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Qadri O, Bashir S, Banday M, Hilal N, Majeed Y, Fatima NI, Pal D, Fazili KM. Tumour suppressor protein sMEK1 links to IRE1 signalling pathway to modulate its activity during ER stress. BIOCHIMICA ET BIOPHYSICA ACTA. MOLECULAR CELL RESEARCH 2024; 1871:119774. [PMID: 38838857 DOI: 10.1016/j.bbamcr.2024.119774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 05/27/2024] [Accepted: 05/28/2024] [Indexed: 06/07/2024]
Abstract
The Endoplasmic Reticulum is a pervasive, dynamic cellular organelle that performs a wide range of functions in the eukaryotic cell, including protein folding and maturation. Upon stress, ER activates an adaptive cellular pathway, namely Unfolded Protein Response, that transduces information from ER to nucleus, restoring homeostasis in the ER milieu. UPR consists of three membrane-tethered sensors; IRE1, PERK and ATF6. Among all the UPR sensors, the IRE1 branch acts as a central pathway that orchestrates several pathways to determine cell fate. However, the detailed knowledge underlying the whole process is not understood yet. Previously, we determined the sMEK1 as one of the interacting partners of IRE1. sMEK1 is a protein phosphatase, which has been indicated in a number of critical cellular functions like apoptosis, cell proliferation, and tumour suppression. In this study, we evaluated the role of sMEK1 on the IRE1 signalling pathway. Our data indicate that sMEK1 can inhibit IRE1 phosphorylation under ER stress. This inhibitory effect of sMEK1 could be reflected in its downstream effectors, Xbp1 and RIDD, which are downregulated in the presence of sMEK1. We also found that the repressing effect of sMEK1 was specific to the IRE1 signalling pathway and could be preserved even under prolonged ER stress. Our findings also indicate that sMEK1 can inhibit IRE1 and its downstream molecules under ER stress irrespective of other UPR sensors. These results help to draw the mechanistic details giving insights into different molecular connections of UPR with other pathways.
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Affiliation(s)
- Ozaira Qadri
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Samirul Bashir
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Mariam Banday
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Nazia Hilal
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Younis Majeed
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Nida I Fatima
- Department of Biotechnology, University of Kashmir, Hazratbal J&K, India
| | - Debnath Pal
- Department of Computational and Data Science (CDS), Indian Institute of Science (IISc), Bengaluru, India
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Le Goupil S, Laprade H, Aubry M, Chevet E. Exploring the IRE1 interactome: From canonical signaling functions to unexpected roles. J Biol Chem 2024; 300:107169. [PMID: 38494075 PMCID: PMC11007444 DOI: 10.1016/j.jbc.2024.107169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 03/04/2024] [Accepted: 03/08/2024] [Indexed: 03/19/2024] Open
Abstract
The unfolded protein response is a mechanism aiming at restoring endoplasmic reticulum (ER) homeostasis and is likely involved in other adaptive pathways. The unfolded protein response is transduced by three proteins acting as sensors and triggering downstream signaling pathways. Among them, inositol-requiring enzyme 1 alpha (IRE1α) (referred to as IRE1 hereafter), an endoplasmic reticulum-resident type I transmembrane protein, exerts its function through both kinase and endoribonuclease activities, resulting in both X-box binding protein 1 mRNA splicing and RNA degradation (regulated ire1 dependent decay). An increasing number of studies have reported protein-protein interactions as regulators of these signaling mechanisms, and additionally, driving other noncanonical functions. In this review, we deliver evolutive and structural insights on IRE1 and further describe how this protein interaction network (interactome) regulates IRE1 signaling abilities or mediates other cellular processes through catalytic-independent mechanisms. Moreover, we focus on newly discovered targets of IRE1 kinase activity and discuss potentially novel IRE1 functions based on the nature of the interactome, thereby identifying new fields to explore regarding this protein's biological roles.
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Affiliation(s)
- Simon Le Goupil
- INSERM U1242, University of Rennes, Rennes, France; Centre de Lutte contre le cancer Eugène Marquis, Rennes, France.
| | - Hadrien Laprade
- INSERM U1242, University of Rennes, Rennes, France; Centre de Lutte contre le cancer Eugène Marquis, Rennes, France
| | - Marc Aubry
- INSERM U1242, University of Rennes, Rennes, France; Centre de Lutte contre le cancer Eugène Marquis, Rennes, France
| | - Eric Chevet
- INSERM U1242, University of Rennes, Rennes, France; Centre de Lutte contre le cancer Eugène Marquis, Rennes, France
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3
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Ham SY, Pyo MJ, Kang M, Kim YS, Lee DH, Chung JH, Lee ST. HSP47 Increases the Expression of Type I Collagen in Fibroblasts through IRE1α Activation, XBP1 Splicing, and Nuclear Translocation of β-Catenin. Cells 2024; 13:527. [PMID: 38534372 DOI: 10.3390/cells13060527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2023] [Revised: 03/13/2024] [Accepted: 03/15/2024] [Indexed: 03/28/2024] Open
Abstract
Heat shock protein 47 (HSP47), also known as SERPINH1, functions as a collagen-specific molecular chaperone protein essential for the formation and stabilization of the collagen triple helix. Here, we delved into the regulatory pathways governed by HSP47, shedding light on collagen homeostasis. Our investigation revealed a significant reduction in HSP47 mRNA levels in the skin tissue of older mice as compared to their younger counterparts. The augmented expression of HSP47 employing lentivirus infection in fibroblasts resulted in an increased secretion of type I collagen. Intriguingly, the elevated expression of HSP47 in fibroblasts correlated with increased protein and mRNA levels of type I collagen. The exposure of fibroblasts to IRE1α RNase inhibitors resulted in the reduced manifestation of HSP47-induced type I collagen secretion and expression. Notably, HSP47-overexpressing fibroblasts exhibited increased XBP1 mRNA splicing. The overexpression of HSP47 or spliced XBP1 facilitated the nuclear translocation of β-catenin and transactivated a reporter harboring TCF binding sites on the promoter. Furthermore, the overexpression of HSP47 or spliced XBP1 or the augmentation of nuclear β-catenin through Wnt3a induced the expression of type I collagen. Our findings substantiate that HSP47 enhances type I collagen expression and secretion in fibroblasts by orchestrating a mechanism that involves an increase in nuclear β-catenin through IRE1α activation and XBP1 splicing. This study therefore presents potential avenues for an anti-skin-aging strategy targeting HSP47-mediated processes.
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Affiliation(s)
- So Young Ham
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Min Ju Pyo
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
| | - Moonkyung Kang
- R&D Center, artiCure Inc., Daejeon 34134, Republic of Korea
| | - Yeon-Soo Kim
- R&D Center, artiCure Inc., Daejeon 34134, Republic of Korea
- Graduate School of New Drug Discovery and Development, Chungnam National University, Daejeon 34134, Republic of Korea
| | - Dong Hun Lee
- Department of Dermatology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
- Laboratory of Cutaneous Aging Research, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Republic of Korea
- Institute of Human-Environment Interface Biology, Seoul National University, Seoul 03080, Republic of Korea
| | - Jin Ho Chung
- Department of Dermatology, Seoul National University College of Medicine, Seoul 03080, Republic of Korea
- Laboratory of Cutaneous Aging Research, Biomedical Research Institute, Seoul National University Hospital, Seoul 03080, Republic of Korea
- Institute of Human-Environment Interface Biology, Seoul National University, Seoul 03080, Republic of Korea
- Institute on Aging, Seoul National University, Seoul 03080, Republic of Korea
| | - Seung-Taek Lee
- Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul 03722, Republic of Korea
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4
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Mahdizadeh SJ, Grandén J, Pelizzari-Raymundo D, Guillory X, Carlesso A, Chevet E, Eriksson LA. Different binding modalities of quercetin to inositol-requiring enzyme 1 of S. cerevisiae and human lead to opposite regulation. Commun Chem 2024; 7:6. [PMID: 38177336 PMCID: PMC10767055 DOI: 10.1038/s42004-023-01092-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 12/20/2023] [Indexed: 01/06/2024] Open
Abstract
The flavonoid Quercetin (Qe) was identified as an activator of Inositol-requiring enzyme 1 (IRE1) in S. cerevisiae (scIre1p), but its impact on human IRE1 (hIRE1) remains controversial due to the absence of a conserved Qe binding site. We have explored the binding modes and effect of Qe on both scIre1p and hIRE1 dimers using in silico and in vitro approaches. The activation site in scIre1p stably accommodates both Qe and its derivative Quercitrin (Qi), thus enhancing the stability of the RNase pocket. However, the corresponding region in hIRE1 does not bind any of the two molecules. Instead, we show that both Qe and Qi block the RNase activity of hIRE1 in vitro, with sub-micromolar IC50 values. Our results provide a rationale for why Qe is an activator in scIre1p but a potent inhibitor in hIRE1. The identification of a new allosteric site in hIRE1 opens a promising window for drug development and UPR modulation.
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Affiliation(s)
- S Jalil Mahdizadeh
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden
| | - Johan Grandén
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden
| | - Diana Pelizzari-Raymundo
- INSERM U1242, Université de Rennes, Rennes, France
- Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Xavier Guillory
- INSERM U1242, Université de Rennes, Rennes, France
- Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
- Univ Rennes, CNRS, ISCR - UMR 6226, F-35000, Rennes, France
| | - Antonio Carlesso
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden
- Department of Pharmacology, Sahlgrenska Academy, University of Gothenburg, SE-405 31, Gothenburg, Sweden
| | - Eric Chevet
- INSERM U1242, Université de Rennes, Rennes, France.
- Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France.
| | - Leif A Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, 405 30, Göteborg, Sweden.
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5
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Bartoszewska S, Sławski J, Collawn JF, Bartoszewski R. Dual RNase activity of IRE1 as a target for anticancer therapies. J Cell Commun Signal 2023:10.1007/s12079-023-00784-5. [PMID: 37721642 DOI: 10.1007/s12079-023-00784-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 08/31/2023] [Indexed: 09/19/2023] Open
Abstract
The unfolded protein response (UPR) is a cellular mechanism that protects cells during stress conditions in which there is an accumulation of misfolded proteins in the endoplasmic reticulum (ER). UPR activates three signaling pathways that function to alleviate stress conditions and promote cellular homeostasis and cell survival. During unmitigated stress conditions, however, UPR activation signaling changes to promote cell death through apoptosis. Interestingly, cancer cells take advantage of this pathway to facilitate survival and avoid apoptosis even during prolonged cell stress conditions. Here, we discuss different signaling pathways associated with UPR and focus specifically on one of the ER signaling pathways activated during UPR, inositol-requiring enzyme 1α (IRE1). The rationale is that the IRE1 pathway is associated with cell fate decisions and recognized as a promising target for cancer therapeutics. Here we discuss IRE1 inhibitors and how they might prove to be an effective cancer therapeutic.
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Affiliation(s)
- Sylwia Bartoszewska
- Department of Inorganic Chemistry, Medical University of Gdansk, Gdansk, Poland
| | - Jakub Sławski
- Department of Biophysics, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a Street, 50-383, Wrocław, Poland
| | - James F Collawn
- Department of Cell, Developmental, and Integrative Biology, University of Alabama at Birmingham, Birmingham, AL, 35233, USA
| | - Rafał Bartoszewski
- Department of Biophysics, Faculty of Biotechnology, University of Wrocław, F. Joliot-Curie 14a Street, 50-383, Wrocław, Poland.
