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Tomkinson B. Tripeptidyl-peptidase II: Update on an oldie that still counts. Biochimie 2019; 166:27-37. [DOI: 10.1016/j.biochi.2019.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2019] [Accepted: 05/14/2019] [Indexed: 12/30/2022]
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2
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Nahálková J. The protein-interaction network with functional roles in tumorigenesis, neurodegeneration, and aging. Mol Cell Biochem 2016; 423:187-196. [DOI: 10.1007/s11010-016-2836-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2016] [Accepted: 09/23/2016] [Indexed: 01/13/2023]
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Wiemhoefer A, Stargardt A, van der Linden WA, Renner MC, van Kesteren RE, Stap J, Raspe MA, Tomkinson B, Kessels HW, Ovaa H, Overkleeft HS, Florea B, Reits EA. Tripeptidyl Peptidase II Mediates Levels of Nuclear Phosphorylated ERK1 and ERK2. Mol Cell Proteomics 2015; 14:2177-93. [PMID: 26041847 DOI: 10.1074/mcp.m114.043331] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2014] [Indexed: 12/22/2022] Open
Abstract
Tripeptidyl peptidase II (TPP2) is a serine peptidase involved in various biological processes, including antigen processing, cell growth, DNA repair, and neuropeptide mediated signaling. The underlying mechanisms of how a peptidase can influence this multitude of processes still remain unknown. We identified rapid proteomic changes in neuroblastoma cells following selective TPP2 inhibition using the known reversible inhibitor butabindide, as well as a new, more potent, and irreversible peptide phosphonate inhibitor. Our data show that TPP2 inhibition indirectly but rapidly decreases the levels of active, di-phosphorylated extracellular signal-regulated kinase 1 (ERK1) and ERK2 in the nucleus, thereby down-regulating signal transduction downstream of growth factors and mitogenic stimuli. We conclude that TPP2 mediates many important cellular functions by controlling ERK1 and ERK2 phosphorylation. For instance, we show that TPP2 inhibition of neurons in the hippocampus leads to an excessive strengthening of synapses, indicating that TPP2 activity is crucial for normal brain function.
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Affiliation(s)
- Anne Wiemhoefer
- From the ‡Department of Cell Biology and Histology, Academic Medical Centre- University of Amsterdam, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
| | - Anita Stargardt
- From the ‡Department of Cell Biology and Histology, Academic Medical Centre- University of Amsterdam, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
| | - Wouter A van der Linden
- §Department of Pathology, Stanford School of Medicine, 300 Pasteur Drive, Stanford, CA 94305-5324
| | - Maria C Renner
- ¶Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA Amsterdam, The Netherlands
| | - Ronald E van Kesteren
- ‖Center for Neurogenomics and Cognitive Research, VU University Amsterdam, De Boelelaan 1085, 1081HV Amsterdam, The Netherlands
| | - Jan Stap
- From the ‡Department of Cell Biology and Histology, Academic Medical Centre- University of Amsterdam, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands
| | - Marcel A Raspe
- **Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - Birgitta Tomkinson
- ‡‡Department of Medical Biochemistry and Microbiology, University of Uppsala, Husargatan 3, 75123 Uppsala, Sweden
| | - Helmut W Kessels
- ¶Netherlands Institute for Neuroscience, Meibergdreef 47, 1105BA Amsterdam, The Netherlands
| | - Huib Ovaa
- **Division of Cell Biology, The Netherlands Cancer Institute, Plesmanlaan 121, 1066CX Amsterdam, The Netherlands
| | - Herman S Overkleeft
- §§Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
| | - Bogdan Florea
- §§Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2333CC Leiden, The Netherlands
| | - Eric A Reits
- From the ‡Department of Cell Biology and Histology, Academic Medical Centre- University of Amsterdam, Meibergdreef 15, 1105AZ Amsterdam, The Netherlands;
