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Li H, Wu J, Zhang N, Zheng Q. Transglutaminase 2-mediated histone monoaminylation and its role in cancer. Biosci Rep 2024; 44:BSR20240493. [PMID: 39115570 PMCID: PMC11345673 DOI: 10.1042/bsr20240493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2024] [Revised: 08/07/2024] [Accepted: 08/08/2024] [Indexed: 08/10/2024] Open
Abstract
Transglutaminase 2 (TGM2) has been known as a well-characterized factor regulating the progression of multiple types of cancer, due to its multifunctional activities and the ubiquitous signaling pathways it is involved in. As a member of the transglutaminase family, TGM2 catalyzes protein post-translational modifications (PTMs), including monoaminylation, amide hydrolysis, cross-linking, etc., through the transamidation of variant glutamine-containing protein substrates. Recent discoveries revealed histone as an important category of TGM2 substrates, thus identifying histone monoaminylation as an emerging epigenetic mark, which is highly enriched in cancer cells and possesses significant regulatory functions of gene transcription. In this review, we will summarize recent advances in TGM2-mediated histone monoaminylation as well as its role in cancer and discuss the key research methodologies to better understand this unique epigenetic mark, thereby shedding light on the therapeutic potential of TGM2 as a druggable target in cancer treatment.
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Affiliation(s)
- Huapeng Li
- Molecular, Cellular, and Developmental Biology Graduate Program, The Ohio State University, Columbus, OH 43210, U.S.A
- Department of Radiation Oncology, College of Medicine, The Ohio State University, Columbus, OH 43210, U.S.A
- Center for Cancer Metabolism, James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Jinghua Wu
- Department of Radiation Oncology, College of Medicine, The Ohio State University, Columbus, OH 43210, U.S.A
- Center for Cancer Metabolism, James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Nan Zhang
- Department of Radiation Oncology, College of Medicine, The Ohio State University, Columbus, OH 43210, U.S.A
- Center for Cancer Metabolism, James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, U.S.A
| | - Qingfei Zheng
- Molecular, Cellular, and Developmental Biology Graduate Program, The Ohio State University, Columbus, OH 43210, U.S.A
- Department of Radiation Oncology, College of Medicine, The Ohio State University, Columbus, OH 43210, U.S.A
- Center for Cancer Metabolism, James Comprehensive Cancer Center, The Ohio State University, Columbus, OH 43210, U.S.A
- Department of Biological Chemistry and Pharmacology, College of Medicine, The Ohio State University, Columbus, OH 43210, U.S.A
- Department of Medicinal Chemistry and Molecular Pharmacology, College of Pharmacy, Purdue University, IN, U.S.A
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2
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Navals P, Rangaswamy AMM, Kasyanchyk P, Berezovski MV, Keillor JW. Conformational Modulation of Tissue Transglutaminase via Active Site Thiol Alkylating Agents: Size Does Not Matter. Biomolecules 2024; 14:496. [PMID: 38672511 PMCID: PMC11048362 DOI: 10.3390/biom14040496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2024] [Revised: 04/02/2024] [Accepted: 04/17/2024] [Indexed: 04/28/2024] Open
Abstract
TG2 is a unique member of the transglutaminase family as it undergoes a dramatic conformational change, allowing its mutually exclusive function as either a cross-linking enzyme or a G-protein. The enzyme's dysregulated activity has been implicated in a variety of pathologies (e.g., celiac disease, fibrosis, cancer), leading to the development of a wide range of inhibitors. Our group has primarily focused on the development of peptidomimetic targeted covalent inhibitors, the nature and size of which were thought to be important features to abolish TG2's conformational dynamism and ultimately inhibit both its activities. However, we recently demonstrated that the enzyme was unable to bind guanosine triphosphate (GTP) when catalytically inactivated by small molecule inhibitors. In this study, we designed a library of models targeting covalent inhibitors of progressively smaller sizes (15 to 4 atoms in length). We evaluated their ability to inactivate TG2 by measuring their respective kinetic parameters kinact and KI. Their impact on the enzyme's ability to bind GTP was then evaluated and subsequently correlated to the conformational state of the enzyme, as determined via native PAGE and capillary electrophoresis. All irreversible inhibitors evaluated herein locked TG2 in its open conformation and precluded GTP binding. Therefore, we conclude that steric bulk and structural complexity are not necessary factors to consider when designing TG2 inhibitors to abolish G-protein activity.
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Affiliation(s)
| | | | | | | | - Jeffrey W. Keillor
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, ON K1N 6N5, Canada; (P.N.); (A.M.M.R.); (P.K.); (M.V.B.)
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3
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Kolligundla LP, Gupta S, Lata S, Mulukala SKN, Killaka P, Akif M, Pasupulati AK. Identification of Novel GTP Analogs as Potent and Specific Reversible Inhibitors for Transglutaminase 2. MOLECULAR SIMULATION 2022. [DOI: 10.1080/08927022.2022.2123917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Affiliation(s)
- Lakshmi P. Kolligundla
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Samriddhi Gupta
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Surabhi Lata
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Sandeep K. N. Mulukala
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Praneeth Killaka
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Mohd Akif
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
| | - Anil K. Pasupulati
- Department of Biochemistry, School of Life Sciences, University of Hyderabad, Hyderabad, India
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4
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Al-U'datt DGF, Tranchant CC, Al-Dwairi A, AlQudah M, Al-Shboul O, Hiram R, Allen BG, Jaradat S, Alqbelat J, Abu-Zaiton AS. Implications of enigmatic transglutaminase 2 (TG2) in cardiac diseases and therapeutic developments. Biochem Pharmacol 2022; 201:115104. [PMID: 35617996 DOI: 10.1016/j.bcp.2022.115104] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2022] [Revised: 05/18/2022] [Accepted: 05/18/2022] [Indexed: 01/07/2023]
Abstract
Cardiac diseases are the leading cause of mortality and morbidity worldwide. Mounting evidence suggests that transglutaminases (TGs), tissue TG (TG2) in particular, are involved in numerous molecular responses underlying the pathogenesis of cardiac diseases. The TG family has several intra- and extracellular functions in the human body, including collagen cross-linking, angiogenesis, cell growth, differentiation, migration, adhesion as well as survival. TGs are thiol- and calcium-dependent acyl transferases that catalyze the formation of a covalent bond between the γ-carboxamide group of a glutamine residue and an amine group, thus increasing the stability, rigidity, and stiffness of the myocardial extracellular matrix (ECM). Excessive accumulation of cross-linked collagen leads to increase myocardial stiffness and fibrosis. Beyond TG2 extracellular protein cross-linking action, mounting evidence suggests that this pleiotropic TG isozyme may also promote fibrotic diseases through cell survival and profibrotic pathway activation at the signaling, transcriptional and translational levels. Due to its multiple functions and localizations, TG2 fulfils critical yet incompletely understood roles in myocardial fibrosis and associated heart diseases, such as cardiac hypertrophy, heart failure, and age-related myocardial stiffness under several conditions. This review summarizes current knowledge and existing gaps regarding the ECM-dependent and ECM-independent roles of TG2 and highlights the therapeutic prospects of targeting TG2 to treat cardiac diseases.
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Affiliation(s)
- Doa'a G F Al-U'datt
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan.
| | - Carole C Tranchant
- School of Food Science, Nutrition and Family Studies, Faculty of Health Sciences and Community Services, Université de Moncton, New Brunswick, Canada
| | - Ahmed Al-Dwairi
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Mohammad AlQudah
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Othman Al-Shboul
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Roddy Hiram
- Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada; Department of Medicine, Université de Montréal, Montreal, Quebec, Canada
| | - Bruce G Allen
- Montreal Heart Institute, Université de Montréal, Montreal, Quebec, Canada; Department of Medicine, Université de Montréal, Montreal, Quebec, Canada; Department of Pharmacology and Physiology, Université de Montréal, Montreal, Quebec, Canada; Department of Biochemistry and Molecular Medicine, Université de Montréal, Montreal, Quebec, Canada
| | - Saied Jaradat
- Princess Haya Biotechnology Center, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Jenan Alqbelat
- Department of Physiology and Biochemistry, Faculty of Medicine, Jordan University of Science and Technology, Irbid, 22110, Jordan
| | - Ahmed S Abu-Zaiton
- Department of Biological Sciences, Al al-bayt University, Al-Mafraq, Jordan
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5
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Staffler R, Pasternack R, Hils M, Kaiser W, Möller FM. Nucleotide binding kinetics and conformational change analysis of tissue transglutaminase with switchSENSE. Anal Biochem 2020; 605:113719. [PMID: 32697952 DOI: 10.1016/j.ab.2020.113719] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 02/17/2020] [Accepted: 04/03/2020] [Indexed: 01/06/2023]
Abstract
Function, activity, and interactions of proteins crucially depend on their three-dimensional structure and are often regulated by effector binding and environmental changes. Tissue transglutaminase (Transglutaminase 2, TG2) is a multifunctional protein, allosterically regulated by nucleotides and Ca2+ ions, which trigger opposing conformational changes. Here we introduce switchSENSE as a versatile tool for TG2 characterization and provide novel insights into protein conformation as well as analyte binding kinetics. For the first time, we succeeded in measuring the kinetic rate constants and affinities (kon, koff, KD) for guanosine nucleotides (GMP, GDP, GTP, GTPγS). Further, the conformational changes induced by GDP, Ca2+ and the covalent inhibitor Z-DON were observed by changes in TG2's hydrodynamic diameter. We confirmed the well-known compaction by guanosine nucleotides and extension by Ca2+, and provide evidence for TG2 conformations so far not described by structural analysis. Moreover, we analyze the influence of the peptidic Z-DON inhibitor and the R580A mutation on the conformational responsiveness of TG2 to its natural effectors. In summary, this work shows how the combination of structural and kinetic information obtained by switchSENSE opens new perspectives for the characterization of conformationally active proteins and their interactions with ligands, e.g. potential drug candidates.
