51
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The Role of Macroautophagy in T Cells. Immunology 2018. [DOI: 10.1016/b978-0-12-809819-6.00003-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/09/2022] Open
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52
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Vasileiou PVS, Mourouzis I, Pantos C. Principal Aspects Regarding the Maintenance of Mammalian Mitochondrial Genome Integrity. Int J Mol Sci 2017; 18:E1821. [PMID: 28829360 PMCID: PMC5578207 DOI: 10.3390/ijms18081821] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 08/11/2017] [Accepted: 08/14/2017] [Indexed: 12/11/2022] Open
Abstract
Mitochondria have emerged as key players regarding cellular homeostasis not only due to their contribution regarding energy production through oxidative phosphorylation, but also due to their involvement in signaling, ion regulation, and programmed cell death. Indeed, current knowledge supports the notion that mitochondrial dysfunction is a hallmark in the pathogenesis of various diseases. Mitochondrial biogenesis and function require the coordinated action of two genomes: nuclear and mitochondrial. Unfortunately, both intrinsic and environmental genotoxic insults constantly threaten the integrity of nuclear as well as mitochondrial DNA. Despite the extensive research that has been made regarding nuclear genome instability, the importance of mitochondrial genome integrity has only recently begun to be elucidated. The specific architecture and repair mechanisms of mitochondrial DNA, as well as the dynamic behavior that mitochondria exert regarding fusion, fission, and autophagy participate in mitochondrial genome stability, and therefore, cell homeostasis.
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Affiliation(s)
- Panagiotis V S Vasileiou
- Department of Basic Medical Sciences, Laboratory of Histology & Embryology, School of Medicine, National and Kapodistrian University of Athens, 75 MikrasAsias Avenue, Goudi, Athens 11527, Greece.
| | - Iordanis Mourouzis
- Department of Pharmacology, School of Medicine, National and Kapodistrian University of Athens, 75 MikrasAsias Avenue, Goudi, Athens 11527, Greece.
| | - Constantinos Pantos
- Department of Pharmacology, School of Medicine, National and Kapodistrian University of Athens, 75 MikrasAsias Avenue, Goudi, Athens 11527, Greece.
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53
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Wong YK, Zhang J, Hua ZC, Lin Q, Shen HM, Wang J. Recent advances in quantitative and chemical proteomics for autophagy studies. Autophagy 2017; 13:1472-1486. [PMID: 28820289 DOI: 10.1080/15548627.2017.1313944] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Macroautophagy/autophagy is an evolutionarily well-conserved cellular degradative process with important biological functions that is closely implicated in health and disease. In recent years, quantitative mass spectrometry-based proteomics and chemical proteomics have emerged as important tools for the study of autophagy, through large-scale unbiased analysis of the proteome or through highly specific and accurate analysis of individual proteins of interest. At present, a variety of approaches have been successfully applied, including (i) expression and interaction proteomics for the study of protein post-translational modifications, (ii) investigating spatio-temporal dynamics of protein synthesis and degradation, and (iii) direct determination of protein activity and profiling molecular targets in the autophagic process. In this review, we attempted to provide an overview of principles and techniques relevant to the application of quantitative and chemical proteomics methods to autophagy, and outline the current landscape as well as future outlook of these methods in autophagy research.
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Affiliation(s)
- Yin-Kwan Wong
- a Department of Physiology, Yong Loo Lin School of Medicine , National University of Singapore , Singapore
| | - Jianbin Zhang
- b Department of Oncology, Clinical Research Institute , Zhejiang Provincial People's Hospital , Hangzhou , China
| | - Zi-Chun Hua
- c Changzhou High-Tech Research Institute of Nanjing University and the State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences , Nanjing University , Nanjing , China
| | - Qingsong Lin
- d Department of Biological Sciences , National University of Singapore , Singapore
| | - Han-Ming Shen
- a Department of Physiology, Yong Loo Lin School of Medicine , National University of Singapore , Singapore.,e NUS Graduate School for Integrative Sciences and Engineering , National University of Singapore , Singapore
| | - Jigang Wang
- a Department of Physiology, Yong Loo Lin School of Medicine , National University of Singapore , Singapore.,c Changzhou High-Tech Research Institute of Nanjing University and the State Key Laboratory of Pharmaceutical Biotechnology, College of Life Sciences , Nanjing University , Nanjing , China
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54
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Qiu Y, Zheng Y, Wu KP, Schulman BA. Insights into links between autophagy and the ubiquitin system from the structure of LC3B bound to the LIR motif from the E3 ligase NEDD4. Protein Sci 2017; 26:1674-1680. [PMID: 28470758 DOI: 10.1002/pro.3186] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 04/26/2017] [Accepted: 04/27/2017] [Indexed: 11/09/2022]
Abstract
Members of the LC3/GABARAP family of ubiquitin-like proteins function during autophagy by serving as membrane linked protein-binding platforms. Their C-termini are physically attached to membranes through covalent linkage to primary amines on lipids such as phosphatidylethanolamine, while their ubiquitin-like fold domains bind "LIR" (LC3-Interacting Region) sequences found within an extraordinarily diverse array of proteins including regulators of autophagy, adaptors that recruit ubiquitinated cargoes to be degraded, and even proteins controlling processes at membranes that are not associated with autophagy. Recently, LC3/GABARAP proteins were found to bind the ubiquitin E3 ligase NEDD4 to influence ubiquitination associated with autophagy in human cell lines. Here, we use purified recombinant proteins to define LC3B interactions with a specific LIR sequence from NEDD4, present a crystal structure showing atomic details of the interaction, and show that LC3B-binding can steer intrinsic NEDD4 E3 ligase activity. The data provide detailed molecular insights underlying recruitment of an E3 ubiquitin ligase to phagophores during autophagy.