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Wang ZH, Liu XL, Zhong M, Zhang LP, Shang YY, Hu XY, Li L, Zhang Y, Deng JT, Zhang W. Pleiotropic Effects of Atorvastatin on Monocytes in Atherosclerotic Patients. J Clin Pharmacol 2013; 50:311-9. [DOI: 10.1177/0091270009340889] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Usukura K, Kasamatsu A, Okamoto A, Kouzu Y, Higo M, Koike H, Sakamoto Y, Ogawara K, Shiiba M, Tanzawa H, Uzawa K. Tripeptidyl peptidase II in human oral squamous cell carcinoma. J Cancer Res Clin Oncol 2012; 139:123-30. [PMID: 22986808 DOI: 10.1007/s00432-012-1307-y] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2012] [Accepted: 09/03/2012] [Indexed: 01/08/2023]
Abstract
PURPOSE Tripeptidyl peptidase II (TPP2), a member of the family of eukaryotic serine peptidase, has been implicated in DNA repair, cellular division, and apoptosis. The aim of this study was to examine TPP2 expression and its functional mechanisms in oral squamous cell carcinoma (OSCC). METHODS TPP2 mRNA and protein expression in seven OSCC-derived cells (Ca9-22, HSC-2, HSC-3, HSC-4, HO-1-N-1, H1, and Sa3) was analyzed by quantitative reverse transcriptase-polymerase chain reaction and immunoblotting analyses. Since previous studies indicated that TPP2 might control chromosomal division, we investigated cellular proliferation and spindle assembly checkpoint (SAC) molecules, MAD2 and CCNB1. In addition, we evaluated the correlation between TPP2 expression levels in primary OSCCs (n = 108 specimens) and the clinicopathologic status by immunohistochemistry (IHC). RESULTS TPP2 mRNA and protein were significantly (P < 0.05) up-regulated in OSCC-derived cells compared with human normal oral keratinocytes. Suppression of TPP2 expression with shRNA significantly (P < 0.05) inhibited cellular proliferation compared with the control cells. In addition, appropriate localization of MAD2 and up-regulation of CCNB1 were observed in TPP2 knockdown OSCC cells. IHC showed that TPP2 expression in primary OSCCs was significantly (P < 0.001) greater than that in the normal oral counterparts, and the TPP2-positive cases were significantly (P < 0.05) correlated with tumor size. CONCLUSION The current study showed that overexpression of TPP2 occurs frequently during oral carcinogenesis and might be associated with OSCC progression via SAC activation.
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Affiliation(s)
- Katsuya Usukura
- Department of Clinical Molecular Biology, Graduate School of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
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Eklund S, Lindås AC, Hamnevik E, Widersten M, Tomkinson B. Exploring the active site of tripeptidyl-peptidase II through studies of pH dependence of reaction kinetics. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2012; 1824:561-70. [DOI: 10.1016/j.bbapap.2012.01.004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2011] [Revised: 01/03/2012] [Accepted: 01/03/2012] [Indexed: 11/16/2022]
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7
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Rockel B, Kopec KO, Lupas AN, Baumeister W. Structure and function of tripeptidyl peptidase II, a giant cytosolic protease. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2011; 1824:237-45. [PMID: 21771670 DOI: 10.1016/j.bbapap.2011.07.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Revised: 06/29/2011] [Accepted: 07/01/2011] [Indexed: 01/25/2023]
Abstract
Tripeptidyl peptidase II is the largest known eukaryotic peptidase. It has been described as a multi-purpose peptidase, which, in addition to its house-keeping function in intracellular protein degradation, plays a role in several vital cellular processes such as antigen processing, apoptosis, or cell division, and is involved in diseases like muscle wasting, obesity, and in cancer. Biochemical studies and bioinformatics have identified TPPII as a subtilase, but its structure is very unusual: it forms a large homooligomeric complex (6 MDa) with a spindle-like shape. Recently, the high-resolution structure of TPPII homodimers (300 kDa) was solved and a hybrid structure of the holocomplex built of 20 dimers was obtained by docking it into the EM-density. Here, we summarize our current knowledge about TPPII with a focus on structural aspects. This article is part of a Special Issue entitled: Proteolysis 50 years after the discovery of lysosome.
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Affiliation(s)
- Beate Rockel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, Martinsried, Germany.
