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Soltani S, Webb SM, Kroll T, King-Jones K. Drosophila Evi5 is a critical regulator of intracellular iron transport via transferrin and ferritin interactions. Nat Commun 2024; 15:4045. [PMID: 38744835 PMCID: PMC11094094 DOI: 10.1038/s41467-024-48165-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Accepted: 04/22/2024] [Indexed: 05/16/2024] Open
Abstract
Vesicular transport is essential for delivering cargo to intracellular destinations. Evi5 is a Rab11-GTPase-activating protein involved in endosome recycling. In humans, Evi5 is a high-risk locus for multiple sclerosis, a debilitating disease that also presents with excess iron in the CNS. In insects, the prothoracic gland (PG) requires entry of extracellular iron to synthesize steroidogenic enzyme cofactors. The mechanism of peripheral iron uptake in insect cells remains controversial. We show that Evi5-depletion in the Drosophila PG affected vesicle morphology and density, blocked endosome recycling and impaired trafficking of transferrin-1, thus disrupting heme synthesis due to reduced cellular iron concentrations. We show that ferritin delivers iron to the PG as well, and interacts physically with Evi5. Further, ferritin-injection rescued developmental delays associated with Evi5-depletion. To summarize, our findings show that Evi5 is critical for intracellular iron trafficking via transferrin-1 and ferritin, and implicate altered iron homeostasis in the etiology of multiple sclerosis.
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Affiliation(s)
- Sattar Soltani
- University of Alberta, Faculty of Science, Edmonton, Alberta, T6G 2E9, Canada
| | - Samuel M Webb
- Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Thomas Kroll
- Stanford Synchrotron Radiation Lightsource SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - Kirst King-Jones
- University of Alberta, Faculty of Science, Edmonton, Alberta, T6G 2E9, Canada.
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2
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Alkafaas SS, Loutfy SA, Diab T, Hessien M. Vasopressin induces apoptosis but does not enhance the antiproliferative effect of dynamin 2 or PI3K/Akt inhibition in luminal A breast cancer cells. Med Oncol 2023; 40:35. [PMID: 36460880 PMCID: PMC9718716 DOI: 10.1007/s12032-022-01889-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 11/08/2022] [Indexed: 12/04/2022]
Abstract
Breast cancer cells abnormally express vasopressin (AVP) and its receptors. The effect of AVP is largely orchestrated through its downstream signaling and by receptor-mediated endocytosis (RME), in which Dynamin 2 (Dyn2) plays an integral role in vesicle closure. In this work, luminal A breast cancer cells were treated with AVP, and then Dynasore (DYN) was employed to inhibit Dyn2 to explore the combined effect of AVP and Dyn2 inhibition on the survival of breast cancer cells. The results revealed that DYN alone demonstrated a concentration-dependent cytotoxic effect in AVP untreated cells. Apoptosis developed in 29.7 and 30.3% of cells treated with AVP or AVP+DYN, respectively, compared to 32.5% in cells treated with Wortmannin (Wort, a selective PI3K pathway inhibitor). More apoptosis was observed when cells were treated with DYN+Wort in presence or absence of exogenous AVP. Besides, 2 or 4- fold increases in the expression of Bax and Caspase-3, were observed in cells exposed to AVP in absence or presence of DYN, respectively. This was associated with higher levels of the autophagy marker (LC3II protein). Meanwhile, the activation of Akt protein, sequentially decreased in the same pattern. Cell's invasion decreased when they were exposed to AVP alone or combined with DYN or/and Wort. Conclusively, although many reports suggested the proliferative effect of AVP, the results predict the antiproliferative and antimetastatic effects of 100 nM AVP in luminal A breast cancer cells. However, the hormone did not enhance the cytotoxic effect of Dyn 2 or PI3K pathway inhibition. Summary of the Dynamin 2 independent AVP antiproliferative effects. Breast cancer cells expresses AVP as a Prohormone (A). At high dose of AVP, the hormone is liganded with AVP receptor (B) to initiate RME, where the endosomed complex (C) is degraded through the endosome-lysosome system, as a part of signal management. These events consume soluble Dyn2 in neck closure and vesicle fission (D). This makes the cells more substitutable to the direct apoptotic effect of DYN (E). Alternatively, at lower AVP doses the liganded AVP may initiate cAMP-mediated downstream signaling (F) and cellular proliferation. In parallel, Wort inhibits PIP2-PIP3 conversion (G) and the subsequent inhibition of PI3K/Akt/mTOR pathway leading to cell death.
