1
|
Moyer DC, Reimertz J, Segrè D, Fuxman Bass JI. Semi-Automatic Detection of Errors in Genome-Scale Metabolic Models. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.06.24.600481. [PMID: 38979177 PMCID: PMC11230171 DOI: 10.1101/2024.06.24.600481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/10/2024]
Abstract
Background Genome-Scale Metabolic Models (GSMMs) are used for numerous tasks requiring computational estimates of metabolic fluxes, from predicting novel drug targets to engineering microbes to produce valuable compounds. A key limiting step in most applications of GSMMs is ensuring their representation of the target organism's metabolism is complete and accurate. Identifying and visualizing errors in GSMMs is complicated by the fact that they contain thousands of densely interconnected reactions. Furthermore, many errors in GSMMs only become apparent when considering pathways of connected reactions collectively, as opposed to examining reactions individually. Results We present Metabolic Accuracy Check and Analysis Workflow (MACAW), a collection of algorithms for detecting errors in GSMMs. The relative frequencies of errors we detect in manually curated GSMMs appear to reflect the different approaches used to curate them. Changing the method used to automatically create a GSMM from a particular organism's genome can have a larger impact on the kinds of errors in the resulting GSMM than using the same method with a different organism's genome. Our algorithms are particularly capable of identifying errors that are only apparent at the pathway level, including loops, and nontrivial cases of dead ends. Conclusions MACAW is capable of identifying inaccuracies of varying severity in a wide range of GSMMs. Correcting these errors can measurably improve the predictive capacity of a GSMM. The relative prevalence of each type of error we identify in a large collection of GSMMs could help shape future efforts for further automation of error correction and GSMM creation.
Collapse
|
2
|
Immunogenic Cell Death, DAMPs and Prothymosin α as a Putative Anticancer Immune Response Biomarker. Cells 2022; 11:cells11091415. [PMID: 35563721 PMCID: PMC9102069 DOI: 10.3390/cells11091415] [Citation(s) in RCA: 32] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2022] [Revised: 04/13/2022] [Accepted: 04/13/2022] [Indexed: 12/13/2022] Open
Abstract
The new and increasingly studied concept of immunogenic cell death (ICD) revealed a previously unknown perspective of the various regulated cell death (RCD) modalities, elucidating their immunogenic properties and rendering obsolete the notion that immune stimulation is solely the outcome of necrosis. A distinct characteristic of ICD is the release of danger-associated molecular patterns (DAMPs) by dying and/or dead cells. Thus, several members of the DAMP family, such as the well-characterized heat shock proteins (HSPs) HSP70 and HSP90, the high-mobility group box 1 protein and calreticulin, and the thymic polypeptide prothymosin α (proTα) and its immunoreactive fragment proTα(100–109), are being studied as potential diagnostic tools and/or possible therapeutic agents. Here, we present the basic aspects and mechanisms of both ICD and other immunogenic RCD forms; denote the role of DAMPs in ICD; and further exploit the relevance of human proTα and proTα(100–109) in ICD, highlighting their possible clinical applications. Furthermore, we present the preliminary results of our in vitro studies, which show a direct correlation between the concentration of proTα/proTα(100–109) and the levels of cancer cell apoptosis, induced by anticancer agents and γ-radiation.
Collapse
|
3
|
Case NT, Duah K, Larsen B, Wong CJ, Gingras AC, O'Meara TR, Robbins N, Veri AO, Whitesell L, Cowen LE. The macrophage-derived protein PTMA induces filamentation of the human fungal pathogen Candida albicans. Cell Rep 2021; 36:109584. [PMID: 34433036 PMCID: PMC8454912 DOI: 10.1016/j.celrep.2021.109584] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 06/23/2021] [Accepted: 07/29/2021] [Indexed: 12/01/2022] Open
Abstract
Evasion of killing by immune cells is crucial for fungal survival in the host. For the human fungal pathogen Candida albicans, internalization by macrophages induces a transition from yeast to filaments that promotes macrophage death and fungal escape. Nutrient deprivation, alkaline pH, and oxidative stress have been implicated as triggers of intraphagosomal filamentation; however, the impact of other host-derived factors remained unknown. Here, we show that lysates prepared from macrophage-like cell lines and primary macrophages robustly induce C. albicans filamentation. Enzymatic treatment of lysate implicates a phosphorylated protein, and bioactivity-guided fractionation coupled to mass spectrometry identifies the immunomodulatory phosphoprotein PTMA as a candidate trigger of C. albicans filamentation. Immunoneutralization of PTMA within lysate abolishes its activity, strongly supporting PTMA as a filament-inducing component of macrophage lysate. Adding to the known repertoire of physical factors, this work implicates a host protein in the induction of C. albicans filamentation within immune cells. The human fungal pathogen Candida albicans filaments within host macrophages, enabling its escape. Case et al. demonstrate that lysates prepared from macrophage-like cell lines and primary macrophages induce C. albicans filamentation and implicate the immunomodulatory protein prothymosin alpha (PTMA) as a trigger of filamentation produced by host immune cells.
Collapse
Affiliation(s)
- Nicola T Case
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Kwamaa Duah
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Brett Larsen
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Cassandra J Wong
- Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Anne-Claude Gingras
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada; Lunenfeld-Tanenbaum Research Institute, Sinai Health System, Toronto, ON M5G 1X5, Canada
| | - Teresa R O'Meara
- Department of Microbiology and Immunology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Nicole Robbins
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Amanda O Veri
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Luke Whitesell
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Leah E Cowen
- Department of Molecular Genetics, University of Toronto, Toronto, ON M5S 1A8, Canada.
| |
Collapse
|
4
|
Karachaliou CE, Kalbacher H, Voelter W, Tsitsilonis OE, Livaniou E. In Vitro Immunodetection of Prothymosin Alpha in Normal and Pathological Conditions. Curr Med Chem 2020; 27:4840-4854. [PMID: 31389310 DOI: 10.2174/0929867326666190807145212] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2019] [Revised: 05/20/2019] [Accepted: 07/22/2019] [Indexed: 02/06/2023]
Abstract
Prothymosin alpha (ProTα) is a highly acidic polypeptide, ubiquitously expressed in almost all mammalian cells and tissues and consisting of 109 amino acids in humans. ProTα is known to act both, intracellularly, as an anti-apoptotic and proliferation mediator, and extracellularly, as a biologic response modifier mediating immune responses similar to molecules termed as "alarmins". Antibodies and immunochemical techniques for ProTα have played a leading role in the investigation of the biological role of ProTα, several aspects of which still remain unknown and contributed to unraveling the diagnostic and therapeutic potential of the polypeptide. This review deals with the so far reported antibodies along with the related immunodetection methodology for ProTα (immunoassays as well as immunohistochemical, immunocytological, immunoblotting, and immunoprecipitation techniques) and its application to biological samples of interest (tissue extracts and sections, cells, cell lysates and cell culture supernatants, body fluids), in health and disease states. In this context, literature information is critically discussed, and some concluding remarks are presented.
Collapse
Affiliation(s)
- Chrysoula-Evangelia Karachaliou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", 15310 Agia Paraskevi, Athens, Greece
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tuebingen, 72076 Tuebingen, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tuebingen, 72076 Tuebingen, Germany
| | - Ourania E Tsitsilonis
- Department of Biology, National and Kapodistrian University of Athens, 15701 Athens, Greece
| | - Evangelia Livaniou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", 15310 Agia Paraskevi, Athens, Greece
| |
Collapse
|
5
|
Karachaliou CE, Kostopoulos IV, Vassilakopoulou V, Klimentzou P, Paravatou-Petsotas M, Voelter W, Kalbacher H, Zikos C, Tsitsilonis O, Livaniou E. Development of a specific IgY-based ELISA for prothymosin alpha, a bioactive polypeptide with diagnostic and therapeutic potential. Heliyon 2019; 5:e02616. [PMID: 31720448 PMCID: PMC6838902 DOI: 10.1016/j.heliyon.2019.e02616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 09/10/2019] [Accepted: 10/04/2019] [Indexed: 01/15/2023] Open
Abstract
Prothymosin alpha (ProTα) is a highly conserved polypeptide (109 amino acids in humans) with diagnostic and therapeutic potential; ProTα exerts intra- and extra-cellular biological functions associated with cell proliferation, apoptosis and immune regulation, while it has been suggested to act as a damage-associated molecular pattern (DAMP) or alarmin. In this work, chicken polyclonal anti-ProTα antibodies that had been developed several years ago were immunochemically evaluated and proven to retain immunoreactivity for ProTα, with remarkable thermal and pH stability. Moreover, the antibodies showed practically no cross-reactivity with a series of ProTα-fragments, eventually intracellularly produced -such as ProTα[1-28] (also known as Tα1) and ProTα[100-109], which exert per se biological activity and might be present in biological samples along with the intact molecule, being therefore highly specific for whole-length ProTα. Based on the above antibodies (IgYs-3e), a highly specific competitive ProTα-ELISA with well-studied analytical characteristics (intra- and inter-assay CVs: ≤5% and ≤12%, respectively, limit of detection: 2.1 ng/mL, recovery: 88–104%) was developed. The new ProTα-ELISA was applied to the analysis of supernatants of HeLa cells driven to necrosis; intact ProTα was measured in cell culture supernatants, at levels that seemed to depend on % cell necrosis.
