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Nair KA, Liu B. Navigating the landscape of the unfolded protein response in CD8 + T cells. Front Immunol 2024; 15:1427859. [PMID: 39026685 PMCID: PMC11254671 DOI: 10.3389/fimmu.2024.1427859] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2024] [Accepted: 06/24/2024] [Indexed: 07/20/2024] Open
Abstract
Endoplasmic reticulum stress occurs due to large amounts of misfolded proteins, hypoxia, nutrient deprivation, and more. The unfolded protein is a complex intracellular signaling network designed to operate under this stress. Composed of three individual arms, inositol-requiring enzyme 1, protein kinase RNA-like ER kinase, and activating transcription factor-6, the unfolded protein response looks to resolve stress and return to proteostasis. The CD8+ T cell is a critical cell type for the adaptive immune system. The unfolded protein response has been shown to have a wide-ranging spectrum of effects on CD8+ T cells. CD8+ T cells undergo cellular stress during activation and due to environmental insults. However, the magnitude of the effects this response has on CD8+ T cells is still understudied. Thus, studying these pathways is important to unraveling the inner machinations of these powerful cells. In this review, we will highlight the recent literature in this field, summarize the three pathways of the unfolded protein response, and discuss their roles in CD8+ T cell biology and functionality.
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Affiliation(s)
- Keith Alan Nair
- Division of Hematology, Department of Internal Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
- The Pelotonia Institute for Immuno-Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
| | - Bei Liu
- Division of Hematology, Department of Internal Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
- The Pelotonia Institute for Immuno-Oncology, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
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2
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Posadas N, Conaco C. Gene networks governing the response of a calcareous sponge to future ocean conditions reveal lineage-specific XBP1 regulation of the unfolded protein response. Ecol Evol 2024; 14:e11652. [PMID: 38952658 PMCID: PMC11214833 DOI: 10.1002/ece3.11652] [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: 03/12/2024] [Revised: 06/12/2024] [Accepted: 06/14/2024] [Indexed: 07/03/2024] Open
Abstract
Marine sponges are predicted to be winners in the future ocean due to their exemplary adaptive capacity. However, while many sponge groups exhibit tolerance to a wide range of environmental insults, calcifying sponges may be more susceptible to thermo-acidic stress. To describe the gene regulatory networks that govern the stress response of the calcareous sponge, Leucetta chagosensis (class Calcarea, order Clathrinida), individuals were subjected to warming and acidification conditions based on the climate models for 2100. Transcriptome analysis and gene co-expression network reconstruction revealed that the unfolded protein response (UPR) was activated under thermo-acidic stress. Among the upregulated genes were two lineage-specific homologs of X-box binding protein 1 (XBP1), a transcription factor that activates the UPR. Alternative dimerization between these XBP1 gene products suggests a clathrinid-specific mechanism to reversibly sequester the transcription factor into an inactive form, enabling the rapid regulation of pathways linked to the UPR in clathrinid calcareous sponges. Our findings support the idea that transcription factor duplication events may refine evolutionarily conserved molecular pathways and contribute to ecological success.
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Affiliation(s)
- Niño Posadas
- Marine Science Institute, University of the Philippines DilimanQuezon CityPhilippines
- Present address:
Centre for Chromosome Biology, School of Biological and Chemical SciencesUniversity of GalwayGalwayIreland
| | - Cecilia Conaco
- Marine Science Institute, University of the Philippines DilimanQuezon CityPhilippines
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Dabsan S, Twito G, Biadsy S, Igbaria A. Less is better: various means to reduce protein load in the endoplasmic reticulum. FEBS J 2024. [PMID: 38865586 DOI: 10.1111/febs.17201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/08/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024]
Abstract
The endoplasmic reticulum (ER) is an important organelle that controls the intracellular and extracellular environments. The ER is responsible for folding almost one-third of the total protein population in the eukaryotic cell. Disruption of ER-protein folding is associated with numerous human diseases, including metabolic disorders, neurodegenerative diseases, and cancer. During ER perturbations, the cells deploy various mechanisms to increase the ER-folding capacity and reduce ER-protein load by minimizing the number of substrates entering the ER to regain homeostasis. These mechanisms include signaling pathways, degradation mechanisms, and other processes that mediate the reflux of ER content to the cytosol. In this review, we will discuss the recent discoveries of five different ER quality control mechanisms, including the unfolded protein response (UPR), ER-associated-degradation (ERAD), pre-emptive quality control, ER-phagy and ER to cytosol signaling (ERCYS). We will discuss the roles of these processes in decreasing ER-protein load and inter-mechanism crosstalk.
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Affiliation(s)
- Salam Dabsan
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Gal Twito
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Suma Biadsy
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
| | - Aeid Igbaria
- Department of Life Sciences, Ben-Gurion University of the Negev, Beer Sheva, Israel
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Qiao D, Xu X, Zhang Y, Yang J, Brasier AR. RSV replication modifies the XBP1s binding complex on the IRF1 upstream enhancer to potentiate the mucosal anti-viral response. Front Immunol 2023; 14:1197356. [PMID: 37564646 PMCID: PMC10411192 DOI: 10.3389/fimmu.2023.1197356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Accepted: 07/06/2023] [Indexed: 08/12/2023] Open
Abstract
Introduction The unfolded protein response (UPR) has emerged as an important signaling pathway mediating anti-viral defenses to Respiratory Syncytial Virus (RSV) infection. Earlier we found that RSV replication predominantly activates the evolutionarily conserved Inositol Requiring Enzyme 1α (IRE1α)-X-Box Binding Protein 1 spliced (XBP1s) arm of the Unfolded Protein Response (UPR) producing inflammation, metabolic adaptation and cellular plasticity, yet the mechanisms how the UPR potentiates inflammation are not well understood. Methods To understand this process better, we examined the genomic response integrating RNA-seq and Cleavage Under Targets and Release Using Nuclease (CUT&RUN) analyses. These data were integrated with an RNA-seq analysis conducted on RSV-infected small airway cells ± an IRE1α RNAse inhibitor. Results We identified RSV induced expression changes in ~3.2K genes; of these, 279 required IRE1α and were enriched in IL-10/cytokine signaling pathways. From this data set, we identify those genes directly under XBP1s control by CUT&RUN. Although XBP1s binds to ~4.2 K high-confidence genomic binding sites, surprisingly only a small subset of IL10/cytokine signaling genes are directly bound. We further apply CUT&RUN to find that RSV infection enhances XBP1s loading on 786 genomic sites enriched in AP1/Fra-1, RELA and SP1 binding sites. These control a subset of cytokine regulatory factor genes including IFN response factor 1 (IRF1), CSF2, NFKB1A and DUSP10. Focusing on the downstream role of IRF1, selective knockdown (KD) and overexpression experiments demonstrate IRF1 induction controls type I and -III interferon (IFN) and IFN-stimulated gene (ISG) expression, demonstrating that ISG are indirectly regulated by XBP1 through IRF1 transactivation. Examining the mechanism of IRF1 activation, we observe that XBP1s directly binds a 5' enhancer sequence whose XBP1s loading is increased by RSV. The functional requirement for the enhancer is demonstrated by targeting a dCas9-KRAB silencer, reducing IRF1 activation. Chromatin immunoprecipitation shows that XBP1 is required, but not sufficient, for RSV-induced recruitment of activated phospho-Ser2 Pol II to the enhancer. Discussion We conclude that XBP1s is a direct activator of a core subset of IFN and cytokine regulatory genes in response to RSV. Of these IRF1 is upstream of the type III IFN and ISG response. We find that RSV modulates the XBP1s binding complex on the IRF1 5' enhancer whose activation is required for IRF1 expression. These findings provide novel insight into how the IRE1α-XBP1s pathway potentiates airway mucosal anti-viral responses.
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Affiliation(s)
- Dianhua Qiao
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Xiaofang Xu
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
| | - Yueqing Zhang
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Jun Yang
- Department of Internal Medicine, University of Texas Medical Branch, Galveston, TX, United States
| | - Allan R. Brasier
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI, United States
- Institute for Clinical and Translational Research (ICTR), University of Wisconsin-Madison, Madison, WI, United States
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Qiao D, Skibba M, Xu X, Brasier AR. Genomic targets of the IRE1-XBP1s pathway in mediating metabolic adaptation in epithelial plasticity. Nucleic Acids Res 2023; 51:3650-3670. [PMID: 36772828 PMCID: PMC10164557 DOI: 10.1093/nar/gkad077] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 01/19/2023] [Accepted: 02/09/2023] [Indexed: 02/12/2023] Open
Abstract
Epithelial mesenchymal plasticity (EMP) is a complex cellular reprogramming event that plays a major role in tissue homeostasis. Recently we observed the unfolded protein response (UPR) triggers EMP through the inositol-requiring protein 1 (IRE1α)-X-box-binding protein 1 spliced (XBP1s) axis, enhancing glucose shunting to protein N glycosylation. To better understand the genomic targets of XBP1s, we identified its genomic targets using Cleavage Under Targets and Release Using Nuclease (CUT&RUN) of a FLAG-epitope tagged XBP1s in RSV infection. CUT&RUN identified 7086 binding sites in chromatin that were enriched in AP-1 motifs and GC-sequences. Of these binding sites, XBP1s peaks mapped to 4827 genes controlling Rho-GTPase signaling, N-linked glycosylation and ER-Golgi transport. Strikingly, XBP1s peaks were within 1 kb of transcription start sites of 2119 promoters. In addition to binding core mesenchymal transcription factors SNAI1 and ZEB1, we observed that hexosamine biosynthetic pathway (HBP) enzymes were induced and contained proximal XBP1s peaks. We demonstrate that IRE1α -XBP1s signaling is necessary and sufficient to activate core enzymes by recruiting elongation-competent phospho-Ser2 CTD modified RNA Pol II. We conclude that the IRE1α-XBP1s pathway coordinately regulates mesenchymal transcription factors and hexosamine biosynthesis in EMP by a mechanism involving recruitment of activated pSer2-Pol II to GC-rich promoters.
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Affiliation(s)
- Dianhua Qiao
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI 53705, USA
| | - Melissa Skibba
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI 53705, USA
| | - Xiaofang Xu
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI 53705, USA
| | - Allan R Brasier
- Department of Medicine, University of Wisconsin-Madison School of Medicine and Public Health (SMPH), Madison, WI 53705, USA
- Institute for Clinical and Translational Research (ICTR), University of Wisconsin-Madison, Madison, WI 1053705, USA
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Krappitz M, Bhardwaj R, Dong K, Staudner T, Yilmaz DE, Pioppini C, Westergerling P, Ruemmele D, Hollmann T, Nguyen TA, Cai Y, Gallagher AR, Somlo S, Fedeles S. XBP1 Activation Reduces Severity of Polycystic Kidney Disease due to a Nontruncating Polycystin-1 Mutation in Mice. J Am Soc Nephrol 2023; 34:110-121. [PMID: 36270750 PMCID: PMC10101557 DOI: 10.1681/asn.2021091180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Accepted: 09/21/2022] [Indexed: 11/07/2022] Open
Abstract
BACKGROUND Autosomal dominant polycystic kidney disease (ADPKD) is caused by mutations in Pkd1 and Pkd2. They encode the polytopic integral membrane proteins polycystin-1 (PC1) and polycystin-2 (PC2), respectively, which are expressed on primary cilia. Formation of kidney cysts in ADPKD starts when a somatic second hit mechanism inactivates the wild-type Pkd allele. Approximately one quarter of families with ADPDK due to Pkd1 have germline nonsynonymous amino acid substitution (missense) mutations. A subset of these mutations is hypomorphic, retaining some residual PC1 function. Previous studies have shown that the highly conserved Ire1 α -XBP1 pathway of the unfolded protein response can modulate levels of functional PC1 in the presence of mutations in genes required for post-translational maturation of integral membrane proteins. We examine how activity of the endoplasmic reticulum chaperone-inducing transcription factor XBP1 affects ADPKD in a murine model with missense Pkd1 . METHODS We engineered a Pkd1 REJ domain missense murine model, Pkd1 R2216W , on the basis of the orthologous human hypomorphic allele Pkd1 R2220W , and examined the effects of transgenic activation of XBP1 on ADPKD progression. RESULTS Expression of active XBP1 in cultured cells bearing PC1 R2216W mutations increased levels and ciliary trafficking of PC1 R2216W . Mice homozygous for Pkd1 R2216W or heterozygous for Pkd1 R2216Win trans with a conditional Pkd1 fl allele exhibit severe ADPKD following inactivation in neonates or adults. Transgenic expression of spliced XBP1 in tubule segments destined to form cysts reduced cell proliferation and improved Pkd progression, according to structural and functional parameters. CONCLUSIONS Modulating ER chaperone function through XBP1 activity improved Pkd in a murine model of PC1, suggesting therapeutic targeting of hypomorphic mutations.
