51
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Carrascoso I, Velasco BR, Izquierdo JM. Deficiency of T-Cell Intracellular Antigen 1 in Murine Embryonic Fibroblasts Is Associated with Changes in Mitochondrial Morphology and Respiration. Int J Mol Sci 2021; 22:ijms222312775. [PMID: 34884582 PMCID: PMC8657690 DOI: 10.3390/ijms222312775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 11/22/2021] [Accepted: 11/24/2021] [Indexed: 01/14/2023] Open
Abstract
T-cell intracellular antigen 1 (TIA1) is a multifunctional RNA-binding protein involved in regulating gene expression and splicing during development and in response to environmental stress, to maintain cell homeostasis and promote survival. Herein, we used TIA1-deficient murine embryonic fibroblasts (MEFs) to study their role in mitochondria homeostasis. We found that the loss of TIA1 was associated with changes in mitochondrial morphology, promoting the appearance of elongated mitochondria with heterogeneous cristae density and size. The proteomic patterns of TIA1-deficient MEFs were consistent with expression changes in molecular components related to mitochondrial dynamics/organization and respiration. Bioenergetics analysis illustrated that TIA1 deficiency enhances mitochondrial respiration. Overall, our findings shed light on the role of TIA1 in mitochondrial dynamics and highlight a point of crosstalk between potential pro-survival and pro-senescence pathways.
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52
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Chan D, Feng C, England WE, Wyman D, Flynn R, Wang X, Shi Y, Mortazavi A, Spitale R. Diverse functional elements in RNA predicted transcriptome-wide by orthogonal RNA structure probing. Nucleic Acids Res 2021; 49:11868-11882. [PMID: 34634799 PMCID: PMC8599799 DOI: 10.1093/nar/gkab885] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/15/2021] [Accepted: 09/20/2021] [Indexed: 01/02/2023] Open
Abstract
RNA molecules can fold into complex structures and interact with trans-acting factors to control their biology. Recent methods have been focused on developing novel tools to measure RNA structure transcriptome-wide, but their utility to study and predict RNA-protein interactions or RNA processing has been limited thus far. Here, we extend these studies with the first transcriptome-wide mapping method for cataloging RNA solvent accessibility, icLASER. By combining solvent accessibility (icLASER) with RNA flexibility (icSHAPE) data, we efficiently predict RNA-protein interactions transcriptome-wide and catalog RNA polyadenylation sites by RNA structure alone. These studies showcase the power of designing novel chemical approaches to studying RNA biology. Further, our study exemplifies merging complementary methods to measure RNA structure inside cells and its utility for predicting transcriptome-wide interactions that are critical for control of and regulation by RNA structure. We envision such approaches can be applied to studying different cell types or cells under varying conditions, using RNA structure and footprinting to characterize cellular interactions and processing involving RNA.
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Affiliation(s)
- Dalen Chan
- Department of Pharmaceutical Sciences, University of California, Irvine. Irvine, CA 92697, USA
| | - Chao Feng
- Department of Pharmaceutical Sciences, University of California, Irvine. Irvine, CA 92697, USA
| | - Whitney E England
- Department of Pharmaceutical Sciences, University of California, Irvine. Irvine, CA 92697, USA
| | - Dana Wyman
- Department of Developmental and Cellular Biology, University of California, Irvine. Irvine, CA 92697, USA
| | - Ryan A Flynn
- Stem Cell Program, Boston Children’s Hospital, Boston, MA, USA and Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA, USA
| | - Xiuye Wang
- Department Microbiology and Molecular Genetics, University of California, Irvine. Irvine, CA 92697, USA
| | - Yongsheng Shi
- Department Microbiology and Molecular Genetics, University of California, Irvine. Irvine, CA 92697, USA
| | - Ali Mortazavi
- Department of Developmental and Cellular Biology, University of California, Irvine. Irvine, CA 92697, USA
| | - Robert C Spitale
- Department of Pharmaceutical Sciences, University of California, Irvine. Irvine, CA 92697, USA
- Department of Chemistry, University of California, Irvine. Irvine, CA 92697, USA
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53
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Lechado Terradas A, Zittlau KI, Macek B, Fraiberg M, Elazar Z, Kahle PJ. Regulation of mitochondrial cargo-selective autophagy by posttranslational modifications. J Biol Chem 2021; 297:101339. [PMID: 34688664 PMCID: PMC8591368 DOI: 10.1016/j.jbc.2021.101339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/14/2021] [Accepted: 10/20/2021] [Indexed: 12/18/2022] Open
Abstract
Mitochondria are important organelles in eukaryotes. Turnover and quality control of mitochondria are regulated at the transcriptional and posttranslational level by several cellular mechanisms. Removal of defective mitochondrial proteins is mediated by mitochondria resident proteases or by proteasomal degradation of individual proteins. Clearance of bulk mitochondria occurs via a selective form of autophagy termed mitophagy. In yeast and some developing metazoan cells (e.g., oocytes and reticulocytes), mitochondria are largely removed by ubiquitin-independent mechanisms. In such cases, the regulation of mitophagy is mediated via phosphorylation of mitochondria-anchored autophagy receptors. On the other hand, ubiquitin-dependent recruitment of cytosolic autophagy receptors occurs in situations of cellular stress or disease, where dysfunctional mitochondria would cause oxidative damage. In mammalian cells, a well-studied ubiquitin-dependent mitophagy pathway induced by mitochondrial depolarization is regulated by the mitochondrial protein kinase PINK1, which upon activation recruits the ubiquitin ligase parkin. Here, we review mechanisms of mitophagy with an emphasis on posttranslational modifications that regulate various mitophagy pathways. We describe the autophagy components involved with particular emphasis on posttranslational modifications. We detail the phosphorylations mediated by PINK1 and parkin-mediated ubiquitylations of mitochondrial proteins that can be modulated by deubiquitylating enzymes. We also discuss the role of accessory factors regulating mitochondrial fission/fusion and the interplay with pro- and antiapoptotic Bcl-2 family members. Comprehensive knowledge of the processes of mitophagy is essential for the understanding of vital mitochondrial turnover in health and disease.
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Affiliation(s)
- Anna Lechado Terradas
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | | | - Boris Macek
- Proteome Center Tübingen, University of Tübingen, Tübingen, Germany
| | - Milana Fraiberg
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Zvulun Elazar
- Department of Biomolecular Sciences, The Weizmann Institute of Science, Rehovot, Israel
| | - Philipp J Kahle
- Laboratory of Functional Neurogenetics, Department of Neurodegeneration, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany; Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany; German Center for Neurodegenerative Diseases (DZNE), Tübingen, Germany.
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54
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Belser M, Walker DW. Role of Prohibitins in Aging and Therapeutic Potential Against Age-Related Diseases. Front Genet 2021; 12:714228. [PMID: 34868199 PMCID: PMC8636131 DOI: 10.3389/fgene.2021.714228] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Accepted: 09/21/2021] [Indexed: 12/16/2022] Open
Abstract
A decline in mitochondrial function has long been associated with age-related health decline. Several lines of evidence suggest that interventions that stimulate mitochondrial autophagy (mitophagy) can slow aging and prolong healthy lifespan. Prohibitins (PHB1 and PHB2) assemble at the mitochondrial inner membrane and are critical for mitochondrial homeostasis. In addition, prohibitins (PHBs) have diverse roles in cell and organismal biology. Here, we will discuss the role of PHBs in mitophagy, oxidative phosphorylation, cellular senescence, and apoptosis. We will also discuss the role of PHBs in modulating lifespan. In addition, we will review the links between PHBs and diseases of aging. Finally, we will discuss the emerging concept that PHBs may represent an attractive therapeutic target to counteract aging and age-onset disease.
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Affiliation(s)
- Misa Belser
- Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, Los Angeles, CA, United States
| | - David W. Walker
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA, United States
- Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA, United States
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55
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Romani M, Auwerx J. Phalloidin Staining of Actin Filaments for Visualization of Muscle Fibers in Caenorhabditis elegans. Bio Protoc 2021; 11:e4183. [PMID: 34722829 PMCID: PMC8517648 DOI: 10.21769/bioprotoc.4183] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Revised: 06/25/2021] [Accepted: 07/07/2021] [Indexed: 01/09/2023] Open
Abstract
Advances in C. elegans research have allowed scientists to recapitulate different human disorders, from neurodegenerative diseases to muscle dysfunction, in these nematodes. Concomitantly, the interest in visualizing organs affected by these conditions has grown, leading to the establishment of different antibody- and dye-based staining protocols to verify tissue morphology. In particular, the quality of muscle tissue has been largely used in nematodes as a readout for fitness and healthspan. Phalloidin derivatives, which are commonly used to stain actin filaments in cells and tissues, have been implemented in the context of C. elegans research for visualization of muscle fibers. However, the majority of the phalloidin-based protocols depend on fixation steps using harmful compounds, preparation of specific buffers, and large amounts of worms. Herein, we implemented a safer and more flexible experimental procedure to stain actin filaments in C. elegans using phalloidin-based dyes. Lyophilization of the worms followed by their acetone permeabilization allows bypassing the fixation process while also providing the opportunity to suspend the experiment at different steps. Moreover, by using conventional buffers throughout our protocol, we avoid the additional preparation of solutions. Finally, our protocol requires a limited number of worms, making it suitable for slow-growing C. elegans strains. Overall, this protocol provides an efficient, fast, and safer method to stain actin filaments and visualize muscle fibers in C. elegans. Graphic abstract: Schematic overview of phalloidin staining in C. elegans for assessing muscle fiber morphology.