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Affiliation(s)
- Yu Qiu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, 38105
| | - Yumei Zheng
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, 38105.,Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, 38103
| | - Kuen-Phon Wu
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, 38105
| | - Brenda A Schulman
- Department of Structural Biology, St. Jude Children's Research Hospital, Memphis, Tennessee, 38105.,Department of Microbiology, Immunology and Biochemistry, University of Tennessee Health Science Center, Memphis, Tennessee, 38103.,Howard Hughes Medical Institute, St. Jude Children's Research Hospital, Memphis, Tennessee, 38105
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55
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Boudoures AL, Saben J, Drury A, Scheaffer S, Modi Z, Zhang W, Moley KH. Obesity-exposed oocytes accumulate and transmit damaged mitochondria due to an inability to activate mitophagy. Dev Biol 2017; 426:126-138. [PMID: 28438607 DOI: 10.1016/j.ydbio.2017.04.005] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 03/22/2017] [Accepted: 04/17/2017] [Indexed: 11/26/2022]
Abstract
Mitochondria are the most prominent organelle in the oocyte. Somatic cells maintain a healthy population of mitochondria by degrading damaged mitochondria via mitophagy, a specialized autophagy pathway. However, evidence from previous work investigating the more general macroautophagy pathway in oocytes suggests that mitophagy may not be active in the oocyte. This would leave the vast numbers of mitochondria - poised to be inherited by the offspring - vulnerable to damage. Here we test the hypothesis that inactive mitophagy in the oocyte underlies maternal transmission of dysfunctional mitochondria. To determine whether oocytes can complete mitophagy, we used either CCCP or AntimycinA to depolarize mitochondria and trigger mitophagy. After depolarization, we did not detect co-localization of mitochondria with autophagosomes and mitochondrial DNA copy number remained unchanged, indicating the non-functional mitochondrial population was not removed. To investigate the impact of an absence of mitophagy in oocytes with damaged mitochondria on offspring mitochondrial function, we utilized in vitro fertilization of high fat high sugar (HF/HS)-exposed oocytes, which have lower mitochondrial membrane potential and damaged mitochondria. Here, we demonstrate that blastocysts generated from HF/HS oocytes have decreased mitochondrial membrane potential, lower metabolites involved in ATP generation, and accumulation of PINK1, a mitophagy marker protein. This mitochondrial phenotype in the blastocyst mirrors the phenotype we show in HF/HS exposed oocytes. Taken together, these data suggest that the mechanisms governing oocyte mitophagy are fundamentally distinct from those governing somatic cell mitophagy and that the absence of mitophagy in the setting of HF/HS exposure contributes to the oocyte-to-blastocyst transmission of dysfunctional mitochondria.
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Affiliation(s)
- Anna L Boudoures
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Jessica Saben
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Andrea Drury
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Suzanne Scheaffer
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Zeel Modi
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Wendy Zhang
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Kelle H Moley
- Center for Reproductive and Health Sciences, Washington University in St. Louis, St. Louis, MO, USA.
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56
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Wen H, Zhan L, Chen S, Long L, Xu E. Rab7 may be a novel therapeutic target for neurologic diseases as a key regulator in autophagy. J Neurosci Res 2017; 95:1993-2004. [PMID: 28186670 DOI: 10.1002/jnr.24034] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 01/17/2017] [Accepted: 01/17/2017] [Indexed: 12/14/2022]
Affiliation(s)
- Haixia Wen
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University and Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China; Guangzhou China
| | - Lixuan Zhan
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University and Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China; Guangzhou China
| | - Siyuan Chen
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University and Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China; Guangzhou China
| | - Long Long
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University and Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China; Guangzhou China
| | - En Xu
- Institute of Neuroscience and Department of Neurology of the Second Affiliated Hospital of Guangzhou Medical University and Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China; Guangzhou China
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Williams JA, Zhao K, Jin S, Ding WX. New methods for monitoring mitochondrial biogenesis and mitophagy in vitro and in vivo. Exp Biol Med (Maywood) 2017; 242:781-787. [PMID: 28093935 DOI: 10.1177/1535370216688802] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Removal of damaged mitochondria through mitophagy is critical for maintaining cellular homeostasis and functions. Increasing evidence implicates mitophagy in red blood cell differentiation, neurodegeneration, macrophage-mediated inflammation, ischemia, adipogenesis, drug-induced tissue injury, and cancer. Considerable progress has been made toward understanding the biochemical mechanisms involved in mitophagy regulation. However, few reliable assays to monitor and quantify mitophagy have been developed, particularly in vivo. In this review, we summarize the recent development of three assays, MitoTimer, mt-Keima and mito-QC, for monitoring and quantifying mitophagy in cells and in animal tissues. We also discuss the advantages and limitations of these three assays when using them to monitor and quantify mitophagy. Impact statement Removal of damaged mitochondria through mitophagy is critical for maintaining cellular homeostasis and functions. However, reliable quantitative assays to monitor mitophagy, particularly in vivo, are just emerging. This review will summarize the current novel quantitative assays to monitor mitophagy in vivo.
