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Ortega-Alarcon D, Claveria-Gimeno R, Vega S, Kalani L, Jorge-Torres OC, Esteller M, Ausio J, Abian O, Velazquez-Campoy A. Extending MeCP2 interactome: canonical nucleosomal histones interact with MeCP2. Nucleic Acids Res 2024; 52:3636-3653. [PMID: 38321951 DOI: 10.1093/nar/gkae051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Revised: 01/12/2024] [Accepted: 01/16/2024] [Indexed: 02/08/2024] Open
Abstract
MeCP2 is a general regulator of transcription involved in the repression/activation of genes depending on the local epigenetic context. It acts as a chromatin regulator and binds with exquisite specificity to gene promoters. The set of epigenetic marks recognized by MeCP2 has been already established (mainly, cytosine modifications in CpG and CpA), as well as many of the constituents of its interactome. We unveil a new set of interactions for MeCP2 with the four canonical nucleosomal histones. MeCP2 interacts with high affinity with H2A, H2B, H3 and H4. In addition, Rett syndrome associated mutations in MeCP2 and histone epigenetic marks modulate these interactions. Given the abundance and the structural/functional relevance of histones and their involvement in epigenetic regulation, this new set of interactions and its modulating elements provide a new addition to the 'alphabet' for this epigenetic reader.
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Affiliation(s)
- David Ortega-Alarcon
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
| | | | - Sonia Vega
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
| | - Ladan Kalani
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BCV8W 2Y2, Canada
| | - Olga C Jorge-Torres
- Josep Carreras Leukaemia Research Institute (IJC), 08916 Badalona, Barcelona, Spain
| | - Manel Esteller
- Josep Carreras Leukaemia Research Institute (IJC), 08916 Badalona, Barcelona, Spain
- Centro de Investigación Biomédica en Red Cáncer (CIBERONC), 28029 Madrid, Spain
- Institucio Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain
- Physiological Sciences Department, School of Medicine and Health Sciences, University of Barcelona (UB), 08907 l'Hospitalet de Llobregat, Barcelona, Spain
| | - Juan Ausio
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, BCV8W 2Y2, Canada
| | - Olga Abian
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Centro de Investigación Biomédica en Red en el Área Temática de Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain
| | - Adrian Velazquez-Campoy
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Unit GBsC-CSIC-BIFI, Universidad de Zaragoza, 50018 Zaragoza, Spain
- Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
- Centro de Investigación Biomédica en Red en el Área Temática de Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain
- Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain
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Wang Q, Luo S, Xiong D, Xu X, Zhao X, Duan L. Quantitative investigation of the effects of DNA modifications and protein mutations on MeCP2-MBD-DNA interactions. Int J Biol Macromol 2023; 247:125690. [PMID: 37423448 DOI: 10.1016/j.ijbiomac.2023.125690] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/27/2023] [Accepted: 07/02/2023] [Indexed: 07/11/2023]
Abstract
DNA methylation as an important epigenetic marker, has gained attention for the significance of three oxidative modifications (hydroxymethyl-C (hmC), formyl-C (fC), and carboxyl-C (caC)). Mutations occurring in the methyl-CpG-binding domain (MBD) of MeCP2 result in Rett. However, uncertainties persist regarding DNA modification and MBD mutation-induced interaction changes. Here, molecular dynamics simulations were used to investigate the underlying mechanisms behind changes due to different modifications of DNA and MBD mutations. Alanine scanning combined with the interaction entropy method was employed to accurately evaluate the binding free energy. The results show that MBD has the strongest binding ability for mCDNA, followed by caC, hmC, and fCDNA, with the weakest binding ability observed for CDNA. Further analysis revealed that mC modification induces DNA bending, causing residues R91 and R162 closer to the DNA. This proximity enhances van der Waals and electrostatic interactions. Conversely, the caC/hmC and fC modifications lead to two loop regions (near K112 and K130) closer to DNA, respectively. Furthermore, DNA modifications promote the formation of stable hydrogen bond networks, however mutations in the MBD significantly reduce the binding free energy. This study provides detailed insight into the effects of DNA modifications and MBD mutations on binding ability. It emphasizes the necessity for research and development of targeted Rett compounds that induce conformational compatibility between MBD and DNA, enhancing the stability and strength of their interactions.
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Affiliation(s)
- Qihang Wang
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Song Luo
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Danyang Xiong
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Xiaole Xu
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Xiaoyu Zhao
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China
| | - Lili Duan
- School of Physics and Electronics, Shandong Normal University, Jinan 250014, China.
