1
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Nguyen HD, Kim WK, Huong Vu G. Molecular mechanisms implicated in protein changes in the Alzheimer's disease human hippocampus. Mech Ageing Dev 2024; 219:111930. [PMID: 38554950 DOI: 10.1016/j.mad.2024.111930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2023] [Revised: 01/18/2024] [Accepted: 03/25/2024] [Indexed: 04/02/2024]
Abstract
This study aimed to elucidate the specific biochemical pathways linked to changes in proteins in the Alzheimer's disease (AD) human hippocampus. Our data demonstrate a constant rise in the expression of four proteins (VGF, GFAP, HSPB1, and APP) across all eleven studies. Notably, UBC was the most centrally involved and had increased expression in the hippocampus tissue of individuals with AD. Modified proteins in the hippocampal tissue were found to activate the innate immune system and disrupt communication across chemical synapses. Four hub proteins (CD44, APP, ITGB2, and APOE) are connected to amyloid plaques, whereas two hub proteins (RPL24 and RPS23) are related to neurofibrillary tangles (NFTs). The presence of modified proteins was discovered to trigger the activation of microglia and decrease the functioning of ribosomes and mitochondria in the hippocampus. Three significant microRNAs (hsa-miR-106b-5p, hsa-miR-17-5p, and hsa-miR-16-5p) and transcription factors (MYT1L, PIN1, and CSRNP3) have been discovered to improve our understanding of the alterations in proteins within the hippocampal tissues that lead to the progression of AD. These findings establish a path for possible treatments for AD to employ therapeutic strategies that specifically focus on the proteins or processes linked to the illness.
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Affiliation(s)
- Hai Duc Nguyen
- Department of Pharmacy, College of Pharmacy and Research Institute of Life and Pharmaceutical Sciences, Sunchon National University, Suncheon 57922, Republic of Korea; Division of Microbiology, Tulane National Primate Research Center, Tulane University, Louisiana, USA.
| | - Woong-Ki Kim
- Division of Microbiology, Tulane National Primate Research Center, Tulane University, Louisiana, USA; Department of Microbiology and Immunology, Tulane University School of Medicine, New Orleans, Louisiana, USA
| | - Giang Huong Vu
- Department of Public Health, Hong Bang Health Center, Hai Phong, Vietnam
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2
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Ashok A, Kalthur G, Kumar A. Degradation meets development: Implications in β-cell development and diabetes. Cell Biol Int 2024; 48:759-776. [PMID: 38499517 DOI: 10.1002/cbin.12155] [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: 11/03/2023] [Revised: 02/22/2024] [Accepted: 03/04/2024] [Indexed: 03/20/2024]
Abstract
Pancreatic development is orchestrated by timely synthesis and degradation of stage-specific transcription factors (TFs). The transition from one stage to another stage is dependent on the precise expression of the developmentally relevant TFs. Persistent expression of particular TF would impede the exit from the progenitor stage to the matured cell type. Intracellular protein degradation-mediated protein turnover contributes to a major extent to the turnover of these TFs and thereby dictates the development of different tissues. Since even subtle changes in the crucial cellular pathways would dramatically impact pancreatic β-cell performance, it is generally acknowledged that the biological activity of these pathways is tightly regulated by protein synthesis and degradation process. Intracellular protein degradation is executed majorly by the ubiquitin proteasome system (UPS) and Lysosomal degradation pathway. As more than 90% of the TFs are targeted to proteasomal degradation, this review aims to examine the crucial role of UPS in normal pancreatic β-cell development and how dysfunction of these pathways manifests in metabolic syndromes such as diabetes. Such understanding would facilitate designing a faithful approach to obtain a therapeutic quality of β-cells from stem cells.
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Affiliation(s)
- Akshaya Ashok
- Manipal Institute of Regenerative Medicine, Bangalore, Manipal Academy of Higher Education, Manipal, India
| | - Guruprasad Kalthur
- Division of Reproductive and Developmental Biology, Department of Reproductive Science, Kasturba Medical College, Manipal Academy of Higher Education, Manipal, India
| | - Anujith Kumar
- Manipal Institute of Regenerative Medicine, Bangalore, Manipal Academy of Higher Education, Manipal, India
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3
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Zhang Z, Li M, Lin P, Ren Y, He Y, Wang S, Xu Y, Cao B, Wang G, Moran MF, Mao X. The ubiquitin ligase HERC4 suppresses MafA transcriptional activity triggered by GSK3β in myeloma by atypical K63-linked polyubiquitination. J Biol Chem 2023; 299:104675. [PMID: 37028761 DOI: 10.1016/j.jbc.2023.104675] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2022] [Revised: 03/23/2023] [Accepted: 03/29/2023] [Indexed: 04/09/2023] Open
Abstract
MafA and c-Maf are close members of the Maf transcription factor family and indicators of poor prognosis of multiple myeloma (MM). Our previous study finds that the ubiquitin ligase HERC4 induces c-Maf degradation but stabilizes MafA, and the mechanism is elusive. In the present study we find that HERC4 interacts with MafA and mediates its K63-linked polyubiquitination at K33. Moreover, HERC4 inhibits MafA phosphorylation and its transcriptional activity triggered by glycogen synthase kinase 3β (GSK3β). The K33R MafA variant prevents HERC4 from inhibiting MafA phosphorylation and increases MafA transcriptional activity. Further analyses reveal that MafA can also activate the STAT3 signaling but it is suppressed by HERC4. Lastly, we demonstrate that lithium chloride, a GSK3β inhibitor, can upregulate HERC4 and synergizes dexamethasone, a typical anti-MM drug, in inhibiting MM cell proliferation and xenograft growth in nude mice. These findings thus highlight a novel regulation of MafA oncogenic activity in MM and provide the rationale by targeting HERC4/GSK3β/MafA for the treatment of MM.