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Affiliation(s)
- Jessica A Williams
- 1 Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Katrina Zhao
- 1 Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Shengkan Jin
- 2 Department of Pharmacology, Rutgers University-Robert Wood Johnson Medical School, Piscataway, NJ 08854, USA
| | - Wen-Xing Ding
- 1 Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
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59
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Autophagy-related proteins are functionally active in human spermatozoa and may be involved in the regulation of cell survival and motility. Sci Rep 2016; 6:33647. [PMID: 27633131 PMCID: PMC5025659 DOI: 10.1038/srep33647] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Accepted: 08/25/2016] [Indexed: 02/06/2023] Open
Abstract
Macroautophagy (hereafter autophagy) is an evolutionarily highly conserved cellular process that participates in the maintenance of intracellular homeostasis through the degradation of most long-lived proteins and entire organelles. Autophagy participates in some reproductive events; however, there are not reports regarding the role of autophagy in the regulation of sperm physiology. Hence, the aim of this study was to investigate whether autophagy-related proteins are present and functionally active in human spermatozoa. Proteins related to autophagy/mitophagy process (LC3, Atg5, Atg16, Beclin 1, p62, m-TOR, AMPKα 1/2, and PINK1) were present in human spermatozoa. LC3 colocalized with p62 in the middle piece of the spermatozoa. Autophagy activation induced a significant increase in motility and a decrease in PINK1, TOM20 expression and caspase 3/7 activation. In contrast, autophagy inhibition resulted in decreased motility, viability, ATP and intracellular calcium concentration whereas PINK1, TOM20 expression, AMPK phosphorylation and caspase 3/7 activation were significantly increased. In conclusion our results show that autophagy related proteins and upstream regulators are present and functional in human spermatozoa. Modification of mitochondrial proteins expression after autophagy activation/inhibition may be indicating that a specialized form of autophagy named mitophagy may be regulating sperm function such as motility and viability and may be cooperating with apoptosis.
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60
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Rüb C, Wilkening A, Voos W. Mitochondrial quality control by the Pink1/Parkin system. Cell Tissue Res 2016; 367:111-123. [PMID: 27586587 DOI: 10.1007/s00441-016-2485-8] [Citation(s) in RCA: 90] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2016] [Accepted: 08/05/2016] [Indexed: 02/08/2023]
Abstract
Mitochondrial dysfunction represents a prominent pathological feature in many neurodegenerative diseases, particularly in Parkinson's disease (PD). Mutations in the genes encoding the proteins Pink1 and Parkin have been identified as genetic risk factors in familiar cases of PD. Research during the last decade has identified both proteins as crucial components of an organellar quality control system that contributes to the maintenance of mitochondrial function in healthy cells. The Pink1/Parkin system acts as a sensor for mitochondrial quality and is activated, in particular, after the loss of the electric potential across the inner mitochondrial membrane. Pink1 molecules accumulate at the surface of damaged mitochondria to recruit and activate Parkin, which, in turn, elicits a signaling pathway eventually leading to the autophagic removal of the damaged organelles. This review summarizes recent advances in our knowledge of the functional role of the Pink1/Parkin system in preventing the accumulation of damaged mitochondria by mitophagy.
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Affiliation(s)
- Cornelia Rüb
- Institut für Biochemie und Molekularbiologie (IBMB), Universität Bonn, Nussallee 11, 53115, Bonn, Germany
| | - Anne Wilkening
- Institut für Biochemie und Molekularbiologie (IBMB), Universität Bonn, Nussallee 11, 53115, Bonn, Germany
| | - Wolfgang Voos
- Institut für Biochemie und Molekularbiologie (IBMB), Universität Bonn, Nussallee 11, 53115, Bonn, Germany.
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61
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Ktistakis NT, Tooze SA. Digesting the Expanding Mechanisms of Autophagy. Trends Cell Biol 2016; 26:624-635. [PMID: 27050762 DOI: 10.1016/j.tcb.2016.03.006] [Citation(s) in RCA: 264] [Impact Index Per Article: 33.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Revised: 03/03/2016] [Accepted: 03/14/2016] [Indexed: 12/17/2022]
Abstract
Autophagy is a catabolic 'self-eating' pathway that is emerging as a crucial integration point in cell physiology. With its own set of genes, the autophagy pathway communicates with virtually all signalling networks and organelles. Recent advances have been made in understanding the origin of the autophagosomal membrane, novel regulators, and the mechanisms by which specific intracellular membranes become autophagy substrates. New studies on noncanonical autophagy, mediated by subsets of autophagy proteins, and the role of autophagy proteins in non-autophagy pathways are also emerging in many different biological contexts. Our understanding of canonical autophagy, including membrane origin and autophagy proteins, needs to be considered together with emerging noncanonical pathways.
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Affiliation(s)
| | - Sharon A Tooze
- Molecular Cell Biology of Autophagy, Francis Crick Institute, London, UK.
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62
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Suzuki A, Kakisaka K, Suzuki Y, Wang T, Takikawa Y. c-Jun N-terminal kinase-mediated Rubicon expression enhances hepatocyte lipoapoptosis and promotes hepatocyte ballooning. World J Gastroenterol 2016; 22:6509-6519. [PMID: 27605885 PMCID: PMC4968130 DOI: 10.3748/wjg.v22.i28.6509] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/24/2016] [Accepted: 06/13/2016] [Indexed: 02/06/2023] Open
Abstract
AIM: To clarify the relationship between autophagy and lipotoxicity-induced apoptosis, which is termed “lipoapoptosis,” in non-alcoholic steatohepatitis.
METHODS: Male C57BL/6J mice were fed a high-fat diet (HFD) for 12 wk, after which the liver histology and expression of proteins such as p62 or LC3 were evaluated. Alpha mouse liver 12 (AML12) cells treated with palmitate (PA) were used as an in vitro model.
