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Jafari SH, Lajevardi ZS, Zamani Fard MM, Jafari A, Naghavi S, Ravaei F, Taghavi SP, Mosadeghi K, Zarepour F, Mahjoubin-Tehran M, Rahimian N, Mirzaei H. Imaging Techniques and Biochemical Biomarkers: New Insights into Diagnosis of Pancreatic Cancer. Cell Biochem Biophys 2024:10.1007/s12013-024-01437-z. [PMID: 39026059 DOI: 10.1007/s12013-024-01437-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/12/2024] [Indexed: 07/20/2024]
Abstract
Pancreatic cancer (PaC) incidence is increasing, but our current screening and diagnostic strategies are not very effective. However, screening could be helpful in the case of PaC, as recent evidence shows that the disease progresses gradually. Unfortunately, there is no ideal screening method or program for detecting PaC in its early stages. Conventional imaging techniques, such as abdominal ultrasound, CT, MRI, and EUS, have not been successful in detecting early-stage PaC. On the other hand, biomarkers may be a more effective screening tool for PaC and have greater potential for further evaluation compared to imaging. Recent studies on biomarkers and artificial intelligence (AI)-enhanced imaging have shown promising results in the early diagnosis of PaC. In addition to proteins, non-coding RNAs are also being studied as potential biomarkers for PaC. This review consolidates the current literature on PaC screening modalities to provide an organized framework for future studies. While conventional imaging techniques have not been effective in detecting early-stage PaC, biomarkers and AI-enhanced imaging are promising avenues of research. Further studies on the use of biomarkers, particularly non-coding RNAs, in combination with imaging modalities may improve the accuracy of PaC screening and lead to earlier detection of this deadly disease.
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Affiliation(s)
- Seyed Hamed Jafari
- Medical Imaging Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
- Department of Radiology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Zahra Sadat Lajevardi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Mohammad Masoud Zamani Fard
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Ameneh Jafari
- Chronic Respiratory Diseases Research Center, NRITLD, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Soroush Naghavi
- Student Research Committee, Iran University of Medical Sciences, Tehran, Iran
| | - Fatemeh Ravaei
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Seyed Pouya Taghavi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Kimia Mosadeghi
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | - Fatemeh Zarepour
- School of Medicine, Kashan University of Medical Sciences, Kashan, Iran
- Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran
| | | | - Neda Rahimian
- Endocrine Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences (IUMS), Tehran, Iran; Department of Internal Medicine, School of Medicine, Firoozgar Hospital, Iran University of Medical Sciences, Tehran, Iran.
| | - Hamed Mirzaei
- Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran.
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Tan CW, Sim DY, Zhen Y, Tian H, Koh J, Roca X. PRPF40A induces inclusion of exons in GC-rich regions important for human myeloid cell differentiation. Nucleic Acids Res 2024:gkae557. [PMID: 38943321 DOI: 10.1093/nar/gkae557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Revised: 06/07/2024] [Accepted: 06/19/2024] [Indexed: 07/01/2024] Open
Abstract
We characterized the regulatory mechanisms and role in human myeloid cell survival and differentiation of PRPF40A, a splicing factor lacking a canonical RNA Binding Domain. Upon PRPF40A knockdown, HL-60 cells displayed increased cell death, decreased proliferation and slight differentiation phenotype with upregulation of immune activation genes. Suggestive of both redundant and specific functions, cell death but not proliferation was rescued by overexpression of its paralog PRPF40B. Transcriptomic analysis revealed the predominant role of PRPF40A as an activator of cassette exon inclusion of functionally relevant splicing events. Mechanistically, the exons exclusively upregulated by PRPF40A are flanked by short and GC-rich introns which tend to localize to nuclear speckles in the nucleus center. These PRPF40A regulatory features are shared with other splicing regulators such as SRRM2, SON, PCBP1/2, and to a lesser extent TRA2B and SRSF2, as a part of a functional network that regulates splicing partly via co-localization in the nucleus.