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Affiliation(s)
- Zubin Zhang
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China.
| | - Mei Li
- Institute of Pediatric Research, Children's Hospital of Soochow University, Suzhou, Jiangsu, 215025, China
| | - Peng Lin
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Ying Ren
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Yuanming He
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Siyu Wang
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Yujia Xu
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Biyin Cao
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Guanghui Wang
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China
| | - Michael F Moran
- The Department of Molecular Genetics, The University of Toronto, Toronto, ON, M5G 0A4, Canada
| | - Xinliang Mao
- Jiangsu Key Laboratory for Translational Research and Therapeutics of NeuroPsychoDiseases, Department of Pharmacology, College of Pharmaceutical Sciences, Soochow University, Suzhou, Jiangsu, 215123, China; Guangdong Provincial Key Laboratory of Protein Modification and Degradation, State Key Laboratory of Respiratory Diseases, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, Guangdong, 511436, China.
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4
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Liang J, Chirikjian M, Pajvani UB, Bartolomé A. MafA Regulation in β-Cells: From Transcriptional to Post-Translational Mechanisms. Biomolecules 2022; 12:biom12040535. [PMID: 35454124 PMCID: PMC9033020 DOI: 10.3390/biom12040535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 03/29/2022] [Accepted: 03/30/2022] [Indexed: 11/17/2022] Open
Abstract
β-cells are insulin-producing cells in the pancreas that maintain euglycemic conditions. Pancreatic β-cell maturity and function are regulated by a variety of transcription factors that enable the adequate expression of the cellular machinery involved in nutrient sensing and commensurate insulin secretion. One of the key factors in this regulation is MAF bZIP transcription factor A (MafA). MafA expression is decreased in type 2 diabetes, contributing to β-cell dysfunction and disease progression. The molecular biology underlying MafA is complex, with numerous transcriptional and post-translational regulatory nodes. Understanding these complexities may uncover potential therapeutic targets to ameliorate β-cell dysfunction. This article will summarize the role of MafA in normal β-cell function and disease, with a special focus on known transcriptional and post-translational regulators of MafA expression.
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Affiliation(s)
- Jiani Liang
- Department of Medicine, Columbia University, New York, NY 10032, USA; (J.L.); (M.C.); (U.B.P.)
| | - Margot Chirikjian
- Department of Medicine, Columbia University, New York, NY 10032, USA; (J.L.); (M.C.); (U.B.P.)
| | - Utpal B. Pajvani
- Department of Medicine, Columbia University, New York, NY 10032, USA; (J.L.); (M.C.); (U.B.P.)
| | - Alberto Bartolomé
- Instituto de Investigaciones Biomédicas Alberto Sols, CSIC-UAM, 28029 Madrid, Spain
- Correspondence:
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5
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Functional Differences between Proteasome Subtypes. Cells 2022; 11:cells11030421. [PMID: 35159231 PMCID: PMC8834425 DOI: 10.3390/cells11030421] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/11/2022] [Accepted: 01/14/2022] [Indexed: 12/30/2022] Open
Abstract
Four proteasome subtypes are commonly present in mammalian tissues: standard proteasomes, which contain the standard catalytic subunits β1, β2 and β5; immunoproteasomes containing the immuno-subunits β1i, β2i and β5i; and two intermediate proteasomes, containing a mix of standard and immuno-subunits. Recent studies revealed the expression of two tissue-specific proteasome subtypes in cortical thymic epithelial cells and in testes: thymoproteasomes and spermatoproteasomes. In this review, we describe the mechanisms that enable the ATP- and ubiquitin-dependent as well as the ATP- and ubiquitin-independent degradation of proteins by the proteasome. We focus on understanding the role of the different proteasome subtypes in maintaining protein homeostasis in normal physiological conditions through the ATP- and ubiquitin-dependent degradation of proteins. Additionally, we discuss the role of each proteasome subtype in the ATP- and ubiquitin-independent degradation of disordered proteins. We also discuss the role of the proteasome in the generation of peptides presented by MHC class I molecules and the implication of having different proteasome subtypes for the peptide repertoire presented at the cell surface. Finally, we discuss the role of the immunoproteasome in immune cells and its modulation as a potential therapy for autoimmune diseases.
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6
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Boulpicante M, Darrigrand R, Pierson A, Salgues V, Rouillon M, Gaudineau B, Khaled M, Cattaneo A, Bachi A, Cascio P, Apcher S. Tumors escape immunosurveillance by overexpressing the proteasome activator PSME3. Oncoimmunology 2020; 9:1761205. [PMID: 32923122 PMCID: PMC7458623 DOI: 10.1080/2162402x.2020.1761205] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 04/03/2020] [Indexed: 11/09/2022] Open
Abstract
The success of CD8+ T cell-based cancer immunotherapy emphasizes the importance of understanding the mechanisms of generation of MHC-I peptide ligands and the possible pathways of tumor cell escape from immunosurveillance. Recently, we showed that peptides generated in the nucleus during a pioneer round of mRNA translation (pioneer translation products, or PTPs) are an important source of tumor specific peptides which correlates with the aberrant splicing and transcription events associated with oncogenesis. Here we show that up-regulation of PSME3 proteasome activator in cancer cells results in increased destruction of PTP-derived peptides in the nucleus thus enabling cancer cell to subvert immunosurveillance. These findings unveil a previously unexpected role for PSME3 in antigen processing and identify PSME3 as a druggable target to improve the efficacy of cancer immunotherapy.