Collapse
Affiliation(s)
- Chrysoula-Evangelia Karachaliou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| | - Ioannis V Kostopoulos
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Vyronia Vassilakopoulou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| | - Persefoni Klimentzou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| | - Maria Paravatou-Petsotas
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen, Germany
| | - Christos Zikos
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| | - Ourania Tsitsilonis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Evangelia Livaniou
- Institute of Nuclear & Radiological Sciences and Technology, Energy & Safety (INRASTES), National Centre for Scientific Research "Demokritos", Athens, Greece
| |
Collapse
|
6
|
Samara P, Miriagou V, Zachariadis M, Mavrofrydi O, Promponas VJ, Dedos SG, Papazafiri P, Kalbacher H, Voelter W, Tsitsilonis O. A fragment of the alarmin prothymosin α as a novel biomarker in murine models of bacteria-induced sepsis. Oncotarget 2018; 8:48635-48649. [PMID: 28611290 PMCID: PMC5564713 DOI: 10.18632/oncotarget.18149] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 04/17/2017] [Indexed: 12/21/2022] Open
Abstract
Sepsis is a life-threatening condition that requires urgent care. Thus, the identification of specific and sensitive biomarkers for its early diagnosis and management are of clinical importance. The alarmin prothymosin alpha (proTα) and its decapeptide proTα(100-109) are immunostimulatory peptides related to cell death. In this study, we generated bacterial models of sepsis in mice using two Klebsiella pneumoniae strains (L-78 and ATCC 43816) and monitored sepsis progression using proTα(100-109) as a biomarker. Serum concentration of proTα(100-109) gradually increased as sepsis progressed in mice infected with L-78, a strain which, unlike ATCC 43816, was phagocytosed by monocytes/macrophages. Analysis of splenocytes from L-78-infected animals revealed that post-infection spleen monocytes/macrophages were gradually driven to caspase-3-mediated apoptosis. These results were verified in vitro in L-78-infected human monocytes/macrophages. Efficient phagocytosis of L-78 by monocytes stimulated their apoptosis and the concentration of proTα(100-109) in culture supernatants increased. Human macrophages strongly phagocytosed L-78, but resisted cell death. This is the first report suggesting that high levels of proTα(100-109) correlate, both in vitro and in vivo, with increased percentages of cell apoptosis. Moreover, we showed that low levels of proTα(100-109) early post-infection likely correlate with sepsis resolution and thus, the decapeptide could eventually serve as an early surrogate biomarker for predicting bacteria-induced sepsis outcome.
Collapse
Affiliation(s)
- Pinelopi Samara
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Vivi Miriagou
- Laboratory of Bacteriology, Hellenic Pasteur Institute, Athens, Greece
| | - Michael Zachariadis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece.,Institute of Biosciences and Applications, National Center for Scientific Research "Demokritos", Agia Paraskevi, Athens, Greece
| | - Olga Mavrofrydi
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Vasilis J Promponas
- Bioinformatics Research Laboratory, Department of Biological Sciences, University of Cyprus, Nicosia, Cyprus
| | - Skarlatos G Dedos
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Panagiota Papazafiri
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tübingen, Tübingen, Germany
| | - Ourania Tsitsilonis
- Department of Biology, National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
7
|
Fan Y, Zhang Q, Li H, Cheng Z, Li X, Chen Y, Shen Y, Wang L, Song G, Qian L. Peptidomics Analysis of Transient Regeneration in the Neonatal Mouse Heart. J Cell Biochem 2017; 118:2828-2840. [PMID: 28198139 DOI: 10.1002/jcb.25933] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2016] [Accepted: 02/10/2017] [Indexed: 12/30/2022]
Abstract
Neonatal mouse hearts have completely regenerative capability after birth, but the ability to regenerate rapidly lost after 7 days, the mechanism has not been clarified. Previous studies have shown that mRNA profile of adult mouse changed greatly compared to neonatal mouse. So far, there is no research of peptidomics related to heart regeneration. In order to explore the changes of proteins, enzymes, and peptides related to the transient regeneration, we used comparative petidomics technique to compare the endogenous peptides in the mouse heart of postnatal 1 and 7 days. In final, we identified 236 differentially expressed peptides, 169 of which were upregulated and 67 were downregulated in the postnatal 1 day heart, and also predicted 36 functional peptides associated with transient regeneration. The predicted 36 candidate peptides are located in the important domains of precursor proteins and/or contain the post-transcriptional modification (PTM) sites, which are involved in the biological processes of cardiac development, cardiac muscle disease, cell proliferation, necrosis, and apoptosis. In conclusion, for the first time, we compared the peptidomics profiles of neonatal heart between postnatal 1 day and postnatal 7 day. This study provides a new direction and an important basis for the mechanism research of transient regeneration in neonatal heart. J. Cell. Biochem. 118: 2828-2840, 2017. © 2017 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Yi Fan
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Qijun Zhang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Hua Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Zijie Cheng
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Xing Li
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Yumei Chen
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Yahui Shen
- Departments of Cardiology, Taizhou People's Hospital, Taizhou 225300, China
| | - Liansheng Wang
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| | - Guixian Song
- Departments of Cardiology, Taizhou People's Hospital, Taizhou 225300, China
| | - Lingmei Qian
- Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210029, China
| |
Collapse
|
8
|
Páez-Franco JC, González-Sánchez I, Gutiérrez-Nájera NA, Valencia-Turcotte LG, Lira-Rocha A, Cerbón MA, Rodríguez-Sotres R. Proteomic Profiling Reveals the Induction of UPR in Addition to DNA Damage Response in HeLa Cells Treated With the Thiazolo[5,4-b]Quinoline Derivative D3ClP. J Cell Biochem 2016; 118:1164-1173. [DOI: 10.1002/jcb.25753] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2016] [Accepted: 09/28/2016] [Indexed: 12/27/2022]
Affiliation(s)
- José Carlos Páez-Franco
- Departamento de Bioquímica; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Ignacio González-Sánchez
- Departamento de Biología; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Nora A. Gutiérrez-Nájera
- Consorcio de Estructura de Proteínas; Instituto Nacional de Medicina Genómica; Mexico City Mexico
| | - Lilián G. Valencia-Turcotte
- Departamento de Bioquímica; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Alfonso Lira-Rocha
- Departamento de Farmacia; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
| | - Marco A. Cerbón
- Departamento de Biología; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
- Unidad de Investigación en Reproducción Humana; Instituto Nacional de Perinatología; Mexico City Mexico
| | - Rogelio Rodríguez-Sotres
- Departamento de Bioquímica; Facultad de Química; Universidad Nacional Autónoma de México; Mexico City Mexico
| |
Collapse
|
9
|
Kijogi CM, Khayeka-Wandabwa C, Sasaki K, Tanaka Y, Kurosu H, Matsunaga H, Ueda H. Subcellular dissemination of prothymosin alpha at normal physiology: immunohistochemical vis-a-vis western blotting perspective. BMC PHYSIOLOGY 2016; 16:2. [PMID: 26932824 PMCID: PMC4774093 DOI: 10.1186/s12899-016-0021-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/22/2015] [Accepted: 02/16/2016] [Indexed: 11/10/2022]
Abstract
BACKGROUND The cell type, cell status and specific localization of Prothymosin α (PTMA) within cells seemingly determine its function. PTMA undergoes 2 types of protease proteolytic modifications that are useful in elucidating its interactions with other molecules; a factor that typifies its roles. Preferably a nuclear protein, PTMA has been shown to function in the cytoplasm and extracellularly with much evidence leaning on pathognomonic status. As such, determination of its cellular distribution under normal physiological context while utilizing varied techniques is key to illuminating prospective validation of its distinct functions in different tissues. Differential distribution insights at normal physiology would also portent better basis for further clarification of its interactions and proteolytic modifications under pathological conditions like numerous cancer, ischemic stroke and immunomodulation. We therefore raised an antibody against the C terminal of PTMA to use in tandem with available antibody against the N terminal in a murine model to explicate the differences in its distribution in brain cell types and major peripheral organs through western blotting and immunohistochemical approaches. RESULTS The newly generated antibody was applied against the N-terminal antibody to distinguish truncated versions of PTMA or deduce possible masking of the protein by other interacting molecules. Western blot analysis indicated presence of a truncated form of the protein only in the thymus, while immunohistochemical analysis showed that in brain hippocampus the full-length PTMA was stained prominently in the nucleus whereas in the stomach full-length PTMA staining was not observed in the nucleus but in the cytoplasm. CONCLUSION Truncated PTMA could not be detected by western blotting when both antibodies were applied in all tissues examined except the thymus. However, immunohistochemistry revealed differential staining by these antibodies suggesting possible masking of epitopes by interacting molecules. The differential localization patterns observed in the context of nucleic versus cytoplasmic presence as well as punctate versus diffuse pattern in tissues and cell types, warrant further investigations as to the forms of PTMA interacting partners.
