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Amanya SB, Oyewole-Said D, Ernste KJ, Bisht N, Murthy A, Vazquez-Perez J, Konduri V, Decker WK. The mARS complex: a critical mediator of immune regulation and homeostasis. Front Immunol 2024; 15:1423510. [PMID: 38975338 PMCID: PMC11224427 DOI: 10.3389/fimmu.2024.1423510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2024] [Accepted: 06/06/2024] [Indexed: 07/09/2024] Open
Abstract
Over the course of evolution, many proteins have undergone adaptive structural changes to meet the increasing homeostatic regulatory demands of multicellularity. Aminoacyl tRNA synthetases (aaRS), enzymes that catalyze the attachment of each amino acid to its cognate tRNA, are such proteins that have acquired new domains and motifs that enable non-canonical functions. Through these new domains and motifs, aaRS can assemble into large, multi-subunit complexes that enhance the efficiency of many biological functions. Moreover, because the complexity of multi-aminoacyl tRNA synthetase (mARS) complexes increases with the corresponding complexity of higher eukaryotes, a contribution to regulation of homeostatic functions in multicellular organisms is hypothesized. While mARS complexes in lower eukaryotes may enhance efficiency of aminoacylation, little evidence exists to support a similar role in chordates or other higher eukaryotes. Rather, mARS complexes are reported to regulate multiple and variegated cellular processes that include angiogenesis, apoptosis, inflammation, anaphylaxis, and metabolism. Because all such processes are critical components of immune homeostasis, it is important to understand the role of mARS complexes in immune regulation. Here we provide a conceptual analysis of the current understanding of mARS complex dynamics and emerging mARS complex roles in immune regulation, the increased understanding of which should reveal therapeutic targets in immunity and immune-mediated disease.
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Affiliation(s)
- Sharon Bright Amanya
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Damilola Oyewole-Said
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Keenan J. Ernste
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Nalini Bisht
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Arnav Murthy
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
- Department of Natural Sciences, Rice University, Houston, TX, United States
| | - Jonathan Vazquez-Perez
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
| | - Vanaja Konduri
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, United States
| | - William K. Decker
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, United States
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, United States
- Center for Cell and Gene Therapy, Baylor College of Medicine, Houston, TX, United States
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Yuan C, Liu X, Cai S, Zhang L, Guo R, Jia Z, Sun Y, Li B. Secreted aminoacyl-tRNA synthetase-interacting multifunctional protein-1 (AIMP1) is a promising predictor for the severity of acute AQP4-IgG positive neuromyelitis optica spectrum disorder. Mult Scler Relat Disord 2023; 70:104504. [PMID: 36623394 DOI: 10.1016/j.msard.2023.104504] [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: 07/20/2022] [Revised: 10/18/2022] [Accepted: 01/02/2023] [Indexed: 01/06/2023]
Abstract
BACKGROUND AND OBJECTIVES Aminoacyl-tRNA synthetase complex interacting with multifunctional protein-1 (AIMP1) has been reported to carry pro-inflammatory properties and anti-angiogenesis effects. However, the exact role of AIMP1 in patients with NMOSD is not yet clear. Our objective was to investigate the relationship between plasma AIMP1 levels and disease severity in patients with AQP4-IgG+ NMOSD from North China based on the Expanded Disability Status Scale (EDSS) score. METHODS Plasma AIMP1 levels were measured using ELISA kits in 94 patients with AQP4-IgG+NMOSD (48 in the acute phase before high-dose intravenous methylprednisolone (IVMP) therapy, 21 in the acute phase after IVMP therapy, 25 in the clinical remission-phase)as well as 33 healthy controls (HCs). The disability function of NMOSD patients was evaluated using the EDSS score. Furthermore, the clinical characteristics of the patients were also evaluated, and laboratory tests were performed on blood samples. RESULTS The plasma AIMP1 levels in AQP4-IgG+NMOSD patients with acute phase before IVMP therapy were significantly higher as compared to those in patients after the IVMP therapy (p < 0.001) as well as those in the clinical remission phase (p = 0.021) or HCs (p < 0.001). Plasma AIMP1 levels were positively correlated with EDSS scores (r = 0.485, p < 0.001) and negatively correlated with serum complement 3 concentrations (r =-0.452, p = 0.001). AIMP1 exhibited the potential to distinguish NMOSD from HCs (AUROC 0.820, p < 0.0001) and could differentiate mild and moderate-severe NMOSD (AUROC 0.790, p = 0.0006). Furthermore, plasma AIMP1 levels of ≥49.55pg/mL were found to be an independent predictor of the risk for moderate-severe NMOSD (with OR 0.03, 95%CI 0.001-0.654, p = 0.026). CONCLUSION AIMP1 may be involved in the pathogenesis of AQP4-IgG+NMOSD disease and predict the disease activity, severity, or effect of treatment in patients with NMOSD. Further studies should be performed to reveal the precise mechanisms of AQP4-IgG+NMOSD.
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Affiliation(s)
- Congcong Yuan
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China; Department of Neurology, Baoding First Central Hospital, Baoding, China
| | - Xueyu Liu
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Shuang Cai
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Lu Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Ruoyi Guo
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Zhen Jia
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Yafei Sun
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China
| | - Bin Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang, China; The Key Laboratory of Neurology (Hebei Medical University), Ministry of Education, Shijiazhuang, Hebei 050000, China.
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Abstract
Viruses are intracellular parasites that subvert the functions of their host cells to accomplish their infection cycle. The endoplasmic reticulum (ER)-residing chaperone proteins are central for the achievement of different steps of the viral cycle, from entry and replication to assembly and exit. The most abundant ER chaperones are GRP78 (78-kDa glucose-regulated protein), GRP94 (94-kDa glucose-regulated protein), the carbohydrate or lectin-like chaperones calnexin (CNX) and calreticulin (CRT), the protein disulfide isomerases (PDIs), and the DNAJ chaperones. This review will focus on the pleiotropic roles of ER chaperones during viral infection. We will cover their essential role in the folding and quality control of viral proteins, notably viral glycoproteins which play a major role in host cell infection. We will also describe how viruses co-opt ER chaperones at various steps of their infectious cycle but also in order to evade immune responses and avoid apoptosis. Finally, we will discuss the different molecules targeting these chaperones and the perspectives in the development of broad-spectrum antiviral drugs.
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4
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The Pathophysiological Role of Heat Shock Response in Autoimmunity: A Literature Review. Cells 2021; 10:cells10102626. [PMID: 34685607 PMCID: PMC8533860 DOI: 10.3390/cells10102626] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2021] [Revised: 09/27/2021] [Accepted: 09/28/2021] [Indexed: 12/16/2022] Open
Abstract
Within the last two decades, there has been increasing evidence that heat-shock proteins can have a differential influence on the immune system. They can either provoke or ameliorate immune responses. This review focuses on outlining the stimulatory as well as the inhibitory effects of heat-shock proteins 27, 40, 70, 65, 60, and 90 in experimental and clinical autoimmune settings.