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Affiliation(s)
- Samar Sami Alkafaas
- grid.412258.80000 0000 9477 7793Molecular Cell Biology Unit, Division of Biochemistry, Department of Chemistry, Faculty of Science, Tanta University, Tanta, 31511 Egypt
| | - Samah A. Loutfy
- grid.7776.10000 0004 0639 9286Virology and Immunology Unit, Cancer Biology Department, National Cancer Institute, Cairo University, Cairo, Egypt ,grid.440862.c0000 0004 0377 5514Nanotechnology Research Center, British University, Cairo, Egypt
| | - Thoria Diab
- grid.412258.80000 0000 9477 7793Division of Biochemistry, Department of Chemistry, Faculty of Science, Tanta University, Tanta, 31511 Egypt
| | - Mohamed Hessien
- grid.412258.80000 0000 9477 7793Molecular Cell Biology Unit, Division of Biochemistry, Department of Chemistry, Faculty of Science, Tanta University, Tanta, 31511 Egypt
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3
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Xu L, Qiu Y, Wang X, Shang W, Bai J, Shi K, Liu H, Liu JP, Wang L, Tong C. ER-mitochondrial contact protein Miga regulates autophagy through Atg14 and Uvrag. Cell Rep 2022; 41:111583. [DOI: 10.1016/j.celrep.2022.111583] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2021] [Revised: 08/10/2022] [Accepted: 10/07/2022] [Indexed: 11/06/2022] Open
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4
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Saffi GT, Tang E, Mamand S, Inpanathan S, Fountain A, Salmena L, Botelho RJ. Reactive oxygen species prevent lysosome coalescence during PIKfyve inhibition. PLoS One 2021; 16:e0259313. [PMID: 34813622 PMCID: PMC8610251 DOI: 10.1371/journal.pone.0259313] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/16/2021] [Indexed: 11/19/2022] Open
Abstract
Lysosomes are terminal, degradative organelles of the endosomal pathway that undergo repeated fusion-fission cycles with themselves, endosomes, phagosomes, and autophagosomes. Lysosome number and size depends on balanced fusion and fission rates. Thus, conditions that favour fusion over fission can reduce lysosome numbers while enlarging their size. Conversely, favouring fission over fusion may cause lysosome fragmentation and increase their numbers. PIKfyve is a phosphoinositide kinase that generates phosphatidylinositol-3,5-bisphosphate to modulate lysosomal functions. PIKfyve inhibition causes an increase in lysosome size and reduction in lysosome number, consistent with lysosome coalescence. This is thought to proceed through reduced lysosome reformation and/or fission after fusion with endosomes or other lysosomes. Previously, we observed that photo-damage during live-cell imaging prevented lysosome coalescence during PIKfyve inhibition. Thus, we postulated that lysosome fusion and/or fission dynamics are affected by reactive oxygen species (ROS). Here, we show that ROS generated by various independent mechanisms all impaired lysosome coalescence during PIKfyve inhibition and promoted lysosome fragmentation during PIKfyve re-activation. However, depending on the ROS species or mode of production, lysosome dynamics were affected distinctly. H2O2 impaired lysosome motility and reduced lysosome fusion with phagosomes, suggesting that H2O2 reduces lysosome fusogenecity. In comparison, inhibitors of oxidative phosphorylation, thiol groups, glutathione, or thioredoxin, did not impair lysosome motility but instead promoted clearance of actin puncta on lysosomes formed during PIKfyve inhibition. Additionally, actin depolymerizing agents prevented lysosome coalescence during PIKfyve inhibition. Thus, we discovered that ROS can generally prevent lysosome coalescence during PIKfyve inhibition using distinct mechanisms depending on the type of ROS.
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Affiliation(s)
- Golam T. Saffi
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
| | - Evan Tang
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Sami Mamand
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Polytechnic Research Center, Erbil Polytechnic University, Kurdistan Regional Government, Erbil, Kurdistan
| | - Subothan Inpanathan
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Aaron Fountain
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
| | - Leonardo Salmena
- Department of Pharmacology & Toxicology, University of Toronto, Toronto, Ontario, Canada
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Roberto J. Botelho
- Molecular Science Graduate Program, Ryerson University, Toronto, Ontario, Canada
- Department of Chemistry and Biology, Ryerson University, Toronto, Ontario, Canada
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5
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Gospocic J, Glastad KM, Sheng L, Shields EJ, Berger SL, Bonasio R. Kr-h1 maintains distinct caste-specific neurotranscriptomes in response to socially regulated hormones. Cell 2021; 184:5807-5823.e14. [PMID: 34739833 DOI: 10.1016/j.cell.2021.10.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Revised: 07/13/2021] [Accepted: 10/07/2021] [Indexed: 10/19/2022]
Abstract
Behavioral plasticity is key to animal survival. Harpegnathos saltator ants can switch between worker and queen-like status (gamergate) depending on the outcome of social conflicts, providing an opportunity to study how distinct behavioral states are achieved in adult brains. Using social and molecular manipulations in live ants and ant neuronal cultures, we show that ecdysone and juvenile hormone drive molecular and functional differences in the brains of workers and gamergates and direct the transcriptional repressor Kr-h1 to different target genes. Depletion of Kr-h1 in the brain caused de-repression of "socially inappropriate" genes: gamergate genes were upregulated in workers, whereas worker genes were upregulated in gamergates. At the phenotypic level, loss of Kr-h1 resulted in the emergence of worker-specific behaviors in gamergates and gamergate-specific traits in workers. We conclude that Kr-h1 is a transcription factor that maintains distinct brain states established in response to socially regulated hormones.
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Affiliation(s)
- Janko Gospocic
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Urology and Institute of Neuropathology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Karl M Glastad
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Lihong Sheng
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA
| | - Emily J Shields
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Urology and Institute of Neuropathology, Medical Center-University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg, Germany
| | - Shelley L Berger
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA; Department of Biology, University of Pennsylvania School of Arts and Sciences, Philadelphia, PA 19104, USA.
| | - Roberto Bonasio
- Epigenetics Institute and Department of Cell and Developmental Biology, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA 19104, USA.
