/ER) maintain cellular homeostasis and are profoundly disturbed during tissue ischemia. We tested the hypothesis that the formin Diaphanous-1 (DIAPH1), which regulates actin dynamics, signal transduction and metabolic functions, contributes to these processes. We demonstrate that DIAPH1 interacts directly with Mitofusin-2 (MFN2) to shorten mitochondria-SR/ER distance, thereby enhancing mitochondria-ER contact in cells including cardiomyocytes, endothelial cells and macrophages. Solution structure studies affirm the interaction between the Diaphanous Inhibitory Domain and the cytosolic GTPase domain of MFN2. In male rodent and human cardiomyocytes, DIAPH1-MFN2 interaction regulates mitochondrial turnover, mitophagy, and oxidative stress. Introduction of synthetic linker construct, which shorten the mitochondria-SR/ER distance, mitigated the molecular and functional benefits of DIAPH1 silencing in ischemia. This work establishes fundamental roles for DIAPH1-MFN2 interaction in the regulation of mitochondria-SR/ER contact networks. We propose that targeting pathways that regulate DIAPH1-MFN2 interactions may facilitate recovery from tissue ischemia.
Collapse
Affiliation(s)
- Gautham Yepuri
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Lisa M Ramirez
- Department of Chemistry, University of Albany, State University of New York, Albany, NY, 12222, USA
| | - Gregory G Theophall
- Department of Chemistry, University of Albany, State University of New York, Albany, NY, 12222, USA
| | - Sergei V Reverdatto
- Department of Chemistry, University of Albany, State University of New York, Albany, NY, 12222, USA
| | - Nosirudeen Quadri
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Syed Nurul Hasan
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Lei Bu
- Department of Medicine, Leon H. Charney Division of Cardiology, NYU Grossman School of Medicine, New York, NY, 10016, USA
| | - Devi Thiagarajan
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Robin Wilson
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Raquel López Díez
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Paul F Gugger
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Kaamashri Mangar
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Navneet Narula
- Department of Pathology, NYU Grossman School of Medicine, New York, NY, 10016, USA
| | - Stuart D Katz
- Department of Medicine, Leon H. Charney Division of Cardiology, NYU Grossman School of Medicine, New York, NY, 10016, USA
| | - Boyan Zhou
- Department of Population Health, NYU Grossman School of Medicine, New York, NY, 10016, USA
| | - Huilin Li
- Department of Population Health, NYU Grossman School of Medicine, New York, NY, 10016, USA
| | - Aleksandr B Stotland
- Department of Cardiology, Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Roberta A Gottlieb
- Department of Biomedical Sciences, Smidt Heart Institute, Cedars-Sinai Medical Center, Los Angeles, CA, 90048, USA
| | - Ann Marie Schmidt
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA
| | - Alexander Shekhtman
- Department of Chemistry, University of Albany, State University of New York, Albany, NY, 12222, USA
| | - Ravichandran Ramasamy
- Diabetes Research Program, Division of Endocrinology, Diabetes and Metabolism, Department of Medicine, NYU Grossman School of Medicine, New York, New York, 10016, USA.
| |
Collapse
|
32
|
Sarhadi TR, Panse JS, Nagotu S. Mind the gap: Methods to study membrane contact sites. Exp Cell Res 2023; 431:113756. [PMID: 37633408 DOI: 10.1016/j.yexcr.2023.113756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2023] [Revised: 08/11/2023] [Accepted: 08/13/2023] [Indexed: 08/28/2023]
Abstract
Organelles are dynamic entities whose functions are essential for the optimum functioning of cells. It is now known that the juxtaposition of organellar membranes is essential for the exchange of metabolites and their communication. These functional apposition sites are termed membrane contact sites. Dynamic membrane contact sites between various sub-cellular structures such as mitochondria, endoplasmic reticulum, peroxisomes, Golgi apparatus, lysosomes, lipid droplets, plasma membrane, endosomes, etc. have been reported in various model systems. The burgeoning area of research on membrane contact sites has witnessed several manuscripts in recent years that identified the contact sites and components involved. Several methods have been developed to identify, measure and analyze the membrane contact sites. In this manuscript, we aim to discuss important methods developed to date that are used to study membrane contact sites.
Collapse
Affiliation(s)
- Tanveera Rounaque Sarhadi
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Janhavee Shirish Panse
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India
| | - Shirisha Nagotu
- Organelle Biology and Cellular Ageing Lab, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, 781039, Assam, India.
| |
Collapse
|
33
|
Harper CS, Casler JC, Lackner LL. Temporal control of contact site formation reveals a relationship between mitochondrial division and Num1-mediated mitochondrial tethering. Mol Biol Cell 2023; 34:ar108. [PMID: 37585290 PMCID: PMC10559308 DOI: 10.1091/mbc.e23-05-0168] [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: 05/15/2023] [Revised: 07/17/2023] [Accepted: 08/09/2023] [Indexed: 08/18/2023] Open
Abstract
Mitochondrial division is critical for maintenance of mitochondrial morphology and cellular homeostasis. Previous studies have suggested that the mitochondria-ER-cortex anchor (MECA), a tripartite membrane contact site between mitochondria, the ER, and the plasma membrane, is involved in mitochondrial division. However, its role is poorly understood. We developed a system to control MECA formation and depletion, which allowed us to investigate the relationship between MECA-mediated contact sites and mitochondrial division. Num1 is the protein that mediates mitochondria-ER-plasma membrane tethering at MECA sites. Using both rapamycin-inducible dimerization and auxin-inducible degradation components coupled with Num1, we developed systems to temporally control the formation and depletion of the native contact site. Additionally, we designed a regulatable Num1-independant mitochondria-PM tether. We found that mitochondria-PM tethering alone is not sufficient to rescue mitochondrial division and that a specific feature of Num1-mediated tethering is required. This study demonstrates the utility of systems that regulate contact-site formation and depletion in studying the biological functions of membrane contact sites.
