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Corne A, Adolphe F, Estaquier J, Gaumer S, Corsi JM. ATF4 Signaling in HIV-1 Infection: Viral Subversion of a Stress Response Transcription Factor. Biology (Basel) 2024; 13:146. [PMID: 38534416 DOI: 10.3390/biology13030146] [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] [Subscribe] [Scholar Register] [Received: 01/20/2024] [Revised: 02/13/2024] [Accepted: 02/20/2024] [Indexed: 03/28/2024]
Abstract
Cellular integrated stress response (ISR), the mitochondrial unfolded protein response (UPRmt), and IFN signaling are associated with viral infections. Activating transcription factor 4 (ATF4) plays a pivotal role in these pathways and controls the expression of many genes involved in redox processes, amino acid metabolism, protein misfolding, autophagy, and apoptosis. The precise role of ATF4 during viral infection is unclear and depends on cell hosts, viral agents, and models. Furthermore, ATF4 signaling can be hijacked by pathogens to favor viral infection and replication. In this review, we summarize the ATF4-mediated signaling pathways in response to viral infections, focusing on human immunodeficiency virus 1 (HIV-1). We examine the consequences of ATF4 activation for HIV-1 replication and reactivation. The role of ATF4 in autophagy and apoptosis is explored as in the context of HIV-1 infection programmed cell deaths contribute to the depletion of CD4 T cells. Furthermore, ATF4 can also participate in the establishment of innate and adaptive immunity that is essential for the host to control viral infections. We finally discuss the putative role of the ATF4 paralogue, named ATF5, in HIV-1 infection. This review underlines the role of ATF4 at the crossroads of multiple processes reflecting host-pathogen interactions.
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Affiliation(s)
- Adrien Corne
- Laboratoire de Génétique et Biologie Cellulaire, Université Versailles-Saint-Quentin-en-Yvelines, Université Paris-Saclay, 78000 Versailles, France
- CHU de Québec Research Center, Laval University, Quebec City, QC G1V 4G2, Canada
| | - Florine Adolphe
- Laboratoire de Génétique et Biologie Cellulaire, Université Versailles-Saint-Quentin-en-Yvelines, Université Paris-Saclay, 78000 Versailles, France
| | - Jérôme Estaquier
- CHU de Québec Research Center, Laval University, Quebec City, QC G1V 4G2, Canada
- INSERM U1124, Université Paris Cité, 75006 Paris, France
| | - Sébastien Gaumer
- Laboratoire de Génétique et Biologie Cellulaire, Université Versailles-Saint-Quentin-en-Yvelines, Université Paris-Saclay, 78000 Versailles, France
| | - Jean-Marc Corsi
- Laboratoire de Génétique et Biologie Cellulaire, Université Versailles-Saint-Quentin-en-Yvelines, Université Paris-Saclay, 78000 Versailles, France
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Hoareau M, Rincheval-Arnold A, Gaumer S, Guénal I. DREAM a little dREAM of DRM: Model organisms and conservation of DREAM-like complexes: Model organisms uncover the mechanisms of DREAM-mediated transcription regulation. Bioessays 2024; 46:e2300125. [PMID: 38059789 DOI: 10.1002/bies.202300125] [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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 11/23/2023] [Accepted: 11/24/2023] [Indexed: 12/08/2023]
Abstract
DREAM complexes are transcriptional regulators that control the expression of hundreds to thousands of target genes involved in the cell cycle, quiescence, differentiation, and apoptosis. These complexes contain many subunits that can vary according to the considered target genes. Depending on their composition and the nature of the partners they recruit, DREAM complexes control gene expression through diverse mechanisms, including chromatin remodeling, transcription cofactor and factor recruitment at various genomic binding sites. This complexity is particularly high in mammals. Since the discovery of the first dREAM complex (drosophila Rb, E2F, and Myb) in Drosophila melanogaster, model organisms such as Caenorhabditis elegans, and plants allowed a deeper understanding of the processes regulated by DREAM-like complexes. Here, we review the conservation of these complexes. We discuss the contribution of model organisms to the study of DREAM-mediated transcriptional regulatory mechanisms and their relevance in characterizing novel activities of DREAM complexes.
