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Hu B, Wang J, Li Y, Ge J, Pan J, Li G, He Y, Zhong H, Wang B, Huang Y, Han S, Xing Y, He H. Gut microbiota facilitates adaptation of the plateau zokor ( Myospalax baileyi) to the plateau living environment. Front Microbiol 2023; 14:1136845. [PMID: 36910168 PMCID: PMC9998695 DOI: 10.3389/fmicb.2023.1136845] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Accepted: 02/06/2023] [Indexed: 03/14/2023] Open
Abstract
Gut microbiota not only helps the hosts to perform many key physiological functions such as food digestion, energy harvesting and immune regulation, but also influences host ecology and facilitates adaptation of the host to extreme environments. Plateau zokors epitomize successful physiological adaptation to their living environment in the face of the harsh environment characterized by low temperature, low pressure and hypoxia in the Tibetan plateau region and high concentrations of CO2 in their burrows. Therefore, here we used a metagenomic sequencing approach to explore how gut microbiota contributed to the adaptive evolution of the plateau zokor on the Qinghai-Tibet Plateau. Our metagenomic results show that the gut microbiota of plateau zokors on the Tibetan plateau is not only enriched in a large number of species related to energy metabolism and production of short-chain fatty acids (SCFAs), but also significantly enriched the KO terms that involve carbohydrate uptake pathways, which well address energy uptake in plateau zokors while also reducing inflammatory responses due to low pressure, hypoxia and high CO2 concentrations. There was also a significant enrichment of tripeptidyl-peptidase II (TPPII) associated with antigen processing, apoptosis, DNA damage repair and cell division, which may facilitate the immune response and tissue damage repair in plateau zokors under extreme conditions. These results suggest that these gut microbiota and their metabolites together contribute to the physiological adaptation of plateau zokors, providing new insights into the contribution of the microbiome to the evolution of mammalian adaptation.
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Affiliation(s)
- Bin Hu
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Jiamin Wang
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Ying Li
- College of Agriculture and Animal Husbandry, Qinghai University, Xining, China
| | - Jin Ge
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Jinchao Pan
- College of Animal Sciences, Anhui University of Science and Technology, Huainan, China
| | - Gaojian Li
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Yongcai He
- College of Agriculture and Animal Husbandry, Qinghai University, Xining, China
| | - Haishun Zhong
- Animal Husbandry and Veterinary Station of Xunhua, Xining, Qinghai, China
| | - Bo Wang
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Yanyi Huang
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Shuyi Han
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Yanan Xing
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China.,College of Life Science, University of Chinese Academy of Sciences, Beijing, China
| | - Hongxuan He
- Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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2
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Nahálková J. Linking TPPII to the protein interaction and signalling networks. Comput Biol Chem 2020; 87:107291. [PMID: 32702546 DOI: 10.1016/j.compbiolchem.2020.107291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 04/21/2020] [Accepted: 05/22/2020] [Indexed: 01/18/2023]
Abstract
Tripeptidyl peptidase II (TPPII) is primarily considered a house-keeping exopeptidase, which contributes to the functions of the ubiquitin-proteasome system by the maintenance of the cellular amino acid homeostasis. Although functionally well-characterised in vitro and using the mammalian cell models, less is known about the molecular mechanisms of its involvement in the signalling and metabolic pathways, which mediate its cellular functions. The present protein-protein interaction network analysis identified these mechanisms involved in the adaptive and innate immunity, the metabolism of the glucose, cancer cell growth, apoptosis, cell cycle and DNA damage responses. The interaction network constructed based on the publicly available protein-protein interaction data was extended by the application GeneMania, which was further used for the pathway enrichment, the protein function prediction and the protein node prioritisation analysis. The analysis suggested that the molecular mechanisms linked to the adaptive and innate immunity (ID, Kit receptor, BCR, IL-2 and G-CSF signalling; the regulation of NFκB), the aerobic glycolysis (ID and IL-2 signalling), tumorigenesis (TGF-β and p53 signalling; the top priority nodes MAPKs, mTOR regulation), diabetes (Kit receptor signalling; the top priority node GSK3β) and neurodegeneration (the control of mTOR and Aβ peptide degradation) are controlling the resulting TPPII interaction network. The uncharacterized interactions with two lung cancer suppressors (DOK3, DENND2D), a protein involved in the increased risk of the lung cancer in smokers (CYP1A1) and a protein implicated in asthmatic reactions (CHIA) suggest potential roles of TPPII in the lung cancer pathology. The interactions with methyltransferase CARNMT1, which modifies di- and tripeptides and the xenobiotic processing enzyme CYP1A1, are additional candidates for the breakthrough in new functions discovery of TPPII.