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Affiliation(s)
- Matteus Krappitz
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
- Department of Nephrology and Medical Intensive Care, Charité—Universitätsmedizin Berlin, Berlin, Germany
- BIH Biomedical Innovation Academy, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Rishi Bhardwaj
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Ke Dong
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Tobias Staudner
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Duygu Elif Yilmaz
- Department of Nephrology and Medical Intensive Care, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Carlotta Pioppini
- Department of Nephrology and Medical Intensive Care, Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Parisa Westergerling
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - David Ruemmele
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Till Hollmann
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Thuy Anh Nguyen
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Yiqiang Cai
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Anna-Rachel Gallagher
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Stefan Somlo
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
| | - Sorin Fedeles
- Department of Internal Medicine, Section of Nephrology, Yale School of Medicine, New Haven, Connecticut
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Ma W, Zhu L, Song S, Liu B, Gu J. Identification and Validation of Glycosyltransferases Correlated with Cuproptosis as a Prognostic Model for Colon Adenocarcinoma. Cells 2022; 11:cells11233728. [PMID: 36496988 PMCID: PMC9737711 DOI: 10.3390/cells11233728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Revised: 11/14/2022] [Accepted: 11/18/2022] [Indexed: 11/24/2022] Open
Abstract
Cuproptosis is a newly defined programmed cell death pattern and is believed to play an important role in tumorigenesis and progression. In addition, many studies have shown that glycosylation modification is of vital importance in tumor progression. However, it remains unclear whether glycosyltransferases, the most critical enzymes involved in glycosylation modification, are associated with cuproptosis. In this study, we used bioinformatic methods to construct a signature of cuproptosis-related glycosyltransferases to predict the prognosis of colon adenocarcinoma patients. We found that cuproptosis was highly correlated with four glycosyltransferases in COAD, and our model predicted the prognosis of COAD patients. Further analysis of related functions revealed the possibility that cuproptosis-related glycosyltransferase Exostosin-like 2 (EXTL2) participated in tumor immunity.
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Affiliation(s)
| | | | | | - Bo Liu
- Correspondence: (S.S.); (B.L.)
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Peng J, Qin C, Ramatchandirin B, Pearah A, Guo S, Hussain M, Yu L, Wondisford FE, He L. Activation of the canonical ER Stress IRE1-XBP1 Pathway by Insulin Regulates Glucose and Lipid Metabolism. J Biol Chem 2022; 298:102283. [PMID: 35863429 PMCID: PMC9396404 DOI: 10.1016/j.jbc.2022.102283] [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: 05/06/2022] [Revised: 07/06/2022] [Accepted: 07/08/2022] [Indexed: 11/18/2022] Open
Abstract
Knockout of the transcription factor X-box binding protein (XBP1) is known to decrease liver glucose production and lipogenesis. However, whether insulin can regulate gluconeogenesis and lipogenesis through XBP1 and how insulin activates the inositol-requiring enzyme-XBP1 ER stress pathway remains unexplored. Here, we report that in the fed state, insulin-activated kinase AKT directly phosphorylates inositol-requiring enzyme 1 at S724, which in turn mediates the splicing of XBP1u mRNA, thus favoring the generation of the spliced form, XBP1s, in the liver of mice. Subsequently, XBP1s stimulate the expression of lipogenic genes and upregulates liver lipogenesis as previously reported. Intriguingly, we find that fasting leads to an increase in XBP1u along with a drastic decrease in XBP1s in the liver of mice, and XBP1u, not XBP1s, significantly increases PKA-stimulated CRE reporter activity in cultured hepatocytes. Furthermore, we demonstrate that overexpression of XBP1u significantly increases cAMP-stimulated expression of rate-limiting gluconeogenic genes, G6pc and Pck1, and glucose production in primary hepatocytes. Reexpression of XBP1u in the liver of mice with XBP1 depletion significantly increases fasting blood glucose levels and gluconeogenic gene expression. These data support an important role of XBP1u in upregulating gluconeogenesis in the fasted state. Taken together, we reveal that insulin signaling via AKT controls the expression of XBP1 isoforms and that XBP1u and XBP1s function in different nutritional states to regulate liver gluconeogenesis and lipogenesis, respectively.
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Affiliation(s)
- Jinghua Peng
- Departments of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Caolitao Qin
- Departments of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | | | - Alexia Pearah
- Departments of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
| | - Shaodong Guo
- Department of Nutrition, Texas A&M University, TX 77843
| | - Mehboob Hussain
- Division of Metabolism, Endocrinology and Diabetes, University of Michigan Medical School, Ann Arbor, Michigan 48105
| | - Liqing Yu
- Division of Metabolism, Endocrinology and Nutrition, University of Maryland School of Medicine, Baltimore, MD 21201
| | - Fredric E Wondisford
- Department of Medicine, Rutgers-Robert Wood Johnson Medical School, New Brunswick, NJ 08901
| | - Ling He
- Departments of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA; Departments of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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D'Amico D, Biondi O, Januel C, Bezier C, Sapaly D, Clerc Z, Khoury ME, Sundaram VK, Houdebine L, Josse T, Gaspera BD, Martinat C, Massaad C, Weill L, Charbonnier F. Activating ATF6 in Spinal Muscular Atrophy promotes SMN expression and motor neuron survival through the IRE1α-XBP1 pathway. Neuropathol Appl Neurobiol 2022; 48:e12816. [PMID: 35338505 DOI: 10.1111/nan.12816] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 03/15/2022] [Accepted: 03/19/2022] [Indexed: 11/27/2022]
Abstract
AIM Spinal Muscular Atrophy (SMA) is a neuromuscular disease caused by Survival of Motor Neuron (SMN) deficiency that induces motor neuron (MN) degeneration and severe muscular atrophy. Gene therapies that increase SMN have proven their efficacy but not for all patients. Here, we explored the Unfolded Protein Response (UPR) status in SMA pathology and explored whether UPR modulation could be beneficial for SMA patients. METHODS We analysed the expression and activation of key UPR proteins by RT-qPCR and by western blots in SMA patient iPSC-derived MNs and one SMA cell line in which SMN expression was re-established (rescue). We complemented this approach by using myoblast and fibroblast SMA patient cells and SMA mouse models of varying severities. Finally, we tested in vitro and in vivo the effect of IRE1α/XBP1 pathway restoration on SMN expression and subsequent neuroprotection. RESULTS We report that the IRE1α/XBP1 branch of the unfolded protein response is disrupted in SMA, with a depletion of XBP1s irrespective of IRE1α activation pattern. The overexpression of XBP1s in SMA fibroblasts proved to transcriptionally enhance SMN expression. Importantly, rebalancing XBP1s expression in severe SMA-like mice, induced SMN expression and spinal MN protection. CONCLUSIONS We have identified XBP1s depletion as a contributing factor in SMA pathogenesis, and the modulation of this transcription factor proves to be a plausible therapeutic avenue in the context of pharmacological interventions for patients.
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Affiliation(s)
- Domenico D'Amico
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | - Olivier Biondi
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | - Camille Januel
- Université d'Evry-Val-d'Essonne & Inserm UMR 861, I-STEM, AFM, Corbeil-Essonne, France
| | - Cynthia Bezier
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France.,Biophytis, Sorbonne Université, Paris Cedex 05, France
| | - Delphine Sapaly
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | - Zoé Clerc
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | | | | | - Léo Houdebine
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | - Thibaut Josse
- Université de Tour &CNRS UMR 7261, Institut de Recherche sur la Biologie de l'Insecte, Tours, France
| | | | - Cécile Martinat
- Université d'Evry-Val-d'Essonne & Inserm UMR 861, I-STEM, AFM, Corbeil-Essonne, France
| | - Charbel Massaad
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
| | - Laure Weill
- Université Paris cité & Inserm UMR_S1124, Paris Cedex 06, France
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10
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Spliced or Unspliced, That Is the Question: The Biological Roles of XBP1 Isoforms in Pathophysiology. Int J Mol Sci 2022; 23:ijms23052746. [PMID: 35269888 PMCID: PMC8910952 DOI: 10.3390/ijms23052746] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 02/27/2022] [Accepted: 02/27/2022] [Indexed: 01/27/2023] Open
Abstract
X-box binding protein 1 (XBP1) is a member of the CREB/ATF basic region leucine zipper family transcribed as the unspliced isoform (XBP1-u), which, upon exposure to endoplasmic reticulum stress, is spliced into its spliced isoform (XBP1-s). XBP1-s interacts with the cAMP response element of major histocompatibility complex class II gene and plays critical role in unfolded protein response (UPR) by regulating the transcriptional activity of genes involved in UPR. XBP1-s is also involved in other physiological pathways, including lipid metabolism, insulin metabolism, and differentiation of immune cells. Its aberrant expression is closely related to inflammation, neurodegenerative disease, viral infection, and is crucial for promoting tumor progression and drug resistance. Meanwhile, recent studies reported that the function of XBP1-u has been underestimated, as it is not merely a precursor of XBP1-s. Instead, XBP-1u is a critical factor involved in various biological pathways including autophagy and tumorigenesis through post-translational regulation. Herein, we summarize recent research on the biological functions of both XBP1-u and XBP1-s, as well as their relation to diseases.
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11
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Wang T, Zhou J, Zhang X, Wu Y, Jin K, Wang Y, Xu R, Yang G, Li W, Jiao L. X-box Binding Protein 1: An Adaptor in the Pathogenesis of Atherosclerosis. Aging Dis 2022; 14:350-369. [PMID: 37008067 PMCID: PMC10017146 DOI: 10.14336/ad.2022.0824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Accepted: 08/24/2022] [Indexed: 11/18/2022] Open
Abstract
Atherosclerosis (AS), the formation of fibrofatty lesions in the vessel wall, is the primary cause of heart disease and stroke and is closely associated with aging. Disrupted metabolic homeostasis is a primary feature of AS and leads to endoplasmic reticulum (ER) stress, which is an abnormal accumulation of unfolded proteins. By orchestrating signaling cascades of the unfolded protein response (UPR), ER stress functions as a double-edged sword in AS, where adaptive UPR triggers synthetic metabolic processes to restore homeostasis, whereas the maladaptive response programs the cell to the apoptotic pathway. However, little is known regarding their precise coordination. Herein, an advanced understanding of the role of UPR in the pathological process of AS is reviewed. In particular, we focused on a critical mediator of the UPR, X-box binding protein 1 (XBP1), and its important role in balancing adaptive and maladaptive responses. The XBP1 mRNA is processed from the unspliced isoform (XBP1u) to the spliced isoform of XBP1 (XBP1s). Compared with XBP1u, XBP1s predominantly functions downstream of inositol-requiring enzyme-1α (IRE1α) and transcript genes involved in protein quality control, inflammation, lipid metabolism, carbohydrate metabolism, and calcification, which are critical for the pathogenesis of AS. Thus, the IRE1α/XBP1 axis is a promising pharmaceutical candidate against AS.
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Affiliation(s)
- Tao Wang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.
- China International Neuroscience Institute (China-INI), Beijing, China.
| | - Jia Zhou
- Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
| | - Xiao Zhang
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.
- China International Neuroscience Institute (China-INI), Beijing, China.
| | - Yujie Wu
- Laboratory of Computational Biology and Machine Intelligence, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
| | - Kehan Jin
- Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing, China.
| | - Yilin Wang
- Institute of Cerebrovascular Disease Research and Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China.
| | - Ran Xu
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.
- China International Neuroscience Institute (China-INI), Beijing, China.
| | - Ge Yang
- Laboratory of Computational Biology and Machine Intelligence, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
- School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China.