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Affiliation(s)
- Mario Romani
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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56
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Xu Z, Zhao J, Hong M, Zeng C, Guang S, Shi Y. Structural recognition of the mRNA 3' UTR by PUF-8 restricts the lifespan of C. elegans. Nucleic Acids Res 2021; 49:10082-10097. [PMID: 34478557 PMCID: PMC8464079 DOI: 10.1093/nar/gkab754] [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: 01/18/2021] [Revised: 07/31/2021] [Accepted: 09/01/2021] [Indexed: 11/22/2022] Open
Abstract
The molecular mechanisms of aging are unsolved fundamental biological questions. Caenorhabditis elegans is an ideal model organism for investigating aging. PUF-8, a PUF (Pumilio and FBF) protein in C. elegans, is crucial for germline development through binding with the 3′ untranslated regions (3′ UTR) in the target mRNAs. Recently, PUF-8 was reported to alter mitochondrial dynamics and mitophagy by regulating MFF-1, a mitochondrial fission factor, and subsequently regulated longevity. Here, we determined the crystal structure of the PUF domain of PUF-8 with an RNA substrate. Mutagenesis experiments were performed to alter PUF-8 recognition of its target mRNAs. Those mutations reduced the fertility and extended the lifespan of C. elegans. Deep sequencing of total mRNAs from wild-type and puf-8 mutant worms as well as in vivo RNA Crosslinking and Immunoprecipitation (CLIP) experiments identified six PUF-8 regulated genes, which contain at least one PUF-binding element (PBE) at the 3′ UTR. One of the six genes, pqm-1, is crucial for lipid storage and aging process. Knockdown of pqm-1 could revert the lifespan extension of puf-8 mutant animals. We conclude that PUF-8 regulate the lifespan of C. elegans may not only via MFF but also via modulating pqm-1-related pathways.
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Affiliation(s)
- Zheng Xu
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
| | - Jie Zhao
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
| | - Minjie Hong
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
| | - Chenming Zeng
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
| | - Shouhong Guang
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
| | - Yunyu Shi
- Ministry of Education Key Laboratory for Membraneless Organelles & Cellular Dynamics, Hefei National Laboratory for Physical Sciences at the Microscale, School of Life Sciences, The First Affiliated Hospital of USTC, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, Anhui 230027, P.R. China
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57
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Luan P, D'Amico D, Andreux PA, Laurila PP, Wohlwend M, Li H, Imamura de Lima T, Place N, Rinsch C, Zanou N, Auwerx J. Urolithin A improves muscle function by inducing mitophagy in muscular dystrophy. Sci Transl Med 2021; 13:13/588/eabb0319. [PMID: 33827972 DOI: 10.1126/scitranslmed.abb0319] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 11/25/2020] [Accepted: 03/01/2021] [Indexed: 12/12/2022]
Abstract
Duchenne muscular dystrophy (DMD) is the most common muscular dystrophy, and despite advances in genetic and pharmacological disease-modifying treatments, its management remains a major challenge. Mitochondrial dysfunction contributes to DMD, yet the mechanisms by which this occurs remain elusive. Our data in experimental models and patients with DMD show that reduced expression of genes involved in mitochondrial autophagy, or mitophagy, contributes to mitochondrial dysfunction. Mitophagy markers were reduced in skeletal muscle and in muscle stem cells (MuSCs) of a mouse model of DMD. Administration of the mitophagy activator urolithin A (UA) rescued mitophagy in DMD worms and mice and in primary myoblasts from patients with DMD, increased skeletal muscle respiratory capacity, and improved MuSCs' regenerative ability, resulting in the recovery of muscle function and increased survival in DMD mouse models. These data indicate that restoration of mitophagy alleviates symptoms of DMD and suggest that UA may have potential therapeutic applications for muscular dystrophies.
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Affiliation(s)
- Peiling Luan
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Davide D'Amico
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.,Amazentis SA, Ecole Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, 1015 Lausanne, Switzerland
| | - Pénélope A Andreux
- Amazentis SA, Ecole Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, 1015 Lausanne, Switzerland
| | - Pirkka-Pekka Laurila
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Martin Wohlwend
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Hao Li
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Tanes Imamura de Lima
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland
| | - Nicolas Place
- Institute of Sport Sciences, Quartier UNIL-Centre, Faculty of Biology-Medicine, University of Lausanne, Bâtiment Synathlon, 1015 Lausanne, Switzerland
| | - Chris Rinsch
- Amazentis SA, Ecole Polytechnique Fédérale de Lausanne (EPFL) Innovation Park, 1015 Lausanne, Switzerland
| | - Nadège Zanou
- Institute of Sport Sciences, Quartier UNIL-Centre, Faculty of Biology-Medicine, University of Lausanne, Bâtiment Synathlon, 1015 Lausanne, Switzerland
| | - Johan Auwerx
- Laboratory for Integrative and Systems Physiology, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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58
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Li D, Yang S, Xing Y, Pan L, Zhao R, Zhao Y, Liu L, Wu M. Novel Insights and Current Evidence for Mechanisms of Atherosclerosis: Mitochondrial Dynamics as a Potential Therapeutic Target. Front Cell Dev Biol 2021; 9:673839. [PMID: 34307357 PMCID: PMC8293691 DOI: 10.3389/fcell.2021.673839] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 06/16/2021] [Indexed: 12/12/2022] Open
Abstract
Cardiovascular disease (CVD) is the main cause of death worldwide. Atherosclerosis is the underlying pathological basis of CVD. Mitochondrial homeostasis is maintained through the dynamic processes of fusion and fission. Mitochondria are involved in many cellular processes, such as steroid biosynthesis, calcium homeostasis, immune cell activation, redox signaling, apoptosis, and inflammation, among others. Under stress conditions, mitochondrial dynamics, mitochondrial cristae remodeling, and mitochondrial ROS (mitoROS) production increase, mitochondrial membrane potential (MMP) decreases, calcium homeostasis is imbalanced, and mitochondrial permeability transition pore open (mPTP) and release of mitochondrial DNA (mtDNA) are activated. mtDNA recognized by TLR9 can lead to NF-κB pathway activation and pro-inflammatory factor expression. At the same time, TLR9 can also activate NLRP3 inflammasomes and release interleukin, an event that eventually leads to tissue damage and inflammatory responses. In addition, mitochondrial dysfunction may amplify the activation of NLRP3 through the production of mitochondrial ROS, which together aggravate accumulating mitochondrial damage. In addition, mtDNA defects or gene mutation can lead to mitochondrial oxidative stress. Finally, obesity, diabetes, hypertension and aging are risk factors for the progression of CVD, which are closely related to mitochondrial dynamics. Mitochondrial dynamics may represent a new target in the treatment of atherosclerosis. Antioxidants, mitochondrial inhibitors, and various new therapies to correct mitochondrial dysfunction represent a few directions for future research on therapeutic intervention and amelioration of atherosclerosis.
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Affiliation(s)
- Dan Li
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Shengjie Yang
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yanwei Xing
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Limin Pan
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Ran Zhao
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Yixi Zhao
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Longtao Liu
- Xiyuan Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Min Wu
- Guang'an Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
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59
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NORAD-induced Pumilio phase separation is required for genome stability. Nature 2021; 595:303-308. [PMID: 34108682 DOI: 10.1038/s41586-021-03633-w] [Citation(s) in RCA: 106] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Accepted: 05/11/2021] [Indexed: 01/10/2023]
Abstract
Liquid-liquid phase separation is a major mechanism of subcellular compartmentalization1,2. Although the segregation of RNA into phase-separated condensates broadly affects RNA metabolism3,4, whether and how specific RNAs use phase separation to regulate interacting factors such as RNA-binding proteins (RBPs), and the phenotypic consequences of such regulatory interactions, are poorly understood. Here we show that RNA-driven phase separation is a key mechanism through which a long noncoding RNA (lncRNA) controls the activity of RBPs and maintains genomic stability in mammalian cells. The lncRNA NORAD prevents aberrant mitosis by inhibiting Pumilio (PUM) proteins5-8. We show that NORAD can out-compete thousands of other PUM-binding transcripts to inhibit PUM by nucleating the formation of phase-separated PUM condensates, termed NP bodies. Dual mechanisms of PUM recruitment, involving multivalent PUM-NORAD and PUM-PUM interactions, enable NORAD to competitively sequester a super-stoichiometric amount of PUM in NP bodies. Disruption of NORAD-driven PUM phase separation leads to PUM hyperactivity and genome instability that is rescued by synthetic RNAs that induce the formation of PUM condensates. These results reveal a mechanism by which RNA-driven phase separation can regulate RBP activity and identify an essential role for this process in genome maintenance. The repetitive sequence architecture of NORAD and other lncRNAs9-11 suggests that phase separation may be a widely used mechanism of lncRNA-mediated regulation.
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60
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Abstract
Cells use mitophagy to remove dysfunctional or excess mitochondria, frequently in response to imposed stresses, such as hypoxia and nutrient deprivation. Mitochondrial cargo receptors (MCR) induced by these stresses target mitochondria to autophagosomes through interaction with members of the LC3/GABARAP family. There are a growing number of these MCRs, including BNIP3, BNIP3L, FUNDC1, Bcl2-L-13, FKBP8, Prohibitin-2, and others, in addition to mitochondrial protein targets of PINK1/Parkin phospho-ubiquitination. There is also an emerging link between mitochondrial lipid signaling and mitophagy where ceramide, sphingosine-1-phosphate, and cardiolipin have all been shown to promote mitophagy. Here, we review the upstream signaling mechanisms that regulate mitophagy, including components of the mitochondrial fission machinery, AMPK, ATF4, FoxOs, Sirtuins, and mtDNA release, and address the significance of these pathways for stress responses in tumorigenesis and metastasis. In particular, we focus on how mitophagy modulators intersect with cell cycle control and survival pathways in cancer, including following ECM detachment and during cell migration and metastasis. Finally, we interrogate how mitophagy affects tissue atrophy during cancer cachexia and therapy responses in the clinic.