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6
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Tan L, Armstrong AR, Rosas S, Patel CM, Wiele SSV, Willey JS, Carlson CS, Yammani RR. Nuclear protein-1 is the common link for pathways activated by aging and obesity in chondrocytes: A potential therapeutic target for osteoarthritis. FASEB J 2023; 37:e23133. [PMID: 37566478 PMCID: PMC10939173 DOI: 10.1096/fj.202201700rr] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 07/10/2023] [Accepted: 07/27/2023] [Indexed: 08/13/2023]
Abstract
Pathways leading to osteoarthritis (OA) are diverse depending on the risk factors involved; thus, developing OA therapeutics has been challenging. Here we report that nuclear protein-1 (Nupr1), a stress-inducible protein/transcription factor, is activated by pathways associated with obesity and aging in chondrocytes. Treatment of human chondrocytes with free fatty acids (palmitate and oleate; a model for high-fat diet/obesity) induced PERK signaling and increased expression of caspase-3, TRB3, and Nupr1. On the other hand, treatment of chondrocytes with menadione (oxidative stress inducer) induced oxidation of IRE1, activated antioxidant response (higher Nrf2 expression), and increased expression of Nupr1 and matrix metalloproteinases. Experimental OA was induced by destabilization of the medial meniscus (DMM) in the knee joints of Nupr1+/+ and Nupr1-/- mice. Loss of Nupr1 expression reduced the severity of cartilage lesions in this model. Together, our findings suggest that Nupr1 is a common factor activated by signaling pathways activated by obesity (ER stress) and age (oxidative stress) and a potential drug target for OA resulting from various risk factors.
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Affiliation(s)
- Li Tan
- Section of Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Alexandra R. Armstrong
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
| | - Samuel Rosas
- Department of Orthopaedic Surgery, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Chirayu M. Patel
- Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Sabrina S. Vander Wiele
- Department of Biomedical Engineering, The College of New Jersey, Ewing Township, New Jersey, USA
| | - Jeffrey S. Willey
- Department of Radiation Oncology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
| | - Cathy S. Carlson
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
| | - Raghunatha R. Yammani
- Section of Molecular Medicine, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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7
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Zhang M, Wu W, Huang C, Cai T, Wang M, Zhao N, Liu S, Yang S. Interaction of Bmal1 and eIF2α/ATF4 pathway was involved in Shuxie compound alleviation of circadian rhythm disturbance-induced hepatic endoplasmic reticulum stress. JOURNAL OF ETHNOPHARMACOLOGY 2023; 312:116446. [PMID: 37019162 DOI: 10.1016/j.jep.2023.116446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Revised: 03/28/2023] [Accepted: 03/29/2023] [Indexed: 05/08/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Shuxie Compound (SX) combines the composition and efficacy of Suanzaoren decoction and Huanglian Wendan decoction. It can soothe the liver, regulate the qi, nourish the blood and calm the mind. It is used in the clinical treatment of sleep disorder with liver stagnation. Modern studies have proved that circadian rhythm disorder (CRD) can cause sleep deprivation and liver damage, which can be effectively ameliorated by traditional Chinese medicine to soothe the liver stagnation. However, the mechanism of SX is unclear. AIM OF THE STUDY This study was designed to demonstrate the impact of SX on CRD in vivo, and confirm the molecular mechanisms of SX in vitro. MATERIALS AND METHODS The quality of SX and drug-containing serum was controlled by UPLC-Q-TOF/MS, which were used in vivo and in vitro experiments, respectively. In vivo, a light deprivation mouse model was used. In vitro, a stable knockdown Bmal1 cell line was used to explore SX mechanism. RESULTS Low-dose SX (SXL) could restore (1) circadian activity pattern, (2) 24-h basal metabolic pattern, (3) liver injury, and (4) Endoplasmic reticulum (ER) stress in CRD mice. CRD decreased the liver Bmal1 protein at ZT15, which was reversed by SXL treatment. Besides, SXL decreased the mRNA expression of Grp78/ATF4/Chop and the protein expression of ATF4/Chop at ZT11. In vitro experiments, SX reduced the protein expression of thapsigargin (tg)-induced p-eIF2α/ATF4 pathway and increase the viability of AML12 cells by increasing the expression of Bmal1 protein. CONCLUSIONS SXL relieved CRD-induced ER stress and improve cell viability by up-regulating the expression of Bmal1 protein in the liver and then inhibiting the protein expression of p-eIF2α/ATF4.
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Affiliation(s)
- Mengting Zhang
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Wanhong Wu
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Caoxin Huang
- Xiamen Diabetes Institute, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Teng Cai
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Mengyuan Wang
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Nengjiang Zhao
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Suhuan Liu
- Research Center for Translational Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
| | - Shuyu Yang
- Research Studio of Traditional Chinese Medicine, The First Affiliated Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen, 361003, Fujian, China.
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8
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Podinić T, Werstuck G, Raha S. The Implications of Cannabinoid-Induced Metabolic Dysregulation for Cellular Differentiation and Growth. Int J Mol Sci 2023; 24:11003. [PMID: 37446181 DOI: 10.3390/ijms241311003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/15/2023] Open
Abstract
The endocannabinoid system (ECS) governs and coordinates several physiological processes through an integrated signaling network, which is responsible for inducing appropriate intracellular metabolic signaling cascades in response to (endo)cannabinoid stimulation. This intricate cellular system ensures the proper functioning of the immune, reproductive, and nervous systems and is involved in the regulation of appetite, memory, metabolism, and development. Cannabinoid receptors have been observed on both cellular and mitochondrial membranes in several tissues and are stimulated by various classes of cannabinoids, rendering the ECS highly versatile. In the context of growth and development, emerging evidence suggests a crucial role for the ECS in cellular growth and differentiation. Indeed, cannabinoids have the potential to disrupt key energy-sensing metabolic signaling pathways requiring mitochondrial-ER crosstalk, whose functioning is essential for successful cellular growth and differentiation. This review aims to explore the extent of cannabinoid-induced cellular dysregulation and its implications for cellular differentiation.
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Affiliation(s)
- Tina Podinić
- The Department of Pediatrics and the Graduate Program in Medical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
| | - Geoff Werstuck
- Department of Medicine and the Thrombosis and Atherosclerosis Research Institute, David Braley Research Institute, McMaster University, Hamilton, ON L8L 2X2, Canada
| | - Sandeep Raha
- The Department of Pediatrics and the Graduate Program in Medical Sciences, McMaster University, Hamilton, ON L8S 4K1, Canada
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9
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Bashir S, Pal D, Qadri O, Banday M, Fazili K. Quaternary structure analysis of IRE1. MICROPUBLICATION BIOLOGY 2023; 2023:10.17912/micropub.biology.000763. [PMID: 37065768 PMCID: PMC10091119 DOI: 10.17912/micropub.biology.000763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Figures] [Subscribe] [Scholar Register] [Received: 02/05/2023] [Revised: 02/22/2023] [Accepted: 03/27/2023] [Indexed: 04/18/2023]
Abstract
IRE1 belongs to a type I transmembrane protein family harboring two functional domains, cytoplasmic domain with kinase and RNAse catalytic activity, and the luminal domain, which is involved in the sensing of unfolded proteins. IRE1 molecule undergoes dimerization in the lumenal domain, which functionally activates the catalytic C-terminal domain. IRE1 activation is directly related to transition between monomeric and dimeric forms. We have deduced two quaternary structures from the published crystal structure of IRE1. One structure with a large stable interface that requires large activation and deactivation energy to active IRE1. The other quaternary structure has low dissociation energy and is more suitable for IRE1 oligomeric transition.
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Affiliation(s)
- Samirul Bashir
- University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Debnath Pal
- Indian Institute of Science Bangalore, Bengaluru, Karnataka, India
| | - Ozaira Qadri
- University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Mariam Banday
- University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Khalid Fazili
- University of Kashmir, Srinagar, Jammu and Kashmir, India
- Correspondence to: Khalid Fazili (
)
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10
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Wang C, Chang Y, Zhu J, Ma R, Li G. Dual Role of Inositol-requiring Enzyme 1α–X-box Binding protein 1 Signaling in Neurodegenerative Diseases. Neuroscience 2022; 505:157-170. [DOI: 10.1016/j.neuroscience.2022.10.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 10/11/2022] [Accepted: 10/17/2022] [Indexed: 11/05/2022]
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11
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Grey MJ, De Luca H, Ward DV, Kreulen IA, Bugda Gwilt K, Foley SE, Thiagarajah JR, McCormick BA, Turner JR, Lencer WI. The epithelial-specific ER stress sensor ERN2/IRE1β enables host-microbiota crosstalk to affect colon goblet cell development. J Clin Invest 2022; 132:e153519. [PMID: 35727638 PMCID: PMC9435652 DOI: 10.1172/jci153519] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Accepted: 06/16/2022] [Indexed: 11/17/2022] Open
Abstract
Epithelial cells lining mucosal surfaces of the gastrointestinal and respiratory tracts uniquely express ERN2/IRE1β, a paralogue of the most evolutionarily conserved endoplasmic reticulum stress sensor, ERN1/IRE1α. How ERN2 functions at the host-environment interface and why a second paralogue evolved remain incompletely understood. Using conventionally raised and germ-free Ern2-/- mice, we found that ERN2 was required for microbiota-induced goblet cell maturation and mucus barrier assembly in the colon. This occurred only after colonization of the alimentary tract with normal gut microflora, which induced Ern2 expression. ERN2 acted by splicing Xbp1 mRNA to expand ER function and prevent ER stress in goblet cells. Although ERN1 can also splice Xbp1 mRNA, it did not act redundantly to ERN2 in this context. By regulating assembly of the colon mucus layer, ERN2 further shaped the composition of the gut microbiota. Mice lacking Ern2 had a dysbiotic microbial community that failed to induce goblet cell development and increased susceptibility to colitis when transferred into germ-free WT mice. These results show that ERN2 evolved at mucosal surfaces to mediate crosstalk between gut microbes and the colonic epithelium required for normal homeostasis and host defense.
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Affiliation(s)
- Michael J. Grey
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Digestive Disease Center, Boston Children’s Hospital, Boston, Massachusetts, USA
| | - Heidi De Luca
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
| | - Doyle V. Ward
- Department of Microbiology and Physiological Systems, and
- Program in Microbiome Dynamics, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Irini A.M. Kreulen
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
| | - Katlynn Bugda Gwilt
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
| | - Sage E. Foley
- Department of Microbiology and Physiological Systems, and
- Program in Microbiome Dynamics, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Jay R. Thiagarajah
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Digestive Disease Center, Boston Children’s Hospital, Boston, Massachusetts, USA
| | - Beth A. McCormick
- Department of Microbiology and Physiological Systems, and
- Program in Microbiome Dynamics, University of Massachusetts Chan Medical School, Worcester, Massachusetts, USA
| | - Jerrold R. Turner
- Harvard Digestive Disease Center, Boston Children’s Hospital, Boston, Massachusetts, USA
- Laboratory of Mucosal Barrier Pathobiology, Department of Pathology, Brigham and Women’s Hospital, Boston, Massachusetts, USA
- Departments of Pathology and Medicine, Harvard Medical School, Boston, Massachusetts, USA
| | - Wayne I. Lencer
- Division of Gastroenterology and Nutrition, Boston Children’s Hospital, Boston, Massachusetts, USA
- Department of Pediatrics, Harvard Medical School, Boston, Massachusetts, USA
- Harvard Digestive Disease Center, Boston Children’s Hospital, Boston, Massachusetts, USA
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12
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Arter C, Trask L, Ward S, Yeoh S, Bayliss R. Structural features of the protein kinase domain and targeted binding by small-molecule inhibitors. J Biol Chem 2022; 298:102247. [PMID: 35830914 PMCID: PMC9382423 DOI: 10.1016/j.jbc.2022.102247] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 07/04/2022] [Accepted: 07/06/2022] [Indexed: 12/17/2022] Open
Abstract
Protein kinases are key components in cellular signaling pathways as they carry out the phosphorylation of proteins, primarily on Ser, Thr, and Tyr residues. The catalytic activity of protein kinases is regulated, and they can be thought of as molecular switches that are controlled through protein-protein interactions and post-translational modifications. Protein kinases exhibit diverse structural mechanisms of regulation and have been fascinating subjects for structural biologists from the first crystal structure of a protein kinase over 30 years ago, to recent insights into kinase assemblies enabled by the breakthroughs in cryo-EM. Protein kinases are high-priority targets for drug discovery in oncology and other disease settings, and kinase inhibitors have transformed the outcomes of specific groups of patients. Most kinase inhibitors are ATP competitive, deriving potency by occupying the deep hydrophobic pocket at the heart of the kinase domain. Selectivity of inhibitors depends on exploiting differences between the amino acids that line the ATP site and exploring the surrounding pockets that are present in inactive states of the kinase. More recently, allosteric pockets outside the ATP site are being targeted to achieve high selectivity and to overcome resistance to current therapeutics. Here, we review the key regulatory features of the protein kinase family, describe the different types of kinase inhibitors, and highlight examples where the understanding of kinase regulatory mechanisms has gone hand in hand with the development of inhibitors.
