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Li Y, Zhang Z, Zhang Z, Zheng N, Ding X. Empagliflozin, a sodium-glucose cotransporter inhibitor enhancing mitochondrial action and cardioprotection in metabolic syndrome. J Cell Physiol 2024. [PMID: 38764242 DOI: 10.1002/jcp.31264] [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: 09/05/2023] [Revised: 03/13/2024] [Accepted: 03/18/2024] [Indexed: 05/21/2024]
Abstract
Metabolic syndrome (MetS) has a large clinical population nowadays, usually due to excessive energy intake and lack of exercise. During MetS, excess nutrients stress the mitochondria, resulting in relative hypoxia in tissues and organs, even when blood supply is not interrupted or reduced, making mitochondrial dysfunction a central pathogenesis of cardiovascular disease in the MetS. Sodium-glucose cotransporter 2 inhibitors were designed as a hyperglycemic drug that acts on the renal tubules to block sugar reabsorption in primary urine. Recently they have been shown to have anti-inflammatory and other protective effects on cardiomyocytes in MetS, and have also been recommended in the latest heart failure guidelines as a routine therapy. Among these inhibitors, empagliflozin shows better clinical promise due to less influence from glomerular filtration rate. This review focuses on the mitochondrial mechanisms of empagliflozin, which underlie the anti-inflammatory and recover cellular functions in MetS cardiomyocytes, including stabilizing calcium concentration, mediating metabolic reprogramming, maintaining homeostasis of mitochondrial quantity and quality, stable mitochondrial DNA copy number, and repairing damaged mitochondrial DNA.
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Affiliation(s)
- Yunhao Li
- Graduate School, China Medical University, Shenyang, China
- Department of Cardiology, General Hospital of Northern Theater Command, Shenyang, China
| | - Zhanming Zhang
- Faculty of Science, The University of Hong Kong, Hong Kong, China
| | - Zheming Zhang
- Graduate School, China Medical University, Shenyang, China
- Department of Thoracic Surgery, The First Hospital of China Medical University, Shenyang, China
| | - Ningning Zheng
- Department of Pathophysiology, College of Basic Medical Science, China Medical University, Shenyang, China
| | - Xudong Ding
- Department of Anesthesiology, Shengjing Hospital of China Medical University, Shenyang, China
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2
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Mattedi F, Lloyd-Morris E, Hirth F, Vagnoni A. Optogenetic cleavage of the Miro GTPase reveals the direct consequences of real-time loss of function in Drosophila. PLoS Biol 2023; 21:e3002273. [PMID: 37590319 PMCID: PMC10465005 DOI: 10.1371/journal.pbio.3002273] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 08/29/2023] [Accepted: 07/22/2023] [Indexed: 08/19/2023] Open
Abstract
Miro GTPases control mitochondrial morphology, calcium homeostasis, and regulate mitochondrial distribution by mediating their attachment to the kinesin and dynein motor complex. It is not clear, however, how Miro proteins spatially and temporally integrate their function as acute disruption of protein function has not been performed. To address this issue, we have developed an optogenetic loss of function "Split-Miro" allele for precise control of Miro-dependent mitochondrial functions in Drosophila. Rapid optogenetic cleavage of Split-Miro leads to a striking rearrangement of the mitochondrial network, which is mediated by mitochondrial interaction with the microtubules. Unexpectedly, this treatment did not impact the ability of mitochondria to buffer calcium or their association with the endoplasmic reticulum. While Split-Miro overexpression is sufficient to augment mitochondrial motility, sustained photocleavage shows that Split-Miro is surprisingly dispensable to maintain elevated mitochondrial processivity. In adult fly neurons in vivo, Split-Miro photocleavage affects both mitochondrial trafficking and neuronal activity. Furthermore, functional replacement of endogenous Miro with Split-Miro identifies its essential role in the regulation of locomotor activity in adult flies, demonstrating the feasibility of tuning animal behaviour by real-time loss of protein function.
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Affiliation(s)
- Francesca Mattedi
- Department of Basic and Clinical Neurosciences, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Ethlyn Lloyd-Morris
- Department of Basic and Clinical Neurosciences, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Frank Hirth
- Department of Basic and Clinical Neurosciences, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
| | - Alessio Vagnoni
- Department of Basic and Clinical Neurosciences, Maurice Wohl Clinical Neuroscience Institute, Institute of Psychiatry, Psychology and Neuroscience, King’s College London, London, United Kingdom
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3
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Chang YW, Tony Yang T, Chen MC, Liaw YG, Yin CF, Lin-Yan XQ, Huang TY, Hou JT, Hung YH, Hsu CL, Huang HC, Juan HF. Spatial and temporal dynamics of ATP synthase from mitochondria toward the cell surface. Commun Biol 2023; 6:427. [PMID: 37072500 PMCID: PMC10113393 DOI: 10.1038/s42003-023-04785-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Accepted: 03/30/2023] [Indexed: 04/20/2023] Open
Abstract
Ectopic ATP synthase complex (eATP synthase), located on cancer cell surface, has been reported to possess catalytic activity that facilitates the generation of ATP in the extracellular environment to establish a suitable microenvironment and to be a potential target for cancer therapy. However, the mechanism of intracellular ATP synthase complex transport remains unclear. Using a combination of spatial proteomics, interaction proteomics, and transcriptomics analyses, we find ATP synthase complex is first assembled in the mitochondria and subsequently delivered to the cell surface along the microtubule via the interplay of dynamin-related protein 1 (DRP1) and kinesin family member 5B (KIF5B). We further demonstrate that the mitochondrial membrane fuses to the plasma membrane in turn to anchor ATP syntheses on the cell surface using super-resolution imaging and real-time fusion assay in live cells. Our results provide a blueprint of eATP synthase trafficking and contribute to the understanding of the dynamics of tumor progression.
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Grants
- 109-2221-E-010-012-MY3 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MOST 109-2221-E-010-011-MY3 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MOST 109-2327-B-006-004 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MOST 109-2320-B-002-017-MY3 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- MOST 109-2221-E-002-161-MY3 Ministry of Science and Technology, Taiwan (Ministry of Science and Technology of Taiwan)
- NTU-110L8808 Ministry of Education (Ministry of Education, Republic of China (Taiwan))
- NTU-CC-109L104702-2 Ministry of Education (Ministry of Education, Republic of China (Taiwan))
- NTU-110L7103 Ministry of Education (Ministry of Education, Republic of China (Taiwan))
- NTU-111L7107 Ministry of Education (Ministry of Education, Republic of China (Taiwan))
- NTU-CC-112L892102 Ministry of Education (Ministry of Education, Republic of China (Taiwan))
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Affiliation(s)
- Yi-Wen Chang
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - T Tony Yang
- Department of Electrical Engineering, National Taiwan University, Taipei, 106, Taiwan
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, 106, Taiwan
| | - Min-Chun Chen
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Y-Geh Liaw
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Chieh-Fan Yin
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Xiu-Qi Lin-Yan
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Ting-Yu Huang
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Jen-Tzu Hou
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Yi-Hsuan Hung
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
| | - Chia-Lang Hsu
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan
- Department of Medical Research, National Taiwan University Hospital, Taipei, 100, Taiwan
| | - Hsuan-Cheng Huang
- Institute of Biomedical Informatics, National Yang Ming Chiao Tung University, Taipei, 112, Taiwan.
| | - Hsueh-Fen Juan
- Department of Life Science, Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, 106, Taiwan.
- Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, 106, Taiwan.
- Center for Computational and Systems Biology, National Taiwan University, Taipei, 106, Taiwan.
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4
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Sabui A, Biswas M, Somvanshi PR, Kandagiri P, Gorla M, Mohammed F, Tammineni P. Decreased anterograde transport coupled with sustained retrograde transport contributes to reduced axonal mitochondrial density in tauopathy neurons. Front Mol Neurosci 2022; 15:927195. [PMID: 36245925 PMCID: PMC9561864 DOI: 10.3389/fnmol.2022.927195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Accepted: 08/22/2022] [Indexed: 11/13/2022] Open
Abstract
Mitochondria are essential organelle required for neuronal homeostasis. Mitochondria supply ATP and buffer calcium at synaptic terminals. However, the complex structural geometry of neurons poses a unique challenge in transporting mitochondria to synaptic terminals. Kinesin motors supply mitochondria to the axonal compartments, while cytoplasmic dynein is required for retrograde transport. Despite the importance of presynaptic mitochondria, how and whether axonal mitochondrial transport and distribution are altered in tauopathy neurons remain poorly studied. In the current study, we have shown that anterograde transport of mitochondria is reduced in P301L neurons, while there is no change in the retrograde transport. Consistently, axonal mitochondrial abundance is reduced in P301L neurons. We further studied the possible role of two opposing motor proteins on mitochondrial transport and found that mitochondrial association of kinesin is decreased significantly in P301L cells. Interestingly, fitting our experimental data into mathematical equations suggested a possible rise in dynein activity to maintain retrograde flux in P301L cells. Our data indicate that decreased kinesin-mediated transport coupled with sustained retrograde transport might reduce axonal mitochondria in tauopathy neurons, thus contributing to the synaptic deficits in Alzheimer’s disease (AD) and other tauopathies.
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Affiliation(s)
- Anusruti Sabui
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Mitali Biswas
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | | | - Preethi Kandagiri
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Madhavi Gorla
- Centre for Biotechnology, Institute of Science and Technology (IST), Jawaharlal Nehru Technological University Hyderabad, Hyderabad, India
| | - Fareed Mohammed
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Prasad Tammineni
- Department of Animal Biology, School of Life Sciences, University of Hyderabad, Hyderabad, India
- *Correspondence: Prasad Tammineni,
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5
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Nahacka Z, Novak J, Zobalova R, Neuzil J. Miro proteins and their role in mitochondrial transfer in cancer and beyond. Front Cell Dev Biol 2022; 10:937753. [PMID: 35959487 PMCID: PMC9358137 DOI: 10.3389/fcell.2022.937753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/04/2022] [Indexed: 11/24/2022] Open
Abstract
Mitochondria are organelles essential for tumor cell proliferation and metastasis. Although their main cellular function, generation of energy in the form of ATP is dispensable for cancer cells, their capability to drive their adaptation to stress originating from tumor microenvironment makes them a plausible therapeutic target. Recent research has revealed that cancer cells with damaged oxidative phosphorylation import healthy (functional) mitochondria from surrounding stromal cells to drive pyrimidine synthesis and cell proliferation. Furthermore, it has been shown that energetically competent mitochondria are fundamental for tumor cell migration, invasion and metastasis. The spatial positioning and transport of mitochondria involves Miro proteins from a subfamily of small GTPases, localized in outer mitochondrial membrane. Miro proteins are involved in the structure of the MICOS complex, connecting outer and inner-mitochondrial membrane; in mitochondria-ER communication; Ca2+ metabolism; and in the recycling of damaged organelles via mitophagy. The most important role of Miro is regulation of mitochondrial movement and distribution within (and between) cells, acting as an adaptor linking organelles to cytoskeleton-associated motor proteins. In this review, we discuss the function of Miro proteins in various modes of intercellular mitochondrial transfer, emphasizing the structure and dynamics of tunneling nanotubes, the most common transfer modality. We summarize the evidence for and propose possible roles of Miro proteins in nanotube-mediated transfer as well as in cancer cell migration and metastasis, both processes being tightly connected to cytoskeleton-driven mitochondrial movement and positioning.
