1
|
Fanelli MJ, Welsh CM, Lui DS, Smulan LJ, Walker AK. Immunity-linked genes are stimulated by a membrane stress pathway linked to Golgi function and the ARF-1 GTPase. Sci Adv 2023; 9:eadi5545. [PMID: 38055815 PMCID: PMC10699786 DOI: 10.1126/sciadv.adi5545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 11/03/2023] [Indexed: 12/08/2023]
Abstract
Infection response and other immunity-linked genes (ILGs) were first named in Caenorhabditis elegans-based expression after pathogen challenge, but many are also up-regulated when lipid metabolism is perturbed. Why pathogen attack and metabolic changes both increase ILGs is unclear. We find that ILGs are activated when phosphatidylcholine (PC) levels change in membranes of secretory organelles in C. elegans. RNAi targeting of the ADP-ribosylation factor arf-1, which disrupts the Golgi and secretory function, also activates ILGs. Low PC limits ARF-1 function, suggesting a mechanism for ILG activation via lipid metabolism, as part of a membrane stress response acting outside the ER. RNAi of selected ILGs uncovered defects in the secretion of two GFP reporters and the accumulation of a pathogen-responsive complement C1r/C1s, Uegf, Bmp1 (CUB) domain fusion protein. Our data argue that up-regulation of some ILGs is a coordinated response to changes in trafficking and may act to counteract stress on secretory function.
Collapse
Affiliation(s)
- Matthew J. Fanelli
- Program in Molecular Medicine, UMASS Chan Medical School, Worcester, MA, USA
| | - Christofer M. Welsh
- Program in Molecular Medicine, UMASS Chan Medical School, Worcester, MA, USA
- Morningside School of Biomedical Sciences, UMASS Chan Medical School, Worcester, MA, USA
| | - Dominique S. Lui
- Program in Molecular Medicine, UMASS Chan Medical School, Worcester, MA, USA
| | - Lorissa J. Smulan
- Department of Medicine, UMASS Chan Medical School, Worcester, MA, USA
| | - Amy K. Walker
- Program in Molecular Medicine, UMASS Chan Medical School, Worcester, MA, USA
| |
Collapse
|
2
|
Wen TY, Wu XQ, Ye JR, Qiu YJ, Rui L, Zhang Y. Two Novel Bursaphelenchus xylophilus Kunitz Effector Proteins Using Different Infection and Survival Strategies to Suppress Immunity in Pine. Phytopathology 2023; 113:539-548. [PMID: 36976314 DOI: 10.1094/phyto-04-22-0127-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Pine wilt disease, caused by Bursaphelenchus xylophilus, results in tremendous economic loss in conifer production every year. To disturb the host immune responses, plant pathogens secrete a mass of effector proteins that facilitate the infection process. Although several effectors of B. xylophilus have been identified, detailed mechanisms of their functions remain largely unexplored. Here, we reveal two novel B. xylophilus Kunitz effectors, named BxKU1 and BxKU2, using different infection strategies to suppress immunity in Pinus thunbergii. We found that both BxKU1 and BxKU2 could suppress PsXEG1-triggered cell death and were present in the nucleus and cytoplasm in Nicotiana benthamiana. However, they had different three-dimensional structures and various expression patterns in B. xylophilus infection. In situ hybridization experiments showed that BxKU2 was expressed in the esophageal glands and ovaries, whereas BxKU1 was only expressed in the esophageal glands of females. We further confirmed that the morbidity was significantly decreased in P. thunbergii infected with B. xylophilus when BxKU1 and BxKU2 were silenced. The silenced BxKU2I, but not BxKU1, affected the reproduction and feeding rate of B. xylophilus. Moreover, BxKU1 and BxKU2 targeted to different proteins in P. thunbergii, but they all interacted with thaumatin-like protein 4 (TLP4) according to yeast two-hybrid screening. Collectively, our study showed that B. xylophilus could incorporate two Kunitz effectors in a multilayer strategy to counter immune response in P. thunbergii, which could help us better understand the interaction between plant and B. xylophilus.
Collapse
Affiliation(s)
- Tong-Yue Wen
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| | - Xiao-Qin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| | - Jian-Ren Ye
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| | - Yi-Jun Qiu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| | - Lin Rui
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| | - Yan Zhang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, 210037, China
- Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, 210037, China
| |
Collapse
|
3
|
Wang M, Du G, Fang J, Wang L, Guo Q, Zhang T, Li R. UGT440A1 Is Associated With Motility, Reproduction, and Pathogenicity of the Plant-Parasitic Nematode Bursaphelenchus xylophilus. Front Plant Sci 2022; 13:862594. [PMID: 35712574 PMCID: PMC9194688 DOI: 10.3389/fpls.2022.862594] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2022] [Accepted: 05/11/2022] [Indexed: 06/15/2023]
Abstract
Pine wilt disease (PWD) caused by Bursaphelenchus xylophilus is considered a major threat to pine forests worldwide. Uridine diphosphate (UDP)-glycosyltransferases (UGTs) catalyze the conjugation of small lipophilic compounds with sugars and play crucial roles in the detoxification and homeostatic processes in all living organisms. We investigated the molecular characteristics and biological functions of the gene UGT440A1 that encodes UGTs in B. xylophilus. The in situ hybridization results indicated that UGT440A1 is expressed in all developmental stages of B. xylophilus, particularly in the head, intestine, and hypodermis of the second-stage of juveniles (J2), third-stage of juveniles (J3) and fourth-stage of juveniles (J4) females and in almost the whole body of J4 males and adults. Recombinant UGT440A1 was observed mainly in the inclusion bodies, and the enzyme activity assay revealed that UGT440A1 could catalyze the glycosylation reaction of two types of flavonols (kaempferol and quercetin). RNA interference (RNAi) of UGT440A1 suppressed motility, feeding, and reproduction of B. xylophilus. Furthermore, UGT440A1 knockdown caused a delay in the development of PWD symptoms in the pine seedlings inoculated with the nematodes. These results suggest that UGT440A1 is involved in the pathogenic process of B. xylophilus and the information may facilitate a better understanding of the molecular mechanism of PWD.
