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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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Transcriptome sequencing reveals improved ammonia nitrogen tolerance in Zebra II strain of the Manila clam Ruditapes philippinarum. COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY. PART D, GENOMICS & PROTEOMICS 2022; 44:101016. [PMID: 35985189 DOI: 10.1016/j.cbd.2022.101016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2022] [Revised: 07/24/2022] [Accepted: 07/24/2022] [Indexed: 01/27/2023]
Abstract
In this research, we identified genes associated with ammonia nitrogen (TAN) stress response and resistance in juveniles of the Zebra II strain and a wild population of the Manila clam Ruditapes philippinarum. Both groups were subjected to a 96 h acute toxicity test using TAN concentrations of 17.617 ± 0.634 and 16.670 ± 0.7 mg/l, respectively. We then collected samples, conducted transcriptome sequencing and screened the sequences for differentially expressed genes (DEGs) related to TAN stress response. We identified 2908 and 2861 DEGs in the Zebra II and wild clam groups, respectively, and the two groups had 626 DEGs in common. The verified DEGs had less of a detoxification effect in the wild population than that in the Zebra II group. Gene Ontology database analysis showed that Zebra II juveniles were mainly enriched in protein phosphorylation, purine nucleoside binding, and kinase activity, whereas the wild population juveniles were primarily enriched in oxidases activity, organic acid metabolic processes, and extracellular regions. Kyoto Encyclopedia of Genes and Genomes pathway analysis mainly highlighted aminoacyl tRNA biosynthesis in Zebra II juveniles and sphingolipid metabolism, FOXO signaling, biosynthesis of aminoacyl tRNA, and other pathways in the wild population. These results show that the toxic effect of TAN on the Manila clam is related to a variety of pathways, which are mainly related to immune response, inflammatory response, metabolic pathways, and nerve conduction. This study provides basic data and theoretical reference for revealing the molecular regulation mechanism of the improved TAN tolerance of Zebra II strain as compared with the wild population of Ruditapes philippinarum.
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Jaramillo Ponce JR, Kapps D, Paulus C, Chicher J, Frugier M. Discovery of two distinct aminoacyl-tRNA synthetase complexes anchored to the Plasmodium surface tRNA import protein. J Biol Chem 2022; 298:101987. [PMID: 35487244 PMCID: PMC9136112 DOI: 10.1016/j.jbc.2022.101987] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 04/19/2022] [Accepted: 04/20/2022] [Indexed: 11/21/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) attach amino acids to their cognate transfer RNAs. In eukaryotes, a subset of cytosolic aaRSs is organized into a multisynthetase complex (MSC), along with specialized scaffolding proteins referred to as aaRS-interacting multifunctional proteins (AIMPs). In Plasmodium, the causative agent of malaria, the tRNA import protein (tRip), is a membrane protein that participates in tRNA trafficking; we show that tRip also functions as an AIMP. We identified three aaRSs, the glutamyl-tRNA synthetase (ERS), glutaminyl-tRNA synthetase (QRS), and methionyl-tRNA synthetase (MRS), which were specifically coimmunoprecipitated with tRip in Plasmodium berghei blood stage parasites. All four proteins contain an N-terminal glutathione-S-transferase (GST)-like domain that was demonstrated to be involved in MSC assembly. In contrast to previous studies, further dissection of GST-like interactions identified two exclusive heterotrimeric complexes: the Q-complex (tRip-ERS-QRS) and the M-complex (tRip-ERS-MRS). Gel filtration and light scattering suggest a 2:2:2 stoichiometry for both complexes but with distinct biophysical properties and mutational analysis further revealed that the GST-like domains of QRS and MRS use different strategies to bind ERS. Taken together, our results demonstrate that neither the singular homodimerization of tRip nor its localization in the parasite plasma membrane prevents the formation of MSCs in Plasmodium. Besides, the extracellular localization of the tRNA-binding module of tRip is compensated by the presence of additional tRNA-binding modules fused to MRS and QRS, providing each MSC with two spatially distinct functions: aminoacylation of intraparasitic tRNAs and binding of extracellular tRNAs. This unique host-pathogen interaction is discussed.
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Affiliation(s)
- José R Jaramillo Ponce
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Delphine Kapps
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Caroline Paulus
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France
| | - Johana Chicher
- Strasbourg-Esplanade Proteomics Facility, Université de Strasbourg, Strasbourg, France
| | - Magali Frugier
- Université de Strasbourg, CNRS, Architecture et Réactivité de l'ARN, UPR 9002, Strasbourg, France.
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Liang YY, Bacanu S, Sreekumar L, Ramos AD, Dai L, Michaelis M, Cinatl J, Seki T, Cao Y, Coffill CR, Lane DP, Prabhu N, Nordlund P. CETSA interaction proteomics define specific RNA-modification pathways as key components of fluorouracil-based cancer drug cytotoxicity. Cell Chem Biol 2022; 29:572-585.e8. [PMID: 34265272 DOI: 10.1016/j.chembiol.2021.06.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 05/14/2021] [Accepted: 06/25/2021] [Indexed: 12/18/2022]
Abstract
The optimal use of many cancer drugs is hampered by a lack of detailed understanding of their mechanism of action (MoA). Here, we apply a high-resolution implementation of the proteome-wide cellular thermal shift assay (CETSA) to follow protein interaction changes induced by the antimetabolite 5-fluorouracil (5-FU) and related nucleosides. We confirm anticipated effects on the known main target, thymidylate synthase (TYMS), and enzymes in pyrimidine metabolism and DNA damage pathways. However, most interaction changes we see are for proteins previously not associated with the MoA of 5-FU, including wide-ranging effects on RNA-modification and -processing pathways. Attenuated responses of specific proteins in a resistant cell model identify key components of the 5-FU MoA, where intriguingly the abrogation of TYMS inhibition is not required for cell proliferation.
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Affiliation(s)
- Ying Yu Liang
- Institute of Molecular and Cell Biology, A∗STAR, Singapore 138673, Singapore; Department of Oncology and Pathology, Karolinska Institutet, 171 77 Stockholm, Sweden; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Smaranda Bacanu
- Department of Oncology and Pathology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Lekshmy Sreekumar
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Anderson Daniel Ramos
- Department of Oncology and Pathology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Lingyun Dai
- Institute of Molecular and Cell Biology, A∗STAR, Singapore 138673, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Martin Michaelis
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK
| | - Jindrich Cinatl
- Institute for Medical Virology, Goethe-University, Frankfurt am Main, Germany
| | - Takahiro Seki
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden; Kagoshima University Graduate School of Medical and Dental Sciences 8 Chome-35-1 Sakuragaoka, Kagoshima 890-8520, Japan
| | - Yihai Cao
- Department of Microbiology, Tumour and Cell Biology, Karolinska Institutet, 171 77 Stockholm, Sweden
| | - Cynthia R Coffill
- p53Lab, A∗STAR, 8A Biomedical Groove, Immunos, #06-06, Singapore 138648, Singapore
| | - David P Lane
- p53Lab, A∗STAR, 8A Biomedical Groove, Immunos, #06-06, Singapore 138648, Singapore
| | - Nayana Prabhu
- Institute of Molecular and Cell Biology, A∗STAR, Singapore 138673, Singapore; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Pär Nordlund
- Institute of Molecular and Cell Biology, A∗STAR, Singapore 138673, Singapore; Department of Oncology and Pathology, Karolinska Institutet, 171 77 Stockholm, Sweden; School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore.
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Tian H, Yan H, Zhang Y, Fu Q, Li C, He J, Li H, Zhou Y, Huang Y, Li R. Knockdown of mitochondrial threonyl-tRNA synthetase 2 inhibits lung adenocarcinoma cell proliferation and induces apoptosis. Bioengineered 2022; 13:5190-5204. [PMID: 35184682 PMCID: PMC8974053 DOI: 10.1080/21655979.2022.2037368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Lung cancer is a significant global burden. Aminoacyl-tRNA synthetases (aaRSs) can be reliably identified by the occurrence and improvement of tumors. Threonyl-tRNA synthetase (TARS) and mitochondrial threonyl-tRNA synthetase 2 (TARS2) are both aaRSs. Many studies have shown that TARS are involved in tumor angiogenesis and metastasis. However, TARS2 has not yet been reported in tumors. This study explored the role of TARS2 in the proliferation and apoptosis of lung adenocarcinoma (LUAD). TARS2 expression in lung adenocarcinoma and non-cancerous lung tissues was detected via immunohistochemistry. Cell proliferation was detected using MTS, clone formation, and EdU staining assays. Flow cytometry was used to detect cell cycle, mitochondria reactive oxygen species (mROS) production, and apoptosis. Mitochondrial membrane potential (MMP ΔΨm) was detected using JC-1 fluorescent probes. Cell cycle, apoptosis-related pathway, and mitochondrial DNA (mtDNA) -encoded protein expression was detected via Western blotting. Finally, the effect of TARS2 on tumor growth was examined using a xenotransplanted tumor model in nude mice. We found that TARS2 was highly expressed in lung adenocarcinoma tissues and associated with poor overall survival (OS). Mechanistic analysis showed that knockdown of TARS2 inhibited proliferation through the retinoblastoma protein (RB) pathway and promoted mROS-induced apoptosis. Knockdown of TARS2 inhibits tumor growth in a xenotransplanted tumor model. TARS2 plays an important role in LUAD cell proliferation and apoptosis and may be a new therapeutic target.
