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Li ZH, Zhou XL. Eukaryotic AlaX provides multiple checkpoints for quality and quantity of aminoacyl-tRNAs in translation. Nucleic Acids Res 2024; 52:7825-7842. [PMID: 38869066 PMCID: PMC11260482 DOI: 10.1093/nar/gkae486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Accepted: 05/27/2024] [Indexed: 06/14/2024] Open
Abstract
Translational fidelity relies critically on correct aminoacyl-tRNA supply. The trans-editing factor AlaX predominantly hydrolyzes Ser-tRNAAla, functioning as a third sieve of alanyl-tRNA synthetase (AlaRS). Despite extensive studies in bacteria and archaea, the mechanism of trans-editing in mammals remains largely unknown. Here, we show that human AlaX (hAlaX), which is exclusively distributed in the cytoplasm, is an active trans-editing factor with strict Ser-specificity. In vitro, both hAlaX and yeast AlaX (ScAlaX) were capable of hydrolyzing nearly all Ser-mischarged cytoplasmic and mitochondrial tRNAs; and robustly edited cognate Ser-charged cytoplasmic and mitochondrial tRNASers. In vivo or cell-based studies revealed that loss of ScAlaX or hAlaX readily induced Ala- and Thr-to-Ser misincorporation. Overexpression of hAlaX impeded the decoding efficiency of consecutive Ser codons, implying its regulatory role in Ser codon decoding. Remarkably, yeast cells with ScAlaX deletion responded differently to translation inhibitor treatment, with a gain in geneticin resistance, but sensitivity to cycloheximide, both of which were rescued by editing-capable ScAlaX, alanyl- or threonyl-tRNA synthetase. Altogether, our results demonstrated the previously undescribed editing peculiarities of eukaryotic AlaXs, which provide multiple checkpoints to maintain the speed and fidelity of genetic decoding.
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Affiliation(s)
- Zi-Han Li
- Key Laboratory of RNA Innovation, Science and Engineering, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
| | - Xiao-Long Zhou
- Key Laboratory of RNA Innovation, Science and Engineering, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China
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2
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Correia I, Oliveira C, Reis A, Guimarães AR, Aveiro S, Domingues P, Bezerra AR, Vitorino R, Moura G, Santos MAS. A proteogenomic pipeline for the analysis of protein biosynthesis errors in the human pathogen Candida albicans. Mol Cell Proteomics 2024:100818. [PMID: 39047911 DOI: 10.1016/j.mcpro.2024.100818] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 03/20/2024] [Accepted: 07/19/2024] [Indexed: 07/27/2024] Open
Abstract
Candida albicans is a diploid pathogen known for its ability to live as a commensal fungus in healthy individuals, but causing both superficial infections and disseminated candidiasis in immunocompromised patients where it is associated with high morbidity and mortality. Its success in colonizing the human host is attributed to a wide range of virulence traits that modulate interactions between the host and the pathogen, such as optimal growth rate at 37 ºC, the ability to switch between yeast and hyphal forms and a remarkable genomic and phenotypic plasticity. A fascinating aspect of its biology is a prominent heterogeneous proteome that arises from frequent genomic rearrangements, high allelic variation, and high levels of amino acid misincorporations in proteins. This leads to increased morphological and physiological phenotypic diversity of high adaptive potential, but the scope of such protein mistranslation is poorly understood due to technical difficulties in detecting and quantifying amino acid misincorporation events in complex protein samples. We have developed and optimized mass spectrometry and bioinformatics pipelines capable of identifying rare amino acid misincorporation events at the proteome level. We have also analysed the proteomic profile of an engineered C. albicans strain that exhibits high level of leucine misincorporation at protein CUG sites and employed an in vivo quantitative gain-of-function fluorescence reporter system to validate our LC-MS/MS data. C. albicans misincorporates amino acids above the background level at protein sites of diverse codons, particularly at CUG, confirming our previous data on the quantification of leucine incorporation at single CUG sites of recombinant reporter proteins, but increasing misincorporation of Leucine at these sites does not alter the translational fidelity of the other codons. These findings indicate that the C. albicans statistical proteome exceeds prior estimates, suggesting that its highly plastic phenome may also be modulated by environmental factors due to translational ambiguity.
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Affiliation(s)
- Inês Correia
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal.
| | - Carla Oliveira
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Andreia Reis
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Ana Rita Guimarães
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Susana Aveiro
- Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Pedro Domingues
- Department of Chemistry, University of Aveiro, Aveiro, Portugal
| | - Ana Rita Bezerra
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Rui Vitorino
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Gabriela Moura
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal
| | - Manuel A S Santos
- Institute of Biomedicine (iBiMED) and Department of Medical Sciences (DCM), University of Aveiro, Aveiro, Portugal; Multidisciplinary Institute of Ageing (MIA-Portugal), University of Coimbra, Coimbra, Portugal.
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3
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Yuan C, Li Z, Luo X, Huang P, Guo L, Lu M, Xia J, Xiao Y, Zhou XL, Chen M. Mammalian trans-editing factor ProX is able to deacylate tRNA Thr mischarged with alanine. Int J Biol Macromol 2023; 253:127121. [PMID: 37778588 DOI: 10.1016/j.ijbiomac.2023.127121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 08/16/2023] [Accepted: 09/26/2023] [Indexed: 10/03/2023]
Abstract
The precise coupling of tRNAs with their cognate amino acids, known as tRNA aminoacylation, is a stringently regulated process that governs translation fidelity. To ensure fidelity, organisms deploy multiple layers of editing mechanisms to correct mischarged tRNAs. Prior investigations have unveiled the propensity of eukaryotic AlaRS to erroneously attach alanine onto tRNACys and tRNAThr featuring the G4:U69 base pair. In light of this, and given ProXp-ala's capacity in deacylating Ala-tRNAPro, we embarked on exploring whether this trans-editing factor could extend its corrective function to encompass these mischarged tRNAs. Our in vitro deacylation assays demonstrate that murine ProXp-ala (mProXp-ala) is able to efficiently hydrolyze Ala-tRNAThr, while Ala-tRNACys remains unaffected. Subsequently, we determined the first structure of eukaryotic ProXp-ala, revealing a dynamic helix α2 involved in substrate binding. By integrating molecular dynamics simulations and biochemical assays, we pinpointed the pivotal interactions between mProXp-ala and Ala-tRNA, wherein the basic regions of mProXp-ala as well as the C3-G70 plays essential role in recognition. These observations collectively provide a cogent rationale for mProXp-ala's deacylation proficiency against Ala-tRNAThr. Our findings offer valuable insights into the translation quality control within higher eukaryotic organisms, where the fidelity of translation is safeguarded by the multi-functionality of extensively documented proteins.
