1
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Qi W, Bai J, Wang R, Zeng X, Zhang L. SATB1, senescence and senescence-related diseases. J Cell Physiol 2024; 239:e31327. [PMID: 38801120 DOI: 10.1002/jcp.31327] [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: 01/31/2024] [Revised: 05/06/2024] [Accepted: 05/15/2024] [Indexed: 05/29/2024]
Abstract
Aging leads to an accumulation of cellular mutations and damage, increasing the risk of senescence, apoptosis, and malignant transformation. Cellular senescence, which is pivotal in aging, acts as both a guard against cellular transformation and as a check against cancer progression. It is marked by stable cell cycle arrest, widespread macromolecular changes, a pro-inflammatory profile, and altered gene expression. However, it remains to be determined whether these differing subsets of senescent cells result from unique intrinsic programs or are influenced by their environmental contexts. Multiple transcription regulators and chromatin modifiers contribute to these alterations. Special AT-rich sequence-binding protein 1 (SATB1) stands out as a crucial regulator in this process, orchestrating gene expression by structuring chromatin into loop domains and anchoring DNA elements. This review provides an overview of cellular senescence and delves into the role of SATB1 in senescence-related diseases. It highlights SATB1's potential in developing antiaging and anticancer strategies, potentially contributing to improved quality of life and addressing aging-related diseases.
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Affiliation(s)
- Wenjing Qi
- Department of Bioscience, Changchun Normal University, Changchun, Jilin, China
- Key Laboratory of Molecular Epigenetics of Ministry of Education, College of Life Sciences, Northeast Normal University, Changchun, Jilin, China
| | - Jinping Bai
- Department of Bioscience, Changchun Normal University, Changchun, Jilin, China
| | - Ruoxi Wang
- Center for Cell Structure and Function, College of Life Sciences, Key Laboratory of Animal Resistance Biology of Shandong Province, Shandong Normal University, Jinan, Shandong, China
| | - Xianlu Zeng
- Key Laboratory of Molecular Epigenetics of Ministry of Education, College of Life Sciences, Northeast Normal University, Changchun, Jilin, China
| | - Lihui Zhang
- Department of Bioscience, Changchun Normal University, Changchun, Jilin, China
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2
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Alexander KD, Ramachandran S, Biswas K, Lambert CM, Russell J, Oliver DB, Armstrong W, Rettler M, Liu S, Doitsidou M, Bénard C, Walker AK, Francis MM. The homeodomain transcriptional regulator DVE-1 directs a program for synapse elimination during circuit remodeling. Nat Commun 2023; 14:7520. [PMID: 37980357 PMCID: PMC10657367 DOI: 10.1038/s41467-023-43281-4] [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: 11/10/2022] [Accepted: 11/02/2023] [Indexed: 11/20/2023] Open
Abstract
The elimination of synapses during circuit remodeling is critical for brain maturation; however, the molecular mechanisms directing synapse elimination and its timing remain elusive. We show that the transcriptional regulator DVE-1, which shares homology with special AT-rich sequence-binding (SATB) family members previously implicated in human neurodevelopmental disorders, directs the elimination of juvenile synaptic inputs onto remodeling C. elegans GABAergic neurons. Juvenile acetylcholine receptor clusters and apposing presynaptic sites are eliminated during the maturation of wild-type GABAergic neurons but persist into adulthood in dve-1 mutants, producing heightened motor connectivity. DVE-1 localization to GABAergic nuclei is required for synapse elimination, consistent with DVE-1 regulation of transcription. Pathway analysis of putative DVE-1 target genes, proteasome inhibitor, and genetic experiments implicate the ubiquitin-proteasome system in synapse elimination. Together, our findings define a previously unappreciated role for a SATB family member in directing synapse elimination during circuit remodeling, likely through transcriptional regulation of protein degradation processes.
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Affiliation(s)
- Kellianne D Alexander
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Shankar Ramachandran
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Kasturi Biswas
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Christopher M Lambert
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Julia Russell
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Devyn B Oliver
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - William Armstrong
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Monika Rettler
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Samuel Liu
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Maria Doitsidou
- Centre for Discovery Brain Sciences, University of Edinburgh, Edinburgh, Scotland
| | - Claire Bénard
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA
- Department of Biological Sciences, Université du Québec à Montréal, Quebec, Canada
| | - Amy K Walker
- Program in Molecular Medicine, University of Massachusetts Chan Medical School, Worcester, MA, USA
| | - Michael M Francis
- Department of Neurobiology, University of Massachusetts Chan Medical School, Worcester, MA, USA.
- Program in Neuroscience, University of Massachusetts Chan Medical School, Worcester, MA, USA.
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3
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Zelenka T, Papamatheakis DA, Tzerpos P, Panagopoulos G, Tsolis KC, Papadakis VM, Mariatos Metaxas D, Papadogkonas G, Mores E, Kapsetaki M, Papamatheakis J, Stanek D, Spilianakis C. A novel SATB1 protein isoform with different biophysical properties. Front Cell Dev Biol 2023; 11:1242481. [PMID: 37635874 PMCID: PMC10457122 DOI: 10.3389/fcell.2023.1242481] [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: 06/19/2023] [Accepted: 07/21/2023] [Indexed: 08/29/2023] Open
Abstract
Intra-thymic T cell development is coordinated by the regulatory actions of SATB1 genome organizer. In this report, we show that SATB1 is involved in the regulation of transcription and splicing, both of which displayed deregulation in Satb1 knockout murine thymocytes. More importantly, we characterized a novel SATB1 protein isoform and described its distinct biophysical behavior, implicating potential functional differences compared to the commonly studied isoform. SATB1 utilized its prion-like domains to transition through liquid-like states to aggregated structures. This behavior was dependent on protein concentration as well as phosphorylation and interaction with nuclear RNA. Notably, the long SATB1 isoform was more prone to aggregate following phase separation. Thus, the tight regulation of SATB1 isoforms expression levels alongside with protein post-translational modifications, are imperative for SATB1's mode of action in T cell development. Our data indicate that deregulation of these processes may also be linked to disorders such as cancer.