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Li Puma DD, Colussi C, Bandiera B, Puliatti G, Rinaudo M, Cocco S, Paciello F, Re A, Ripoli C, De Chiara G, Bertozzi A, Palamara AT, Piacentini R, Grassi C. Interleukin 1β triggers synaptic and memory deficits in Herpes simplex virus type-1-infected mice by downregulating the expression of synaptic plasticity-related genes via the epigenetic MeCP2/HDAC4 complex. Cell Mol Life Sci 2023; 80:172. [PMID: 37261502 DOI: 10.1007/s00018-023-04817-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/17/2023] [Accepted: 05/20/2023] [Indexed: 06/02/2023]
Abstract
Extensive research provides evidence that neuroinflammation underlies numerous brain disorders. However, the molecular mechanisms by which inflammatory mediators determine synaptic and cognitive dysfunction occurring in neurodegenerative diseases (e.g., Alzheimer's disease) are far from being fully understood. Here we investigated the role of interleukin 1β (IL-1β), and the molecular cascade downstream the activation of its receptor, to the synaptic dysfunction occurring in the mouse model of multiple Herpes simplex virus type-1 (HSV-1) reactivations within the brain. These mice are characterized by neuroinflammation and memory deficits associated with a progressive accumulation of neurodegenerative hallmarks (e.g., amyloid-β protein and tau hyperphosphorylation). Here we show that mice undergone two HSV-1 reactivations in the brain exhibited increased levels of IL-1β along with significant alterations of: (1) cognitive performances; (2) hippocampal long-term potentiation; (3) expression synaptic-related genes and pre- and post-synaptic proteins; (4) dendritic spine density and morphology. These effects correlated with activation of the epigenetic repressor MeCP2 that, in association with HDAC4, affected the expression of synaptic plasticity-related genes. Specifically, in response to HSV-1 infection, HDAC4 accumulated in the nucleus and promoted MeCP2 SUMOylation that is a post-translational modification critically affecting the repressive activity of MeCP2. The blockade of IL-1 receptors by the specific antagonist Anakinra prevented the MeCP2 increase and the consequent downregulation of gene expression along with rescuing structural and functional indices of neurodegeneration. Collectively, our findings provide novel mechanistic evidence on the role played by HSV-1-activated IL-1β signaling pathways in synaptic deficits leading to cognitive impairment.
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Affiliation(s)
- Domenica Donatella Li Puma
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
| | - Claudia Colussi
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
- Department of Engineering, Istituto di Analisi dei Sistemi ed Informatica "Antonio Ruberti", National Research Council, 00185, Rome, Italy
| | - Bruno Bandiera
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Giulia Puliatti
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Marco Rinaudo
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
| | - Sara Cocco
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Fabiola Paciello
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
| | - Agnese Re
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
| | - Cristian Ripoli
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
| | - Giovanna De Chiara
- Institute of Translational Pharmacology, National Research Council (CNR), 00133, Rome, Italy
| | - Alessia Bertozzi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Department of Engineering, Istituto di Analisi dei Sistemi ed Informatica "Antonio Ruberti", National Research Council, 00185, Rome, Italy
| | - Anna Teresa Palamara
- Department of Infectious Diseases, Istituto Superiore Di Sanità, 00161, Rome, Italy
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Laboratory Affiliated to Istituto Pasteur Italia-Cenci Bolognetti Foundation, 00185, Rome, Italy
| | - Roberto Piacentini
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy.
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy.
| | - Claudio Grassi
- Department of Neuroscience, Università Cattolica del Sacro Cuore, 00168, Rome, Italy
- Fondazione Policlinico Universitario A. Gemelli IRCCS, 00168, Rome, Italy
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Li Y, Qin J, Chen M, Sun N, Tan F, Zhang H, Zou Y, Uversky VN, Liu Y. The Moonlighting Function of Soybean Disordered Methyl-CpG-Binding Domain 10c Protein. Int J Mol Sci 2023; 24:ijms24108677. [PMID: 37240035 DOI: 10.3390/ijms24108677] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Revised: 05/04/2023] [Accepted: 05/10/2023] [Indexed: 05/28/2023] Open
Abstract
Intrinsically disordered proteins (IDPs) are multifunctional due to their ability to adopt different structures depending on the local conditions. The intrinsically disordered regions of methyl-CpG-binding domain (MBD) proteins play important roles in regulating growth and development by interpreting DNA methylation patterns. However, whether MBDs have a stress-protective function is far from clear. In this paper, soybean GmMBD10c protein, which contains an MBD and is conserved in Leguminosae, was predicted to be located in the nucleus. It was found to be partially disordered by bioinformatic prediction, circular dichroism and a nuclear magnetic resonance spectral analysis. The enzyme activity assay and SDS-PAGE results showed that GmMBD10c can protect lactate dehydrogenase and a broad range of other proteins from misfolding and aggregation induced by the freeze-thaw process and heat stress, respectively. Furthermore, overexpression of GmMBD10c enhanced the salt tolerance of Escherichia coli. These data validate that GmMBD10c is a moonlighting protein with multiple functions.