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Affiliation(s)
- Chen Yuan
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China; Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Zihan Li
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Xinyu Luo
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Pingping Huang
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China; Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Lijie Guo
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China; Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Meiling Lu
- Department of Biochemistry, School of Life Science and Technology, China Pharmaceutical University, Nanjing 210009, China
| | - Jie Xia
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines, Institute of Materia Medica, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100050, China
| | - Yibei Xiao
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China; Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China; Chongqing Innovation Institute of China Pharmaceutical University, Chongqing 401135, China.
| | - Xiao-Long Zhou
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai 200031, China; Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou 310024, China.
| | - Meirong Chen
- State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 210009, China; Department of Pharmacology, School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China.
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4
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Zheng WQ, Zhang JH, Li ZH, Liu X, Zhang Y, Huang S, Li J, Zhou B, Eriani G, Wang ED, Zhou XL. Mammalian mitochondrial translation infidelity leads to oxidative stress-induced cell cycle arrest and cardiomyopathy. Proc Natl Acad Sci U S A 2023; 120:e2309714120. [PMID: 37669377 PMCID: PMC10500172 DOI: 10.1073/pnas.2309714120] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 08/08/2023] [Indexed: 09/07/2023] Open
Abstract
Proofreading (editing) of mischarged tRNAs by cytoplasmic aminoacyl-tRNA synthetases (aaRSs), whose impairment causes neurodegeneration and cardiac diseases, is of high significance for protein homeostasis. However, whether mitochondrial translation needs fidelity and the significance of editing by mitochondrial aaRSs have been unclear. Here, we show that mammalian cells critically depended on the editing of mitochondrial threonyl-tRNA synthetase (mtThrRS, encoded by Tars2), disruption of which accumulated Ser-tRNAThr and generated a large abundance of Thr-to-Ser misincorporated peptides in vivo. Such infidelity impaired mitochondrial translation and oxidative phosphorylation, causing oxidative stress and cell cycle arrest in the G0/G1 phase. Notably, reactive oxygen species (ROS) scavenging by N-acetylcysteine attenuated this abnormal cell proliferation. A mouse model of heart-specific defective mtThrRS editing was established. Increased ROS levels, blocked cardiomyocyte proliferation, contractile dysfunction, dilated cardiomyopathy, and cardiac fibrosis were observed. Our results elucidate that mitochondria critically require a high level of translational accuracy at Thr codons and highlight the cellular dysfunctions and imbalance in tissue homeostasis caused by mitochondrial mistranslation.
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Affiliation(s)
- Wen-Qiang Zheng
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai201210, China
| | - Jian-Hui Zhang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou310024, China
| | - Zi-Han Li
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
| | - Xiuxiu Liu
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
| | - Yong Zhang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
| | - Shuo Huang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai201210, China
| | - Jinsong Li
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou310024, China
| | - Bin Zhou
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou310024, China
| | - Gilbert Eriani
- Architecture et Réactivité de l’ARN, Institut de Biologie Moléculaire et Cellulaire du CNRS, Université de Strasbourg, Strasbourg67084, France
| | - En-Duo Wang
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- School of Life Science and Technology, ShanghaiTech University, Shanghai201210, China
| | - Xiao-Long Zhou
- Key Laboratory of RNA Science and Engineering, State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai200031, China
- Key Laboratory of Systems Health Science of Zhejiang Province, School of Life Science, Hangzhou Institute for Advanced Study, University of Chinese Academy of Sciences, Hangzhou310024, China
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5
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Bezerra AR, Oliveira C, Correia I, Guimarães AR, Sousa G, Carvalho MJ, Moura G, Santos MAS. The role of non-standard translation in Candida albicans pathogenesis. FEMS Yeast Res 2021; 21:6280978. [PMID: 34021562 PMCID: PMC8178436 DOI: 10.1093/femsyr/foab032] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Accepted: 05/20/2021] [Indexed: 12/22/2022] Open
Abstract
Candida albicans typically resides in the human gastrointestinal tract and mucosal membranes as a commensal organism. To adapt and cope with the host immune system, it has evolved a variety of mechanisms of adaptation such as stress-induced mutagenesis and epigenetic regulation. Niche-specific patterns of gene expression also allow the fungus to fine-tune its response to specific microenvironments in the host and switch from harmless commensal to invasive pathogen. Proteome plasticity produced by CUG ambiguity, on the other hand is emerging as a new layer of complexity in C. albicans adaptation, pathogenesis, and drug resistance. Such proteome plasticity is the result of a genetic code alteration where the leucine CUG codon is translated mainly as serine (97%), but maintains some level of leucine (3%) assignment. In this review, we dissect the link between C. albicans non-standard CUG translation, proteome plasticity, host adaptation and pathogenesis. We discuss published work showing how this pathogen uses the fidelity of protein synthesis to spawn novel virulence traits.