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Affiliation(s)
- Tomas Zelenka
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Dionysios-Alexandros Papamatheakis
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Petros Tzerpos
- Department of Biology, University of Crete, Heraklion, Crete, Greece
| | | | - Konstantinos C. Tsolis
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Vassilis M. Papadakis
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | | | - George Papadogkonas
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Eleftherios Mores
- Department of Biology, University of Crete, Heraklion, Crete, Greece
| | - Manouela Kapsetaki
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - Joseph Papamatheakis
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
| | - David Stanek
- Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czechia
| | - Charalampos Spilianakis
- Department of Biology, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology—Foundation for Research and Technology Hellas, Heraklion, Crete, Greece
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4
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Zhao Y, Zhou H, Zhao Y, Liang Z, Gong X, Yu J, Huang T, Yang C, Wu M, Xiao Y, Yang Y, Liu W, Wang X, Shu X, Bao J. BACE1 SUMOylation deregulates phosphorylation and ubiquitination in Alzheimer's disease pathology. J Neurochem 2023; 166:318-327. [PMID: 37286480 DOI: 10.1111/jnc.15870] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 05/10/2023] [Accepted: 05/15/2023] [Indexed: 06/09/2023]
Abstract
BACE1 is essential for the generation of amyloid-β (Aβ) that likely initiates the toxicity in Alzheimer's disease (AD). BACE1 activity is mainly regulated by post-translational modifications, but the relationship between these modifications is not fully characterized. Here, we studied the effects of BACE1 SUMOylation on its phosphorylation and ubiquitination. We demonstrate that SUMOylation of BACE1 inhibits its phosphorylation at S498 and its ubiquitination in vitro. Conversely, BACE1 phosphorylation at S498 suppresses its SUMOylation, which results in promoting BACE1 degradation in vitro. Furthermore, an increase in BACE1 SUMOylation is associated with the progression of AD pathology, while its phosphorylation and ubiquitination are decreased in an AD mouse model. Our findings suggest that BACE1 SUMOylation reciprocally influences its phosphorylation and competes against its ubiquitination, which might provide a new insight into the regulations of BACE1 activity and Aβ accumulation.
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Affiliation(s)
- Yanna Zhao
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Hongyan Zhou
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Yan Zhao
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
| | - Zhen Liang
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
| | - Xiaokang Gong
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
| | - Jing Yu
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Tiantian Huang
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Chaoqin Yang
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Mengjuan Wu
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Yifan Xiao
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Youhua Yang
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Physiology, School of Medicine, Jianghan University, Wuhan, China
| | - Wei Liu
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Xiaochuan Wang
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathophysiology, School of Basic Medicine, Key Laboratory of Education Ministry of China for Neurological Disorders, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiji Shu
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
| | - Jian Bao
- Institutes of Biomedical Sciences, School of Medicine, Jianghan University, Wuhan, China
- Department of Pathology and Pathophysiology, School of Medicine, Jianghan University, Wuhan, China
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5
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Hofmann S, Plank V, Groitl P, Skvorc N, Hofmann K, Luther J, Ko C, Zimmerman P, Bruss V, Stadler D, Carpentier A, Rezk S, Nassal M, Protzer U, Schreiner S. SUMO Modification of Hepatitis B Virus Core Mediates Nuclear Entry, Promyelocytic Leukemia Nuclear Body Association, and Efficient Formation of Covalently Closed Circular DNA. Microbiol Spectr 2023; 11:e0044623. [PMID: 37199632 PMCID: PMC10269885 DOI: 10.1128/spectrum.00446-23] [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: 02/05/2023] [Accepted: 04/24/2023] [Indexed: 05/19/2023] Open
Abstract
Persistence of hepatitis B virus (HBV) infection is due to a nuclear covalently closed circular DNA (cccDNA), generated from the virion-borne relaxed circular DNA (rcDNA) genome in a process likely involving numerous cell factors from the host DNA damage response (DDR). The HBV core protein mediates rcDNA transport to the nucleus and likely affects stability and transcriptional activity of cccDNA. Our study aimed at investigating the role of HBV core protein and its posttranslational modification (PTM) with SUMO (small ubiquitin-like modifiers) during the establishment of cccDNA. HBV core protein SUMO PTM was analyzed in His-SUMO-overexpressing cell lines. The impact of HBV core SUMOylation on association with cellular interaction partners and on the HBV life cycle was determined using SUMOylation-deficient mutants of the HBV core protein. Here, we show that the HBV core protein is posttranslationally modified by the addition of SUMO and that this modification impacts nuclear import of rcDNA. By using SUMOylation-deficient HBV core mutants, we show that SUMO modification is a prerequisite for the association with specific promyelocytic leukemia nuclear bodies (PML-NBs) and regulates the conversion of rcDNA to cccDNA. By in vitro SUMOylation of HBV core, we obtained evidence that SUMOylation triggers nucleocapsid disassembly, providing novel insights into the nuclear import process of rcDNA. HBV core protein SUMOylation and subsequent association with PML bodies in the nucleus constitute a key step in the conversion of HBV rcDNA to cccDNA and therefore a promising target for inhibiting formation of the HBV persistence reservoir. IMPORTANCE HBV cccDNA is formed from the incomplete rcDNA involving several host DDR proteins. The exact process and the site of cccDNA formation are poorly understood. Here, we show that HBV core protein SUMO modification is a novel PTM regulating the function of HBV core. A minor specific fraction of the HBV core protein resides with PML-NBs in the nuclear matrix. SUMO modification of HBV core protein mediates its recruitment to specific PML-NBs within the host cell. Within HBV nucleocapsids, SUMOylation of HBV core induces HBV capsid disassembly and is a prerequisite for nuclear entry of HBV core. SUMO HBV core protein association with PML-NBs is crucial for efficient conversion of rcDNA to cccDNA and for the establishment of the viral persistence reservoir. HBV core protein SUMO modification and the subsequent association with PML-NBs might constitute a potential novel target in the development of drugs targeting the cccDNA.
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Affiliation(s)
- Samuel Hofmann
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Verena Plank
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Peter Groitl
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Nathalie Skvorc
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
| | - Katharina Hofmann
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Julius Luther
- Institute of Virology, Hannover Medical School, Hannover, Germany
| | - Chunkyu Ko
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Peter Zimmerman
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Volker Bruss
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | - Daniela Stadler
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
| | | | - Shahinda Rezk
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Medical Research Institute, Department of Molecular and Diagnostic Microbiology, Alexandria University, Alexandria, Egypt
| | - Michael Nassal
- Department of Internal Medicine II/Molecular Biology, University Hospital Freiburg, Freiburg, Germany
| | - Ulrike Protzer
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
- German Center for Infection Research, Munich, Germany
| | - Sabrina Schreiner
- Institute of Virology, School of Medicine, Technical University of Munich, Germany
- Institute of Virology, Hannover Medical School, Hannover, Germany
- Institute of Virology, Helmholtz Zentrum München, Munich, Germany
- German Center for Infection Research, Munich, Germany
- Cluster of Excellence RESIST (Resolving Infection Susceptibility; EXC 2155), Hannover Medical School, Hannover, Germany
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6
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Linking nuclear matrix-localized PIAS1 to chromatin SUMOylation via direct binding of histones H3 and H2A.Z. J Biol Chem 2021; 297:101200. [PMID: 34537242 PMCID: PMC8496182 DOI: 10.1016/j.jbc.2021.101200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/25/2021] [Accepted: 08/25/2021] [Indexed: 12/02/2022] Open
Abstract
As a conserved posttranslational modification, SUMOylation has been shown to play important roles in chromatin-related biological processes including transcription. However, how the SUMOylation machinery associates with chromatin is not clear. Here, we present evidence that multiple SUMOylation machinery components, including SUMO E1 proteins SAE1 and SAE2 and the PIAS (protein inhibitor of activated STAT) family SUMO E3 ligases, are primarily associated with the nuclear matrix rather than with chromatin. We show using nuclease digestion that all PIAS family proteins maintain nuclear matrix association in the absence of chromatin. Of importance, we identify multiple histones including H3 and H2A.Z as directly interacting with PIAS1 and demonstrate that this interaction requires the PIAS1 SAP (SAF-A/B, Acinus, and PIAS) domain. We demonstrate that PIAS1 promotes SUMOylation of histones H3 and H2B in both a SAP domain– and an E3 ligase activity–dependent manner. Furthermore, we show that PIAS1 binds to heat shock–induced genes and represses their expression and that this function also requires the SAP domain. Altogether, our study reveals for the first time the nuclear matrix as the compartment most enriched in SUMO E1 and PIAS family E3 ligases. Our finding that PIAS1 interacts directly with histone proteins also suggests a molecular mechanism as to how nuclear matrix–associated PIAS1 is able to regulate transcription and other chromatin-related processes.