Collapse
Affiliation(s)
- Min Wang
- Medical College, Qingdao University, Qingdao, China
| | - Guicai Du
- College of Life Sciences, Qingdao University, Qingdao, China
| | - Junna Fang
- Qingdao JiMo People’s Hospital, Qingdao, China
| | - Linsong Wang
- Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
| | - Qunqun Guo
- College of Life Sciences, Qingdao University, Qingdao, China
| | - Tingting Zhang
- College of Life Sciences, Qingdao University, Qingdao, China
| | - Ronggui Li
- College of Life Sciences, Qingdao University, Qingdao, China
| |
Collapse
|
4
|
Hartman JH, Widmayer SJ, Bergemann CM, King DE, Morton KS, Romersi RF, Jameson LE, Leung MCK, Andersen EC, Taubert S, Meyer JN. Xenobiotic metabolism and transport in Caenorhabditis elegans. J Toxicol Environ Health B Crit Rev 2021; 24:51-94. [PMID: 33616007 PMCID: PMC7958427 DOI: 10.1080/10937404.2021.1884921] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Caenorhabditis elegans has emerged as a major model in biomedical and environmental toxicology. Numerous papers on toxicology and pharmacology in C. elegans have been published, and this species has now been adopted by investigators in academic toxicology, pharmacology, and drug discovery labs. C. elegans has also attracted the interest of governmental regulatory agencies charged with evaluating the safety of chemicals. However, a major, fundamental aspect of toxicological science remains underdeveloped in C. elegans: xenobiotic metabolism and transport processes that are critical to understanding toxicokinetics and toxicodynamics, and extrapolation to other species. The aim of this review was to initially briefly describe the history and trajectory of the use of C. elegans in toxicological and pharmacological studies. Subsequently, physical barriers to chemical uptake and the role of the worm microbiome in xenobiotic transformation were described. Then a review of what is and is not known regarding the classic Phase I, Phase II, and Phase III processes was performed. In addition, the following were discussed (1) regulation of xenobiotic metabolism; (2) review of published toxicokinetics for specific chemicals; and (3) genetic diversity of these processes in C. elegans. Finally, worm xenobiotic transport and metabolism was placed in an evolutionary context; key areas for future research highlighted; and implications for extrapolating C. elegans toxicity results to other species discussed.
Collapse
Affiliation(s)
- Jessica H Hartman
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Samuel J Widmayer
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States
| | | | - Dillon E King
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Katherine S Morton
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Riccardo F Romersi
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| | - Laura E Jameson
- School of Mathematical and Natural Sciences, Arizona State University - West Campus, Glendale, Arizona, United States
| | - Maxwell C K Leung
- School of Mathematical and Natural Sciences, Arizona State University - West Campus, Glendale, Arizona, United States
| | - Erik C Andersen
- Department of Molecular Biosciences, Northwestern University, Evanston, Illinois, United States
| | - Stefan Taubert
- Dept. Of Medical Genetics, Centre for Molecular Medicine and Therapeutics, BC Children's Hospital Research Institute, the University of British Colombia, Vancouver, BC, Canada
| | - Joel N Meyer
- Nicholas School of the Environment, Duke University, Durham, North Carolina
| |
Collapse
|
5
|
Jasmer DP, Rosa BA, Tyagi R, Mitreva M. Rapid determination of nematode cell and organ susceptibility to toxic treatments. Int J Parasitol Drugs Drug Resist 2020; 14:167-182. [PMID: 33125935 PMCID: PMC7593349 DOI: 10.1016/j.ijpddr.2020.10.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 10/16/2020] [Accepted: 10/19/2020] [Indexed: 12/28/2022]
Abstract
In research focused on the intestine of parasitic nematodes, we recently identified small molecule inhibitors toxic to intestinal cells of larval Ascaris suum (nematode intestinal toxins/toxicants; “NITs”). Some NITs had anthelmintic activity across the phylogenetic diversity of the Nematoda. The whole-worm motility inhibition assay quantified anthelmintic activity, but worm responses to NITs in relation to pathology or affected molecular pathways was not acquired. In this study we extended this research to more comprehensively determine in whole larval A. suum the cells, organ systems, molecular targets, and potential cellular pathways involved in mechanisms of toxicity leading to cell death. The experimental system utilized fluorescent nuclear probes (bisbenzimide, propidium iodide), NITs, an A. suum larval parasite culture system and transcriptional responses (RNA-seq) to NITs. The approach provides for rapid resolution of NIT-induced cell death among organ systems (e.g. intestine, excretory, esophagus, hypodermis and seam cells, and nervous), discriminates among NITs based on cell death profiles, and identifies cells and organ systems with the greatest NIT sensitivity (e.g. intestine and apparent neuronal cells adjacent to the nerve ring). Application was extended to identify cells and organs sensitive to several existing anthelmintics. This approach also resolved intestinal cell death and irreparable damage induced in adult A. suum by two NITs, establishing a new model to elucidate relevant pathologic mechanisms in adult worms. RNA-seq analysis resolved A. suum genes responsive to treatments with three NITs, identifying dihydroorotate dehydrogenase (uridine synthesis) and RAB GTPase(s) (vesicle transport) as potential targets/pathways leading to cell death. A set of genes induced by all three NITs tested suggest common stress or survival responses activated by NITs. Beyond the presented specific lines of research, elements of the overall experimental system presented in this study have broad application toward systematic development of new anthelmintics. A unique rapid cell death assay was developed for parasitic nematodes. Multiple drug-like molecules cause widespread cell death in many organs of A. suum. Multiple cell and organ systems were validated as targets for anthelmintics. Potential drug targets/pathways were implicated in activating cell death processes.
