1
|
Smirnova AM, Hronova V, Mohammad MP, Herrmannova A, Gunisova S, Petrackova D, Halada P, Coufal S, Swirski M, Rendelman J, Jendruchova K, Hatzoglou M, Beznoskova P, Vogel C, Valasek LS. Stem-loop induced ribosome queuing in the uORF2/ATF4 overlap fine-tunes stress-induced human ATF4 translational control. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.07.12.548609. [PMID: 37502919 PMCID: PMC10369994 DOI: 10.1101/2023.07.12.548609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/29/2023]
Abstract
ATF4 is a master transcriptional regulator of the integrated stress response leading cells towards adaptation or death. ATF4's induction under stress was thought to be mostly due to delayed translation reinitiation, where the reinitiation-permissive uORF1 plays a key role. Accumulating evidence challenging this mechanism as the sole source of ATF4 translation control prompted us to investigate additional regulatory routes. We identified a highly conserved stem-loop in the uORF2/ATF4 overlap, immediately preceded by a near-cognate CUG, which introduces another layer of regulation in the form of ribosome queuing. These elements explain how the inhibitory uORF2 can be translated under stress, confirming prior observations, but contradicting the original regulatory model. We also identified two highly conserved, potentially modified adenines performing antagonistic roles. Finally, we demonstrate that the canonical ATF4 translation start site is substantially leaky-scanned. Thus, ATF4's translational control is more complex than originally described underpinning its key role in diverse biological processes.
Collapse
|
2
|
Zhang SX, Wang JJ, Starr CR, Lee EJ, Park KS, Zhylkibayev A, Medina A, Lin JH, Gorbatyuk M. The endoplasmic reticulum: Homeostasis and crosstalk in retinal health and disease. Prog Retin Eye Res 2024; 98:101231. [PMID: 38092262 PMCID: PMC11056313 DOI: 10.1016/j.preteyeres.2023.101231] [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: 08/21/2023] [Revised: 12/05/2023] [Accepted: 12/06/2023] [Indexed: 12/19/2023]
Abstract
The endoplasmic reticulum (ER) is the largest intracellular organelle carrying out a broad range of important cellular functions including protein biosynthesis, folding, and trafficking, lipid and sterol biosynthesis, carbohydrate metabolism, and calcium storage and gated release. In addition, the ER makes close contact with multiple intracellular organelles such as mitochondria and the plasma membrane to actively regulate the biogenesis, remodeling, and function of these organelles. Therefore, maintaining a homeostatic and functional ER is critical for the survival and function of cells. This vital process is implemented through well-orchestrated signaling pathways of the unfolded protein response (UPR). The UPR is activated when misfolded or unfolded proteins accumulate in the ER, a condition known as ER stress, and functions to restore ER homeostasis thus promoting cell survival. However, prolonged activation or dysregulation of the UPR can lead to cell death and other detrimental events such as inflammation and oxidative stress; these processes are implicated in the pathogenesis of many human diseases including retinal disorders. In this review manuscript, we discuss the unique features of the ER and ER stress signaling in the retina and retinal neurons and describe recent advances in the research to uncover the role of ER stress signaling in neurodegenerative retinal diseases including age-related macular degeneration, inherited retinal degeneration, achromatopsia and cone diseases, and diabetic retinopathy. In some chapters, we highlight the complex interactions between the ER and other intracellular organelles focusing on mitochondria and illustrate how ER stress signaling regulates common cellular stress pathways such as autophagy. We also touch upon the integrated stress response in retinal degeneration and diabetic retinopathy. Finally, we provide an update on the current development of pharmacological agents targeting the UPR response and discuss some unresolved questions and knowledge gaps to be addressed by future research.
Collapse
Affiliation(s)
- Sarah X Zhang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States; Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States.
| | - Josh J Wang
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Christopher R Starr
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Eun-Jin Lee
- Department of Ophthalmology and Byers Eye Institute, Stanford University, Stanford, CA, United States; VA Palo Alto Healthcare System, Palo Alto, CA, United States; Department of Pathology, Stanford University, Stanford, CA, United States
| | - Karen Sophia Park
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Assylbek Zhylkibayev
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Andy Medina
- Department of Ophthalmology and Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, United States
| | - Jonathan H Lin
- Department of Ophthalmology and Byers Eye Institute, Stanford University, Stanford, CA, United States; VA Palo Alto Healthcare System, Palo Alto, CA, United States; Department of Pathology, Stanford University, Stanford, CA, United States
| | - Marina Gorbatyuk
- Department of Optometry and Vision Science, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
3
|
Tripathi A, Iyer K, Mitra D. HIV-1 replication requires optimal activation of the unfolded protein response. FEBS Lett 2023; 597:2908-2930. [PMID: 37984889 DOI: 10.1002/1873-3468.14772] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/16/2023] [Accepted: 10/29/2023] [Indexed: 11/22/2023]
Abstract
Several human diseases including viral infections activate the unfolded protein response (UPR) due to abnormal accumulation of unfolded/misfolded proteins. However, UPR modulation and its functional relevance in HIV-1 infection lack comprehensive elucidation. This study reveals that HIV-1 activates IRE1, PERK, and ATF6 signaling pathways of UPR. The knockdown of PERK and ATF6 reduces HIV-1 long terminal repeat (LTR)-driven gene expression, whereas the endoplasmic reticulum (ER) chaperone HSPA5 prevents proteasomal degradation of HIV-1 p24 through its chaperone activity. Interestingly, overstimulation of UPR by a chemical inducer leads to anti-HIV activity through an enhanced type-1 interferon response. Also, treatment with a chemical ER stress inhibitor reduces HIV-1 replication. These findings suggest that an optimal UPR activation is crucial for effective viral replication, as either overstimulating UPR or inhibiting ER stress leads to viral suppression.
Collapse
|
4
|
Xiang J, Pompetti AJ, Faranda AP, Wang Y, Novo SG, Li DWC, Duncan MK. ATF4 May Be Essential for Adaption of the Ocular Lens to Its Avascular Environment. Cells 2023; 12:2636. [PMID: 37998373 PMCID: PMC10670291 DOI: 10.3390/cells12222636] [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: 03/23/2023] [Revised: 10/30/2023] [Accepted: 11/03/2023] [Indexed: 11/25/2023] Open
Abstract
The late embryonic mouse lens requires the transcription factor ATF4 for its survival although the underlying mechanisms were unknown. Here, RNAseq analysis revealed that E16.5 Atf4 null mouse lenses downregulate the mRNA levels of lens epithelial markers as well as known markers of late lens fiber cell differentiation. However, a comparison of this list of differentially expressed genes (DEGs) with other known transcriptional regulators of lens development indicated that ATF4 expression is not directly controlled by the previously described lens gene regulatory network. Pathway analysis revealed that the Atf4 DEG list was enriched in numerous genes involved in nutrient transport, amino acid biosynthesis, and tRNA charging. These changes in gene expression likely result in the observed reductions in lens free amino acid and glutathione levels, which would result in the observed low levels of extractable lens protein, finally leading to perinatal lens disintegration. These data demonstrate that ATF4, via its function in the integrated stress response, is likely to play a crucial role in mediating the adaption of the lens to the avascularity needed to maintain lens transparency.
Collapse
Affiliation(s)
- Jiawen Xiang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510230, China
| | - Anthony J. Pompetti
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Adam P. Faranda
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Samuel G. Novo
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - David Wan-Cheng Li
- The State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510230, China
| | - Melinda K. Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| |
Collapse
|
5
|
Brünnert D, Seupel R, Goyal P, Bach M, Schraud H, Kirner S, Köster E, Feineis D, Bargou RC, Schlosser A, Bringmann G, Chatterjee M. Ancistrocladinium A Induces Apoptosis in Proteasome Inhibitor-Resistant Multiple Myeloma Cells: A Promising Therapeutic Agent Candidate. Pharmaceuticals (Basel) 2023; 16:1181. [PMID: 37631095 PMCID: PMC10459547 DOI: 10.3390/ph16081181] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/11/2023] [Accepted: 08/16/2023] [Indexed: 08/27/2023] Open
Abstract
The N,C-coupled naphthylisoquinoline alkaloid ancistrocladinium A belongs to a novel class of natural products with potent antiprotozoal activity. Its effects on tumor cells, however, have not yet been explored. We demonstrate the antitumor activity of ancistrocladinium A in multiple myeloma (MM), a yet incurable blood cancer that represents a model disease for adaptation to proteotoxic stress. Viability assays showed a potent apoptosis-inducing effect of ancistrocladinium A in MM cell lines, including those with proteasome inhibitor (PI) resistance, and in primary MM cells, but not in non-malignant blood cells. Concomitant treatment with the PI carfilzomib or the histone deacetylase inhibitor panobinostat strongly enhanced the ancistrocladinium A-induced apoptosis. Mass spectrometry with biotinylated ancistrocladinium A revealed significant enrichment of RNA-splicing-associated proteins. Affected RNA-splicing-associated pathways included genes involved in proteotoxic stress response, such as PSMB5-associated genes and the heat shock proteins HSP90 and HSP70. Furthermore, we found strong induction of ATF4 and the ATM/H2AX pathway, both of which are critically involved in the integrated cellular response following proteotoxic and oxidative stress. Taken together, our data indicate that ancistrocladinium A targets cellular stress regulation in MM and improves the therapeutic response to PIs or overcomes PI resistance, and thus may represent a promising potential therapeutic agent.