RESULTS: LC3-II, p62, and Run domain Beclin-1 interacting and cysteine-rich containing (Rubicon) proteins increased in both the HFD mice and in AML12 cells in response to PA treatment. Rubicon expression was decreased upon c-Jun N-terminal kinase (JNK) inhibition at both the mRNA and the protein level in AML12 cells. Rubicon knockdown in AML12 cells with PA decreased the protein levels of both LC3-II and p62. Rubicon expression peaked at 4 h of PA treatment in AML12, and then decreased. Treatment with caspase-9 inhibitor ameliorated the decrease in Rubicon protein expression at 10 h of PA and resulted in enlarged AML12 cells under PA treatment. The enlargement of AML12 cells by PA with caspase-9 inhibition was canceled by Rubicon knockdown.
CONCLUSION: The JNK-Rubicon axis enhanced lipoapoptosis, and caspase-9 inhibition and Rubicon had effects that were cytologically similar to hepatocyte ballooning. As ballooned hepatocytes secrete fibrogenic signals and thus might promote fibrosis in the liver, the inhibition of hepatocyte ballooning might provide anti-fibrosis in the NASH liver.
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63
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McLelland GL, Lee SA, McBride HM, Fon EA. Syntaxin-17 delivers PINK1/parkin-dependent mitochondrial vesicles to the endolysosomal system. J Cell Biol 2016; 214:275-91. [PMID: 27458136 PMCID: PMC4970327 DOI: 10.1083/jcb.201603105] [Citation(s) in RCA: 172] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 06/21/2016] [Indexed: 12/14/2022] Open
Abstract
Vesicular transport from mitochondria to lysosomes is an emerging mitochondrial quality control mechanism. Here, McLelland et al. identify how mitochondrial vesicles are targeted for degradation, showing that syntaxin-17 is recruited to these structures to govern their SNARE-dependent fusion with endolysosomes. Mitochondria are considered autonomous organelles, physically separated from endocytic and biosynthetic pathways. However, recent work uncovered a PINK1/parkin-dependent vesicle transport pathway wherein oxidized or damaged mitochondrial content are selectively delivered to the late endosome/lysosome for degradation, providing evidence that mitochondria are indeed integrated within the endomembrane system. Given that mitochondria have not been shown to use canonical soluble NSF attachment protein receptor (SNARE) machinery for fusion, the mechanism by which mitochondrial-derived vesicles (MDVs) are targeted to the endosomal compartment has remained unclear. In this study, we identify syntaxin-17 as a core mitochondrial SNARE required for the delivery of stress-induced PINK1/parkin-dependent MDVs to the late endosome/lysosome. Syntaxin-17 remains associated with mature MDVs and forms a ternary SNARE complex with SNAP29 and VAMP7 to mediate MDV–endolysosome fusion in a manner dependent on the homotypic fusion and vacuole protein sorting (HOPS) tethering complex. Syntaxin-17 can be traced to the last eukaryotic common ancestor, hinting that the removal of damaged mitochondrial content may represent one of the earliest vesicle transport routes in the cell.
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Affiliation(s)
- Gian-Luca McLelland
- McGill Parkinson Program, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada Neurodegenerative Diseases Group, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Sydney A Lee
- McGill Parkinson Program, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada Neurodegenerative Diseases Group, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Heidi M McBride
- Rare Diseases Group, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada
| | - Edward A Fon
- McGill Parkinson Program, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada Neurodegenerative Diseases Group, Montreal Neurological Institute, McGill University, Montreal, Quebec H3A 2B4, Canada
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64
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McWilliams TG, Prescott AR, Allen GFG, Tamjar J, Munson MJ, Thomson C, Muqit MMK, Ganley IG. mito-QC illuminates mitophagy and mitochondrial architecture in vivo. J Cell Biol 2016; 214:333-45. [PMID: 27458135 PMCID: PMC4970326 DOI: 10.1083/jcb.201603039] [Citation(s) in RCA: 326] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Accepted: 07/06/2016] [Indexed: 11/22/2022] Open
Abstract
Whether mitophagy occurs within specific cellular subtypes in vivo is unclear. McWilliams et al. present “mito-QC,” a transgenic mouse containing a pH-sensitive fluorescent mitochondrial signal, allowing in vivo detection of mitophagy and mitochondrial morphology at single-cell resolution. Autophagic turnover of mitochondria, termed mitophagy, is proposed to be an essential quality-control (QC) mechanism of pathophysiological relevance in mammals. However, if and how mitophagy proceeds within specific cellular subtypes in vivo remains unclear, largely because of a lack of tractable tools and models. To address this, we have developed “mito-QC,” a transgenic mouse with a pH-sensitive fluorescent mitochondrial signal. This allows the assessment of mitophagy and mitochondrial architecture in vivo. Using confocal microscopy, we demonstrate that mito-QC is compatible with classical and contemporary techniques in histochemistry and allows unambiguous in vivo detection of mitophagy and mitochondrial morphology at single-cell resolution within multiple organ systems. Strikingly, our model uncovers highly enriched and differential zones of mitophagy in the developing heart and within specific cells of the adult kidney. mito-QC is an experimentally advantageous tool of broad relevance to cell biology researchers within both discovery-based and translational research communities.