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8
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van Endert P. Post-proteasomal and proteasome-independent generation of MHC class I ligands. Cell Mol Life Sci 2011; 68:1553-67. [PMID: 21390545 PMCID: PMC11115176 DOI: 10.1007/s00018-011-0662-1] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2011] [Revised: 02/17/2011] [Accepted: 02/18/2011] [Indexed: 12/18/2022]
Abstract
Peptide ligands presented by MHC class I molecules are produced by intracellular proteolysis, which often involves multiple steps. Initial antigen degradation seems to rely almost invariably on the proteasome, although tripeptidyl peptidase II (TPP II) and insulin-degrading enzyme (IDE) may be able to substitute for the proteasome in rare cases. Recent evidence suggests that the net effect of cytosolic aminopeptidases is destruction of potential class I ligands, although a positive role in selected cases has been documented. This may apply particularly to the trimming of long precursors by TPP II. In contrast, trimming of ligand precursors in the endoplasmic reticulum is essential for the generation of suitable peptides and has a substantial impact on the repertoire of ligands presented. Trimming by the ER aminopeptidase (ERAP) enzymes most likely acts on free precursors and is adapted to the needs of class I molecules by way of a molecular ruler mechanism. Trimming by ERAP enzymes also occurs for cross-presented ligands, which can alternatively be processed in a special endosomal compartment by insulin-regulated aminopeptidase.
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Affiliation(s)
- Peter van Endert
- Institut National de la Santé et de la Recherche Médicale, Unité 1013, Paris 75015, France.
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The Enigma of Tripeptidyl-Peptidase II: Dual Roles in Housekeeping and Stress. JOURNAL OF ONCOLOGY 2010; 2010. [PMID: 20847939 PMCID: PMC2933905 DOI: 10.1155/2010/128478] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2009] [Revised: 05/25/2010] [Accepted: 07/12/2010] [Indexed: 12/02/2022]
Abstract
The tripeptidyl-peptidase II complex consists of repeated 138 kDa subunits, assembled into two twisted strands that form a high molecular weight complex (>5 MDa). TPPII, like many other cytosolic peptidases, plays a role in the ubiquitin-proteasome pathway downstream of the proteasome as well as in the production and destruction of MHC class I antigens and degradation of neuropeptides. Tripeptidyl-peptidase II activity is increased in cells with an increased demand for protein degradation, but whether degradation of cytosolic peptides is the only cell biological role for TPPII has remained unclear. Recent data indicated that TPPII translocates into the nucleus to control DNA damage responses in malignant cells, supporting that cytosolic “housekeeping peptidases” may have additional roles in cell biology, besides their contribution to protein turnover. Overall, TPPII has an emerging importance in several cancer-related fields, such as metabolism, cell death control, and control of genome integrity; roles that are not understood in detail. The present paper reviews the cell biology of TPPII and discusses distinct roles for TPPII in the nucleus and cytosol.
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10
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Chuang CK, Rockel B, Seyit G, Walian PJ, Schönegge A, Peters J, Zwart PH, Baumeister W, Jap BK. Hybrid molecular structure of the giant protease tripeptidyl peptidase II. Nat Struct Mol Biol 2010; 17:990-6. [PMID: 20676100 PMCID: PMC2939011 DOI: 10.1038/nsmb.1870] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2010] [Accepted: 05/28/2010] [Indexed: 01/07/2023]
Abstract
Tripeptidyl peptidase II (TPP II) is the largest known eukaryotic protease (6 MDa). It is believed to act downstream of the 26S proteasome, cleaving tripeptides from the N termini of longer peptides, and it is implicated in numerous cellular processes. Here we report the structure of Drosophila TPP II determined by a hybrid approach. We solved the structure of the dimer by X-ray crystallography and docked it into the three-dimensional map of the holocomplex, which we obtained by single-particle cryo-electron microscopy. The resulting structure reveals the compartmentalization of the active sites inside a system of chambers and suggests the existence of a molecular ruler determining the size of the cleavage products. Furthermore, the structure suggests a model for activation of TPP II involving the relocation of a flexible loop and a repositioning of the active-site serine, coupling it to holocomplex assembly and active-site sequestration.