- Correspondence should be addressed to: Dr. Ge Yang, Chinese Academy of Sciences, Beijing, China. , Dr. Wenjing Li, Chinese Academy of Sciences, Beijing, China. ; Dr. Liqun Jiao, Xuanwu Hospital, Capital Medical University, Beijing, China. .
| | - Wenjing Li
- Laboratory of Computational Biology and Machine Intelligence, National Laboratory of Pattern Recognition, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
- School of Artificial Intelligence, University of Chinese Academy of Sciences, Beijing, China.
- Correspondence should be addressed to: Dr. Ge Yang, Chinese Academy of Sciences, Beijing, China. , Dr. Wenjing Li, Chinese Academy of Sciences, Beijing, China. ; Dr. Liqun Jiao, Xuanwu Hospital, Capital Medical University, Beijing, China. .
| | - Liqun Jiao
- Department of Neurosurgery, Xuanwu Hospital, Capital Medical University, Beijing, China.
- China International Neuroscience Institute (China-INI), Beijing, China.
- Department of Interventional Radiology, Xuanwu Hospital, Capital Medical University, Beijing, China.
- Correspondence should be addressed to: Dr. Ge Yang, Chinese Academy of Sciences, Beijing, China. , Dr. Wenjing Li, Chinese Academy of Sciences, Beijing, China. ; Dr. Liqun Jiao, Xuanwu Hospital, Capital Medical University, Beijing, China. .
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12
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Park SM, Kang TI, So JS. Roles of XBP1s in Transcriptional Regulation of Target Genes. Biomedicines 2021; 9:biomedicines9070791. [PMID: 34356855 PMCID: PMC8301375 DOI: 10.3390/biomedicines9070791] [Citation(s) in RCA: 89] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Revised: 07/03/2021] [Accepted: 07/05/2021] [Indexed: 12/17/2022] Open
Abstract
The spliced form of X-box binding protein 1 (XBP1s) is an active transcription factor that plays a vital role in the unfolded protein response (UPR). Under endoplasmic reticulum (ER) stress, unspliced Xbp1 mRNA is cleaved by the activated stress sensor IRE1α and converted to the mature form encoding spliced XBP1 (XBP1s). Translated XBP1s migrates to the nucleus and regulates the transcriptional programs of UPR target genes encoding ER molecular chaperones, folding enzymes, and ER-associated protein degradation (ERAD) components to decrease ER stress. Moreover, studies have shown that XBP1s regulates the transcription of diverse genes that are involved in lipid and glucose metabolism and immune responses. Therefore, XBP1s has been considered an important therapeutic target in studying various diseases, including cancer, diabetes, and autoimmune and inflammatory diseases. XBP1s is involved in several unique mechanisms to regulate the transcription of different target genes by interacting with other proteins to modulate their activity. Although recent studies discovered numerous target genes of XBP1s via genome-wide analyses, how XBP1s regulates their transcription remains unclear. This review discusses the roles of XBP1s in target genes transcriptional regulation. More in-depth knowledge of XBP1s target genes and transcriptional regulatory mechanisms in the future will help develop new therapeutic targets for each disease.
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13
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Xu W, Wang C, Hua J. X-box binding protein 1 (XBP1) function in diseases. Cell Biol Int 2020; 45:731-739. [PMID: 33325615 DOI: 10.1002/cbin.11533] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 11/12/2020] [Accepted: 12/13/2020] [Indexed: 12/15/2022]
Abstract
The accumulation of unfolded or misfolded proteins in the endoplasmic reticulum (ER) causes endoplasmic reticulum stress (ERS), which is characteristic of cells with high levels of secretory activity and is involved in a variety of diseases. In response to ERS, cells initiate an adaptive process named the unfolding protein response (UPR) to maintain intracellular homeostasis and survival. However, long term and unresolved ERS can also induce apoptosis. As the most conserved signaling branch of UPR, the IRE1-XBP1 pathway plays an important role in both physiological and pathological states, and its activity has a profound impact on disease progression and prognosis. Here, the latest research progress of IRE1-XBP1 pathway in cancer, metabolic diseases, and other diseases was briefly introduced, and the relationship between several diseases and this pathway was analyzed. Besides, the new understanding and prospect of IRE1-XBP1 pathway regulating male reproduction were reviewed.
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Affiliation(s)
- Wenjing Xu
- Shaanxi Centre of Stem Cells Engineering & Technology, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
| | - Congrong Wang
- Translational Medical Center for Stem Cell Therapy, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, China
| | - Jinlian Hua
- Shaanxi Centre of Stem Cells Engineering & Technology, College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi, China
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14
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Özbey NP, Imanikia S, Krueger C, Hardege I, Morud J, Sheng M, Schafer WR, Casanueva MO, Taylor RC. Tyramine Acts Downstream of Neuronal XBP-1s to Coordinate Inter-tissue UPR ER Activation and Behavior in C. elegans. Dev Cell 2020; 55:754-770.e6. [PMID: 33232669 PMCID: PMC7758879 DOI: 10.1016/j.devcel.2020.10.024] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2020] [Revised: 07/17/2020] [Accepted: 10/30/2020] [Indexed: 12/28/2022]
Abstract
In C. elegans, expression of the UPRER transcription factor xbp-1s in neurons cell non-autonomously activates the UPRER in the intestine, leading to enhanced proteostasis and lifespan. To better understand this signaling pathway, we isolated neurons from animals expressing neuronal xbp-1s for transcriptomic analysis, revealing a striking remodeling of transcripts involved in neuronal signaling. We then identified signaling molecules required for cell non-autonomous intestinal UPRER activation, including the biogenic amine tyramine. Expression of xbp-1s in just two pairs of neurons that synthesize tyramine, the RIM and RIC interneurons, induced intestinal UPRER activation and extended longevity, and exposure to stress led to splicing and activation of xbp-1 in these neurons. In addition, we found that neuronal xbp-1s modulates feeding behavior and reproduction, dependent upon tyramine synthesis. XBP-1s therefore remodels neuronal signaling to coordinately modulate intestinal physiology and stress-responsive behavior, functioning as a global regulator of organismal responses to stress.
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Affiliation(s)
- Neşem P Özbey
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Soudabeh Imanikia
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Christel Krueger
- Epigenetics Programme, The Babraham Institute, Babraham CB22 3AT, UK
| | - Iris Hardege
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Julia Morud
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - Ming Sheng
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | - William R Schafer
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK
| | | | - Rebecca C Taylor
- Neurobiology Division, MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK.
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15
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Xia X. Beyond Trees: Regulons and Regulatory Motif Characterization. Genes (Basel) 2020; 11:genes11090995. [PMID: 32854400 PMCID: PMC7564462 DOI: 10.3390/genes11090995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2020] [Revised: 08/13/2020] [Accepted: 08/24/2020] [Indexed: 12/14/2022] Open
Abstract
Trees and their seeds regulate their germination, growth, and reproduction in response to environmental stimuli. These stimuli, through signal transduction, trigger transcription factors that alter the expression of various genes leading to the unfolding of the genetic program. A regulon is conceptually defined as a set of target genes regulated by a transcription factor by physically binding to regulatory motifs to accomplish a specific biological function, such as the CO-FT regulon for flowering timing and fall growth cessation in trees. Only with a clear characterization of regulatory motifs, can candidate target genes be experimentally validated, but motif characterization represents the weakest feature of regulon research, especially in tree genetics. I review here relevant experimental and bioinformatics approaches in characterizing transcription factors and their binding sites, outline problems in tree regulon research, and demonstrate how transcription factor databases can be effectively used to aid the characterization of tree regulons.
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Affiliation(s)
- Xuhua Xia
- Department of Biology, University of Ottawa, Ottawa, ON K1N 6N5, Canada;
- Ottawa Institute of Systems Biology, Ottawa, ON K1H 8M5, Canada
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16
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Chopra S, Giovanelli P, Alvarado-Vazquez PA, Alonso S, Song M, Sandoval TA, Chae CS, Tan C, Fonseca MM, Gutierrez S, Jimenez L, Subbaramaiah K, Iwawaki T, Kingsley PJ, Marnett LJ, Kossenkov AV, Crespo MS, Dannenberg AJ, Glimcher LH, Romero-Sandoval EA, Cubillos-Ruiz JR. IRE1α-XBP1 signaling in leukocytes controls prostaglandin biosynthesis and pain. Science 2020; 365:365/6450/eaau6499. [PMID: 31320508 DOI: 10.1126/science.aau6499] [Citation(s) in RCA: 86] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2018] [Revised: 03/27/2019] [Accepted: 06/10/2019] [Indexed: 12/28/2022]
Abstract
Inositol-requiring enzyme 1[α] (IRE1[α])-X-box binding protein spliced (XBP1) signaling maintains endoplasmic reticulum (ER) homeostasis while controlling immunometabolic processes. Yet, the physiological consequences of IRE1α-XBP1 activation in leukocytes remain unexplored. We found that induction of prostaglandin-endoperoxide synthase 2 (Ptgs2/Cox-2) and prostaglandin E synthase (Ptges/mPGES-1) was compromised in IRE1α-deficient myeloid cells undergoing ER stress or stimulated through pattern recognition receptors. Inducible biosynthesis of prostaglandins, including the pro-algesic mediator prostaglandin E2 (PGE2), was decreased in myeloid cells that lack IRE1α or XBP1 but not other ER stress sensors. Functional XBP1 transactivated the human PTGS2 and PTGES genes to enable optimal PGE2 production. Mice that lack IRE1α-XBP1 in leukocytes, or that were treated with IRE1α inhibitors, demonstrated reduced pain behaviors in PGE2-dependent models of pain. Thus, IRE1α-XBP1 is a mediator of prostaglandin biosynthesis and a potential target to control pain.
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Affiliation(s)
- Sahil Chopra
- Weill Cornell Graduate School of Medical Sciences, Cornell University. New York, NY 10065, USA.,Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Paolo Giovanelli
- Weill Cornell Graduate School of Medical Sciences, Cornell University. New York, NY 10065, USA.,Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Perla Abigail Alvarado-Vazquez
- Department of Anesthesiology, Pain Mechanisms Laboratory, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Sara Alonso
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | - Minkyung Song
- Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Tito A Sandoval
- Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Chang-Suk Chae
- Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Chen Tan
- Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
| | - Miriam M Fonseca
- Department of Anesthesiology, Pain Mechanisms Laboratory, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Silvia Gutierrez
- Department of Anesthesiology, Pain Mechanisms Laboratory, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA
| | - Leandro Jimenez
- Instituto Ludwig de Pesquisa Sobre o Câncer, São Paulo, Brazil.,Hospital Sírio-Libanês, São Paulo, Brazil
| | | | - Takao Iwawaki
- Division of Cell Medicine, Medical Research Institute, Kazanawa Medical University, Ishikawa, Japan
| | - Philip J Kingsley
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA
| | - Lawrence J Marnett
- Department of Biochemistry, Vanderbilt University, Nashville, TN 37232, USA.,A. B. Hancock Jr. Memorial Laboratory for Cancer Research, Departments of Biochemistry, Chemistry and Pharmacology, Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37232, USA
| | - Andrew V Kossenkov
- Center for Systems and Computational Biology, The Wistar Institute, Philadelphia, PA 19104, USA
| | - Mariano Sanchez Crespo
- Instituto de Biología y Genética Molecular, CSIC-Universidad de Valladolid, Valladolid, Spain
| | | | - Laurie H Glimcher
- Department of Medicine, Harvard Medical School and Brigham and Women's Hospital, Boston, MA 02115, USA. .,Department of Cancer Immunology and Virology, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02215, USA
| | - E Alfonso Romero-Sandoval
- Department of Anesthesiology, Pain Mechanisms Laboratory, Wake Forest University School of Medicine, Winston-Salem, NC 27157, USA.