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Lee JS, Im CH, Lee SJ, Choi JY, Han JM, Kim S, Kim DJ, Park T, Lee EY, Song YW. Glycoprotein 96 polymorphisms are associated with the risk of systemic lupus erythematosus: A case-control study. Int J Rheum Dis 2019; 22:905-912. [PMID: 30860673 DOI: 10.1111/1756-185x.13515] [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: 07/04/2018] [Revised: 12/22/2018] [Accepted: 01/27/2019] [Indexed: 12/01/2022]
Abstract
AIM To investigate the clinical implications of a genetic polymorphism in glycoprotein 96 (GP96), by analyzing the association between the genotype and haplotype of GP96 with systemic lupus erythematosus (SLE). METHOD We analyzed cell-surface expression of GP96 in peripheral blood mononuclear cells (PBMCs) and serum titer of anti-GP96 antibody of SLE patients. Single nucleotide polymorphisms and deletion mutants of GP96 were detected by two-dimensional gene scanning (TDGS). Odds ratios with 95% confidence intervals (CI) were determined for each genotype and haplotype through the chi-square test. RESULTS In total, 216 Korean SLE patients and 215 age- and sex-matched healthy controls were enrolled. In SLE patients, as opposed to healthy controls, cell-surface expression of GP96 among human leukocyte antigen-DR+ PBMCs (76.4% vs 45.5%, respectively, P < 0.001) and serum anti-GP96 antibody titers (0.98 vs 0.50, respectively, P = 0.012) increased. TDGS revealed six polymorphic sites in GP96, two of which were significantly associated with SLE (exon 1, g.-7C>G, odds ratio [OR] 1.78, 95% CI 1.16-2.75, P = 0.009; exon 17, g.17009_17011del, OR 1.76, 95% CI 1.18-2.64, P = 0.006). Two haplotypes (121111, 211212) were strongly associated with SLE (OR 8.92, 95% CI 1.10-72.6, P = 0.041; OR 3.03, 95% CI 1.22-7.50, P = 0.017, respectively) and specific clinical manifestations (discoid rash, arthritis, renal disorder, neurologic disorder, and hematologic disorder). Haplotype-based analysis revealed a stronger association between GP96 and SLE than did genotype-based analysis. CONCLUSION The two polymorphisms, each in exons 1 and 17 of GP96 are potential genetic risk factors of SLE. Two haplotypes 121111 and 211212 are related to not only SLE but also specific clinical manifestations.
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Affiliation(s)
- Jeong Seok Lee
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Churl Hyun Im
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Sang Jin Lee
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Ji Yong Choi
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Jung Min Han
- College of Pharmacy, Yonsei University, Incheon, Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Dong Jo Kim
- Biotechnology 2 Institute, Celltrion Inc., Incheon, Korea
| | - Taesung Park
- Department of Statistics, Seoul National University, Seoul, Korea
| | - Eun Young Lee
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Yeong Wook Song
- Division of Rheumatology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea
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6
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Kim SB, Kim HR, Park MC, Cho S, Goughnour PC, Han D, Yoon I, Kim Y, Kang T, Song E, Kim P, Choi H, Mun JY, Song C, Lee S, Jung HS, Kim S. Caspase-8 controls the secretion of inflammatory lysyl-tRNA synthetase in exosomes from cancer cells. J Cell Biol 2017; 216:2201-2216. [PMID: 28611052 PMCID: PMC5496609 DOI: 10.1083/jcb.201605118] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 10/05/2016] [Accepted: 05/04/2017] [Indexed: 12/20/2022] Open
Abstract
Aminoacyl-tRNA synthetases (ARSs), enzymes that normally control protein synthesis, can be secreted and have different activities in the extracellular space, but the mechanism of their secretion is not understood. This study describes the secretion route of the ARS lysyl-tRNA synthetase (KRS) and how this process is regulated by caspase activity, which has been implicated in the unconventional secretion of other proteins. We show that KRS is secreted from colorectal carcinoma cells within the lumen of exosomes that can trigger an inflammatory response. Caspase-8 cleaved the N-terminal of KRS, thus exposing a PDZ-binding motif located in the C terminus of KRS. Syntenin bound to the exposed PDZ-binding motif of KRS and facilitated the exosomic secretion of KRS dissociated from the multi-tRNA synthetase complex. KRS-containing exosomes released by cancer cells induced macrophage migration, and their secretion of TNF-α and cleaved KRS made a significant contribution to these activities, which suggests a novel mechanism by which caspase-8 may promote inflammation.
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Affiliation(s)
- Sang Bum Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
| | - Hye Rim Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea
| | - Min Chul Park
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea
| | - Seongmin Cho
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
| | - Peter C Goughnour
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
| | - Daeyoung Han
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
| | - Ina Yoon
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea
| | - YounHa Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea.,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
| | - Taehee Kang
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea
| | - Eunjoo Song
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Pilhan Kim
- Graduate School of Nanoscience and Technology, Korea Advanced Institute of Science and Technology, Daejeon, South Korea
| | - Hyosun Choi
- BK21 Plus Program, Department of Senior Healthcare, Graduate School, Eulji University, Daejeon, South Korea
| | - Ji Young Mun
- BK21 Plus Program, Department of Senior Healthcare, Graduate School, Eulji University, Daejeon, South Korea.,Department of Biomedical Laboratory Science, College of Health Sciences, Eulji University, Seongnam, South Korea
| | - Chihong Song
- National Institute for Physiological Sciences, Okazaki, Japan
| | - Sangmin Lee
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, South Korea
| | - Hyun Suk Jung
- Department of Biochemistry, College of Natural Sciences, Kangwon National University, Chuncheon, South Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Suwon, South Korea .,Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, South Korea
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Khachatoorian R, French SW. Chaperones in hepatitis C virus infection. World J Hepatol 2016; 8:9-35. [PMID: 26783419 PMCID: PMC4705456 DOI: 10.4254/wjh.v8.i1.9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 10/01/2015] [Accepted: 12/18/2015] [Indexed: 02/06/2023] Open
Abstract
The hepatitis C virus (HCV) infects approximately 3% of the world population or more than 185 million people worldwide. Each year, an estimated 350000-500000 deaths occur worldwide due to HCV-associated diseases including cirrhosis and hepatocellular carcinoma. HCV is the most common indication for liver transplantation in patients with cirrhosis worldwide. HCV is an enveloped RNA virus classified in the genus Hepacivirus in the Flaviviridae family. The HCV viral life cycle in a cell can be divided into six phases: (1) binding and internalization; (2) cytoplasmic release and uncoating; (3) viral polyprotein translation and processing; (4) RNA genome replication; (5) encapsidation (packaging) and assembly; and (6) virus morphogenesis (maturation) and secretion. Many host factors are involved in the HCV life cycle. Chaperones are an important group of host cytoprotective molecules that coordinate numerous cellular processes including protein folding, multimeric protein assembly, protein trafficking, and protein degradation. All phases of the viral life cycle require chaperone activity and the interaction of viral proteins with chaperones. This review will present our current knowledge and understanding of the role of chaperones in the HCV life cycle. Analysis of chaperones in HCV infection will provide further insights into viral/host interactions and potential therapeutic targets for both HCV and other viruses.
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8
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Liang D, Halpert MM, Konduri V, Decker WK. Stepping Out of the Cytosol: AIMp1/p43 Potentiates the Link Between Innate and Adaptive Immunity. Int Rev Immunol 2015; 34:367-81. [DOI: 10.3109/08830185.2015.1077829] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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9
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Plasma membrane gp96 enhances invasion and metastatic potential of liver cancer via regulation of uPAR. Mol Oncol 2015; 9:1312-23. [PMID: 25841765 DOI: 10.1016/j.molonc.2015.03.004] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Revised: 03/13/2015] [Accepted: 03/14/2015] [Indexed: 12/28/2022] Open
Abstract
Targeted therapy is currently under intensive investigation due to the resistance of liver cancer to cytotoxic chemotherapies. Dissecting the molecular events that drive the progression of liver cancer and defining specific targets are urgently needed to develop efficient tailored therapies. Cell membrane gp96 (mgp96) has been implicated in tumor growth and malignancy. Here, we explored the functional and clinical relevance of mgp96 in liver cancer. We found that elevated mgp96 abundance was associated with tumor metastasis and recurrence in patients with primary liver tumors. Decreased KDELR1 levels in hepatoma cells contribute to cell membrane translocation of the normally ER-resident gp96. Urokinase-type plasminogen activator receptor (uPAR) was identified as a mgp96 client protein, and mgp96 stabilized uPAR protein. Our clinical results proved that elevated mgp96 abundance is positively correlated with uPAR expression levels in liver tumors. We further provided evidence that targeting mgp96 with siRNA or a specific mAb that blocked the mgp96-uPAR interaction led to inhibited cell growth, survival, and invasion in vitro, as well as the suppression of liver tumor growth and metastasis in vivo. mgp96 promotes liver cancer progression through increasing the protein stability and signaling of uPAR, and may be a new promising target for suppressing uPAR-mediated tumor growth and metastasis in liver cancer.