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Affiliation(s)
- Yanling Li
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Jiawei Qin
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Menglu Chen
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Nan Sun
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Fangmei Tan
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Hua Zhang
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
| | - Yongdong Zou
- The Instrumental Analysis Center of Shenzhen University, Shenzhen University, Shenzhen 518060, China
| | - Vladimir N Uversky
- Department of Molecular Medicine and USF Health Byrd Alzheimer's Research Institute, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Yun Liu
- Guangdong Provincial Key Laboratory for Plant Epigenetics, Shenzhen Key Laboratory of Microbial Genetic Engineering, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen 518060, China
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Ortega-Alarcon D, Claveria-Gimeno R, Vega S, Jorge-Torres OC, Esteller M, Abian O, Velazquez-Campoy A. Unexpected thermodynamic signature for the interaction of hydroxymethylated DNA with MeCP2. Int J Biol Macromol 2023; 232:123373. [PMID: 36702223 DOI: 10.1016/j.ijbiomac.2023.123373] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/24/2023]
Abstract
Hydroxymethylated cytosine (5hmC) is a stable DNA epigenetic mark recognized by methyl-CpG binding protein 2 (MeCP2), which acts as a transcriptional regulator and a global chromatin-remodeling element. Because 5hmC triggers a gene regulation response markedly different from that produced by methylated cytosine (5mC), both modifications must affect DNA structure and/or DNA interaction with MeCP2 differently. MeCP2 is a six-domain intrinsically disordered protein (IDP) with two domains responsible for dsDNA binding: methyl-CpG binding domain (MBD) and intervening domain (ID). Here we report the detailed thermodynamic characterization of the interaction of hmCpG-DNA with MeCP2. We find that hmCpG-DNA interacts with MeCP2 in a distinctly different mode with a particular thermodynamic signature, compared to methylated or unmethylated DNA. In addition, we find evidence for Rett syndrome-associated mutations altering the interaction of MeCP2 with dsDNA in a cytosine modification-specific manner which may correlate with disease onset time and clinical severity score.
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Affiliation(s)
- David Ortega-Alarcon
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units GBsC-CSIC-BIFI and ICVV-CSIC-BIFI, Universidad de Zaragoza, Zaragoza 50018, Spain
| | - Rafael Claveria-Gimeno
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units GBsC-CSIC-BIFI and ICVV-CSIC-BIFI, Universidad de Zaragoza, Zaragoza 50018, Spain; Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain
| | - Sonia Vega
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units GBsC-CSIC-BIFI and ICVV-CSIC-BIFI, Universidad de Zaragoza, Zaragoza 50018, Spain
| | - Olga C Jorge-Torres
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, 08916 Barcelona, Spain
| | - Manel Esteller
- Josep Carreras Leukaemia Research Institute (IJC), Badalona, 08916 Barcelona, Spain; Centro de Investigación Biomédica en Red de Cáncer (CIBERONC), 28029 Madrid, Spain; Institucio Catalana de Recerca i Estudis Avançats (ICREA), 08010 Barcelona, Spain; Physiological Sciences Department, School of Medicine and Health Sciences, University of Barcelona (UB), l'Hospitalet de Llobregat, 08907 Barcelona, Spain
| | - Olga Abian
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units GBsC-CSIC-BIFI and ICVV-CSIC-BIFI, Universidad de Zaragoza, Zaragoza 50018, Spain; Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain; Centro de Investigación Biomédica en Red en el Área Temática de Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain.
| | - Adrian Velazquez-Campoy
- Institute of Biocomputation and Physics of Complex Systems (BIFI), Joint Units GBsC-CSIC-BIFI and ICVV-CSIC-BIFI, Universidad de Zaragoza, Zaragoza 50018, Spain; Instituto de Investigación Sanitaria Aragón (IIS Aragón), 50009 Zaragoza, Spain; Josep Carreras Leukaemia Research Institute (IJC), Badalona, 08916 Barcelona, Spain; Centro de Investigación Biomédica en Red en el Área Temática de Enfermedades Hepáticas y Digestivas (CIBERehd), 28029 Madrid, Spain; Departamento de Bioquímica y Biología Molecular y Celular, Universidad de Zaragoza, 50009 Zaragoza, Spain.