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Affiliation(s)
- Regina Staffler
- Dynamic Biosensors GmbH, Lochhamer Str. 15, 82152, Martinsried, Germany
| | | | - Martin Hils
- Zedira GmbH, Roesslerstrasse 83, 64293, Darmstadt, Germany
| | - Wolfgang Kaiser
- Dynamic Biosensors GmbH, Lochhamer Str. 15, 82152, Martinsried, Germany
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Zhuang R, Khosla C. Substrates, inhibitors, and probes of mammalian transglutaminase 2. Anal Biochem 2020; 591:113560. [PMID: 31874171 PMCID: PMC6948143 DOI: 10.1016/j.ab.2019.113560] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 12/15/2019] [Accepted: 12/20/2019] [Indexed: 02/07/2023]
Abstract
Transglutaminase 2 (TG2) is a ubiquitous but enigmatic mammalian protein to which a number of biological functions have been ascribed but not definitively proven. As a member of the transglutaminase family, TG2 can catalyze deamidation or alternatively transamidation of selected Gln residues in proteins and peptides. It is also known to harbor other enzymatic properties, including protein disulfide isomerase, GTP-dependent signal transduction, and ATP dependent protein kinase activity. Given its multifunctional chemistry, it is unsurprising that a long list of proteins from the mammalian proteome have been identified as substrates and/or binding partners; however, the biological relevance of none of these protein-protein interactions has been clarified as yet. Remarkably, the most definitive insights into the biology of TG2 stem from its pathophysiological role in gluten peptide deamidation in celiac disease. Meanwhile our understanding of TG2 chemistry has been leveraged to engineer a spectrum of inhibitors and other molecular probes of TG2 biology in vivo. This review summarizes our current knowledge of the enzymology and regulation of human TG2 with a focus on its physiological substrates as well as tool molecules whose engineering was inspired by their identities.
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Affiliation(s)
- Ruize Zhuang
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA
| | - Chaitan Khosla
- Department of Chemical Engineering, Stanford University, Stanford, CA, USA; Department of Chemistry, Stanford University, Stanford, CA, USA; Stanford ChEM-H, Stanford University, Stanford, CA, USA.
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7
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Competitive Binding of Magnesium to Calcium Binding Sites Reciprocally Regulates Transamidase and GTP Hydrolysis Activity of Transglutaminase 2. Int J Mol Sci 2020; 21:ijms21030791. [PMID: 31991788 PMCID: PMC7037829 DOI: 10.3390/ijms21030791] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Revised: 01/17/2020] [Accepted: 01/23/2020] [Indexed: 02/07/2023] Open
Abstract
Transglutaminase 2 (TG2) is a Ca2+-dependent enzyme, which regulates various cellular processes by catalyzing protein crosslinking or polyamination. Intracellular TG2 is activated and inhibited by Ca2+ and GTP binding, respectively. Although aberrant TG2 activation has been implicated in the pathogenesis of diverse diseases, including cancer and degenerative and fibrotic diseases, the structural basis for the regulation of TG2 by Ca2+ and GTP binding is not fully understood. Here, we produced and analyzed a Ca2+-containing TG2 crystal, and identified two glutamate residues, E437 and E539, as Ca2+-binding sites. The enzymatic analysis of the mutants revealed that Ca2+ binding to these sites is required for the transamidase activity of TG2. Interestingly, we found that magnesium (Mg2+) competitively binds to the E437 and E539 residues. The Mg2+ binding to these allosteric sites enhances the GTP binding/hydrolysis activity but inhibits transamidase activity. Furthermore, HEK293 cells transfected with mutant TG2 exhibited higher transamidase activity than cells with wild-type TG2. Cells with wild-type TG2 showed an increase in transamidase activity under Mg2+-depleted conditions, whereas cells with mutant TG2 were unaffected. These results indicate that E437 and E539 are Ca2+-binding sites contributing to the reciprocal regulation of transamidase and GTP binding/hydrolysis activities of TG2 through competitive Mg2+ binding.
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8
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Biocatalysis by Transglutaminases: A Review of Biotechnological Applications. MICROMACHINES 2018; 9:mi9110562. [PMID: 30715061 PMCID: PMC6265872 DOI: 10.3390/mi9110562] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Accepted: 10/23/2018] [Indexed: 02/08/2023]
Abstract
The biocatalytic activity of transglutaminases (TGs) leads to the synthesis of new covalent isopeptide bonds (crosslinks) between peptide-bound glutamine and lysine residues, but also the transamidation of primary amines to glutamine residues, which ultimately can result into protein polymerisation. Operating with a cysteine/histidine/aspartic acid (Cys/His/Asp) catalytic triad, TGs induce the post-translational modification of proteins at both physiological and pathological conditions (e.g., accumulation of matrices in tissue fibrosis). Because of the disparate biotechnological applications, this large family of protein-remodelling enzymes have stimulated an escalation of interest. In the past 50 years, both mammalian and microbial TGs polymerising activity has been exploited in the food industry for the improvement of aliments' quality, texture, and nutritive value, other than to enhance the food appearance and increased marketability. At the same time, the ability of TGs to crosslink extracellular matrix proteins, like collagen, as well as synthetic biopolymers, has led to multiple applications in biomedicine, such as the production of biocompatible scaffolds and hydrogels for tissue engineering and drug delivery, or DNA-protein bio-conjugation and antibody functionalisation. Here, we summarise the most recent advances in the field, focusing on the utilisation of TGs-mediated protein multimerisation in biotechnological and bioengineering applications.
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10
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Reyna-Beltrán E, Iranzo M, Calderón-González KG, Mondragón-Flores R, Labra-Barrios ML, Mormeneo S, Luna-Arias JP. The Candida albicans ENO1 gene encodes a transglutaminase involved in growth, cell division, morphogenesis, and osmotic protection. J Biol Chem 2018; 293:4304-4323. [PMID: 29386353 PMCID: PMC5868267 DOI: 10.1074/jbc.m117.810440] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 12/13/2017] [Indexed: 12/19/2022] Open
Abstract
Candida albicans is an opportunistic fungus that is part of the normal microflora commonly found in the human digestive tract and the normal mucosa or skin of healthy individuals. However, in immunocompromised individuals, it becomes a serious health concern and a threat to their lives and is ranked as the leading fungal infection in humans worldwide. As existing treatments for this infection are non-specific or under threat of developing resistance, there is a dire necessity to find new targets for designing specific drugs to defeat this fungus. Some authors reported the presence of the transglutaminase activity in Candida and Saccharomyces, but its identity remains unknown. We report here the phenotypic effects produced by the inhibition of transglutaminase enzymatic activity with cystamine, including growth inhibition of yeast cells, induction of autophagy in response to damage caused by cystamine, alteration of the normal yeast division pattern, changes in cell wall, and inhibition of the yeast-to-mycelium transition. The latter phenomenon was also observed in the C. albicans ATCC 26555 strain. Growth inhibition by cystamine was also determined in other Candida strains, demonstrating the importance of transglutaminase in these species. Finally, we identified enolase 1 as the cell wall protein responsible for TGase activity. After studying the inhibition of enzymatic activities with anti-CaEno1 antibodies and through bioinformatics studies, we suggest that the enolase and transglutaminase catalytic sites are localized in different domains of the protein. The aforementioned data indicate that TGase/Eno1 is a putative target for designing new drugs to control C. albicans infection.
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Affiliation(s)
| | - María Iranzo
- the Department de Microbiologia i Ecologia, Facultad de Farmacia, Unidad de Microbiología, Universitat de València, 46100 Valencia, España
| | | | - Ricardo Mondragón-Flores
- Bioquímica, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional (Cinvestav-IPN), C.P. 07360, Ciudad de México, México and
| | | | - Salvador Mormeneo
- the Department de Microbiologia i Ecologia, Facultad de Farmacia, Unidad de Microbiología, Universitat de València, 46100 Valencia, España
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11
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Endothelial cell-surface tissue transglutaminase inhibits neutrophil adhesion by binding and releasing nitric oxide. Sci Rep 2017; 7:16163. [PMID: 29170410 PMCID: PMC5701052 DOI: 10.1038/s41598-017-16342-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Accepted: 11/10/2017] [Indexed: 02/03/2023] Open
Abstract
Nitric oxide (NO) produced by endothelial cells in response to cytokines displays anti-inflammatory activity by preventing the adherence, migration and activation of neutrophils. The molecular mechanism by which NO operates at the blood-endothelium interface to exert anti-inflammatory properties is largely unknown. Here we show that on endothelial surfaces, NO is associated with the sulfhydryl-rich protein tissue transglutaminase (TG2), thereby endowing the membrane surfaces with anti-inflammatory properties. We find that tumor necrosis factor-α-stimulated neutrophil adherence is opposed by TG2 molecules that are bound to the endothelial surface. Alkylation of cysteine residues in TG2 or inhibition of endothelial NO synthesis renders the surface-bound TG2 inactive, whereas specific, high affinity binding of S-nitrosylated TG2 (SNO-TG2) to endothelial surfaces restores the anti-inflammatory properties of the endothelium, and reconstitutes the activity of endothelial-derived NO. We also show that SNO-TG2 is present in healthy tissues and that it forms on the membranes of shear-activated endothelial cells. Thus, the anti-inflammatory mechanism that prevents neutrophils from adhering to endothelial cells is identified with TG2 S-nitrosylation at the endothelial cell-blood interface.
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Sivadó É, Lareure S, Attuil-Audenis V, Alaoui SE, Thomas V. Development of a sandwich ELISA assay for quantification of human tissue transglutaminase in cell lysates and tissue homogenates. Amino Acids 2016; 49:597-604. [PMID: 27761757 DOI: 10.1007/s00726-016-2347-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2016] [Accepted: 10/04/2016] [Indexed: 12/17/2022]
Abstract
Tissue transglutaminase (tTG) belongs to the multigene transglutaminase family of Ca2+-dependent protein cross-linking enzymes. There is a strong evidence that tTG is involved in pathology, such as neurodegenerative diseases, cancer, and celiac disease. To study physiopathological implication of tTG, a sandwich immunoassay has been developed with a new monoclonal antibody for the capture and polyclonal antibody both generated in house. Using this ready to use assay, the tTG protein level can be measured in human tissue homogenates and cells extracts easily in about 4 h. The limit of detection is 1.7 ng/ml; the coefficients of intra- and inter-assay variations range from 1 to 2 % and from 7 to 10 %, respectively. The assay is specific to tTG, and no cross reactivity with TG1, TG3, TG6, TG7, or factor XIIIa was observed. Finally, in the addition to the tTG activity assay previously developed, this assay should be a valuable tool to increase our knowledge of the tTG involvement in physiological and pathological states.