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Affiliation(s)
- Jarmila Nahálková
- Biochemworld Co., Biochemistry, Molecular & Cell Biology Unit, Snickar-Anders väg 17, 74394, Skyttorp, Uppsala County, Sweden.
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3
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Dong C, Tu W, He M, Fu J, Kobayashi A, Konishi T, Shao C. Role of Endoplasmic Reticulum and Mitochondrion in Proton Microbeam Radiation-Induced Bystander Effect. Radiat Res 2019; 193:63-72. [PMID: 31714866 DOI: 10.1667/rr15469.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
It is well known that mitochondria and the endoplasmic reticulum (ER) play important roles in radiation response, but their functions in radiation-induced bystander effect (RIBE) are largely unclear. In this study, we found that when a small portion of cells in a population of human lung fibroblast MRC-5 cells were precisely irradiated through either the nuclei or cytoplasm with counted microbeam protons, the yield of micronuclei (MN) and the levels of intracellular reactive oxygen species (ROS) in nonirradiated cells neighboring irradiated cells were significantly increased. Mito/ER-tracker staining demonstrated that the mitochondria were clearly activated after nuclear irradiation and ER mass approached a higher level after cytoplasmic irradiation. Moreover, the radiation-induced ROS was diminished by rotenone, an inhibitor of mitochondria activation, but it was not influenced by siRNA interference of BiP, an ER regulation protein. While for nuclear irradiation, rotenone-enhanced radiation-induced ER expression, and BiP siRNA eliminated radiation-induced activation of mitochondria, these phenomena were not observed for cytoplasmic irradiation. Bystander MN was reduced by rotenone but enhanced by BiP siRNA. When the cells were treated with both rotenone and BiP siRNA, the MN yield was reduced for nuclear irradiation but was enhanced for cytoplasmic irradiation. Our results suggest that the organelles of mitochondria and ER have different roles in RIBE with respect to nuclear and cytoplasmic irradiation, and the function of ER is a prerequisite for mitochondrial activation.
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Affiliation(s)
- Chen Dong
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
| | - Wenzhi Tu
- The Comprehensive Cancer Center, Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 201620, China
| | - Mingyuan He
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
| | - Jiamei Fu
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
| | - Alisa Kobayashi
- Department of Accelerator and Medical Physics, National Institute of Radiological Sciences
| | - Teruaki Konishi
- Department of Single Cell Radiation Biology Group, Institute for Quantum Life Science, National Institutes for Quantum and Radiological Science and Technology, Inage, Chiba 263-8555, Japan
| | - Chunlin Shao
- Institute of Radiation Medicine, Fudan University, Shanghai 200032, China
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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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5
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Nahálková J. Novel protein-protein interactions of TPPII, p53, and SIRT7. Mol Cell Biochem 2015; 409:13-22. [PMID: 26169984 DOI: 10.1007/s11010-015-2507-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2015] [Accepted: 07/04/2015] [Indexed: 12/27/2022]
Abstract
Novel protein-protein interactions of TPPII, SIRT7, and p53 were detected by co-immunoprecipitation using both HeLa cell lysates and the cytoplasmic fraction prepared by fractionation of mouse liver tissue. The interactions were further verified in vivo by in situ proximity ligation assay (PLA) within control HEK293 cells transformed with empty vector, highactTPPII HEK293 cells over-expressing murine TPPII displaying high specific enzymatic activity and in lowactTPPII HEK293 cells over-expressing human TPPII having low specific activity of the enzyme. Besides an abundant cytoplasmic localization of TPPII-p53 interaction signal, the nuclear interactions were also demonstrated. The cytoplasmic interactions