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Kalani L, Kim BH, de Chavez AR, Roemer A, Mikhailov A, Merritt JK, Good KV, Chow RL, Delaney KR, Hendzel MJ, Zhou Z, Neul JL, Vincent JB, Ausió J. Testing the PEST hypothesis using relevant Rett mutations in MeCP2 E1 and E2 isoforms. Hum Mol Genet 2024:ddae119. [PMID: 39137370 DOI: 10.1093/hmg/ddae119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2024] [Revised: 07/19/2024] [Accepted: 08/07/2024] [Indexed: 08/15/2024] Open
Abstract
Mutations in methyl-CpG binding protein 2 (MeCP2), such as the T158M, P152R, R294X, and R306C mutations, are responsible for most Rett syndrome (RTT) cases. These mutations often result in altered protein expression that appears to correlate with changes in the nuclear size; however, the molecular details of these observations are poorly understood. Using a C2C12 cellular system expressing human MeCP2-E1 isoform as well as mouse models expressing these mutations, we show that T158M and P152R result in a decrease in MeCP2 protein, whereas R306C has a milder variation, and R294X resulted in an overall 2.5 to 3 fold increase. We also explored the potential involvement of the MeCP2 PEST domains in the proteasome-mediated regulation of MeCP2. Finally, we used the R294X mutant to gain further insight into the controversial competition between MeCP2 and histone H1 in the chromatin context. Interestingly, in R294X, MeCP2 E1 and E2 isoforms were differently affected, where the E1 isoform contributes to much of the overall protein increase observed, while E2 decreases by half. The modes of MeCP2 regulation, thus, appear to be differently regulated in the two isoforms.
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Affiliation(s)
- Ladan Kalani
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Bo-Hyun Kim
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Alberto Ruiz de Chavez
- Department of Biology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Anastasia Roemer
- Departments of Oncology and Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, 11560 University Ave, Edmonton, AB T6G 2H7, Canada
| | - Anna Mikhailov
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada
| | - Jonathan K Merritt
- Vanderbilt Kennedy Center, Departments of Pediatrics, Pharmacology, and Special Education, Vanderbilt University Medical Center and Vanderbilt University, 1211 Medical Center Dr, Nashville, TN 37232, United States
| | - Katrina V Good
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada
| | - Robert L Chow
- Department of Biology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Kerry R Delaney
- Department of Biology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Michael J Hendzel
- Departments of Oncology and Cell Biology, Faculty of Medicine and Dentistry, University of Alberta, 11560 University Ave, Edmonton, AB T6G 2H7, Canada
| | - Zhaolan Zhou
- Department of Genetics, Epigenetics Institute, University of Pennsylvania Perelman School of Medicine, 3400 Civic Center Blvd, Philadelphia, PA 19104, United States
| | - Jeffrey L Neul
- Vanderbilt Kennedy Center, Departments of Pediatrics, Pharmacology, and Special Education, Vanderbilt University Medical Center and Vanderbilt University, 1211 Medical Center Dr, Nashville, TN 37232, United States
| | - John B Vincent
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, 27 King's College Cir, Toronto, ON M5S 1A8, Canada
- Department of Psychiatry, University of Toronto, 27 King College Cir, Toronto, ON M5T 1R8, Canada
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
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Kalani L, Kim BH, Vincent JB, Ausió J. MeCP2 ubiquitination and sumoylation, in search of a function†. Hum Mol Genet 2023; 33:1-11. [PMID: 37694858 DOI: 10.1093/hmg/ddad150] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/12/2023] Open
Abstract
MeCP2 (Methyl CpG binding protein 2) is an intrinsically disordered protein that binds to methylated genome regions. The protein is a critical transcriptional regulator of the brain, and its mutations account for 95% of Rett syndrome (RTT) cases. Early studies of this neurodevelopmental disorder revealed a close connection with dysregulations of the ubiquitin system (UbS), notably as related to UBE3A, a ubiquitin ligase involved in the proteasome-mediated degradation of proteins. MeCP2 undergoes numerous post-translational modifications (PTMs), including ubiquitination and sumoylation, which, in addition to the potential functional outcomes of their monomeric forms in gene regulation and synaptic plasticity, in their polymeric organization, these modifications play a critical role in proteasomal degradation. UbS-mediated proteasomal degradation is crucial in maintaining MeCP2 homeostasis for proper function and is involved in decreasing MeCP2 in some RTT-causing mutations. However, regardless of all these connections to UbS, the molecular details involved in the signaling of MeCP2 for its targeting by the ubiquitin-proteasome system (UPS) and the functional roles of monomeric MeCP2 ubiquitination and sumoylation remain largely unexplored and are the focus of this review.
