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Romero H, Schmidt A, Cardoso CM. Protein Level Quantification Across Fluorescence-based Platforms. Bio Protoc 2023; 13:e4834. [PMID: 37817905 PMCID: PMC10560694 DOI: 10.21769/bioprotoc.4834] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 08/02/2023] [Accepted: 08/02/2023] [Indexed: 10/12/2023] Open
Abstract
Biological processes are dependent on protein concentration and there is an inherent variability among cells even in environment-controlled conditions. Determining the amount of protein of interest in a cell is relevant to quantitatively relate it with the cells (patho)physiology. Previous studies used either western blot to determine the average amount of protein per cell in a population or fluorescence intensity to provide a relative amount of protein. This method combines both techniques. First, the protein of interest is purified, and its concentration determined. Next, cells containing the protein of interest with a fluorescent tag are sorted into different levels of intensity using fluorescence-activated cell sorting, and the amount of protein for each intensity category is calculated using the purified protein as calibration. Lastly, a calibration curve allows the direct relation of the amount of protein to the intensity levels determined with any instrument able to measure intensity levels. Once a fluorescence-based instrument is calibrated, it is possible to determine protein concentrations based on intensity. Key features • This method allows the evaluation and comparison of protein concentration in cells based on fluorescence intensity. • Requires protein purification and fluorescence-activated cell sorting. • Once calibrated for one protein, it allows determination of the levels of this protein using any fluorescence-based instrument. • Allows to determine subcellular local protein concentration based on combining volumetric and intensity measurements.
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Affiliation(s)
- Hector Romero
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Annika Schmidt
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Cristina M. Cardoso
- Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
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2
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Schmidt A, Frei J, Poetsch A, Chittka A, Zhang H, Aßmann C, Lehmkuhl A, Bauer UM, Nuber UA, Cardoso MC. MeCP2 heterochromatin organization is modulated by arginine methylation and serine phosphorylation. Front Cell Dev Biol 2022; 10:941493. [PMID: 36172281 PMCID: PMC9510713 DOI: 10.3389/fcell.2022.941493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Accepted: 08/19/2022] [Indexed: 11/23/2022] Open
Abstract
Rett syndrome is a human intellectual disability disorder that is associated with mutations in the X-linked MECP2 gene. The epigenetic reader MeCP2 binds to methylated cytosines on the DNA and regulates chromatin organization. We have shown previously that MECP2 Rett syndrome missense mutations are impaired in chromatin binding and heterochromatin reorganization. Here, we performed a proteomics analysis of post-translational modifications of MeCP2 isolated from adult mouse brain. We show that MeCP2 carries various post-translational modifications, among them phosphorylation on S80 and S421, which lead to minor changes in either heterochromatin binding kinetics or clustering. We found that MeCP2 is (di)methylated on several arginines and that this modification alters heterochromatin organization. Interestingly, we identified the Rett syndrome mutation site R106 as a dimethylation site. In addition, co-expression of protein arginine methyltransferases (PRMT)1 and PRMT6 lead to a decrease of heterochromatin clustering. Altogether, we identified and validated novel modifications of MeCP2 in the brain and show that these can modulate its ability to bind as well as reorganize heterochromatin, which may play a role in the pathology of Rett syndrome.
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Affiliation(s)
- Annika Schmidt
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Jana Frei
- Stem Cell and Developmental Biology, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Ansgar Poetsch
- Queen Mary School, Medical College, Nanchang University, Nanchang, China
- Plant Biochemistry, Ruhr University Bochum, Bochum, Germany
- College of Marine Life Sciences, Ocean University of China, Qingdao, China
| | - Alexandra Chittka
- Division of Medicine, The Wolfson Institute for Biomedical Research, University College London, London, United Kingdom
- Department of Neuromuscular Diseases, Queen Square Institute of Neurology, University College London, London, United Kingdom
| | - Hui Zhang
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Chris Aßmann
- Institute of Molecular Biology and Tumor Research, Philipps University Marburg, Marburg, Germany
| | - Anne Lehmkuhl
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
| | - Uta-Maria Bauer
- Institute of Molecular Biology and Tumor Research, Philipps University Marburg, Marburg, Germany
| | - Ulrike A. Nuber
- Stem Cell and Developmental Biology, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
- *Correspondence: Ulrike A. Nuber, ; M. Cristina Cardoso,
| | - M. Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technical University of Darmstadt, Darmstadt, Germany
- *Correspondence: Ulrike A. Nuber, ; M. Cristina Cardoso,
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3