Collapse
Affiliation(s)
- Clare S. Harper
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208
| | - Jason C. Casler
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208
| | - Laura L. Lackner
- Department of Molecular Biosciences, Northwestern University, Evanston, IL, 60208
| |
Collapse
|
34
|
Grossmann D, Malburg N, Glaß H, Weeren V, Sondermann V, Pfeiffer JF, Petters J, Lukas J, Seibler P, Klein C, Grünewald A, Hermann A. Mitochondria-Endoplasmic Reticulum Contact Sites Dynamics and Calcium Homeostasis Are Differentially Disrupted in PINK1-PD or PRKN-PD Neurons. Mov Disord 2023; 38:1822-1836. [PMID: 37449534 DOI: 10.1002/mds.29525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 06/16/2023] [Indexed: 07/18/2023] Open
Abstract
BACKGROUND It is generally believed that the pathogenesis of PINK1/parkin-related Parkinson's disease (PD) is due to a disturbance in mitochondrial quality control. However, recent studies have found that PINK1 and Parkin play a significant role in mitochondrial calcium homeostasis and are involved in the regulation of mitochondria-endoplasmic reticulum contact sites (MERCSs). OBJECTIVE The aim of our study was to perform an in-depth analysis of the role of MERCSs and impaired calcium homeostasis in PINK1/Parkin-linked PD. METHODS In our study, we used induced pluripotent stem cell-derived dopaminergic neurons from patients with PD with loss-of-function mutations in PINK1 or PRKN. We employed a split-GFP-based contact site sensor in combination with the calcium-sensitive dye Rhod-2 AM and applied Airyscan live-cell super-resolution microscopy to determine how MERCSs are involved in the regulation of mitochondrial calcium homeostasis. RESULTS Our results showed that thapsigargin-induced calcium stress leads to an increase of the abundance of narrow MERCSs in wild-type neurons. Intriguingly, calcium levels at the MERCSs remained stable, whereas the increased net calcium influx resulted in elevated mitochondrial calcium levels. However, PINK1-PD or PRKN-PD neurons showed an increased abundance of MERCSs at baseline, accompanied by an inability to further increase MERCSs upon thapsigargin-induced calcium stress. Consequently, calcium distribution at MERCSs and within mitochondria was disrupted. CONCLUSIONS Our results demonstrated how the endoplasmic reticulum and mitochondria work together to cope with calcium stress in wild-type neurons. In addition, our results suggests that PRKN deficiency affects the dynamics and composition of MERCSs differently from PINK1 deficiency, resulting in differentially affected calcium homeostasis. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Collapse
Affiliation(s)
- Dajana Grossmann
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Nina Malburg
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Hannes Glaß
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Veronika Weeren
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Verena Sondermann
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Julia F Pfeiffer
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Janine Petters
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Jan Lukas
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
- Center for Transdisciplinary Neurosciences Rostock, University Medical Center Rostock, University of Rostock, Rostock, Germany
| | - Philip Seibler
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Christine Klein
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
| | - Anne Grünewald
- Institute of Neurogenetics, University of Lübeck, Lübeck, Germany
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Belvaux, Luxembourg
| | - Andreas Hermann
- Translational Neurodegeneration Section "Albrecht Kossel," Department of Neurology, University Medical Center Rostock, University of Rostock, Rostock, Germany
- Center for Transdisciplinary Neurosciences Rostock, University Medical Center Rostock, University of Rostock, Rostock, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen Rostock/Greifswald, Rostock, Germany
| |
Collapse
|
35
|
Tessier N, Ducrozet M, Dia M, Badawi S, Chouabe C, Crola Da Silva C, Ovize M, Bidaux G, Van Coppenolle F, Ducreux S. TRPV1 Channels Are New Players in the Reticulum-Mitochondria Ca 2+ Coupling in a Rat Cardiomyoblast Cell Line. Cells 2023; 12:2322. [PMID: 37759544 PMCID: PMC10529771 DOI: 10.3390/cells12182322] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 09/18/2023] [Accepted: 09/20/2023] [Indexed: 09/29/2023] Open
Abstract
The Ca2+ release in microdomains formed by intercompartmental contacts, such as mitochondria-associated endoplasmic reticulum membranes (MAMs), encodes a signal that contributes to Ca2+ homeostasis and cell fate control. However, the composition and function of MAMs remain to be fully defined. Here, we focused on the transient receptor potential vanilloid 1 (TRPV1), a Ca2+-permeable ion channel and a polymodal nociceptor. We found TRPV1 channels in the reticular membrane, including some at MAMs, in a rat cardiomyoblast cell line (SV40-transformed H9c2) by Western blotting, immunostaining, cell fractionation, and proximity ligation assay. We used chemical and genetic probes to perform Ca2+ imaging in four cellular compartments: the endoplasmic reticulum (ER), cytoplasm, mitochondrial matrix, and mitochondrial surface. Our results showed that the ER Ca2+ released through TRPV1 channels is detected at the mitochondrial outer membrane and transferred to the mitochondria. Finally, we observed that prolonged TRPV1 modulation for 30 min alters the intracellular Ca2+ equilibrium and influences the MAM structure or the hypoxia/reoxygenation-induced cell death. Thus, our study provides the first evidence that TRPV1 channels contribute to MAM Ca2+ exchanges.
Collapse
Affiliation(s)
- Nolwenn Tessier
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Mallory Ducrozet
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Maya Dia
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Sally Badawi
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Christophe Chouabe
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Claire Crola Da Silva
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Michel Ovize
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
- Hospices Civils de Lyon, Hôpital Louis Pradel, Services d’Explorations Fonctionnelles Cardiovasculaires et CIC de Lyon, 69394 Lyon, France
| | - Gabriel Bidaux
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Fabien Van Coppenolle
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| | - Sylvie Ducreux
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, 69500 Bron, France; (N.T.); (M.D.); (M.D.); (S.B.); (C.C.); (C.C.D.S.); (M.O.); (G.B.); (F.V.C.)
| |
Collapse
|
36
|
Ying Z, Ye N, Ma Q, Chen F, Li N, Zhen X. Targeted to neuronal organelles for CNS drug development. Adv Drug Deliv Rev 2023; 200:115025. [PMID: 37516410 DOI: 10.1016/j.addr.2023.115025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 07/07/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
Significant evidences indicate that sub-cellular organelle dynamics is critical for both physiological and pathological events and therefore may be attractive drug targets displaying great therapeutic potential. Although the basic biological mechanism underlying the dynamics of intracellular organelles has been extensively studied, relative drug development is still limited. In the present review, we show that due to the development of technical advanced imaging tools, especially live cell imaging methods, intracellular organelle dynamics (including mitochondrial dynamics and membrane contact sites) can be dissected at the molecular level. Based on these identified molecular targets, we review and discuss the potential of drug development to target organelle dynamics, especially mitochondria dynamics and ER-organelle membrane contact dynamics, in the central nervous system for treating human diseases, including neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, Huntington's disease and amyotrophic lateral sclerosis.