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Affiliation(s)
- Éva Sivadó
- Research Department, Covalab S.A.S, 11 Avenue Albert Einstein, 69100, Villeurbanne, France
| | - Sabrina Lareure
- Research Department, Covalab S.A.S, 11 Avenue Albert Einstein, 69100, Villeurbanne, France
| | - Valérie Attuil-Audenis
- Research Department, Covalab S.A.S, 11 Avenue Albert Einstein, 69100, Villeurbanne, France
| | - Saïd El Alaoui
- Research Department, Covalab S.A.S, 11 Avenue Albert Einstein, 69100, Villeurbanne, France
| | - Vincent Thomas
- Research Department, Covalab S.A.S, 11 Avenue Albert Einstein, 69100, Villeurbanne, France.
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13
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van der Wildt B, Lammertsma AA, Drukarch B, Windhorst AD. Strategies towards in vivo imaging of active transglutaminase type 2 using positron emission tomography. Amino Acids 2016; 49:585-595. [PMID: 27380031 PMCID: PMC5332496 DOI: 10.1007/s00726-016-2288-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Accepted: 06/22/2016] [Indexed: 01/04/2023]
Abstract
Transglutaminase type 2 (TG2) is increasingly linked to the pathogenesis of several diseases, such as celiac disease, cancer, and fibrotic and neurodegenerative diseases. In parallel with becoming an attractive target for therapy, interest in the development of compounds for in vivo imaging of TG2 is rising. Such imaging biomarkers might assist in clarifying the role of TG2 in pathology and in monitoring TG2 inhibition in vivo and thus assist in drug development. In this review, the latest results together with various strategies in TG2 PET tracer development are discussed, including radiolabelling of irreversible and reversible active-site inhibitors, as well as allosteric inhibitors, acyl-donor and acyl-acceptor substrates, and anti-TG2 monoclonal antibodies.
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Affiliation(s)
- Berend van der Wildt
- Departments of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands.
- Departments of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, The Netherlands.
| | - Adriaan A Lammertsma
- Departments of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
| | - Benjamin Drukarch
- Departments of Anatomy and Neurosciences, VU University Medical Center, Amsterdam, The Netherlands
| | - Albert D Windhorst
- Departments of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, The Netherlands
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14
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Lai TS, Lin CJ, Greenberg CS. Role of tissue transglutaminase-2 (TG2)-mediated aminylation in biological processes. Amino Acids 2016; 49:501-515. [PMID: 27270573 DOI: 10.1007/s00726-016-2270-8] [Citation(s) in RCA: 35] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 05/31/2016] [Indexed: 01/08/2023]
Abstract
Post-translational modification (PTM) is an important mechanism in modulating a protein's structure and can lead to substantial diversity in biological function. Compared to other forms of PTMs such as phosphorylation, acetylation and glycosylation, the physiological significance of aminylation is limited. Aminylation refers to the covalent incorporation of biogenic/polyamines into target protein by calcium-dependent transglutaminases (TGs). The development of novel and more sensitive techniques has led to more proteins identified as tissue transglutaminase (TG2) substrates and potential targets for aminylation. Many of these substrate proteins play a role in cell signaling, cytoskeleton organization, muscle contraction, and inflammation. TG2 is well studied and widely expressed in a variety of tissues and will be the primary focus of this review on recent advance in transglutaminase-mediated aminylation.
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Affiliation(s)
- Thung-S Lai
- Graduate Institute of Biomedical Science, Mackay Medical College, No. 46, Sec. 3, Jhong-Jheng Rd., Sanzhi Dist, New Taipei City, 25200, Taiwan, ROC.
| | - Cheng-Jui Lin
- Nephrology/Department of Internal Medicine, Mackay Memorial Hospital, Taipei, Taiwan, ROC
- Nursing and Management, Mackay Junior College of Medicine, Taipei, Taiwan, ROC
| | - Charles S Greenberg
- Department of Medicine, Medical University of South Carolina, Charleston, SC, 29425, USA
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15
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Hauser C, Wodtke R, Löser R, Pietsch M. A fluorescence anisotropy-based assay for determining the activity of tissue transglutaminase. Amino Acids 2016; 49:567-583. [PMID: 26886924 DOI: 10.1007/s00726-016-2192-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 02/02/2016] [Indexed: 01/10/2023]
Abstract
Tissue transglutaminase (TGase 2) is the most abundantly expressed enzyme of the transglutaminase family and involved in a large variety of pathological processes, such as neurodegenerative diseases, disorders related to autoimmunity and inflammation as well as tumor growth, progression and metastasis. As a result, TGase 2 represents an attractive target for drug discovery and development, which requires assays that allow for the characterization of modulating agents and are appropriate for high-throughput screening. Herein, we report a fluorescence anisotropy-based approach for the determination of TGase 2's transamidase activity, following the time-dependent increase in fluorescence anisotropy due to the enzyme-catalyzed incorporation of fluorescein- and rhodamine B-conjugated cadaverines 1-3 (acyl acceptor substrates) into N,N-dimethylated casein (acyl donor substrate). These cadaverine derivatives 1-3 were obtained by solid-phase synthesis. To allow efficient conjugation of the rhodamine B moiety, different linkers providing secondary amine functions, such as sarcosyl and isonipecotyl, were introduced between the cadaverine and xanthenyl entities in compounds 2 and 3, respectively, with acyl acceptor 3 showing the most optimal substrate properties of the compounds investigated. The assay was validated for the search of both irreversible and reversible TGase 2 inhibitors using the inactivators iodoacetamide and a recently published L-lysine-derived acrylamide and the allosteric binder GTP, respectively. In addition, the fluorescence anisotropy-based method was proven to be suitable for high-throughput screening (Z' factor of 0.86) and represents a non-radioactive and highly sensitive assay for determining the active TGase 2 concentration.
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Affiliation(s)
- Christoph Hauser
- Center of Pharmacology, Medical Faculty, University of Cologne, Gleueler Str. 24, 50931, Cologne, Germany
| | - Robert Wodtke
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstr. 400, 01328, Dresden, Germany
- Department of Chemistry and Food Chemistry, Technical University Dresden, Mommsenstraße 4, 01062, Dresden, Germany
| | - Reik Löser
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, Bautzner Landstr. 400, 01328, Dresden, Germany.
- Department of Chemistry and Food Chemistry, Technical University Dresden, Mommsenstraße 4, 01062, Dresden, Germany.
| | - Markus Pietsch
- Center of Pharmacology, Medical Faculty, University of Cologne, Gleueler Str. 24, 50931, Cologne, Germany.
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16
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Norsa L, Tomba C, Agostoni C, Branchi F, Bardella MT, Roncoroni L, Conte D, Elli L. Gluten-free diet or alternative therapy: a survey on what parents of celiac children want. Int J Food Sci Nutr 2015; 66:590-4. [PMID: 26171630 DOI: 10.3109/09637486.2015.1064872] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
OBJECTIVES Celiac disease (CD) is treated by life-long gluten-free diet (GFD). Novel therapies are under development. Willingness of CD children's parents to alternative therapies and GFD impact were evaluated. METHODS Parents of celiac children on GFD were investigated on need and preference for novel CD therapies, children's enrolment in trials, compliance to and personal judgment on GFD, health status (HS) and quality of life (QoL). RESULTS About 59.5% surveyed parents expressed the need for alternative therapies with a preference for vaccine-based strategy (39.9%). About 37.7% would accept enrollment in an ad hoc trial, 20.3% would agree to endoscopy during the trial. GFD compliance was 97.4% and well accepted by 93.8%. HS and QoL significantly improved during GFD (p < 0.001). CONCLUSIONS The introduction of novel therapies for CD is desirable for over half of parents, with preference for vaccines. Parents frown upon enrolment in new clinical trials and the subsequent need for additional endoscopy.
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Affiliation(s)
- Lorenzo Norsa
- Center for the Prevention and Diagnosis of Celiac Disease, Gastroenterology and Digestive Endoscopy Unit, Department of Pathophysiology and Transplantation, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico Milano, University of Milan , Milan , Italy and
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17
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Inhibitors of tissue transglutaminase. Trends Pharmacol Sci 2014; 36:32-40. [PMID: 25500711 DOI: 10.1016/j.tips.2014.10.014] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2014] [Revised: 10/23/2014] [Accepted: 10/30/2014] [Indexed: 02/07/2023]
Abstract
Tissue transglutaminase (TG2) catalyzes the cross-linking of proteins by the formation of isopeptide bonds between glutamine (Gln) and lysine (Lys) side chains. Although TG2 is essential for the stabilization of the extracellular matrix, its unregulated activity has been implicated in celiac disease, fibrosis, and cancer metastasis, among other disorders. Given the importance and range of TG2-related pathologies, recent work has focused on the development of potent and selective inhibitors against TG2. In this review, we present the latest and most noteworthy irreversible and reversible inhibitors of TG2, and offer perspectives for the design of future inhibitors, in the hope that lead compounds with therapeutic potential may soon be discovered.
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18
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Sulic AM, Kurppa K, Rauhavirta T, Kaukinen K, Lindfors K. Transglutaminase as a therapeutic target for celiac disease. Expert Opin Ther Targets 2014; 19:335-48. [PMID: 25410283 DOI: 10.1517/14728222.2014.985207] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
INTRODUCTION The only current treatment for celiac disease is a strict gluten-free diet. The ubiquitous presence of gluten in groceries, however, makes the diet burdensome and difficult to maintain, and alternative treatment options are thus needed. Here, the important role of transglutaminase 2 (TG2) in the pathogenesis of celiac disease makes it an attractive target for drug development. AREAS COVERED The present paper gives an overview of TG2 and addresses its significance in the pathogenesis of celiac disease. Moreover, the article summarizes preclinical studies performed with TG2 inhibitors and scrutinizes issues related to this therapeutic approach. EXPERT OPINION Activation of TG2 in the intestinal mucosa is central in celiac disease pathogenesis and researchers have therefore suggested TG2 inhibitors as a potential therapeutic approach. However, a prerequisite for such a drug is that it should be specific for TG2 and not affect the activity of other members of the transglutaminase family. Such compounds have already been introduced and tested in vitro, but a major obstacle to further development is the lack of a well-defined animal model for celiac disease. Nonetheless, with encouraging results in preclinical studies clinical trials with TG2 inhibitors are eagerly awaited.
