Protein arginylation is regulated during SARS-CoV-2 infection

In 2019, the world witnessed the onset of an unprecedented pandemic. In September 2021, the infection by SARS-CoV-2 had already been responsible for the death of more than 4 million people worldwide. Recently, we and other groups discovered that SARS-CoV-2 infection induces ER-stress and activation of unfolded protein response (UPR) pathway. The degradation of misfolded/unfolded proteins is an essential element of proteostasis and occurs mainly in lysosomes or proteasomes. The N-terminal arginylation of proteins is characterized as an inducer of ubiquitination and proteasomal degradation by the N-end rule pathway. Here we present, for the first time, data on the role of arginylation during SARS-CoV-2 infection. We studied the modulation of protein arginylation in Vero CCL-81 and Calu-3 cells infected after 2h, 6h, 12h, 24h, and 48h. A reanalysis of in vivo and in vitro public omics data combined with immunoblotting was performed to measure the levels of ATE1 and arginylated proteins. This regulation is seen specifically during infections by coronaviruses. We demonstrate that during SARS-CoV-2 infection there is an increase in the expression of the ATE1 enzyme associated with regulated levels of specific arginylated proteins. On the other hand, infected macrophages showed no ATE1 regulation. An important finding revealed that modulation of the N-end rule pathway differs between different types of infected cells. We also confirmed the potential of tannic acid to reduce viral load, and furthermore, to modulate ATE1 levels during infection. In addition, the arginylation inhibitor merbromin (MER) is also capable of both reducing viral load and reducing ATE1 levels. Taken together, these data show the importance of arginylation during the progression of SARS-CoV-2 infection and open the door for future studies that may unravel the role of ATE1 and its inhibitors in pathogen infection.

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The role of unfolded protein response and ER-phagy in quantum dots-induced nephrotoxicity: an in vitro and in vivo study

Archives of Toxicology ◽

10.1007/s00204-018-2169-0 ◽

2018 ◽

Vol 92 (4) ◽

pp. 1421-1434 ◽

Cited By ~ 19

Author(s):

Shengwei Jiang ◽

Yuchun Lin ◽

Huan Yao ◽

Chuanli Yang ◽

Liyin Zhang ◽

...

Keyword(s):

Quantum Dots ◽

Unfolded Protein Response ◽

In Vivo Study ◽

Unfolded Protein ◽

Protein Response

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Transcriptional role of p53 in interferon-mediated antiviral immunity

Journal of Experimental Medicine ◽

10.1084/jem.20080383 ◽

2008 ◽

Vol 205 (8) ◽

pp. 1929-1938 ◽

Cited By ~ 130

Author(s):

César Muñoz-Fontela ◽

Salvador Macip ◽

Luis Martínez-Sobrido ◽

Lauren Brown ◽

Joseph Ashour ◽

...

Keyword(s):

Tumor Suppressor ◽

Viral Replication ◽

Viral Infections ◽

Suppressor Gene ◽

Central Component ◽

Type I ◽

Infected Cells

Tumor suppressor p53 is activated by several stimuli, including DNA damage and oncogenic stress. Previous studies (Takaoka, A., S. Hayakawa, H. Yanai, D. Stoiber, H. Negishi, H. Kikuchi, S. Sasaki, K. Imai, T. Shibue, K. Honda, and T. Taniguchi. 2003. Nature. 424:516–523) have shown that p53 is also induced in response to viral infections as a downstream transcriptional target of type I interferon (IFN) signaling. Moreover, many viruses, including SV40, human papillomavirus, Kaposi's sarcoma herpesvirus, adenoviruses, and even RNA viruses such as polioviruses, have evolved mechanisms designated to abrogate p53 responses. We describe a novel p53 function in the activation of the IFN pathway. We observed that infected mouse and human cells with functional p53 exhibited markedly decreased viral replication early after infection. This early inhibition of viral replication was mediated both in vitro and in vivo by a p53-dependent enhancement of IFN signaling, specifically the induction of genes containing IFN-stimulated response elements. Of note, p53 also contributed to an increase in IFN release from infected cells. We established that this p53-dependent enhancement of IFN signaling is dependent to a great extent on the ability of p53 to activate the transcription of IFN regulatory factor 9, a central component of the IFN-stimulated gene factor 3 complex. Our results demonstrate that p53 contributes to innate immunity by enhancing IFN-dependent antiviral activity independent of its functions as a proapoptotic and tumor suppressor gene.

