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Verlhac P, Grégoire IP, Azocar O, Petkova DS, Baguet J, Viret C, Faure M. Autophagy receptor NDP52 regulates pathogen-containing autophagosome maturation. Cell Host Microbe 2015; 17:515-25. [PMID: 25771791 DOI: 10.1016/j.chom.2015.02.008] [Citation(s) in RCA: 109] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 11/04/2014] [Accepted: 01/23/2015] [Indexed: 02/03/2023]
Abstract
Xenophagy, an essential anti-microbial cell-autonomous mechanism, relies on the ability of the autophagic process to selectively entrap intracellular pathogens within autophagosomes to degrade them in autolysosomes. This selective targeting is carried out by specialized autophagy receptors, such as NDP52, but it is unknown whether the fusion of pathogen-containing autophagosomes with lysosomes is also regulated by pathogen-specific cellular factors. Here, we show that NDP52 also promotes the maturation of autophagosomes via its interaction with LC3A, LC3B, and/or GABARAPL2 through a distinct LC3-interacting region, and with MYOSIN VI. During Salmonella Typhimurium infection, the regulatory function of NDP52 in autophagosome maturation is complementary but independent of its function in pathogen targeting to autophagosomes, which relies on the interaction with LC3C. Thus, complete xenophagy is selectively regulated by a single autophagy receptor, which initially orchestrates bacteria targeting to autophagosomes and subsequently ensures pathogen degradation by regulating pathogen-containing autophagosome maturation.
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Affiliation(s)
- Pauline Verlhac
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Isabel P Grégoire
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Olga Azocar
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Denitsa S Petkova
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Joël Baguet
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Christophe Viret
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France
| | - Mathias Faure
- CIRI, International Center for Infectiology Research, Université de Lyon, 69007 Lyon, France; Inserm, U1111, 69007 Lyon, France; CNRS, UMR5308, 69007 Lyon, France; Ecole Normale Supérieure de Lyon, 69007 Lyon, France; Université Lyon 1, Centre International de Recherche en Infectiologie, 69007 Lyon, France.
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202
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Hasegawa J, Maejima I, Iwamoto R, Yoshimori T. Selective autophagy: Lysophagy. Methods 2015; 75:128-32. [DOI: 10.1016/j.ymeth.2014.12.014] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 12/11/2014] [Accepted: 12/15/2014] [Indexed: 01/13/2023] Open
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203
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Coughlin L, Morrison RS, Horner PJ, Inman DM. Mitochondrial morphology differences and mitophagy deficit in murine glaucomatous optic nerve. Invest Ophthalmol Vis Sci 2015; 56:1437-46. [PMID: 25655803 DOI: 10.1167/iovs.14-16126] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
PURPOSE Decreased ATP correlates with intraocular pressure exposure in the optic nerves of mice with glaucoma. To understand what underlies this energy deficit, we examined mitochondria in the myelinated optic nerve axons of the DBA/2J mouse, a model of glaucoma secondary to iris pigment disease, and the DBA/2(wt-gpnmb) control strain. METHODS Mitochondrial length, width, surface area, and health status were measured in 30 electron microscopic fields within the myelinated portion of optic nerves from DBA/2J and DBA/2(wt-gpnmb) mice at 3, 6, and 10 months of age. Protein was isolated from optic nerve for analysis of PINK1, Parkin, LC3-I and -II, and lysosome-associated membrane protein 1 (LAMP1) by Western blot. RESULTS The number of mitochondria in DBA/2J optic nerve was increased, and they had significantly smaller surface area. Mitochondria in DBA/2J were closer to the axolemma, more spatially isolated, and their cristae were more disrupted at every age group as compared to DBA/2(wt-gpnmb). Autophagosomes were significantly increased in DBA/2J optic nerve at all ages. Protein analysis showed higher LC3-II to LC3-I ratio in aged DBA/2J optic nerve than in DBA/2(wt-gpnmb). PINK1 and Parkin levels were not statistically different across age groups. LAMP1 was significantly decreased in the aged DBA/2J optic nerve. CONCLUSIONS Decreased surface area, combined with reduced oxidative capacity in mitochondria from the aged DBA/2J axon, indicate that mitochondrial pathology may contribute to the energy deficit in glaucomatous optic nerve. Though autophagosomes were increased in DBA/2J optic nerve, the increased mitochondria and decreased LAMP1 suggest deteriorating mitochondria are not being efficiently recycled by mitophagy.
