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Bhowal P, Roy B, Ganguli S, Igloi GL, Banerjee R. Elucidating the structure-function attributes of a trypanosomal arginyl-tRNA synthetase. Mol Biochem Parasitol 2023; 256:111597. [PMID: 37852416 DOI: 10.1016/j.molbiopara.2023.111597] [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: 08/06/2023] [Revised: 09/20/2023] [Accepted: 10/10/2023] [Indexed: 10/20/2023]
Abstract
Aminoacyl-tRNA synthetases (aaRSs) are fundamental components of the protein translation machinery. In light of their pivotal role in protein synthesis and structural divergence among species, they have always been considered potential targets for the development of antimicrobial compounds. Arginyl-tRNA synthetase from Trypanosoma cruzi (TcArgRS), the parasite responsible for causing Chagas Disease, contains a 100-amino acid insertion that was found to be completely absent in the human counterpart of similar length, as ascertained from multiple sequence alignment results. Thus, we were prompted to perform a preliminary characterization of TcArgRS using biophysical, biochemical, and bioinformatics tools. We expressed the protein in E. coli and validated its in-vitro enzymatic activity. Additionally, analysis of DTNB kinetics, Circular dichroism (CD) spectra, and ligand-binding studies using intrinsic tryptophan fluorescence measurements aided us to understand some structural features in the absence of available crystal structures. Our study indicates that TcArgRS can discriminate between L-arginine and its analogues. Among the many tested substrates, only L-canavanine and L-thioarginine, a synthetic arginine analogue exhibited notable activation. The binding of various substrates was also determined using in silico methods. This study may provide a viable foundation for studying small compounds that can be targeted against TcArgRS.
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Affiliation(s)
- Pratyasha Bhowal
- Department of Biotechnology and Dr. B. C. Guha Centre for Genetic Engineering and Biotechnology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700 019, India
| | - Bappaditya Roy
- Department of Microbiology, The Ohio State University, 318 West 12th Avenue, Columbus, OH 43210, USA; Center for RNA Biology, The Ohio State University, Columbus, OH 43210, USA
| | - Sayak Ganguli
- Post Graduate Department of Biotechnology, St. Xavier's College (Autonomous), 30, Park Street, Mullick Bazar, Kolkata 700 016, India.
| | - Gabor L Igloi
- Institute of Biology III, University of Freiburg, Schänzlestr 1, D-79104 Freiburg, Germany
| | - Rajat Banerjee
- Department of Biotechnology and Dr. B. C. Guha Centre for Genetic Engineering and Biotechnology, University of Calcutta, 35, Ballygunge Circular Road, Kolkata 700 019, India.
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The mutagenic and antimutagenic activity of Sutherlandia frutescens extracts and marker compounds. Altern Ther Health Med 2018; 18:93. [PMID: 29544492 PMCID: PMC5856389 DOI: 10.1186/s12906-018-2159-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2016] [Accepted: 03/07/2018] [Indexed: 12/31/2022]
Abstract
BACKGROUND Sutherlandia frutescens (L.) R. Br is endemic to Southern Africa where it has been traditionally used for cancer and diabetes. In recent times it has been marketed for its reputed (but not proven) anticancer, antidiabetic and anti-HIV properties. Little is known about the mutagenic and antimutagenic potential of extracts and common marker compounds of Sutherlandia frutescens. Therefore this study aimed to investigate the putative efficacy and possible long-term adverse effects of using this herb. METHODS Ethylacetate (EA) and 50% Methanol (MeOH) extracts were screened for mutagenic and antimutagenic activity using the Ames assay utilising TA97a, TA98, TA100 and TA102 in the presence and absence of metabolic activation. Four compounds, L-arginine, L-canavanine, GABA and D-pinitol known to occur in sutherlandia were also included. The total polyphenolic content of the both extracts was determined using the Folin-Ciocalteau method and FRAP and ABTS were used to determine the anti-oxidant potential of the extracts. RESULTS The extracts and the standards did not show any cytotoxicity except in TA97a. The EA extract exhibited antimutagenicity against all the bacterial strains at all concentrations tested. The MeOH extract showed both pro-mutagenic and antimutagenic activities with 2-acetamidofluorene and aflatoxin B1 in the presence of metabolic activation of TA98 and TA100, respectively. All compounds, except L-canavanine exhibited antimutagenic activity against all strains. L-canavanine, on the other hand showed co-mutagenicity with 9-aminoacridine on TA97a, at all test concentrations. The extracts and pure compounds exhibited their antimutagenic activity in a dose response manner. L-arginine and GABA showed an some antimutagenic response. EA extract had three times the total phenolic content (12.56 μg GE / mg) observed in the MeOH extract. There was correlation between total phenolic content, antioxidant potential and antimutagenicity. CONCLUSION Both extracts exhibited a protective effect, with the EA extract exhibiting greater potency. L-canavanine acted as a co-mutagen in a dose response manner without metabolic activation. It is suggested that the EA extract be priotized for future development work as it showed a better risk profile and activity.