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Affiliation(s)
- Chris Arter
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Engineering and Physical Sciences, School of Chemistry, University of Leeds, Leeds, United Kingdom; Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Luke Trask
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Engineering and Physical Sciences, School of Chemistry, University of Leeds, Leeds, United Kingdom; Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Sarah Ward
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Engineering and Physical Sciences, School of Chemistry, University of Leeds, Leeds, United Kingdom
| | - Sharon Yeoh
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom
| | - Richard Bayliss
- Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, United Kingdom; Faculty of Biological Sciences, School of Molecular and Cellular Biology, University of Leeds, Leeds, United Kingdom.
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Amarasinghe KN, Pelizzari-Raymundo D, Carlesso A, Chevet E, Eriksson LA, Jalil Mahdizadeh S. Sensor Dimer Disruption as a new Mode of Action to block the IRE1-mediated Unfolded Protein Response. Comput Struct Biotechnol J 2022; 20:1584-1592. [PMID: 35465159 PMCID: PMC9010685 DOI: 10.1016/j.csbj.2022.03.029] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 03/25/2022] [Accepted: 03/27/2022] [Indexed: 11/03/2022] Open
Abstract
The unfolded protein response (UPR) is activated to cope with an accumulation of improperly folded proteins in the Endoplasmic reticulum (ER). The Inositol requiring enzyme 1α (IRE1α) is the most evolutionary conserved transducer of the UPR. Activated IRE1 forms ‘back-to-back’-dimers that enables the unconventional splicing of X-box Binding Protein 1 (XBP1) mRNA. The spliced XBP1 (XBP1s) mRNA is translated into a transcription factor controlling the expression of UPR target genes. Herein, we report a detailed in silico screening specifically targeting for the first time the dimer interface at the IRE1 RNase region. Using the database of FDA approved drugs, we identified four compounds (neomycin, pemetrexed, quercitrin and rutin) that were able to bind to and distort IRE1 RNase cavity. The activity of the compounds on IRE1 phosphorylation was evaluated in HEK293T cells and on IRE1 RNase activity using an in vitro fluorescence assay. These analyzes revealed sub-micromolar IC50 values. The current study reveals a new and unique mode of action to target and block the IRE1-mediated UPR signaling, whereby we may avoid problems associated with selectivity occurring when targeting the IRE1 kinase pocket as well as the inherent reactivity of covalent inhibitors targeting the RNase pocket.
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14
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Decoding non-canonical mRNA decay by the endoplasmic-reticulum stress sensor IRE1α. Nat Commun 2021; 12:7310. [PMID: 34911951 PMCID: PMC8674358 DOI: 10.1038/s41467-021-27597-7] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 11/24/2021] [Indexed: 12/21/2022] Open
Abstract
Inositol requiring enzyme 1 (IRE1) mitigates endoplasmic-reticulum (ER) stress by orchestrating the unfolded-protein response (UPR). IRE1 spans the ER membrane, and signals through a cytosolic kinase-endoribonuclease module. The endoribonuclease generates the transcription factor XBP1s by intron excision between similar RNA stem-loop endomotifs, and depletes select cellular mRNAs through regulated IRE1-dependent decay (RIDD). Paradoxically, in mammals RIDD seems to target only mRNAs with XBP1-like endomotifs, while in flies RIDD exhibits little sequence restriction. By comparing nascent and total IRE1α-controlled mRNAs in human cells, we identify not only canonical endomotif-containing RIDD substrates, but also targets without such motifs-degraded by a process we coin RIDDLE, for RIDD lacking endomotif. IRE1α displays two basic endoribonuclease modalities: highly specific, endomotif-directed cleavage, minimally requiring dimers; and more promiscuous, endomotif-independent processing, requiring phospho-oligomers. An oligomer-deficient IRE1α mutant fails to support RIDDLE in vitro and in cells. Our results advance current mechanistic understanding of the UPR.
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15
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Pharmacological targeting of endoplasmic reticulum stress in disease. Nat Rev Drug Discov 2021; 21:115-140. [PMID: 34702991 DOI: 10.1038/s41573-021-00320-3] [Citation(s) in RCA: 199] [Impact Index Per Article: 66.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/15/2021] [Indexed: 02/08/2023]
Abstract
The accumulation of misfolded proteins in the endoplasmic reticulum (ER) leads to ER stress, resulting in activation of the unfolded protein response (UPR) that aims to restore protein homeostasis. However, the UPR also plays an important pathological role in many diseases, including metabolic disorders, cancer and neurological disorders. Over the last decade, significant effort has been invested in targeting signalling proteins involved in the UPR and an array of drug-like molecules is now available. However, these molecules have limitations, the understanding of which is crucial for their development into therapies. Here, we critically review the existing ER stress and UPR-directed drug-like molecules, highlighting both their value and their limitations.
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16
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Structural and molecular bases to IRE1 activity modulation. Biochem J 2021; 478:2953-2975. [PMID: 34375386 DOI: 10.1042/bcj20200919] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 07/06/2021] [Accepted: 07/12/2021] [Indexed: 12/13/2022]
Abstract
The Unfolded Protein response is an adaptive pathway triggered upon alteration of endoplasmic reticulum (ER) homeostasis. It is transduced by three major ER stress sensors, among which the Inositol Requiring Enzyme 1 (IRE1) is the most evolutionarily conserved. IRE1 is an ER-resident type I transmembrane protein exhibiting an ER luminal domain that senses the protein folding status and a catalytic kinase and RNase cytosolic domain. In recent years, IRE1 has emerged as a relevant therapeutic target in various diseases including degenerative, inflammatory and metabolic pathologies and cancer. As such several drugs altering IRE1 activity were developed that target either catalytic activity and showed some efficacy in preclinical pathological mouse models. In this review, we describe the different drugs identified to target IRE1 activity as well as their mode of action from a structural perspective, thereby identifying common and different modes of action. Based on this information we discuss on how new IRE1-targeting drugs could be developed that outperform the currently available molecules.
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17
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Li W, Crotty K, Garrido Ruiz D, Voorhies M, Rivera C, Sil A, Mullins RD, Jacobson MP, Peschek J, Walter P. Protomer alignment modulates specificity of RNA substrate recognition by Ire1. eLife 2021; 10:e67425. [PMID: 33904404 PMCID: PMC8104961 DOI: 10.7554/elife.67425] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/27/2021] [Indexed: 11/21/2022] Open
Abstract
The unfolded protein response (UPR) maintains protein folding homeostasis in the endoplasmic reticulum (ER). In metazoan cells, the Ire1 branch of the UPR initiates two functional outputs-non-conventional mRNA splicing and selective mRNA decay (RIDD). By contrast, Ire1 orthologs from Saccharomyces cerevisiae and Schizosaccharomyces pombe are specialized for only splicing or RIDD, respectively. Previously, we showed that the functional specialization lies in Ire1's RNase activity, which is either stringently splice-site specific or promiscuous (Li et al., 2018). Here, we developed an assay that reports on Ire1's RNase promiscuity. We found that conversion of two amino acids within the RNase domain of S. cerevisiae Ire1 to their S. pombe counterparts rendered it promiscuous. Using biochemical assays and computational modeling, we show that the mutations rewired a pair of salt bridges at Ire1 RNase domain's dimer interface, changing its protomer alignment. Thus, Ire1 protomer alignment affects its substrates specificity.
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Affiliation(s)
- Weihan Li
- Department of Biochemistry and Biophysics, University of California San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteSan FranciscoUnited States
| | - Kelly Crotty
- Department of Biochemistry and Biophysics, University of California San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteSan FranciscoUnited States
| | - Diego Garrido Ruiz
- Department of Pharmaceutical Chemistry, University of California at San FranciscoSan FranciscoUnited States
| | - Mark Voorhies
- Department of Microbiology and Immunology, University of California at San FranciscoSan FranciscoUnited States
| | - Carlos Rivera
- Department of Molecular Biophysics and Biochemistry, Yale School of MedicineNew HavenUnited States
| | - Anita Sil
- Department of Microbiology and Immunology, University of California at San FranciscoSan FranciscoUnited States
| | - R Dyche Mullins
- Howard Hughes Medical InstituteSan FranciscoUnited States
- Department of Cellular and Molecular Pharmacology, University of California at San FranciscoSan FranciscoUnited States
| | - Matthew P Jacobson
- Department of Pharmaceutical Chemistry, University of California at San FranciscoSan FranciscoUnited States
| | - Jirka Peschek
- Department of Biochemistry and Biophysics, University of California San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteSan FranciscoUnited States
| | - Peter Walter
- Department of Biochemistry and Biophysics, University of California San FranciscoSan FranciscoUnited States
- Howard Hughes Medical InstituteSan FranciscoUnited States
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18
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The Structure, Activation and Signaling of IRE1 and Its Role in Determining Cell Fate. Biomedicines 2021; 9:biomedicines9020156. [PMID: 33562589 PMCID: PMC7914947 DOI: 10.3390/biomedicines9020156] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/22/2021] [Accepted: 02/02/2021] [Indexed: 02/06/2023] Open
Abstract
Inositol-requiring enzyme type 1 (IRE1) is a serine/threonine kinase acting as one of three branches of the Unfolded Protein Response (UPR) signaling pathway, which is activated upon endoplasmic reticulum (ER) stress conditions. It is known to be capable of inducing both pro-survival and pro-apoptotic cellular responses, which are strictly related to numerous human pathologies. Among others, IRE1 activity has been confirmed to be increased in cancer, neurodegeneration, inflammatory and metabolic disorders, which are associated with an accumulation of misfolded proteins within ER lumen and the resulting ER stress conditions. Emerging evidence suggests that genetic or pharmacological modulation of IRE1 may have a significant impact on cell viability, and thus may be a promising step forward towards development of novel therapeutic strategies. In this review, we extensively describe the structural analysis of IRE1 molecule, the molecular dynamics associated with IRE1 activation, and interconnection between it and the other branches of the UPR with regard to its potential use as a therapeutic target. Detailed knowledge of the molecular characteristics of the IRE1 protein and its activation may allow the design of specific kinase or RNase modulators that may act as drug candidates.
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19
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Pillon MC, Gordon J, Frazier MN, Stanley RE. HEPN RNases - an emerging class of functionally distinct RNA processing and degradation enzymes. Crit Rev Biochem Mol Biol 2021; 56:88-108. [PMID: 33349060 PMCID: PMC7856873 DOI: 10.1080/10409238.2020.1856769] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Revised: 11/06/2020] [Accepted: 11/24/2020] [Indexed: 10/22/2022]
Abstract
HEPN (Higher Eukaryotes and Prokaryotes Nucleotide-binding) RNases are an emerging class of functionally diverse RNA processing and degradation enzymes. Members are defined by a small α-helical bundle encompassing a short consensus RNase motif. HEPN dimerization is a universal requirement for RNase activation as the conserved RNase motifs are precisely positioned at the dimer interface to form a composite catalytic center. While the core HEPN fold is conserved, the organization surrounding the HEPN dimer can support large structural deviations that contribute to their specialized functions. HEPN RNases are conserved throughout evolution and include bacterial HEPN RNases such as CRISPR-Cas and toxin-antitoxin associated nucleases, as well as eukaryotic HEPN RNases that adopt large multi-component machines. Here we summarize the canonical elements of the growing HEPN RNase family and identify molecular features that influence RNase function and regulation. We explore similarities and differences between members of the HEPN RNase family and describe the current mechanisms for HEPN RNase activation and inhibition.