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Affiliation(s)
- Ana Rita Bezerra
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Carla Oliveira
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Inês Correia
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Ana Rita Guimarães
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Gonçalo Sousa
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Maria João Carvalho
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Gabriela Moura
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Manuel A S Santos
- Department of Medical Sciences, Institute of Biomedicine - iBiMED, University of Aveiro, 3810-193 Aveiro, Portugal
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6
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Gamper H, Hou YM. A Label-Free Assay for Aminoacylation of tRNA. Genes (Basel) 2020; 11:genes11101173. [PMID: 33036365 PMCID: PMC7601589 DOI: 10.3390/genes11101173] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 09/28/2020] [Accepted: 10/01/2020] [Indexed: 12/16/2022] Open
Abstract
Aminoacylation of tRNA generates an aminoacyl-tRNA (aa-tRNA) that is active for protein synthesis on the ribosome. Quantification of aminoacylation of tRNA is critical to understand the mechanism of specificity and the flux of the aa-tRNA into the protein synthesis machinery, which determines the rate of cell growth. Traditional assays for the quantification of tRNA aminoacylation involve radioactivity, either with a radioactive amino acid or with a [3′-32P]-labeled tRNA. We describe here a label-free assay that monitors aminoacylation by biotinylation-streptavidin (SA) conjugation to the α-amine or the α-imine of the aminoacyl group on the aa-tRNA. The conjugated aa-tRNA product is readily separated from the unreacted tRNA by a denaturing polyacrylamide gel, allowing for quantitative measurement of aminoacylation. This label-free assay is applicable to a wide range of amino acids and tRNA sequences and to both classes of aminoacylation. It is more sensitive and robust than the assay with a radioactive amino acid and has the potential to explore a wider range of tRNA than the assay with a [3′-32P]-labeled tRNA. This label-free assay reports kinetic parameters of aminoacylation quantitatively similar to those reported by using a radioactive amino acid, suggesting its broad applicability to research relevant to human health and disease.
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7
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Wang Y, Zhou JB, Zeng QY, Wu S, Xue MQ, Fang P, Wang ED, Zhou XL. Hearing impairment-associated KARS mutations lead to defects in aminoacylation of both cytoplasmic and mitochondrial tRNA Lys. SCIENCE CHINA-LIFE SCIENCES 2020; 63:1227-1239. [PMID: 32189241 DOI: 10.1007/s11427-019-1619-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Accepted: 01/03/2020] [Indexed: 01/20/2023]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are ubiquitously expressed, essential enzymes, synthesizing aminoacyl-tRNAs for protein synthesis. Functional defects of aaRSs frequently cause various human disorders. Human KARS encodes both cytosolic and mitochondrial lysyl-tRNA synthetases (LysRSs). Previously, two mutations (c.1129G>A and c.517T>C) were identified that led to hearing impairment; however, the underlying biochemical mechanism is unclear. In the present study, we found that the two mutations have no impact on the incorporation of LysRS into the multiple-synthetase complex in the cytosol, but affect the cytosolic LysRS level, its tertiary structure, and cytosolic tRNA aminoacylation in vitro. As for mitochondrial translation, the two mutations have little effect on the steady-state level, mitochondrial targeting, and tRNA binding affinity of mitochondrial LysRS. However, they exhibit striking differences in charging mitochondrial tRNALys, with the c.517T>C mutant being completely deficient in vitro and in vivo. We constructed two yeast genetic models, which are powerful tools to test the in vivo aminoacylation activity of KARS mutations at both the cytosolic and mitochondrial levels. Overall, our data provided biochemical insights into the potentially molecular pathological mechanism of KARS c.1129G>A and c.517T>C mutations and provided yeast genetic bases to investigate other KARS mutations in the future.
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Affiliation(s)
- Yong Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China.,School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China
| | - Jing-Bo Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Qi-Yu Zeng
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Siqi Wu
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Mei-Qin Xue
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China
| | - Pengfei Fang
- State Key Laboratory of Bioorganic and Natural Products Chemistry, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China. .,School of Life Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, 200031, China.
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8
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Hilander T, Zhou XL, Konovalova S, Zhang FP, Euro L, Chilov D, Poutanen M, Chihade J, Wang ED, Tyynismaa H. Editing activity for eliminating mischarged tRNAs is essential in mammalian mitochondria. Nucleic Acids Res 2019; 46:849-860. [PMID: 29228266 PMCID: PMC5778596 DOI: 10.1093/nar/gkx1231] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 11/30/2017] [Indexed: 02/06/2023] Open
Abstract
Accuracy of protein synthesis is enabled by the selection of amino acids for tRNA charging by aminoacyl-tRNA synthetases (ARSs), and further enhanced by the proofreading functions of some of these enzymes for eliminating tRNAs mischarged with noncognate amino acids. Mouse models of editing-defective cytoplasmic alanyl-tRNA synthetase (AlaRS) have previously demonstrated the importance of proofreading for cytoplasmic protein synthesis, with embryonic lethal and progressive neurodegeneration phenotypes. Mammalian mitochondria import their own set of nuclear-encoded ARSs for translating critical polypeptides of the oxidative phosphorylation system, but the importance of editing by the mitochondrial ARSs for mitochondrial proteostasis has not been known. We demonstrate here that the human mitochondrial AlaRS is capable of editing mischarged tRNAs in vitro, and that loss of the proofreading activity causes embryonic lethality in mice. These results indicate that tRNA proofreading is essential in mammalian mitochondria, and cannot be overcome by other quality control mechanisms.