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Affiliation(s)
- Lucy Coughlin
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, Ohio, United States School of Biomedical Sciences, Kent State University, Kent, Ohio, United States
| | - Richard S Morrison
- Department of Neurological Surgery, University of Washington, Seattle, Washington, United States
| | - Philip J Horner
- Department of Neurological Surgery, University of Washington, Seattle, Washington, United States
| | - Denise M Inman
- Department of Pharmaceutical Sciences, Northeast Ohio Medical University, Rootstown, Ohio, United States
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204
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Cohen LB, Troemel ER. Microbial pathogenesis and host defense in the nematode C. elegans. Curr Opin Microbiol 2015; 23:94-101. [PMID: 25461579 PMCID: PMC4324121 DOI: 10.1016/j.mib.2014.11.009] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 11/11/2014] [Accepted: 11/13/2014] [Indexed: 12/13/2022]
Abstract
Epithelial cells line the surfaces of the body, and are on the front lines of defense against microbial infection. Like many other metazoans, the nematode Caenorhabditis elegans lacks known professional immune cells and relies heavily on defense mediated by epithelial cells. New results indicate that epithelial defense in C. elegans can be triggered through detection of pathogen-induced perturbation of core physiology within host cells and through autophagic defense against intracellular and extracellular pathogens. Recent studies have also illuminated a diverse array of pathogenic attack strategies used against C. elegans. These findings are providing insight into the underpinnings of host/pathogen interactions in a simple animal host that can inform studies of infectious diseases in humans.
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Affiliation(s)
- Lianne B Cohen
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States
| | - Emily R Troemel
- Division of Biological Sciences, Section of Cell and Developmental Biology, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093, United States.
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205
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Autophagy inhibition re-sensitizes pulse stimulation-selected paclitaxel-resistant triple negative breast cancer cells to chemotherapy-induced apoptosis. Breast Cancer Res Treat 2015; 149:619-29. [PMID: 25638397 DOI: 10.1007/s10549-015-3283-9] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Accepted: 01/20/2015] [Indexed: 01/07/2023]
Abstract
Chemotherapy is the mainstay of systemic treatment for triple negative breast cancer (TNBC); however, the development of drug resistance limits its effectiveness. Therefore, we investigated the underlying mechanism for drug resistance and potential approaches to overcome it for a more effective treatment for TNBCs. Using a pulse-stimulated selection strategy to mimic chemotherapy administration in the clinic, we developed a new paclitaxel-resistant MDA-MB-231 cell line and analyzed these cells for changes in autophagy activity, and the role and mechanisms of the increased autophagy in promoting drug resistance were determined. We found that the pulse-stimulated selection strategy with paclitaxel resulted in MDA-MB-231 variant cells with enhanced resistance to paclitaxel. These resistant cells were found to have enhanced basal autophagy activity, which confers a cytoprotective function under paclitaxel treatment stress. Inhibition of autophagy enhanced paclitaxel-induced cell death in these paclitaxel-resistant cells. We further revealed that up-regulated autophagy in resistant cells enhanced the clearance of damaged mitochondria. Last, we showed that the paclitaxel-resistant cancer cells acquired cross resistance to epirubicin and cisplatin. Together, these results suggest that combining autophagy inhibition with chemotherapy may be an effective strategy to improve treatment outcome in paclitaxel-resistant TNBC patients.
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206
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Abstract
Defects in autophagy have been linked to a wide range of medical illnesses, including cancer as well as infectious, neurodegenerative, inflammatory, and metabolic diseases. These observations have led to the hypothesis that autophagy inducers may prevent or treat certain clinical conditions. Lifestyle and nutritional factors, such as exercise and caloric restriction, may exert their known health benefits through the autophagy pathway. Several currently available FDA-approved drugs have been shown to enhance autophagy, and this autophagy-enhancing action may be repurposed for use in novel clinical indications. The development of new drugs that are designed to be more selective inducers of autophagy function in target organs is expected to maximize clinical benefits while minimizing toxicity. This Review summarizes the rationale and current approaches for developing autophagy inducers in medicine, the factors to be considered in defining disease targets for such therapy, and the potential benefits of such treatment for human health.