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7
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Abstract
The regulatory circuits that define developmental decisions of thymocytes are still incompletely resolved. SATB1 protein is predominantly expressed at the CD4+CD8+cell stage exerting its broad transcription regulation potential with both activatory and repressive roles. A series of post-translational modifications and the presence of potential SATB1 protein isoforms indicate the complexity of its regulatory potential. The most apparent mechanism of its involvement in gene expression regulation is via the orchestration of long-range chromatin loops between genes and their regulatory elements. Multiple SATB1 perturbations in mice uncovered a link to autoimmune diseases while clinical investigations on cancer research uncovered that SATB1 has a promoting role in several types of cancer and can be used as a prognostic biomarker. SATB1 is a multivalent tissue-specific factor with a broad and yet undetermined regulatory potential. Future investigations on this protein could further uncover T cell-specific regulatory pathways and link them to (patho)physiology.
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Affiliation(s)
- Tomas Zelenka
- Department of Biology, University of Crete , Heraklion, Crete, Greece.,Gene Regulation & Genomics, Institute of Molecular Biology and Biotechnology-Foundation for Research and Technology Hellas , Heraklion, Crete, Greece
| | - Charalampos Spilianakis
- Department of Biology, University of Crete , Heraklion, Crete, Greece.,Gene Regulation & Genomics, Institute of Molecular Biology and Biotechnology-Foundation for Research and Technology Hellas , Heraklion, Crete, Greece
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8
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Quantitative SUMO proteomics identifies PIAS1 substrates involved in cell migration and motility. Nat Commun 2020; 11:834. [PMID: 32047143 PMCID: PMC7012886 DOI: 10.1038/s41467-020-14581-w] [Citation(s) in RCA: 40] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Accepted: 01/07/2020] [Indexed: 01/09/2023] Open
Abstract
The protein inhibitor of activated STAT1 (PIAS1) is an E3 SUMO ligase that plays important roles in various cellular pathways. Increasing evidence shows that PIAS1 is overexpressed in various human malignancies, including prostate and lung cancers. Here we used quantitative SUMO proteomics to identify potential substrates of PIAS1 in a system-wide manner. We identified 983 SUMO sites on 544 proteins, of which 62 proteins were assigned as putative PIAS1 substrates. In particular, vimentin (VIM), a type III intermediate filament protein involved in cytoskeleton organization and cell motility, was SUMOylated by PIAS1 at Lys-439 and Lys-445 residues. VIM SUMOylation was necessary for its dynamic disassembly and cells expressing a non-SUMOylatable VIM mutant showed a reduced level of migration. Our approach not only enables the identification of E3 SUMO ligase substrates but also yields valuable biological insights into the unsuspected role of PIAS1 and VIM SUMOylation on cell motility. PIAS1 is an E3 SUMO ligase involved in various cellular processes. Here, the authors use quantitative proteomics to identify potential PIAS1 substrates in human cells and elucidate the biological consequences of PIAS1-mediated SUMOylation of vimentin.
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9
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SATB family chromatin organizers as master regulators of tumor progression. Oncogene 2018; 38:1989-2004. [PMID: 30413763 DOI: 10.1038/s41388-018-0541-4] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/30/2018] [Accepted: 09/02/2018] [Indexed: 02/07/2023]
Abstract
SATB (Special AT-rich binding protein) family proteins have emerged as key regulators that integrate higher-order chromatin organization with the regulation of gene expression. Studies over the past decade have elucidated the specific roles of SATB1 and SATB2, two closely related members of this family, in cancer progression. SATB family chromatin organizers play diverse and important roles in regulating the dynamic equilibrium of apoptosis, cell invasion, metastasis, proliferation, angiogenesis, and immune modulation. This review highlights cellular and molecular events governed by SATB1 influencing the structural organization of chromatin and interacting with several co-activators and co-repressors of transcription towards tumor progression. SATB1 expression across tumor cell types generates cellular and molecular heterogeneity culminating in tumor relapse and metastasis. SATB1 exhibits dynamic expression within intratumoral cell types regulated by the tumor microenvironment, which culminates towards tumor progression. Recent studies suggested that cell-specific expression of SATB1 across tumor recruited dendritic cells (DC), cytotoxic T lymphocytes (CTL), T regulatory cells (Tregs) and tumor epithelial cells along with tumor microenvironment act as primary determinants of tumor progression and tumor inflammation. In contrast, SATB2 is differentially expressed in an array of cancer types and is involved in tumorigenesis. Survival analysis for patients across an array of cancer types correlated with expression of SATB family chromatin organizers suggested tissue-specific expression of SATB1 and SATB2 contributing to disease prognosis. In this context, it is pertinent to understand molecular players, cellular pathways, genetic and epigenetic mechanisms governed by cell types within tumors regulated by SATB proteins. We propose that patient survival analysis based on the expression profile of SATB chromatin organizers would facilitate their unequivocal establishment as prognostic markers and therapeutic targets for cancer therapy.