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Affiliation(s)
- Monica C. Pillon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Jacob Gordon
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Meredith N. Frazier
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
| | - Robin E. Stanley
- Signal Transduction Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, Department of Health and Human Services, 111 T. W. Alexander Drive, Research Triangle Park, NC 27709, USA
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20
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Li Z, Howell SH. Review: The two faces of IRE1 and their role in protecting plants from stress. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2021; 303:110758. [PMID: 33487343 DOI: 10.1016/j.plantsci.2020.110758] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Revised: 11/10/2020] [Accepted: 11/11/2020] [Indexed: 05/23/2023]
Abstract
IRE1 is a key factor in the Unfolded Protein Response (UPR) in plants. IRE1 is a single-pass transmembrane protein that has a lumenal domain (LD) and cytoplasmic domain (CD), which perform quite different tasks on different sides of the ER membrane. The LD recognizes the presence of misfolded proteins in the ER lumen. The LDs of IRE1 in different plant species are predicted to fold into β-propeller structures with surfaces for protein-protein interactions. Likewise, the CDs of plant IRE1s have predicted structural interfaces that promote the face-to-face arrangements of IRE1 for transphosphorylation and back-to-back arrangements for RNA splicing. Hence, the structures on the different faces of plant IRE1s have unique features for recognizing problems of protein folding in the ER and transducing that signal to activate the UPR.
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Affiliation(s)
- Zhaoxia Li
- Plant Sciences Institute, Iowa State University, Ames, Iowa, USA
| | - Stephen H Howell
- Plant Sciences Institute, Iowa State University, Ames, Iowa, USA.
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21
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Evolution and function of the epithelial cell-specific ER stress sensor IRE1β. Mucosal Immunol 2021; 14:1235-1246. [PMID: 34075183 PMCID: PMC8528705 DOI: 10.1038/s41385-021-00412-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/30/2021] [Accepted: 05/01/2021] [Indexed: 02/04/2023]
Abstract
Barrier epithelial cells lining the mucosal surfaces of the gastrointestinal and respiratory tracts interface directly with the environment. As such, these tissues are continuously challenged to maintain a healthy equilibrium between immunity and tolerance against environmental toxins, food components, and microbes. An extracellular mucus barrier, produced and secreted by the underlying epithelium plays a central role in this host defense response. Several dedicated molecules with a unique tissue-specific expression in mucosal epithelia govern mucosal homeostasis. Here, we review the biology of Inositol-requiring enzyme 1β (IRE1β), an ER-resident endonuclease and paralogue of the most evolutionarily conserved ER stress sensor IRE1α. IRE1β arose through gene duplication in early vertebrates and adopted functions unique from IRE1α which appear to underlie the basic development and physiology of mucosal tissues.
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22
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Activation of the IRE1 RNase through remodeling of the kinase front pocket by ATP-competitive ligands. Nat Commun 2020; 11:6387. [PMID: 33318494 PMCID: PMC7736581 DOI: 10.1038/s41467-020-19974-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 11/09/2020] [Indexed: 12/22/2022] Open
Abstract
Inositol-Requiring Enzyme 1 (IRE1) is an essential component of the Unfolded Protein Response. IRE1 spans the endoplasmic reticulum membrane, comprising a sensory lumenal domain, and tandem kinase and endoribonuclease (RNase) cytoplasmic domains. Excess unfolded proteins in the ER lumen induce dimerization and oligomerization of IRE1, triggering kinase trans-autophosphorylation and RNase activation. Known ATP-competitive small-molecule IRE1 kinase inhibitors either allosterically disrupt or stabilize the active dimeric unit, accordingly inhibiting or stimulating RNase activity. Previous allosteric RNase activators display poor selectivity and/or weak cellular activity. In this study, we describe a class of ATP-competitive RNase activators possessing high selectivity and strong cellular activity. This class of activators binds IRE1 in the kinase front pocket, leading to a distinct conformation of the activation loop. Our findings reveal exquisitely precise interdomain regulation within IRE1, advancing the mechanistic understanding of this important enzyme and its investigation as a potential small-molecule therapeutic target. The RNase activity of Inositol-Requiring Enzyme 1 (IRE1) can be allosterically regulated by ATP-competitive inhibitors of the IRE1 kinase domain. Here, the authors identify ATP-competitive IRE1 RNase activators with improved selectivity and cellular activity, and elucidate their mechanism of action.
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23
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Duzgun Z, Eroglu Z. Role of cardiac drugs and flavonoids on the IRE1-JNK pathway as revealed by re-ranked molecular docking scores, MM/PBSA and umbrella sampling. J Biomol Struct Dyn 2020; 40:3428-3450. [PMID: 33251987 DOI: 10.1080/07391102.2020.1851299] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
One of the important causes of cardiac dysfunction is the triggering of apoptosis through the IRE1-JNK signaling pathway due to excessive ER stress (endoplasmic reticulum stress). Although there are various studies on beneficial or harmful side effects of cardiac drugs, knowledge about the molecular mechanism of their interactions on this pathway is very limited. In this study, we investigated interactions of statins, ace inhibitors, antiarrhythmic drugs and flavonoids in IRE1, ASK1(apoptosis signal-regulating kinase 1) and JNK1 at an atomic level in comparison with their well-known inhibitors. The rank of scores obtained from four different docking algorithms (Autodock 4, Autodock Vina, iGEMDOCK and GOLD) were combined so that they could be compared with each other and evaluated together. According to combined results, the most potent compound for each compound group was selected for molecular dynamics simulations, MM/PBSA (molecular mechanics/Poisson-Boltzmann surface area) and umbrella sampling calculations. We observed that the statin group drugs had the best affinity by interacting with ASK1 and JNK1 by having a similar effect with their inhibitors, and atorvastatin and pitavastatin came to the fore. Norizalpinine from the flavonoid group had a strong binding interaction with IRE1, and amiodarone from the antiarrhythmic drug group had high binding affinities with IRE1, ASK1 and JNK1. Our study has shown that atorvastatin, pitavastatin, norizalpinine and amiodarone may have a role in preventing cardiac dysfunctions caused by ER stress and may shed light on further in vitro and in vivo research.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Zekeriya Duzgun
- Faculty of Medicine, Department of Medical Biology, Giresun University, Giresun, Turkey
| | - Zuhal Eroglu
- Faculty of Medicine, Department of Medical Biology, Ege University, Izmir, Turkey
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24
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Bashir S, Banday M, Qadri O, Bashir A, Hilal N, Nida-I-Fatima, Rader S, Fazili KM. The molecular mechanism and functional diversity of UPR signaling sensor IRE1. Life Sci 2020; 265:118740. [PMID: 33188833 DOI: 10.1016/j.lfs.2020.118740] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 11/03/2020] [Accepted: 11/06/2020] [Indexed: 02/06/2023]
Abstract
The endoplasmic reticulum is primarily responsible for protein folding and maturation. However, the organelle is subject to varied stress conditions from time to time, which lead to the activation of a signaling program known as the Unfolded Protein Response (UPR) pathway. This pathway, upon sensing any disturbance in the protein-folding milieu sends signals to the nucleus and cytoplasm in order to restore homeostasis. One of the prime UPR signaling sensors is Inositol-requiring enzyme 1 (IRE1); an ER membrane embedded protein with dual enzyme activities, kinase and endoribonuclease. The ribonuclease activity of IRE1 results in Xbp1 splicing in mammals or Hac1 splicing in yeast. However, IRE1 can switch its substrate specificity to the mRNAs that are co-transnationally transported to the ER, a phenomenon known as Regulated IRE1 Dependent Decay (RIDD). IRE1 is also reported to act as a principal molecule that coordinates with other proteins and signaling pathways, which in turn might be responsible for its regulation. The current review highlights studies on IRE1 explaining the structural features and molecular mechanism behind its ribonuclease outputs. The emphasis is also laid on the molecular effectors, which directly or indirectly interact with IRE1 to either modulate its function or connect it to other pathways. This is important in understanding the functional pleiotropy of IRE1, by which it can switch its activity from pro-survival to pro-apoptotic, thus determining the fate of cells.
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Affiliation(s)
- Samirul Bashir
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Mariam Banday
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Ozaira Qadri
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Arif Bashir
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Nazia Hilal
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Nida-I-Fatima
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India
| | - Stephen Rader
- Department of Chemistry, University of Northern British Columbia, Prince George, BC, Canada
| | - Khalid Majid Fazili
- Department of Biotechnology, University of Kashmir, Srinagar, Jammu and Kashmir, India.
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25
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Dasgupta D, Nakao Y, Mauer AS, Thompson JM, Sehrawat TS, Liao CY, Krishnan A, Lucien F, Guo Q, Liu M, Xue F, Fukushima M, Katsumi T, Bansal A, Pandey MK, Maiers JL, DeGrado T, Ibrahim SH, Revzin A, Pavelko KD, Barry MA, Kaufman RJ, Malhi H. IRE1A Stimulates Hepatocyte-Derived Extracellular Vesicles That Promote Inflammation in Mice With Steatohepatitis. Gastroenterology 2020; 159:1487-1503.e17. [PMID: 32574624 PMCID: PMC7666601 DOI: 10.1053/j.gastro.2020.06.031] [Citation(s) in RCA: 115] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Revised: 05/14/2020] [Accepted: 06/11/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND & AIMS Endoplasmic reticulum to nucleus signaling 1 (ERN1, also called IRE1A) is a sensor of the unfolded protein response that is activated in the livers of patients with nonalcoholic steatohepatitis (NASH). Hepatocytes release ceramide-enriched inflammatory extracellular vesicles (EVs) after activation of IRE1A. We studied the effects of inhibiting IRE1A on release of inflammatory EVs in mice with diet-induced steatohepatitis. METHODS C57BL/6J mice and mice with hepatocyte-specific disruption of Ire1a (IRE1αΔhep) were fed a diet high in fat, fructose, and cholesterol to induce development of steatohepatitis or a standard chow diet (controls). Some mice were given intraperitoneal injections of the IRE1A inhibitor 4μ8C. Mouse liver and primary hepatocytes were transduced with adenovirus or adeno-associated virus that expressed IRE1A. Livers were collected from mice and analyzed by quantitative polymerase chain reaction and chromatin immunoprecipitation assays; plasma samples were analyzed by enzyme-linked immunosorbent assay. EVs were derived from hepatocytes and injected intravenously into mice. Plasma EVs were characterized by nanoparticle-tracking analysis, electron microscopy, immunoblots, and nanoscale flow cytometry; we used a membrane-tagged reporter mouse to detect hepatocyte-derived EVs. Plasma and liver tissues from patients with NASH and without NASH (controls) were analyzed for EV concentration and by RNAscope and gene expression analyses. RESULTS Disruption of Ire1a in hepatocytes or inhibition of IRE1A reduced the release of EVs and liver injury, inflammation, and accumulation of macrophages in mice on the diet high in fat, fructose, and cholesterol. Activation of IRE1A, in the livers of mice, stimulated release of hepatocyte-derived EVs, and also from cultured primary hepatocytes. Mice given intravenous injections of IRE1A-stimulated, hepatocyte-derived EVs accumulated monocyte-derived macrophages in the liver. IRE1A-stimulated EVs were enriched in ceramides. Chromatin immunoprecipitation showed that IRE1A activated X-box binding protein 1 (XBP1) to increase transcription of serine palmitoyltransferase genes, which encode the rate-limiting enzyme for ceramide biosynthesis. Administration of a pharmacologic inhibitor of serine palmitoyltransferase to mice reduced the release of EVs. Levels of XBP1 and serine palmitoyltransferase were increased in liver tissues, and numbers of EVs were increased in plasma, from patients with NASH compared with control samples and correlated with the histologic features of inflammation. CONCLUSIONS In mouse hepatocytes, activated IRE1A promotes transcription of serine palmitoyltransferase genes via XBP1, resulting in ceramide biosynthesis and release of EVs. The EVs recruit monocyte-derived macrophages to the liver, resulting in inflammation and injury in mice with diet-induced steatohepatitis. Levels of XBP1, serine palmitoyltransferase, and EVs are all increased in liver tissues from patients with NASH. Strategies to block this pathway might be developed to reduce liver inflammation in patients with NASH.