| | - Juan R Cubillos-Ruiz
- Weill Cornell Graduate School of Medical Sciences, Cornell University. New York, NY 10065, USA. .,Department of Obstetrics and Gynecology, Weill Cornell Medicine. New York, NY 10065, USA.,Sandra and Edward Meyer Cancer Center, Weill Cornell Medicine, New York, NY 10065, USA
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17
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Wang V, Davis DA, Deleage C, Brands C, Choi HS, Haque M, Yarchoan R. Induction of Kaposi's Sarcoma-Associated Herpesvirus-Encoded Thymidine Kinase (ORF21) by X-Box Binding Protein 1. J Virol 2020; 94:e01555-19. [PMID: 31801863 PMCID: PMC7022350 DOI: 10.1128/jvi.01555-19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Accepted: 11/26/2019] [Indexed: 12/11/2022] Open
Abstract
Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent for Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and multicentric Castleman disease (MCD). Like other herpesviruses, it has latent and lytic repertoires. However, there is evidence that some lytic genes can be directly activated by certain cellular factors. Cells undergoing endoplasmic reticulum stress express spliced X-box binding protein 1 (XBP-1s). XBP-1s is also present in large amounts in germinal center B cells. XBP-1s can activate the KSHV replication and transcription activator (RTA) and lytic replication. It can also directly activate KSHV-encoded viral interleukin-6 (vIL-6) and, thus, contribute to the pathogenesis of KSHV MCD. KSHV thymidine kinase (TK), the ORF21 gene product, can enhance the production of dTTP and is important for lytic replication. It can also phosphorylate zidovudine and ganciclovir to toxic moieties, enabling treatment of KSHV-MCD with these drugs. We show here that XBP-1s can directly activate ORF21 and that this activation is mediated primarily through two XBP-response elements (XRE) on the ORF21 promoter region. Deletion or mutation of these elements eliminated XBP-1s-induced upregulation of the promoter, and chromatin immunoprecipitation studies provide evidence that XBP-1s can bind to both XREs. Exposure of PEL cells to a chemical inducer of XBP-1s can induce ORF21 within 4 hours, and ORF21 expression in the lymph nodes of patients with KSHV-MCD is predominantly found in cells with XBP-1. Thus, XBP-1s may directly upregulate KSHV ORF21 and, thus, contribute to the pathogenesis of KSHV-MCD and the activity of zidovudine and valganciclovir in this disease.IMPORTANCE Spliced X-box binding protein 1 (XBP-1s), part of the unfolded protein response and expressed in developing germinal center B cells, can induce Kaposi's sarcoma-associated herpesvirus (KSHV) lytic replication and directly activate viral interleukin-6 (vIL-6). We show here that XBP-1s can also directly activate KSHV ORF21, a lytic gene. ORF21 encodes KSHV thymidine kinase (TK), which increases the pool of dTTP for viral replication and enhances lytic replication. Direct activation of ORF21 by XBP-1s can enhance viral replication in germinal center B cells and contribute to the pathogenesis of KSHV multicentric Castleman disease (MCD). KSHV-MCD is characterized by systemic inflammation caused, in part, by lytic replication and overproduction of KSHV vIL-6 in XBP-1s-expressing lymph node plasmablasts. KSHV thymidine kinase can phosphorylate zidovudine and ganciclovir to toxic moieties, and direct activation of ORF21 by XBP-1s may also help explain the effectiveness of zidovudine and valganciclovir in the treatment of KSHV-MCD.
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Affiliation(s)
- Victoria Wang
- HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - David A Davis
- HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Claire Deleage
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Catherine Brands
- AIDS and Cancer Virus Program, Frederick National Laboratory for Cancer Research, National Cancer Institute, Frederick, Maryland, USA
| | - Hong S Choi
- HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Muzammel Haque
- HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
| | - Robert Yarchoan
- HIV and AIDS Malignancy Branch, Center for Cancer Research, National Cancer Institute, Bethesda, Maryland, USA
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18
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The IRE1 endoplasmic reticulum stress sensor activates natural killer cell immunity in part by regulating c-Myc. Nat Immunol 2019; 20:865-878. [PMID: 31086333 PMCID: PMC6588410 DOI: 10.1038/s41590-019-0388-z] [Citation(s) in RCA: 105] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 03/29/2019] [Indexed: 01/04/2023]
Abstract
Natural killer (NK) cells are critical mediators of host immunity to pathogens. Here, we demonstrate that the endoplasmic reticulum stress sensor inositol-requiring enzyme 1 (IRE1α) and its substrate transcription factor X-box-binding protein 1 (XBP1) drive NK cell responses against viral infection and tumors in vivo. IRE1α-XBP1 were essential for expansion of activated mouse and human NK cells and are situated downstream of the mammalian target of rapamycin signaling pathway. Transcriptome and chromatin immunoprecipitation analysis revealed c-Myc as a new and direct downstream target of XBP1 for regulation of NK cell proliferation. Genetic ablation or pharmaceutical blockade of IRE1α downregulated c-Myc, and NK cells with c-Myc haploinsufficency phenocopied IRE1α-XBP1 deficiency. c-Myc overexpression largely rescued the proliferation defect in IRE1α-/- NK cells. Like c-Myc, IRE1α-XBP1 also promotes oxidative phosphorylation in NK cells. Overall, our study identifies a IRE1α-XBP1-cMyc axis in NK cell immunity, providing insight into host protection against infection and cancer.
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19
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Shi W, Chen Z, Li L, Liu H, Zhang R, Cheng Q, Xu D, Wu L. Unravel the molecular mechanism of XBP1 in regulating the biology of cancer cells. J Cancer 2019; 10:2035-2046. [PMID: 31205564 PMCID: PMC6548171 DOI: 10.7150/jca.29421] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Accepted: 04/02/2019] [Indexed: 02/07/2023] Open
Abstract
Cancer cells are usually exposed to stressful environments, such as hypoxia, nutrient deprivation, and other metabolic dysfunctional regulation, leading to continuous endoplasmic reticulum (ER) stress. As the most conserved branch among the three un-folded protein response (UPR) pathways, Inositol-requiring enzyme 1α (IRE1α)-X-box-binding protein 1 (XBP1) signaling has been implicated in cancer development and progression. Active XBP1 with transactivation domain functions as a transcription factor to regulate the expression of downstream target genes, including many oncogenic factors. The regulatory activity of XBP1 in cell proliferation, apoptosis, metastasis, and drug resistance promotes cell survival, leading to tumorigenesis and tumor progression. In addition, the XBP1 peptides-based vaccination and/or combination with immune-modulatory drug administration have been developed for effective management for several cancers. Potentially, XBP1 is the biomarker of cancer development and progression and the strategy for clinical cancer management.
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Affiliation(s)
- Weimei Shi
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Zhixi Chen
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Linfu Li
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Hai Liu
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Rui Zhang
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Qilai Cheng
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
| | - Daohua Xu
- Department of Pharmacology, Guangdong Medical University, Dongguan China, 523808
| | - Longhuo Wu
- College of Pharmacy, Gannan Medical University, Ganzhou China, 341000
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20
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Wang Y, Zhang Y, Yi P, Dong W, Nalin AP, Zhang J, Zhu Z, Chen L, Benson DM, Mundy-Bosse BL, Freud AG, Caligiuri MA, Yu J. The IL-15-AKT-XBP1s signaling pathway contributes to effector functions and survival in human NK cells. Nat Immunol 2019; 20:10-17. [PMID: 30538328 PMCID: PMC6293989 DOI: 10.1038/s41590-018-0265-1] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2017] [Accepted: 10/18/2018] [Indexed: 01/21/2023]
Abstract
Interleukin 15 (IL-15) is one of the most important cytokines that regulate the biology of natural killer (NK) cells1. Here we identified a signaling pathway-involving the serine-threonine kinase AKT and the transcription factor XBP1s, which regulates unfolded protein response genes2,3-that was activated in response to IL-15 in human NK cells. IL-15 induced the phosphorylation of AKT, which led to the deubiquitination, increased stability and nuclear accumulation of XBP1s protein. XBP1s bound to and recruited the transcription factor T-BET to the gene encoding granzyme B, leading to increased transcription. XBP1s positively regulated the cytolytic activity of NK cells against leukemia cells and was also required for IL-15-mediated NK cell survival through an anti-apoptotic mechanism. Thus, the newly identified IL-15-AKT-XBP1s signaling pathway contributes to enhanced effector functions and survival of human NK cells.
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Affiliation(s)
- Yufeng Wang
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Yibo Zhang
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
| | - Ping Yi
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Third Affiliated Hospital, Third Military Medical University, Chongqing, China
| | - Wenjuan Dong
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, CA, USA
| | - Ansel P Nalin
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Medical Scientist Training Program, The Ohio State University, Columbus, OH, USA
| | - Jianying Zhang
- Division of Biostatistics, Department of Information Sciences, City of Hope National Medical Center, Duarte, CA, USA
| | - Zheng Zhu
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, CA, USA
| | - Lichao Chen
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
| | - Don M Benson
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Bethany L Mundy-Bosse
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, Ohio, USA
| | - Aharon G Freud
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA
- Department of Pathology, The Ohio State University, Columbus, OH, USA
| | - Michael A Caligiuri
- Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, CA, USA
- Hematologic Malignancies and Stem Cell Transplantation Institute, City of Hope National Medical Center, Duarte, CA, USA
| | - Jianhua Yu
- The Ohio State University Comprehensive Cancer Center, Columbus, OH, USA.
- Division of Hematology, Department of Internal Medicine, The Ohio State University, Columbus, Ohio, USA.
- Department of Hematology and Hematopoietic Cell Transplantation, City of Hope National Medical Center, Duarte, CA, USA.
- Hematologic Malignancies and Stem Cell Transplantation Institute, City of Hope National Medical Center, Duarte, CA, USA.
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21
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Up-regulation of FGFBP1 signaling contributes to miR-146a-induced angiogenesis in human umbilical vein endothelial cells. Sci Rep 2016; 6:25272. [PMID: 27121396 PMCID: PMC4848533 DOI: 10.1038/srep25272] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Accepted: 04/14/2016] [Indexed: 12/24/2022] Open
Abstract
Recent microRNA expression profiling studies have documented an up-regulation of miR-146a in several angiogenesis models. However, the underlying molecular mechanism of miR-146a in the angiogenic activity of endothelial cells has not been clearly elucidated. The present study was aimed to evaluate whether miR-146a promotes angiogenesis in HUVECs by increasing FGFBP1 expression via directly targeting CREB3L1. miR-146a was over expressed in HUVECs via lentiviral-miR-146a. Expression profiling analysis found miR-146a over expression resulted in up-regulation of angiogenesis and cytokine activity associated genes including FGF2. Further a combination of bioinformatics and experimental analyses demonstrated the CREB3L1 as a bona fide functional target of miR-146a during angiogenesis. Moreover, CREB3L1 inhibited luciferase expression from FGFBP1 promoter containing only CRE elements. Furthermore, CREB3L1 inhibited FGFBP1 expression by binding to two CRE-like sites located at approximately −1780–1777 and −868–865 bp relative to the FGFBP1 transcription start site. Additionally, ectopic expression of CREB3L1 decreased miR-146a-induced FGF2 secretion. These findings indicate that the miR-146a-CREB3L1-FGFBP1 signaling axis plays an important role in the regulation of angiogenesis in HUVECs and provides a potential therapeutic target for anti-angiogenic therapeutics.
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22
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Wang H, Sun RQ, Camera D, Zeng XY, Jo E, Chan SMH, Herbert TP, Molero JC, Ye JM. Endoplasmic reticulum stress up-regulates Nedd4-2 to induce autophagy. FASEB J 2016; 30:2549-56. [PMID: 27022162 DOI: 10.1096/fj.201500119] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Accepted: 03/21/2016] [Indexed: 01/08/2023]
Abstract
The accumulation of unfolded proteins within the endoplasmic reticulum (ER) causes ER stress and activation of unfolded protein response (UPR). This response can trigger ER-associated degradation and autophagy, which clear unfolded proteins and restore protein homeostasis. Recently, it has become clear that ubiquitination plays an important role in the regulation of autophagy. In the present study, we investigated how the E3 ubiquitin ligase neural precursor cell-expressed, developmentally down-regulated protein 4-2 (Nedd4-2) interacts with ER stress and autophagy. In mice, we found that an increase in the expression of Nedd4-2, which was concomitant with the activation of the UPR and autophagy, was caused by a prolonged high-fructose and high-fat diet that induces ER stress in the liver. Pharmacologic induction of ER stress also led to an increase in Nedd4-2 expression in cultured cells, which was coincident with UPR and autophagy activation. The inhibition of inositol-requiring enzyme 1 significantly suppressed Nedd4-2 expression. Moreover, increased Nedd4-2 expression in vivo was closely associated with the activation of inositol-requiring enzyme 1 and increased expression of the spliced form of X-box binding protein 1. Furthermore, knockdown of Nedd4-2 in cultured cells suppressed both basal autophagy and ER stress-induced autophagy, whereas overexpression of Nedd4-2-induced autophagy. Taken together, our findings provide evidence that Nedd4-2 is up-regulated in response to ER stress by the spliced form of X-box binding protein 1 and that this is important in the induction of an appropriate autophagic response.-Wang, H. Sun, R.-Q., Camera, D., Zeng, X.-Y., Jo, E., Chan, S. M. H., Herbert, T. P., Molero, J. C., Ye, J.-M. Endoplasmic reticulum stress up-regulates Nedd4-2 to induce autophagy.
