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Boone M, Zappa F. Signaling plasticity in the integrated stress response. Front Cell Dev Biol 2023; 11:1271141. [PMID: 38143923 PMCID: PMC10740175 DOI: 10.3389/fcell.2023.1271141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 11/29/2023] [Indexed: 12/26/2023] Open
Abstract
The Integrated Stress Response (ISR) is an essential homeostatic signaling network that controls the cell's biosynthetic capacity. Four ISR sensor kinases detect multiple stressors and relay this information to downstream effectors by phosphorylating a common node: the alpha subunit of the eukaryotic initiation factor eIF2. As a result, general protein synthesis is repressed while select transcripts are preferentially translated, thus remodeling the proteome and transcriptome. Mounting evidence supports a view of the ISR as a dynamic signaling network with multiple modulators and feedback regulatory features that vary across cell and tissue types. Here, we discuss updated views on ISR sensor kinase mechanisms, how the subcellular localization of ISR components impacts signaling, and highlight ISR signaling differences across cells and tissues. Finally, we consider crosstalk between the ISR and other signaling pathways as a determinant of cell health.
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2
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Knowles AA, Campbell SG, Cross NA, Stafford P. Dysregulation of Stress-Induced Translational Control by Porphyromonas gingivalis in Host Cells. Microorganisms 2023; 11:microorganisms11030606. [PMID: 36985180 PMCID: PMC10057856 DOI: 10.3390/microorganisms11030606] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2023] [Revised: 02/15/2023] [Accepted: 02/21/2023] [Indexed: 03/04/2023] Open
Abstract
Porphyromonas gingivalis contributes to the chronic oral disease periodontitis, triggering the activation of host inflammatory responses, inducing cellular stresses such as oxidation. During stress, host cells can activate the Integrated Stress Response (ISR), a pathway which determines cellular fate, by either downregulating protein synthesis and initiating a stress–response gene expression program, or by initiating programmed cell death. Recent studies have implicated the ISR within both host antimicrobial defenses and the pathomechanism of certain microbes. In this study, using a combination of immunofluorescence confocal microscopy and immunoblotting, the molecular mechanisms by which P. gingivalis infection alters translation attenuation during oxidative stress-induced activation of the ISR in oral epithelial cells were investigated. P. gingivalis infection alone did not result in ISR activation. In contrast, infection coupled with stress caused differential stress granule formation and composition. Infection heightened stress-induced translational repression independently of core ISR mediators. Heightened translational repression during stress was observed with both P. gingivalis–conditioned media and outer membrane vesicles, implicating a secretory factor in this exacerbated translational repression. The effects of gingipain inhibitors and gingipain-deficient P. gingivalis mutants confirmed these pathogen-specific proteases as the effector of exacerbated translational repression. Gingipains are known to degrade the mammalian target of rapamycin (mTOR) and the findings of this study implicate the gingipain-mTOR axis as the effector of host translational dysregulation during stress.
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Bourke AM, Schwarz A, Schuman EM. De-centralizing the Central Dogma: mRNA translation in space and time. Mol Cell 2023; 83:452-468. [PMID: 36669490 DOI: 10.1016/j.molcel.2022.12.030] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 12/16/2022] [Accepted: 12/28/2022] [Indexed: 01/20/2023]
Abstract
As our understanding of the cell interior has grown, we have come to appreciate that most cellular operations are localized, that is, they occur at discrete and identifiable locations or domains. These cellular domains contain enzymes, machines, and other components necessary to carry out and regulate these localized operations. Here, we review these features of one such operation: the localization and translation of mRNAs within subcellular compartments observed across cell types and organisms. We describe the conceptual advantages and the "ingredients" and mechanisms of local translation. We focus on the nature and features of localized mRNAs, how they travel and get localized, and how this process is regulated. We also evaluate our current understanding of protein synthesis machines (ribosomes) and their cadre of regulatory elements, that is, the translation factors.