Collapse
Affiliation(s)
- Zheng Ying
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China.
| | - Na Ye
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Qilian Ma
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Fan Chen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Ningning Li
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China
| | - Xuechu Zhen
- Jiangsu Key Laboratory of Neuropsychiatric Diseases and College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu 215123, China.
| |
Collapse
|
37
|
Moccia F, Fiorio Pla A, Lim D, Lodola F, Gerbino A. Intracellular Ca 2+ signalling: unexpected new roles for the usual suspect. Front Physiol 2023; 14:1210085. [PMID: 37576340 PMCID: PMC10413985 DOI: 10.3389/fphys.2023.1210085] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 07/18/2023] [Indexed: 08/15/2023] Open
Abstract
Cytosolic Ca2+ signals are organized in complex spatial and temporal patterns that underlie their unique ability to regulate multiple cellular functions. Changes in intracellular Ca2+ concentration ([Ca2+]i) are finely tuned by the concerted interaction of membrane receptors and ion channels that introduce Ca2+ into the cytosol, Ca2+-dependent sensors and effectors that translate the elevation in [Ca2+]i into a biological output, and Ca2+-clearing mechanisms that return the [Ca2+]i to pre-stimulation levels and prevent cytotoxic Ca2+ overload. The assortment of the Ca2+ handling machinery varies among different cell types to generate intracellular Ca2+ signals that are selectively tailored to subserve specific functions. The advent of novel high-speed, 2D and 3D time-lapse imaging techniques, single-wavelength and genetic Ca2+ indicators, as well as the development of novel genetic engineering tools to manipulate single cells and whole animals, has shed novel light on the regulation of cellular activity by the Ca2+ handling machinery. A symposium organized within the framework of the 72nd Annual Meeting of the Italian Society of Physiology, held in Bari on 14-16th September 2022, has recently addressed many of the unexpected mechanisms whereby intracellular Ca2+ signalling regulates cellular fate in healthy and disease states. Herein, we present a report of this symposium, in which the following emerging topics were discussed: 1) Regulation of water reabsorption in the kidney by lysosomal Ca2+ release through Transient Receptor Potential Mucolipin 1 (TRPML1); 2) Endoplasmic reticulum-to-mitochondria Ca2+ transfer in Alzheimer's disease-related astroglial dysfunction; 3) The non-canonical role of TRP Melastatin 8 (TRPM8) as a Rap1A inhibitor in the definition of some cancer hallmarks; and 4) Non-genetic optical stimulation of Ca2+ signals in the cardiovascular system.
Collapse
Affiliation(s)
- Francesco Moccia
- Laboratory of General Physiology, Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
| | | | - Dmitry Lim
- Department of Pharmaceutical Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Novara, Italy
| | - Francesco Lodola
- Department of Biotechnology and Biosciences, University of Milan-Bicocca, Milan, Italy
- Center for Nano Science and Technology @PoliMi, Istituto Italiano di Tecnologia, Milan, Italy
| | - Andrea Gerbino
- Department of Biosciences, Biotechnologies and Environment, University of Bari Aldo Moro, Bari, Italy
| |
Collapse
|
38
|
Yue P, Lv X, You J, Zou Y, Luo J, Lu Z, Cao H, Liu Z, Fan X, Ye Q. Hypothermic oxygenated perfusion attenuates DCD liver ischemia-reperfusion injury by activating the JAK2/STAT3/HAX1 pathway to regulate endoplasmic reticulum stress. Cell Mol Biol Lett 2023; 28:55. [PMID: 37438690 DOI: 10.1186/s11658-023-00466-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 06/14/2023] [Indexed: 07/14/2023] Open
Abstract
BACKGROUND Hepatic ischemia-reperfusion injury (IRI) in donation after cardiac death (DCD) donors is a major determinant of transplantation success. Endoplasmic reticulum (ER) stress plays a key role in hepatic IRI, with potential involvement of the Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3) pathway and the antiapoptotic protein hematopoietic-lineage substrate-1-associated protein X-1 (HAX1). In this study, we aimed to investigate the effects of hypothermic oxygenated perfusion (HOPE), an organ preservation modality, on ER stress and apoptosis during hepatic IRI in a DCD rat model. METHODS To investigate whether HOPE could improve IRI in DCD livers, levels of different related proteins were examined by western blotting and quantitative real-time polymerase chain reaction. Further expression analyses, immunohistochemical analyses, immunofluorescence staining, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining, and transmission electron microscopy were conducted to analyze the effects of HOPE on ER stress and apoptosis. To clarify the role of the JAK2/STAT3 pathway and HAX1 in this process, AG490 inhibitor, JAX1 plasmid transfection, co-immunoprecipitation (CO-IP), and flow cytometry analyses were conducted. RESULTS HOPE reduced liver injury and inflammation while alleviating ER stress and apoptosis in the DCD rat model. Mechanistically, HOPE inhibited unfolded protein responses by activating the JAK2/STAT3 pathway, thus reducing ER stress and apoptosis. Moreover, the activated JAK2/STAT3 pathway upregulated HAX1, promoting the interaction between HAX1 and SERCA2b to maintain ER calcium homeostasis. Upregulated HAX1 also modulated ER stress and apoptosis by inhibiting the inositol-requiring enzyme 1 (IRE1) pathway. CONCLUSIONS JAK2/STAT3-mediated upregulation of HAX1 during HOPE alleviates hepatic ER stress and apoptosis, indicating the JAK2/STAT3/HAX1 pathway as a potential target for IRI management during DCD liver transplantation.