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Affiliation(s)
- Zuzana Nahacka
- Laboratory of Molecular Therapy, Institute of Biotechnology, Czech Academy of Sciences, Prague, Czechia
- *Correspondence: Zuzana Nahacka, ; Jiri Neuzil,
| | - Jaromir Novak
- Laboratory of Molecular Therapy, Institute of Biotechnology, Czech Academy of Sciences, Prague, Czechia
- Faculty of Science, Charles University, Prague, Czechia
| | - Renata Zobalova
- Laboratory of Molecular Therapy, Institute of Biotechnology, Czech Academy of Sciences, Prague, Czechia
| | - Jiri Neuzil
- Laboratory of Molecular Therapy, Institute of Biotechnology, Czech Academy of Sciences, Prague, Czechia
- School of Pharmacy and Medical Science, Griffith University, Southport, QLD, Australia
- *Correspondence: Zuzana Nahacka, ; Jiri Neuzil,
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6
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Fagbadebo FO, Kaiser PD, Zittlau K, Bartlick N, Wagner TR, Froehlich T, Jarjour G, Nueske S, Scholz A, Traenkle B, Macek B, Rothbauer U. A Nanobody-Based Toolset to Monitor and Modify the Mitochondrial GTPase Miro1. Front Mol Biosci 2022; 9:835302. [PMID: 35359597 PMCID: PMC8960383 DOI: 10.3389/fmolb.2022.835302] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 02/08/2022] [Indexed: 12/24/2022] Open
Abstract
The mitochondrial outer membrane (MOM)-anchored GTPase Miro1, is a central player in mitochondrial transport and homeostasis. The dysregulation of Miro1 in amyotrophic lateral sclerosis (ALS) and Parkinson’s disease (PD) suggests that Miro1 may be a potential biomarker or drug target in neuronal disorders. However, the molecular functionality of Miro1 under (patho-) physiological conditions is poorly known. For a more comprehensive understanding of the molecular functions of Miro1, we have developed Miro1-specific nanobodies (Nbs) as novel research tools. We identified seven Nbs that bind either the N- or C-terminal GTPase domain of Miro1 and demonstrate their application as research tools for proteomic and imaging approaches. To visualize the dynamics of Miro1 in real time, we selected intracellularly functional Nbs, which we reformatted into chromobodies (Cbs) for time-lapse imaging of Miro1. By genetic fusion to an Fbox domain, these Nbs were further converted into Miro1-specific degrons and applied for targeted degradation of Miro1 in live cells. In summary, this study presents a collection of novel Nbs that serve as a toolkit for advanced biochemical and intracellular studies and modulations of Miro1, thereby contributing to the understanding of the functional role of Miro1 in disease-derived model systems.
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Affiliation(s)
| | - Philipp D. Kaiser
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Katharina Zittlau
- Quantitative Proteomics, Department of Biology, Interfaculty Institute of Cell Biology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Natascha Bartlick
- Interfaculty Institute of Biochemistry, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Teresa R. Wagner
- Pharmaceutical Biotechnology, Eberhard Karls University Tübingen, Tübingen, Germany
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Theresa Froehlich
- Pharmaceutical Biotechnology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Grace Jarjour
- Pharmaceutical Biotechnology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Stefan Nueske
- Livestock Center of the Faculty of Veterinary Medicine, Ludwig Maximilians University Munich, Oberschleissheim, Germany
| | - Armin Scholz
- Livestock Center of the Faculty of Veterinary Medicine, Ludwig Maximilians University Munich, Oberschleissheim, Germany
| | - Bjoern Traenkle
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
| | - Boris Macek
- Quantitative Proteomics, Department of Biology, Interfaculty Institute of Cell Biology, Eberhard Karls University Tübingen, Tübingen, Germany
| | - Ulrich Rothbauer
- Pharmaceutical Biotechnology, Eberhard Karls University Tübingen, Tübingen, Germany
- NMI Natural and Medical Sciences Institute at the University of Tübingen, Reutlingen, Germany
- *Correspondence: Ulrich Rothbauer,
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7
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Trigo D, Avelar C, Fernandes M, Sá J, da Cruz E Silva O. Mitochondria, energy, and metabolism in neuronal health and disease. FEBS Lett 2022; 596:1095-1110. [PMID: 35088449 DOI: 10.1002/1873-3468.14298] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2021] [Revised: 01/10/2022] [Accepted: 01/17/2022] [Indexed: 11/09/2022]
Abstract
Mitochondria are associated with various cellular activities critical to homeostasis, particularly in the nervous system. The plastic architecture of the mitochondrial network and its dynamic structure play crucial roles in ensuring that varying energetic demands are rapidly met to maintain neuronal and axonal energy homeostasis. Recent evidence associates ageing and neurodegeneration with anomalous neuronal metabolism, as age-dependent alterations of neuronal metabolism are now believed to occur prior to neurodegeneration. The brain has a high energy demand, which makes it particularly sensitive to mitochondrial dysfunction. Distinct cellular events causing oxidative stress or disruption of metabolism and mitochondrial homeostasis can trigger a neuropathology. This review explores the bioenergetic hypothesis for the neurodegenerative pathomechanisms, discussing factors leading to age-related brain hypometabolism and its contribution to cognitive decline. Recent research on the mitochondrial network in healthy nervous system cells, its response to stress and how it is affected by pathology, as well as current contributions to novel therapeutic approaches will be highlighted.
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Affiliation(s)
- Diogo Trigo
- Neuroscience and Signalling Laboratory, Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, 3810-193, Aveiro, Portugal.,Medical Sciences Department, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Catarina Avelar
- Medical Sciences Department, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Miguel Fernandes
- Medical Sciences Department, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Juliana Sá
- Medical Sciences Department, University of Aveiro, 3810-193, Aveiro, Portugal
| | - Odete da Cruz E Silva
- Neuroscience and Signalling Laboratory, Institute of Biomedicine (iBiMED), Department of Medical Sciences, University of Aveiro, 3810-193, Aveiro, Portugal.,Medical Sciences Department, University of Aveiro, 3810-193, Aveiro, Portugal
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8
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Zinsmaier KE. Mitochondrial Miro GTPases coordinate mitochondrial and peroxisomal dynamics. Small GTPases 2021; 12:372-398. [PMID: 33183150 PMCID: PMC8583064 DOI: 10.1080/21541248.2020.1843957] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 10/22/2020] [Accepted: 10/26/2020] [Indexed: 12/18/2022] Open
Abstract
Mitochondria and peroxisomes are highly dynamic, multifunctional organelles. Both perform key roles for cellular physiology and homoeostasis by mediating bioenergetics, biosynthesis, and/or signalling. To support cellular function, they must be properly distributed, of proper size, and be able to interact with other organelles. Accumulating evidence suggests that the small atypical GTPase Miro provides a central signalling node to coordinate mitochondrial as well as peroxisomal dynamics. In this review, I summarize our current understanding of Miro-dependent functions and molecular mechanisms underlying the proper distribution, size and function of mitochondria and peroxisomes.
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Affiliation(s)
- Konrad E. Zinsmaier
- Departments of Neuroscience and Molecular and Cellular Biology, University of Arizona, Tucson, AZ, USA
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Nahacka Z, Zobalova R, Dubisova M, Rohlena J, Neuzil J. Miro proteins connect mitochondrial function and intercellular transport. Crit Rev Biochem Mol Biol 2021; 56:401-425. [PMID: 34139898 DOI: 10.1080/10409238.2021.1925216] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Mitochondria are organelles present in most eukaryotic cells, where they play major and multifaceted roles. The classical notion of the main mitochondrial function as the powerhouse of the cell per se has been complemented by recent discoveries pointing to mitochondria as organelles affecting a number of other auxiliary processes. They go beyond the classical energy provision via acting as a relay point of many catabolic and anabolic processes, to signaling pathways critically affecting cell growth by their implication in de novo pyrimidine synthesis. These additional roles further underscore the importance of mitochondrial homeostasis in various tissues, where its deregulation promotes a number of pathologies. While it has long been known that mitochondria can move within a cell to sites where they are needed, recent research has uncovered that mitochondria can also move between cells. While this intriguing field of research is only emerging, it is clear that mobilization of mitochondria requires a complex apparatus that critically involves mitochondrial proteins of the Miro family, whose role goes beyond the mitochondrial transfer, as will be covered in this review.
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Affiliation(s)
- Zuzana Nahacka
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czech Republic
| | - Renata Zobalova
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czech Republic
| | - Maria Dubisova
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czech Republic.,Faculty of Science, Charles University, Prague, Czech Republic
| | - Jakub Rohlena
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czech Republic
| | - Jiri Neuzil
- Institute of Biotechnology, Czech Academy of Sciences, Prague-West, Czech Republic.,School of Medical Science, Griffith University, Southport, Australia
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10
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Ihenacho UK, Meacham KA, Harwig MC, Widlansky ME, Hill RB. Mitochondrial Fission Protein 1: Emerging Roles in Organellar Form and Function in Health and Disease. Front Endocrinol (Lausanne) 2021; 12:660095. [PMID: 33841340 PMCID: PMC8027123 DOI: 10.3389/fendo.2021.660095] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 03/05/2021] [Indexed: 12/13/2022] Open
Abstract
Mitochondrial fission protein 1 (Fis1) was identified in yeast as being essential for mitochondrial division or fission and subsequently determined to mediate human mitochondrial and peroxisomal fission. Yet, its exact functions in humans, especially in regard to mitochondrial fission, remains an enigma as genetic deletion of Fis1 elongates mitochondria in some cell types, but not others. Fis1 has also been identified as an important component of apoptotic and mitophagic pathways suggesting the protein may have multiple, essential roles. This review presents current perspectives on the emerging functions of Fis1 and their implications in human health and diseases, with an emphasis on Fis1's role in both endocrine and neurological disorders.
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Affiliation(s)
| | - Kelsey A. Meacham
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Megan Cleland Harwig
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
| | - Michael E. Widlansky
- Department of Medicine, Division of Cardiovascular Medicine, Medical College of Wisconsin, Milwaukee, WI, United States
| | - R. Blake Hill
- Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI, United States
- *Correspondence: R. Blake Hill,
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11
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Panchal K, Tiwari AK. Miro (Mitochondrial Rho GTPase), a key player of mitochondrial axonal transport and mitochondrial dynamics in neurodegenerative diseases. Mitochondrion 2020; 56:118-135. [PMID: 33127590 DOI: 10.1016/j.mito.2020.10.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/14/2020] [Accepted: 10/19/2020] [Indexed: 02/07/2023]
Abstract
Miro (mitochondrial Rho GTPases) a mitochondrial outer membrane protein, plays a vital role in the microtubule-based mitochondrial axonal transport, mitochondrial dynamics (fusion and fission) and Mito-Ca2+ homeostasis. It forms a major protein complex with Milton (an adaptor protein), kinesin and dynein (motor proteins), and facilitates bidirectional mitochondrial axonal transport such as anterograde and retrograde transport. By forming this protein complex, Miro facilitates the mitochondrial axonal transport and fulfills the neuronal energy demand, maintain the mitochondrial homeostasis and neuronal survival. It has been demonstrated that altered mitochondrial biogenesis, improper mitochondrial axonal transport, and mitochondrial dynamics are the early pathologies associated with most of the neurodegenerative diseases (NDs). Being the sole mitochondrial outer membrane protein associated with mitochondrial axonal transport-related processes, Miro proteins can be one of the key players in various NDs such as Alzheimer's disease (AD), Parkinson's disease (PD), Amyotrophic lateral sclerosis (ALS) and Huntington's disease (HD). Thus, in the current review, we have discussed the evolutionarily conserved Miro proteins and its role in the pathogenesis of the various NDs. From this, we indicated that Miro proteins may act as a potential target for a novel therapeutic intervention for the treatment of various NDs.
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Affiliation(s)
- Komal Panchal
- Genetics & Developmental Biology Laboratory, Department of Biological Sciences & Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India
| | - Anand Krishna Tiwari
- Genetics & Developmental Biology Laboratory, Department of Biological Sciences & Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India.