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Affiliation(s)
- Logan P Poole
- The Ben May Department for Cancer Research, The Gordon Center for Integrative Sciences, W-338, The University of Chicago, 929 E 57th Street, Chicago, IL, 60637, USA
- The Committee on Cancer Biology, The University of Chicago, Chicago, USA
| | - Kay F Macleod
- The Ben May Department for Cancer Research, The Gordon Center for Integrative Sciences, W-338, The University of Chicago, 929 E 57th Street, Chicago, IL, 60637, USA.
- The Committee on Cancer Biology, The University of Chicago, Chicago, USA.
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61
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Wrighton PJ, Shwartz A, Heo JM, Quenzer ED, LaBella KA, Harper JW, Goessling W. Quantitative intravital imaging in zebrafish reveals in vivo dynamics of physiological-stress-induced mitophagy. J Cell Sci 2021; 134:jcs.256255. [PMID: 33536245 DOI: 10.1242/jcs.256255] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 01/19/2021] [Indexed: 12/16/2022] Open
Abstract
Mitophagy, the selective recycling of mitochondria through autophagy, is a crucial metabolic process induced by cellular stress, and defects are linked to aging, sarcopenia and neurodegenerative diseases. To therapeutically target mitophagy, the fundamental in vivo dynamics and molecular mechanisms must be fully understood. Here, we generated mitophagy biosensor zebrafish lines expressing mitochondrially targeted, pH-sensitive fluorescent probes, mito-Keima and mito-EGFP-mCherry, and used quantitative intravital imaging to illuminate mitophagy during physiological stresses, namely, embryonic development, fasting and hypoxia. In fasted muscle, volumetric mitolysosome size analyses documented organelle stress response dynamics, and time-lapse imaging revealed that mitochondrial filaments undergo piecemeal fragmentation and recycling rather than the wholesale turnover observed in cultured cells. Hypoxia-inducible factor (Hif) pathway activation through physiological hypoxia or chemical or genetic modulation also provoked mitophagy. Intriguingly, mutation of a single mitophagy receptor (bnip3) prevented this effect, whereas disruption of other putative hypoxia-associated mitophagy genes [bnip3la (nix), fundc1, pink1 or prkn (Parkin)] had no effect. This in vivo imaging study establishes fundamental dynamics of fasting-induced mitophagy and identifies bnip3 as the master regulator of Hif-induced mitophagy in vertebrate muscle.
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Affiliation(s)
- Paul J Wrighton
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Arkadi Shwartz
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jin-Mi Heo
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Eleanor D Quenzer
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Kyle A LaBella
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - J Wade Harper
- Department of Cell Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Wolfram Goessling
- Division of Genetics, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA .,Harvard Stem Cell Institute, Cambridge, MA 02138, USA.,Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.,Harvard-MIT Division of Health Sciences and Technology, Boston, MA 02115, USA.,Division of Gastroenterology, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02114, USA
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62
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Chen Y, Wu YY, Si HB, Lu YR, Shen B. Mechanistic insights into AMPK-SIRT3 positive feedback loop-mediated chondrocyte mitochondrial quality control in osteoarthritis pathogenesis. Pharmacol Res 2021; 166:105497. [PMID: 33609697 DOI: 10.1016/j.phrs.2021.105497] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 02/09/2021] [Accepted: 02/14/2021] [Indexed: 02/08/2023]
Abstract
Osteoarthritis (OA) is a major cause of disability in the elderly population and represents a significant public health problem and socioeconomic burden worldwide. However, no disease-modifying therapeutics are currently available for OA due to an insufficient understanding of the pathogenesis of this disability. As a unique cell type in cartilage, chondrocytes are essential for cartilage homeostasis and play a critical role in OA pathogenesis. Mitochondria are important metabolic centers in chondrocytes and contribute to cell survival, and mitochondrial quality control (MQC) is an emerging mechanism for maintaining cell homeostasis. An increasing number of recent studies have demonstrated that dysregulation of the key processes of chondrocyte MQC, which involve mitochondrial redox, biogenesis, dynamics, and mitophagy, is associated with OA pathogenesis and can be regulated by the chondroprotective molecules 5' adenosine monophosphate-activated protein kinase (AMPK) and sirtuin 3 (SIRT3). Moreover, AMPK and SIRT3 regulate each other, and their expression and activity are always consistent in chondrocytes, which suggests the existence of an AMPK-SIRT3 positive feedback loop (PFL). Although the precise mechanisms are not fully elucidated and need further validation, the current literature indicates that this AMPK-SIRT3 PFL regulates OA development and progression, at least partially by mediating chondrocyte MQC. Therefore, understanding the mechanisms of AMPK-SIRT3 PFL-mediated chondrocyte MQC in OA pathogenesis might yield new ideas and potential targets for subsequent research on the OA pathomechanism and therapeutics.
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Affiliation(s)
- Yang Chen
- Department of Orthopaedics, Key Laboratory of Transplant Engineering and Immunology, Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Yong-Yao Wu
- West China College of Stomatology, Sichuan University, Chengdu 610041, China
| | - Hai-Bo Si
- Department of Orthopaedics, Key Laboratory of Transplant Engineering and Immunology, Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China.
| | - Yan-Rong Lu
- Department of Orthopaedics, Key Laboratory of Transplant Engineering and Immunology, Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
| | - Bin Shen
- Department of Orthopaedics, Key Laboratory of Transplant Engineering and Immunology, Regenerative Medicine Research Center, West China Hospital, Sichuan University, Chengdu 610041, China
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63
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Zhang S, Chen Y, Wang Y, Zhang P, Chen G, Zhou Y. Insights Into Translatomics in the Nervous System. Front Genet 2021; 11:599548. [PMID: 33408739 PMCID: PMC7779767 DOI: 10.3389/fgene.2020.599548] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 11/30/2020] [Indexed: 12/11/2022] Open
Abstract
Most neurological disorders are caused by abnormal gene translation. Generally, dysregulation of elements involved in the translational process disrupts homeostasis in neurons and neuroglia. Better understanding of how the gene translation process occurs requires detailed analysis of transcriptomic and proteomic profile data. However, a lack of strictly direct correlations between mRNA and protein levels limits translational investigation by combining transcriptomic and proteomic profiling. The much better correlation between proteins and translated mRNAs than total mRNAs in abundance and insufficiently sensitive proteomics approach promote the requirement of advances in translatomics technology. Translatomics which capture and sequence the mRNAs associated with ribosomes has been effective in identifying translational changes by genetics or projections, ribosome stalling, local translation, and transcript isoforms in the nervous system. Here, we place emphasis on the main three translatomics methods currently used to profile mRNAs attached to ribosome-nascent chain complex (RNC-mRNA). Their prominent applications in neurological diseases including glioma, neuropathic pain, depression, fragile X syndrome (FXS), neurodegenerative disorders are outlined. The content reviewed here expands our understanding on the contributions of aberrant translation to neurological disease development.
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Affiliation(s)
- Shuxia Zhang
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yeru Chen
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yongjie Wang
- Key Laboratory of Elemene Anti-Cancer Medicine of Zhejiang Province and Holistic Integrative Pharmacy Institutes, Hangzhou Normal University, Hangzhou, China.,Engineering Laboratory of Development and Application of Traditional Chinese Medicine from Zhejiang Province, Holistic Integrative Pharmacy Institutes, Hangzhou Normal University, Hangzhou, China
| | - Piao Zhang
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Gang Chen
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Youfa Zhou
- Department of Anesthesiology, Sir Run Run Shaw Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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64
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Tran M, Reddy PH. Defective Autophagy and Mitophagy in Aging and Alzheimer's Disease. Front Neurosci 2021; 14:612757. [PMID: 33488352 PMCID: PMC7820371 DOI: 10.3389/fnins.2020.612757] [Citation(s) in RCA: 77] [Impact Index Per Article: 25.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 11/17/2020] [Indexed: 12/12/2022] Open
Abstract
Aging is the time-dependent process that all living organisms go through characterized by declining physiological function due to alterations in metabolic and molecular pathways. Many decades of research have been devoted to uncovering the cellular changes and progression of aging and have revealed that not all organisms with the same chronological age exhibit the same age-related declines in physiological function. In assessing biological age, factors such as epigenetic changes, telomere length, oxidative damage, and mitochondrial dysfunction in rescue mechanisms such as autophagy all play major roles. Recent studies have focused on autophagy dysfunction in aging, particularly on mitophagy due to its major role in energy generation and reactive oxidative species generation of mitochondria. Mitophagy has been implicated in playing a role in the pathogenesis of many age-related diseases, including Alzheimer's disease (AD), Parkinson's, Huntington's, and amyotrophic lateral sclerosis. The purpose of our article is to highlight the mechanisms of autophagy and mitophagy and how defects in these pathways contribute to the physiological markers of aging and AD. This article also discusses how mitochondrial dysfunction, abnormal mitochondrial dynamics, impaired biogenesis, and defective mitophagy are related to aging and AD progression. This article highlights recent studies of amyloid beta and phosphorylated tau in relation to autophagy and mitophagy in AD.