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Affiliation(s)
- Hui Tian
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Hao Yan
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Yong Zhang
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Qiaofen Fu
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Chunyan Li
- Department of Head and Neck Surgery Section II, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province), Kunming, Yunnan, China
| | - Juan He
- Department of Dermatology and Venereology, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Hui Li
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Yong Zhou
- Division Department of Thoracic Surgery Organization, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
- Centre for Experimental Studies and Research, First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
| | - Youguang Huang
- Department of Yunnan Tumor Research Institute, The Third Affiliated Hospital of Kunming Medical University (Tumor Hospital of Yunnan Province), Kunming, China
| | - Rongqing Li
- Department of Radiation Oncology, The First Affiliated Hospital of Kunming Medical University, Kunming, Yunnan, China
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Abstract
The aminoacyl-tRNA synthetases are an essential and universally distributed family of enzymes that plays a critical role in protein synthesis, pairing tRNAs with their cognate amino acids for decoding mRNAs according to the genetic code. Synthetases help to ensure accurate translation of the genetic code by using both highly accurate cognate substrate recognition and stringent proofreading of noncognate products. While alterations in the quality control mechanisms of synthetases are generally detrimental to cellular viability, recent studies suggest that in some instances such changes facilitate adaption to stress conditions. Beyond their central role in translation, synthetases are also emerging as key players in an increasing number of other cellular processes, with far-reaching consequences in health and disease. The biochemical versatility of the synthetases has also proven pivotal in efforts to expand the genetic code, further emphasizing the wide-ranging roles of the aminoacyl-tRNA synthetase family in synthetic and natural biology.
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Affiliation(s)
- Miguel Angel Rubio Gomez
- Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA Department of Microbiology, The Ohio State University, Columbus, Ohio 43210, USA
| | - Michael Ibba
- Center for RNA Biology, The Ohio State University, Columbus, Ohio 43210, USA Department of Microbiology, The Ohio State University, Columbus, Ohio 43210, USA
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A Novel Methoxybenzyl 5-Nitroacridone Derivative Effectively Triggers G1 Cell Cycle Arrest in Chronic Myelogenous Leukemia K562 Cells by Inhibiting CDK4/6-Mediated Phosphorylation of Rb. Int J Mol Sci 2020; 21:ijms21145077. [PMID: 32708403 PMCID: PMC7403985 DOI: 10.3390/ijms21145077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 07/16/2020] [Accepted: 07/17/2020] [Indexed: 01/12/2023] Open
Abstract
Chronic myeloid leukemia (CML) is a malignant tumor caused by the abnormal proliferation of hematopoietic stem cells. Among a new series of acridone derivatives previously synthesized, it was found that the methoxybenzyl 5-nitroacridone derivative 8q has nanomolar cytotoxicity in vitro against human chronic myelogenous leukemia K562 cells. In order to further explore the possible anti-leukemia mechanism of action of 8q on K562 cells, a metabolomics and molecular biology study was introduced. It was thus found that most of the metabolic pathways of the G1 phase of K562 cells were affected after 8q treatment. In addition, a concentration-dependent accumulation of cells in the G1 phase was observed by cell cycle analysis. Western blot analysis showed that 8q significantly down-regulated the phosphorylation level of retinoblastoma-associated protein (Rb) in a concentration-dependent manner, upon 48 h treatment. In addition, 8q induced K562 cells apoptosis, through both mitochondria-mediated and exogenous apoptotic pathways. Taken together, these results indicate that 8q effectively triggers G1 cell cycle arrest and induces cell apoptosis in K562 cells, by inhibiting the CDK4/6-mediated phosphorylation of Rb. Furthermore, the possible binding interactions between 8q and CDK4/6 protein were clarified by homology modeling and molecular docking. In order to verify the inhibitory activity of 8q against other chronic myeloid leukemia cells, KCL-22 cells and K562 adriamycin-resistant cells (K562/ADR) were selected for the MTT assay. It is worth noting that 8q showed significant anti-proliferative activity against these cell lines after 48 h/72 h treatment. Therefore, this study provides new mechanistic information and guidance for the development of new acridones for application in the treatment of CML.
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Khadzhieva MB, Kuzovlev AN, Salnikova LE. Pneumonia: host susceptibility and shared genetics with pulmonary function and other traits. Clin Exp Immunol 2019; 198:367-380. [PMID: 31487037 DOI: 10.1111/cei.13367] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/29/2019] [Indexed: 12/16/2022] Open
Abstract
Pneumonia is a common and severe infectious lung disease. Host genetics, together with underlying medical and lifestyle conditions, determine pneumonia susceptibility. We performed a secondary analysis of the results of two genome-wide studies for pneumonia in 23andMe participants (40 600 cases/90 039 controls) (Tian et al., 2017) and UK Biobank (BB) participants (12 614 cases/324 585 controls) (via the Global Biobank Engine) and used the GTEx database to correlate the results with expression quantitative trait loci (eQTLs) data in lung and whole blood. In the 23andMe pneumonia single nucleotide polymorphism (SNP) set, 177 genotyped SNPs in the human leukocyte antigen (HLA) region satisfied the genome-wide significance level, P ≤ 5·0E-08. Several target genes (e.g. C4A, VARS2, SFTA2, HLA-C, HLA-DQA2) were unidirectionally regulated by many HLA eSNPs associated with a higher risk of pneumonia. In lung, C4A transcript was up-regulated by 291 pneumonia risk alleles spanning the half the HLA region. Among SNPs correlated with the expression levels of SFTA2 and VARS2, approximately 75% overlapped: all risk alleles were associated with VARS2 up-regulation and SFTA2 down-regulation. To find shared gene loci between pneumonia and pulmonary function (PF), we used data from the Global Biobank Engine and literature on genome-wide association studies (GWAS) of PF in general populations. Numerous gene loci overlapped between pneumonia and PF: 28·8% in the BB data set and 49·2% in the 23andMe data set. Enrichment analysis within the database of Genotypes and Phenotypes (dbGaP) and National Human Genome Research Institute-European Bioinformatics Institute (NHGRI-EBI) Catalog of pneumonia and pneumonia/PF gene sets identified significant overlap between these gene sets and genes related to inflammatory, developmental, neuropsychiatric and cardiovascular and obesity-related traits.
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Affiliation(s)
- M B Khadzhieva
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.,N. I. Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia.,Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
| | - A N Kuzovlev
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia
| | - L E Salnikova
- Federal Research and Clinical Center of Intensive Care Medicine and Rehabilitology, Moscow, Russia.,N. I. Vavilov Institute of General Genetics, Russian Academy of Sciences, Moscow, Russia.,Dmitry Rogachev National Research Center of Pediatric Hematology, Oncology and Immunology, Moscow, Russia
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Nyamai DW, Tastan Bishop Ö. Aminoacyl tRNA synthetases as malarial drug targets: a comparative bioinformatics study. Malar J 2019; 18:34. [PMID: 30728021 PMCID: PMC6366043 DOI: 10.1186/s12936-019-2665-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 01/27/2019] [Indexed: 01/08/2023] Open
Abstract
BACKGROUND Treatment of parasitic diseases has been challenging due to evolution of drug resistant parasites, and thus there is need to identify new class of drugs and drug targets. Protein translation is important for survival of malarial parasite, Plasmodium, and the pathway is present in all of its life cycle stages. Aminoacyl tRNA synthetases are primary enzymes in protein translation as they catalyse amino acid addition to the cognate tRNA. This study sought to understand differences between Plasmodium and human aminoacyl tRNA synthetases through bioinformatics analysis. METHODS Plasmodium berghei, Plasmodium falciparum, Plasmodium fragile, Plasmodium knowlesi, Plasmodium malariae, Plasmodium ovale, Plasmodium vivax, Plasmodium yoelii and human aminoacyl tRNA synthetase sequences were retrieved from UniProt database and grouped into 20 families based on amino acid specificity. These families were further divided into two classes. Both families and classes were analysed. Motif discovery was carried out using the MEME software, sequence identity calculation was done using an in-house Python script, multiple sequence alignments were performed using PROMALS3D and TCOFFEE tools, and phylogenetic tree calculations were performed using MEGA vs 7.0 tool. Possible alternative binding sites were predicted using FTMap webserver and SiteMap tool. RESULTS Motif discovery revealed Plasmodium-specific motifs while phylogenetic tree calculations showed that Plasmodium proteins have different evolutionary history to the human homologues. Human aaRSs sequences showed low sequence identity (below 40%) compared to Plasmodium sequences. Prediction of alternative binding sites revealed potential druggable sites in PfArgRS, PfMetRS and PfProRS at regions that are weakly conserved when compared to the human homologues. Multiple sequence analysis, motif discovery, pairwise sequence identity calculations and phylogenetic tree analysis showed significant differences between parasite and human aaRSs proteins despite functional and structural conservation. These differences may provide a basis for further exploration of Plasmodium aminoacyl tRNA synthetases as potential drug targets. CONCLUSION This study showed that, despite, functional and structural conservation, Plasmodium aaRSs have key differences from the human homologues. These differences in Plasmodium aaRSs can be targeted to develop anti-malarial drugs with less toxicity to the host.
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Affiliation(s)
- Dorothy Wavinya Nyamai
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa
| | - Özlem Tastan Bishop
- Research Unit in Bioinformatics (RUBi), Department of Biochemistry and Microbiology, Rhodes University, Grahamstown, 6140, South Africa.