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Affiliation(s)
- Marion Hoareau
- Université Paris-Saclay, UVSQ, LGBC, Versailles, France
- Université PSL, EPHE, Paris, France
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3
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Breban M, Glatigny S, Cherqaoui B, Beaufrère M, Lauraine M, Rincheval-Arnold A, Gaumer S, Guénal I, Araujo LM. Lessons on SpA pathogenesis from animal models. Semin Immunopathol 2021; 43:207-219. [PMID: 33449154 DOI: 10.1007/s00281-020-00832-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Accepted: 12/15/2020] [Indexed: 12/31/2022]
Abstract
Understanding the complex mechanisms underlying a disorder such as spondyloarthritis (SpA) may benefit from studying animal models. Several suitable models have been developed, in particular to investigate the role of genetic factors predisposing to SpA, including HLA-B27, ERAP1, and genes related to the interleukin (IL)-23/IL-17 axis. One of the best examples of such research is the HLA-B27 transgenic rat model that fostered the emergence of original theories regarding HLA-B27 pathogenicity, including dysregulation of innate immunity, contribution of the adaptive immune system to chronic inflammation, and influence of the microbiota on disease development. Very recently, a new model of HLA-B27 transgenic Drosophila helped to expand further some of those theories in an unexpected direction involving the TGFβ/BMP family of mediators. On the other hand, several spontaneous, inducible, and/or genetically modified mouse models-including SKG mouse, TNFΔARE mouse and IL-23-inducible mouse model of SpA-have highlighted the importance of TNFα and IL-23/IL-17 axis in the development of SpA manifestations. Altogether, those animal models afford not only to study disease mechanism but also to investigate putative therapeutic targets.
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Affiliation(s)
- Maxime Breban
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France. .,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France. .,Service de Rhumatologie, Hôpital Ambroise Paré, AP-HP, 9 ave Charles de Gaulle, 92100, Boulogne, France.
| | - Simon Glatigny
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France.,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
| | - Bilade Cherqaoui
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France.,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
| | - Marie Beaufrère
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France.,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
| | - Marc Lauraine
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France.,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
| | - Aurore Rincheval-Arnold
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France
| | - Sébastien Gaumer
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France
| | - Isabelle Guénal
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France
| | - Luiza M Araujo
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/Université Paris Saclay, 2 ave de la Source de la Bièvre, 78180, Montigny-le-Bretonneux, France.,Laboratoire d'Excellence Inflamex, Université Paris Descartes, Sorbonne-Paris-Cité, Paris, France
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Grandon B, Rincheval-Arnold A, Jah N, Corsi JM, Araujo LM, Glatigny S, Prevost E, Roche D, Chiocchia G, Guénal I, Gaumer S, Breban M. HLA-B27 alters BMP/TGFβ signalling in Drosophila, revealing putative pathogenic mechanism for spondyloarthritis. Ann Rheum Dis 2019; 78:1653-1662. [PMID: 31563893 DOI: 10.1136/annrheumdis-2019-215832] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 09/08/2019] [Accepted: 09/09/2019] [Indexed: 01/16/2023]
Abstract
OBJECTIVES The human leucocyte antigen (HLA)-B27 confers an increased risk of spondyloarthritis (SpA) by unknown mechanism. The objective of this work was to uncover HLA-B27 non-canonical properties that could explain its pathogenicity, using a new Drosophila model. METHODS We produced transgenic Drosophila expressing the SpA-associated HLA-B*27:04 or HLA-B*27:05 subtypes, or the non-associated HLA-B*07:02 allele, alone or in combination with human β2-microglobulin (hβ2m), under tissue-specific drivers. Consequences of transgenes expression in Drosophila were examined and affected pathways were investigated by the genetic interaction experiments. Predictions of the model were further tested in immune cells from patients with SpA. RESULTS Loss of crossveins in the wings and a reduced eye phenotype were observed after expression of HLA-B*27:04 or HLA-B*27:05 in Drosophila but not in fruit flies expressing the non-associated HLA-B*07:02 allele. These HLA-B27-induced phenotypes required the presence of hβ2m that allowed expression of well-folded HLA-B conformers at the cell surface. Loss of crossveins resulted from a dominant negative effect of HLA-B27 on the type I bone morphogenetic protein (BMP) receptor saxophone (Sax) with which it interacted, resulting in elevated mothers against decapentaplegic (Mad, a Drosophila receptor-mediated Smad) phosphorylation. Likewise, in immune cells from patients with SpA, HLA-B27 specifically interacted with activin receptor-like kinase-2 (ALK2), the mammalian Sax ortholog, at the cell surface and elevated Smad phosphorylation was observed in response to activin A and transforming growth factor β (TGFβ). CONCLUSIONS Antagonistic interaction of HLA-B27 with ALK2, which exerts inhibitory functions on the TGFβ/BMP signalling pathway at the cross-road between inflammation and ossification, could adequately explain SpA development.