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Affiliation(s)
- Thomas G McWilliams
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Alan R Prescott
- Division of Cell Signalling and Immunology, University of Dundee, Dundee DD1 9SY, Scotland, UK Dundee Imaging Facility, School of Life Sciences, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - George F G Allen
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Jevgenia Tamjar
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Michael J Munson
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Calum Thomson
- Dundee Imaging Facility, School of Life Sciences, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Miratul M K Muqit
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK School of Medicine, University of Dundee, Dundee DD1 9SY, Scotland, UK
| | - Ian G Ganley
- Medical Research Council Protein Phosphorylation and Ubiquitylation Unit, University of Dundee, Dundee DD1 9SY, Scotland, UK
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65
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Wu TT, Li WM, Yao YM. Interactions between Autophagy and Inhibitory Cytokines. Int J Biol Sci 2016; 12:884-97. [PMID: 27313501 PMCID: PMC4910606 DOI: 10.7150/ijbs.15194] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 05/12/2016] [Indexed: 02/06/2023] Open
Abstract
Autophagy is a degradative pathway that plays an essential role in maintaining cellular homeostasis. Most early studies of autophagy focused on its involvement in age-associated degeneration and nutrient deprivation. However, the immunological functions of autophagy have become more widely studied in recent years. Autophagy has been shown to be an intrinsic cellular defense mechanism in the innate and adaptive immune responses. Cytokines belong to a broad and loose category of proteins and are crucial for innate and adaptive immunity. Inhibitory cytokines have evolved to permit tolerance to self while also contributing to the eradication of invading pathogens. Interactions between inhibitory cytokines and autophagy have recently been reported, revealing a novel mechanism by which autophagy controls the immune response. In this review, we discuss interactions between autophagy and the regulatory cytokines IL-10, transforming growth factor-β, and IL-27. We also mention possible interactions between two newly discovered cytokines, IL-35 and IL-37, and autophagy.
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Affiliation(s)
- Tian-Tian Wu
- 1. Department of Hepatobiliary Surgery, the 309th Hospital of Chinese PLA, Beijing 100091, People's Republic of China
| | - Wei-Min Li
- 1. Department of Hepatobiliary Surgery, the 309th Hospital of Chinese PLA, Beijing 100091, People's Republic of China
| | - Yong-Ming Yao
- 2. Trauma Research Center, First Hospital Affiliated to the Chinese PLA General Hospital, Beijing 100048, People's Republic of China; 3. State Key Laboratory of Kidney Disease, the Chinese PLA General Hospital, Beijing 100853, People's Republic of China
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66
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Agarwal S, Yadav A, Tiwari SK, Seth B, Chauhan LKS, Khare P, Ray RS, Chaturvedi RK. Dynamin-related Protein 1 Inhibition Mitigates Bisphenol A-mediated Alterations in Mitochondrial Dynamics and Neural Stem Cell Proliferation and Differentiation. J Biol Chem 2016; 291:15923-39. [PMID: 27252377 DOI: 10.1074/jbc.m115.709493] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2015] [Indexed: 11/06/2022] Open
Abstract
The regulatory dynamics of mitochondria comprises well orchestrated distribution and mitochondrial turnover to maintain the mitochondrial circuitry and homeostasis inside the cells. Several pieces of evidence suggested impaired mitochondrial dynamics and its association with the pathogenesis of neurodegenerative disorders. We found that chronic exposure of synthetic xenoestrogen bisphenol A (BPA), a component of consumer plastic products, impaired autophagy-mediated mitochondrial turnover, leading to increased oxidative stress, mitochondrial fragmentation, and apoptosis in hippocampal neural stem cells (NSCs). It also inhibited hippocampal derived NSC proliferation and differentiation, as evident by the decreased number of BrdU- and β-III tubulin-positive cells. All these effects were reversed by the inhibition of oxidative stress using N-acetyl cysteine. BPA up-regulated the levels of Drp-1 (dynamin-related protein 1) and enhanced its mitochondrial translocation, with no effect on Fis-1, Mfn-1, Mfn-2, and Opa-1 in vitro and in the hippocampus. Moreover, transmission electron microscopy studies suggested increased mitochondrial fission and accumulation of fragmented mitochondria and decreased elongated mitochondria in the hippocampus of the rat brain. Impaired mitochondrial dynamics by BPA resulted in increased reactive oxygen species and malondialdehyde levels, disruption of mitochondrial membrane potential, and ATP decline. Pharmacological (Mdivi-1) and genetic (Drp-1siRNA) inhibition of Drp-1 reversed BPA-induced mitochondrial dysfunctions, fragmentation, and apoptosis. Interestingly, BPA-mediated inhibitory effects on NSC proliferation and neuronal differentiations were also mitigated by Drp-1 inhibition. On the other hand, Drp-1 inhibition blocked BPA-mediated Drp-1 translocation, leading to decreased apoptosis of NSC. Overall, our studies implicate Drp-1 as a potential therapeutic target against BPA-mediated impaired mitochondrial dynamics and neurodegeneration in the hippocampus.
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Affiliation(s)
- Swati Agarwal
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and the Academy of Scientific and Innovative Research and
| | - Anuradha Yadav
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and the Academy of Scientific and Innovative Research and
| | - Shashi Kant Tiwari
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and the Academy of Scientific and Innovative Research and
| | - Brashket Seth
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and the Academy of Scientific and Innovative Research and
| | - Lalit Kumar Singh Chauhan
- the Central Instrumentation Facility, Council of Scientific and Industrial Research-Indian Institute of Toxicology Research (CSIR-IITR), Vishvigyan Bhawan, 31, Mahatma Gandhi Marg, Lucknow 226001, Uttar Pradesh, India
| | - Puneet Khare
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and
| | - Ratan Singh Ray
- the Photobiology Laboratory, Systems Toxicology and Health Risk Assessment Group
| | - Rajnish Kumar Chaturvedi
- From the Developmental Toxicology Laboratory, Systems Toxicology and Health Risk Assessment Group and the Academy of Scientific and Innovative Research and
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Abstract
Sirt1 is the most prominent and extensively studied member of sirtuins, the family of mammalian class III histone deacetylases heavily implicated in health span and longevity. Although primarily a nuclear protein, Sirt1's deacetylation of Peroxisome proliferator-activated receptor Gamma Coactivator-1α (PGC-1α) has been extensively implicated in metabolic control and mitochondrial biogenesis, which was proposed to partially underlie Sirt1's role in caloric restriction and impacts on longevity. The notion of Sirt1's regulation of PGC-1α activity and its role in mitochondrial biogenesis has, however, been controversial. Interestingly, Sirt1 also appears to be important for the turnover of defective mitochondria by mitophagy. I discuss here evidences for Sirt1's regulation of mitochondrial biogenesis and turnover, in relation to PGC-1α deacetylation and various aspects of cellular physiology and disease.