Collapse
Affiliation(s)
- Daniela Brünnert
- University Hospital of Würzburg, Comprehensive Cancer Center Mainfranken, Translational Oncology, 97080 Würzburg, Germany (M.C.)
| | - Raina Seupel
- Institute of Organic Chemistry, University of Würzburg, 97074 Würzburg, Germany
| | - Pankaj Goyal
- Department of Biotechnology, School of Life Sciences, Central University of Rajasthan, Bandar Sindri, Kishangarh 305817, India;
| | - Matthias Bach
- Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, 97080 Würzburg, Germany
| | - Heike Schraud
- University Hospital of Würzburg, Comprehensive Cancer Center Mainfranken, Translational Oncology, 97080 Würzburg, Germany (M.C.)
| | - Stefanie Kirner
- University Hospital of Würzburg, Comprehensive Cancer Center Mainfranken, Translational Oncology, 97080 Würzburg, Germany (M.C.)
| | - Eva Köster
- Institute of Organic Chemistry, University of Würzburg, 97074 Würzburg, Germany
| | - Doris Feineis
- Institute of Organic Chemistry, University of Würzburg, 97074 Würzburg, Germany
| | - Ralf C. Bargou
- University Hospital of Würzburg, Comprehensive Cancer Center Mainfranken, Translational Oncology, 97080 Würzburg, Germany (M.C.)
| | - Andreas Schlosser
- Rudolf Virchow Center for Experimental Biomedicine, University of Würzburg, 97080 Würzburg, Germany
| | - Gerhard Bringmann
- Institute of Organic Chemistry, University of Würzburg, 97074 Würzburg, Germany
| | - Manik Chatterjee
- University Hospital of Würzburg, Comprehensive Cancer Center Mainfranken, Translational Oncology, 97080 Würzburg, Germany (M.C.)
| |
Collapse
|
6
|
Chaperone-Dependent Mechanisms as a Pharmacological Target for Neuroprotection. Int J Mol Sci 2023; 24:ijms24010823. [PMID: 36614266 PMCID: PMC9820882 DOI: 10.3390/ijms24010823] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 12/26/2022] [Accepted: 12/27/2022] [Indexed: 01/05/2023] Open
Abstract
Modern pharmacotherapy of neurodegenerative diseases is predominantly symptomatic and does not allow vicious circles causing disease development to break. Protein misfolding is considered the most important pathogenetic factor of neurodegenerative diseases. Physiological mechanisms related to the function of chaperones, which contribute to the restoration of native conformation of functionally important proteins, evolved evolutionarily. These mechanisms can be considered promising for pharmacological regulation. Therefore, the aim of this review was to analyze the mechanisms of endoplasmic reticulum stress (ER stress) and unfolded protein response (UPR) in the pathogenesis of neurodegenerative diseases. Data on BiP and Sigma1R chaperones in clinical and experimental studies of Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, and Huntington's disease are presented. The possibility of neuroprotective effect dependent on Sigma1R ligand activation in these diseases is also demonstrated. The interaction between Sigma1R and BiP-associated signaling in the neuroprotection is discussed. The performed analysis suggests the feasibility of pharmacological regulation of chaperone function, possibility of ligand activation of Sigma1R in order to achieve a neuroprotective effect, and the need for further studies of the conjugation of cellular mechanisms controlled by Sigma1R and BiP chaperones.
Collapse
|
7
|
Xiao W, Sun Y, Xu J, Zhang N, Dong L. uORF-Mediated Translational Regulation of ATF4 Serves as an Evolutionarily Conserved Mechanism Contributing to Non-Small-Cell Lung Cancer (NSCLC) and Stress Response. J Mol Evol 2022; 90:375-388. [PMID: 35962830 PMCID: PMC9375200 DOI: 10.1007/s00239-022-10068-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Accepted: 07/20/2022] [Indexed: 11/30/2022]
Abstract
Diseases and environmental stresses are two distinct challenges for virtually all living organisms. In light of evolution, cellular responses to diseases and stresses might share similar molecular mechanisms, but the detailed regulation pathway is not reported yet. We obtained the transcriptomes and translatomes from several NSCLC (non-small-cell lung cancer) patients as well as from different species under normal or stress conditions. We found that the translation level of gene ATF4 is remarkably enhanced in NSCLC due to the reduced number of ribosomes binding to its upstream open reading frames (uORFs). We also showed the evolutionary conservation of this uORF-ATF4 regulation in the stress response of other species. Molecular experiments showed that knockdown of ATF4 reduced the cell growth rate while overexpression of ATF4 enhanced cell growth, especially for the ATF4 allele with mutated uORFs. Population genetics analyses in multiple species verified that the mutations that abolish uATGs (start codon of uORFs) are highly deleterious, suggesting the functional importance of uORFs. Our study proposes an evolutionarily conserved pattern that enhances the ATF4 translation by uORFs upon stress or disease. We generalized the concept of cellular response to diseases and stresses. These two biological processes may share similar molecular mechanisms.
Collapse
Affiliation(s)
- Wenjing Xiao
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
| | - Yang Sun
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Jinpeng Xu
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Na Zhang
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| | - Lina Dong
- Department of Radiotherapy, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China
| |
Collapse
|
8
|
Szewczyk MM, Luciani GM, Vu V, Murison A, Dilworth D, Barghout SH, Lupien M, Arrowsmith CH, Minden MD, Barsyte-Lovejoy D. PRMT5 regulates ATF4 transcript splicing and oxidative stress response. Redox Biol 2022; 51:102282. [PMID: 35305370 PMCID: PMC8933703 DOI: 10.1016/j.redox.2022.102282] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 02/18/2022] [Accepted: 03/08/2022] [Indexed: 02/07/2023] Open
Abstract
Protein methyltransferase 5 (PRMT5) symmetrically dimethylates arginine residues leading to regulation of transcription and splicing programs. Although PRMT5 has emerged as an attractive oncology target, the molecular determinants of PRMT5 dependency in cancer remain incompletely understood. Our transcriptomic analysis identified PRMT5 regulation of the activating transcription factor 4 (ATF4) pathway in acute myelogenous leukemia (AML). PRMT5 inhibition resulted in the expression of unstable, intron-retaining ATF4 mRNA that is detained in the nucleus. Concurrently, the decrease in the spliced cytoplasmic transcript of ATF4 led to lower levels of ATF4 protein and downregulation of ATF4 target genes. Upon loss of functional PRMT5, cells with low ATF4 displayed increased oxidative stress, growth arrest, and cellular senescence. Interestingly, leukemia cells with EVI1 oncogene overexpression demonstrated dependence on PRMT5 function. EVI1 and ATF4 regulated gene signatures were inversely correlated. We show that EVI1-high AML cells have reduced ATF4 levels, elevated baseline reactive oxygen species and increased sensitivity to PRMT5 inhibition. Thus, EVI1-high cells demonstrate dependence on PRMT5 function and regulation of oxidative stress response. Overall, our findings identify the PRMT5-ATF4 axis to be safeguarding the cellular redox balance that is especially important in high oxidative stress states, such as those that occur with EVI1 overexpression.
Collapse
Affiliation(s)
| | - Genna M Luciani
- Department of Medical Biophysics, University of Toronto, Ontario, Canada; Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Victoria Vu
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Ontario, Canada
| | - Alex Murison
- Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - David Dilworth
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Samir H Barghout
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada
| | - Mathieu Lupien
- Department of Medical Biophysics, University of Toronto, Ontario, Canada; Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Cheryl H Arrowsmith
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada; Department of Medical Biophysics, University of Toronto, Ontario, Canada; Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Mark D Minden
- Department of Medical Biophysics, University of Toronto, Ontario, Canada; Princess Margaret Cancer Centre, Toronto, Ontario, Canada.
| | - Dalia Barsyte-Lovejoy
- Structural Genomics Consortium, University of Toronto, Toronto, Ontario, Canada; Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, M5S 1A8, Canada.
| |
Collapse
|
9
|
Maity S, Komal P, Kumar V, Saxena A, Tungekar A, Chandrasekar V. Impact of ER Stress and ER-Mitochondrial Crosstalk in Huntington's Disease. Int J Mol Sci 2022; 23:780. [PMID: 35054963 PMCID: PMC8775980 DOI: 10.3390/ijms23020780] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/30/2021] [Accepted: 01/03/2022] [Indexed: 02/07/2023] Open
Abstract
Accumulation of misfolded proteins is a common phenomenon of several neurodegenerative diseases. The misfolding of proteins due to abnormal polyglutamine (PolyQ) expansions are linked to the development of PolyQ diseases including Huntington's disease (HD). Though the genetic basis of PolyQ repeats in HD remains prominent, the primary molecular basis mediated by PolyQ toxicity remains elusive. Accumulation of misfolded proteins in the ER or disruption of ER homeostasis causes ER stress and activates an evolutionarily conserved pathway called Unfolded protein response (UPR). Protein homeostasis disruption at organelle level involving UPR or ER stress response pathways are found to be linked to HD. Due to dynamic intricate connections between ER and mitochondria, proteins at ER-mitochondria contact sites (mitochondria associated ER membranes or MAMs) play a significant role in HD development. The current review aims at highlighting the most updated information about different UPR pathways and their involvement in HD disease progression. Moreover, the role of MAMs in HD progression has also been discussed. In the end, the review has focused on the therapeutic interventions responsible for ameliorating diseased states via modulating either ER stress response proteins or modulating the expression of ER-mitochondrial contact proteins.
Collapse
Affiliation(s)
- Shuvadeep Maity
- Department of Biological Sciences, Birla Institute of Technology and Science (BITS)-Pilani (Hyderabad Campus), Shameerpet-Mandal, Hyderabad 500078, Telangana, India; (P.K.); (V.K.); (A.S.); (A.T.); (V.C.)
| | | | | | | | | | | |
Collapse
|
10
|
Vendramin R, Katopodi V, Cinque S, Konnova A, Knezevic Z, Adnane S, Verheyden Y, Karras P, Demesmaeker E, Bosisio FM, Kucera L, Rozman J, Gladwyn-Ng I, Rizzotto L, Dassi E, Millevoi S, Bechter O, Marine JC, Leucci E. Activation of the integrated stress response confers vulnerability to mitoribosome-targeting antibiotics in melanoma. J Exp Med 2021; 218:e20210571. [PMID: 34287642 PMCID: PMC8424468 DOI: 10.1084/jem.20210571] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Revised: 05/10/2021] [Accepted: 06/16/2021] [Indexed: 12/15/2022] Open
Abstract
The ability to adapt to environmental stress, including therapeutic insult, contributes to tumor evolution and drug resistance. In suboptimal conditions, the integrated stress response (ISR) promotes survival by dampening cytosolic translation. We show that ISR-dependent survival also relies on a concomitant up-regulation of mitochondrial protein synthesis, a vulnerability that can be exploited using mitoribosome-targeting antibiotics. Accordingly, such agents sensitized to MAPK inhibition, thus preventing the development of resistance in BRAFV600E melanoma models. Additionally, this treatment compromised the growth of melanomas that exhibited elevated ISR activity and resistance to both immunotherapy and targeted therapy. In keeping with this, pharmacological inactivation of ISR, or silencing of ATF4, rescued the antitumoral response to the tetracyclines. Moreover, a melanoma patient exposed to doxycycline experienced complete and long-lasting response of a treatment-resistant lesion. Our study indicates that the repurposing of mitoribosome-targeting antibiotics offers a rational salvage strategy for targeted therapy in BRAF mutant melanoma and a therapeutic option for NRAS-driven and immunotherapy-resistant tumors.