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Na W, Wu YY, Gong PF, Wu CY, Cheng BH, Wang YX, Wang N, Du ZQ, Li H. Embryonic transcriptome and proteome analyses on hepatic lipid metabolism in chickens divergently selected for abdominal fat content. BMC Genomics 2018; 19:384. [PMID: 29792171 PMCID: PMC5966864 DOI: 10.1186/s12864-018-4776-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 05/10/2018] [Indexed: 12/19/2022] Open
Abstract
Background In avian species, liver is the main site of de novo lipogenesis, and hepatic lipid metabolism relates closely to adipose fat deposition. Using our fat and lean chicken lines of striking differences in abdominal fat content, post-hatch lipid metabolism in both liver and adipose tissues has been studied extensively. However, whether molecular discrepancy for hepatic lipid metabolism exists in chicken embryos remains obscure. Results We performed transcriptome and proteome profiling on chicken livers at five embryonic stages (E7, E12, E14, E17 and E21) between the fat and lean chicken lines. At each stage, 521, 141, 882, 979 and 169 differentially expressed genes were found by the digital gene expression, respectively, which were significantly enriched in the metabolic, PPAR signaling and fatty acid metabolism pathways. Quantitative proteomics analysis found 20 differentially expressed proteins related to lipid metabolism, PPAR signaling, fat digestion and absorption, and oxidative phosphorylation pathways. Combined analysis showed that genes and proteins related to lipid transport (intestinal fatty acid-binding protein, nucleoside diphosphate kinase, and apolipoprotein A-I), lipid clearance (heat shock protein beta-1) and energy metabolism (NADH dehydrogenase [ubiquinone] 1 beta subcomplex subunit 10 and succinate dehydrogenase flavoprotein subunit) were significantly differentially expressed between the two lines. Conclusions For hepatic lipid metabolism at embryonic stages, molecular differences related to lipid transport, lipid clearance and energy metabolism exist between the fat and lean chicken lines, which might contribute to the striking differences of abdominal fat deposition at post-hatch stages. Electronic supplementary material The online version of this article (10.1186/s12864-018-4776-9) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Wei Na
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Yuan-Yuan Wu
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Peng-Fei Gong
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Chun-Yan Wu
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Bo-Han Cheng
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Yu-Xiang Wang
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Ning Wang
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Zhi-Qiang Du
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Hui Li
- Key Laboratory of Chicken Genetics and Breeding, Ministry of Agriculture, Key Laboratory of Animal Genetics, Breeding and Reproduction, Education Department of Heilongjiang Province, College of Animal Science and Technology, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
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11
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Dai L, Zhao T, Bisteau X, Sun W, Prabhu N, Lim YT, Sobota RM, Kaldis P, Nordlund P. Modulation of Protein-Interaction States through the Cell Cycle. Cell 2018; 173:1481-1494.e13. [PMID: 29706543 DOI: 10.1016/j.cell.2018.03.065] [Citation(s) in RCA: 95] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2017] [Revised: 01/25/2018] [Accepted: 03/26/2018] [Indexed: 11/25/2022]
Abstract
Global profiling of protein expression through the cell cycle has revealed subsets of periodically expressed proteins. However, expression levels alone only give a partial view of the biochemical processes determining cellular events. Using a proteome-wide implementation of the cellular thermal shift assay (CETSA) to study specific cell-cycle phases, we uncover changes of interaction states for more than 750 proteins during the cell cycle. Notably, many protein complexes are modulated in specific cell-cycle phases, reflecting their roles in processes such as DNA replication, chromatin remodeling, transcription, translation, and disintegration of the nuclear envelope. Surprisingly, only small differences in the interaction states were seen between the G1 and the G2 phase, suggesting similar hardwiring of biochemical processes in these two phases. The present work reveals novel molecular details of the cell cycle and establishes proteome-wide CETSA as a new strategy to study modulation of protein-interaction states in intact cells.
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Affiliation(s)
- Lingyun Dai
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Tianyun Zhao
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Xavier Bisteau
- Institute of Molecular and Cell Biology, A(∗)STAR, Singapore 138673, Singapore
| | - Wendi Sun
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Nayana Prabhu
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Yan Ting Lim
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore
| | - Radoslaw M Sobota
- Institute of Molecular and Cell Biology, A(∗)STAR, Singapore 138673, Singapore; Institute of Medical Biology, A(∗)STAR, Singapore 138648, Singapore
| | - Philipp Kaldis
- Institute of Molecular and Cell Biology, A(∗)STAR, Singapore 138673, Singapore; Department of Biochemistry, National University of Singapore, Singapore 117597, Singapore
| | - Pär Nordlund
- School of Biological Sciences, Nanyang Technological University, Singapore 637551, Singapore; Institute of Molecular and Cell Biology, A(∗)STAR, Singapore 138673, Singapore; Department of Oncology and Pathology, Karolinska Institutet, 17177 Stockholm, Sweden.
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12
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Leibovitch M, Topisirovic I. Dysregulation of mRNA translation and energy metabolism in cancer. Adv Biol Regul 2017; 67:30-39. [PMID: 29150352 DOI: 10.1016/j.jbior.2017.11.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 10/26/2017] [Accepted: 11/01/2017] [Indexed: 12/20/2022]
Abstract
Dysregulated mRNA translation and aberrant energy metabolism are frequent in cancer. Considering that mRNA translation is an energy demanding process, cancer cells must produce sufficient ATP to meet energy demand of hyperactive translational machinery. In recent years, the mammalian/mechanistic target of rapamycin (mTOR) emerged as a central regulatory node which coordinates energy consumption by the translation apparatus and ATP production in mitochondria. Aberrant mTOR signaling underpins the vast majority of cancers whereby increased mTOR activity is thought to be a major determinant of both malignant translatomes and metabolomes. Nonetheless, the role of mTOR and other related signaling nodes (e.g. AMPK) in orchestrating protein synthesis and cancer energetics is only recently being unraveled. In this review, we discuss recent findings that provide insights into the molecular underpinnings of coordination of translational and metabolic programs of cancer cells, and potential strategies to translate these findings into clinical treatments.
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Affiliation(s)
- Matthew Leibovitch
- Lady Davis Institute, SMBD JGH, McGill University, Montréal, QC, H3T 1E2, Canada.
| | - Ivan Topisirovic
- Gerald Bronfman Department of Oncology, Montréal, QC, H3A 1A3, Canada; Department of Biochemistry, Montréal, QC, H3A 1A3, Canada; Department of Experimental Medicine McGill University, Montréal, QC, H3A 1A3, Canada; Lady Davis Institute, SMBD JGH, McGill University, Montréal, QC, H3T 1E2, Canada
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13
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Cho HY, Kim S, Jeon YH. Fragment-based methods for the discovery of inhibitors modulating lysyl-tRNA synthetase and laminin receptor interaction. Methods 2017; 113:56-63. [PMID: 27789335 DOI: 10.1016/j.ymeth.2016.10.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 10/14/2016] [Accepted: 10/20/2016] [Indexed: 10/20/2022] Open
Abstract
Lysyl-tRNA synthetase (KRS) is an enzyme that conjugates lysine to its cognate tRNAs in the process of protein synthesis. In addition to its catalytic function, KRS binds to the 67-kDa laminin receptor (LR) on the cell membrane and facilitates cell migration and metastasis. Modulation of this interaction by small-molecule inhibitors can be exploited to suppress cancer metastasis. In this study, we present fragment-based methods for the identification of inhibitors and monitoring protein-protein interactions between KRS and LR. First, we identified the amino acid residues, located on the KRS anticodon-binding domain, which interact with the C-terminal extension of the LR. One-dimensional (1D) relaxation-edited nuclear magnetic resonance spectroscopy (NMR) and competition experiments were designed and optimized to screen the fragment library. For screening using two-dimensional (2D) NMR, we identified the indicative signals in the KRS anticodon-binding domain and selected inhibitors that bind to KRS and compete with LR at the KRS-LR binding interface. These methods may offer an efficient approach for the discovery of anti-metastatic drugs.
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Affiliation(s)
- Hye Young Cho
- College of Pharmacy, Korea University, Sejong 30019, Republic of Korea
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea.
| | - Young Ho Jeon
- College of Pharmacy, Korea University, Sejong 30019, Republic of Korea.
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14
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Abstract
Aminoacyl-tRNA synthetases (AARSs) are essential enzymes that specifically aminoacylate one tRNA molecule by the cognate amino acid. They are a family of twenty enzymes, one for each amino acid. By coupling an amino acid to a specific RNA triplet, the anticodon, they are responsible for interpretation of the genetic code. In addition to this translational, canonical role, several aminoacyl-tRNA synthetases also fulfill nontranslational, moonlighting functions. In mammals, nine synthetases, those specific for amino acids Arg, Asp, Gln, Glu, Ile, Leu, Lys, Met and Pro, associate into a multi-aminoacyl-tRNA synthetase complex, an association which is believed to play a key role in the cellular organization of translation, but also in the regulation of the translational and nontranslational functions of these enzymes. Because the balance between their alternative functions rests on the assembly and disassembly of this supramolecular entity, it is essential to get precise insight into the structural organization of this complex. The high-resolution 3D-structure of the native particle, with a molecular weight of about 1.5 MDa, is not yet known. Low-resolution structures of the multi-aminoacyl-tRNA synthetase complex, as determined by cryo-EM or SAXS, have been reported. High-resolution data have been reported for individual enzymes of the complex, or for small subcomplexes. This review aims to present a critical view of our present knowledge of the aminoacyl-tRNA synthetase complex in 3D. These preliminary data shed some light on the mechanisms responsible for the balance between the translational and nontranslational functions of some of its components.