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Affiliation(s)
- Debanjali Dasgupta
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Yasuhiko Nakao
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905,Department of Gastroenterology and Hepatology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Amy S Mauer
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Jill M Thompson
- Department of Molecular Medicine, Mayo Clinic, Rochester, MN 55905
| | - Tejasav S Sehrawat
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Chieh-Yu Liao
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Anuradha Krishnan
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | | | - Qianqian Guo
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Mengfei Liu
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Fei Xue
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Masanori Fukushima
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905,Department of Gastroenterology and Hepatology, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1 Sakamoto, Nagasaki, 852-8501, Japan
| | - Tomohiro Katsumi
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905,2-2-2 Iidanishi Yamagata city, Yamagata, Japan 990-9585 Yamagata University Faculty of Medicine, Department of Gastroenterology
| | - Aditya Bansal
- Department of Radiology, Mayo Clinic, Rochester, MN 55905
| | | | - Jessica L Maiers
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | | | - Samar H Ibrahim
- Division of Pediatric Gastroenterology, Mayo Clinic, Rochester, MN 55905
| | - Alexander Revzin
- Department of Physiology and Biomedical Engineering, Mayo Clinic, Rochester, MN 55905
| | | | - Michael A Barry
- Division of Infectious Diseases, Department of Medicine, Mayo Clinic, Rochester, MN 55905
| | - Randal J Kaufman
- Center for Neuroscience, Aging, and Stem Cell Research, Sanford Burnham Prebys Medical Discovery Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037
| | - Harmeet Malhi
- Division of Gastroenterology and Hepatology, Department of Medicine, Mayo Clinic, Rochester, Minnesota.
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26
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Grandjean JMD, Madhavan A, Cech L, Seguinot BO, Paxman RJ, Smith E, Scampavia L, Powers ET, Cooley CB, Plate L, Spicer TP, Kelly JW, Wiseman RL. Pharmacologic IRE1/XBP1s activation confers targeted ER proteostasis reprogramming. Nat Chem Biol 2020; 16:1052-1061. [PMID: 32690944 PMCID: PMC7502540 DOI: 10.1038/s41589-020-0584-z] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Accepted: 06/05/2020] [Indexed: 12/14/2022]
Abstract
Activation of the IRE1/XBP1s signaling arm of the unfolded protein response (UPR) is a promising strategy to correct defects in endoplasmic reticulum (ER) proteostasis implicated in diverse diseases. However, no pharmacologic activators of this pathway identified to date are suitable for ER proteostasis remodeling through selective activation of IRE1/XBP1s signaling. Here, we use high-throughput screening to identify non-toxic compounds that induce ER proteostasis remodeling through IRE1/XBP1s activation. We employ transcriptional profiling to stringently confirm that our prioritized compounds selectively activate IRE1/XBP1s signaling without activating other cellular stress-responsive signaling pathways. Furthermore, we demonstrate that our compounds improve ER proteostasis of destabilized variants of amyloid precursor protein (APP) through an IRE1-dependent mechanism and reduce APP-associated mitochondrial toxicity in cellular models. These results establish highly selective IRE1/XBP1s activating compounds that can be widely employed to define the functional importance of IRE1/XBP1s activity for ER proteostasis regulation in the context of health and disease.
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Affiliation(s)
- Julia M D Grandjean
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Aparajita Madhavan
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Lauren Cech
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Bryan O Seguinot
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA
| | - Ryan J Paxman
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | - Emery Smith
- Scripps Research Molecular Screening Center, The Scripps Research Institute, Jupiter, FL, USA
| | - Louis Scampavia
- Scripps Research Molecular Screening Center, The Scripps Research Institute, Jupiter, FL, USA
| | - Evan T Powers
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
| | | | - Lars Plate
- Departments of Chemistry and Biological Sciences, Vanderbilt University, Nashville, TN, USA
| | - Timothy P Spicer
- Scripps Research Molecular Screening Center, The Scripps Research Institute, Jupiter, FL, USA
| | - Jeffery W Kelly
- Department of Chemistry, The Scripps Research Institute, La Jolla, CA, USA
- The Skaggs Institute for Chemical Biology, The Scripps Research Institute, La Jolla, CA, USA
| | - R Luke Wiseman
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, USA.
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27
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Raymundo DP, Doultsinos D, Guillory X, Carlesso A, Eriksson LA, Chevet E. Pharmacological Targeting of IRE1 in Cancer. Trends Cancer 2020; 6:1018-1030. [PMID: 32861679 DOI: 10.1016/j.trecan.2020.07.006] [Citation(s) in RCA: 58] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/06/2020] [Accepted: 07/20/2020] [Indexed: 12/20/2022]
Abstract
IRE1α (inositol requiring enzyme 1 alpha) is one of the main transducers of the unfolded protein response (UPR). IRE1α plays instrumental protumoral roles in several cancers, and high IRE1α activity has been associated with poorer prognoses. In this context, IRE1α has been identified as a potentially relevant therapeutic target. Pharmacological inhibition of IRE1α activity can be achieved by targeting either the kinase domain or the RNase domain. Herein, the recent advances in IRE1α pharmacological targeting is summarized. We describe the identification and optimization of IRE1α inhibitors as well as their mode of action and limitations as anticancer drugs. The potential pitfalls and challenges that could be faced in the clinic, and the opportunities that IRE1α modulating strategies may present are discussed.
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Affiliation(s)
- Diana Pelizzari Raymundo
- Proteostasis and Cancer Team, INSERM U1242, COSS Laboratory, Université de Rennes, Rennes, France; Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Dimitrios Doultsinos
- Proteostasis and Cancer Team, INSERM U1242, COSS Laboratory, Université de Rennes, Rennes, France; Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Xavier Guillory
- Institut des Science Chimiques de Rennes, CNRS UMR6226, Université de Rennes, Rennes, France
| | - Antonio Carlesso
- Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden
| | - Leif A Eriksson
- Department of Chemistry and Molecular Biology, University of Gothenburg, Göteborg, Sweden.
| | - Eric Chevet
- Proteostasis and Cancer Team, INSERM U1242, COSS Laboratory, Université de Rennes, Rennes, France; Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France.
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28
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Yeung W, Ruan Z, Kannan N. Emerging roles of the αC-β4 loop in protein kinase structure, function, evolution, and disease. IUBMB Life 2020; 72:1189-1202. [PMID: 32101380 DOI: 10.1002/iub.2253] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 02/07/2020] [Indexed: 12/11/2022]
Abstract
The faithful propagation of cellular signals in most organisms relies on the coordinated functions of a large family of protein kinases that share a conserved catalytic domain. The catalytic domain is a dynamic scaffold that undergoes large conformational changes upon activation. Most of these conformational changes, such as movement of the regulatory αC-helix from an "out" to "in" conformation, hinge on a conserved, but understudied, loop termed the αC-β4 loop, which mediates conserved interactions to tether flexible structural elements to the kinase core. We previously showed that the αC-β4 loop is a unique feature of eukaryotic protein kinases. Here, we review the emerging roles of this loop in kinase structure, function, regulation, and diseases. Through a kinome-wide analysis, we define the boundaries of the loop for the first time and show that sequence and structural variation in the loop correlate with conformational and regulatory variation. Many recurrent disease mutations map to the αC-β4 loop and contribute to drug resistance and abnormal kinase activation by relieving key auto-inhibitory interactions associated with αC-helix and inter-lobe movement. The αC-β4 loop is a hotspot for post-translational modifications, protein-protein interaction, and Hsp90 mediated folding. Our kinome-wide analysis provides insights for hypothesis-driven characterization of understudied kinases and the development of allosteric protein kinase inhibitors.
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Affiliation(s)
- Wayland Yeung
- Institute of Bioinformatics, University of Georgia, Athens, Georgia
| | - Zheng Ruan
- Institute of Bioinformatics, University of Georgia, Athens, Georgia
| | - Natarajan Kannan
- Institute of Bioinformatics, University of Georgia, Athens, Georgia.,Department of Biochemistry & Molecular Biology, University of Georgia, Athens, Georgia
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29
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Feldman HC, Vidadala VN, Potter ZE, Papa FR, Backes BJ, Maly DJ. Development of a Chemical Toolset for Studying the Paralog-Specific Function of IRE1. ACS Chem Biol 2019; 14:2595-2605. [PMID: 31609569 PMCID: PMC6925334 DOI: 10.1021/acschembio.9b00482] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The dual kinase endoribonuclease IRE1 is a master regulator of cell fate decisions in cells experiencing endoplasmic reticulum (ER) stress. In mammalian cells, there are two paralogs of IRE1: IRE1α and IRE1β. While IRE1α has been extensively studied, much less is understood about IRE1β and its role in signaling. In addition, whether the regulation of IRE1β's enzymatic activities varies compared to IRE1α is not known. Here, we show that the RNase domain of IRE1β is enzymatically active and capable of cleaving an XBP1 RNA mini-substrate in vitro. Using ATP-competitive inhibitors, we find that, like IRE1α, there is an allosteric relationship between the kinase and RNase domains of IRE1β. This allowed us to develop a novel toolset of both paralog specific and dual-IRE1α/β kinase inhibitors that attenuate RNase activity (KIRAs). Using sequence alignments of IRE1α and IRE1β, we propose a model for paralog-selective inhibition through interactions with nonconserved residues that differentiate the ATP-binding pockets of IRE1α and IRE1β.
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Affiliation(s)
- Hannah C. Feldman
- Department of Chemistry, University of Washington, Seattle, Washington, United States
| | | | - Zachary E. Potter
- Department of Chemistry, University of Washington, Seattle, Washington, United States
| | - Feroz R. Papa
- Department of Medicine, University of California−San Francisco, San Francisco, California, United States
- Lung Biology Center, University of California−San Francisco, San Francisco, California, United States
- Department of Pathology, University of California−San Francisco, San Francisco, California, United States
- Diabetes Center, University of California−San Francisco, San Francisco, California, United States
- California Institute for Quantitative Biosciences, University of California−San Francisco, San Francisco, California, United States
| | - Bradley J. Backes
- Department of Medicine, University of California−San Francisco, San Francisco, California, United States
- Lung Biology Center, University of California−San Francisco, San Francisco, California, United States
| | - Dustin J. Maly
- Department of Chemistry, University of Washington, Seattle, Washington, United States
- Department of Biochemistry, University of Washington, Seattle, Washington, United States
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30
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Wood KA, Rowlands CF, Qureshi WMS, Thomas HB, Buczek WA, Briggs TA, Hubbard SJ, Hentges KE, Newman WG, O’Keefe RT. Disease modeling of core pre-mRNA splicing factor haploinsufficiency. Hum Mol Genet 2019; 28:3704-3723. [PMID: 31304552 PMCID: PMC6935387 DOI: 10.1093/hmg/ddz169] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/04/2019] [Accepted: 07/08/2019] [Indexed: 12/12/2022] Open
Abstract
The craniofacial disorder mandibulofacial dysostosis Guion-Almeida type is caused by haploinsufficiency of the U5 snRNP gene EFTUD2/SNU114. However, it is unclear how reduced expression of this core pre-mRNA splicing factor leads to craniofacial defects. Here we use a CRISPR-Cas9 nickase strategy to generate a human EFTUD2-knockdown cell line and show that reduced expression of EFTUD2 leads to diminished proliferative ability of these cells, increased sensitivity to endoplasmic reticulum (ER) stress and the mis-expression of several genes involved in the ER stress response. RNA-Seq analysis of the EFTUD2-knockdown cell line revealed transcriptome-wide changes in gene expression, with an enrichment for genes associated with processes involved in craniofacial development. Additionally, our RNA-Seq data identified widespread mis-splicing in EFTUD2-knockdown cells. Analysis of the functional and physical characteristics of mis-spliced pre-mRNAs highlighted conserved properties, including length and splice site strengths, of retained introns and skipped exons in our disease model. We also identified enriched processes associated with the affected genes, including cell death, cell and organ morphology and embryonic development. Together, these data support a model in which EFTUD2 haploinsufficiency leads to the mis-splicing of a distinct subset of pre-mRNAs with a widespread effect on gene expression, including altering the expression of ER stress response genes and genes involved in the development of the craniofacial region. The increased burden of unfolded proteins in the ER resulting from mis-splicing would exceed the capacity of the defective ER stress response, inducing apoptosis in cranial neural crest cells that would result in craniofacial abnormalities during development.