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Chakrabarti A, Narayana C, Joshi N, Garg S, Garg LC, Ranganathan A, Sagar R, Pati S, Singh S. Metalloprotease Gp63-Targeting Novel Glycoside Exhibits Potential Antileishmanial Activity. Front Cell Infect Microbiol 2022; 12:803048. [PMID: 35601095 PMCID: PMC9115111 DOI: 10.3389/fcimb.2022.803048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 03/14/2022] [Indexed: 11/17/2022] Open
Abstract
Visceral leishmaniasis (VL) and post kala-azar dermal leishmaniasis (PKDL) affect most of the poor populations worldwide. The current treatment modalities include liposomal formulation or deoxycholate salt of amphotericin B, which has been associated with various complications and severe side effects. Encouraged from the recent marked antimalarial effects from plant-derived glycosides, in this study, we have exploited a green chemistry-based approach to chemically synthesize a library of diverse glycoside derivatives (Gly1–12) and evaluated their inhibitory efficacy against the AG83 strain of Leishmania donovani. Among the synthesized glycosides, the in vitro inhibitory activity of Glycoside-2 (Gly2) (1.13 µM IC50 value) on L. donovani promastigote demonstrated maximum cytotoxicity with ~94% promastigote death as compared to amphotericin B that was taken as a positive control. The antiproliferative effect of Gly2 on promastigote encouraged us to analyze the structure–activity relationship of Gly2 with Gp63, a zinc metalloprotease that majorly localizes at the surface of the promastigote and has a role in its development and multiplication. The result demonstrated the exceptional binding affinity of Gly2 toward the catalytic domain of Gp63. These data were thereafter validated through cellular thermal shift assay in a physiologically relevant cellular environment. Mechanistically, reduced multiplication of promastigotes on treatment with Gly2 induces the destabilization of redox homeostasis in promastigotes by enhancing reactive oxygen species (ROS), coupled with depolarization of the mitochondrial membrane. Additionally, Gly2 displayed strong lethal effects on infectivity and multiplication of amastigote inside the macrophage in the amastigote–macrophage infection model in vitro as compared to amphotericin B treatment. Gp63 is also known to bestow protection against complement-mediated lysis of parasites. Interestingly, Gly2 treatment enhances the complement-mediated lysis of L. donovani promastigotes in serum physiological conditions. In addition, Gly2 was found to be equally effective against the clinical promastigote forms of PKDL strain (IC50 value of 1.97 µM); hence, it could target both VL and PKDL simultaneously. Taken together, this study reports the serendipitous discovery of Gly2 with potent antileishmanial activity and proves to be a novel chemotherapeutic prototype against VL and PKDL.
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Affiliation(s)
- Amrita Chakrabarti
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
| | - Chintam Narayana
- Department of Chemistry, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
| | - Nishant Joshi
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
| | - Swati Garg
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
- Special Centre for Molecular Medicine, Jawaharlal Nehru University (JNU), New Delhi, India
| | - Lalit C. Garg
- Gene Regulation Laboratory, National Institute of Immunology, New Delhi, India
| | - Anand Ranganathan
- Special Centre for Molecular Medicine, Jawaharlal Nehru University (JNU), New Delhi, India
| | - Ram Sagar
- Department of Chemistry, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
- Department of Chemistry, Institute of Science, Banaras Hindu University, Varanasi, India
- *Correspondence: Shailja Singh, ; Soumya Pati, ; Ram Sagar,
| | - Soumya Pati
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
- *Correspondence: Shailja Singh, ; Soumya Pati, ; Ram Sagar,
| | - Shailja Singh
- Department of Life Sciences, School of Natural Sciences, Shiv Nadar University, Greater Noida, India
- Special Centre for Molecular Medicine, Jawaharlal Nehru University (JNU), New Delhi, India
- *Correspondence: Shailja Singh, ; Soumya Pati, ; Ram Sagar,
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4
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Jabre S, Hleihel W, Coirault C. Nuclear Mechanotransduction in Skeletal Muscle. Cells 2021; 10:cells10020318. [PMID: 33557157 PMCID: PMC7913907 DOI: 10.3390/cells10020318] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/11/2022] Open
Abstract
Skeletal muscle is composed of multinucleated, mature muscle cells (myofibers) responsible for contraction, and a resident pool of mononucleated muscle cell precursors (MCPs), that are maintained in a quiescent state in homeostatic conditions. Skeletal muscle is remarkable in its ability to adapt to mechanical constraints, a property referred as muscle plasticity and mediated by both MCPs and myofibers. An emerging body of literature supports the notion that muscle plasticity is critically dependent upon nuclear mechanotransduction, which is transduction of exterior physical forces into the nucleus to generate a biological response. Mechanical loading induces nuclear deformation, changes in the nuclear lamina organization, chromatin condensation state, and cell signaling, which ultimately impacts myogenic cell fate decisions. This review summarizes contemporary insights into the mechanisms underlying nuclear force transmission in MCPs and myofibers. We discuss how the cytoskeleton and nuclear reorganizations during myogenic differentiation may affect force transmission and nuclear mechanotransduction. We also discuss how to apply these findings in the context of muscular disorders. Finally, we highlight current gaps in knowledge and opportunities for further research in the field.