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Affiliation(s)
- Mathilde Boulpicante
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Romain Darrigrand
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Alison Pierson
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Valérie Salgues
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Marine Rouillon
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Benoit Gaudineau
- Dynamique des Cellules Tumorales, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Mehdi Khaled
- Dynamique des Cellules Tumorales, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
| | - Angela Cattaneo
- IFOM, The FIRC Institute of Molecular Oncology, Milano, Italy
| | - Angela Bachi
- IFOM, The FIRC Institute of Molecular Oncology, Milano, Italy
| | - Paolo Cascio
- Department of Veterinary Sciences, University of Turin, 10095, Grugliasco, Turin, Italy
| | - Sébastien Apcher
- Immunologie des Tumeurs et Immunothérapie, Université Paris-Saclay, Institut Gustave Roussy, Inserm, Villejuif, France
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7
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Coux O, Zieba BA, Meiners S. The Proteasome System in Health and Disease. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2020; 1233:55-100. [DOI: 10.1007/978-3-030-38266-7_3] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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8
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Schipper-Krom S, Sanz AS, van Bodegraven EJ, Speijer D, Florea BI, Ovaa H, Reits EA. Visualizing Proteasome Activity and Intracellular Localization Using Fluorescent Proteins and Activity-Based Probes. Front Mol Biosci 2019; 6:56. [PMID: 31482094 PMCID: PMC6710370 DOI: 10.3389/fmolb.2019.00056] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/02/2019] [Indexed: 12/18/2022] Open
Abstract
The proteasome is a multi-catalytic molecular machine that plays a key role in the degradation of many cytoplasmic and nuclear proteins. The proteasome is essential and proteasome malfunction is associated with various disease pathologies. Proteasome activity depends on its catalytic subunits which are interchangeable and also on the interaction with the associated regulatory cap complexes. Here, we describe and compare various methods that allow the study of proteasome function in living cells. Methods include the use of fluorescently tagged proteasome subunits and the use of activity-based proteasome probes. These probes can be used in both biochemical assays and in microscopy-based experiments. Together with tagged proteasomes, they can be used to study proteasome localization, dynamics, and activity.
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Affiliation(s)
- Sabine Schipper-Krom
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Alicia Sanz Sanz
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Emma J. van Bodegraven
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Dave Speijer
- Department of Medical Biochemistry, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
| | - Bogdan I. Florea
- Leiden Institute of Chemistry, Leiden University, Leiden, Netherlands
| | - Huib Ovaa
- Department of Cell and Chemical Biology, Leiden University Medical Center, Oncode Institute, Leiden, Netherlands
| | - Eric A. Reits
- Department of Medical Biology, Academic Medical Center, University of Amsterdam, Amsterdam, Netherlands
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9
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Morozov AV, Karpov VL. Proteasomes and Several Aspects of Their Heterogeneity Relevant to Cancer. Front Oncol 2019; 9:761. [PMID: 31456945 PMCID: PMC6700291 DOI: 10.3389/fonc.2019.00761] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 07/29/2019] [Indexed: 01/19/2023] Open
Abstract
The life of every organism is dependent on the fine-tuned mechanisms of protein synthesis and breakdown. The degradation of most intracellular proteins is performed by the ubiquitin proteasome system (UPS). Proteasomes are central elements of the UPS and represent large multisubunit protein complexes directly responsible for the protein degradation. Accumulating data indicate that there is an intriguing diversity of cellular proteasomes. Different proteasome forms, containing different subunits and attached regulators have been described. In addition, proteasomes specific for a particular tissue were identified. Cancer cells are highly dependent on the proper functioning of the UPS in general, and proteasomes in particular. At the same time, the information regarding the role of different proteasome forms in cancer is limited. This review describes the functional and structural heterogeneity of proteasomes, their association with cancer as well as several established and novel proteasome-directed therapeutic strategies.
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Affiliation(s)
- Alexey V. Morozov
- Laboratory of Regulation of Intracellular Proteolysis, W.A. Engelhardt Institute of Molecular Biology RAS, Moscow, Russia
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10
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Murray D, Mirzayans R, McBride WH. Defenses against Pro-oxidant Forces - Maintenance of Cellular and Genomic Integrity and Longevity. Radiat Res 2018; 190:331-349. [PMID: 30040046 PMCID: PMC6203329 DOI: 10.1667/rr15101.1] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
There has been enormous recent progress in understanding how human cells respond to oxidative stress, such as that caused by exposure to ionizing radiation. We have witnessed a significant deciphering of the events that underlie how antioxidant responses counter pro-oxidant damage to key biological targets in all cellular compartments, including the genome and mitochondria. These cytoprotective responses include: 1. The basal cellular repertoire of antioxidant capabilities and its supporting cast of facilitator enzymes; and 2. The inducible phase of the antioxidant response, notably that mediated by the Nrf2 transcription factor. There has also been frenetic progress in defining how reactive electrophilic species swamp existing protective mechanisms to augment DNA damage, events that are embodied in the cellular "DNA-damage response", including cell cycle checkpoint activation and DNA repair, which occur on a time scale of hours to days, as well as the implementation of cellular responses such as apoptosis, autophagy, senescence and reprograming that extend the time period of damage sensing and response into weeks, months and years. It has become apparent that, in addition to the initial oxidative insult, cells typically undergo further waves of secondary reactive oxygen/nitrogen species generation, DNA damage and signaling and that these may reemerge long after the initial events have subsided, probably being driven, at least in part, by persisting DNA damage. These reactive oxygen/nitrogen species are an integral part of the pathological consequences of radiation exposure and may persist across multiple cell divisions. Because of the pervasive nature of oxidative stress, a cell will manifest different responses in different subcellular compartments and to different levels of stress injury. Aspects of these compartmentalized responses can involve the same proteins (such as ATM, p53 and p21) but in different functional guises, e.g., in cytoplasmic versus nuclear responses or in early- versus late-phase events. Many of these responses involve gene activation and new protein synthesis as well as a plethora of post-translational modifications of both basal and induced response proteins. It is these responses that we focus on in this review.