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Copper complexes as antitumor agents: in vitro and in vivo evidences

Current Medicinal Chemistry ◽

10.2174/0929867328666211117094550 ◽

2021 ◽

Vol 28 ◽

Author(s):

Lucia M. Balsa ◽

Enrique J. Baran ◽

Ignacio E. León

Keyword(s):

Copper Complexes ◽

Antitumor Agents ◽

Essential Element ◽

Design Synthesis ◽

Copper Compounds ◽

Comprehensive Knowledge ◽

The Relationship

: Copper is an essential element for most aerobic organisms, with an important function as a structural and catalytic cofactor, and in consequence, it is implicated in several biological actions. The relevant aspects of chemistry and biochemistry and the importance of copper compounds in medicine give us a comprehensive knowledge of the multifaceted applications of copper in physiology and physiopathology. In this review, we present an outline of the chemistry and the antitumor properties of copper complexes on breast, colon, and lung cancer cells focus on the role of copper in cancer, the relationship between structure-activity, molecular targets, and the study of the mechanism of action involved in its anticancer activity. This overview is expected to contribute to understanding the design, synthesis, uses of copper complexes as antitumor agents in the most common cancers.

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USP19 deubiquitinating enzyme inhibits muscle cell differentiation by suppressing unfolded-protein response signaling

Molecular Biology of the Cell ◽

10.1091/mbc.e14-06-1129 ◽

2015 ◽

Vol 26 (5) ◽

pp. 913-923 ◽

Cited By ~ 18

Author(s):

Benjamin Wiles ◽

Miao Miao ◽

Erin Coyne ◽

Louise Larose ◽

Andrey V. Cybulsky ◽

...

Keyword(s):

Cell Differentiation ◽

Unfolded Protein Response ◽

Muscle Cell ◽

Deubiquitinating Enzyme ◽

Muscle Cell Differentiation ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

USP19 deubiquitinating enzyme has two isoforms, cytoplasmic and endoplasmic reticulum (ER) localized. The ER-localized isoform specifically suppresses muscle cell differentiation in vitro and appears to do so by inhibiting the unfolded-protein response that occurs during such differentiation. In vivo, loss of USP19 promotes muscle regeneration following injury.

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Pentoxifylline Attenuates Methionine- and Choline-Deficient-Diet-Induced Steatohepatitis by Suppressing TNF-αExpression and Endoplasmic Reticulum Stress

Experimental Diabetes Research ◽

10.1155/2012/762565 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 13

Author(s):

Min Kyung Chae ◽

Sang Gyu Park ◽

Sun-Ok Song ◽

Eun Seok Kang ◽

Bong Soo Cha ◽

...

Keyword(s):

Er Stress ◽

Deficient Diet ◽

Group Iii ◽

Unfolded Protein ◽

Sd Rats ◽

Group I ◽

Hep3b Cells ◽

Protein Response

Background. Pentoxifylline (PTX) anti-TNF properties are known to exert hepatoprotective effects in various liver injury models. The aim of this study was to investigate whether PTX has beneficial roles in the development of methionine- and choline-deficient-(MCD-) diet-induced NAFLD SD ratsin vivoand TNF-α-induced Hep3B cellsin vitro.Methods. SD Rats were classified according to diet (chow or MCD diet) and treatment (normal saline or PTX injection) over a period of 4 weeks: group I (chow + saline,n=4), group II (chow + PTX), group III (MCD + saline), and group IV (MCD + PTX). Hep3B cells were treated with 100 ng/ml TNF-α(24 h) in the absence or presence of PTX (1 mM).Results. PTX attenuated MCD-diet-induced serum ALT levels and hepatic steatosis. In real-time PCR and western blotting analysis, PTX decreased MCD-diet-induced TNF-alpha mRNA expression and proapoptotic unfolded protein response by ER stress (GRP78, p-eIF2, ATF4, IRE1α, CHOP, and p-JNK activation)in vivo. PTX (1 mM) reduced TNF-α-induced activation of GRP78, p-eIF2, ATF4, IRE1α, and CHOPin vitro.Conclusion. PTX has beneficial roles in the development of MCD-diet-induced steatohepatitis through partial suppression of TNF-αand ER stress.

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Regulation of Impaired Protein Kinase C Signaling by Chemokines in Murine Macrophages during Visceral Leishmaniasis

Infection and Immunity ◽

10.1128/iai.73.12.8334-8344.2005 ◽

2005 ◽

Vol 73 (12) ◽

pp. 8334-8344 ◽

Cited By ~ 22

Author(s):

Ranadhir Dey ◽

Arup Sarkar ◽

Nivedita Majumder ◽

Suchandra Bhattacharyya (Majumdar) ◽

Kaushik Roychoudhury ◽

...