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207
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Abstract
PURPOSE OF REVIEW Autophagy plays a crucial role in intracellular defense against various pathogens. Xenophagy is a form of selective autophagy that targets intracellular pathogens for degradation. In addition, several related, yet distinct, intracellular defense responses depend on autophagy-related genes. This review gives an overview of these processes, pathogen strategies to subvert them, and their crosstalk with various cell death programs. RECENT FINDINGS The recruitment of autophagy-related proteins plays a key role in multiple intracellular defense programs, specifically xenophagy, microtubule-associated protein 1 light chain 3 alpha (LC3)-associated phagocytosis, and the interferon gamma-mediated elimination of pathogens, such as Toxoplasma gondii and murine norovirus. Recent progress has revealed methods employed by pathogens to resist these intracellular defense mechanisms and/or persist in spite of them. The intracellular pathogen load can tip the balance between cell survival and cell death. Further, it was recently observed that LC3-associated phagocytosis is indispensable for the efficient clearance of dying cells. SUMMARY Autophagy-dependent and autophagy-related gene-dependent pathways are essential in intracellular defense against a broad range of pathogens.
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208
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Wauer T, Swatek KN, Wagstaff JL, Gladkova C, Pruneda JN, Michel MA, Gersch M, Johnson CM, Freund SMV, Komander D. Ubiquitin Ser65 phosphorylation affects ubiquitin structure, chain assembly and hydrolysis. EMBO J 2014; 34:307-25. [PMID: 25527291 PMCID: PMC4339119 DOI: 10.15252/embj.201489847] [Citation(s) in RCA: 231] [Impact Index Per Article: 23.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
The protein kinase PINK1 was recently shown to phosphorylate ubiquitin (Ub) on Ser65, and phosphoUb activates the E3 ligase Parkin allosterically. Here, we show that PINK1 can phosphorylate every Ub in Ub chains. Moreover, Ser65 phosphorylation alters Ub structure, generating two conformations in solution. A crystal structure of the major conformation resembles Ub but has altered surface properties. NMR reveals a second phosphoUb conformation in which β5-strand slippage retracts the C-terminal tail by two residues into the Ub core. We further show that phosphoUb has no effect on E1-mediated E2 charging but can affect discharging of E2 enzymes to form polyUb chains. Notably, UBE2R1- (CDC34), UBE2N/UBE2V1- (UBC13/UEV1A), TRAF6- and HOIP-mediated chain assembly is inhibited by phosphoUb. While Lys63-linked poly-phosphoUb is recognized by the TAB2 NZF Ub binding domain (UBD), 10 out of 12 deubiquitinases (DUBs), including USP8, USP15 and USP30, are impaired in hydrolyzing phosphoUb chains. Hence, Ub phosphorylation has repercussions for ubiquitination and deubiquitination cascades beyond Parkin activation and may provide an independent layer of regulation in the Ub system.
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Affiliation(s)
- Tobias Wauer
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Kirby N Swatek
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jane L Wagstaff
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | | | - Martin A Michel
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Malte Gersch
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | | | - Stefan M V Freund
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - David Komander
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
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209
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Bauckman KA, Owusu-Boaitey N, Mysorekar IU. Selective autophagy: xenophagy. Methods 2014; 75:120-7. [PMID: 25497060 DOI: 10.1016/j.ymeth.2014.12.005] [Citation(s) in RCA: 95] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Revised: 11/30/2014] [Accepted: 12/02/2014] [Indexed: 12/24/2022] Open
Abstract
Xenophagy is an autophagic phenomenon that specifically involves pathogens and other non-host entities. Although the understanding of the relationship between autophagosomes and invading organisms has grown significantly in the past decade, the exact steps to confirm xenophagy has been not been thoroughly defined. Here we describe a methodical approach to confirming autophagy, its interaction with bacterial invasion, as well as the specific type of autophagic formation (i.e. autophagosome, autolysosome, phagolysosome). Further, we argue that xenophagy is not limited to pathogen interaction with autophagosome, but also non-microbial entities such as iron.