Collapse
Affiliation(s)
- Caroline Mwendwa Kijogi
- Department of Molecular Microbiology and Immunology, Division of Immunology, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan. .,Institute of Tropical Medicine and Infectious Diseases-KEMRI (ITROMID-KEMRI), Nairobi, Kenya.
| | - Christopher Khayeka-Wandabwa
- African Population and Health Research Center (APHRC), P. O. Box 10787-00100, Nairobi, Kenya. .,Institute of Tropical Medicine and Infectious Diseases-KEMRI (ITROMID-KEMRI), Nairobi, Kenya.
| | - Keita Sasaki
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| | - Yoshimasa Tanaka
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| | - Hiroshi Kurosu
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| | - Hayato Matsunaga
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| | - Hiroshi Ueda
- Department of Pharmacology and Therapeutic Innovation, Graduate School of Biomedical Sciences, Nagasaki University, Nagasaki, Japan.
| |
Collapse
|
10
|
Prothymosin Alpha and Immune Responses: Are We Close to Potential Clinical Applications? VITAMINS AND HORMONES 2016; 102:179-207. [PMID: 27450735 PMCID: PMC7126549 DOI: 10.1016/bs.vh.2016.04.008] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The thymus gland produces soluble molecules, which mediate significant immune functions. The first biologically active thymic extract was thymosin fraction V, the fractionation of which led to the isolation of a series of immunoactive polypeptides, including prothymosin alpha (proTα). ProTα displays a dual role, intracellularly as a survival and proliferation mediator and extracellularly as a biological response modifier. Accordingly, inside the cell, proTα is implicated in crucial intracellular circuits and may serve as a surrogate tumor biomarker, but when found outside the cell, it could be used as a therapeutic agent for treating immune system deficiencies. In fact, proTα possesses pleiotropic adjuvant activity and a series of immunomodulatory effects (eg, anticancer, antiviral, neuroprotective, cardioprotective). Moreover, several reports suggest that the variable activity of proTα might be exerted through different parts of the molecule. We first reported that the main immunoactive region of proTα is the carboxy-terminal decapeptide proTα(100-109). In conjunction with data from others, we also revealed that proTα and proTα(100-109) signal through Toll-like receptor 4. Although their precise molecular mechanism of action is yet not fully elucidated, proTα and proTα(100-109) are viewed as candidate adjuvants for cancer immunotherapy. Here, we present a historical overview on the discovery and isolation of thymosins with emphasis on proTα and data on some immune-related new activities of the polypeptide and smaller immunostimulatory peptides thereof. Finally, we propose a compiled scenario on proTα's mode of action, which could eventually contribute to its clinical application.
Collapse
|
11
|
Teixeira A, Yen B, Gusella GL, Thomas AG, Mullen MP, Aberg J, Chen X, Hoshida Y, van Bakel H, Schadt E, Basler CF, García-Sastre A, Mosoian A. Prothymosin α variants isolated from CD8+ T cells and cervicovaginal fluid suppress HIV-1 replication through type I interferon induction. J Infect Dis 2015; 211:1467-75. [PMID: 25404520 PMCID: PMC4425839 DOI: 10.1093/infdis/jiu643] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Accepted: 11/07/2014] [Indexed: 12/14/2022] Open
Abstract
Soluble factors from CD8(+) T cells and cervicovaginal mucosa of women are recognized as important in controlling human immunodeficiency virus type 1 (HIV-1) infection and transmission. Previously, we have shown the strong anti-HIV-1 activity of prothymosin α (ProTα) derived from CD8(+) T cells. ProTα is a small acidic protein with wide cell distribution, to which several functions have been ascribed, depending on its intracellular or extracellular localization. To date, activities of ProTα have been attributed to a single protein known as isoform 2. Here we report the isolation and identification of 2 new ProTα variants from CD8(+) T cells and cervicovaginal lavage with potent anti-HIV-1 activity. The first is a splice variant of the ProTα gene, known as isoform CRA_b, and the second is the product of a ProTα gene, thus far classified as a pseudogene 7. Native or recombinant ProTα variants potently restrict HIV-1 replication in macrophages through the induction of type I interferon. The baseline expression of interferon-responsive genes in primary human cervical tissues positively correlate with high levels of intracellular ProTα, and the knockdown of ProTα variants by small interfering RNA leads to downregulation of interferon target genes. Overall, these findings suggest that ProTα variants are innate immune mediators involved in immune surveillance.
Collapse
Affiliation(s)
| | | | | | | | | | | | | | | | - Harm van Bakel
- Department of Genetics and Genomics Sciences
- Icahn Institute for Genomics and Multiscale Biology
| | - Eric Schadt
- Department of Genetics and Genomics Sciences
- Icahn Institute for Genomics and Multiscale Biology
| | | | - Adolfo García-Sastre
- Department of Medicine
- Department of Microbiology
- Global Health and Emerging Pathogens Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | | |
Collapse
|
12
|
Karachaliou CE, Liolios C, Triantis C, Zikos C, Samara P, Tsitsilonis OE, Kalbacher H, Voelter W, Papadopoulos M, Pirmettis I, Livaniou E. Specific in vitro binding of a new (99m)Tc-radiolabeled derivative of the C-terminal decapeptide of prothymosin alpha on human neutrophils. Int J Pharm 2015; 486:1-12. [PMID: 25796124 DOI: 10.1016/j.ijpharm.2015.03.031] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 03/13/2015] [Accepted: 03/16/2015] [Indexed: 11/28/2022]
Abstract
Prothymosin alpha (ProTα) is a conserved mammalian polypeptide with intracellular functions associated with cell proliferation and apoptosis and an extracellular role associated with immunopotentiation. The N-terminal fragment [1-28], which is identical with the immunostimulating peptide thymosin α1 (Tα1), was earlier considered as the immunoactive region of the polypeptide; however, recent data suggest that ProTα may exert a discrete immunomodulating action through its central or C-terminal region, via targeting Toll-like receptor- 4 (TLR4). In this work, a derivative of the C-terminal fragment ProTα[100-109] (ProTα-D1) that can be radiolabeled with (99m)Tc was developed. The biological activity of the non-radioactive (185/187)rhenium-complex of this derivative ([(185/187)Re]ProTα-D1, structurally similar with [(99m)Tc]ProTα-D1) was verified through suitable in vitro bioassays on human neutrophils. Subsequent cell-binding studies revealed specific, time-dependent and saturable binding of [(99m)Tc]ProTα-D1 on neutrophils, which was inhibited by intact ProTα and ProTα[100-109], as well as by a "prototype" TLR4-ligand (lipopolysaccharide from Escherichia coli). Overall, our results support the existence of ProTα-binding sites on human neutrophils, recognizing [(99m)Tc]ProTα-D1, which might involve TLR4. [(99m)Tc]ProTα-D1 may be a useful tool for conducting further in vitro and in vivo studies, aiming to elucidate the extracellular mode of action of ProTα and, eventually, develop ProTα-based immunotherapeutics.
Collapse
Affiliation(s)
- Chrysoula-Evangelia Karachaliou
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Christos Liolios
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Charalampos Triantis
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Christos Zikos
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Pinelopi Samara
- Faculty of Biology, University of Athens, Athens 15784, Greece
| | | | - Hubert Kalbacher
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - Wolfgang Voelter
- Interfaculty Institute of Biochemistry, University of Tuebingen, Tuebingen 72076, Germany
| | - Minas Papadopoulos
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Ioannis Pirmettis
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece
| | - Evangelia Livaniou
- Institute of Nuclear and Radiological Sciences & Technology, Energy and Safety (INRaSTES), National Center for Scientific Research "Demokritos", Athens 15310, Greece.
| |
Collapse
|
13
|
Su BH, Tseng YL, Shieh GS, Chen YC, Shiang YC, Wu P, Li KJ, Yen TH, Shiau AL, Wu CL. Prothymosin α overexpression contributes to the development of pulmonary emphysema. Nat Commun 2013; 4:1906. [PMID: 23695700 PMCID: PMC3674284 DOI: 10.1038/ncomms2906] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2013] [Accepted: 04/22/2013] [Indexed: 01/11/2023] Open
Abstract
Emphysema is one of the disease conditions that comprise chronic obstructive pulmonary disease. Prothymosin α transgenic mice exhibit an emphysema phenotype, but the pathophysiological role of prothymosin α in emphysema remains unclear. Here we show that prothymosin α contributes to the pathogenesis of emphysema by increasing acetylation of histones and nuclear factor-kappaB, particularly upon cigarette smoke exposure. We find a positive correlation between prothymosin α levels and the severity of emphysema in prothymosin α transgenic mice and emphysema patients. Prothymosin α overexpression increases susceptibility to cigarette smoke-induced emphysema, and cigarette smoke exposure further enhances prothymosin α expression. We show that prothymosin α inhibits the association of histone deacetylases with histones and nuclear factor-kappaB, and that prothymosin α overexpression increases expression of nuclear factor-kappaB-dependent matrix metalloproteinase 2 and matrix metalloproteinase 9, which are found in the lungs of patients with chronic obstructive pulmonary disease. These results demonstrate the clinical relevance of prothymosin α in regulating acetylation events during the pathogenesis of emphysema. Pulmonary emphysema obstruct airflow in the lung and often develop in smokers. Here Su et al. show that prothymosin α contributes to emphysema development through alterations in the acetylation of histones and the transcription factor NF-κB, and that exposure to cigarette smoke increases prothymosin α expression.