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10
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Xu H, Malinin NL, Awasthi N, Schwarz RE, Schwarz MA. The N terminus of pro-endothelial monocyte-activating polypeptide II (EMAP II) regulates its binding with the C terminus, arginyl-tRNA synthetase, and neurofilament light protein. J Biol Chem 2015; 290:9753-66. [PMID: 25724651 DOI: 10.1074/jbc.m114.630533] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2014] [Indexed: 12/17/2022] Open
Abstract
Pro-endothelial monocyte-activating polypeptide II (EMAP II), one component of the multi-aminoacyl tRNA synthetase complex, plays multiple roles in physiological and pathological processes of protein translation, signal transduction, immunity, lung development, and tumor growth. Recent studies have determined that pro-EMAP II has an essential role in maintaining axon integrity in central and peripheral neural systems where deletion of the C terminus of pro-EMAP II has been reported in a consanguineous Israeli Bedouin kindred suffering from Pelizaeus-Merzbacher-like disease. We hypothesized that the N terminus of pro-EMAP II has an important role in the regulation of protein-protein interactions. Using a GFP reporter system, we defined a putative leucine zipper in the N terminus of human pro-EMAP II protein (amino acid residues 1-70) that can form specific strip-like punctate structures. Through GFP punctum analysis, we uncovered that the pro-EMAP II C terminus (amino acids 147-312) can repress GFP punctum formation. Pulldown assays confirmed that the binding between the pro-EMAP II N terminus and its C terminus is mediated by a putative leucine zipper. Furthermore, the pro-EMAP II 1-70 amino acid region was identified as the binding partner of arginyl-tRNA synthetase, a polypeptide of the multi-aminoacyl tRNA synthetase complex. We also determined that the punctate GFP pro-EMAP II 1-70 amino acid aggregate colocalizes and binds to the neurofilament light subunit protein that is associated with pathologic neurofilament network disorganization and degeneration of motor neurons. These findings indicate the structure and binding interaction of pro-EMAP II protein and suggest a role of this protein in pathological neurodegenerative diseases.
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Affiliation(s)
- Haiming Xu
- From the Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390 and
| | - Nikolay L Malinin
- the Indiana University School of Medicine, South Bend, Indiana 46617
| | - Niranjan Awasthi
- the Indiana University School of Medicine, South Bend, Indiana 46617
| | | | - Margaret A Schwarz
- From the Department of Pediatrics, University of Texas Southwestern Medical Center at Dallas, Dallas, Texas 75390 and the Indiana University School of Medicine, South Bend, Indiana 46617
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11
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Wiersma VR, Michalak M, Abdullah TM, Bremer E, Eggleton P. Mechanisms of Translocation of ER Chaperones to the Cell Surface and Immunomodulatory Roles in Cancer and Autoimmunity. Front Oncol 2015; 5:7. [PMID: 25688334 PMCID: PMC4310273 DOI: 10.3389/fonc.2015.00007] [Citation(s) in RCA: 100] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 01/10/2015] [Indexed: 01/12/2023] Open
Abstract
Endoplasmic reticulum (ER) chaperones (e.g., calreticulin, heat shock proteins, and isomerases) perform a multitude of functions within the ER. However, many of these chaperones can translocate to the cytosol and eventually the surface of cells, particularly during ER stress induced by e.g., drugs, UV irradiation, and microbial stimuli. Once on the cell surface or in the extracellular space, the ER chaperones can take on immunogenic characteristics, as mostly described in the context of cancer, appearing as damage-associated molecular patterns recognized by the immune system. How ER chaperones relocate to the cell surface and interact with other intracellular proteins appears to influence whether a tumor cell is targeted for cell death. The relocation of ER proteins to the cell surface can be exploited to target cancer cells for elimination by immune mechanism. Here we evaluate the evidence for the different mechanisms of ER protein translocation and binding to the cell surface and how ER protein translocation can act as a signal for cancer cells to undergo killing by immunogenic cell death and other cell death pathways. The release of chaperones can also exacerbate underlying autoimmune conditions, such as rheumatoid arthritis and multiple sclerosis, and the immunomodulatory role of extracellular chaperones as potential cancer immunotherapies requires cautious monitoring, particularly in cancer patients with underlying autoimmune disease.
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Affiliation(s)
- Valerie R. Wiersma
- Department of Surgery, Translational Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Marek Michalak
- University of Exeter Medical School, Exeter Devon, UK
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
| | | | - Edwin Bremer
- Department of Surgery, Translational Surgical Oncology, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
- University of Exeter Medical School, Exeter Devon, UK
| | - Paul Eggleton
- University of Exeter Medical School, Exeter Devon, UK
- Department of Biochemistry, University of Alberta, Edmonton, AB, Canada
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12
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Jeong JH, Park M, Park M, Lim EJ, Kim HR, Song H, Park SG, Choi EJ, Hong KH, Lee DR, Ko JJ, Choi Y. The expression of aminoacyl-tRNA-synthetase-interacting multifunctional protein-1 (Aimp1) is regulated by estrogen in the mouse uterus. Mol Cell Endocrinol 2015; 399:78-86. [PMID: 25132647 DOI: 10.1016/j.mce.2014.07.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 06/18/2014] [Accepted: 07/11/2014] [Indexed: 11/20/2022]
Abstract
Aimp1 is known as a multifunctional cytokine in various cellular events. Recent study showed Aimp1 is localized in glandular epithelial, endothelial, and stromal cells in functionalis and basalis layers of the endometrium. However, the regulatory mechanism of Aimp1 in the uterus remains unknown. In the present study, we found that Aimp1 is expressed in the mouse uterus. Aimp1 transcripts were decreased at diestrus stage. However, the level of Aimp1 protein was significantly increased in the luminal epithelium in the uterine endometrium at estrus stage during the estrous cycle. We found that treatment of estrogen increased the expression of Aimp1 in the uterus in ovarectomized mice. We identified one estrogen receptor binding element (ERE) on mouse Aimp1 promoter. The activity of Aimp1 promoter was increased with estrogen treatment. Our findings indicate that Aimp1 might act as an important regulator to remodel the uterine endometrium and its expression might be regulated by estrogen during the estrous cycle. This will give us better understanding of the dynamic change of uterine remodeling during the estrous cycle.
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Affiliation(s)
- Ji-Hye Jeong
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Miree Park
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Miseon Park
- Fertility Center of CHA Gangnam Medical Center, Seoul 135-081, Korea
| | - Eun Jin Lim
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Hye-Ryun Kim
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Haengseok Song
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Sang Gyu Park
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Eun-Jin Choi
- Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Korea
| | - Kwon-Ho Hong
- Department of Nanobiomedical Science & BK21 PLUS NBM Global Research Center for Regenerative Medicine, Dankook University, Cheonan 330-714, Korea
| | - Dong Ryul Lee
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea; Fertility Center of CHA Gangnam Medical Center, Seoul 135-081, Korea
| | - Jeong-Jae Ko
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea
| | - Youngsok Choi
- Department of Biomedical Science, College of Medicine CHA University, Seoul 135-081, Korea; Fertility Center of CHA Gangnam Medical Center, Seoul 135-081, Korea.