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12
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Panchal K, Tiwari AK. Miro, a Rho GTPase genetically interacts with Alzheimer's disease-associated genes ( Tau, Aβ42 and Appl) in Drosophila melanogaster. Biol Open 2020; 9:bio049569. [PMID: 32747449 PMCID: PMC7489762 DOI: 10.1242/bio.049569] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 07/24/2020] [Indexed: 12/13/2022] Open
Abstract
Miro (mitochondrial Rho GTPases), a mitochondrial outer membrane protein, facilitates mitochondrial axonal transport along the microtubules to facilitate neuronal function. It plays an important role in regulating mitochondrial dynamics (fusion and fission) and cellular energy generation. Thus, Miro might be associated with the key pathologies of several neurodegenerative diseases (NDs) including Alzheimer's disease (AD). In the present manuscript, we have demonstrated the possible genetic interaction between Miro and AD-related genes such as Tau, Aβ42 and Appl in Drosophila melanogaster Ectopic expression of Tau, Aβ42 and Appl induced a rough eye phenotype, defects in phototaxis and climbing activity, and shortened lifespan in the flies. In our study, we have observed that overexpression of Miro improves the rough eye phenotype, behavioral activities (climbing and phototaxis) and ATP level in AD model flies. Further, the improvement examined in AD-related phenotypes was correlated with decreased oxidative stress, cell death and neurodegeneration in Miro overexpressing AD model flies. Thus, the obtained results suggested that Miro genetically interacts with AD-related genes in Drosophila and has the potential to be used as a therapeutic target for the design of therapeutic strategies for NDs.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Komal Panchal
- Genetics and Developmental Biology Laboratory, Department of Biological Sciences and Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India
| | - Anand Krishna Tiwari
- Genetics and Developmental Biology Laboratory, Department of Biological Sciences and Biotechnology, Institute of Advanced Research (IAR), Koba, Gandhinagar, Gujarat 382426, India
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Bocanegra JL, Adikes R, Quintero OA. Myosin XIX. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1239:439-451. [PMID: 32451871 DOI: 10.1007/978-3-030-38062-5_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The birth of widely available genomic databases at the turn of the millennium led to the identification of many previously unknown myosin genes and identification of novel classes of myosin, including MYO19. Further sequence analysis has revealed the unique evolutionary history of class XIX myosins. MYO19 is found in species ranging from vertebrates to some unicellular organisms, while it has been lost from some lineages containing traditional experimental model organisms. Unique sequences in the motor domain suggest class-specific mechanochemistry that may relate to its cellular function as a mitochondria-associated motor. Work over the past 10 years has demonstrated that MYO19 is an actin-activated ATPase capable of actin-based transport, and investigation of some of the conserved differences within the motor domain indicate their importance in MYO19 motor activity. The cargo-binding MyMOMA tail domain contains two distinct mechanisms of interaction with mitochondrial outer membrane components, and perturbation of MYO19 expression leads to alterations in mitochondrial movement and dynamics that impact cell function. This chapter summarizes the current state of the field and highlights potential new directions of inquiry.
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Affiliation(s)
| | - Rebecca Adikes
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA
| | - Omar A Quintero
- Department of Biology, University of Richmond, Richmond, VA, USA.
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14
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Peng X, Li L, Zhang M, Zhao Q, Wu K, Bai R, Ruan Y, Liu N. Sodium-Glucose Cotransporter 2 Inhibitors Potentially Prevent Atrial Fibrillation by Ameliorating Ion Handling and Mitochondrial Dysfunction. Front Physiol 2020; 11:912. [PMID: 32848857 PMCID: PMC7417344 DOI: 10.3389/fphys.2020.00912] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Accepted: 07/08/2020] [Indexed: 12/14/2022] Open
Abstract
Sodium-glucose cotransporter 2 inhibitors (SGLT2i) are a novel class of glucose-lowering agents that significantly improve the prognosis of patients with type 2 diabetes (T2D) and heart failure. SGLT2i has recently been implicated in the treatment of atrial fibrillation (AF) with clinical data demonstrating that these agents decrease the incidence of AF events in patients with T2D. Fundamental findings have suggested that SGLT2i may alleviate atrial electrical and structural remodeling. The underlying mechanisms of SGLT2i are likely associated with balancing the sodium and calcium handling disorders and mitigating the mitochondrial dysfunction in atrial myocytes. This review illustrates the advances in understanding the underlying mechanisms of SGLT2i as an evolving treatment modality for AF.
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Affiliation(s)
| | | | | | | | | | | | | | - Nian Liu
- Department of Cardiology, Beijing Anzhen Hospital, Capital Medical University, Beijing, China
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15
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Quintanilla RA, Tapia-Monsalves C, Vergara EH, Pérez MJ, Aranguiz A. Truncated Tau Induces Mitochondrial Transport Failure Through the Impairment of TRAK2 Protein and Bioenergetics Decline in Neuronal Cells. Front Cell Neurosci 2020; 14:175. [PMID: 32848607 PMCID: PMC7406829 DOI: 10.3389/fncel.2020.00175] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2020] [Accepted: 05/22/2020] [Indexed: 12/22/2022] Open
Abstract
Mitochondria are highly specialized organelles essential for the synapse, and their impairment contributes to the neurodegeneration in Alzheimer's disease (AD). Previously, we studied the role of caspase-3-cleaved tau in mitochondrial dysfunction in AD. In neurons, the presence of this AD-relevant tau form induced mitochondrial fragmentation with a concomitant reduction in the expression of Opa1, a mitochondrial fission regulator. More importantly, we showed that caspase-cleaved tau affects mitochondrial transport, decreasing the number of moving mitochondria in the neuronal processes without affecting their velocity rate. However, the molecular mechanisms involved in these events are unknown. We studied the possible role of motor proteins (kinesin 1 and dynein) and mitochondrial protein adaptors (RhoT1/T2, syntaphilin, and TRAK2) in the mitochondrial transport failure induced by caspase-cleaved tau. We expressed green fluorescent protein (GFP), GFP-full-length, and GPF-caspase-3-cleaved tau proteins in rat hippocampal neurons and immortalized cortical neurons (CN 1.4) and analyzed the expression and localization of these proteins involved in mitochondrial transport regulation. We observed that hippocampal neurons expressing caspase-cleaved tau showed a significant accumulation of a mitochondrial population in the soma. These changes were accompanied by evident mitochondrial bioenergetic deficits, including depolarization, oxidative stress, and a significant reduction in ATP production. More critically, caspase-cleaved tau significantly decreased the expression of TRAK2 in immortalized and primary hippocampal neurons without affecting RhoT1/T2 and syntaphilin levels. Also, when we analyzed the expression of motor proteins-Kinesin 1 (KIF5) and Dynein-we did not detect changes in their expression, localization, and binding to the mitochondria. Interestingly, the expression of truncated tau significantly increases the association of TRAK2 with mitochondria compared with neuronal cells expressing full-length tau. Altogether these results indicate that caspase-cleaved tau may affect mitochondrial transport through the increase of TRAK2-mitochondria binding and reduction of ATP production available for the process of movement of these organelles. These observations are novel and represent a set of exciting findings whereby tau pathology could affect mitochondrial distribution in neurons, an event that may contribute to synaptic failure observed in AD.
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Affiliation(s)
- Rodrigo A. Quintanilla
- Laboratory of Neurodegenerative Diseases, Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Santiago, Chile
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16
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Azevedo RDS, Falcão KVG, Amaral IPG, Leite ACR, Bezerra RS. Mitochondria as targets for toxicity and metabolism research using zebrafish. Biochim Biophys Acta Gen Subj 2020; 1864:129634. [PMID: 32417171 DOI: 10.1016/j.bbagen.2020.129634] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2020] [Revised: 05/09/2020] [Accepted: 05/11/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND The study of mitochondrial functions in zebrafish was initiated before the 1990s and has effectively supported many of the recent scientific advances in the functional studies of mitochondria. SCOPE OF REVIEW This work elaborates various peculiarities and general advances in the study of mitochondria using this animal model. MAJOR CONCLUSIONS The inclusion of zebrafish models in scientific research was initiated with structural studies of mitochondria. Then, toxicological studies involving chemical compounds were undertaken. Currently, there is a decisive tendency to use zebrafish to understand how chemicals impair mitochondrial bioenergetics. Zebrafish modeling has been fruitful for the analysis of ion homeostasis, especially for Ca2+ transport, since zebrafish and mammals have the same set of Ca2+ transporters and mitochondrial membrane microdomains. Based on zebrafish embryo studies, our understanding of ROS generation has also led to new insights. GENERAL SIGNIFICANCE For the study of mitochondria, a new era was begun with the inclusion of zebrafish in bioenergetics research.
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Affiliation(s)
- Rafael D S Azevedo
- Biochemistry Department, Federal University of Pernambuco - UFPE, Recife, PE, Brazil.
| | - Kivia V G Falcão
- Biochemistry Department, Federal University of Pernambuco - UFPE, Recife, PE, Brazil
| | - Ian P G Amaral
- Biotechnology Center, Federal University of Paraiba - UFPB, João Pessoa, PB, Brazil
| | - Ana C R Leite
- Institute of Chemistry and Biotecnhology, Federal University of Alagoas - UFAL, Maceió, AL, Brazil
| | - Ranilson S Bezerra
- Biochemistry Department, Federal University of Pernambuco - UFPE, Recife, PE, Brazil
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17
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Fu H, Zhou H, Yu X, Xu J, Zhou J, Meng X, Zhao J, Zhou Y, Chisholm AD, Xu S. Wounding triggers MIRO-1 dependent mitochondrial fragmentation that accelerates epidermal wound closure through oxidative signaling. Nat Commun 2020; 11:1050. [PMID: 32103012 PMCID: PMC7044169 DOI: 10.1038/s41467-020-14885-x] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/10/2020] [Indexed: 12/19/2022] Open
Abstract
Organisms respond to tissue damage through the upregulation of protective responses which restore tissue structure and metabolic function. Mitochondria are key sources of intracellular oxidative metabolic signals that maintain cellular homeostasis. Here we report that tissue and cellular wounding triggers rapid and reversible mitochondrial fragmentation. Elevated mitochondrial fragmentation either in fzo-1 fusion-defective mutants or after acute drug treatment accelerates actin-based wound closure. Wounding triggered mitochondrial fragmentation is independent of the GTPase DRP-1 but acts via the mitochondrial Rho GTPase MIRO-1 and cytosolic Ca2+. The fragmented mitochondria and accelerated wound closure of fzo-1 mutants are dependent on MIRO-1 function. Genetic and transcriptomic analyzes show that enhanced mitochondrial fragmentation accelerates wound closure via the upregulation of mtROS and Cytochrome P450. Our results reveal how mitochondrial dynamics respond to cellular and tissue injury and promote tissue repair. Mitochondria are important organelles that generate and respond to signals to maintain cellular homeostasis. Here the authors show that wounding triggers GTPase MIRO-1- and calcium-dependent mitochondrial fragmentation, which aids tissue wound repair through cytochrome P450 and mitochondrial reactive oxygen species.
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Affiliation(s)
- Hongying Fu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Hengda Zhou
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China.,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China
| | - Xinghai Yu
- Department of System Biology, School of Life Science, Wuhan University, 430072, Wuhan, China
| | - Jingxiu Xu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China.,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China
| | - Jinghua Zhou
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Xinan Meng
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Jianzhi Zhao
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China
| | - Yu Zhou
- Department of System Biology, School of Life Science, Wuhan University, 430072, Wuhan, China
| | - Andrew D Chisholm
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA, 92093, USA
| | - Suhong Xu
- Center for Stem Cell and Regenerative Medicine and Department of Cardiology of The Second Affiliated Hospital, Zhejiang University School of Medicine, 310058, Hangzhou, China. .,The Zhejiang University-University of Edinburgh Institute, 718 East Haizhou Rd., Haining, 314400, Zhejiang, China. .,Women's Hospital of Zhejiang University, School of Medicine Hangzhou, 310058, Hangzhou, China.
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18
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Eberhardt EL, Ludlam AV, Tan Z, Cianfrocco MA. Miro: A molecular switch at the center of mitochondrial regulation. Protein Sci 2020; 29:1269-1284. [PMID: 32056317 DOI: 10.1002/pro.3839] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Revised: 02/03/2020] [Accepted: 02/06/2020] [Indexed: 12/24/2022]
Abstract
The orchestration of mitochondria within the cell represents a critical aspect of cell biology. At the center of this process is the outer mitochondrial membrane protein, Miro. Miro coordinates diverse cellular processes by regulating connections between organelles and the cytoskeleton that range from mediating contacts between the endoplasmic reticulum and mitochondria to the regulation of both actin and microtubule motor proteins. Recently, a number of cell biological, biochemical, and protein structure studies have helped to characterize the myriad roles played by Miro. In addition to answering questions regarding Miro's function, these studies have opened the door to new avenues in the study of Miro in the cell. This review will focus on summarizing recent findings for Miro's structure, function, and activity while highlighting key questions that remain unanswered.