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Nurcahyanti AD, Wink M. L-Canavanine potentiates the cytotoxicity of doxorubicin and cisplatin in arginine deprived human cancer cells. PeerJ 2016; 4:e1542. [PMID: 26839743 PMCID: PMC4734457 DOI: 10.7717/peerj.1542] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2015] [Accepted: 12/07/2015] [Indexed: 12/13/2022] Open
Abstract
The non-protein amino acid L-canavanine (L-CAV), an antimetabolite of L-arginine (L-ARG), can alter the 3D conformation of proteins when incorporated into a protein instead of L-ARG. L-CAV inhibits the proliferation of some tumour cells. The deprivation of L-ARG in the culture medium enhances the response of cells to L-CAV. This study aimed to investigate the interaction of L-CAV in combination with the chemotherapeutic drugs, doxorubicin (DOX) or cisplatin (CIS), in cancer cells, especially in the absence of L-ARG. A combination method based on the median-effect principle and mass-action law was used. The following cancer cells were employed: HeLa and Caco-2 cells, overexpressing argininosuccinate synthase (ASS), pancreatic cells (MIA PaCa-2 and BxPC-3) and hepatocellular carcinoma cells (Hep G2 and SK-HEP-1), with down-regulated ASS. When constant and non-constant ratios of L-CAV were combined with DOX and CIS, a synergistic potentiation of cytotoxicity was recorded. Cells expressing high levels of ASS were more sensitive to the treatment as compared to the cells with reduced ASS levels. Overall, this study may provide a new approach to targeting some cancer cells with L-CAV in combination with DNA-targeting drugs such as DOX and CIS, especially those cells which overexpress ASS, such as human cervical and colorectal carcinoma cells.
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Affiliation(s)
- Agustina Dr Nurcahyanti
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University , Heidelberg , Germany
| | - Michael Wink
- Institute of Pharmacy and Molecular Biotechnology, Heidelberg University , Heidelberg , Germany
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Bobak Y, Kurlishchuk Y, Vynnytska-Myronovska B, Grydzuk O, Shuvayeva G, Redowicz MJ, Kunz-Schughart LA, Stasyk O. Arginine deprivation induces endoplasmic reticulum stress in human solid cancer cells. Int J Biochem Cell Biol 2015; 70:29-38. [PMID: 26546743 DOI: 10.1016/j.biocel.2015.10.027] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 10/20/2015] [Accepted: 10/30/2015] [Indexed: 12/13/2022]
Abstract
Deprivation for the single amino acid arginine is a rapidly developing metabolic anticancer therapy, which allows growth control in a number of highly malignant tumors. Here we report that one of the responses of human solid cancer cells to arginine starvation is the induction of prolonged endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR). Systematic study of two colorectal carcinoma HCT-116 and HT29, glioblastoma U251 MG and ovarian carcinoma SKOV3 cell lines revealed, however, that the ER stress triggered by the absence of arginine does not result in massive apoptosis despite a profound upregulation of the proapoptotic gene CHOP. Instead, Akt- and MAPK-dependent pathways were activated which may counteract proapoptotic signaling. Treatment with DMSO as a disaggregating agent or with cycloheximide to block protein synthesis reduced ER stress evoked by arginine deprivation. On the other hand, ER stress and apoptosis induction in arginine-starved cells could be critically augmented by the arginine analog of plant origin canavanine, but not by the classic ER stress inducer tunicamycin. Our data suggest that canavanine treatment applied under the lack of arginine may enhance the efficacy of arginine deprivation-based anticancer therapy.