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Affiliation(s)
- Saline Jabre
- Sorbonne Université, INSERM UMRS-974 and Institut de Myologie, 75013 Paris, France;
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kasik (USEK), Jounieh 446, Lebanon;
| | - Walid Hleihel
- Department of Biology, Faculty of Arts and Sciences, Holy Spirit University of Kasik (USEK), Jounieh 446, Lebanon;
- Department of Basic Health Sciences, Faculty of Medicine, Holy Spirit University of Kaslik (USEK), Jounieh 446, Lebanon
| | - Catherine Coirault
- Sorbonne Université, INSERM UMRS-974 and Institut de Myologie, 75013 Paris, France;
- Correspondence:
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5
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Nannini F, Parekh F, Wawrzyniecka P, Mekkaoui L, Righi M, Dastjerdi FV, Yeung J, Roddie C, Bai Y, Ma B, Ferrari M, Onuoha S, Chester K, Pule M. A primer set for the rapid isolation of scFv fragments against cell surface antigens from immunised rats. Sci Rep 2020; 10:19168. [PMID: 33154441 PMCID: PMC7644676 DOI: 10.1038/s41598-020-76069-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/21/2020] [Indexed: 12/20/2022] Open
Abstract
Antibody phage display is a powerful platform for discovery of clinically applicable high affinity monoclonal antibodies against a broad range of targets. Libraries generated from immunized animals offer the advantage of in vivo affinity-maturation of V regions prior to library generation. Despite advantages, few studies have described isolation of antibodies from rats using immune phage display. In our study, we describe a novel primer set, covering the full rat heavy chain variable and kappa light chain variable regions repertoire for the generation of an unbiased immune libraries. Since the immune repertoire of rats is poorly understood, we first performed a deep sequencing analysis of the V(D)J regions of VH and VLK genes, demonstrating the high abundance of IGVH2 and IGVH5 families for VH and IGVLK12 and IGVLK22 for VLK. The comparison of gene's family usage in naïve rats have been used to validate the frequency's distribution of the primer set, confirming the absence of PCR-based biases. The primers were used to generate and assemble a phage display library from human CD160-vaccinated rats. CD160 represents a valid therapeutic target as it has been shown to be expressed on chronic lymphocytic leukaemia cells and on the surface of newly formed vessels. We utilised a novel phage display panning strategy to isolate a high affinity pool (KD range: 0.399-233 nM) of CD160 targeting monoclonal antibodies. Subsequently, identified binders were tested for function as third generation Chimeric Antigen Receptors (CAR) T cells demonstrating specific cytolytic activity. Our novel primer set coupled with a streamlined strategy for phage display panning enable the rapid isolation and identification of high affinity antibodies from immunised rats. The therapeutic utility of these antibodies was demonstrated in CAR format.
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Affiliation(s)
- Francesco Nannini
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | - Farhaan Parekh
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | - Patrycja Wawrzyniecka
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | - Leila Mekkaoui
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | - Matteo Righi
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | | | - Jenny Yeung
- Research Department of Oncology, UCL Cancer Institute, London, UK
| | - Claire Roddie
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK
| | | | - Biao Ma
- Autolus Therapeutics, London, UK
| | | | | | - Kerry Chester
- Research Department of Oncology, UCL Cancer Institute, London, UK
| | - Martin Pule
- Research Department of Haematology, UCL Cancer Institute, 72 Huntley Street, London, WC1E 6DD, UK.
- Autolus Therapeutics, London, UK.
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6
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Ludwig AK, Zhang P, Hastert FD, Meyer S, Rausch C, Herce HD, Müller U, Lehmkuhl A, Hellmann I, Trummer C, Storm C, Leonhardt H, Cardoso MC. Binding of MBD proteins to DNA blocks Tet1 function thereby modulating transcriptional noise. Nucleic Acids Res 2017; 45:2438-2457. [PMID: 27923996 PMCID: PMC5389475 DOI: 10.1093/nar/gkw1197] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2016] [Accepted: 11/20/2016] [Indexed: 12/18/2022] Open
Abstract
Aberrant DNA methylation is a hallmark of various human disorders, indicating that the spatial and temporal regulation of methylation readers and modifiers is imperative for development and differentiation. In particular, the cross-regulation between 5-methylcytosine binders (MBD) and modifiers (Tet) has not been investigated. Here, we show that binding of Mecp2 and Mbd2 to DNA protects 5-methylcytosine from Tet1-mediated oxidation. The mechanism is not based on competition for 5-methylcytosine binding but on Mecp2 and Mbd2 directly restricting Tet1 access to DNA. We demonstrate that the efficiency of this process depends on the number of bound MBDs per DNA molecule. Accordingly, we find 5-hydroxymethylcytosine enriched at heterochromatin of Mecp2-deficient neurons of a mouse model for Rett syndrome and Tet1-induced reexpression of silenced major satellite repeats. These data unveil fundamental regulatory mechanisms of Tet enzymes and their potential pathophysiological role in Rett syndrome. Importantly, it suggests that Mecp2 and Mbd2 have an essential physiological role as guardians of the epigenome.