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Affiliation(s)
- Ashley M Bourke
- Max Planck Institute for Brain Research, Max von Laue Strasse 4, 60438 Frankfurt, Germany
| | - Andre Schwarz
- Max Planck Institute for Brain Research, Max von Laue Strasse 4, 60438 Frankfurt, Germany
| | - Erin M Schuman
- Max Planck Institute for Brain Research, Max von Laue Strasse 4, 60438 Frankfurt, Germany.
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4
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Kamble VS, Pachpor TA, Khandagale SB, Wagh VV, Khare SP. Translation initiation and dysregulation of initiation factors in rare diseases. GENE REPORTS 2022. [DOI: 10.1016/j.genrep.2022.101738] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
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5
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The role of eIF2 phosphorylation in cell and organismal physiology: new roles for well-known actors. Biochem J 2022; 479:1059-1082. [PMID: 35604373 DOI: 10.1042/bcj20220068] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 04/21/2022] [Accepted: 04/25/2022] [Indexed: 02/06/2023]
Abstract
Control of protein synthesis (mRNA translation) plays key roles in shaping the proteome and in many physiological, including homeostatic, responses. One long-known translational control mechanism involves phosphorylation of initiation factor, eIF2, which is catalysed by any one of four protein kinases, which are generally activated in response to stresses. They form a key arm of the integrated stress response (ISR). Phosphorylated eIF2 inhibits eIF2B (the protein that promotes exchange of eIF2-bound GDP for GTP) and thus impairs general protein synthesis. However, this mechanism actually promotes translation of certain mRNAs by virtue of specific features they possess. Recent work has uncovered many previously unknown features of this regulatory system. Several studies have yielded crucial insights into the structure and control of eIF2, including that eIF2B is regulated by several metabolites. Recent studies also reveal that control of eIF2 and the ISR helps determine organismal lifespan and surprising roles in sensing mitochondrial stresses and in controlling the mammalian target of rapamycin (mTOR). The latter effect involves an unexpected role for one of the eIF2 kinases, HRI. Phosphoproteomic analysis identified new substrates for another eIF2 kinase, Gcn2, which senses the availability of amino acids. Several genetic disorders arise from mutations in genes for eIF2α kinases or eIF2B (i.e. vanishing white matter disease, VWM and microcephaly, epileptic seizures, microcephaly, hypogenitalism, diabetes and obesity, MEHMO). Furthermore, the eIF2-mediated ISR plays roles in cognitive decline associated with Alzheimer's disease. New findings suggest potential therapeutic value in interfering with the ISR in certain settings, including VWM, for example by using compounds that promote eIF2B activity.
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6
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Regulation and function of elF2B in neurological and metabolic disorders. Biosci Rep 2022; 42:231311. [PMID: 35579296 PMCID: PMC9208314 DOI: 10.1042/bsr20211699] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 04/28/2022] [Accepted: 05/12/2022] [Indexed: 11/27/2022] Open
Abstract
Eukaryotic initiation factor 2B, eIF2B is a guanine nucleotide exchange, factor with a central role in coordinating the initiation of translation. During stress and disease, the activity of eIF2B is inhibited via the phosphorylation of its substrate eIF2 (p-eIF2α). A number of different kinases respond to various stresses leading to the phosphorylation of the alpha subunit of eIF2, and collectively this regulation is known as the integrated stress response, ISR. This targeting of eIF2B allows the cell to regulate protein synthesis and reprogramme gene expression to restore homeostasis. Advances within structural biology have furthered our understanding of how eIF2B interacts with eIF2 in both the productive GEF active form and the non-productive eIF2α phosphorylated form. Here, current knowledge of the role of eIF2B in the ISR is discussed within the context of normal and disease states focusing particularly on diseases such as vanishing white matter disease (VWMD) and permanent neonatal diabetes mellitus (PNDM), which are directly linked to mutations in eIF2B. The role of eIF2B in synaptic plasticity and memory formation is also discussed. In addition, the cellular localisation of eIF2B is reviewed and considered along with the role of additional in vivo eIF2B binding factors and protein modifications that may play a role in modulating eIF2B activity during health and disease.