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Affiliation(s)
- Ladan Kalani
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - Bo-Hyun Kim
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
| | - John B Vincent
- Molecular Neuropsychiatry & Development (MiND) Lab, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, 250 College St, Toronto, ON M5T 1R8, Canada
- Institute of Medical Science, University of Toronto, 27 King's College Cir, Toronto, ON M5S 1A8, Canada
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, 3800 Finnerty Rd, Victoria, BC V8W 2Y2, Canada
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Good KV, Vincent JB, Ausió J. MeCP2: The Genetic Driver of Rett Syndrome Epigenetics. Front Genet 2021; 12:620859. [PMID: 33552148 PMCID: PMC7859524 DOI: 10.3389/fgene.2021.620859] [Citation(s) in RCA: 61] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Accepted: 01/05/2021] [Indexed: 12/24/2022] Open
Abstract
Mutations in methyl CpG binding protein 2 (MeCP2) are the major cause of Rett syndrome (RTT), a rare neurodevelopmental disorder with a notable period of developmental regression following apparently normal initial development. Such MeCP2 alterations often result in changes to DNA binding and chromatin clustering ability, and in the stability of this protein. Among other functions, MeCP2 binds to methylated genomic DNA, which represents an important epigenetic mark with broad physiological implications, including neuronal development. In this review, we will summarize the genetic foundations behind RTT, and the variable degrees of protein stability exhibited by MeCP2 and its mutated versions. Also, past and emerging relationships that MeCP2 has with mRNA splicing, miRNA processing, and other non-coding RNAs (ncRNA) will be explored, and we suggest that these molecules could be missing links in understanding the epigenetic consequences incurred from genetic ablation of this important chromatin modifier. Importantly, although MeCP2 is highly expressed in the brain, where it has been most extensively studied, the role of this protein and its alterations in other tissues cannot be ignored and will also be discussed. Finally, the additional complexity to RTT pathology introduced by structural and functional implications of the two MeCP2 isoforms (MeCP2-E1 and MeCP2-E2) will be described. Epigenetic therapeutics are gaining clinical popularity, yet treatment for Rett syndrome is more complicated than would be anticipated for a purely epigenetic disorder, which should be taken into account in future clinical contexts.
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Affiliation(s)
- Katrina V. Good
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
| | - John B. Vincent
- Molecular Neuropsychiatry & Development (MiND) Lab, Centre for Addiction and Mental Health, Campbell Family Mental Health Research Institute, Toronto, ON, Canada
- Institute of Medical Science, University of Toronto, Toronto, ON, Canada
- Department of Psychiatry, University of Toronto, Toronto, ON, Canada
| | - Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC, Canada
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Sarfraz M, Afzal A, Khattak S, Saddozai UAK, Li HM, Zhang QQ, Madni A, Haleem KS, Duan SF, Wu DD, Ji SP, Ji XY. Multifaceted behavior of PEST sequence enriched nuclear proteins in cancer biology and role in gene therapy. J Cell Physiol 2020; 236:1658-1676. [PMID: 32841373 DOI: 10.1002/jcp.30011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 07/18/2020] [Accepted: 08/04/2020] [Indexed: 01/12/2023]
Abstract
The amino acid sequence enriched with proline (P), glutamic acid (E), serine (S), and threonine (T) (PEST) is a signal-transducing agent providing unique features to its substrate nuclear proteins (PEST-NPs). The PEST motif is responsible for particular posttranslational modifications (PTMs). These PTMs impart distinct properties to PEST-NPs that are responsible for their activation/inhibition, intracellular localization, and stability/degradation. PEST-NPs participate in cancer metabolism, immunity, and protein transcription as oncogenes or as tumor suppressors. Gene-based therapeutics are getting the attention of researchers because of their cell specificity. PEST-NPs are good targets to explore as cancer therapeutics. Insights into PTMs of PEST-NPs demonstrate that these proteins not only interact with each other but also recruit other proteins to/from their active site to promote/inhibit tumors. Thus, the role of PEST-NPs in cancer biology is multivariate. It is hard to obtain therapeutic objectives with single gene therapy. An especially designed combination gene therapy might be a promising strategy in cancer treatment. This review highlights the multifaceted behavior of PEST-NPs in cancer biology. We have summarized a number of studies to address the influence of structure and PEST-mediated PTMs on activation, localization, stability, and protein-protein interactions of PEST-NPs. We also recommend researchers to adopt a pragmatic approach in gene-based cancer therapy.
