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Soudais C, Schaus R, Bachelet C, Minet N, Mouasni S, Garcin C, Souza CL, David P, Cousu C, Asnagli H, Parker A, Palmquist-Gomes P, Sepulveda FE, Storck S, Meilhac SM, Fischer A, Martin E, Latour S. Inactivation of cytidine triphosphate synthase 1 prevents fatal auto-immunity in mice. Nat Commun 2024; 15:1982. [PMID: 38438357 PMCID: PMC10912214 DOI: 10.1038/s41467-024-45805-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 01/25/2024] [Indexed: 03/06/2024] Open
Abstract
De novo synthesis of the pyrimidine, cytidine triphosphate (CTP), is crucial for DNA/RNA metabolism and depends on the CTP synthetases, CTPS1 and -2. Partial CTPS1 deficiency in humans has previously been shown to lead to immunodeficiency, with impaired expansion of T and B cells. Here, we examine the effects of conditional and inducible inactivation of Ctps1 and/or Ctps2 on mouse embryonic development and immunity. We report that deletion of Ctps1, but not Ctps2, is embryonic-lethal. Tissue and cells with high proliferation and renewal rates, such as intestinal epithelium, erythroid and thymic lineages, activated B and T lymphocytes, and memory T cells strongly rely on CTPS1 for their maintenance and growth. However, both CTPS1 and CTPS2 are required for T cell proliferation following TCR stimulation. Deletion of Ctps1 in T cells or treatment with a CTPS1 inhibitor rescued Foxp3-deficient mice from fatal systemic autoimmunity and reduced the severity of experimental autoimmune encephalomyelitis. These findings support that CTPS1 may represent a target for immune suppression.
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Affiliation(s)
- Claire Soudais
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France.
- Université de Paris Cité, Paris, France.
| | - Romane Schaus
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
| | - Camille Bachelet
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
- Université de Paris Cité, Paris, France
| | - Norbert Minet
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
- Université de Paris Cité, Paris, France
| | - Sara Mouasni
- Laboratory of Molecular Basis of Altered Immune Homeostasis Inserm UMR 1163, Institut Imagine, Paris, France
| | - Cécile Garcin
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
- Université de Paris Cité, Paris, France
| | - Caique Lopes Souza
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
- Université de Paris Cité, Paris, France
| | - Pierre David
- Transgenesis Platform, Laboratoire d'Expérimentation Animale et Transgenèse (LEAT), Institut Imagine-Structure Fédérative de Recherche Necker INSERM US24/CNRS, UMS3633, Paris, France
| | - Clara Cousu
- Université Paris Cité, CNRS UMR 8253, INSERM U1151, Institut Necker Enfants Malades, F-75015, Paris, France
| | - Hélène Asnagli
- Step-Pharma, Technoparc du Pays-de-Gex, Saint-Genis-Pouilly, France
| | - Andrew Parker
- Step-Pharma, Technoparc du Pays-de-Gex, Saint-Genis-Pouilly, France
| | - Paul Palmquist-Gomes
- Université de Paris Cité, Paris, France
- Imagine - Institut Pasteur, Unit of Heart Morphogenesis, INSERM UMR1163, F-75015, Paris, France
| | - Fernando E Sepulveda
- Laboratory of Molecular Basis of Altered Immune Homeostasis Inserm UMR 1163, Institut Imagine, Paris, France
| | - Sébastien Storck
- Université Paris Cité, CNRS UMR 8253, INSERM U1151, Institut Necker Enfants Malades, F-75015, Paris, France
| | - Sigolène M Meilhac
- Université de Paris Cité, Paris, France
- Imagine - Institut Pasteur, Unit of Heart Morphogenesis, INSERM UMR1163, F-75015, Paris, France
| | - Alain Fischer
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
- Collège de France, Paris, France
| | - Emmanuel Martin
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France
| | - Sylvain Latour
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Institut Imagine, Paris, France.
- Université de Paris Cité, Paris, France.
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Minet N, Boschat AC, Lane R, Laughton D, Beer P, Asnagli H, Soudais C, Bourne T, Fischer A, Martin E, Latour S. Differential roles of CTP synthetases CTPS1 and CTPS2 in cell proliferation. Life Sci Alliance 2023; 6:e202302066. [PMID: 37348953 PMCID: PMC10288033 DOI: 10.26508/lsa.202302066] [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: 03/29/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/24/2023] Open
Abstract
The CTP nucleotide is a key precursor of nucleic acids metabolism essential for DNA replication. De novo CTP production relies on CTP synthetases 1 and 2 (CTPS1 and CTPS2) that catalyze the conversion of UTP into CTP. CTP synthetase activity is high in proliferating cells including cancer cells; however, the respective roles of CTPS1 and CTPS2 in cell proliferation are not known. By inactivation of CTPS1 and/or CTPS2 and complementation experiments, we showed that both CTPS1 and CTPS2 are differentially required for cell proliferation. CTPS1 was more efficient in promoting proliferation than CTPS2, in association with a higher intrinsic enzymatic activity that was more resistant to inhibition by 3-deaza-uridine, an UTP analog. The contribution of CTPS2 to cell proliferation was modest when CTPS1 was expressed but essential in absence of CTPS1. Public databases analysis of more than 1,000 inactivated cancer cell lines for CTPS1 or CTPS2 confirmed that cell growth is highly dependent of CTPS1 but less or not of CTPS2. Therefore, our results demonstrate that CTPS1 is the main contributor to cell proliferation.
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Affiliation(s)
- Norbert Minet
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, Inserm UMR 1163, Imagine Institute, Paris, France
- Université de Paris, Paris, France
| | - Anne-Claire Boschat
- Université de Paris, Paris, France
- Plateforme Spectrométrie de masse, Institut Imagine, Paris, France
- Laboratoire de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants-Malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | | | | | | | | | - Claire Soudais
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, Inserm UMR 1163, Imagine Institute, Paris, France
- Université de Paris, Paris, France
| | - Tim Bourne
- Step-Pharma, Saint-Genis-Pouilly, France
| | - Alain Fischer
- Collège de France, Paris, France
- Imagine Institute, Paris, France
| | - Emmanuel Martin
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, Inserm UMR 1163, Imagine Institute, Paris, France
- Université de Paris, Paris, France
| | - Sylvain Latour
- Laboratory of Lymphocyte Activation and Susceptibility to EBV Infection, Inserm UMR 1163, Imagine Institute, Paris, France
- Université de Paris, Paris, France
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Hu X, Han Y, Liu J, Wang H, Tian Z, Zhang X, Zhang Y, Wang X. CTP synthase 2 predicts inferior survival and mediates DNA damage response via interacting with BRCA1 in chronic lymphocytic leukemia. Exp Hematol Oncol 2023; 12:6. [PMID: 36635772 PMCID: PMC9835321 DOI: 10.1186/s40164-022-00364-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 12/29/2022] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Cytidine triphosphate synthase 2 (CTPS2) is an essential metabolic enzyme that catalyzes the biosynthesis of CTP. CTP synthases contribute to lymphocytes proliferation and tumorigenesis, but the role of CTPS2 in chronic lymphocytic leukemia (CLL) remains undefined. METHODS In silico analysis was performed to quantified the expression and clinical analysis of CTPS2 and BRCA1. The expression was then validated on the internal sets. Loss-and gain-of-function assays were conducted to investigate the physiological phenotypes in CLL. RNA-seq was employed to probe the molecular mechanism of CTPS2. RESULTS Herein, significant elevated expression of CTPS2 was observed in CLL patients compared to normal CD19 + B cells, which was verified in three independent cohorts. Furthermore, overexpression of CTPS2 was closely associated with undesired prognostic indicators, including unmutated IGHV status and chromosome 11q23 deletion. Additionally, elevated CTPS2 expression predicted adverse overall survival and treatment-free survival with independent prognostic significance. Downregulation of CTPS2 in CLL cells exhibited attenuated cell proliferation, arrested G2/M cell cycle and increased apoptosis. The addition of CTP or glutamine could reverse the above effects. Since RNA-seq showed the enrichment in DNA damage and response signaling, we subsequently found that silence of CTPS2 remarkably elevated DNA damage and decreased DNA repair. It was demonstrated that CTPS2 mediated DNA damage response via interacting with Breast Cancer 1 (BRCA1) protein in CLL through CoIP assays and rescued experiments. CONCLUSIONS Collectively, our study generated the novel findings that CTPS2 promoted CLL progression via DNA damage response and repair pathway. Targeting nucleotide metabolism potentially became an attractive strategy for treatment against CLL.