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Affiliation(s)
- Marc Mirande
- Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 1 avenue de la Terrasse, 91190, Gif-sur-Yvette, Paris, France.
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15
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Young HJ, Lee JW, Kim S. Function of membranous lysyl-tRNA synthetase and its implication for tumorigenesis. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2016; 1864:1707-1713. [PMID: 27663887 DOI: 10.1016/j.bbapap.2016.09.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Revised: 08/28/2016] [Accepted: 09/19/2016] [Indexed: 12/26/2022]
Abstract
Aminoacyl-tRNA synthetases (ARSs) are essential enzymes that conjugate specific amino acids to their cognate tRNAs for protein synthesis. Besides their catalytic activity, recent studies have uncovered many additional functions of these enzymes through their interactions with diverse cellular factors. Among human ARSs, cytosolic lysyl-tRNA synthetase (KRS) is often highly expressed in cancer cells and tissues, and facilitates cancer cell migration and invasion through the interaction with the 67kDa laminin receptor on the plasma membrane. Specific modulation of this interaction by small molecule inhibitors has revealed a new way to control metastasis. Here, we summarize the pro-metastatic functions of KRS and their patho-physiological implications.
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Affiliation(s)
- Ho Jeon Young
- College of Pharmacy, Korea University, Sejong 30019, Republic of Korea; Medicinal Bioconvergence Research Center, Seoul National University, Seoul 08826, Republic of Korea
| | - Jung Weon Lee
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea.
| | - Sunghoon Kim
- Medicinal Bioconvergence Research Center, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Seoul 08826, Republic of Korea
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16
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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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17
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Park BS, Jo HW, Jung J. Expression profile of aminoacyl-tRNA synthetases in dorsal root ganglion neurons after peripheral nerve injury. J Mol Histol 2014; 46:115-22. [PMID: 25467976 DOI: 10.1007/s10735-014-9601-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 11/26/2014] [Indexed: 12/15/2022]
Abstract
Aminoacyl-tRNA synthetases (AminoARSs) are essential enzymes involved in acylating tRNA with amino acids. In addition to the typical functions of AminoARSs, various non-canonical functions have been reported, such as involvement in cellular regulatory processes and signal transduction. Here, to explore the cellular changes in sensory neurons after nerve injury, we evaluated AARS mRNA expression in rat dorsal root ganglia (DRG) neurons using AminoARS-specific primers. Of 20 AminoARSs, we found that expression of lysyl-tRNA synthetase (KARS) and glutaminyl-tRNA synthetase (QARS) was decreased in the DRG injured side. We observed decreased KARS and QARS expression in DRG neuronal cell bodies, but not in satellite cells. Therefore, we suggest the possibility that KARS and QARS may act as signaling molecules to transfer abnormal sensory signals to the spinal dorsal horn after peripheral nerve damage. Therefore, KARS and QARS may represent powerful pharmaceutical targets via control of their non-canonical functions.
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Affiliation(s)
- Byung Sun Park
- Department of Anatomy and Neurobiology, School of Medicine, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 130-701, Republic of Korea
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18
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Abstract
When compared to other conserved housekeeping protein families, such as ribosomal proteins, during the evolution of higher eukaryotes, aminoacyl-tRNA synthetases (aaRSs) show an apparent high propensity to add new sequences, and especially new domains. The stepwise emergence of those new domains is consistent with their involvement in a broad range of biological functions beyond protein synthesis, and correlates with the increasing biological complexity of higher organisms. These new domains have been extensively characterized based on their evolutionary origins and their sequence, structural, and functional features. While some of the domains are uniquely found in aaRSs and may have originated from nucleic acid binding motifs, others are common domain modules mediating protein-protein interactions that play a critical role in the assembly of the multi-synthetase complex (MSC). Interestingly, the MSC has emerged from a miniature complex in yeast to a large stable complex in humans. The human MSC consists of nine aaRSs (LysRS, ArgRS, GlnRS, AspRS, MetRS, IleRS, LeuRS, GluProRS, and bifunctional aaRs) and three scaffold proteins (AIMP1/p43, AIMP2/p38, and AIMP3/p18), and has a molecular weight of 1.5 million Dalton. The MSC has been proposed to have a functional dualism: facilitating protein synthesis and serving as a reservoir of non-canonical functions associated with its synthetase and non-synthetase components. Importantly, domain additions and functional expansions are not limited to the components of the MSC and are found in almost all aaRS proteins. From a structural perspective, multi-functionalities are represented by multiple conformational states. In fact, alternative conformations of aaRSs have been generated by various mechanisms from proteolysis to alternative splicing and posttranslational modifications, as well as by disease-causing mutations. Therefore, the metamorphosis between different conformational states is connected to the activation and regulation of the novel functions of aaRSs in higher eukaryotes.
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Affiliation(s)
- Min Guo
- Department of Cancer Biology, The Scripps Research Institute, 130 Scripps Way, Jupiter, FL 33410, USA,
| | - Xiang-Lei Yang
- Department of Cancer Biology, The Scripps Research Institute, 10550 N. Torrey Pines Road, La Jolla, CA 92037, USA,
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19
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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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20
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Yao P, Poruri K, Martinis SA, Fox PL. Non-catalytic Regulation of Gene Expression by Aminoacyl-tRNA Synthetases. Top Curr Chem (Cham) 2013; 344:167-87. [DOI: 10.1007/128_2013_422] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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21
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Kim DG, Choi JW, Lee JY, Kim H, Oh YS, Lee JW, Tak YK, Song JM, Razin E, Yun S, Kim S. Interaction of two translational components, lysyl‐tRNA synthetase and p40/37LRP, in plasma membrane promotes laminin‐dependent cell migration. FASEB J 2012; 26:4142-59. [DOI: 10.1096/fj.12-207639] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Dae Gyu Kim
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- College of PharmacySeoul National UniversitySeoulKorea
| | - Jin Woo Choi
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- Wellman Center for PhotomedicineMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Jin Young Lee
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- College of PharmacySeoul National UniversitySeoulKorea
| | - Hyerim Kim
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
| | - Young Sun Oh
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
| | - Jung Weon Lee
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- College of PharmacySeoul National UniversitySeoulKorea
- World Class UniversityDepartment of Molecular Medicine and Biopharmaceutical SciencesSeoul National UniversitySeoulKorea
| | - Yu Kyung Tak
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- World Class UniversityDepartment of Molecular Medicine and Biopharmaceutical SciencesSeoul National UniversitySeoulKorea
| | - Joon Myong Song
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- World Class UniversityDepartment of Molecular Medicine and Biopharmaceutical SciencesSeoul National UniversitySeoulKorea
| | - Ehud Razin
- Department of Biochemistry and Molecular BiologyThe Hebrew University‐Hadassah Medical SchoolJerusalemIsrael
| | - Seok‐Hyun Yun
- Wellman Center for PhotomedicineMassachusetts General Hospital, Harvard Medical SchoolBostonMassachusettsUSA
| | - Sunghoon Kim
- Medicinal Bioconvergence Research CenterSeoul National UniversitySeoulKorea
- College of PharmacySeoul National UniversitySeoulKorea
- World Class UniversityDepartment of Molecular Medicine and Biopharmaceutical SciencesSeoul National UniversitySeoulKorea
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22
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D'Addabbo A, Palmieri O, Maglietta R, Latiano A, Mukherjee S, Annese V, Ancona N. Discovering genetic variants in Crohn's disease by exploring genomic regions enriched of weak association signals. Dig Liver Dis 2011; 43:623-31. [PMID: 21411385 DOI: 10.1016/j.dld.2011.02.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2010] [Revised: 01/28/2011] [Accepted: 02/08/2011] [Indexed: 12/11/2022]
Abstract
BACKGROUND A meta-analysis has re-analysed previous genome-wide association scanning definitively confirming eleven genes and further identifying 21 new loci. However, the identified genes/loci still explain only the minority of genetic predisposition of Crohn's disease. AIMS To identify genes weakly involved in disease predisposition by analysing chromosomal regions enriched of single nucleotide polymorphisms with modest statistical association. METHODS We utilized the WTCCC data set evaluating 1748 CD and 2938 controls. The identification of candidate genes/loci was performed by a two-step procedure: first of all chromosomal regions enriched of weak association signals were localized; subsequently, weak signals clustered in gene regions were identified. The statistical significance was assessed by non parametric permutation tests. RESULTS The cytoband enrichment analysis highlighted 44 regions (P≤0.05) enriched with single nucleotide polymorphisms significantly associated with the trait including 23 out of 31 previously confirmed and replicated genes. Importantly, we highlight further 20 novel chromosomal regions carrying approximately one hundred genes/loci with modest association. Amongst these we find compelling functional candidate genes such as MAPT, GRB2 and CREM, LCT, and IL12RB2. CONCLUSION Our study suggests a different statistical perspective to discover genes weakly associated with a given trait, although further confirmatory functional studies are needed.