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Affiliation(s)
- Crystal K. Chuang
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA, Graduate Group in Comparative Biochemistry, University of California, Berkeley, California 94720, USA
| | - Beate Rockel
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, D–82152 Martinsried, Germany
| | - Gönül Seyit
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, D–82152 Martinsried, Germany
| | - Peter J. Walian
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA
| | - Anne–Marie Schönegge
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, D–82152 Martinsried, Germany
| | - Jürgen Peters
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, D–82152 Martinsried, Germany
| | - Petrus H. Zwart
- Advanced Light Source, Lawrence Berkeley National Laboratory
| | - Wolfgang Baumeister
- Department of Molecular Structural Biology, Max Planck Institute of Biochemistry, D–82152 Martinsried, Germany,To whom correspondence should be addressed., ;
| | - Bing K. Jap
- Life Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA, Graduate Group in Comparative Biochemistry, University of California, Berkeley, California 94720, USA,To whom correspondence should be addressed., ;
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Villasevil EM, Guil S, López-Ferreras L, Sánchez C, Del Val M, Antón LC. Accumulation of polyubiquitylated proteins in response to Ala-Ala-Phe-chloromethylketone is independent of the inhibition of Tripeptidyl peptidase II. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2010; 1803:1094-105. [PMID: 20553980 DOI: 10.1016/j.bbamcr.2010.06.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/31/2010] [Accepted: 06/01/2010] [Indexed: 11/26/2022]
Abstract
In the present study we have addressed the issue of proteasome independent cytosolic protein degradation. Tripeptidyl peptidase II (TPPII) has been suggested to compensate for a reduced proteasome activity, partly based on evidence using the inhibitor Ala-Ala-Phe-chloromethylketone (AAF-cmk). Here we show that AAF-cmk induces the formation of polyubiquitin-containing accumulations in osteosarcoma and Burkitt's lymphoma cell lines. These accumulations meet many of the landmarks of the aggresomes that form after proteasome inhibition. Using a combination of experiments with chemical inhibitors and interference of gene expression, we show that TPPII inhibition is not responsible for these accumulations. Our evidence suggests that the relevant target(s) is/are in the ubiquitin-proteasome pathway, most likely upstream the proteasome. We obtained evidence supporting this model by inhibition of Hsp90, which also acts upstream the proteasome. Although our data suggest that Hsp90 is not a target of AAF-cmk, its inhibition resulted in accumulations similar to those obtained with AAF-cmk. Therefore, our results question the proposed role for TPPII as a prominent alternative to the proteasome in cellular proteolysis.
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Affiliation(s)
- Eugenia M Villasevil
- Centro de Biología Molecular Severo Ochoa, Consejo Superior de Investigaciones Científicas/Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain
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Tsurumi C, Firat E, Gaedicke S, Huai J, Mandal PK, Niedermann G. Viability and DNA damage responses of TPPII-deficient Myc- and Ras-transformed fibroblasts. Biochem Biophys Res Commun 2009; 386:563-8. [DOI: 10.1016/j.bbrc.2009.06.068] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 06/10/2009] [Indexed: 11/30/2022]
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13
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Firat E, Tsurumi C, Gaedicke S, Huai J, Niedermann G. Tripeptidyl Peptidase II Plays a Role in the Radiation Response of Selected Primary Cell Types but not Based on Nuclear Translocation and p53 Stabilization. Cancer Res 2009; 69:3325-31. [DOI: 10.1158/0008-5472.can-08-3269] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Eriksson S, Gutiérrez OA, Bjerling P, Tomkinson B. Development, evaluation and application of tripeptidyl-peptidase II sequence signatures. Arch Biochem Biophys 2009; 484:39-45. [PMID: 19467630 DOI: 10.1016/j.abb.2009.01.007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2008] [Accepted: 01/07/2009] [Indexed: 11/24/2022]
Abstract
Tripeptidyl-peptidase II (TPP II) is a cytosolic peptidase that has been implicated in fat formation and cancer, apparently independent of the enzymatic activity. In search for alternative functional regions, conserved motifs were identified and eleven signatures were constructed. Seven of the signatures covered previously investigated residues, whereas the functional importance of the other motifs is unknown. This provides directions for future investigations of alternative activities of TPP II. The obtained signatures provide an efficient bioinformatic tool for the identification of TPP II homologues. Hence, a TPP II sequence homologue from fission yeast, Schizosaccharomyces pombe, was identified and demonstrated to encode the TPP II-like protein previously reported as multicorn. Furthermore, an homologous protein was found in the prokaryote Blastopirellula marina, albeit the TPP II function was apparently not conserved. This gene is probably the result of a rare gene transfer from eukaryote to prokaryote.