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Affiliation(s)
- Xinting Hu
- grid.27255.370000 0004 1761 1174Department of Hematology, Shandong Provincial Hospital, Shandong University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Yang Han
- grid.460018.b0000 0004 1769 9639Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Jiarui Liu
- grid.460018.b0000 0004 1769 9639Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Hua Wang
- grid.460018.b0000 0004 1769 9639Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Zheng Tian
- grid.27255.370000 0004 1761 1174Department of Hematology, Shandong Provincial Hospital, Shandong University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Xin Zhang
- grid.27255.370000 0004 1761 1174Department of Hematology, Shandong Provincial Hospital, Shandong University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Ya Zhang
- grid.460018.b0000 0004 1769 9639Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
| | - Xin Wang
- grid.27255.370000 0004 1761 1174Department of Hematology, Shandong Provincial Hospital, Shandong University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,grid.460018.b0000 0004 1769 9639Department of Hematology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, No.324, Jingwu Road, Jinan, 250021 Shandong China ,Shandong Provincial Engineering Research Center of Lymphoma, Jinan, 250021 Shandong China ,Branch of National Clinical Research Center for Hematologic Diseases, Jinan, 250021 Shandong China ,grid.429222.d0000 0004 1798 0228National Clinical Research Center for Hematologic Diseases, The First Affiliated Hospital of Soochow University, Suzhou, 251006 China
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Paria P, Tassanakajon A. Identification of Potential Druggable Targets and Structure-Based Virtual Screening for Drug-like Molecules against the Shrimp Pathogen Enterocytozoon hepatopenaei. Int J Mol Sci 2023; 24:ijms24021412. [PMID: 36674953 PMCID: PMC9867128 DOI: 10.3390/ijms24021412] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/26/2022] [Accepted: 01/05/2023] [Indexed: 01/13/2023] Open
Abstract
Enterocytozoon hepatopenaei (EHP) causes slow growth syndrome in shrimp, resulting in huge economic losses for the global shrimp industry. Despite worldwide reports, there are no effective therapeutics for controlling EHP infections. In this study, five potential druggable targets of EHP, namely, aquaporin (AQP), cytidine triphosphate (CTP) synthase, thymidine kinase (TK), methionine aminopeptidase2 (MetAP2), and dihydrofolate reductase (DHFR), were identified via functional classification of the whole EHP proteome. The three-dimensional structures of the proteins were constructed using the artificial-intelligence-based program AlphaFold 2. Following the prediction of druggable sites, the ZINC15 and ChEMBL databases were screened against targets using docking-based virtual screening. Molecules with affinity scores ≥ 7.5 and numbers of interactions ≥ 9 were initially selected and subsequently enriched based on their ADMET properties and electrostatic complementarities. Five compounds were finally selected against each target based on their complex stabilities and binding energies. The compounds CHEMBL3703838, CHEMBL2132563, and CHEMBL133039 were selected against AQP; CHEMBL1091856, CHEMBL1162979, and CHEMBL525202 against CTP synthase; CHEMBL4078273, CHEMBL1683320, and CHEMBL3674540 against TK; CHEMBL340488, CHEMBL1966988, and ZINC000828645375 against DHFR; and CHEMBL3913373, ZINC000016682972, and CHEMBL3142997 against MetAP2.The compounds exhibited high stabilities and low binding free energies, indicating their abilities to suppress EHP infections; however, further validation is necessary for determining their efficacy.
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Wu F, Mao Y, Ma T, Wang X, Wei H, Wang T, Wang J, Zhang Y. CTPS1 inhibition suppresses proliferation and migration in colorectal cancer cells. Cell Cycle 2022; 21:2563-2574. [PMID: 35912542 PMCID: PMC9704378 DOI: 10.1080/15384101.2022.2105084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
Colorectal cancer (CRC) is now the third most prevalent tumor and one of the deadliest cancers worldwide, with an increasing prevalence every year. Therefore, we urgently need to understand the mechanisms regulating the progression of colorectal cancer and find potential diagnostic biomarkers. In this study, we performed an analysis using the TCGA and GEO databases to find a molecular biomarker for the diagnosis of CRC, namely CTPS1. The results of this analysis revealed that CTPS1 could promote tumor proliferation and metastasis. Furthermore, bioinformatics analysis revealed that CTPS1 promoted CRC progression through cell cycle and p53 pathways. Further investigation demonstrated that CTPS1 might be involved in the regulation of CCNB1, RRM2, GTSE1, CDK2 and CHEK2 genes. Moreover, PCR confirmed that CTPS1 regulated GTSE1 and CDK2 molecules. Then, western blot was used to verify that CTPS1 promoted the expression of GTSE1 and CDK2 by inhibiting the expression of p53. In summary, we identified an important diagnostic biomarker for CRC, namely CTPS1, and its importance was validated at the cellular level. These results suggest that CTPS1 could serve as a candidate biomarker for CRC and CTPS1 inhibitors may be a potential treatment for CRC.
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Affiliation(s)
- Fahong Wu
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China
| | - Yudong Mao
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China
| | - Tao Ma
- Department of Hematology, the Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Xiaoli Wang
- Department of Obstetrics and Gynecology, Xiamen Third Hospital, Xiamen, China
| | - Hangzhi Wei
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China
| | - Tianwei Wang
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China
| | - Jia Wang
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China
| | - Youcheng Zhang
- Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, China,CONTACT Youcheng Zhang Department of General Surgery, Hepatic-biliary-pancreatic Institute, Lanzhou University Second Hospital, Lanzhou, 730030, China
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Alqahtani SS, Koltai T, Ibrahim ME, Bashir AHH, Alhoufie STS, Ahmed SBM, Molfetta DD, Carvalho TMA, Cardone RA, Reshkin SJ, Hifny A, Ahmed ME, Alfarouk KO. Role of pH in Regulating Cancer Pyrimidine Synthesis. J Xenobiot 2022; 12:158-180. [PMID: 35893264 PMCID: PMC9326563 DOI: 10.3390/jox12030014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/17/2022] [Accepted: 06/28/2022] [Indexed: 11/18/2022] Open
Abstract
Replication is a fundamental aspect of cancer, and replication is about reproducing all the elements and structures that form a cell. Among them are DNA, RNA, enzymes, and coenzymes. All the DNA is doubled during each S (synthesis) cell cycle phase. This means that six billion nucleic acids must be synthesized in each cycle. Tumor growth, proliferation, and mutations all depend on this synthesis. Cancer cells require a constant supply of nucleotides and other macromolecules. For this reason, they must stimulate de novo nucleotide synthesis to support nucleic acid provision. When deregulated, de novo nucleic acid synthesis is controlled by oncogenes and tumor suppressor genes that enable increased synthesis and cell proliferation. Furthermore, cell duplication must be achieved swiftly (in a few hours) and in the midst of a nutrient-depleted and hypoxic environment. This also means that the enzymes participating in nucleic acid synthesis must work efficiently. pH is a critical factor in enzymatic efficiency and speed. This review will show that the enzymatic machinery working in nucleic acid synthesis requires a pH on the alkaline side in most cases. This coincides with many other pro-tumoral factors, such as the glycolytic phenotype, benefiting from an increased intracellular pH. An increased intracellular pH is a perfect milieu for high de novo nucleic acid production through optimal enzymatic performance.
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Affiliation(s)
- Saad Saeed Alqahtani
- Department of Pharmacy Practice, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia;
- Pharmacy Practice Research Unit, College of Pharmacy, Jazan University, Jazan 45142, Saudi Arabia
| | | | - Muntaser E. Ibrahim
- Department of Molecular Biology, Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan; (M.E.I.); (A.H.H.B.)
| | - Adil H. H. Bashir
- Department of Molecular Biology, Institute of Endemic Diseases, University of Khartoum, Khartoum 11111, Sudan; (M.E.I.); (A.H.H.B.)
| | - Sari T. S. Alhoufie
- Medical Laboratories Technology Department, College of Applied Medical Sciences, Taibah University, Medina 42353, Saudi Arabia;
| | - Samrein B. M. Ahmed
- Department of Biosciences and Chemistry, College of Health, Wellbeing and Life Sciences, Sheffield Hallam University, Sheffield S1 1WB, UK;
| | - Daria Di Molfetta
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (D.D.M.); (T.M.A.C.); (R.A.C.); (S.J.R.)
| | - Tiago M. A. Carvalho
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (D.D.M.); (T.M.A.C.); (R.A.C.); (S.J.R.)
| | - Rosa Angela Cardone
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (D.D.M.); (T.M.A.C.); (R.A.C.); (S.J.R.)
| | - Stephan Joel Reshkin
- Department of Biosciences, Biotechnologies, and Biopharmaceutics, University of Bari, 70126 Bari, Italy; (D.D.M.); (T.M.A.C.); (R.A.C.); (S.J.R.)
| | | | - Mohamed E. Ahmed
- Research Center, Zamzam University College, Khartoum 11123, Sudan;
| | - Khalid Omer Alfarouk
- Research Center, Zamzam University College, Khartoum 11123, Sudan;
- Alfarouk Biomedical Research LLC, Temple Terrace, FL 33617, USA
- Hala Alfarouk Cancer Center, Khartoum 11123, Sudan
- Correspondence:
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GTP-Dependent Regulation of CTP Synthase: Evolving Insights into Allosteric Activation and NH3 Translocation. Biomolecules 2022; 12:biom12050647. [PMID: 35625575 PMCID: PMC9138612 DOI: 10.3390/biom12050647] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 04/21/2022] [Accepted: 04/21/2022] [Indexed: 12/24/2022] Open
Abstract
Cytidine-5′-triphosphate (CTP) synthase (CTPS) is the class I glutamine-dependent amidotransferase (GAT) that catalyzes the last step in the de novo biosynthesis of CTP. Glutamine hydrolysis is catalyzed in the GAT domain and the liberated ammonia is transferred via an intramolecular tunnel to the synthase domain where the ATP-dependent amination of UTP occurs to form CTP. CTPS is unique among the glutamine-dependent amidotransferases, requiring an allosteric effector (GTP) to activate the GAT domain for efficient glutamine hydrolysis. Recently, the first cryo-electron microscopy structure of Drosophila CTPS was solved with bound ATP, UTP, and, notably, GTP, as well as the covalent adduct with 6-diazo-5-oxo-l-norleucine. This structural information, along with the numerous site-directed mutagenesis, kinetics, and structural studies conducted over the past 50 years, provide more detailed insights into the elaborate conformational changes that accompany GTP binding at the GAT domain and their contribution to catalysis. Interactions between GTP and the L2 loop, the L4 loop from an adjacent protomer, the L11 lid, and the L13 loop (or unique flexible “wing” region), induce conformational changes that promote the hydrolysis of glutamine at the GAT domain; however, direct experimental evidence on the specific mechanism by which these conformational changes facilitate catalysis at the GAT domain is still lacking. Significantly, the conformational changes induced by GTP binding also affect the assembly and maintenance of the NH3 tunnel. Hence, in addition to promoting glutamine hydrolysis, the allosteric effector plays an important role in coordinating the reactions catalyzed by the GAT and synthase domains of CTPS.