Keyword(s):

Protein Kinase C ◽

Protein Kinase ◽

Leishmania Donovani ◽

Disease Process ◽

Kinase C ◽

Parasitic Burden ◽

Infected Cells

ABSTRACT The protein kinase C (PKC) family regulates macrophage function involved in host defense against infection. In the case of Leishmania donovani infection, the impairment of PKC-mediated signaling is one of the crucial events for the establishment of parasite into the macrophages. Earlier reports established that C-C chemokines mediated protection against leishmaniasis via the generation of nitric oxide after 48 h. In this study, we investigated the role of MIP-1α and MCP-1 in the regulation of impaired PKC activity in the early hours (6 h) of infection. These chemokines restored Ca2+-dependent PKC activity and inhibited Ca2+-independent atypical PKC activity in L. donovani-infected macrophages under both in vivo and in vitro conditions. Pretreatment of macrophages with chemokines induced superoxide anion generation by activating NADPH oxidase components in infected cells. Chemokine administration in vitro induced the migration of infected macrophages and triggered the production of reactive oxygen species. In vivo treatment with chemokines significantly restricted the parasitic burden in livers as well as in spleens. Collectively, these results indicate a novel regulatory role of C-C chemokines in controlling the intracellular growth and multiplication of L. donovani, thereby demonstrating the antileishmanial properties of C-C chemokines in the disease process.

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A Novel Transcription Factor, ERD15 (Early Responsive to Dehydration 15), Connects Endoplasmic Reticulum Stress with an Osmotic Stress-induced Cell Death Signal

Journal of Biological Chemistry ◽

10.1074/jbc.m111.233494 ◽

2011 ◽

Vol 286 (22) ◽

pp. 20020-20030 ◽

Cited By ~ 29

Author(s):

Murilo S. Alves ◽

Pedro A. B. Reis ◽

Silvana P. Dadalto ◽

Jerusa A. Q. A. Faria ◽

Elizabeth P. B. Fontes ◽

...

Keyword(s):

Endoplasmic Reticulum ◽

Cell Death ◽

Transcription Factor ◽

Osmotic Stress ◽

Er Stress ◽

Unfolded Protein ◽

Eukaryotic Organisms ◽

Protein Response

As in all other eukaryotic organisms, endoplasmic reticulum (ER) stress triggers the evolutionarily conserved unfolded protein response in soybean, but it also communicates with other adaptive signaling responses, such as osmotic stress-induced and ER stress-induced programmed cell death. These two signaling pathways converge at the level of gene transcription to activate an integrated cascade that is mediated by N-rich proteins (NRPs). Here, we describe a novel transcription factor, GmERD15 (Glycine max Early Responsive to Dehydration 15), which is induced by ER stress and osmotic stress to activate the expression of NRP genes. GmERD15 was isolated because of its capacity to stably associate with the NRP-B promoter in yeast. It specifically binds to a 187-bp fragment of the NRP-B promoter in vitro and activates the transcription of a reporter gene in yeast. Furthermore, GmERD15 was found in both the cytoplasm and the nucleus, and a ChIP assay revealed that it binds to the NRP-B promoter in vivo. Expression of GmERD15 in soybean protoplasts activated the NRP-B promoter and induced expression of the NRP-B gene. Collectively, these results support the interpretation that GmERD15 functions as an upstream component of stress-induced NRP-B-mediated signaling to connect stress in the ER to an osmotic stress-induced cell death signal.

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Activation of the Unfolded Protein Response with the First-in-Class P97 Inhibitor CB-5083 Induces Stable Disease Regression and Overcomes Ara-C Resistance in AML

Blood ◽

10.1182/blood.v126.23.1350.1350 ◽

2015 ◽

Vol 126 (23) ◽

pp. 1350-1350

Author(s):

Steffan T. Nawrocki ◽

Yingchun Han ◽

Ronan LE Moigne ◽

Valeria Visconte ◽

Bartlomiej Przychodzen ◽

...