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Affiliation(s)
- Ana-Marija Sulic
- Tampere Center for Child Health Research, University of Tampere and Tampere University Hospital , Tampere , Finland +358 50 3186306; +358 3 3641369 ;
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19
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Abstract
Tissue transglutaminase (transglutaminase 2) is a multifunctional enzyme with many interesting properties resulting in versatile roles in both physiology and pathophysiology. Herein, the particular involvement of the enzyme in human diseases will be outlined with special emphasis on its role in cancer and in tissue interactions with biomaterials. Despite recent progress in unraveling the different cellular functions of transglutaminase 2, several questions remain. Transglutaminase 2 features in both confirmed and some still ambiguous roles within pathological conditions, raising interest in developing inhibitors and imaging probes which target this enzyme. One important prerequisite for identifying and characterizing such molecular tools are reliable assay methods to measure the enzymatic activity. This digest Letter will provide clarification about the various assay methods described to date, accompanied by a discussion of recent progress in the development of inhibitors and imaging probes targeting transglutaminase 2.
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20
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Menalled LB, Kudwa AE, Oakeshott S, Farrar A, Paterson N, Filippov I, Miller S, Kwan M, Olsen M, Beltran J, Torello J, Fitzpatrick J, Mushlin R, Cox K, McConnell K, Mazzella M, He D, Osborne GF, Al-Nackkash R, Bates GP, Tuunanen P, Lehtimaki K, Brunner D, Ghavami A, Ramboz S, Park L, Macdonald D, Munoz-Sanjuan I, Howland D. Genetic deletion of transglutaminase 2 does not rescue the phenotypic deficits observed in R6/2 and zQ175 mouse models of Huntington's disease. PLoS One 2014; 9:e99520. [PMID: 24955833 PMCID: PMC4067284 DOI: 10.1371/journal.pone.0099520] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 05/13/2014] [Indexed: 11/18/2022] Open
Abstract
Huntington's disease (HD) is an autosomal dominant, progressive neurodegenerative disorder caused by expansion of CAG repeats in the huntingtin gene. Tissue transglutaminase 2 (TG2), a multi-functional enzyme, was found to be increased both in HD patients and in mouse models of the disease. Furthermore, beneficial effects have been reported from the genetic ablation of TG2 in R6/2 and R6/1 mouse lines. To further evaluate the validity of this target for the treatment of HD, we examined the effects of TG2 deletion in two genetic mouse models of HD: R6/2 CAG 240 and zQ175 knock in (KI). Contrary to previous reports, under rigorous experimental conditions we found that TG2 ablation had no effect on either motor or cognitive deficits, or on the weight loss. In addition, under optimal husbandry conditions, TG2 ablation did not extend R6/2 lifespan. Moreover, TG2 deletion did not change the huntingtin aggregate load in cortex or striatum and did not decrease the brain atrophy observed in either mouse line. Finally, no amelioration of the dysregulation of striatal and cortical gene markers was detected. We conclude that TG2 is not a valid therapeutic target for the treatment of HD.
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Affiliation(s)
| | - Andrea E. Kudwa
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Steve Oakeshott
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Andrew Farrar
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Neil Paterson
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Igor Filippov
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Sam Miller
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Mei Kwan
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Michael Olsen
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Jose Beltran
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Justin Torello
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Jon Fitzpatrick
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Richard Mushlin
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Kimberly Cox
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Kristi McConnell
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Matthew Mazzella
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Dansha He
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Georgina F. Osborne
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | - Rand Al-Nackkash
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | - Gill P. Bates
- Department of Medical and Molecular Genetics, King's College London, London, United Kingdom
| | - Pasi Tuunanen
- Charles River Discovery Research Services, Kuopio, Finland
| | | | - Dani Brunner
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Afshin Ghavami
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Sylvie Ramboz
- PsychoGenics Inc., Tarrytown, New York, United States of America
| | - Larry Park
- CHDI Management/CHDI Foundation, Princeton, New Jersey, United States of America
| | - Douglas Macdonald
- CHDI Management/CHDI Foundation, Princeton, New Jersey, United States of America
| | | | - David Howland
- CHDI Management/CHDI Foundation, Princeton, New Jersey, United States of America
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21
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Lai TS, Greenberg CS. Histaminylation of fibrinogen by tissue transglutaminase-2 (TGM-2): potential role in modulating inflammation. Amino Acids 2014; 45:857-64. [PMID: 23797785 DOI: 10.1007/s00726-013-1532-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 06/05/2013] [Indexed: 02/03/2023]
Abstract
Plasma fibrinogen plays an important role in hemostasis and inflammation. Fibrinogen is converted to fibrin to impede blood loss and serves as the provisional matrix that aids wound healing. Fibrinogen also binds to cytokine activated endothelial cells and promotes the binding and migration of leukocytes into tissues during inflammation. Tissue transglutaminase (TGM-2) released from injured cells could cross-link fibrinogen to form multivalent complexes that could promote adhesion of platelets and vascular cells to endothelium. Histamine released by mast cells is a potent biogenic amine that promotes inflammation. The covalent attachment of histamine to proteins (histaminylation) by TGM-2 could modify local inflammatory reactions. We investigated TGM-2 crosslinking of several biogenic amines (serotonin, histamine, dopamine and noradrenaline) to fibrinogen. We identified histaminylation of fibrinogen by TGM-2 as a preferred reaction in solid and solution phase transglutaminase assays. Histamine caused a concentration-dependent inhibition of fibrinogen cross-linking by TGM-2. Fibrinogen that was not TGM-2 crosslinked bound to unactivated endothelial cells with low affinity. However, the binding was increased by sevenfold when fibrinogen was cross-linked by TGM-2. Histaminylation of fibrinogen also inhibited TGM-2 crosslinking of fibrinogen and the binding to un-activated HUVEC cells by 75–90 %. In summary, the histaminylation of fibrinogen by TGM-2 could play a role in modifying inflammation by sequestering free histamine and by inhibiting TGM-2 crosslinking of fibrinogen.
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22
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Identification of a specific one amino acid change in recombinant human transglutaminase 2 that regulates its activity and calcium sensitivity. Biochem J 2014; 455:261-72. [PMID: 23941696 DOI: 10.1042/bj20130696] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
TG2 (transglutaminase 2) is a calcium-dependent protein cross-linking enzyme which is involved in a variety of cellular processes. The threshold level of calcium needed for endogenous and recombinant TG2 activity has been controversial, the former being more sensitive to calcium than the latter. In the present study we address this question by identifying a single amino acid change from conserved valine to glycine at position 224 in recombinant TG2 compared with the endogenous sequence present in the available genomic databases. Substituting a valine residue for Gly224 in the recombinant TG2 increased its calcium-binding affinity and transamidation activity 10-fold and isopeptidase activity severalfold, explaining the inactivity of widely used recombinant TG2 at physiological calcium concentrations. ITC (isothermal titration calorimetry) measurements showed 7-fold higher calcium-binding affinities for TG2 valine residues which could be activated inside cells. The two forms had comparable substrate- and GTP-binding affinities and also bound fibronectin similarly, but coeliac antibodies had a higher affinity for TG2 valine residues. Structural analysis indicated a higher stability for TG2 valine residues and a decrease in flexibility of the calcium-binding loop resulting in improved metal-binding affinity. The results of the present study suggest that Val224 increases TG2 activity by modulating its calcium-binding affinity enabling transamidation reactions inside cells.
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23
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Kenniston JA, Conley GP, Sexton DJ, Nixon AE. A homogeneous fluorescence anisotropy assay for measuring transglutaminase 2 activity. Anal Biochem 2013; 436:13-5. [DOI: 10.1016/j.ab.2013.01.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 12/28/2012] [Accepted: 01/12/2013] [Indexed: 11/16/2022]
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24
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Russo L, Marsella C, Nardo G, Massignan T, Alessio M, Piermarini E, La Rosa S, Finzi G, Bonetto V, Bertuzzi F, Maechler P, Massa O. Transglutaminase 2 transamidation activity during first-phase insulin secretion: natural substrates in INS-1E. Acta Diabetol 2013; 50:61-72. [PMID: 22382775 DOI: 10.1007/s00592-012-0381-6] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2012] [Accepted: 02/08/2012] [Indexed: 11/28/2022]
Abstract
Transglutaminase 2 (TG2) is a multifunctional protein with Ca(2+)-dependent transamidating and G protein activity. Previously, we reported that tgm2 -/- mice have an impaired insulin secretion and that naturally occurring TG2 mutations associated with familial, early-onset type 2 diabetes, show a defective transamidating activity. Aim of this study was to get a better insight into the role of TG2 in insulin secretion by identifying substrates of TG2 transamidating activity in the pancreatic beta cell line INS-1E. To this end, we labeled INS-1E that are capable of secreting insulin upon glucose stimulation in the physiologic range, with an artificial acyl acceptor (biotinamido-pentylamine) or donor (biotinylated peptide), in basal condition and after stimulus with glucose for 2, 5, and 8 min. Biotinylated proteins were analyzed by two-dimensional electrophoresis and mass spectrometry. In addition, subcellular localization of TG2 in human endocrine pancreas was studied by electron microscopy. Among several TG2's transamidating substrates in INS-1E, mass spectrometry identified cytoplasmic actin (a result confirmed in human pancreatic islet), tropomyosin, and molecules that participate in insulin granule structure (e.g., GAPDH), glucose metabolism, or [Ca(2+)] sensing (e.g., calreticulin). Physical interaction between TG2 and cytoplasmic actin during glucose-stimulated first-phase insulin secretion was confirmed by co-immunoprecipitation. Electron microscopy revealed that TG2 is localized close to insulin and glucagon granules in human pancreatic islet. We propose that TG2's role in insulin secretion may involve cytoplasmic actin remodeling and may have a regulative action on other proteins during granule movement. A similar role of TG2 in glucagon secretion is also suggested.