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Sun Z, Zhang Z, Wang QQ, Liu JL. Combined Inactivation of CTPS1 and ATR Is Synthetically Lethal to MYC-Overexpressing Cancer Cells. Cancer Res 2022; 82:1013-1024. [PMID: 35022212 PMCID: PMC9359733 DOI: 10.1158/0008-5472.can-21-1707] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Revised: 09/30/2021] [Accepted: 12/28/2021] [Indexed: 01/07/2023]
Abstract
The "undruggable" oncogene MYC supports cancer cell proliferation and survival through parallel induction of multiple anabolic processes. Here we find that inhibiting CTP synthase (CTPS) selectively decreases cell viability and induces DNA replication stress in MYC-overexpressing cells. MYC-driven rRNA synthesis caused the selective DNA replication stress upon CTPS inhibition. Combined inhibition of CTPS and ataxia telangiectasia and Rad3-related protein (ATR) is synthetically lethal in MYC-overexpressing cells, promoting cell death in vitro and decreasing tumor growth in vivo. Unexpectedly, interfering with CTPS1 but not CTPS2 is required to induce replication stress in MYC-deregulated cancer cells and consequent cell death in the presence of an ATR inhibitor. These results highlight a specific and key role of CTPS1 in MYC-driven cancer, suggesting that selectively inhibiting CTPS1 in combination with ATR could be a promising strategy to combat disease progression. SIGNIFICANCE Inhibition of CTPS in MYC-overexpressing cells blocks pyrimidine synthesis while maintaining ribosome synthesis activity to create an anabolic imbalance that induces replication stress, providing a new approach to selectively target MYC-driven cancer. See related commentary by Chabanon and Postel-Vinay, p. 969.
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Affiliation(s)
- Zhe Sun
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ziheng Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Qiao-Qi Wang
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China
| | - Ji-Long Liu
- School of Life Science and Technology, ShanghaiTech University, Shanghai, China.,Corresponding Author: Ji-Long Liu, School of Life Science and Technology, ShanghaiTech University, 393 Middle Huaxia Road, Pudong, Shanghai, 201210, China. Phone: 8618-2176-28315; E-mail:
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Abstract
Epstein-Barr virus (EBV) is associated with 200,000 cancers annually, including B-cell lymphomas in immunosuppressed hosts. Hypomorphic mutations of the de novo pyrimidine synthesis pathway enzyme cytidine 5′ triphosphate synthase 1 (CTPS1) suppress cell-mediated immunity, resulting in fulminant EBV infection and EBV+ central nervous system (CNS) lymphomas. Since CTP is a critical precursor for DNA, RNA, and phospholipid synthesis, this observation raises the question of whether the isozyme CTPS2 or cytidine salvage pathways help meet CTP demand in EBV-infected B cells. Here, we found that EBV upregulated CTPS1 and CTPS2 with distinct kinetics in newly infected B cells. While CRISPR CTPS1 knockout caused DNA damage and proliferation defects in lymphoblastoid cell lines (LCLs), which express the EBV latency III program observed in CNS lymphomas, double CTPS1/2 knockout caused stronger phenotypes. EBNA2, MYC, and noncanonical NF-κB positively regulated CTPS1 expression. CTPS1 depletion impaired EBV lytic DNA synthesis, suggesting that latent EBV may drive pathogenesis with CTPS1 deficiency. Cytidine rescued CTPS1/2 deficiency phenotypes in EBV-transformed LCLs and Burkitt B cells, highlighting CTPS1/2 as a potential therapeutic target for EBV-driven lymphoproliferative disorders. Collectively, our results suggest that CTPS1 and CTPS2 have partially redundant roles in EBV-transformed B cells and provide insights into EBV pathogenesis with CTPS1 deficiency.
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Miljanovic N, Hauck SM, van Dijk RM, Di Liberto V, Rezaei A, Potschka H. Proteomic signature of the Dravet syndrome in the genetic Scn1a-A1783V mouse model. Neurobiol Dis 2021; 157:105423. [PMID: 34144125 DOI: 10.1016/j.nbd.2021.105423] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 05/14/2021] [Accepted: 06/08/2021] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Dravet syndrome is a rare, severe pediatric epileptic encephalopathy associated with intellectual and motor disabilities. Proteomic profiling in a mouse model of Dravet syndrome can provide information about the molecular consequences of the genetic deficiency and about pathophysiological mechanisms developing during the disease course. METHODS A knock-in mouse model of Dravet syndrome with Scn1a haploinsufficiency was used for whole proteome, seizure, and behavioral analysis. Hippocampal tissue was dissected from two- (prior to epilepsy manifestation) and four- (following epilepsy manifestation) week-old male mice and analyzed using LC-MS/MS with label-free quantification. Proteomic data sets were subjected to bioinformatic analysis including pathway enrichment analysis. The differential expression of selected proteins was confirmed by immunohistochemical staining. RESULTS The findings confirmed an increased susceptibility to hyperthermia-associated seizures, the development of spontaneous seizures, and behavioral alterations in the novel Scn1a-A1873V mouse model of Dravet syndrome. As expected, proteomic analysis demonstrated more pronounced alterations following epilepsy manifestation. In particular, proteins involved in neurotransmitter dynamics, receptor and ion channel function, synaptic plasticity, astrogliosis, neoangiogenesis, and nitric oxide signaling showed a pronounced regulation in Dravet mice. Pathway enrichment analysis identified several significantly regulated pathways at the later time point, with pathways linked to synaptic transmission and glutamatergic signaling dominating the list. CONCLUSION In conclusion, the whole proteome analysis in a mouse model of Dravet syndrome demonstrated complex molecular alterations in the hippocampus. Some of these alterations may have an impact on excitability or may serve a compensatory function, which, however, needs to be further confirmed by future investigations. The proteomic data indicate that, due to the molecular consequences of the genetic deficiency, the pathophysiological mechanisms may become more complex during the course of the disease. As a result, the management of Dravet syndrome may need to consider further molecular and cellular alterations. Ensuing functional follow-up studies, this data set may provide valuable guidance for the future development of novel therapeutic approaches.
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Affiliation(s)
- Nina Miljanovic
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany; Graduate School of Systemic Neurosciences (GSN), Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Stefanie M Hauck
- Research Unit Protein Science, Helmholtz Zentrum München, German Research Center for Environmental Health (GmbH), Germany
| | - R Maarten van Dijk
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Valentina Di Liberto
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Ali Rezaei
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany; Graduate School of Systemic Neurosciences (GSN), Ludwig-Maximilians-University (LMU), Munich, Germany
| | - Heidrun Potschka
- Institute of Pharmacology, Toxicology & Pharmacy, Ludwig-Maximilians-University (LMU), Munich, Germany.
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11
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Jia F, Chi C, Han M. Regulation of Nucleotide Metabolism and Germline Proliferation in Response to Nucleotide Imbalance and Genotoxic Stresses by EndoU Nuclease. Cell Rep 2021; 30:1848-1861.e5. [PMID: 32049015 PMCID: PMC7050212 DOI: 10.1016/j.celrep.2020.01.050] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 12/06/2019] [Accepted: 01/15/2020] [Indexed: 12/23/2022] Open
Abstract
Nucleotide deprivation and imbalance present detrimental conditions for animals and are thus expected to trigger cellular responses that direct protective changes in metabolic, developmental, and behavioral programs, albeit such mechanisms are vastly underexplored. Following our previous finding that Caenorhabditis elegans shut down germ cell proliferation in response to pyrimidine deprivation, we find in this study that endonuclease ENDU-2 regulates nucleotide metabolism and germ cell proliferation in response to nucleotide imbalance and other genotoxic stress, and that it affects mitotic chromosomal segregation in the intestine and lifespan. ENDU-2 expression is induced by nucleotide imbalance and genotoxic stress, and ENDU-2 exerts its function in the intestine, mostly by inhibiting the phosphorylation of CTPS-1 through repressing the PKA pathway and histone deacetylase HDA-1. Human EndoU also affects the response to genotoxic drugs. Our work reveals an unknown role of ENDU-2 in regulating nucleotide metabolism and animals' response to genotoxic stress, which may link EndoU function to cancer treatment.