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7
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Costei C, Barbarosie M, Bernard G, Brais B, La Piana R. Adult Hereditary White Matter Diseases With Psychiatric Presentation: Clinical Pointers and MRI Algorithm to Guide the Diagnostic Process. J Neuropsychiatry Clin Neurosci 2022; 33:180-193. [PMID: 33951919 DOI: 10.1176/appi.neuropsych.20110294] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE The investigators aimed to provide clinical and MRI guidelines for determining when genetic workup should be considered in order to exclude hereditary leukoencephalopathies in affected patients with a psychiatric presentation. METHODS A systematic literature review was conducted, and clinical cases are provided. Given the central role of MRI pattern recognition in the diagnosis of white matter disorders, the investigators adapted an MRI algorithm that guides the interpretation of MRI findings and thus directs further investigations, such as genetic testing. RESULTS Twelve genetic leukoencephalopathies that can present with psychiatric symptoms were identified. As examples of presentations that can occur in clinical practice, five clinical vignettes from patients assessed at a referral center for adult genetic leukoencephalopathies are provided. CONCLUSIONS Features such as drug-resistant symptoms, presence of long-standing somatic features, trigger events, consanguinity, and positive family history should orient the clinician toward diagnostic workup to exclude the presence of a genetic white matter disorder. The identification of MRI white matter abnormalities, especially when presenting a specific pattern of involvement, should prompt genetic testing for known forms of genetic leukoencephalopathies.
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Affiliation(s)
- Catalina Costei
- Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal (Costei, Brais, La Piana); Department of Psychiatry, McGill University (Barbarosie); Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University (Bernard); Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal (Bernard); Child Health and Human Development Program, Research Institute of the McGill University Health Center (Bernard); and Department of Diagnostic Radiology, McGill University (La Piana)
| | - Michaela Barbarosie
- Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal (Costei, Brais, La Piana); Department of Psychiatry, McGill University (Barbarosie); Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University (Bernard); Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal (Bernard); Child Health and Human Development Program, Research Institute of the McGill University Health Center (Bernard); and Department of Diagnostic Radiology, McGill University (La Piana)
| | - Geneviève Bernard
- Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal (Costei, Brais, La Piana); Department of Psychiatry, McGill University (Barbarosie); Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University (Bernard); Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal (Bernard); Child Health and Human Development Program, Research Institute of the McGill University Health Center (Bernard); and Department of Diagnostic Radiology, McGill University (La Piana)
| | - Bernard Brais
- Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal (Costei, Brais, La Piana); Department of Psychiatry, McGill University (Barbarosie); Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University (Bernard); Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal (Bernard); Child Health and Human Development Program, Research Institute of the McGill University Health Center (Bernard); and Department of Diagnostic Radiology, McGill University (La Piana)
| | - Roberta La Piana
- Department of Neurology and Neurosurgery, Montreal Neurological Institute-Hospital, McGill University, Montreal (Costei, Brais, La Piana); Department of Psychiatry, McGill University (Barbarosie); Departments of Neurology and Neurosurgery, Pediatrics and Human Genetics, McGill University (Bernard); Department of Specialized Medicine, Division of Medical Genetics, McGill University Health Center, Montreal (Bernard); Child Health and Human Development Program, Research Institute of the McGill University Health Center (Bernard); and Department of Diagnostic Radiology, McGill University (La Piana)
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8
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Norris K, Hodgson RE, Dornelles T, Allen KE, Abell BM, Ashe MP, Campbell SG. Mutational analysis of the alpha subunit of eIF2B provides insights into the role of eIF2B bodies in translational control and VWM disease. J Biol Chem 2021; 296:100207. [PMID: 33334879 PMCID: PMC7948505 DOI: 10.1074/jbc.ra120.014956] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 12/14/2020] [Accepted: 12/17/2020] [Indexed: 12/17/2022] Open
Abstract