Collapse
Affiliation(s)
- Bing-Hua Su
- Department of Biochemistry and Molecular Biology, National Cheng Kung University Medical College, Tainan 70101, Taiwan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
14
|
Baxevanis CN, Voutsas IF, Tsitsilonis OE. Toll-like receptor agonists: current status and future perspective on their utility as adjuvants in improving anticancer vaccination strategies. Immunotherapy 2013; 5:497-511. [PMID: 23638745 DOI: 10.2217/imt.13.24] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Toll-like receptor (TLR) agonists possess remarkable properties, particularly with regard to dendritic cell activation, promoting Th1-type cytokine production and optimizing cytotoxic T-cell responses. Preclinical and clinical studies conducted to date show that TLR agonists can improve currently applied anticancer vaccination protocols. Although these have resulted in the US FDA approval of three TLR agonists for use in humans, their abundant application encounters limitations, principally due to dose-limiting toxicity evoking from systemic cytokine production. Here, using selected examples of clinical studies, we provide a concise review regarding the knowledge acquired thus far on the adjuvant use of TLR agonists as cancer vaccine components. We also provide evidence on the exploitation of a novel TLR agonist, prothymosin-α, which enhances the efficacy of tumor-reactive effectors without causing severe adverse effects.
Collapse
|
15
|
Hiong KC, Ip YK, Wong WP, Chew SF. Differential gene expression in the brain of the African lungfish, Protopterus annectens, after six days or six months of aestivation in air. PLoS One 2013; 8:e71205. [PMID: 23976998 PMCID: PMC3745453 DOI: 10.1371/journal.pone.0071205] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2013] [Accepted: 07/03/2013] [Indexed: 11/18/2022] Open
Abstract
The African lungfish, Protopterus annectens, can undergo aestivation during drought. Aestivation has three phases: induction, maintenance and arousal. The objective of this study was to examine the differential gene expression in the brain of P. annectens during the induction (6 days) and maintenance (6 months) phases of aestivation as compared with the freshwater control using suppression subtractive hybridization. During the induction phase of aestivation, the mRNA expression of prolactin (prl) and growth hormone were up-regulated in the brain of P. annectens, which indicate for the first time the possible induction role of these two hormones in aestivation. Also, the up-regulation of mRNA expression of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein γ polypeptide and the down-regulation of phosphatidylethanolamine binding protein, suggest that there could be a reduction in biological and neuronal activities in the brain. The mRNA expression of cold inducible RNA-binding protein and glucose regulated protein 58 were also up-regulated in the brain, probably to enhance their cytoprotective effects. Furthermore, the down-regulation of prothymosin α expression suggests that there could be a suppression of transcription and cell proliferation in preparation for the maintenance phase. In general, the induction phase appeared to be characterized by reduction in glycolytic capacity and metabolic activity, suppression of protein synthesis and degradation, and an increase in defense against ammonia toxicity. In contrast, there was a down-regulation in the mRNA expression of prl in the brain of P. annectens during the maintenance phase of aestivation. In addition, there could be an increase in oxidative defense capacity, and up-regulation of transcription, translation, and glycolytic capacities in preparation for arousal. Overall, our results signify the importance of reconstruction of protein structures and regulation of energy expenditure during the induction phase, and the needs to suppress protein degradation and conserve metabolic fuel stores during the maintenance phase of aestivation.
Collapse
Affiliation(s)
- Kum C. Hiong
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, Singapore, Republic of Singapore
| | - Yuen K. Ip
- Department of Biological Sciences, National University of Singapore, Singapore, Republic of Singapore
| | - Wai P. Wong
- Department of Biological Sciences, National University of Singapore, Singapore, Republic of Singapore
| | - Shit F. Chew
- Natural Sciences and Science Education, National Institute of Education, Nanyang Technological University, Singapore, Republic of Singapore
| |
Collapse
|
16
|
Emmanouilidou A, Karetsou Z, Tzima E, Kobayashi T, Papamarcaki T. Knockdown of prothymosin α leads to apoptosis and developmental defects in zebrafish embryos. Biochem Cell Biol 2013; 91:325-32. [PMID: 24032683 DOI: 10.1139/bcb-2012-0103] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Prothymosin alpha (ProTα) is an abundant nuclear protein involved in cellular processes intricately linked to development, such as cell proliferation and apoptosis. Although it is known that ProTα inhibits the formation of apoptosome and blocks caspase-3 activity, its mechanism of function in the apoptotic machinery is still under investigation. We have studied the cellular role of ProTα by knocking down its expression in HeLa cells with small hairpin RNA (shRNA) in the absence of apoptotic stimuli. Flow cytometric analysis showed that the live cell population was significantly decreased with a concomitant increase of the apoptotic populations. To understand the physiological role of ProTα within the context of embryonic development, we knocked down the Ptmab zebrafish ortholog using 2 specific morpholino oligonucleotides. Ptmab morphants exhibited growth retardation, bended trunks, and curly tails. The frequency of occurrence of the phenotypic defects was increased in a morpholino dose-dependent manner. Co-injection of ptmaa mRNA with ptmab morpholino partially rescued the morphological defects. Immunostaining with the anti-phospho-histone H3 (pH3) antibody suggested that the abnormalities of Ptmab morphants could be due to defective cell proliferation that results in growth imbalances. TUNEL fluorescent labelling and Acridine Orange staining of the morphants showed high rates of cell death in the head and tail regions. Concomitantly, the active form of caspase-3 was detected in Ptmab morphants. Our data suggest a conserved anti-apoptotic role of ProTα between zebrafish and humans, and provide the first evidence that ProTα is important for early embryogenesis.
Collapse
Affiliation(s)
- Anastasia Emmanouilidou
- a Laboratory of Biological Chemistry, Medical School, University of Ioannina, 451 10 Ioannina, Greece
| | | | | | | | | |
Collapse
|
17
|
Development of an ELISA for the quantification of the C-terminal decapeptide prothymosin α(100-109) in sera of mice infected with bacteria. J Immunol Methods 2013; 395:54-62. [PMID: 23831611 DOI: 10.1016/j.jim.2013.06.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/21/2013] [Accepted: 06/21/2013] [Indexed: 11/20/2022]
Abstract
Apoptosis is characterized by a series of discrete biochemical events, among which is the truncation of the nuclear polypeptide prothymosin alpha (proTα) by activated caspase-3. This early apoptotic event results in the generation of a carboxy-terminal fragment of proTα, the immunoactive decapeptide proTα(100-109). We hypothesized that the detection of increased levels of proTα(100-109) in serum can be directly correlated with the induction of massive cell apoptosis, resulting from a severe bacterial infection. Thus, using high-affinity-purified polyclonal antibodies (Abs), raised in rabbits and a prototype antibody-capture system, we developed a highly sensitive and specific competitive ELISA for proTα(100-109). The sensitivity of the ELISA (0.1ng/mL to 10μg/mL) is acceptable for the quantification of the decapeptide in serum samples. To assess our initial hypothesis, we determined the concentration of proTα(100-109) in the sera of mice infected with the bacterium Streptococcus pyogenes over the course of the infection. We show that serum concentration of proTα(100-109) was marginal to undetectable before infection, increased over time and peaked at 72h postinfection. In silico analysis suggests that the Abs generated are unlikely to cross-react with any other unrelated mouse or bacterial protein. Further validation of our ELISA using serum samples from humans, infected with bacteria, may provide a useful tool to differentiate the causative agent of a potentially lethal septic infection.
Collapse
|
18
|
Abstract
Inside cells, the concentration of macromolecules can reach up to 400 g/L. In such crowded environments, proteins are expected to behave differently than in vitro. It has been shown that the stability and the folding rate of a globular protein can be altered by the excluded volume effect produced by a high density of macromolecules. However, macromolecular crowding effects on intrinsically disordered proteins (IDPs) are less explored. These proteins can be extremely dynamic and potentially sample a wide ensemble of conformations under non-denaturing conditions. The dynamic properties of IDPs are intimately related to the timescale of conformational exchange within the ensemble, which govern target recognition and how these proteins function. In this work, we investigated the macromolecular crowding effects on the dynamics of several IDPs by measuring the NMR spin relaxation parameters of three disordered proteins (ProTα, TC1, and α-synuclein) with different extents of residual structures. To aid the interpretation of experimental results, we also performed an MD simulation of ProTα. Based on the MD analysis, a simple model to correlate the observed changes in relaxation rates to the alteration in protein motions under crowding conditions was proposed. Our results show that 1) IDPs remain at least partially disordered despite the presence of high concentration of other macromolecules, 2) the crowded environment has differential effects on the conformational propensity of distinct regions of an IDP, which may lead to selective stabilization of certain target-binding motifs, and 3) the segmental motions of IDPs on the nanosecond timescale are retained under crowded conditions. These findings strongly suggest that IDPs function as dynamic structural ensembles in cellular environments.