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Kim MS, Kim S, Myung H. Degradation of AIMP1/p43 induced by hepatitis C virus E2 leads to upregulation of TGF-β signaling and increase in surface expression of gp96. PLoS One 2014; 9:e96302. [PMID: 24816397 PMCID: PMC4015952 DOI: 10.1371/journal.pone.0096302] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Accepted: 04/05/2014] [Indexed: 12/25/2022] Open
Abstract
Hepatitis C virus (HCV) causes chronic hepatitis leading to liver fibrosis and autoimmune diseases. AIMP1/p43 is a multifunctional protein initially known as a cofactor of aminoacyl tRNA synthetase complex. Its function includes negative regulation of TGF-β signaling and suppression of Lupus-like autoimmune disease by inhibition of surface expression of gp96. HCV E2 was shown to directly interact with AIMP1/p43 by GST pulldown assay and coimmunoprecipitation. Their subcellular colocalization was observed in an immunofluorescence confocal microscopy. We showed that HCV E2 led to degradation of AIMP1/p43 in two ways. First, in the presence of HCV E2, endogenous AIMP1/p43 was shown to be degraded in an ubiquitin-dependent proteasome pathway. Second, grp78, an ER chaperone, was shown to interact with and stabilize AIMP1/p43. And HCV E2 inhibited this interaction leading to reduction of cellular AIMP1/p43. The degradation of AIMP1/p43 by HCV E2 resulted in increase of TGF-β signaling and cell surface expression of gp96. Thus we suggest that these are novel mechanisms responsible for liver fibrosis and autoimmune diseases caused by HCV.
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Affiliation(s)
- Min Soo Kim
- Department of Bioscience and Biotechnology, Hankuk University of Foreign Studies, Yong-In, Gyung-Gi Do, Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Heejoon Myung
- Department of Bioscience and Biotechnology, Hankuk University of Foreign Studies, Yong-In, Gyung-Gi Do, Korea
- * E-mail:
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Pang YLJ, Poruri K, Martinis SA. tRNA synthetase: tRNA aminoacylation and beyond. WILEY INTERDISCIPLINARY REVIEWS-RNA 2014; 5:461-80. [PMID: 24706556 DOI: 10.1002/wrna.1224] [Citation(s) in RCA: 103] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2010] [Revised: 01/14/2014] [Accepted: 02/06/2014] [Indexed: 01/20/2023]
Abstract
The aminoacyl-tRNA synthetases are prominently known for their classic function in the first step of protein synthesis, where they bear the responsibility of setting the genetic code. Each enzyme is exquisitely adapted to covalently link a single standard amino acid to its cognate set of tRNA isoacceptors. These ancient enzymes have evolved idiosyncratically to host alternate activities that go far beyond their aminoacylation role and impact a wide range of other metabolic pathways and cell signaling processes. The family of aminoacyl-tRNA synthetases has also been suggested as a remarkable scaffold to incorporate new domains that would drive evolution and the emergence of new organisms with more complex function. Because they are essential, the tRNA synthetases have served as pharmaceutical targets for drug and antibiotic development. The recent unfolding of novel important functions for this family of proteins offers new and promising pathways for therapeutic development to treat diverse human diseases.
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Affiliation(s)
- Yan Ling Joy Pang
- Department of Biochemistry, University of Illinois at Urbana, Urbana, IL, USA
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15
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Kim JH, Lee JH, Park MC, Yoon I, Kim K, Lee M, Choi HS, Kim S, Han JM. AIMP1/p43 negatively regulates adipogenesis by inhibiting peroxisome proliferator-activated receptor gamma. J Cell Sci 2014; 127:4483-93. [DOI: 10.1242/jcs.154930] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Adipogenesis is known to be controlled by the concerted actions of transcription factors and co-regulators. However, little is known about the regulation mechanism of transcription factors that control adipogenesis. In addition, the adipogenic roles of translational factors remain unclear. Here, we show that aminoacyl-tRNA synthetase-interacting multifunctional protein 1 (AIMP1), an auxiliary factor that is associated with a macromolecular tRNA synthetase complex, negatively regulates adipogenesis via a direct interaction with the DNA-binding domain of peroxisome proliferator-activated receptor γ (PPARγ). AIMP1 expression increased during adipocyte differentiation. Adipogenesis was augmented in AIMP1-deficient cells, as compared with control cells. AIMP1 exhibited high affinity for active PPARγ and interacted with the DNA-binding domain of PPARγ, thereby inhibiting its transcriptional activity. Thus, AIMP1 appears to function as a novel inhibitor of PPARγ that regulates adipocyte differentiation by preventing the transcriptional activation of PPARγ.
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16
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Lee SW, Kim G, Kim S. Aminoacyl-tRNA synthetase-interacting multi-functional protein 1/p43: an emerging therapeutic protein working at systems level. Expert Opin Drug Discov 2013; 3:945-57. [PMID: 23484969 DOI: 10.1517/17460441.3.8.945] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
BACKGROUND Drug discovery programs are based on the presumption of one drug-one action-one disease, which is frustrated by the complexity of biological systems. Because the aberration of a single gene often leads to multiple pathological symptoms, we should understand the functional network of the disease-related proteins to develop effective therapy. OBJECTIVES To describe how activities of proteins are reflected in phenotypes and their pathological implications using aminoacyl-tRNA synthetase-interacting multi-functional protein 1 (AIMP1). METHODS The physiological activities of AIMP1 are unveiled through in vitro approaches and in vivo phenotyptic investigation. Bioinformatics tool was used to combine all AIMP1-target proteins. CONCLUSION Although a cytosolic protein, AIMP1 can be secreted as a cytokine to control immune response, angiogenesis and wound healing, and as a glucagon-like hormone for glucose homeostasis. It is involved in the regulation of autoimmune control and TGF-β signaling within the cells. AIMP1-deficient mice developed multiple phenotypes in immune systems, metabolism and body growth. The therapeutic potential of this multi-functional protein with associated biological activities are discussed.
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Affiliation(s)
- Sang Won Lee
- Seoul National University of Education, Department of Science and Technology Education for Life, 1650, Seocho-dong, Seocho-gu, Seoul 137-742, Korea
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17
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Huang QQ, Koessler RE, Birkett R, Dorfleutner A, Perlman H, Haines GK, Stehlik C, Nicchitta CV, Pope RM. Glycoprotein 96 perpetuates the persistent inflammation of rheumatoid arthritis. ACTA ACUST UNITED AC 2013; 64:3638-48. [PMID: 22777994 DOI: 10.1002/art.34610] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
OBJECTIVE The mechanisms that contribute to the persistent activation of macrophages in rheumatoid arthritis (RA) are incompletely understood. The aim of this study was to determine the contribution of endogenous gp96 in Toll-like receptor (TLR)-mediated macrophage activation in RA. METHODS RA synovial fluid was used to activate macrophages and HEK-TLR-2 and HEK-TLR-4 cells. Neutralizing antibodies to TLR-2, TLR-4, and gp96 were used to inhibit activation. RA synovial fluid macrophages were isolated by CD14 negative selection. Cell activation was measured by the expression of tumor necrosis factor α (TNFα) or interleukin-8 messenger RNA. Arthritis was induced in mice by K/BxN serum transfer. The expression of gp96 was determined by immunoblot analysis, enzyme-linked immunosorbent assay, and immunohistochemistry. Arthritis was treated with neutralizing anti-gp96 antiserum or control serum. RESULTS RA synovial fluid induced the activation of macrophages and HEK-TLR-2 and HEK-TLR-4 cells. RA synovial fluid-induced macrophage and HEK-TLR-2 activation was suppressed by neutralizing anti-gp96 antibodies only in the presence of high (>800 ng/ml) rather than low (<400 ng/ml) concentrations of gp96. Neutralization of RA synovial fluid macrophage cell surface gp96 inhibited the constitutive expression of TNFα. Supporting the role of gp96 in RA, joint tissue gp96 expression was induced in mice with the K/BxN serum-induced arthritis, and neutralizing antibodies to gp96 ameliorated joint inflammation, as determined by clinical and histologic examination. CONCLUSION These observations support the notion that gp96 plays a role as an endogenous TLR-2 ligand in RA and identify the TLR-2 pathway as a therapeutic target.