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Affiliation(s)
- David Murray
- Department of Oncology, Division of Experimental Oncology, University of Alberta and Cross Cancer Institute, Edmonton, Canada
| | - Razmik Mirzayans
- Department of Oncology, Division of Experimental Oncology, University of Alberta and Cross Cancer Institute, Edmonton, Canada
| | - William H. McBride
- Department of Radiation Oncology, University of California, Los Angeles (UCLA), Los Angeles, California
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11
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Jiang TX, Zhao M, Qiu XB. Substrate receptors of proteasomes. Biol Rev Camb Philos Soc 2018; 93:1765-1777. [DOI: 10.1111/brv.12419] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 03/26/2018] [Accepted: 03/28/2018] [Indexed: 01/01/2023]
Affiliation(s)
- Tian-Xia Jiang
- State Key Laboratory of Cognitive Neuroscience & Learning and Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences; Beijing Normal University, 19 Xinjiekouwai Avenue; Beijing 100875 China
| | - Mei Zhao
- State Key Laboratory of Cognitive Neuroscience & Learning and Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences; Beijing Normal University, 19 Xinjiekouwai Avenue; Beijing 100875 China
| | - Xiao-Bo Qiu
- State Key Laboratory of Cognitive Neuroscience & Learning and Ministry of Education Key Laboratory of Cell Proliferation & Regulation Biology, College of Life Sciences; Beijing Normal University, 19 Xinjiekouwai Avenue; Beijing 100875 China
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12
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Lundh M, Bugliani M, Dahlby T, Chou DHC, Wagner B, Ghiasi SM, De Tata V, Chen Z, Lund MN, Davies MJ, Marchetti P, Mandrup-Poulsen T. The immunoproteasome is induced by cytokines and regulates apoptosis in human islets. J Endocrinol 2017; 233:369-379. [PMID: 28438776 PMCID: PMC5501413 DOI: 10.1530/joe-17-0110] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 04/24/2017] [Indexed: 12/11/2022]
Abstract
In addition to degrading misfolded and damaged proteins, the proteasome regulates the fate of cells in response to stress. The role of the proteasome in pro-inflammatory cytokine-induced human beta-cell apoptosis is unknown. Using INS-1, INS-1E and human islets exposed to combinations of IFNγ, IL-1β and TNFα with or without addition of small molecules, we assessed the role of the immunoproteasome in pancreatic beta-cell demise. Here, we show that cytokines induce the expression and activity of the immuno-proteasome in INS-1E cells and human islets. Cytokine-induced expression of immuno-proteasome subunits, but not activity, depended upon histone deacetylase 3 activation. Inhibition of JAK1/STAT1 signaling did not affect proteasomal activity. Inhibition of the immuno-proteasome subunit PSMB8 aggravated cytokine-induced human beta-cell apoptosis while reducing intracellular levels of oxidized proteins in INS-1 cells. While cytokines increased total cellular NFκB subunit P50 and P52 levels and reduced the cytosolic NFκB subunit P65 and IκB levels, these effects were unaffected by PSMB8 inhibition. We conclude that beta cells upregulate immuno-proteasome expression and activity in response to IFNγ, likely as a protective response to confine inflammatory signaling.
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Affiliation(s)
- Morten Lundh
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
- Chemical Biology and Therapeutics ProgramBroad Institute of Harvard and MIT, Boston, Massachusetts, USA
| | - Marco Bugliani
- Department of Clinical and Experimental MedicineUniversity of Pisa, Pisa, Italy
| | - Tina Dahlby
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
| | - Danny Hung-Chieh Chou
- Chemical Biology and Therapeutics ProgramBroad Institute of Harvard and MIT, Boston, Massachusetts, USA
| | - Bridget Wagner
- Chemical Biology and Therapeutics ProgramBroad Institute of Harvard and MIT, Boston, Massachusetts, USA
| | | | - Vincenzo De Tata
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
| | - Zhifei Chen
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
| | - Marianne Nissan Lund
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
- Department of Food ScienceUniversity of Copenhagen, Copenhagen, Denmark
| | - Michael J Davies
- Department of Biomedical SciencesUniversity of Copenhagen, Copenhagen, Denmark
| | - Piero Marchetti
- Department of Clinical and Experimental MedicineUniversity of Pisa, Pisa, Italy
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13
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Han SI, Tsunekage Y, Kataoka K. Phosphorylation of MafA enhances interaction with Beta2/NeuroD1. Acta Diabetol 2016; 53:651-60. [PMID: 27017486 DOI: 10.1007/s00592-016-0853-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2015] [Accepted: 03/02/2016] [Indexed: 10/22/2022]
Abstract
AIMS MafA is a critical regulator of insulin expression and mature β-cell function. MafA binds to the insulin promoter through its carboxyl-terminal basic domain-leucine zipper (bZip) region and activates transcription synergistically with the β-cell-enriched transactivators Beta2 (NeuroD1) and Pdx1. MafA protein is highly phosphorylated in β-cells, and phosphorylation at multiple sites within its amino-terminal region is critical for its DNA-binding and transactivating abilities, as well as for regulation of its degradation. Here, we investigated whether phosphorylation of MafA affects its interaction with Beta2. METHODS By mutational analysis, we identified interaction domains of MafA and Beta2. Using in situ proximity ligation assay (PLA), we explored mechanism of phosphorylation-dependent binding of MafA with Beta2. We also searched for a pathophysiological condition that would induce lower levels of MafA phosphorylation. RESULTS Mutational analysis revealed that the phosphorylation sites within the amino-terminal region of MafA were not necessary for interaction with Beta2. In situ PLA suggested that phosphorylation induces conformational or configurational changes in MafA, thereby regulating the interaction with Beta2. We also found that long-term culture of the MIN6 insulinoma cell line under high-glucose conditions resulted in a decrease in β-cell-specific transcripts including insulin, along with a decrease in MafA phosphorylation and DNA binding. CONCLUSION Phosphorylation of MafA plays a critical role in β-cell function by regulating multiple functionalities, including binding to DNA, interaction with Beta2, and transactivation.
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Affiliation(s)
- Song-Iee Han
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
- Department of Internal Medicine (Endocrinology and Metabolism), Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, 305-8575, Japan
| | - Yukino Tsunekage
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan
| | - Kohsuke Kataoka
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama, 230-0045, Japan.