Collapse
|
19
|
Ueda H, Matsunaga H, Halder SK. Prothymosin α plays multifunctional cell robustness roles in genomic, epigenetic, and nongenomic mechanisms. Ann N Y Acad Sci 2012; 1269:34-43. [DOI: 10.1111/j.1749-6632.2012.06675.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
20
|
Ioannou K, Samara P, Livaniou E, Derhovanessian E, Tsitsilonis OE. Prothymosin alpha: a ubiquitous polypeptide with potential use in cancer diagnosis and therapy. Cancer Immunol Immunother 2012; 61:599-614. [PMID: 22366887 PMCID: PMC11029552 DOI: 10.1007/s00262-012-1222-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2011] [Accepted: 02/10/2012] [Indexed: 01/06/2023]
Abstract
The thymus is a central lymphoid organ with crucial role in generating T cells and maintaining homeostasis of the immune system. More than 30 peptides, initially referred to as "thymic hormones," are produced by this gland. Although the majority of them have not been proven to be thymus-specific, thymic peptides comprise an effective group of regulators, mediating important immune functions. Thymosin fraction five (TFV) was the first thymic extract shown to stimulate lymphocyte proliferation and differentiation. Subsequent fractionation of TFV led to the isolation and characterization of a series of immunoactive peptides/polypeptides, members of the thymosin family. Extensive research on prothymosin α (proTα) and thymosin α1 (Tα1) showed that they are of clinical significance and potential medical use. They may serve as molecular markers for cancer prognosis and/or as therapeutic agents for treating immunodeficiencies, autoimmune diseases and malignancies. Although the molecular mechanisms underlying their effect are yet not fully elucidated, proTα and Tα1 could be considered as candidates for cancer immunotherapy. In this review, we will focus in principle on the eventual clinical utility of proTα, both as a tumor biomarker and in triggering anticancer immune responses. Considering the experience acquired via the use of Tα1 to treat cancer patients, we will also discuss potential approaches for the future introduction of proTα into the clinical setting.
Collapse
Affiliation(s)
- Kyriaki Ioannou
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784 Athens, Greece
| | - Pinelopi Samara
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784 Athens, Greece
| | - Evangelia Livaniou
- Immunopeptide Chemistry Lab, Institute of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research “Demokritos”, Patriarchou Gregoriou and Neapoleos, Aghia Paraskevi, 15310 Athens, Greece
| | - Evelyna Derhovanessian
- Tübingen Ageing and Tumour Immunology Group, Center for Medical Research, University of Tübingen Medical School, Waldhörnlestr. 22, 72072 Tübingen, Germany
| | - Ourania E. Tsitsilonis
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784 Athens, Greece
| |
Collapse
|
21
|
Intracellular and extracellular cytokine-like functions of prothymosin α: implications for the development of immunotherapies. Future Med Chem 2012; 3:1199-208. [PMID: 21806381 DOI: 10.4155/fmc.11.72] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Prothymosin α (ProTα) is a 12.5-kDa, highly acidic protein widely distributed in different cell types expressed intracellularly and extracellularly. ProTα does not contain a secretion-signal sequence and is released by a nonclassical secretory pathway with a cargo protein. New findings on the extracellular function of ProTα have yielded exciting insights into the cytokine-like functions of this host protein that stimulates type I interferon via Toll-like receptor 4. Here, we discuss the intracellular function of ProTα, how new findings of cytokine-like activities of ProTα aid our understanding of mechanisms that direct ProTα functions, and the potential application of these new insights to the development of immunotherapies.
Collapse
|
22
|
Zakharova NI, Sokolov VV, Suvorova AA, Shiau AL, Wu CL, Evstafieva AG. Prothymosin alpha interacts with C-terminal domain of histone H1 and dissociates p53-histone H1 complex. Mol Biol 2011. [DOI: 10.1134/s0026893311040157] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
23
|
Stress-induced non-vesicular release of prothymosin-α initiated by an interaction with S100A13, and its blockade by caspase-3 cleavage. Cell Death Differ 2010; 17:1760-72. [PMID: 20467443 DOI: 10.1038/cdd.2010.52] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The nuclear protein prothymosin-α (ProTα), which lacks a signal peptide sequence, is released from neurons and astrocytes on ischemic stress and exerts a unique form of neuroprotection through an anti-necrotic mechanism. Ischemic stress-induced ProTα release is initiated by a nuclear release, followed by extracellular release in a non-vesicular manner, in C6 glioma cells. These processes are caused by ATP loss and elevated Ca²(+), respectively. S100A13, a Ca²(+)-binding protein, was identified to be a major protein co-released with ProTα in an immunoprecipitation assay. The Ca²(+)-dependent interaction between ProTα and S100A13 was found to require the C-terminal peptide sequences of both proteins. In C6 glioma cells expressing a Δ88-98 mutant of S100A13, serum deprivation caused the release of S100A13 mutant, but not of ProTα. When cells were administered apoptogenic compounds, ProTα was cleaved by caspase-3 to generate a C-terminal peptide-deficient fragment, which lacks the nuclear localization signal (NLS). However, there was no extracellular release of ProTα. All these results suggest that necrosis-inducing stress induces an extacellular release of ProTα in a non-vesicular manner, whereas apoptosis-inducing stress does not, owing to the loss of its interaction with S100A13, a cargo molecule for extracellular release.
Collapse
|
24
|
Jou YC, Tung CL, Tsai YS, Shen CH, Syue-Yi C, Shiau AL, Tsai HT, Wu CL, Tzai TS. Prognostic Relevance of Prothymosin-α Expression in Human Upper Urinary Tract Transitional Cell Carcinoma. Urology 2009; 74:951-7. [DOI: 10.1016/j.urology.2008.11.060] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2008] [Revised: 10/31/2008] [Accepted: 11/22/2008] [Indexed: 10/20/2022]
|
25
|
Skopeliti M, Iconomidou VA, Derhovanessian E, Pawelec G, Voelter W, Kalbacher H, Hamodrakas SJ, Tsitsilonis OE. Prothymosin α immunoactive carboxyl-terminal peptide TKKQKTDEDD stimulates lymphocyte reactions, induces dendritic cell maturation and adopts a β-sheet conformation in a sequence-specific manner. Mol Immunol 2009; 46:784-92. [DOI: 10.1016/j.molimm.2008.09.014] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 09/02/2008] [Accepted: 09/03/2008] [Indexed: 10/21/2022]
|
26
|
Klimentzou P, Drougou A, Fehrenbacher B, Schaller M, Voelter W, Barbatis C, Paravatou-Petsotas M, Livaniou E. Immunocytological and preliminary immunohistochemical studies of prothymosin alpha, a human cancer-associated polypeptide, with a well-characterized polyclonal antibody. J Histochem Cytochem 2008; 56:1023-31. [PMID: 18711212 DOI: 10.1369/jhc.2008.950956] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Prothymosin alpha (ProTalpha) is a nuclear polypeptide of great biological and, possibly clinical, importance, because its expression levels have been associated with early diagnosis/prognosis of human cancer. It is therefore interesting to raise easily available and cost-effective antibodies that would be applied to develop reliable ProTalpha immunodiagnostics. In this study, New Zealand white rabbits and laying hens were parallel immunized against intact ProTalpha or the synthetic fragments ProTalpha[1-28], ProTalpha[87-109], and ProTalpha[101-109], all conjugated to keyhole limpet hemocyanin (KLH). The corresponding antibodies G and Y were immunochemically evaluated in parallel with ELISA and Western blot systems and applied to fluorescence immunocytology experiments using various cancer cell lines and normal cells. The antibody G raised against ProTalpha[101-109]/KLH had excellent functional characteristics in the Western blot and immunocytology experiments, where the fluorescent signal was almost exclusively shown in the cell nucleus independently of the cells assayed. The above antibody has been applied to preliminary IHC staining of human cancer prostate tissues, leading to a high percentage of clearly and intensively stained nuclei in the adenocarcinoma tissue; this antibody can be further used in cancer tissue immunostaining and in research concerning the role of ProTalpha in tumorigenesis.
Collapse
Affiliation(s)
- Persefoni Klimentzou
- Institute of Radioisotopes and Radiodiagnostic Products, National Centre for Scientific Research "Demokritos," Aghia Paraskevi, Athens, Greece
| | | | | | | | | | | | | | | |
Collapse
|
27
|
Zakharova NI, Sokolov VV, Roudko VV, Melnikov SV, Vartapetian AB, Evstafieva AG. Effect of prothymosin α and its mutants on the activity of the p53 tumor suppressor. Mol Biol 2008. [DOI: 10.1134/s002689330804016x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
28
|
Tsai YS, Jou YC, Lee GF, Chen YC, Shiau AL, Tsai HT, Wu CL, Tzai TS. Aberrant prothymosin-alpha expression in human bladder cancer. Urology 2008; 73:188-92. [PMID: 18692879 DOI: 10.1016/j.urology.2008.05.031] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2008] [Revised: 04/04/2008] [Accepted: 05/21/2008] [Indexed: 02/01/2023]
Abstract
OBJECTIVES To investigate the prothymosin-alpha (PTMA) expression in human bladder cancer using tissue microarrays. METHODS Two tissue microarray slides of 50 bladder tumors and 42 paired normal adjacent tissues were investigated using immunohistochemical staining. The staining distribution was categorized as negative, nuclear, cytoplasmic, and mixed expression. Quantitative immunoreactivity was measured using image analysis, as represented by the integrated optical density for each tissue core. RESULTS In 36 of 42 normal adjacent tissues, positive PTMA immunoreactivity could be seen in some nuclei of the normal urothelial cells, but not, or only minimally, in the cytoplasm and underlying submucosal tissues. A statistically significant enhancement of PTMA expression was found in bladder tumors of each grade compared with the normal adjacent tissue (P < .0001 for normal adjacent tissues vs grade 1, 2, or 3 tumors, paired t test). Of 48 transitional cell carcinoma specimens, only 4 (8.3%) were graded as negative and 44 (91.7%) were positive for PTMA expression, including nuclear (n = 8), cytoplasmic (n = 12), and mixed expression (n = 24) patterns. A statistically significant correlation was found between high grade and mixed expression (P = 0.0020, chi(2) test). CONCLUSIONS Increased PTMA expression was found in human bladder cancers compared with the paired normal adjacent bladder tissue. The distribution of PTMA expression was changed in high-grade tumors. The clinical significance of such an aberrant PTMA expression in bladder cancer is worthy of additional investigation.