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Affiliation(s)
- Taru Hilander
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Svetlana Konovalova
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland
| | - Fu-Ping Zhang
- Institute of Biomedicine, Turku Center for Disease Modeling, University of Turku, 20520 Turku, Finland
| | - Liliya Euro
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland
| | - Dmitri Chilov
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland
| | - Matti Poutanen
- Institute of Biomedicine, Turku Center for Disease Modeling, University of Turku, 20520 Turku, Finland
| | - Joseph Chihade
- Department of Chemistry, Carleton College, Northfield, MN 55057, USA
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, Shanghai 200031, China
| | - Henna Tyynismaa
- Research Programs Unit, Molecular Neurology, University of Helsinki, 00290 Helsinki, Finland.,Department of Medical and Clinical Genetics, University of Helsinki, 00290 Helsinki, Finland
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9
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Chen Y, Ruan ZR, Wang Y, Huang Q, Xue MQ, Zhou XL, Wang ED. A threonyl-tRNA synthetase-like protein has tRNA aminoacylation and editing activities. Nucleic Acids Res 2019; 46:3643-3656. [PMID: 29579307 PMCID: PMC5909460 DOI: 10.1093/nar/gky211] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2017] [Accepted: 03/13/2018] [Indexed: 01/22/2023] Open
Abstract
TARS and TARS2 encode cytoplasmic and mitochondrial threonyl-tRNA synthetases (ThrRSs) in mammals, respectively. Interestingly, in higher eukaryotes, a third gene, TARSL2, encodes a ThrRS-like protein (ThrRS-L), which is highly homologous to cytoplasmic ThrRS but with a different N-terminal extension (N-extension). Whether ThrRS-L has canonical functions is unknown. In this work, we studied the organ expression pattern, cellular localization, canonical aminoacylation and editing activities of mouse ThrRS-L (mThrRS-L). Tarsl2 is ubiquitously but unevenly expressed in mouse tissues. Different from mouse cytoplasmic ThrRS (mThrRS), mThrRS-L is located in both the cytoplasm and nucleus; the nuclear distribution is mediated via a nuclear localization sequence at its C-terminus. Native mThrRS-L enriched from HEK293T cells was active in aminoacylation and editing. To investigate the in vitro catalytic properties of mThrRS-L accurately, we replaced the N-extension of mThrRS-L with that of mThrRS. The chimeric protein (mThrRS-L-NT) has amino acid activation, aminoacylation and editing activities. We compared the activities and cross-species tRNA recognition between mThrRS-L-NT and mThrRS. Despite having a similar aminoacylation activity, mThrRS-L-NT and mThrRS exhibit differences in tRNA recognition and editing capacity. Our results provided the first analysis of the aminoacylation and editing activities of ThrRS-L, and improved our understanding of Tarsl2.
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Affiliation(s)
- Yun Chen
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China
| | - Zhi-Rong Ruan
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China
| | - Yong Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai, China
| | - Qian Huang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China
| | - Mei-Qin Xue
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai, China.,School of Life Science and Technology, ShanghaiTech University, 100 Haike Road, Shanghai, China
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10
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Liang Z, Yu X, Zhong W. Peptide Sequence Influence on the Differentiation of Valine and Norvaline by Hot Electron Capture Dissociation. Anal Chem 2019; 91:4381-4387. [PMID: 30786210 DOI: 10.1021/acs.analchem.8b04808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Isomeric amino acid residues such as valine (Val) and norvaline (Nva) are common in recombinant proteins. The mis-incorporation of Nva for leucine (Leu) causes heterogeneity and in some cases even toxicity. Previous studies have shown that hot electron capture dissociation (HECD) is able to differentiate Val from Nva by producing diagnostic w ions on custom designed synthetic model peptides. To broaden the utilization of HECD in proteomic studies and to define the critical structural features, a thorough investigation was performed on representative peptides including specifically designed synthetic peptides as well as biological peptides bearing tryptic digest-like features and peptides with post-translational modifications. Experimental evidence confirmed that the formation of a w ion is directly dependent upon the presence of the corresponding z ion. The results suggested that a charge carrier residue at the C-terminus is promoting the formation of diagnostic w ions for Nva. Thus, peptides resulting from trypsin digestion, with arginine (Arg) or lysine (Lys) at the C-terminus, can be analyzed using the HECD method. Post-translational modification (PTM) such as phosphorylation did not prevent the generation of the requisite side chain fragmentation w ions. These results suggest the general applicability of HECD for unambiguous identification of Val and Nva especially in structure characterization of therapeutic proteins.
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Affiliation(s)
- Zhidan Liang
- Analytical Research & Development, Merck Research Laboratories , Merck & Co., Inc. , Rahway , New Jersey 07065 , United States
| | - Xiang Yu
- Department of Pharmacokinetics, Pharmacodynamics, & Drug Metabolism (PPDM), Merck Research Laboratories , Merck & Co., Inc. , West Point , Pennsylvania 19486 , United States
| | - Wendy Zhong
- Analytical Research & Development, Merck Research Laboratories , Merck & Co., Inc. , Rahway , New Jersey 07065 , United States
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11
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Fraga JS, Sárkány Z, Silva A, Correia I, Pereira PJB, Macedo-Ribeiro S. Genetic code ambiguity modulates the activity of a C. albicans MAP kinase linked to cell wall remodeling. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2019; 1867:654-661. [PMID: 30797104 DOI: 10.1016/j.bbapap.2019.02.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Revised: 02/13/2019] [Accepted: 02/18/2019] [Indexed: 12/28/2022]
Abstract
The human fungal pathogen Candida albicans ambiguously decodes the universal leucine CUG codon predominantly as serine but also as leucine. C. albicans has a high capacity to survive and proliferate in adverse environments but the rate of leucine incorporation fluctuates in response to different stress conditions. C. albicans is adapted to tolerate this ambiguous translation through a mechanism that combines drastic decrease in CUG usage and reduction of CUG-encoded residues in conserved positions in the protein sequences. However, in a few proteins, the residues encoded by CUG codons are found in strictly conserved positions, suggesting that this genetic code alteration might have a functional impact. One such example is Cek1, a central signaling protein kinase that contains a single CUG-encoded residue at a conserved position, whose identity might regulate the correct flow of information across the MAPK cascade. Here we show that insertion of a leucine at the CUG-encoded position decreases the stability of Cek1, apparently without major structural alterations. In contrast, incorporation of a serine residue at the CUG position induces the autophosphorylation of the conserved tyrosine residue of the Cek1 231TEY233 motif, and increases its intrinsic kinase activity in vitro. These findings show that CUG ambiguity modulates the activity of Cek1, a key kinase directly linked to morphogenesis and virulence in C. albicans.