Collapse
Affiliation(s)
- Douglas P Jasmer
- Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, WA, 99164, USA
| | - Bruce A Rosa
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Rahul Tyagi
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA
| | - Makedonka Mitreva
- Division of Infectious Diseases, Department of Medicine, Washington University School of Medicine, St. Louis, MO, 63110, USA; Department of Genetics, Washington University School of Medicine, St. Louis, MO 63110, St. Louis, MO, 63110, USA; McDonnell Genome Institute, Washington University School of Medicine, St. Louis, Missouri, 63108, USA.
| |
Collapse
|
6
|
Haghani A, Dalton HM, Safi N, Shirmohammadi F, Sioutas C, Morgan TE, Finch CE, Curran SP. Air Pollution Alters Caenorhabditis elegans Development and Lifespan: Responses to Traffic-Related Nanoparticulate Matter. J Gerontol A Biol Sci Med Sci 2019; 74:1189-1197. [PMID: 30828708 PMCID: PMC6625599 DOI: 10.1093/gerona/glz063] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 02/06/2019] [Indexed: 11/22/2022] Open
Abstract
Air pollution is a heterogeneous environmental toxicant that impacts humans throughout their life. We introduce Caenorhabditis elegans as a valuable air pollution model with its short lifespan, medium-throughput capabilities, and highly conserved biological pathways that impact healthspan. We exposed developmental and adult life stages of C. elegans to airborne nano-sized particulate matter (nPM) produced by traffic emissions and measured biological and molecular endpoints that changed in response. Acute nPM did not cause lethality in C. elegans, but short-term exposure during larval stage 1 caused delayed development. Gene expression responses to nPM exposure overlapped with responses of mouse and cell culture models of nPM exposure in previous studies. We showed further that the skn-1/Nrf2 antioxidant response has a role in the development and hormetic effects of nPM. This study introduces the worm as a new resource and complementary model for mouse and cultured cell systems to study air pollution toxicity across the lifespan.
Collapse
Affiliation(s)
- Amin Haghani
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles
| | - Hans M Dalton
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles
| | - Nikoo Safi
- Department of Biomedical Sciences, Center for Bioinformatics and Genomics, Cedars-Sinai Medical Center, Los Angeles, California
| | | | | | - Todd E Morgan
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles
| | - Caleb E Finch
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles
| | - Sean P Curran
- Leonard Davis School of Gerontology, University of Southern California, Los Angeles,Address correspondence to: Sean P. Curran, PhD, Leonard Davis School of Gerontology, University of Southern California, 3715 McClintock Avenue, Suite 350, Los Angeles, CA 90089. E-mail:
| |
Collapse
|
7
|
|
8
|
Ferguson GD, Bridge WJ. The glutathione system and the related thiol network in Caenorhabditis elegans. Redox Biol 2019; 24:101171. [PMID: 30901603 PMCID: PMC6429583 DOI: 10.1016/j.redox.2019.101171] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 03/07/2019] [Accepted: 03/13/2019] [Indexed: 01/09/2023] Open
Abstract
Advances in the field of redox biology have contributed to the understanding of the complexity of the thiol-based system in mediating signal transduction. The redox environment is the overall spatiotemporal balance of oxidation-reduction systems within the integrated compartments of the cell, tissues and whole organisms. The ratio of the reduced to disulfide glutathione redox couple (GSH:GSSG) is a key indicator of the redox environment and its associated cellular health. The reaction mechanisms of glutathione-dependent and related thiol-based enzymes play a fundamental role in the function of GSH as a redox regulator. Glutathione homeostasis is maintained by the balance of GSH synthesis (de novo and salvage pathways) and its utilization through its detoxification, thiol signalling, and antioxidant defence functions via GSH-dependent enzymes and free radical scavenging. As such, GSH acts in concert with the entire redox network to maintain reducing conditions in the cell. Caenorhabditis elegans offers a simple model to facilitate further understanding at the multicellular level of the physiological functions of GSH and the GSH-dependent redox network. This review discusses the C. elegans studies that have investigated glutathione and related systems of the redox network including; orthologs to the protein-encoding genes of GSH synthesis; glutathione peroxidases; glutathione-S-transferases; and the glutaredoxin, thioredoxin and peroxiredoxin systems.