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Affiliation(s)
- Katherine A Wood
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
- Center for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, St. Mary’s Hospital, The University of Manchester, Manchester Academic Health Science Centre Manchester, M13 9PT, UK
| | - Charlie F Rowlands
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
- Center for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, St. Mary’s Hospital, The University of Manchester, Manchester Academic Health Science Centre Manchester, M13 9PT, UK
| | - Wasay Mohiuddin Shaikh Qureshi
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
| | - Huw B Thomas
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
| | - Weronika A Buczek
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
| | - Tracy A Briggs
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
- Center for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, St. Mary’s Hospital, The University of Manchester, Manchester Academic Health Science Centre Manchester, M13 9PT, UK
| | - Simon J Hubbard
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
| | - Kathryn E Hentges
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
| | - William G Newman
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
- Center for Genomic Medicine, Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, St. Mary’s Hospital, The University of Manchester, Manchester Academic Health Science Centre Manchester, M13 9PT, UK
| | - Raymond T O’Keefe
- Division of Evolution and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester
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31
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Mayo CB, Erlandsen H, Mouser DJ, Feinstein AG, Robinson VL, May ER, Cole JL. Structural Basis of Protein Kinase R Autophosphorylation. Biochemistry 2019; 58:2967-2977. [PMID: 31246429 DOI: 10.1021/acs.biochem.9b00161] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The RNA-activated protein kinase, PKR, is a key mediator of the innate immunity response to viral infection. Viral double-stranded RNAs induce PKR dimerization and autophosphorylation. The PKR kinase domain forms a back-to-back dimer. However, intermolecular ( trans) autophosphorylation is not feasible in this arrangement. We have obtained PKR kinase structures that resolves this dilemma. The kinase protomers interact via the known back-to-back interface as well as a front-to-front interface that is formed by exchange of activation segments. Mutational analysis of the front-to-front interface support a functional role in PKR activation. Molecular dynamics simulations reveal that the activation segment is highly dynamic in the front-to-front dimer and can adopt conformations conducive to phosphoryl transfer. We propose a mechanism where back-to-back dimerization induces a conformational change that activates PKR to phosphorylate a "substrate" kinase docked in a front-to-front geometry. This mechanism may be relevant to related kinases that phosphorylate the eukaryotic initiation factor eIF2α.
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32
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Colombano G, Caldwell JJ, Matthews TP, Bhatia C, Joshi A, McHardy T, Mok NY, Newbatt Y, Pickard L, Strover J, Hedayat S, Walton MI, Myers SM, Jones AM, Saville H, McAndrew C, Burke R, Eccles SA, Davies FE, Bayliss R, Collins I. Binding to an Unusual Inactive Kinase Conformation by Highly Selective Inhibitors of Inositol-Requiring Enzyme 1α Kinase-Endoribonuclease. J Med Chem 2019; 62:2447-2465. [PMID: 30779566 PMCID: PMC6437697 DOI: 10.1021/acs.jmedchem.8b01721] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2018] [Indexed: 12/19/2022]
Abstract
A series of imidazo[1,2- b]pyridazin-8-amine kinase inhibitors were discovered to allosterically inhibit the endoribonuclease function of the dual kinase-endoribonuclease inositol-requiring enzyme 1α (IRE1α), a key component of the unfolded protein response in mammalian cells and a potential drug target in multiple human diseases. Inhibitor optimization gave compounds with high kinome selectivity that prevented endoplasmic reticulum stress-induced IRE1α oligomerization and phosphorylation, and inhibited endoribonuclease activity in human cells. X-ray crystallography showed the inhibitors to bind to a previously unreported and unusually disordered conformation of the IRE1α kinase domain that would be incompatible with back-to-back dimerization of the IRE1α protein and activation of the endoribonuclease function. These findings increase the repertoire of known IRE1α protein conformations and can guide the discovery of highly selective ligands for the IRE1α kinase site that allosterically inhibit the endoribonuclease.
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Affiliation(s)
- Giampiero Colombano
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - John J. Caldwell
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Thomas P. Matthews
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Chitra Bhatia
- Department
of Molecular and Cell Biology, University
of Leicester, Leicester LE1 7RH, U.K.
| | - Amar Joshi
- Department
of Molecular and Cell Biology, University
of Leicester, Leicester LE1 7RH, U.K.
| | - Tatiana McHardy
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Ngai Yi Mok
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Yvette Newbatt
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Lisa Pickard
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Jade Strover
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Somaieh Hedayat
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Michael I. Walton
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Stephanie M. Myers
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Alan M. Jones
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Harry Saville
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Craig McAndrew
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Rosemary Burke
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Suzanne A. Eccles
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Faith E. Davies
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
| | - Richard Bayliss
- Department
of Molecular and Cell Biology, University
of Leicester, Leicester LE1 7RH, U.K.
- School
of Molecular and Cellular Biology, Faculty of Biological Sciences, University of Leeds, Leeds LS2 9JT, U.K.
| | - Ian Collins
- Cancer
Research UK Cancer Therapeutics Unit and Division of Molecular Pathology, The Institute of Cancer Research, London SW7 3RP, U.K.
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33
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Adams CJ, Kopp MC, Larburu N, Nowak PR, Ali MMU. Structure and Molecular Mechanism of ER Stress Signaling by the Unfolded Protein Response Signal Activator IRE1. Front Mol Biosci 2019; 6:11. [PMID: 30931312 PMCID: PMC6423427 DOI: 10.3389/fmolb.2019.00011] [Citation(s) in RCA: 328] [Impact Index Per Article: 65.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 02/15/2019] [Indexed: 01/03/2023] Open
Abstract
The endoplasmic reticulum (ER) is an important site for protein folding and maturation in eukaryotes. The cellular requirement to synthesize proteins within the ER is matched by its folding capacity. However, the physiological demands or aberrations in folding may result in an imbalance which can lead to the accumulation of misfolded protein, also known as "ER stress." The unfolded protein response (UPR) is a cell-signaling system that readjusts ER folding capacity to restore protein homeostasis. The key UPR signal activator, IRE1, responds to stress by propagating the UPR signal from the ER to the cytosol. Here, we discuss the structural and molecular basis of IRE1 stress signaling, with particular focus on novel mechanistic advances. We draw a comparison between the recently proposed allosteric model for UPR induction and the role of Hsp70 during polypeptide import to the mitochondrial matrix.
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Affiliation(s)
| | | | | | | | - Maruf M. U. Ali
- Department of Life Sciences, Imperial College London, London, United Kingdom
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34
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Carlesso A, Chintha C, Gorman AM, Samali A, Eriksson LA. Binding Analysis of the Inositol-Requiring Enzyme 1 Kinase Domain. ACS OMEGA 2018; 3:13313-13322. [PMID: 30411035 PMCID: PMC6217623 DOI: 10.1021/acsomega.8b01404] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2018] [Accepted: 10/02/2018] [Indexed: 06/08/2023]
Abstract
Inositol-requiring enzyme 1 (IRE1) is an orchestrator of the unfolded protein response (UPR), the cellular response to endoplasmic reticulum (ER) stress that plays a crucial role in tumor development. IRE1 signaling is the most evolutionary conserved branch of the UPR. Under ER stress, the IRE1 luminal domain undergoes a conformational change to multimerize, resulting in trans-autophosphorylation and activation of the cytosolic kinase and endoribonuclease domain. Adenosine triphosphate-competitive inhibitors that bind to the IRE1 kinase site can modulate the activity of the RNase domain through an allosteric relationship between the IRE1 kinase and RNase domains. The current study aims at the investigation of available structural data of the IRE1 kinase domain and provides insights into the design of novel kinase inhibitors. To this end, a detailed analysis of IRE1 kinase active site and investigation of suitable structures for virtual screening studies were performed. The results indicate in silico target fishing as an appropriate strategy for the identification of novel IRE1 kinase binders, further validating the robustness of the in silico protocol. Importantly, the study highlights the kinase-inhibiting RNase attenuator (KIRA)-bound protein data bank 4U6R structure as the best protein structure to perform virtual screening to develop diverse and more potent KIRA-like IRE1 kinase inhibitors that are capable of allosterically affecting the RNase activity.
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Affiliation(s)
- Antonio Carlesso
- Department
of Chemistry and Molecular Biology, University
of Gothenburg, 405 30 Göteborg, Sweden
| | - Chetan Chintha
- Apoptosis
Research Centre, National University of
Ireland Galway, H91 TK33 Galway, Ireland
| | - Adrienne M. Gorman
- Apoptosis
Research Centre, National University of
Ireland Galway, H91 TK33 Galway, Ireland
| | - Afshin Samali
- Apoptosis
Research Centre, National University of
Ireland Galway, H91 TK33 Galway, Ireland
| | - Leif A. Eriksson
- Department
of Chemistry and Molecular Biology, University
of Gothenburg, 405 30 Göteborg, Sweden
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35
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Abdullah A, Ravanan P. The unknown face of IRE1α - Beyond ER stress. Eur J Cell Biol 2018; 97:359-368. [PMID: 29747876 DOI: 10.1016/j.ejcb.2018.05.002] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 05/03/2018] [Accepted: 05/03/2018] [Indexed: 12/16/2022] Open
Abstract
IRE1α (Inositol Requiring kinase Enzyme 1 alpha), a transmembrane protein localized to the endoplasmic reticulum (ER) is a master regulator of the unfolded protein response (UPR) pathway. The fate determining steps during ER stress-induced apoptosis are greatly attributed to IRE1α's endoribonuclease and kinase activities. Apart from its role as a chief executioner in ER stress, recent studies have shown that upon activation in the presence or absence of ER stress, IRE1α executes multiple cellular processes such as differentiation, immune response, progression and repression of the cell cycle. Besides its crucial role in protein misfolding, the versatile contributions of IRE1α in other cellular functions are greatly unknown. In this review, we have discussed the structural conservation of IRE1 among eukaryotes, the mechanisms underlying its activation and the recent understandings of the non-apoptotic functions of IRE1 other than ER stress-induced cell death.
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Affiliation(s)
- Ahmad Abdullah
- Apoptosis and Cell Survival Research Lab, Department of Biosciences, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India
| | - Palaniyandi Ravanan
- Apoptosis and Cell Survival Research Lab, Department of Biosciences, School of Biosciences and Technology, VIT University, Vellore, Tamil Nadu, India.
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36
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Hughes D, Mallucci GR. The unfolded protein response in neurodegenerative disorders - therapeutic modulation of the PERK pathway. FEBS J 2018; 286:342-355. [PMID: 29476642 DOI: 10.1111/febs.14422] [Citation(s) in RCA: 118] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Revised: 01/25/2018] [Accepted: 02/20/2018] [Indexed: 12/22/2022]
Abstract
The unfolded protein response (UPR) is a highly conserved protein quality control mechanism, activated in response to Endoplasmic Reticulum (ER) stress. Signalling is mediated through three branches, PERK, IRE1, and ATF6, respectively, that together provide a coordinated response that contributes to overcoming disrupted proteostasis. PERK branch activation predominantly causes a rapid reduction in global rates of translation, while the IRE1 and ATF6 branch signalling induce a transcriptional response resulting in expression of chaperones and components of the protein degradation machinery. Protein misfolding neurodegenerative diseases show disruption of proteostasis as a biochemical feature. In the brains of animal models of disease and in human post mortem tissue from many of these disorders, markers of UPR induction, particularly, the PERK pathway can be observed in close association with disease progression. Recent research has revealed dysregulated UPR signalling to be a major pathogenic mechanism in neurodegeneration, and that genetic and pharmacological modulation of the PERK pathway results in potent neuroprotection. Targeting aberrant UPR signalling is the focus of new therapeutic strategies, which importantly could be beneficial across the broad spectrum of neurodegenerative diseases.