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Affiliation(s)
- Joana S Fraga
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal; ICBAS-Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, 4050-313 Porto, Portugal
| | - Zsuzsa Sárkány
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Alexandra Silva
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Inês Correia
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Pedro José Barbosa Pereira
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal
| | - Sandra Macedo-Ribeiro
- IBMC-Instituto de Biologia Molecular e Celular, Universidade do Porto, 4200-135 Porto, Portugal; Instituto de Investigação e Inovação em Saúde, Universidade do Porto, 4200-135 Porto, Portugal.
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12
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Sommerville EW, Zhou XL, Oláhová M, Jenkins J, Euro L, Konovalova S, Hilander T, Pyle A, He L, Habeebu S, Saunders C, Kelsey A, Morris AAM, McFarland R, Suomalainen A, Gorman GS, Wang ED, Thiffault I, Tyynismaa H, Taylor RW. Instability of the mitochondrial alanyl-tRNA synthetase underlies fatal infantile-onset cardiomyopathy. Hum Mol Genet 2019; 28:258-268. [PMID: 30285085 PMCID: PMC6321959 DOI: 10.1093/hmg/ddy294] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 08/02/2018] [Accepted: 08/07/2018] [Indexed: 11/14/2022] Open
Abstract
Recessively inherited variants in AARS2 (NM_020745.2) encoding mitochondrial alanyl-tRNA synthetase (mt-AlaRS) were first described in patients presenting with fatal infantile cardiomyopathy and multiple oxidative phosphorylation defects. To date, all described patients with AARS2-related fatal infantile cardiomyopathy are united by either a homozygous or compound heterozygous c.1774C>T (p.Arg592Trp) missense founder mutation that is absent in patients with other AARS2-related phenotypes. We describe the clinical, biochemical and molecular investigations of two unrelated boys presenting with fatal infantile cardiomyopathy, lactic acidosis and respiratory failure. Oxidative histochemistry showed cytochrome c oxidase-deficient fibres in skeletal and cardiac muscle. Biochemical studies showed markedly decreased activities of mitochondrial respiratory chain complexes I and IV with a mild decrease of complex III activity in skeletal and cardiac muscle. Using next-generation sequencing, we identified a c.1738C>T (p.Arg580Trp) AARS2 variant shared by both patients that was in trans with a loss-of-function heterozygous AARS2 variant; a c.1008dupT (p.Asp337*) nonsense variant or an intragenic deletion encompassing AARS2 exons 5-7. Interestingly, our patients did not harbour the p.Arg592Trp AARS2 founder mutation. In silico modelling of the p.Arg580Trp substitution suggested a deleterious impact on protein stability and folding. We confirmed markedly decreased mt-AlaRS protein levels in patient fibroblasts, skeletal and cardiac muscle, although mitochondrial protein synthesis defects were confined to skeletal and cardiac muscle. In vitro data showed that the p.Arg580Trp variant had a minimal effect on activation, aminoacylation or misaminoacylation activities relative to wild-type mt-AlaRS, demonstrating that instability of mt-AlaRS is the biological mechanism underlying the fatal cardiomyopathy phenotype in our patients.
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Affiliation(s)
- Ewen W Sommerville
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Xiao-Long Zhou
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Monika Oláhová
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Janda Jenkins
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO, USA
| | - Liliya Euro
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Svetlana Konovalova
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Taru Hilander
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Angela Pyle
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Langping He
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Sultan Habeebu
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO, USA
| | - Carol Saunders
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO, USA
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, MO, USA
- School of Medicine, University of Missouri Kansas City, Kansas City, MO , USA
| | - Anna Kelsey
- Institute of Human Development, University of Manchester, Manchester M13 9PL, UK; Willink Metabolic Unit, Genomic Medicine, Saint Mary’s Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester M13 9WL, UK
| | - Andrew A M Morris
- Institute of Human Development, University of Manchester, Manchester M13 9PL, UK; Willink Metabolic Unit, Genomic Medicine, Saint Mary’s Hospital, Manchester University Hospitals NHS Foundation Trust, Manchester M13 9WL, UK
| | - Robert McFarland
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - Anu Suomalainen
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
- Neuroscience Center, Helsinki Institute of Life Sciences, University of Helsinki, Helsinki Finland
- Department of Neurosciences, Helsinki University Hospital, Helsinki, Finland
| | - Gráinne S Gorman
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences, University of Chinese Academy of Sciences, Shanghai, China
| | - Isabelle Thiffault
- Center for Pediatric Genomic Medicine, Children's Mercy Hospital, Kansas City, MO, USA
- Department of Pathology and Laboratory Medicine, Children's Mercy Hospital, Kansas City, MO, USA
- School of Medicine, University of Missouri Kansas City, Kansas City, MO , USA
| | - Henna Tyynismaa
- Research Programs Unit, Molecular Neurology, University of Helsinki, Helsinki, Finland
| | - Robert W Taylor
- Wellcome Centre for Mitochondrial Research, Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, UK
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13
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Ji QQ, Fang ZP, Ye Q, Chi CW, Wang ED. Self-protective responses to norvaline-induced stress in a leucyl-tRNA synthetase editing-deficient yeast strain. Nucleic Acids Res 2017; 45:7367-7381. [PMID: 28575390 PMCID: PMC5499588 DOI: 10.1093/nar/gkx487] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 05/24/2017] [Indexed: 12/23/2022] Open
Abstract
The editing function of aminoacyl-tRNA synthetases (aaRSs) is indispensible for formation of the correct aminoacyl-tRNAs. Editing deficiency may lead to growth inhibition and the pathogenesis of various diseases. Herein, we confirmed that norvaline (Nva) but not isoleucine or valine is the major threat to the editing function of Saccharomyces cerevisiae leucyl-tRNA synthetase (ScLeuRS), both in vitro and in vivo. Nva could be misincorporated into the proteome of the LeuRS editing-deficient yeast strain (D419A/ScΔleuS), potentially resulting in dysfunctional protein folding and growth delay. Furthermore, the exploration of the Nva-induced intracellular stress response mechanism in D419A/ScΔleuS revealed that Hsp70 chaperones were markedly upregulated in response to the potential protein misfolding. Additionally, proline (Pro), glutamate (Glu) and glutamine (Gln), which may accumulate due to the conversion of Nva, collectively contributed to the reduction of reactive oxygen species (ROS) levels in Nva-treated D419A/ScΔleuS cells. In conclusion, our study highlights the significance of the editing function of LeuRS and provides clues for understanding the intracellular stress protective mechanisms that are triggered in aaRS editing-deficient organisms.