Collapse
Affiliation(s)
- Gavin Douglas Ferguson
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia
| | - Wallace John Bridge
- School of Biotechnology and Biomolecular Sciences, The University of New South Wales, Sydney, NSW, 2052, Australia.
| |
Collapse
|
9
|
Fanelli E, Troccoli A, De Luca F. Functional Variation of Two Novel Cellulases, Pv-eng-5 and Pv-eng-8, and the Heat Shock 90 Gene, Pv-hsp-90, in Pratylenchus vulnus and Their Expression in Response to Different Temperature Stress. Int J Mol Sci 2018; 20:E107. [PMID: 30597892 PMCID: PMC6337429 DOI: 10.3390/ijms20010107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 12/12/2018] [Accepted: 12/20/2018] [Indexed: 11/18/2022] Open
Abstract
Functional characterization of two novel endoglucanase genes, Pv-eng-5 and Pv-eng-8, of the root-lesion nematode Pratylenchus vulnus was carried out. In situ-hybridization experiments revealed that Pv-eng-8 transcript was localized in the pharyngeal glands. Silencing of Pv-eng-5 and Pv-eng-8 resulted in a significant reduction of expression level (52% and 67%, respectively). Furthermore, the silencing of Pv-eng-8 determined a reduction (41%) in nematode reproduction, suggesting that treated nematodes are much less able to process food. Surprisingly, no significant difference on reproduction rate was observed with Pv-eng-5 dsRNA nematodes, suggesting a neofunctionalization of Pv-eng-5 despite the high similarity with nematode endoglucanases. Pratylenchus species are poikilothermic organisms showing close relationships with the environmental temperature. The effects of different temperature ranges revealed that the reproductive potential of P. vulnus increased with increasing temperature from 23 °C to 28 °C, but no reproduction was observed at 33 °C. In real time, increasing temperature from 23 °C to 28 °C the heat shock gene Pv-hsp-90 was differentially expressed in adult stages, while the levels of the effector genes Pv-eng-1 and Pv-eng-8 in females showed no significant differences compared to those observed at 23 °C, only in males Pv-eng-8 level decreased (45%). The upregulation of Pv-hsp-90 in both adult stages suggests a protective mechanism in order to cope with unfavorable environmental conditions.
Collapse
Affiliation(s)
- Elena Fanelli
- Istituto per la Protezione Sostenibile delle Piante (IPSP), SS-Bari, Consiglio Nazionale delle Ricerche, (CNR), 70126 Bari, Italy.
| | - Alberto Troccoli
- Istituto per la Protezione Sostenibile delle Piante (IPSP), SS-Bari, Consiglio Nazionale delle Ricerche, (CNR), 70126 Bari, Italy.
| | - Francesca De Luca
- Istituto per la Protezione Sostenibile delle Piante (IPSP), SS-Bari, Consiglio Nazionale delle Ricerche, (CNR), 70126 Bari, Italy.
| |
Collapse
|
10
|
Oliveira ADAB, Melo NDFM, Vieira ÉDS, Nogueira PAS, Coope A, Velloso LA, Dezonne RS, Ueira-Vieira C, Botelho FV, Gomes JDAS, Zanon RG. Palmitate treated-astrocyte conditioned medium contains increased glutathione and interferes in hypothalamic synaptic network in vitro. Neurochem Int 2018; 120:140-148. [DOI: 10.1016/j.neuint.2018.08.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 07/30/2018] [Accepted: 08/16/2018] [Indexed: 01/03/2023]
|
11
|
Salvadores N, Sanhueza M, Manque P, Court FA. Axonal Degeneration during Aging and Its Functional Role in Neurodegenerative Disorders. Front Neurosci 2017; 11:451. [PMID: 28928628 PMCID: PMC5591337 DOI: 10.3389/fnins.2017.00451] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/25/2017] [Indexed: 12/11/2022] Open
Abstract
Aging constitutes the main risk factor for the development of neurodegenerative diseases. This represents a major health issue worldwide that is only expected to escalate due to the ever-increasing life expectancy of the population. Interestingly, axonal degeneration, which occurs at early stages of neurodegenerative disorders (ND) such as Alzheimer's disease, Amyotrophic lateral sclerosis, and Parkinson's disease, also takes place as a consequence of normal aging. Moreover, the alteration of several cellular processes such as proteostasis, response to cellular stress and mitochondrial homeostasis, which have been described to occur in the aging brain, can also contribute to axonal pathology. Compelling evidence indicate that the degeneration of axons precedes clinical symptoms in NDs and occurs before cell body loss, constituting an early event in the pathological process and providing a potential therapeutic target to treat neurodegeneration before neuronal cell death. Although, normal aging and the development of neurodegeneration are two processes that are closely linked, the molecular basis of the switch that triggers the transition from healthy aging to neurodegeneration remains unrevealed. In this review we discuss the potential role of axonal degeneration in this transition and provide a detailed overview of the literature and current advances in the molecular understanding of the cellular changes that occur during aging that promote axonal degeneration and then discuss this in the context of ND.
Collapse
Affiliation(s)
- Natalia Salvadores
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
| | - Mario Sanhueza
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
| | - Patricio Manque
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile
| | - Felipe A Court
- Center for Integrative Biology, Faculty of Sciences, Universidad MayorSantiago, Chile.,Fondap Geroscience Center for Brain Health and MetabolismSantiago, Chile
| |
Collapse
|
12
|
Fukushige T, Smith HE, Miwa J, Krause MW, Hanover JA. A Genetic Analysis of the Caenorhabditis elegans Detoxification Response. Genetics 2017; 206:939-52. [PMID: 28428286 DOI: 10.1534/genetics.117.202515] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 04/18/2017] [Indexed: 12/11/2022] Open
Abstract
Oxidative damage contributes to human diseases of aging including diabetes, cancer, and cardiovascular disorders. Reactive oxygen species resulting from xenobiotic and endogenous metabolites are sensed by a poorly understood process, triggering a cascade of regulatory factors and leading to the activation of the transcription factor Nrf2 (Nuclear factor-erythroid-related factor 2, SKN-1 in Caenorhabditis elegans). Nrf2/SKN-1 activation promotes the induction of the phase II detoxification system that serves to limit oxidative stress. We have extended a previous C. elegans genetic approach to explore the mechanisms by which a phase II enzyme is induced by endogenous and exogenous oxidants. The xrep (xenobiotics response pathway) mutants were isolated as defective in their ability to properly regulate the induction of a glutathione S-transferase (GST) reporter. The xrep-1 gene was previously identified as wdr-23, which encodes a C. elegans homolog of the mammalian β-propeller repeat-containing protein WDR-23 Here, we identify and confirm the mutations in xrep-2, xrep-3, and xrep-4 The xrep-2 gene is alh-6, an ortholog of a human gene mutated in familial hyperprolinemia. The xrep-3 mutation is a gain-of-function allele of skn-1 The xrep-4 gene is F46F11.6, which encodes a F-box-containing protein. We demonstrate that xrep-4 alters the stability of WDR-23 (xrep-1), a key regulator of SKN-1 (xrep-3). Epistatic relationships among the xrep mutants and their interacting partners allow us to propose an ordered genetic pathway by which endogenous and exogenous stressors induce the phase II detoxification response.