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Affiliation(s)
- Lucia Russo
- Laboratory of Mendelian Diabetes, Bambino Gesù Children's Hospital, Research Institute, Rome, Italy
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25
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Wityak J, Prime ME, Brookfield FA, Courtney SM, Erfan S, Johnsen S, Johnson PD, Li M, Marston RW, Reed L, Vaidya D, Schaertl S, Pedret-Dunn A, Beconi M, Macdonald D, Muñoz-Sanjuan I, Dominguez C. SAR Development of Lysine-Based Irreversible Inhibitors of Transglutaminase 2 for Huntington's Disease. ACS Med Chem Lett 2012; 3:1024-8. [PMID: 24900424 DOI: 10.1021/ml300241m] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/04/2012] [Indexed: 11/29/2022] Open
Abstract
We report a series of irreversible transglutaminase 2 inhibitors starting from a known lysine dipeptide bearing an acrylamide warhead. We established new SARs resulting in compounds demonstrating improved potency and better physical and calculated properties. Transglutaminase selectivity profiling and in vitro ADME properties of selected compounds are also reported.
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Affiliation(s)
- John Wityak
- CHDI Management/CHDI Foundation, 6080 Center Drive, Suite 100, Los Angeles, California 90045, United States
| | - Michael E. Prime
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | | | | | - Sayeh Erfan
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Siw Johnsen
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Peter D. Johnson
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Marie Li
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | | | - Laura Reed
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Darshan Vaidya
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Sabine Schaertl
- Evotec AG, Manfred Eigen Campus, Essener Bogen 7, 22419 Hamburg, Germany
| | - Anna Pedret-Dunn
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon, OX14 4SA, United Kingdom
| | - Maria Beconi
- CHDI Management/CHDI Foundation, 6080 Center Drive, Suite 100, Los Angeles, California 90045, United States
| | - Douglas Macdonald
- CHDI Management/CHDI Foundation, 6080 Center Drive, Suite 100, Los Angeles, California 90045, United States
| | - Ignacio Muñoz-Sanjuan
- CHDI Management/CHDI Foundation, 6080 Center Drive, Suite 100, Los Angeles, California 90045, United States
| | - Celia Dominguez
- CHDI Management/CHDI Foundation, 6080 Center Drive, Suite 100, Los Angeles, California 90045, United States
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26
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Prime ME, Brookfield FA, Courtney SM, Gaines S, Marston RW, Ichihara O, Li M, Vaidya D, Williams H, Pedret-Dunn A, Reed L, Schaertl S, Toledo-Sherman L, Beconi M, Macdonald D, Muñoz-Sanjuan I, Dominguez C, Wityak J. Irreversible 4-Aminopiperidine Transglutaminase 2 Inhibitors for Huntington's Disease. ACS Med Chem Lett 2012; 3:731-5. [PMID: 24900540 DOI: 10.1021/ml3001352] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2012] [Accepted: 08/09/2012] [Indexed: 11/28/2022] Open
Abstract
A new series of potent TG2 inhibitors are reported that employ a 4-aminopiperidine core bearing an acrylamide warhead. We establish the structure-activity relationship of this new series and report on the transglutaminase selectivity and in vitro ADME properties of selected compounds. We demonstrate that the compounds do not conjugate glutathione in an in vitro setting and have superior plasma stability over our previous series.
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Affiliation(s)
- Michael E. Prime
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | | | | | - Simon Gaines
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | | | - Osamu Ichihara
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Marie Li
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Darshan Vaidya
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Helen Williams
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Anna Pedret-Dunn
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Laura Reed
- Evotec (U.K.) Ltd., 114 Milton Park, Abingdon OX14
4SA, United Kingdom
| | - Sabine Schaertl
- Evotec AG, Manfred Eigen Campus, Essener Bogen 7, 22419
Hamburg, Germany
| | - Leticia Toledo-Sherman
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
| | - Maria Beconi
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
| | - Douglas Macdonald
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
| | - Ignacio Muñoz-Sanjuan
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
| | - Celia Dominguez
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
| | - John Wityak
- CHDI Management/CHDI Foundation, 6080 Center Drive,
Suite 100, Los Angeles, California 90045, United States
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27
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Prime ME, Andersen OA, Barker JJ, Brooks MA, Cheng RKY, Toogood-Johnson I, Courtney SM, Brookfield FA, Yarnold CJ, Marston RW, Johnson PD, Johnsen SF, Palfrey JJ, Vaidya D, Erfan S, Ichihara O, Felicetti B, Palan S, Pedret-Dunn A, Schaertl S, Sternberger I, Ebneth A, Scheel A, Winkler D, Toledo-Sherman L, Beconi M, Macdonald D, Muñoz-Sanjuan I, Dominguez C, Wityak J. Discovery and structure-activity relationship of potent and selective covalent inhibitors of transglutaminase 2 for Huntington's disease. J Med Chem 2012; 55:1021-46. [PMID: 22224594 DOI: 10.1021/jm201310y] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Tissue transglutaminase 2 (TG2) is a multifunctional protein primarily known for its calcium-dependent enzymatic protein cross-linking activity via isopeptide bond formation between glutamine and lysine residues. TG2 overexpression and activity have been found to be associated with Huntington's disease (HD); specifically, TG2 is up-regulated in the brains of HD patients and in animal models of the disease. Interestingly, genetic deletion of TG2 in two different HD mouse models, R6/1 and R6/2, results in improved phenotypes including a reduction in neuronal death and prolonged survival. Starting with phenylacrylamide screening hit 7d, we describe the SAR of this series leading to potent and selective TG2 inhibitors. The suitability of the compounds as in vitro tools to elucidate the biology of TG2 was demonstrated through mode of inhibition studies, characterization of druglike properties, and inhibition profiles in a cell lysate assay.
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Abstract
Aggregated a-synuclein is the major component of inclusions in Parkinson's disease and other synucleinopathy brains indicating that a-syn aggregation is associated with the pathogenesis of neurodegenerative disorders. Although the mechanisms underlying a-syn aggregation and toxicity are not fully elucidated, it is clear that a-syn undergoes post-translational modifications and interacts with numerous proteins and other macromolecules, metals, hormones, neurotransmitters, drugs and poisons that can all modulate its aggregation propensity. The current and most recent findings regarding the factors modulating a-syn aggregation process are discussed in detail.
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29
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Nurminskaya MV, Belkin AM. Cellular functions of tissue transglutaminase. INTERNATIONAL REVIEW OF CELL AND MOLECULAR BIOLOGY 2012; 294:1-97. [PMID: 22364871 PMCID: PMC3746560 DOI: 10.1016/b978-0-12-394305-7.00001-x] [Citation(s) in RCA: 190] [Impact Index Per Article: 15.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Transglutaminase 2 (TG2 or tissue transglutaminase) is a highly complex multifunctional protein that acts as transglutaminase, GTPase/ATPase, protein disulfide isomerase, and protein kinase. Moreover, TG2 has many well-documented nonenzymatic functions that are based on its noncovalent interactions with multiple cellular proteins. A vast array of biochemical activities of TG2 accounts for its involvement in a variety of cellular processes, including adhesion, migration, growth, survival, apoptosis, differentiation, and extracellular matrix organization. In turn, the impact of TG2 on these processes implicates this protein in various physiological responses and pathological states, contributing to wound healing, inflammation, autoimmunity, neurodegeneration, vascular remodeling, tumor growth and metastasis, and tissue fibrosis. TG2 is ubiquitously expressed and is particularly abundant in endothelial cells, fibroblasts, osteoblasts, monocytes/macrophages, and smooth muscle cells. The protein is localized in multiple cellular compartments, including the nucleus, cytosol, mitochondria, endolysosomes, plasma membrane, and cell surface and extracellular matrix, where Ca(2+), nucleotides, nitric oxide, reactive oxygen species, membrane lipids, and distinct protein-protein interactions in the local microenvironment jointly regulate its activities. In this review, we discuss the complex biochemical activities and molecular interactions of TG2 in the context of diverse subcellular compartments and evaluate its wide ranging and cell type-specific biological functions and their regulation.
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Affiliation(s)
- Maria V Nurminskaya
- Department of Biochemistry and Molecular Biology, University of Maryland School of Medicine, Baltimore, Maryland, USA
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Transglutaminase 2: biology, relevance to neurodegenerative diseases and therapeutic implications. Pharmacol Ther 2011; 133:392-410. [PMID: 22212614 DOI: 10.1016/j.pharmthera.2011.12.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2011] [Accepted: 12/06/2011] [Indexed: 12/24/2022]
Abstract
Neurodegenerative disorders are characterized by progressive neuronal loss and the aggregation of disease-specific pathogenic proteins in hallmark neuropathologic lesions. Many of these proteins, including amyloid Αβ, tau, α-synuclein and huntingtin, are cross-linked by the enzymatic activity of transglutaminase 2 (TG2). Additionally, the expression and activity of TG2 is increased in affected brain regions in these disorders. These observations along with experimental evidence in cellular and mouse models suggest that TG2 can contribute to the abnormal aggregation of disease causing proteins and consequently to neuronal damage. This accumulating evidence has provided the impetus to develop inhibitors of TG2 as possible neuroprotective agents. However, TG2 has other enzymatic activities in addition to its cross-linking function and can modulate multiple cellular processes including apoptosis, autophagy, energy production, synaptic function, signal transduction and transcription regulation. These diverse properties must be taken into consideration in designing TG2 inhibitors. In this review, we discuss the biochemistry of TG2, its various physiologic functions and our current understanding about its role in degenerative diseases of the brain. We also describe the different approaches to designing TG2 inhibitors that could be developed as potential disease-modifying therapies.
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Detection of transglutaminase activity using click chemistry. Amino Acids 2011; 43:1251-63. [PMID: 22180026 PMCID: PMC3418501 DOI: 10.1007/s00726-011-1198-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 12/01/2011] [Indexed: 01/17/2023]
Abstract
Transglutaminase 2 (TG2) is a Ca2+-dependent enzyme able to catalyze the formation of ε(γ-glutamyl)-lysine crosslinks between polypeptides, resulting in high molecular mass multimers. We have developed a bioorthogonal chemical method for the labeling of TG2 glutamine-donor proteins. As amine-donor substrates we used a set of azide- and alkyne-containing primary alkylamines that allow, after being crosslinked to glutamine-donor proteins, specific labeling of these proteins via the azide-alkyne cycloaddition. We demonstrate that these azide- and alkyne-functionalized TG2 substrates are cell permeable and suitable for specific labeling of TG2 glutamine-donor substrates in HeLa and Movas cells. Both the Cu(I)-catalyzed and strain promoted azide-alkyne cycloaddition proved applicable for subsequent derivatization of the TG2 substrate proteins with the desired probe. This new method for labeling TG2 substrate proteins introduces flexibility in the detection and/or purification of crosslinked proteins, allowing differential labeling of cellular proteins.