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Affiliation(s)
- Fan Jia
- Department of Molecular, Cellular, and Developmental Biology (MCDB), University of Colorado at Boulder, Boulder, CO 80309-0347, USA.
| | - Congwu Chi
- Department of Molecular, Cellular, and Developmental Biology (MCDB), University of Colorado at Boulder, Boulder, CO 80309-0347, USA
| | - Min Han
- Department of Molecular, Cellular, and Developmental Biology (MCDB), University of Colorado at Boulder, Boulder, CO 80309-0347, USA
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12
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Rao Y, Wang TY, Qin C, Espinosa B, Liu Q, Ekanayake A, Zhao J, Savas AC, Zhang S, Zarinfar M, Liu Y, Zhu W, Graham N, Jiang T, Zhang C, Feng P. Targeting CTP Synthetase 1 to Restore Interferon Induction and Impede Nucleotide Synthesis in SARS-CoV-2 Infection. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2021:2021.02.05.429959. [PMID: 33564769 PMCID: PMC7872357 DOI: 10.1101/2021.02.05.429959] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The newly emerged SARS-CoV-2 caused a global pandemic with astonishing mortality and morbidity. The mechanisms underpinning its highly infectious nature remain poorly understood. We report here that SARS-CoV-2 exploits cellular CTP synthetase 1 (CTPS1) to promote CTP synthesis and suppress interferon (IFN) induction. Screening a SARS-CoV-2 expression library identified ORF7b and ORF8 that suppressed IFN induction via inducing the deamidation of interferon regulatory factor 3 (IRF3). Deamidated IRF3 fails to bind the promoters of classic IRF3-responsible genes, thus muting IFN induction. Conversely, a shRNA-mediated screen focused on cellular glutamine amidotransferases corroborated that CTPS1 deamidates IRF3 to inhibit IFN induction. Functionally, ORF7b and ORF8 activate CTPS1 to promote de novo CTP synthesis while shutting down IFN induction. De novo synthesis of small-molecule inhibitors of CTPS1 enabled CTP depletion and IFN induction in SARS-CoV-2 infection, thus impeding SARS-CoV-2 replication. Our work uncovers a strategy that a viral pathogen couples immune evasion to metabolic activation to fuel viral replication. Inhibition of the cellular CTPS1 offers an attractive means for developing antiviral therapy that would be resistant to SARS-CoV-2 mutation.
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Affiliation(s)
- Youliang Rao
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Ting-Yu Wang
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Chao Qin
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Bianca Espinosa
- Department of Chemistry, Dornsife College of Arts, Letters and Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Qizhi Liu
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Arunika Ekanayake
- Department of Chemistry, Dornsife College of Arts, Letters and Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Jun Zhao
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
- Florida Research and Innovation Center, Cleveland Clinic, FL 34987, USA
| | - Ali Can Savas
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Shu Zhang
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Mehrnaz Zarinfar
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Yongzhen Liu
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
| | - Wenjie Zhu
- Center for Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005; Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123; Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), 510005 Guangzhou, China
| | - Nicholas Graham
- Mork Family Department of Chemical Engineering and Materials Science, Norris Comprehensive Cancer Center, Los Angeles, CA 90089, USA
| | - Taijiao Jiang
- Center for Systems Medicine, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100005; Suzhou Institute of Systems Medicine, Suzhou, Jiangsu 215123; Bioland Laboratory (Guangzhou Regenerative Medicine and Health Guangdong Laboratory), 510005 Guangzhou, China
| | - Chao Zhang
- Department of Chemistry, Dornsife College of Arts, Letters and Sciences, University of Southern California, Los Angeles, CA 90089, USA
| | - Pinghui Feng
- Section of Infection and Immunity, Herman Ostrow School of Dentistry, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90089, USA
- Lead Contact
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13
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Nian Y, Iske J, Maenosono R, Minami K, Heinbokel T, Quante M, Liu Y, Azuma H, Yang J, Abdi R, Zhou H, Elkhal A, Tullius SG. Targeting age-specific changes in CD4 + T cell metabolism ameliorates alloimmune responses and prolongs graft survival. Aging Cell 2021; 20:e13299. [PMID: 33497523 PMCID: PMC7884034 DOI: 10.1111/acel.13299] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Revised: 11/16/2020] [Accepted: 12/08/2020] [Indexed: 12/12/2022] Open
Abstract
Age impacts alloimmunity. Effects of aging on T-cell metabolism and the potential to interfere with immunosuppressants have not been explored yet. Here, we dissected metabolic pathways of CD4+ and CD8+ T cells in aging and offer novel immunosuppressive targets. Upon activation, CD4+ T cells from old mice failed to exhibit adequate metabolic reprogramming resulting into compromised metabolic pathways, including oxidative phosphorylation (OXPHOS) and glycolysis. Comparable results were also observed in elderly human patients. Although glutaminolysis remained the dominant and age-independent source of mitochondria for activated CD4+ T cells, old but not young CD4+ T cells relied heavily on glutaminolysis. Treating young and old murine and human CD4+ T cells with 6-diazo-5-oxo-l-norleucine (DON), a glutaminolysis inhibitor resulted in significantly reduced IFN-γ production and compromised proliferative capacities specifically of old CD4+ T cells. Of translational relevance, old and young mice that had been transplanted with fully mismatched skin grafts and treated with DON demonstrated dampened Th1- and Th17-driven alloimmune responses. Moreover, DON diminished cytokine production and proliferation of old CD4+ T cells in vivo leading to a significantly prolonged allograft survival specifically in old recipients. Graft prolongation in young animals, in contrast, was only achieved when DON was applied in combination with an inhibition of glycolysis (2-deoxy-d-glucose, 2-DG) and OXPHOS (metformin), two alternative metabolic pathways. Notably, metabolic treatment had not been linked to toxicities. Remarkably, immunosuppressive capacities of DON were specific to CD4+ T cells as adoptively transferred young CD4+ T cells prevented immunosuppressive capacities of DON on allograft survival in old recipients. Depletion of CD8+ T cells did not alter transplant outcomes in either young or old recipients. Taken together, our data introduce an age-specific metabolic reprogramming of CD4+ T cells. Targeting those pathways offers novel and age-specific approaches for immunosuppression.
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Affiliation(s)
- Yeqi Nian
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Department of Urology Second Xiangya Hospital Central South University Changsha China
- Department of Kidney Transplantation Tianjin First Central Hospital Nankai University Tianjin China
| | - Jasper Iske
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Institute of Transplant Immunology Hannover Medical School Hannover Germany
| | - Ryoichi Maenosono
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Department of Urology Osaka Medical College Osaka Japan
| | - Koichiro Minami
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Department of Urology Osaka Medical College Osaka Japan
| | - Timm Heinbokel
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Department of Pathology Charité – Universitätsmedizin Berlin Berlin Germany
| | - Markus Quante
- Department of General, Visceral‐ and Transplant Surgery University Hospital Tübingen Tubingen Germany
| | - Yang Liu
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
- Institute of Hepatobiliary Diseases Zhongnan Hospital of Wuhan University Wuhan China
| | | | - Jinrui Yang
- Department of Urology Second Xiangya Hospital Central South University Changsha China
| | - Reza Abdi
- Renal Division Transplantation Research Center Brigham and Women's Hospital Harvard Medical School Boston MA USA
| | - Hao Zhou
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
| | - Abdallah Elkhal
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
| | - Stefan G. Tullius
- Division of Transplant Surgery and Transplant Surgery Research Laboratory Brigham and Women's Hospital Harvard Medical School Boston MA USA
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14
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Simonet JC, Foster MJ, Lynch EM, Kollman JM, Nicholas E, O'Reilly AM, Peterson JR. CTP synthase polymerization in germline cells of the developing Drosophila egg supports egg production. Biol Open 2020; 9:bio050328. [PMID: 32580972 PMCID: PMC7390647 DOI: 10.1242/bio.050328] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 06/16/2020] [Indexed: 01/19/2023] Open
Abstract
Polymerization of metabolic enzymes into micron-scale assemblies is an emerging mechanism for regulating their activity. CTP synthase (CTPS) is an essential enzyme in the biosynthesis of the nucleotide CTP and undergoes regulated and reversible assembly into large filamentous structures in organisms from bacteria to humans. The purpose of these assemblies is unclear. A major challenge to addressing this question has been the inability to abolish assembly without eliminating CTPS protein. Here we demonstrate that a recently reported point mutant in CTPS, Histidine 355A (H355A), prevents CTPS filament assembly in vivo and dominantly inhibits the assembly of endogenous wild-type CTPS in the Drosophila ovary. Expressing this mutant in ovarian germline cells, we show that disruption of CTPS assembly in early stage egg chambers reduces egg production. This effect is exacerbated in flies fed the glutamine antagonist 6-diazo-5-oxo-L-norleucine, which inhibits de novo CTP synthesis. These findings introduce a general approach to blocking the assembly of polymerizing enzymes without eliminating their catalytic activity and demonstrate a role for CTPS assembly in supporting egg production, particularly under conditions of limited glutamine metabolism.This article has an associated First Person interview with the first author of the paper.