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Affiliation(s)
- Benjamin Grandon
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France.,Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Aurore Rincheval-Arnold
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France
| | - Nadège Jah
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Jean-Marc Corsi
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France
| | - Luiza M Araujo
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Simon Glatigny
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Erwann Prevost
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France.,Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Delphine Roche
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France
| | - Gilles Chiocchia
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France
| | - Isabelle Guénal
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France
| | - Sébastien Gaumer
- LGBC, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, Montigny-le-Bretonneux, France
| | - Maxime Breban
- Infection & Inflammation, UMR 1173, Inserm, UVSQ/ Université Paris Saclay, Montigny-le-Bretonneux, France .,Rheumatology, Ambroise Paré Hospital, Boulogne Billancourt, France
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Perochon J, Grandon B, Roche D, Wintz C, Demay Y, Mignotte B, Szuplewski S, Gaumer S. The endoplasmic reticulum unfolded protein response varies depending on the affected region of the tissue but independently from the source of stress. Cell Stress Chaperones 2019; 24:817-824. [PMID: 31144193 PMCID: PMC6629755 DOI: 10.1007/s12192-019-01009-8] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Revised: 04/30/2019] [Accepted: 05/15/2019] [Indexed: 10/26/2022] Open
Abstract
Accumulation of unfolded proteins and calcium dyshomeostasis induces endoplasmic reticulum (ER) stress, which can be resolved by the unfolded protein response (UPR). We have previously reported that activation of the PERK/ATF4 branch of the UPR, by overexpressing Presenilin in part of the vestigial domain of Drosophila wing imaginal discs, induces both a caspase-dependent apoptosis and a Slpr/JNK/Dilp8-dependent developmental delay that allows compensation of cell death in the tissue. Recently, dDad1 depletion in Drosophila in engrailed-expressing cells of wing imaginal discs was also reported to activate the PERK/ATF4 branch but induced Mekk1/JNK-dependent apoptosis. Here, we assessed whether the stressed cell location in the wing imaginal disc could explain these differences in response to chronic ER stress or whether the stress source could be responsible for the signaling discrepancy. To address this question, we overexpressed a Rhodopsin-1 mutant prone to aggregate either in vestigial- or engrailed-expressing cells. We observed similar responses to the Presenilin overexpression in the vestigial domain and to the dDad1 depletion in the engrailed domain. Therefore, the consequences of a PERK/ATF4 branch activation depend on the position of the cell in the Drosophila wing imaginal disc, suggesting interactions of PERK signaling with developmental pathways involved in the determination or maintenance of wing domains.
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Affiliation(s)
- Jessica Perochon
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
- Present Address: Wolfson Wohl Cancer Research Centre, Institute of Cancer Sciences, University of Glasgow, Garscube Estate, Switchback Road, Glasgow, G61 1QH UK
| | - Benjamin Grandon
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Delphine Roche
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Christine Wintz
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Yohan Demay
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Bernard Mignotte
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Sébastien Szuplewski
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
| | - Sébastien Gaumer
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, UVSQ/Université Paris-Saclay, EPHE/PSL Research University, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bretonneux, France
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Gaumer S. SP0138 The Fruit Fly, as A Tool To Study ER Stress. Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.6390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Vinatier G, Corsi JM, Mignotte B, Gaumer S. Quantification of Ataxin-3 and Ataxin-7 aggregates formed in vivo in Drosophila reveals a threshold of aggregated polyglutamine proteins associated with cellular toxicity. Biochem Biophys Res Commun 2015. [PMID: 26210447 DOI: 10.1016/j.bbrc.2015.07.071] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Polyglutamine diseases are nine dominantly inherited neurodegenerative pathologies caused by the expansion of a polyglutamine domain in a protein responsible for the disease. This expansion leads to protein aggregation, inclusion formation and toxicity. Despite numerous studies focusing on the subject, whether soluble polyglutamine proteins are responsible for toxicity or not remains debated. To focus on this matter, we evaluated the level of soluble and insoluble truncated pathological Ataxin-3 in vivo in Drosophila, in presence or absence of two suppressors (i.e. Hsp70 and non-pathological Ataxin-3) and along aging. Suppressing truncated Ataxin-3-induced toxicity resulted in a lowered level of aggregated polyglutamine protein. Interestingly, aggregates accumulated as flies aged and reached a maximum level when cell death was detected. Our results were similar with two other pathological polyglutamine proteins, namely truncated Ataxin-7 and full-length Ataxin-3. Our data suggest that accumulation of insoluble aggregates beyond a critical threshold could be responsible for toxicity.