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Affiliation(s)
| | - Giovanna R Mallucci
- MRC Toxicology Unit, Leicester, UK.,Department of Clinical Neurosciences, University of Cambridge, UK.,UK Dementia Research Institute, University of Cambridge, UK
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37
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Chalmers F, van Lith M, Sweeney B, Cain K, Bulleid NJ. Inhibition of IRE1α-mediated XBP1 mRNA cleavage by XBP1 reveals a novel regulatory process during the unfolded protein response. Wellcome Open Res 2017; 2:36. [PMID: 29062910 PMCID: PMC5645705 DOI: 10.12688/wellcomeopenres.11764.2] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/18/2017] [Indexed: 01/23/2023] Open
Abstract
Background: The mammalian endoplasmic reticulum (ER) continuously adapts to the cellular secretory load by the activation of an unfolded protein response (UPR). This stress response results in expansion of the ER, upregulation of proteins involved in protein folding and degradation, and attenuation of protein synthesis. The response is orchestrated by three signalling pathways each activated by a specific signal transducer, either inositol requiring enzyme α (IRE1α), double-stranded RNA-activated protein kinase-like ER kinase (PERK) or activating transcription factor 6 (ATF6). Activation of IRE1α results in its oligomerisation, autophosphorylation and stimulation of its ribonuclease activity. The ribonuclease initiates the splicing of an intron from mRNA encoding the transcription factor, X-box binding protein 1 (XBP1), as well as degradation of specific mRNAs and microRNAs. Methods: To investigate the consequence of expression of exogenous XBP1, we generated a stable cell-line expressing spliced XBP1 mRNA under the control of an inducible promotor. Results: Following induction of expression, high levels of XBP1 protein were detected, which allowed upregulation of target genes in the absence of induction of the UPR. Remarkably under stress conditions, the expression of exogenous XBP1 repressed splicing of endogenous XBP1 mRNA without repressing the activation of PERK. Conclusions: These results illustrate that a feedback mechanism exists to attenuate Ire1α ribonuclease activity in the presence of XBP1.
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Affiliation(s)
- Fiona Chalmers
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marcel van Lith
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | | | | | - Neil J Bulleid
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
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38
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Chalmers F, van Lith M, Sweeney B, Cain K, Bulleid NJ. Inhibition of IRE1α-mediated XBP1 mRNA cleavage by XBP1 reveals a novel regulatory process during the unfolded protein response. Wellcome Open Res 2017. [PMID: 29062910 DOI: 10.12688/wellcomeopenres.11764.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Background: The mammalian endoplasmic reticulum (ER) continuously adapts to the cellular secretory load by the activation of an unfolded protein response (UPR). This stress response results in expansion of the ER, upregulation of proteins involved in protein folding and degradation, and attenuation of protein synthesis. The response is orchestrated by three signalling pathways each activated by a specific signal transducer, either inositol requiring enzyme α (IRE1α), double-stranded RNA-activated protein kinase-like ER kinase (PERK) or activating transcription factor 6 (ATF6). Activation of IRE1α results in its oligomerisation, autophosphorylation and stimulation of its ribonuclease activity. The ribonuclease initiates the splicing of an intron from mRNA encoding the transcription factor, X-box binding protein 1 (XBP1), as well as degradation of specific mRNAs and microRNAs. Methods: To investigate the consequence of expression of exogenous XBP1, we generated a stable cell-line expressing spliced XBP1 mRNA under the control of an inducible promotor. Results: Following induction of expression, high levels of XBP1 protein were detected, which allowed upregulation of target genes in the absence of induction of the UPR. Remarkably under stress conditions, the expression of exogenous XBP1 repressed splicing of endogenous XBP1 mRNA without repressing the activation of PERK. Conclusions: These results illustrate that a feedback mechanism exists to attenuate Ire1α ribonuclease activity in the presence of XBP1.
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Affiliation(s)
- Fiona Chalmers
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | - Marcel van Lith
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
| | | | | | - Neil J Bulleid
- Institute of Molecular, Cellular and Systems Biology, University of Glasgow, Glasgow, G12 8QQ, UK
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39
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George Z, Omosun Y, Azenabor AA, Partin J, Joseph K, Ellerson D, He Q, Eko F, Bandea C, Svoboda P, Pohl J, Black CM, Igietseme JU. The Roles of Unfolded Protein Response Pathways in Chlamydia Pathogenesis. J Infect Dis 2017; 215:456-465. [PMID: 27932618 DOI: 10.1093/infdis/jiw569] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Indexed: 11/13/2022] Open
Abstract
Chlamydia is an obligate intracellular bacterium that relies on host cells for essential nutrients and adenosine triphosphate (ATP) for a productive infection. Although the unfolded protein response (UPR) plays a major role in certain microbial infectivity, its role in chlamydial pathogenesis is unknown. We hypothesized that Chlamydia induces UPR and exploits it to upregulate host cell uptake and metabolism of glucose, production of ATP, phospholipids, and other molecules required for its replicative development and host survival. Using a combination of biochemical and pathway inhibition assays, we showed that the 3 UPR pathway transducers-protein kinase RNA-activated (PKR)-like ER kinase (PERK), inositol-requiring enzyme-1α (IRE1α), and activating transcription factor-6α (ATF6α)-were activated during Chlamydia infection. The kinase activity of PERK and ribonuclease (RNase) of IRE1α mediated the upregulation of hexokinase II and production of ATP via substrate-level phosphorylation. In addition, the activation of PERK and IRE1α promoted autophagy formation and apoptosis resistance for host survival. Moreover, the activation of IRE1α resulted in the generation of spliced X-box binding protein 1 (sXBP1) and upregulation of lipid production. The vital role of UPR pathways in Chlamydia development and pathogenesis could lead to the identification of potential molecular targets for therapeutics against Chlamydia.
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Affiliation(s)
| | - Yusuf Omosun
- Centers for Disease Control and Prevention, and.,Department of Microbiology, Biochemistry, and Immunology, Morehouse School of Medicine, Atlanta, Georgia
| | | | | | | | | | - Qing He
- Centers for Disease Control and Prevention, and.,Department of Microbiology, Biochemistry, and Immunology, Morehouse School of Medicine, Atlanta, Georgia
| | - Francis Eko
- Department of Microbiology, Biochemistry, and Immunology, Morehouse School of Medicine, Atlanta, Georgia
| | | | | | - Jan Pohl
- Centers for Disease Control and Prevention, and
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40
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Doultsinos D, Avril T, Lhomond S, Dejeans N, Guédat P, Chevet E. Control of the Unfolded Protein Response in Health and Disease. SLAS DISCOVERY 2017; 22:787-800. [PMID: 28453376 DOI: 10.1177/2472555217701685] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The unfolded protein response (UPR) is an integrated, adaptive biochemical process that is inextricably linked with cell homeostasis and paramount to maintenance of normal physiological function. Prolonged accumulation of improperly folded proteins in the endoplasmic reticulum (ER) leads to stress. This is the driving stimulus behind the UPR. As such, prolonged ER stress can push the UPR past beneficial functions such as reduced protein production and increased folding and clearance to apoptotic signaling. The UPR is thus contributory to the commencement, maintenance, and exacerbation of a multitude of disease states, making it an attractive global target to tackle conditions sorely in need of novel therapeutic intervention. The accumulation of information of screening tools, readily available therapies, and potential pathways to drug development is the cornerstone of informed clinical research and clinical trial design. Here, we review the UPR's involvement in health and disease and, beyond providing an in-depth description of the molecules found to target the three UPR arms, we compile all the tools available to screen for and develop novel therapeutic agents that modulate the UPR with the scope of future disease intervention.
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Affiliation(s)
- Dimitrios Doultsinos
- 1 Inserm U1242, Chemistry, Oncogenesis, Stress & Signaling, University of Rennes 1, Rennes, France.,2 Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | - Tony Avril
- 1 Inserm U1242, Chemistry, Oncogenesis, Stress & Signaling, University of Rennes 1, Rennes, France.,2 Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France
| | | | | | | | - Eric Chevet
- 1 Inserm U1242, Chemistry, Oncogenesis, Stress & Signaling, University of Rennes 1, Rennes, France.,2 Centre de Lutte contre le Cancer Eugène Marquis, Rennes, France.,3 BMYscreen, Bergonié Cancer Institute, Bordeaux, France
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41
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Boß M, Newbatt Y, Gupta S, Collins I, Brüne B, Namgaladze D. AMPK-independent inhibition of human macrophage ER stress response by AICAR. Sci Rep 2016; 6:32111. [PMID: 27562249 PMCID: PMC4999824 DOI: 10.1038/srep32111] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 08/02/2016] [Indexed: 12/26/2022] Open
Abstract
Obesity-associated insulin resistance is driven by inflammatory processes in response to metabolic overload. Obesity-associated inflammation can be recapitulated in cell culture by exposing macrophages to saturated fatty acids (SFA), and endoplasmic reticulum (ER) stress responses essentially contribute to pro-inflammatory signalling. AMP-activated protein kinase (AMPK) is a central metabolic regulator with established anti-inflammatory actions. Whether pharmacological AMPK activation suppresses SFA-induced inflammation in a human system is unclear. In a setting of hypoxia-potentiated inflammation induced by SFA palmitate, we found that the AMP-mimetic AMPK activator 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) potently suppressed upregulation of ER stress marker mRNAs and pro-inflammatory cytokines. Furthermore, AICAR inhibited macrophage ER stress responses triggered by ER-stressors thapsigargin or tunicamycin. Surprisingly, AICAR acted independent of AMPK or AICAR conversion to 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranosyl monophosphate (ZMP) while requiring intracellular uptake via the equilibrative nucleoside transporter (ENT) ENT1 or the concentrative nucleoside transporter (CNT) CNT3. AICAR did not affect the initiation of the ER stress response, but inhibited the expression of major ER stress transcriptional effectors. Furthermore, AICAR inhibited autophosphorylation of the ER stress sensor inositol-requiring enzyme 1α (IRE1α), while activating its endoribonuclease activity in vitro. Our results suggest that AMPK-independent inhibition of ER stress responses contributes to anti-inflammatory and anti-diabetic effects of AICAR.
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Affiliation(s)
- Marcel Boß
- Institute of Biochemistry I, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60596 Frankfurt, Germany
| | - Yvette Newbatt
- Division of Cancer Therapeutics, Institute of Cancer Research, Sutton, Surrey SM2 5NG, UK
| | - Sahil Gupta
- Institute of Biochemistry I, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60596 Frankfurt, Germany
| | - Ian Collins
- Division of Cancer Therapeutics, Institute of Cancer Research, Sutton, Surrey SM2 5NG, UK
| | - Bernhard Brüne
- Institute of Biochemistry I, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60596 Frankfurt, Germany.,Project Group Translational Medicine and Pharmacology TMP, Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Theodor-Stern-Kai 7, 60596 Frankfurt, Germany
| | - Dmitry Namgaladze
- Institute of Biochemistry I, Goethe-University Frankfurt, Theodor-Stern-Kai 7, 60596 Frankfurt, Germany
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42
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Feldman HC, Tong M, Wang L, Meza-Acevedo R, Gobillot TA, Lebedev I, Gliedt MJ, Hari SB, Mitra AK, Backes BJ, Papa FR, Seeliger MA, Maly DJ. Structural and Functional Analysis of the Allosteric Inhibition of IRE1α with ATP-Competitive Ligands. ACS Chem Biol 2016; 11:2195-205. [PMID: 27227314 DOI: 10.1021/acschembio.5b00940] [Citation(s) in RCA: 64] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
The accumulation of unfolded proteins under endoplasmic reticulum (ER) stress leads to the activation of the multidomain protein sensor IRE1α as part of the unfolded protein response (UPR). Clustering of IRE1α lumenal domains in the presence of unfolded proteins promotes kinase trans-autophosphorylation in the cytosol and subsequent RNase domain activation. Interestingly, there is an allosteric relationship between the kinase and RNase domains of IRE1α, which allows ATP-competitive inhibitors to modulate the activity of the RNase domain. Here, we use kinase inhibitors to study how ATP-binding site conformation affects the activity of the RNase domain of IRE1α. We find that diverse ATP-competitive inhibitors of IRE1α promote dimerization and activation of RNase activity despite blocking kinase autophosphorylation. In contrast, a subset of ATP-competitive ligands, which we call KIRAs, allosterically inactivate the RNase domain through the kinase domain by stabilizing monomeric IRE1α. Further insight into how ATP-competitive inhibitors are able to divergently modulate the RNase domain through the kinase domain was gained by obtaining the first structure of apo human IRE1α in the RNase active back-to-back dimer conformation. Comparison of this structure with other existing structures of IRE1α and integration of our extensive structure activity relationship (SAR) data has led us to formulate a model to rationalize how ATP-binding site ligands are able to control the IRE1α oligomeric state and subsequent RNase domain activity.