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Affiliation(s)
- Sandra Eriksson
- Department of Biochemistry and Organic Chemistry, Uppsala University, Uppsala, Sweden
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15
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Sompallae R, Stavropoulou V, Houde M, Masucci MG. The MAPK signaling cascade is a central hub in the regulation of cell cycle, apoptosis and cytoskeleton remodeling by tripeptidyl-peptidase II. GENE REGULATION AND SYSTEMS BIOLOGY 2008; 2:253-65. [PMID: 19787088 PMCID: PMC2733081 DOI: 10.4137/grsb.s882] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Tripeptidyl-peptidase II (TPPII) is a serine peptidase highly expressed in malignant Burkitt's lymphoma cells (BL). We have previously shown that overexpression of TPPII correlates with chromosomal instability, centrosomal and mitotic spindle abnormalities and resistance to apoptosis induced by spindle poisons. Furthermore, TPPII knockdown by RNAi was associated with endoreplication and the accumulation of polynucleated cells that failed to complete cell division, indicating a role of TPPII in the cell cycle. Here we have applied a global approach of gene expression analysis to gain insights on the mechanism by which TPPII regulates this phenotype. mRNA profiling of control and TPPII knockdown BL cells identified one hundred and eighty five differentially expressed genes. Functional categorization of these genes highlighted major physiological functions such as apoptosis, cell cycle progression, cytoskeleton remodeling, proteolysis, and signal transduction. Pathways and protein interactome analysis revealed a significant enrichment in components of MAP kinases signaling. These findings suggest that TPPII influences a wide network of signaling pathways that are regulated by MAPKs and exerts thereby a pleiotropic effect on biological processes associated with cell survival, proliferation and genomic instability.
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Preta G, Marescotti D, Fortini C, Carcoforo P, Castelli C, Masucci M, Gavioli R. Inhibition of serine-peptidase activity enhances the generation of a survivin-derived HLA-A2-presented CTL epitope in colon-carcinoma cells. Scand J Immunol 2008; 68:579-88. [PMID: 19000094 DOI: 10.1111/j.1365-3083.2008.02175.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Cytotoxic T lymphocytes eliminate tumor cells expressing antigenic peptides in the context of MHC-I molecules. Peptides are generated during protein degradation by the proteasome and resulting products, surviving cytosolic amino-peptidases activity, may be presented by MHC-I molecules. The MHC-I processing pathway is altered in a large number of malignancies and modulation of antigen generation is one strategy employed by cells to evade immune control. In this study we analyzed the generation and presentation of a survivin-derived CTL epitope in HLA-A2-positive colon-carcinoma cells. Although all cell lines expressed the anti-apoptotic protein survivin, some tumors were poorly recognized by ELTLGEFLKL (ELT)-specific CTL cultures. The expression of MHC-I or TAP molecules was similar in all cell lines suggesting that tumors not recognized by CTLs may present defects in the generation of the ELT-epitope which could be due either to lack of generation or to subsequent degradation of the epitope. The cells were analyzed for the expression and the activity of extra-proteasomal peptidases. A significant overexpression and higher activity of TPPII was observed in colon-carcinoma cells which are not killed by ELT-specific CTLs, suggesting a possible role of TPPII in the degradation of the ELT-epitope. To confirm the role of TPPII in the degradation of the ELT-peptide, we showed that treatment of colon-carcinoma cells with a TPPII inhibitor resulted in a dose-dependent increased sensitivity to ELT-specific CTLs. These results suggest that TPPII is involved in degradation of the ELT-peptide, and its overexpression may contribute to the immune escape of colon-carcinoma cells.
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Affiliation(s)
- G Preta
- Department of Biochemistry and Molecular Biology, University of Ferrara, Ferrara, Italy
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Activation of cellular death programs associated with immunosenescence-like phenotype in TPPII knockout mice. Proc Natl Acad Sci U S A 2008; 105:5177-82. [PMID: 18362329 DOI: 10.1073/pnas.0801413105] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The giant cytosolic protease tripeptidyl peptidase II (TPPII) has been implicated in the regulation of proliferation and survival of malignant cells, particularly lymphoma cells. To address its functions in normal cellular and systemic physiology we have generated TPPII-deficient mice. TPPII deficiency activates cell type-specific death programs, including proliferative apoptosis in several T lineage subsets and premature cellular senescence in fibroblasts and CD8(+) T cells. This coincides with up-regulation of p53 and dysregulation of NF-kappaB. Prominent degenerative alterations at the organismic level were a decreased lifespan and symptoms characteristic of immunohematopoietic senescence. These symptoms include accelerated thymic involution, lymphopenia, impaired proliferative T cell responses, extramedullary hematopoiesis, and inflammation. Thus, TPPII is important for maintaining normal cellular and systemic physiology, which may be relevant for potential therapeutic applications of TPPII inhibitors.