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Affiliation(s)
- Yaroslav Bobak
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine.
| | - Yuliya Kurlishchuk
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, TU Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology, Fetscherstr. 74, 01307 Dresden, Germany.
| | - Bozhena Vynnytska-Myronovska
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine; OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, TU Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology, Fetscherstr. 74, 01307 Dresden, Germany.
| | - Olesia Grydzuk
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine.
| | - Galyna Shuvayeva
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine.
| | - Maria J Redowicz
- Laboratory of Molecular Basis of Cell Motility, Nencki Institute of Experimental Biology, Polish Academy of Sciences, Pasteur Str. 3, 02-093 Warsaw, Poland.
| | - Leoni A Kunz-Schughart
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, TU Dresden and Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology, Fetscherstr. 74, 01307 Dresden, Germany; Department of Oncology, Old Road Campus Research Building, Roosevelt Drive, Oxford OX3 7DQ, UK.
| | - Oleh Stasyk
- Department of Cell Signaling, Institute of Cell Biology, National Academy of Sciences of Ukraine, Drahomanov Str. 14/16, 79005 Lviv, Ukraine.
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Ylikallio E, Konovalova S, Dhungana Y, Hilander T, Junna N, Partanen JV, Toppila JP, Auranen M, Tyynismaa H. Truncated HSPB1 causes axonal neuropathy and impairs tolerance to unfolded protein stress. BBA CLINICAL 2015; 3:233-42. [PMID: 26675522 PMCID: PMC4661565 DOI: 10.1016/j.bbacli.2015.03.002] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 02/28/2015] [Accepted: 03/03/2015] [Indexed: 11/26/2022]
Abstract
Background HSPB1 belongs to the family of small heat shock proteins (sHSP) that have importance in protection against unfolded protein stress, in cancer cells for escaping drug toxicity stress and in neurons for suppression of protein aggregates. sHSPs have a conserved α-crystalline domain (ACD), flanked by variable N- and C-termini, whose functions are not fully understood. Dominant missense variants in HSPB1, locating mostly to the ACD, have been linked to inherited neuropathy. Methods Patients underwent detailed clinical and neurophysiologic characterization. Disease causing variants were identified by exome or gene panel sequencing. Primary patient fibroblasts were used to investigate the effects of the dominant defective HSPB1 proteins. Results Frameshift variant predicting ablation of the entire C-terminus p.(Met169Cfs2*) of HSPB1 and a missense variant p.(Arg127Leu) were identified in patients with dominantly inherited motor-predominant axonal Charcot–Marie–Tooth neuropathy. We show that the truncated protein is stable and binds wild type HSPB1. Both mutations impaired the heat stress tolerance of the fibroblasts. This effect was particularly pronounced for the cells with the truncating variant, independent of heat-induced nuclear translocation and induction of global transcriptional heat response. Furthermore, the truncated HSPB1 increased cellular sensitivity to protein misfolding. Conclusion Our results suggest that truncation of the non-conserved C-terminus impairs the function of HSPB1 in cellular stress response. General significance sHSPs have important roles in prevention of protein aggregates that induce toxicity. We showed that C-terminal part of HSPB1 is critical for tolerance of unfolded protein stress, and when lacking causes axonal neuropathy in patients. C-terminal truncation of small heat shock protein HSPB1 causes neuropathy. Truncated HSPB1 is stable in patient fibroblasts and binds wild type HSPB1. C-terminus of HSPB1 is critical for tolerance to unfolded protein stress. Neuropathy may develop as a consequence of impaired cellular stress response.