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14
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Han SI, Tsunekage Y, Kataoka K. Gata3 cooperates with Gcm2 and MafB to activate parathyroid hormone gene expression by interacting with SP1. Mol Cell Endocrinol 2015; 411:113-20. [PMID: 25917456 DOI: 10.1016/j.mce.2015.04.018] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Revised: 04/17/2015] [Accepted: 04/19/2015] [Indexed: 11/21/2022]
Abstract
Haploinsufficiency of the Gata3 gene, which encodes a zinc-finger transcription factor, is associated with the disorder hypoparathyroidism, deafness, and renal dysplasia (HDR) syndrome in humans. However, the roles of Gata3 in transcriptional regulation in the parathyroid glands are not well-understood. In this study, we show that Gata3 activates transcription of parathyroid hormone (PTH), which is secreted from parathyroid glands and is critical for regulating serum calcium and phosphate homeostasis. Gata3 interacted with Gcm2 and MafB, two known transcriptional regulators of parathyroid development, and synergistically stimulated the PTH promoter. An SP1-binding element (GC box) located within the PTH-promoter proximal region was critical for activating transcription by Gata3. In addition, the ubiquitous transcription factor SP1 also interacted with Gata3 as well as MafB and Gcm2, and HDR syndrome-associated Gata3 mutants were defective in activating the PTH promoter. These results suggest that Gata3 is a critical regulator of PTH gene expression.
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Affiliation(s)
- Song-Iee Han
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Yukino Tsunekage
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan
| | - Kohsuke Kataoka
- Laboratory of Molecular Medical Bioscience, Graduate School of Medical Life Science, Yokohama City University, 1-7-29 Suehiro-cho, Tsurumi-ku, Yokohama 230-0045, Japan.
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15
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Sánchez-Lanzas R, Castaño JG. Proteins directly interacting with mammalian 20S proteasomal subunits and ubiquitin-independent proteasomal degradation. Biomolecules 2014; 4:1140-54. [PMID: 25534281 PMCID: PMC4279173 DOI: 10.3390/biom4041140] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2014] [Revised: 11/25/2014] [Accepted: 12/11/2014] [Indexed: 12/12/2022] Open
Abstract
The mammalian 20S proteasome is a heterodimeric cylindrical complex (α7β7β7α7), composed of four rings each composed of seven different α or β subunits with broad proteolytic activity. We review the mammalian proteins shown to directly interact with specific 20S proteasomal subunits and those subjected to ubiquitin-independent proteasomal degradation (UIPD). The published reports of proteins that interact with specific proteasomal subunits, and others found on interactome databases and those that are degraded by a UIPD mechanism, overlap by only a few protein members. Therefore, systematic studies of the specificity of the interactions, the elucidation of the protein regions implicated in the interactions (that may or may not be followed by degradation) and competition experiments between proteins known to interact with the same proteasomal subunit, are needed. Those studies should provide a coherent picture of the molecular mechanisms governing the interactions of cellular proteins with proteasomal subunits, and their relevance to cell proteostasis and cell functioning.
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Affiliation(s)
- Raúl Sánchez-Lanzas
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas 'Alberto Sols', UAM-CSIC, Facultad de Medicina de la Universidad Autónoma de Madrid, Madrid 28029, Spain.
| | - José G Castaño
- Departamento de Bioquímica, Instituto de Investigaciones Biomédicas 'Alberto Sols', UAM-CSIC, Facultad de Medicina de la Universidad Autónoma de Madrid, Madrid 28029, Spain.
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16
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Gruner M, Moncsek A, Rödiger S, Kühnhardt D, Feist E, Stohwasser R. Increased proteasome activator 28 gamma (PA28γ) levels are unspecific but correlate with disease activity in rheumatoid arthritis. BMC Musculoskelet Disord 2014; 15:414. [PMID: 25482151 PMCID: PMC4295294 DOI: 10.1186/1471-2474-15-414] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 11/28/2014] [Indexed: 12/02/2022] Open
Abstract
BACKGROUND PA28γ (also known as Ki, REG gamma, PMSE3), a member of the ubiquitin-and ATP-independent proteasome activator family 11S, has been proved to show proteasome-dependent and -independent effects on several proteins including tumor suppressor p53, cyclin-dependent kinase inhibitor p21 and steroid receptor co-activator 3 (SCR-3). Interestingly, PA28γ is overexpressed in pathological tissue of various cancers affecting e. g. breast, bowl and thyroids. Furthermore, anti-PA28γ autoantibodies have been linked to several autoimmune disorders. The aim of this study was to develop and evaluate a novel and sensitive PA28γ sandwich ELISA for the quantification of PA28γ serum levels in patients with cancer and autoimmune diseases for diagnostic and prognostic purposes. METHODS PA28γ-specific polyclonal antibodies and recombinant His-tagged PA28γ were purified and used to develop a sandwich ELISA for the detection of circulating PA28γ. With this new assay, PA28γ serum levels of patients with various cancers, rheumatoid arthritis (RA), Sjögren's syndrome (SS), adult-onset Still's disease (AOSD) and different connective-tissue diseases (CTD) were compared with healthy control subjects. Anti-PA28γ autoantibodies were additionally confirmed using a newly developed microbead assay. RESULTS The developed PA28γ sandwich ELISA showed a high specificity with a detection limit of 3 ng/ml. A significant up-regulation of circulating PA28γ was detected in the sera of patients with cancer, RA, SS and CTD. A significant correlation was observed dependent on age as well as anti-PA28γ autoantibody levels with circulating PA28γ protein levels. Furthermore, PA28γ serum levels showed a correlation with disease activity in patients with RA under treatment with the T-cell directed biological compound abatacept according to disease activity score 28 (DAS28) and erythrocyte sedimentation rate (ESR). CONCLUSION The application of PA28γ as a novel biomarker for diagnostic purposes of a specific disease is limited, since elevated levels were observed in different disorders. However, the correlation with disease activity in patients with RA suggests a prognostic value, which needs to be addressed by further studies. Therefore our results show that PA28γ is a useful marker which should be included in studies related to novel treatments, e.g. abatacept.