Collapse
Affiliation(s)
- Pengpeng Yue
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Xiaoyan Lv
- Department of Hematology, Zhongnan Hospital of Wuhan University, Wuhan, 430071, China
| | - Jian You
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Yongkang Zou
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Jun Luo
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Zhongshan Lu
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Hankun Cao
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Zhongzhong Liu
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China
| | - Xiaoli Fan
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China.
| | - Qifa Ye
- Zhongnan Hospital of Wuhan University, Institute of Hepatobiliary Diseases of Wuhan University, Transplant Center of Wuhan University, National Quality Control Center for Donated Organ Procurement, Hubei Key Laboratory of Medical Technology on Transplantation, Hubei Clinical Research Center for Natural Polymer Biological Liver, Hubei Engineering Center of Natural Polymer-based Medical Materials, 430071, Wuhan, China.
- The Third Xiangya Hospital of Central South University, Research Center of National Health Ministry On Transplantation Medicine Engineering and Technology, Changsha, 410013, China.
| |
Collapse
|
39
|
Naón D, Hernández-Alvarez MI, Shinjo S, Wieczor M, Ivanova S, Martins de Brito O, Quintana A, Hidalgo J, Palacín M, Aparicio P, Castellanos J, Lores L, Sebastián D, Fernández-Veledo S, Vendrell J, Joven J, Orozco M, Zorzano A, Scorrano L. Splice variants of mitofusin 2 shape the endoplasmic reticulum and tether it to mitochondria. Science 2023; 380:eadh9351. [PMID: 37347868 DOI: 10.1126/science.adh9351] [Citation(s) in RCA: 21] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 05/12/2023] [Indexed: 06/24/2023]
Abstract
In eukaryotic cells, different organelles interact at membrane contact sites stabilized by tethers. Mitochondrial mitofusin 2 (MFN2) acts as a membrane tether that interacts with an unknown partner on the endoplasmic reticulum (ER). In this work, we identified the MFN2 splice variant ERMIT2 as the ER tethering partner of MFN2. Splicing of MFN2 produced ERMIT2 and ERMIN2, two ER-specific variants. ERMIN2 regulated ER morphology, whereas ERMIT2 localized at the ER-mitochondria interface and interacted with mitochondrial mitofusins to tether ER and mitochondria. This tethering allowed efficient mitochondrial calcium ion uptake and phospholipid transfer. Expression of ERMIT2 ameliorated the ER stress, inflammation, and fibrosis typical of liver-specific Mfn2 knockout mice. Thus, ER-specific MFN2 variants display entirely extramitochondrial MFN2 functions involved in interorganellar tethering and liver metabolic activities.
Collapse
Affiliation(s)
- Déborah Naón
- Department of Biology, University of Padua, 35121 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
| | - María Isabel Hernández-Alvarez
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- IBUB, Universitat de Barcelona, Barcelona, Spain
| | - Satoko Shinjo
- Department of Biology, University of Padua, 35121 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| | - Milosz Wieczor
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Department of Physical Chemistry, Gdansk University of Technology, 80-233 Gdańsk, Poland
| | - Saska Ivanova
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | | | - Albert Quintana
- Institute of Neurosciences, Universitat Autònoma de Barcelona, Bellaterra, Spain
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Juan Hidalgo
- Institute of Neurosciences, Universitat Autònoma de Barcelona, Bellaterra, Spain
- Department of Cellular Biology, Physiology and Immunology, Animal Physiology Unit, Faculty of Biosciences, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Manuel Palacín
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
- CIBER de Enfermedades Raras (CIBERER), Instituto de Salud Carlos III, Madrid, Spain
| | - Pilar Aparicio
- Department of Orthopaedics and Trauma Surgery, Parc Sanitari Sant Joan de Déu, Sant Boi de Llobregat, Barcelona, Spain
| | - Juan Castellanos
- Department of Orthopaedics and Trauma Surgery, Parc Sanitari Sant Joan de Déu, Sant Boi de Llobregat, Barcelona, Spain
| | - Luis Lores
- Pneumology Department, Hospital General Parc Sanitari Sant Joan de Déu, Sant Boi de Llobregat, Barcelona, Spain
| | - David Sebastián
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Sonia Fernández-Veledo
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- Department of Endocrinology and Nutrition, Hospital Universitari de Tarragona Joan XXIII, Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, Spain
- Medicine School, Universitat Rovira i Virgili, Tarragona and Reus, Spain
| | - Joan Vendrell
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
- Department of Endocrinology and Nutrition, Hospital Universitari de Tarragona Joan XXIII, Institut d'Investigació Sanitària Pere Virgili (IISPV), Tarragona, Spain
- Medicine School, Universitat Rovira i Virgili, Tarragona and Reus, Spain
| | - Jorge Joven
- Medicine School, Universitat Rovira i Virgili, Tarragona and Reus, Spain
- Unitat de Recerca Biomèdica, Institut d'Investigació Sanitària Pere Virgili, Hospital Universitari de Sant Joan, Reus, Spain
| | - Modesto Orozco
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
| | - Antonio Zorzano
- Institute for Research in Biomedicine (IRB Barcelona), Barcelona, Spain
- Departament de Bioquímica i Biomedicina Molecular, Universitat de Barcelona, Barcelona, Spain
- CIBER de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM), Madrid, Spain
| | - Luca Scorrano
- Department of Biology, University of Padua, 35121 Padova, Italy
- Veneto Institute of Molecular Medicine, 35129 Padova, Italy
| |
Collapse
|
40
|
Cho E, Woo Y, Suh Y, Suh BK, Kim SJ, Nhung TTM, Yoo JY, Nghi TD, Lee SB, Mun DJ, Park SK. Ratiometric measurement of MAM Ca 2+ dynamics using a modified CalfluxVTN. Nat Commun 2023; 14:3586. [PMID: 37328454 PMCID: PMC10276021 DOI: 10.1038/s41467-023-39343-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 06/06/2023] [Indexed: 06/18/2023] Open
Abstract
Mitochondria-associated ER membrane (MAM) is a structure where these calcium-regulating organelles form close physical contact sites for efficient Ca2+ crosstalk. Despite the central importance of MAM Ca2+ dynamics in diverse biological processes, directly and specifically measuring Ca2+ concentrations inside MAM is technically challenging. Here, we develop MAM-Calflux, a MAM-specific BRET-based Ca2+ indicator. The successful application of the bimolecular fluorescence complementation (BiFC) concept highlights Ca2+-responsive BRET signals in MAM. The BiFC strategy imparts dual functionality as a Ca2+ indicator and quantitative structural marker specific for MAM. As a ratiometric Ca2+ indicator, MAM-Calflux estimates steady-state MAM Ca2+ levels. Finally, it enables the visualization of uneven intracellular distribution of MAM Ca2+ and the elucidation of abnormally accumulated MAM Ca2+ from the neurons of Parkinson's disease mouse model in both steady-state and stimulated conditions. Therefore, we propose that MAM-Calflux can be a versatile tool for ratiometrically measuring dynamic inter-organellar Ca2+ communication.