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Affiliation(s)
- Emily L Eberhardt
- Life Sciences Institute, Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
- Cellular and Molecular Biology Program, University of Michigan, Ann Arbor, Michigan
| | - Anthony V Ludlam
- Life Sciences Institute, Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
| | - Zhenyu Tan
- Life Sciences Institute, Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
- Biophysics Program, University of Michigan, Ann Arbor, Michigan
| | - Michael A Cianfrocco
- Life Sciences Institute, Department of Biological Chemistry, University of Michigan, Ann Arbor, Michigan
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19
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Olmedo I, Pino G, Riquelme JA, Aranguiz P, Díaz MC, López-Crisosto C, Lavandero S, Donoso P, Pedrozo Z, Sánchez G. Inhibition of the proteasome preserves Mitofusin-2 and mitochondrial integrity, protecting cardiomyocytes during ischemia-reperfusion injury. Biochim Biophys Acta Mol Basis Dis 2019; 1866:165659. [PMID: 31891806 DOI: 10.1016/j.bbadis.2019.165659] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 12/13/2019] [Accepted: 12/24/2019] [Indexed: 12/18/2022]
Abstract
Cardiomyocyte loss is the main cause of myocardial dysfunction following an ischemia-reperfusion (IR) injury. Mitochondrial dysfunction and altered mitochondrial network dynamics play central roles in cardiomyocyte death. Proteasome inhibition is cardioprotective in the setting of IR; however, the mechanisms underlying this protection are not well-understood. Several proteins that regulate mitochondrial dynamics and energy metabolism, including Mitofusin-2 (Mfn2), are degraded by the proteasome. The aim of this study was to evaluate whether proteasome inhibition can protect cardiomyocytes from IR damage by maintaining Mfn2 levels and preserving mitochondrial network integrity. Using ex vivo Langendorff-perfused rat hearts and in vitro neonatal rat ventricular myocytes, we showed that the proteasome inhibitor MG132 reduced IR-induced cardiomyocyte death. Moreover, MG132 preserved mitochondrial mass, prevented mitochondrial network fragmentation, and abolished IR-induced reductions in Mfn2 levels in heart tissue and cultured cardiomyocytes. Interestingly, Mfn2 overexpression also prevented cardiomyocyte death. This effect was apparently specific to Mfn2, as overexpression of Miro1, another protein implicated in mitochondrial dynamics, did not confer the same protection. Our results suggest that proteasome inhibition protects cardiomyocytes from IR damage. This effect could be partly mediated by preservation of Mfn2 and therefore mitochondrial integrity.
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Affiliation(s)
- Ivonne Olmedo
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile
| | - Gonzalo Pino
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile
| | - Jaime A Riquelme
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380492, Chile; Departamento de Química Farmacológica y Toxicológica, Facultad de Ciencias Químicas y Farmacéuticas, Universidad de Chile, Santiago de Chile 8380492, Chile
| | - Pablo Aranguiz
- Escuela de Química y Farmacia, Facultad de Medicina, Universidad Andrés Bello, Viña del Mar 2520000, Chile
| | - Magda C Díaz
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile; Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380492, Chile; Grupo de Investigación en Ciencias Básicas y Clínicas de la Salud, Pontificia Universidad Javeriana de Cali, Colombia
| | - Camila López-Crisosto
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380492, Chile
| | - Sergio Lavandero
- Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380492, Chile; Corporación Centro de Estudios Científicos de las Enfermedades Crónicas (CECEC), Santiago de Chile 7680201, Chile; Department of Internal Medicine (Cardiology Division), University of Texas Southwestern Medical Center, Dallas, TX 75390-8573, USA
| | - Paulina Donoso
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile
| | - Zully Pedrozo
- Programa de Fisiología y Biofísica, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile; Advanced Center for Chronic Diseases (ACCDiS), Facultad de Ciencias Químicas y Farmacéuticas & Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380492, Chile.
| | - Gina Sánchez
- Programa de Fisiopatología, Instituto de Ciencias Biomédicas (ICBM), Facultad de Medicina, Universidad de Chile, Santiago de Chile 8380453, Chile.
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20
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Dautt-Castro M, Estrada-Rivera M, Olguin-Martínez I, Rocha-Medina MDC, Islas-Osuna MA, Casas-Flores S. TBRG-1 a Ras-like protein in Trichoderma virens involved in conidiation, development, secondary metabolism, mycoparasitism, and biocontrol unveils a new family of Ras-GTPases. Fungal Genet Biol 2019; 136:103292. [PMID: 31730908 DOI: 10.1016/j.fgb.2019.103292] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2019] [Revised: 10/07/2019] [Accepted: 10/31/2019] [Indexed: 01/02/2023]
Abstract
Ras-GTPases are nucleotide hydrolases involved in key cellular processes. In fungi, Ras-GTPases regulate conidiation, development, virulence, and interactions with other fungi or plants. Trichoderma spp. are filamentous saprophytic fungi, widely distributed along all latitudes, characterized by their rapid growth and metabolic diversity. Many species of this genus interact with other fungi, animals or plants. Furthermore, these fungi are used as biocontrol agents due to their ability to antagonize phytopathogenic fungi and oomycetes, through competence, antibiosis, and parasitism. However, the genetic and molecular regulation of these processes is scarcely described in these fungi. In this work, we investigated the role of the gene tbrg-1 product (GenBank accession number XP_013956100; JGI ID: Tv_70852) of T. virens during its interaction with other fungi and plants. Sequence analyses predicted that TBRG-1 bears the characteristic domains of Ras-GTPases; however, its size (1011 aa) is 3- to 4-times bigger compared with classical GTPases. Interestingly, phylogenetic analyses grouped the TBRG-1 protein with hypothetical proteins of similar sizes, sharing conserved regions; whereas other known Ras-GTPases were perfectly grouped with their respective families. These facts led us to classify TBRG-1 into a new family of Ras-GTPases, the Big Ras-GTPases (BRG). Therefore, the gene was named tbrg-1 (TrichodermaBigRas-GTPase-1). Quantification of conidia and scanning electron microscopy showed that the mutants-lacking tbrg-1 produced less conidia, as well as a delayed conidiophore development compared to the wild-type (wt). Moreover, a deregulation of conidiation-related genes (con-10, con-13, and stuA) was observed in tbrg-1-lacking strains, which indicates that TBRG-1 is necessary for proper conidiophore and conidia development. Furthermore, the lack of tbrg-1 affected positively the antagonistic capability of T. virens against the phytopathogens Rhizoctonia solani, Sclerotium rolfsii, and Fusarium oxysporum, which was consistent with the expression patterns of mycoparasitism-related genes, sp1 and cht1, that code for a protease and for a chitinase, respectively. Furthermore, the antibiosis effect of mycelium-free culture filtrates of Δtbrg-1 against R. solani was considerably enhanced. The expression of secondary metabolism-related genes, particularly gliP, showed an upregulation in Δtbrg-1, which paralleled an increase in gliotoxin production as compared to the wt. These results indicate that TBRG-1 plays a negative role in secondary metabolism and antagonism. Unexpectedly, the biocontrol activity of Δtbrg-1 was ineffective to protect the tomato seeds and seedlings against R. solani. On the contrary, Δtbrg-1 behaved like a plant pathogen, indicating that TBRG-1 is probably implicated in the recognition process for establishing a beneficial relationship with plants.
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Affiliation(s)
- Mitzuko Dautt-Castro
- IPICYT, División de Biología Molecular, Laboratorio de Genómica Funcional y Comparativa, San Luis Potosí, S.L.P., Mexico
| | - Magnolia Estrada-Rivera
- IPICYT, División de Biología Molecular, Laboratorio de Genómica Funcional y Comparativa, San Luis Potosí, S.L.P., Mexico
| | - Ignacio Olguin-Martínez
- IPICYT, División de Biología Molecular, Laboratorio de Genómica Funcional y Comparativa, San Luis Potosí, S.L.P., Mexico
| | - Ma Del Carmen Rocha-Medina
- IPICYT, Laboratorio Nacional de Biotecnología Agrícola, Médica y Ambiental, San Luis Potosí, S.L.P., Mexico
| | - María A Islas-Osuna
- Laboratorio de Genética y Biología Molecular de Plantas. Centro de Investigación en Alimentación y Desarrollo, A.C. Hermosillo, Sonora, Mexico
| | - Sergio Casas-Flores
- IPICYT, División de Biología Molecular, Laboratorio de Genómica Funcional y Comparativa, San Luis Potosí, S.L.P., Mexico.
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21
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Nemani N, Carvalho E, Tomar D, Dong Z, Ketschek A, Breves SL, Jaña F, Worth AM, Heffler J, Palaniappan P, Tripathi A, Subbiah R, Riitano MF, Seelam A, Manfred T, Itoh K, Meng S, Sesaki H, Craigen WJ, Rajan S, Shanmughapriya S, Caplan J, Prosser BL, Gill DL, Stathopulos PB, Gallo G, Chan DC, Mishra P, Madesh M. MIRO-1 Determines Mitochondrial Shape Transition upon GPCR Activation and Ca 2+ Stress. Cell Rep 2019; 23:1005-1019. [PMID: 29694881 DOI: 10.1016/j.celrep.2018.03.098] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 02/22/2018] [Accepted: 03/21/2018] [Indexed: 01/08/2023] Open
Abstract
Mitochondria shape cytosolic calcium ([Ca2+]c) transients and utilize the mitochondrial Ca2+ ([Ca2+]m) in exchange for bioenergetics output. Conversely, dysregulated [Ca2+]c causes [Ca2+]m overload and induces permeability transition pore and cell death. Ablation of MCU-mediated Ca2+ uptake exhibited elevated [Ca2+]c and failed to prevent stress-induced cell death. The mechanisms for these effects remain elusive. Here, we report that mitochondria undergo a cytosolic Ca2+-induced shape change that is distinct from mitochondrial fission and swelling. [Ca2+]c elevation, but not MCU-mediated Ca2+ uptake, appears to be essential for the process we term mitochondrial shape transition (MiST). MiST is mediated by the mitochondrial protein Miro1 through its EF-hand domain 1 in multiple cell types. Moreover, Ca2+-dependent disruption of Miro1/KIF5B/tubulin complex is determined by Miro1 EF1 domain. Functionally, Miro1-dependent MiST is essential for autophagy/mitophagy that is attenuated in Miro1 EF1 mutants. Thus, Miro1 is a cytosolic Ca2+ sensor that decodes metazoan Ca2+ signals as MiST.
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Affiliation(s)
- Neeharika Nemani
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Edmund Carvalho
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Dhanendra Tomar
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Zhiwei Dong
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Andrea Ketschek
- Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Sarah L Breves
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Fabián Jaña
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Alison M Worth
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Julie Heffler
- Department of Physiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Palaniappan Palaniappan
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Aparna Tripathi
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Ramasamy Subbiah
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Massimo F Riitano
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Ajay Seelam
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Thomas Manfred
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Kie Itoh
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Shuxia Meng
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Hiromi Sesaki
- Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - William J Craigen
- Department of Molecular and Human Genetics, The Mitochondrial Diagnostic Laboratory, Baylor College of Medicine, Houston, TX 77030, USA
| | - Sudarsan Rajan
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Santhanam Shanmughapriya
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - Jeffrey Caplan
- Department of Biological Sciences, Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA
| | - Benjamin L Prosser
- Department of Physiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Donald L Gill
- Department of Cellular and Molecular Physiology, Penn State Hershey College of Medicine, Hershey, PA 17033, USA
| | - Peter B Stathopulos
- Department of Physiology and Pharmacology, Western University, London, ON N6A 5C1, Canada
| | - Gianluca Gallo
- Department of Anatomy and Cell Biology, Shriners Hospitals Pediatric Research Center, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA
| | - David C Chan
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125, USA
| | - Prashant Mishra
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Muniswamy Madesh
- Department of Medical Genetics and Molecular Biochemistry, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA; Center for Translational Medicine, Lewis Katz School of Medicine at Temple University, Philadelphia, PA 19140, USA.