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Rao H, Bai Y, Li Q, Zhuang B, Yuan Y, Liu Y, Peng W, Baker PN, Tong C, Luo X, Qi H. SATB1 downregulation induced by oxidative stress participates in trophoblast invasion by regulating β-catenin†. Biol Reprod 2018; 98:810-820. [PMID: 29546272 DOI: 10.1093/biolre/ioy033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 03/08/2018] [Indexed: 12/27/2022] Open
Affiliation(s)
- Haiying Rao
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Yuxiang Bai
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Qingshu Li
- Department of Pathology, Chongqing Medical University, Chongqing, China
| | - Baimei Zhuang
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Yu Yuan
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Yamin Liu
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Wei Peng
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Philip N Baker
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
- Liggins Institute, University of Auckland, Auckland, New Zealand
| | - Chao Tong
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Xin Luo
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
| | - Hongbo Qi
- Department of Obstetrics and Gynecology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- Canada–China–New Zealand Joint Laboratory of Maternal and Fetal Medicine, Chongqing Medical University, China
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11
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The Special AT-rich Sequence Binding Protein 1 (SATB1) and its role in solid tumors. Cancer Lett 2018; 417:96-111. [DOI: 10.1016/j.canlet.2017.12.031] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/19/2017] [Accepted: 12/21/2017] [Indexed: 02/07/2023]
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12
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Dustrude ET, Perez-Miller S, François-Moutal L, Moutal A, Khanna M, Khanna R. A single structurally conserved SUMOylation site in CRMP2 controls NaV1.7 function. Channels (Austin) 2017; 11:316-328. [PMID: 28277940 DOI: 10.1080/19336950.2017.1299838] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
The neuronal collapsin response mediator protein 2 (CRMP2) undergoes several posttranslational modifications that codify its functions. Most recently, CRMP2 SUMOylation (addition of small ubiquitin like modifier (SUMO)) was identified as a key regulatory step within a modification program that codes for CRMP2 interaction with, and trafficking of, voltage-gated sodium channel NaV1.7. In this paper, we illustrate the utility of combining sequence alignment within protein families with structural analysis to identify, from several putative SUMOylation sites, those that are most likely to be biologically relevant. Co-opting this principle to CRMP2, we demonstrate that, of 3 sites predicted to be SUMOylated in CRMP2, only the lysine 374 site is a SUMOylation client. A reduction in NaV1.7 currents was the corollary of the loss of CRMP2 SUMOylation at this site. A 1.78-Å-resolution crystal structure of mouse CRMP2 was solved using X-ray crystallography, revealing lysine 374 as buried within the CRMP2 tetramer interface but exposed in the monomer. Since CRMP2 SUMOylation is dependent on phosphorylation, we postulate that this state forces CRMP2 toward a monomer, exposing the SUMO site and consequently, resulting in constitutive regulation of NaV1.7.
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Affiliation(s)
- Erik Thomas Dustrude
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA
| | - Samantha Perez-Miller
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA
| | - Liberty François-Moutal
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA
| | - Aubin Moutal
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA
| | - May Khanna
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA
| | - Rajesh Khanna
- a Department of Pharmacology, College of Medicine , University of Arizona , Tucson , AZ , USA.,b Department of Anesthesiology, College of Medicine , University of Arizona , Tucson , AZ , USA.,c Neuroscience Graduate Interdisciplinary Program, College of Medicine , University of Arizona , Tucson , AZ , USA
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13
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Li YC, Bu LL, Mao L, Ma SR, Liu JF, Yu GT, Deng WW, Zhang WF, Sun ZJ. SATB1 promotes tumor metastasis and invasiveness in oral squamous cell carcinoma. Oral Dis 2016; 23:247-254. [PMID: 27783844 DOI: 10.1111/odi.12602] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 10/09/2016] [Accepted: 10/20/2016] [Indexed: 12/31/2022]
Abstract
OBJECTIVE Our aim is to evaluate the expression of SATB1 in human oral squamous cell carcinomas (OSCC) and its role in the invasiveness and metastasis of OSCC. SUBJECTS AND METHODS A human OSCC tissue microarray was used to evaluate the expression pattern of SATB1. SATB1 mRNA knockdown was performed in human OSCC cell lines SCC25 and Cal27 to assess the function of SATB1 in the invasiveness and metastasis of OSCC. RESULTS SATB1 is highly expressed in human OSCC determined by immunohistochemistry, and its nuclear/cytoplasmic ratio of histoscore is significantly correlated with patients' prognosis. Reduced cell motility, invasiveness, expression of epithelial to mesenchymal transition (EMT) markers (N-cadherin and β-catenin), and elevated expression of epithelial markers were observed in SATB1-knockdown cells in in vitro studies. Depletion of SATB1 also restored a cobblestone-like morphology in TGF-β1-treated cells. CONCLUSIONS These findings suggest SATB1 may play an important role in OSCC invasiveness and metastasis.
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Affiliation(s)
- Y-C Li
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - L-L Bu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral and Maxillofacial-Head and Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - L Mao
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - S-R Ma
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - J-F Liu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - G-T Yu
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - W-W Deng
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China
| | - W-F Zhang
- Department of Oral and Maxillofacial-Head and Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
| | - Z-J Sun
- The State Key Laboratory Breeding Base of Basic Science of Stomatology & Key Laboratory of Oral Biomedicine Ministry of Education, School & Hospital of Stomatology, Wuhan University, Wuhan, China.,Department of Oral and Maxillofacial-Head and Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
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14
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Meng F, Qian J, Yue H, Li X, Xue K. SUMOylation of Rb enhances its binding with CDK2 and phosphorylation at early G1 phase. Cell Cycle 2016; 15:1724-32. [PMID: 27163259 PMCID: PMC4957593 DOI: 10.1080/15384101.2016.1182267] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Retinoblastoma protein (Rb) is a prototypical tumor suppressor that is vital to the negative regulation of the cell cycle and tumor progression. Hypo-phosphorylated Rb is associated with G0/G1 arrest by suppressing E2F transcription factor activity, whereas Rb hyper-phosphorylation allows E2F release and cell cycle progression from G0/G1 to S phase. However, the factors that regulate cyclin-dependent protein kinase (CDK)-dependent hyper-phosphorylation of Rb during the cell cycle remain obscure. In this study, we show that throughout the cell cycle, Rb is specifically small ubiquitin-like modifier (SUMO)ylated at early G1 phase. SUMOylation of Rb stimulates its phosphorylation level by recruiting a SUMO-interaction motif (SIM)-containing kinase CDK2, leading to Rb hyper-phosphorylation and E2F-1 release. In contrast, a SUMO-deficient Rb mutant results in reduced SUMOylation and phosphorylation, weakened CDK2 binding, and attenuated E2F-1 sequestration. Furthermore, we reveal that Rb SUMOylation is required for cell proliferation. Therefore, our study describes a novel mechanism that regulates Rb phosphorylation during cell cycle progression.