Collapse
Affiliation(s)
- Eunbyul Cho
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Youngsik Woo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea.
| | - Yeongjun Suh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Bo Kyoung Suh
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Soo Jeong Kim
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Truong Thi My Nhung
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Jin Yeong Yoo
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Tran Diem Nghi
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Su Been Lee
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Dong Jin Mun
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea
| | - Sang Ki Park
- Department of Life Sciences, Pohang University of Science and Technology, Pohang, 37673, Republic of Korea.
| |
Collapse
|
41
|
He Q, Qu M, Shen T, Su J, Xu Y, Xu C, Barkat MQ, Cai J, Zhu H, Zeng LH, Wu X. Control of mitochondria-associated endoplasmic reticulum membranes by protein S-palmitoylation: Novel therapeutic targets for neurodegenerative diseases. Ageing Res Rev 2023; 87:101920. [PMID: 37004843 DOI: 10.1016/j.arr.2023.101920] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 03/30/2023] [Accepted: 03/30/2023] [Indexed: 04/03/2023]
Abstract
Mitochondria-associated endoplasmic reticulum membranes (MAMs) are dynamic coupling structures between mitochondria and the endoplasmic reticulum (ER). As a new subcellular structure, MAMs combine the two critical organelle functions. Mitochondria and the ER could regulate each other via MAMs. MAMs are involved in calcium (Ca2+) homeostasis, autophagy, ER stress, lipid metabolism, etc. Researchers have found that MAMs are closely related to metabolic syndrome and neurodegenerative diseases (NDs). The formation of MAMs and their functions depend on specific proteins. Numerous protein enrichments, such as the IP3R-Grp75-VDAC complex, constitute MAMs. The changes in these proteins govern the interaction between mitochondria and the ER; they also affect the biological functions of MAMs. S-palmitoylation is a reversible protein post-translational modification (PTM) that mainly occurs on protein cysteine residues. More and more studies have shown that the S-palmitoylation of proteins is closely related to their membrane localization. Here, we first briefly describe the composition and function of MAMs, reviewing the component and biological roles of MAMs mediated by S-palmitoylation, elaborating on S-palmitoylated proteins in Ca2+ flux, lipid rafts, and so on. We try to provide new insight into the molecular basis of MAMs-related diseases, mainly NDs. Finally, we propose potential drug compounds targeting S-palmitoylation.
Collapse
Affiliation(s)
- Qiangqiang He
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China; Department of Pharmacology, Hangzhou City University, Hangzhou 310015, China
| | - Meiyu Qu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Tingyu Shen
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jiakun Su
- Technology Center, China Tobacco Jiangxi Industrial Co. Ltd., Nanchang 330096, China
| | - Yana Xu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Chengyun Xu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Muhammad Qasim Barkat
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Jibao Cai
- Technology Center, China Tobacco Jiangxi Industrial Co. Ltd., Nanchang 330096, China
| | - Haibin Zhu
- Department of Gynecology, the First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China
| | - Ling-Hui Zeng
- Department of Pharmacology, Hangzhou City University, Hangzhou 310015, China.
| | - Ximei Wu
- Department of Pharmacology, Zhejiang University School of Medicine, Hangzhou 310058, China.
| |
Collapse
|
42
|
Nichtová Z, Fernandez-Sanz C, De La Fuente S, Yuan Y, Hurst S, Lanvermann S, Tsai HY, Weaver D, Baggett A, Thompson C, Bouchet-Marquis C, Várnai P, Seifert EL, Dorn GW, Sheu SS, Csordás G. Enhanced Mitochondria-SR Tethering Triggers Adaptive Cardiac Muscle Remodeling. Circ Res 2023; 132:e171-e187. [PMID: 37057625 PMCID: PMC10213149 DOI: 10.1161/circresaha.122.321833] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 03/29/2023] [Indexed: 04/15/2023]
Abstract
BACKGROUND Cardiac contractile function requires high energy from mitochondria, and Ca2+ from the sarcoplasmic reticulum (SR). Via local Ca2+ transfer at close mitochondria-SR contacts, cardiac excitation feedforward regulates mitochondrial ATP production to match surges in demand (excitation-bioenergetics coupling). However, pathological stresses may cause mitochondrial Ca2+ overload, excessive reactive oxygen species production and permeability transition, risking homeostatic collapse and myocyte loss. Excitation-bioenergetics coupling involves mitochondria-SR tethers but the role of tethering in cardiac physiology/pathology is debated. Endogenous tether proteins are multifunctional; therefore, nonselective targets to scrutinize interorganelle linkage. Here, we assessed the physiological/pathological relevance of selective chronic enhancement of cardiac mitochondria-SR tethering. METHODS We introduced to mice a cardiac muscle-specific engineered tether (linker) transgene with a fluorescent protein core and deployed 2D/3D electron microscopy, biochemical approaches, fluorescence imaging, in vivo and ex vivo cardiac performance monitoring and stress challenges to characterize the linker phenotype. RESULTS Expressed in the mature cardiomyocytes, the linker expanded and tightened individual mitochondria-junctional SR contacts; but also evoked a marked remodeling with large dense mitochondrial clusters that excluded dyads. Yet, excitation-bioenergetics coupling remained well-preserved, likely due to more longitudinal mitochondria-dyad contacts and nanotunnelling between mitochondria exposed to junctional SR and those sealed away from junctional SR. Remarkably, the linker decreased female vulnerability to acute massive β-adrenergic stress. It also reduced myocyte death and mitochondrial calcium-overload-associated myocardial impairment in ex vivo ischemia/reperfusion injury. CONCLUSIONS We propose that mitochondria-SR/endoplasmic reticulum contacts operate at a structural optimum. Although acute changes in tethering may cause dysfunction, upon chronic enhancement of contacts from early life, adaptive remodeling of the organelles shifts the system to a new, stable structural optimum. This remodeling balances the individually enhanced mitochondrion-junctional SR crosstalk and excitation-bioenergetics coupling, by increasing the connected mitochondrial pool and, presumably, Ca2+/reactive oxygen species capacity, which then improves the resilience to stresses associated with dysregulated hyperactive Ca2+ signaling.