Collapse
|
13
|
Wu CW, Wang Y, Choe KP. F-Box Protein XREP-4 Is a New Regulator of the Oxidative Stress Response in Caenorhabditis elegans. Genetics 2017; 206:859-71. [PMID: 28341649 DOI: 10.1534/genetics.117.200592] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Accepted: 03/16/2017] [Indexed: 12/18/2022] Open
Abstract
The transcription factor SKN-1 (Skinhead family member-1) in Caenorhabditis elegans is a homolog of the mammalian Nrf-2 protein and functions to promote oxidative stress resistance and longevity. SKN-1 mediates protection from reactive oxygen species (ROS) via the transcriptional activation of genes involved in antioxidant defense and phase II detoxification. Although many core regulators of SKN-1 have been identified, much remains unknown about this complex signaling pathway. We carried out an ethyl methanesulfonate (EMS) mutagenesis screen and isolated six independent mutants with attenuated SKN-1-dependent gene activation in response to acrylamide. All six were found to contain mutations in F46F11.6/xrep-4 (xenobiotics response pathways-4), which encodes an uncharacterized F-box protein. Loss of xrep-4 inhibits the skn-1-dependent expression of detoxification genes in response to prooxidants and decreases survival of oxidative stress, but does not shorten life span under standard culture conditions. XREP-4 interacts with the ubiquitin ligase component SKR-1 and the SKN-1 principal repressor WDR-23, and knockdown of xrep-4 increases nuclear localization of a WDR-23::GFP fusion protein. Furthermore, a missense mutation in the conserved XREP-4 F-box domain that reduces interaction with SKR-1 but not WDR-23 strongly attenuates SKN-1-dependent gene activation. These results are consistent with XREP-4 influencing the SKN-1 stress response by functioning as a bridge between WDR-23 and the ubiquitin ligase component SKR-1.
Collapse
|
14
|
Miranda-Vizuete A, Veal EA. Caenorhabditis elegans as a model for understanding ROS function in physiology and disease. Redox Biol 2016; 11:708-714. [PMID: 28193593 PMCID: PMC5304259 DOI: 10.1016/j.redox.2016.12.020] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 12/19/2016] [Indexed: 01/05/2023] Open
Abstract
ROS (reactive oxygen species) are potentially damaging by-products of aerobic metabolism which, unchecked, can have detrimental effects on cell function. However, it is now widely accepted that, at physiological levels, certain ROS play important roles in cell signaling, acting as second messengers to regulate cell choices that contribute to the development, adaptation and survival of plants and animals. Despite important recent advances in the biochemical tools available to study redox-signaling, the molecular mechanisms underlying most of these responses remain poorly understood, particularly in multicellular organisms. As we will review here, C. elegans has emerged as a powerful animal model to elucidate these and other aspects of redox biology.
Collapse
Affiliation(s)
- Antonio Miranda-Vizuete
- Instituto de Biomedicina de Sevilla, Hospital Universitario Virgen del Rocío/CSIC/Universidad de Sevilla, 41013 Sevilla, Spain.
| | - Elizabeth A Veal
- Institute for Cell and Molecular Biosciences, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK; Institute for Ageing, Newcastle University, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.
| |
Collapse
|
15
|
Papaevgeniou N, Sakellari M, Jha S, Tavernarakis N, Holmberg CI, Gonos ES, Chondrogianni N. 18α-Glycyrrhetinic Acid Proteasome Activator Decelerates Aging and Alzheimer's Disease Progression in Caenorhabditis elegans and Neuronal Cultures. Antioxid Redox Signal 2016; 25:855-869. [PMID: 26886723 PMCID: PMC5124744 DOI: 10.1089/ars.2015.6494] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AIMS Proteasomes are constituents of the cellular proteolytic networks that maintain protein homeostasis through regulated proteolysis of normal and abnormal (in any way) proteins. Genetically mediated proteasome activation in multicellular organisms has been shown to promote longevity and to exert protein antiaggregation activity. In this study, we investigate whether compound-mediated proteasome activation is feasible in a multicellular organism and we dissect the effects of such approach in aging and Alzheimer's disease (AD) progression. RESULTS Feeding of wild-type Caenorhabditis elegans with 18α-glycyrrhetinic acid (18α-GA; a previously shown proteasome activator in cell culture) results in enhanced levels of proteasome activities that lead to a skinhead-1- and proteasome activation-dependent life span extension. The elevated proteasome function confers lower paralysis rates in various AD nematode models accompanied by decreased Aβ deposits, thus ultimately decelerating the progression of AD phenotype. More importantly, similar positive results are also delivered when human and murine cells of nervous origin are subjected to 18α-GA treatment. INNOVATION This is the first report of the use of 18α-GA, a diet-derived compound as prolongevity and antiaggregation factor in the context of a multicellular organism. CONCLUSION Our results suggest that proteasome activation with downstream positive outcomes on aging and AD, an aggregation-related disease, is feasible in a nongenetic manipulation manner in a multicellular organism. Moreover, they unveil the need for identification of antiaging and antiamyloidogenic compounds among the nutrients found in our normal diet. Antioxid. Redox Signal. 25, 855-869.