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Affiliation(s)
- Fengxi Meng
- a Department of Ophthalmology , Eye and ENT Hospital of Fudan University , Shanghai , China.,b Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University , Shanghai , China
| | - Jiang Qian
- a Department of Ophthalmology , Eye and ENT Hospital of Fudan University , Shanghai , China.,b Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University , Shanghai , China
| | - Han Yue
- a Department of Ophthalmology , Eye and ENT Hospital of Fudan University , Shanghai , China.,b Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University , Shanghai , China
| | - Xiaofeng Li
- a Department of Ophthalmology , Eye and ENT Hospital of Fudan University , Shanghai , China.,b Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University , Shanghai , China
| | - Kang Xue
- a Department of Ophthalmology , Eye and ENT Hospital of Fudan University , Shanghai , China.,b Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University , Shanghai , China
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15
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Yang YQ, Li H, Zhang XS, Li W, Huang LT, Yu Z, Jiang TW, Chen Q, Hang CH. Inhibition of SENP3 by lentivirus induces suppression of apoptosis in experimental subarachnoid hemorrhage in rats. Brain Res 2015; 1622:270-8. [PMID: 26151898 DOI: 10.1016/j.brainres.2015.06.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 06/06/2015] [Accepted: 06/23/2015] [Indexed: 12/20/2022]
Abstract
BACKGROUND Subarachnoid hemorrhage (SAH) is one of the life-threatening diseases with high morbidity and mortality rates. SUMO-specific proteases 3 (SENP3), a member of the small ubiquitin-like modifier specific protease family, was identified as an isopeptidase that deconjugates SUMOylation (The covalent modification by SUMO) of modified protein substrates. It is reported that SUMO-2/3 conjugation, a member of SUMOylation, presented neuroprotection. The study aimed to evaluate the expression of SENP3 and to explore its potential role in SAH. MATERIALS AND METHODS A total of 108 Sprague Dawley (SD) rats were randomly divided into 2 parts experiment and 9 subgroups (part 1:Sham group, SAH group, SAH+NAC group, SAH+vehicle group; part 2: Sham group, SAH group, SAH+lv-SENP3 group, SAH+lv-null group, SAH+NS group). 7 days before SAH, lentivirus was administrated into rats׳ left lateral ventricle to down-regulate SENP3. Experimental SAH was imitated by injection with 0.3ml nonheparinized autoblood into the prechiasmatic cistern. MDA levels, SOD activities, and GSH contents were detected to evaluate oxidative stress level. SENP3 and cleaved caspase 3 were detected by western blot, apoptosis was observed by TUNEL staining. RESULTS High oxidative stress level following SAH induced rising of SENP3. And inhibition of SENP3 by lentivirus induces suppression of apoptosis in experimental subarachnoid hemorrhage in rats. CONCLUSION When SENP3 accumulated by high oxidative stress, caspase 3 activated subsequently. And it leads to more severe apoptosis than physiological.
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Affiliation(s)
- Yi-Qing Yang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Hua Li
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Xiang-Sheng Zhang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Wei Li
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Li-Tian Huang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Southern Medical University, Guangzhou, China
| | - Zhuang Yu
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Tian-Wei Jiang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China
| | - Qiang Chen
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Southern Medical University, Guangzhou, China
| | - Chun-Hua Hang
- Department of Neurosurgery, Jinling Hospital, School of Medicine, Nanjing University, Nanjing, Jiangsu Province, China.
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16
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Borghesi L. Hematopoiesis in steady-state versus stress: self-renewal, lineage fate choice, and the conversion of danger signals into cytokine signals in hematopoietic stem cells. THE JOURNAL OF IMMUNOLOGY 2014; 193:2053-8. [PMID: 25128551 DOI: 10.4049/jimmunol.1400936] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Long-term hematopoietic stem cells (LT-HSCs) replenish the innate and adaptive immune compartments throughout life. Although significant progress has defined the major transcription factors that regulate lineage specification, the architectural proteins that globally coordinate DNA methylation, histone modification, and changes in gene expression are poorly defined. Provocative new studies establish the chromatin organizer special AT-rich binding protein 1 (Satb1) as one such global regulator in LT-HSCs. Satb1 is a nuclear organizer that partitions chromatin through the formation of cage-like structures. By integrating epigenetic and transcriptional pathways, Satb1 coordinates LT-HSC division, self-renewal, and lymphoid potential. Unexpected among the assortment of genes under Satb1 control in hematopoietic stem cells (HSCs) are cytokines, a finding that takes on additional importance with the provocative finding that short-term HSCs and downstream multipotent progenitors are potent and biologically relevant cytokine secretors during stress-mediated hematopoiesis. Together, these studies reveal a new mechanism of fate regulation and an unforeseen functional capability of HSCs.
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Affiliation(s)
- Lisa Borghesi
- Department of Immunology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
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17
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Yang YQ, Li H, Zhang X, Wang CX, Sun Q, Li S, Li W, Li W, Ding K, Liu M, Yu Z, Hang CH. Expression and Cell Distribution of SENP3 in the Cerebral Cortex After Experimental Subarachnoid Hemorrhage in Rats: A Pilot Study. Cell Mol Neurobiol 2014; 35:407-416. [DOI: 10.1007/s10571-014-0136-8] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 11/03/2014] [Indexed: 10/24/2022]
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18
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Engelke H, Chou C, Uprety R, Jess P, Deiters A. Control of protein function through optochemical translocation. ACS Synth Biol 2014; 3:731-6. [PMID: 24933258 PMCID: PMC4210160 DOI: 10.1021/sb400192a] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
![]()
Controlled manipulation of proteins
and their function is important
in almost all biological disciplines. Here, we demonstrate control
of protein activity with light. We present two different applications—light-triggered
transcription and light-triggered protease cleavage—both based
on the same concept of protein mislocation, followed by optochemically
triggered translocation to an active cellular compartment. In our
approach, we genetically encode a photocaged lysine into the nuclear
localization signal (NLS) of the transcription factor SATB1. This
blocks nuclear import of the protein until illumination induces caging
group removal and release of the protein into the nucleus. In the
first application, prepending this NLS to the transcription factor
FOXO3 allows us to optochemically switch on its transcription activity.
The second application uses the developed light-activated NLS to control
nuclear import of TEV protease and subsequent cleavage of nuclear
proteins containing TEV cleavage sites. The small size of the light-controlled
NLS (only 20 amino acids) minimizes impact of its insertion on protein
function and promises a general approach to a wide range of optochemical
applications. Since the light-activated NLS is genetically encoded
and optically triggered, it will prove useful to address a variety
of problems requiring spatial and temporal control of protein function,
for example, in stem-cell, developmental, and cancer biology.
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Affiliation(s)
- Hanna Engelke
- Department
of Chemistry and Center for NanoScience (CeNS), University of Munich (LMU), Butenandtstraße 11, 81377 München, Germany
| | - Chungjung Chou
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Rajendra Uprety
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
| | - Phillip Jess
- Department
of Physics and MCB, University of California, Berkeley, California 94720, United States
| | - Alexander Deiters
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695, United States
- Department
of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
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19
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Henley JM, Craig TJ, Wilkinson KA. Neuronal SUMOylation: mechanisms, physiology, and roles in neuronal dysfunction. Physiol Rev 2014; 94:1249-85. [PMID: 25287864 PMCID: PMC4187031 DOI: 10.1152/physrev.00008.2014] [Citation(s) in RCA: 135] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Protein SUMOylation is a critically important posttranslational protein modification that participates in nearly all aspects of cellular physiology. In the nearly 20 years since its discovery, SUMOylation has emerged as a major regulator of nuclear function, and more recently, it has become clear that SUMOylation has key roles in the regulation of protein trafficking and function outside of the nucleus. In neurons, SUMOylation participates in cellular processes ranging from neuronal differentiation and control of synapse formation to regulation of synaptic transmission and cell survival. It is a highly dynamic and usually transient modification that enhances or hinders interactions between proteins, and its consequences are extremely diverse. Hundreds of different proteins are SUMO substrates, and dysfunction of protein SUMOylation is implicated in a many different diseases. Here we briefly outline core aspects of the SUMO system and provide a detailed overview of the current understanding of the roles of SUMOylation in healthy and diseased neurons.