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Affiliation(s)
- Annarita D'Addabbo
- Istituto di Studi sui Sistemi Intelligenti per l'Automazione - C.N.R., Bari, Italy
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23
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Structural context for mobilization of a human tRNA synthetase from its cytoplasmic complex. Proc Natl Acad Sci U S A 2011; 108:8239-44. [PMID: 21536907 DOI: 10.1073/pnas.1100224108] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Human lysyl-tRNA synthetase is bound to the multi-tRNA synthetase complex (MSC) that maintains and regulates the aminoacylation and nuclear functions of LysRS. The p38 scaffold protein binds LysRS to the MSC and, only with the appropriate cue, mobilizes LysRS for redirection to the nucleus to interact with the microphthalmia associated transcription factor (MITF). In recent work, an (α(2))(2) LysRS tetramer crystallized to yield a high-resolution structure and raised the question of how LysRS is arranged (dimer or tetramer) in the MSC to interact with p38. To understand the structural organization of the LysRS-p38 complex that regulates LysRS mobilization, we investigated the complex by use of small angle X-ray scattering and hydrogen-deuterium exchange with mass spectrometry in solution. The structure revealed a surprising α(2)β(1):β(1)α(2) organization in which a dimeric p38 scaffold holds two LysRS α(2) dimers in a parallel configuration. Each of the N-terminal 48 residues of p38 binds one LysRS dimer and, in so doing, brings two copies of the LysRS dimer into the MSC. The results suggest that this unique geometry, which reconfigures the LysRS tetramer from α(2):α(2) to α(2)β(1):β(1)α(2), is designed to control both retention and mobilization of LysRS from the MSC.
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Godinic-Mikulcic V, Jaric J, Hausmann CD, Ibba M, Weygand-Durasevic I. An archaeal tRNA-synthetase complex that enhances aminoacylation under extreme conditions. J Biol Chem 2010; 286:3396-404. [PMID: 21098026 DOI: 10.1074/jbc.m110.168526] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aminoacyl-tRNA synthetases (aaRSs) play an integral role in protein synthesis, functioning to attach the correct amino acid with its cognate tRNA molecule. AaRSs are known to associate into higher-order multi-aminoacyl-tRNA synthetase complexes (MSC) involved in archaeal and eukaryotic translation, although the precise biological role remains largely unknown. To gain further insights into archaeal MSCs, possible protein-protein interactions with the atypical Methanothermobacter thermautotrophicus seryl-tRNA synthetase (MtSerRS) were investigated. Yeast two-hybrid analysis revealed arginyl-tRNA synthetase (MtArgRS) as an interacting partner of MtSerRS. Surface plasmon resonance confirmed stable complex formation, with a dissociation constant (K(D)) of 250 nM. Formation of the MtSerRS·MtArgRS complex was further supported by the ability of GST-MtArgRS to co-purify MtSerRS and by coelution of the two enzymes during gel filtration chromatography. The MtSerRS·MtArgRS complex also contained tRNA(Arg), consistent with the existence of a stable ribonucleoprotein complex active in aminoacylation. Steady-state kinetic analyses revealed that addition of MtArgRS to MtSerRS led to an almost 4-fold increase in the catalytic efficiency of serine attachment to tRNA, but had no effect on the activity of MtArgRS. Further, the most pronounced improvements in the aminoacylation activity of MtSerRS induced by MtArgRS were observed under conditions of elevated temperature and osmolarity. These data indicate that formation of a complex between MtSerRS and MtArgRS provides a means by which methanogenic archaea can optimize an early step in translation under a wide range of extreme environmental conditions.
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Affiliation(s)
- Vlatka Godinic-Mikulcic
- Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, HR-10000 Zagreb, Croatia
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25
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Chen X, Ma JJ, Tan M, Yao P, Hu QH, Eriani G, Wang ED. Modular pathways for editing non-cognate amino acids by human cytoplasmic leucyl-tRNA synthetase. Nucleic Acids Res 2010; 39:235-47. [PMID: 20805241 PMCID: PMC3017609 DOI: 10.1093/nar/gkq763] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
To prevent potential errors in protein synthesis, some aminoacyl-transfer RNA (tRNA) synthetases have evolved editing mechanisms to hydrolyze misactivated amino acids (pre-transfer editing) or misacylated tRNAs (post-transfer editing). Class Ia leucyl-tRNA synthetase (LeuRS) may misactivate various natural and non-protein amino acids and then mischarge tRNA(Leu). It is known that the fidelity of prokaryotic LeuRS depends on multiple editing pathways to clear the incorrect intermediates and products in the every step of aminoacylation reaction. Here, we obtained human cytoplasmic LeuRS (hcLeuRS) and tRNA(Leu) (hctRNA(Leu)) with high activity from Escherichia coli overproducing strains to study the synthetic and editing properties of the enzyme. We revealed that hcLeuRS could adjust its editing strategy against different non-cognate amino acids. HcLeuRS edits norvaline predominantly by post-transfer editing; however, it uses mainly pre-transfer editing to edit α-amino butyrate, although both amino acids can be charged to tRNA(Leu). Post-transfer editing as a final checkpoint of the reaction was very important to prevent mis-incorporation in vitro. These results provide insight into the modular editing pathways created to prevent genetic code ambiguity by evolution.
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Affiliation(s)
- Xin Chen
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Graduate School of the Chinese Academy of Sciences, The Chinese Academy of Sciences, Shanghai 200031, China
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Pang YLJ, Martinis SA. A paradigm shift for the amino acid editing mechanism of human cytoplasmic leucyl-tRNA synthetase. Biochemistry 2009; 48:8958-64. [PMID: 19702327 DOI: 10.1021/bi901111y] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Leucyl-tRNA synthetase (LeuRS) has been identified as a target for a novel class of boron-containing small molecules that bind to its editing active site. When the 3' end of tRNA(Leu) binds to the editing active site, the boron cross-links to the cis-diols of its terminal ribose. The cross-linked RNA-protein complex blocks the overall aminoacylation activity of the enzyme. Similar to those of other LeuRSs, the human cytoplasmic enzyme (hscLeuRS) editing active site resides in a discrete domain called the connective polypeptide 1 domain (CP1), where mischarged tRNA binds for hydrolysis of the noncognate amino acid. The editing site of hscLeuRS includes a highly conserved threonine discriminator and universally conserved aspartic acid that were mutationally characterized. Substitution of the threonine residue to alanine uncoupled specificity as in other LeuRSs. However, the introduction of bulky residues into the amino acid binding pocket failed to block deacylation of tRNA, indicating that the architecture of the amino acid binding pocket is different compared to that of other characterized LeuRSs. In addition, mutation of the universally conserved aspartic acid abolished tRNA(Leu) deacylation. Surprisingly though, this editing-defective hscLeuRS maintained fidelity. It is possible that an alternate editing mechanism may have been activated upon failure of the post-transfer editing active site.
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Affiliation(s)
- Yan Ling Joy Pang
- Department of Biochemistry, University of Illinois, 419 Roger Adams Laboratory, Box B-4, 600 South Matthews Avenue, Urbana, Illinois 61801, USA
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Yannay-Cohen N, Carmi-Levy I, Kay G, Yang CM, Han JM, Kemeny DM, Kim S, Nechushtan H, Razin E. LysRS serves as a key signaling molecule in the immune response by regulating gene expression. Mol Cell 2009; 34:603-11. [PMID: 19524539 DOI: 10.1016/j.molcel.2009.05.019] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 12/31/2008] [Accepted: 05/26/2009] [Indexed: 11/28/2022]
Abstract
Lysyl-tRNA synthetase (LysRS) was found to produce diadenosine tetraphosphate (Ap(4)A) in vitro more than two decades ago. Here, we used LysRS silencing in mast cells in combination with transfected normal and mutated LysRS to demonstrate in vivo the critical role played by LysRS in the production of Ap(4)A in response to immunological challenge. Upon such challenge, LysRS was phosphorylated on serine 207 in a MAPK-dependent manner, released from the multisynthetase complex, and translocated into the nucleus. We previously demonstrated that LysRS forms a complex with MITF and its repressor Hint-1, which is released from the complex by its binding to Ap(4)A, enabling MITF to transcribe its target genes. Here, silencing LysRS led to reduced Ap(4)A production in immunologically activated cells, which resulted in a lower level of MITF inducible genes. Our data demonstrate that specific LysRS serine 207 phosphorylation regulates Ap(4)A production in immunologically stimulated mast cells, thus implying that LysRS is a key mediator in gene regulation.
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Affiliation(s)
- Nurit Yannay-Cohen
- Department of Biochemistry, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel
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28
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Anderson LL, Mao X, Scott BA, Crowder CM. Survival from hypoxia in C. elegans by inactivation of aminoacyl-tRNA synthetases. Science 2009; 323:630-3. [PMID: 19179530 DOI: 10.1126/science.1166175] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Hypoxia is important in a wide range of biological processes, such as animal hibernation and cell survival, and is particularly relevant in many diseases. The sensitivity of cells and organisms to hypoxic injury varies widely, but the molecular basis for this variation is incompletely understood. Using forward genetic screens in Caenorhabditis elegans, we isolated a hypoxia-resistant reduction-of-function mutant of rrt-1 that encodes an arginyl-transfer RNA (tRNA) synthetase, an enzyme essential for protein translation. Knockdown of rrt-1, and of most other genes encoding aminoacyl-tRNA synthetases, rescued animals from hypoxia-induced death, and the level of hypoxia resistance was inversely correlated with translation rate. The unfolded protein response was induced by hypoxia and was required for the hypoxia resistance of the reduction-of-function mutant of rrt-1. Thus, translational suppression produces hypoxia resistance, in part by reducing unfolded protein toxicity.