Collapse
Affiliation(s)
- Yuh-Shyan Tsai
- Institute of Clinical Medicine, University Hospital and Douliou Branch, National Cheng Kung University College of Medicine, Tainan, Taiwan
| | | | | | | | | | | | | | | |
Collapse
|
29
|
Padmanabhan B, Nakamura Y, Yokoyama S. Structural analysis of the complex of Keap1 with a prothymosin alpha peptide. Acta Crystallogr Sect F Struct Biol Cryst Commun 2008; 64:233-8. [PMID: 18391415 PMCID: PMC2374262 DOI: 10.1107/s1744309108004995] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2008] [Accepted: 02/21/2008] [Indexed: 12/18/2022]
Abstract
The Nrf2 transcription factor, which plays important roles in oxidative and xenobiotic stress, is negatively regulated by the cytoplasmic repressor Keap1. The beta-propeller/Kelch domain of Keap1, which is formed by the double-glycine repeat and C-terminal region domains (Keap1-DC), interacts directly with the Neh2 domain of Nrf2. The nuclear oncoprotein prothymosin alpha (ProTalpha) also interacts directly with Keap1 and may play a role in the dissociation of the Keap1-Nrf2 complex. The structure of Keap1-DC complexed with a ProTalpha peptide (amino acids 39-54) has been determined at 1.9 A resolution. The Keap1-bound ProTalpha peptide possesses a hairpin conformation and binds to the Keap1 protein at the bottom region of the beta-propeller domain. Complex formation occurs as a consequence of their complementary electrostatic interactions. A comparison of the present structure with recently reported Keap1-DC complex structures revealed that the DLG and ETGE motifs of the Neh2 domain of Nrf2 and the ProTalpha peptide bind to Keap1 in a similar manner but with different binding potencies.
Collapse
Affiliation(s)
- Balasundaram Padmanabhan
- Genomic Sciences Center, Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
| | - Yoshihiro Nakamura
- Genomic Sciences Center, Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
| | - Shigeyuki Yokoyama
- Genomic Sciences Center, Yokohama Institute, RIKEN, 1-7-22 Suehiro-cho, Tsurumi, Yokohama 230-0045, Japan
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| |
Collapse
|
30
|
Melnikov SV, Evstafieva AG, Vartapetian AB. Interaction with Keap1 does not lead to ubiquitination and degradation of prothymosin α. Mol Biol 2007. [DOI: 10.1134/s0026893307050123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
31
|
Arnoys EJ, Wang JL. Dual localization: proteins in extracellular and intracellular compartments. Acta Histochem 2007; 109:89-110. [PMID: 17257660 DOI: 10.1016/j.acthis.2006.10.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2006] [Revised: 10/01/2006] [Accepted: 10/09/2006] [Indexed: 12/24/2022]
Abstract
The goal of this article is to provide a comprehensive catalog of those proteins documented to exhibit dual localization, being found in both the extracellular compartment (cell surface and extracellular medium) as well as the intracellular compartment (cytosol and nucleus). A large subset of these proteins that show dual localization is found both in the nucleus and outside of cells. Proteins destined to be secreted out of the cell or to be expressed at the cell surface usually enter the endomembrane pathway on the basis of a signal sequence that targets them into the endoplasmic reticulum. Proteins destined for import into the nucleus, on the other hand, usually carry a nuclear localization signal. We have organized our catalog in terms of the presence and absence of these trafficking signals: (a) proteins that contain a signal sequence but no nuclear localization signal; (b) proteins that contain both a signal sequence as well as a nuclear localization signal; (c) proteins that contain a nuclear localization signal but lack a signal sequence; and (d) proteins containing neither a signal sequence nor a nuclear localization signal. Novel insights regarding the activities of several classes of proteins exhibiting dual localization can be derived when one targeting signal is experimentally abrogated. For example, the mitogenic activity of both fibroblasts growth factor-1 and schwannoma-derived growth factor clearly requires nuclear localization, independent of the activation of the receptor tyrosine kinase signaling pathway. In addition, there is a growing list of integral membrane receptors that undergo translocation to the nucleus, with bona fide nuclear localization signals and transcription activation activity. The information provided in this descriptive catalog will, hopefully, stimulate investigations into the pathways and mechanisms of transport between these compartments and the physiological significance of dual localization.
Collapse
Affiliation(s)
- Eric J Arnoys
- Department of Chemistry and Biochemistry, Calvin College, Grand Rapids, MI 49546, USA
| | | |
Collapse
|
32
|
Chen YC, Chang MY, Shiau AL, Yo YT, Wu CL. Mitochondrial ribosomal protein S36 delays cell cycle progression in association with p53 modification and p21WAF1/CIP1 expression. J Cell Biochem 2007; 100:981-90. [PMID: 17131359 DOI: 10.1002/jcb.21079] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Ribosomal biogenesis is correlated with cell cycle, cell proliferation, cell growth and tumorigenesis. Some oncogenes and tumor suppressors are involved in regulating the formation of mature ribosome and affecting the ribosomal biogenesis. In previous studies, the mitochondrial ribosomal protein L41 was reported to be involved in cell proliferation regulating through p21(WAF1/CIP1) and p53 pathway. In this report, we have identified a mitochondrial ribosomal protein S36 (mMRPS36), which is localized in the mitochondria, and demonstrated that overexpression of mMRPS36 in cells retards the cell proliferation and delays cell cycle progression. In addition, the mMRPS36 overexpression induces p21(WAF1/CIP1) expression, and regulates the expression and phosphorylation of p53. Our result also indicate that overexpression of mMRPS36 affects the mitochondrial function. These results suggest that mMRPS36 plays an important role in mitochondrial ribosomal biogenesis, which may cause nucleolar stress, thereby leading to cell cycle delay.
Collapse
Affiliation(s)
- Yeong-Chang Chen
- Institute of Basic Medical Sciences, National Cheng Kung University Medical College, Tainan, Taiwan
| | | | | | | | | |
Collapse
|
33
|
Covelo G, Sarandeses CS, Díaz-Jullien C, Freire M. Prothymosin α Interacts with Free Core Histones in the Nucleus of Dividing Cells. ACTA ACUST UNITED AC 2006; 140:627-37. [PMID: 17012289 DOI: 10.1093/jb/mvj197] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The acidic protein prothymosin alpha (ProTalpha), with a broad presence in mammalian cells, has been widely considered to have a role in cell division, through an unrevealed mechanism in which histones may be involved in view of their ability to interact with ProTalpha in vitro. Results of co-immunoprecipitation experiments presented here demonstrate that ProTalpha interacts in vivo with core histones in proliferating B-lymphocytes (NC-37 cells). This interaction occurs with histones H3, H2A, H2B and H4 located free in the nucleoplasm, whereas no interaction was detected with histone H1, mono-nucleosome particles or chromatin. Moreover, the core histones form part of a nuclear multiprotein complex of about 700 kDa separated by ProTalpha-Sepharose affinity, with components including H3 and H4 acetyltranferases, H3 methyltransferases, hnRNP isotypes A3, A2/B1 and R, ATP-dependent and independent DNA helicases II, beta-actin and vimentin, all co-purifying by gel filtration. This indicates that the interaction of ProTalpha with core histones in the nucleus may be related to the structural modification of histones H3 and H4, and hence to chromatin activity, raising the possibility that the other proteins in the nuclear complex may play a role in this process.
Collapse
Affiliation(s)
- Guillermo Covelo
- Departamento de Bioquímica y Biología Molecular, Facultad de Biología, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | | | | | | |
Collapse
|
34
|
Skopeliti M, Voutsas IF, Klimentzou P, Tsiatas ML, Beck A, Bamias A, Moraki M, Livaniou E, Neagu M, Voelter W, Tsitsilonis OE. The immunologically active site of prothymosin alpha is located at the carboxy-terminus of the polypeptide. Evaluation of its in vitro effects in cancer patients. Cancer Immunol Immunother 2006; 55:1247-57. [PMID: 16453152 PMCID: PMC11030181 DOI: 10.1007/s00262-005-0108-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2005] [Accepted: 11/16/2005] [Indexed: 10/25/2022]
Abstract
Prothymosin alpha (proTalpha) is a 109 amino acid long polypeptide presenting distinct immunoenhancing activity in vitro and in vivo. Recent reports suggest that in apoptotic cells, proTalpha is cleaved by caspases at its carboxy(C)-terminus generating potentially bioactive fragments. In this study, we identified the peptide segment of proTalpha presenting maximum immunomodulatory activity. Calf thymus proTalpha was trypsinised, and the five fragments produced (spanning residues 1-14, 21-30, 31-87, 89-102 and 103-109) were tested for their ability to stimulate healthy donor- and cancer patient-derived peripheral blood mononuclear cell (PBMC) proliferation in autologous mixed lymphocyte reaction (AMLR), natural killer and lymphokine-activated killer cell activity, intracellular production of perforin, upregulation of adhesion molecules and CD25 expression. ProTalpha(89-102) and proTalpha(103-109) significantly fortified healthy donor-lymphocytes' immune responses to levels comparable to those induced by intact proTalpha. These effects were more pronounced in cancer patients, where peptides proTalpha(89-102) and proTalpha(103-109) partly, however significantly, restored the depressed AMLR and cytolytic ability of PBMC, by simulating the biological activity exerted by intact proTalpha. ProTalpha(1-14), proTalpha(21-30) and proTalpha(31-87) marginally upregulated lymphocyte activation. This is the first report showing that proTalpha's immunomodulating activity can be substituted by its C-terminal peptide(s). Whether generation and externalization of such immunoactive proTalpha fragments occurs in vivo, needs further investigation. However, if these peptides can trigger immune responses, they may eventually be used therapeutically to improve some PBMC functions of cancer patients.