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Affiliation(s)
- Jeremy M Henley
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Tim J Craig
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
| | - Kevin A Wilkinson
- School of Biochemistry, University of Bristol, Bristol, United Kingdom
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20
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Wang Z, Yang X, Guo S, Yang Y, Su XC, Shen Y, Long J. Crystal structure of the ubiquitin-like domain-CUT repeat-like tandem of special AT-rich sequence binding protein 1 (SATB1) reveals a coordinating DNA-binding mechanism. J Biol Chem 2014; 289:27376-85. [PMID: 25124042 DOI: 10.1074/jbc.m114.562314] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
SATB1 is essential for T-cell development and growth and metastasis of multitype tumors and acts as a global chromatin organizer and gene expression regulator. The DNA binding ability of SATB1 plays vital roles in its various biological functions. We report the crystal structure of the N-terminal module of SATB1. Interestingly, this module contains a ubiquitin-like domain (ULD) and a CUT repeat-like (CUTL) domain (ULD-CUTL tandem). Detailed biochemical experiments indicate that the N terminus of SATB1 (residues 1-248, SATB1((1-248))), including the extreme 70 N-terminal amino acids, and the ULD-CUTL tandem bind specifically to DNA targets. Our results show that the DNA binding ability of full-length SATB1 requires the contribution of the CUTL domain, as well as the CUT1-CUT2 tandem domain and the homeodomain. These findings may reveal a multiple-domain-coordinated mechanism whereby SATB1 recognizes DNA targets.
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Affiliation(s)
- Zheng Wang
- From the State Key Laboratory of Medicinal Chemical Biology, the College of Life Sciences, and
| | - Xue Yang
- From the State Key Laboratory of Medicinal Chemical Biology, the College of Life Sciences, and
| | - Shuang Guo
- From the State Key Laboratory of Medicinal Chemical Biology
| | - Yin Yang
- the State Key Laboratory of Elemento-organic Chemistry, Nankai University and
| | - Xun-Cheng Su
- the State Key Laboratory of Elemento-organic Chemistry, Nankai University and
| | - Yuequan Shen
- From the State Key Laboratory of Medicinal Chemical Biology, the College of Life Sciences, and the Synergetic Innovation Center of Chemical Science and Engineering, Tianjin 300071, China
| | - Jiafu Long
- From the State Key Laboratory of Medicinal Chemical Biology, the College of Life Sciences, and
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21
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Fluorosed mouse ameloblasts have increased SATB1 retention and Gαq activity. PLoS One 2014; 9:e103994. [PMID: 25090413 PMCID: PMC4121220 DOI: 10.1371/journal.pone.0103994] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Accepted: 07/06/2014] [Indexed: 02/05/2023] Open
Abstract
Dental fluorosis is characterized by subsurface hypomineralization and increased porosity of enamel, associated with a delay in the removal of enamel matrix proteins. To investigate the effects of fluoride on ameloblasts, A/J mice were given 50 ppm sodium fluoride in drinking water for four weeks, resulting serum fluoride levels of 4.5 µM, a four-fold increase over control mice with no fluoride added to drinking water. MicroCT analyses showed delayed and incomplete mineralization of fluorosed incisor enamel as compared to control enamel. A microarray analysis of secretory and maturation stage ameloblasts microdissected from control and fluorosed mouse incisors showed that genes clustered with Mmp20 appeared to be less downregulated in maturation stage ameloblasts of fluorosed incisors as compared to control maturation ameloblasts. One of these Mmp20 co-regulated genes was the global chromatin organizer, special AT-rich sequence-binding protein-1 (SATB1). Immunohistochemical analysis showed increased SATB1 protein present in fluorosed ameloblasts compared to controls. In vitro, exposure of human ameloblast-lineage cells to micromolar levels of both NaF and AlF3 led to a significantly increase in SATB1 protein content, but not levels of Satb1 mRNA, suggesting a fluoride-induced mechanism protecting SABT1 from degradation. Consistent with this possibility, we used immunohistochemistry and Western blot to show that fluoride exposed ameloblasts had increased phosphorylated PKCα both in vivo and in vitro. This kinase is known to phosphorylate SATB1, and phosphorylation is known to protect SATB1 from degradation by caspase-6. In addition, production of cellular diacylglycerol (DAG) was significantly increased in fluorosed ameloblasts, suggesting that the increased phosphorylation of SATB1 may be related to an effect of fluoride to enhance Gαq activity of secretory ameloblasts.
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22
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Abstract
Posttranslational modification with small ubiquitin-related modifier (SUMO) proteins is now established as one of the key regulatory protein modifications in eukaryotic cells. Hundreds of proteins involved in processes such as chromatin organization, transcription, DNA repair, macromolecular assembly, protein homeostasis, trafficking, and signal transduction are subject to reversible sumoylation. Hence, it is not surprising that disease links are beginning to emerge and that interference with sumoylation is being considered for intervention. Here, we summarize basic mechanisms and highlight recent developments in the physiology of sumoylation.
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Affiliation(s)
- Annette Flotho
- Zentrum für Molekulare Biologie der Universität Heidelberg, DKFZ-ZMBH, Heidelberg D-69120, Germany.
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23
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Phosphorylated SATB1 is associated with the progression and prognosis of glioma. Cell Death Dis 2013; 4:e901. [PMID: 24176859 PMCID: PMC3920943 DOI: 10.1038/cddis.2013.433] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2013] [Revised: 09/17/2013] [Accepted: 10/02/2013] [Indexed: 02/07/2023]
Abstract
Special AT-rich sequence-binding protein 1 (SATB1) is a global chromatin organizer and gene regulator, and high expression of SATB1 is associated with progression and poor prognosis in several malignancies. Here, we examine the expression pattern of SATB1 in glioma. Microarray analysis of 127 clinical samples showed that SATB1 mRNA was expressed at lower levels in highly malignant glioblastoma multiforme (GBM) than in low-grade glioma and normal brain tissue. This result was further confirmed by real-time RT-PCR in the clinical samples, three GBM cell lines, primary SU3 glioma cells and tumor cells harvested by laser-capture microdissection. Consistent with the mRNA levels, SATB1 protein expression was downregulated in high-grade glioma, as shown by western blotting. However, phospho-SATB1 levels showed an opposite pattern, with a significant increase in these tumors. Immunohistochemical analysis of phospho-SATB1 expression in tissue microarrays with tumors from 122 glioma cases showed that phospho-SATB1 expression was significantly associated with high histological grade and poor survival by Kaplan–Meier analysis. In vitro transfection analysis showed that phospho-SATB1 DNA binding has a key role in regulating the proliferation and invasion of glioma cells. The effect of SATB1 in glioma cell is mainly histone deacetylase (HDAC1)-dependent. We conclude that phospho-SATB1, but not SATB1 mRNA expression, is associated with the progression and prognosis of glioma. By interaction with HDAC1, phospho-SATB1 contributes to the invasive and proliferative phenotype of GBM cells.