Collapse
Affiliation(s)
- Zuzana Nichtová
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| | - Celia Fernandez-Sanz
- Center of Translational Medicine, TJUH, Philadelphia, PA, USA
- These authors contributed equally
| | - Sergio De La Fuente
- Center of Translational Medicine, TJUH, Philadelphia, PA, USA
- These authors contributed equally
| | - Yuexing Yuan
- Center of Translational Medicine, TJUH, Philadelphia, PA, USA
| | - Stephen Hurst
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| | | | - Hui-Ying Tsai
- Center of Translational Medicine, TJUH, Philadelphia, PA, USA
| | - David Weaver
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| | - Ariele Baggett
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| | | | | | - Péter Várnai
- Department of Physiology, Faculty of Medicine, Semmelweis Univ., Budapest, Hungary
| | - Erin L Seifert
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| | - Gerald W Dorn
- Center for Pharmacogenomics, John T. Milliken Dep. Med., WUSM, St Louis, MO, USA
| | - Shey-Shing Sheu
- Center of Translational Medicine, TJUH, Philadelphia, PA, USA
| | - György Csordás
- MitoCare, Pathology and Genomic Medicine, TJUH, Philadelphia, PA, USA
| |
Collapse
|
43
|
Kharechkina ES, Nikiforova AB, Kruglov AG. Regulation of Mitochondrial Permeability Transition Pore Opening by Monovalent Cations in Liver Mitochondria. Int J Mol Sci 2023; 24:ijms24119237. [PMID: 37298189 DOI: 10.3390/ijms24119237] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/16/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023] Open
Abstract
The opening of the permeability transition pore (PTP) in mitochondria is a key event in the initiation of cell death in various pathologic states, including ischemia/reperfusion. The activation of K+ transport into mitochondria protects cells from ischemia/reperfusion. However, the role of K+ transport in PTP regulation is unclear. Here, we studied the role of K+ and other monovalent cations in the regulation of the PTP opening in an in vitro model. The registration of the PTP opening, membrane potential, Ca2+-retention capacity, matrix pH, and K+ transport was performed using standard spectral and electrode techniques. We found that the presence of all cations tested in the medium (K+, Na+, choline+, and Li+) strongly stimulated the PTP opening compared with sucrose. Several possible reasons for this were examined: the effect of ionic strength, the influx of cations through selective and non-selective channels and exchangers, the suppression of Ca2+/H+ exchange, and the influx of anions. The data obtained indicate that the mechanism of PTP stimulation by cations includes the suppression of K+/H+ exchange and acidification of the matrix, which facilitates the influx of phosphate. Thus, the K+/H+ exchanger and the phosphate carrier together with selective K+ channels compose a PTP regulatory triad, which might operate in vivo.
Collapse
Affiliation(s)
- Ekaterina S Kharechkina
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, 142290 Moscow, Russia
| | - Anna B Nikiforova
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, 142290 Moscow, Russia
| | - Alexey G Kruglov
- Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Institutskaya 3, Pushchino, 142290 Moscow, Russia
| |
Collapse
|
44
|
Bian J, Su X, Yuan X, Zhang Y, Lin J, Li X. Endoplasmic reticulum membrane contact sites: cross-talk between membrane-bound organelles in plant cells. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:2956-2967. [PMID: 36847172 DOI: 10.1093/jxb/erad068] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Accepted: 02/20/2023] [Indexed: 05/21/2023]
Abstract
Eukaryotic cells contain organelles surrounded by monolayer or bilayer membranes. Organelles take part in highly dynamic and organized interactions at membrane contact sites, which play vital roles during development and response to stress. The endoplasmic reticulum extends throughout the cell and acts as an architectural scaffold to maintain the spatial distribution of other membrane-bound organelles. In this review, we highlight the structural organization, dynamics, and physiological functions of membrane contact sites between the endoplasmic reticulum and various membrane-bound organelles, especially recent advances in plants. We briefly introduce how the combined use of dynamic and static imaging techniques can enable monitoring of the cross-talk between organelles via membrane contact sites. Finally, we discuss future directions for research fields related to membrane contact.
Collapse
Affiliation(s)
- Jiahui Bian
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiao Su
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Xiaoyan Yuan
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Yuan Zhang
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| | - Jinxing Lin
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Botany, Chinese Academy of Sciences, Beijing 100083, China
| | - Xiaojuan Li
- Key Laboratory of Genetics and Breeding in Forest Trees and Ornamental Plants, Ministry of Education, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
- Institute of Tree Development and Genome Editing, College of Biological Sciences and Technology, Beijing Forestry University, Beijing 100083, China
| |
Collapse
|
45
|
Garcia-Casas P, Rossini M, Filadi R, Pizzo P. Mitochondrial Ca 2+ signaling and Alzheimer's disease: Too much or too little? Cell Calcium 2023; 113:102757. [PMID: 37192560 DOI: 10.1016/j.ceca.2023.102757] [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: 02/28/2023] [Revised: 05/08/2023] [Accepted: 05/09/2023] [Indexed: 05/18/2023]
Abstract
Alzheimer's disease (AD) is a neurodegenerative disease, caused by poorly known pathogenic mechanisms and aggravated by delayed therapeutic intervention, that still lacks an effective cure. However, it is clear that some important neurophysiological processes are altered years before the onset of clinical symptoms, offering the possibility of identifying biological targets useful for implementation of new therapies. Of note, evidence has been provided suggesting that mitochondria, pivotal organelles in sustaining neuronal energy demand and modulating synaptic activity, are dysfunctional in AD samples. In particular, alterations in mitochondrial Ca2+ signaling have been proposed as causal events for neurodegeneration, although the exact outcomes and molecular mechanisms of these defects, as well as their longitudinal progression, are not always clear. Here, we discuss the importance of a correct mitochondrial Ca2+ handling for neuronal physiology and summarize the latest findings on dysfunctional mitochondrial Ca2+ pathways in AD, analysing possible consequences contributing to the neurodegeneration that characterizes the disease.