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Affiliation(s)
- Melanie Gruner
- />Faculty of Natural Sciences, Brandenburg Technical University Cottbus - Senftenberg, Großenhainer Str. 57, D-01968 Senftenberg, Germany
- />Department of Rheumatology and Clinical Immunology and Autoinflammatory Reference Centre at Charité, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Anja Moncsek
- />Faculty of Natural Sciences, Brandenburg Technical University Cottbus - Senftenberg, Großenhainer Str. 57, D-01968 Senftenberg, Germany
- />Department of Biochemistry, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Stefan Rödiger
- />Faculty of Natural Sciences, Brandenburg Technical University Cottbus - Senftenberg, Großenhainer Str. 57, D-01968 Senftenberg, Germany
| | - Dagmar Kühnhardt
- />Department of Hematology and Oncology, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Eugen Feist
- />Department of Rheumatology and Clinical Immunology and Autoinflammatory Reference Centre at Charité, Charité-Universitätsmedizin Berlin, Charitéplatz 1, D-10117 Berlin, Germany
| | - Ralf Stohwasser
- />Faculty of Natural Sciences, Brandenburg Technical University Cottbus - Senftenberg, Großenhainer Str. 57, D-01968 Senftenberg, Germany
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Gu DN, Huang Q, Tian L. The molecular mechanisms and therapeutic potential of microRNA-7 in cancer. Expert Opin Ther Targets 2014; 19:415-26. [PMID: 25434362 DOI: 10.1517/14728222.2014.988708] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
INTRODUCTION Increasing evidence supports that microRNAs (miRNAs) play crucial roles in cancer through post-transcriptional gene silencing of their target genes, therefore, more and more effort has been devoted to develop miRNA-targeting therapeutics in cancer. MicroRNA-7 (miR-7) has been characterized as a potential tumor suppressor and regulates diverse fundamental biological processes of cancer cells including initiation, proliferation, migration, invasion, survival and death by targeting a number of oncogenic signaling pathways. AREAS COVERED This review examines evidence of the biological responses of miR-7 in cancer, with an emphasis on its regulation of the vital oncogenic signaling pathways. It also discusses the rationale, strategies and challenges of miR-7 as a potential therapeutic target for cancer. EXPERT OPINION With the increasing understanding of molecular mechanisms of miR-7-mediated regulatory networks and the advancement of miRNA-based therapeutics, targeting miR-7 may be a potential and promising strategy for cancer therapy.
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Affiliation(s)
- Dian-Na Gu
- Shanghai Jiao Tong University School of Medicine, Shanghai First People's Hospital, Experimental Research Center , Shanghai 201620 , PR China +86 21 37798755 ; +86 21 37798276 ;
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18
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Regulation of c-Myc protein stability by proteasome activator REGγ. Cell Death Differ 2014; 22:1000-11. [PMID: 25412630 DOI: 10.1038/cdd.2014.188] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 10/09/2014] [Accepted: 10/14/2014] [Indexed: 01/05/2023] Open
Abstract
c-Myc is a key transcriptional factor that has a prominent role in cell growth, differentiation and tumor development. Its protein levels are tightly controlled by ubiquitin-proteasome pathway and frequently deregulated in various cancers. Here, we report that the 11S proteasomal activator REGγ is a novel regulator of c-Myc abundance in cells. We showed that overexpression of wild-type REGγ, but not inactive mutants including N151Y and G250S, significantly promoted the degradation of c-Myc. Depletion of REGγ markedly increased the protein stability of c-Myc. REGγ interacts with the C-terminal region of c-Myc and regulates c-Myc protein turnover. Functionally, REGγ negatively regulates c-Myc-mediated cell proliferation. Interestingly, depletion of the Drosophila Reg homolog (dReg) in developing wings induced the upregulation of Drosophila Myc, which contributes to cell death. Collectively, these results suggest that REGγ proteasome has a conserved role in the regulation of Myc abundance in both mammalian cells and Drosophila.
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19
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Yan Q, Sharma-Kuinkel BK, Deshmukh H, Tsalik EL, Cyr DD, Lucas J, Woods CW, Scott WK, Sempowski GD, Thaden J, Rude TH, Ahn SH, Fowler VG. Dusp3 and Psme3 are associated with murine susceptibility to Staphylococcus aureus infection and human sepsis. PLoS Pathog 2014; 10:e1004149. [PMID: 24901344 PMCID: PMC4047107 DOI: 10.1371/journal.ppat.1004149] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 04/12/2014] [Indexed: 01/21/2023] Open
Abstract
Using A/J mice, which are susceptible to Staphylococcus aureus, we sought to identify genetic determinants of susceptibility to S. aureus, and evaluate their function with regard to S. aureus infection. One QTL region on chromosome 11 containing 422 genes was found to be significantly associated with susceptibility to S. aureus infection. Of these 422 genes, whole genome transcription profiling identified five genes (Dcaf7, Dusp3, Fam134c, Psme3, and Slc4a1) that were significantly differentially expressed in a) S. aureus -infected susceptible (A/J) vs. resistant (C57BL/6J) mice and b) humans with S. aureus blood stream infection vs. healthy subjects. Three of these genes (Dcaf7, Dusp3, and Psme3) were down-regulated in susceptible vs. resistant mice at both pre- and post-infection time points by qPCR. siRNA-mediated knockdown of Dusp3 and Psme3 induced significant increases of cytokine production in S. aureus-challenged RAW264.7 macrophages and bone marrow derived macrophages (BMDMs) through enhancing NF-κB signaling activity. Similar increases in cytokine production and NF-κB activity were also seen in BMDMs from CSS11 (C57BL/6J background with chromosome 11 from A/J), but not C57BL/6J. These findings suggest that Dusp3 and Psme3 contribute to S. aureus infection susceptibility in A/J mice and play a role in human S. aureus infection.