Collapse
Affiliation(s)
- Roberto Vendramin
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Vicky Katopodi
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Sonia Cinque
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Angelina Konnova
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Zorica Knezevic
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Sara Adnane
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Yvessa Verheyden
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | - Panagiotis Karras
- Laboratory for Molecular Cancer Biology, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie, Leuven, Belgium
- Department of Oncology, Laboratory for Molecular Cancer Biology, Katholieke Universiteit Leuven, Belgium
| | - Ewout Demesmaeker
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
| | | | - Lukas Kucera
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic
| | - Jan Rozman
- Czech Centre for Phenogenomics, Institute of Molecular Genetics of the Czech Academy of Sciences, Vestec, Czech Republic
| | | | - Lara Rizzotto
- Trace, Leuven Cancer Institute, Katholieke Universiteit Leuven, Belgium
| | - Erik Dassi
- Laboratory of RNA Regulatory Networks, Department of Cellular, Computational and Integrative Biology, University of Trento, Trento, Italy
| | - Stefania Millevoi
- Cancer Research Centre of Toulouse, Institut national de la santé et de la recherche médicale Joint Research Unit 1037, Toulouse, France
- Université Toulouse III Paul Sabatier, Toulouse, France
- Laboratoire d’Excellence “TOUCAN,” Toulouse, France
| | - Oliver Bechter
- Department of General Medical Oncology, Leuven Cancer Institute, Universitair Ziekenhuis Leuven, Leuven, Belgium
| | - Jean-Christophe Marine
- Laboratory for Molecular Cancer Biology, Center for Cancer Biology, Vlaams Instituut voor Biotechnologie, Leuven, Belgium
- Department of Oncology, Laboratory for Molecular Cancer Biology, Katholieke Universiteit Leuven, Belgium
| | - Eleonora Leucci
- Laboratory for RNA Cancer Biology, Department of Oncology, Katholieke Universiteit Leuven, Leuven, Belgium
- Trace, Leuven Cancer Institute, Katholieke Universiteit Leuven, Belgium
| |
Collapse
|
11
|
Chu HS, Peterson C, Jun A, Foster J. Targeting the integrated stress response in ophthalmology. Curr Eye Res 2021; 46:1075-1088. [PMID: 33474991 DOI: 10.1080/02713683.2020.1867748] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Purpose: To summarize the Integrated Stress Response (ISR) in the context of ophthalmology, with special interest on the cornea and anterior segment. Results: The ISR is a powerful and conserved signaling pathway that allows for cells to respond to a diverse array of both intracellular and extracellular stressors. The pathway is classically responsible for coordination of the cellular response to amino acid starvation, ultraviolet light, heme dysregulation, viral infection, and unfolded protein. Under normal circumstances, it is considered pro-survival and a necessary mechanism through which protein translation is controlled. However, in cases of severe or prolonged stress the pathway can promote apoptosis, and loss of normal cellular phenotype. The activation of this pathway culminates in the global inhibition of cap-dependent protein translation and the canonical expression of the activating transcription factor 4 (ATF4). Conclusion:The eye is uniquely exposed to ISR responsive stressors due to its environmental exposure and relative isolation from the circulatory system which are necessary for its function. We will discuss how this pathway is critical for the proper function of the tissue, its role in development, as well as how targeting of the pathway could alleviate key aspects of diverse ophthalmic diseases.
Collapse
Affiliation(s)
- Hsiao-Sang Chu
- Wilmer Eye Institute, Department of Ophthalmology, Johns Hopkins University, Baltimore, MD, USA.,Department of Ophthalmology, National Taiwan University Hospital, College of Medicine, National Taiwan University, Taipei City, Taiwan.,Graduate Institute of Clinical Medicine, College of Medicine, National Taiwan University, Taipei City, Taiwan
| | - Cornelia Peterson
- Department of Molecular & Comparative Pathobiology, Johns Hopkins University, Baltimore, MD, USA
| | - Albert Jun
- Wilmer Eye Institute, Department of Ophthalmology, Johns Hopkins University, Baltimore, MD, USA
| | - James Foster
- Wilmer Eye Institute, Department of Ophthalmology, Johns Hopkins University, Baltimore, MD, USA
| |
Collapse
|
12
|
Robinson CM, Talty A, Logue SE, Mnich K, Gorman AM, Samali A. An Emerging Role for the Unfolded Protein Response in Pancreatic Cancer. Cancers (Basel) 2021; 13:cancers13020261. [PMID: 33445669 PMCID: PMC7828145 DOI: 10.3390/cancers13020261] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 01/04/2021] [Accepted: 01/06/2021] [Indexed: 12/17/2022] Open
Abstract
Pancreatic ductal adenocarcinoma (PDAC) is the most common form of pancreatic cancer and one of the leading causes of cancer-associated deaths in the world. It is characterised by dismal response rates to conventional therapies. A major challenge in treatment strategies for PDAC is the presence of a dense stroma that surrounds the tumour cells, shielding them from treatment. This unique tumour microenvironment is fuelled by paracrine signalling between pancreatic cancer cells and supporting stromal cell types including the pancreatic stellate cells (PSC). While our molecular understanding of PDAC is improving, there remains a vital need to develop effective, targeted treatments. The unfolded protein response (UPR) is an elaborate signalling network that governs the cellular response to perturbed protein homeostasis in the endoplasmic reticulum (ER) lumen. There is growing evidence that the UPR is constitutively active in PDAC and may contribute to the disease progression and the acquisition of resistance to therapy. Given the importance of the tumour microenvironment and cytokine signalling in PDAC, and an emerging role for the UPR in shaping the tumour microenvironment and in the regulation of cytokines in other cancer types, this review explores the importance of the UPR in PDAC biology and its potential as a therapeutic target in this disease.
Collapse
Affiliation(s)
- Claire M. Robinson
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, H91 W2TY Galway, Ireland; (C.M.R.); (A.T.); (K.M.); (A.M.G.)
| | - Aaron Talty
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, H91 W2TY Galway, Ireland; (C.M.R.); (A.T.); (K.M.); (A.M.G.)
| | - Susan E. Logue
- Department of Human Anatomy and Cell Science, Rady Faculty of Health Sciences, Max Rady College of Medicine, University of Manitoba, Winnipeg, MB R3E 0J9, Canada;
- Research Institute in Oncology and Hematology, Cancer Care Manitoba, Winnipeg, MB R3E 0V9, Canada
| | - Katarzyna Mnich
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, H91 W2TY Galway, Ireland; (C.M.R.); (A.T.); (K.M.); (A.M.G.)
| | - Adrienne M. Gorman
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, H91 W2TY Galway, Ireland; (C.M.R.); (A.T.); (K.M.); (A.M.G.)
| | - Afshin Samali
- Apoptosis Research Centre, School of Natural Sciences, National University of Ireland, H91 W2TY Galway, Ireland; (C.M.R.); (A.T.); (K.M.); (A.M.G.)
- Correspondence:
| |
Collapse
|
13
|
Eugene SP, Reddy VS, Trinath J. Endoplasmic Reticulum Stress and Intestinal Inflammation: A Perilous Union. Front Immunol 2020; 11:543022. [PMID: 33324392 PMCID: PMC7723926 DOI: 10.3389/fimmu.2020.543022] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 10/28/2020] [Indexed: 12/11/2022] Open
Abstract
The intestinal tract encompasses the largest mucosal surface fortified with a fine layer of intestinal epithelial cells along with highly sophisticated network of the lamina propria immune cells that are indispensable to sustain gut homeostasis. However, it can be challenging to uphold homeostasis when these cells in the intestine are perpetually exposed to insults of both endogenous and exogenous origin. The complex networking and dynamic microenvironment in the intestine demand highly functional cells ultimately burdening the endoplasmic reticulum (ER) leading to ER stress. Unresolved ER stress is one of the primary contributors to the pathogenesis of inflammatory bowel diseases (IBD). Studies also suggest that ER stress can be the primary cause of inflammation and/or the consequence of inflammation. Therefore, understanding the patterns of expression of ER stress regulators and deciphering the intricate interplay between ER stress and inflammatory pathways in intestinal epithelial cells in association with lamina propria immune cells contribute toward the development of novel therapies to tackle IBD. This review provides imperative insights into the molecular markers involved in the pathogenesis of IBD by potentiating ER stress and inflammation and briefly describes the potential pharmacological intervention strategies to mitigate ER stress and IBD. In addition, genetic mutations in the biomarkers contributing to abnormalities in the ER stress signaling pathways further emphasizes the relevance of biomarkers in potential treatment for IBD.
Collapse
Affiliation(s)
- Sanchez Preethi Eugene
- Department of Biological Sciences, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Hyderabad, India
| | | | - Jamma Trinath
- Department of Biological Sciences, Birla Institute of Technology and Science-Pilani, Hyderabad Campus, Hyderabad, India
| |
Collapse
|
14
|
McLaughlin M, Pedersen M, Roulstone V, Bergerhoff KF, Smith HG, Whittock H, Kyula JN, Dillon MT, Pandha HS, Vile R, Melcher AA, Harrington KJ. The PERK Inhibitor GSK2606414 Enhances Reovirus Infection in Head and Neck Squamous Cell Carcinoma via an ATF4-Dependent Mechanism. Mol Ther Oncolytics 2020; 16:238-249. [PMID: 32128359 PMCID: PMC7047134 DOI: 10.1016/j.omto.2020.01.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Accepted: 01/02/2020] [Indexed: 12/25/2022] Open
Abstract
Reovirus type 3 Dearing (reovirus) is a tumor-selective oncolytic virus currently under evaluation in clinical trials. Here, we report that the therapeutic efficacy of reovirus in head and neck squamous cell cancer can be enhanced by targeting the unfolded protein response (UPR) kinase, protein kinase R (PKR)-like endoplasmic reticulum kinase (PERK). PERK inhibition by GSK2606414 increased reovirus efficacy in both 2D and 3D models in vitro, while perturbing the normal host cell response to reovirus-induced endoplasmic reticulum (ER) stress. UPR reporter constructs were used for live-cell 3D spheroid imaging. Profiling of eIF2a-ATF4, IRE1a-XBP1, and ATF6 pathway activity revealed a context-dependent increase in eIF2a-ATF4 signaling due to GSK2606414. GSK2606414 blocked eIF2a-ATF4 signaling because of the canonical ER stress agent thapsigargin. In the context of reovirus infection, GSK2606414 induced eIF2a-ATF4 signaling. Knockdown of eIF2a kinases PERK, GCN2, and PKR revealed eIF2a-ATF4 reporter activity was dependent on either PERK or GCN2. Knockdown of ATF4 abrogated the GSK2606414-induced increase in reovirus protein levels, confirming eIF2a-ATF signaling as key to the observed phenotype. Our work identifies a novel approach to enhance the efficacy and replication of reovirus in a therapeutic setting.