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Affiliation(s)
- Hao Wang
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Ruo-Qiong Sun
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Daria Camera
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Xiao-Yi Zeng
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Eunjung Jo
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Stanley M H Chan
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Terence P Herbert
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Juan C Molero
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
| | - Ji-Ming Ye
- Lipid Biology and Metabolic Disease Laboratory, School of Health and Biomedical Sciences, Royal Melbourne Institute of Technology (RMIT) University, Melbourne, Victoria, Australia
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Martínez G, Vidal R, Mardones P, Serrano F, Ardiles A, Wirth C, Valdés P, Thielen P, Schneider B, Kerr B, Valdés J, Palacios A, Inestrosa N, Glimcher L, Hetz C. Regulation of Memory Formation by the Transcription Factor XBP1. Cell Rep 2016; 14:1382-1394. [DOI: 10.1016/j.celrep.2016.01.028] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 11/02/2015] [Accepted: 01/05/2016] [Indexed: 12/12/2022] Open
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Induction of Kaposi's Sarcoma-Associated Herpesvirus-Encoded Viral Interleukin-6 by X-Box Binding Protein 1. J Virol 2015; 90:368-78. [PMID: 26491160 DOI: 10.1128/jvi.01192-15] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Accepted: 10/08/2015] [Indexed: 12/28/2022] Open
Abstract
UNLABELLED Kaposi's sarcoma-associated herpesvirus (KSHV) is the causative agent for Kaposi sarcoma (KS), primary effusion lymphoma (PEL), and a subset of multicentric Castleman disease (MCD). The KSHV life cycle has two principal gene repertoires, latent and lytic. KSHV viral interleukin-6 (vIL-6), an analog of human IL-6, is usually lytic; production of vIL-6 by involved plasmablasts is a central feature of KSHV-MCD. vIL-6 also plays a role in PEL and KS. We show that a number of plasmablasts from lymph nodes of patients with KSHV-MCD express vIL-6 but not ORF45, a KSHV lytic gene. We further show that vIL-6 is directly induced by the spliced (active) X-box binding protein-1 (XBP-1s), a transcription factor activated by endoplasmic reticulum (ER) stress and differentiation of B cells in lymph nodes. The promoter region of vIL-6 contains several potential XBP-response elements (XREs), and two of these elements in particular mediate the effect of XBP-1s. Mutation of these elements abrogates the response to XBP-1s but not to the KSHV replication and transcription activator (RTA). Also, XBP-1s binds to the vIL-6 promoter in the region of these XREs. Exposure of PEL cells to a chemical inducer of XBP-1s can induce vIL-6. Patient-derived PEL tumor cells that produce vIL-6 frequently coexpress XBP-1, and immunofluorescence staining of involved KSHV-MCD lymph nodes reveals that most plasmablasts expressing vIL-6 also coexpress XBP-1. These results provide evidence that XBP-1s is a direct activator of KSHV vIL-6 and that this is an important step in the pathogenesis of KSHV-MCD and PEL. IMPORTANCE Kaposi sarcoma herpesvirus (KSHV)-associated multicentric Castleman disease (KSHV-MCD) is characterized by severe inflammatory symptoms caused by an excess of cytokines, particularly KSHV-encoded viral interleukin-6 (vIL-6) produced by lymph node plasmablasts. vIL-6 is usually a lytic gene. We show that a number of KSHV-MCD lymph node plasmablasts express vIL-6 but do not have full lytic KSHV replication. Differentiating lymph node B cells express spliced (active) X-box binding protein-1 (XBP-1s). We show that XBP-1s binds to the promoter of vIL-6 and can directly induce production of vIL-6 through X-box protein response elements on the vIL-6 promoter region. We further show that chemical inducers of XBP-1s can upregulate production of vIL-6. Finally, we show that most vIL-6-producing plasmablasts from lymph nodes of KSHV-MCD patients coexpress XBP-1s. These results demonstrate that XBP-1s can directly induce vIL-6 and provide evidence that this is a key step in the pathogenesis of KSHV-MCD and other KSHV-induced diseases.
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Kuwabara WMT, Zhang L, Schuiki I, Curi R, Volchuk A, Alba-Loureiro TC. NADPH oxidase-dependent production of reactive oxygen species induces endoplasmatic reticulum stress in neutrophil-like HL60 cells. PLoS One 2015; 10:e0116410. [PMID: 25668518 PMCID: PMC4323339 DOI: 10.1371/journal.pone.0116410] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Accepted: 12/09/2014] [Indexed: 01/20/2023] Open
Abstract
Reactive oxygen species (ROS) primarily produced via NADPH oxidase play an important role for killing microorganisms in neutrophils. In this study we examined if ROS production in Human promyelocytic leukemia cells (HL60) differentiated into neutrophil-like cells (dHL60) induces ER stress and activates the unfolded protein response (UPR). To cause ROS production cells were treated with PMA or by chronic hyperglycemia. Chronic hyperglycemia failed to induce ROS production and did not cause activation of the UPR in dHL60 cells. PMA, a pharmacologic NADPH oxidase activator, induced ER stress in dHL60 cells as monitored by IRE-1 and PERK pathway activation, and this was independent of calcium signaling. The NADPH oxidase inhibitor, DPI, abolished both ROS production and UPR activation. These results show that ROS produced by NADPH oxidase induces ER stress and suggests a close association between the redox state of the cell and the activation of the UPR in neutrophil-like HL60 cells.
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Affiliation(s)
| | - Liling Zhang
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Irmgard Schuiki
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
| | - Rui Curi
- Department of Physiology and Biophysics, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil
| | - Allen Volchuk
- Department of Physiology, University of Toronto, Toronto, Ontario, Canada
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Gaudette BT, Iwakoshi NN, Boise LH. Bcl-xL protein protects from C/EBP homologous protein (CHOP)-dependent apoptosis during plasma cell differentiation. J Biol Chem 2014; 289:23629-40. [PMID: 25023286 DOI: 10.1074/jbc.m114.569376] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Although it is known that the unfolded protein response (UPR) plays a significant role in the process of plasma cell differentiation, the contribution of the individual sensors of the UPR to this process remains unclear. In this study we examine the death signals and compensatory survival signals activated during B cell activation and the first stages of plasma cell differentiation. During in vitro differentiation of both primary murine B cells and the Bcl1 cell line, we demonstrate that in addition to activation of the physiological UPR, changes in the expression of several Bcl-2 proteins occur, which are consistent with a lowering of the apoptotic threshold of the cell. Specifically, we observed decreased expression of Bcl-2 and Mcl-1 and increased expression of the proapoptotic protein Bim. However, these changes were countered by Bcl-xL induction, which is necessary to protect differentiating cells both from ER stress-induced death by tunicamycin and from the death signals inherent in differentiation. Consistent with differentiating cells becoming dependent on Bcl-xL for survival, the addition of ABT-737 resulted in apoptosis in differentiating cells through the inhibition of sequestration of Bim. Confirming this result, differentiation in the context of RNAi-mediated Bcl-xL knockdown also induced apoptosis. This cell death is C/EBP homologous protein (CHOP)-dependent, connecting these events to the UPR. Thus plasma cell differentiation proceeds through a Bcl-xL-dependent intermediate.
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Affiliation(s)
- Brian T Gaudette
- From the Departments of Hematology and Medical Oncology, Cell Biology and Winship Cancer Institute, and
| | - Neal N Iwakoshi
- the Department of Surgery and Emory Transplant Center, Emory University, Atlanta, Georgia 30322
| | - Lawrence H Boise
- From the Departments of Hematology and Medical Oncology, Cell Biology and Winship Cancer Institute, and
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27
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Xu X, Park JG, So JS, Hur KY, Lee AH. Transcriptional regulation of apolipoprotein A-IV by the transcription factor CREBH. J Lipid Res 2014; 55:850-9. [PMID: 24598141 DOI: 10.1194/jlr.m045104] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
cAMP responsive element-binding protein H (CREBH) is an endoplasmic reticulum (ER) anchored transcription factor that is highly expressed in the liver and small intestine and implicated in nutrient metabolism and proinflammatory response. ApoA-IV is a glycoprotein secreted primarily by the intestine and to a lesser degree by the liver. ApoA-IV expression is suppressed in CREBH-deficient mice and strongly induced by enforced expression of the constitutively active form of CREBH, indicating that CREBH is the major transcription factor regulating Apoa4 gene expression. Here, we show that CREBH directly controls Apoa4 expression through two tandem CREBH binding sites (5'-CCACGTTG-3') located on the promoter, which are conserved between human and mouse. Chromatin immunoprecipitation and electrophoretic mobility-shift assays demonstrated specific association of CREBH with the CREBH binding sites. We also demonstrated that a substantial amount of CREBH protein was basally processed to the active nuclear form in normal mouse liver, which was further increased in steatosis induced by high-fat diet or fasting, increasing apoA-IV expression. However, we failed to find significant activation of CREBH in response to ER stress, arguing against the critical role of CREBH in ER stress response.
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Affiliation(s)
- Xu Xu
- Department of Pathology and Laboratory Medicine, Weill Cornell Medical College, New York, NY
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28
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Du Z, Treiber D, McCoy RE, Miller AK, Han M, He F, Domnitz S, Heath C, Reddy P. Non-invasive UPR monitoring system and its applications in CHO production cultures. Biotechnol Bioeng 2013; 110:2184-94. [DOI: 10.1002/bit.24877] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 02/15/2013] [Indexed: 02/04/2023]
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29
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Peng J, Chen YY, Yang LX, Zhao XY, Gao ZQ, Yang J, Wu WT, Wang HJ, Wang JC, Qian J, Chen HY, Jin L, Bai CX, Han BH, Lu DR. XBP1 promoter polymorphism modulates platinum-based chemotherapy gastrointestinal toxicity for advanced non-small cell lung cancer patients. Lung Cancer 2013; 80:333-8. [PMID: 23510626 DOI: 10.1016/j.lungcan.2013.02.012] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Revised: 12/12/2012] [Accepted: 02/17/2013] [Indexed: 01/24/2023]
Abstract
BACKGROUND The X-box binding protein 1 (XBP1) is a critical transcription factor in the endoplasmic reticulum stress response, which is essential for the maintenance of cellular homeostasis. Here, we investigated whether the regulatory variant rs2269577 of the XBP1 gene influences clinical outcome in advanced non-small cell lung cancer (NSCLC) patients undergoing platinum-based chemotherapy. PATIENTS AND METHODS We recruited 663 Chinese patients with advanced NSCLC treated with platinum-based regimens and assessed the association between rs2269577 and clinical outcome. Subsequent functional analyses, including real-time quantitative PCR and dual-luciferase assays, were performed to explore possible molecular mechanisms. RESULTS The G/G genotype of rs2269577 was significantly associated with severe gastrointestinal toxicity compared with the homozygous C/C genotype (P=0.012, odds ratio=2.755), particularly in the female, performance status 0-1, and adenocarcinoma subgroups. No significant relevance was found between rs2269577 and treatment efficacy. In gastric epithelial cells, in vitro molecular analyses demonstrated that XBP1 mRNA expression levels decreased after treatment with cisplatin and the G allele of rs2269577 weakened the transcriptional activity of the XBP1 promoter. CONCLUSION This is the first study to evaluate the effect of XBP1 polymorphism on severe chemotherapy-related adverse outcomes in platinum-treated advanced NSCLC patients using both pharmacogenomics and functional molecular analyses.