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22
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Gómez-Mendoza DP, Marques FD, Melo-Braga MN, Sprenger RR, Sinisterra RD, Kjeldsen F, Santos RA, Verano-Braga T. Angiotensin-(1-7) oral treatment after experimental myocardial infarction leads to downregulation of CXCR4. J Proteomics 2019; 208:103486. [DOI: 10.1016/j.jprot.2019.103486] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2019] [Revised: 08/05/2019] [Accepted: 08/10/2019] [Indexed: 11/27/2022]
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23
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Dietz JV, Bohovych I, Viana MP, Khalimonchuk O. Proteolytic regulation of mitochondrial dynamics. Mitochondrion 2019; 49:289-304. [PMID: 31029640 DOI: 10.1016/j.mito.2019.04.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2019] [Accepted: 04/19/2019] [Indexed: 12/23/2022]
Abstract
Spatiotemporal changes in the abundance, shape, and cellular localization of the mitochondrial network, also known as mitochondrial dynamics, are now widely recognized to play a key role in mitochondrial and cellular physiology as well as disease states. This process involves coordinated remodeling of the outer and inner mitochondrial membranes by conserved dynamin-like guanosine triphosphatases and their partner molecules in response to various physiological and stress stimuli. Although the core machineries that mediate fusion and partitioning of the mitochondrial network have been extensively characterized, many aspects of their function and regulation are incompletely understood and only beginning to emerge. In the present review we briefly summarize current knowledge about how the key mitochondrial dynamics-mediating factors are regulated via selective proteolysis by mitochondrial and cellular proteolytic machineries.
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Affiliation(s)
- Jonathan V Dietz
- Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, United States of America
| | - Iryna Bohovych
- Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, United States of America
| | - Martonio Ponte Viana
- Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, United States of America
| | - Oleh Khalimonchuk
- Department of Biochemistry, University of Nebraska, Lincoln, NE 68588, United States of America; Nebraska Redox Biology Center, University of Nebraska, Lincoln, NE 68588, United States of America; Fred & Pamela Buffett Cancer Center, University of Nebraska Medical Center, Omaha, NE 68198, United States of America.
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24
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Cao JL, Adaniya SM, Cypress MW, Suzuki Y, Kusakari Y, Jhun BS, O-Uchi J. Role of mitochondrial Ca 2+ homeostasis in cardiac muscles. Arch Biochem Biophys 2019; 663:276-287. [PMID: 30684463 PMCID: PMC6469710 DOI: 10.1016/j.abb.2019.01.027] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Revised: 01/10/2019] [Accepted: 01/22/2019] [Indexed: 12/22/2022]
Abstract
Recent discoveries of the molecular identity of mitochondrial Ca2+ influx/efflux mechanisms have placed mitochondrial Ca2+ transport at center stage in views of cellular regulation in various cell-types/tissues. Indeed, mitochondria in cardiac muscles also possess the molecular components for efficient uptake and extraction of Ca2+. Over the last several years, multiple groups have taken advantage of newly available molecular information about these proteins and applied genetic tools to delineate the precise mechanisms for mitochondrial Ca2+ handling in cardiomyocytes and its contribution to excitation-contraction/metabolism coupling in the heart. Though mitochondrial Ca2+ has been proposed as one of the most crucial secondary messengers in controlling a cardiomyocyte's life and death, the detailed mechanisms of how mitochondrial Ca2+ regulates physiological mitochondrial and cellular functions in cardiac muscles, and how disorders of this mechanism lead to cardiac diseases remain unclear. In this review, we summarize the current controversies and discrepancies regarding cardiac mitochondrial Ca2+ signaling that remain in the field to provide a platform for future discussions and experiments to help close this gap.
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Affiliation(s)
- Jessica L Cao
- Cardiovascular Research Center, Rhode Island Hospital, Providence, RI, USA; Department of Medicine, Division of Cardiology, The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Stephanie M Adaniya
- Cardiovascular Research Center, Rhode Island Hospital, Providence, RI, USA; Department of Medicine, Division of Cardiology, The Warren Alpert Medical School of Brown University, Providence, RI, USA; Lillehei Heart Institute, Department of Medicine, Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA
| | - Michael W Cypress
- Lillehei Heart Institute, Department of Medicine, Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA
| | - Yuta Suzuki
- Lillehei Heart Institute, Department of Medicine, Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA
| | - Yoichiro Kusakari
- Department of Cell Physiology, The Jikei University School of Medicine, Minato-ku, Tokyo, Japan
| | - Bong Sook Jhun
- Lillehei Heart Institute, Department of Medicine, Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA
| | - Jin O-Uchi
- Lillehei Heart Institute, Department of Medicine, Cardiovascular Division, University of Minnesota, Minneapolis, MN, USA.
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25
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Trigo D, Goncalves MB, Corcoran JPT. The regulation of mitochondrial dynamics in neurite outgrowth by retinoic acid receptor β signaling. FASEB J 2019; 33:7225-7235. [PMID: 30857414 PMCID: PMC6529336 DOI: 10.1096/fj.201802097r] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Neuronal regeneration is a highly energy-demanding process that greatly relies on axonal mitochondrial transport to meet the enhanced metabolic requirements. Mature neurons typically fail to regenerate after injury, partly because of mitochondrial motility and energy deficits in injured axons. Retinoic acid receptor (RAR)-β signaling is involved in axonal and neurite regeneration. Here we investigate the effect of RAR-β signaling on mitochondrial trafficking during neurite outgrowth and find that it enhances their proliferation, speed, and movement toward the growing end of the neuron via hypoxia-inducible factor 1α signaling. We also show that RAR-β signaling promotes the binding of the mitochondria to the anchoring protein, glucose-related protein 75, at the growing tip of neurite, thus allowing them to provide energy and metabolic roles required for neurite outgrowth.—Trigo, D., Goncalves, M. B., Corcoran, J. P. T. The regulation of mitochondrial dynamics in neurite outgrowth by retinoic acid receptor β signaling.
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Affiliation(s)
- Diogo Trigo
- The Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Maria B Goncalves
- The Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Jonathan P T Corcoran
- The Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
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26
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Peters DT, Kay L, Eswaran J, Lakey JH, Soundararajan M. Human Miro Proteins Act as NTP Hydrolases through a Novel, Non-Canonical Catalytic Mechanism. Int J Mol Sci 2018; 19:ijms19123839. [PMID: 30513825 PMCID: PMC6321465 DOI: 10.3390/ijms19123839] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 01/13/2023] Open
Abstract
Mitochondria are highly dynamic organelles that play a central role in multiple cellular processes, including energy metabolism, calcium homeostasis and apoptosis. Miro proteins (Miros) are “atypical” Ras superfamily GTPases that display unique domain architecture and subcellular localisation regulating mitochondrial transport, autophagy and calcium sensing. Here, we present systematic catalytic domain characterisation and structural analyses of human Miros. Despite lacking key conserved catalytic residues (equivalent to Ras Y32, T35, G60 and Q61), the Miro N-terminal GTPase domains display GTPase activity. Surprisingly, the C-terminal GTPase domains previously assumed to be “relic” domains were also active. Moreover, Miros show substrate promiscuity and function as NTPases. Molecular docking and structural analyses of Miros revealed unusual features in the Switch I and II regions, facilitating promiscuous substrate binding and suggesting the usage of a novel hydrolytic mechanism. The key substitution in position 13 in the Miros leads us to suggest the existence of an “internal arginine finger”, allowing an unusual catalytic mechanism that does not require GAP protein. Together, the data presented here indicate novel catalytic functions of human Miro atypical GTPases through altered catalytic mechanisms.
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Affiliation(s)
- Daniel T Peters
- Institute for Cell and Molecular Biosciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
| | - Laura Kay
- Department of Applied Sciences Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
| | - Jeyanthy Eswaran
- Northern Institute for Cancer Research, Newcastle University, Herschel Building, Newcastle upon Tyne, NE1 7RU, UK.
| | - Jeremy H Lakey
- Institute for Cell and Molecular Biosciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
| | - Meera Soundararajan
- Department of Applied Sciences Faculty of Health and Life Sciences, Northumbria University, Newcastle upon Tyne NE1 8ST, UK.
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27
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Walch L, Pellier E, Leng W, Lakisic G, Gautreau A, Contremoulins V, Verbavatz JM, Jackson CL. GBF1 and Arf1 interact with Miro and regulate mitochondrial positioning within cells. Sci Rep 2018; 8:17121. [PMID: 30459446 PMCID: PMC6244289 DOI: 10.1038/s41598-018-35190-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 10/28/2018] [Indexed: 02/08/2023] Open
Abstract
The spatial organization of cells depends on coordination between cytoskeletal systems and intracellular organelles. The Arf1 small G protein and its activator GBF1 are important regulators of Golgi organization, maintaining its morphology and function. Here we show that GBF1 and its substrate Arf1 regulate the spatial organization of mitochondria in a microtubule-dependent manner. Miro is a mitochondrial membrane protein that interacts through adaptors with microtubule motor proteins such as cytoplasmic dynein, the major microtubule minus end directed motor. We demonstrate a physical interaction between GBF1 and Miro, and also between the active GTP-bound form of Arf1 and Miro. Inhibition of GBF1, inhibition of Arf1 activation, or overexpression of Miro, caused a collapse of the mitochondrial network towards the centrosome. The change in mitochondrial morphology upon GBF1 inhibition was due to a two-fold increase in the time engaged in retrograde movement compared to control conditions. Electron tomography revealed that GBF1 inhibition also resulted in larger mitochondria with more complex morphology. Miro silencing or drug inhibition of cytoplasmic dynein activity blocked the GBF1-dependent repositioning of mitochondria. Our results show that blocking GBF1 function promotes dynein- and Miro-dependent retrograde mitochondrial transport along microtubules towards the microtubule-organizing center, where they form an interconnected network.
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Affiliation(s)
- Laurence Walch
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Emilie Pellier
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany
| | - Goran Lakisic
- CNRS UMR7654, Ecole Polytechnique, Palaiseau, France
| | | | - Vincent Contremoulins
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France
| | - Jean-Marc Verbavatz
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France.
| | - Catherine L Jackson
- Institut Jacques Monod, UMR7592 CNRS Université Paris-Diderot, Sorbonne Paris Cité, Paris, France.
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28
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Castro IG, Schrader M. Miro1 - the missing link to peroxisome motility. Commun Integr Biol 2018; 11:e1526573. [PMID: 30534345 PMCID: PMC6284566 DOI: 10.1080/19420889.2018.1526573] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 09/06/2018] [Indexed: 11/16/2022] Open
Abstract
Peroxisomes are ubiquitous, highly dynamic, multifunctional compartments in eukaryotic cells, which perform key roles in cellular lipid metabolism and redox balance. Like other membrane-bound organelles, peroxisomes must move in the cellular landscape to perform localized functions, interact with other organelles and to properly distribute during cell division. However, our current knowledge of peroxisome motility in mammalian cells is still very limited. Recently, three independent studies have identified Miro1 as a regulator of peroxisome motility in mammalian cells. In these studies, the authors show that Miro1 is targeted to peroxisomes in several cell lines, in a process that relies on its interaction with the peroxisomal chaperone Pex19. Interestingly, however, different conclusions are drawn about which Miro1 isoforms are targeted to peroxisomes, how it interacts with Pex19 and most importantly, the type of motility Miro1 is regulating.