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Affiliation(s)
- Muhammad Sarfraz
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China.,Faculty of Pharmacy, The University of Lahore, Lahore, Punjab, Pakistan.,Kaifeng Municipal Key Laboratory of Cell Signal Transduction, Henan Provincial Engineering Centre for Tumor Molecular Medicine, Henan University, Kaifeng, Henan, China
| | - Attia Afzal
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China.,Faculty of Pharmacy, The University of Lahore, Lahore, Punjab, Pakistan
| | - Saadullah Khattak
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China
| | - Umair A K Saddozai
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China
| | - Hui-Min Li
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China.,Department of Histology and Embryology, Cell Signal Transduction Laboratory, School of Basic Medical Sciences, Bioinformatics Centre, Institute of Biomedical Informatics, Henan University, Kaifeng, Henan, China
| | - Qian-Qian Zhang
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China
| | - Asadullah Madni
- Faculty of Pharmacy and Alternative Medicine, The Islamia University of Bahawalpur, Bahawalpur, Punjab, Pakistan
| | - Kashif S Haleem
- Department of Microbiology, Hazara University, Mansehra, Pakistan
| | - Shao-Feng Duan
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China.,School of Pharmacy, Institute for Innovative Drug Design and Evaluation, Henan University, Kaifeng, Henan, China
| | - Dong-Dong Wu
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China.,School of Stomatology, Henan University, Kaifeng, Henan, China
| | - Shao-Ping Ji
- Kaifeng Municipal Key Laboratory of Cell Signal Transduction, Henan Provincial Engineering Centre for Tumor Molecular Medicine, Henan University, Kaifeng, Henan, China
| | - Xin-Ying Ji
- Henan International Joint Laboratory for Nuclear Protein Regulation & Kaifeng Key Laboratory of Infectious Diseases and Bio-safety, School of Basic Medical Sciences, Henan University College of Medicine, Kaifeng, Henan, China
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Gandaglia A, Brivio E, Carli S, Palmieri M, Bedogni F, Stefanelli G, Bergo A, Leva B, Cattaneo C, Pizzamiglio L, Cicerone M, Bianchi V, Kilstrup-Nielsen C, D’Annessa I, Di Marino D, D’Adamo P, Antonucci F, Frasca A, Landsberger N. A Novel Mecp2Y120D Knock-in Model Displays Similar Behavioral Traits But Distinct Molecular Features Compared to the Mecp2-Null Mouse Implying Precision Medicine for the Treatment of Rett Syndrome. Mol Neurobiol 2018; 56:4838-4854. [DOI: 10.1007/s12035-018-1412-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 10/24/2018] [Indexed: 10/27/2022]
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Ausió J. Role of MeCP2 in neurological disorders: current status and future perspectives. Epigenomics 2017; 10:5-8. [PMID: 29172690 DOI: 10.2217/epi-2017-0128] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Affiliation(s)
- Juan Ausió
- Department of Biochemistry & Microbiology, University of Victoria, Victoria, BC, V8W 3P6, Canada
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Abstract
This paper provides a brief introductory review of the most recent advances in our knowledge about the structural and functional aspects of two transcriptional regulators: MeCP2, a protein whose mutated forms are involved in Rett syndrome; and CTCF, a constitutive transcriptional insulator. This is followed by a description of the PTMs affecting these two proteins and an analysis of their known interacting partners. A special emphasis is placed on the recent studies connecting these two proteins, focusing on the still poorly understood potential structural and functional interactions between the two of them on the chromatin substrate. An overview is provided for some of the currently known genes that are dually regulated by these two proteins. Finally, a model is put forward to account for their possible involvement in their regulation of gene expression.
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Affiliation(s)
- Juan Ausió
- a Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6, Canada.,b Center for Biomedical Research, University of Victoria, Victoria, BC V8W 3N5, Canada
| | - Philippe T Georgel
- c Department of Biological Sciences, Marshall University, Huntington, WV 25755, USA.,d Cell Differentiation and Development Center, Marshall University, Huntington, WV 25755, USA
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Claveria-Gimeno R, Abian O, Velazquez-Campoy A, Ausió J. MeCP2… Nature’s Wonder Protein or Medicine’s Most Feared One? CURRENT GENETIC MEDICINE REPORTS 2016. [DOI: 10.1007/s40142-016-0107-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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9
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Williams AA, Mehler VJ, Mueller C, Vonhoff F, White R, Duch C. Apoptotic Activity of MeCP2 Is Enhanced by C-Terminal Truncating Mutations. PLoS One 2016; 11:e0159632. [PMID: 27442528 PMCID: PMC4956225 DOI: 10.1371/journal.pone.0159632] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2016] [Accepted: 07/05/2016] [Indexed: 11/22/2022] Open
Abstract
Methyl-CpG binding protein 2 (MeCP2) is a widely abundant, multifunctional protein most highly expressed in post-mitotic neurons. Mutations causing Rett syndrome and related neurodevelopmental disorders have been identified along the entire MECP2 locus, but symptoms vary depending on mutation type and location. C-terminal mutations are prevalent, but little is known about the function of the MeCP2 C-terminus. We employ the genetic efficiency of Drosophila to provide evidence that expression of p.Arg294* (more commonly identified as R294X), a human MECP2 E2 mutant allele causing truncation of the C-terminal domains, promotes apoptosis of identified neurons in vivo. We confirm this novel finding in HEK293T cells and then use Drosophila to map the region critical for neuronal apoptosis to a small sequence at the end of the C-terminal domain. In vitro studies in mammalian systems previously indicated a role of the MeCP2 E2 isoform in apoptosis, which is facilitated by phosphorylation at serine 80 (S80) and decreased by interactions with the forkhead protein FoxG1. We confirm the roles of S80 phosphorylation and forkhead domain transcription factors in affecting MeCP2-induced apoptosis in Drosophila in vivo, thus indicating mechanistic conservation between flies and mammalian cells. Our findings are consistent with a model in which C- and N-terminal interactions are required for healthy function of MeCP2.