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Affiliation(s)
- Kyle A Bauckman
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO, USA
| | - Nana Owusu-Boaitey
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO, USA
| | - Indira U Mysorekar
- Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO, USA; Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO, USA.
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210
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Sorbara MT, Girardin SE. Emerging themes in bacterial autophagy. Curr Opin Microbiol 2014; 23:163-70. [PMID: 25497773 DOI: 10.1016/j.mib.2014.11.020] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Revised: 11/25/2014] [Accepted: 11/26/2014] [Indexed: 10/24/2022]
Abstract
The role of autophagy in the control of intracellular bacterial pathogens, also known as xenophagy, is well documented. Here, we highlight recent advances in the field of xenophagy. We review the importance of bacterial targeting by ubiquitination, diacylglycerol (DAG) or proteins such as Nod1, Nod2, NDP52, p62, NBR1, optineurin, LRSAM1 and parkin in the process of xenophagy. The importance of metabolic sensors, such as mTOR and AMPK, in xenophagy induction is also discussed. We also review the in vitro and in vivo evidence that demonstrate a global role for xenophagy in the control of bacterial growth. Finally, the mechanisms evolved by bacteria to escape xenophagy are presented.
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Affiliation(s)
- Matthew T Sorbara
- Department of Immunology, University of Toronto, Toronto M5S 1A8, Canada
| | - Stephen E Girardin
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto M5S 1A8, Canada.
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211
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How and why to study autophagy in Drosophila: it's more than just a garbage chute. Methods 2014; 75:151-61. [PMID: 25481477 PMCID: PMC4358840 DOI: 10.1016/j.ymeth.2014.11.016] [Citation(s) in RCA: 86] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 11/21/2014] [Accepted: 11/24/2014] [Indexed: 01/30/2023] Open
Abstract
During the catabolic process of autophagy, cytoplasmic material is transported to the lysosome for degradation and recycling. This way, autophagy contributes to the homeodynamic turnover of proteins, lipids, nucleic acids, glycogen, and even whole organelles. Autophagic activity is increased by adverse conditions such as nutrient limitation, growth factor withdrawal and oxidative stress, and it generally protects cells and organisms to promote their survival. Misregulation of autophagy is likely involved in numerous human pathologies including aging, cancer, infections and neurodegeneration, so its biomedical relevance explains the still growing interest in this field. Here we discuss the different microscopy-based, biochemical and genetic methods currently available to study autophagy in various tissues of the popular model Drosophila. We show examples for results obtained in different assays, explain how to interpret these with regard to autophagic activity, and how to find out which step of autophagy a given gene product is involved in.
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212
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Abstract
PURPOSE OF REVIEW To highlight recent findings that identify an essential role for the cellular degradative pathway of autophagy in governing a balanced response to intestinal pathogens and commensals. RECENT FINDINGS Following the genetic association of autophagy with inflammatory bowel disease susceptibility, increasing evidence indicates that this pathway functions in various epithelial lineages to support the intestinal barrier. New studies are also revealing that autophagy proteins dictate the quality and magnitude of immune responses. Mouse models, in particular, suggest that autophagy and inflammatory bowel disease susceptibility genes regulate inflammatory responses to viruses, a finding that coincides with an increasing appreciation that viruses have intricate interactions with the host and the microbiota beyond the obvious host-pathogen relationship. SUMMARY Autophagy and other immunological or stress response pathways intersect in mucosal immunity to dictate the response to pathogenic and commensal agents. The development of novel treatment strategies, as well as prognostic and diagnostic tools for gastrointestinal disorders, will be greatly facilitated by a deeper understanding of these interactions at the cell type and microbe-specific manner, which includes less appreciated components of the microbiota, such as eukaryotic and prokaryotic viruses.