Keyword(s):

Unfolded Protein Response ◽

Board Of Directors ◽

Cell Lines ◽

Primary Cells ◽

Advisory Committees ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

Abstract Acute myeloid leukemia (AML) therapy has remained relatively unchanged for more than 40 years with the majority of patients not achieving long-term remission when treated with currently available agents. Novel strategies are urgently needed to improve outcomes. The constitutive dysregulation of protein synthesis/turnover contributes to disease progression and drug resistance in many forms of cancer including AML. p97 (VCP) is a master regulator of protein turnover that has been implicated in oncogenesis and malignant pathogenesis. CB-5083 is a first-in-class selective and potent orally available inhibitor of p97 that in currently being evaluated in phase I clinical trials in patients with multiple myeloma and advanced solid tumors. To assess the potential benefit of p97 inhibition as a novel approach for AML therapy, we investigated the efficacy, pharmacodynamics (PD), and pharmacokinetics (PK) of CB-5083 in a panel of human AML cell lines with diverse genetic backgrounds, primary AML specimens from both newly diagnosed and relapsed/refractory patients, and xenograft mouse models of AML. In vitro treatment with CB-5083 potently diminished the viability of AML cell lines (n = 7) and primary CD34+ blasts obtained from patients (n = 10) with IC50s significantly below 1 µM (range 200 - 700 nM) in all lines and specimens evaluated to date. Diminished viability was associated with reduced clonogenic survival and increased apoptosis in AML cell lines and primary blasts. In contrast to many conventional and experimental drugs that are less active against primary AML cells than established AML cell lines, primary cells exhibited sensitivity to CB-5083 that was similar to cell lines. Additionally, CB-5083 was highly active in 3 different cell line models of cytarabine resistance and primary cells from refractory AML patients. This suggests that CB-5083 may be effective for patients who are relapsed/refractory to conventional therapy. In vitro PD analyses demonstrated that CB-5083 rapidly triggered the accumulation of ubiquitin-conjugated proteins, activated the unfolded protein response (UPR), disrupted STAT5 signaling, reduced levels of key STAT5 targets including BCL-xL and PIM-2, and induced apoptosis. The pro-apoptotic effects of CB-5083 were associated with activation of the endoplasmic reticulum (ER) resident initiator caspase-4 and induction of the BH3-only protein NOXA, which has been previously demonstrated to be an important mediator of cell death induced by other agents that disrupt protein homeostasis. RNA sequencing (RNASeq) gene ontology (GO) analyses of MV4-11 and MOLM-13 AML cells following treatment with CB-5083 demonstrated that short-term treatment (6h) caused significant increases in multiple regulators of the unfolded protein response, protein biosynthesis, and other ubiquitin-related pathways (p<0.001). Results were confirmed by qRT-PCR. The in vivo anti-leukemic activity of CB-5083 was investigated in two different xenograft mouse models of AML: the FLT3-ITD+ MV4-11 cell line and APML HL-60 cells. Oral administration of CB-5083 (once daily, 4 days on, 3 days off) was well tolerated and induced disease regression in both xenograft models (p<0.01). In vivo PD studies demonstrated that administration of CB-5083 led to reduced AML cell proliferation (PCNA), to the induction of apoptosis (active caspase-3), and pathway inhibition as evidenced by poly-ubiquitin accumulation and elevated expression of CHOP, GRP78, and NOXA. PK-PD analyses demonstrated a correlation between the kinetics of the in vivo PD effects and drug exposure. Our collective preclinical data demonstrate that p97 inhibition is a very effective novel anti-leukemic strategy and support clinical investigation of CB-5083 in patients with relapsed/refractory AML. Disclosures LE Moigne: Cleave Biosciences: Employment. Rolfe:Cleave Biosciences: Employment. Djakovic:Cleave Biosciences: Employment. Anderson:Cleave Biosciences: Employment. Wustrow:Cleave Biosciences: Employment. Zhou:Cleave Biosciences: Employment. Wong:Cleave Biosciences: Employment. Sekeres:TetraLogic: Membership on an entity's Board of Directors or advisory committees; Celgene Corporation: Membership on an entity's Board of Directors or advisory committees; Amgen: Membership on an entity's Board of Directors or advisory committees. Carew:Boehringer Ingelheim: Research Funding.

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Leukemia-Associated HSC Vascular Niche Is Negatively Regulated By PERK of Unfolded Protein Response (UPR)

Blood ◽

10.1182/blood-2019-127607 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 2486-2486

Author(s):

Lan Zhou ◽

Cui Liu ◽

Stanley A Adoro ◽

Lechuang Chen ◽

Diana Ramirez ◽

...