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Molecular pathogenesis of Shigella spp.: controlling host cell signaling, invasion, and death by type III secretion. Clin Microbiol Rev 2008; 21:134-56. [PMID: 18202440 DOI: 10.1128/cmr.00032-07] [Citation(s) in RCA: 398] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Shigella spp. are gram-negative pathogenic bacteria that evolved from harmless enterobacterial relatives and may cause devastating diarrhea upon ingestion. Research performed over the last 25 years revealed that a type III secretion system (T3SS) encoded on a large plasmid is a key virulence factor of Shigella flexneri. The T3SS determines the interactions of S. flexneri with intestinal cells by consecutively translocating two sets of effector proteins into the target cells. Thus, S. flexneri controls invasion into EC, intra- and intercellular spread, macrophage cell death, as well as host inflammatory responses. Some of the translocated effector proteins show novel biochemical activities by which they intercept host cell signal transduction pathways. An understanding of the molecular mechanisms underlying Shigella pathogenesis will foster the development of a safe and efficient vaccine, which, in parallel with improved hygiene, should curb infections by this widespread pathogen.
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Rockel B, Baumeister W. A tale of two giant proteases. ERNST SCHERING FOUNDATION SYMPOSIUM PROCEEDINGS 2008:17-40. [PMID: 19198062 DOI: 10.1007/2789_2008_099] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The 26S proteasome and tripeptidyl peptidase II (TPPII) are two exceptionally large eukaryotic protein complexes involved in intracellular proteolysis, where they exert their function sequentially: the proteasome, a multisubunit complex of 2.5 MDa, acts at the downstream end of the ubiquitin pathway and degrades ubiquitinylated proteins into small oligopeptides. Such oligopeptides are substrates for TPPII, a 6-MDa homooligomer, which releases tripeptides from their free N-terminus. Both 26S and TPPII are very fragile complexes refractory to crystallization and in their fully assembled native form have been visualized only by electron microscopy. Here, we will discuss the structural features of the two complexes and their functional implications.
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Affiliation(s)
- B Rockel
- Department of Molecular Structural Biology, Max-Planck Institute of Biochemistry, Am Klopferspitz 18, 82152 Martinsried, Germany.
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Hong X, Lei L, Künert B, Naredla R, Applequist SE, Grandien A, Glas R. Tripeptidyl-peptidase II Controls DNA Damage Responses and In vivo γ-Irradiation Resistance of Tumors. Cancer Res 2007; 67:7165-74. [PMID: 17671184 DOI: 10.1158/0008-5472.can-06-4094] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Cellular responses to gamma-irradiation exposure are controlled by phosphatidylinositol 3-kinase-related kinases (PIKK) in the nucleus, and in addition, cytosolic PIKKs may have a role in such responses. Here, we show that the expression of tripeptidyl-peptidase II (TPPII), a high molecular weight cytosolic peptidase, required PIKK signaling and that TPPII was rapidly translocated into the nucleus of gamma-irradiated cells. These events were dependent on mammalian target of rapamycin, a cytosolic/mitochondrial PIKK that is activated by gamma-irradiation. Lymphoma cells with inhibited expression of TPPII failed to efficiently stabilize p53 and had reduced ability to arrest proliferation in response to gamma-irradiation. We observed that TPPII contains a BRCA COOH-terminal-like motif, contained within sequences of several proteins involved in DNA damage signaling pathways, and this motif was important for nuclear translocation of TPPII and stabilization of p53. Novel tripeptide-based inhibitors of TPPII caused complete in vivo tumor regression in mice in response to relatively low doses of gamma-irradiation (3-4 Gy/wk). This was observed with established mouse and human tumors of diverse tissue backgrounds, with no tumor regrowth after cancellation of treatment. These TPPII inhibitors had minor effects on tumor growth as single agent and had low cellular toxicity. Our data indicated that TPPII connects signaling by cytosolic/mitochondrial and nuclear PIKK-dependent pathways and that TPPII can be targeted for inhibition of tumor therapy resistance.
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Affiliation(s)
- Xu Hong
- Center for Infectious Medicine, Department of Medicine, Karolinska Institutet, Karolinska University Hospital-Huddinge
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