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6
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Duan X, Tong C. Autophagy in Drosophila and Zebrafish. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2021; 1208:333-356. [PMID: 34260032 DOI: 10.1007/978-981-16-2830-6_15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Autophagy is a highly conserved cellular process that delivers cellular contents to the lysosome for degradation. It not only serves as a bulk degradation system for various cytoplasmic components but also functions selectively to clear damaged organelles, aggregated proteins, and invading pathogens (Feng et al., Cell Res 24:24-41, 2014; Galluzzi et al., EMBO J 36:1811-36, 2017; Klionsky et al., Autophagy 12:1-222, 2016). The malfunction of autophagy leads to multiple developmental defects and diseases (Mizushima et al., Nature 451:1069-75, 2008). Drosophila and zebrafish are higher metazoan model systems with sophisticated genetic tools readily available, which make it possible to dissect the autophagic processes and to understand the physiological functions of autophagy (Lorincz et al., Cells 6:22, 2017a; Mathai et al., Cells 6:21, 2017; Zhang and Baehrecke, Trends Cell Biol 25:376-87, 2015). In this chapter, we will discuss recent progress that has been made in the autophagic field by using these animal models. We will focus on the protein machineries required for autophagosome formation and maturation as well as the physiological roles of autophagy in both Drosophila and zebrafish.
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Affiliation(s)
- Xiuying Duan
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chao Tong
- MOE Key Laboratory for Biosystems Homeostasis and Protection and Innovation Center for Cell Signaling Network, Life Sciences Institute, Zhejiang University, Hangzhou, Zhejiang, China. .,The Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
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7
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Xiao Q, Hu Y, Yang X, Tang J, Wang X, Xue X, Li M, Wang M, Zhao Y, Liu J, Wang H. Changes in Protein Phosphorylation during Salivary Gland Degeneration in Haemaphysalis longicornis. THE KOREAN JOURNAL OF PARASITOLOGY 2020; 58:161-171. [PMID: 32418385 PMCID: PMC7231830 DOI: 10.3347/kjp.2020.58.2.161] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Accepted: 03/10/2020] [Indexed: 01/19/2023]
Abstract
The ticks feed large amount of blood from their hosts and transmit pathogens to the victims. The salivary gland plays an important role in the blood feeding. When the female ticks are near engorgement, the salivary gland gradually loses its functions and begins to rapidly degenerate. In this study, data-independent acquisition quantitative proteomics was used to study changes in the phosphorylation modification of proteins during salivary gland degeneration in Haemaphysalis longicornis. In this quantitative study, 400 phosphorylated proteins and 850 phosphorylation modification sites were identified. Trough RNA interference experiments, we found that among the proteins with changes in phosphorylation, apoptosis-promoting Hippo protein played a role in salivary gland degeneration.
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Affiliation(s)
- Qi Xiao
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Yuhong Hu
- Instrumental Analysis Center, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaohong Yang
- Department of Pathogenic Biology, College of Basic Medicine, Hebei Medical University, Shijiazhuang, Hebei 050017, PR China.,State Key Laboratory of Veterinary Etiological Biology, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu 730046, PR China
| | - Jianna Tang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaoshuang Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Xiaomin Xue
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Mengxue Li
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Minjing Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Yinan Zhao
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Jingze Liu
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
| | - Hui Wang
- Hebei Key Laboratory of Animal Physiology, Biochemistry and Molecular Biology, College of Life Sciences, Hebei Normal University, Shijiazhuang, Hebei 050024, PR China
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8
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Cao H, Krueger EW, Chen J, Drizyte-Miller K, Schulz ME, McNiven MA. The anti-viral dynamin family member MxB participates in mitochondrial integrity. Nat Commun 2020; 11:1048. [PMID: 32102993 PMCID: PMC7044337 DOI: 10.1038/s41467-020-14727-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 01/23/2020] [Indexed: 12/19/2022] Open
Abstract
The membrane deforming dynamin family members MxA and MxB are large GTPases that convey resistance to a variety of infectious viruses. During viral infection, Mx proteins are known to show markedly increased expression via an interferon-responsive promoter to associate with nuclear pores. In this study we report that MxB is an inner mitochondrial membrane GTPase that plays an important role in the morphology and function of this organelle. Expression of mutant MxB or siRNA knockdown of MxB leads to fragmented mitochondria with disrupted inner membranes that are unable to maintain a proton gradient, while expelling their nucleoid-based genome into the cytoplasm. These findings implicate a dynamin family member in mitochondrial-based changes frequently observed during an interferon-based, anti-viral response. Mx proteins belong to the dynamin family of large GTPases and are highly induced by interferon in virally infected cells. The authors show that uninfected immune cells and hepatocytes also express MxB protein that associates with mitochondria to alter the morphology and genome of this organelle.
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Affiliation(s)
- Hong Cao
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA.,Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - E W Krueger
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - Jing Chen
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - Kristina Drizyte-Miller
- Biochemistry and Molecular Biology Program, Mayo Clinic Graduate School of Biomedical Sciences, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - Mary E Schulz
- Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA
| | - Mark A McNiven
- Department of Biochemistry and Molecular Biology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA. .,Center for Basic Research in Digestive Diseases, Division of Gastroenterology & Hepatology, Mayo Clinic, 200 1st Street SW, Rochester, MN, 55905, USA.