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Affiliation(s)
- Anne K Ludwig
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Peng Zhang
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Florian D Hastert
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Stephanie Meyer
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Cathia Rausch
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Henry D Herce
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Udo Müller
- Human Biology and BioImaging, Department of Biology II, LMU Munich, 82152 Martinsried, Germany
| | - Anne Lehmkuhl
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Ines Hellmann
- Anthropology and Human Genomics, Department Biology II, LMU Munich, 82152 Martinsried, Germany
| | - Carina Trummer
- Human Biology and BioImaging, Department of Biology II, LMU Munich, 82152 Martinsried, Germany
| | - Christian Storm
- Chemical Plant Ecology, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Heinrich Leonhardt
- Human Biology and BioImaging, Department of Biology II, LMU Munich, 82152 Martinsried, Germany
| | - M Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
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7
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Zhang P, Rausch C, Hastert FD, Boneva B, Filatova A, Patil SJ, Nuber UA, Gao Y, Zhao X, Cardoso MC. Methyl-CpG binding domain protein 1 regulates localization and activity of Tet1 in a CXXC3 domain-dependent manner. Nucleic Acids Res 2017; 45:7118-7136. [PMID: 28449087 PMCID: PMC5499542 DOI: 10.1093/nar/gkx281] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 03/30/2017] [Accepted: 04/06/2017] [Indexed: 12/20/2022] Open
Abstract
Cytosine modifications diversify and structure the genome thereby controlling proper development and differentiation. Here, we focus on the interplay of the 5-methylcytosine reader Mbd1 and modifier Tet1 by analyzing their dynamic subcellular localization and the formation of the Tet oxidation product 5-hydroxymethylcytosine in mammalian cells. Our results demonstrate that Mbd1 enhances Tet1-mediated 5-methylcytosine oxidation. We show that this is due to enhancing the localization of Tet1, but not of Tet2 and Tet3 at heterochromatic DNA. We find that the recruitment of Tet1 and concomitantly its catalytic activity eventually leads to the displacement of Mbd1 from methylated DNA. Finally, we demonstrate that increased Tet1 heterochromatin localization and 5-methylcytosine oxidation are dependent on the CXXC3 domain of Mbd1, which recognizes unmethylated CpG dinucleotides. The Mbd1 CXXC3 domain deletion isoform, which retains only binding to methylated CpGs, on the other hand, blocks Tet1-mediated 5-methylcytosine to 5-hydroxymethylcytosine conversion, indicating opposite biological effects of Mbd1 isoforms. Our study provides new insights on how cytosine modifications, their modifiers and readers cross-regulate themselves.
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Affiliation(s)
- Peng Zhang
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Cathia Rausch
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Florian D. Hastert
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Boyana Boneva
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Alina Filatova
- Stem Cell and Developmental Biology, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Sujit J. Patil
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Ulrike A. Nuber
- Stem Cell and Developmental Biology, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
| | - Yu Gao
- Waisman Center & Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - Xinyu Zhao
- Waisman Center & Department of Neuroscience, University of Wisconsin-Madison, Madison, WI 53705, USA
| | - M. Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstrasse 10, 64287 Darmstadt, Germany
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8
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Zhang P, Ludwig AK, Hastert FD, Rausch C, Lehmkuhl A, Hellmann I, Smets M, Leonhardt H, Cardoso MC. L1 retrotransposition is activated by Ten-eleven-translocation protein 1 and repressed by methyl-CpG binding proteins. Nucleus 2017; 8:548-562. [PMID: 28524723 PMCID: PMC5703239 DOI: 10.1080/19491034.2017.1330238] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
One of the major functions of DNA methylation is the repression of transposable elements, such as the long-interspersed nuclear element 1 (L1). The underlying mechanism(s), however, are unclear. Here, we addressed how retrotransposon activation and mobilization are regulated by methyl-cytosine modifying ten-eleven-translocation (Tet) proteins and how this is modulated by methyl-CpG binding domain (MBD) proteins. We show that Tet1 activates both, endogenous and engineered L1 retrotransposons. Furthermore, we found that Mecp2 and Mbd2 repress Tet1-mediated activation of L1 by preventing 5hmC formation at the L1 promoter. Finally, we demonstrate that the methyl-CpG binding domain, as well as the adjacent non-sequence specific DNA binding domain of Mecp2 are each sufficient to mediate repression of Tet1-induced L1 mobilization. Our study reveals a mechanism how L1 elements get activated in the absence of Mecp2 and suggests that Tet1 may contribute to Mecp2/Mbd2-deficiency phenotypes, such as the Rett syndrome. We propose that the balance between methylation "reader" and "eraser/writer" controls L1 retrotransposition.