Collapse
Affiliation(s)
- Paloma Garcia-Casas
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Department of Biochemistry and Molecular Biology and Physiology, School of Medicine, University of Valladolid, 47003 Valladolid, Spain
| | - Michela Rossini
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy
| | - Riccardo Filadi
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy.
| | - Paola Pizzo
- Department of Biomedical Sciences, University of Padova, 35131 Padua, Italy; Neuroscience Institute, National Research Council (CNR), 35131 Padua, Italy; Study Centre for Neurodegeneration (CESNE), University of Padova, 35131 Padua, Italy.
| |
Collapse
|
46
|
de Ridder I, Kerkhofs M, Lemos FO, Loncke J, Bultynck G, Parys JB. The ER-mitochondria interface, where Ca 2+ and cell death meet. Cell Calcium 2023; 112:102743. [PMID: 37126911 DOI: 10.1016/j.ceca.2023.102743] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2023] [Revised: 04/20/2023] [Accepted: 04/24/2023] [Indexed: 05/03/2023]
Abstract
Endoplasmic reticulum (ER)-mitochondria contact sites are crucial to allow Ca2+ flux between them and a plethora of proteins participate in tethering both organelles together. Inositol 1,4,5-trisphosphate receptors (IP3Rs) play a pivotal role at such contact sites, participating in both ER-mitochondria tethering and as Ca2+-transport system that delivers Ca2+ from the ER towards mitochondria. At the ER-mitochondria contact sites, the IP3Rs function as a multi-protein complex linked to the voltage-dependent anion channel 1 (VDAC1) in the outer mitochondrial membrane, via the chaperone glucose-regulated protein 75 (GRP75). This IP3R-GRP75-VDAC1 complex supports the efficient transfer of Ca2+ from the ER into the mitochondrial intermembrane space, from which the Ca2+ ions can reach the mitochondrial matrix through the mitochondrial calcium uniporter. Under physiological conditions, basal Ca2+ oscillations deliver Ca2+ to the mitochondrial matrix, thereby stimulating mitochondrial oxidative metabolism. However, when mitochondrial Ca2+ overload occurs, the increase in [Ca2+] will induce the opening of the mitochondrial permeability transition pore, thereby provoking cell death. The IP3R-GRP75-VDAC1 complex forms a hub for several other proteins that stabilize the complex and/or regulate the complex's ability to channel Ca2+ into the mitochondria. These proteins and their mechanisms of action are discussed in the present review with special attention for their role in pathological conditions and potential implication for therapeutic strategies.
Collapse
Affiliation(s)
- Ian de Ridder
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Martijn Kerkhofs
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Fernanda O Lemos
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Jens Loncke
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium
| | - Geert Bultynck
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
| | - Jan B Parys
- KU Leuven, Laboratory for Molecular and Cellular Signaling, Department of Cellular and Molecular Medicine & Leuven Kanker Instituut, Campus Gasthuisberg O/N-1 B-802, Herestraat 49, Leuven BE-3000, Belgium.
| |
Collapse
|
47
|
Tamada H. Three-dimensional ultrastructure analysis of organelles in injured motor neuron. Anat Sci Int 2023:10.1007/s12565-023-00720-y. [PMID: 37071350 DOI: 10.1007/s12565-023-00720-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Accepted: 03/23/2023] [Indexed: 04/19/2023]
Abstract
Morphological analysis of organelles is one of the important clues for understanding the cellular conditions and mechanisms occurring in cells. In particular, nanoscale information within crowded intracellular organelles of tissues provide more direct implications when compared to analyses of cells in culture or isolation. However, there are some difficulties in detecting individual shape using light microscopy, including super-resolution microscopy. Transmission electron microscopy (TEM), wherein the ultrastructure can be imaged at the membrane level, cannot determine the whole structure, and analyze it quantitatively. Volume EM, such as focused ion beam/scanning electron microscopy (FIB/SEM), can be a powerful tool to explore the details of three-dimensional ultrastructures even within a certain volume, and to measure several parameters from them. In this review, the advantages of FIB/SEM analysis in organelle studies are highlighted along with the introduction of mitochondrial analysis in injured motor neurons. This would aid in understanding the morphological details of mitochondria, especially those distributed in the cell bodies as well as in the axon initial segment (AIS) in mouse tissues. These regions have not been explored thus far due to the difficulties encountered in accessing their images by conditional microscopies. Some mechanisms of nerve regeneration have also been discussed with reference to the obtained findings. Finally, future perspectives on FIB/SEM are introduced. The combination of biochemical and genetic understanding of organelle structures and a nanoscale understanding of their three-dimensional distribution and morphology will help to match achievements in genomics and structural biology.
Collapse
Affiliation(s)
- Hiromi Tamada
- Functional Anatomy and Neuroscience, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-Ku, Nagoya, Aichi, 466-8550, Japan.
- Anatomy, Graduate School of Medicines, University of Fukui, Matsuokashimoaizuki, Eiheiji-Cho, Yoshida-Gun, Fukui, 910-1193, Japan.
| |
Collapse
|
48
|
Morris S, Molina-Riquelme I, Barrientos G, Bravo F, Aedo G, Gómez W, Lagos D, Verdejo H, Peischard S, Seebohm G, Psathaki OE, Eisner V, Busch KB. Inner mitochondrial membrane structure and fusion dynamics are altered in senescent human iPSC-derived and primary rat cardiomyocytes. BIOCHIMICA ET BIOPHYSICA ACTA. BIOENERGETICS 2023; 1864:148949. [PMID: 36493857 DOI: 10.1016/j.bbabio.2022.148949] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 11/17/2022] [Accepted: 11/30/2022] [Indexed: 12/12/2022]
Abstract
Dysfunction of the aging heart is a major cause of death in the human population. Amongst other tasks, mitochondria are pivotal to supply the working heart with ATP. The mitochondrial inner membrane (IMM) ultrastructure is tailored to meet these demands and to provide nano-compartments for specific tasks. Thus, function and morphology are closely coupled. Senescent cardiomyocytes from the mouse heart display alterations of the inner mitochondrial membrane. To study the relation between inner mitochondrial membrane architecture, dynamics and function is hardly possible in living organisms. Here, we present two cardiomyocyte senescence cell models that allow in cellular studies of mitochondrial performance. We show that doxorubicin treatment transforms human iPSC-derived cardiomyocytes and rat neonatal cardiomyocytes in an aged phenotype. The treated cardiomyocytes display double-strand breaks in the nDNA, have β-galactosidase activity, possess enlarged nuclei, and show p21 upregulation. Most importantly, they also display a compromised inner mitochondrial structure. This prompted us to test whether the dynamics of the inner membrane was also altered. We found that the exchange of IMM components after organelle fusion was faster in doxorubicin-treated cells than in control cells, with no change in mitochondrial fusion dynamics at the meso-scale. Such altered IMM morphology and dynamics may have important implications for local OXPHOS protein organization, exchange of damaged components, and eventually the mitochondrial bioenergetics function of the aged cardiomyocyte.