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Affiliation(s)
- Jacqueline C Simonet
- Cancer Biology Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
| | - Maya J Foster
- Immersion Science Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
| | - Eric M Lynch
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Justin M Kollman
- Department of Biochemistry, University of Washington, Seattle, WA 98195, USA
| | - Emmanuelle Nicholas
- Cancer Biology Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
| | - Alana M O'Reilly
- Molecular Therapeutics Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
| | - Jeffrey R Peterson
- Cancer Biology Program, Fox Chase Cancer Center, 333 Cottman Avenue, Philadelphia, PA 19111, USA
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15
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Martin E, Minet N, Boschat AC, Sanquer S, Sobrino S, Lenoir C, de Villartay JP, Leite-de-Moraes M, Picard C, Soudais C, Bourne T, Hambleton S, Hughes SM, Wynn RF, Briggs TA, Patel S, Lawrence MG, Fischer A, Arkwright PD, Latour S. Impaired lymphocyte function and differentiation in CTPS1-deficient patients result from a hypomorphic homozygous mutation. JCI Insight 2020; 5:133880. [PMID: 32161190 PMCID: PMC7141395 DOI: 10.1172/jci.insight.133880] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 01/29/2020] [Indexed: 01/01/2023] Open
Abstract
Cytidine triphosphate (CTP) synthetase 1 (CTPS1) deficiency is caused by a unique homozygous frameshift splice mutation (c.1692-1G>C, p.T566Dfs26X). CTPS1-deficient patients display severe bacterial and viral infections. CTPS1 is responsible for CTP nucleotide de novo production involved in DNA/RNA synthesis. Herein, we characterized in depth lymphocyte defects associated with CTPS1 deficiency. Immune phenotyping performed in 7 patients showed absence or low numbers of mucosal-associated T cells, invariant NKT cells, memory B cells, and NK cells, whereas other subsets were normal. Proliferation and IL-2 secretion by T cells in response to TCR activation were markedly decreased in all patients, while other T cell effector functions were preserved. The CTPS1T566Dfs26X mutant protein was found to be hypomorphic, resulting in 80%-90% reduction of protein expression and CTPS activity in cells of patients. Inactivation of CTPS1 in a T cell leukemia fully abolished cell proliferation. Expression of CTPS1T566Dfs26X failed to restore proliferation of CTPS1-deficient leukemia cells to normal, except when forcing its expression to a level comparable to that of WT CTPS1. This indicates that CTPS1T566Dfs26X retained normal CTPS activity, and thus the loss of function of CTPS1T566Dfs26X is completely attributable to protein instability. This study supports that CTPS1 represents an attractive therapeutic target to selectively inhibit pathological T cell proliferation, including lymphoma.
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Affiliation(s)
- Emmanuel Martin
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
| | - Norbert Minet
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Anne-Claire Boschat
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
- Plateforme spectrométrie de masse, Imagine Institute, Paris, France
- Laboratoire de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants-Malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Sylvia Sanquer
- Laboratoire de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants-Malades, Assistance Publique-Hôpitaux de Paris (AP-HP), Paris, France
| | - Steicy Sobrino
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
| | - Christelle Lenoir
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
| | - Jean Pierre de Villartay
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
- Laboratory of Genome Dynamics in the Immune System, Inserm UMR 1163, Imagine Institute, Paris, France
| | - Maria Leite-de-Moraes
- Inserm UMR S1151 CNRS UMR 8253, Institut Necker Enfants Malades (INEM), Paris, France
| | - Capucine Picard
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
- Centre d’Etude des Déficits Immunitaires, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
- Department of Pediatric Immunology, Hematology and Rheumatology, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
| | - Claire Soudais
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
| | | | - Sophie Hambleton
- Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, United Kingdom
| | | | | | - Tracy A. Briggs
- Division of Evolution and Genomic Sciences, and
- Lydia Becker Institute of Immunology & Inflammation, University of Manchester, Manchester, United Kingdom
| | | | - Smita Patel
- John Radcliffe Hospital, Oxford, United Kingdom
| | - Monica G. Lawrence
- Division of Asthma, Allergy & Immunology, University of Virginia, Charlottesville, Virginia, USA
| | - Alain Fischer
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
- Department of Pediatric Immunology, Hematology and Rheumatology, Hôpital Necker-Enfants Malades, AP-HP, Paris, France
- Collège de France, Paris, France
- Inserm UMR 1163, Paris, France
| | | | - Sylvain Latour
- Laboratory of Lymphocyte Activation and Susceptibility to EBV infection, Inserm UMR 1163, Imagine Institute, Paris, France
- University Paris Descartes Sorbonne Paris Cité, Imagine Institute, Paris, France
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16
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Lynch EM, Kollman JM. Coupled structural transitions enable highly cooperative regulation of human CTPS2 filaments. Nat Struct Mol Biol 2019; 27:42-48. [PMID: 31873303 PMCID: PMC6954954 DOI: 10.1038/s41594-019-0352-5] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2019] [Accepted: 11/15/2019] [Indexed: 01/26/2023]
Abstract
Many enzymes assemble into defined oligomers, providing a mechanism for cooperatively regulating activity. Recent studies have described a mode of regulation in which enzyme activity is modulated by polymerization into large-scale filaments. Here we describe an ultrasensitive form of polymerization-based regulation employed by human CTP synthase 2 (CTPS2). Cryo-EM structures reveal that CTPS2 filaments dynamically switch between active and inactive forms in response to changes in substrate and product levels. Linking the conformational state of many CTPS2 subunits in a filament results in highly cooperative regulation, greatly exceeding the limits of cooperativity for the CTPS2 tetramer alone. The structures reveal a link between conformation and control of ammonia channeling between the enzyme’s active sites, and explain differences in regulation of human CTPS isoforms. This filament-based mechanism of enhanced cooperativity demonstrates how the widespread phenomenon of enzyme polymerization can be adapted to achieve different regulatory outcomes.
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Affiliation(s)
- Eric M Lynch
- Department of Biochemistry, University of Washington, Seattle, WA, USA
| | - Justin M Kollman
- Department of Biochemistry, University of Washington, Seattle, WA, USA.
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17
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Boschat AC, Minet N, Martin E, Barouki R, Latour S, Sanquer S. CTP synthetase activity assay by liquid chromatography tandem mass spectrometry in the multiple reaction monitoring mode. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:885-893. [PMID: 31524312 DOI: 10.1002/jms.4442] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 09/10/2019] [Accepted: 09/11/2019] [Indexed: 06/10/2023]
Abstract
Cytidine 5'-triphosphate synthetase (CTPS) is known to be a central enzyme in the de novo synthesis of CTP. We have recently demonstrated that a deficiency in CTPS1 is associated with an impaired capacity of activated lymphocytes to proliferate leading to a combined immunodeficiency disease. In order to better document its role in immunomodulation, we developed a method for measuring CTPS activity in human lymphocytes. Using liquid chromatography-mass spectrometry, we quantified CTPS activity by measuring CTP in cell lysates. A stable isotope analog of CTP served as internal standard. We characterized the kinetic parameters Vmax and Km of CTPS and verified that an inhibition of the enzyme activity was induced after 3-deazauridine (3DAU) treatment, a known inhibitor of CTPS. We then determined CTPS activity in healthy volunteers, in a family whose child displayed a homozygous mutation in CTPS1 gene and in patients who had developed or not a chronic lung allograft dysfunction (CLAD) after lung transplantation. Linearity of the CTP determination was observed up to 451 μmol/L, with accuracy in the 15% tolerance range. Michaelis-Menten kinetics for lysates of resting cells were Km =280±310 μmol/L for UTP, Vmax =83±20 pmol/min and, for lysates of activated PBMCs, Km =230±280 μmol/L for UTP, Vmax =379±90 pmol/min. Treatment by 3DAU and homozygous mutation in CTPS1 gene abolished the induction of CTPS activity associated with cell stimulation, and CTPS activity was significantly reduced in the patients who developed CLAD. We conclude that this test is suitable to reveal the involvement of CTPS alteration in immunodeficiency.