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Affiliation(s)
- Michael Tran
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
| | - P. Hemachandra Reddy
- Department of Internal Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Neuroscience and Pharmacology, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Neurology, Departments of School of Medicine, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Public Health Department of Graduate School of Biomedical Sciences, Texas Tech University Health Sciences Center, Lubbock, TX, United States
- Department of Speech, Language and Hearing Sciences, School Health Professions, Texas Tech University Health Sciences Center, Lubbock, TX, United States
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65
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Romani M, Sorrentino V, Oh CM, Li H, de Lima TI, Zhang H, Shong M, Auwerx J. NAD + boosting reduces age-associated amyloidosis and restores mitochondrial homeostasis in muscle. Cell Rep 2021; 34:108660. [PMID: 33472069 PMCID: PMC7816122 DOI: 10.1016/j.celrep.2020.108660] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 09/17/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
Aging is characterized by loss of proteostasis and mitochondrial homeostasis. Here, we provide bioinformatic evidence of dysregulation of mitochondrial and proteostasis pathways in muscle aging and diseases. Moreover, we show accumulation of amyloid-like deposits and mitochondrial dysfunction during natural aging in the body wall muscle of C. elegans, in human primary myotubes, and in mouse skeletal muscle, partially phenocopying inclusion body myositis (IBM). Importantly, NAD+ homeostasis is critical to control age-associated muscle amyloidosis. Treatment of either aged N2 worms, a nematode model of amyloid-beta muscle proteotoxicity, human aged myotubes, or old mice with the NAD+ boosters nicotinamide riboside (NR) and olaparib (AZD) increases mitochondrial function and muscle homeostasis while attenuating amyloid accumulation. Hence, our data reveal that age-related amyloidosis is a contributing factor to mitochondrial dysfunction and that both are features of the aging muscle that can be ameliorated by NAD+ metabolism-enhancing approaches, warranting further clinical studies. Amyloidosis and mitochondrial dysfunction typify muscle aging and disease across species NAD+ homeostasis is required to maintain proteostasis in nematodes and mammalian cells Reducing age-associated amyloidosis improves healthspan and mitochondrial function Late-life NAD+ boosting reduces amyloidosis and mitochondrial dysfunction during aging
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Affiliation(s)
- Mario Romani
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Vincenzo Sorrentino
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Chang-Myung Oh
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland; Department of Endocrinology and Metabolism, CHA Bundang Medical Center, School of Medicine CHA University, Seongnam 13497, South Korea; Department of Biomedical Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 61005, South Korea
| | - Hao Li
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Tanes Imamura de Lima
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Hongbo Zhang
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland
| | - Minho Shong
- Research Center for Endocrine and Metabolic Diseases, Chungnam National University School of Medicine, Daejeon 35015, South Korea
| | - Johan Auwerx
- Laboratory of Integrative Systems Physiology, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
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66
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Skeletal muscle RBM3 expression is associated with extended lifespan in Ames Dwarf and calorie restricted mice. Exp Gerontol 2020; 146:111214. [PMID: 33385482 DOI: 10.1016/j.exger.2020.111214] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/23/2020] [Accepted: 12/15/2020] [Indexed: 11/24/2022]
Abstract
RNA binding protein motif 3 (RBM3) is an RNA-binding and cold shock protein that protects myoblasts and promotes skeletal muscle hypertrophy by enhancing mRNA stability and translation. Muscle size is decreased during aging; however, it is typically delayed in models of extended lifespan such as the long-lived Ames Dwarf (df/df) mice and calorie restricted (CR) animals compared to age-matched controls. In light of the protective and anabolic effects of RBM3 in muscle, we hypothesized that RBM3 expression is higher in long-lived animal models. Young and old df/df mice, and adult and old UM-HET3 CR mice were used to test this hypothesis. Gastrocnemius muscles were harvested and protein was isolated for RBM3 protein measurements. CR induced a 1.7 and 1.3-fold elevation in RBM3 protein abundance compared to adult and old male mice fed ad libitum (AL) diets, respectively; this effect was shared between males and females. Ames dwarfism induced a 4.6 and 2.7-fold elevation in RBM3 protein abundance in young and old df/df mice compared to normal control littermates, respectively. In contrast, there was an age-associated decrease in cold-inducible RNA-binding protein (CIRP), suggesting these effects are specific for RBM3. Lastly, there was an age-associated increase in RNA degradation marker decapping enzyme 2 (DCP2) in UM-HET3 mice that was mitigated by CR. These results show that muscle RBM3 expression is correlated with extended lifespan in both df/df and CR animals. Identifying how RBM3 exerts protective effects in muscle may yield new insights into healthy aging of skeletal muscle.
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67
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The Interplay between Mitochondrial Morphology and Myomitokines in Aging Sarcopenia. Int J Mol Sci 2020; 22:ijms22010091. [PMID: 33374852 PMCID: PMC7796142 DOI: 10.3390/ijms22010091] [Citation(s) in RCA: 43] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 12/13/2022] Open
Abstract
Sarcopenia is a chronic disease characterized by the progressive loss of skeletal muscle mass, force, and function during aging. It is an emerging public problem associated with poor quality of life, disability, frailty, and high mortality. A decline in mitochondria quality control pathways constitutes a major mechanism driving aging sarcopenia, causing abnormal organelle accumulation over a lifetime. The resulting mitochondrial dysfunction in sarcopenic muscles feedbacks systemically by releasing the myomitokines fibroblast growth factor 21 (FGF21) and growth and differentiation factor 15 (GDF15), influencing the whole-body homeostasis and dictating healthy or unhealthy aging. This review describes the principal pathways controlling mitochondrial quality, many of which are potential therapeutic targets against muscle aging, and the connection between mitochondrial dysfunction and the myomitokines FGF21 and GDF15 in the pathogenesis of aging sarcopenia.
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68
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Asplund O, Rung J, Groop L, Prasad B R, Hansson O. MuscleAtlasExplorer: a web service for studying gene expression in human skeletal muscle. Database (Oxford) 2020; 2020:baaa111. [PMID: 33338203 PMCID: PMC7747357 DOI: 10.1093/database/baaa111] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Revised: 10/13/2020] [Accepted: 12/14/2020] [Indexed: 01/30/2023]
Abstract
MuscleAtlasExplorer is a freely available web application that allows for the exploration of gene expression data from human skeletal muscle. It draws from an extensive publicly available dataset of 1654 skeletal muscle expression microarray samples. Detailed, manually curated, patient phenotype data, with information such as age, sex, BMI and disease status, are combined with skeletal muscle gene expression to provide insights into gene function in skeletal muscle. It aims to facilitate easy exploration of the data using powerful data visualization functions, while allowing for sample selection, in-depth inspection and further analysis using external tools. Availability: MuscleAtlasExplorer is available at https://mae.crc.med.lu.se/mae2 (username 'muscle' and password 'explorer' pre-publication).
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Affiliation(s)
- Olof Asplund
- Genomics, Diabetes and Endocrinology Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Jan Waldenströms gata 35, Malmö 20502, Sweden
| | - Johan Rung
- SciLifeLab, BMC, Husargatan 3, Uppsala University, Uppsala 751 22, Sweden
| | - Leif Groop
- Genomics, Diabetes and Endocrinology Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Jan Waldenströms gata 35, Malmö 20502, Sweden
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Tukholmankatu 800290 Helsinki, Finland
| | - Rashmi Prasad B
- Genomics, Diabetes and Endocrinology Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Jan Waldenströms gata 35, Malmö 20502, Sweden
| | - Ola Hansson
- Genomics, Diabetes and Endocrinology Unit, Department of Clinical Sciences, Lund University Diabetes Centre, Jan Waldenströms gata 35, Malmö 20502, Sweden
- Institute for Molecular Medicine Finland (FIMM), University of Helsinki, Tukholmankatu 800290 Helsinki, Finland
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69
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Romanello V, Sandri M. The connection between the dynamic remodeling of the mitochondrial network and the regulation of muscle mass. Cell Mol Life Sci 2020; 78:1305-1328. [PMID: 33078210 PMCID: PMC7904552 DOI: 10.1007/s00018-020-03662-0] [Citation(s) in RCA: 100] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 09/02/2020] [Accepted: 09/28/2020] [Indexed: 12/11/2022]
Abstract
The dynamic coordination of processes controlling the quality of the mitochondrial network is crucial to maintain the function of mitochondria in skeletal muscle. Changes of mitochondrial proteolytic system, dynamics (fusion/fission), and mitophagy induce pathways that affect muscle mass and performance. When muscle mass is lost, the risk of disease onset and premature death is dramatically increased. For instance, poor quality of muscles correlates with the onset progression of several age-related disorders such as diabetes, obesity, cancer, and aging sarcopenia. To date, there are no drug therapies to reverse muscle loss, and exercise remains the best approach to improve mitochondrial health and to slow atrophy in several diseases. This review will describe the principal mechanisms that control mitochondrial quality and the pathways that link mitochondrial dysfunction to muscle mass regulation.
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Affiliation(s)
- Vanina Romanello
- Venetian Institute of Molecular Medicine, via Orus 2, 35129, Padova, Italy.
- Department of Biomedical Science, University of Padova, via G. Colombo 3, 35100, Padova, Italy.
| | - Marco Sandri
- Venetian Institute of Molecular Medicine, via Orus 2, 35129, Padova, Italy.
- Department of Biomedical Science, University of Padova, via G. Colombo 3, 35100, Padova, Italy.
- Department of Medicine, McGill University, Montreal, Canada.
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70
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Ren L, Chen X, Chen X, Li J, Cheng B, Xia J. Mitochondrial Dynamics: Fission and Fusion in Fate Determination of Mesenchymal Stem Cells. Front Cell Dev Biol 2020; 8:580070. [PMID: 33178694 PMCID: PMC7593605 DOI: 10.3389/fcell.2020.580070] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Accepted: 09/24/2020] [Indexed: 12/14/2022] Open
Abstract
Mesenchymal stem cells (MSCs) are pivotal to tissue homeostasis, repair, and regeneration due to their potential for self-renewal, multilineage differentiation, and immune modulation. Mitochondria are highly dynamic organelles that maintain their morphology via continuous fission and fusion, also known as mitochondrial dynamics. MSCs undergo specific mitochondrial dynamics during proliferation, migration, differentiation, apoptosis, or aging. Emerging evidence suggests that mitochondrial dynamics are key contributors to stem cell fate determination. The coordination of mitochondrial fission and fusion is crucial for cellular function and stress responses, while abnormal fission and/or fusion causes MSC dysfunction. This review focuses on the role of mitochondrial dynamics in MSC commitment under physiological and stress conditions. We highlight mechanistic insights into modulating mitochondrial dynamics and mitochondrial strategies for stem cell-based regenerative medicine. These findings shed light on the contribution of mitochondrial dynamics to MSC fate and MSC-based tissue repair.