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Affiliation(s)
- Quan-Quan Ji
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China
| | - Zhi-Peng Fang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China
| | - Qing Ye
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China
| | - Cheng-Wu Chi
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, CAS Center for Excellence in Molecular Cell Science, Shanghai Institute of Biochemistry and Cell Biology, Chinese Academy of Sciences; University of Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, P. R. China.,School of Life Science and Technology, Shanghai Tech University, 100 Haike Road, Shanghai 201210, P. R. China
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14
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Zhou XL, He LX, Yu LJ, Wang Y, Wang XJ, Wang ED, Yang T. Mutations inKARScause early-onset hearing loss and leukoencephalopathy: Potential pathogenic mechanism. Hum Mutat 2017; 38:1740-1750. [PMID: 28887846 DOI: 10.1002/humu.23335] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Revised: 08/07/2017] [Accepted: 09/03/2017] [Indexed: 12/23/2022]
Affiliation(s)
- Xiao-Long Zhou
- State Key Laboratory of Molecular Biology; CAS Center for Excellence in Molecular Cell Science; Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of Sciences; University of Chinese Academy of Sciences; Shanghai China
| | - Long-Xia He
- Department of Otolaryngology-Head and Neck Surgery; Shanghai Ninth People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
- Department of Otorhinolaryngology-Head and Neck Surgery; Chengdu Integrated TCM & Western Medicine Hospital; Sichuan Province China
| | - Li-Jia Yu
- Department of Neurology; Xinhua Hospital; Shanghai Jiao Tong University School of Medicine; Shanghai China
| | - Yong Wang
- School of Life Science and Technology; Shanghai Tech University; Shanghai China
| | - Xi-Jin Wang
- Department of Neurology; Xinhua Hospital; Shanghai Jiao Tong University School of Medicine; Shanghai China
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology; CAS Center for Excellence in Molecular Cell Science; Shanghai Institute of Biochemistry and Cell Biology Chinese Academy of Sciences; University of Chinese Academy of Sciences; Shanghai China
- School of Life Science and Technology; Shanghai Tech University; Shanghai China
| | - Tao Yang
- Department of Otolaryngology-Head and Neck Surgery; Shanghai Ninth People's Hospital; Shanghai Jiaotong University School of Medicine; Shanghai China
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15
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Genomic, Transcriptomic, and Proteomic Analysis Provide Insights Into the Cold Adaptation Mechanism of the Obligate Psychrophilic Fungus Mrakia psychrophila. G3-GENES GENOMES GENETICS 2016; 6:3603-3613. [PMID: 27633791 PMCID: PMC5100859 DOI: 10.1534/g3.116.033308] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Mrakia psychrophila is an obligate psychrophilic fungus. The cold adaptation mechanism of psychrophilic fungi remains unknown. Comparative genomics analysis indicated that M. psychrophila had a specific codon usage preference, especially for codons of Gly and Arg and its major facilitator superfamily (MFS) transporter gene family was expanded. Transcriptomic analysis revealed that genes involved in ribosome and energy metabolism were upregulated at 4°, while genes involved in unfolded protein binding, protein processing in the endoplasmic reticulum, proteasome, spliceosome, and mRNA surveillance were upregulated at 20°. In addition, genes related to unfolded protein binding were alternatively spliced. Consistent with other psychrophiles, desaturase and glycerol 3-phosphate dehydrogenase, which are involved in biosynthesis of unsaturated fatty acid and glycerol respectively, were upregulated at 4°. Cold adaptation of M. psychrophila is mediated by synthesizing unsaturated fatty acids to maintain membrane fluidity and accumulating glycerol as a cryoprotectant. The proteomic analysis indicated that the correlations between the dynamic patterns between transcript level changes and protein level changes for some pathways were positive at 4°, but negative at 20°. The death of M. psychrophila above 20° might be caused by an unfolded protein response.
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16
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Zhou XL, Chen Y, Fang ZP, Ruan ZR, Wang Y, Liu RJ, Xue MQ, Wang ED. Translational Quality Control by Bacterial Threonyl-tRNA Synthetases. J Biol Chem 2016; 291:21208-21221. [PMID: 27542414 DOI: 10.1074/jbc.m116.740472] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Indexed: 11/06/2022] Open
Abstract
Translational fidelity mediated by aminoacyl-tRNA synthetases ensures the generation of the correct aminoacyl-tRNAs, which is critical for most species. Threonyl-tRNA synthetase (ThrRS) contains multiple domains, including an N2 editing domain. Of the ThrRS domains, N1 is the last to be assigned a function. Here, we found that ThrRSs from Mycoplasma species exhibit differences in their domain composition and editing active sites compared with the canonical ThrRSs. The Mycoplasma mobile ThrRS, the first example of a ThrRS naturally lacking the N1 domain, displays efficient post-transfer editing activity. In contrast, the Mycoplasma capricolum ThrRS, which harbors an N1 domain and a degenerate N2 domain, is editing-defective. Only editing-capable ThrRSs were able to support the growth of a yeast thrS deletion strain (ScΔthrS), thus suggesting that ScΔthrS is an excellent tool for studying the in vivo editing of introduced bacterial ThrRSs. On the basis of the presence or absence of an N1 domain, we further revealed the crucial importance of the only absolutely conserved residue within the N1 domain in regulating editing by mediating an N1-N2 domain interaction in Escherichia coli ThrRS. Our results reveal the translational quality control of various ThrRSs and the role of the N1 domain in translational fidelity.