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Affiliation(s)
- Gérald Vinatier
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, Université Versailles-St-Quentin-en-Yvelines, Ecole Pratique des Hautes Etudes, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bx, France
| | - Jean-Marc Corsi
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, Université Versailles-St-Quentin-en-Yvelines, Ecole Pratique des Hautes Etudes, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bx, France
| | - Bernard Mignotte
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, Université Versailles-St-Quentin-en-Yvelines, Ecole Pratique des Hautes Etudes, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bx, France
| | - Sébastien Gaumer
- Laboratoire de Génétique et Biologie Cellulaire, EA4589, Université Versailles-St-Quentin-en-Yvelines, Ecole Pratique des Hautes Etudes, 2 rue de la source de la Bièvre, 78180 Montigny-le-Bx, France.
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Colin J, Garibal J, Clavier A, Szuplewski S, Risler Y, Milet C, Gaumer S, Guénal I, Mignotte B. Screening of suppressors of bax-induced cell death identifies glycerophosphate oxidase-1 as a mediator of debcl-induced apoptosis in Drosophila. Genes Cancer 2015; 6:241-253. [PMID: 26124923 PMCID: PMC4482245 DOI: 10.18632/genesandcancer.68] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [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: 02/09/2015] [Accepted: 06/06/2015] [Indexed: 01/20/2023] Open
Abstract
Members of the Bcl-2 family are key elements of the apoptotic machinery. In mammals, this multigenic family contains about twenty members, which either promote or inhibit apoptosis. We have previously shown that the mammalian pro-apoptotic Bcl-2 family member Bax is very efficient in inducing apoptosis in Drosophila, allowing the study of bax-induced cell death in a genetic animal model. We report here the results of the screening of a P[UAS]-element insertion library performed to identify gene products that modify the phenotypes induced by the expression of bax in Drosophila melanogaster. We isolated 17 putative modifiers involved in various function or process: the ubiquitin/proteasome pathway; cell growth, proliferation and death; pathfinding and cell adhesion; secretion and extracellular signaling; metabolism and oxidative stress. Most of these suppressors also inhibit debcl-induced phenotypes, suggesting that the activities of both proteins can be modulated in part by common signaling or metabolic pathways. Among these suppressors, Glycerophosphate oxidase-1 is found to participate in debcl-induced apoptosis by increasing mitochondrial reactive oxygen species accumulation.
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Affiliation(s)
- Jessie Colin
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Ecole Pratique des Hautes Etudes, Laboratoire de Génétique Moléculaire et Physiologique, Montigny-le-Bretonneux, France
| | - Julie Garibal
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Ecole Pratique des Hautes Etudes, Laboratoire de Génétique Moléculaire et Physiologique, Montigny-le-Bretonneux, France
| | - Amandine Clavier
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Ecole Pratique des Hautes Etudes, Laboratoire de Génétique Moléculaire et Physiologique, Montigny-le-Bretonneux, France
| | - Sébastien Szuplewski
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France
| | - Yanick Risler
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France
| | - Cécile Milet
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Ecole Pratique des Hautes Etudes, Laboratoire de Génétique Moléculaire et Physiologique, Montigny-le-Bretonneux, France
| | - Sébastien Gaumer
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France
| | - Isabelle Guénal
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Co-senior authors
| | - Bernard Mignotte
- Université Versailles St-Quentin, Laboratoire de Génétique et Biologie Cellulaire, Montigny-le-Bretonneux, France.,Ecole Pratique des Hautes Etudes, Laboratoire de Génétique Moléculaire et Physiologique, Montigny-le-Bretonneux, France.,Co-senior authors
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Saitoh Y, Fujikake N, Okamoto Y, Popiel HA, Hatanaka Y, Ueyama M, Suzuki M, Gaumer S, Murata M, Wada K, Nagai Y. p62 plays a protective role in the autophagic degradation of polyglutamine protein oligomers in polyglutamine disease model flies. J Biol Chem 2014; 290:1442-53. [PMID: 25480790 DOI: 10.1074/jbc.m114.590281] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Oligomer formation and accumulation of pathogenic proteins are key events in the pathomechanisms of many neurodegenerative diseases, such as Alzheimer disease, ALS, and the polyglutamine (polyQ) diseases. The autophagy-lysosome degradation system may have therapeutic potential against these diseases because it can degrade even large oligomers. Although p62/sequestosome 1 plays a physiological role in selective autophagy of ubiquitinated proteins, whether p62 recognizes and degrades pathogenic proteins in neurodegenerative diseases has remained unclear. In this study, to elucidate the role of p62 in such pathogenic conditions in vivo, we used Drosophila models of neurodegenerative diseases. We found that p62 predominantly co-localizes with cytoplasmic polyQ protein aggregates in the MJDtr-Q78 polyQ disease model flies. Loss of p62 function resulted in significant exacerbation of eye degeneration in these flies. Immunohistochemical analyses revealed enhanced accumulation of cytoplasmic aggregates by p62 knockdown in the MJDtr-Q78 flies, similarly to knockdown of autophagy-related genes (Atgs). Knockdown of both p62 and Atgs did not show any additive effects in the MJDtr-Q78 flies, implying that p62 function is mediated by autophagy. Biochemical analyses showed that loss of p62 function delays the degradation of the MJDtr-Q78 protein, especially its oligomeric species. We also found that loss of p62 function exacerbates eye degeneration in another polyQ disease fly model as well as in ALS model flies. We therefore conclude that p62 plays a protective role against polyQ-induced neurodegeneration, by the autophagic degradation of polyQ protein oligomers in vivo, indicating its therapeutic potential for the polyQ diseases and possibly for other neurodegenerative diseases.