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Affiliation(s)
- Lin Ren
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Xiaodan Chen
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Xiaobing Chen
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Jiayan Li
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Bin Cheng
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
| | - Juan Xia
- Hospital of Stomatology, Sun Yat-sen University, Guangzhou, China.,Guangdong Provincial Key Laboratory of Stomatology, Guangzhou, China.,Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou, China
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71
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Webb M, Sideris DP. Intimate Relations-Mitochondria and Ageing. Int J Mol Sci 2020; 21:ijms21207580. [PMID: 33066461 PMCID: PMC7589147 DOI: 10.3390/ijms21207580] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Revised: 10/05/2020] [Accepted: 10/06/2020] [Indexed: 12/14/2022] Open
Abstract
Mitochondrial dysfunction is associated with ageing, but the detailed causal relationship between the two is still unclear. We review the major phenomenological manifestations of mitochondrial age-related dysfunction including biochemical, regulatory and energetic features. We conclude that the complexity of these processes and their inter-relationships are still not fully understood and at this point it seems unlikely that a single linear cause and effect relationship between any specific aspect of mitochondrial biology and ageing can be established in either direction.
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Affiliation(s)
- Michael Webb
- Mitobridge Inc., an Astellas Company, 1030 Massachusetts Ave, Cambridge, MA 02138, USA
| | - Dionisia P Sideris
- Mitobridge Inc., an Astellas Company, 1030 Massachusetts Ave, Cambridge, MA 02138, USA
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72
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Ajoolabady A, Aslkhodapasandhokmabad H, Aghanejad A, Zhang Y, Ren J. Mitophagy Receptors and Mediators: Therapeutic Targets in the Management of Cardiovascular Ageing. Ageing Res Rev 2020; 62:101129. [PMID: 32711157 DOI: 10.1016/j.arr.2020.101129] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 07/10/2020] [Accepted: 07/19/2020] [Indexed: 12/17/2022]
Abstract
Mitophagy serves as a cardinal regulator in the maintenance of mitochondrial integrity, function, and cardiovascular homeostasis, through the fine control and governance of cellular metabolism, ATP production, redox balance, and mitochondrial quality and quantity control. As a unique form of selective autophagy, mitophagy specifically recognizes and engulfs long-lived or damaged (depolarized) mitochondria through formation of the double-membraned intracellular organelles - mitophagosomes, ultimately resulting in lysosomal degradation. Levels of mitophagy are reported to be altered in pathological settings including cardiovascular diseases and biological ageing although the precise nature of mitophagy change in ageing and ageing-associated cardiovascular deterioration remains poorly defined. Ample clinical and experimental evidence has depicted a convincing tie between cardiovascular ageing and altered mitophagy. In particular, ageing perturbs multiple enigmatic various signal machineries governing mitophagy, mitochondrial quality, and mitochondrial function, contributing to ageing-elicited anomalies in the cardiovascular system. This review will update novel regulatory mechanisms of mitophagy especially in the perspective of advanced ageing, and discuss how mitophagy dysregulation may be linked to cardiovascular abnormalities in ageing. We hope to pave the way for development of new therapeutic strategies against the growing health and socieconomical issue of cardiovascular ageing through targeting mitophagy.
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73
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Wang J, Zhu P, Toan S, Li R, Ren J, Zhou H. Pum2-Mff axis fine-tunes mitochondrial quality control in acute ischemic kidney injury. Cell Biol Toxicol 2020; 36:365-378. [PMID: 31993882 DOI: 10.1007/s10565-020-09513-9] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Accepted: 01/24/2020] [Indexed: 12/31/2022]
Abstract
Mitochondrial fission factor (Mff) has been demonstrated to play a role in the activation of mitochondrial cleavage and mitochondrial death, denoting its role in the regulation of mitochondrial quality control. Recent evidence suggested that the mRNA translation of Mff is under the negative regulation by the RNA-binding protein Pumilio2 (Pum2). This study was designed to examine the role of Pum2 and Mff in the governance of mitochondrial quality control in a murine model of acute ischemic kidney injury. Our results indicated that genetic deletion of Mff overtly attenuated ischemic acute kidney injury (AKI)-induced renal failure through inhibition of pro-inflammatory response, tubular oxidative stress, and ultimately cell death in the kidney. Furthermore, Mff inhibition effectively preserved mitochondrial homeostasis through amelioration of mitochondrial mitosis, restoration of Sirt1/3 expression, and boost of mitochondrial respiration. Western blot analysis revealed that levels of Pum2 were significantly downregulated by ischemic AKI, inversely coinciding with levels of Mff. Overexpression of Pum2 reduced ischemic AKI-mediated Mff upregulation and offered protection on renal tubules through modulation of mitochondrial quality control. Taken together, our data have unveiled the molecular mechanism of the Pum2-Mff axis in mitochondrial quality control in a mouse model of ischemic AKI. These data indicated the therapeutic potential of Pum2 activation and Mff inhibition in the management of ischemic AKI.
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Affiliation(s)
- Jin Wang
- Medical School of Chinese PLA, Chinese PLA General Hospital, Beijing, China
| | - Pingjun Zhu
- Medical School of Chinese PLA, Chinese PLA General Hospital, Beijing, China
| | - Sam Toan
- Department of Chemical Engineering, University of Minnesota-Duluth, Duluth, MN, 55812, USA
| | - Ruibing Li
- Medical School of Chinese PLA, Chinese PLA General Hospital, Beijing, China
| | - Jun Ren
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, Laramie, WY, 82071, USA.
| | - Hao Zhou
- Medical School of Chinese PLA, Chinese PLA General Hospital, Beijing, China.
- Center for Cardiovascular Research and Alternative Medicine, University of Wyoming, Laramie, WY, 82071, USA.
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74
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Leboutet R, Chen Y, Legouis R, Culetto E. Mitophagy during development and stress in C. elegans. Mech Ageing Dev 2020; 189:111266. [DOI: 10.1016/j.mad.2020.111266] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 05/19/2020] [Accepted: 05/20/2020] [Indexed: 12/13/2022]
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75
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Song P, Zhao Q, Zou MH. Targeting senescent cells to attenuate cardiovascular disease progression. Ageing Res Rev 2020; 60:101072. [PMID: 32298812 DOI: 10.1016/j.arr.2020.101072] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 04/07/2020] [Accepted: 04/09/2020] [Indexed: 12/19/2022]
Abstract
Cardiovascular disease (CVD) is the most common disease to increase as life expectancy increases. Most high-profile pharmacological treatments for age-related CVD have led to inefficacious results, implying that novel approaches to treating these pathologies are needed. Emerging data have demonstrated that senescent cardiovascular cells, which are characterized by irreversible cell cycle arrest and a distinct senescence-associated secretory phenotype, accumulate in aged or diseased cardiovascular systems, suggesting that they may impair cardiovascular function. This review discusses the evidence implicating senescent cells in cardiovascular ageing, the onset and progression of CVD, and the molecular mechanisms underlying cardiovascular cell senescence. We also review eradication of senescent cardiovascular cells by small-molecule-drug-mediated apoptosis and immune cell-mediated efferocytosis and toxicity as promising and precisely targeted therapeutics for CVD prevention and treatment.
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76
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Ravanidis S, Doxakis E. RNA-Binding Proteins Implicated in Mitochondrial Damage and Mitophagy. Front Cell Dev Biol 2020; 8:372. [PMID: 32582692 PMCID: PMC7287033 DOI: 10.3389/fcell.2020.00372] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 04/27/2020] [Indexed: 01/19/2023] Open
Abstract
The mitochondrial lifecycle comprises biogenesis, fusion and cristae remodeling, fission, and breakdown by the autophagosome. This cycle is essential for maintaining proper cellular function, and inhibition of any of these processes results in deterioration of bioenergetics and swift induction of apoptosis, particularly in energy-craving cells such as myocytes and neurons. Regulation of gene expression is a fundamental step in maintaining mitochondrial plasticity, mediated by (1) transcription factors that control the expression of mitochondrial mRNAs and (2) RNA-binding proteins (RBPs) that regulate mRNA splicing, stability, targeting to mitochondria, and translation. More recently, RBPs have been also shown to interact with proteins modulating the mitochondrial lifecycle. Importantly, misexpression or mutations in RBPs give rise to mitochondrial dysfunctions, and there is strong evidence to support that these mitochondrial impairments occur early in disease development, constituting leading causes of pathogenesis. This review presents key aspects of the molecular network of the disease-relevant RBPs, including transactive response DNA-binding protein 43 (TDP43), fused in sarcoma (FUS), T-cell intracellular antigen 1 (TIA1), TIA-related protein (TIAR), and pumilio (PUM) that drive mitochondrial dysfunction in the nervous system.