Collapse
|
15
|
Jaud M, Philippe C, Di Bella D, Tang W, Pyronnet S, Laurell H, Mazzolini L, Rouault-Pierre K, Touriol C. Translational Regulations in Response to Endoplasmic Reticulum Stress in Cancers. Cells 2020; 9:cells9030540. [PMID: 32111004 PMCID: PMC7140484 DOI: 10.3390/cells9030540] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/18/2020] [Accepted: 02/24/2020] [Indexed: 12/20/2022] Open
Abstract
During carcinogenesis, almost all the biological processes are modified in one way or another. Among these biological processes affected, anomalies in protein synthesis are common in cancers. Indeed, cancer cells are subjected to a wide range of stresses, which include physical injuries, hypoxia, nutrient starvation, as well as mitotic, oxidative or genotoxic stresses. All of these stresses will cause the accumulation of unfolded proteins in the Endoplasmic Reticulum (ER), which is a major organelle that is involved in protein synthesis, preservation of cellular homeostasis, and adaptation to unfavourable environment. The accumulation of unfolded proteins in the endoplasmic reticulum causes stress triggering an unfolded protein response in order to promote cell survival or to induce apoptosis in case of chronic stress. Transcription and also translational reprogramming are tightly controlled during the unfolded protein response to ensure selective gene expression. The majority of stresses, including ER stress, induce firstly a decrease in global protein synthesis accompanied by the induction of alternative mechanisms for initiating the translation of mRNA, later followed by a translational recovery. After a presentation of ER stress and the UPR response, we will briefly present the different modes of translation initiation, then address the specific translational regulatory mechanisms acting during reticulum stress in cancers and highlight the importance of translational control by ER stress in tumours.
Collapse
Affiliation(s)
- Manon Jaud
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), F-31037 Toulouse, France; (M.J.); (S.P.); (L.M.)
- Université Toulouse III Paul-Sabatier, F-31000 Toulouse, France;
| | - Céline Philippe
- Barts Cancer Institute, Queen Mary University of London, London E1 4NS, UK; (C.P.); (D.D.B.); (W.T.); (K.R.-P.)
| | - Doriana Di Bella
- Barts Cancer Institute, Queen Mary University of London, London E1 4NS, UK; (C.P.); (D.D.B.); (W.T.); (K.R.-P.)
| | - Weiwei Tang
- Barts Cancer Institute, Queen Mary University of London, London E1 4NS, UK; (C.P.); (D.D.B.); (W.T.); (K.R.-P.)
| | - Stéphane Pyronnet
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), F-31037 Toulouse, France; (M.J.); (S.P.); (L.M.)
- Université Toulouse III Paul-Sabatier, F-31000 Toulouse, France;
| | - Henrik Laurell
- Université Toulouse III Paul-Sabatier, F-31000 Toulouse, France;
- Inserm UMR1048, I2MC (Institut des Maladies Métaboliques et Cardiovasculaires), BP 84225, CEDEX 04, 31 432 Toulouse, France
| | - Laurent Mazzolini
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), F-31037 Toulouse, France; (M.J.); (S.P.); (L.M.)
- CNRS ERL5294, CRCT, F-31037 Toulouse, France
| | - Kevin Rouault-Pierre
- Barts Cancer Institute, Queen Mary University of London, London E1 4NS, UK; (C.P.); (D.D.B.); (W.T.); (K.R.-P.)
| | - Christian Touriol
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), F-31037 Toulouse, France; (M.J.); (S.P.); (L.M.)
- Université Toulouse III Paul-Sabatier, F-31000 Toulouse, France;
- Correspondence:
| |
Collapse
|
16
|
Lacerda R, Menezes J, Candeias MM. Alternative Mechanisms of mRNA Translation Initiation in Cellular Stress Response and Cancer. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1157:117-132. [PMID: 31342440 DOI: 10.1007/978-3-030-19966-1_6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Throughout evolution, eukaryotic cells have devised different mechanisms to cope with stressful environments. When eukaryotic cells are exposed to stress stimuli, they activate adaptive pathways that allow them to restore cellular homeostasis. Most types of stress stimuli have been reported to induce a decrease in overall protein synthesis accompanied by induction of alternative mechanisms of mRNA translation initiation. Here, we present well-studied and recent examples of such stress responses and the alternative translation initiation mechanisms they induce, and discuss the consequences of such regulation for cell homeostasis and oncogenic transformation.
Collapse
Affiliation(s)
- Rafaela Lacerda
- Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, Lisboa, Portugal.,Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, University of Lisbon, Lisboa, Portugal
| | - Juliane Menezes
- Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, Lisboa, Portugal.,Faculty of Sciences, BioISI - Biosystems & Integrative Sciences Institute, University of Lisbon, Lisboa, Portugal
| | - Marco M Candeias
- Department of Human Genetics, National Institute of Health Doutor Ricardo Jorge, Lisboa, Portugal. .,MaRCU - Molecular and RNA Cancer Unit, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| |
Collapse
|
17
|
Gather F, Schmitz K, Koch K, Vogt LM, Pautz A, Kleinert H. Regulation of human inducible nitric oxide synthase expression by an upstream open reading frame. Nitric Oxide 2019; 88:50-60. [PMID: 31004763 DOI: 10.1016/j.niox.2019.04.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/04/2019] [Accepted: 04/15/2019] [Indexed: 01/05/2023]
Abstract
The human inducible nitric oxide synthase (iNOS) gene contains an upstream open reading frame (uORF) in its 5'-untranslated region (5'-UTR) implying a translational regulation of iNOS expression. Transfection experiments in human DLD-1 cells revealed that the uORF although translatable seems not to inhibit the translation start at the bona fide ATG. Our data clearly show that human iNOS translation is cap-dependent and that the 5'-UTR of the iNOS mRNA contains no internal ribosome entry site. Translation of the bona fide coding sequence is most likely mediated by a leaky scanning mechanism. The 5'-UTR is encoded by exon 1 and exon 2 of the iNOS gene with the uORF stop codon located in front of the first intron indicating an involvement of the nonsense mediated RNA decay (NMD) in iNOS regulation. SiRNA-mediated down-regulation of Upf1 resulted in enhanced endogenous cytokine iNOS expression in human DLD-1 cells. Transfection of constructs containing iNOS exon 1, intron 1 and exon 2 in front of a luciferase gene showed a clear effect of the mutation of the uORF-ATG on luciferase reportergene expression. Our data indicate that the uORF in the 5'-UTR sequence of human iNOS gene reduces its expression via the NMD mechanism.
Collapse
Affiliation(s)
- Fabian Gather
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany
| | - Katja Schmitz
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany
| | - Kathrin Koch
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany
| | - Lea-Marie Vogt
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany
| | - Andrea Pautz
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany.
| | - Hartmut Kleinert
- Department of Pharmacology, University Medical Center of the Johannes Gutenberg University Mainz, Obere Zahlbacher Str. 67, 55101, Mainz, Germany.
| |
Collapse
|
18
|
Jaud M, Philippe C, Van Den Berghe L, Ségura C, Mazzolini L, Pyronnet S, Laurell H, Touriol C. The PERK Branch of the Unfolded Protein Response Promotes DLL4 Expression by Activating an Alternative Translation Mechanism. Cancers (Basel) 2019; 11:cancers11020142. [PMID: 30691003 PMCID: PMC6406545 DOI: 10.3390/cancers11020142] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 01/15/2019] [Accepted: 01/22/2019] [Indexed: 12/23/2022] Open
Abstract
Delta-like 4 (DLL4) is a pivotal endothelium specific Notch ligand that has been shown to function as a regulating factor during physiological and pathological angiogenesis. DLL4 functions as a negative regulator of angiogenic branching and sprouting. Interestingly, Dll4 is with Vegf-a one of the few examples of haplo-insufficiency, resulting in obvious vascular abnormalities and in embryonic lethality. These striking phenotypes are a proof of concept of the crucial role played by the bioavailability of VEGF and DLL4 during vessel patterning and that there must be a very fine-tuning of DLL4 expression level. However, to date the expression regulation of this factor was poorly studied. In this study, we showed that the DLL4 5′-UTR harbors an Internal Ribosomal Entry Site (IRES) that, in contrast to cap-dependent translation, was efficiently utilized in cells subjected to several stresses including hypoxia and endoplasmic reticulum stress (ER stress). We identified PERK, a kinase activated by ER stress, as the driver of DLL4 IRES-mediated translation, and hnRNP-A1 as an IRES-Trans-Acting Factor (ITAF) participating in the IRES-dependent translation of DLL4 during endoplasmic reticulum stress. The presence of a stress responsive internal ribosome entry site in the DLL4 msRNA suggests that the process of alternative translation initiation, by controlling the expression of this factor, could have a crucial role in the control of endothelial tip cell function.