Eukaryotic initiation factor 2B (eIF2B) serves as a vital control point within protein synthesis and regulates translation initiation in response to cellular stress. Mutations within eIF2B result in the fatal disease, leukoencephalopathy with vanishing white matter (VWM). Previous biochemical studies on VWM mutations have illustrated that changes in the activity of eIF2B poorly correlate with disease severity. This suggests that there may be additional characteristics of eIF2B contributing to VWM pathogenesis. Here, we investigated whether the localization of eIF2B to eIF2B bodies was integral for function and whether this localization could provide insight into the pathogenesis of VWM. We demonstrate that the regulatory subunit, eIF2Bα, is required for the assembly of eIF2B bodies in yeast and that loss of eIF2B bodies correlates with an inability of cells to regulate eIF2B activity. Mutational analysis of eIF2Bα showed that missense mutations that disrupt the regulation of eIF2B similarly disrupt the assembly of eIF2B bodies. In contrast, when eIF2Bα mutations that impact the catalytic activity of eIF2B were analyzed, eIF2B bodies were absent and instead eIF2B localized to small foci, termed microfoci. Fluorescence recovery after photobleaching analysis highlighted that within these microfoci, eIF2 shuttles more slowly indicating that formation of eIF2B bodies correlates with full eIF2B activity. When eIF2Bα VWM mutations were analyzed, a diverse impact on localization was observed, which did not seem to correlate with eIF2B activity. These findings provide key insights into how the eIF2B body assembles and suggest that the body is a fundamental part of the translational regulation via eIF2α phosphorylation.
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Affiliation(s)
- Karl Norris
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Rachel E Hodgson
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Tawni Dornelles
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - K Elizabeth Allen
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Ben M Abell
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK
| | - Mark P Ashe
- Division of Molecular and Cellular Function, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester, UK
| | - Susan G Campbell
- Biomolecular Sciences Research Centre, Sheffield Hallam University, Sheffield, UK.
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9
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Zyryanova AF, Kashiwagi K, Rato C, Harding HP, Crespillo-Casado A, Perera LA, Sakamoto A, Nishimoto M, Yonemochi M, Shirouzu M, Ito T, Ron D. ISRIB Blunts the Integrated Stress Response by Allosterically Antagonising the Inhibitory Effect of Phosphorylated eIF2 on eIF2B. Mol Cell 2020; 81:88-103.e6. [PMID: 33220178 PMCID: PMC7837216 DOI: 10.1016/j.molcel.2020.10.031] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 10/20/2020] [Accepted: 10/22/2020] [Indexed: 12/21/2022]
Abstract
The small molecule ISRIB antagonizes the activation of the integrated stress response (ISR) by phosphorylated translation initiation factor 2, eIF2(αP). ISRIB and eIF2(αP) bind distinct sites in their common target, eIF2B, a guanine nucleotide exchange factor for eIF2. We have found that ISRIB-mediated acceleration of eIF2B’s nucleotide exchange activity in vitro is observed preferentially in the presence of eIF2(αP) and is attenuated by mutations that desensitize eIF2B to the inhibitory effect of eIF2(αP). ISRIB’s efficacy as an ISR inhibitor in cells also depends on presence of eIF2(αP). Cryoelectron microscopy (cryo-EM) showed that engagement of both eIF2B regulatory sites by two eIF2(αP) molecules remodels both the ISRIB-binding pocket and the pockets that would engage eIF2α during active nucleotide exchange, thereby discouraging both binding events. In vitro, eIF2(αP) and ISRIB reciprocally opposed each other’s binding to eIF2B. These findings point to antagonistic allostery in ISRIB action on eIF2B, culminating in inhibition of the ISR. Mutually antagonistic binding of phosphorylated eIF2 and ISRIB to eIF2B Opposing structural rearrangement of eIF2B by binding ISRIB or phosphorylated eIF2 Phosphorylated eIF2 exposes ISRIB’s ability to enhance eIF2B activity in vitro Weak ISR-inhibitory activity of ISRIB in cells lacking phosphorylated eIF2
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Affiliation(s)
- Alisa F Zyryanova
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Kazuhiro Kashiwagi
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Claudia Rato
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Heather P Harding
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Ana Crespillo-Casado
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Luke A Perera
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK
| | - Ayako Sakamoto
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Madoka Nishimoto
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Mayumi Yonemochi
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Mikako Shirouzu
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Takuhiro Ito
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.
| | - David Ron
- Cambridge Institute for Medical Research (CIMR), University of Cambridge, Cambridge CB2 0XY, UK.