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Affiliation(s)
- Inês G. Castro
- Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel
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29
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Sun X, St John JC. Modulation of mitochondrial DNA copy number in a model of glioblastoma induces changes to DNA methylation and gene expression of the nuclear genome in tumours. Epigenetics Chromatin 2018; 11:53. [PMID: 30208958 PMCID: PMC6136172 DOI: 10.1186/s13072-018-0223-z] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 09/06/2018] [Indexed: 01/23/2023] Open
Abstract
Background There are multiple copies of mitochondrial DNA (mtDNA) present in each cell type, and they are strictly regulated in a cell-specific manner by a group of nuclear-encoded mtDNA-specific replication factors. This strict regulation of mtDNA copy number is mediated by cell-specific DNA methylation of these replication factors. Glioblastoma multiforme, HSR-GBM1, cells are hyper-methylated and maintain low mtDNA copy number to support their tumorigenic status. We have previously shown that when HSR-GBM1 cells with 50% of their original mtDNA content were inoculated into mice, tumours grew more aggressively than non-depleted cells. However, when the cells possessed only 3% and 0.2% of their original mtDNA content, tumour formation was less frequent and the initiation of tumorigenesis was significantly delayed. Importantly, the process of tumorigenesis was dependent on mtDNA copy number being restored to pre-depletion levels. Results By performing whole genome MeDIP-Seq and RNA-Seq on tumours generated from cells possessing 100%, 50%, 0.3% and 0.2% of their original mtDNA content, we determined that restoration of mtDNA copy number caused significant changes to both the nuclear methylome and its transcriptome for each tumour type. The affected genes were specifically associated with gene networks and pathways involving behaviour, nervous system development, cell differentiation and regulation of transcription and cellular processes. The mtDNA-specific replication factors were also modulated. Conclusions Our results highlight the bidirectional control of the nuclear and mitochondrial genomes through modulation of DNA methylation to control mtDNA copy number, which, in turn, modulates nuclear gene expression during tumorigenesis. Electronic supplementary material The online version of this article (10.1186/s13072-018-0223-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xin Sun
- Mitochondrial Genetics Group, Hudson Institute of Medical Research, 27-31 Wright Street, Clayton, VIC, 3168, Australia.,Department of Molecular and Translational Sciences, Monash University, 27-31 Wright Street, Clayton, VIC, 3168, Australia
| | - Justin C St John
- Mitochondrial Genetics Group, Hudson Institute of Medical Research, 27-31 Wright Street, Clayton, VIC, 3168, Australia. .,Department of Molecular and Translational Sciences, Monash University, 27-31 Wright Street, Clayton, VIC, 3168, Australia.
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30
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Wideman JG, Balacco DL, Fieblinger T, Richards TA. PDZD8 is not the 'functional ortholog' of Mmm1, it is a paralog. F1000Res 2018; 7:1088. [PMID: 30109028 PMCID: PMC6069729 DOI: 10.12688/f1000research.15523.1] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 07/06/2018] [Indexed: 11/20/2022] Open
Abstract
Authors of a recent paper demonstrate that, like ERMES (ER-mitochondria encounter structure) in fungal cells, PDZD8 (PDZ domain containing 8) tethers mitochondria to the ER in mammalian cells. However, identifying PDZD8 as a "functional ortholog" of yeast Mmm1 (maintenance of mitochondrial morphology protein 1) is at odds with the phylogenetic data. PDZD8 and Mmm1 are paralogs, not orthologs, which affects the interpretation of the data with respect to the evolution of ER-mitochondria tethering. Our phylogenetic analyses show that PDZD8 co-occurs with ERMES components in lineages closely related to animals solidifying its identity as a paralog of Mmm1. Additionally, we identify two related paralogs, one specific to flagellated fungi, and one present only in unicellular relatives of animals. These results point to a complex evolutionary history of ER-mitochondria tethering involving multiple gene gains and losses in the lineage leading to animals and fungi.
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Affiliation(s)
- Jeremy G Wideman
- Department of Biosciences, University of Exeter, Exeter, EX4 4QD, UK.,Wissenschaftskolleg zu Berlin, Berlin, 14193, Germany
| | - Dario L Balacco
- School of Life Sciences, University of Nottingham, Nottingham, NG7 2UH, UK
| | - Tim Fieblinger
- Wissenschaftskolleg zu Berlin, Berlin, 14193, Germany.,Basal Ganglia Pathophysiology Unit, Department of Experimental Medical Science, Lund University, Lund, 22184, Sweden
| | - Thomas A Richards
- Department of Biosciences, University of Exeter, Exeter, EX4 4QD, UK
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31
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Kay LJ, Sangal V, Black GW, Soundararajan M. Proteomics and bioinformatics analyses identify novel cellular roles outside mitochondrial function for human miro GTPases. Mol Cell Biochem 2018; 451:21-35. [PMID: 29943371 PMCID: PMC6342832 DOI: 10.1007/s11010-018-3389-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 06/16/2018] [Indexed: 12/03/2022]
Abstract
The human Miro GTPases (hMiros) have recently emerged as important mediators of mitochondrial transport and may significantly contribute to the development of disorders such as Alzheimer’s and schizophrenia. The hMiros represent two highly atypical members of the Ras superfamily, and exhibit several unique features: the presence of a GTPase domain at both the N-terminus and C-terminus, the presence of two calcium-binding EF-hand domains and localisation to the mitochondrial outer membrane. Here, elucidation of Miro GTPase signalling pathway components was achieved through the use of molecular biology, cell culture techniques and proteomics. An investigation of this kind has not been performed previously; we hoped, through these techniques, to enable the profiling and identification of pathways regulated by the human Miro GTPases. The results indicate several novel putative interaction partners for hMiro1 and hMiro2, including numerous proteins previously implicated in neurodegenerative pathways and the development of schizophrenia. Furthermore, we show that the N-terminal GTPase domain appears to fine-tune hMiro signalling, with GTP-bound versions of this domain associated with a diverse range of interaction partners in comparison to corresponding GDP-bound versions. Recent evidences suggest that human Miros participate in host–pathogen interactions with Vibrio Cholerae type III secretion proteins. We have undertaken a bioinformatics investigation to identify novel pathogenic effectors that might interact with Miros.
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Affiliation(s)
- Laura J Kay
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, NE1 8ST, UK
| | - Vartul Sangal
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, NE1 8ST, UK
| | - Gary W Black
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, NE1 8ST, UK
| | - Meera Soundararajan
- Department of Applied Sciences, Faculty of Health and Life Sciences, Northumbria University, Newcastle, NE1 8ST, UK.
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32
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Understanding Miro GTPases: Implications in the Treatment of Neurodegenerative Disorders. Mol Neurobiol 2018; 55:7352-7365. [PMID: 29411264 PMCID: PMC6096957 DOI: 10.1007/s12035-018-0927-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 01/24/2018] [Indexed: 12/19/2022]
Abstract
The Miro GTPases represent an unusual subgroup of the Ras superfamily and have recently emerged as important mediators of mitochondrial dynamics and for maintaining neuronal health. It is now well-established that these enzymes act as essential components of a Ca2+-sensitive motor complex, facilitating the transport of mitochondria along microtubules in several cell types, including dopaminergic neurons. The Miros appear to be critical for both anterograde and retrograde mitochondrial transport in axons and dendrites, both of which are considered essential for neuronal health. Furthermore, the Miros may be significantly involved in the development of several serious pathological processes, including the development of neurodegenerative and psychiatric disorders. In this review, we discuss the molecular structure and known mitochondrial functions of the Miro GTPases in humans and other organisms, in the context of neurodegenerative disease. Finally, we consider the potential human Miros hold as novel therapeutic targets for the treatment of such disease.
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33
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Shenoy AR, Furniss RCD, Goddard PJ, Clements A. Modulation of Host Cell Processes by T3SS Effectors. Curr Top Microbiol Immunol 2018; 416:73-115. [PMID: 30178263 DOI: 10.1007/82_2018_106] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Two of the enteric Escherichia coli pathotypes-enteropathogenic E. coli (EPEC) and enterohaemorrhagic E. coli (EHEC)-have a conserved type 3 secretion system which is essential for virulence. The T3SS is used to translocate between 25 and 50 bacterial proteins directly into the host cytosol where they manipulate a variety of host cell processes to establish a successful infection. In this chapter, we discuss effectors from EPEC/EHEC in the context of the host proteins and processes that they target-the actin cytoskeleton, small guanosine triphosphatases and innate immune signalling pathways that regulate inflammation and cell death. Many of these translocated proteins have been extensively characterised, which has helped obtain insights into the mechanisms of pathogenesis of these bacteria and also understand the host pathways they target in more detail. With increasing knowledge of the positive and negative regulation of host signalling pathways by different effectors, a future challenge is to investigate how the specific effector repertoire of each strain cooperates over the course of an infection.
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Affiliation(s)
- Avinash R Shenoy
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - R Christopher D Furniss
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - Philippa J Goddard
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK
| | - Abigail Clements
- MRC Centre for Molecular Bacteriology and Infection, Imperial College London, Armstrong Road, SW7 2AZ, London, UK.
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34
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Intra- and Intercellular Quality Control Mechanisms of Mitochondria. Cells 2017; 7:cells7010001. [PMID: 29278362 PMCID: PMC5789274 DOI: 10.3390/cells7010001] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 12/22/2017] [Accepted: 12/23/2017] [Indexed: 12/29/2022] Open
Abstract
Mitochondria function to generate ATP and also play important roles in cellular homeostasis, signaling, apoptosis, autophagy, and metabolism. The loss of mitochondrial function results in cell death and various types of diseases. Therefore, quality control of mitochondria via intra- and intercellular pathways is crucial. Intracellular quality control consists of biogenesis, fusion and fission, and degradation of mitochondria in the cell, whereas intercellular quality control involves tunneling nanotubes and extracellular vesicles. In this review, we outline the current knowledge on the intra- and intercellular quality control mechanisms of mitochondria.
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35
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O'Mealey GB, Plafker KS, Berry WL, Janknecht R, Chan JY, Plafker SM. A PGAM5-KEAP1-Nrf2 complex is required for stress-induced mitochondrial retrograde trafficking. J Cell Sci 2017; 130:3467-3480. [PMID: 28839075 DOI: 10.1242/jcs.203216] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2017] [Accepted: 08/20/2017] [Indexed: 12/12/2022] Open
Abstract
The Nrf2 transcription factor is a master regulator of the cellular anti-stress response. A population of the transcription factor associates with the mitochondria through a complex with KEAP1 and the mitochondrial outer membrane histidine phosphatase, PGAM5. To determine the function of this mitochondrial complex, we knocked down each component and assessed mitochondrial morphology and distribution. We discovered that depletion of Nrf2 or PGAM5, but not KEAP1, inhibits mitochondrial retrograde trafficking induced by proteasome inhibition. Mechanistically, this disrupted motility results from aberrant degradation of Miro2, a mitochondrial GTPase that links mitochondria to microtubules. Rescue experiments demonstrate that this Miro2 degradation involves the KEAP1-cullin-3 E3 ubiquitin ligase and the proteasome. These data are consistent with a model in which an intact complex of PGAM5-KEAP1-Nrf2 preserves mitochondrial motility by suppressing dominant-negative KEAP1 activity. These data further provide a mechanistic explanation for how age-dependent declines in Nrf2 expression impact mitochondrial motility and induce functional deficits commonly linked to neurodegeneration.