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Affiliation(s)
- Peng Zhang
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
| | - Anne K Ludwig
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
| | - Florian D Hastert
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
| | - Cathia Rausch
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
| | - Anne Lehmkuhl
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
| | - Ines Hellmann
- b Anthropology and Human Genomics, Department Biology II , LMU Munich , Germany
| | - Martha Smets
- c Human Biology and BioImaging, Department of Biology II , LMU Munich , Germany
| | - Heinrich Leonhardt
- c Human Biology and BioImaging, Department of Biology II , LMU Munich , Germany
| | - M Cristina Cardoso
- a Department of Biology , Technical University Darmstadt , Darmstadt , Germany
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9
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Becker A, Zhang P, Allmann L, Meilinger D, Bertulat B, Eck D, Hofstaetter M, Bartolomei G, Hottiger MO, Schreiber V, Leonhardt H, Cardoso MC. Poly(ADP-ribosyl)ation of Methyl CpG Binding Domain Protein 2 Regulates Chromatin Structure. J Biol Chem 2016; 291:4873-81. [PMID: 26772194 PMCID: PMC4777825 DOI: 10.1074/jbc.m115.698357] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Indexed: 11/06/2022] Open
Abstract
The epigenetic information encoded in the genomic DNA methylation pattern is translated by methylcytosine binding proteins like MeCP2 into chromatin topology and structure and gene activity states. We have shown previously that the MeCP2 level increases during differentiation and that it causes large-scale chromatin reorganization, which is disturbed by MeCP2 Rett syndrome mutations. Phosphorylation and other posttranslational modifications of MeCP2 have been described recently to modulate its function. Here we show poly(ADP-ribosyl)ation of endogenous MeCP2 in mouse brain tissue. Consequently, we found that MeCP2 induced aggregation of pericentric heterochromatin and that its chromatin accumulation was enhanced in poly(ADP-ribose) polymerase (PARP) 1(-/-) compared with wild-type cells. We mapped the poly(ADP-ribosyl)ation domains and engineered MeCP2 mutation constructs to further analyze potential effects on DNA binding affinity and large-scale chromatin remodeling. Single or double deletion of the poly(ADP-ribosyl)ated regions and PARP inhibition increased the heterochromatin clustering ability of MeCP2. Increased chromatin clustering may reflect increased binding affinity. In agreement with this hypothesis, we found that PARP-1 deficiency significantly increased the chromatin binding affinity of MeCP2 in vivo. These data provide novel mechanistic insights into the regulation of MeCP2-mediated, higher-order chromatin architecture and suggest therapeutic opportunities to manipulate MeCP2 function.
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Affiliation(s)
- Annette Becker
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Peng Zhang
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Lena Allmann
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Daniela Meilinger
- the Center for Integrated Protein Science at the Department of Biology, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - Bianca Bertulat
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Daniel Eck
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Maria Hofstaetter
- the Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Giody Bartolomei
- the Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland, and
| | - Michael O Hottiger
- the Department of Molecular Mechanisms of Disease, University of Zurich, 8057 Zurich, Switzerland, and
| | - Valérie Schreiber
- UMR7242 Biotechnology and Cell Signaling, Laboratory of Excellence Medalis, Strasbourg University, CNRS, Ecole Superieure de Biotechnologie de Strasbourg, BP10413, 67412 Illkirch Cedex, France
| | - Heinrich Leonhardt
- the Center for Integrated Protein Science at the Department of Biology, Ludwig Maximilians University Munich, 82152 Planegg-Martinsried, Germany
| | - M Cristina Cardoso
- From the Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany,
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10
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Jost KL, Bertulat B, Rapp A, Brero A, Hardt T, Domaing P, Gösele C, Schulz H, Hübner N, Cardoso MC. Gene repositioning within the cell nucleus is not random and is determined by its genomic neighborhood. Epigenetics Chromatin 2015; 8:36. [PMID: 26388944 PMCID: PMC4574441 DOI: 10.1186/s13072-015-0025-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 09/01/2015] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Heterochromatin has been reported to be a major silencing compartment during development and differentiation. Prominent heterochromatin compartments are located at the nuclear periphery and inside the nucleus (e.g., pericentric heterochromatin). Whether the position of a gene in relation to some or all heterochromatin compartments matters remains a matter of debate, which we have addressed in this study. Answering this question demanded solving the technical challenges of 3D measurements and the large-scale morphological changes accompanying cellular differentiation. RESULTS Here, we investigated the proximity effects of the nuclear periphery and pericentric heterochromatin on gene expression and additionally considered the effect of neighboring genomic features on a gene's nuclear position. Using a well-established myogenic in vitro differentiation system and a differentiation-independent heterochromatin remodeling system dependent on ectopic MeCP2 expression, we first identified genes with statistically significant expression changes by transcriptional profiling. We identified nuclear gene positions by 3D fluorescence in situ hybridization followed by 3D distance measurements toward constitutive and facultative heterochromatin domains. Single-cell-based normalization enabled us to acquire morphologically unbiased data and we finally correlated changes in gene positioning to changes in transcriptional profiles. We found no significant correlation of gene silencing and proximity to constitutive heterochromatin and a rather unexpected inverse correlation of gene activity and position relative to facultative heterochromatin at the nuclear periphery. CONCLUSION In summary, our data question the hypothesis of heterochromatin as a general silencing compartment. Nonetheless, compared to a simulated random distribution, we found that genes are not randomly located within the nucleus. An analysis of neighboring genomic context revealed that gene location within the nucleus is rather dependent on CpG islands, GC content, gene density, and short and long interspersed nuclear elements, collectively known as RIDGE (regions of increased gene expression) properties. Although genes do not move away/to the heterochromatin upon up-/down-regulation, genomic regions with RIDGE properties are generally excluded from peripheral heterochromatin. Hence, we suggest that individual gene activity does not influence gene positioning, but rather chromosomal context matters for sub-nuclear location.