were likewise detected between TPPII and SIRT7 in control HEK293 and lowactTPPII HEK293 cells. The interactions of SIRT7 with p53 were confirmed in three HEK293 cell transformants as well. The cytoplasmic occurrence of SIRT7 protein was demonstrated by immunofluorescence, when both nucleolar and cytoplasmic signals were identified within HEK293 cells and primary human fibroblasts. The unique cytoplasmic localization of SIRT7 protein was discussed based on an epitope specificity of N-terminus specific SIRT7 antibodies utilized in the present study compared with C-terminus specific antibodies previously used for nuclear detection of SIRT7 by other authors. The epitope sequence of N-terminal antibodies is occurring in all three splicing variants of SIRT7 compared to the epitope of C-terminal antibody, which is specific exclusively to the splicing variant 1. The cytoplasmic localization of p53 detected by immunofluorescence supported the results from its interactions with TPPII and SIRT7 observed by in situ PLA within model cells. Novel interactions of TPPII, p53, and SIRT7 presented in this study might contribute to the knowledge of the regulatory effects of these proteins on apoptotic pathways and to the understanding mechanisms of aging and lifespan regulation.
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Affiliation(s)
- Jarmila Nahálková
- Department of Medical Biochemistry and Microbiology (IMBIM), BMC, Uppsala University, Box 582, 751 23, Uppsala, Sweden.
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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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Nahálková J, Tomkinson B. TPPII, MYBBP1A and CDK2 form a protein–protein interaction network. Arch Biochem Biophys 2014; 564:128-35. [DOI: 10.1016/j.abb.2014.09.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Revised: 09/24/2014] [Accepted: 09/28/2014] [Indexed: 01/09/2023]
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8
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Schülke S, Dreidax D, Malik A, Burmester T, Nevo E, Band M, Avivi A, Hankeln T. Living with stress: regulation of antioxidant defense genes in the subterranean, hypoxia-tolerant mole rat, Spalax. Gene 2012; 500:199-206. [PMID: 22441129 DOI: 10.1016/j.gene.2012.03.019] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2011] [Revised: 02/01/2012] [Accepted: 03/05/2012] [Indexed: 12/12/2022]
Abstract
Lack of oxygen is life threatening for most mammals. It is therefore of biomedical interest to investigate the adaptive mechanisms which enable mammalian species to tolerate extremely hypoxic conditions. The subterranean mole rat Spalax survives substantially longer periods of hypoxia than the laboratory rat. We hypothesized that genes of the antioxidant defense, detoxifying harmful reactive oxygen species generated during hypoxia and hyperoxia, are involved in Spalax underground adaptation. Using quantitative RT-PCR, we analyzed the mRNA expression levels of seven antioxidant defense genes (catalase, glutathione peroxidase 1, glutathione-S-transferase Pi1, heme oxygenase 1, superoxide dismutase 1 and 2) and a master regulator of this stress pathway, nuclear factor (erythroid-derived 2)-like 2 (Nrf2) in several tissues of two Israeli Spalax species, S. galili (2n=52) and S. judaei (2n=60), and rat. We also studied the differential expression of these genes after experimental hypoxia and hyperoxia as oxidative stress treatments. We found that mRNA levels and transcriptional responses are species and tissue specific. There are constitutively higher transcript levels of antioxidant genes and their transcription factor Nrf2 in Spalax tissue as compared to rat, suggesting an increased ability in the mole rat to withstand hypoxic/hyperoxic insults. In contrast to Spalax, the rat reacts to experimental oxidative stress by changes in gene regulation. In addition, Spalax Nrf2 reveals unique amino acid changes, which may be functionally important for this transcription factor and indicate positive (Darwinian) selection. Antioxidant defense genes are therefore important targets for adaptive change during evolution of hypoxia tolerance in Spalax.