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24
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Roux PP, Thibault P. The coming of age of phosphoproteomics--from large data sets to inference of protein functions. Mol Cell Proteomics 2013; 12:3453-64. [PMID: 24037665 DOI: 10.1074/mcp.r113.032862] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Protein phosphorylation is one of the most common post-translational modifications used in signal transduction to control cell growth, proliferation, and survival in response to both intracellular and extracellular stimuli. This modification is finely coordinated by a network of kinases and phosphatases that recognize unique sequence motifs and/or mediate their functions through scaffold and adaptor proteins. Detailed information on the nature of kinase substrates and site-specific phosphoregulation is required in order for one to better understand their pathophysiological roles. Recent advances in affinity chromatography and mass spectrometry (MS) sensitivity have enabled the large-scale identification and profiling of protein phosphorylation, but appropriate follow-up experiments are required in order to ascertain the functional significance of identified phosphorylation sites. In this review, we present meaningful technical details for MS-based phosphoproteomic analyses and describe important considerations for the selection of model systems and the functional characterization of identified phosphorylation sites.
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Affiliation(s)
- Philippe P Roux
- Institute for Research in Immunology and Cancer, Université de Montréal, P.O. Box 6128, Station. Centre-ville, Montréal, Québec H3C 3J7, Canada
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25
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An upregulation of SENP3 after spinal cord injury: implications for neuronal apoptosis. Neurochem Res 2012; 37:2758-66. [PMID: 23054070 DOI: 10.1007/s11064-012-0869-z] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2012] [Revised: 07/20/2012] [Accepted: 08/03/2012] [Indexed: 01/15/2023]
Abstract
SENP3 (SUMO-specific proteases 3), a member of the small ubiquitin-like modifier specific protease family, was identified as a molecule that deconjugates SUMOylation of modified protein substrates and functions as an isopeptidase by disrupting SUMO homeostasis to facilitate cancer development and progression. However, its expression and function in nervous system injury and repair are still unclear. In this study, we employed an acute spinal cord injury (SCI) model in adult rats and investigated the dynamic changes of SENP3 expression in the spinal cord. Western blot analysis indicated a gradual increase in SENP3 expression, which peaked 3 days after SCI, and then declined over the following days. Immunohistochemistry results further confirmed that SENP3 was expressed at low levels in the gray and white matter in the non-injured condition and increased after SCI. Moreover, immunofluorescence double-labeling showed that SENP3 was co-expressed with the neuronal marker, NeuN. Furthermore, the SENP3-positive cells that were co-expressed with NeuN had also expressed active caspase-3 after injury. To investigate whether SENP3 plays a role in neuronal apoptosis, we applied H(2)O(2) to induce neuronal apoptosis in vitro. Western blot analysis showed a significant upregulation of SENP3 and active caspase-3 following H(2)O(2) stimulation. Taken together, these results suggest that SENP3 may play important roles in the pathophysiology of SCI.
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26
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Chromatin organizer SATB1 is an important determinant of T-cell differentiation. Immunol Cell Biol 2012; 90:852-9. [PMID: 22710879 DOI: 10.1038/icb.2012.28] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
T-cell development and differentiation is coordinated by a multitude of signaling molecules and transcription factors that impart distinct functional properties to progenitors. In this review, we focus on the role of the T lineage-enriched chromatin organizer and regulator SATB1 in T-cell differentiation. SATB1 mediates Wnt signaling by recruiting β-catenin to its genomic targets and coordinates T helper type 2 (T(H)2) differentiation by positively regulating GATA-3. In contrast, maintenance of regulatory T cell (Treg) functions are dependent on inhibition of SATB1-mediated modulation of global chromatin organization. We discuss how regulation of the activity of SATB1 has a critical role in driving these two important differentiation pathways in T cells.
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Barboro P, Repaci E, D’Arrigo C, Balbi C. The role of nuclear matrix proteins binding to matrix attachment regions (Mars) in prostate cancer cell differentiation. PLoS One 2012; 7:e40617. [PMID: 22808207 PMCID: PMC3394767 DOI: 10.1371/journal.pone.0040617] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2011] [Accepted: 06/11/2012] [Indexed: 11/19/2022] Open
Abstract
In tumor progression definite alterations in nuclear matrix (NM) protein composition as well as in chromatin structure occur. The NM interacts with chromatin via specialized DNA sequences called matrix attachment regions (MARs). In the present study, using a proteomic approach along with a two-dimensional Southwestern assay and confocal laser microscopy, we show that the differentiation of stabilized human prostate carcinoma cells is marked out by modifications both NM protein composition and bond between NM proteins and MARs. Well-differentiated androgen-responsive and slowly growing LNCaP cells are characterized by a less complex pattern and by a major number of proteins binding MAR sequences in comparison to 22Rv1 cells expressing androgen receptor but androgen-independent. Finally, in the poorly differentiated and strongly aggressive androgen-independent PC3 cells the complexity of NM pattern further increases and a minor number of proteins bind the MARs. Furthermore, in this cell line with respect to LNCaP cells, these changes are synchronous with modifications in both the nuclear distribution of the MAR sequences and in the average loop dimensions that significantly increase. Although the expression of many NM proteins changes during dedifferentiation, only a very limited group of MAR-binding proteins seem to play a key role in this process. Variations in the expression of poly (ADP-ribose) polymerase (PARP) and special AT-rich sequence-binding protein-1 (SATB1) along with an increase in the phosphorylation of lamin B represent changes that might trigger passage towards a more aggressive phenotype. These results suggest that elucidating the MAR-binding proteins that are involved in the differentiation of prostate cancer cells could be an important tool to improve our understanding of this carcinogenesis process, and they could also be novel targets for prostate cancer therapy.
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Affiliation(s)
- Paola Barboro
- IRCCS Azienda Ospedaliera Universitaria San Martino IST-Istituto Nazionale per la Ricerca sul Cancro, Department of Diagnostic Technologies, Genoa, Italy
| | - Erica Repaci
- IRCCS Azienda Ospedaliera Universitaria San Martino IST-Istituto Nazionale per la Ricerca sul Cancro, Department of Diagnostic Technologies, Genoa, Italy
| | - Cristina D’Arrigo
- C.N.R., Istituto per lo Studio delle Macromolecole, ISMAC, Sezione di Genova, Genoa, Italy
| | - Cecilia Balbi
- IRCCS Azienda Ospedaliera Universitaria San Martino IST-Istituto Nazionale per la Ricerca sul Cancro, Department of Diagnostic Technologies, Genoa, Italy
- * E-mail:
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Wimmer P, Blanchette P, Schreiner S, Ching W, Groitl P, Berscheminski J, Branton PE, Will H, Dobner T. Cross-talk between phosphorylation and SUMOylation regulates transforming activities of an adenoviral oncoprotein. Oncogene 2012; 32:1626-37. [PMID: 22614022 DOI: 10.1038/onc.2012.187] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Since the discovery of post-translational modification (PTM) by the small ubiquitin-related modifiers (SUMOs), a multitude of proteins have been described to be reversibly modified, resulting in the alteration of several cellular pathways. Interestingly, various pathogens gain access to this modification system, although the molecular mechanisms and functional consequences are barely understood. We show here that the adenoviral oncoprotein E1B-55K is a substrate of the SUMO conjugation system, which is directly linked to its C-terminal phosphorylation. This regulative connection is indispensable for modulation of the tumor suppressor p53/chromatin-remodeling factor Daxx by E1B-55K and, consequently, its oncogenic potential in primary mammalian cells. In virus infection, E1B-55K PTMs are necessary for localization to viral transcription/replication sites. Furthermore, we identify the E2 enzyme Ubc9 as an interaction partner of E1B-55K, providing a possible molecular explanation for SUMO-dependent modulation of cellular target proteins. In conclusion, these results for the first time provide evidence how E1B-55K PTMs are regulated and subsequently facilitate exploitation of the host cell SUMOylation machinery.