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Affiliation(s)
- Lori L Anderson
- Department of Anesthesiology, Washington University School of Medicine, St. Louis, MO 63110, USA
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29
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He R, Zu LD, Yao P, Chen X, Wang ED. Two non-redundant fragments in the N-terminal peptide of human cytosolic methionyl-tRNA synthetase were indispensable for the multi-synthetase complex incorporation and enzyme activity. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1794:347-54. [PMID: 19064003 DOI: 10.1016/j.bbapap.2008.11.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 11/03/2008] [Accepted: 11/04/2008] [Indexed: 10/21/2022]
Abstract
In human cytoplasm, nine aminoacyl-tRNA synthetases (aaRSs) and three protein factors form a multi-synthetase complex (MSC). Human cytosolic methionyl-tRNA synthetase (hcMetRS) is a component of the MSC. Sequence alignment revealed that hcMetRS has an N-terminal extension of 267 amino acid residues. This extension can be divided into three sub-domains: GST-like, GN, and GC sub-domains. The effect of each sub-domain in the N-terminal extension of hcMetRS on enzymatic activity and incorporation into the MSC was studied. The results of cellular assay showed that the GST-like sub-domain was responsible for the incorporation of hcMetRS into the MSC. The entire N-terminal extension of hcMetRS is indispensable for the enzymatic activity. Deletion mutagenesis revealed that a seven-amino acid motif within the sub-domain GC was important for the activity of amino acid activation. A conserved proline residue within the seven-amino acid motif was crucial, while the other six residues were moderately important for the amino acid activation activity. Thus, the last 15 residues of previously defined N-terminal extension of hcMetRS was a part of the catalytic domain; whereas the first 252 residues of hcMetRS constitute the N-terminal extended domain of hcMetRS. The formerly defined N-terminal extension of hcMetRS possesses two functions of two different domains.
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Affiliation(s)
- Ran He
- Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Shanghai 200031, China
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30
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Meerschaert K, Remue E, De Ganck A, Staes A, Boucherie C, Gevaert K, Vandekerckhove J, Kleiman L, Gettemans J. The tandem PDZ protein Syntenin interacts with the aminoacyl tRNA synthetase complex in a lysyl-tRNA synthetase-dependent manner. J Proteome Res 2008; 7:4962-73. [PMID: 18839981 DOI: 10.1021/pr800325u] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Syntenin-1 is a tandem PDZ protein that binds a diverse array of signaling molecules that are often associated with cell adhesion and intracellular trafficking. With the use of a MS-based functional proteomics approach, we identified several members of the aminoacyl-tRNA synthetase macromolecular (ARS) complex in a syntenin-1 pull down assay. Interaction of these proteins with syntenin-1 was confirmed by co-immunoprecipitation from cultured cells. We demonstrate a direct interaction of syntenin-1 with lysyl-tRNA synthetase (KRS), which contains a PDZ binding motif at its C-terminus. This motif is important for the interaction of the entire complex with syntenin-1. A point mutation in the PDZ2 domain of syntenin-1 abrogates interaction with KRS. As a result, other components of the ARS complex no longer co-immunoprecipitate with syntenin-1. We further show that syntenin-1 regulates KRS activity. These findings suggest that syntenin-1 is an adaptor modulating the activity of KRS.
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Affiliation(s)
- Kris Meerschaert
- Department of Medical Protein Research, VIB, B-9000 Ghent, Belgium
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31
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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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32
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Hausmann CD, Ibba M. Aminoacyl-tRNA synthetase complexes: molecular multitasking revealed. FEMS Microbiol Rev 2008; 32:705-21. [PMID: 18522650 DOI: 10.1111/j.1574-6976.2008.00119.x] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
The accurate synthesis of proteins, dictated by the corresponding nucleotide sequence encoded in mRNA, is essential for cell growth and survival. Central to this process are the aminoacyl-tRNA synthetases (aaRSs), which provide amino acid substrates for the growing polypeptide chain in the form of aminoacyl-tRNAs. The aaRSs are essential for coupling the correct amino acid and tRNA molecules, but are also known to associate in higher order complexes with proteins involved in processes beyond translation. Multiprotein complexes containing aaRSs are found in all three domains of life playing roles in splicing, apoptosis, viral assembly, and regulation of transcription and translation. An overview of the complexes aaRSs form in all domains of life is presented, demonstrating the extensive network of connections between the translational machinery and cellular components involved in a myriad of essential processes beyond protein synthesis.
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Affiliation(s)
- Corinne D Hausmann
- Department of Microbiology, The Ohio State University, Columbus, OH 43210-1292, USA
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33
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Kyriacou SV, Deutscher MP. An important role for the multienzyme aminoacyl-tRNA synthetase complex in mammalian translation and cell growth. Mol Cell 2008; 29:419-27. [PMID: 18313381 DOI: 10.1016/j.molcel.2007.11.038] [Citation(s) in RCA: 92] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2007] [Revised: 10/08/2007] [Accepted: 11/27/2007] [Indexed: 10/22/2022]
Abstract
In mammalian cells, aminoacyl-tRNA synthetases (aaRSs) are organized into a high-molecular-weight multisynthetase complex whose cellular function has remained a mystery. In this study, we have taken advantage of the fact that mammalian cells contain two forms of ArgRS, both products of the same gene, to investigate the complex's physiological role. The data indicate that the high-molecular-weight form of ArgRS, which is present exclusively as an integral component of the multisynthetase complex, is essential for normal protein synthesis and growth of CHO cells even when low-molecular-weight, free ArgRS is present and Arg-tRNA continues to be synthesized at close to wild-type levels. Based on these observations, we conclude that Arg-tRNA generated by the synthetase complex is a more efficient precursor for protein synthesis than Arg-tRNA generated by free ArgRS, exactly as would be predicted by the channeling model for mammalian translation.
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Affiliation(s)
- Sophia V Kyriacou
- Department of Biochemistry and Molecular Biology, University of Miami Miller School of Medicine, Miami, FL 33136, USA
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34
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Bottoni A, Vignali C, Piccin D, Tagliati F, Luchin A, Zatelli MC, Uberti ECD. Proteasomes and RARS modulate AIMP1/EMAP II secretion in human cancer cell lines. J Cell Physiol 2007; 212:293-7. [PMID: 17443684 DOI: 10.1002/jcp.21083] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The aminoacyl t-RNA synthetase interacting multifunctional protein (AIMP1) is the precursor of the multifunctional inflammatory cytokine endothelial monocyte-activating polypeptide II (EMAP II). We previously demonstrated that AIMP1 secretion by pituitary adenomas is inversely correlated with tumor diameter and with RARS expression, suggesting that a high amount of RARS associated with AIMP1 might prevent the secretion of the latter cytokine. In this study, we investigated the role of RARS in modulating the secretion of AIMP1 in HeLa and MCF7 cell lines and investigated the possible role of the multicatalytic protease in the cleavage of AIMP1 to generate EMAP II. Our data show that RARS over-expression impairs AIMP1 secretion by both HeLa and MCF7 cells. Moreover, proteasome inhibition impairs AIMP1 cleavage to produce EMAP II. These data indicate that RARS over-expression associates with a reduced AIMP1 secretion and that the multicatalytic protease is involved in the generation of the mature cytokine, EMAP II.
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Affiliation(s)
- Arianna Bottoni
- Section of Endocrinology, Department of Biomedical Sciences and Advanced Therapies, University of Ferrara, Ferrara, Italy
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35
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Antonellis A, Lee-Lin SQ, Wasterlain A, Leo P, Quezado M, Goldfarb LG, Myung K, Burgess S, Fischbeck KH, Green ED. Functional analyses of glycyl-tRNA synthetase mutations suggest a key role for tRNA-charging enzymes in peripheral axons. J Neurosci 2006; 26:10397-406. [PMID: 17035524 PMCID: PMC6674701 DOI: 10.1523/jneurosci.1671-06.2006] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Charcot-Marie-Tooth disease type 2D (CMT2D) and distal spinal muscular atrophy type V (dSMA-V) are axonal neuropathies characterized by a phenotype that is more severe in the upper extremities. We previously implicated mutations in the gene encoding glycyl-tRNA synthetase (GARS) as the cause of CMT2D and dSMA-V. GARS is a member of the family of aminoacyl-tRNA synthetases responsible for charging tRNA with cognate amino acids; GARS ligates glycine to tRNA(Gly). Here, we present functional analyses of disease-associated GARS mutations and show that there are not any significant mutation-associated changes in GARS expression levels; that the majority of identified GARS mutations modeled in yeast severely impair viability; and that, in most cases, mutant GARS protein mislocalizes in neuronal cells. Indeed, four of the five mutations studied show loss-of-function features in at least one assay, suggesting that tRNA-charging deficits play a role in disease pathogenesis. Finally, we detected endogenous GARS-associated granules in the neurite projections of cultured neurons and in the peripheral nerve axons of normal human tissue. These data are particularly important in light of the recent identification of CMT-associated mutations in another tRNA synthetase gene [YARS (tyrosyl-tRNA synthetase gene)]. Together, these findings suggest that tRNA-charging enzymes play a key role in maintaining peripheral axons.
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Affiliation(s)
| | | | | | - Paul Leo
- Genetic Disease Research Branch, and
| | | | | | - Kyungjae Myung
- Genetics and Molecular Biology Branch, National Human Genome Research Institute
| | | | - Kenneth H. Fischbeck
- Neurogenetics Branch, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892
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36
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Ding Q, Markesbery WR, Chen Q, Li F, Keller JN. Ribosome dysfunction is an early event in Alzheimer's disease. J Neurosci 2005; 25:9171-5. [PMID: 16207876 PMCID: PMC6725754 DOI: 10.1523/jneurosci.3040-05.2005] [Citation(s) in RCA: 303] [Impact Index Per Article: 15.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Alzheimer's disease (AD) is a progressive and devastating disorder that is often preceded by mild cognitive impairment (MCI). In the present study, we report that in multiple cortical areas of MCI and AD subjects, there is a significant impairment in ribosome function that is not observed in the cerebellum of the same subjects. The impairment in ribosome function is associated with a decreased rate and capacity for protein synthesis, decreased ribosomal RNA and tRNA levels, and increased RNA oxidation. No alteration in the level of initiation factors was observed in the brain regions exhibiting impairments in protein synthesis. Together, these data indicate for the first time that impairments in protein synthesis may be one of the earliest neurochemical alterations in AD and directly demonstrate that the polyribosome complex is adversely affected early in the development of AD. These data have important implications for AD studies involving proteomics and studies analyzing proteolysis in AD, indicate that oxidative damage may contribute to decreased protein synthesis, and suggest a role for alterations in protein synthesis as a novel contributor to the onset and development of AD.