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213
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Abstract
Macrophages are a diverse population of phagocytic cells that reside in tissues throughout the body. At sites of infection, macrophages encounter and engulf invading microbes. Accordingly, macrophages possess specialized effector functions to kill or coordinate the elimination of their prey. Nevertheless, many intracellular bacterial pathogens preferentially replicate inside macrophages. Here we consider explanations for what we call "the macrophage paradox:" why do so many pathogenic bacteria replicate in the very cells equipped to destroy them? We ask whether replication in macrophages is an unavoidable fate that essentially defines a key requirement to be a pathogen. Conversely, we consider whether fundamental aspects of macrophage biology provide unique cellular or metabolic environments that pathogens can exploit. We conclude that resolution of the macrophage paradox requires acknowledgment of the richness and complexity of macrophages as a replicative niche.
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Affiliation(s)
- Jordan V Price
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA
| | - Russell E Vance
- Department of Molecular and Cell Biology, University of California, Berkeley, Berkeley, CA 94720, USA; Howard Hughes Medical Institute, University of California, Berkeley, Berkeley, CA 94720, USA.
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214
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Differentiation state-specific mitochondrial dynamic regulatory networks are revealed by global transcriptional analysis of the developing chicken lens. G3-GENES GENOMES GENETICS 2014; 4:1515-27. [PMID: 24928582 PMCID: PMC4132181 DOI: 10.1534/g3.114.012120] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The mature eye lens contains a surface layer of epithelial cells called the lens epithelium that requires a functional mitochondrial population to maintain the homeostasis and transparency of the entire lens. The lens epithelium overlies a core of terminally differentiated fiber cells that must degrade their mitochondria to achieve lens transparency. These distinct mitochondrial populations make the lens a useful model system to identify those genes that regulate the balance between mitochondrial homeostasis and elimination. Here we used an RNA sequencing and bioinformatics approach to identify the transcript levels of all genes expressed by distinct regions of the lens epithelium and maturing fiber cells of the embryonic Gallus gallus (chicken) lens. Our analysis detected more than 15,000 unique transcripts expressed by the embryonic chicken lens. Of these, more than 3000 transcripts exhibited significant differences in expression between lens epithelial cells and fiber cells. Multiple transcripts coding for separate mitochondrial homeostatic and degradation mechanisms were identified to exhibit preferred patterns of expression in lens epithelial cells that require mitochondria relative to lens fiber cells that require mitochondrial elimination. These included differences in the expression levels of metabolic (DUT, PDK1, SNPH), autophagy (ATG3, ATG4B, BECN1, FYCO1, WIPI1), and mitophagy (BNIP3L/NIX, BNIP3, PARK2, p62/SQSTM1) transcripts between lens epithelial cells and lens fiber cells. These data provide a comprehensive window into all genes transcribed by the lens and those mitochondrial regulatory and degradation pathways that function to maintain mitochondrial populations in the lens epithelium and to eliminate mitochondria in maturing lens fiber cells.
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215
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Abstract
Almost 20 years ago, the discovery that mitochondrial release of cytochrome c initiates a cascade that leads to cell death brought about a wholesale change in how cell biologists think of mitochondria. Formerly viewed as sites of biosynthesis and bioenergy production, these double membrane organelles could now be thought of as regulators of signal transduction. Within a few years, multiple other mitochondria-centric signaling mechanisms have been proposed, including release of reactive oxygen species and the scaffolding of signaling complexes on the outer mitochondrial membrane. It has also been shown that mitochondrial dysfunction causes induction of stress responses, bolstering the idea that mitochondria communicate their fitness to the rest of the cell. In the past decade, multiple new modes of mitochondrial signaling have been discovered. These include the release of metabolites, mitochondrial motility and dynamics, and interaction with other organelles such as endoplasmic reticulum in regulating signaling. Collectively these studies have established that mitochondria-dependent signaling has diverse physiological and pathophysiological outcomes. This review is a brief account of recent work in mitochondria-dependent signaling in the historical framework of the early studies.
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Affiliation(s)
- Navdeep S Chandel
- Section of Pulmonary and Critical Care Medicine, Department of Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA.
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