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Affiliation(s)
- Cheryl Weiqi Tan
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Donald Yuhui Sim
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Yashu Zhen
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Haobo Tian
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Jace Koh
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
| | - Xavier Roca
- School of Biological Sciences, Nanyang Technological University, 637551 Singapore
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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] [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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Tang G, Ding G, Wu G, Wang X, Wang T, Zou Q, Sun K, Wu J. Low expression of PRRG2 in kidney renal clear cell carcinoma: an immune infiltration-associated prognostic biomarker. Discov Oncol 2024; 15:9. [PMID: 38227081 DOI: 10.1007/s12672-024-00864-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 01/11/2024] [Indexed: 01/17/2024] Open
Abstract
OBJECTIVE This study aims to explore the prognostic significance of Proline-rich γ-carboxyglutamic acid protein 2 (PRRG2) in Kidney Renal Clear Cell Carcinoma (KIRC), a prevalent and deadly cancer, and its association with immune cell infiltration, a key strategy in developing effective biomarkers. METHODS The study meticulously elucidated the prognostic significance and potential role of PRRG2 in KIRC, correlating its expression with patient sex, age, metastasis, and pathological stage. Utilizing Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and Gene Set Enrichment Analysis (GSEA), the involvement of PRRG2 in immune response was investigated. The association between PRRG2 expression and immune cell infiltration was also scrutinized. Ultimately, cellular and tissue identity were confirmed via immunohistochemical staining and quantitative real-time PCR. RESULTS The study elucidates a notable decrease in PRRG2 expression in KIRC patients, correlating with demographic factors, metastasis, and pathological staging, and portending an unfavorable prognosis. Bioinformatic analyses underscore PRRG2's role in immune response, with its expression significantly tied to immune cell infiltration and marker expression. CONCLUSION PRRG2 may potentially impact prognosis in KIRC patients by regulating immune infiltration, thus rendering PRRG2 a promising candidate prognostic biomarker for KIRC-associated immune infiltration.
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Affiliation(s)
- Gonglin Tang
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Guixin Ding
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Gang Wu
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Xiaofeng Wang
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Tianqi Wang
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Qingsong Zou
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China
| | - Kai Sun
- Urology Department, Shandong Provincial Hospital, Shandong University, Jinan, 250021, China.
| | - Jitao Wu
- Department of Urology, The Affiliated Yantai Yuhuangding Hospital of Qingdao University, No. 20 East Yuhuangding Road, Yantai, 264000, Shandong, China.
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Díaz Casas A, Cordoba JJ, Ferrer BJ, Balakrishnan S, Wurm JE, Pastrana‐Ríos B, Chazin WJ. Binding by calmodulin is coupled to transient unfolding of the third FF domain of Prp40A. Protein Sci 2023; 32:e4606. [PMID: 36810829 PMCID: PMC10022492 DOI: 10.1002/pro.4606] [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: 11/22/2022] [Revised: 02/16/2023] [Accepted: 02/18/2023] [Indexed: 02/24/2023]
Abstract
Human pre-mRNA processing protein 40 homolog A (hPrp40A) is a splicing factor that interacts with the Huntington's disease protein huntingtin (Htt). Evidence has accumulated that both Htt and hPrp40A are modulated by the intracellular Ca2+ sensor calmodulin (CaM). Here we report characterization of the interaction of human CM with the third FF domain (FF3 ) of hPrp40A using calorimetric, fluorescence and structural approaches. Homology modeling, differential scanning calorimetry and small angle X-ray scattering (SAXS) data show FF3 forms a folded globular domain. CaM was found to bind FF3 in a Ca2+ -dependent manner with a 1:1 stoichiometry and a dissociation constant (Kd ) of 25 ± 3 μM at 25°C. NMR studies showed that both domains of CaM are engaged in binding and SAXS analysis of the FF3 -CaM complex revealed CaM occupies an extended configuration. Analysis of the FF3 sequence showed that the anchors for CaM binding must be buried in its hydrophobic core, suggesting that binding to CaM requires unfolding of FF3 . Trp anchors were proposed based on sequence analysis and confirmed by intrinsic Trp fluorescence of FF3 upon binding of CaM and substantial reductions in affinity for Trp-Ala FF3 mutants. The consensus model of the complex showed that binding to CaM binding occurs to an extended, non-globular state of the FF3 , consistent with coupling to transient unfolding of the domain. The implications of these results are discussed in the context of the complex interplay of Ca2+ signaling and Ca2+ sensor proteins in modulating Prp40A-Htt function.