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Key Words
- ACD, α-crystalline domain
- CADD, combined annotation dependent depletion
- CMT, Charcot–Marie–Tooth disease
- Charcot–Marie–Tooth neuropathy
- EMG, electromyography
- ENMG, electroneuromyography
- EVS, exome variant server
- HSPB1
- MUP, motor unit potential
- Protein misfolding
- QST, quantitative sensory testing
- SISu, Sequencing Initiative Suomi
- dHMN, distal hereditary motor neuropathy
- heat shock protein
- sHSP, small heat shock protein
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Affiliation(s)
- Emil Ylikallio
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland
| | - Svetlana Konovalova
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland
| | - Yogesh Dhungana
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland
| | - Taru Hilander
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland
| | - Nella Junna
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland
| | - Juhani V Partanen
- Department of Clinical Neurophysiology, Medical Imaging Center, Helsinki University Central Hospital, Finland
| | - Jussi P Toppila
- Department of Clinical Neurophysiology, Medical Imaging Center, Helsinki University Central Hospital, Finland
| | - Mari Auranen
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland ; Department of Neurology, Helsinki University Central Hospital, Helsinki 00290, Finland
| | - Henna Tyynismaa
- Research Programs Unit, Molecular Neurology, Biomedicum Helsinki, University of Helsinki, Helsinki 00290, Finland ; Department of Medical Genetics, Haartman Institute, University of Helsinki, Helsinki 00290, Finland
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Kim HS, Cha SY, Jo CH, Han A, Hwang KY. The crystal structure of arginyl-tRNA synthetase fromHomo sapiens. FEBS Lett 2014; 588:2328-34. [DOI: 10.1016/j.febslet.2014.05.027] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 05/12/2014] [Accepted: 05/12/2014] [Indexed: 10/25/2022]
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Ishida Y, Park JH, Mao L, Yamaguchi Y, Inouye M. Replacement of all arginine residues with canavanine in MazF-bs mRNA interferase changes its specificity. J Biol Chem 2013; 288:7564-7571. [PMID: 23378533 DOI: 10.1074/jbc.m112.434969] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Replacement of a specific amino acid residue in a protein with nonnatural analogues is highly challenging because of their cellular toxicity. We demonstrate for the first time the replacement of all arginine (Arg) residues in a protein with canavanine (Can), a toxic Arg analogue. All Arg residues in the 5-base specific (UACAU) mRNA interferase from Bacillus subtilis (MazF-bs(arg)) were replaced with Can by using the single-protein production system in Escherichia coli. The resulting MazF-bs(can) gained a 6-base recognition sequence, UACAUA, for RNA cleavage instead of the 5-base sequence, UACAU, for MazF-bs(arg). Mass spectrometry analysis confirmed that all Arg residues were replaced with Can. The present system offers a novel approach to create new functional proteins by replacing a specific amino acid in a protein with its analogues.
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Affiliation(s)
- Yojiro Ishida
- Department of Biochemistry, Robert Wood Johnson Medical School and Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854
| | - Jung-Ho Park
- Department of Biochemistry, Robert Wood Johnson Medical School and Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854
| | - Lili Mao
- Department of Biochemistry, Robert Wood Johnson Medical School and Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854
| | - Yoshihiro Yamaguchi
- Department of Biochemistry, Robert Wood Johnson Medical School and Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854
| | - Masayori Inouye
- Department of Biochemistry, Robert Wood Johnson Medical School and Center for Advanced Biotechnology and Medicine, Piscataway, New Jersey 08854.
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Dasuri K, Ebenezer PJ, Uranga RM, Gavilán E, Zhang L, Fernandez-Kim SOK, Bruce-Keller AJ, Keller JN. Amino acid analog toxicity in primary rat neuronal and astrocyte cultures: implications for protein misfolding and TDP-43 regulation. J Neurosci Res 2011; 89:1471-7. [PMID: 21608013 DOI: 10.1002/jnr.22677] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2011] [Revised: 03/20/2011] [Accepted: 04/03/2011] [Indexed: 12/13/2022]
Abstract
Amino acid analogs promote translational errors that result in aberrant protein synthesis and have been used to understand the effects of protein misfolding in a variety of physiological and pathological settings. TDP-43 is a protein that is linked to protein aggregation and toxicity in a variety of neurodegenerative diseases. This study exposed primary rat neurons and astrocyte cultures to established amino acid analogs (canavanine and azetidine-2-carboxylic acid) and showed that both cell types undergo a dose-dependent increase in toxicity, with neurons exhibiting a greater degree of toxicity compared with astrocytes. Neurons and astrocytes exhibited similar increases in ubiquitinated and oxidized protein following analog treatment. Analog treatment increased heat shock protein (Hsp) levels in both neurons and astrocytes. In neurons, and to a lesser extent astrocytes, the levels of TDP-43 increased in response to analog treatment. Taken together, these data indicate that neurons exhibit preferential toxicity and alterations in TDP-43 in response to increased protein misfolding compared with astrocytes.