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Affiliation(s)
- Yuji Saitoh
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan, the Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8551, Japan, the Graduate School of Medical and Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba, Chiba 260-8670, Japan
| | - Nobuhiro Fujikake
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Yuma Okamoto
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - H Akiko Popiel
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Yusuke Hatanaka
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Morio Ueyama
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Mari Suzuki
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Sébastien Gaumer
- the Laboratoire de Génétique et Biologie Cellulaire, EA4589, Université de Versailles-Saint-Quentin-en-Yvelines, École Pratique des Hautes Etudes, 45 Avenue des Etats-Unis, 78035 Versailles Cedex, France, and
| | - Miho Murata
- the Department of Neurology, National Center Hospital, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-higashi, Kodaira, Tokyo 187-8551, Japan, the Graduate School of Medical and Pharmaceutical Sciences, Chiba University, 1-8-1, Inohana, Chuo-ku, Chiba, Chiba 260-8670, Japan
| | - Keiji Wada
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan
| | - Yoshitaka Nagai
- From the Department of Degenerative Neurological Diseases, National Institute of Neuroscience, National Center of Neurology and Psychiatry, 4-1-1 Ogawa-Higashi, Kodaira, Tokyo 187-8502, Japan, Core Research for Evolutional Science and Technology (CREST), Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
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10
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Colin J, Garibal J, Clavier A, Rincheval-Arnold A, Gaumer S, Mignotte B, Guénal I. The drosophila Bcl-2 family protein Debcl is targeted to the proteasome by the β-TrCP homologue slimb. Apoptosis 2014; 19:1444-56. [DOI: 10.1007/s10495-014-1034-8] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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11
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Rodríguez-Enfedaque A, Delmas E, Guillaume A, Gaumer S, Mignotte B, Vayssière JL, Renaud F. zVAD-fmk upregulates caspase-9 cleavage and activity in etoposide-induced cell death of mouse embryonic fibroblasts. Biochimica et Biophysica Acta (BBA) - Molecular Cell Research 2012; 1823:1343-52. [DOI: 10.1016/j.bbamcr.2012.05.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2011] [Revised: 05/04/2012] [Accepted: 05/10/2012] [Indexed: 11/17/2022]
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12
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Nezis IP, Simonsen A, Sagona AP, Finley K, Gaumer S, Contamine D, Rusten TE, Stenmark H, Brech A. Ref(2)P, the Drosophila melanogaster homologue of mammalian p62, is required for the formation of protein aggregates in adult brain. ACTA ACUST UNITED AC 2008; 180:1065-71. [PMID: 18347073 PMCID: PMC2290837 DOI: 10.1083/jcb.200711108] [Citation(s) in RCA: 290] [Impact Index Per Article: 18.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
p62 has been proposed to mark ubiquitinated protein bodies for autophagic degradation. We report that the Drosophila melanogaster p62 orthologue, Ref(2)P, is a regulator of protein aggregation in the adult brain. We demonstrate that Ref(2)P localizes to age-induced protein aggregates as well as to aggregates caused by reduced autophagic or proteasomal activity. A similar localization to protein aggregates is also observed in D. melanogaster models of human neurodegenerative diseases. Although atg8a autophagy mutant flies show accumulation of ubiquitin- and Ref(2)P-positive protein aggregates, this is abrogated in atg8a/ref(2)P double mutants. Both the multimerization and ubiquitin binding domains of Ref(2)P are required for aggregate formation in vivo. Our findings reveal a major role for Ref(2)P in the formation of ubiquitin-positive protein aggregates both under physiological conditions and when normal protein turnover is inhibited.