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Affiliation(s)
- Alison A. Williams
- School of Life Sciences, Arizona State University, Tempe, Arizona, United States of America
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | - Vera J. Mehler
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
| | | | - Fernando Vonhoff
- Molecular, Cellular, and Developmental Biology Department, Yale University, New Haven, Connecticut, United States of America
| | - Robin White
- Institute of Physiology, University Medical Center, Mainz, Germany
| | - Carsten Duch
- Institute of Zoology- Neurobiology, Johannes Gutenberg University Mainz, Mainz, Germany
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Brain phosphorylation of MeCP2 at serine 164 is developmentally regulated and globally alters its chromatin association. Sci Rep 2016; 6:28295. [PMID: 27323888 PMCID: PMC4915018 DOI: 10.1038/srep28295] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Accepted: 06/01/2016] [Indexed: 12/31/2022] Open
Abstract
MeCP2 is a transcriptional regulator whose functional alterations are responsible for several autism spectrum and mental disorders. Post-translational modifications (PTMs), and particularly differential phosphorylation, modulate MeCP2 function in response to diverse stimuli. Understanding the detailed role of MeCP2 phosphorylation is thus instrumental to ascertain how MeCP2 integrates the environmental signals and directs its adaptive transcriptional responses. The evolutionarily conserved serine 164 (S164) was found phosphorylated in rodent brain but its functional role has remained uncharacterized. We show here that phosphorylation of S164 in brain is dynamically regulated during neuronal maturation. S164 phosphorylation highly impairs MeCP2 binding to DNA in vitro and largely affects its nucleosome binding and chromatin affinity in vivo. Strikingly, the chromatin-binding properties of the global MeCP2 appear also extensively altered during the course of brain maturation. Functional assays reveal that proper temporal regulation of S164 phosphorylation controls the ability of MeCP2 to regulate neuronal morphology. Altogether, our results support the hypothesis of a complex PTM-mediated functional regulation of MeCP2 potentially involving a still poorly characterized epigenetic code. Furthermore, they demonstrate the relevance of the Intervening Domain of MeCP2 for binding to DNA.
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11
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Kweon SM, Chi F, Higashiyama R, Lai K, Tsukamoto H. Wnt Pathway Stabilizes MeCP2 Protein to Repress PPAR-γ in Activation of Hepatic Stellate Cells. PLoS One 2016; 11:e0156111. [PMID: 27214381 PMCID: PMC4877088 DOI: 10.1371/journal.pone.0156111] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 05/09/2016] [Indexed: 12/12/2022] Open
Abstract
PPAR-γ is essential for differentiation of hepatic stellate cells (HSC), and its loss due to epigenetic repression by methyl-CpG binding protein 2 (MeCP2) causes HSC myofibroblastic activation mediated in part via Wnt pathway, the key cellular event in liver fibrosis. Decreased miR-132 was previously proposed to promote MeCP2 protein translation for Ppar-γ repression in activated HSC (aHSC). The present study aimed to test this notion and to better understand the mechanisms of MeCP2 upregulation in aHSC. MeCP2 protein is increased on day 3 to 7 as HSC become activated in primary culture on plastic, but this is accompanied by increased but not reduced miR-132 or miR-212 which is also expected to target MeCP2 due to its similar sequence with miR-132. The levels of these mRNAs are decreased 40~50% in aHSCs isolated from experimental cholestatic liver fibrosis but increased 6–8 fold in aHSC from hepatotoxic liver fibrosis in rats. Suppression of either or both of miR132 and miR212 with specific anti-miRNA oligonucleotides (anti-oligo), does not affect MeCP2 protein levels in aHSCs. The Wnt antagonist FJ9 which inhibits HSC activation, increases miR-132/miR-212, reduces MeCP2 and its enrichment at 5’ Ppar-γ promoter, and restores Ppar-γ expression but the anti-oligo do not prevent Ppar-γ upregulation. The pan-NADPH oxidase (NOX) inhibitor diphenyleneiodonium (DPI) also reduces both MeCP2 and stabilized non-(S33/S37/Thr41)-phospho β-catenin and reverts aHSC to quiescent cells but do not affect miR-132/miR-212 levels. Wnt antagonism with FJ9 increases MeCP2 protein degradation in cultured HSC, and FJ9-mediated loss of MeCP2 is rescued by leupeptin but not by proteasome and lysozome inhibitors. In conclusion, canonical Wnt pathway increases MeCP2 protein due to protein stability which in turn represses Ppar-γ and activates HSC.