Collapse
Affiliation(s)
- Margarita Skopeliti
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784, Ilissia, Athens, Greece
| | - Ioannis F. Voutsas
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784, Ilissia, Athens, Greece
| | | | - Marinos L. Tsiatas
- Department of Clinical Therapeutics, “Alexandra” Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Alexander Beck
- Central Laboratory, Department of Internal Medicine IV, University Clinic of Tuebingen, Tuebingen, Germany
| | - Aristotelis Bamias
- Department of Clinical Therapeutics, “Alexandra” Hospital, School of Medicine, University of Athens, Athens, Greece
| | - Maria Moraki
- Blood Transfusion Unit, “St. Savas” Cancer Hospital, Athens, Greece
| | | | - Monica Neagu
- Immunology Laboratory, Victor Babes National Research Institute, Bucharest, Romania
| | - Wolfgang Voelter
- Biochemistry Institute, University of Tuebingen, Tuebingen, Germany
| | - Ourania E. Tsitsilonis
- Department of Animal and Human Physiology, Faculty of Biology, University of Athens, Panepistimiopolis, 15784, Ilissia, Athens, Greece
| |
Collapse
|
35
|
Barbini L, Gonzalez R, Dominguez F, Vega F. Apoptotic and proliferating hepatocytes differ in prothymosin α expression and cell localization. Mol Cell Biochem 2006; 291:83-91. [PMID: 16845491 DOI: 10.1007/s11010-006-9200-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2006] [Accepted: 03/22/2006] [Indexed: 11/28/2022]
Abstract
Prothymosin alpha is an acidic protein, reported to be involved in cell proliferation and apoptosis, although its precise function in both processes are still unknown. Due to the importance of these processes in the pathogenesis of hepatic diseases and the need to understand the molecular mechanisms underlying these diseases we aimed to investigate the behavior of this protein in liver growth and apoptosis, in two models of hepatocytes in culture. Prothymosin alpha expression varied throughout the hepatocyte cell cycle, according to its progression. Proliferating hepatocytes showed increased expression of the protein, while apoptotic ones showed decreased levels. The subcellular location of prothymosin alpha differed according to the different phases of the cell cycle. Thus, it appeared with a stippled and widely dispersed pattern throughout the nucleus in quiescent and proliferating hepatocytes, while it became cytoplasmic in mitotic and late apoptotic cells. These results are in agreement with the idea that high levels of prothymosin alpha need to be present in the nucleus for proliferation, and programmed cell death requires low levels of prothymosin alpha outside of the nucleus. The differences in prothymosin alpha expression and localization during hepatocyte proliferation and apoptosis suggest that this protein may have a pleiotropic function that depends not only on its availability but also on its various localizations in different subcellular compartments.
Collapse
Affiliation(s)
- Luciana Barbini
- Departamento de Fisiologia, Facultad de Veterinaria, Universidad de Santiago de Compostela, Lugo, España
| | | | | | | |
Collapse
|
36
|
Kobayashi T, Wang T, Maezawa M, Kobayashi M, Ohnishi S, Hatanaka K, Hige S, Shimizu Y, Kato M, Asaka M, Tanaka J, Imamura M, Hasegawa K, Tanaka Y, Brachmann RK. Overexpression of the oncoprotein prothymosin alpha triggers a p53 response that involves p53 acetylation. Cancer Res 2006; 66:3137-44. [PMID: 16540664 DOI: 10.1158/0008-5472.can-05-2112] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Activation of the tumor suppressor protein p53 is a critical cellular response to various stress stimuli and to inappropriate activity of growth-promoting proteins, such as Myc, Ras, E2F, and beta-catenin. Protein stability and transcriptional activity of p53 are modulated by protein-protein interactions and post-translational modifications, including acetylation. Here, we show that inappropriate activity of prothymosin alpha (PTMA), an oncoprotein overexpressed in human cancers, triggers a p53 response. Overexpression of PTMA enhanced p53 transcriptional activity in reporter gene assays for p53 target gene promoters hdm2, p21, and cyclin G. Overexpressed PTMA resulted in increased mRNA and protein levels for endogenous p53 target genes, hdm2 and p21, and in growth suppression. In contrast, reduction of endogenous PTMA through RNA interference decreased p53 transcriptional activity. Histone acetyltransferases (HATs) act as p53 coactivators and acetylate p53. PTMA, known to interact with HATs, led to increased levels of acetylated p53. PTMA did not increase the transcriptional activity of an acetylation-deficient p53 mutant, suggesting that p53 acetylation is an indispensable part of the p53 response to PTMA. Chromatin immunoprecipitation assays showed that excess PTMA associates with the p21 promoter and results in increased levels of acetylated p53 at the p21 promoter. Our findings indicate that overexpressed PTMA elicits a p53 response that involves p53 acetylation.
Collapse
Affiliation(s)
- Takahiko Kobayashi
- Hokkaido University Medical Hospital, Primary Care Medicine, Sapporo, Japan.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
37
|
New Functions of a Well-Known Protein: Prothymosin α Is Involved in Protecting Cells from Apoptosis and Oxidative Stress. Mol Biol 2005. [DOI: 10.1007/s11008-005-0079-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
38
|
Lal A, Kawai T, Yang X, Mazan-Mamczarz K, Gorospe M. Antiapoptotic function of RNA-binding protein HuR effected through prothymosin alpha. EMBO J 2005; 24:1852-62. [PMID: 15861128 PMCID: PMC1142594 DOI: 10.1038/sj.emboj.7600661] [Citation(s) in RCA: 143] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Accepted: 04/05/2005] [Indexed: 11/08/2022] Open
Abstract
We report the antiapoptotic effect of RNA-binding protein HuR, a critical regulator of the post-transcriptional fate of target transcripts. Among the most prominent mRNAs complexing with HuR is that encoding prothymosin alpha (ProTalpha), an inhibitor of the apoptosome. In HeLa cells, treatment with the apoptotic stimulus ultraviolet light (UVC) triggered the mobilization of ProTalpha mRNA to the cytoplasm and onto heavier polysomes, where its association with HuR increased dramatically. Analysis of a chimeric ProTalpha mRNA directly implicated HuR in regulating ProTalpha production: ProTalpha translation and cytoplasmic concentration increased in HuR-overexpressing cells and declined in cells in which HuR levels were lowered by RNA interference. Importantly, the antiapoptotic influence engendered by HuR was vitally dependent on ProTalpha expression, since use of oligomers that blocked ProTalpha translation abrogated the protective effect of HuR. Together, our data support a regulatory scheme whereby HuR binds the ProTalpha mRNA, elevates its cytoplasmic abundance and translation, and thereby elicits an antiapoptotic program.
Collapse
Affiliation(s)
- Ashish Lal
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Tomoko Kawai
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Xiaoling Yang
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Krystyna Mazan-Mamczarz
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
| | - Myriam Gorospe
- Laboratory of Cellular and Molecular Biology, National Institute on Aging-IRP, National Institutes of Health, Baltimore, MD, USA
- Box 12, LCMB, NIA-IRP, NIH 5600 Nathan Shock Drive, Baltimore, MD 21224, USA. Tel.: +1 410 558 8443; Fax: +1 410 558 8386; E-mail:
| |
Collapse
|
39
|
Karapetian RN, Evstafieva AG, Abaeva IS, Chichkova NV, Filonov GS, Rubtsov YP, Sukhacheva EA, Melnikov SV, Schneider U, Wanker EE, Vartapetian AB. Nuclear oncoprotein prothymosin alpha is a partner of Keap1: implications for expression of oxidative stress-protecting genes. Mol Cell Biol 2005; 25:1089-99. [PMID: 15657435 PMCID: PMC544000 DOI: 10.1128/mcb.25.3.1089-1099.2005] [Citation(s) in RCA: 149] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2004] [Revised: 08/09/2004] [Accepted: 10/25/2004] [Indexed: 11/20/2022] Open
Abstract
Animal cells counteract oxidative stress and electrophilic attack through coordinated expression of a set of detoxifying and antioxidant enzyme genes mediated by transcription factor Nrf2. In unstressed cells, Nrf2 appears to be sequestered in the cytoplasm via association with an inhibitor protein, Keap1. Here, by using the yeast two-hybrid screen, human Keap1 has been identified as a partner of the nuclear protein prothymosin alpha. The in vivo and in vitro data indicated that the prothymosin alpha-Keap1 interaction is direct, highly specific, and functionally relevant. Furthermore, we showed that Keap1 is a nuclear-cytoplasmic shuttling protein equipped with a nuclear export signal that is important for its inhibitory action. Prothymosin alpha was able to liberate Nrf2 from the Nrf2-Keap1 inhibitory complex in vitro through competition with Nrf2 for binding to the same domain of Keap1. In vivo, the level of Nrf2-dependent transcription was correlated with the intracellular level of prothymosin alpha by using prothymosin alpha overproduction and mRNA interference approaches. Our data attribute to prothymosin alpha the role of intranuclear dissociator of the Nrf2-Keap1 complex, thus revealing a novel function for prothymosin alpha and adding a new dimension to the molecular mechanisms underlying expression of oxidative stress-protecting genes.