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Affiliation(s)
- K Laurence Jost
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Bianca Bertulat
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Alexander Rapp
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
| | - Alessandro Brero
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Tanja Hardt
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Petra Domaing
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Claudia Gösele
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Herbert Schulz
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - Norbert Hübner
- Max Delbrück Center for Molecular Medicine, 13125 Berlin, Germany
| | - M Cristina Cardoso
- Department of Biology, Technische Universität Darmstadt, 64287 Darmstadt, Germany
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11
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Bauer C, Göbel K, Nagaraj N, Colantuoni C, Wang M, Müller U, Kremmer E, Rottach A, Leonhardt H. Phosphorylation of TET proteins is regulated via O-GlcNAcylation by the O-linked N-acetylglucosamine transferase (OGT). J Biol Chem 2015; 290:4801-4812. [PMID: 25568311 PMCID: PMC4335217 DOI: 10.1074/jbc.m114.605881] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
TET proteins oxidize 5-methylcytosine to 5-hydroxymethylcytosine, 5-formylcytosine, and 5-carboxylcytosine and thus provide a possible means for active DNA demethylation in mammals. Although their catalytic mechanism is well characterized and the catalytic dioxygenase domain is highly conserved, the function of the regulatory regions (the N terminus and the low-complexity insert between the two parts of the dioxygenase domains) is only poorly understood. Here, we demonstrate that TET proteins are subject to a variety of post-translational modifications that mostly occur at these regulatory regions. We mapped TET modification sites at amino acid resolution and show for the first time that TET1, TET2, and TET3 are highly phosphorylated. The O-linked GlcNAc transferase, which we identified as a strong interactor with all three TET proteins, catalyzes the addition of a GlcNAc group to serine and threonine residues of TET proteins and thereby decreases both the number of phosphorylation sites and site occupancy. Interestingly, the different TET proteins display unique post-translational modification patterns, and some modifications occur in distinct combinations. In summary, our results provide a novel potential mechanism for TET protein regulation based on a dynamic interplay of phosphorylation and O-GlcNAcylation at the N terminus and the low-complexity insert region. Our data suggest strong cross-talk between the modification sites that could allow rapid adaption of TET protein localization, activity, or targeting due to changing environmental conditions as well as in response to external stimuli.
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Affiliation(s)
- Christina Bauer
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried
| | - Klaus Göbel
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried
| | | | | | - Mengxi Wang
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried
| | - Udo Müller
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried
| | - Elisabeth Kremmer
- Institute for Molecular Immunology, Helmholtz Center Munich, 81377 München-Groβhadern
| | - Andrea Rottach
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried,.
| | - Heinrich Leonhardt
- Biocenter, Ludwig-Maximilians University Munich, 82152 Planegg-Martinsried,; Center for Integrated Protein Science Munich (CIPSM), 81377 München, Germany.
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12
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Romero-Fernández I, Casas-Delucchi CS, Cano-Linares M, Arroyo M, Sánchez A, Cardoso MC, Marchal JA. Epigenetic modifications in sex heterochromatin of vole rodents. Chromosoma 2014; 124:341-51. [PMID: 25527445 DOI: 10.1007/s00412-014-0502-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Revised: 12/05/2014] [Accepted: 12/05/2014] [Indexed: 11/26/2022]
Abstract
The genome of some vole rodents contains large blocks of heterochromatin coupled to the sex chromosomes. While the DNA content of these heterochromatic blocks has been extensively analyzed, little is known about the epigenetic modifications controlling their structure and dynamics. To better understand its organization and functions within the nucleus, we have compared the distribution pattern of several epigenetic marks in cells from two species, Microtus agrestis and Microtus cabrerae. We first could show that the heterochromatic blocks are identifiable within the nuclei due to their AT enrichment detectable by DAPI staining. By immunostaining analyses, we demonstrated that enrichment in H3K9me3 and HP1, depletion of DNA methylation as well as H4K8ac and H3K4me2, are major conserved epigenetic features of this heterochromatin in both sex chromosomes. Furthermore, we provide evidence of transcriptional activity for some repeated DNAs in cultivated cells. These transcripts are partially polyadenylated and their levels are not altered during mitotic arrest. In summary, we show here that enrichment in H3K9me3 and HP1, DNA demethylation, and transcriptional activity are major epigenetic features of sex heterochromatin in vole rodents.