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Affiliation(s)
- Hannah C. Feldman
- Department
of Chemistry, University of Washington, Seattle, Washington, United States
| | - Michael Tong
- Department
of Pharmacological Sciences, Stony Brook University Medical School, Stony
Brook, New York, United States
| | - Likun Wang
- Department
of Medicine, University of California−San Francisco, San Francisco, California, United States
- Diabetes
Center, University of California−San Francisco, San Francisco, California, United States
- Lung
Biology Center, University of California−San Francisco, San Francisco, California, United States
- California
Institute for Quantitative Biosciences, University of California−San Francisco, San Francisco, California, United States
| | - Rosa Meza-Acevedo
- Department
of Medicine, University of California−San Francisco, San Francisco, California, United States
- Diabetes
Center, University of California−San Francisco, San Francisco, California, United States
- Lung
Biology Center, University of California−San Francisco, San Francisco, California, United States
- California
Institute for Quantitative Biosciences, University of California−San Francisco, San Francisco, California, United States
| | - Theodore A. Gobillot
- Department
of Chemistry, University of Washington, Seattle, Washington, United States
| | - Ivan Lebedev
- Department
of Pharmacological Sciences, Stony Brook University Medical School, Stony
Brook, New York, United States
| | - Micah J. Gliedt
- Department
of Medicine, University of California−San Francisco, San Francisco, California, United States
- Lung
Biology Center, University of California−San Francisco, San Francisco, California, United States
| | - Sanjay B. Hari
- Department
of Chemistry, University of Washington, Seattle, Washington, United States
| | - Arinjay K. Mitra
- Department
of Chemistry, University of Washington, Seattle, Washington, United States
| | - Bradley J. Backes
- Department
of Medicine, University of California−San Francisco, San Francisco, California, United States
- Lung
Biology Center, University of California−San Francisco, San Francisco, California, United States
| | - Feroz R. Papa
- Department
of Medicine, University of California−San Francisco, San Francisco, California, United States
- Diabetes
Center, University of California−San Francisco, San Francisco, California, United States
- Lung
Biology Center, University of California−San Francisco, San Francisco, California, United States
- California
Institute for Quantitative Biosciences, University of California−San Francisco, San Francisco, California, United States
| | - Markus A. Seeliger
- Department
of Pharmacological Sciences, Stony Brook University Medical School, Stony
Brook, New York, United States
| | - Dustin J. Maly
- Department
of Chemistry, University of Washington, Seattle, Washington, United States
- Department
of Biochemistry, University of Washington, Seattle, Washington, United States
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43
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Cubillos-Ruiz JR, Bettigole SE, Glimcher LH. Molecular Pathways: Immunosuppressive Roles of IRE1α-XBP1 Signaling in Dendritic Cells of the Tumor Microenvironment. Clin Cancer Res 2016; 22:2121-6. [PMID: 26979393 DOI: 10.1158/1078-0432.ccr-15-1570] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2016] [Accepted: 03/04/2016] [Indexed: 12/11/2022]
Abstract
The endoplasmic reticulum (ER) is a massive cytoplasmic membrane network that functions primarily to ensure proper folding and posttranslational modification of newly synthesized secreted and transmembrane proteins. Abnormal accumulation of unfolded proteins in this organelle causes a state of "ER stress," which is a hallmark feature of various diseases, including cancer, neurodegeneration, and metabolic dysfunction. Cancer cells exploit the IRE1α-XBP1 arm of the ER stress response to efficiently adjust their protein-folding capacity and ensure survival under hostile tumor microenvironmental conditions. However, we recently found that dendritic cells (DC) residing in the ovarian cancer microenvironment also experience sustained ER stress and demonstrate persistent activation of the IRE1α-XBP1 pathway. This previously unrecognized process disrupts metabolic homeostasis and antigen-presenting capacity in DCs, thereby crippling their natural ability to support the protective functions of infiltrating antitumor T cells. In this review, we briefly discuss some of the mechanisms that fuel ER stress in tumor-associated DCs, the biologic processes altered by aberrant IRE1α-XBP1 signaling in these innate immune cells, and the unique immunotherapeutic potential of targeting this pathway in cancer hosts. Clin Cancer Res; 22(9); 2121-6. ©2016 AACR.
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Affiliation(s)
- Juan R Cubillos-Ruiz
- Department of Obstetrics and Gynecology, Weill Cornell Medical College, New York, New York. Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, New York.
| | - Sarah E Bettigole
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, New York. Department of Medicine, Weill Cornell Medical College, New York, New York
| | - Laurie H Glimcher
- Sandra and Edward Meyer Cancer Center, Weill Cornell Medical College, New York, New York. Department of Medicine, Weill Cornell Medical College, New York, New York.
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Mechanistic basis of Nek7 activation through Nek9 binding and induced dimerization. Nat Commun 2015; 6:8771. [PMID: 26522158 PMCID: PMC4632185 DOI: 10.1038/ncomms9771] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 10/01/2015] [Indexed: 01/02/2023] Open
Abstract
Mitotic spindle assembly requires the regulated activities of protein kinases such as Nek7 and Nek9. Nek7 is autoinhibited by the protrusion of Tyr97 into the active site and activated by the Nek9 non-catalytic C-terminal domain (CTD). CTD binding apparently releases autoinhibition because mutation of Tyr97 to phenylalanine increases Nek7 activity independently of Nek9. Here we find that self-association of the Nek9-CTD is needed for Nek7 activation. We map the minimal Nek7 binding region of Nek9 to residues 810-828. A crystal structure of Nek7(Y97F) bound to Nek9(810-828) reveals a binding site on the C-lobe of the Nek7 kinase domain. Nek7(Y97F) crystallizes as a back-to-back dimer between kinase domain N-lobes, in which the specific contacts within the interface are coupled to the conformation of residue 97. Hence, we propose that the Nek9-CTD activates Nek7 through promoting back-to-back dimerization that releases the autoinhibitory tyrosine residue, a mechanism conserved in unrelated kinase families.
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45
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Peschek J, Acosta-Alvear D, Mendez AS, Walter P. A conformational RNA zipper promotes intron ejection during non-conventional XBP1 mRNA splicing. EMBO Rep 2015; 16:1688-98. [PMID: 26483401 PMCID: PMC4687415 DOI: 10.15252/embr.201540955] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Accepted: 09/18/2015] [Indexed: 12/03/2022] Open
Abstract
The kinase/endonuclease IRE1 is the most conserved signal transducer of the unfolded protein response (UPR), an intracellular signaling network that monitors and regulates the protein folding capacity of the endoplasmic reticulum (ER). Upon sensing protein folding perturbations in the ER, IRE1 initiates the unconventional splicing of XBP1 mRNA culminating in the production of the transcription factor XBP1s, which expands the ER's protein folding capacity. We show that an RNA‐intrinsic conformational change causes the intron of XBP1 mRNA to be ejected and the exons to zipper up into an extended stem, juxtaposing the RNA ends for ligation. These conformational rearrangements are important for XBP1 mRNA splicing in vivo. The features that point to such active participation of XBP1 mRNA in the splicing reaction are highly conserved throughout metazoan evolution, supporting their importance in orchestrating XBP1 mRNA processing with efficiency and fidelity.
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Affiliation(s)
- Jirka Peschek
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA
| | - Diego Acosta-Alvear
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA
| | - Aaron S Mendez
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA Department of Cellular and Molecular Pharmacology, University of California San Francisco, San Francisco, CA, USA
| | - Peter Walter
- Department of Biochemistry and Biophysics and Howard Hughes Medical Institute, University of California San Francisco, San Francisco, CA, USA
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46
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Concha NO, Smallwood A, Bonnette W, Totoritis R, Zhang G, Federowicz K, Yang J, Qi H, Chen S, Campobasso N, Choudhry AE, Shuster LE, Evans KA, Ralph J, Sweitzer S, Heerding DA, Buser CA, Su DS, DeYoung MP. Long-Range Inhibitor-Induced Conformational Regulation of Human IRE1α Endoribonuclease Activity. Mol Pharmacol 2015; 88:1011-23. [PMID: 26438213 DOI: 10.1124/mol.115.100917] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 09/25/2015] [Indexed: 12/21/2022] Open
Abstract
Activation of the inositol-requiring enzyme-1 alpha (IRE1α) protein caused by endoplasmic reticulum stress results in the homodimerization of the N-terminal endoplasmic reticulum luminal domains, autophosphorylation of the cytoplasmic kinase domains, and conformational changes to the cytoplasmic endoribonuclease (RNase) domains, which render them functional and can lead to the splicing of X-box binding protein 1 (XBP 1) mRNA. Herein, we report the first crystal structures of the cytoplasmic portion of a human phosphorylated IRE1α dimer in complex with (R)-2-(3,4-dichlorobenzyl)-N-(4-methylbenzyl)-2,7-diazaspiro(4.5)decane-7-carboxamide, a novel, IRE1α-selective kinase inhibitor, and staurosporine, a broad spectrum kinase inhibitor. (R)-2-(3,4-dichlorobenzyl)-N-(4-methylbenzyl)-2,7-diazaspiro(4.5)decane-7-carboxamide inhibits both the kinase and RNase activities of IRE1α. The inhibitor interacts with the catalytic residues Lys599 and Glu612 and displaces the kinase activation loop to the DFG-out conformation. Inactivation of IRE1α RNase activity appears to be caused by a conformational change, whereby the αC helix is displaced, resulting in the rearrangement of the kinase domain-dimer interface and a rotation of the RNase domains away from each other. In contrast, staurosporine binds at the ATP-binding site of IRE1α, resulting in a dimer consistent with RNase active yeast Ire1 dimers. Activation of IRE1α RNase activity appears to be promoted by a network of hydrogen bond interactions between highly conserved residues across the RNase dimer interface that place key catalytic residues poised for reaction. These data implicate that the intermolecular interactions between conserved residues in the RNase domain are required for activity, and that the disruption of these interactions can be achieved pharmacologically by small molecule kinase domain inhibitors.
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Affiliation(s)
- Nestor O Concha
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Angela Smallwood
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - William Bonnette
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Rachel Totoritis
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Guofeng Zhang
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Kelly Federowicz
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Jingsong Yang
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Hongwei Qi
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Stephanie Chen
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Nino Campobasso
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Anthony E Choudhry
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Leanna E Shuster
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Karen A Evans
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Jeff Ralph
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Sharon Sweitzer
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Dirk A Heerding
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Carolyn A Buser
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - Dai-Shi Su
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
| | - M Phillip DeYoung
- Oncology R&D (K.F., J.Y., L.E.S., K.A.E., J.R., D.A.H., C.A.B., D.S.S, M.P.D.), Biological Sciences (R.T., G.Z., H.Q., S.C., A.E.C., S.S.), and Chemical Sciences, GlaxoSmithKline Research and Development, Collegeville, Pennsylvania (N.O.C., A.S., W.B., N.C.)
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