Keyword(s):

Bone Marrow ◽

Endothelial Cells ◽

Er Stress ◽

Leukemia Cell ◽

Unfolded Protein ◽

Vascular Niche ◽

Activating Transcription Factor ◽

Protein Response

T cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematological malignancy derived from early T cell progenitors. Diffuse infiltration of the bone marrow by T-ALL is associated with worse prognosis. We previously reported that actively proliferating leukemia cells inhibit normal hematopoietic stem and progenitor cell (HSPC) proliferation and homing to the perivascular region. We found that aberrant Notch activation in the stroma plays an important role in negatively regulating the expression of CXLC12 on osteoblasts and their differentiation. However, the underlying molecular mechanism that leads to the suppression of hematopoiesis and decreased HSPC in the vascular niche is unclear. It has been demonstrated that rapid cellular proliferation associated with oncogenic activity such as MYC in T-ALL leads to a global increase in protein synthesis and an increase in misfolded/unfolded polypeptides in the endoplasmic reticulum (ER), referred to as unfolded protein response (UPR) or ER stress. Elevated ER stress leads to activation of at least three types of ER stress transducers through the release of inhibitory binding by glucose-regulated chaperone protein (GRP78/BIP): the protein kinase RNA-like ER kinase (PERK), the inositol-requiring enzyme 1 (IRE1), and the activating transcription factor 6 (ATF6). Activation of PERK phosphorylates eIF2 to repress global translation with the exception of a small number of proteins including ATF4 (activating transcription factor-4). ATF4 regulates genes involved in restoring ER homeostasis and genes in apoptosis. Here, we studied the role of UPR in the regulation of HSC niche function in the setting of T-ALL progression. Using in vitro assays in which T-ALL leukemia cells driven by activated Notch1 (ICN1) were co-cultured with endothelial cells (MILE SVEN 1, MS1), and in vivo ICN1-driven T-ALL model, we found that PERK-eIF2a-ATF4 pathway was activated in both MS1 cells and BM endothelial cells isolated from T-ALL mice, while IRE1 and ATF6 pathways were only mildly altered. The activation of PERK was accompanied with the increased expression of Jagged1 and suppressed expression of CXCL12 in both cultured endothelial cells and bone marrow endothelial cells from leukemia mice. PERK inhibitor (GSK2606414) treatment of co-cultured cells largely restored CXCL12 expression, which was also negatively regulated by Jagged1, and accelerated the leukemia cell apoptosis as indicated by the enhanced annexin staining. These findings suggest that PERK is the upstream regulator of Jagged1 and CXCL12 in the endothelial cells; however, the function of cell-autonomous PERK on leukemia cell survival needs to be further clarified. To understand the role of PERK in bone marrow endothelium during leukemia development in vivo, we examined T-ALL leukemia progression and its effect on vascular niche function in VE-CadherinERT2/PERKF/F mice in which Perk was specifically deleted in endothelial cells. Consistent with in vitro findings, T-ALL development induced endothelial PERK-eIF2a-ATF4 activation, while up-regulated Jagged1 and down-regulated CXCL12 were also identified in isolated BM endothelial cells. Compared to the wild type mice, VE-CadherinERT2/PERKF/F mice showed attenuated leukemia progression, increased HSPC (Lin-Sca-1+c-kit+) frequency, and improved survival. Taken together, our findings suggest that PERK activation in BM endothelial cells is a key regulator of the leukemia vascular niche to promote leukemia progression and to suppress normal hematopoiesis. Therefore, targeting PERK may offer an effective strategy in restoring normal HSPC homeostasis and limiting leukemia progression. Disclosures No relevant conflicts of interest to declare.

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Unfolded Protein Response and Crohn’s Diseases: A Molecular Mechanism of Wound Healing in the Gut

10.20944/preprints202012.0578.v2 ◽

2021 ◽

Author(s):

Chao Li

Keyword(s):

Er Stress ◽

Unfolded Protein Response ◽

Immune Cell ◽

Macrophage Polarization ◽

Intestinal Epithelial ◽

Unfolded Protein ◽

The Unfolded Protein Response ◽

Protein Response

Endoplasmic reticulum (ER) stress triggers a series of signaling and transcriptional events termed the unfolded protein response (UPR). Severe ER stress is associated with the development of fibrosis in different organs including lung, liver, kidney, heart, and intestine. ER stress is an essential response of epithelial and immune cells in the pathogenesis of inflammatory bowel disease (IBD) including Crohn’s disease. Intestinal epithelial cells are susceptible to ER stress-mediated damage due to secretion of a large amount of proteins that are involved in mucosal defense. In other cells, ER stress is linked to myofibroblast activation, extracellular matrix production, macrophage polarization, and immune cell differentiation. This review focuses on the role of UPR in the pathogenesis in IBD from an immunologic perspective. The roles of macrophage and mesenchymal cells in the UPR from in vitro and in vivo animal models are discussed. The links between ER stress and other signaling pathways such as senescence and autophagy are introduced. Recent advances in the understanding of the epigenetic regulation of UPR signaling are also updated here. The future directions of development of the UPR research and therapeutic strategies to manipulate ER stress levels are also reviewed.

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