Collapse
Affiliation(s)
- Nikoletta Papaevgeniou
- 1 Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation , Athens, Greece .,2 Faculty of Biology and Pharmacy, Institute of Nutrition, Friedrich Schiller University of Jena , Jena, Germany
| | - Marianthi Sakellari
- 1 Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation , Athens, Greece .,3 Medical School, Örebro University , Örebro, Sweden
| | - Sweta Jha
- 4 Translational Cancer Biology Program, Research Programs Unit, University of Helsinki , Helsinki, Finland
| | - Nektarios Tavernarakis
- 5 Institute of Molecular Biology and Biotechnology , Foundation for Research and Technology-Hellas, Heraklion, Greece .,6 Faculty of Medicine, Department of Basic Sciences, University of Crete , Heraklion, Greece
| | - Carina I Holmberg
- 4 Translational Cancer Biology Program, Research Programs Unit, University of Helsinki , Helsinki, Finland
| | - Efstathios S Gonos
- 1 Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation , Athens, Greece .,3 Medical School, Örebro University , Örebro, Sweden
| | - Niki Chondrogianni
- 1 Institute of Biology, Medicinal Chemistry and Biotechnology, National Hellenic Research Foundation , Athens, Greece
| |
Collapse
|
16
|
Park HR, Oh R, Wagner P, Panganiban R, Lu Q. New Insights Into Cellular Stress Responses to Environmental Metal Toxicants. Int Rev Cell Mol Biol 2016; 331:55-82. [PMID: 28325215 DOI: 10.1016/bs.ircmb.2016.10.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Exposures to metal toxicants in the environment disrupt normal physiological functions and have been linked to the development of a myriad of human diseases. While the molecular and cellular mechanisms underlying metal toxicities remain to be fully understood, it is well appreciated that metal toxicants induce cellular stresses and that how cells respond to the stresses plays an important role in metal toxicity. In this review, we focus on how metal exposures induce stresses in the endoplasmic reticulum (ER) to elicit the unfolded protein response (UPR). We document the emerging evidence that induction of ER stress and UPR in the development of human diseases is associated with metal exposures. We also discuss the role of the interplay between ER stress and oxidative stress in metal toxicity. Finally, we review recent advances in functional genomics approaches and discuss how applications of these new tools could help elucidate the molecular mechanisms underlying cellular stresses induced by environmental metal toxicants.
Collapse
Affiliation(s)
- H-R Park
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - R Oh
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - P Wagner
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - R Panganiban
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States
| | - Q Lu
- Program in Molecular and Integrative Physiological Sciences, Harvard T.H. Chan School of Public Health, Boston, MA, United States.
| |
Collapse
|
17
|
Wu CW, Deonarine A, Przybysz A, Strange K, Choe KP. The Skp1 Homologs SKR-1/2 Are Required for the Caenorhabditis elegans SKN-1 Antioxidant/Detoxification Response Independently of p38 MAPK. PLoS Genet 2016; 12:e1006361. [PMID: 27776126 PMCID: PMC5077136 DOI: 10.1371/journal.pgen.1006361] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2016] [Accepted: 09/13/2016] [Indexed: 01/12/2023] Open
Abstract
SKN-1/Nrf are the primary antioxidant/detoxification response transcription factors in animals and they promote health and longevity in many contexts. SKN-1/Nrf are activated by a remarkably broad-range of natural and synthetic compounds and physiological conditions. Defining the signaling mechanisms that regulate SKN-1/Nrf activation provides insights into how cells coordinate responses to stress. Nrf2 in mammals is regulated in part by the redox sensor repressor protein named Keap1. In C. elegans, the p38 MAPK cascade in the intestine activates SKN-1 during oxidative stress by promoting its nuclear accumulation. Interestingly, we find variation in the kinetics of p38 MAPK activation and tissues with SKN-1 nuclear accumulation among different pro-oxidants that all trigger strong induction of SKN-1 target genes. Using genome-wide RNAi screening, we identify new genes that are required for activation of the core SKN-1 target gene gst-4 during exposure to the natural pro-oxidant juglone. Among 10 putative activators identified in this screen was skr-1/2, highly conserved homologs of yeast and mammalian Skp1, which function to assemble protein complexes. Silencing of skr-1/2 inhibits induction of SKN-1 dependent detoxification genes and reduces resistance to pro-oxidants without decreasing p38 MAPK activation. Global transcriptomics revealed strong correlation between genes that are regulated by SKR-1/2 and SKN-1 indicating a high degree of specificity. We also show that SKR-1/2 functions upstream of the WD40 repeat protein WDR-23, which binds to and inhibits SKN-1. Together, these results identify a novel p38 MAPK independent signaling mechanism that activates SKN-1 via SKR-1/2 and involves WDR-23.