Collapse
Affiliation(s)
- Manon Jaud
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
| | - Céline Philippe
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
| | - Loic Van Den Berghe
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
- Vectorology Plateform, Technological pole CRCT, F-31037 Toulouse, France.
| | - Christèle Ségura
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
- Vectorology Plateform, Technological pole CRCT, F-31037 Toulouse, France.
| | - Laurent Mazzolini
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
| | - Stéphane Pyronnet
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
| | - Henrik Laurell
- Inserm UMR1048, I2MC (Institut des Maladies Métaboliques et Cardiovasculaires), Toulouse, France.
| | - Christian Touriol
- Inserm UMR1037, CRCT (Cancer Research Center of Toulouse), CNRS ERL5294, Université Toulouse III Paul-Sabatier, F-31037 Toulouse, France.
| |
Collapse
|
19
|
Ross JA, Bressler KR, Thakor N. Eukaryotic Initiation Factor 5B (eIF5B) Cooperates with eIF1A and eIF5 to Facilitate uORF2-Mediated Repression of ATF4 Translation. Int J Mol Sci 2018; 19:E4032. [PMID: 30551605 PMCID: PMC6321046 DOI: 10.3390/ijms19124032] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2018] [Revised: 12/08/2018] [Accepted: 12/10/2018] [Indexed: 12/20/2022] Open
Abstract
A variety of cellular stresses lead to global translation attenuation due to phosphorylation of the alpha subunit of eukaryotic initiation factor 2 (eIF2), which decreases the availability of the eIF2-GTP-Met-tRNAi ternary complex. However, a subset of mRNAs continues to be translated by non-canonical mechanisms under these conditions. In fact, although translation initiation of activating transcription factor 4 (ATF4) is normally repressed by an upstream open reading frame (uORF), a decreased availability of ternary complex leads to increased translation of the main ATF4-coding ORF. We show here that siRNA-mediated depletion of eIF5B-which can substitute for eIF2 in delivering Met-tRNAi-leads to increased levels of ATF4 protein in mammalian cells. This de-repression is not due to phosphorylation of eIF2α under conditions of eIF5B depletion. Although eIF5B depletion leads to a modest increase in the steady-state levels of ATF4 mRNA, we show by polysome profiling that the depletion of eIF5B enhances ATF4 expression primarily at the level of translation. Moreover, eIF5B silencing increases the expression of an ATF4-luciferase translational reporter by a mechanism requiring the repressive uORF2. Further experiments suggest that eIF5B cooperates with eIF1A and eIF5, but not eIF2A, to facilitate the uORF2-mediated repression of ATF4 translation.
Collapse
Affiliation(s)
- Joseph A Ross
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive W, Lethbridge, AB T1K 3M4, Canada.
| | - Kamiko R Bressler
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive W, Lethbridge, AB T1K 3M4, Canada.
| | - Nehal Thakor
- Department of Chemistry and Biochemistry, University of Lethbridge, 4401 University Drive W, Lethbridge, AB T1K 3M4, Canada.
- Canadian Centre for Behavioral Neuroscience (CCBN), Department of Neuroscience, University of Lethbridge, 4401 University Drive W, Lethbridge, AB T1K 3M4, Canada.
- Arnie Charbonneau Cancer Institute, Cumming School of Medicine, University of Calgary, 3280 Hospital Drive NW, Calgary, AB T2N 4Z6, Canada.
| |
Collapse
|
20
|
Logan SM, Wu CW, Storey KB. The squirrel with the lagging eIF2: Global suppression of protein synthesis during torpor. Comp Biochem Physiol A Mol Integr Physiol 2018; 227:161-171. [PMID: 30343059 DOI: 10.1016/j.cbpa.2018.10.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Accepted: 10/14/2018] [Indexed: 11/17/2022]
Abstract
Hibernating mammals use strong metabolic rate depression and a reduction in body temperature to near-ambient to survive the cold winter months. During torpor, protein synthesis is suppressed but can resume during interbout arousals. The current study aimed to identify molecular targets responsible for the global suppression of protein synthesis during torpor as well as possible mechanisms that could allow for selective protein translation to continue over this time. Relative changes in protein expression and/or phosphorylation levels of key translation factors (ribosomal protein S6, eIF4E, eIF2α, eEF2) and their upstream regulators (mTOR, TSC2, p70 S6K, 4EBP) were analyzed in liver and kidney of 13-lined ground squirrels (Ictidomys tridecemlineatus) sampled from six points over the torpor-arousal cycle. The results indicate that both organs reduce protein synthesis during torpor by decreasing mTOR and TSC2 phosphorylation between 30 and 70% of control levels. Translation resumes during interbout arousal when p-p70 S6K, p-rpS6, and p-4EBP levels returned to control values or above. Only liver translation factors were activated or disinhibited during periods of torpor itself, with >3-fold increases in total eIF2α and eEF2 protein levels, and a decrease in p-eEF2 (T56) to as low as 16% of the euthermic control value. These data shed light on a possible molecular mechanism involving eIF2α that could enable the translation of key transcripts during times of cell stress.
Collapse
Affiliation(s)
- Samantha M Logan
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Cheng-Wei Wu
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada
| | - Kenneth B Storey
- Department of Biology, Carleton University, 1125 Colonel By Drive, Ottawa, Ontario K1S 5B6, Canada.
| |
Collapse
|
21
|
Beyond quality control: The role of nonsense-mediated mRNA decay (NMD) in regulating gene expression. Semin Cell Dev Biol 2018; 75:78-87. [DOI: 10.1016/j.semcdb.2017.08.053] [Citation(s) in RCA: 93] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 08/25/2017] [Accepted: 08/28/2017] [Indexed: 11/23/2022]
|
22
|
Täger J, Kohl S, Birch DG, Wheaton DKH, Wissinger B, Reuter P. An early nonsense mutation facilitates the expression of a short isoform of CNGA3 by alternative translation initiation. Exp Eye Res 2018; 171:48-53. [PMID: 29499183 DOI: 10.1016/j.exer.2018.02.027] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2017] [Revised: 02/26/2018] [Accepted: 02/26/2018] [Indexed: 11/24/2022]
Abstract
The cyclic nucleotide-gated (CNG) channel - composed of CNGA3 and CNGB3 subunits - mediates the influx of cations in cone photoreceptors after light stimulation and thus is a key element in cone phototransduction. Mutations in CNGA3 and CNGB3 are associated with achromatopsia, a rare autosomal recessive retinal disorder. Here, we demonstrate that the presence of an early nonsense mutation in CNGA3 induces the usage of a downstream alternative translation initiation site giving rise to a short CNGA3 isoform. The expression of this short isoform was verified by Western blot analysis and DAB staining of HEK293 cells and cone photoreceptor-like 661W cells expressing CNGA3-GST fusion constructs. Functionality of the short isoform was confirmed by a cellular calcium influx assay. Furthermore, patients carrying an early nonsense mutation were analyzed for residual cone photoreceptor function in order to identify a potential role of the short isoform to modify the clinical outcome in achromatopsia patients. Yet the results suggest that the short isoform is not able to compensate for the loss of the long isoform leaving the biological role of this variant unclear.
Collapse
Affiliation(s)
- Joachim Täger
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany; Graduate School of Cellular and Molecular Neuroscience, University of Tübingen, Tübingen, Germany
| | - Susanne Kohl
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany
| | | | | | - Bernd Wissinger
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
| | - Peggy Reuter
- Molecular Genetics Laboratory, Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.
| |
Collapse
|
23
|
Cheng W, Wang S, Mestre AA, Fu C, Makarem A, Xian F, Hayes LR, Lopez-Gonzalez R, Drenner K, Jiang J, Cleveland DW, Sun S. C9ORF72 GGGGCC repeat-associated non-AUG translation is upregulated by stress through eIF2α phosphorylation. Nat Commun 2018; 9:51. [PMID: 29302060 PMCID: PMC5754368 DOI: 10.1038/s41467-017-02495-z] [Citation(s) in RCA: 134] [Impact Index Per Article: 22.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 12/01/2017] [Indexed: 01/04/2023] Open
Abstract
Hexanucleotide repeat expansion in C9ORF72 is the most frequent cause of both amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). Here we demonstrate that the repeat-associated non-AUG (RAN) translation of (GGGGCC) n -containing RNAs into poly-dipeptides can initiate in vivo without a 5'-cap. The primary RNA substrate for RAN translation of C9ORF72 sense repeats is shown to be the spliced first intron, following its excision from the initial pre-mRNA and transport to the cytoplasm. Cap-independent RAN translation is shown to be upregulated by various stress stimuli through phosphorylation of the α subunit of eukaryotic initiation factor-2 (eIF2α), the core event of an integrated stress response (ISR). Compounds inhibiting phospho-eIF2α-signaling pathways are shown to suppress RAN translation. Since the poly-dipeptides can themselves induce stress, these findings support a feedforward loop with initial repeat-mediated toxicity enhancing RAN translation and subsequent production of additional poly-dipeptides through ISR, thereby promoting progressive disease.
Collapse
Affiliation(s)
- Weiwei Cheng
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Shaopeng Wang
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Alexander A Mestre
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Chenglai Fu
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Andres Makarem
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Fengfan Xian
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Lindsey R Hayes
- Brain Science Institute and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA
| | - Rodrigo Lopez-Gonzalez
- Department of Neurology, University of Massachusetts Medical School, Worcester, MA, 01605, USA
| | - Kevin Drenner
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Jie Jiang
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Don W Cleveland
- Ludwig Institute for Cancer Research and Department of Cellular and Molecular Medicine, University of California at San Diego, La Jolla, CA, 92093, USA
| | - Shuying Sun
- Department of Pathology and Brain Science Institute, Johns Hopkins University School of Medicine, Baltimore, MD, 21205, USA.
| |
Collapse
|
24
|
Pitale PM, Gorbatyuk O, Gorbatyuk M. Neurodegeneration: Keeping ATF4 on a Tight Leash. Front Cell Neurosci 2017; 11:410. [PMID: 29326555 PMCID: PMC5736573 DOI: 10.3389/fncel.2017.00410] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/05/2017] [Indexed: 12/15/2022] Open
Abstract
Activation of the endoplasmic reticulum (ER) stress and ER stress response, also known as the unfolded protein response (UPR), is common to various degenerative disorders. Therefore, signaling components of the UPR are currently emerging as potential targets for intervention and treatment of human diseases. One UPR signaling member, activating transcription factor 4 (ATF4), has been found up-regulated in many pathological conditions, pointing to therapeutic potential in targeting its expression. In cells, ATF4 governs multiple signaling pathways, including autophagy, oxidative stress, inflammation, and translation, suggesting a multifaceted role of ATF4 in the progression of various pathologies. However, ATF4 has been shown to trigger both pro-survival and pro-death pathways, and this, perhaps, can explain the contradictory opinions in current literature regarding targeting ATF4 for clinical application. In this review, we summarized recent published studies from our labs and others that focus on the therapeutic potential of the strategy controlling ATF4 expression in different retinal and neurodegenerative disorders.