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Király R, Demény M, Fésüs L. Protein transamidation by transglutaminase 2 in cells: a disputed Ca2+-dependent action of a multifunctional protein. FEBS J 2011; 278:4717-39. [PMID: 21902809 DOI: 10.1111/j.1742-4658.2011.08345.x] [Citation(s) in RCA: 74] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Transglutaminase 2 (TG2) is the first described cellular member of an enzyme family catalyzing Ca(2+)-dependent transamidation of proteins. During the last two decades its additional enzymatic (GTP binding and hydrolysis, protein disulfide isomerase, protein kinase) and non-enzymatic (multiple interactions in protein scaffolds) activities, which do not require Ca(2+) , have been recognized. It became a prevailing view that TG2 is silent as a transamidase, except in extreme stress conditions, in the intracellular environment characterized by low Ca(2+) and high GTP concentrations. To counter this presumption a critical review of the experimental evidence supporting the role of this enzymatic activity in cellular processes is provided. It includes the structural basis of TG2 regulation through non-canonical Ca(2+) binding sites, mechanisms making it sensitive to low Ca(2+) concentrations, techniques developed for the detection of protein transamidation in cells and examples of basic cellular phenomena as well as pathological conditions influenced by this irreversible post-translational protein modification.
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Affiliation(s)
- Róbert Király
- Department of Biochemistry and Molecular Biology, Apoptosis and Genomics Group of the Hungarian Academy of Sciences, University of Debrecen, Debrecen, Hungary
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Transglutaminase 2: a molecular Swiss army knife. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2011; 1823:406-19. [PMID: 22015769 DOI: 10.1016/j.bbamcr.2011.09.012] [Citation(s) in RCA: 189] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2011] [Revised: 09/02/2011] [Accepted: 09/06/2011] [Indexed: 12/26/2022]
Abstract
Transglutaminase 2 (TG2) is the most widely distributed member of the transglutaminase family with almost all cell types in the body expressing TG2 to varying extents. In addition to being widely expressed, TG2 is an extremely versatile protein exhibiting transamidating, protein disulphide isomerase and guanine and adenine nucleotide binding and hydrolyzing activities. TG2 can also act as a protein scaffold or linker. This unique protein also undergoes extreme conformational changes and exhibits localization diversity. Being mainly a cytosolic protein; it is also found in the nucleus, associated with the cell membrane (inner and outer side) and with the mitochondria, and also in the extracellular matrix. These different activities, conformations and localization need to be carefully considered while assessing the role of TG2 in physiological and pathological processes. For example, it is becoming evident that the role of TG2 in cell death processes is dependent upon the cell type, stimuli, subcellular localization and conformational state of the protein. In this review we discuss in depth the conformational and functional diversity of TG2 in the context of its role in numerous cellular processes. In particular, we have highlighted how differential localization, conformation and activities of TG2 may distinctly mediate cell death processes.
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TG2, a novel extracellular protein with multiple functions. Amino Acids 2011; 42:939-49. [PMID: 21818567 DOI: 10.1007/s00726-011-1008-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2011] [Accepted: 04/22/2011] [Indexed: 01/09/2023]
Abstract
TG2 is multifunctional enzyme which can be secreted to the cell surface by an unknown mechanism where its Ca(2+)-dependent transamidase activity is implicated in a number of events important to cell behaviour. However, this activity may only be transient due to the oxidation of the enzyme in the extracellular environment including its reaction with NO probably accounting for its many other roles, which are transamidation independent. In this review, we discuss the novel roles of TG2 at the cell surface and in the ECM acting either as a transamidating enzyme or as an extracellular scaffold protein involved in cell adhesion. Such roles include its ability to act as an FN co-receptor for β integrins or in a heterocomplex with FN interacting with the cell surface heparan sulphate proteoglycan syndecan-4 leading to activation of PKCα. These different properties of TG2 involve this protein in various physiological processes, which if not regulated appropriately can also lead to its involvement in a number of diseases. These include metastatic cancer, tissue fibrosis and coeliac disease, thus increasing its attractiveness as both a therapeutic target and diagnostic marker.
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Jeong KC, Ahn KO, Lee BI, Lee CH, Kim SY. The mechanism of transglutaminase 2 inhibition with glucosamine: implications of a possible anti-inflammatory effect through transglutaminase inhibition. J Cancer Res Clin Oncol 2011; 136:143-50. [PMID: 19655169 DOI: 10.1007/s00432-009-0645-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2009] [Accepted: 07/17/2009] [Indexed: 11/30/2022]
Abstract
PURPOSE Although many efforts on revealing mechanism of the constitutive activation of NF-κB in cancer cells contributed to understanding canonical pathways, largely it remains to be determined for therapeutic approaches. Recently, we found that increased expression of transglutaminase 2 (TGase 2) appears to be responsible for constitutive activation of NF-κB in certain types of cancer cells. In previous studies, we demonstrated that TGase 2 inhibition markedly increases anti-cancer drug sensitivity in drug resistance cancer cells. Therefore, we develop safe and effective TGase 2 inhibitors for therapeutic approach. METHODS We screened a chemical library of natural compounds using in vitro TGase 2 activity assay. The salient discovery was that glucosamine (GlcN), a known anti-inflammatory substance, inhibited the cross-linking activity of TGase 2. We tested, through a biochemical analysis including kinetics, whether the GlcN and GlcN analogs specifically inhibit TGase 2. We also determined the inhibitory mechanism using conformational change of TGase 2. RESULTS We found that the primary amine of GlcN plays a key role in TGase 2 inhibition. We also demonstrated that GlcN reversed TGase 2-mediated I-κBα polymerization in vitro. Interestingly, the metabolite of GlcN, glucosamine-6-phosphate (GlcN6P), inhibited TGase 2 activity via binding to the GTP-binding site with better efficiency than GlcN. In the native gel electrophoresis, it was clearly observed that GlcN6P binds to TGase 2 directly as an allosteric inhibitor. CONCLUSIONS We concluded that GlcN inhibits TGase 2 activity by direct contact. GlcN and its metabolite GlcN6P can down-regulate constitutive activation of NF-κB in vivo via inhibition of TGase 2.
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Affiliation(s)
- Kyung-Chae Jeong
- Cancer Cell and Molecular Biology Branch, Division of Cancer Biology, Research Institute, National Cancer Center, 111 Jungbalsan-ro, Ilsandong-gu, Goyang, Gyeonggi-do, 410-769, Republic of Korea
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Han BG, Cho JW, Cho YD, Jeong KC, Kim SY, Lee BI. Crystal structure of human transglutaminase 2 in complex with adenosine triphosphate. Int J Biol Macromol 2010; 47:190-5. [PMID: 20450932 DOI: 10.1016/j.ijbiomac.2010.04.023] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2010] [Revised: 04/28/2010] [Accepted: 04/28/2010] [Indexed: 12/22/2022]
Abstract
Transglutaminase 2 (TG2) is a calcium-dependent multifunctional protein associated with various human diseases. We determined the crystal structure of human TG2 in complex with adenosine triphosphate (ATP). The ATP molecule binds to the previously identified guanosine diphosphate (GDP) binding pocket but has different hydrogen bonds and ion interaction with protein. The four residues Arg476, Arg478, Val479 and Tyr583, all of which are involved in both ATP and GDP binding by hydrogen bonds, might play important roles in the stabilization of TG2 by ATP or GDP. However, Ser482 and Arg580, which are involved in GDP binding, do not form hydrogen bond with ATP. Additionally, we newly discovered an intramolecular disulfide bond between Cys230 and Cys370, which formation might regulate the enzymatic activity of TG2.
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Affiliation(s)
- Byeong-Gu Han
- Cancer Cell and Molecular Biology Branch, Division of Cancer Biology, Research Institute, National Cancer Center, Goyang, Gyeonggi 410-769, Republic of Korea
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Schaertl S, Prime M, Wityak J, Dominguez C, Munoz-Sanjuan I, Pacifici RE, Courtney S, Scheel A, Macdonald D. A profiling platform for the characterization of transglutaminase 2 (TG2) inhibitors. ACTA ACUST UNITED AC 2010; 15:478-87. [PMID: 20395409 DOI: 10.1177/1087057110366035] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Huntington's disease (HD) is associated with increased expression levels and activity of tissue transglutaminase (TG2), an enzyme primarily known for its cross-linking of proteins. To validate TG2 as a therapeutic target for HD in transgenic models and for eventual clinical development, a selective and brain-permeable inhibitor is required. Here, a comprehensive profiling platform of biochemical and cellular assays is presented which has been established to evaluate the potency, cellular efficacy, subtype selectivity and the mechanism-of-action of known and novel TG2 inhibitors. Several classes of inhibitors have been characterized including: the commonly used pseudo-substrate inhibitors, cystamine and putrescine (which are generally nonspecific for TG2 and therefore not practical for drug development), the various peptidic inhibitors that target the active site cysteine residue (which display excellent selectivity but in general have poor cellular activity), and the allosteric reversible small-molecule hydrazides (which show poor selectivity and a lack of cellular activity and could not be improved despite considerable medicinal chemistry efforts). In addition, a set of inhibitors identified from a collection of pharmacologically active compounds was found to be unselective for TG2. Moreover, inhibition at the guanosine triphosphate binding site has been examined, but apart from guanine nucleotides, no such inhibitors have been identified. In addition, the promising pharmacological profile of a TG2 inhibitor is presented which is currently in lead optimization to be developed as a tool compound.