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Affiliation(s)
- Qi-Quan Huang
- Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
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18
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Protein-protein interactions and multi-component complexes of aminoacyl-tRNA synthetases. Top Curr Chem (Cham) 2013; 344:119-44. [PMID: 24072587 DOI: 10.1007/128_2013_479] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Protein-protein interaction occurs transiently or stably when two or more proteins bind together to mediate a wide range of cellular processes such as protein modification, signal transduction, protein trafficking, and structural folding. The macromolecules involved in protein biosynthesis such as aminoacyl-tRNA synthetase (ARS) have a number of protein-protein interactions. The mammalian multi-tRNA synthetase complex (MSC) consists of eight different enzymes: EPRS, IRS, LRS, QRS, MRS, KRS, RRS, and DRS, and three auxiliary proteins: AIMP1/p43, AIMP2/p38, and AIMP/p18. The distinct ARS proteins are also connected to diverse protein networks to carry out biological functions. In this chapter we first show the protein networks of the entire MSC and explain how MSC components interact with or can regulate other proteins. Finally, it is pointed out that the understanding of protein-protein interaction mechanism will provide insight to potential therapeutic application for diseases related to the MSC network.
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Huang QQ, Pope RM. The role of glycoprotein 96 in the persistent inflammation of rheumatoid arthritis. Arch Biochem Biophys 2012; 530:1-6. [PMID: 23257071 DOI: 10.1016/j.abb.2012.12.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 12/29/2022]
Abstract
The 96-kDa glycoprotein (gp96) is an endoplasmic reticulum (ER) resident molecular chaperone. Under physiologic conditions, gp96 facilitates the transport of toll-like receptors (TLRs) to cell or endosomal membranes. Under pathologic circumstances such as rheumatoid arthritis, gp96 translocates to the cell surface and extracellular space, serving as an endogenous danger signal promoting TLR signaling. Macrophages play a central role in regulating innate and adaptive immunity, and are the major source of proinflammatory cytokines and chemokines in rheumatoid arthritis (RA). Macrophage numbers in the sublining of RA synovial tissue correlate with clinical response. This review focuses on the recent findings that implicate gp96 induced macrophage activation mediated through TLR signaling in the pathogenesis of RA and provides insights concerning the targeting gp96 and the TLR signaling pathway as therapeutic approaches for patients with RA and possibly other chronic inflammatory conditions.
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Affiliation(s)
- Qi-Quan Huang
- Northwestern University Feinberg School of Medicine, Department of Medicine, Division of Rheumatology, 240 East Huron, McGaw M220, Chicago, IL 60611, USA.
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20
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AIMP1 deficiency enhances airway hyperreactivity in mice via increased TH2 immune responses. Clin Immunol 2012; 143:256-65. [PMID: 22472603 DOI: 10.1016/j.clim.2012.02.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Revised: 02/10/2012] [Accepted: 02/21/2012] [Indexed: 12/22/2022]
Abstract
Aminoacyl tRNA synthetase complex-interacting multicomplex protein 1 (AIMP1) is known as a novel cytokine carrying out a variety of biological activities, including angiogenesis and wound repair. In our previous reports AIMP1 was demonstrated to induce TH1 polarization. However, the effects of AIMP1 deficiency in TH1 or TH2 immune disorders remain unclear. In this study, we characterized phenotypes of AIMP1-deficient mice and investigated the role of AIMP1 in TH2-biased airway hyperreactivity. Clinical signs of allergic airway inflammation were assessed in AIMP1-deficient mice and the effects of AIMP1 deficiency on production of TH2 cytokines were evaluated in T cells using AIMP1-specific siRNA. Additionally, the enhanced pause values and histologic analysis were assessed in mice receiving AIMP1-deficient CD4+ T cells with OVA challenge. Clinical signs of spontaneous airway inflammation were noted in AIMP1-deficienct mice. AIMP1-deficient mice showed strongly increased Penh values in response to methacholine without any allergen exposure. Adoptive transfer of AIMP1-deficient CD4+ T cells to OVA-sensitized C57BL/6 mice exacerbated OVA-induced airway inflammation and increased infiltration of inflammatory cells into the lung. Furthermore, lung DCs in AIMP1-deficient mice showed increased expression of surface molecules, and IL-12p40 level in sera significantly decreased in AIMP1-deficient mice compared to that of wild type mice. These results strongly indicate that AIMP1 plays a role in negatively regulating TH2 responses in vivo, and AIMP1 can be employed as a novel therapeutic agent against TH2-biased diseases, particularly asthma.
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21
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Kwon HS, Park MC, Kim DG, Jo KW, Park YW, Han JM, Kim S. Identification of CD23 as a functional receptor for the proinflammatory cytokine AIMP1/p43. J Cell Sci 2012; 125:4620-9. [DOI: 10.1242/jcs.108209] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
ARS-interacting multifunctional protein 1 (AIMP1/p43) can be secreted to trigger proinflammatory molecules while it is predominantly bound to a cytoplasmic macromolecular protein complex that contains several different aminoacyl-tRNA synthetases. Although its activities as a secreted signaling factor have been well-characterized, the functional receptor for its proinflammatory activity has not yet identified. In this study, we have identified the receptor molecule for AIMP1 that mediates the secretion of TNF-α from THP-1 monocytic cells and primary human peripheral blood mononuclear cells (PBMCs). In a screen of 499 soluble receptors, we identified CD23, a known low-affinity receptor for IgE, as a high affinity binding partner of AIMP1. We found that down-regulation of CD23 attenuated AIMP1-induced TNF-α secretion and AIMP1 binding to THP-1 and PBMCs. We also observed that in THP-1 and PBMCs, AIMP1-induced TNF-α secretion mediated by CD23 involved activation of ERK1/2. Interestingly, endothelial monocyte activating polypeptide II (EMAP II), the C-terminal fragment of AIMP1 that is also known to work as a proinflammatory cytokine, was incapable of binding to CD23 and of activating ERK1/2. Therefore, identification of CD23 not only explains the inflammatory function of AIMP1 but also provides the first evidence by which the mode of action of AIMP1 can be distinguished from that of its C-terminal domain, EMAP II.