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9
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Zatyka M, Sarkar S, Barrett T. Autophagy in Rare (NonLysosomal) Neurodegenerative Diseases. J Mol Biol 2020; 432:2735-2753. [PMID: 32087199 PMCID: PMC7232014 DOI: 10.1016/j.jmb.2020.02.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Revised: 02/10/2020] [Accepted: 02/10/2020] [Indexed: 12/13/2022]
Abstract
Neurodegenerative diseases (NDDs) comprise conditions with impaired neuronal function and loss and may be associated with a build-up of aggregated proteins with altered physicochemical properties (misfolded proteins). There are many disorders, and causes include gene mutations, infections, or exposure to toxins. The autophagy pathway is involved in the removal of unwanted proteins and organelles through lysosomes. While lysosomal storage disorders have been described for many years, it is now recognised that perturbations of the autophagy pathway itself can also lead to neurodegenerative disease. These include monogenic disorders of key proteins involved in the autophagy pathway, and disorders within pathways that critically control autophagy through monitoring of the supply of nutrients (mTORC1 pathway) or of energy supply in cells (AMPK pathway). This review focuses on childhood-onset neurodegenerative disorders with perturbed autophagy, due to defects in the autophagy pathway, or in upstream signalling via mTORC1 and AMPK. The review first provides a short description of autophagy, as related to neurons. It then examines the extended role of autophagy in neuronal function, plasticity, and memory. There follows a description of each step of the autophagy pathway in greater detail, illustrated with examples of diseases grouped by the stage of their perturbation of the pathway. Each disease is accompanied by a short clinical description, to illustrate the diversity but also the overlap of symptoms caused by perturbation of key proteins necessary for the proper functioning of autophagy. Finally, there is a consideration of current challenges that need addressing for future therapeutic advances. Autophagy is an important pathway for the removal of misfolded proteins from terminally differentiated neurons. Monogenic defects in autophagy cause childhood-onset neurodegeneration. Defects in different stages of the pathway may present with overlapping clinical features. Increasing autophagic flux may be a therapeutic strategy to treat many autophagic disorders.
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Affiliation(s)
- Malgorzata Zatyka
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Sovan Sarkar
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK
| | - Timothy Barrett
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham, B15 2TT, UK; Department of Endocrinology, Birmingham Women's and Children's Hospital, Steelhouse Lane, Birmingham B4 6NH, UK.
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10
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Graves HK, Jangam S, Tan KL, Pignata A, Seto ES, Yamamoto S, Wangler MF. A Genetic Screen for Genes That Impact Peroxisomes in Drosophila Identifies Candidate Genes for Human Disease. G3 (BETHESDA, MD.) 2020; 10:69-77. [PMID: 31767637 PMCID: PMC6945042 DOI: 10.1534/g3.119.400803] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 11/11/2019] [Indexed: 02/06/2023]
Abstract
Peroxisomes are subcellular organelles that are essential for proper function of eukaryotic cells. In addition to being the sites of a variety of oxidative reactions, they are crucial regulators of lipid metabolism. Peroxisome loss or dysfunction leads to multi-system diseases in humans that strongly affect the nervous system. In order to identify previously unidentified genes and mechanisms that impact peroxisomes, we conducted a genetic screen on a collection of lethal mutations on the X chromosome in Drosophila Using the number, size and morphology of GFP tagged peroxisomes as a readout, we screened for mutations that altered peroxisomes based on clonal analysis and confocal microscopy. From this screen, we identified eighteen genes that cause increases in peroxisome number or altered morphology when mutated. We examined the human homologs of these genes and found that they are involved in a diverse array of cellular processes. Interestingly, the human homologs from the X-chromosome collection are under selective constraint in human populations and are good candidate genes particularly for dominant genetic disease. This in vivo screening approach for peroxisome defects allows identification of novel genes that impact peroxisomes in vivo in a multicellular organism and is a valuable platform to discover genes potentially involved in dominant disease that could affect peroxisomes.
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Affiliation(s)
| | | | - Kai Li Tan
- Department of Molecular and Human Genetics
| | | | | | - Shinya Yamamoto
- Department of Molecular and Human Genetics,
- Department of Neuroscience
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, and
- Jan and Dan Duncan Neurological Research Institute, Texas Children Hospital, Houston, TX 77030
| | - Michael F Wangler
- Department of Molecular and Human Genetics,
- Program in Developmental Biology, Baylor College of Medicine, Houston, TX 77030, and
- Jan and Dan Duncan Neurological Research Institute, Texas Children Hospital, Houston, TX 77030
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11
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Calcium Dyshomeostasis and Lysosomal Ca 2+ Dysfunction in Amyotrophic Lateral Sclerosis. Cells 2019; 8:cells8101216. [PMID: 31597311 PMCID: PMC6829585 DOI: 10.3390/cells8101216] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2019] [Revised: 09/24/2019] [Accepted: 10/03/2019] [Indexed: 12/11/2022] Open
Abstract
Recent findings in the understanding of amyotrophic lateral sclerosis (ALS) revealed that alteration in calcium (Ca2+) homeostasis may largely contribute to motor neuron demise. A large part of these alterations is due to dysfunctional Ca2+-storing organelles, including the endoplasmic reticulum (ER) and mitochondria. Very recently, lysosomal Ca2+ dysfunction has emerged as an important pathological change leading to neuronal loss in ALS. Remarkably, the Ca2+-storing organelles are interacting with each other at specialized domains controlling mitochondrial dynamics, ER/lysosomal function, and autophagy. This occurs as a result of interaction between specific ionic channels and Ca2+-dependent proteins located in each structure. Therefore, the dysregulation of these ionic mechanisms could be considered as a key element in the neurodegenerative process. This review will focus on the possible role of lysosomal Ca2+ dysfunction in the pathogenesis of several neurodegenerative diseases, including ALS and shed light on the possibility that specific lysosomal Ca2+ channels might represent new promising targets for preventing or at least delaying neurodegeneration in ALS.