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Affiliation(s)
- Gary B O'Mealey
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73118, USA.,Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73118, USA
| | - Kendra S Plafker
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73118, USA
| | - William L Berry
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73118, USA
| | - Ralf Janknecht
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73118, USA
| | - Jefferson Y Chan
- Department of Pathology, University of Irvine School of Medicine, Irvine, CA 92697, USA
| | - Scott M Plafker
- Aging and Metabolism Research Program, Oklahoma Medical Research Foundation, Oklahoma City, OK 73118, USA
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36
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Compartmentalized Regulation of Parkin-Mediated Mitochondrial Quality Control in the Drosophila Nervous System In Vivo. J Neurosci 2017; 36:7375-91. [PMID: 27413149 DOI: 10.1523/jneurosci.0633-16.2016] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 05/18/2016] [Indexed: 12/14/2022] Open
Abstract
UNLABELLED In neurons, the normal distribution and selective removal of mitochondria are considered essential for maintaining the functions of the large asymmetric cell and its diverse compartments. Parkin, a E3 ubiquitin ligase associated with familial Parkinson's disease, has been implicated in mitochondrial dynamics and removal in cells including neurons. However, it is not clear how Parkin functions in mitochondrial turnover in vivo, or whether Parkin-dependent events of the mitochondrial life cycle occur in all neuronal compartments. Here, using the live Drosophila nervous system, we investigated the involvement of Parkin in mitochondrial dynamics, distribution, morphology, and removal. Contrary to our expectations, we found that Parkin-deficient animals do not accumulate senescent mitochondria in their motor axons or neuromuscular junctions; instead, they contain far fewer axonal mitochondria, and these displayed normal motility behavior, morphology, and metabolic state. However, the loss of Parkin did produce abnormal tubular and reticular mitochondria restricted to the motor cell bodies. In addition, in contrast to drug-treated, immortalized cells in vitro, mature motor neurons rarely displayed Parkin-dependent mitophagy. These data indicate that the cell body is the focus of Parkin-dependent mitochondrial quality control in neurons, and argue that a selection process allows only healthy mitochondria to pass from cell bodies to axons, perhaps to limit the impact of mitochondrial dysfunction. SIGNIFICANCE STATEMENT Parkin has been proposed to police mitochondrial fidelity by binding to dysfunctional mitochondria via PTEN (phosphatase and tensin homolog)-induced putative kinase 1 (PINK1) and targeting them for autophagic degradation. However, it is unknown whether and how the PINK1/Parkin pathway regulates the mitochondrial life cycle in neurons in vivo Using Drosophila motor neurons, we show that parkin disruption generates an abnormal mitochondrial network in cell bodies in vivo and reduces the number of axonal mitochondria without producing any defects in their axonal transport, morphology, or metabolic state. Furthermore, while cultured neurons display Parkin-dependent axonal mitophagy, we find this is vanishingly rare in vivo under normal physiological conditions. Thus, both the spatial distribution and mechanism of mitochondrial quality control in vivo differ substantially from those observed in vitro.
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Mitochondria-organelle contact sites: the plot thickens. Biochem Soc Trans 2017; 45:477-488. [PMID: 28408488 DOI: 10.1042/bst20160130] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Revised: 02/07/2017] [Accepted: 02/13/2017] [Indexed: 01/30/2023]
Abstract
Membrane contact sites (MCSs) are areas of close apposition between the membranes of two different organelles that enable non-vesicular transfer of ions and lipids. Recent studies reveal that mitochondria maintain contact sites with organelles other than the endoplasmic reticulum such as the vacuole, plasma membrane and peroxisomes. This review focuses on novel findings achieved mainly in yeast regarding tethers, function and regulation of mitochondria-organelle contact sites. The emerging network of MCSs linking virtually all cellular organelles is highly dynamic and integrated with cellular metabolism.
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Francis JW, Turn RE, Newman LE, Schiavon C, Kahn RA. Higher order signaling: ARL2 as regulator of both mitochondrial fusion and microtubule dynamics allows integration of 2 essential cell functions. Small GTPases 2016; 7:188-196. [PMID: 27400436 PMCID: PMC5129891 DOI: 10.1080/21541248.2016.1211069] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 07/05/2016] [Accepted: 07/06/2016] [Indexed: 10/21/2022] Open
Abstract
ARL2 is among the most highly conserved proteins, predicted to be present in the last eukaryotic common ancestor, and ubiquitously expressed. Genetic screens in multiple model organisms identified ARL2, and its cytosolic binding partner cofactor D (TBCD), as important in tubulin folding and microtubule dynamics. Both ARL2 and TBCD also localize to centrosomes, making it difficult to dissect these effects. A growing body of evidence also has found roles for ARL2 inside mitochondria, as a regulator of mitochondrial fusion. Other studies have revealed roles for ARL2, in concert with its closest paralog ARL3, in the traffic of farnesylated cargos between membranes and specifically to cilia and photoreceptor cells. Details of each of these signaling processes continue to emerge. We summarize those data here and speculate about the potential for cross-talk or coordination of cell regulation, termed higher order signaling, based upon the use of a common GTPase in disparate cell functions.
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Affiliation(s)
- Joshua W. Francis
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Rachel E. Turn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Laura E. Newman
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Cara Schiavon
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
| | - Richard A. Kahn
- Department of Biochemistry, Emory University School of Medicine, Atlanta, GA, USA
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Fielden LF, Kang Y, Newton HJ, Stojanovski D. Targeting mitochondria: how intravacuolar bacterial pathogens manipulate mitochondria. Cell Tissue Res 2016; 367:141-154. [PMID: 27515462 DOI: 10.1007/s00441-016-2475-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2016] [Accepted: 07/07/2016] [Indexed: 02/07/2023]
Abstract
Manipulation of host cell function by bacterial pathogens is paramount for successful invasion and creation of a niche conducive to bacterial replication. Mitochondria play a role in many important cellular processes including energy production, cellular calcium homeostasis, lipid metabolism, haeme biosynthesis, immune signalling and apoptosis. The sophisticated integration of host cell processes by the mitochondrion have seen it emerge as a key target during bacterial infection of human host cells. This review highlights the targeting and interaction of this dynamic organelle by intravacuolar bacterial pathogens and the way that the modulation of mitochondrial function might contribute to pathogenesis.
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Affiliation(s)
- Laura F Fielden
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Yilin Kang
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Hayley J Newton
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Parkville, VIC, 3000, Australia.
| | - Diana Stojanovski
- Department of Biochemistry and Molecular Biology and Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, 3010, Australia.
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40
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Guan Y, Wang DY, Ying SH, Feng MG. Miro GTPase controls mitochondrial behavior affecting stress tolerance and virulence of a fungal insect pathogen. Fungal Genet Biol 2016; 93:1-9. [DOI: 10.1016/j.fgb.2016.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2016] [Revised: 05/25/2016] [Accepted: 05/26/2016] [Indexed: 10/21/2022]
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41
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Larance M, Kirkwood KJ, Tinti M, Brenes Murillo A, Ferguson MAJ, Lamond AI. Global Membrane Protein Interactome Analysis using In vivo Crosslinking and Mass Spectrometry-based Protein Correlation Profiling. Mol Cell Proteomics 2016; 15:2476-90. [PMID: 27114452 PMCID: PMC4937518 DOI: 10.1074/mcp.o115.055467] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 03/11/2016] [Indexed: 12/30/2022] Open
Abstract
We present a methodology using in vivo crosslinking combined with HPLC-MS for the global analysis of endogenous protein complexes by protein correlation profiling. Formaldehyde crosslinked protein complexes were extracted with high yield using denaturing buffers that maintained complex solubility during chromatographic separation. We show this efficiently detects both integral membrane and membrane-associated protein complexes,in addition to soluble complexes, allowing identification and analysis of complexes not accessible in native extracts. We compare the protein complexes detected by HPLC-MS protein correlation profiling in both native and formaldehyde crosslinked U2OS cell extracts. These proteome-wide data sets of both in vivo crosslinked and native protein complexes from U2OS cells are freely available via a searchable online database (www.peptracker.com/epd). Raw data are also available via ProteomeXchange (identifier PXD003754).
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Affiliation(s)
- Mark Larance
- From the ‡Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Kathryn J Kirkwood
- From the ‡Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Michele Tinti
- §Biological Chemistry and Drug Discovery Division, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Alejandro Brenes Murillo
- From the ‡Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Michael A J Ferguson
- §Biological Chemistry and Drug Discovery Division, School of Life Sciences, University of Dundee, Dundee, United Kingdom
| | - Angus I Lamond
- From the ‡Centre for Gene Regulation and Expression, School of Life Sciences, University of Dundee, Dundee, United Kingdom;
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42
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Paul P, Röth S, Schleiff E. Importance of organellar proteins, protein translocation and vesicle transport routes for pollen development and function. PLANT REPRODUCTION 2016; 29:53-65. [PMID: 26874709 DOI: 10.1007/s00497-016-0274-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 01/18/2016] [Indexed: 05/27/2023]
Abstract
Protein translocation. Cellular homeostasis strongly depends on proper distribution of proteins within cells and insertion of membrane proteins into the destined membranes. The latter is mediated by organellar protein translocation and the complex vesicle transport system. Considering the importance of protein transport machineries in general it is foreseen that these processes are essential for pollen function and development. However, the information available in this context is very scarce because of the current focus on deciphering the fundamental principles of protein transport at the molecular level. Here we review the significance of protein transport machineries for pollen development on the basis of pollen-specific organellar proteins as well as of genetic studies utilizing mutants of known organellar proteins. In many cases these mutants exhibit morphological alterations highlighting the requirement of efficient protein transport and translocation in pollen. Furthermore, expression patterns of genes coding for translocon subunits and vesicle transport factors in Arabidopsis thaliana are summarized. We conclude that with the exception of the translocation systems in plastids-the composition and significance of the individual transport systems are equally important in pollen as in other cell types. Apparently for plastids only a minimal translocon, composed of only few subunits, exists in the envelope membranes during maturation of pollen. However, only one of the various transport systems known from thylakoids seems to be required for the function of the "simple thylakoid system" existing in pollen plastids. In turn, the vesicle transport system is as complex as seen for other cell types as it is essential, e.g., for pollen tube formation.
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Affiliation(s)
- Puneet Paul
- Department of Biosciences, Molecular Cell Biology of Plants, Goethe University, 60438, Frankfurt Am Main, Germany
| | - Sascha Röth
- Department of Biosciences, Molecular Cell Biology of Plants, Goethe University, 60438, Frankfurt Am Main, Germany
| | - Enrico Schleiff
- Department of Biosciences, Molecular Cell Biology of Plants, Goethe University, 60438, Frankfurt Am Main, Germany.
- Cluster of Excellence Frankfurt, Goethe University, 60438, Frankfurt Am Main, Germany.
- Buchmann Institute for Molecular Life Sciences (BMLS), Goethe University, 60438, Frankfurt Am Main, Germany.
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43
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Liang Q, Kobayashi S. Mitochondrial quality control in the diabetic heart. J Mol Cell Cardiol 2016; 95:57-69. [PMID: 26739215 PMCID: PMC6263145 DOI: 10.1016/j.yjmcc.2015.12.025] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 12/03/2015] [Accepted: 12/26/2015] [Indexed: 02/07/2023]
Abstract
Diabetes is a well-known risk factor for heart failure. Diabetic heart damage is closely related to mitochondrial dysfunction and increased ROS generation. However, clinical trials have shown no effects of antioxidant therapies on heart failure in diabetic patients, suggesting that simply antagonizing existing ROS by antioxidants is not sufficient to reduce diabetic cardiac injury. A potentially more effective treatment strategy may be to enhance the overall capacity of mitochondrial quality control to maintain a pool of healthy mitochondria that are needed for supporting cardiac contractile function in diabetic patients. Mitochondrial quality is controlled by a number of coordinated mechanisms including mitochondrial fission and fusion, mitophagy and biogenesis. The mitochondrial damage consistently observed in the diabetic hearts indicates a failure of the mitochondrial quality control mechanisms. Recent studies have demonstrated a crucial role for each of these mechanisms in cardiac homeostasis and have begun to interrogate the relative contribution of insufficient mitochondrial quality control to diabetic cardiac injury. In this review, we will present currently available literature that links diabetic heart disease to the dysregulation of major mitochondrial quality control mechanisms. We will discuss the functional roles of these mechanisms in the pathogenesis of diabetic heart disease and their potentials for targeted therapeutical manipulation.