Collapse
Affiliation(s)
- Priyamvada M Pitale
- Department of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Oleg Gorbatyuk
- Department of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, United States.,Department of Neurology, Center for Neurodegeneration and Experimental Therapeutics, University of Alabama at Birmingham, Birmingham, AL, United States
| | - Marina Gorbatyuk
- Department of Optometry and Vision Science, School of Optometry, University of Alabama at Birmingham, Birmingham, AL, United States
| |
Collapse
|
25
|
Marques-Ramos A, Candeias MM, Menezes J, Lacerda R, Willcocks M, Teixeira A, Locker N, Romão L. Cap-independent translation ensures mTOR expression and function upon protein synthesis inhibition. RNA (NEW YORK, N.Y.) 2017; 23:1712-1728. [PMID: 28821580 PMCID: PMC5648038 DOI: 10.1261/rna.063040.117] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Accepted: 08/15/2017] [Indexed: 06/07/2023]
Abstract
The mechanistic/mammalian target of rapamycin (mTOR) is a conserved serine/threonine kinase that integrates cellular signals from the nutrient and energy status to act, namely, on the protein synthesis machinery. While major advances have emerged regarding the regulators and effects of the mTOR signaling pathway, little is known about the regulation of mTOR gene expression. Here, we show that the human mTOR transcript can be translated in a cap-independent manner, and that its 5' untranslated region (UTR) is a highly folded RNA scaffold capable of binding directly to the 40S ribosomal subunit. We further demonstrate that mTOR is able to bypass the cap requirement for translation both in normal and hypoxic conditions. Moreover, our data reveal that the cap-independent translation of mTOR is necessary for its ability to induce cell-cycle progression into S phase. These results suggest a novel regulatory mechanism for mTOR gene expression that integrates the global protein synthesis changes induced by translational inhibitory conditions.
Collapse
Affiliation(s)
- Ana Marques-Ramos
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Marco M Candeias
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- Laboratory of Bioimaging and Cell Signaling, Graduate School of Biostudies, Kyoto University, Kyoto 606-8501, Japan
| | - Juliane Menezes
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Rafaela Lacerda
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| | - Margaret Willcocks
- Microbial and Cellular Sciences Department, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7TE, United Kingdom
| | - Alexandre Teixeira
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
| | - Nicolas Locker
- Microbial and Cellular Sciences Department, Faculty of Health and Medical Sciences, University of Surrey, Guildford GU2 7TE, United Kingdom
| | - Luísa Romão
- Departamento de Genética Humana, Instituto Nacional de Saúde Doutor Ricardo Jorge, 1649-016 Lisboa, Portugal
- Biosystems and Integrative Sciences Institute (BioISI), Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal
| |
Collapse
|
26
|
Alonge KM, Meares GP, Hillgartner FB. Glucagon and Insulin Cooperatively Stimulate Fibroblast Growth Factor 21 Gene Transcription by Increasing the Expression of Activating Transcription Factor 4. J Biol Chem 2017; 292:5239-5252. [PMID: 28188284 DOI: 10.1074/jbc.m116.762922] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2016] [Revised: 02/02/2017] [Indexed: 01/07/2023] Open
Abstract
Previous studies have shown that glucagon cooperatively interacts with insulin to stimulate hepatic FGF21 gene expression. Here we investigated the mechanism by which glucagon and insulin increased FGF21 gene transcription in primary hepatocyte cultures. Transfection analyses demonstrated that glucagon plus insulin induction of FGF21 transcription was conferred by two activating transcription factor 4 (ATF4) binding sites in the FGF21 gene. Glucagon plus insulin stimulated a 5-fold increase in ATF4 protein abundance, and knockdown of ATF4 expression suppressed the ability of glucagon plus insulin to increase FGF21 expression. In hepatocytes incubated in the presence of insulin, treatment with a PKA-selective agonist mimicked the ability of glucagon to stimulate ATF4 and FGF21 expression. Inhibition of PKA, PI3K, Akt, and mammalian target of rapamycin complex 1 (mTORC1) suppressed the ability of glucagon plus insulin to stimulate ATF4 and FGF21 expression. Additional analyses demonstrated that chenodeoxycholic acid (CDCA) induced a 6-fold increase in ATF4 expression and that knockdown of ATF4 expression suppressed the ability of CDCA to increase FGF21 gene expression. CDCA increased the phosphorylation of eIF2α, and inhibition of eIF2α signaling activity suppressed CDCA regulation of ATF4 and FGF21 expression. These results demonstrate that glucagon plus insulin increases FGF21 transcription by stimulating ATF4 expression and that activation of cAMP/PKA and PI3K/Akt/mTORC1 mediates the effect of glucagon plus insulin on ATF4 expression. These results also demonstrate that CDCA regulation of FGF21 transcription is mediated at least partially by an eIF2α-dependent increase in ATF4 expression.
Collapse
Affiliation(s)
| | - Gordon P Meares
- Microbiology, Immunology, and Cell Biology, West Virginia University, Morgantown, West Virginia 26506
| | | |
Collapse
|
27
|
Role of Eukaryotic Initiation Factors during Cellular Stress and Cancer Progression. J Nucleic Acids 2016; 2016:8235121. [PMID: 28083147 PMCID: PMC5204094 DOI: 10.1155/2016/8235121] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Accepted: 11/14/2016] [Indexed: 12/12/2022] Open
Abstract
Protein synthesis can be segmented into distinct phases comprising mRNA translation initiation, elongation, and termination. Translation initiation is a highly regulated and rate-limiting step of protein synthesis that requires more than 12 eukaryotic initiation factors (eIFs). Extensive evidence shows that the transcriptome and corresponding proteome do not invariably correlate with each other in a variety of contexts. In particular, translation of mRNAs specific to angiogenesis, tumor development, and apoptosis is altered during physiological and pathophysiological stress conditions. In cancer cells, the expression and functions of eIFs are hampered, resulting in the inhibition of global translation and enhancement of translation of subsets of mRNAs by alternative mechanisms. A precise understanding of mechanisms involving eukaryotic initiation factors leading to differential protein expression can help us to design better strategies to diagnose and treat cancer. The high spatial and temporal resolution of translation control can have an immediate effect on the microenvironment of the cell in comparison with changes in transcription. The dysregulation of mRNA translation mechanisms is increasingly being exploited as a target to treat cancer. In this review, we will focus on this context by describing both canonical and noncanonical roles of eIFs, which alter mRNA translation.
Collapse
|
28
|
Li Q, Gao WQ, Dai WY, Yu C, Zhu RY, Jin J. ATF2 translation is induced under chemotherapeutic drug-mediated cellular stress via an IRES-dependent mechanism in human hepatic cancer Bel7402 cells. Oncol Lett 2016; 12:4795-4802. [PMID: 28105187 DOI: 10.3892/ol.2016.5274] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 08/09/2016] [Indexed: 12/16/2022] Open
Abstract
Activating transcription factor (ATF) 2 is a member of the ATF/cyclic AMP-responsive element binding protein family, which exhibits both oncogenic and tumor-suppressor functions. In our preliminary experiments, it was observed that the expression of the ATF2 protein was induced following treatment with adriamycin (ADR) and paclitaxel (PTX), which may be regulated by internal ribosome entry segment (IRES)-mediated translation. By constructing a bicistronic vector containing the ATF2 5'-untranslated region (UTR), it was demonstrated that the ATF2 5'-UTR contains an IRES and maps a 30-nucleotide (nt) sequence (from nt 299 to nt ~269), which was essential for the IRES activity. The ATF2 IRES activity exhibited significant variation in different cell lines. In addition, it was observed that ADR and PTX also induced ATF2 IRES activity in Bel7402 cells. The present study has demonstrated that ATF2 translation is initiated via IRES, which is upregulated by ADR and PTX, thus suggesting that the regulation of the IRES-dependent translation of ATF2 may be involved in effecting the cancer cell response to chemotherapeutic drugs-mediated cellular stress.
Collapse
Affiliation(s)
- Qi Li
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Wen-Qing Gao
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Wen-Yan Dai
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Chuang Yu
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Rui-Yu Zhu
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| | - Jian Jin
- Laboratory of Molecular Pharmacology, School of Pharmaceutical Sciences, Jiangnan University, Wuxi, Jiangsu 214122, P.R. China
| |
Collapse
|
29
|
Pakos-Zebrucka K, Koryga I, Mnich K, Ljujic M, Samali A, Gorman AM. The integrated stress response. EMBO Rep 2016; 17:1374-1395. [PMID: 27629041 DOI: 10.15252/embr.201642195] [Citation(s) in RCA: 1452] [Impact Index Per Article: 181.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2016] [Accepted: 08/23/2016] [Indexed: 02/06/2023] Open
Abstract
In response to diverse stress stimuli, eukaryotic cells activate a common adaptive pathway, termed the integrated stress response (ISR), to restore cellular homeostasis. The core event in this pathway is the phosphorylation of eukaryotic translation initiation factor 2 alpha (eIF2α) by one of four members of the eIF2α kinase family, which leads to a decrease in global protein synthesis and the induction of selected genes, including the transcription factor ATF4, that together promote cellular recovery. The gene expression program activated by the ISR optimizes the cellular response to stress and is dependent on the cellular context, as well as on the nature and intensity of the stress stimuli. Although the ISR is primarily a pro-survival, homeostatic program, exposure to severe stress can drive signaling toward cell death. Here, we review current understanding of the ISR signaling and how it regulates cell fate under diverse types of stress.
Collapse
Affiliation(s)
- Karolina Pakos-Zebrucka
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Izabela Koryga
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Katarzyna Mnich
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Mila Ljujic
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Afshin Samali
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| | - Adrienne M Gorman
- Apoptosis Research Centre, National University of Ireland Galway, Galway, Ireland School of Natural Sciences, National University of Ireland Galway, Galway, Ireland
| |
Collapse
|
30
|
mTORC1 and CK2 coordinate ternary and eIF4F complex assembly. Nat Commun 2016; 7:11127. [PMID: 27040916 PMCID: PMC4822005 DOI: 10.1038/ncomms11127] [Citation(s) in RCA: 65] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2015] [Accepted: 02/23/2016] [Indexed: 02/02/2023] Open
Abstract
Ternary complex (TC) and eIF4F complex assembly are the two major rate-limiting steps in translation initiation regulated by eIF2α phosphorylation and the mTOR/4E-BP pathway, respectively. How TC and eIF4F assembly are coordinated, however, remains largely unknown. We show that mTOR suppresses translation of mRNAs activated under short-term stress wherein TC recycling is attenuated by eIF2α phosphorylation. During acute nutrient or growth factor stimulation, mTORC1 induces eIF2β phosphorylation and recruitment of NCK1 to eIF2, decreases eIF2α phosphorylation and bolsters TC recycling. Accordingly, eIF2β mediates the effect of mTORC1 on protein synthesis and proliferation. In addition, we demonstrate a formerly undocumented role for CK2 in regulation of translation initiation, whereby CK2 stimulates phosphorylation of eIF2β and simultaneously bolsters eIF4F complex assembly via the mTORC1/4E-BP pathway. These findings imply a previously unrecognized mode of translation regulation, whereby mTORC1 and CK2 coordinate TC and eIF4F complex assembly to stimulate cell proliferation. Ternary complex (TC) and eIF4F complex assembly are rate-limiting steps in translation initiation that are regulated by eIF2α phosphorylation and the mTOR/4E-BP pathway. Here the authors show that the protein kinases mTORC1 and CK2 coordinate TC and eIF4F complex assembly through eIF2β to stimulate cell proliferation.