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12
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Mezzofanti E, Ignesti M, Hsu T, Gargiulo G, Cavaliere V. Vps28 Is Involved in the Intracellular Trafficking of Awd, the Drosophila Homolog of NME1/2. Front Physiol 2019; 10:983. [PMID: 31427986 PMCID: PMC6687847 DOI: 10.3389/fphys.2019.00983] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Accepted: 07/15/2019] [Indexed: 12/12/2022] Open
Abstract
The Awd (abnormal wing discs) gene is the Drosophila homolog of human NME1 and NME2 metastasis suppressor genes. These genes play a key role in tumor progression. Extensive studies revealed that intracellular NME1/2 protein levels could be related to either favorable or poor prognosis depending on tissue context. More recently, extracellular activities of NME1/2 proteins have also been reported, including a tumor- promoting function. We used Drosophila as a genetic model to investigate the mechanism controlling intra- and extracellular levels of NME1/2. We examined the role of several components of the ESCRT (endosomal sorting complex required for transport) complex in controlling Awd trafficking. We show that the Vps28 component of the ESCRT-I complex is required for maintenance of normal intracellular level of Awd in larval adipocytes. We already showed that blocking of Shibire (Shi)/Dynamin function strongly- lowers Awd intracellular level. To further investigate this down regulative effect, we analyzed the distribution of endosomal markers in wild type and Shi-defective adipocytes. Our results suggest that Awd does not enter CD63-positive endosomes. Interestingly, we found that in fat body cells, Awd partly- colocalizes with the ESCRT accessory component ALiX, the ALG-2 (apoptosis-linked gene 2)-interacting protein X. Moreover, we show that the intracellular levels of both proteins are downregulated by blocking the function of the Dynamin encoded by the shibire gene.
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Affiliation(s)
- Elisa Mezzofanti
- Dipartimento di Farmacia e Biotecnologie, Alma Mater Studiorum - Università di Bologna, Bologna, Italy
| | - Marilena Ignesti
- Dipartimento di Farmacia e Biotecnologie, Alma Mater Studiorum - Università di Bologna, Bologna, Italy
| | - Tien Hsu
- Department of Biomedical Sciences and Engineering, National Central University, Zhongli, Taiwan.,Center for Chronic Disease Management and Research, National Central University, Zhongli, Taiwan
| | - Giuseppe Gargiulo
- Dipartimento di Farmacia e Biotecnologie, Alma Mater Studiorum - Università di Bologna, Bologna, Italy
| | - Valeria Cavaliere
- Dipartimento di Farmacia e Biotecnologie, Alma Mater Studiorum - Università di Bologna, Bologna, Italy
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13
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Zhu Y, Runwal G, Obrocki P, Rubinsztein DC. Autophagy in childhood neurological disorders. Dev Med Child Neurol 2019; 61:639-645. [PMID: 30417343 DOI: 10.1111/dmcn.14092] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/21/2018] [Indexed: 01/16/2023]
Abstract
Autophagy is a tightly modulated lysosomal degradation pathway. Genetic disorders of autophagy during nervous system development may lead to developmental delay, neurodegeneration, and other neurological signs in children. Here we aimed to summarize single gene disorders that perturb various steps of autophagy pathway and their roles in the causation of childhood neurological diseases. Numerous childhood-onset disorders are caused by mutations that impact the autophagy pathway. These can manifest with a range of features including ataxia, spastic paraplegia, and intellectual disability. Defective proteins causing such diseases can interfere with autophagy flux at different stages of the itinerary. Defective autophagy may be an important contributor to the pathological features of various childhood neurodegenerative diseases and lead to the accumulation of aberrant protein and dysfunctional organelles. Insights into the relevant cell biological processes may help understand pathophysiological mechanisms and inspire autophagy-restoring therapeutic approaches. WHAT THIS PAPER ADDS: Numerous childhood-onset disorders are caused by mutations that impact the autophagy pathway. Defective autophagy is a feature of some mutations that cause ataxia, spastic paraplegia, and intellectual disability.
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Affiliation(s)
- Ye Zhu
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK
| | - Gautam Runwal
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK
| | - Pawel Obrocki
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge, UK.,UK Dementia Research Institute, Wellcome Trust, Cambridge Biomedical Campus, Cambridge, UK
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14
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Chen X, Miller NM, Afghah Z, Geiger JD. Development of AD-Like Pathology in Skeletal Muscle. JOURNAL OF PARKINSON'S DISEASE AND ALZHEIMER'S DISEASE 2019; 6:10.13188/2376-922x.1000028. [PMID: 32190732 PMCID: PMC7079679 DOI: 10.13188/2376-922x.1000028] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Effective therapeutic strategy against Alzheimer's disease (AD) requires early detection of AD; however, clinical diagnosis of Alzheimer's disease (AD) is not precise and a definitive diagnosis of AD is only possible via postmortem examination for AD pathological hallmarks including senile plaques composed of Aβ and neuro fibrillary tangles composed of phosphorylated tau. Although a variety of biomarker has been developed and used in clinical setting, none of them robustly predicts subsequent clinical course of AD. Thus, it is essential to identify new biomarkers that may facilitate the diagnosis of early stages of AD, prediction of subsequent clinical course, and development of new therapeutic strategies. Given that pathological hallmarks of AD including Aβaccumulation and the presence of phosphorylated tau are also detected in peripheral tissues, AD is considered a systemic disease. Without the protection of blood-brain barrier, systemic factors can affect peripheral tissues much earlier than neurons in brain. Here, we will discuss the development of AD-like pathology in skeletal muscle and the potential use of skeletal muscle biopsy (examination for Aβaccumulation and phosphorylated tau) as a biomarker for AD.