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Affiliation(s)
- J Peng
- State Key Laboratory of Genetic Engineering and MOE Key Laboratory of Contemporary Anthropology, Institute of Genetics, School of Life Sciences, Fudan University, Shanghai, China
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30
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Margariti A, Li H, Chen T, Martin D, Vizcay-Barrena G, Alam S, Karamariti E, Xiao Q, Zampetaki A, Zhang Z, Wang W, Jiang Z, Gao C, Ma B, Chen YG, Cockerill G, Hu Y, Xu Q, Zeng L. XBP1 mRNA splicing triggers an autophagic response in endothelial cells through BECLIN-1 transcriptional activation. J Biol Chem 2013; 288:859-72. [PMID: 23184933 PMCID: PMC3543035 DOI: 10.1074/jbc.m112.412783] [Citation(s) in RCA: 209] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2012] [Revised: 11/13/2012] [Indexed: 11/06/2022] Open
Abstract
Sustained activation of X-box-binding protein 1 (XBP1) results in endothelial cell (EC) apoptosis and atherosclerosis development. The present study provides evidence that XBP1 mRNA splicing triggered an autophagic response in ECs by inducing autophagic vesicle formation and markers of autophagy BECLIN-1 and microtubule-associated protein 1 light chain 3β (LC3-βII). Endostatin activated autophagic gene expression through XBP1 mRNA splicing in an inositol-requiring enzyme 1α (IRE1α)-dependent manner. Knockdown of XBP1 or IRE1α by shRNA in ECs ablated endostatin-induced autophagosome formation. Importantly, data from arterial vessels from XBP1 EC conditional knock-out (XBP1eko) mice demonstrated that XBP1 deficiency in ECs reduced the basal level of LC3β expression and ablated response to endostatin. Chromatin immunoprecipitation assays further revealed that the spliced XBP1 isoform bound directly to the BECLIN-1 promoter at the region from nt -537 to -755. BECLIN-1 deficiency in ECs abolished the XBP1-induced autophagy response, whereas spliced XBP1 did not induce transcriptional activation of a truncated BECLIN-1 promoter. These results suggest that XBP1 mRNA splicing triggers an autophagic signal pathway through transcriptional regulation of BECLIN-1.
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Affiliation(s)
- Andriana Margariti
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Hongling Li
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Ting Chen
- the Department of Cardiology, First Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310003, China
| | - Daniel Martin
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Gema Vizcay-Barrena
- the Centre for Ultrastructural Imaging, King's College London, Guy's Campus, London WC2R 2LS, United Kingdom
| | - Saydul Alam
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Eirini Karamariti
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Qingzhong Xiao
- the Centre for Clinical Pharmacology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London EC1M 6BQ, United Kingdom
| | - Anna Zampetaki
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Zhongyi Zhang
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Wen Wang
- the School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, United Kingdom
| | - Zhixin Jiang
- the Centre Laboratory, 305th Hospital of the People's Liberation Army, Beijing 100017, China
| | - Chan Gao
- the State Key Laboratory of Bio-membrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China, and
| | - Benyu Ma
- the State Key Laboratory of Bio-membrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China, and
| | - Ye-Guang Chen
- the State Key Laboratory of Bio-membrane and Membrane Biotechnology, School of Life Sciences, Tsinghua University, Beijing 100084, China, and
| | - Gillian Cockerill
- the Department of Cardiovascular Science, St. George's University of London, London SW17 0RE, United Kingdom
| | - Yanhua Hu
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Qingbo Xu
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
| | - Lingfang Zeng
- From the Cardiovascular Division, King's College London BHF Centre, 125 Coldharbour Lane, London SE5 9NU, United Kingdom
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Abstract
Estrogen receptor (ER) is a hormone-regulated transcription factor that controls cell division and differentiation in the ovary, breast, and uterus. The expression of ER is a common feature of the majority of breast cancers, which is used as a therapeutic target. Recent genetic studies have shown that ER binding occurs in regions distant to the promoters of estrogen target genes. These studies have also demonstrated that ER binding is accompanied with the binding of other transcription factors, which regulate the function of ER and response to anti-estrogen therapies. In this review, we explain how these factors influence the interaction of ER to chromatin and their cooperation for ER transcriptional activity. Moreover, we describe how the expression of these factors dictates the response to anti-estrogen therapies. Finally, we discuss how cytoplasmatic signaling pathways may modulate the function of ER and its cooperating transcription factors.
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32
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Unfolded protein response, activated by OASIS family transcription factors, promotes astrocyte differentiation. Nat Commun 2012; 3:967. [PMID: 22828627 DOI: 10.1038/ncomms1971] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2012] [Accepted: 06/22/2012] [Indexed: 01/27/2023] Open
Abstract
OASIS is a member of the CREB/ATF family of transcription factors and modulates cell- or tissue-specific unfolded protein response signalling. Here we show that this modulation has a critical role in the differentiation of neural precursor cells into astrocytes. Cerebral cortices of mice specifically deficient in OASIS (Oasis(-/-)) contain fewer astrocytes and more neural precursor cells than those of wild-type mice during embryonic development. Furthermore, astrocyte differentiation is delayed in primary cultured Oasis(-/-) neural precursor cells. The transcription factor Gcm1, which is necessary for astrocyte differentiation in Drosophila, is revealed to be a target of OASIS. Introduction of Gcm1 into Oasis(-/-) neural precursor cells improves the delayed differentiation of neural precursor cells into astrocytes by accelerating demethylation of the Gfap promoter. Gcm1 expression is temporally controlled by the unfolded protein response through interactions between OASIS family members during astrocyte differentiation. Taken together, our findings demonstrate a novel mechanism by which OASIS and its associated family members are modulated by the unfolded protein response to finely control astrocyte differentiation.
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Clarke R, Cook KL, Hu R, Facey COB, Tavassoly I, Schwartz JL, Baumann WT, Tyson JJ, Xuan J, Wang Y, Wärri A, Shajahan AN. Endoplasmic reticulum stress, the unfolded protein response, autophagy, and the integrated regulation of breast cancer cell fate. Cancer Res 2012; 72:1321-31. [PMID: 22422988 PMCID: PMC3313080 DOI: 10.1158/0008-5472.can-11-3213] [Citation(s) in RCA: 157] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
How breast cancer cells respond to the stress of endocrine therapies determines whether they will acquire a resistant phenotype or execute a cell-death pathway. After a survival signal is successfully executed, a cell must decide whether it should replicate. How these cell-fate decisions are regulated is unclear, but evidence suggests that the signals that determine these outcomes are highly integrated. Central to the final cell-fate decision is signaling from the unfolded protein response, which can be activated following the sensing of stress within the endoplasmic reticulum. The duration of the response to stress is partly mediated by the duration of inositol-requiring enzyme-1 activation following its release from heat shock protein A5. The resulting signals appear to use several B-cell lymphoma-2 family members to both suppress apoptosis and activate autophagy. Changes in metabolism induced by cellular stress are key components of this regulatory system, and further adaptation of the metabolome is affected in response to stress. Here we describe the unfolded protein response, autophagy, and apoptosis, and how the regulation of these processes is integrated. Central topologic features of the signaling network that integrate cell-fate regulation and decision execution are discussed.
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Affiliation(s)
- Robert Clarke
- Department of Oncology, Georgetown University School of Medicine, Washington, DC 20057, USA.
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Haeri M, Knox BE. Endoplasmic Reticulum Stress and Unfolded Protein Response Pathways: Potential for Treating Age-related Retinal Degeneration. J Ophthalmic Vis Res 2012; 7:45-59. [PMID: 22737387 PMCID: PMC3381108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2011] [Accepted: 12/18/2011] [Indexed: 11/24/2022] Open
Abstract
Accumulation of misfolded proteins in the endoplasmic reticulum (ER) and their aggregation impair normal cellular function and can be toxic, leading to cell death. Prolonged expression of misfolded proteins triggers ER stress, which initiates a cascade of reactions called the unfolded protein response (UPR). Protein misfolding is the basis for a variety of disorders known as ER storage or conformational diseases. There are an increasing number of eye disorders associated with misfolded proteins and pathologic ER responses, including retinitis pigmentosa (RP). Herein we review the basic cellular and molecular biology of UPR with focus on pathways that could be potential targets for treating retinal degenerative diseases.
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Affiliation(s)
- Mohammad Haeri
- Correspondence to: Mohammad Haeri, MD, PhD. Departments of Neuroscience and Physiology and Ophthalmology, SUNY Upstate Medical University, WH3220, Syracuse, NY 13210, USA; Tel: +1 315 464 8148, Fax: +1 315 464 7725; e-mail:
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35
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p38 MAPK-mediated regulation of Xbp1s is crucial for glucose homeostasis. Nat Med 2011; 17:1251-60. [PMID: 21892182 DOI: 10.1038/nm.2449] [Citation(s) in RCA: 170] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/20/2011] [Indexed: 12/17/2022]
Abstract
Here we show that p38 mitogen-activated protein kinase (p38 MAPK) phosphorylates the spliced form of X-box binding protein 1 (Xbp1s) on its Thr48 and Ser61 residues and greatly enhances its nuclear migration in mice, whereas mutation of either residue to alanine substantially reduces its nuclear translocation and activity. We also show that p38 MAPK activity is markedly reduced in the livers of obese mice compared with lean mice. Further, we show that activation of p38 MAPK by expression of constitutively active MAP kinase kinase 6 (MKK6Glu) greatly enhances nuclear translocation of Xbp1s, reduces endoplasmic reticulum stress and establishes euglycemia in severely obese and diabetic mice. Hence, our results define a crucial role for phosphorylation on Thr48 and Ser61 of Xbp1s in the maintenance of glucose homeostasis in obesity, and they suggest that p38 MAPK activation in the livers of obese mice could lead to a new therapeutic approach to the treatment of type 2 diabetes.
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Liu Y, Zhang X, Liang Y, Yu H, Chen X, Zheng T, Zheng B, Wang L, Zhao L, Shi C, Zhao S. Targeting X box-binding protein-1 (XBP1) enhances sensitivity of glioma cells to oxidative stress. Neuropathol Appl Neurobiol 2011; 37:395-405. [DOI: 10.1111/j.1365-2990.2010.01155.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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37
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Wang FM, Ouyang HJ. Regulation of unfolded protein response modulator XBP1s by acetylation and deacetylation. Biochem J 2011; 433:245-52. [PMID: 20955178 PMCID: PMC3477812 DOI: 10.1042/bj20101293] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
XBP1 (X-box-binding protein 1) is a key modulator of the UPR (unfolded protein response), which is involved in a wide range of pathological and physiological processes. The mRNA encoding the active spliced form of XBP1 (XBP1s) is generated from the unspliced form by IRE1 (inositol-requiring enzyme 1) during the UPR. However, the post-translational modulation of XBP1s remains largely unknown. In the present study, we demonstrate that XBP1s is a target of acetylation and deacetylation mediated by p300 and SIRT1 (sirtuin 1) respectively. p300 increases the acetylation and protein stability of XBP1s, and enhances its transcriptional activity, whereas SIRT1 deacetylates XBP1s and inhibits its transcriptional activity. Deficiency of SIRT1 enhances XBP1s-mediated luciferase reporter activity in HEK (human embryonic kidney)-293 cells and the up-regulation of XBP1s target gene expression under ER (endoplasmic reticulum) stress in MEFs (mouse embryonic fibroblasts). Consistent with XBP1s favouring cell survival under ER stress, Sirt1-/- MEFs display a greater resistance to ER-stress-induced apoptotic cell death compared with Sirt1+/+ MEFs. Taken together, these results suggest that acetylation/deacetylation constitutes an important post-translational mechanism in controlling protein levels, as well as the transcriptional activity, of XBP1s. The present study provides a novel insight into the molecular mechanisms by which SIRT1 regulates UPR signalling.