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Affiliation(s)
- Bor Luen Tang
- Department of Biochemistry, Yong Loo Lin School of Medicine, National University of Singapore, 8 Medical Drive, Singapore 117597,
Singapore
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68
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Kaushal GP, Shah SV. Autophagy in acute kidney injury. Kidney Int 2016; 89:779-91. [PMID: 26924060 DOI: 10.1016/j.kint.2015.11.021] [Citation(s) in RCA: 273] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 11/12/2015] [Accepted: 11/19/2015] [Indexed: 02/09/2023]
Abstract
Autophagy is a conserved multistep pathway that degrades and recycles damaged organelles and macromolecules to maintain intracellular homeostasis. The autophagy pathway is upregulated under stress conditions including cell starvation, hypoxia, nutrient and growth-factor deprivation, endoplasmic reticulum stress, and oxidant injury, most of which are involved in the pathogenesis of acute kidney injury (AKI). Recent studies demonstrate that basal autophagy in the kidney is vital for the normal homeostasis of the proximal tubules. Deletion of key autophagy proteins impaired renal function and increased p62 levels and oxidative stress. In models of AKI, autophagy deletion in proximal tubules worsened tubular injury and renal function, highlighting that autophagy is renoprotective in models of AKI. In addition to nonselective sequestration of autophagic cargo, autophagy can facilitate selective degradation of damaged organelles, particularly mitochondrial degradation through the process of mitophagy. Damaged mitochondria accumulate in autophagy-deficient kidneys of mice subjected to ischemia-reperfusion injury, but the precise mechanisms of regulation of mitophagy in AKI are not yet elucidated. Recent progress in identifying the interplay of autophagy, apoptosis, and regulated necrosis has revived interest in examining shared pathways/molecules in this crosstalk during the pathogenesis of AKI. Autophagy and its associated pathways pose potentially unique targets for therapeutic interventions in AKI.
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Affiliation(s)
- Gur P Kaushal
- Renal Section, Medicine Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, USA; Division of Nephrology, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.
| | - Sudhir V Shah
- Renal Section, Medicine Service, Central Arkansas Veterans Healthcare System, Little Rock, Arkansas, USA; Division of Nephrology, Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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69
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Costa L, Amaral C, Teixeira N, Correia-da-Silva G, Fonseca BM. Cannabinoid-induced autophagy: Protective or death role? Prostaglandins Other Lipid Mediat 2015; 122:54-63. [PMID: 26732541 DOI: 10.1016/j.prostaglandins.2015.12.006] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 12/07/2015] [Accepted: 12/21/2015] [Indexed: 12/11/2022]
Abstract
Autophagy, the "self-digestion" mechanism of the cells, is an evolutionary conserved catabolic process that targets portions of cytoplasm, damaged organelles and proteins for lysosomal degradation, which plays a crucial role in development and disease. Cannabinoids are active compounds of Cannabis sativa and the most prevalent psychoactive substance is Δ(9)-tetrahydrocannabinol (THC). Cannabinoid compounds can be divided in three types: the plant-derived natural products (phytocannabinoids), the cannabinoids produced endogenously (endocannabinoids) and the synthesized compounds (synthetic cannabinoids). Various studies reported a cannabinoid-induced autophagy mechanism in cancer and non-cancer cells. In this review we focus on the recent advances in the cannabinoid-induced autophagy and highlight the molecular mechanisms involved in these processes.
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Affiliation(s)
- Lia Costa
- Departamento de Biologia, Universidade de Aveiro, Portugal; UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Cristina Amaral
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Natércia Teixeira
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Georgina Correia-da-Silva
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal
| | - Bruno M Fonseca
- UCIBIO, REQUIMTE, Laboratório de Bioquímica, Departamento de Ciências Biológicas, Faculdade de Farmácia, Universidade do Porto, Portugal.
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70
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Ha J, Guan KL, Kim J. AMPK and autophagy in glucose/glycogen metabolism. Mol Aspects Med 2015; 46:46-62. [PMID: 26297963 DOI: 10.1016/j.mam.2015.08.002] [Citation(s) in RCA: 150] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 08/04/2015] [Indexed: 12/14/2022]
Abstract
Glucose/glycogen metabolism is a primary metabolic pathway acting on a variety of cellular needs, such as proliferation, growth, and survival against stresses. The multiple regulatory mechanisms underlying a specific metabolic fate have been documented and explained the molecular basis of various pathophysiological conditions, including metabolic disorders and cancers. AMP-activated protein kinase (AMPK) has been appreciated for many years as a central metabolic regulator to inhibit energy-consuming pathways as well as to activate the compensating energy-producing programs. In fact, glucose starvation is a potent physiological AMPK activating condition, in which AMPK triggers various subsequent metabolic events depending on cells or tissues. Of note, the recent studies show bidirectional interplay between AMPK and glycogen. A growing number of studies have proposed additional level of metabolic regulation by a lysosome-dependent catabolic program, autophagy. Autophagy is a critical degradative pathway not only for maintenance of cellular homeostasis to remove potentially dangerous constituents, such as protein aggregates and dysfunctional subcellular organelles, but also for adaptive responses to metabolic stress, such as nutrient starvation. Importantly, many lines of evidence indicate that autophagy is closely connected with nutrient signaling modules, including AMPK, to fine-tune the metabolic pathways in response to many different cellular cues. In this review, we introduce the studies demonstrating the role of AMPK and autophagy in glucose/glycogen metabolism. Also, we describe the recent advances on their contributions to the metabolic disorders.