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Affiliation(s)
- Soo-Mi Kweon
- Southern California Research Center for ALPD and Cirrhosis, Department of Pathology, University of Southern California, Los Angeles, California, United States of America
| | - Feng Chi
- Southern California Research Center for ALPD and Cirrhosis, Department of Pathology, University of Southern California, Los Angeles, California, United States of America
| | - Reiichi Higashiyama
- Southern California Research Center for ALPD and Cirrhosis, Department of Pathology, University of Southern California, Los Angeles, California, United States of America
| | - Keane Lai
- Southern California Research Center for ALPD and Cirrhosis, Department of Pathology, University of Southern California, Los Angeles, California, United States of America
| | - Hidekazu Tsukamoto
- Southern California Research Center for ALPD and Cirrhosis, Department of Pathology, University of Southern California, Los Angeles, California, United States of America
- Department of Veterans Affairs Greater Los Angeles Healthcare System, Los Angeles, California, United States of America
- * E-mail:
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12
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Ausió J. MeCP2 and the enigmatic organization of brain chromatin. Implications for depression and cocaine addiction. Clin Epigenetics 2016; 8:58. [PMID: 27213019 PMCID: PMC4875624 DOI: 10.1186/s13148-016-0214-5] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2016] [Accepted: 04/20/2016] [Indexed: 12/21/2022] Open
Abstract
Methyl CpG binding protein 2 (MeCP2) is a highly abundant chromosomal protein within the brain. It is hence not surprising that perturbations in its genome-wide distribution, and at particular loci within this tissue, can result in widespread neurological disorders that transcend the early implications of this protein in Rett syndrome (RTT). Yet, the details of its role and involvement in chromatin organization are still poorly understood. This paper focuses on what is known to date about all of this with special emphasis on the relation to different epigenetic modifications (DNA methylation, histone acetylation/ubiquitination, MeCP2 phosphorylation and miRNA). We showcase all of the above in two particular important neurological functional alterations in the brain: depression (major depressive disorder [MDD]) and cocaine addiction, both of which affect the MeCP2 homeostasis and result in significant changes in the overall levels of these epigenetic marks.
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Affiliation(s)
- Juan Ausió
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W 3P6 Canada
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13
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Bergo A, Strollo M, Gai M, Barbiero I, Stefanelli G, Sertic S, Cobolli Gigli C, Di Cunto F, Kilstrup-Nielsen C, Landsberger N. Methyl-CpG binding protein 2 (MeCP2) localizes at the centrosome and is required for proper mitotic spindle organization. J Biol Chem 2014; 290:3223-37. [PMID: 25527496 DOI: 10.1074/jbc.m114.608125] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Mutations in MECP2 cause a broad spectrum of neuropsychiatric disorders of which Rett syndrome represents the best defined condition. Both neuronal and non-neuronal functions of the methyl-binding protein underlie the related pathologies. Nowadays MeCP2 is recognized as a multifunctional protein that modulates its activity depending on its protein partners and posttranslational modifications. However, we are still missing a comprehensive understanding of all MeCP2 functions and their involvement in the related pathologies. The study of human mutations often offers the possibility of clarifying the functions of a protein. Therefore, we decided to characterize a novel MeCP2 phospho-isoform (Tyr-120) whose relevance was suggested by a Rett syndrome patient carrying a Y120D substitution possibly mimicking a constitutively phosphorylated state. Unexpectedly, we found MeCP2 and its Tyr-120 phospho-isoform enriched at the centrosome both in dividing and postmitotic cells. The molecular and functional connection of MeCP2 to the centrosome was further reinforced through cellular and biochemical approaches. We show that, similar to many centrosomal proteins, MeCP2 deficiency causes aberrant spindle geometry, prolonged mitosis, and defects in microtubule nucleation. Collectively, our data indicate a novel function of MeCP2 that might reconcile previous data regarding the role of MeCP2 in cell growth and cytoskeleton stability and that might be relevant to understand some aspects of MeCP2-related conditions. Furthermore, they link the Tyr-120 residue and its phosphorylation to cell division, prompting future studies on the relevance of Tyr-120 for cortical development.