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Affiliation(s)
- I Romero-Fernández
- Department of Experimental Biology, University of Jaén, Jaén, E-23071, Spain
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13
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Song C, Feodorova Y, Guy J, Peichl L, Jost KL, Kimura H, Cardoso MC, Bird A, Leonhardt H, Joffe B, Solovei I. DNA methylation reader MECP2: cell type- and differentiation stage-specific protein distribution. Epigenetics Chromatin 2014; 7:17. [PMID: 25170345 PMCID: PMC4148084 DOI: 10.1186/1756-8935-7-17] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2014] [Accepted: 07/23/2014] [Indexed: 11/21/2022] Open
Abstract
Background Methyl-CpG binding protein 2 (MECP2) is a protein that specifically binds methylated DNA, thus regulating transcription and chromatin organization. Mutations in the gene have been identified as the principal cause of Rett syndrome, a severe neurological disorder. Although the role of MECP2 has been extensively studied in nervous tissues, still very little is known about its function and cell type specific distribution in other tissues. Results Using immunostaining on tissue cryosections, we characterized the distribution of MECP2 in 60 cell types of 16 mouse neuronal and non-neuronal tissues. We show that MECP2 is expressed at a very high level in all retinal neurons except rod photoreceptors. The onset of its expression during retina development coincides with massive synapse formation. In contrast to astroglia, retinal microglial cells lack MECP2, similar to microglia in the brain, cerebellum, and spinal cord. MECP2 is also present in almost all non-neural cell types, with the exception of intestinal epithelial cells, erythropoietic cells, and hair matrix keratinocytes. Our study demonstrates the role of MECP2 as a marker of the differentiated state in all studied cells other than oocytes and spermatogenic cells. MECP2-deficient male (Mecp2-/y) mice show no apparent defects in the morphology and development of the retina. The nuclear architecture of retinal neurons is also unaffected as the degree of chromocenter fusion and the distribution of major histone modifications do not differ between Mecp2-/y and Mecp2wt mice. Surprisingly, the absence of MECP2 is not compensated by other methyl-CpG binding proteins. On the contrary, their mRNA levels were downregulated in Mecp2-/y mice. Conclusions MECP2 is almost universally expressed in all studied cell types with few exceptions, including microglia. MECP2 deficiency does not change the nuclear architecture and epigenetic landscape of retinal cells despite the missing compensatory expression of other methyl-CpG binding proteins. Furthermore, retinal development and morphology are also preserved in Mecp2-null mice. Our study reveals the significance of MECP2 function in cell differentiation and sets the basis for future investigations in this direction.
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Affiliation(s)
- Congdi Song
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
| | - Yana Feodorova
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
| | - Jacky Guy
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3JR Edinburgh, UK
| | - Leo Peichl
- Max Planck Institute for Brain Research, Max-von-Laue-Str. 4, Frankfurt am Main 60438, Germany
| | - Katharina Laurence Jost
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstr. 10, Darmstadt 64287, Germany
| | - Hiroshi Kimura
- Graduate School of Frontier Biosciences, Osaka University, 1-3 Yamadaoka, 565-0871 Suita, Osaka, Japan
| | - Maria Cristina Cardoso
- Cell Biology and Epigenetics, Department of Biology, Technische Universität Darmstadt, Schnittspahnstr. 10, Darmstadt 64287, Germany
| | - Adrian Bird
- Wellcome Trust Centre for Cell Biology, University of Edinburgh, EH9 3JR Edinburgh, UK
| | - Heinrich Leonhardt
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
| | - Boris Joffe
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
| | - Irina Solovei
- Department of Biology II, Center for Integrated Protein Science Munich (CIPSM), Ludwig Maximilians University Munich, Grosshadernerstrasse 2, 82152 Planegg-Martinsried, Germany
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14
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A role for MeCP2 in switching gene activity via chromatin unfolding and HP1γ displacement. PLoS One 2013; 8:e69347. [PMID: 23935992 PMCID: PMC3720725 DOI: 10.1371/journal.pone.0069347] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Accepted: 06/07/2013] [Indexed: 11/19/2022] Open
Abstract
Methyl-CpG-binding protein 2 (MeCP2) is generally considered to act as a transcriptional repressor, whereas recent studies suggest that MeCP2 is also involved in transcription activation. To gain insight into this dual function of MeCP2, we assessed the impact of MeCP2 on higher-order chromatin structure in living cells using mammalian cell systems harbouring a lactose operator and reporter gene-containing chromosomal domain to assess the effect of lactose repressor-tagged MeCP2 (and separate MeCP2 domains) binding in living cells. Our data reveal that targeted binding of MeCP2 elicits extensive chromatin unfolding. MeCP2-induced chromatin unfolding is triggered independently of the methyl-cytosine-binding domain. Interestingly, MeCP2 binding triggers the loss of HP1γ at the chromosomal domain and an increased HP1γ mobility, which is not observed for HP1α and HP1β. Surprisingly, MeCP2-induced chromatin unfolding is not associated with transcriptional activation. Our study suggests a novel role for MeCP2 in reorganizing chromatin to facilitate a switch in gene activity.