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Affiliation(s)
- Qunxing Ding
- Department of Anatomy and Neurobiology, University of Kentucky, Lexington, Kentucky 40536-0230, USA
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37
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Park SG, Ewalt KL, Kim S. Functional expansion of aminoacyl-tRNA synthetases and their interacting factors: new perspectives on housekeepers. Trends Biochem Sci 2005; 30:569-74. [PMID: 16125937 DOI: 10.1016/j.tibs.2005.08.004] [Citation(s) in RCA: 217] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2005] [Revised: 07/13/2005] [Accepted: 08/12/2005] [Indexed: 11/19/2022]
Abstract
Aminoacyl-tRNA synthetases (ARSs) are essential enzymes that join amino acids to tRNAs, thereby linking the genetic code to specific amino acids. Once considered a class of 'housekeeping' enzymes, ARSs are now known to participate in a wide variety of functions, including transcription, translation, splicing, inflammation, angiogenesis and apoptosis. Three nonenzymatic proteins--ARS-interacting multi-functional proteins (AIMPs)--associate with ARSs in a multi-synthetase complex of higher eukaryotes. Similarly to ARSs, AIMPs have novel functions unrelated to their support role in protein synthesis, acting as a cytokine to control angiogenesis, immune response and wound repair, and as a crucial regulator for cell proliferation and DNA repair. Evaluation of the functional roles of individual ARSs and AIMPs might help to elucidate why these proteins as a whole contribute such varied functions and interactions in complex systems.
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Affiliation(s)
- Sang Gyu Park
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, San 56-1, Shillim-dong, Kwanak-gu, Seoul 151-742, Korea
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38
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Jiang S, Wolfe CL, Warrington JA, Norcum MT. Three-dimensional reconstruction of the valyl-tRNA synthetase/elongation factor-1H complex and localization of the delta subunit. FEBS Lett 2005; 579:6049-54. [PMID: 16229838 DOI: 10.1016/j.febslet.2005.09.062] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2005] [Revised: 09/20/2005] [Accepted: 09/26/2005] [Indexed: 01/06/2023]
Abstract
Eukaryotic valyl-tRNA synthetase (ValRS) and the heavy form of elongation factor 1 (EF-1H) are isolated as a stable high molecular mass complex that catalyzes consecutive steps in protein biosynthesis--aminoacylation of tRNA and its transfer to elongation factor. Herein is the first three-dimensional structure of the particle as calculated from electron microscopic images of negatively stained samples of the human ValRS/EF-1H complex. The ca. 12 x 8 nm particle has two distinct domains and each appears to have twofold symmetry. Bound antibodies place two delta subunits near the particle's center. These data support a dimeric head-to-head arrangement of particle components.
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Affiliation(s)
- Shoulei Jiang
- Department of Biochemistry, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USA
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39
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Wolfe CL, Warrington JA, Treadwell L, Norcum MT. A three-dimensional working model of the multienzyme complex of aminoacyl-tRNA synthetases based on electron microscopic placements of tRNA and proteins. J Biol Chem 2005; 280:38870-8. [PMID: 16169847 DOI: 10.1074/jbc.m502759200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
It has become evident that the process of protein synthesis is performed by many cellular polypeptides acting in concert within the structural confines of protein complexes. In multicellular eukaryotes, one of these assemblies is a multienzyme complex composed of eight proteins that have aminoacyl-tRNA synthetase activities as well as three non-synthetase proteins (p43, p38, and p18) with diverse functions. This study uses electron microscopy and three-dimensional reconstruction to explore the arrangement of proteins and tRNA substrates within this "core" multisynthetase complex. Binding of unfractionated tRNA establishes that these molecules are widely distributed on the exterior of the structure. Binding of gold-labeled tRNA(Leu) places leucyl-tRNA synthetase and the bifunctional glutamyl-/prolyl-tRNA synthetase at the base of this asymmetric "V"-shaped particle. A stable cell line has been produced that incorporates hexahistidine-labeled p43 into the multisynthetase complex. Using a gold-labeled nickel-nitrilotriacetic acid probe, the polypeptides of the p43 dimer have been located along one face of the particle. The results of this and previous studies are combined into an initial three-dimensional working model of the multisynthetase complex. This is the first conceptualization of how the protein constituents and tRNA substrates are arrayed within the structural confines of this multiprotein assembly.
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Affiliation(s)
- Cindy L Wolfe
- Department of Biology, Tougaloo College, Tougaloo, Mississippi 39174, USA
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40
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Arango D, Laiho P, Kokko A, Alhopuro P, Sammalkorpi H, Salovaara R, Nicorici D, Hautaniemi S, Alazzouzi H, Mecklin JP, Järvinen H, Hemminki A, Astola J, Schwartz S, Aaltonen LA. Gene-expression profiling predicts recurrence in Dukes' C colorectal cancer. Gastroenterology 2005; 129:874-84. [PMID: 16143127 DOI: 10.1053/j.gastro.2005.06.066] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Accepted: 06/09/2005] [Indexed: 12/27/2022]
Abstract
BACKGROUND & AIMS Although approximately 50% of Dukes' C colorectal cancer patients are surgically cured, it is currently not possible to distinguish these patients from those at high risk of recurrence. The recent advent of routine adjuvant chemotherapy for these patients has greatly complicated the identification of new markers predicting the response to surgery, which is now reliant on archived materials. Microarray analysis allows fine tumor classification but cannot be used with paraffin-embedded archival samples. METHODS We used microarray analysis of a unique set of fresh-frozen tumor samples from Dukes' C patients who had surgery as the only form of treatment to identify molecular signatures that characterize tumors from patients with good and bad prognosis. RESULTS Unsupervised hierarchical clustering and a K-nearest neighbors-based classifier identified groups of patients with significantly different survival (P = .019 and P = .0001). Expression profiling outperformed previously reported genetic markers of prognosis such as TP53 and K-RAS mutational status and allelic imbalance in chromosome 18q, which were of limited prognostic power in this study. Functional categories significantly enriched in gene-expression differences included protein transport and folding. The prognostic potential of the RAS homologue RHOA, one of the most differentially expressed genes, was further investigated using immunohistochemistry and a tissue microarray containing 137 independent Dukes' C tumor samples. Reduced RHOA expression was associated with significantly shorter survival (P = .01). CONCLUSIONS This study shows that gene-expression profiling of surgical tumor samples can predict recurrence in Dukes' C patients. Therefore, this approach could be used to guide decisions concerning the clinical management of these patients.
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Affiliation(s)
- Diego Arango
- Department of Medical Genetics, Biomedicum Helsinki, University of Helsinki, Helsinki, Finland.
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41
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Wolfson A, Knight R. Occurrence of the aminoacyl-tRNA synthetases in high-molecular weight complexes correlates with the size of substrate amino acids. FEBS Lett 2005; 579:3467-72. [PMID: 15963508 DOI: 10.1016/j.febslet.2005.05.038] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2005] [Revised: 05/06/2005] [Accepted: 05/11/2005] [Indexed: 11/16/2022]
Abstract
One of the distinctive and mysterious features of mammalian aminoacyl-tRNA synthetases (AARSs) is the existence of stable high-molecular weight complexes containing 10 out of 20 AARSs. The composition and structure of these complexes are conserved among multicellular animals. No specific function associated with these structures has been found, and there is no evident rationale for a particular separation of AARSs in "complex-bound" and "free" forms. We have demonstrated a strong association between the occurrence of AARSs in the complexes and the volume of their substrate amino acids. The significance of this association is discussed in terms of the structural organization of translation in the living cell.
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Affiliation(s)
- Alexey Wolfson
- Department of Chemistry and Biochemistry, University of Colorado, UCB 215, Boulder, CO 80309, USA.
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42
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Ling C, Yao YN, Zheng YG, Wei H, Wang L, Wu XF, Wang ED. The C-terminal appended domain of human cytosolic leucyl-tRNA synthetase is indispensable in its interaction with arginyl-tRNA synthetase in the multi-tRNA synthetase complex. J Biol Chem 2005; 280:34755-63. [PMID: 16055448 DOI: 10.1074/jbc.m413511200] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Human cytosolic leucyl-tRNA synthetase is one component of a macromolecular aminoacyl-tRNA synthetase complex. This is unlike prokaryotic and lower eukaryotic LeuRSs that exist as free soluble enzymes. There is little known about it, since the purified enzyme has been unavailable. Herein, human cytosolic leucyl-tRNA synthetase was heterologously expressed in a baculovirus system and purified to homogeneity. The molecular mass (135 kDa) of the enzyme is close to the theoretical value derived from its cDNA. The kinetic constants of the enzyme for ATP, leucine, and tRNA(Leu) in the ATP-PP(i) exchange and tRNA leucylation reactions were determined, and the results showed that it is quite active as a free enzyme. Human cytosolic leucyl-tRNA synthetase expressed in human 293 T cells localizes predominantly to the cytosol. Additionally, it is found to have a long C-terminal extension that is absent from bacterial and yeast LeuRSs. A C-terminal 89-amino acid truncated human cytosolic leucyl-tRNA synthetase was constructed and purified, and the catalytic activities, thermal stability, and subcellular location were found to be almost identical to native enzyme. In vivo and in vitro experiments, however, show that the C-terminal extension of human cytosolic leucyl-tRNA synthetase is indispensable for its interaction with the N-terminal of human cytosolic arginyl-tRNA synthetase in the macromolecular complex. Our results also indicate that the two molecules interact with each other only through their appended domains.