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Affiliation(s)
- Joohun Ha
- Department of Biochemistry and Molecular Biology, Medical Research Center and Biomedical Science Institute, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Kun-Liang Guan
- Department of Pharmacology, Moores Cancer Center, University of California, San Diego, La Jolla, CA 92093, USA.
| | - Joungmok Kim
- Department of Oral Biochemistry and Molecular Biology, Research Center for Tooth and Periodontal Tissue Regeneration, School of Dentistry, Kyung Hee University, Seoul, Republic of Korea.
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Armand L, Biola-Clier M, Bobyk L, Collin-Faure V, Diemer H, Strub JM, Cianferani S, Van Dorsselaer A, Herlin-Boime N, Rabilloud T, Carriere M. Molecular responses of alveolar epithelial A549 cells to chronic exposure to titanium dioxide nanoparticles: A proteomic view. J Proteomics 2015; 134:163-173. [PMID: 26276045 DOI: 10.1016/j.jprot.2015.08.006] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Revised: 08/05/2015] [Accepted: 08/07/2015] [Indexed: 12/22/2022]
Abstract
UNLABELLED Although the biological effects of titanium dioxide nanoparticles (TiO2-NPs) have been studied for more than two decades, the mechanisms governing their toxicity are still unclear. We applied 2D-gel proteomics analysis on A549 epithelial alveolar cells chronically exposed for 2months to 2.5 or 50μg/mL of deeply characterized TiO2-NPs, in order to obtain comprehensive molecular responses that may reflect functional outcomes. We show that exposure to TiO2-NPs impacts the abundance of 30 protein species, corresponding to 22 gene products. These proteins are involved in glucose metabolism, trafficking, gene expression, mitochondrial function, proteasome activity and DNA damage response. Besides, our results suggest that p53 pathway is activated, slowing down cell cycle progression and reducing cell proliferation rate. Moreover, we report increased content of chaperones-related proteins, which suggests homeostasis re-establishment. Finally, our results highlight that chronic exposure to TiO2-NPs affects the same cellular functions as acute exposure to TiO2-NPs, although lower exposure concentrations and longer exposure times induce more intense cellular response. BIOLOGICAL SIGNIFICANCE Our results make possible the identification of new mechanisms that explain TiO2-NP toxicity upon long-term, in vitro exposure of A549 cells. It is the first article describing -omics results obtained with this experimental strategy. We show that this long-term exposure modifies the cellular content of proteins involved in functions including mitochondrial activity, intra- and extracellular trafficking, proteasome activity, glucose metabolism, and gene expression. Moreover we observe modification of content of proteins that activate the p53 pathway, which suggest the induction of a DNA damage response. Technically, our results show that exposure of A549 cells to a high concentration of TiO2-NPs leads to the identification of modulations of the same functional categories than exposure to low, more realistic concentrations. Still the intensity differs between these two exposure scenarios. We also show that chronic exposure to TiO2-NPs induces the modulation of cellular functions that have already been reported in the literature as being impacted in acute exposure scenarios. This proves that the exposure protocol in in vitro experiments related to nanoparticle toxicology might be cautiously chosen since inappropriate scenario may lead to inappropriate and/or incomplete conclusions.
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Affiliation(s)
- Lucie Armand
- Université Grenoble-Alpes, INAC-LCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38000 Grenoble, France; CEA, INAC-SCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Mathilde Biola-Clier
- Université Grenoble-Alpes, INAC-LCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38000 Grenoble, France; CEA, INAC-SCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Laure Bobyk
- Université Grenoble-Alpes, INAC-LCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38000 Grenoble, France; CEA, INAC-SCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38054 Grenoble, France
| | - Véronique Collin-Faure
- CEA Grenoble, iRTSV/CBM, Laboratory of Chemistry and Biology of Metals, Grenoble, France
| | - Hélène Diemer
- Laboratoire de Spectrométrie de Masse BioOrganique (LSMBO), Université de Strasbourg, IPHC, 25 rue Becquerel 67087 Strasbourg, France; CNRS, UMR7178, 67037 Strasbourg, France
| | - Jean-Marc Strub
- Laboratoire de Spectrométrie de Masse BioOrganique (LSMBO), Université de Strasbourg, IPHC, 25 rue Becquerel 67087 Strasbourg, France; CNRS, UMR7178, 67037 Strasbourg, France
| | - Sarah Cianferani
- Laboratoire de Spectrométrie de Masse BioOrganique (LSMBO), Université de Strasbourg, IPHC, 25 rue Becquerel 67087 Strasbourg, France; CNRS, UMR7178, 67037 Strasbourg, France
| | - Alain Van Dorsselaer
- Laboratoire de Spectrométrie de Masse BioOrganique (LSMBO), Université de Strasbourg, IPHC, 25 rue Becquerel 67087 Strasbourg, France; CNRS, UMR7178, 67037 Strasbourg, France
| | | | - Thierry Rabilloud
- CNRS UMR 5249, Laboratory of Chemistry and Biology of Metals, Grenoble, France.
| | - Marie Carriere
- Université Grenoble-Alpes, INAC-LCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38000 Grenoble, France; CEA, INAC-SCIB, Laboratoire Lésions des Acides Nucléiques, 17 rue des Martyrs, F-38054 Grenoble, France.