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22
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Jeon YH, Lee JY, Kim S. Chemical modulators working at pharmacological interface of target proteins. Bioorg Med Chem 2011; 20:1893-901. [PMID: 22227462 DOI: 10.1016/j.bmc.2011.12.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2011] [Revised: 11/30/2011] [Accepted: 12/08/2011] [Indexed: 01/23/2023]
Abstract
For last few decades, the active site cleft and substrate-binding site of enzymes as well as ligand-binding site of the receptors have served as the main pharmacological space for drug discovery. However, rapid accumulation of proteome and protein network analysis data has opened a new therapeutic space that is the interface between the interacting proteins. Due to the complexity of the interaction modes and the numbers of the participating components, it is still challenging to identify the chemicals that can accurately control the protein-protein interactions at desire. Nonetheless, the number of chemical drugs and candidates working at the interface of the interacting proteins are rapidly increasing. This review addresses the current case studies and state-of-the-arts in the development of small chemical modulators controlling the interactions of the proteins that have pathological implications in various human diseases such as cancer, immune disorders, neurodegenerative and infectious diseases.
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Affiliation(s)
- Young Ho Jeon
- Korea University College of Pharmacy Sejong-ro, Jochiwon, Yeonggi-gun, Chungnam 339-700, Republic of Korea
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23
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Jackson VC, Dewilde S, Albo AG, Lis K, Corpillo D, Canepa B. The activity of aminoacyl-tRNA synthetase-interacting multi-functional protein 1 (AIMP1) on endothelial cells is mediated by the assembly of a cytoskeletal protein complex. J Cell Biochem 2011; 112:1857-68. [DOI: 10.1002/jcb.23104] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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24
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Bajor A, Tischer S, Figueiredo C, Wittmann M, Immenschuh S, Blasczyk R, Eiz-Vesper B. Modulatory role of calreticulin as chaperokine for dendritic cell-based immunotherapy. Clin Exp Immunol 2011; 165:220-34. [PMID: 21635227 DOI: 10.1111/j.1365-2249.2011.04423.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Heat shock proteins (HSPs) play a regulatory role for maturation of antigen-presenting cells (APCs) such as dendritic cells (DCs) and macrophages. Whereas HSP70 has been shown to enhance the maturation of human DCs via a nuclear factor kappa-B (NF-κB)-dependent pathway, the regulatory role of calreticulin (CRT), which is a HSP with similar functions to HSP70, is not well studied. To investigate the role of CRT as adjuvant in cell activation and co-stimulatory responses we determined the effects of CRT on human APC maturation in comparison to that of HSP70. To facilitate eukaryotic endotoxin-free CRT protein expression, three different methods were compared. We demonstrate that CRT induces the maturation of human DCs and increases the production of proinflammatory cytokines via the NF-κB pathway. CRT-mediated maturation was qualitatively similar to that induced by HSP70. Interestingly, priming of monocytes with HSPs showed an even more prominent effect on maturation than exposure of immature DCs to these compounds. A higher expression of CD86, CD83 and CCR7 on mature DCs were found in response to CRT. Our data provide novel insights into the role of extracellular HSPs as chaperokines in the processes of APC generation and may thus be useful to improve adoptive immunotherapy.
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Affiliation(s)
- A Bajor
- Institute for Transfusion Medicine, Hannover Medical School, Hannover, Germany
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25
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Choi JW, Kim DG, Lee AE, Kim HR, Lee JY, Kwon NH, Shin YK, Hwang SK, Chang SH, Cho MH, Choi YL, Kim J, Oh SH, Kim B, Kim SY, Jeon HS, Park JY, Kang HP, Park BJ, Han JM, Kim S. Cancer-associated splicing variant of tumor suppressor AIMP2/p38: pathological implication in tumorigenesis. PLoS Genet 2011; 7:e1001351. [PMID: 21483803 PMCID: PMC3069106 DOI: 10.1371/journal.pgen.1001351] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2010] [Accepted: 02/23/2011] [Indexed: 11/26/2022] Open
Abstract
Although ARS-interacting multifunctional protein 2 (AIMP2, also named as MSC p38) was first found as a component for a macromolecular tRNA synthetase complex, it was recently discovered to dissociate from the complex and work as a potent tumor suppressor. Upon DNA damage, AIMP2 promotes apoptosis through the protective interaction with p53. However, it was not demonstrated whether AIMP2 was indeed pathologically linked to human cancer. In this work, we found that a splicing variant of AIMP2 lacking exon 2 (AIMP2-DX2) is highly expressed by alternative splicing in human lung cancer cells and patient's tissues. AIMP2-DX2 compromised pro-apoptotic activity of normal AIMP2 through the competitive binding to p53. The cells with higher level of AIMP2-DX2 showed higher propensity to form anchorage-independent colonies and increased resistance to cell death. Mice constitutively expressing this variant showed increased susceptibility to carcinogen-induced lung tumorigenesis. The expression ratio of AIMP2-DX2 to normal AIMP2 was increased according to lung cancer stage and showed a positive correlation with the survival of patients. Thus, this work identified an oncogenic splicing variant of a tumor suppressor, AIMP2/p38, and suggests its potential for anti-cancer target. Lung cancer is one of the most common cancers and a leading cause of death resulting from cancer. Despite intensive investigation, effective therapeutic targets and reliable biomarkers are still limited. Here we found that a tumor suppressor, AIMP2 (MSC p38), produces a variant lacking a part of its structure in cancer tissues. We designated it AIMP2-DX2. This smaller version of AIMP2 compromises the normal tumor suppressive activity of AIMP2 and induces tumor formation. We also found that the expression of AIMP2-DX2 was increased according to cancer progression. In addition, the patients with higher expression of AIMP2-DX2 showed lower survival than those with lower levels of this variant. Suppression of AIMP2-DX2 slowed tumor growth, suggesting it as a new therapeutic target. In summary, this work newly identified a tumor-inducing factor, AIMP2-DX2, that can be used as a therapeutic target and biomarker associated with lung cancer.
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Affiliation(s)
- Jin Woo Choi
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Dae Gyu Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Al-Eum Lee
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Hye Rim Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Jin Young Lee
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Nam Hoon Kwon
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
| | - Young Kee Shin
- Laboratory of Molecular Pathology, College of Pharmacy, Seoul National University, Seoul, Korea
| | - Soon-Kyung Hwang
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Seung-Hee Chang
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Myung-Haing Cho
- College of Veterinary Medicine, Seoul National University, Seoul, Korea
| | - Yoon-La Choi
- Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Jhingook Kim
- Department of Thoracic and Cardiovascular Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Seung Hyun Oh
- National Cancer Center, Research Institute, Goyang, Korea
| | - Bora Kim
- National Cancer Center, Research Institute, Goyang, Korea
| | - Soo-Youl Kim
- National Cancer Center, Research Institute, Goyang, Korea
| | - Hyo-Sung Jeon
- Department of Biochemistry, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Jae Yong Park
- Department of Internal Medicine, School of Medicine, Kyungpook National University, Daegu, Korea
| | - Hyunseok Peter Kang
- Department of Pathology and Laboratory Medicine, Roswell Cancer Park Institute, Buffalo, New York, United States of America
| | - Bum Joon Park
- Department of Molecular Biology, Pusan National University, Pusan, Korea
| | - Jung Min Han
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
- WCU Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University, Suwon, Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul, Korea
- WCU Department of Molecular Medicine and Biopharmaceutical Sciences, Seoul National University, Suwon, Korea
- * E-mail:
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26
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Ma WF, Chen HY, Du J, Tan Y, Cai SH. A novel recombinant protein TAT-GFP-KDEL with dual-function of penetrating cell membrane and locating at endoplasm reticulum. J Drug Target 2010; 17:329-33. [PMID: 19558358 DOI: 10.1080/10611860802582459] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Although the potential value of phenotypic/functional knockout technology with intrabody/kine in prevention and cure of some serious diseases, such as AIDS and cancer, is being regarded, there are still several technical difficulties. One of the the most critical problems is how to directly deliver the intrabody/kine proteins into endoplasm reticulum (ER). In this study, a novel recombinant protein, TAT-GFP-KDEL, was designed and constructed. In this recombinant protein, HIV-derived TAT (47-57) and an ER retention four-peptide sequence KDEL were fused at the N-terminal and C-terminal of GFP respectively. The results showed that TAT-GFP-KDEL had been successfully expressed in bacteria BL21 and its purity reached to 95%. Moreover, we observed that this recombinant protein was able to efficiently transduce into MOLT-4 cells and accurately locate at ER. This study may provide an available strategy to promote the transmembrane delivery and ER localization of protein-based intrabody/kine.