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Lai TS, Davies C, Greenberg CS. Human tissue transglutaminase is inhibited by pharmacologic and chemical acetylation. Protein Sci 2010; 19:229-35. [PMID: 19998405 DOI: 10.1002/pro.301] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Human tissue transglutaminase (TGM2) is implicated in the pathogenesis of several neurodegenerative disorders including Alzheimer's, Parkinson's and expanded polyglutamine (polyQ) diseases. TGM2 promotes formation of soluble and insoluble high molecular weight aggregates by catalyzing a covalent linkage between peptide-bound Q residues in polyQ proteins and a peptide-bound Lys residue. Therapeutic approaches to modulate the activity of TGM2 are needed to proceed with studies to test the efficacy of TGM2 inhibition in disease processes. We investigated whether acetylation of Lys-residues by sulfosuccinimidyl acetate (SNA) or aspirin (ASA) would alter the crosslinking activity of TGM2. Acetylation by either SNA and/or ASA resulted in a loss of >90% of crosslinking activity. The Lys residues that were critical for inhibition were identified by mass spectrometry as Lys(444), Lys(468), and Lys(663). Hence, acetylation of Lys-residues may modulate the enzymatic function of TGM2 in vivo and offer a novel approach to treatment of TGM2 mediated disorders.
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Affiliation(s)
- Thung S Lai
- Department of Medicine, Medical University of South Carolina, Charleston, South Carolina 29425, USA.
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Nakano Y, Forsprecher J, Kaartinen MT. Regulation of ATPase activity of transglutaminase 2 by MT1-MMP: implications for mineralization of MC3T3-E1 osteoblast cultures. J Cell Physiol 2010; 223:260-9. [PMID: 20049897 DOI: 10.1002/jcp.22034] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A pro-mineralization function for transglutaminase 2 (TG2) has been suggested in numerous studies related to bone, cartilage, and vascular calcification. TG2 is an enzyme which can perform protein crosslinking functions, or act as a GTPase/ATPase depending upon different stimuli. We have previously demonstrated that TG2 can act as an ATPase in a Ca(2+)-rich environment and that it can regulate phosphate levels in osteoblast cultures. In this study, we investigate the role MT1-MMP in regulating the ATPase activity of TG2. We report that proteolytic cleavage of TG2 by MT1-MMP in vitro results in nearly a 3-fold increase in the ATPase activity of TG2 with a concomitant reduction in its protein-crosslinking activity. We show that MC3T3-E1 osteoblasts secreted full-length TG2 and major smaller fragments of 66 and 56 kDa, the latter having ATP-binding abilities. MT1-MMP inhibition by a neutralizing antibody suppressed mineralization of osteoblast cultures to 35% of control, and significantly reduced phosphate levels in conditioned medium (CM). Furthermore, MT1-MMP inhibition abolished two of TG2 fragments in the cultures, one of which, the 56-kDa fragment, has ATPase activity. Neutralization of MT1-MMP at early phases of mineralization significantly reduced mineral deposition, but had no effect in later phases implying MT1-MMP and TG2 might contribute to the initiation of mineralization. The cleavage of TG2 by MT1-MMP likely occurs on the cell surface/pericellular matrix where MT1-MMP and TG2 were co-localized. Based on these data, we propose that MT1-MMP modulates the extracellular function TG2 as part of a regulatory mechanism activates the pro-mineralization function of TG2.
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Affiliation(s)
- Yukiko Nakano
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University, Montreal, Quebec, Canada
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Park D, Choi SS, Ha KS. Transglutaminase 2: a multi-functional protein in multiple subcellular compartments. Amino Acids 2010; 39:619-31. [PMID: 20148342 DOI: 10.1007/s00726-010-0500-z] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 01/23/2010] [Indexed: 12/16/2022]
Abstract
Transglutaminase 2 (TG2) is a multifunctional protein that can function as a transglutaminase, G protein, kinase, protein disulfide isomerase, and as an adaptor protein. These multiple biochemical activities of TG2 account for, at least in part, its involvement in a wide variety of cellular processes encompassing differentiation, cell death, inflammation, cell migration, and wound healing. The individual biochemical activities of TG2 are regulated by several cellular factors, including calcium, nucleotides, and redox potential, which vary depending on its subcellular location. Thus, the microenvironments of the subcellular compartments to which TG2 localizes, such as the cytosol, plasma membrane, nucleus, mitochondria, or extracellular space, are important determinants to switch on or off various TG2 biochemical activities. Furthermore, TG2 interacts with a distinct subset of proteins and/or substrates depending on its subcellular location. In this review, the biological functions and molecular interactions of TG2 will be discussed in the context of the unique environments of the subcellular compartments to which TG2 localizes.
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Affiliation(s)
- Donghyun Park
- Department of Molecular and Cellular Biochemistry, Vascular System Research Center, Kangwon National University School of Medicine, Chuncheon, Kangwon-do, 200-701, Republic of Korea
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Schuppan D, Junker Y, Barisani D. Celiac disease: from pathogenesis to novel therapies. Gastroenterology 2009; 137:1912-33. [PMID: 19766641 DOI: 10.1053/j.gastro.2009.09.008] [Citation(s) in RCA: 408] [Impact Index Per Article: 27.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2009] [Revised: 09/02/2009] [Accepted: 09/11/2009] [Indexed: 02/08/2023]
Abstract
Celiac disease has become one of the best-understood HLA-linked disorders. Although it shares many immunologic features with inflammatory bowel disease, celiac disease is uniquely characterized by (1) a defined trigger (gluten proteins from wheat and related cereals), (2) the necessary presence of HLA-DQ2 or HLA-DQ8, and (3) the generation of circulating autoantibodies to the enzyme tissue transglutaminase (TG2). TG2 deamidates certain gluten peptides, increasing their affinity to HLA-DQ2 or HLA-DQ8. This generates a more vigorous CD4(+) T-helper 1 T-cell activation, which can result in intestinal mucosal inflammation, malabsorption, and numerous secondary symptoms and autoimmune diseases. Moreover, gluten elicits innate immune responses that act in concert with the adaptive immunity. Exclusion of gluten from the diet reverses many disease manifestations but is usually not or less efficient in patients with refractory celiac disease or associated autoimmune diseases. Based on the advanced understanding of the pathogenesis of celiac disease, targeted nondietary therapies have been devised, and some of these are already in phase 1 or 2 clinical trials. Examples are modified flours that have been depleted of immunogenic gluten epitopes, degradation of immunodominant gliadin peptides that resist intestinal proteases by exogenous endopeptidases, decrease of intestinal permeability by blockage of the epithelial ZOT receptor, inhibition of intestinal TG2 activity by transglutaminase inhibitors, inhibition of gluten peptide presentation by HLA-DQ2 antagonists, modulation or inhibition of proinflammatory cytokines, and induction of oral tolerance to gluten. These and other experimental therapies will be discussed critically.
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Affiliation(s)
- Detlef Schuppan
- Division of Gastroenterology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02215, USA.
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42
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Elli L, Bergamini CM, Bardella MT, Schuppan D. Transglutaminases in inflammation and fibrosis of the gastrointestinal tract and the liver. Dig Liver Dis 2009; 41:541-50. [PMID: 19195940 DOI: 10.1016/j.dld.2008.12.095] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 11/28/2008] [Accepted: 12/02/2008] [Indexed: 12/11/2022]
Abstract
Transglutaminases are a family of eight currently known calcium-dependent enzymes that catalyze the cross-linking or deamidation of proteins. They are involved in important biological processes such as wound healing, tissue repair, fibrogenesis, apoptosis, inflammation and cell-cycle control. Therefore, they play important roles in the pathomechanisms of autoimmune, inflammatory and degenerative diseases, many of which affect the gastrointestinal system. Transglutaminase 2 is prominent, since it is central to the pathogenesis of celiac disease, and modulates inflammation and fibrosis in inflammatory bowel and chronic liver diseases. This review highlights our present understanding of transglutaminase function in gastrointestinal and liver diseases and therapeutic strategies that target transglutaminase activities.
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Affiliation(s)
- L Elli
- Center for Prevention and Diagnosis of Celiac Disease, Fondazione IRCCS Ospedale Maggiore Policlinico, Mangiagalli e Regina Elena, via F. Sforza, Milan, Italy.
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Jung JE, Moon JY, Ghil SH, Yoo BS. 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) inhibits neurite outgrowth in differentiating human SH-SY5Y neuroblastoma cells. Toxicol Lett 2009; 188:153-6. [DOI: 10.1016/j.toxlet.2009.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Revised: 03/30/2009] [Accepted: 04/02/2009] [Indexed: 10/20/2022]
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Pardin C, Roy I, Chica RA, Bonneil E, Thibault P, Lubell WD, Pelletier JN, Keillor JW. Photolabeling of tissue transglutaminase reveals the binding mode of potent cinnamoyl inhibitors. Biochemistry 2009; 48:3346-53. [PMID: 19271761 DOI: 10.1021/bi802021c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have recently developed a new class of cinnamoyl derivatives as potent tissue transglutaminase (TG2) inhibitors. Herein, we report the synthesis of a diazirine derivative of these inhibitors and its application to the photolabeling of its binding site on guinea pig liver transglutaminase. Two novel homology models were generated for this commonly studied TG2, which differ in the conformational state they represent. Tryptic digest and mass spectrometric analysis of the photolabeling experiment showed that only residue Cys230 was labeled, and our homology models were used to visualize these results. This visualization suggested that Cys230 is somewhat more solvent-exposed in the "closed" conformation of TG2, compared to the "open" conformation. Docking experiments suggested binding modes consistent with the labeling pattern that would block access to the tunnel leading to the active site, consistent with the observed mode of inhibition. However, while these modeling simulations favored the closed conformation as the target of our cinnamoyl inhibitors, native PAGE experiments indicated the open conformation of the enzyme in fact predominates in the presence of our photolabeling derivative. These results are important for understanding the binding modes of TG2 inhibitors in general and will be critical for the structure-based design of future inhibitors.
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45
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Jeong EM, Kim CW, Cho SY, Jang GY, Shin DM, Jeon JH, Kim IG. Degradation of transglutaminase 2 by calcium-mediated ubiquitination responding to high oxidative stress. FEBS Lett 2009; 583:648-54. [PMID: 19183553 DOI: 10.1016/j.febslet.2009.01.032] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2008] [Revised: 01/07/2009] [Accepted: 01/19/2009] [Indexed: 11/17/2022]
Abstract
Transglutaminase 2 (TG2) is a calcium-dependent enzyme that catalyzes the transamidation reaction. There is conflicting evidence on the role of TG2 in apoptosis. In this report, we show that TG2 increases in response to low level of oxidative stress, whereas TG2 diminishes under high stress conditions. Monitoring TG2 expression, activity and calcium concentration in cells treated with A23187 revealed that the initial rise of calcium activates TG2 but subsequent calcium-overload induces the degradation of TG2 via calcium-mediated polyubiquitination. These results indicate that the role of TG2 in apoptosis depends on the level of calcium influx triggered by oxidative stress.