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Affiliation(s)
- X Chen
- Department of Biomedical Sciences, University of North Dakota, USA
| | - NM Miller
- Department of Biomedical Sciences, University of North Dakota, USA
| | - Z Afghah
- Department of Biomedical Sciences, University of North Dakota, USA
| | - JD Geiger
- Department of Biomedical Sciences, University of North Dakota, USA
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15
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Liu W, Duan X, Fang X, Shang W, Tong C. Mitochondrial protein import regulates cytosolic protein homeostasis and neuronal integrity. Autophagy 2018; 14:1293-1309. [PMID: 29909722 DOI: 10.1080/15548627.2018.1474991] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Neurodegeneration is characterized by protein aggregate deposits and mitochondrial malfunction. Reduction in Tom40 (translocase of outer membrane 40) expression, a key subunit of the translocase of the outer mitochondrial membrane complex, led to accumulation of ubiquitin (Ub)-positive protein aggregates engulfed by Atg8a-positive membranes. Other macroautophagy markers were also abnormally accumulated. Autophagy was induced but the majority of autophagosomes failed to fuse with lysosomes when Tom40 was downregulated. In Tom40 RNAi tissues, autophagosome-like (AL) structures, often not sealed, were 10 times larger than starvation induced autophagosomes. Atg5 downregulation abolished Tom40 RNAi induced AL structure formation, but the Ub-positive aggregates remained, whereas knock down of Syx17, a gene required for autophagosome-lysosome fusion, led to the disappearance of giant AL structures and accumulation of small autophagosomes and phagophores near the Ub-positive aggregates. The protein aggregates contained many mitochondrial preproteins, cytosolic proteins, and proteasome subunits. Proteasome activity and ATP levels were reduced and the ROS levels was increased in Tom40 RNAi tissues. The simultaneous inhibition of proteasome activity, reduction in ATP production, and increase in ROS, but none of these conditions alone, can mimic the imbalanced proteostasis phenotypes observed in Tom40 RNAi cells. Knockdown of ref(2)P or ectopic expression of Pink1 and park greatly reduced aggregate formation in Tom40 RNAi tissues. In nerve tissues, reduction in Tom40 activity leads to aggregate formation and neurodegeneration. Rather than diminishing the neurodegenerative phenotypes, overexpression of Pink1 enhanced them. We proposed that defects in mitochondrial protein import may be the key to linking imbalanced proteostasis and mitochondrial defects. ABBREVIATIONS AL: autophagosome-like; Atg12: Autophagy-related 12; Atg14: Autophagy-related 14; Atg16: Autophagy-related 16; Atg5: Autophagy-related 5; Atg6: Autophagy-related 6; Atg8a: Autophagy-related 8a; Atg9: Autophagy-related 9; ATP: adenosine triphosphate; Cas9: CRISPR associated protein 9; cDNA: complementary DNA; COX4: Cytochrome c oxidase subunit 4; CRISPR: clustered regularly interspaced short palindromic repeats; Cyt-c1: Cytochrome c1; DAPI: 4,6-diamidino-2-phenylindole dihydrochloride; Dcr-2: Dicer-2; FLP: Flippase recombination enzyme; FRT: FLP recombination target; GFP: green fluorescent protein; GO: gene ontology; gRNA: guide RNA; Hsp60: Heat shock protein 60A; HDAC6: Histone deacetylase 6; htt: huntingtin; Idh: Isocitrate dehydrogenase; IFA: immunofluorescence assay; Irp-1A: Iron regulatory protein 1A; kdn: knockdown; Marf: Mitochondrial assembly regulatory factor; MitoGFP: Mitochondrial-GFP; MS: mass spectrometry; MTPAP: mitochondrial poly(A) polymerase; Nmnat: Nicotinamide mononucleotide adenylyltransferase; OE: overexpression; Pink1/PINK1: PTEN-induced putative kinase 1; polyQ: polyglutamine; PRKN: parkin RBR E3 ubiquitin protein ligase; Prosα4: proteasome α4 subunit; Prosβ1: proteasome β1 subunit; Prosβ5: proteasome β5 subunit; Prosβ7: proteasome β7 subunit; ref(2)P: refractory to sigma P; RFP: red fluorescent protein; RNAi: RNA interference; ROS: reactive oxygen species; Rpn11: Regulatory particle non-ATPase 11; Rpt2: Regulatory particle triple-A ATPase 2; scu: scully; sicily: severe impairment of CI with lengthened youth; sesB: stress-sensitive B; Syx17: Syntaxin17; TEM: transmission electron microscopy; ttm50: tiny tim 50; Tom: translocase of the outer membrane; Tom20: translocase of outer membrane 20; Tom40: translocase of outer membrane 40; Tom70: translocase of outer membrane 70; UAS: upstream active sequence; Ub: ubiquitin; VNC: ventral nerve cord; ZFYVE1: zinc finger FYVE-type containing 1.