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Affiliation(s)
- Kalavathi Dasuri
- Pennington Biomedical Research Center, Louisiana State University System, Baton Rouge, LA 70808-4124, USA
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Bence AK, Crooks PA. The Mechanism of l-Canavanine Cytotoxicity: Arginyl tRNA Synthetase as a Novel Target for Anticancer Drug Discovery. J Enzyme Inhib Med Chem 2008; 18:383-94. [PMID: 14692504 DOI: 10.1080/1475636031000152277] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
There is a clear need for agents with novel mechanisms of action to provide new therapeutic approaches for the treatment of pancreatic cancer. Owing to its structural similarity to L-arginine, L-canavanine, the beta-oxa-analog of L-arginine, is a substrate for arginyl tRNA synthetase and is incorporated into nascent proteins in place of L-arginine. Although L-arginine and L-canavanine are structurally similar, the oxyguanidino group of L-canavanine is significantly less basic than the guanidino group of L-arginine. Consequently, L-canavanyl proteins lack the capacity to form crucial ionic interactions, resulting in altered protein structure and function, which leads to cellular death. Since L-canavanine is selectively sequestered by the pancreas, it may be especially useful as an adjuvant therapy in the treatment of pancreatic cancer. This novel mechanism of cytotoxicity forms the basis for the anticancer activity of L-canavanine and thus, arginyl tRNA synthetase may represent a novel target for the development of such therapeutic agents.
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Affiliation(s)
- Aimee K Bence
- Division of Pharmaceutical Sciences, 800 Rose Street, College of Pharmacy, University of Kentucky, Lexington, KY 40536-0082, USA
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Akaogi J, Barker T, Kuroda Y, Nacionales DC, Yamasaki Y, Stevens BR, Reeves WH, Satoh M. Role of non-protein amino acid L-canavanine in autoimmunity. Autoimmun Rev 2005; 5:429-35. [PMID: 16890899 DOI: 10.1016/j.autrev.2005.12.004] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Association of SLE and alfalfa was first reported in a volunteer who developed lupus-like autoimmunity while ingesting alfalfa seed for a hypercholesterolemia study. This was corroborated with studies in monkeys fed with alfalfa sprout that developed SLE. Re-challenge with L-canavanine relapsed the disease. Arginine homologue L-canavanine, present in alfalfa, was suspected as a cause. L-canavanine can be charged by arginyl tRNA synthetase to replace L-arginine during protein synthesis. Aberrant canavanyl proteins have disrupted structure and functions. Induction or exacerbation of SLE by alfalfa tablets reported in a few cases remains controversial. Epidemiological studies on the relationship between alfalfa and SLE are sparse. In mice, NZB/W F1, NZB, and DBA/2 mice fed with L-canavanine show exacerbation/triggering of the SLE, however, BALB/c studies were negative. L-canavanine incorporation may be more efficient in the presence of inflammation or other conditions that can cause arginine deficiency. The L-canavanine induced apoptotic cells can be phagocytosed and a source of autoantigens processed by endosomal proteases. Endogenous canavanyl proteins are ubiquitinated and processed via proteasome. Incorporation of L-canavanine into proteasome or endosome can also cause disruption of antigen processing. Alfalfa/L-canavanine-induced lupus will be an interesting model of autoimmunity induced by the modification of self-proteins at the translational level.