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Affiliation(s)
- Anna Bergo
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy
| | - Marta Strollo
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy
| | - Marta Gai
- the Molecular Biotechnology Center, Department of Molecular Biotechnologies and Health Sciences, University of Turin, 10126 Turin, Italy
| | - Isabella Barbiero
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy
| | - Gilda Stefanelli
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy
| | - Sarah Sertic
- the Department of Life Sciences, University of Milan, 20133 Milan, Italy, and
| | - Clementina Cobolli Gigli
- the San Raffaele Rett Research Unit, Division of Neuroscience, San Raffaele Scientific Institute, 20132 Milan, Italy
| | - Ferdinando Di Cunto
- the Molecular Biotechnology Center, Department of Molecular Biotechnologies and Health Sciences, University of Turin, 10126 Turin, Italy
| | - Charlotte Kilstrup-Nielsen
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy
| | - Nicoletta Landsberger
- From the Department of Theoretical and Applied Sciences, Section of Biomedical Research, University of Insubria, 21052 Busto Arsizio, Italy, the San Raffaele Rett Research Unit, Division of Neuroscience, San Raffaele Scientific Institute, 20132 Milan, Italy
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Ausió J, Paz AMD, Esteller M. MeCP2: the long trip from a chromatin protein to neurological disorders. Trends Mol Med 2014; 20:487-98. [DOI: 10.1016/j.molmed.2014.03.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2014] [Revised: 03/12/2014] [Accepted: 03/14/2014] [Indexed: 12/13/2022]
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Bellini E, Pavesi G, Barbiero I, Bergo A, Chandola C, Nawaz MS, Rusconi L, Stefanelli G, Strollo M, Valente MM, Kilstrup-Nielsen C, Landsberger N. MeCP2 post-translational modifications: a mechanism to control its involvement in synaptic plasticity and homeostasis? Front Cell Neurosci 2014; 8:236. [PMID: 25165434 PMCID: PMC4131190 DOI: 10.3389/fncel.2014.00236] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Accepted: 07/27/2014] [Indexed: 12/02/2022] Open
Abstract
Although Rett syndrome (RTT) represents one of the most frequent forms of severe intellectual disability in females worldwide, we still have an inadequate knowledge of the many roles played by MeCP2 (whose mutations are responsible for most cases of RTT) and their relevance for RTT pathobiology. Several studies support a role of MeCP2 in the regulation of synaptic plasticity and homeostasis. At the molecular level, MeCP2 is described as a repressor capable of inhibiting gene transcription through chromatin compaction. Indeed, it interacts with several chromatin remodeling factors, such as HDAC-containing complexes and ATRX. Other studies have inferred that MeCP2 functions also as an activator; a role in regulating mRNA splicing and in modulating protein synthesis has also been proposed. Further, MeCP2 avidly binds both 5-methyl- and 5-hydroxymethyl-cytosine. Recent evidence suggests that it is the highly disorganized structure of MeCP2, together with its post-translational modifications (PTMs) that generate and regulate this functional versatility. Indeed, several reports have demonstrated that differential phosphorylation of MeCP2 is a key mechanism by which the methyl binding protein modulates its affinity for its partners, gene expression and cellular adaptations to stimuli and neuronal plasticity. As logic consequence, generation of phospho-defective Mecp2 knock-in mice has permitted associating alterations in neuronal morphology, circuit formation, and mouse behavioral phenotypes with specific phosphorylation events. MeCP2 undergoes various other PTMs, including acetylation, ubiquitination and sumoylation, whose functional roles remain largely unexplored. These results, together with the genome-wide distribution of MeCP2 and its capability to substitute histone H1, recall the complex regulation of histones and suggest the relevance of quickly gaining a deeper comprehension of MeCP2 PTMs, the respective writers and readers and the consequent functional outcomes.
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Affiliation(s)
- Elisa Bellini
- Division of Neuroscience, San Raffaele Rett Research Center, San Raffaele Scientific Institute Milan, Italy
| | - Giulio Pavesi
- Department of Biosciences, University of Milan Milan, Italy
| | - Isabella Barbiero
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Anna Bergo
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Chetan Chandola
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Mohammad S Nawaz
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Laura Rusconi
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Gilda Stefanelli
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Marta Strollo
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Maria M Valente
- Division of Neuroscience, San Raffaele Rett Research Center, San Raffaele Scientific Institute Milan, Italy
| | - Charlotte Kilstrup-Nielsen
- Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
| | - Nicoletta Landsberger
- Division of Neuroscience, San Raffaele Rett Research Center, San Raffaele Scientific Institute Milan, Italy ; Section of Biomedical Research, Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretic and Applied Sciences, University of Insubria Busto Arsizio, Italy
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Abstract
Rett syndrome (RTT) is a severe and progressive neurological disorder, which mainly affects young females. Mutations of the methyl-CpG binding protein 2 (MECP2) gene are the most prevalent cause of classical RTT cases. MECP2 mutations or altered expression are also associated with a spectrum of neurodevelopmental disorders such as autism spectrum disorders with recent links to fetal alcohol spectrum disorders. Collectively, MeCP2 relation to these neurodevelopmental disorders highlights the importance of understanding the molecular mechanisms by which MeCP2 impacts brain development, mental conditions, and compromised brain function. Since MECP2 mutations were discovered to be the primary cause of RTT, a significant progress has been made in the MeCP2 research, with respect to the expression, function and regulation of MeCP2 in the brain and its contribution in RTT pathogenesis. To date, there have been intensive efforts in designing effective therapeutic strategies for RTT benefiting from mouse models and cells collected from RTT patients. Despite significant progress in MeCP2 research over the last few decades, there is still a knowledge gap between the in vitro and in vivo research findings and translating these findings into effective therapeutic interventions in human RTT patients. In this review, we will provide a synopsis of Rett syndrome as a severe neurological disorder and will discuss the role of MeCP2 in RTT pathophysiology.