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Xu Z, Yang L, Xu S, Zhang Z, Cao Y. The receptor proteins: pivotal roles in selective autophagy. Acta Biochim Biophys Sin (Shanghai) 2015; 47:571-80. [PMID: 26112016 DOI: 10.1093/abbs/gmv055] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2015] [Accepted: 03/30/2015] [Indexed: 02/05/2023] Open
Abstract
Autophagy is a highly regulated and multistep biological process whereby cells under metabolic, proteotoxic, or other stresses remove dysfunctional organelles and/or misfolded/polyubiquitinated proteins by shuttling them via specialized structures called autophagosomes to the lysosome for degradation. Although autophagy is generally considered to be a non-selective process, accumulating evidence suggests that it can also selectively degrade specific target cargoes. These selective targets include proteins, mitochondria, and even invading bacteria. The discovery and characterization of autophagic adapters, such as p62/Sequestosome 1 (SQSTM1) and Neighbor of BRCA1 gene 1 (NBR1), have provided mechanistic insights into selective autophagy. These receptors are all able to act as cargo receptors for the degradation of ubiquitinated substrates. This review mainly summarizes the most up-to-date findings regarding the key receptor proteins that play important roles in regulating selective autophagy.
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Affiliation(s)
- Zhijie Xu
- Cancer Research Institute, Central South University, Changsha 410078, China Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha 410078, China Key Laboratory of Carcinogenesis, Ministry of Health, Changsha 410078, China
| | - Lifang Yang
- Cancer Research Institute, Central South University, Changsha 410078, China Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha 410078, China Key Laboratory of Carcinogenesis, Ministry of Health, Changsha 410078, China
| | - San Xu
- Cancer Research Institute, Central South University, Changsha 410078, China Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha 410078, China Key Laboratory of Carcinogenesis, Ministry of Health, Changsha 410078, China
| | - Zhibao Zhang
- Cancer Research Institute, Central South University, Changsha 410078, China Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha 410078, China Key Laboratory of Carcinogenesis, Ministry of Health, Changsha 410078, China
| | - Ya Cao
- Cancer Research Institute, Central South University, Changsha 410078, China Key Laboratory of Carcinogenesis and Cancer Invasion, Ministry of Education, Changsha 410078, China Key Laboratory of Carcinogenesis, Ministry of Health, Changsha 410078, China
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Tian W, Li W, Chen Y, Yan Z, Huang X, Zhuang H, Zhong W, Chen Y, Wu W, Lin C, Chen H, Hou X, Zhang L, Sui S, Zhao B, Hu Z, Li L, Feng D. Phosphorylation of ULK1 by AMPK regulates translocation of ULK1 to mitochondria and mitophagy. FEBS Lett 2015; 589:1847-54. [PMID: 25980607 DOI: 10.1016/j.febslet.2015.05.020] [Citation(s) in RCA: 133] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2015] [Revised: 04/29/2015] [Accepted: 05/08/2015] [Indexed: 01/09/2023]
Abstract
UNC-51 like kinase (ULK1) translocates to dysfunctional mitochondria and is involved in mitophagy, but the mechanisms responsible for ULK1 activation and translocation remain unclear. Here, we found that hypoxia induces phosphorylation of ULK1 at Serine-555 by Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK). Unlike wild-type ULK1, an ULK1 (S555A) mutant cannot translocate to mitochondria in response to hypoxia. Inhibition or knockdown of AMPK prevents ULK1 translocation and inhibits mitophagy. Finally, the phospho-mimic ULK1 (S555D) mutant, but not ULK1 (S555A), rescues mitophagy in AMPK-knockdown cells. Thus, we conclude that AMPK-dependent phosphorylation of ULK1 is critical for translocation of ULK1 to mitochondria and for mitophagy in response to hypoxic stress.
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Affiliation(s)
- Weili Tian
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Wen Li
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Yinqin Chen
- Department of Vascular Surgery, Thyroid and Mammary Gland Surgery, Guangdong Medical College, Zhanjiang 524001, China
| | - Zeming Yan
- Department of Interventional Radiology, Guangdong Medical College, Zhanjiang 524001, China
| | - Xia Huang
- Department of Anesthesiology, Guangdong Medical College, Zhanjiang 524001, China
| | - Haixia Zhuang
- Department of Anesthesiology, Guangdong Medical College, Zhanjiang 524001, China
| | - Wangtao Zhong
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Yusen Chen
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Wenxian Wu
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Chunxia Lin
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Hao Chen
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Xiaoyan Hou
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Liangqing Zhang
- Department of Anesthesiology, Guangdong Medical College, Zhanjiang 524001, China
| | - Senfang Sui
- State Key Laboratory of Biomembrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China
| | - Bin Zhao
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China
| | - Zhe Hu
- Department of Anesthesiology, Guangdong Medical College, Zhanjiang 524001, China.
| | - Longxuan Li
- Department of Neurology, Gongli Hospital, Pudong New Area, Shanghai 200135, China.
| | - Du Feng
- Guangdong Key Laboratory of Age-related Cardiac-cerebral Vascular Disease, Institute of Neurology, Affiliated Hospital of Guangdong Medical College, Guangdong Medical College, Zhanjiang 524001, Guangdong, China.
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