Collapse
|
31
|
Lahlali T, Plissonnier ML, Romero-López C, Michelet M, Ducarouge B, Berzal-Herranz A, Zoulim F, Mehlen P, Parent R. Netrin-1 Protects Hepatocytes Against Cell Death Through Sustained Translation During the Unfolded Protein Response. Cell Mol Gastroenterol Hepatol 2016; 2:281-301.e9. [PMID: 28174720 PMCID: PMC5042567 DOI: 10.1016/j.jcmgh.2015.12.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 12/21/2015] [Indexed: 02/08/2023]
Abstract
BACKGROUND & AIMS Netrin-1, a multifunctional secreted protein, is up-regulated in cancer and inflammation. Netrin-1 blocks apoptosis induced by the prototypical dependence receptors deleted in colorectal carcinoma and uncoordinated phenotype-5. Although the unfolded protein response (UPR) triggers apoptosis on exposure to stress, it first attempts to restore endoplasmic reticulum homeostasis to foster cell survival. Importantly, UPR is implicated in chronic liver conditions including hepatic oncogenesis. Netrin-1's implication in cell survival on UPR in this context is unknown. METHODS Isolation of translational complexes, determination of RNA secondary structures by selective 2'-hydroxyl acylation and primer extension/dimethyl sulfate, bicistronic constructs, as well as conventional cell biology and biochemistry approaches were used on in vitro-grown hepatocytic cells, wild-type, and netrin-1 transgenic mice. RESULTS HepaRG cells constitute a bona fide model for UPR studies in vitro through adequate activation of the 3 sensors of the UPR (protein kinase RNA-like endoplasmic reticulum kinase (PERK)), inositol requiring enzyme 1α (IRE1α), and activated transcription factor 6 (ATF6). The netrin-1 messenger RNA 5'-end was shown to fold into a complex double pseudoknot and bear E-loop motifs, both of which are representative hallmarks of related internal ribosome entry site regions. Cap-independent translation of netrin 5' untranslated region-driven luciferase was observed on UPR in vitro. Unlike several structurally related oncogenic transcripts (l-myc, c-myc, c-myb), netrin-1 messenger RNA was selected for translation during UPR both in human hepatocytes and in mice livers. Depletion of netrin-1 during UPR induces apoptosis, leading to cell death through an uncoordinated phenotype-5A/C-mediated involvement of protein phosphatase 2A and death-associated protein kinase 1 in vitro and in netrin transgenic mice. CONCLUSIONS UPR-resistant, internal ribosome entry site-driven netrin-1 translation leads to the inhibition of uncoordinated phenotype-5/death-associated protein kinase 1-mediated apoptosis in the hepatic context during UPR, a hallmark of chronic liver disease.
Collapse
Key Words
- ATF6, activated transcription factor 6
- CMV, cytomegalovirus
- DAPK, death-associated protein kinase
- DMS, dimethyl sulfate
- DR, dependence receptor
- DTT, dithiothreitol
- ER, endoplasmic reticulum
- FLuc, Firefly luciferase
- HBV, hepatitis B virus
- HCC, hepatocellular carcinoma
- HCV, hepatitis C virus
- Hepatocyte
- IRE1α, inositol requiring enzyme 1α
- IRES, internal ribosome entry site
- LSL, (Lox-Stop-Lox)
- NMIA, N-methyl-isatoic anhydride
- Netrin
- PBS, phosphate-buffered saline
- PERK, protein kinase RNA (PKR)-like endoplasmic reticulum kinase
- PP2A, protein phosphatase 2A
- PR65β, erine/threonine-protein phosphatase 2A 65 kDa regulatory subunit A beta isoform
- RLuc, Renilla lucerifase
- TUNEL, terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling
- Translation
- Tu, tunicamycin
- UNC5, uncoordinated phenotype-5
- UPR
- UPR, unfolded protein response
- UTR, untranslated region
- VR1, vanilloid receptor 1
- eIF2α, Eukaryotic translation initiation factor 2A
- mRNA, messenger RNA
- pBic, Bicistronic plasmid
- qRT-PCR, quantitative reverse-transcription polymerase chain reaction
- siRNA, small interfering RNA
Collapse
Affiliation(s)
- Thomas Lahlali
- Inserm U1052-UMR CNRS 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Marie-Laure Plissonnier
- Inserm U1052-UMR CNRS 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Cristina Romero-López
- Instituto de Parasitología y Biomedicina López-Neyra Consejo Superior de Investigaciones Científicas, Ciencia e Investigación (IPBLN-CSIC), Parque Tecnológico Ciencias de la Salud Granada, Armilla, Granada, Spain
| | - Maud Michelet
- Inserm U1052-UMR CNRS 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Benjamin Ducarouge
- Inserm U1052-UMR Centre National de la Recherche Scientifique 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Alfredo Berzal-Herranz
- Instituto de Parasitología y Biomedicina López-Neyra Consejo Superior de Investigaciones Científicas, Ciencia e Investigación (IPBLN-CSIC), Parque Tecnológico Ciencias de la Salud Granada, Armilla, Granada, Spain
| | - Fabien Zoulim
- Inserm U1052-UMR CNRS 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Patrick Mehlen
- Inserm U1052-UMR Centre National de la Recherche Scientifique 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France
| | - Romain Parent
- Inserm U1052-UMR CNRS 5286, Centre Léon Berard, Centre de Recherche en Cancérologie, Lyon, France,Correspondence Address correspondence to: Romain Parent, PharmD, PhD, Inserm U1052, 151 Cours Albert Thomas, F-69424 Lyon Cedex 03, France. fax: (33) 4-72-68-19-71.Inserm U1052151 Cours Albert ThomasF-69424 Lyon Cedex 03France
| |
Collapse
|
32
|
Pan IC, Tsai HH, Cheng YT, Wen TN, Buckhout TJ, Schmidt W. Post-Transcriptional Coordination of the Arabidopsis Iron Deficiency Response is Partially Dependent on the E3 Ligases RING DOMAIN LIGASE1 (RGLG1) and RING DOMAIN LIGASE2 (RGLG2). Mol Cell Proteomics 2015; 14:2733-52. [PMID: 26253232 DOI: 10.1074/mcp.m115.048520] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Indexed: 11/06/2022] Open
Abstract
Acclimation to changing environmental conditions is mediated by proteins, the abundance of which is carefully tuned by an elaborate interplay of DNA-templated and post-transcriptional processes. To dissect the mechanisms that control and mediate cellular iron homeostasis, we conducted quantitative high-resolution iTRAQ proteomics and microarray-based transcriptomic profiling of iron-deficient Arabidopsis thaliana plants. A total of 13,706 and 12,124 proteins was identified with a quadrupole-Orbitrap hybrid mass spectrometer in roots and leaves, respectively. This deep proteomic coverage allowed accurate estimates of post-transcriptional regulation in response to iron deficiency. Similarly regulated transcripts were detected in only 13% (roots) and 11% (leaves) of the 886 proteins that differentially accumulated between iron-sufficient and iron-deficient plants, indicating that the majority of the iron-responsive proteins was post-transcriptionally regulated. Mutants harboring defects in the RING DOMAIN LIGASE1 (RGLG1)(1) and RING DOMAIN LIGASE2 (RGLG2) showed a pleiotropic phenotype that resembled iron-deficient plants with reduced trichome density and the formation of branched root hairs. Proteomic and transcriptomic profiling of rglg1 rglg2 double mutants revealed that the functional RGLG protein is required for the regulation of a large set of iron-responsive proteins including the coordinated expression of ribosomal proteins. This integrative analysis provides a detailed catalog of post-transcriptionally regulated proteins and allows the concept of a chiefly transcriptionally regulated iron deficiency response to be revisited. Protein data are available via ProteomeXchange with identifier PXD002126.
Collapse
Affiliation(s)
- I-Chun Pan
- From the ‡Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Huei-Hsuan Tsai
- From the ‡Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Ya-Tan Cheng
- From the ‡Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Tuan-Nan Wen
- From the ‡Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | | | - Wolfgang Schmidt
- From the ‡Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan; ¶Biotechnology Center, National Chung-Hsing University, Taichung, Taiwan; ‖Genome and Systems Biology Degree Program, College of Life Science, National Taiwan University, Taipei, Taiwan
| |
Collapse
|
33
|
Xia J, Zhang Y, Xin L, Kong S, Chen Y, Yang S, Li K. Global Transcriptomic Profiling of Cardiac Hypertrophy and Fatty Heart Induced by Long-Term High-Energy Diet in Bama Miniature Pigs. PLoS One 2015; 10:e0132420. [PMID: 26161779 PMCID: PMC4498776 DOI: 10.1371/journal.pone.0132420] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 06/13/2015] [Indexed: 12/31/2022] Open
Abstract
A long-term high-energy diet affects human health and leads to obesity and metabolic syndrome in addition to cardiac steatosis and hypertrophy. Ectopic fat accumulation in the heart has been demonstrated to be a risk factor for heart disorders, but the molecular mechanism of heart disease remains largely unknown. Bama miniature pigs were fed a high-fat, high-sucrose diet (HFHSD) for 23 months. These pigs developed symptoms of metabolic syndrome and showed cardiac steatosis and hypertrophy with a greatly increased body weight (2.73-fold, P<0.01), insulin level (4.60-fold, P<0.01), heart weight (1.82-fold, P<0.05) and heart volume (1.60-fold, P<0.05) compared with the control pigs. To understand the molecular mechanisms of cardiac steatosis and hypertrophy, nine pig heart cRNA samples were hybridized to porcine GeneChips. Microarray analyses revealed that 1,022 genes were significantly differentially expressed (P<0.05, ≥1.5-fold change), including 591 up-regulated and 431 down-regulated genes in the HFHSD group relative to the control group. KEGG analysis indicated that the observed heart disorder involved the signal transduction-related MAPK, cytokine, and PPAR signaling pathways, energy metabolism-related fatty acid and oxidative phosphorylation signaling pathways, heart function signaling-related focal adhesion, axon guidance, hypertrophic cardiomyopathy and actin cytoskeleton signaling pathways, inflammation and apoptosis pathways, and others. Quantitative RT-PCR assays identified several important differentially expressed heart-related genes, including STAT3, ACSL4, ATF4, FADD, PPP3CA, CD74, SLA-8, VCL, ACTN2 and FGFR1, which may be targets of further research. This study shows that a long-term, high-energy diet induces obesity, cardiac steatosis, and hypertrophy and provides insights into the molecular mechanisms of hypertrophy and fatty heart to facilitate further research.