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Affiliation(s)
- Ioannis P Nezis
- Department of Biochemistry, Centre for Cancer Biomedicine, University of Oslo and Institute for Cancer Research, The Norwegian Radium Hospital, N-0310 Oslo, Norway
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13
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Lindmo K, Brech A, Finley KD, Gaumer S, Contamine D, Rusten TE, Stenmark H. The PI 3-kinase regulator Vps15 is required for autophagic clearance of protein aggregates. Autophagy 2008; 4:500-6. [PMID: 18326940 DOI: 10.4161/auto.5829] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Autophagy is involved in cellular clearance of aggregate-prone proteins, thereby having a cytoprotective function. Studies in yeast have shown that the PI 3-kinase Vps34 and its regulatory protein kinase Vps15 are important for autophagy, but the possible involvement of these proteins in autophagy in a multicellular animal has not been addressed genetically. Here, we have created a Drosophila deletion mutant of vps15 and studied its role in autophagy and aggregate clearance. Homozygous Deltavps15 Drosophila died at the early L3 larval stage. Using GFP-Atg8a as an autophagic marker, we employed fluorescence microscopy to demonstrate that fat bodies of wild type Drosophila larvae accumulated autophagic structures upon starvation whereas vps15 fat bodies showed no such response. Likewise, electron microscopy revealed starvation-induced autophagy in gut cells from wild type but not Deltavps15 larvae. Fluorescence microscopy showed that Deltavps15 mutant tissues accumulated profiles that were positive for ubiquitin and Ref(2)P, the Drosophila homolog of the sequestosome marker SQSTM1/p62. Biochemical fractionation and Western blotting showed that these structures were partially detergent insoluble, and immuno-electron microscopy further demonstrated the presence of Ref(2)P positive membrane free protein aggregates. These results provide the first genetic evidence for a function of Vps15 in autophagy in multicellular organisms and suggest that the Vps15-containing PI 3-kinase complex may play an important role in clearance of protein aggregates.
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Affiliation(s)
- Karine Lindmo
- Centre for Cancer Biomedicine, University of Oslo, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, Oslo, Norway
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14
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Carré-Mlouka A, Gaumer S, Gay P, Petitjean AM, Coulondre C, Dru P, Bras F, Dezélée S, Contamine D. Control of sigma virus multiplication by the ref(2)P gene of Drosophila melanogaster: an in vivo study of the PB1 domain of Ref(2)P. Genetics 2007; 176:409-19. [PMID: 17409092 PMCID: PMC1893033 DOI: 10.1534/genetics.106.063826] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Ref(2)P has been described as one of the Drosophila proteins that interacts with the sigma virus cycle. We generated alleles to identify critical residues involved in the restrictive (inhibiting viral multiplication) or permissive (allowing viral multiplication) character of Ref(2)P. We demonstrate that permissive alleles increase the ability of the sigma virus to infect Drosophila when compared to null alleles and we confirm that restrictive alleles decrease this capacity. Moreover, we have created alleles unfunctional in viral cycling while functional for Ref(2)P fly functions. This type of allele had never been observed before and shows that fly- and virus-related activities of Ref(2)P are separable. The viral status of Ref(2)P variants is determined by the amino-terminal PB1 domain polymorphism. In addition, an isolated PB1 domain mimics virus-related functions even if it is similar to a loss of function toward fly-related activities. The evolutionary tree of the Ref(2)P PB1 domain that we could build on the basis of the natural allele sequences is in agreement with an evolution of PB1 domain due to successive transient selection waves.