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Affiliation(s)
- A. Díaz Casas
- Department of BiochemistryVanderbilt UniversityNashvilleTennesseeUSA
- Center for Structural BiologyVanderbilt UniversityNashvilleTennesseeUSA
- Present address:
Department of Natural SciencesPontifical Catholic University of Puerto RicoPoncePuerto RicoUSA
| | - J. J. Cordoba
- Department of BiochemistryVanderbilt UniversityNashvilleTennesseeUSA
- Center for Structural BiologyVanderbilt UniversityNashvilleTennesseeUSA
- Chemical and Physical Biology Graduate ProgramVanderbilt UniversityNashvilleTennesseeUSA
| | - B. J. Ferrer
- Department of BiochemistryVanderbilt UniversityNashvilleTennesseeUSA
- Center for Structural BiologyVanderbilt UniversityNashvilleTennesseeUSA
- Chemical and Physical Biology Graduate ProgramVanderbilt UniversityNashvilleTennesseeUSA
| | - S. Balakrishnan
- Department of BiochemistryVanderbilt UniversityNashvilleTennesseeUSA
- Center for Structural BiologyVanderbilt UniversityNashvilleTennesseeUSA
| | - J. E. Wurm
- Chemical and Physical Biology Graduate ProgramVanderbilt UniversityNashvilleTennesseeUSA
| | - B. Pastrana‐Ríos
- Department of ChemistryUniversity of Puerto Rico, Mayagüez CampusMayagüezPuerto RicoUSA
| | - W. J. Chazin
- Department of BiochemistryVanderbilt UniversityNashvilleTennesseeUSA
- Center for Structural BiologyVanderbilt UniversityNashvilleTennesseeUSA
- Chemical and Physical Biology Graduate ProgramVanderbilt UniversityNashvilleTennesseeUSA
- Department of ChemistryVanderbilt UniversityNashvilleTennesseeUSA
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6
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Jamal QMS, Alharbi AH. Molecular docking and dynamics studies of cigarette smoke carcinogens interacting with acetylcholinesterase and butyrylcholinesterase enzymes of the central nervous system. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:61972-61992. [PMID: 34382170 DOI: 10.1007/s11356-021-15269-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
The free radicals produced by cigarette smoking are responsible for tissue damage, heart and lung diseases, and carcinogenesis. The effect of tobacco on the central nervous system (CNS) has received increased attention nowadays in research. Therefore, to explore the molecular interaction of cigarette smoke carcinogens (CSC) 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanol (NNAL), 4-(methylnitrosamine)-1-(3-pyridyl)-1-butanone (NNK), and N'-nitrosonornicotine (NNN) with well-known targets of CNS-related disorders, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes, a cascade of the computational study was conducted including molecular docking and molecular dynamics simulations (MDS). The investigated results of NNAL+AChEcomplex, NNK+AChEcomplex, and NNK+BuChEcomplex based on intermolecular energies (∆G) were found to -8.57 kcal/mol, -8.21 kcal/mol, and -8.08 kcal/mol, respectively. MDS deviation and fluctuation plots of the NNAL and NNK interaction with AChE and BuChE have shown significant results. Further, Molecular Mechanics Poisson-Boltzmann Surface Area (MM-PBSA) results shown the best total binding energy (Binding∆G) -87.381 (+/-13.119) kJ/mol during NNK interaction with AChE. Our study suggests that CSC is well capable of altering the normal biomolecular mechanism of CNS; thus, obtained data could be useful to design extensive wet laboratory experimentation to know the effects of CSC on human CNS.
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Affiliation(s)
- Qazi Mohammad Sajid Jamal
- Department of Health Informatics, College of Public Health and Health Informatics, Qassim University, Al Bukayriyah, Saudi Arabia.