Collapse
Affiliation(s)
- Cheng-Wei Wu
- Department of Biology and Genetics Institute, University of Florida, Gainesville, FL 32611, USA
| | - Andrew Deonarine
- Department of Cell Biology, Microbiology, and Molecular Biology, University of South Florida, Tampa, FL, 33620
| | - Aaron Przybysz
- Department of Anesthesiology, University of Michigan, Ann Arbor, MI 48109
| | - Kevin Strange
- The MDI Biological Laboratory, Salisbury Cove, ME 04672
| | - Keith P. Choe
- Department of Biology and Genetics Institute, University of Florida, Gainesville, FL 32611, USA
- * E-mail:
| |
Collapse
|
18
|
Ferraz RC, Camara H, De-Souza EA, Pinto S, Pinca APF, Silva RC, Sato VN, Castilho BA, Mori MA. IMPACT is a GCN2 inhibitor that limits lifespan in Caenorhabditis elegans. BMC Biol 2016; 14:87. [PMID: 27717342 PMCID: PMC5054600 DOI: 10.1186/s12915-016-0301-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 08/18/2016] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The General Control Nonderepressible 2 (GCN2) kinase is a conserved member of the integrated stress response (ISR) pathway that represses protein translation and helps cells to adapt to conditions of nutrient shortage. As such, GCN2 is required for longevity and stress resistance induced by dietary restriction (DR). IMPACT is an ancient protein that inhibits GCN2. RESULTS Here, we tested whether IMPACT down-regulation mimics the effects of DR in C. elegans. Knockdown of the C. elegans IMPACT homolog impt-1 activated the ISR pathway and increased lifespan and stress resistance of worms in a gcn-2-dependent manner. Impt-1 knockdown exacerbated DR-induced longevity and required several DR-activated transcription factors to extend lifespan, among them SKN-1 and DAF-16, which were induced during larval development and adulthood, respectively, in response to impt-1 RNAi. CONCLUSIONS IMPACT inhibits the ISR pathway, thus limiting the activation of stress response factors that are beneficial during aging and required under DR.
Collapse
Affiliation(s)
- Rafael C Ferraz
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Henrique Camara
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- Department of Biochemistry and Tissue Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Evandro A De-Souza
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- Department of Biochemistry and Tissue Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Silas Pinto
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- Department of Biochemistry and Tissue Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Ana Paula F Pinca
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
- Department of Biochemistry and Tissue Biology, Universidade Estadual de Campinas, Campinas, Brazil
| | - Richard C Silva
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Vitor N Sato
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Beatriz A Castilho
- Department of Microbiology, Immunology and Parasitology, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil
| | - Marcelo A Mori
- Department of Biophysics, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, Brazil.
- Department of Biochemistry and Tissue Biology, Universidade Estadual de Campinas, Campinas, Brazil.
| |
Collapse
|
19
|
Espada M, Silva AC, Eves van den Akker S, Cock PJA, Mota M, Jones JT. Identification and characterization of parasitism genes from the pinewood nematode Bursaphelenchus xylophilus reveals a multilayered detoxification strategy. Mol Plant Pathol 2016; 17:286-95. [PMID: 25981957 PMCID: PMC6638532 DOI: 10.1111/mpp.12280] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The migratory endoparasitic nematode Bursaphelenchus xylophilus, which is the causal agent of pine wilt disease, has phytophagous and mycetophagous phases during its life cycle. This highly unusual feature distinguishes it from other plant-parasitic nematodes and requires profound changes in biology between modes. During the phytophagous stage, the nematode migrates within pine trees, feeding on the contents of parenchymal cells. Like other plant pathogens, B. xylophilus secretes effectors from pharyngeal gland cells into the host during infection. We provide the first description of changes in the morphology of these gland cells between juvenile and adult life stages. Using a comparative transcriptomics approach and an effector identification pipeline, we identify numerous novel parasitism genes which may be important for the mediation of interactions of B. xylophilus with its host. In-depth characterization of all parasitism genes using in situ hybridization reveals two major categories of detoxification proteins, those specifically expressed in either the pharyngeal gland cells or the digestive system. These data suggest that B. xylophilus incorporates effectors in a multilayer detoxification strategy in order to protect itself from host defence responses during phytophagy.
Collapse
Affiliation(s)
- Margarida Espada
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Ana Cláudia Silva
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- Biology Department, University of Gent, KL Ledeganckstraat 35, B9000, Gent, Belgium
| | | | - Peter J A Cock
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Manuel Mota
- NemaLab/ICAAM-Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
| | - John T Jones
- Cell and Molecular Sciences Group/Information and Computer Sciences Group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
- Biology Department, University of Gent, KL Ledeganckstraat 35, B9000, Gent, Belgium
- School of Biology, University of St Andrews, North Haugh, St Andrews, KY16 9TZ, UK
| |
Collapse
|
20
|
Gomes LC, Odedra D, Dikic I, Pohl C. Autophagy and modular restructuring of metabolism control germline tumor differentiation and proliferation in C. elegans. Autophagy 2016; 12:529-46. [PMID: 26759963 PMCID: PMC4835962 DOI: 10.1080/15548627.2015.1136771] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Autophagy can act either as a tumor suppressor or as a survival mechanism for established tumors. To understand how autophagy plays this dual role in cancer, in vivo models are required. By using a highly heterogeneous C. elegans germline tumor, we show that autophagy-related proteins are expressed in a specific subset of tumor cells, neurons. Inhibition of autophagy impairs neuronal differentiation and increases tumor cell number, resulting in a shorter life span of animals with tumors, while induction of autophagy extends their life span by impairing tumor proliferation. Fasting of animals with fully developed tumors leads to a doubling of their life span, which depends on modular changes in transcription including switches in transcription factor networks and mitochondrial metabolism. Hence, our results suggest that metabolic restructuring, cell-type specific regulation of autophagy and neuronal differentiation constitute central pathways preventing growth of heterogeneous tumors.