Collapse
Affiliation(s)
- Silke Morris
- Institute of Integrative Cell Biology and Physiology, Schlossplatz 5, Faculty of Biology, University of Muenster, 48149 Muenster, North-Rhine-Westphalia, Germany
| | - Isidora Molina-Riquelme
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Gonzalo Barrientos
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Francisco Bravo
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Geraldine Aedo
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Wileidy Gómez
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Daniel Lagos
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Hugo Verdejo
- Facultad de Medicina, División de Enfermedades Cardiovasculares, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile
| | - Stefan Peischard
- Institute for Genetics of Heart Diseases (IfGH), Department of Cardiovascular Medicine, University Hospital Münster, D-48149 Münster, North-Rhine-Westphalia, Germany
| | - Guiscard Seebohm
- Institute for Genetics of Heart Diseases (IfGH), Department of Cardiovascular Medicine, University Hospital Münster, D-48149 Münster, North-Rhine-Westphalia, Germany
| | - Olympia Ekaterini Psathaki
- Center of Cellular Nanoanalytics, Integrated Bioimaging Facility, University of Osnabrück, 49076 Osnabrück, Lower Saxony, Germany
| | - Verónica Eisner
- Departmento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Avda. Libertador Bernardo O´Higgins 340, Santiago de Chile, Chile.
| | - Karin B Busch
- Institute of Integrative Cell Biology and Physiology, Schlossplatz 5, Faculty of Biology, University of Muenster, 48149 Muenster, North-Rhine-Westphalia, Germany.
| |
Collapse
|
49
|
Nakatsu F, Tsukiji S. Chemo- and opto-genetic tools for dissecting the role of membrane contact sites in living cells: Recent advances and limitations. Curr Opin Chem Biol 2023; 73:102262. [PMID: 36731242 DOI: 10.1016/j.cbpa.2022.102262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/21/2022] [Accepted: 12/24/2022] [Indexed: 02/04/2023]
Abstract
Membrane contact sites (MCSs) are morphologically defined intracellular structures where cellular membranes are closely apposed. Recent progress has significantly advanced our understanding of MCSs with the use of new tools and techniques. Visualization of MCSs in living cells by split fluorescence proteins or FRET-based techniques tells us the dynamic property of MCSs. Manipulation of MCSs by chemically-induced dimerization (CID) or light-induced dimerization (LID) greatly contributes to our understanding of their functional aspects including inter-organelle lipid transport mediated by lipid transfer proteins (LTPs). Here we highlight recent advances in these tools and techniques as applied to MCSs, and we discuss their advantages and limitations.
Collapse
Affiliation(s)
- Fubito Nakatsu
- Department of Neurochemistry and Molecular Cell Biology, Niigata University School of Medicine and Graduate School of Medical/Dental Sciences, Niigata 951-8510, Japan.
| | - Shinya Tsukiji
- Department of Life Science and Applied Chemistry, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan; Department of Nanopharmaceutical Sciences, Graduate School of Engineering, Nagoya Institute of Technology, Nagoya 466-8555, Japan
| |
Collapse
|
50
|
Jeyarajan S, Zhang IX, Arvan P, Lentz SI, Satin LS. Simultaneous Measurement of Changes in Mitochondrial and Endoplasmic Reticulum Free Calcium in Pancreatic Beta Cells. BIOSENSORS 2023; 13:382. [PMID: 36979594 PMCID: PMC10046164 DOI: 10.3390/bios13030382] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 02/28/2023] [Accepted: 03/08/2023] [Indexed: 05/28/2023]
Abstract
The free calcium (Ca2+) levels in pancreatic beta cell organelles have been the subject of many recent investigations. Under pathophysiological conditions, disturbances in these pools have been linked to altered intracellular communication and cellular dysfunction. To facilitate studies of subcellular Ca2+ signaling in beta cells and, particularly, signaling between the endoplasmic reticulum (ER) and mitochondria, we designed a novel dual Ca2+ sensor which we termed DS-1. DS-1 encodes two stoichiometrically fluorescent proteins within a single plasmid, G-CEPIA-er, targeted to the ER and R-CEPIA3-mt, targeted to mitochondria. Our goal was to simultaneously measure the ER and mitochondrial Ca2+ in cells in real time. The Kds of G-CEPIA-er and R-CEPIA3-mt for Ca2+ are 672 and 3.7 μM, respectively. Confocal imaging of insulin-secreting INS-1 832/13 expressing DS-1 confirmed that the green and red fluorophores correctly colocalized with organelle-specific fluorescent markers as predicted. Further, we tested whether DS-1 exhibited the functional properties expected by challenging an INS-1 cell to glucose concentrations or drugs having well-documented effects on the ER and mitochondrial Ca2+ handling. The data obtained were consistent with those seen using other single organelle targeted probes. These results taken together suggest that DS-1 is a promising new approach for investigating Ca2+ signaling within multiple organelles of the cell.
Collapse
Affiliation(s)
- Sivakumar Jeyarajan
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48105, USA; (S.J.)
| | - Irina X Zhang
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48105, USA; (S.J.)
| | - Peter Arvan
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, MI 48105, USA
- Department of Molecular & Integrative Physiology, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Stephen I. Lentz
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Leslie S. Satin
- Department of Pharmacology, University of Michigan Medical School, Ann Arbor, MI 48105, USA; (S.J.)
- Department of Internal Medicine, Division of Metabolism, Endocrinology & Diabetes, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| |
Collapse
|