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Bedogni F, Rossi RL, Galli F, Cobolli Gigli C, Gandaglia A, Kilstrup-Nielsen C, Landsberger N. Rett syndrome and the urge of novel approaches to study MeCP2 functions and mechanisms of action. Neurosci Biobehav Rev 2014; 46 Pt 2:187-201. [PMID: 24594195 DOI: 10.1016/j.neubiorev.2014.01.011] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 10/25/2013] [Accepted: 01/21/2014] [Indexed: 10/25/2022]
Abstract
Rett syndrome (RTT) is a devastating genetic disorder that worldwide represents the most common genetic cause of severe intellectual disability in females. Most cases are caused by mutations in the X-linked MECP2 gene. Several recent studies have demonstrated that RTT mimicking animal models do not develop an irreversible condition and phenotypic rescue is possible. However, no cure for RTT has been identified so far, and patients are only given symptomatic and supportive treatments. The development of clinical applications imposes a more comprehensive knowledge of MeCP2 functional role(s) and their relevance for RTT pathobiology. Herein, we thoroughly survey the knowledge about MeCP2 structure and functions, highlighting the necessity of identifying more functional domains and the value of molecular genetics. Given that, in our opinion, RTT ultimately is generated by perturbations in gene transcription and so far no genes/pathways have been consistently linked to a dysfunctional MeCP2, we have used higher-level bioinformatic analyses to identify commonly deregulated mechanisms in MeCP2-defective samples. In this review we present our results and discuss the possible value of the utilized approach.
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Affiliation(s)
- Francesco Bedogni
- San Raffaele Rett Research Center, Division of Neuroscience, San Raffaele Scientific Institute, Milan 20132, Italy; Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretical and Applied Sciences, Division of Biomedical Research, University of Insubria, Busto Arsizio 21052, Italy
| | - Riccardo L Rossi
- Fondazione Istituto Nazionale Genetica Molecolare, Milan 20122, Italy
| | - Francesco Galli
- San Raffaele Rett Research Center, Division of Neuroscience, San Raffaele Scientific Institute, Milan 20132, Italy
| | - Clementina Cobolli Gigli
- San Raffaele Rett Research Center, Division of Neuroscience, San Raffaele Scientific Institute, Milan 20132, Italy; Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretical and Applied Sciences, Division of Biomedical Research, University of Insubria, Busto Arsizio 21052, Italy
| | - Anna Gandaglia
- San Raffaele Rett Research Center, Division of Neuroscience, San Raffaele Scientific Institute, Milan 20132, Italy; Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretical and Applied Sciences, Division of Biomedical Research, University of Insubria, Busto Arsizio 21052, Italy
| | - Charlotte Kilstrup-Nielsen
- Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretical and Applied Sciences, Division of Biomedical Research, University of Insubria, Busto Arsizio 21052, Italy
| | - Nicoletta Landsberger
- San Raffaele Rett Research Center, Division of Neuroscience, San Raffaele Scientific Institute, Milan 20132, Italy; Laboratory of Genetic and Epigenetic Control of Gene Expression, Department of Theoretical and Applied Sciences, Division of Biomedical Research, University of Insubria, Busto Arsizio 21052, Italy.
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Stuss DP, Cheema M, Ng MK, Martinez de Paz A, Williamson B, Missiaen K, Cosman JD, McPhee D, Esteller M, Hendzel M, Delaney K, Ausió J. Impaired in vivo binding of MeCP2 to chromatin in the absence of its DNA methyl-binding domain. Nucleic Acids Res 2013; 41:4888-900. [PMID: 23558747 PMCID: PMC3643609 DOI: 10.1093/nar/gkt213] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
MeCP2 is a methyl-CpG-binding protein that is a main component of brain chromatin in vertebrates. In vitro studies have determined that in addition to its specific methyl-CpG-binding domain (MBD) MeCP2 also has several chromatin association domains. However, the specific interactions of MeCP2 with methylated or non-methylated chromatin regions and the structural characteristics of the resulting DNA associations in vivo remain poorly understood. We analysed the role of the MBD in MeCP2–chromatin associations in vivo using an MeCP2 mutant Rett syndrome mouse model (Mecp2tm1.1Jae) in which exon 3 deletion results in an N-terminal truncation of the protein, including most of the MBD. Our results show that in mutant mice, the truncated form of MeCP2 (ΔMeCP2) is expressed in different regions of the brain and liver, albeit at 50% of its wild-type (wt) counterpart. In contrast to the punctate nuclear distribution characteristic of wt MeCP2, ΔMeCP2 exhibits both diffuse nuclear localization and a substantial retention in the cytoplasm, suggesting a dysfunction of nuclear transport. In mutant brain tissue, neuronal nuclei are smaller, and ΔMeCP2 chromatin is digested faster by nucleases, producing a characteristic nuclease-resistant dinucleosome. Although a fraction of ΔMeCP2 is found associated with nucleosomes, its interaction with chromatin is transient and weak. Thus, our results unequivocally demonstrate that in vivo the MBD of MeCP2 together with its adjacent region in the N-terminal domain are critical for the proper interaction of the protein with chromatin, which cannot be replaced by any other of its protein domains.