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Affiliation(s)
- Qiangrong Liang
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA.
| | - Satoru Kobayashi
- Department of Biomedical Sciences, New York Institute of Technology College of Osteopathic Medicine, Old Westbury, NY, USA
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Schmoll M, Dattenböck C, Carreras-Villaseñor N, Mendoza-Mendoza A, Tisch D, Alemán MI, Baker SE, Brown C, Cervantes-Badillo MG, Cetz-Chel J, Cristobal-Mondragon GR, Delaye L, Esquivel-Naranjo EU, Frischmann A, Gallardo-Negrete JDJ, García-Esquivel M, Gomez-Rodriguez EY, Greenwood DR, Hernández-Oñate M, Kruszewska JS, Lawry R, Mora-Montes HM, Muñoz-Centeno T, Nieto-Jacobo MF, Nogueira Lopez G, Olmedo-Monfil V, Osorio-Concepcion M, Piłsyk S, Pomraning KR, Rodriguez-Iglesias A, Rosales-Saavedra MT, Sánchez-Arreguín JA, Seidl-Seiboth V, Stewart A, Uresti-Rivera EE, Wang CL, Wang TF, Zeilinger S, Casas-Flores S, Herrera-Estrella A. The Genomes of Three Uneven Siblings: Footprints of the Lifestyles of Three Trichoderma Species. Microbiol Mol Biol Rev 2016; 80:205-327. [PMID: 26864432 PMCID: PMC4771370 DOI: 10.1128/mmbr.00040-15] [Citation(s) in RCA: 125] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genus Trichoderma contains fungi with high relevance for humans, with applications in enzyme production for plant cell wall degradation and use in biocontrol. Here, we provide a broad, comprehensive overview of the genomic content of these species for "hot topic" research aspects, including CAZymes, transport, transcription factors, and development, along with a detailed analysis and annotation of less-studied topics, such as signal transduction, genome integrity, chromatin, photobiology, or lipid, sulfur, and nitrogen metabolism in T. reesei, T. atroviride, and T. virens, and we open up new perspectives to those topics discussed previously. In total, we covered more than 2,000 of the predicted 9,000 to 11,000 genes of each Trichoderma species discussed, which is >20% of the respective gene content. Additionally, we considered available transcriptome data for the annotated genes. Highlights of our analyses include overall carbohydrate cleavage preferences due to the different genomic contents and regulation of the respective genes. We found light regulation of many sulfur metabolic genes. Additionally, a new Golgi 1,2-mannosidase likely involved in N-linked glycosylation was detected, as were indications for the ability of Trichoderma spp. to generate hybrid galactose-containing N-linked glycans. The genomic inventory of effector proteins revealed numerous compounds unique to Trichoderma, and these warrant further investigation. We found interesting expansions in the Trichoderma genus in several signaling pathways, such as G-protein-coupled receptors, RAS GTPases, and casein kinases. A particularly interesting feature absolutely unique to T. atroviride is the duplication of the alternative sulfur amino acid synthesis pathway.
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Affiliation(s)
- Monika Schmoll
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | - Christoph Dattenböck
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Doris Tisch
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | - Mario Ivan Alemán
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | - Scott E Baker
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Christopher Brown
- University of Otago, Department of Biochemistry and Genetics, Dunedin, New Zealand
| | | | - José Cetz-Chel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - Luis Delaye
- Cinvestav, Department of Genetic Engineering, Irapuato, Guanajuato, Mexico
| | | | - Alexa Frischmann
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | - Monica García-Esquivel
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | | | - David R Greenwood
- The University of Auckland, School of Biological Sciences, Auckland, New Zealand
| | - Miguel Hernández-Oñate
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
| | - Joanna S Kruszewska
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Robert Lawry
- Lincoln University, Bio-Protection Research Centre, Lincoln, Canterbury, New Zealand
| | | | | | | | | | | | | | - Sebastian Piłsyk
- Polish Academy of Sciences, Institute of Biochemistry and Biophysics, Laboratory of Fungal Glycobiology, Warsaw, Poland
| | - Kyle R Pomraning
- Pacific Northwest National Laboratory, Richland, Washington, USA
| | - Aroa Rodriguez-Iglesias
- Austrian Institute of Technology, Department Health and Environment, Bioresources Unit, Tulln, Austria
| | | | | | - Verena Seidl-Seiboth
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria
| | | | | | - Chih-Li Wang
- National Chung-Hsing University, Department of Plant Pathology, Taichung, Taiwan
| | - Ting-Fang Wang
- Academia Sinica, Institute of Molecular Biology, Taipei, Taiwan
| | - Susanne Zeilinger
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, TU Wien, Vienna, Austria University of Innsbruck, Institute of Microbiology, Innsbruck, Austria
| | | | - Alfredo Herrera-Estrella
- LANGEBIO, National Laboratory of Genomics for Biodiversity, Cinvestav-Irapuato, Guanajuato, Mexico
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Cross Talk of Proteostasis and Mitostasis in Cellular Homeodynamics, Ageing, and Disease. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2016; 2016:4587691. [PMID: 26977249 PMCID: PMC4763003 DOI: 10.1155/2016/4587691] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Revised: 12/24/2015] [Accepted: 12/31/2015] [Indexed: 12/26/2022]
Abstract
Mitochondria are highly dynamic organelles that provide essential metabolic functions and represent the major bioenergetic hub of eukaryotic cell. Therefore, maintenance of mitochondria activity is necessary for the proper cellular function and survival. To this end, several mechanisms that act at different levels and time points have been developed to ensure mitochondria quality control. An interconnected highly integrated system of mitochondrial and cytosolic chaperones and proteases along with the fission/fusion machinery represents the surveillance scaffold of mitostasis. Moreover, nonreversible mitochondrial damage targets the organelle to a specific autophagic removal, namely, mitophagy. Beyond the organelle dynamics, the constant interaction with the ubiquitin-proteasome-system (UPS) has become an emerging aspect of healthy mitochondria. Dysfunction of mitochondria and UPS increases with age and correlates with many age-related diseases including cancer and neurodegeneration. In this review, we discuss the functional cross talk of proteostasis and mitostasis in cellular homeodynamics and the impairment of mitochondrial quality control during ageing, cancer, and neurodegeneration.
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Characterization of the three zebrafish orthologs of the mitochondrial GTPase Miro/Rhot. Comp Biochem Physiol B Biochem Mol Biol 2016; 191:126-34. [DOI: 10.1016/j.cbpb.2015.10.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 10/14/2015] [Accepted: 10/14/2015] [Indexed: 01/02/2023]
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The Rho GTPase Family Genes in Bivalvia Genomes: Sequence, Evolution and Expression Analysis. PLoS One 2015; 10:e0143932. [PMID: 26633655 PMCID: PMC4669188 DOI: 10.1371/journal.pone.0143932] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 11/11/2015] [Indexed: 01/27/2023] Open
Abstract
Background Rho GTPases are important members of the Ras superfamily, which represents the largest signaling protein family in eukaryotes, and function as key molecular switches in converting and amplifying external signals into cellular responses. Although numerous analyses of Rho family genes have been reported, including their functions and evolution, a systematic analysis of this family has not been performed in Mollusca or in Bivalvia, one of the most important classes of Mollusca. Results In this study, we systematically identified and characterized a total set (Rho, Rac, Mig, Cdc42, Tc10, Rnd, RhoU, RhoBTB and Miro) of thirty Rho GTPase genes in three bivalve species, including nine in the Yesso scallop Patinopecten yessoensis, nine in the Zhikong scallop Chlamys farreri, and twelve in the Pacific oyster Crassostrea gigas. Phylogenetic analysis and interspecies comparison indicated that bivalves might possess the most complete types of Rho genes in invertebrates. A multiple RNA-seq dataset was used to investigate the expression profiles of bivalve Rho genes, revealing that the examined scallops share more similar Rho expression patterns than the oyster, whereas more Rho mRNAs are expressed in C. farreri and C. gigas than in P. yessoensis. Additionally, Rho, Rac and Cdc42 were found to be duplicated in the oyster but not in the scallops. Among the expanded Rho genes of C. gigas, duplication pairs with high synonymous substitution rates (Ks) displayed greater differences in expression. Conclusion A comprehensive analysis of bivalve Rho GTPase family genes was performed in scallop and oyster species, and Rho genes in bivalves exhibit greater conservation than those in any other invertebrate. This is the first study focusing on a genome-wide characterization of Rho GTPase genes in bivalves, and the findings will provide a valuable resource for a better understanding of Rho evolution and Rho GTPase function in Bivalvia.
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Miro's N-terminal GTPase domain is required for transport of mitochondria into axons and dendrites. J Neurosci 2015; 35:5754-71. [PMID: 25855186 DOI: 10.1523/jneurosci.1035-14.2015] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Mitochondria are dynamically transported in and out of neuronal processes to maintain neuronal excitability and synaptic function. In higher eukaryotes, the mitochondrial GTPase Miro binds Milton/TRAK adaptor proteins linking microtubule motors to mitochondria. Here we show that Drosophila Miro (dMiro), which has previously been shown to be required for kinesin-driven axonal transport, is also critically required for the dynein-driven distribution of mitochondria into dendrites. In addition, we used the loss-of-function mutations dMiroT25N and dMiroT460N to determine the significance of dMiro's N-terminal and C-terminal GTPase domains, respectively. Expression of dMiroT25N in the absence of endogenous dMiro caused premature lethality and arrested development at a pupal stage. dMiroT25N accumulated mitochondria in the soma of larval motor and sensory neurons, and prevented their kinesin-dependent and dynein-dependent distribution into axons and dendrites, respectively. dMiroT25N mutant mitochondria also were severely fragmented and exhibited reduced kinesin and dynein motility in axons. In contrast, dMiroT460N did not impair viability, mitochondrial size, or the distribution of mitochondria. However, dMiroT460N reduced dynein motility during retrograde mitochondrial transport in axons. Finally, we show that substitutions analogous to the constitutively active Ras-G12V mutation in dMiro's N-terminal and C-terminal GTPase domains cause neomorphic phenotypic effects that are likely unrelated to the normal function of each GTPase domain. Overall, our analysis indicates that dMiro's N-terminal GTPase domain is critically required for viability, mitochondrial size, and the distribution of mitochondria out of the neuronal soma regardless of the employed motor, likely by promoting the transition from a stationary to a motile state.
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Vibrio cholerae T3SS effector VopE modulates mitochondrial dynamics and innate immune signaling by targeting Miro GTPases. Cell Host Microbe 2014; 16:581-91. [PMID: 25450857 DOI: 10.1016/j.chom.2014.09.015] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Revised: 08/25/2014] [Accepted: 09/16/2014] [Indexed: 01/14/2023]
Abstract
The cellular surveillance-activated detoxification and defenses (cSADD) theory postulates the presence of host surveillance mechanisms that monitor the integrity of common cellular processes and components targeted by pathogen effectors. Being organelles essential for multiple cellular processes, including innate immune responses, mitochondria represent an attractive target for pathogens. We describe a Vibrio cholerae Type 3 secretion system effector VopE that localizes to mitochondria during infection and acts as a specific GTPase-activating protein to interfere with the function of mitochondrial Rho GTPases Miro1 and Miro2. Miro GTPases modulate mitochondrial dynamics and interfering with this functionality effectively blocks innate immune responses that presumably require mitochondria as signaling platforms. Our data indicate that interference with mitochondrial dynamics may be an unappreciated strategy that pathogens use to block host innate immune responses that would otherwise control these bacterial infections. VopE might represent a bacterial effector that targets the cSADD surveillance response.
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50
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Yamaoka S, Hara-Nishimura I. The mitochondrial Ras-related GTPase Miro: views from inside and outside the metazoan kingdom. FRONTIERS IN PLANT SCIENCE 2014; 5:350. [PMID: 25076955 PMCID: PMC4100572 DOI: 10.3389/fpls.2014.00350] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 06/30/2014] [Indexed: 05/24/2023]
Abstract
Miro GTPase, a member of the Ras superfamily, consists of two GTPase domains flanking a pair of EF hand motifs and a C-terminal transmembrane domain that anchors the protein to the mitochondrial outer membrane. Since the identification of Miro in humans, a series of studies in metazoans, including mammals and fruit flies, have shown that Miro plays a role in the calcium-dependent regulation of mitochondrial transport along microtubules. However, in non-metazoans, including yeasts, slime molds, and plants, Miro is primarily involved in the maintenance of mitochondrial morphology and homeostasis. Given the high level of conservation of Miro in eukaryotes and the variation in the molecular mechanisms of mitochondrial transport between eukaryotic lineages, Miro may have a common ancestral function in mitochondria, and its roles in the regulation of mitochondrial transport may have been acquired specifically by metazoans after the evolutionary divergence of eukaryotes.
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Affiliation(s)
- Shohei Yamaoka
- Graduate School of Biostudies, Kyoto UniversityKyoto, Japan
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