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10
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Marini G, Nüske E, Leng W, Alberti S, Pigino G. Reorganization of budding yeast cytoplasm upon energy depletion. Mol Biol Cell 2020; 31:1232-1245. [PMID: 32293990 PMCID: PMC7353153 DOI: 10.1091/mbc.e20-02-0125] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Yeast cells, when exposed to stress, can enter a protective state in which cell division, growth, and metabolism are down-regulated. They remain viable in this state until nutrients become available again. How cells enter this protective survival state and what happens at a cellular and subcellular level are largely unknown. In this study, we used electron tomography to investigate stress-induced ultrastructural changes in the cytoplasm of yeast cells. After ATP depletion, we observed significant cytosolic compaction and extensive cytoplasmic reorganization, as well as the emergence of distinct membrane-bound and membraneless organelles. Using correlative light and electron microscopy, we further demonstrated that one of these membraneless organelles was generated by the reversible polymerization of eukaryotic translation initiation factor 2B, an essential enzyme in the initiation of protein synthesis, into large bundles of filaments. The changes we observe are part of a stress-induced survival strategy, allowing yeast cells to save energy, protect proteins from degradation, and inhibit protein functionality by forming assemblies of proteins.
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Affiliation(s)
- Guendalina Marini
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Elisabeth Nüske
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Weihua Leng
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Simon Alberti
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
| | - Gaia Pigino
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden 01307, Germany
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11
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Marintchev A, Ito T. eIF2B and the Integrated Stress Response: A Structural and Mechanistic View. Biochemistry 2020; 59:1299-1308. [PMID: 32200625 DOI: 10.1021/acs.biochem.0c00132] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The eukaryotic translation initiation factor eIF2 is a GTPase, which brings the initiator Met-tRNAi to the ribosome as the eIF2-GTP·Met-tRNAi ternary complex (TC). TC regeneration is catalyzed by the guanine nucleotide exchange factor (GEF) eIF2B. eIF2 phosphorylation by several stress-induced kinases converts it into a competitive inhibitor of eIF2B. Inhibition of eIF2B activity lowers cellular TC concentrations, which in turn triggers the integrated stress response (ISR). Depending on its degree of activation and duration, the ISR protects the cell from the stress or can itself induce apoptosis. ISR dysregulation is a causative factor in the pathology of multiple neurodegenerative disorders, while ISR inhibitors are neuroprotective. The realization that eIF2B is a promising therapeutic target has triggered significant interest in its structure and its mechanisms of action and regulation. Recently, four groups published the cryo-electron microscopy structures of eIF2B with its substrate eIF2 and/or its inhibitor, phosphorylated eIF2 [eIF2(α-P)]. While all three structures of the nonproductive eIF2B·eIF2(α-P) complex are similar to each other, there is a sharp disagreement between the published structures of the productive eIF2B·eIF2 complex. One group reports a structure similar to that of the nonproductive complex, whereas two others observe a vastly different eIF2B·eIF2 complex. Here, we discuss the recent reports on the structure, function, and regulation of eIF2B; the preclinical data on the use of ISR inhibitors for the treatment of neurodegenerative disorders; and how the new structural and biochemical information can inform and influence the use of eIF2B as a therapeutic target.