Collapse
Affiliation(s)
- Jihan Xia
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, P. R. China
| | - Yuanyuan Zhang
- College of Veterinary Medicine, China Agricultural University, Beijing, P. R. China
| | - Leilei Xin
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, P. R. China
| | - Siyuan Kong
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, P. R. China
| | - Yaoxing Chen
- College of Veterinary Medicine, China Agricultural University, Beijing, P. R. China
| | - Shulin Yang
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, P. R. China
- * E-mail:
| | - Kui Li
- State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, P. R. China
- Agricultural Genomes Institute at Shenzhen, CAAS, Shenzhen, 518120, P.R. China
| |
Collapse
|
34
|
Khan I, Tang E, Arany P. Molecular pathway of near-infrared laser phototoxicity involves ATF-4 orchestrated ER stress. Sci Rep 2015; 5:10581. [PMID: 26030745 PMCID: PMC4450753 DOI: 10.1038/srep10581] [Citation(s) in RCA: 304] [Impact Index Per Article: 33.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Accepted: 04/17/2015] [Indexed: 11/24/2022] Open
Abstract
High power lasers are used extensively in medicine while lower power applications are popular for optical imaging, optogenetics, skin rejuvenation and a therapeutic modality termed photobiomodulation (PBM). This study addresses the therapeutic dose limits, biological safety and molecular pathway of near-infrared (NIR) laser phototoxicity. Increased erythema and tissue damage were noted in mice skin and cytotoxicity in cell cultures at phototoxic laser doses involving generation of reactive oxygen species (ROS) coupled with a rise in surface temperature (>45 °C). NIR laser phototoxicity results from Activating Transcription Factor-4 (ATF-4) mediated endoplasmic reticulum stress and autophagy. Neutralizations of heat or ROS and overexpressing ATF-4 were noted to rescue NIR laser phototoxicity. Further, NIR laser mediated phototoxicity was noted to be non-genotoxic and non-mutagenic. This study outlines the mechanism of NIR laser phototoxicity and the utility of monitoring surface temperature and ATF4 expression as potential biomarkers to develop safe and effective clinical applications.
Collapse
Affiliation(s)
- Imran Khan
- Cell Regulation and Control Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda MD
| | - Elieza Tang
- Cell Regulation and Control Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda MD
| | - Praveen Arany
- Cell Regulation and Control Unit, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda MD
| |
Collapse
|
35
|
Wei N, Zhu LQ, Liu D. ATF4: a Novel Potential Therapeutic Target for Alzheimer's Disease. Mol Neurobiol 2014; 52:1765-1770. [PMID: 25381575 DOI: 10.1007/s12035-014-8970-8] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 10/28/2014] [Indexed: 12/27/2022]
Abstract
Activating transcription factor 4 (ATF4) belongs to the activating transcription factor family and its expression is increased upon the stimulation of a diverse array of microenvironmental stresses. ATF4 plays a major role in the development, metabolism, and memory formation. Alzheimer's disease (AD) is a prevalent neurodegenerative disease in aged population. The dominant pathological changes in AD brain, including the neurofibrillary tangles, consist of hyperphosphorylated tau protein, senile plaques composed of β-amyloid proteins, loss of neurons in the whole brain, and dysfunction of synapses. The protein level of ATF4 is upregulated in both AD brain and AD mouse model, indicating its latent roles in the pathogenesis of this disease. In this paper, we reviewed the related literatures about the interaction of ATF4 with the different types of pathological changes in AD brain and pointed out some unsolved problems in this area. We also proposed that a fine regulation of ATF4 in separate neurons or brain regions might be benefit to the therapy of AD.
Collapse
Affiliation(s)
- Na Wei
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
- Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Ling-Qiang Zhu
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
- Department of Pathophysiology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China
| | - Dan Liu
- Institute of Brain Research, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
- Department of Medical Genetics, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, People's Republic of China.
| |
Collapse
|
36
|
Kakegawa T, Takase S, Masubuchi E, Yasukawa K. Diarylheptanoids from Alpinia officinarum Cause Distinct but Overlapping Effects on the Translatome of B Lymphoblastoid Cells. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE : ECAM 2014; 2014:204797. [PMID: 25254051 PMCID: PMC4164264 DOI: 10.1155/2014/204797] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Revised: 07/25/2014] [Accepted: 07/25/2014] [Indexed: 12/01/2022]
Abstract
Diarylheptanoids (AO-0001, AO-0002, and AO-0003) isolated from Alpinia officinarum inhibit proinflammatory mediators and exhibit cytotoxic and antiviral activity. However, the precise mechanisms of action of these diarylheptanoids are unknown as are their effects on expression of specific genes. Here, we used a translatome analysis to investigate the mechanisms and modes of action of these three diarylheptanoids. Polysome-associated messenger RNAs (mRNAs) were prepared from diarylheptanoids-treated and control cells from a human B lymphoblastoid cell line; these mRNA samples were then used for microarray analysis. Microarray Data Analysis Tool version 3.2 was used to analyze the microarray data analysis; this software uses pathway information of the WikiPathways for gene ontology analysis. Each of the diarylheptanoids caused upregulation or downregulation of the same 37 and 286 genes, respectively. Among the 37 upregulated genes, 16 were related to mRNA processing based on the WikiPathways analysis. Our findings provided new insights into the mode of action of diarylheptanoids from A. officinarum.
Collapse
Affiliation(s)
- Tomohito Kakegawa
- Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane, Chiba 283-8555, Japan
| | - Saeko Takase
- Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane, Chiba 283-8555, Japan
| | - Eri Masubuchi
- Faculty of Pharmaceutical Sciences, Josai International University, 1 Gumyo, Togane, Chiba 283-8555, Japan
| | - Ken Yasukawa
- School of Pharmacy, Nihon University, 7-7-1 Narashinodai, Funabashi, Chiba 274-8555, Japan
| |
Collapse
|
37
|
Siu KL, Chan CP, Kok KH, Chiu-Yat Woo P, Jin DY. Suppression of innate antiviral response by severe acute respiratory syndrome coronavirus M protein is mediated through the first transmembrane domain. Cell Mol Immunol 2014; 11:141-9. [PMID: 24509444 PMCID: PMC4003381 DOI: 10.1038/cmi.2013.61] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2013] [Revised: 11/13/2013] [Accepted: 11/27/2013] [Indexed: 12/16/2022] Open
Abstract
Coronaviruses have developed various measures to evade innate immunity. We have previously shown that severe acute respiratory syndrome (SARS) coronavirus M protein suppresses type I interferon (IFN) production by impeding the formation of functional TRAF3-containing complex. In this study, we demonstrate that the IFN-antagonizing activity is specific to SARS coronavirus M protein and is mediated through its first transmembrane domain (TM1) located at the N terminus. M protein from human coronavirus HKU1 does not inhibit IFN production. Whereas N-linked glycosylation of SARS coronavirus M protein has no influence on IFN antagonism, TM1 is indispensable for the suppression of IFN production. TM1 targets SARS coronavirus M protein and heterologous proteins to the Golgi apparatus, yet Golgi localization is required but not sufficient for IFN antagonism. Mechanistically, TM1 is capable of binding with RIG-I, TRAF3, TBK1 and IKKε, and preventing the interaction of TRAF3 with its downstream effectors. Our work defines the molecular architecture of SARS coronavirus M protein required for suppression of innate antiviral response.
Collapse
Affiliation(s)
- Kam-Leung Siu
- Department of Biochemistry, The University of Hong Kong, Pokfulam, Hong Kong
| | - Chi-Ping Chan
- Department of Biochemistry, The University of Hong Kong, Pokfulam, Hong Kong
| | - Kin-Hang Kok
- Department of Biochemistry, The University of Hong Kong, Pokfulam, Hong Kong
| | | | - Dong-Yan Jin
- Department of Biochemistry, The University of Hong Kong, Pokfulam, Hong Kong
| |
Collapse
|
38
|
Comparative analysis of the activation of unfolded protein response by spike proteins of severe acute respiratory syndrome coronavirus and human coronavirus HKU1. Cell Biosci 2014; 4:3. [PMID: 24410900 PMCID: PMC3930072 DOI: 10.1186/2045-3701-4-3] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 10/02/2013] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Whereas severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV) is associated with severe disease, human coronavirus HKU1 (HCoV-HKU1) commonly circulates in the human populations causing generally milder illness. Spike (S) protein of SARS-CoV activates the unfolded protein response (UPR). It is not understood whether HCoV-HKU1 S protein has similar activity. In addition, the UPR-activating domain in SARS-CoV S protein remains to be identified. RESULTS In this study we compared S proteins of SARS-CoV and HCoV-HKU1 for their ability to activate the UPR. Both S proteins were found in the endoplasmic reticulum. Transmembrane serine protease TMPRSS2 catalyzed the cleavage of SARS-CoV S protein, but not the counterpart in HCoV-HKU1. Both S proteins showed a similar pattern of UPR-activating activity. Through PERK kinase they activated the transcription of UPR effector genes such as Grp78, Grp94 and CHOP. N-linked glycosylation was not required for the activation of the UPR by S proteins. S1 subunit of SARS-CoV but not its counterpart in HCoV-HKU1 was capable of activating the UPR. A central region (amino acids 201-400) of SARS-CoV S1 was required for this activity. CONCLUSIONS SARS-CoV and HCoV-HKU1 S proteins use distinct UPR-activating domains to exert the same modulatory effects on UPR signaling.
Collapse
|