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Affiliation(s)
- Wei Liu
- a Life Sciences Institute and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , China
| | - Xiuying Duan
- a Life Sciences Institute and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , China
| | - Xuefei Fang
- a Life Sciences Institute and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , China
| | - Weina Shang
- a Life Sciences Institute and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , China
| | - Chao Tong
- a Life Sciences Institute and Innovation Center for Cell Signaling Network , Zhejiang University , Hangzhou , China
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16
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Congdon EE. Sex Differences in Autophagy Contribute to Female Vulnerability in Alzheimer's Disease. Front Neurosci 2018; 12:372. [PMID: 29988365 PMCID: PMC6023994 DOI: 10.3389/fnins.2018.00372] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 05/14/2018] [Indexed: 12/11/2022] Open
Abstract
Alzheimer's disease (AD) is the most common form of dementia, with over 5. 4 million cases in the US alone (Alzheimer's Association, 2016). Clinically, AD is defined by the presence of plaques composed of Aβ and neurofibrillary pathology composed of the microtubule associated protein tau. Another key feature is the dysregulation of autophagy at key steps in the pathway. In AD, disrupted autophagy contributes to disease progression through the failure to clear pathological protein aggregates, insulin resistance, and its role in the synthesis of Aβ. Like many psychiatric and neurodegenerative diseases, the risk of developing AD, and disease course are dependent on the sex of the patient. One potential mechanism through which these differences occur, is the effects of sex hormones on autophagy. In women, the loss of hormones with menopause presents both a risk factor for developing AD, and an obvious example of where sex differences in AD can stem from. However, because AD pathology can begin decades before menopause, this does not provide the full answer. We propose that sex-based differences in autophagy regulation during the lifespan contribute to the increased risk of AD, and greater severity of pathology seen in women.
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Affiliation(s)
- Erin E Congdon
- Neuroscience and Physiology, School of Medicine, New York University, New York City, NY, United States
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17
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Persaud A, Cormerais Y, Pouyssegur J, Rotin D. Dynamin inhibitors block activation of mTORC1 by amino acids independently of dynamin. J Cell Sci 2018; 131:jcs.211755. [PMID: 29150487 DOI: 10.1242/jcs.211755] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 11/08/2017] [Indexed: 02/04/2023] Open
Abstract
mTORC1 plays a crucial role in protein synthesis and cell proliferation and growth. It is activated by growth factors and amino acids, including essential amino acids (EAAs), such as leucine; Leu enters cells via the Leu transporter LAT1-4F2hc (also known as SLC7A5-SLC3A2) and potentially via endocytosis. Here, we investigated the contribution of the different routes of Leu entry into cells to mTORC1 activation using pharmacological inhibitors and cells that lack LAT1 or dynamin-1, -2 and -3. Our results show that LAT1 is the major route of Leu entry into cells and mTORC1 activation (∼70%), whereas dynamin-dependent endocytosis and macropinocytosis contribute minimally to both (5-15%). However, macropinocytosis contributes significantly (∼40%) to activation of mTORC1 by other EAAs. Surprisingly, the dynamin inhibitors dynasore and Dyngo 4A, which minimally inhibited Leu uptake, abolished mTORC1 activation independently of dynamin. Instead, dynasore inhibited RagA binding to Raptor, reduced mTORC1 recruitment to the lysosome, and inhibited Akt activation and TSC2-S939 phosphorylation; this resulted in inhibition of Rheb and mTORC1 activity. Our results suggest that these commonly used inhibitors of dynamin and endocytosis are potent suppressors of mTORC1 activation via off-target effects and not via dynamin inhibition.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Avinash Persaud
- Program in Cell Biology, The Hospital for Sick Children, and Biochemistry Department, University of Toronto, Toronto, Ontario, Canada, M5G 0A4
| | - Yann Cormerais
- Medical Biology Department, Centre Scientifique de Monaco (CSM), 98000 Monaco
| | - Jacques Pouyssegur
- Medical Biology Department, Centre Scientifique de Monaco (CSM), 98000 Monaco.,Université Côte d'Azur, IRCAN, CNRS, Inserm, Centre A Lacassagne, Nice 06189, France
| | - Daniela Rotin
- Program in Cell Biology, The Hospital for Sick Children, and Biochemistry Department, University of Toronto, Toronto, Ontario, Canada, M5G 0A4
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18
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Batoko H, Dagdas Y, Baluska F, Sirko A. Understanding and exploiting autophagy signaling in plants. Essays Biochem 2017; 61:675-685. [PMID: 29233877 PMCID: PMC5869243 DOI: 10.1042/ebc20170034] [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: 08/31/2017] [Revised: 10/11/2017] [Accepted: 10/19/2017] [Indexed: 12/20/2022]
Abstract
Autophagy is an essential catabolic pathway and is activated by various endogenous and exogenous stimuli. In particular, autophagy is required to allow sessile organisms such as plants to cope with biotic or abiotic stress conditions. It is thought that these various environmental signaling pathways are somehow integrated with autophagy signaling. However, the molecular mechanisms of plant autophagy signaling are not well understood, leaving a big gap of knowledge as a barrier to being able to manipulate this important pathway to improve plant growth and development. In this review, we discuss possible regulatory mechanisms at the core of plant autophagy signaling.