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Affiliation(s)
- Feng-Ming Wang
- Division of Hematology & Oncology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15240, USA
- The State Key Laboratory of Oral Diseases, Sichuan University, Chengdu 610041, PR China
| | - Hong-Jiao Ouyang
- Division of Hematology & Oncology, Department of Medicine, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15240, USA
- Department of Microbiology and Molecular Genetics, School of Medicine, University of Pittsburgh, Pittsburgh, PA 15240, USA
- Department of Comprehensive Care, Restorative Dentistry, and Endodontics, School of Dental Medicine, University of Pittsburgh, PA 15240, USA
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Clarke R, Shajahan AN, Wang Y, Tyson JJ, Riggins RB, Weiner LM, Bauman WT, Xuan J, Zhang B, Facey C, Aiyer H, Cook K, Hickman FE, Tavassoly I, Verdugo A, Chen C, Zwart A, Wärri A, Hilakivi-Clarke LA. Endoplasmic reticulum stress, the unfolded protein response, and gene network modeling in antiestrogen resistant breast cancer. Horm Mol Biol Clin Investig 2011; 5:35-44. [PMID: 23930139 DOI: 10.1515/hmbci.2010.073] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Lack of understanding of endocrine resistance remains one of the major challenges for breast cancer researchers, clinicians, and patients. Current reductionist approaches to understanding the molecular signaling driving resistance have offered mostly incremental progress over the past 10 years. As the field of systems biology has begun to mature, the approaches and network modeling tools being developed and applied therein offer a different way to think about how molecular signaling and the regulation of critical cellular functions are integrated. To gain novel insights, we first describe some of the key challenges facing network modeling of endocrine resistance, many of which arise from the properties of the data spaces being studied. We then use activation of the unfolded protein response (UPR) following induction of endoplasmic reticulum stress in breast cancer cells by antiestrogens, to illustrate our approaches to computational modeling. Activation of UPR is a key determinant of cell fate decision making and regulation of autophagy and apoptosis. These initial studies provide insight into a small subnetwork topology obtained using differential dependency network analysis and focused on the UPR gene XBP1. The XBP1 subnetwork topology incorporates BCAR3, BCL2, BIK, NFκB, and other genes as nodes; the connecting edges represent the dependency structures amongst these nodes. As data from ongoing cellular and molecular studies become available, we will build detailed mathematical models of this XBP1-UPR network.
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Affiliation(s)
- Robert Clarke
- Department of Oncology, Georgetown University School of Medicine, Washington, DC 20057, U.S.A. ; Lombardi Comprehensive Cancer Center, Georgetown University School of Medicine, Washington, DC 20057, U.S.A
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Takata A, Kakiuchi C, Ishiwata M, Kanba S, Kato T. Behavioral and gene expression analyses in heterozygous XBP1 knockout mice: Possible contribution of chromosome 11qA1 locus to prepulse inhibition. Neurosci Res 2010; 68:250-5. [DOI: 10.1016/j.neures.2010.07.2042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2010] [Revised: 07/26/2010] [Accepted: 07/28/2010] [Indexed: 11/27/2022]
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Abstract
The UPR (unfolded protein response), a cellular defence mechanism against misfolded protein accumulation in the ER (endoplasmic reticulum), is associated with many human diseases such as aging, cancer and diabetes. XBP1 (X-box-binding protein 1), a key transcription factor of the UPR, is critical in maintaining ER homoeostasis. Nevertheless, the mechanism by which XBP1 transcriptional activity is regulated remains unexplored. In the present study we show that XBP1s, the active spliced form of XBP1 protein, is SUMOylated, mainly by PIAS2 [protein inhibitor of activated STAT (signal transducer and activator of transcription) 2] at two lysine residues located in the C-terminal transactivation domain. Ablation of these SUMOylation events significantly enhances the transcriptional activity of XBP1s towards UPR target genes. Thus our results reveal an unexpected role for SUMO (small ubiquitin-related modifier) in the regulation of UPR activation and ER homeostasis.
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Jolma A, Kivioja T, Toivonen J, Cheng L, Wei G, Enge M, Taipale M, Vaquerizas JM, Yan J, Sillanpää MJ, Bonke M, Palin K, Talukder S, Hughes TR, Luscombe NM, Ukkonen E, Taipale J. Multiplexed massively parallel SELEX for characterization of human transcription factor binding specificities. Genome Res 2010; 20:861-73. [PMID: 20378718 PMCID: PMC2877582 DOI: 10.1101/gr.100552.109] [Citation(s) in RCA: 312] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2009] [Accepted: 03/22/2010] [Indexed: 01/15/2023]
Abstract
The genetic code-the binding specificity of all transfer-RNAs--defines how protein primary structure is determined by DNA sequence. DNA also dictates when and where proteins are expressed, and this information is encoded in a pattern of specific sequence motifs that are recognized by transcription factors. However, the DNA-binding specificity is only known for a small fraction of the approximately 1400 human transcription factors (TFs). We describe here a high-throughput method for analyzing transcription factor binding specificity that is based on systematic evolution of ligands by exponential enrichment (SELEX) and massively parallel sequencing. The method is optimized for analysis of large numbers of TFs in parallel through the use of affinity-tagged proteins, barcoded selection oligonucleotides, and multiplexed sequencing. Data are analyzed by a new bioinformatic platform that uses the hundreds of thousands of sequencing reads obtained to control the quality of the experiments and to generate binding motifs for the TFs. The described technology allows higher throughput and identification of much longer binding profiles than current microarray-based methods. In addition, as our method is based on proteins expressed in mammalian cells, it can also be used to characterize DNA-binding preferences of full-length proteins or proteins requiring post-translational modifications. We validate the method by determining binding specificities of 14 different classes of TFs and by confirming the specificities for NFATC1 and RFX3 using ChIP-seq. Our results reveal unexpected dimeric modes of binding for several factors that were thought to preferentially bind DNA as monomers.
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Affiliation(s)
- Arttu Jolma
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
| | - Teemu Kivioja
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
- Department of Computer Science, FI-00014 University of Helsinki, Helsinki, Finland
| | - Jarkko Toivonen
- Department of Computer Science, FI-00014 University of Helsinki, Helsinki, Finland
| | - Lu Cheng
- Department of Computer Science, FI-00014 University of Helsinki, Helsinki, Finland
| | - Gonghong Wei
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
| | - Martin Enge
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
| | - Mikko Taipale
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
| | - Juan M. Vaquerizas
- EMBL–European Bioinformatics Institute, Cambridge CB10 1SD, United Kingdom
| | - Jian Yan
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
| | - Mikko J. Sillanpää
- Department of Mathematics and Statistics, FI-00014 University of Helsinki, Helsinki, Finland
| | - Martin Bonke
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
| | - Kimmo Palin
- Department of Computer Science, FI-00014 University of Helsinki, Helsinki, Finland
| | - Shaheynoor Talukder
- Department of Molecular Genetics and Banting and Best Department of Medical Research, University of Toronto, Toronto, ON M4T 2J4, Canada
| | - Timothy R. Hughes
- Department of Molecular Genetics and Banting and Best Department of Medical Research, University of Toronto, Toronto, ON M4T 2J4, Canada
| | | | - Esko Ukkonen
- Department of Computer Science, FI-00014 University of Helsinki, Helsinki, Finland
| | - Jussi Taipale
- Department of Molecular Medicine, National Public Health Institute (KTL) and Genome-Scale Biology Program, Institute of Biomedicine and High Throughput Center, University of Helsinki, Biomedicum, Helsinki, Finland
- Department of Biosciences and Nutrition, Karolinska Institutet, Stockholm, Sweden
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A common polymorphism in the cannabinoid receptor 1 (CNR1) gene is associated with antipsychotic-induced weight gain in Schizophrenia. Neuropsychopharmacology 2010; 35:1315-24. [PMID: 20107430 PMCID: PMC3055343 DOI: 10.1038/npp.2009.235] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Antipsychotic-induced weight gain has emerged as a serious complication in the treatment of patients with atypical antipsychotic drugs. The cannabinoid receptor 1 (CNR1) is expressed centrally in the hypothalamic region and associated with appetite and satiety, as well as peripherally. An antagonist of CNR1 (rimonabant) has been effective in causing weight loss in obese patients indicating that CNR1 might be important in antipsychotic-induced weight gain. Twenty tag SNPs were analyzed in 183 patients who underwent treatment (with either clozapine, olanzapine, haloperidol, or risperidone) for chronic schizophrenia were evaluated for antipsychotic-induced weight gain for up to 14 weeks. The polymorphism rs806378 was nominally associated with weight gain in patients of European ancestry treated with clozapine or olanzapine. 'T' allele carriers (CT+TT) gained more weight (5.96%), than the CC carriers (2.76%, p=0.008, FDR q-value=0.12). This translated into approximately 2.2 kg more weight gain in patients carrying the T allele than the patients homozygous for the CC genotype (CC vs CT+TT, 2.21+/-4.51 vs 4.33+/-3.89 kg; p=0.022). This was reflected in the allelic analysis (C vs T allele, 3.84 vs 5.83%, p=0.035). We conducted electrophoretic mobility shift assays which showed that the presence of the T allele created a binding site for arylhydrocarbon receptor translocator (ARNT), a member of the basic helix-loop-helix/Per-Arnt-Sim protein family. In this study, we provide evidence that the CNR1 gene may be associated with antipsychotic-induced weight gain in chronic schizophrenia patients. However, these observations were made in a relatively small patient population; therefore these results need to be replicated in larger sample sets.
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Ghosh R, Lipson KL, Sargent KE, Mercurio AM, Hunt JS, Ron D, Urano F. Transcriptional regulation of VEGF-A by the unfolded protein response pathway. PLoS One 2010; 5:e9575. [PMID: 20221394 PMCID: PMC2833197 DOI: 10.1371/journal.pone.0009575] [Citation(s) in RCA: 189] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2009] [Accepted: 02/15/2010] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Angiogenesis is crucial to many physiological and pathological processes including development and cancer cell survival. Vascular endothelial growth factor-A (VEGFA) is the predominant mediator of angiogenesis in the VEGF family. During development, adverse environmental conditions like nutrient deprivation, hypoxia and increased protein secretion occur. IRE1alpha, PERK, and ATF6alpha, master regulators of the unfolded protein response (UPR), are activated under these conditions and are proposed to have a role in mediating angiogenesis. PRINCIPAL FINDINGS Here we show that IRE1alpha, PERK, and ATF6alpha powerfully regulate VEGFA mRNA expression under various stress conditions. In Ire1alpha(-/-) and Perk(-/-) mouse embryonic fibroblasts and ATF6alpha-knockdown HepG2 cells, induction of VEGFA mRNA by endoplasmic reticulum stress is attenuated as compared to control cells. Embryonic lethality of Ire1alpha-/- mice is due to the lack of VEGFA induction in labyrinthine trophoblast cells of the developing placenta. Rescue of IRE1alpha and PERK in Ire1alpha(-/-) and Perk(-/-) cells respectively, prevents VEGFA mRNA attenuation. We further report that the induction of VEGFA by IRE1alpha, PERK and ATF6 involves activation of transcription factors, spliced-XBP-1, ATF4 and cleaved ATF6 respectively. CONCLUSIONS/SIGNIFICANCE Our results reveal that the IRE1alpha-XBP-1, PERK-ATF4, and ATF6alpha pathways constitute novel upstream regulatory pathways of angiogenesis by modulating VEGF transcription. Activation of these pathways helps the rapidly growing cells to obtain sufficient nutrients and growth factors for their survival under the prevailing hostile environmental conditions. These results establish an important role of the UPR in angiogenesis.
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Affiliation(s)
- Rajarshi Ghosh
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Kathryn L. Lipson
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Department of Physical and Biological Sciences, Western New England College, Springfield, Massachusetts, United States of America
| | - Karen E. Sargent
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Arthur M. Mercurio
- Department of Cancer Biology, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
| | - Joan S. Hunt
- Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, Kansas, United States of America
| | - David Ron
- Skirball Institute, New York University School of Medicine, New York, New York, United States of America
- Institute of Metabolic Sciences, University of Cambridge, Cambridge, United Kingdom
| | - Fumihiko Urano
- Program in Gene Function and Expression, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
- Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America
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44
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Abstract
X-box binding protein 1 (XBP1) is a unique basic region leucine zipper (bZIP) transcription factor whose active form is generated by a nonconventional splicing reaction upon disruption of homeostasis in the endoplasmic reticulum (ER) and activation of the unfolded protein response (UPR). XBP1, first identified as a key regulator of major histocompatibility complex (MHC) class II gene expression in B cells, represents the most conserved signaling component of UPR and is critical for cell fate determination in response to ER stress. Here we review recent advances in our understanding of this multifaceted transcription factor in health and diseases.