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Affiliation(s)
- Anne-Claire Boschat
- Plateforme de métabolomique, Institut Imagine, Université Paris Descartes, Paris, France
- INSERM UMR-S 1124, Centre Universitaire des Saints-Pères Université Paris Descartes, Paris, France
| | - Norbert Minet
- Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris, France
- INSERM UMR 1163, Université Paris Descartes, Institut Imagine, Paris, France
| | - Emmanuel Martin
- Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris, France
- INSERM UMR 1163, Université Paris Descartes, Institut Imagine, Paris, France
| | - Robert Barouki
- INSERM UMR-S 1124, Centre Universitaire des Saints-Pères Université Paris Descartes, Paris, France
- Plateforme de spectrométrie de masse, AP-HP.Centre, Hôpital Universitaire Necker-enfants malades, Paris, France
- Service de Biochimie Métabolomique et Protéomique, AP-HP.Centre, Hôpital Universitaire Necker-Enfants malades, Paris, France
| | - Sylvain Latour
- Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris, France
- INSERM UMR 1163, Université Paris Descartes, Institut Imagine, Paris, France
| | - Sylvia Sanquer
- INSERM UMR-S 1124, Centre Universitaire des Saints-Pères Université Paris Descartes, Paris, France
- Service de Biochimie Métabolomique et Protéomique, AP-HP.Centre, Hôpital Universitaire Necker-Enfants malades, Paris, France
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18
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Daumann M, Hickl D, Zimmer D, DeTar RA, Kunz HH, Möhlmann T. Characterization of filament-forming CTP synthases from Arabidopsis thaliana. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 96:316-328. [PMID: 30030857 PMCID: PMC6821390 DOI: 10.1111/tpj.14032] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 05/14/2018] [Accepted: 05/22/2018] [Indexed: 05/27/2023]
Abstract
Cytidine triphosphate (CTP) is essential for DNA, RNA and phospholipid biosynthesis. De novo synthesis is catalyzed by CTP synthases (CTPS). Arabidopsis encodes five CTPS isoforms that unanimously share conserved motifs found across kingdoms, suggesting all five are functional enzymes. Whereas CTPS1-4 are expressed throughout Arabidopsis tissues, CTPS5 reveals exclusive expression in developing embryos. CTPS activity and substrates affinities were determined for a representative plant enzyme on purified recombinant CTPS3 protein. As demonstrated in model organisms such as yeast, fruit fly and mammals, CTPS show the capacity to assemble into large filaments called cytoophidia. Transient expression of N- and C-terminal YFP-CTPS fusion proteins in Nicotiana benthamiana allowed to monitor such filament formation. Interestingly, CTPS1 and 2 always appeared as soluble proteins, whereas filaments were observed for CTPS3, 4 and 5 independent of the YFP-tag location. However, when similar constructs were expressed in Saccharomyces cerevisiae, no filaments were observed, pointing to a requirement for organism-specific factors in vivo. Indications for filament assembly were also obtained in vitro when recombinant CTPS3 protein was incubated in the presence of CTP. T-DNA-insertion mutants in four CTPS loci revealed no apparent phenotypical alteration. In contrast, CTPS2 T-DNA-insertion mutants did not produce homozygous progenies. An initial characterization of the CTPS protein family members from Arabidopsis is presented. We provide evidence for their involvement in nucleotide de novo synthesis and show that only three of the five CTPS isoforms were able to form filamentous structures in the transient tobacco expression system. This represents a striking difference from previous observations in prokaryotes, yeast, Drosophila and mammalian cells. This finding will be highly valuable to further understand the role of filament formation to regulate CTPS activity.
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Affiliation(s)
- Manuel Daumann
- Pflanzenphysiologie, Fachbereich Biologie, Universität Kaiserslautern, Erwin-Schrodinger-Straße, D-67663, Kaiserslautern, Germany, and
| | - Daniel Hickl
- Pflanzenphysiologie, Fachbereich Biologie, Universität Kaiserslautern, Erwin-Schrodinger-Straße, D-67663, Kaiserslautern, Germany, and
| | - David Zimmer
- Pflanzenphysiologie, Fachbereich Biologie, Universität Kaiserslautern, Erwin-Schrodinger-Straße, D-67663, Kaiserslautern, Germany, and
| | - Rachael A. DeTar
- School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA, 99164-4236, USA
| | - Hans-Henning Kunz
- School of Biological Sciences, Washington State University, PO Box 644236, Pullman, WA, 99164-4236, USA
| | - Torsten Möhlmann
- Pflanzenphysiologie, Fachbereich Biologie, Universität Kaiserslautern, Erwin-Schrodinger-Straße, D-67663, Kaiserslautern, Germany, and
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19
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Narvaez-Ortiz HY, Lopez AJ, Gupta N, Zimmermann BH. A CTP Synthase Undergoing Stage-Specific Spatial Expression Is Essential for the Survival of the Intracellular Parasite Toxoplasma gondii. Front Cell Infect Microbiol 2018; 8:83. [PMID: 29623259 PMCID: PMC5874296 DOI: 10.3389/fcimb.2018.00083] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Accepted: 02/28/2018] [Indexed: 01/17/2023] Open
Abstract
Cytidine triphosphate synthase catalyzes the synthesis of cytidine 5′-triphosphate (CTP) from uridine 5′-triphosphate (UTP), the final step in the production of cytidine nucleotides. CTP synthases also form filamentous structures of different morphologies known as cytoophidia, whose functions in most organisms are unknown. Here, we identified and characterized a novel CTP synthase (TgCTPS) from Toxoplasma gondii. We show that TgCTPS is capable of substituting for its counterparts in the otherwise lethal double mutant (ura7Δ ura8Δ) of Saccharomyces cerevisiae. Equally, recombinant TgCTPS purified from Escherichia coli encodes for a functional protein in enzyme assays. The epitope-tagged TgCTPS under the control of its endogenous promoter displays a punctate cytosolic distribution, which undergoes spatial reorganization to form foci or filament-like structures when the parasite switches from a nutrient-replete (intracellular) to a nutrient-scarce (extracellular) condition. An analogous phenotype is observed upon nutrient stress or after treatment with a glutamine analog, 6-diazo-5-oxo-L-norleucine (DON). The exposure of parasites to DON disrupts the lytic cycle, and the TgCTPS is refractory to a genetic deletion, suggesting an essential requirement of this enzyme for T. gondii. Not least, this study, together with previous studies, supports that CTP synthase can serve as a potent drug target, because the parasite, unlike human host cells, cannot compensate for the lack of CTP synthase activity.
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Affiliation(s)
| | - Andrea J Lopez
- Departamento de Ciencias Biologicas, Universidad de los Andes, Bogota, Colombia
| | - Nishith Gupta
- Department of Molecular Parasitology, Faculty of Life Sciences, Humboldt University, Berlin, Germany
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20
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Biophysical Analysis of Bacterial CTP Synthase Filaments Formed in the Presence of the Chemotherapeutic Metabolite Gemcitabine-5'-triphosphate. J Mol Biol 2018; 430:1201-1217. [PMID: 29501573 DOI: 10.1016/j.jmb.2018.02.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 02/16/2018] [Accepted: 02/23/2018] [Indexed: 11/21/2022]
Abstract
While enzyme activity is often regulated by a combination of substrate/effector availability and quaternary structure, many cytosolic enzymes may be further regulated through oligomerization into filaments. Cytidine-5'-triphosphate (CTP) synthase (CTPS) forms such filaments-a process that is promoted by the product CTP. The CTP analog and active chemotherapeutic metabolite gemcitabine-5'-triphosphate (dF-dCTP) is a potent inhibitor of CTPS; however, its effect on the enzyme's ability to form filaments is unknown. Alongside electron microscopy studies, dynamic light scattering showed that dF-dCTP induces Escherichia coli CTPS (EcCTPS) to form filaments in solution with lengths ≥30 nm in the presence of CTP or dF-dCTP. The substrate UTP blocks formation of filaments and effects their disassembly. EcCTPS variants were constructed to investigate the role of CTP-binding determinants in CTP- and dF-dCTP-dependent filament formation. Substitution of Glu 149 (i.e., E149D), which interacts with the ribose of CTP, caused reduced affinity for both CTP and dF-dCTP, and obviated filament formation. Phe 227 appears to interact with CTP through an edge-on interaction with the cytosine ring, yet the F227A and F227L variants bound CTP and dF-dCTP. F227A EcCTPS did not form filaments, while F227L EcCTPS formed shorter filaments in the presence of CTP or dF-dCTP. Hence, Phe 227 plays a role in filament formation, although replacement by a bulky hydrophobic amino acid is sufficient for limited filament formation. That dF-dCTP can induce filament formation highlights the fact that nucleotide analogs employed as chemotherapeutic agents may affect the filamentous states of enzymes and potentially alter their regulation in vivo.
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21
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Sakamoto K, Ishibashi Y, Adachi R, Matsumoto SI, Oki H, Kamada Y, Sogabe S, Zama Y, Sakamoto JI, Tani A. Identification of cytidine-5-triphosphate synthase1-selective inhibitory peptide from random peptide library displayed on T7 phage. Peptides 2017; 94:56-63. [PMID: 28676225 DOI: 10.1016/j.peptides.2017.06.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Revised: 06/22/2017] [Accepted: 06/26/2017] [Indexed: 01/22/2023]
Abstract
Cytidine triphosphate synthase 1 (CTPS1) is an enzyme expressed in activated lymphocytes that catalyzes the conversion of uridine triphosphate (UTP) to cytidine triphosphate (CTP) with ATP-dependent amination, using either L-glutamine or ammonia as the nitrogen source. Since CTP plays an important role in DNA/RNA synthesis, phospholipid synthesis, and protein sialyation, CTPS1-inhibition is expected to control lymphocyte proliferation and size expansion in inflammatory diseases. In contrast, CTPS2, an isozyme of CTPS1 possessing 74% amino acid sequence homology, is expressed in normal lymphocytes. Thus, CTPS1-selective inhibition is important to avoid undesirable side effects. Here, we report the discovery of CTpep-3: Ac-FRLGLLKAFRRLF-OH from random peptide libraries displayed on T7 phage, which exhibited CTPS1-selective binding with a KD value of 210nM in SPR analysis and CTPS1-selective inhibition with an IC50 value of 110nM in the enzyme assay. Furthermore, two fundamentally different approaches, enzyme inhibition assay and HDX-MS, provided the same conclusion that CTpep-3 acts by binding to the amidoligase (ALase) domain on CTPS1. To our knowledge, CTpep-3 is the first CTPS1-selective inhibitor.