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Affiliation(s)
- A Carré-Mlouka
- Université Versailles SQY, CNRS, Laboratoire de Génétique et Biologie Cellulaire-UMR 8159, 78035 Versailles, France
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15
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Boeddrich A, Gaumer S, Haacke A, Tzvetkov N, Albrecht M, Evert BO, Müller EC, Lurz R, Breuer P, Schugardt N, Plaßmann S, Xu K, Warrick JM, Suopanki J, Wüllner U, Frank R, Hartl UF, Bonini NM, Wanker EE. An arginine/lysine-rich motif is crucial for VCP/p97-mediated modulation of ataxin-3 fibrillogenesis. EMBO J 2006; 25:1547-58. [PMID: 16525503 PMCID: PMC1440312 DOI: 10.1038/sj.emboj.7601043] [Citation(s) in RCA: 128] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2005] [Accepted: 02/21/2006] [Indexed: 11/09/2022] Open
Abstract
Arginine/lysine-rich motifs typically function as targeting signals for the translocation of proteins to the nucleus. Here, we demonstrate that such a motif consisting of four basic amino acids in the polyglutamine protein ataxin-3 (Atx-3) serves as a recognition site for the interaction with the molecular chaperone VCP. Through this interaction, VCP modulates the fibrillogenesis of pathogenic forms of Atx-3 in a concentration-dependent manner, with low concentrations of VCP stimulating fibrillogenesis and excess concentrations suppressing it. No such effect was observed with a mutant Atx-3 variant, which does not contain a functional VCP interaction motif. Strikingly, a stretch of four basic amino acids in the ubiquitin chain assembly factor E4B was also discovered to be critical for VCP binding, indicating that arginine/lysine-rich motifs might be generally utilized by VCP for the targeting of proteins. In vivo studies with Drosophila models confirmed that VCP selectively modulates aggregation and neurotoxicity induced by pathogenic Atx-3. Together, these results define the VCP-Atx-3 association as a potential target for therapeutic intervention and suggest that it might influence the progression of spinocerebellar ataxia type 3.
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Affiliation(s)
- Annett Boeddrich
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
- These two authors contributed equally to this work
| | - Sébastien Gaumer
- Department of Biology, Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA, USA
- These two authors contributed equally to this work
- Present address: Universite de Versailles Saint-Quentin-en-Yvelines, 45 avenue des Etats-Unis, F-78035 Versailles cedex, France
| | - Annette Haacke
- Max-Planck-Institute for Biochemistry, Martinsried, Germany
| | | | - Mario Albrecht
- Max-Planck-Institute for Informatics, Saarbrücken, Germany
| | - Bernd O Evert
- Department of Neurology, University of Bonn, Bonn, Germany
| | - Eva C Müller
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
| | - Rudi Lurz
- Max-Planck-Institute for Molecular Genetics, Berlin, Germany
| | - Peter Breuer
- Max-Planck-Institute for Biochemistry, Martinsried, Germany
| | - Nancy Schugardt
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
| | - Stephanie Plaßmann
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
| | - Kexiang Xu
- Department of Biology, Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - John M Warrick
- Department of Biology, Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA, USA
| | - Jaana Suopanki
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
| | | | - Ronald Frank
- Department of Chemical Biology, GBF, Braunschweig, Germany
- These are senior authors
| | - Ulrich F Hartl
- Max-Planck-Institute for Biochemistry, Martinsried, Germany
- These are senior authors
| | - Nancy M Bonini
- Department of Biology, Howard Hughes Medical Institute, University of Pennsylvania, Philadelphia, PA, USA
- These are senior authors
| | - Erich E Wanker
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Berlin, Germany
- These are senior authors
- Department of Neuroproteomics, Max Delbrueck Center for Molecular Medicine (MDC), Robert-Roessle-Straße 10, 13092 Berlin, Germany. Tel.: +49 30 9406 2157; Fax: +49 30 9406 2552; E-mail:
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16
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Brun S, Rincheval V, Gaumer S, Mignotte B, Guenal I. reaper and bax initiate two different apoptotic pathways affecting mitochondria and antagonized by bcl-2 in Drosophila. Oncogene 2002; 21:6458-70. [PMID: 12226749 DOI: 10.1038/sj.onc.1205839] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2002] [Revised: 06/07/2002] [Accepted: 06/28/2002] [Indexed: 11/08/2022]
Abstract
bcl-2 was the first regulator of apoptosis shown to be involved in oncogenesis. Subsequent studies in mammals, in the nematode and in Drosophila revealed wide evolutionary conservation of the regulation of apoptosis. Although dbok/debcl, a member of the bcl-2 gene family described in Drosophila, shows pro-apoptotic activities, no anti-apoptotic bcl-2 family gene has been studied in Drosophila. We have previously reported that the human anti-apoptotic gene bcl-2 is functional in Drosophila, suggesting that the fruit fly shares regulatory mechanisms with vertebrates and the nematode, involving anti-apoptotic members of the bcl-2 family. We now report that bcl-2 suppresses rpr-induced apoptosis in Drosophila. Additionally, we have compared features of bax- and rpr-induced apoptosis. Flow cytometry analysis of wing disc cells demonstrate that both killers trigger mitochondrial defects. Interestingly, bcl-2 suppresses both bax- and rpr-induced mitochondrial defects while the caspase-inhibitor p35 is specific to the rpr pathway. Finally, we show that the inhibition of apoptosis by bcl-2 is associated with the down-regulation of rpr expression.