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Affiliation(s)
- Wei Feng Ma
- School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou 510515, PR China
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27
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Park SG, Choi EC, Kim S. Aminoacyl-tRNA synthetase-interacting multifunctional proteins (AIMPs): a triad for cellular homeostasis. IUBMB Life 2010; 62:296-302. [PMID: 20306515 DOI: 10.1002/iub.324] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Aminoacyl-tRNA synthetases (ARSs) are highly conserved for efficient and precise translation of genetic codes. In higher eukaryotic systems, several different ARSs including glutamyl-prolyl-, isoelucyl-, leucyl-, methionyl-, glutaminyl-, lysyl-, arginyl-, and aspartyl-tRNA synthetase form a macromolecular protein complex with three nonenzymatic cofactors (AIMP1/p43, AIMP2/p38, and AIMP3/p18). Although the structure and functional implications for this complex formation are not completely understood, rapidly accumulating evidences suggest that this complex would work as a molecular hub linked to the multiple signaling pathways that involve the components of enzymes and cofactors. In this article, the roles of three nonenzymatic components of the multi-tRNA synthetase complex in the assembly of the components and in cell regulation are addressed.
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Affiliation(s)
- Sang Gyu Park
- Department of Biomedical Science, CHA University, Yeoksam-dong, Kangnam-gu, Seoul, Korea
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28
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Kim G, Han JM, Kim S. Toll-like receptor 4-mediated c-Jun N-terminal kinase activation induces gp96 cell surface expression via AIMP1 phosphorylation. Biochem Biophys Res Commun 2010; 397:100-5. [DOI: 10.1016/j.bbrc.2010.05.075] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 05/13/2010] [Indexed: 02/06/2023]
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29
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Han JM, Kwon NH, Lee JY, Jeong SJ, Jung HJ, Kim HR, Li Z, Kim S. Identification of gp96 as a novel target for treatment of autoimmune disease in mice. PLoS One 2010; 5:e9792. [PMID: 20352117 PMCID: PMC2843739 DOI: 10.1371/journal.pone.0009792] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2010] [Accepted: 03/01/2010] [Indexed: 11/18/2022] Open
Abstract
Heat shock proteins have been implicated as endogenous activators for dendritic cells (DCs). Chronic expression of heat shock protein gp96 on cell surfaces induces significant DC activations and systemic lupus erythematosus (SLE)-like phenotypes in mice. However, its potential as a therapeutic target against SLE remains to be evaluated. In this work, we conducted chemical approach to determine whether SLE-like phenotypes can be compromised by controlling surface translocation of gp96. From screening of chemical library, we identified a compound that binds and suppresses surface presentation of gp96 by facilitating its oligomerization and retrograde transport to endoplasmic reticulum. In vivo administration of this compound reduced maturation of DCs, populations of antigen presenting cells, and activated B and T cells. The chemical treatment also alleviated the SLE-associated symptoms such as glomerulonephritis, proteinuria, and accumulation of anti-nuclear and -DNA antibodies in the SLE model mice resulting from chronic surface exposure of gp96. These results suggest that surface translocation of gp96 can be chemically controlled and gp96 as a potential therapeutic target to treat autoimmune disease like SLE.
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Affiliation(s)
- Jung Min Han
- Center for Medicinal Protein Network and Systems Biology, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
- Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Nam Hoon Kwon
- Center for Medicinal Protein Network and Systems Biology, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Jin Young Lee
- Center for Medicinal Protein Network and Systems Biology, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Seung Jae Jeong
- Center for Medicinal Protein Network and Systems Biology, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
| | - Hee Jung Jung
- Cancer & Infectious Disease Research Center, Bio-Organic Science Division, Korea Research Institute of Chemical Technology, Dae Jeon, Republic of Korea
| | - Hyeong Rae Kim
- Cancer & Infectious Disease Research Center, Bio-Organic Science Division, Korea Research Institute of Chemical Technology, Dae Jeon, Republic of Korea
| | - Zihai Li
- Center for Immunotherapy of Cancer and Infectious Diseases, University of Connecticut School of Medicine, Farmington, Connecticut, United States of America
| | - Sunghoon Kim
- Center for Medicinal Protein Network and Systems Biology, College of Pharmacy, Seoul National University, Seoul, Republic of Korea
- Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Suwon, Republic of Korea
- * E-mail:
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30
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Guo M, Schimmel P, Yang XL. Functional expansion of human tRNA synthetases achieved by structural inventions. FEBS Lett 2009; 584:434-42. [PMID: 19932696 DOI: 10.1016/j.febslet.2009.11.064] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2009] [Revised: 11/17/2009] [Accepted: 11/17/2009] [Indexed: 02/06/2023]
Abstract
Known as an essential component of the translational apparatus, the aminoacyl-tRNA synthetase family catalyzes the first step reaction in protein synthesis, that is, to specifically attach each amino acid to its cognate tRNA. While preserving this essential role, tRNA synthetases developed other roles during evolution. Human tRNA synthetases, in particular, have diverse functions in different pathways involving angiogenesis, inflammation and apoptosis. The functional diversity is further illustrated in the association with various diseases through genetic mutations that do not affect aminoacylation or protein synthesis. Here we review the accumulated knowledge on how human tRNA synthetases used structural inventions to achieve functional expansions.
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Affiliation(s)
- Min Guo
- The Skaggs Institute for Chemical Biology, Department of Molecular Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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31
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Ma WF, Du J, Fu LP, Fang R, Chen HY, Cai SH. Phenotypic knockout of CXCR4 by a novel recombinant protein TAT/54R/KDEL inhibits tumors metastasis. Mol Cancer Res 2009; 7:1613-21. [PMID: 19825996 DOI: 10.1158/1541-7786.mcr-09-0078] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The chemokine receptor, CXCR4, and its specific ligand, CXCL12, have been proven to regulate the directional trafficking and invasion of breast cancer cells to sites of metastases, and similar phenomena have also been identified in many malignant tumors that aberrantly overexpress CXCR4. Therefore, blocking the interaction between CXCR4 and CXCL12 is considered a possible approach to efficiently prevent cancer metastasis. Employing a cellular phenotypic knockout strategy based on intrakines, we developed a novel recombinant chimeric protein, TAT/54R/KDEL, which contains three distinct functional domains: CXCL12/54R, a mutant of CXCL12 with CXCR4 antagonism, as well as HIV-derived TAT (47-57) and an endoplasmic reticulum retention four-peptide sequence KDEL that links at its NH(2) and COOH termini, respectively. Using the MOLT-4 cell line, which expressed CXCR4 highly and stably in vitro, we determined that TAT/54R/KDEL was able to efficiently transfer into the endoplasmic reticulum of tumor cells, where it specifically binds to the newly synthesized CXCR4 and prevents the latter from reaching the surface. Chemotaxis assays showed that the cells treated with TAT/54R/KDEL failed to migrate toward CXCL12. Furthermore, we observed that the systemic treatment of TAT/54R/KDEL could impair lung metastasis in a highly metastatic mammary cancer cell line, 4T1 cells, with the decrease of CXCR4 on their membrane. Our results suggest that the phenotypic knockout strategy of CXCR4 using a novel recombinant protein TAT/54R/KDEL might be a possible approach for inhibiting relative tumor metastasis mediated by CXCR4/CXCL12 interaction.