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Affiliation(s)
- Stylianos Ravanidis
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
| | - Epaminondas Doxakis
- Center of Basic Research, Biomedical Research Foundation, Academy of Athens, Athens, Greece
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77
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Molenaars M, Daniels EG, Meurs A, Janssens GE, Houtkooper RH. Mitochondrial cross-compartmental signalling to maintain proteostasis and longevity. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190414. [PMID: 32362258 DOI: 10.1098/rstb.2019.0414] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Lifespan in eukaryotic species can be prolonged by shifting from cellular states favouring growth to those favouring maintenance and stress resistance. For instance, perturbations in mitochondrial oxidative phosphorylation (OXPHOS) can shift cells into this latter state and extend lifespan. Because mitochondria rely on proteins synthesized from nuclear as well as mitochondrial DNA, they need to constantly send and receive messages from other compartments of the cell in order to function properly and maintain homeostasis, and lifespan extension is often dependent on this cross-compartmental signalling. Here, we describe the mechanisms of bi-directional mitochondrial cross-compartmental signalling resulting in proteostasis and longevity. These proteostasis mechanisms are highly context-dependent, governed by the origin and extent of stress. Furthermore, we discuss the translatability of these mechanisms and explore therapeutic developments, such as the antibiotic studies targeting mitochondria or mitochondria-derived peptides as therapies for age-related diseases such as neurodegeneration and cancer. This article is part of the theme issue 'Retrograde signalling from endosymbiotic organelles'.
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Affiliation(s)
- Marte Molenaars
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Eileen G Daniels
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Amber Meurs
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Georges E Janssens
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Riekelt H Houtkooper
- Laboratory Genetic Metabolic Diseases, Amsterdam UMC, University of Amsterdam, Amsterdam Gastroenterology and Metabolism, Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
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Yang GQ, Huang JC, Yuan JJ, Zhang Q, Gong CX, Chen Q, Xie Q, Xie LX, Chen R, Qiu ZM, Zhou K, Xu R, Jiang GH, Xiong XY, Yang QW. Prdx1 Reduces Intracerebral Hemorrhage-Induced Brain Injury via Targeting Inflammation- and Apoptosis-Related mRNA Stability. Front Neurosci 2020; 14:181. [PMID: 32210752 PMCID: PMC7076121 DOI: 10.3389/fnins.2020.00181] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Accepted: 02/19/2020] [Indexed: 12/19/2022] Open
Abstract
RNA-binding proteins (RBPs) have been shown to be involved in posttranscriptional regulation, which plays an important role in the pathophysiology of intracerebral hemorrhage (ICH). Peroxiredoxin 1 (Prdx1), an RBP, plays an important role in regulating inflammation and apoptosis. On the basis that inflammation and apoptosis may contribute to ICH-induced brain injury, in this study, we used ICH models coupled with in vitro experiments, to investigate the role and mechanism of Prdx1 in regulating inflammation and apoptosis by acting as an RBP after ICH. We first found that Prdx1 was significantly up-regulated in response to ICH-induced brain injury and was mainly expressed in astrocytes and microglia in ICH rat brains. After overexpressing Prdx1 by injecting adeno-associated virus (AAV) into the striatum of rats at 3 weeks, we constructed ICH models and found that Prdx1 overexpression markedly reduced inflammation and apoptosis after ICH. Furthermore, RNA immunoprecipitation combined with high-throughput sequencing (RIP-seq) in vitro revealed that Prdx1 affects the stability of inflammation- and apoptosis-related mRNA, resulting in the inhibition of inflammation and apoptosis. Finally, overexpression of Prdx1 significantly alleviated the symptoms and mortality of rats subjected to ICH. Our results show that Prdx1 reduces ICH-induced brain injury by targeting inflammation- and apoptosis-related mRNA stability. Prdx1 may be an improved therapeutic target for alleviating the brain injury caused by ICH.
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Affiliation(s)
- Guo-Qiang Yang
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Jia-Cheng Huang
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Jun-Jie Yuan
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Qin Zhang
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Chang-Xiong Gong
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Qiong Chen
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Qi Xie
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Le-Xing Xie
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Ru Chen
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Zhong-Ming Qiu
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Kai Zhou
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Rui Xu
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Guo-Hui Jiang
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Xiao-Yi Xiong
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
| | - Qing-Wu Yang
- Department of Neurology, Xinqiao Hospital, Army Medical University, Chongqing, China
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79
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Kang L, Liu S, Li J, Tian Y, Xue Y, Liu X. The mitochondria-targeted anti-oxidant MitoQ protects against intervertebral disc degeneration by ameliorating mitochondrial dysfunction and redox imbalance. Cell Prolif 2020; 53:e12779. [PMID: 32020711 PMCID: PMC7106957 DOI: 10.1111/cpr.12779] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 01/03/2020] [Accepted: 01/20/2020] [Indexed: 12/17/2022] Open
Abstract
Objective Mitochondrial dysfunction, oxidative stress and nucleus pulposus (NP) cell apoptosis are important contributors to the development and pathogenesis of intervertebral disc degeneration (IDD). Here, we comprehensively evaluated the effects of mitochondrial dynamics, mitophagic flux and Nrf2 signalling on the mitochondrial quality control, ROS production and NP cell survival in in vitro and ex vivo compression models of IDD and explored the effects of the mitochondria‐targeted anti‐oxidant MitoQ and its mechanism. Material and methods Human NP cells were exposed to mechanical compression to mimic pathological conditions. Results Compression promoted oxidative stress, mitochondrial dysfunction and NP cell apoptosis. Mechanistically, compression disrupted the mitochondrial fission/fusion balance, inducing fatal fission. Concomitantly, PINK1/Parkin‐mediated mitophagy was activated, whereas mitophagic flux was blocked. Nrf2 anti‐oxidant pathway was insufficiently activated. These caused the damaged mitochondria accumulation and persistent oxidative damage. Moreover, MitoQ restored the mitochondrial dynamics balance, alleviated the impairment of mitophagosome‐lysosome fusion and lysosomal function and enhanced the Nrf2 activity. Consequently, damaged mitochondria were eliminated, redox balance was improved, and cell survival increased. Additionally, MitoQ alleviated IDD in an ex vivo rat compression model. Conclusions These findings suggest that comodulation of mitochondrial dynamics, mitophagic flux and Nrf2 signalling alleviates sustained mitochondrial dysfunction and oxidative stress and represents a promising therapeutic strategy for IDD; furthermore, our results provide evidence that MitoQ might serve as an effective therapeutic agent for this disorder.
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Affiliation(s)
- Liang Kang
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Spine and Spinal Cord Injury, Tianjin, China
| | - Shiwei Liu
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Spine and Spinal Cord Injury, Tianjin, China
| | - Jingchao Li
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Spine and Spinal Cord Injury, Tianjin, China.,Department of Orthopedics, Tianjin Jinghai District Hospital, Tianjin, China
| | - Yueyang Tian
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Spine and Spinal Cord Injury, Tianjin, China
| | - Yuan Xue
- Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, China.,Tianjin Key Laboratory of Spine and Spinal Cord Injury, Tianjin, China
| | - Xiaozhi Liu
- Central Laboratory, The Fifth Central Hospital of Tianjin, Tianjin, China
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80
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Si L, Fu J, Liu W, Hayashi T, Mizuno K, Hattori S, Fujisaki H, Onodera S, Ikejima T. Silibinin-induced mitochondria fission leads to mitophagy, which attenuates silibinin-induced apoptosis in MCF-7 and MDA-MB-231 cells. Arch Biochem Biophys 2020; 685:108284. [PMID: 32014401 DOI: 10.1016/j.abb.2020.108284] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Revised: 01/19/2020] [Accepted: 01/27/2020] [Indexed: 02/08/2023]
Abstract
We reported previously that higher doses (150-250 μM) of silibinin enhanced fission and inhibited fusion of mitochondria, accompanying apoptosis of double-positive breast cancer cell line MCF-7 cells and triple-negative breast cancer cell line MDA-MB-231 cells. We report here three important questions yet unclarified in the previous study; 1) Whether enhanced fission of mitochondria by the treatment of silibinin leads to mitophagy, 2) Whether mitophagy positively contributes to apoptosis and 3) Whether estrogen receptor-positive (ER+) MCF-7 cells and estrogen receptor-negative (ER-) MDA-MB-231 cells are affected in a different way by silibinin treatment, since silibinin often works through ERs signaling pathway. Mitophagy driven by Pink1/Parkin signaling, plays an important role in eliminating damaged mitochondria. Indeed, increased expression of Pink1 and the recruitment of Parkin and LC3-II to mitochondria by the treatment with silibinin account for silibinin induction of mitophagy. In this study, the effects of mitochondrial division inhibitor 1 (mdivi-1) and small interfering RNA targeting dynamin-related protein 1 (DRP1) were examined to reveal the effect of mitochondrial fission on mitophagy. As expected, mdivi-1 or siRNA targeting DRP1 reversed silibinin-induced mitochondrial fission due to down-regulation in the expression of DRP1. Inhibition of mitochondrial fission by mdivi-1 prevented induction of mitophagy as well as autophagy in both MCF-7 and MDA-MB-231 cells, indicating that silibinin-induced mitochondrial fission leads to mitophagy. Inhibition of mitochondrial fission efficiently prevented silibinin-induced apoptosis in MCF-7 and MDA-MB-231 cells in our previous work, and the second point of the present study, inhibition of mitophagy by Pink1 or Parkin knockdown increased silibinin-induced apoptosis of these cells, respectively, suggesting that the mitophagy induced by silibinin treatment serves as a cytoprotective effect, resulting in reduction of apoptosis of cancer cells in both cells. In the third point, we studied whether estrogen receptors (ERs) played a role in silibinin-induced mitophagy and apoptosis in MCF-7 and MDA-MB-231 cells. ERα and ERβ are not involved in silibinin-induced mitophagic process in MCF-7 and MDA-MB-231 cells. These findings demonstrated that silibinin induced mitochondria fission leads to mitophagy, which attenuates silibinin-induced apoptosis not through ERs-Pink1 or -Parkin pathway in MCF-7 and MDA-MB-231.