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Affiliation(s)
- Henri Batoko
- Université catholique de Louvain, Institut des Sciences de la Vie, Croix du Sud 4, L7.07.14, 1348 Louvain-la-Neuve, Belgium
| | - Yasin Dagdas
- Gregor Mendel Institute, Austrian Academy of Sciences, Vienna Biocenter, Dr. Bohr-Gasse 3, 1030 Vienna, Austria
| | | | - Agnieszka Sirko
- Institute of Biochemistry and Biophysics Polish Academy of Sciences, Pawinskiego 5A, 02-106 Warsaw, Poland
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19
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Shen F, Gai J, Xing J, Guan J, Fu L, Li Q. Dynasore suppresses proliferation and induces apoptosis of the non-small-cell lung cancer cell line A549. Biochem Biophys Res Commun 2017; 495:1158-1166. [PMID: 29175207 DOI: 10.1016/j.bbrc.2017.11.109] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 11/15/2017] [Accepted: 11/17/2017] [Indexed: 01/09/2023]
Abstract
Lung cancer is the leading cause of cancer death worldwide, and most of all cases are non-small-cell lung cancer. Lung cancer is associated with dysregulation of mitochondrial fusion and fission, and inhibition of the fission regulator Dynamin-related protein 1 (Drp1) reduces proliferation and increases apoptosis of lung cancer cells. Dynasore is a small molecule non-selective inhibitor of the GTPase activity of dynamin 1, dynamin 2, and Drp1 in vivo and in vitro. Here, we investigated the effects of dynasore on the proliferation and apoptosis of A549 lung cancer cells, alone and in combination with the chemotherapeutic drug cisplatin. We found that cisplatin increased mitochondrial fission and dynamin 2 expression, whereas dynasore had the opposite effects. However, both cisplatin and dynasore independently induced mitochondrial oxidative stress, leading to mitochondrial dysfunction, reduced cell proliferation, and enhanced apoptosis. Importantly, dynasore significantly augmented the anti-cancer effects of cisplatin. To the best of our knowledge, this is the first report that dynasore inhibits proliferation and induces apoptosis of lung cancer cells, and enhances the inhibitory effects of cisplatin.
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Affiliation(s)
- Feifei Shen
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Junda Gai
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Jilin Xing
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Jingqian Guan
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Lin Fu
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - Qingchang Li
- Department of Pathology, College of Basic Medical Sciences, China Medical University, Shenyang, China.
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20
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Abstract
Macroautophagy is an intracellular pathway used for targeting of cellular components to the lysosome for their degradation and involves sequestration of cytoplasmic material into autophagosomes formed from a double membrane structure called the phagophore. The nucleation and elongation of the phagophore is tightly regulated by several autophagy-related (ATG) proteins, but also involves vesicular trafficking from different subcellular compartments to the forming autophagosome. Such trafficking must be tightly regulated by various intra- and extracellular signals to respond to different cellular stressors and metabolic states, as well as the nature of the cargo to become degraded. We are only starting to understand the interconnections between different membrane trafficking pathways and macroautophagy. This review will focus on the membrane trafficking machinery found to be involved in delivery of membrane, lipids, and proteins to the forming autophagosome and in the subsequent autophagosome fusion with endolysosomal membranes. The role of RAB proteins and their regulators, as well as coat proteins, vesicle tethers, and SNARE proteins in autophagosome biogenesis and maturation will be discussed.
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21
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Menzies FM, Fleming A, Caricasole A, Bento CF, Andrews SP, Ashkenazi A, Füllgrabe J, Jackson A, Jimenez Sanchez M, Karabiyik C, Licitra F, Lopez Ramirez A, Pavel M, Puri C, Renna M, Ricketts T, Schlotawa L, Vicinanza M, Won H, Zhu Y, Skidmore J, Rubinsztein DC. Autophagy and Neurodegeneration: Pathogenic Mechanisms and Therapeutic Opportunities. Neuron 2017; 93:1015-1034. [PMID: 28279350 DOI: 10.1016/j.neuron.2017.01.022] [Citation(s) in RCA: 762] [Impact Index Per Article: 108.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 12/11/2022]
Abstract
Autophagy is a conserved pathway that delivers cytoplasmic contents to the lysosome for degradation. Here we consider its roles in neuronal health and disease. We review evidence from mouse knockout studies demonstrating the normal functions of autophagy as a protective factor against neurodegeneration associated with intracytoplasmic aggregate-prone protein accumulation as well as other roles, including in neuronal stem cell differentiation. We then describe how autophagy may be affected in a range of neurodegenerative diseases. Finally, we describe how autophagy upregulation may be a therapeutic strategy in a wide range of neurodegenerative conditions and consider possible pathways and druggable targets that may be suitable for this objective.
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Affiliation(s)
- Fiona M Menzies
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Angeleen Fleming
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Andrea Caricasole
- Alzheimer's Research UK Cambridge Drug Discovery Institute, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK
| | - Carla F Bento
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Stephen P Andrews
- Alzheimer's Research UK Cambridge Drug Discovery Institute, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK
| | - Avraham Ashkenazi
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Jens Füllgrabe
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Anne Jackson
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Maria Jimenez Sanchez
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Cansu Karabiyik
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Floriana Licitra
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Ana Lopez Ramirez
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Mariana Pavel
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Claudia Puri
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Maurizio Renna
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Thomas Ricketts
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Lars Schlotawa
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Mariella Vicinanza
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Hyeran Won
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - Ye Zhu
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK
| | - John Skidmore
- Alzheimer's Research UK Cambridge Drug Discovery Institute, University of Cambridge, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0AH, UK
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Institute for Medical Research, Cambridge Biomedical Campus, Wellcome Trust/MRC Building, Cambridge Biomedical Campus, Hills Road, Cambridge CB2 0XY, UK.
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