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Affiliation(s)
- Jun Akaogi
- Division of Rheumatology and Clinical Immunology, Department of Medicine, University of Florida, Gainesville, FL 32610-0221, USA
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Jun DY, Rue SW, Han KH, Taub D, Lee YS, Bae YS, Kim YH. Mechanism underlying cytotoxicity of thialysine, lysine analog, toward human acute leukemia Jurkat T cells. Biochem Pharmacol 2003; 66:2291-300. [PMID: 14637187 DOI: 10.1016/j.bcp.2003.08.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
We first report the mechanism for the inhibitory effect of the lysine analog, thialysine on human acute leukemia Jurkat T cells. When Jurkat T cells were treated with thialysine (0.32-2.5 mM), apoptotic cell death along with several biochemical events such as mitochondrial cytochrome c release, caspase-9 activation, caspase-3 activation, degradation of poly (ADP-ribose) polymerase, and DNA fragmentation was induced in a dose- and time-dependent manner. However, these thialysine-induced apoptotic events were significantly abrogated by an ectopic expression of Bcl-xL, which is known to block mitochondrial cytochrome c release. Decylubiquinone, a mitochondrial permeability transition pore inhibitor, also suppressed thialysine-induced apoptotic events. Comparison of the thialysine-induced alterations in the cell cycle distribution between Jurkat T cells transfected with Bcl-xL gene (J/Bcl-xL) and Jurkat T cells transfected with vector (J/Neo) revealed that the apoptotic cells were mainly derived from the cells accumulated in S and G2/M phases following thialysine treatment. The interruption of cell cycle progression in the presence of thialysine was accompanied by a significant decline in the protein level of cdk4, cdk6, cdc2, cyclin A, cyclin B1, and cyclin E. These results demonstrate that the cytotoxic activity of thialysine toward Jurkat T cells is attributable to not only apoptotic cell death mediated by a mitochondria-dependent death signaling pathway, but also interruption of cell cycle progression by a massive down-regulation in the level of cdks and cyclins.
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Affiliation(s)
- Do Youn Jun
- Laboratory of Immunobiology, Department of Microbiology, College of Natural Sciences, Kyungpook National University, 702-701 Taegu, South Korea
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Jang MH, Jun DY, Rue SW, Han KH, Park W, Kim YH. Arginine antimetabolite L-canavanine induces apoptotic cell death in human Jurkat T cells via caspase-3 activation regulated by Bcl-2 or Bcl-xL. Biochem Biophys Res Commun 2002; 295:283-8. [PMID: 12150944 DOI: 10.1016/s0006-291x(02)00650-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
L-Canavanine, a natural L-arginine analog, is known to possess cytotoxicity to tumor cells in culture and experimental tumors in vivo. In this study, we first show that apoptotic cell death is associated with antitumor activity of L-canavanine against human acute leukemia Jurkat T cells. When Jurkat T cells were treated with 1.25-5.0mM L-canavanine for 36 h, apoptotic cell death accompanying several biochemical events such as caspase-3 activation, degradation of poly(ADP-ribose) polymerase (PARP), and apoptotic DNA fragmentation was induced in a dose-dependent manner; however, cytochrome c release from mitochondria was not detected. Under these conditions, the expression of Bcl-2 and its functional homolog Bcl-xL was markedly upregulated. The L-canavanine-induced caspase-3 activation, degradation of PARP, and apoptotic DNA fragmentation were suppressed by ectopic expression of Bcl-2 or Bcl-xL, both of which are known to play roles as anti-apoptotic regulators. These results demonstrate that the cytotoxic effect of L-canavanine on Jurkat T cells is attributable to the induced apoptosis and that L-canavanine-induced apoptosis is mediated by a cytochrome c-independent caspase-3 activation pathway that can be interrupted by Bcl-2 or Bcl-xL.
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Affiliation(s)
- Myung Ho Jang
- Laboratory of Immunobiology, Department of Microbiology, College of Natural Sciences, Kyungpook National University, Taegu 702-701, Republic of Korea
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Bence AK, Worthen DR, Adams VR, Crooks PA. The antiproliferative and immunotoxic effects of L-canavanine and L-canaline. Anticancer Drugs 2002; 13:313-20. [PMID: 11984075 DOI: 10.1097/00001813-200203000-00013] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
L-Canavanine and its arginase-catalyzed metabolite, L-canaline, are two novel anticancer agents in development. Since the immunotoxic evaluation of agents in development is a critical component of the drug development process, the antiproliferative effects of L-canavanine and L-canaline were evaluated in vitro. Both L-canavanine and L-canaline were cytotoxic to peripheral blood mononucleocytes (PBMCs) in culture. Additionally, the mononucleocytes were concurrently exposed to either L-canavanine or L-canaline and each one of a series of compounds that may act as metabolic inhibitors of the action of L-canavanine and L-canaline (L-arginine, L-ornithine, D-arginine, L-lysine, L-homoarginine, putrescine, L-omega-nitro arginine methyl ester and L-citrulline). The capacity of these compounds to overcome the cytotoxic effects of L-canavanine or L-canaline was assessed in order to provide insight into the biochemical mechanisms that may underlie the toxicity of these two novel anticancer agents. The results of these studies suggest that the mechanism of L-canavanine toxicity is mediated through L-arginine-utilizing mechanisms and that the L-canavanine metabolite, L-canaline, is toxic to human PBMCs by disrupting polyamine biosynthesis. The elucidation of the biochemical mechanisms associated with the effects of L-canavanine and L-canaline on lymphoproliferation may be useful for maximizing the therapeutic effectiveness and minimizing the toxicity of these novel anticancer agents.