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Affiliation(s)
- Qin Yan
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Batu K. Sharma-Kuinkel
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Hitesh Deshmukh
- Division of Neonatology, Department of Pediatrics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Ephraim L. Tsalik
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Emergency Medicine Service, Durham Veteran's Affairs Medical Center, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Derek D. Cyr
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
| | - Joseph Lucas
- Quintiles Innovations, Morrisville, North Carolina, United States of America
| | - Christopher W. Woods
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Section on Infectious Diseases, Durham Veteran's Affairs Medical Center, Durham, North Carolina, United States of America
| | - William K. Scott
- Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States of America
- Dr. John T. Macdonald Foundation Department of Human Genetics, University of Miami Miller School of Medicine, Miami, Florida, United States of America
| | | | - Joshua Thaden
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
| | - Thomas H. Rude
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Sun Hee Ahn
- Department of Biochemistry School of Dentistry, Chonnam National University, Bukgu, Gwangju, Korea
| | - Vance G. Fowler
- Division of Infectious Diseases & International Health, Department of Medicine, Duke University School of Medicine, Durham, North Carolina, United States of America
- Duke Institute for Genome Sciences & Policy, Duke University, Durham, North Carolina, United States of America
- Duke Clinical Research Institute, Durham, North Carolina, United States of America
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Xiong S, Zheng Y, Jiang P, Liu R, Liu X, Qian J, Gu J, Chang L, Ge D, Chu Y. PA28gamma emerges as a novel functional target of tumour suppressor microRNA-7 in non-small-cell lung cancer. Br J Cancer 2013; 110:353-62. [PMID: 24281003 PMCID: PMC3899764 DOI: 10.1038/bjc.2013.728] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Revised: 09/12/2013] [Accepted: 10/23/2013] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND MicroRNA-7 (miR-7) has been reported to be a tumour suppressor gene. However, whether it has a role in the growth of non-small-cell lung cancer (NSCLC) and what is its target involved in the tumour growth is still under investigation. METHODS NSCLC tissue sample, NSCLC cell lines and tissue microarray were investigated in this study. Total RNA, miRNA and protein were used for RT-PCR and western blot analysis. Immunohistochemistry was performed in tissues microarray. Cell culture and intervention experiments were performed in vitro and in vivo. Bioinformatics prediction, western blot and luciferase assay were identified the target of miR-7. RESULTS In this study, we found that the expression of miR-7 was significantly downregulated not only in NSCLC cell lines, but also in human NSCLC tissues compared with the matched adjacent tissues. Restoration of its expression through miR-7 mimics in A549 and H1299 NSCLC cells inhibited cell proliferation, colony formation, and cell-cycle progression in vitro. More importantly, the tumorigenicity in nude mice was reduced after administration of miR-7 in vivo. In advance, through bioinformatic analysis, luciferase assay and western blot, we identified a novel target of miR-7, PA28gamma (a proteasome activator) to be enrolled in the regulation with tumour. PA28gamma mRNA and protein levels are markedly upregulated in NSCLC cell lines and tumour samples, exhibiting a strong inverse relation with that of miR-7. In addition, knockdown of PA28gamma induced similar effects as overexpression of miR-7 in NSCLC cells. Furthermore, miR-7 overexpression or silencing of PA28gamma reduced the cyclinD1 expression at mRNA and protein level in NSCLC cell lines. CONCLUSION All these findings strongly imply that the overexpression of PA28gamma resulted from miR-7 downexpression in NSCLC has an important role in promoting cancer cell progress and consequently results in NSCLC growth. Thus, strategies targeting PA28gamma and/or miR-7 may become promising molecular therapies in NSCLC treatment.
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Affiliation(s)
- S Xiong
- 1] Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China [2] Biotherapy Research Center of Fudan University, Shanghai, People's Republic of China [3] Department of Hematology/Oncology, The Second Hospital of Anhui Medical University, Hefei, Anhui, People's Republic of China
| | - Y Zheng
- 1] Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China [2] Biotherapy Research Center of Fudan University, Shanghai, People's Republic of China
| | - P Jiang
- Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - R Liu
- 1] Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China [2] Biotherapy Research Center of Fudan University, Shanghai, People's Republic of China
| | - X Liu
- Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - J Qian
- Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - J Gu
- Department of Thoracic Surgery, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - L Chang
- Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China
| | - D Ge
- Department of Thoracic Surgery, Zhongshan Hospital, Fudan University, Shanghai, People's Republic of China
| | - Y Chu
- 1] Department of Immunology and Key Laboratory of Molecular Medicine of Ministry of Education, Shanghai Medical College, Fudan University, Shanghai, People's Republic of China [2] Biotherapy Research Center of Fudan University, Shanghai, People's Republic of China
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El Khattabi I, Sharma A. Preventing p38 MAPK-mediated MafA degradation ameliorates β-cell dysfunction under oxidative stress. Mol Endocrinol 2013; 27:1078-90. [PMID: 23660596 PMCID: PMC3706838 DOI: 10.1210/me.2012-1346] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 04/30/2013] [Indexed: 12/19/2022] Open
Abstract
The reduction in the expression of glucose-responsive insulin gene transcription factor MafA accompanies the development of β-cell dysfunction under oxidative stress/diabetic milieu. Humans with type 2 diabetes have reduced MafA expression, and thus preventing this reduction could overcome β-cell dysfunction and diabetes. We previously showed that p38 MAPK, but not glycogen synthase kinase 3 (GSK3), is a major regulator of MafA degradation under oxidative stress. Here, we examined the mechanisms of this degradation and whether preventing MafA degradation under oxidative stress will overcome β-cell dysfunction. We show that under oxidative and nonoxidative conditions p38 MAPK directly binds to MafA and triggers MafA degradation via ubiquitin proteasomal pathway. However, unlike nonoxidative conditions, MafA degradation under oxidative stress depended on p38 MAPK-mediated phosphorylation at threonine (T) 134, and not T57. Furthermore the expression of alanine (A) 134-MafA, but not A57-MafA, reduced the oxidative stress-mediated loss of glucose-stimulated insulin secretion, which was independent of p38 MAPK action on protein kinase D, a regulator of insulin secretion. Interestingly, the expression of proteasomal activator PA28γ that degrades GSK3-phosphorylated (including T57) MafA was reduced under oxidative stress, explaining the dominance of p38 MAPK over the GSK3 pathway in regulating MafA stability under oxidative stress. These results identify two distinct pathways mediating p38 MAPK-dependent MafA degradation under oxidative and nonoxidative conditions and show that inhibiting MafA degradation under oxidative stress ameliorates β-cell dysfunction and could lead to novel therapies for diabetes.