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Affiliation(s)
- Kotaro Sakamoto
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan.
| | - Yoshihiro Ishibashi
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Ryutaro Adachi
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Shin-Ichi Matsumoto
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Hideyuki Oki
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Yusuke Kamada
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Satoshi Sogabe
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Yumi Zama
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Jun-Ichi Sakamoto
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
| | - Akiyoshi Tani
- Pharmaceutical Research Division, Takeda Pharmaceutical Company Limited, 26-1, Muraoka-Higashi 2-chome Fujisawa, Kanagawa 251-8555, Japan
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22
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Habrian C, Chandrasekhara A, Shahrvini B, Hua B, Lee J, Jesinghaus R, Barry R, Gitai Z, Kollman J, Baldwin EP. Inhibition of Escherichia coli CTP Synthetase by NADH and Other Nicotinamides and Their Mutual Interactions with CTP and GTP. Biochemistry 2016; 55:5554-5565. [PMID: 27571563 DOI: 10.1021/acs.biochem.6b00383] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
CTP synthetases catalyze the last step of pyrimidine biosynthesis and provide the sole de novo source of cytosine-containing nucleotides. As a central regulatory hub, they are regulated by ribonucleotide and enzyme concentration through ATP and UTP substrate availability, CTP product inhibition, GTP allosteric modification, and quaternary structural changes including the formation of CTP-inhibited linear polymers (filaments). Here, we demonstrate that nicotinamide redox cofactors are moderate inhibitors of Escherichia coli CTP synthetase (EcCTPS). NADH and NADPH are the most potent, and the primary inhibitory determinant is the reduced nicotinamide ring. Although nicotinamide inhibition is noncompetitive with substrates, it apparently enhances CTP product feedback inhibition and GTP allosteric regulation. Further, CTP and GTP also enhance each other's effects, consistent with the idea that NADH, CTP, and GTP interact with a common intermediate enzyme state. A filament-blocking mutation that reduces CTP inhibitory effects also reduced inhibition by GTP but not NADH. Protein-concentration effects on GTP inhibition suggest that, like CTP, GTP preferentially binds to the filament. All three compounds display nearly linear dose-dependent inhibition, indicating a complex pattern of cooperative interactions between binding sites. The apparent synergy between inhibitors, in consideration with physiological nucleotide concentrations, points to metabolically relevant inhibition by nicotinamides, and implicates cellular redox state as a regulator of pyrimidine biosynthesis.
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Affiliation(s)
- Chris Habrian
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States.,Biophysics Graduate Program, University of California, Berkeley , Berkeley, California 94720, United States
| | - Adithi Chandrasekhara
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States.,Process Development Rotation Program, Genentech Inc. , 1 DNA Way, South San Francisco, California 94080, United States
| | - Bita Shahrvini
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States
| | - Brian Hua
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States.,Department of Biology, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States
| | - Jason Lee
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States.,Drexel University College of Medicine , Philadelphia, Pennsylvania 19129, United States.,Kaiser Permanente , Sacramento, California 95823, United States
| | - Roger Jesinghaus
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States
| | - Rachael Barry
- Department of Molecular Biology, Princeton University , Princeton, New Jersey 08544, United States.,Department of Cellular and Molecular Medicine, University of California, San Diego , La Jolla, California 92903, United States
| | - Zemer Gitai
- Department of Molecular Biology, Princeton University , Princeton, New Jersey 08544, United States
| | - Justin Kollman
- Department of Biochemistry, University of Washington , Seattle, Washington 98195, United States
| | - Enoch P Baldwin
- Department of Molecular and Cellular Biology, University of California, Davis , Davis, California 95616, United States
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23
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Tunc-Ozdemir M, Urano D, Jaiswal DK, Clouse SD, Jones AM. Direct Modulation of Heterotrimeric G Protein-coupled Signaling by a Receptor Kinase Complex. J Biol Chem 2016; 291:13918-13925. [PMID: 27235398 DOI: 10.1074/jbc.c116.736702] [Citation(s) in RCA: 50] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Indexed: 01/17/2023] Open
Abstract
Plants and some protists have heterotrimeric G protein complexes that activate spontaneously without canonical G protein-coupled receptors (GPCRs). In Arabidopsis, the sole 7-transmembrane regulator of G protein signaling 1 (AtRGS1) modulates the G protein complex by keeping it in the resting state (GDP-bound). However, it remains unknown how a myriad of biological responses is achieved with a single G protein modulator. We propose that in complete contrast to G protein activation in animals, plant leucine-rich repeat receptor-like kinases (LRR RLKs), not GPCRs, provide this discrimination through phosphorylation of AtRGS1 in a ligand-dependent manner. G protein signaling is directly activated by the pathogen-associated molecular pattern flagellin peptide 22 through its LRR RLK, FLS2, and co-receptor BAK1.
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Affiliation(s)
- Meral Tunc-Ozdemir
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Daisuke Urano
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Dinesh Kumar Jaiswal
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599
| | - Steven D Clouse
- Department of Horticultural Science, North Carolina State University, Raleigh, North Carolina 27695-7609
| | - Alan M Jones
- Department of Biology, University of North Carolina, Chapel Hill, North Carolina 27599; Department of Pharmacology, University of North Carolina, Chapel Hill, North Carolina 27599.
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24
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Aughey GN, Grice SJ, Shen QJ, Xu Y, Chang CC, Azzam G, Wang PY, Freeman-Mills L, Pai LM, Sung LY, Yan J, Liu JL. Nucleotide synthesis is regulated by cytoophidium formation during neurodevelopment and adaptive metabolism. Biol Open 2014; 3:1045-56. [PMID: 25326513 PMCID: PMC4232762 DOI: 10.1242/bio.201410165] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The essential metabolic enzyme CTP synthase (CTPsyn) can be compartmentalised to form an evolutionarily-conserved intracellular structure termed the cytoophidium. Recently, it has been demonstrated that the enzymatic activity of CTPsyn is attenuated by incorporation into cytoophidia in bacteria and yeast cells. Here we demonstrate that CTPsyn is regulated in a similar manner in Drosophila tissues in vivo. We show that cytoophidium formation occurs during nutrient deprivation in cultured cells, as well as in quiescent and starved neuroblasts of the Drosophila larval central nervous system. We also show that cytoophidia formation is reversible during neurogenesis, indicating that filament formation regulates pyrimidine synthesis in a normal developmental context. Furthermore, our global metabolic profiling demonstrates that CTPsyn overexpression does not significantly alter CTPsyn-related enzymatic activity, suggesting that cytoophidium formation facilitates metabolic stabilisation. In addition, we show that overexpression of CTPsyn only results in moderate increase of CTP pool in human stable cell lines. Together, our study provides experimental evidence, and a mathematical model, for the hypothesis that inactive CTPsyn is incorporated into cytoophidia.
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Affiliation(s)
- Gabriel N Aughey
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Stuart J Grice
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Qing-Ji Shen
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Yichi Xu
- CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Chia-Chun Chang
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan, Republic of China
| | - Ghows Azzam
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Pei-Yu Wang
- Department of Biochemistry, College of Medicine, Chang Gung University, Tao-Yuan, 333, Taiwan, Republic of China Molecular Medicine Research Center, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan, Republic of China
| | - Luke Freeman-Mills
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
| | - Li-Mei Pai
- Department of Biochemistry, College of Medicine, Chang Gung University, Tao-Yuan, 333, Taiwan, Republic of China Molecular Medicine Research Center, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan, Republic of China Graduate Institute of Biomedical Sciences, College of Medicine, Chang Gung University, Tao-Yuan 333, Taiwan, Republic of China
| | - Li-Ying Sung
- Institute of Biotechnology, National Taiwan University, Taipei 106, Taiwan, Republic of China Agricultural Biotechnology Research Center, Academia Sinica, Taipei 115, Taiwan, Republic of China
| | - Jun Yan
- CAS-MPG Partner Institute for Computational Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ji-Long Liu
- Medical Research Council Functional Genomics Unit, Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, United Kingdom
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25
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Zhu M, Sun W, Wang Y, Meng J, Zhang D, Guo T, Ouyang P, Ying H, Xie J. Engineered cytidine triphosphate synthetase with reduced product inhibition. Protein Eng Des Sel 2014; 27:225-33. [PMID: 24902851 DOI: 10.1093/protein/gzu019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Cytidine triphosphate (CTP) synthetase (CTPS) (EC number 6.3.4.2) is a key enzyme involved in de novo synthesis of CTP. It catalyzes the rate-limiting step of the process due to the product inhibition effects on the enzyme. In this study, a novel CTPS from Corynebacterium glutamicum ATCC 13032 (CgCTPS) was cloned, expressed and characterized. A series of mutagenesis in its N-terminal ammonia ligase (ALase) domain was performed in order to reduce CTP product inhibition. All single mutation variants (D160E, E162A, E168K) lowered product inhibition by lowering the enzyme's binding affinity for CTP. The homology model of CgCTPS showed that D160E mutant caused steric hindrance for the pyrimidine ring of CTP stacking, E162A disrupted the hydrogen bond between CTP ribose and side chain and D168K caused minor localized structure perturbations of CTP binding pocket. The triple mutant of CTPS (D160E-E162A-E168K) with halved Km, doubled Vmax and the 23.5-fold increased IC50 for CTP shows a potential for use in industrial-scale CTP production by its better performance in enzyme kinetics and product inhibition.