Collapse
Affiliation(s)
- Ruben N Karapetian
- Belozersky Institute of Physico-Chemical Biology, Moscow State University, Moscow 119992, Russia
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Karetsou Z, Martic G, Tavoulari S, Christoforidis S, Wilm M, Gruss C, Papamarcaki T. Prothymosin alpha associates with the oncoprotein SET and is involved in chromatin decondensation. FEBS Lett 2005; 577:496-500. [PMID: 15556635 DOI: 10.1016/j.febslet.2004.09.091] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2004] [Accepted: 09/23/2004] [Indexed: 11/26/2022]
Abstract
Prothymosin alpha (ProTalpha) is a histone H1-binding protein that interacts with the transcription coactivator CREB-binding protein and potentiates transcription. Based on coimmunoprecipitation and mammalian two-hybrid assays, we show here that ProTalpha forms a complex with the oncoprotein SET. ProTalpha efficiently decondenses human sperm chromatin, while overexpression of GFP-ProTalpha in mammalian cells results in global chromatin decondensation. These results indicate that decondensation of compacted chromatin fibers is an important step in the mechanism of ProTalpha function.
Collapse
Affiliation(s)
- Zoe Karetsou
- Laboratory of Biological Chemistry, Medical School, University of Ioannina, 451 10 Ioannina, Greece
| | | | | | | | | | | | | |
Collapse
|
41
|
Romanova LI, Belov GA, Lidsky PV, Tolskaya EA, Kolesnikova MS, Evstafieva AG, Vartapetian AB, Egger D, Bienz K, Agol VI. Variability in apoptotic response to poliovirus infection. Virology 2005; 331:292-306. [PMID: 15629772 DOI: 10.1016/j.virol.2004.10.038] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2004] [Revised: 08/25/2004] [Accepted: 10/21/2004] [Indexed: 12/26/2022]
Abstract
In several cell types, poliovirus activates the apoptotic program, implementation of which is suppressed by viral antiapoptotic functions. In such cells, productive infection leads to a necrotic cytopathic effect (CPE), while abortive reproduction, associated with inadequate viral antiapoptotic functions, results in apoptosis. Here, we describe two other types of cell response to poliovirus infection. Murine L20B cells expressing human poliovirus receptor responded to the infection by both CPE and apoptosis concurrently. Interruption of productive infection decreased rather than increased the proportion of apoptotic cells. Productive infection was accompanied by the early efflux of cytochrome c from the mitochondria in a proportion of cells and by activation of DEVD-specific caspases. Inactivation of caspase-9 resulted in a marked, but incomplete, prevention of the apoptotic response of these cells to viral infection. Thus, the poliovirus-triggered apoptotic program in L20B cells was not completely suppressed by the viral antiapoptotic functions. In contrast, human rhabdomyosarcoma RD cells did not develop appreciable apoptosis during productive or abortive infection, exhibiting inefficient efflux of cytochrome c from mitochondria and no marked activation of DEVD-specific caspases. The cells were also refractory to several nonviral apoptosis inducers. Nevertheless, typical caspase-dependent signs of apoptosis in a proportion of RD cells were observed after cessation of viral reproduction. Such "late" apoptosis was also observed in productively infected HeLa cells. In addition, a tiny proportion of all studied cells were TUNEL positive even in the presence of a caspase inhibitor. Degradation of DNA in such cells appeared to be a postmortem phenomenon. Biological relevance of variable host responses to viral infection is discussed.
Collapse
Affiliation(s)
- Lyudmila I Romanova
- M.P. Chumakov Institute of Poliomyelitis and Viral Encephalitides, Russian Academy of Medical Sciences, Moscow Region 142782, Russia
| | | | | | | | | | | | | | | | | | | |
Collapse
|
42
|
Yang CH, Murti A, Baker SJ, Frangou-Lazaridis M, Vartapetian AB, Murti KG, Pfeffer LM. Interferon induces the interaction of prothymosin-alpha with STAT3 and results in the nuclear translocation of the complex. Exp Cell Res 2004; 298:197-206. [PMID: 15242774 DOI: 10.1016/j.yexcr.2004.04.008] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2003] [Revised: 03/05/2004] [Indexed: 11/21/2022]
Abstract
Interferons (IFNs) play critical roles in host defense by modulating the expression of various genes via tyrosine phosphorylation of STAT transcription factors. Many cytokines including IFNs induce tyrosine phosphorylation of the STAT3 transcription factor, which regulates acute phase gene expression. Using the yeast two-hybrid interaction trap, in which a tyrosine kinase is introduced into the yeast to allow tyrosine phosphorylation of bait proteins, prothymosin-alpha (ProTalpha) was identified to interact with the amino terminal half of tyrosine-phosphorylated STAT3. ProTalpha is a small, acidic, extremely abundant, and essential protein that may play a role in chromatin remodeling, and has been implicated in regulating the growth and survival of mammalian cells. Besides the interaction of tyrosine-phosphorylated STAT3 with ProTalpha in yeast cells, IFN induced the interaction of ProTalpha with STAT3 in mammalian cells, and this interaction was dependent on the tyrosine phosphorylation of STAT3. Moreover, IFNalpha induces the translocation of STAT3 and ProTalpha from the cytoplasm to the nucleus where these proteins colocalize. Since ProTalpha has an extremely strong nuclear localization and STAT proteins apparently lack any nuclear localization signals, the association of STAT3 with ProTalpha may provide a mechanism to result in STAT localization in the nucleus.
Collapse
Affiliation(s)
- Chuan He Yang
- Department of Pathology and Laboratory Medicine, University of Tennessee Health Science Center, Memphis 38103, USA
| | | | | | | | | | | | | |
Collapse
|
43
|
Nomura S, Baxter T, Yamaguchi H, Leys C, Vartapetian AB, Fox JG, Lee JR, Wang TC, Goldenring JR. Spasmolytic polypeptide expressing metaplasia to preneoplasia in H. felis-infected mice. Gastroenterology 2004; 127:582-94. [PMID: 15300590 DOI: 10.1053/j.gastro.2004.05.029] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND & AIMS The emergence of oxyntic atrophy and metaplastic cell lineages in response to chronic Helicobacter pylori infection predisposes to gastric neoplasia. We have described a trefoil factor family 2 (TFF2; spasmolytic polypeptide) expressing metaplasia (SPEM) associated with gastric neoplasia in both rodent and human fundus. To examine the relationship of SPEM to the neoplastic process in the H. felis -infected C57BL/6 mouse, we have now studied the association of SPEM-related transcripts with preneoplasia. METHODS SPEM-related transcripts were identified by microarray analysis of amplified cRNA from SPEM, and surface mucous cells were isolated by laser capture microdissection from the same gastric sections from male C57BL/6 mice infected with H. felis for 6 months. Expression of SPEM-related transcripts was assessed by in situ hybridization and quantitative RT-PCR, as well as immunohistochemistry for prothymosin alpha. RESULTS Eleven SPEM-related transcripts were identified as detectable only in SPEM. The expression of the SPEM-related transcripts was validated by in situ hybridization and quantitative PCR. One transcript, the noncoding RNA Xist, was only identified in SPEM cells from the infected male mice. Ten of the 11 transcripts as well as TFF2 were also expressed in regions of gastritis cystica profunda. Immunocytochemistry for one of the identified proteins, prothymosin alpha, demonstrated prominent nuclear staining in SPEM and gastritis cystica profunda. CONCLUSIONS The expression of SPEM-related transcripts in regions of gastritis cystica profunda suggests that SPEM represents a precursor lineage for the development of dysplasia in this animal model of gastric carcinogenesis.
Collapse
Affiliation(s)
- Sachiyo Nomura
- Nashville VA Medical Center and the Department of Surgery, Vanderbilt-Ingram Cancer Center, Vanderbilt University School of Medicine, Tennessee, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Brown KJ, Fenselau C. Investigation of Doxorubicin Resistance in MCF-7 Breast Cancer Cells Using Shot-Gun Comparative Proteomics with Proteolytic 18O Labeling. J Proteome Res 2004; 3:455-62. [PMID: 15253426 DOI: 10.1021/pr0340835] [Citation(s) in RCA: 62] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A shot-gun comparative proteomic investigation utilizing proteolytic 18O labeling has been carried out on a drug susceptible MCF-7 human breast cancer cell line and a related cell line that is resistant to doxorubicin. The proteolytic 18O labeling method has been further refined and optimized for application to a protein fraction stemming from the cytosol of the breast cancer cells. The comparative investigation revealed several proteins with altered expression levels in the doxorubicin resistant line. These altered proteins are considered for a possible role in doxorubicin resistance.
Collapse
Affiliation(s)
- Kristy J Brown
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
| | | |
Collapse
|