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15
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Becker A, Allmann L, Hofstätter M, Casà V, Weber P, Lehmkuhl A, Herce HD, Cardoso MC. Direct homo- and hetero-interactions of MeCP2 and MBD2. PLoS One 2013; 8:e53730. [PMID: 23335972 PMCID: PMC3546041 DOI: 10.1371/journal.pone.0053730] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 12/04/2012] [Indexed: 01/11/2023] Open
Abstract
Epigenetic marks like methylation of cytosines at CpG dinucleotides are essential for mammalian development and play a major role in the regulation of gene expression and chromatin architecture. The methyl-cytosine binding domain (MBD) protein family recognizes and translates this methylation mark. We have recently shown that the level of MeCP2 and MBD2, two members of the MBD family, increased during differentiation and their ectopic expression induced heterochromatin clustering in vivo. As oligomerization of these MBD proteins could constitute a factor contributing to the chromatin clustering effect, we addressed potential associations among the MBD family performing a series of different interaction assays in vitro as well as in vivo. Using recombinant purified MBDs we found that MeCP2 and MBD2 showed the stronger self and cross association as compared to the other family members. Besides demonstrating that these homo- and hetero-interactions occur in the absence of DNA, we could confirm them in mammalian cells using co-immunoprecipitation analysis. Employing a modified form of the fluorescent two-hybrid protein-protein interaction assay, we could clearly visualize these associations in single cells in vivo. Deletion analysis indicated that the region of MeCP2 comprising amino acids 163–309 as well the first 152 amino acids of MBD2 are the domains responsible for MeCP2 and MBD2 associations. Our results strengthen the possibility that MeCP2 and MBD2 direct interactions could crosslink chromatin fibers and therefore give novel insight into the molecular mechanism of MBD mediated global heterochromatin architecture.
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Affiliation(s)
- Annette Becker
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Lena Allmann
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | | | - Valentina Casà
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Patrick Weber
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Anne Lehmkuhl
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - Henry D. Herce
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
| | - M. Cristina Cardoso
- Department of Biology, Technische Universität Darmstadt, Darmstadt, Germany
- * E-mail:
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16
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MeCP2 dependent heterochromatin reorganization during neural differentiation of a novel Mecp2-deficient embryonic stem cell reporter line. PLoS One 2012; 7:e47848. [PMID: 23112857 PMCID: PMC3480415 DOI: 10.1371/journal.pone.0047848] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Accepted: 09/21/2012] [Indexed: 01/17/2023] Open
Abstract
The X-linked Mecp2 is a known interpreter of epigenetic information and mutated in Rett syndrome, a complex neurological disease. MeCP2 recruits HDAC complexes to chromatin thereby modulating gene expression and, importantly regulates higher order heterochromatin structure. To address the effects of MeCP2 deficiency on heterochromatin organization during neural differentiation, we developed a versatile model for stem cell in vitro differentiation. Therefore, we modified murine Mecp2 deficient (Mecp2−/y) embryonic stem cells to generate cells exhibiting green fluorescent protein expression upon neural differentiation. Subsequently, we quantitatively analyzed heterochromatin organization during neural differentiation in wild type and in Mecp2 deficient cells. We found that MeCP2 protein levels increase significantly during neural differentiation and accumulate at constitutive heterochromatin. Statistical analysis of Mecp2 wild type neurons revealed a significant clustering of heterochromatin per nuclei with progressing differentiation. In contrast we found Mecp2 deficient neurons and astroglia cells to be significantly impaired in heterochromatin reorganization. Our results (i) introduce a new and manageable cellular model to study the molecular effects of Mecp2 deficiency, and (ii) support the view of MeCP2 as a central protein in heterochromatin architecture in maturating cells, possibly involved in stabilizing their differentiated state.
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Ricceri L, De Filippis B, Laviola G. Rett syndrome treatment in mouse models: searching for effective targets and strategies. Neuropharmacology 2012; 68:106-15. [PMID: 22940001 DOI: 10.1016/j.neuropharm.2012.08.010] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 08/08/2012] [Accepted: 08/13/2012] [Indexed: 11/24/2022]
Abstract
Rett syndrome (RTT) is a pervasive developmental disorder, primarily affecting girls with a prevalence of 1 in every 10,000 births; it represents the second most common cause of intellectual disability in females. Mutations in the gene encoding methyl-CpG-binding protein 2 (MECP2) have been identified as clear etiological factors in more than 90% of classical RTT cases. Whereas the mechanisms leading to the severe, progressive and specific neurological dysfunctions when this gene is mutated still remain to be elucidated, a series of different mouse models have been generated, bearing different Mecp2 mutation. Neurobehavioural analysis in these mouse lines have been carried out and phenotyping analysis can be now utilised to preclinically evaluate the effects of potential RTT treatments. This review summarizes the different results achieved in this research field taking into account different key targets identified to ameliorate RTT phenotype in mouse models, including those not directly downstream of MeCP2 and those limited to the early phases of postnatal development. This article is part of the Special Issue entitled 'Neurodevelopmental Disorders'.
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Affiliation(s)
- Laura Ricceri
- Section of Neurotoxicology and Neuroendocrinology, Dept. Cell Biology and Neurosciences, Istituto Superiore di Sanità, Viale Regina Elena, 299, I-00161 Roma, Italy
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