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Affiliation(s)
- Wei-Feng Ma
- Department of Microbiology, School of Public Health and Tropical Medicine, Southern Medical University, Guangzhou, P.R. China
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32
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Abstract
Neuron connectivity and correct neural function largely depend on axonal integrity. Neurofilaments (NFs) constitute the main cytoskeletal network maintaining the structural integrity of neurons and exhibit dynamic changes during axonal and dendritic growth. However, the mechanisms underlying axonal development and maintenance remain poorly understood. Here, we identify that multisynthetase complex p43 (MSC p43) is essential for NF assembly and axon maintenance. The MSC p43 protein was predominantly expressed in central neurons and interacted with NF light subunit in vivo. Mice lacking MSC p43 exhibited axon degeneration in motor neurons, defective neuromuscular junctions, muscular atrophy, and motor dysfunction. Furthermore, MSC p43 depletion in mice caused disorganization of the axonal NF network. Mechanistically, MSC p43 is required for maintaining normal phosphorylation levels of NFs. Thus, MSC p43 is indispensable in maintaining axonal integrity. Its dysfunction may underlie the NF disorganization and axon degeneration associated with motor neuron degenerative diseases.
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Choi JW, Kim DG, Park MC, Um JY, Han JM, Park SG, Choi EC, Kim S. AIMP2 promotes TNFalpha-dependent apoptosis via ubiquitin-mediated degradation of TRAF2. J Cell Sci 2009; 122:2710-5. [PMID: 19584093 DOI: 10.1242/jcs.049767] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
AIMP2 (aminoacyl-tRNA synthetase interacting multifunctional protein 2; also known as JTV-1) was first identified as p38 in a macromolecular protein complex that consisted of nine different aminoacyl-tRNA synthetases and two other auxiliary factors. AIMP2 also plays pivotal roles in the regulation of cell proliferation and death. Although AIMP2 was previously shown to augment TNFalpha-induced cell death, its working mechanism in this signal pathway was not understood. Here, we investigate the functional significance and mode of action of AIMP2 in TNFalpha signaling. TNFalpha-induced cell death was compromised in AIMP2-deficient or -suppressed cells and exogenous supplementation of AIMP2 augmented apoptotic sensitivity to TNFalpha signaling. This activity was confirmed by the AIMP2-dependent increase of IkappaB and suppression of NFkappaB. We found binding of AIMP2 to TRAF2, a key player in the TNFalpha signaling pathway. AIMP2 augmented the association of an E3 ubiquitin ligase, c-IAP1, with TRAF2, causing ubiquitin-dependent degradation of TRAF2. These findings suggest that AIMP2 can mediate the pro-apoptotic activity of TNFalpha via the downregulation of TRAF2 expression.
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Affiliation(s)
- Jin Woo Choi
- Center for Medicinal Protein Network and Systems Biology, Department of Molecular Medicine, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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Huang QQ, Sobkoviak R, Jockheck-Clark AR, Shi B, Mandelin AM, Tak PP, Haines GK, Nicchitta CV, Pope RM. Heat shock protein 96 is elevated in rheumatoid arthritis and activates macrophages primarily via TLR2 signaling. THE JOURNAL OF IMMUNOLOGY 2009; 182:4965-73. [PMID: 19342676 DOI: 10.4049/jimmunol.0801563] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Macrophages are important mediators of chronic inflammation and are prominent in the synovial lining and sublining of patients with rheumatoid arthritis (RA). Recently, we demonstrated increased TLR2 and TLR4 expression and increased response to microbial TLR2 and TLR4 ligands in macrophages from the joints of RA. The current study characterized the expression of the 96-kDa heat shock glycoprotein (gp96) in the joints of RA and its role as an endogenous TLR ligand to promote innate immunity in RA. gp96 was increased in RA compared with osteoarthritis and arthritis-free control synovial tissues. The expression of gp96 strongly correlated with inflammation and synovial lining thickness. gp96 was increased in synovial fluid from the joints of RA compared with disease controls. Recombinant gp96 was a potent activator of macrophages and the activation was mediated primarily through TLR2 signaling. The cellular response to gp96 was significantly stronger with RA synovial macrophages compared with peripheral blood monocytes from RA or healthy controls. The transcription of TLR2, TNF-alpha, and IL-8, but not TLR4, was significantly induced by gp96, and the induction was significantly greater in purified RA synovial macrophages. The expression of TLR2, but not TLR4, on synovial fluid macrophages strongly correlated with the level of gp96 in the synovial fluid. The present study documents the potential role of gp96 as an endogenous TLR2 ligand in RA and provides insight into the mechanism by which gp96 promotes the chronic inflammation of RA, identifying gp96 as a potential new therapeutic target.
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Affiliation(s)
- Qi-Quan Huang
- Department of Medicine, Division of Rheumatology, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA
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Abstract
Aminoacylation of transfer RNAs establishes the rules of the genetic code. The reactions are catalyzed by an ancient group of 20 enzymes (one for each amino acid) known as aminoacyl tRNA synthetases (AARSs). Surprisingly, the etiology of specific diseases-including cancer, neuronal pathologies, autoimmune disorders, and disrupted metabolic conditions-is connected to specific aminoacyl tRNA synthetases. These connections include heritable mutations in the genes for tRNA synthetases that are causally linked to disease, with both dominant and recessive disease-causing mutations being annotated. Because some disease-causing mutations do not affect aminoacylation activity or apparent enzyme stability, the mutations are believed to affect functions that are distinct from aminoacylation. Examples include enzymes that are secreted as procytokines that, after activation, operate in pathways connected to the immune system or angiogenesis. In addition, within cells, synthetases form multiprotein complexes with each other or with other regulatory factors and in that way control diverse signaling pathways. Although much has been uncovered in recent years, many novel functions, disease connections, and interpathway connections of tRNA synthetases have yet to be worked out.
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Lee YS, Han JM, Son SH, Choi JW, Jeon EJ, Bae SC, Park YI, Kim S. AIMP1/p43 downregulates TGF-β signaling via stabilization of smurf2. Biochem Biophys Res Commun 2008; 371:395-400. [DOI: 10.1016/j.bbrc.2008.04.099] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2008] [Accepted: 04/15/2008] [Indexed: 11/25/2022]
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Dhodapkar MV, Dhodapkar KM, Li Z. Role of chaperones and FcgammaR in immunogenic death. Curr Opin Immunol 2008; 20:512-7. [PMID: 18572395 DOI: 10.1016/j.coi.2008.05.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 05/07/2008] [Accepted: 05/08/2008] [Indexed: 12/22/2022]
Abstract
Cell death under physiologic conditions does not lead to the induction of immunity. However recognition of stressed or opsonized cells can trigger immune responses. Recent studies have begun to illustrate the critical role of molecular chaperones such as inducible heat shock proteins in mediating immunogenicity of stressed cells. Immunity to opsonized cells depends in part on the engagement and the balance of activating and inhibitory FcgammaRs on antigen presenting dendritic cells. Understanding both these pathways of immunogenic cell death may yield novel approaches to regulate immunity.
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Kapoor M, Zhou Q, Otero F, Myers CA, Bates A, Belani R, Liu J, Luo JK, Tzima E, Zhang DE, Yang XL, Schimmel P. Evidence for Annexin II-S100A10 Complex and Plasmin in Mobilization of Cytokine Activity of Human TrpRS. J Biol Chem 2008; 283:2070-7. [DOI: 10.1074/jbc.m706028200] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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