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Affiliation(s)
- Xiao-Long Zhou
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - Yun Chen
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - Zhi-Peng Fang
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - Zhi-Rong Ruan
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - Yong Wang
- the School of Life Science and Technology, ShanghaiTech University, 200031 Shanghai, China
| | - Ru-Juan Liu
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - Mei-Qin Xue
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and
| | - En-Duo Wang
- From the State Key Laboratory of Molecular Biology, Chinese Academy of Sciences Center for Excellence in Molecular Cell Science, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 200031 Shanghai, China and the School of Life Science and Technology, ShanghaiTech University, 200031 Shanghai, China
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17
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Ji QQ, Fang ZP, Ye Q, Ruan ZR, Zhou XL, Wang ED. C-terminal Domain of Leucyl-tRNA Synthetase from Pathogenic Candida albicans Recognizes both tRNASer and tRNALeu. J Biol Chem 2015; 291:3613-25. [PMID: 26677220 DOI: 10.1074/jbc.m115.699777] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Indexed: 11/06/2022] Open
Abstract
Leucyl-tRNA synthetase (LeuRS) is a multidomain enzyme that catalyzes Leu-tRNA(Leu) formation and is classified into bacterial and archaeal/eukaryotic types with significant diversity in the C-terminal domain (CTD). CTDs of both bacterial and archaeal LeuRSs have been reported to recognize tRNA(Leu) through different modes of interaction. In the human pathogen Candida albicans, the cytoplasmic LeuRS (CaLeuRS) is distinguished by its capacity to recognize a uniquely evolved chimeric tRNA(Ser) (CatRNA(Ser)(CAG)) in addition to its cognate CatRNA(Leu), leading to CUG codon reassignment. Our previous study showed that eukaryotic but not archaeal LeuRSs recognize this peculiar tRNA(Ser), suggesting the significance of their highly divergent CTDs in tRNA(Ser) recognition. The results of this study provided the first evidence of the indispensable function of the CTD of eukaryotic LeuRS in recognizing non-cognate CatRNA(Ser) and cognate CatRNA(Leu). Three lysine residues were identified as involved in mediating enzyme-tRNA interaction in the leucylation process: mutation of all three sites totally ablated the leucylation activity. The importance of the three lysine residues was further verified by gel mobility shift assays and complementation of a yeast leuS gene knock-out strain.
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Affiliation(s)
- Quan-Quan Ji
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and
| | - Zhi-Peng Fang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and
| | - Qing Ye
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and
| | - Zhi-Rong Ruan
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and
| | - Xiao-Long Zhou
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and
| | - En-Duo Wang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, 200031 Shanghai, China and School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, 200031 Shanghai, China
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18
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Lei HY, Zhou XL, Ruan ZR, Sun WC, Eriani G, Wang ED. Calpain Cleaves Most Components in the Multiple Aminoacyl-tRNA Synthetase Complex and Affects Their Functions. J Biol Chem 2015; 290:26314-27. [PMID: 26324710 PMCID: PMC4646279 DOI: 10.1074/jbc.m115.681999] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Indexed: 12/13/2022] Open
Abstract
Nine aminoacyl-tRNA synthetases (aaRSs) and three scaffold proteins form a super multiple aminoacyl-tRNA synthetase complex (MSC) in the human cytoplasm. Domains that have been added progressively to MSC components during evolution are linked by unstructured flexible peptides, producing an elongated and multiarmed MSC structure that is easily attacked by proteases in vivo. A yeast two-hybrid screen for proteins interacting with LeuRS, a representative MSC member, identified calpain 2, a calcium-activated neutral cysteine protease. Calpain 2 and calpain 1 could partially hydrolyze most MSC components to generate specific fragments that resembled those reported previously. The cleavage sites of calpain in ArgRS, GlnRS, and p43 were precisely mapped. After cleavage, their N-terminal regions were removed. Sixty-three amino acid residues were removed from the N terminus of ArgRS to form ArgRSΔN63; GlnRS formed GlnRSΔN198, and p43 formed p43ΔN106. GlnRSΔN198 had a much weaker affinity for its substrates, tRNA(Gln) and glutamine. p43ΔN106 was the same as the previously reported p43-derived apoptosis-released factor. The formation of p43ΔN106 by calpain depended on Ca(2+) and could be specifically inhibited by calpeptin and by RNAi of the regulatory subunit of calpain in vivo. These results showed, for the first time, that calpain plays an essential role in dissociating the MSC and might regulate the canonical and non-canonical functions of certain components of the MSC.