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Affiliation(s)
- Mengzhu Zhu
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Wujin Sun
- Joint Department of Biomedical Engineering, The University of North Carolina at Chapel Hill and North Carolina State University, Raleigh 27695, USA
| | - Yan Wang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Jie Meng
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Dalu Zhang
- International Cooperation Division, China National Center for Biotechnology Development, Beijing 100036, People's Republic of China
| | - Ting Guo
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China Guangzhou Sugarcane Industry Research Institute, Guangzhou 510316, People's Republic of China
| | - Pingkai Ouyang
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Hanjie Ying
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China
| | - Jingjing Xie
- State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing 211816, People's Republic of China National Engineering Technique Research Center for Biotechnology, Nanjing Tech University, Nanjing 211816, People's Republic of China Present address: College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, South Puzhu Road 30, Nanjing 211816, People's Republic of China
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26
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27
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Martin E, Palmic N, Sanquer S, Lenoir C, Hauck F, Mongellaz C, Fabrega S, Nitschké P, Esposti MD, Schwartzentruber J, Taylor N, Majewski J, Jabado N, Wynn RF, Picard C, Fischer A, Arkwright PD, Latour S. CTP synthase 1 deficiency in humans reveals its central role in lymphocyte proliferation. Nature 2014; 510:288-92. [PMID: 24870241 PMCID: PMC6485470 DOI: 10.1038/nature13386] [Citation(s) in RCA: 142] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Accepted: 04/22/2014] [Indexed: 12/18/2022]
Abstract
Lymphocyte functions triggered by antigen recognition and co-stimulation signals are associated with a rapid and intense cell division, and hence with metabolism adaptation. The nucleotide cytidine 5' triphosphate (CTP) is a precursor required for the metabolism of DNA, RNA and phospholipids. CTP originates from two sources: a salvage pathway and a de novo synthesis pathway that depends on two enzymes, the CTP synthases (or synthetases) 1 and 2 (CTPS1 with CTPS2); the respective roles of these two enzymes are not known. CTP synthase activity is a potentially important step for DNA synthesis in lymphocytes. Here we report the identification of a loss-of-function homozygous mutation (rs145092287) in CTPS1 in humans that causes a novel and life-threatening immunodeficiency, characterized by an impaired capacity of activated T and B cells to proliferate in response to antigen receptor-mediated activation. In contrast, proximal and distal T-cell receptor (TCR) signalling events and responses were only weakly affected by the absence of CTPS1. Activated CTPS1-deficient cells had decreased levels of CTP. Normal T-cell proliferation was restored in CTPS1-deficient cells by expressing wild-type CTPS1 or by addition of exogenous CTP or its nucleoside precursor, cytidine. CTPS1 expression was found to be low in resting T cells, but rapidly upregulated following TCR activation. These results highlight a key and specific role of CTPS1 in the immune system by its capacity to sustain the proliferation of activated lymphocytes during the immune response. CTPS1 may therefore represent a therapeutic target of immunosuppressive drugs that could specifically dampen lymphocyte activation.
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Affiliation(s)
- Emmanuel Martin
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Noé Palmic
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Sylvia Sanquer
- Laboratoire de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Christelle Lenoir
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Fabian Hauck
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France
| | - Cédric Mongellaz
- Hematopoiesis and Immunotherapy, CNRS-UMR 5535, Institut de Génétique Moléculaire de Montpellier, Montpellier 34293, France
| | - Sylvie Fabrega
- 1] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France [2] Plateforme Vecteurs Viraux et Transfert de Gènes, IFR94, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Patrick Nitschké
- 1] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France [2] Service de Bioinformatique, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Mauro Degli Esposti
- 1] University of Manchester, Royal Manchester Children's Hospital, Manchester M13 0WL, UK [2] Italian Institute of Technology, Genoa 16163, Italy
| | | | - Naomi Taylor
- Hematopoiesis and Immunotherapy, CNRS-UMR 5535, Institut de Génétique Moléculaire de Montpellier, Montpellier 34293, France
| | - Jacek Majewski
- McGill University and Genome Québec Innovation Centre, Montréal H3A 0G1, Canada
| | - Nada Jabado
- 1] McGill University and Genome Québec Innovation Centre, Montréal H3A 0G1, Canada [2] Department of Pediatrics, McGill University Health Center Research Institute, Montréal H3H 1P3, Canada
| | - Robert F Wynn
- University of Manchester, Royal Manchester Children's Hospital, Manchester M13 0WL, UK
| | - Capucine Picard
- 1] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France [2] Centre d'Etude des Déficits Immunitaires, Hôpital Necker Enfants-Malades, AP-HP, Paris 75015, France [3] Laboratoire Génétique Humaine des Maladies Infectieuses, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France
| | - Alain Fischer
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France [3] Unité d'Immunologie et Hématologie Pédiatrique, Assistance Publique-Hôpitaux de Paris (AP-HP), Hôpital Necker Enfants-Malades, Paris 75015, France [4] Collège de France, Paris 75005, France
| | - Peter D Arkwright
- 1] University of Manchester, Royal Manchester Children's Hospital, Manchester M13 0WL, UK [2]
| | - Sylvain Latour
- 1] Laboratoire Activation Lymphocytaire et Susceptibilité à l'EBV, INSERM UMR 1163, Hôpital Necker Enfants-Malades, Paris 75015, France [2] Université Paris Descartes Sorbonne Paris Cité, Institut Imagine, Paris 75015, France [3] Laboratoire de Biochimie Métabolomique et Protéomique, Hôpital Necker Enfants-Malades, Paris 75015, France [4]
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Strulson CA, Yennawar NH, Rambo RP, Bevilacqua PC. Molecular crowding favors reactivity of a human ribozyme under physiological ionic conditions. Biochemistry 2013; 52:8187-97. [PMID: 24187989 PMCID: PMC3882164 DOI: 10.1021/bi400816s] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In an effort to relate RNA folding to function under cellular-like conditions, we monitored the self-cleavage reaction of the human hepatitis delta virus-like CPEB3 ribozyme in the background of physiological ionic concentrations and various crowding and cosolute agents. We found that at physiological free Mg(2+) concentrations (∼0.1-0.5 mM), both crowders and cosolutes stimulate the rate of self-cleavage, up to ∼6-fold, but that in 10 mM Mg(2+) (conditions widely used for in vitro ribozyme studies) these same additives have virtually no effect on the self-cleavage rate. We further observe a dependence of the self-cleavage rate on crowder size, wherein the level of rate stimulation is diminished for crowders larger than the size of the unfolded RNA. Monitoring effects of crowding and cosolute agents on rates in biological amounts of urea revealed additive-promoted increases at both low and high Mg(2+) concentrations, with a maximal stimulation of more than 10-fold and a rescue of the rate to its urea-free values. Small-angle X-ray scattering experiments reveal a structural basis for this stimulation in that higher-molecular weight crowding agents favor a more compact form of the ribozyme in 0.5 mM Mg(2+) that is essentially equivalent to the form under standard ribozyme conditions of 10 mM Mg(2+) without a crowder. This finding suggests that at least a portion of the rate enhancement arises from favoring the native RNA tertiary structure. We conclude that cellular-like crowding supports ribozyme reactivity by favoring a compact form of the ribozyme, but only under physiological ionic and cosolute conditions.
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Affiliation(s)
- Christopher A. Strulson
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
- Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Neela H. Yennawar
- Huck Institutes of the Life Sciences, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Robert P. Rambo
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, 94720
| | - Philip C. Bevilacqua
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
- Center for RNA Molecular Biology, The Pennsylvania State University, University Park, Pennsylvania 16802
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Stobbe MD, Swertz MA, Thiele I, Rengaw T, van Kampen AHC, Moerland PD. Consensus and conflict cards for metabolic pathway databases. BMC SYSTEMS BIOLOGY 2013; 7:50. [PMID: 23803311 PMCID: PMC3703255 DOI: 10.1186/1752-0509-7-50] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/23/2012] [Accepted: 06/20/2013] [Indexed: 01/04/2023]
Abstract
Background The metabolic network of H. sapiens and many other organisms is described in multiple pathway databases. The level of agreement between these descriptions, however, has proven to be low. We can use these different descriptions to our advantage by identifying conflicting information and combining their knowledge into a single, more accurate, and more complete description. This task is, however, far from trivial. Results We introduce the concept of Consensus and Conflict Cards (C2Cards) to provide concise overviews of what the databases do or do not agree on. Each card is centered at a single gene, EC number or reaction. These three complementary perspectives make it possible to distinguish disagreements on the underlying biology of a metabolic process from differences that can be explained by different decisions on how and in what detail to represent knowledge. As a proof-of-concept, we implemented C2CardsHuman, as a web application http://www.molgenis.org/c2cards, covering five human pathway databases. Conclusions C2Cards can contribute to ongoing reconciliation efforts by simplifying the identification of consensus and conflicts between pathway databases and lowering the threshold for experts to contribute. Several case studies illustrate the potential of the C2Cards in identifying disagreements on the underlying biology of a metabolic process. The overviews may also point out controversial biological knowledge that should be subject of further research. Finally, the examples provided emphasize the importance of manual curation and the need for a broad community involvement.
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Affiliation(s)
- Miranda D Stobbe
- Bioinformatics Laboratory, Academic Medical Center, University of Amsterdam, PO Box 22700, Amsterdam 1100 DE, the Netherlands
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Activation and inhibition of CTP synthase from Trypanosoma brucei, the causative agent of African sleeping sickness. Bioorg Med Chem Lett 2011; 21:5188-90. [DOI: 10.1016/j.bmcl.2011.07.054] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2011] [Revised: 07/13/2011] [Accepted: 07/13/2011] [Indexed: 11/19/2022]
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