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Affiliation(s)
- Lingling Si
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China
| | - Jianing Fu
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China
| | - Weiwei Liu
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China
| | - Toshihiko Hayashi
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China; Department of Chemistry and Life Science, School of Advanced Engineering, Kogakuin University, 2665-1, Nakanomachi, Hachioji, Tokyo, 192-0015, Japan
| | - Kazunori Mizuno
- Nippi Research Institute of Biomatrix, Toride, Ibaraki, 302-0017, Japan
| | - Shunji Hattori
- Nippi Research Institute of Biomatrix, Toride, Ibaraki, 302-0017, Japan
| | - Hitomi Fujisaki
- Nippi Research Institute of Biomatrix, Toride, Ibaraki, 302-0017, Japan
| | - Satoshi Onodera
- Medical Research Institute of Curing Mibyo, 1-6-28 Narusedai Machida Tokyo, 194-0042, Japan
| | - Takashi Ikejima
- Wuya College of Innovation, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China; Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug Research & Development, Shenyang Pharmaceutical University, Shenyang, 110016, Liaoning, PR China.
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81
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Sharma A, Smith HJ, Yao P, Mair WB. Causal roles of mitochondrial dynamics in longevity and healthy aging. EMBO Rep 2019; 20:e48395. [PMID: 31667999 PMCID: PMC6893295 DOI: 10.15252/embr.201948395] [Citation(s) in RCA: 96] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 07/24/2019] [Accepted: 10/09/2019] [Indexed: 12/14/2022] Open
Abstract
Mitochondria are organized in the cell in the form of a dynamic, interconnected network. Mitochondrial dynamics, regulated by mitochondrial fission, fusion, and trafficking, ensure restructuring of this complex reticulum in response to nutrient availability, molecular signals, and cellular stress. Aberrant mitochondrial structures have long been observed in aging and age-related diseases indicating that mitochondrial dynamics are compromised as cells age. However, the specific mechanisms by which aging affects mitochondrial dynamics and whether these changes are causally or casually associated with cellular and organismal aging is not clear. Here, we review recent studies that show specifically how mitochondrial fission, fusion, and trafficking are altered with age. We discuss factors that change with age to directly or indirectly influence mitochondrial dynamics while examining causal roles for altered mitochondrial dynamics in healthy aging and underlying functional outputs that might affect longevity. Lastly, we propose that altered mitochondrial dynamics might not just be a passive consequence of aging but might constitute an adaptive mechanism to mitigate age-dependent cellular impairments and might be targeted to increase longevity and promote healthy aging.
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Affiliation(s)
- Arpit Sharma
- Department of Genetics and Complex DiseasesHarvard T.H. Chan School of Public HealthBostonMAUSA
| | - Hannah J Smith
- Department of Genetics and Complex DiseasesHarvard T.H. Chan School of Public HealthBostonMAUSA
| | - Pallas Yao
- Department of Genetics and Complex DiseasesHarvard T.H. Chan School of Public HealthBostonMAUSA
| | - William B Mair
- Department of Genetics and Complex DiseasesHarvard T.H. Chan School of Public HealthBostonMAUSA
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82
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Liu P, Li D, Li W, Wang D. Mitochondrial Unfolded Protein Response to Microgravity Stress in Nematode Caenorhabditis elegans. Sci Rep 2019; 9:16474. [PMID: 31712608 PMCID: PMC6848112 DOI: 10.1038/s41598-019-53004-9] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Accepted: 10/24/2019] [Indexed: 11/29/2022] Open
Abstract
Caenorhabditis elegans is useful for assessing biological effects of spaceflight and simulated microgravity. The molecular response of organisms to simulated microgravity is still largely unclear. Mitochondrial unfolded protein response (mt UPR) mediates a protective response against toxicity from environmental exposure in nematodes. Using HSP-6 and HSP-60 as markers of mt UPR, we observed a significant activation of mt UPR in simulated microgravity exposed nematodes. The increase in HSP-6 and HSP-60 expression mediated a protective response against toxicity of simulated microgravity. In simulated microgravity treated nematodes, mitochondria-localized ATP-binding cassette protein HAF-1 and homeodomain-containing transcriptional factor DVE-1 regulated the mt UPR activation. In the intestine, a signaling cascade of HAF-1/DVE-1-HSP-6/60 was required for control of toxicity of simulated microgravity. Therefore, our data suggested the important role of mt UPR activation against the toxicity of simulated microgravity in organisms.
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Affiliation(s)
- Peidang Liu
- Medical School, Southeast University, Nanjing, 210009, China
| | - Dan Li
- Medical School, Southeast University, Nanjing, 210009, China
| | - Wenjie Li
- Medical School, Southeast University, Nanjing, 210009, China
| | - Dayong Wang
- Medical School, Southeast University, Nanjing, 210009, China.
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83
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Mitophagy, Mitochondrial Dynamics, and Homeostasis in Cardiovascular Aging. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2019; 2019:9825061. [PMID: 31781358 PMCID: PMC6875274 DOI: 10.1155/2019/9825061] [Citation(s) in RCA: 125] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2019] [Accepted: 09/13/2019] [Indexed: 12/19/2022]
Abstract
Biological aging is an inevitable and independent risk factor for a wide array of chronic diseases including cardiovascular and metabolic diseases. Ample evidence has established a pivotal role for interrupted mitochondrial homeostasis in the onset and development of aging-related cardiovascular anomalies. A number of culprit factors have been suggested in aging-associated mitochondrial anomalies including oxidative stress, lipid toxicity, telomere shortening, metabolic disturbance, and DNA damage, with recent findings revealing a likely role for compromised mitochondrial dynamics and mitochondrial quality control machinery such as autophagy. Mitochondria undergo consistent fusion and fission, which are crucial for mitochondrial homeostasis and energy adaptation. Autophagy, in particular, mitochondria-selective autophagy, namely, mitophagy, refers to a highly conservative cellular process to degrade and clear long-lived or damaged cellular organelles including mitochondria, the function of which gradually deteriorates with increased age. Mitochondrial homeostasis could be achieved through a cascade of independent but closely related processes including fusion, fission, mitophagy, and mitochondrial biogenesis. With improved health care and increased human longevity, the ever-rising aging society has imposed a high cardiovascular disease prevalence. It is thus imperative to understand the role of mitochondrial homeostasis in the regulation of lifespan and healthspan. Targeting mitochondrial homeostasis should offer promising novel therapeutic strategies against aging-related complications, particularly cardiovascular diseases.
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84
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Functions, mechanisms and regulation of Pumilio/Puf family RNA binding proteins: a comprehensive review. Mol Biol Rep 2019; 47:785-807. [PMID: 31643042 DOI: 10.1007/s11033-019-05142-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 10/15/2019] [Indexed: 12/16/2022]
Abstract
The Pumilio (Pum)/Puf family proteins are ubiquitously present across eukaryotes, including yeast, plants and humans. They generally bind to the 3' untranslated regions of single stranded RNA targets in a sequence specific manner and destabilize them, although a few reports suggest their role in stabilizing the target transcripts. The Pum isoforms are implicated in a wide array of biological processes including stem cell maintenance, development, ribosome biogenesis as well as human diseases. Further studies on Pum would be interesting and important to understand their evolutionarily conserved and divergent features across species, which can have potential implications in medicine, plant sciences as well as basic molecular and cell biological studies. A large number of research reports exists, pertaining to various aspects of Pum, in individual experimental systems. This review is a comprehensive summary of the functions, types, mechanism of action as well as the regulation of Pum in various species. Also, the research questions to be addressed in future are discussed.
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85
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The Good and the Bad of Mitochondrial Breakups. Trends Cell Biol 2019; 29:888-900. [PMID: 31495461 DOI: 10.1016/j.tcb.2019.08.003] [Citation(s) in RCA: 108] [Impact Index Per Article: 21.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2019] [Revised: 08/08/2019] [Accepted: 08/12/2019] [Indexed: 12/14/2022]
Abstract
Mitochondrial morphology is a crucial determinant of mitochondrial and cellular function. Opposing fusion and fission events shape the tubular mitochondrial reticulum and ensure mitochondrial transport within cells. Cellular stress and pathophysiological conditions can lead to fragmentation of the mitochondrial network, which facilitates mitophagy and is associated with cell death. However, mitochondrial shape changes are also intertwined with the cellular metabolism, and metabolic switches can induce but also result from alterations in mitochondrial morphology. Here, we discuss recent advances in the field of mitochondrial dynamics, demonstrating cell- and tissue-specific effects of mitochondrial fragmentation on cellular metabolism, cell survival, and mitochondrial quality control.
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86
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Aparicio R, Rana A, Walker DW. Upregulation of the Autophagy Adaptor p62/SQSTM1 Prolongs Health and Lifespan in Middle-Aged Drosophila. Cell Rep 2019; 28:1029-1040.e5. [PMID: 31340141 PMCID: PMC6688777 DOI: 10.1016/j.celrep.2019.06.070] [Citation(s) in RCA: 83] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 04/21/2019] [Accepted: 06/19/2019] [Indexed: 01/27/2023] Open
Abstract
Autophagy, a lysosomal degradation pathway, plays crucial roles in health and disease. p62/SQSTM1 (hereafter p62) is an autophagy adaptor protein that can shuttle ubiquitinated cargo for autophagic degradation. Here, we show that upregulating the Drosophila p62 homolog ref(2)P/dp62, starting in midlife, delays the onset of pathology and prolongs healthy lifespan. Midlife induction of dp62 improves proteostasis, in aged flies, in an autophagy-dependent manner. Previous studies have reported that p62 plays a role in mediating the clearance of dysfunctional mitochondria via mitophagy. However, the causal relationships between p62 expression, mitochondrial homeostasis, and aging remain largely unexplored. We show that upregulating dp62, in midlife, promotes mitochondrial fission, facilitates mitophagy, and improves mitochondrial function in aged flies. Finally, we show that mitochondrial fission is required for the anti-aging effects of midlife dp62 induction. Our findings indicate that p62 represents a potential therapeutic target to counteract aging and prolong health in aged mammals.