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Affiliation(s)
- David P Stuss
- Department of Biology, University of Victoria, British Columbia, V8W 2Y2, Canada
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Lee SH, Kim IJ, Kim JG, Park JS, Kim YS, Yamaguchi M, Kim CM, Yoo MA. Regulation of intestinal stem cell proliferation by human methyl-CpG-binding protein-2 in Drosophila. Cell Struct Funct 2011; 36:197-208. [PMID: 21979236 DOI: 10.1247/csf.11027] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Recent studies have suggested the involvement of epigenetic factors such as methyl-CpG-binding protein-2 (MeCP2) in tumorigenesis. In addition, cancer may represent a stem cell-based disease, suggesting that understanding of stem cell regulation could provide valuable insights into the mechanisms of tumorigenesis. However, the function of epigenetic factors in stem cell regulation in adult tissues remains poorly understood. In the present study, we investigated the role of human MeCP2 (hMeCP2), a bridge factor linked to DNA modification and histone modification, in stem cell proliferation using adult Drosophila midgut, which appears to be an excellent model system to study stem cell biology. Results show that enterocyte (EC)-specific expression of hMeCP2 in adult midgut using an exogenous GAL4/UAS expression system induced intestinal stem cell (ISC) proliferation marked by staining with anti-phospho-histone H3 antibody and BrdU incorporation assays. In addition, hMeCP2 expression in ECs activated extracellular stress-response kinase signals in ISCs. Furthermore, expression of hMeCP2 modulated the distribution of heterochromatin protein-1 in ECs. Our data suggests the hypothesis that the expression of hMeCP2 in differentiated ECs stimulates ISC proliferation, implying a role of MeCP2 as a stem cell regulator.
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Affiliation(s)
- Shin-Hae Lee
- Department of Molecular Biology, College of Natural Science, Pusan National University, Busan, Republic of Korea
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Thambirajah AA, Ausió J. A moment's pause: putative nucleosome-based influences on MeCP2 regulation. Biochem Cell Biol 2010; 87:791-8. [PMID: 19898528 DOI: 10.1139/o09-054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
There has been a hotbed of activity surrounding MeCP2 research in the past number of years. Despite better characterizing the functions and nature of this protein, it has become abundantly clear that MeCP2 is involved in far more complex activities than perhaps initially anticipated. Recent publications have shown that MeCP2 is dynamically post-translationally modified, and it is possible that these marks permit MeCP2 to inhabit very diverse chromatin environments. It is also of interest to consider how nucleosome composition differs in these varying chromatin regions, and how the chromatin template itself contributes to diversifying the regulatory roles of MeCP2. These will be critical points to examine when seeking to understand how MeCP2 behaviour differentiates in tissues other than the brain. By understanding the chromatin and (or) tissue context in which MeCP2 interacts, it may be possible to discern the specific etiology of diseases linked to MeCP2 dysfunction.
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Affiliation(s)
- Anita A Thambirajah
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BC V8W3P6, Canada
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Beck IME, Vanden Berghe W, Vermeulen L, Yamamoto KR, Haegeman G, De Bosscher K. Crosstalk in inflammation: the interplay of glucocorticoid receptor-based mechanisms and kinases and phosphatases. Endocr Rev 2009; 30:830-82. [PMID: 19890091 PMCID: PMC2818158 DOI: 10.1210/er.2009-0013] [Citation(s) in RCA: 214] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 08/18/2009] [Indexed: 12/20/2022]
Abstract
Glucocorticoids (GCs) are steroidal ligands for the GC receptor (GR), which can function as a ligand-activated transcription factor. These steroidal ligands and derivatives thereof are the first line of treatment in a vast array of inflammatory diseases. However, due to the general surge of side effects associated with long-term use of GCs and the potential problem of GC resistance in some patients, the scientific world continues to search for a better understanding of the GC-mediated antiinflammatory mechanisms. The reversible phosphomodification of various mediators in the inflammatory process plays a key role in modulating and fine-tuning the sensitivity, longevity, and intensity of the inflammatory response. As such, the antiinflammatory GCs can modulate the activity and/or expression of various kinases and phosphatases, thus affecting the signaling efficacy toward the propagation of proinflammatory gene expression and proinflammatory gene mRNA stability. Conversely, phosphorylation of GR can affect GR ligand- and DNA-binding affinity, mobility, and cofactor recruitment, culminating in altered transactivation and transrepression capabilities of GR, and consequently leading to a modified antiinflammatory potential. Recently, new roles for kinases and phosphatases have been described in GR-based antiinflammatory mechanisms. Moreover, kinase inhibitors have become increasingly important as antiinflammatory tools, not only for research but also for therapeutic purposes. In light of these developments, we aim to illuminate the integrated interplay between GR signaling and its correlating kinases and phosphatases in the context of the clinically important combat of inflammation, giving attention to implications on GC-mediated side effects and therapy resistance.
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Affiliation(s)
- Ilse M E Beck
- Laboratory of Eukaryotic Gene Expression and Signal Transduction, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium
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