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Affiliation(s)
- Sylvain Brun
- Laboratoire de Génétique et Biologie Cellulaire, CNRS UPRES-A 8087, et Laboratoire de Génétique Moléculaire et Physiologie de l'EPHE, Université de Versailles-St Quentin en Yvelines, 45 avenue des Etats-Unis, F-78035 Versailles cedex, France
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17
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18
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Abstract
Studies of apoptosis in C. elegans have allowed the identification of three genes, ced-3, ced-4 and ced-9. Their products constitute the components of an induction pathway of apoptosis conserved in the nematode and mammals. In Drosophila, homologues have been found for CED-3, CED-4 and CED-9. CED-9 belongs to the Bcl-2 family which includes negative (Bcl-2) and positive (Bax) regulators of apoptosis. The recently discovered Bcl-2 family member named Drob-1 acts as a positive regulator of cell death. To address whether a Bcl-2 anti-apoptotic pathway exists in the fly, we studied the effects of expressing the mammalian genes bcl-2 in Drosophila. In embryos, expression of bcl-2 inhibits developmental and X-ray-induced apoptosis. Expressing bcl-2 or the pro-apoptotic mammalian bax in the developing eye and wing alters these structures, bcl-2 increasing the number of cells, while bax reduces the number of cells. In addition, the functional interaction between Bcl-2 and Bax is conserved. These results indicate that factors necessary for the activity of bcl-2 and bax are present in Drosophila. Therefore, a Bcl-2 pathway for inhibition of cell death may exist in the fly.
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Affiliation(s)
- S Gaumer
- CNRS - UPRES-A 8087, Université de Versailles/Saint-Quentin, 78035 Versailles cedex, France
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19
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Fernandez-Bellot E, Guillemet E, Baudin-Baillieu A, Gaumer S, Komar AA, Cullin C. Characterization of the interaction domains of Ure2p, a prion-like protein of yeast. Biochem J 1999; 338 ( Pt 2):403-7. [PMID: 10024516 PMCID: PMC1220066] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/10/2023]
Abstract
In the yeast Saccharomyces cerevisiae, the non-Mendelian inherited genetic element [URE3] behaves as a prion. A hypothesis has been put forward which states that [URE3] arises spontaneously from its cellular isoform Ure2p (the product of the URE2 gene), and propagates through interactions of the N-terminal domain of the protein, thus leading to its aggregation and loss of function. In the present study, various N- and C-terminal deletion mutants of Ure2p were constructed and their cross-interactions were tested in vitro and in vivo using affinity binding and a two-hybrid analysis. We show that the self-interaction of the protein is mediated by at least two domains, corresponding to the first third of the protein (the so-called prion-forming domain) and the C-terminal catalytic domain.
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Affiliation(s)
- E Fernandez-Bellot
- Centre de Génétique Moléculaire du C.N.R.S., Laboratoire Propre Associé à l'Université Pierre-et-Marie-Curie, 91190 Gif-sur-Yvette, France
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20
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Abstract
Apoptosis and necrosis, two morphologically distinct forms of cell death, can be induced by common stimuli depending on the doses and the cell type. This study compares the protective effect of oncoprotein Bcl-2 and of the small stress protein Hsp27 on these two types of cell death. We use rat embryo fibroblasts conditionally immortalized by the tsA58 mutant of SV40 large T antigen as parental cells to develop cell lines carrying inducible bcl-2 or hsp27 genes. Two apoptotic stimuli were used: shift to the restrictive temperature that induced p53-mediated apoptosis and treatment with low doses of hydrogen peroxide. Necrosis was induced by high doses of hydrogen peroxide. Although Bcl-2 and Hsp27 protect these cells from necrotic death, only Bcl-2 appears capable of preventing apoptotic death. Bcl-2 protection is not mediated by a negative effect on the induction of the p53 responsive genes bax or waf1 but it slows down at least two stages of apoptosis: decrease of mitochondrial membrane potential and subsequent morphological changes. In contrast, although Hsp27 has been recently shown to inhibit apoptosis induced by various stimuli, its overexpression has no effect on apoptosis in this cell system. It should be also noticed that the apoptotic stimuli (temperature shift or hydrogen peroxide treatment) induce Hsp27, but not Bcl-2 accumulation suggesting that, in parental cells, Hsp27 might already provide some protection. However, taken together these results suggest that Hsp27, as well as Bcl-2, acts at several levels to inhibit cell death, but that their protective functions only partially overlap.
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Affiliation(s)
- I Guénal
- Centre de Génétique Moléculaire, UPR 9061 du CNRS, Gif-sur-Yvette cedex, France
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