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Affiliation(s)
- Hui-Yan Lei
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Xiao-Long Zhou
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Zhi-Rong Ruan
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China, University of Chinese Academy of Sciences, Beijing 100039, China
| | - Wei-Cheng Sun
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China, University of Chinese Academy of Sciences, Beijing 100039, China, The School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, Shanghai 200031, China, and
| | - Gilbert Eriani
- Architecture et Réactivité de l'ARN, Université de Strasbourg, UPR9002 CNRS, Institut de Biologie Moléculaire et Cellulaire, 15 rue René Descartes, 67084 Strasbourg Cedex, France
| | - En-Duo Wang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China, University of Chinese Academy of Sciences, Beijing 100039, China, The School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, Shanghai 200031, China, and
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19
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Ye Q, Wang M, Fang ZP, Ruan ZR, Ji QQ, Zhou XL, Wang ED. Degenerate connective polypeptide 1 (CP1) domain from human mitochondrial leucyl-tRNA synthetase. J Biol Chem 2015; 290:24391-402. [PMID: 26272616 DOI: 10.1074/jbc.m115.672824] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Indexed: 11/06/2022] Open
Abstract
The connective polypeptide 1 (CP1) editing domain of leucyl-tRNA synthetase (LeuRS) from various species either harbors a conserved active site to exclude tRNA mis-charging with noncognate amino acids or is evolutionarily truncated or lost because there is no requirement for high translational fidelity. However, human mitochondrial LeuRS (hmtLeuRS) contains a full-length but degenerate CP1 domain that has mutations in some residues important for post-transfer editing. The significance of such an inactive CP1 domain and a translational accuracy mechanism with different noncognate amino acids are not completely understood. Here, we identified the essential role of the evolutionarily divergent CP1 domain in facilitating hmtLeuRS's catalytic efficiency and endowing enzyme with resistance to AN2690, a broad-spectrum drug acting on LeuRSs. In addition, the canonical core of hmtLeuRS is not stringent for noncognate norvaline (Nva) and valine (Val). hmtLeuRS has a very weak tRNA-independent pre-transfer editing activity for Nva, which is insufficient to remove mis-activated Nva. Moreover, hmtLeuRS chimeras fused with a functional CP1 domain from LeuRSs of other species, regardless of origin, showed restored post-transfer editing activity and acquired fidelity during aminoacylation. This work offers a novel perspective on the role of the CP1 domain in optimizing aminoacylation efficiency.
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Affiliation(s)
- Qing Ye
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - Meng Wang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - Zhi-Peng Fang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - Zhi-Rong Ruan
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - Quan-Quan Ji
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - Xiao-Long Zhou
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and
| | - En-Duo Wang
- From the State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai and the School of Life Science and Technology, ShanghaiTech University, 319 Yue Yang Road, Shanghai 200031, China
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Sárkány Z, Silva A, Pereira PJB, Macedo-Ribeiro S. Ser or Leu: structural snapshots of mistranslation in Candida albicans. Front Mol Biosci 2014; 1:27. [PMID: 25988168 PMCID: PMC4428446 DOI: 10.3389/fmolb.2014.00027] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 12/04/2014] [Indexed: 11/29/2022] Open
Abstract
Candida albicans is a polymorphic opportunistic fungal pathogen normally residing as commensal on mucosal surfaces, skin and gastrointestinal and genitourinary tracts. However, in immunocompromised patients C. albicans can cause superficial mucosal infections or life-threatening disseminated candidemia. A change in physiological conditions triggers a cascade of molecular events leading to morphogenetic alterations and increased resistance to damage induced by host defenses. The complex biology of this human pathogen is reflected in its morphological plasticity and reinforced by the ability to ambiguously translate the universal leucine CUG codon predominantly as serine, but also as leucine. Mistranslation affects more than half of C. albicans proteome and it is widespread across many biological processes. A previous analysis of CTG-codon containing gene products in C. albicans suggested that codon ambiguity subtly shapes protein function and might have a pivotal role in signaling cascades associated with morphological changes and pathogenesis. In this review we further explore this hypothesis by highlighting the role of ambiguous decoding in macromolecular recognition of key effector proteins associated with the regulation of signal transduction cascades and the cell cycle, which are critical processes for C. albicans morphogenic plasticity under a variety of environmental conditions.
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Affiliation(s)
- Zsuzsa Sárkány
- Protein Crystallography Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto Porto, Portugal
| | - Alexandra Silva
- Protein Crystallography Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto Porto, Portugal
| | - Pedro J B Pereira
- Biomolecular Structure Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto Porto, Portugal
| | - Sandra Macedo-Ribeiro
- Protein Crystallography Group, IBMC - Instituto de Biologia Molecular e Celular, Universidade do Porto Porto, Portugal
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Fang ZP, Wang M, Ruan ZR, Tan M, Liu RJ, Zhou M, Zhou XL, Wang ED. Coexistence of bacterial leucyl-tRNA synthetases with archaeal tRNA binding domains that distinguish tRNA(Leu) in the archaeal mode. Nucleic Acids Res 2014; 42:5109-24. [PMID: 24500203 PMCID: PMC4005665 DOI: 10.1093/nar/gku108] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Leucyl-tRNA (transfer RNA) synthetase (LeuRS) is a multi-domain enzyme, which is divided into bacterial and archaeal/eukaryotic types. In general, one specific LeuRS, the domains of which are of the same type, exists in a single cell compartment. However, some species, such as the haloalkaliphile Natrialba magadii, encode two cytoplasmic LeuRSs, NmLeuRS1 and NmLeuRS2, which are the first examples of naturally occurring chimeric enzymes with different domains of bacterial and archaeal types. Furthermore, N. magadii encodes typical archaeal tRNALeus. The tRNA recognition mode, aminoacylation and translational quality control activities of these two LeuRSs are interesting questions to be addressed. Herein, active NmLeuRS1 and NmLeuRS2 were successfully purified after gene expression in Escherichia coli. Under the optimized aminoacylation conditions, we discovered that they distinguished cognate NmtRNALeu in the archaeal mode, whereas the N-terminal region was of the bacterial type. However, NmLeuRS1 exhibited much higher aminoacylation and editing activity than NmLeuRS2, suggesting that NmLeuRS1 is more likely to generate Leu-tRNALeu for protein biosynthesis. Moreover, using NmLeuRS1 as a model, we demonstrated misactivation of several non-cognate amino acids, and accuracy of protein synthesis was maintained mainly via post-transfer editing. This comprehensive study of the NmLeuRS/tRNALeu system provides a detailed understanding of the coevolution of aminoacyl-tRNA synthetases and tRNA.
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Affiliation(s)
- Zhi-Peng Fang
- Center for RNA Research, State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, 320 Yue Yang Road, Shanghai 200031, China
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