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Affiliation(s)
- P Wimmer
- Department of Molecular Virology, Heinrich-Pette-Institute-Leibniz-Institute for Experimental Virology, Hamburg, Germany
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Wu Y, Wang L, Zhou P, Wang G, Zeng Y, Wang Y, Liu J, Zhang B, Liu S, Luo H, Li X. Regulation of REGγ cellular distribution and function by SUMO modification. Cell Res 2011; 21:807-16. [PMID: 21445096 DOI: 10.1038/cr.2011.57] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Discovery of emerging REGγ-regulated proteins has accentuated the REGγ-proteasome as an important pathway in multiple biological processes, including cell growth, cell cycle regulation, and apoptosis. However, little is known about the regulation of the REGγ-proteasome pathway. Here we demonstrate that REGγ can be SUMOylated in vitro and in vivo by SUMO-1, SUMO-2, and SUMO-3. The SUMO-E3 protein inhibitor of activated STAT (PIAS)1 physically associates with REGγ and promotes SUMOylation of REGγ. SUMOylation of REGγ was found to occur at multiple sites, including K6, K14, and K12. Mutation analysis indicated that these SUMO sites simultaneously contributed to the SUMOylation status of REGγ in cells. Posttranslational modification of REGγ by SUMO conjugation was revealed to mediate cytosolic translocation of REGγ and to cause increased stability of this proteasome activator. SUMOylation-deficient REGγ displayed attenuated ability to degrade p21(Waf//Cip1) due to reduced affinity of the REGγ SUMOylation-defective mutant for p21. Taken together, we report a previously unrecognized mechanism regulating the activity of the proteasome activator REGγ. This regulatory mechanism may enable REGγ to function as a more potent factor in protein degradation with a broader substrate spectrum.
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Affiliation(s)
- Yan Wu
- Institute of Biomedical Sciences, East China Normal University, 500 Dongchuan Road, Shanghai 200241, China
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30
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Ehrnhoefer DE, Sutton L, Hayden MR. Small changes, big impact: posttranslational modifications and function of huntingtin in Huntington disease. Neuroscientist 2011; 17:475-92. [PMID: 21311053 DOI: 10.1177/1073858410390378] [Citation(s) in RCA: 126] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Huntington disease (HD) is a neurodegenerative disorder caused by an elongated polyglutamine tract in huntingtin (htt). htt normally undergoes different posttranslational modifications (PTMs), including phosphorylation, SUMOylation, ubiquitination, acetylation, proteolytic cleavage, and palmitoylation. In the presence of the HD mutation, some PTMs are significantly altered and can result in changes in the clinical phenotype. A rate-limiting PTM is defined as one that can result in significant effects on the phenotype in animal models. For example, the prevention of proteolysis at D586 as well as constitutive phosphorylation at S13 and S16 can obviate the expression of phenotypic features of HD. The enzymes involved in these modifications such as caspase-6, the IκB kinase (IKK) complex, and still to be characterized phosphatases therefore represent promising therapeutic targets for HD. Identifying and testing specific modulators of PTMs now constitute the next big challenges in order to further validate these targets and proceed towards the goal of a mechanism-based treatment for HD.
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Affiliation(s)
- Dagmar E Ehrnhoefer
- Centre for Molecular Medicine and Therapeutics, Child & Family Research Institute, University of British Columbia, Vancouver, BC, Canada.
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31
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Gong F, Sun L, Wang Z, Shi J, Li W, Wang S, Han X, Sun Y. The BCL2 gene is regulated by a special AT-rich sequence binding protein 1-mediated long range chromosomal interaction between the promoter and the distal element located within the 3'-UTR. Nucleic Acids Res 2011; 39:4640-52. [PMID: 21310710 PMCID: PMC3113567 DOI: 10.1093/nar/gkr023] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The 279-bp major breakpoint region (mbr) within the 3′-untranslated region (3′-UTR) of the BCL2 gene is a binding site of special AT-rich sequence binding protein 1 (SATB1) that is well known to participate in the long-range regulation of gene transcription. Our previous studies have revealed that the mbr could regulate BCL2 transcription over a 200-kb distance and this regulatory function was closely related to SATB1. This study is to explore the underlying mechanism and its relevance to cellular apoptosis. With chromosome conformation capture (3C) and chromatin immunoprecipitation (ChIP) assays we demonstrated that the mbr could physically interact with BCL2 promoter through SATB1-mediated chromatin looping, which was required for epigenetic modifications of the promoter, CREB accessibility and high expression of the BCL2 gene. During early apoptosis, SATB1 was a key regulator of BCL2 expression. Inhibition of SATB1 cleavage by treatment of cells with a caspase-6 inhibitor or overexpression of mutant SATB1 that was resistant to caspase-6, inhibited disassembly of the SATB1-mediated chromatin loop and restored the BCL2 mRNA level in Jurkat cells. These data revealed a novel mechanism of BCL2 regulation and mechanistically link SATB1-mediated long-range interaction with the regulation of a gene controlling apoptosis pathway for the first time.
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Affiliation(s)
- Feiran Gong
- Key Laboratory of Human Functional Genomics of Jiangsu Province, Department of Cell Biology and Jiangsu Key Lab of Cancer Biomarkers, Prevention & Treatment, Cancer Center, Nanjing Medical University, Nanjing 210029, PR China
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32
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The SUMO pathway: emerging mechanisms that shape specificity, conjugation and recognition. Nat Rev Mol Cell Biol 2010; 11:861-71. [PMID: 21102611 DOI: 10.1038/nrm3011] [Citation(s) in RCA: 889] [Impact Index Per Article: 63.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Proteins of the small ubiquitin-related modifier (SUMO) family are conjugated to proteins to regulate such cellular processes as nuclear transport, transcription, chromosome segregation and DNA repair. Recently, numerous insights into regulatory mechanisms of the SUMO modification pathway have emerged. Although SUMO-conjugating enzymes can discriminate between SUMO targets, many substrates possess characteristics that facilitate their modification. Other post-translational modifications also regulate SUMO conjugation, suggesting that SUMO signalling is integrated with other signal transduction pathways. A better understanding of SUMO regulatory mechanisms will lead to improved approaches for analysing the function of SUMO and substrate conjugation in distinct cellular pathways.
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