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Affiliation(s)
- Chen Ling
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031
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43
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Praetorius-Ibba M, Rogers TE, Samson R, Kelman Z, Ibba M. Association between Archaeal prolyl- and leucyl-tRNA synthetases enhances tRNA(Pro) aminoacylation. J Biol Chem 2005; 280:26099-104. [PMID: 15917221 PMCID: PMC1242193 DOI: 10.1074/jbc.m503539200] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Aminoacyl-tRNA synthetase-containing complexes have been identified in different eukaryotes, and their existence has also been suggested in some Archaea. To investigate interactions involving aminoacyl-tRNA synthetases in Archaea, we undertook a yeast two-hybrid screen for interactions between Methanothermobacter thermautotrophicus proteins using prolyl-tRNA synthetase (ProRS) as the bait. Interacting proteins identified included components of methanogenesis, protein-modifying factors, and leucyl-tRNA synthetase (LeuRS). The association of ProRS with LeuRS was confirmed in vitro by native gel electrophoresis and size exclusion chromatography. Determination of the steady-state kinetics of tRNA(Pro) charging showed that the catalytic efficiency (k(cat)/K(m)) of ProRS increased 5-fold in the complex with LeuRS compared with the free enzyme, whereas the K(m) for proline was unchanged. No significant changes in the steady-state kinetics of LeuRS aminoacylation were observed upon the addition of ProRS. These findings indicate that ProRS and LeuRS associate in M. thermautotrophicus and suggest that this interaction contributes to translational fidelity by enhancing tRNA aminoacylation by ProRS.
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Affiliation(s)
- Mette Praetorius-Ibba
- Department of Microbiology, The Ohio State University, Columbus, Ohio 43210-1292, USA.
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44
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Park SG, Kim HJ, Min YH, Choi EC, Shin YK, Park BJ, Lee SW, Kim S. Human lysyl-tRNA synthetase is secreted to trigger proinflammatory response. Proc Natl Acad Sci U S A 2005; 102:6356-61. [PMID: 15851690 PMCID: PMC1088368 DOI: 10.1073/pnas.0500226102] [Citation(s) in RCA: 138] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2005] [Indexed: 01/09/2023] Open
Abstract
Although aminoacyl-tRNA synthetases (ARSs) are essential for protein synthesis, they also function as regulators and signaling molecules in diverse biological processes. Here, we screened 11 different human ARSs to identify the enzyme that is secreted as a signaling molecule. Among them, we found that lysyl-tRNA synthetase (KRS) was secreted from intact human cells, and its secretion was induced by TNF-alpha. The secreted KRS bound to macrophages and peripheral blood mononuclear cells to enhance the TNF-alpha production and their migration. The mitogen-activated protein kinases, extracellular signal-regulated kinase and p38 mitogen-activated protein kinase, and Galphai were determined to be involved in the signal transduction triggered by KRS. All of these activities demonstrate that human KRS may work as a previously uncharacterized signaling molecule, inducing immune response through the activation of monocyte/macrophages.
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Affiliation(s)
- Sang Gyu Park
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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Lee SW, Cho BH, Park SG, Kim S. Aminoacyl-tRNA synthetase complexes: beyond translation. J Cell Sci 2005; 117:3725-34. [PMID: 15286174 DOI: 10.1242/jcs.01342] [Citation(s) in RCA: 194] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Although aminoacyl-tRNA synthetases (ARSs) are housekeeping enzymes essential for protein synthesis, they can play non-catalytic roles in diverse biological processes. Some ARSs are capable of forming complexes with each other and additional proteins. This characteristic is most pronounced in mammals, which produce a macromolecular complex comprising nine different ARSs and three additional factors: p43, p38 and p18. We have been aware of the existence of this complex for a long time, but its structure and function have not been well understood. The only apparent distinction between the complex-forming ARSs and those that do not form complexes is their ability to interact with the three non-enzymatic factors. These factors are required not only for the catalytic activity and stability of the associated ARSs, such as isoleucyl-, methionyl-, and arginyl-tRNA synthetase, but also for diverse signal transduction pathways. They may thus have joined the ARS community to coordinate protein synthesis with other biological processes.
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Affiliation(s)
- Sang Won Lee
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, Seoul 151-742, Korea
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Park SG, Shin H, Shin YK, Lee Y, Choi EC, Park BJ, Kim S. The novel cytokine p43 stimulates dermal fibroblast proliferation and wound repair. THE AMERICAN JOURNAL OF PATHOLOGY 2005; 166:387-98. [PMID: 15681823 PMCID: PMC1602330 DOI: 10.1016/s0002-9440(10)62262-6] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The multifunctional cytokine p43 acts on endothelial and immune cells to control angiogenesis and inflammation. In this report, we describe an additional activity of p43 that specifically promotes fibroblast proliferation and wound repair. In skin wound regions from mice, tumor necrosis factor-alpha induced p43 expression and secretion from macrophages recruited to the site. p43 also promoted fibroblast proliferation through its 146-amino acid N-terminal domain as revealed by deletion mapping. This p43-induced fibroblast proliferation was mediated by extracellular signal-regulated kinase (Erk). Depletion of endogenous p43 in mice by gene disruption retarded wound repair, whereas exogenous supplementation of recombinant human p43 to the wound area stimulated dermal fibroblast proliferation, collagen production, and wound closure. Thus, we have identified a novel p43 activity involving the stimulation of fibroblast proliferation, which could be applied therapeutically to aid wound repair.
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Affiliation(s)
- Sang Gyu Park
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, San 56-1, Shillim-dong, Kwanak-gu, Seoul 151-742, Korea
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Park BJ, Kang JW, Lee SW, Choi SJ, Shin YK, Ahn YH, Choi YH, Choi D, Lee KS, Kim S. The haploinsufficient tumor suppressor p18 upregulates p53 via interactions with ATM/ATR. Cell 2005; 120:209-21. [PMID: 15680327 DOI: 10.1016/j.cell.2004.11.054] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2004] [Revised: 09/07/2004] [Accepted: 11/22/2004] [Indexed: 01/05/2023]
Abstract
p18 was first identified as a factor associated with a macromolecular tRNA synthetase complex. Here we describe the mouse p18 loss-of-function phenotype and a role for p18 in the DNA damage response. Inactivation of both p18 alleles caused embryonic lethality, while heterozygous mice showed high susceptibility to spontaneous tumors. p18 was induced and translocated to the nucleus in response to DNA damage. Expression of p18 resulted in elevated p53 levels, while p18 depletion blocked p53 induction. p18 directly interacted with ATM/ATR in response to DNA damage. The activity of ATM was dependent on the level of p18, suggesting the requirement of p18 for the activation of ATM. Low p18 expression was frequently observed in different human cancer cell lines and tissues. These results suggest that p18 is a haploinsufficient tumor suppressor and a key factor for ATM/ATR-mediated p53 activation.
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Affiliation(s)
- Bum-Joon Park
- National Creative Research Initiatives Center for ARS Network, College of Pharmacy, Seoul National University, Seoul 151-742, South Korea
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Sampath P, Mazumder B, Seshadri V, Gerber CA, Chavatte L, Kinter M, Ting SM, Dignam JD, Kim S, Driscoll DM, Fox PL. Noncanonical function of glutamyl-prolyl-tRNA synthetase: gene-specific silencing of translation. Cell 2004; 119:195-208. [PMID: 15479637 DOI: 10.1016/j.cell.2004.09.030] [Citation(s) in RCA: 208] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2004] [Revised: 08/21/2004] [Accepted: 09/10/2004] [Indexed: 10/26/2022]
Abstract
Aminoacyl tRNA synthetases (ARS) catalyze the ligation of amino acids to cognate tRNAs. Chordate ARSs have evolved distinctive features absent from ancestral forms, including compartmentalization in a multisynthetase complex (MSC), noncatalytic peptide appendages, and ancillary functions unrelated to aminoacylation. Here, we show that glutamyl-prolyl-tRNA synthetase (GluProRS), a bifunctional ARS of the MSC, has a regulated, noncanonical activity that blocks synthesis of a specific protein. GluProRS was identified as a component of the interferon (IFN)-gamma-activated inhibitor of translation (GAIT) complex by RNA affinity chromatography using the ceruloplasmin (Cp) GAIT element as ligand. In response to IFN-gamma, GluProRS is phosphorylated and released from the MSC, binds the Cp 3'-untranslated region in an mRNP containing three additional proteins, and silences Cp mRNA translation. Thus, GluProRS has divergent functions in protein synthesis: in the MSC, its aminoacylation activity supports global translation, but translocation of GluProRS to an inflammation-responsive mRNP causes gene-specific translational silencing.
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Affiliation(s)
- Prabha Sampath
- Department of Cell Biology, The Lerner Research Institute, The Cleveland Clinic Foundation, 9500 Euclid Avenue, Cleveland, OH 44195, USA
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