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Zhou X, Sun Z, Su X, Zheng K, Zou X, Zhang W. Ratiometric Detection of Ochratoxin A Using a Regenerable COF-Au-MB-Apt Signal Probe on a Thermal-Regulated Sensor Module. Anal Chem 2023; 95:1916-1923. [PMID: 36621809 DOI: 10.1021/acs.analchem.2c04031] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Ochratoxin A (OTA) frequently contaminates grains and consequently threatens human health. Herein, we develop a regenerable signal probe and apply it to a Au-based screen-printed electrode module (SPE) for OTA determination. The signal probe, containing a structural covalent organic framework, gold nanoparticles (AuNPs), indicative methylene blue (MB), and a highly selective aptamer, is synthesized with hydrothermal and self-assembly methods. The SPE is permanently functionalized with Prussian blue (PB), AuNPs, and semicomplementary ssDNA. The signal probe, absorbed onto this SPE via hybridization, is competitively expelled by OTA, providing a ratiometric readout of ΔIMB/IPB. Probe regeneration, to erase expired COF-Au-MB-Apt after each analysis, is established with the synergy of OTA-conducted Apt-ssDNA dissociation and on-chip thermal regulation. This advantage powerfully guarantees reduplicative analyses by avoiding irreversible Apt-OTA combination and accumulation on the sensing interface. Regenerations are performed in repetitive cycles (N = 7) with 98.5% reproduction efficiency, and IMB and IPB fluctuations are calculated as 1.45 and 1.12%. This method shows log-linear OTA response in a wide range from 0.2 pg/mL to 0.6 μg/mL, and the limit of detection is 0.12 pg/mL. During natural OTA determinations, recommended readouts match well with HPLC with less than 4.82% relative error.
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Affiliation(s)
- Xuan Zhou
- College of Photoelectric Engineering, Chongqing University, Chongqing 400044, China
- Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Zongbao Sun
- Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Xiaoyu Su
- Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Kaiyi Zheng
- Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Xiaobo Zou
- Department of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China
| | - Wen Zhang
- College of Photoelectric Engineering, Chongqing University, Chongqing 400044, China
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Ortega-Alarcon D, Claveria-Gimeno R, Vega S, Jorge-Torres OC, Esteller M, Abian O, Velazquez-Campoy A. Stabilization Effect of Intrinsically Disordered Regions on Multidomain Proteins: The Case of the Methyl-CpG Protein 2, MeCP2. Biomolecules 2021; 11:1216. [PMID: 34439881 DOI: 10.3390/biom11081216] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2021] [Revised: 08/04/2021] [Accepted: 08/13/2021] [Indexed: 12/14/2022] Open
Abstract
Intrinsic disorder plays an important functional role in proteins. Disordered regions are linked to posttranslational modifications, conformational switching, extra/intracellular trafficking, and allosteric control, among other phenomena. Disorder provides proteins with enhanced plasticity, resulting in a dynamic protein conformational/functional landscape, with well-structured and disordered regions displaying reciprocal, interdependent features. Although lacking well-defined conformation, disordered regions may affect the intrinsic stability and functional properties of ordered regions. MeCP2, methyl-CpG binding protein 2, is a multifunctional transcriptional regulator associated with neuronal development and maturation. MeCP2 multidomain structure makes it a prototype for multidomain, multifunctional, intrinsically disordered proteins (IDP). The methyl-binding domain (MBD) is one of the key domains in MeCP2, responsible for DNA recognition. It has been reported previously that the two disordered domains flanking MBD, the N-terminal domain (NTD) and the intervening domain (ID), increase the intrinsic stability of MBD against thermal denaturation. In order to prove unequivocally this stabilization effect, ruling out any artifactual result from monitoring the unfolding MBD with a local fluorescence probe (the single tryptophan in MBD) or from driving the protein unfolding by temperature, we have studied the MBD stability by differential scanning calorimetry (reporting on the global unfolding process) and chemical denaturation (altering intramolecular interactions by a different mechanism compared to thermal denaturation).
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