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Affiliation(s)
- Stefan Schülke
- Institute of Molecular Genetics, Johannes Gutenberg University, Mainz, Germany
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9
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Scythe cleavage during Fas (APO-1)-and staurosporine-mediated apoptosis. FEBS Lett 2012; 586:747-52. [PMID: 22285488 DOI: 10.1016/j.febslet.2012.01.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 01/17/2012] [Indexed: 11/21/2022]
Abstract
Scythe is a nuclear protein that has been implicated in the apoptotic process in Drosophila melanogaster; however, its role in apoptosis of mammalian cells is not fully elucidated. Here we show that cleavage of Scythe by caspase-3 occurs after activation of both the extrinsic (i.e. Fas/APO-1-mediated) and the intrinsic (i.e. staurosporine-induced) apoptosis pathway. Moreover, this caspase-dependent cleavage correlates with Scythe translocation from the nucleus to the cytosol. We also show that cytosolic re-localization of Scythe is required for Fas/APO-1-triggered phosphatidylserine (PS) exposure, a signal for macrophage clearance of apoptotic cells. Our data suggest that Scythe cleavage may represent a marker for caspase-3 activation and implicate cytosolic re-localization of Scythe in the pathway of PS exposure.
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10
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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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11
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Glas R, Grandien A, Applequist S, Kunert B, Naredla R. Retraction: Tripeptidyl-peptidase II controls DNA damage responses and in vivo γ-irradiation resistance of tumors. Cancer Research 2007;67:7165–74. Cancer Res 2010; 70:10485. [PMID: 21159658 DOI: 10.1158/0008-5472.can-10-3913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Rickard Glas
- Center for Molecular Medicine (CMM), Karolinska Universitetssjukhuset, Stockholm, Sweden
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12
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He M, Zhao M, Shen B, Prise KM, Shao C. Radiation-induced intercellular signaling mediated by cytochrome-c via a p53-dependent pathway in hepatoma cells. Oncogene 2010; 30:1947-55. [PMID: 21132005 DOI: 10.1038/onc.2010.567] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The tumor suppressor p53 has a crucial role in cellular response to DNA damage caused by ionizing radiation, but it is still unclear whether p53 can modulate radiation-induced bystander effects (RIBE). In the present work, three different hepatoma cell lines, namely HepG2 (wild p53), PLC/PRF/5 (mutation p53) and Hep3B (p53 null), were irradiated with γ-rays and then co-cultured with normal Chang liver cell (wild p53) in order to elucidate the mechanisms of RIBE. Results showed that the radiosensitivity of HepG2 cells was higher than that of PLC/PRF/5 and Hep3B cells. Only irradiated HepG2 cells, rather than irradiated PLC/PRF/5 or Hep3B cells, could induce bystander effect of micronuclei (MN) formation in the neighboring Chang liver cells. When HepG2 cells were treated with 20 μM pifithrin-α, an inhibitor of p53 function, or 5 μM cyclosporin A (CsA), an inhibitor of cytochrome-c release from mitochondria, the MN induction in bystander Chang liver cells was diminished. In fact, it was found that after irradiation, cytochrome-c was released from mitochondria into the cytoplasm only in HepG2 cells in a p53-dependent manner, but not in PLC/PRF/5 and Hep3B cells. Interestingly, when 50 μg/ml exogenous cytochrome-c was added into cell co-culture medium, RIBE was significantly triggered by irradiated PLC/PRF/5 and Hep3B cells, which previously failed to provoke a bystander effect. In addition, this exogenous cytochrome-c also partly recovered the RIBE induced by irradiated HepG2 cells even with CsA treatment. Our results provide new evidence that the RIBE can be modulated by the p53 status of irradiated hepatoma cells and that a p53-dependent release of cytochrome-c may be involved in the RIBE.
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Affiliation(s)
- M He
- Institute of Radiation Medicine, Fudan University, Shanghai, China
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13
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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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Preta G, de Klark R, Chakraborti S, Glas R. MAP kinase-signaling controls nuclear translocation of tripeptidyl-peptidase II in response to DNA damage and oxidative stress. Biochem Biophys Res Commun 2010; 399:324-30. [DOI: 10.1016/j.bbrc.2010.06.133] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2010] [Accepted: 06/30/2010] [Indexed: 01/14/2023]
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