Collapse
Affiliation(s)
- Ligia C Gomes
- a Buchmann Institute for Molecular Life Sciences, Goethe University , Frankfurt (Main) , Germany.,b Institute of Biochemistry II, School of Medicine, Goethe University , Frankfurt (Main) , Germany
| | - Devang Odedra
- a Buchmann Institute for Molecular Life Sciences, Goethe University , Frankfurt (Main) , Germany.,b Institute of Biochemistry II, School of Medicine, Goethe University , Frankfurt (Main) , Germany
| | - Ivan Dikic
- a Buchmann Institute for Molecular Life Sciences, Goethe University , Frankfurt (Main) , Germany.,b Institute of Biochemistry II, School of Medicine, Goethe University , Frankfurt (Main) , Germany.,c Department of Immunology and Medical Genetics , University of Split, School of Medicine , Split , Croatia
| | - Christian Pohl
- a Buchmann Institute for Molecular Life Sciences, Goethe University , Frankfurt (Main) , Germany.,b Institute of Biochemistry II, School of Medicine, Goethe University , Frankfurt (Main) , Germany
| |
Collapse
|
21
|
Carvalho AC, Gomes AC, Pereira-Wilson C, Lima CF. Redox-dependent induction of antioxidant defenses by phenolic diterpenes confers stress tolerance in normal human skin fibroblasts: Insights on replicative senescence. Free Radic Biol Med 2015; 83:262-72. [PMID: 25744415 DOI: 10.1016/j.freeradbiomed.2015.02.022] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2014] [Revised: 02/06/2015] [Accepted: 02/20/2015] [Indexed: 12/12/2022]
Abstract
Mild stress-induced hormesis represents a promising strategy for targeting the age-related accumulation of molecular damage and, therefore, for preventing diseases and achieving healthy aging. Fruits, vegetables, and spices contain a wide variety of hormetic phytochemicals, which may explain the beneficial health effects associated with the consumption of these dietary components. In the present study, the induction of cellular antioxidant defenses by the phenolic diterpenes carnosic acid (CA) and carnosol (CS) were studied in normal human skin fibroblasts, and insights into the aging process at the cellular level investigated. We observed that CA and CS induced several cytoprotective enzymes and antioxidant defenses in human fibroblasts, whose induction was dependent on the cellular redox state for CS and associated with Nrf2 signaling for both compounds. The stress response elicited by preincubation with CS conferred a cytoprotective action against a following oxidant challenge with tert-butyl hydroperoxide, confirming its hormetic effect. Preincubation of normal fibroblasts with CS also protected against hydrogen peroxide-induced premature senescence. Furthermore, cultivation of middle passage normal human skin fibroblasts in the presence of CS ameliorated the physiological state of cells during replicative senescence. Our results support the view that mild stress-induced antioxidant defenses by CS can confer stress tolerance in normal cells and may have important implications in the promotion of healthy aging.
Collapse
Affiliation(s)
- Ana C Carvalho
- CITAB (Centre for the Research and Technology of Agro-Environmental and Biological Sciences), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal; CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Andreia C Gomes
- CBMA (Centre of Molecular and Environmental Biology), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Cristina Pereira-Wilson
- CITAB (Centre for the Research and Technology of Agro-Environmental and Biological Sciences), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - Cristovao F Lima
- CITAB (Centre for the Research and Technology of Agro-Environmental and Biological Sciences), Department of Biology, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal.
| |
Collapse
|
22
|
Grants JM, Goh GYS, Taubert S. The Mediator complex of Caenorhabditis elegans: insights into the developmental and physiological roles of a conserved transcriptional coregulator. Nucleic Acids Res 2015; 43:2442-53. [PMID: 25634893 PMCID: PMC4344494 DOI: 10.1093/nar/gkv037] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The Mediator multiprotein complex (‘Mediator’) is an important transcriptional coregulator that is evolutionarily conserved throughout eukaryotes. Although some Mediator subunits are essential for the transcription of all protein-coding genes, others influence the expression of only subsets of genes and participate selectively in cellular signaling pathways. Here, we review the current knowledge of Mediator subunit function in the nematode Caenorhabditis elegans, a metazoan in which established and emerging genetic technologies facilitate the study of developmental and physiological regulation in vivo. In this nematode, unbiased genetic screens have revealed critical roles for Mediator components in core developmental pathways such as epidermal growth factor (EGF) and Wnt/β-catenin signaling. More recently, important roles for C. elegans Mediator subunits have emerged in the regulation of lipid metabolism and of systemic stress responses, engaging conserved transcription factors such as nuclear hormone receptors (NHRs). We emphasize instances where similar functions for individual Mediator subunits exist in mammals, highlighting parallels between Mediator subunit action in nematode development and in human cancer biology. We also discuss a parallel between the association of the Mediator subunit MED12 with several human disorders and the role of its C. elegans ortholog mdt-12 as a regulatory hub that interacts with numerous signaling pathways.
Collapse
Affiliation(s)
- Jennifer M Grants
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Centre for Molecular Medicine and Therapeutics, Child & Family Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Grace Y S Goh
- Centre for Molecular Medicine and Therapeutics, Child & Family Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Graduate Program in Cell and Developmental Biology, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| | - Stefan Taubert
- Department of Medical Genetics, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Centre for Molecular Medicine and Therapeutics, Child & Family Research Institute, University of British Columbia, Vancouver, BC V5Z 4H4, Canada Graduate Program in Cell and Developmental Biology, University of British Columbia, Vancouver, BC V5Z 4H4, Canada
| |
Collapse
|