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Affiliation(s)
- Ilham El Khattabi
- Section of Islet Cell and Regenerative Biology, Joslin Diabetes Center, Harvard Medical School, Boston, Massachusetts 02215, USA
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22
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Liu J, Wang Y, Li L, Zhou L, Wei H, Zhou Q, Liu J, Wang W, Ji L, Shan P, Wang Y, Yang Y, Jung SY, Zhang P, Wang C, Long W, Zhang B, Li X. Site-specific acetylation of the proteasome activator REGγ directs its heptameric structure and functions. J Biol Chem 2013; 288:16567-16578. [PMID: 23612972 PMCID: PMC3675592 DOI: 10.1074/jbc.m112.437129] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Revised: 04/22/2013] [Indexed: 12/22/2022] Open
Abstract
The proteasome activator REGγ has been reported to promote degradation of steroid receptor coactivator-3 and cyclin-dependent kinase inhibitors p21, p16, and p19 in a ubiquitin- and ATP-independent manner. A recent comparative analysis of REGγ expression in mouse and human tissues reveals a unique pattern of REGγ in specific cell types, suggesting undisclosed functions and biological importance of this molecule. Despite the emerging progress made in REGγ-related studies, how REGγ function is regulated remains to be explored. In this study, we report for the first time that REGγ can be acetylated mostly on its lysine 195 (Lys-195) residue by CREB binding protein (CBP), which can be reversed by sirtuin 1 (SIRT1) in mammalian cells. Site-directed mutagenesis abrogated acetylation at Lys-195 and significantly attenuated the capability of REGγ to degrade its target substrates, p21 and hepatitis C virus core protein. Mechanistically, acetylation at Lys-195 is important for the interactions between REGγ monomers and ultimately influences REGγ heptamerization. Biological analysis of cells containing REGγ-WT or REGγ-K195R mutant indicates an impact of acetylation on REGγ-mediated regulation of cell proliferation and cell cycle progression. These findings reveal a previously unknown mechanism in the regulation of REGγ assembly and activity, suggesting a potential venue for the intervention of the ubiquitin-independent REGγ proteasome activity.
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Affiliation(s)
- Jiang Liu
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China; Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 310036, China; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Ying Wang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China; Institute of Aging Research, School of Medicine, Hangzhou Normal University, Hangzhou, Zhejiang 310036, China; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Lei Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Li Zhou
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Haibin Wei
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Qingxia Zhou
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Jian Liu
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Weicang Wang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Lei Ji
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Peipei Shan
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Yan Wang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Yuanyuan Yang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Sung Yun Jung
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Pei Zhang
- Department of Pathology, the Second Chengdu Municipal Hospital, Chengdu, Sichuan 610017, China
| | - Chuangui Wang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China
| | - Weiwen Long
- Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030
| | - Bianhong Zhang
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China.
| | - Xiaotao Li
- Shanghai Key Laboratory of Regulatory Biology, Institute of Biomedical Sciences, School of Life Sciences, East China Normal University, Shanghai 200241, China; Department of Molecular and Cellular Biology, Baylor College of Medicine, Houston, Texas 77030.
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N-α-acetyltransferase 10 protein is a negative regulator of 28S proteasome through interaction with PA28β. FEBS Lett 2013; 587:1630-7. [PMID: 23624078 DOI: 10.1016/j.febslet.2013.04.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Revised: 03/10/2013] [Accepted: 04/02/2013] [Indexed: 01/10/2023]
Abstract
N-α-acetyltransferase 10 protein (Naa10p) regulates various pathways associated with cancer cell proliferation, metastasis, apoptosis and autophagy. However, its role in protein quality control is unknown. Here, we report that Naa10p is physically associated with proteasome activator 28β (PA28β). Naa10p also interacts with PA28α in a PA28β-dependent manner. Naa10p negatively regulates PA28-dependent chymotrypsin-like proteasome activity in cancer cells and in a cell-free system reconstituted with purified proteins, which is not related to 26S proteasome. Acetyltransferase activity of Naa10p is not required for its effect on chymotrypsin-like proteasome activity. Therefore, our data reveal that Naa10p suppresses 28S proteasome activity through interaction with PA28β.
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Lyupina YV, Abaturova SB, Erokhov PA, Orlova OV, Beljelarskaya SN, Mikhailov VS. Proteotoxic stress induced by Autographa californica nucleopolyhedrovirus infection of Spodoptera frugiperda Sf9 cells. Virology 2012; 436:49-58. [PMID: 23123012 DOI: 10.1016/j.virol.2012.10.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2012] [Revised: 10/02/2012] [Accepted: 10/09/2012] [Indexed: 11/19/2022]
Abstract
Baculovirus AcMNPV causes proteotoxicity in Sf9 cells as revealed by accumulation of ubiquitinated proteins and aggresomes in the course of infection. Inhibition of proteasomes by lactacystin increased markedly the stock of ubiquitinated proteins indicating a primary role of proteasomes in detoxication. The proteasomes were present in Sf9 cells as 26S and 20S complexes whose protease activity did not change during infection. Proteasome inhibition caused a delay in the initiation of viral DNA replication suggesting an important role of proteasomes at early stages in infection. However, lactacystin did not affect ongoing replication indicating that active proteasomes are not required for genome amplification. At late stages in infection (24-48 hpi), aggresomes containing the ubiquitinated proteins and HSP/HSC70s showed gradual fusion with the vacuole-like structures identified as lysosomes by antibody to cathepsin D. This result suggests that lysosomes may assist in protection against proteotoxicity caused by baculoviruses absorbing the ubiquitinated proteins.
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Affiliation(s)
- Yulia V Lyupina
- NK Koltzov Institute of Developmental Biology, Russian Academy of Sciences, Moscow 119334, Russia
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Abstract
The ubiquitin-proteasomal system is an essential element of the protein quality control machinery in cells. The central part of this system is the 20S proteasome. The proteasome is a barrel-shaped multienzyme complex, containing several active centers hidden at the inner surface of the hollow cylinder. So, the regulation of the substrate entry toward the inner proteasomal surface is a key control mechanism of the activity of this protease. This chapter outlines the knowledge on the structure of the subunits of the 20S proteasome, the binding and structure of some proteasomal regulators and inducible proteasomal subunits. Therefore, this chapter imparts the knowledge on proteasomal structure which is required for the understanding of the following chapters.
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