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Affiliation(s)
- Assen Marintchev
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, Massachusetts 02118, United States
| | - Takuhiro Ito
- RIKEN Center for Biosystems Dynamics Research, Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
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12
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Pizzinga M, Harvey RF, Garland GD, Mordue R, Dezi V, Ramakrishna M, Sfakianos A, Monti M, Mulroney TE, Poyry T, Willis AE. The cell stress response: extreme times call for post‐transcriptional measures. WILEY INTERDISCIPLINARY REVIEWS-RNA 2019; 11:e1578. [DOI: 10.1002/wrna.1578] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 10/09/2019] [Accepted: 10/16/2019] [Indexed: 12/26/2022]
Affiliation(s)
| | | | | | - Ryan Mordue
- MRC Toxicology Unit University of Cambridge Leicester UK
| | - Veronica Dezi
- MRC Toxicology Unit University of Cambridge Leicester UK
| | | | | | - Mie Monti
- MRC Toxicology Unit University of Cambridge Leicester UK
| | | | - Tuija Poyry
- MRC Toxicology Unit University of Cambridge Leicester UK
| | - Anne E. Willis
- MRC Toxicology Unit University of Cambridge Leicester UK
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13
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Bejoy J, Yuan X, Song L, Hua T, Jeske R, Sart S, Sang QXA, Li Y. Genomics Analysis of Metabolic Pathways of Human Stem Cell-Derived Microglia-Like Cells and the Integrated Cortical Spheroids. Stem Cells Int 2019; 2019:2382534. [PMID: 31827525 PMCID: PMC6885849 DOI: 10.1155/2019/2382534] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 09/18/2019] [Accepted: 10/09/2019] [Indexed: 12/27/2022] Open
Abstract
Brain spheroids or organoids derived from human pluripotent stem cells (hiPSCs) are still not capable of completely recapitulating in vivo human brain tissue, and one of the limitations is lack of microglia. To add built-in immune function, coculture of the dorsal forebrain spheroids with isogenic microglia-like cells (D-MG) was performed in our study. The three-dimensional D-MG spheroids were analyzed for their transcriptome and compared with isogenic microglia-like cells (MG). Cortical spheroids containing microglia-like cells displayed different metabolic programming, which may affect the associated phenotype. The expression of genes related to glycolysis and hypoxia signaling was increased in cocultured D-MG spheroids, indicating the metabolic shift to aerobic glycolysis, which is in favor of M1 polarization of microglia-like cells. In addition, the metabolic pathways and the signaling pathways involved in cell proliferation, cell death, PIK3/AKT/mTOR signaling, eukaryotic initiation factor 2 pathway, and Wnt and Notch pathways were analyzed. The results demonstrate the activation of mTOR and p53 signaling, increased expression of Notch ligands, and the repression of NF-κB and canonical Wnt pathways, as well as the lower expression of cell cycle genes in the cocultured D-MG spheroids. This analysis indicates that physiological 3-D microenvironment may reshape the immunity of in vitro cortical spheroids and better recapitulate in vivo brain tissue function for disease modeling and drug screening.
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Affiliation(s)
- Julie Bejoy
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, USA
| | - Xuegang Yuan
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, USA
| | - Liqing Song
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, USA
| | - Thien Hua
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
| | - Richard Jeske
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, USA
| | - Sébastien Sart
- Hydrodynamics Laboratory (LadHyX)-Department of Mechanics, Ecole Polytechnique, CNRS-UMR7646, 91128 Palaiseau, France
| | - Qing-Xiang Amy Sang
- Department of Chemistry and Biochemistry, Florida State University, Tallahassee, Florida, USA
- Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida, USA
| | - Yan Li
- Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, FL, USA
- Institute of Molecular Biophysics, Florida State University, Tallahassee, Florida, USA
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14
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Anand AA, Walter P. Structural insights into ISRIB, a memory‐enhancing inhibitor of the integrated stress response. FEBS J 2019; 287:239-245. [DOI: 10.1111/febs.15073] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/01/2019] [Accepted: 09/20/2019] [Indexed: 12/29/2022]
Affiliation(s)
- Aditya A. Anand
- Department of Biochemistry and Biophysics University of California at San Francisco San Francisco CA USA
- Howard Hughes Medical Institute San Francisco CA USA
| | - Peter Walter
- Department of Biochemistry and Biophysics University of California at San Francisco San Francisco CA USA
- Howard Hughes Medical Institute San Francisco CA USA
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