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Affiliation(s)
- Aimee K Bence
- Division of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, Lexington, KY 40536, USA
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Peng Z, Staub JM, Serino G, Kwok SF, Kurepa J, Bruce BD, Vierstra RD, Wei N, Deng XW. The cellular level of PR500, a protein complex related to the 19S regulatory particle of the proteasome, is regulated in response to stresses in plants. Mol Biol Cell 2001; 12:383-92. [PMID: 11179422 PMCID: PMC30950 DOI: 10.1091/mbc.12.2.383] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2000] [Revised: 11/29/2000] [Accepted: 12/19/2000] [Indexed: 11/11/2022] Open
Abstract
In Arabidopsis seedlings and cauliflower florets, Rpn6 (a proteasome non-ATPase regulatory subunit) was found in two distinct protein complexes of approximately 800 and 500 kDa, respectively. The large complex likely represents the proteasome 19S regulator particle (RP) because it displays the expected subunit composition and all characteristics. The small complex, designated PR500, shares at least three subunits with the "lid" subcomplex of 19S RP and is loosely associated with an hsp70 protein. In Arabidopsis COP9 signalosome mutants, PR500 was specifically absent or reduced to an extent that correlates with the severity of the mutations. Furthermore, PR500 was also diminished in response to potential protein-misfolding stresses caused by the heat shock and canavanine treatment. Immunofluorescence studies suggest that PR500 has a distinct localization pattern and is enriched in specific nuclear foci. We propose that PR500 may be evolved in higher plants to cope with the frequently encountered environmental stresses.
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Affiliation(s)
- Z Peng
- Department of Molecular, Cellular, and Developmental Biology, Yale University, New Haven, Connecticut 06520-8104, USA
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Rosenthal GA, Harper L. L-homoarginine studies provide insight into the antimetabolic properties of L-canavanine. INSECT BIOCHEMISTRY AND MOLECULAR BIOLOGY 1996; 26:389-394. [PMID: 8814786 DOI: 10.1016/0965-1748(95)00106-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
A method for the chemical synthesis of L-homoarginine, based on the guanidination of L-lysine with O-methylisourea, has been developed; this procedure provides radiochemically pure L-[guanidino-14C]homoarginine in high yield. Radiolabeled homoarginine is incorporated readily into the newly synthesized hemolymphic proteins of larvae of the tobacco hornworm, Manduca sexta without adversely affecting larval growth and development. This finding stands in sharp contrast to the effect of L-canavanine, another L-arginine analog, which is markedly deleterious to these larvae. Homoarginine is incorporated into M. sexta lysozyme, and the antibacterial proteins of the fly, Phormia terranovae with impunity. In contrast, the comparable canavanine-containing enzymes are inhibited severely. Experimental evidence is presented that the innocuous nature of homoarginine results from the elevated pKa value of its guanidino group which arguably exceeds even that of arginine. As a result, homoarginine does not disrupt essential residue interactions. In contrast canavanine, which is much less basic than arginine, does adversely affect R group interactions forming the requisite three-dimensional conformation of the protein.
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Affiliation(s)
- G A Rosenthal
- Laboratory of Biochemical Ecology, T. H. Morgan School of Biological Sciences, University of Kentucky, Lexington 40506-0054, USA
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Hinks C, Hupka D, Olfert O. Nutrition and the protein economy in grasshoppers and locusts. ACTA ACUST UNITED AC 1993. [DOI: 10.1016/0300-9629(93)90020-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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