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Affiliation(s)
- Yin He
- *Graduate Program in Genetics and Development, Cornell University, Ithaca, NY, USA
| | - Shengyi Sun
- †Graduate Program in Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, USA
| | - Haibo Sha
- ‡Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Ziying Liu
- †Graduate Program in Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, USA
| | - Liu Yang
- †Graduate Program in Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, USA
| | - Zhen Xue
- §Graduate Program in Nutrition, Cornell University, Ithaca, NY, USA
| | - Hui Chen
- ‡Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
| | - Ling Qi
- *Graduate Program in Genetics and Development, Cornell University, Ithaca, NY, USA
- †Graduate Program in Biochemistry, Molecular and Cell Biology, Cornell University, Ithaca, NY, USA
- ‡Division of Nutritional Sciences, Cornell University, Ithaca, NY, USA
- §Graduate Program in Nutrition, Cornell University, Ithaca, NY, USA
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45
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Simmons SO, Fan CY, Ramabhadran R. Cellular stress response pathway system as a sentinel ensemble in toxicological screening. Toxicol Sci 2009; 111:202-25. [PMID: 19567883 DOI: 10.1093/toxsci/kfp140] [Citation(s) in RCA: 200] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
High costs, long test times, and societal concerns related to animal use have required the development of in vitro assays for the rapid and cost-effective toxicological evaluation and characterization of compounds in both the pharmaceutical and environmental arenas. Although the pharmaceutical industry has developed very effective, high-throughput in vitro assays for determining the therapeutic potential of compounds, the application of this approach to toxicological screening has been limited. A primary reason for this is that while drug candidate screens are directed to a specific target/mechanism, xenobiotics can cause toxicity through any of a myriad of undefined interactions with cellular components and processes. Given that it is not practical to design assays that can interrogate each potential toxicological target, an integrative approach is required if there is to be a rapid and low-cost toxicological evaluation of chemicals. Cellular stress response pathways offer a viable solution to the creation of a set of integrative assays as there is a limited and hence manageable set (a small ensemble of 10 or less) of major cellular stress response pathways through which cells mount a homoeostatic response to toxicants and which also participate in cell fate/death decisions. Further, over the past decades, these pathways have been well characterized at a molecular level thereby enabling the development of high-throughput cell-based assays using the components of the pathways. Utilization of the set of cellular stress response pathway-based assays as indicators of toxic interactions of chemicals with basic cellular machinery will potentially permit the clustering of chemicals based on biological response profiles of common mode of action (MOA) and also the inference of the specific MOA of a toxicant. This article reviews the biochemical characteristics of the stress response pathways, their common architecture that enables rapid activation during stress, their participation in cell fate decisions, the essential nature of these pathways to the organism, and the biochemical basis of their cross-talk that permits an assay ensemble screening approach. Subsequent sections describe how the stress pathway ensemble assay approach could be applied to screening potentially toxic compounds and discuss how this approach may be used to derive toxicant MOA from the biological activity profiles that the ensemble strategy provides. The article concludes with a review of the application of the stress assay concept to noninvasive in vivo assessments of chemical toxicants.
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Affiliation(s)
- Steven O Simmons
- Integrated Systems Toxicology Division, National Health and Environmental Effects Research Laboratory, U.S. EPA, Research Triangle Park, North Carolina 27711, USA
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Sha H, He Y, Chen H, Wang C, Zenno A, Shi H, Yang X, Zhang X, Qi L. The IRE1alpha-XBP1 pathway of the unfolded protein response is required for adipogenesis. Cell Metab 2009; 9:556-64. [PMID: 19490910 PMCID: PMC2963107 DOI: 10.1016/j.cmet.2009.04.009] [Citation(s) in RCA: 216] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 04/02/2009] [Accepted: 04/28/2009] [Indexed: 11/29/2022]
Abstract
Signaling cascades during adipogenesis culminate in the expression of two essential adipogenic factors, PPARgamma and C/EBPalpha. Here we demonstrate that the IRE1alpha-XBP1 pathway, the most conserved branch of the unfolded protein response (UPR), is indispensable for adipogenesis. Indeed, XBP1-deficient mouse embryonic fibroblasts and 3T3-L1 cells with XBP1 or IRE1alpha knockdown exhibit profound defects in adipogenesis. Intriguingly, C/EBPbeta, a key early adipogenic factor, induces Xbp1 expression by directly binding to its proximal promoter region. Subsequently, XBP1 binds to the promoter of Cebpa and activates its gene expression. The posttranscriptional splicing of Xbp1 mRNA by IRE1alpha is required as only the spliced form of XBP1 (XBP1s) rescues the adipogenic defect exhibited by XBP1-deficient cells. Taken together, our data show that the IRE1alpha-XBP1 pathway plays a key role in adipocyte differentiation by acting as a critical regulator of the morphological and functional transformations during adipogenesis.
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Affiliation(s)
- Haibo Sha
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
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47
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Lee AH, Glimcher LH. Intersection of the unfolded protein response and hepatic lipid metabolism. Cell Mol Life Sci 2009; 66:2835-50. [PMID: 19468685 DOI: 10.1007/s00018-009-0049-8] [Citation(s) in RCA: 80] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2009] [Revised: 05/05/2009] [Accepted: 05/06/2009] [Indexed: 12/20/2022]
Abstract
The liver plays a central role in whole-body lipid metabolism by governing the synthesis, oxidization, transport and excretion of lipids. The unfolded protein response (UPR) was identified as a signal transduction system that is activated by ER stress. Recent studies revealed a critical role of the UPR in hepatic lipid metabolism. The IRE1/XBP1 branch of the UPR is activated by high dietary carbohydrates and controls the expression of genes involved in fatty acid and cholesterol biosynthesis. PERK mediated eIF2alpha phosphorylation is also required for the expression of lipogenic genes and the development of hepatic steatosis, likely by activating C/EBP and PPARgamma transcription factors. Further studies to define the molecular pathways that lead to the activation of the UPR by nutritional cues in the liver, and their contribution to human metabolic disorders such as hepatic steatosis, atherosclerosis and type 2 diabetes that are associated with dysregulation of lipid homeostasis, are warranted.
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Affiliation(s)
- Ann-Hwee Lee
- Department of Immunology and Infectious Diseases, Harvard School of Public Health, Boston, MA 02115-6017, USA.
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48
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Hsiao JR, Chang KC, Chen CW, Wu SY, Su IJ, Hsu MC, Jin YT, Tsai ST, Takada K, Chang Y. Endoplasmic reticulum stress triggers XBP-1-mediated up-regulation of an EBV oncoprotein in nasopharyngeal carcinoma. Cancer Res 2009; 69:4461-7. [PMID: 19435892 DOI: 10.1158/0008-5472.can-09-0277] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Endoplasmic reticulum (ER) stress-activated unfolded protein response (UPR) plays multiple roles in cancer development, but its specific roles for virus-associated cancers have not been fully understood. It is still unknown whether ER stress/UPR occurs in and contributes to nasopharyngeal carcinoma (NPC), an epithelial malignancy closely associated with EBV. Here, we report that UPR proteins are frequently detected in NPC biopsies. In addition, we reveal that, in EBV-infected NPC cells, ER stress inducers up-regulate a potent EBV oncoprotein latent membrane protein 1 (LMP1), and the ER stress-induced LMP1 enhances production of interleukin-8. ER stress triggers LMP1 expression at a transcriptional level, activating a distal LMP1 promoter TR-L1. TR-L1 contains an ER stress-responsive element, which is targeted by an UPR protein XBP-1. Ectopic expression of XBP-1 induces LMP1 expression, and knockdown of XBP-1 blocks ER stress-triggered up-regulation of LMP1 in NPC cells. Furthermore, XBP-1 significantly correlates with LMP1 expression in NPC tumor biopsies. Therefore, this study not only provides a novel clue linking ER stress/UPR to EBV-associated NPC but also suggests that ER stress/UPR can promote virus-associated cancer in a unique way by driving expression of a viral oncogene.
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Affiliation(s)
- Jenn-Ren Hsiao
- Department of Otolaryngology, College of Medicine, National Cheng Kung University, Tainan, Taiwan
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49
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Clarke R, Shajahan AN, Riggins RB, Cho Y, Crawford A, Xuan J, Wang Y, Zwart A, Nehra R, Liu MC. Gene network signaling in hormone responsiveness modifies apoptosis and autophagy in breast cancer cells. J Steroid Biochem Mol Biol 2009; 114:8-20. [PMID: 19444933 PMCID: PMC2768542 DOI: 10.1016/j.jsbmb.2008.12.023] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Resistance to endocrine therapies, whether de novo or acquired, remains a major limitation in the ability to cure many tumors that express detectable levels of the estrogen receptor alpha protein (ER). While several resistance phenotypes have been described, endocrine unresponsiveness in the context of therapy-induced tumor growth appears to be the most prevalent. The signaling that regulates endocrine resistant phenotypes is poorly understood but it involves a complex signaling network with a topology that includes redundant and degenerative features. To be relevant to clinical outcomes, the most pertinent features of this network are those that ultimately affect the endocrine-regulated components of the cell fate and cell proliferation machineries. We show that autophagy, as supported by the endocrine regulation of monodansylcadaverine staining, increased LC3 cleavage, and reduced expression of p62/SQSTM1, plays an important role in breast cancer cells responding to endocrine therapy. We further show that the cell fate machinery includes both apoptotic and autophagic functions that are potentially regulated through integrated signaling that flows through key members of the BCL2 gene family and beclin-1 (BECN1). This signaling links cellular functions in mitochondria and endoplasmic reticulum, the latter as a consequence of induction of the unfolded protein response. We have taken a seed-gene approach to begin extracting critical nodes and edges that represent central signaling events in the endocrine regulation of apoptosis and autophagy. Three seed nodes were identified from global gene or protein expression analyses and supported by subsequent functional studies that established their abilities to affect cell fate. The seed nodes of nuclear factor kappa B (NFkappaB), interferon regulatory factor-1 (IRF1), and X-box binding protein-1 (XBP1)are linked by directional edges that support signal flow through a preliminary network that is grown to include key regulators of their individual function: NEMO/IKKgamma, nucleophosmin and ER respectively. Signaling proceeds through BCL2 gene family members and BECN1 ultimately to regulate cell fate.
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Affiliation(s)
- Robert Clarke
- Department of Oncology and Lombardi Comprehensive Cancer Center, Georgetown University School of Medicine, Washington, DC 20057, USA.
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50
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Abstract
Antioxidant molecules reduce oxidative stress and protect cells from reactive oxygen species (ROS)-mediated cellular damage and probably the development of cancer. We have investigated the contribution of X-box-binding protein (XBP1), a major endoplasmic reticulum stress-linked transcriptional factor, to cellular resistance to oxidative stress. After exposure to hydrogen peroxide (H(2)O(2)) or a strong ROS inducer parthenolide, loss of mitochondrial membrane potential (MMP) and subsequent cell death occurred more extensively in XBP1-deficient cells than wild-type mouse embryonic fibroblast cells, whereas two other anticancer agents induced death similarly in both cells. In XBP1-deficient cells, H(2)O(2) exposure induced more extensive ROS generation and prolonged p38 phosphorylation, and expression of several antioxidant molecules including catalase was lower. Knockdown of XBP1 decreased catalase expression, enhanced ROS generation and MMP loss after H(2)O(2) exposure, but extrinsic catalase supply rescued them. Overexpression of XBP1 recovered catalase expression in XBP1-deficient cells and diminished ROS generation after H(2)O(2) exposure. Mutation analysis of the catalase promoter region suggests a pivotal role of CCAAT boxes, NF-Y-binding sites, for the XBP1-mediated enhancing effect. Taken together, these results indicate a protective role of XBP1 against oxidative stress, and its positive regulation of catalase expression may at least in part account for this function.
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