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Affiliation(s)
- Ricardo Aparicio
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Anil Rana
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - David W Walker
- Department of Integrative Biology and Physiology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Molecular Biology Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA.
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87
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Bar-Ziv R, Nguyen NT, Dillin A. Vive ut Numquam Moriturus: Tweaking Translational Control to Regulate Longevity. Mol Cell 2019; 73:643-644. [PMID: 30794792 DOI: 10.1016/j.molcel.2019.02.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Molecular mechanisms regulating aging at the post-transcriptional level are not clear. In this issue of Molecular Cell,D'Amico et al. (2019) demonstrate that the translational inhibition of mitochondrial fission factor (MFF) regulates cellular homeostasis and aging.
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Affiliation(s)
- Raz Bar-Ziv
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Ngoc-Tram Nguyen
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Andrew Dillin
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA.
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88
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Pasipoularides A. Clinical-pathological correlations of BAV and the attendant thoracic aortopathies. Part 2: Pluridisciplinary perspective on their genetic and molecular origins. J Mol Cell Cardiol 2019; 133:233-246. [PMID: 31175858 DOI: 10.1016/j.yjmcc.2019.05.022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Revised: 05/10/2019] [Accepted: 05/27/2019] [Indexed: 12/30/2022]
Abstract
Bicuspid aortic valve (BAV) arises during valvulogenesis when 2 leaflets/cusps of the aortic valve (AOV) are fused together. Its clinical manifestations pertain to faulty AOV function, the associated aortopathy, and other complications surveyed in Part 1 of the present bipartite-series. Part 2 examines mainly genetic and epigenetic causes of BAV and BAV-associated aortopathies (BAVAs) and disease syndromes (BAVD). Part 1 explored the heterogeneity among subsets of patients with BAV and BAVA/BAVD, and investigated abnormal fluid dynamic stress and strain patterns sustained by the cusps. Specific BAV morphologies engender systolic outflow asymmetries, associated with abnormal aortic regional wall-shear-stress distributions and the expression/localization of BAVAs. Understanding fluid dynamic factors besides the developmental mechanisms and underlying genetics governing these congenital anomalies is necessary to explain patient predisposition to aortopathy and phenotypic heterogeneity. BAV aortopathy entails complex/multifactorial pathophysiology, involving alterations in genetics, epigenetics, hemodynamics, and in cellular and molecular pathways. There is always an interdependence between organismic developmental signals and genes-no systemic signals, no gene-expression; no active gene, no next step. An apposite signal induces the expression of the next developmental gene, which needs be expressed to trigger the next signal, and so on. Hence, embryonic, then post-partum, AOV and thoracic aortic development comprise cascades of developmental genes and their regulation. Interdependencies between them arise, entailing reciprocal/cyclical mutual interactions and adaptive feedback loops, by which developmental morphogenetic processes self-correct responding to environmental inputs/reactions. This Survey can serve as a reference point and driver for further pluridisciplinary BAV/BAVD studies and their clinical translation.
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Affiliation(s)
- Ares Pasipoularides
- Duke/NSF Center for Emerging Cardiovascular Technologies, Emeritus Faculty of Surgery and of Biomedical Engineering, Duke University School of Medicine and Graduate School, Durham, NC, USA.
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89
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Nikonova E, Kao SY, Ravichandran K, Wittner A, Spletter ML. Conserved functions of RNA-binding proteins in muscle. Int J Biochem Cell Biol 2019; 110:29-49. [PMID: 30818081 DOI: 10.1016/j.biocel.2019.02.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2018] [Revised: 02/21/2019] [Accepted: 02/23/2019] [Indexed: 12/13/2022]
Abstract
Animals require different types of muscle for survival, for example for circulation, motility, reproduction and digestion. Much emphasis in the muscle field has been placed on understanding how transcriptional regulation generates diverse types of muscle during development. Recent work indicates that alternative splicing and RNA regulation are as critical to muscle development, and altered function of RNA-binding proteins causes muscle disease. Although hundreds of genes predicted to bind RNA are expressed in muscles, many fewer have been functionally characterized. We present a cross-species view summarizing what is known about RNA-binding protein function in muscle, from worms and flies to zebrafish, mice and humans. In particular, we focus on alternative splicing regulated by the CELF, MBNL and RBFOX families of proteins. We discuss the systemic nature of diseases associated with loss of RNA-binding proteins in muscle, focusing on mis-regulation of CELF and MBNL in myotonic dystrophy. These examples illustrate the conservation of RNA-binding protein function and the marked utility of genetic model systems in understanding mechanisms of RNA regulation.
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Affiliation(s)
- Elena Nikonova
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Shao-Yen Kao
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Keshika Ravichandran
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Anja Wittner
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany
| | - Maria L Spletter
- Biomedical Center, Department of Physiological Chemistry, Ludwig-Maximilians-University München, Großhaderner Str. 9, 82152, Martinsried-Planegg, Germany; Center for Integrated Protein Science Munich (CIPSM) at the Department of Chemistry, Ludwig-Maximilians-Universität München, Munich, Germany.
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90
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Kopp F, Elguindy MM, Yalvac ME, Zhang H, Chen B, Gillett FA, Lee S, Sivakumar S, Yu H, Xie Y, Mishra P, Sahenk Z, Mendell JT. PUMILIO hyperactivity drives premature aging of Norad-deficient mice. eLife 2019; 8:42650. [PMID: 30735131 PMCID: PMC6407921 DOI: 10.7554/elife.42650] [Citation(s) in RCA: 58] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2018] [Accepted: 02/05/2019] [Indexed: 02/06/2023] Open
Abstract
Although numerous long noncoding RNAs (lncRNAs) have been identified, our understanding of their roles in mammalian physiology remains limited. Here, we investigated the physiologic function of the conserved lncRNA Norad in vivo. Deletion of Norad in mice results in genomic instability and mitochondrial dysfunction, leading to a dramatic multi-system degenerative phenotype resembling premature aging. Loss of tissue homeostasis in Norad-deficient animals is attributable to augmented activity of PUMILIO proteins, which act as post-transcriptional repressors of target mRNAs to which they bind. Norad is the preferred RNA target of PUMILIO2 (PUM2) in mouse tissues and, upon loss of Norad, PUM2 hyperactively represses key genes required for mitosis and mitochondrial function. Accordingly, enforced Pum2 expression fully phenocopies Norad deletion, resulting in rapid-onset aging-associated phenotypes. These findings provide new insights and open new lines of investigation into the roles of noncoding RNAs and RNA binding proteins in normal physiology and aging. Only a tiny portion of our genetic material contains the information required to create proteins, the workhorses of the body. The rest of our DNA, however, is not useless: some of it can be transcribed to create molecules known as non-coding RNAs, which are increasingly scrutinized by scientists. For example, a non-coding RNA called NORAD acts as a guardian of the genome by reducing the activity of a protein named PUMILIO. Without NORAD, PUMILIO becomes overactive, and this causes problems as genetic information is split between two ‘daughter cells’ when a cell divides. Defects in the amount of genetic material in cells have been linked with faster aging in animals. In addition, some studies suggest that as animals get older, the levels of NORAD in the body decrease, while the levels of PUMILIO increase. However, the precise role that NORAD may play in aging remains unclear. To address this question, Kopp et al. engineered mutant mice that lack Norad (the mouse equivalent of human NORAD) and carefully monitored how they grew and developed. The animals looked normal at birth, but they seemed to age faster: for instance, their fur became thin and gray, and their brains developed age-related abnormalities much sooner than normal mice. At the level of individual cells, losing Norad was also associated with problems often seen in old age. The mutant animals were more likely to have incorrect amounts of genetic information in their cells, and they had defects in the cell compartments that create the energy necessary for life. Further experiments showed that these issues were driven by PUMILIO being hyperactive. Overall, the work by Kopp et al. reveal that the non-coding RNA Norad is essential to keep PUMILIO activity in check and to prevent problems associated with aging from appearing in young animals. Further studies are now needed to take a closer look at how NORAD and other non-coding RNAs keep us healthy.
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Affiliation(s)
- Florian Kopp
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Mahmoud M Elguindy
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Mehmet E Yalvac
- Center for Gene Therapy, Nationwide Children's Hospital, Columbus, United States.,Department of Neurology, The Ohio State University, Columbus, United States
| | - He Zhang
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, United States
| | - Beibei Chen
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, United States
| | - Frank A Gillett
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Sungyul Lee
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Sushama Sivakumar
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States
| | - Hongtao Yu
- Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, United States.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - Yang Xie
- Quantitative Biomedical Research Center, University of Texas Southwestern Medical Center, Dallas, United States.,Department of Clinical Sciences, University of Texas Southwestern Medical Center, Dallas, United States.,Harold C Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, United States
| | - Prashant Mishra
- Children's Medical Center Research Institute, University of Texas Southwestern Medical Center, Dallas, United States
| | - Zarife Sahenk
- Center for Gene Therapy, Nationwide Children's Hospital, Columbus, United States.,Department of Pediatrics, The Ohio State University, Columbus, United States.,Department of Neurology, The Ohio State University, Columbus, United States
| | - Joshua T Mendell
- Department of Molecular Biology, University of Texas Southwestern Medical Center, Dallas, United States.,Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, United States.,Harold C Simmons Comprehensive Cancer Center, University of Texas Southwestern Medical Center, Dallas, United States.,Hamon Center for Regenerative Science and Medicine, University of Texas Southwestern Medical Center, Dallas, United States
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