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Affiliation(s)
- Eui Man Jeong
- Department of Biochemistry and Molecular Biology/Aging and Apoptosis Research Center (AARC), Seoul National University College of Medicine, 28 Yongon Dong, Chongno Gu, Seoul 110-799, Republic of Korea
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46
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Lai TS, Liu Y, Tucker T, Daniel KR, Sane DC, Toone E, Burke JR, Strittmatter WJ, Greenberg CS. Identification of chemical inhibitors to human tissue transglutaminase by screening existing drug libraries. ACTA ACUST UNITED AC 2008; 15:969-78. [PMID: 18804034 DOI: 10.1016/j.chembiol.2008.07.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2007] [Revised: 07/16/2008] [Accepted: 07/23/2008] [Indexed: 12/20/2022]
Abstract
Human tissue transglutaminase (TGM2) is a calcium-dependent crosslinking enzyme involved in the posttranslational modification of intra- and extracellular proteins and implicated in several neurodegenerative diseases. To find specific inhibitors to TGM2, two structurally diverse chemical libraries (LOPAC and Prestwick) were screened. We found that ZM39923, a Janus kinase inhibitor, and its metabolite ZM449829 were the most potent inhibitors with IC(50) of 10 and 5 nM, respectively. In addition, two other inhibitors, including tyrphostin 47 and vitamin K(3), were found to have an IC(50) in the micromolar range. These agents used in part a thiol-dependent mechanism to inhibit TGM2, consistent with the activation of TGM2 by reduction of an intramolecular disulfide bond. These inhibitors were tested in a polyglutamine-expressing Drosophila model of neurodegeneration and found to improve survival. The TGM2 inhibitors we discovered may serve as valuable lead compounds for the development of orally active TGM2 inhibitors to treat human diseases.
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Affiliation(s)
- Thung-S Lai
- Department of Medicine, Duke University Medical Center, Durham, NC 27710, USA.
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47
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Mehta K. Biological and therapeutic significance of tissue transglutaminase in pancreatic cancer. Amino Acids 2008; 36:709-16. [PMID: 18594944 DOI: 10.1007/s00726-008-0128-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2008] [Accepted: 05/10/2008] [Indexed: 12/18/2022]
Abstract
Pancreatic ductal adenocarcinoma (PDA) is one of the deadliest cancers world-wide with an estimated annual incidence and mortality rates of approximately 6,500 cases in the UK, over 40,000 cases in Europe, 19,000 cases in Japan and over 30,000 cases in the United States. Difficulty to diagnose the disease at an early stage, rapid progression and intrinsic resistance to currently available therapies are major factors that contribute to poor disease outcome in these patients (overall 5 years survival, <3%). Identification of cancer cell-encoded genes that contribute to the development of intrinsic resistance and metastatic spread of the PDA tumors, may yield immediate clinical benefits in terms of revealing new therapeutic targets for effective treatment of the disease. This article discusses the significance of tissue-type transglutaminase (TG2) whose expression is elevated in the majority of PDA tumors and cell lines. Based on the published data and the results discussed in this review, TG2 appears to be a promising target for containment and treatment of this formidable disease.
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Affiliation(s)
- K Mehta
- Department of Experimental Therapeutics, The University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Blvd., Unit 362, Houston, TX 77030, USA.
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48
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Wilhelmus MMM, van Dam AM, Drukarch B. Tissue transglutaminase: a novel pharmacological target in preventing toxic protein aggregation in neurodegenerative diseases. Eur J Pharmacol 2008; 585:464-72. [PMID: 18417122 DOI: 10.1016/j.ejphar.2008.01.059] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 01/10/2008] [Accepted: 01/24/2008] [Indexed: 11/30/2022]
Abstract
Alzheimer's disease, Parkinson's disease and Huntington's disease are neurodegenerative diseases, characterized by the accumulation and deposition of neurotoxic protein aggregates. The capacity of specific proteins to self-interact and form neurotoxic aggregates seems to be a common underlying mechanism leading to pathology in these neurodegenerative diseases. This process might be initiated and/or accelerated by proteins that interact with these aggregating proteins. The transglutaminase (TG) family of proteins are calcium-dependent enzymes that catalyze the formation of covalent epsilon-(gamma-glutamyl)lysine isopeptide bonds, which can result in both intra- and intermolecular cross-links. Intramolecular cross-links might modify self-interacting proteins, and make them more prone to aggregate. In addition, intermolecular cross-links could link self-aggregating proteins and thereby initiate and/or stimulate the aggregation process. So far, increased levels and activity of tissue transglutaminase (tTG), the best characterized member of the TG family, have been observed in many neurodegenerative diseases, and the self-interacting proteins, characteristic of Alzheimer's disease, Parkinson's disease and Huntington's disease, are known substrates of tTG. Here, we focus on the role of tTG in the initiation of the aggregation process of self-interacting proteins in these diseases, and promote the notion that tTG might be an attractive novel target for treatment of neurodegenerative diseases.
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Affiliation(s)
- Micha M M Wilhelmus
- Department of Anatomy and Neurosciences VU University Medical Center, Institute for Clinical and Experimental Neurosciences (ICEN), Amsterdam, The Netherlands.
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49
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Datta S, Antonyak MA, Cerione RA. GTP-binding-defective forms of tissue transglutaminase trigger cell death. Biochemistry 2007; 46:14819-29. [PMID: 18052077 PMCID: PMC2527651 DOI: 10.1021/bi701422h] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Tissue transglutaminase (TGase-2), which binds GTP and catalyzes the cross-linking of proteins (transamidation), has been implicated both in the promotion of cell death and in the protection of cells against apoptotic insults. However, a novel transcript originally identified from the brains of Alzheimer's patients, encoding a truncated form of TGase-2 (called TGase-S), shows strong apoptotic activity. TGase-S exhibits no detectable GTP-binding capability, suggesting that its ability to induce cell death might be due to its inability to bind GTP. Thus, we have examined whether eliminating the GTP-binding capability of full-length human TGase-2 would prevent it from conferring protection against apoptotic challenges and instead convert it into a protein that causes cell death. A number of point mutants of human TGase-2 defective for binding GTP, as well as a mutant that shows impaired GTP-hydrolytic activity, were generated. Similar to what we had found for TGase-S, there was a time-dependent decrease in the expression of the GTP-binding-defective TGase-2 mutants in different cell lines, whereas the expression of wild-type TGase-2 and the GTP hydrolysis-defective mutant was sustained. Moreover, the GTP-binding-defective TGase-2 mutants induced cell death. The cell death responses triggered by these mutants were not due to their transdamidation activity, because double-mutants that were both GTP-binding- and transamidation-defective also stimulated cell death. Therefore, these results point to the inability to bind GTP as being sufficient for the apoptotic activity exhibited by the TGase-S protein. They also highlight a novel example of how the loss of GTP-binding activity can convert a protein that provides protection against apoptotic stimuli into a cell death-promoting factor.
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Affiliation(s)
- Sunando Datta
- Department of Chemistry and Chemical Biology, Baker Laboratory
| | - Marc A. Antonyak
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853
| | - Richard A. Cerione
- Department of Chemistry and Chemical Biology, Baker Laboratory
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University, Ithaca, NY 14853
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50
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Nakano Y, Addison WN, Kaartinen MT. ATP-mediated mineralization of MC3T3-E1 osteoblast cultures. Bone 2007; 41:549-61. [PMID: 17669706 DOI: 10.1016/j.bone.2007.06.011] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2007] [Revised: 04/24/2007] [Accepted: 06/15/2007] [Indexed: 01/10/2023]
Abstract
While bone is hypomineralized in hypophosphatemia patients and in tissue-nonspecific alkaline phosphatase (Tnsalp)-deficient mice, the extensive mineralization that nevertheless occurs suggests involvement of other phosphatases in providing phosphate ions for mineral deposition. Although the source of phosphate liberated by these phosphatases is unknown, pyrophosphate, ATP, pyridoxal-5'-phosphate (PLP) and phoshoethanolamine (PEA) are likely candidates. In this study, we have induced mineralization of MC3T3-E1 osteoblast cultures using ATP, and have investigated potential phosphatases involved in this mineralization process. MC3T3-E1 osteoblasts were cultured for 12 days and treated either with beta-glycerophosphate (betaGP) or ATP. Matrix and mineral deposition was examined by biochemical, cytochemical, ultrastructural and X-ray microanalytical methods. ATP added at levels of 4-5 mM resulted in mineral deposition similar to that following conventional treatment with betaGP. Collagen levels were similarly normal in ATP-mineralized cultures and transmission electron microscopy and X-ray microanalysis confirmed hydroxyapatite mineral deposition along the collagen fibrils in the ECM. Phosphate release from 4 mM ATP into the medium was rapid and resulted in approximately twice the phosphate levels than after release from 10 mM betaGP. ATP treatment did not affect mineralization by altering the expression of mineral-regulating genes such as Enpp1, Ank, and Mgp, nor phosphatase genes indicating that ATP induces mineralization by serving as a phosphate source for mineral deposition. Levamisole, an inhibitor of TNSALP, completely blocked mineralization in betaGP-treated cultures, but had minor effects on ATP-mediated mineralization, indicating that other phosphatases such as plasma membrane Ca2+ transport ATPase 1 (PMCA1) and transglutaminase 2 (TG2) are contributing to ATP hydrolysis. To examine their involvement in ATP-mediated mineralization, the inhibitors cystamine (TG2 inhibitor) and ortho-vanadate (PMCA inhibitor) were added to the cultures - both inhibitors significantly reduced mineralization whereas suppression of the phosphate release by ortho-vanadate was minor comparing to other two inhibitors. The contribution of PMCA1 to mineralization may occur through pumping of calcium towards calcification sites and TG2 can likely act as an ATPase in the ECM. Unlike the GTPase activity of TG2, its ATPase function was resistant to calcium, demonstrating the potential for participation in ATP hydrolysis and mineral deposition within the ECM at elevated calcium concentrations.
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Affiliation(s)
- Yukiko Nakano
- Division of Biomedical Sciences, Faculty of Dentistry, McGill University, Montreal, QC, Canada.
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