| | - Ali H Alharbi
- Department of Health Informatics, College of Public Health and Health Informatics, Qassim University, Al Bukayriyah, Saudi Arabia
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Chang KJ, Wu HY, Yarmishyn AA, Li CY, Hsiao YJ, Chi YC, Lo TC, Dai HJ, Yang YC, Liu DH, Hwang DK, Chen SJ, Hsu CC, Kao CL. Genetics behind Cerebral Disease with Ocular Comorbidity: Finding Parallels between the Brain and Eye Molecular Pathology. Int J Mol Sci 2022; 23:ijms23179707. [PMID: 36077104 PMCID: PMC9456058 DOI: 10.3390/ijms23179707] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Revised: 08/18/2022] [Accepted: 08/22/2022] [Indexed: 11/30/2022] Open
Abstract
Cerebral visual impairments (CVIs) is an umbrella term that categorizes miscellaneous visual defects with parallel genetic brain disorders. While the manifestations of CVIs are diverse and ambiguous, molecular diagnostics stand out as a powerful approach for understanding pathomechanisms in CVIs. Nevertheless, the characterization of CVI disease cohorts has been fragmented and lacks integration. By revisiting the genome-wide and phenome-wide association studies (GWAS and PheWAS), we clustered a handful of renowned CVIs into five ontology groups, namely ciliopathies (Joubert syndrome, Bardet–Biedl syndrome, Alstrom syndrome), demyelination diseases (multiple sclerosis, Alexander disease, Pelizaeus–Merzbacher disease), transcriptional deregulation diseases (Mowat–Wilson disease, Pitt–Hopkins disease, Rett syndrome, Cockayne syndrome, X-linked alpha-thalassaemia mental retardation), compromised peroxisome disorders (Zellweger spectrum disorder, Refsum disease), and channelopathies (neuromyelitis optica spectrum disorder), and reviewed several mutation hotspots currently found to be associated with the CVIs. Moreover, we discussed the common manifestations in the brain and the eye, and collated animal study findings to discuss plausible gene editing strategies for future CVI correction.
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Affiliation(s)
- Kao-Jung Chang
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
| | - Hsin-Yu Wu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | | | - Cheng-Yi Li
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yu-Jer Hsiao
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yi-Chun Chi
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Tzu-Chen Lo
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - He-Jhen Dai
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Medical Research, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Yi-Chiang Yang
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Ding-Hao Liu
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - De-Kuang Hwang
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
| | - Shih-Jen Chen
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei 11217, Taiwan
| | - Chih-Chien Hsu
- School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Ophthalmology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung 80708, Taiwan
- Correspondence: (C.-C.H.); (C.-L.K.); Tel.: +886-2-287-573-25 (C.-C.H.); +886-2-287-573-63 (C.-L.K.)
| | - Chung-Lan Kao
- Institute of Clinical Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Department of Physical Medicine and Rehabilitation, Taipei Veterans General Hospital, Taipei 11217, Taiwan
- Department of Physical Medicine and Rehabilitation, School of Medicine, National Yang Ming Chiao Tung University, Taipei 112304, Taiwan
- Center for Intelligent Drug Systems and Smart Bio-Devices (IDS2B), National Yang Ming Chiao Tung University, Hsinchu 300093, Taiwan
- Correspondence: (C.-C.H.); (C.-L.K.); Tel.: +886-2-287-573-25 (C.-C.H.); +886-2-287-573-63 (C.-L.K.)
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Rashmi R, Majumdar S. Pan-Cancer Analysis Reveals the Prognostic Potential of the THAP9/THAP9-AS1 Sense-Antisense Gene Pair in Human Cancers. Noncoding RNA 2022; 8:ncrna8040051. [PMID: 35893234 PMCID: PMC9326536 DOI: 10.3390/ncrna8040051] [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: 04/05/2022] [Revised: 06/11/2022] [Accepted: 06/13/2022] [Indexed: 11/18/2022] Open
Abstract
Human THAP9, which encodes a domesticated transposase of unknown function, and lncRNA THAP9-AS1 (THAP9-antisense1) are arranged head-to-head on opposite DNA strands, forming a sense and antisense gene pair. We predict that there is a bidirectional promoter that potentially regulates the expression of THAP9 and THAP9-AS1. Although both THAP9 and THAP9-AS1 are reported to be involved in various cancers, their correlative roles on each other’s expression has not been explored. We analyzed the expression levels, prognosis, and predicted biological functions of the two genes across different cancer datasets (TCGA, GTEx). We observed that although the expression levels of the two genes, THAP9 and THAP9-AS1, varied in different tumors, the expression of the gene pair was strongly correlated with patient prognosis; higher expression of the gene pair was usually linked to poor overall and disease-free survival. Thus, THAP9 and THAP9-AS1 may serve as potential clinical biomarkers of tumor prognosis. Further, we performed a gene co-expression analysis (using WGCNA) followed by a differential gene correlation analysis (DGCA) across 22 cancers to identify genes that share the expression pattern of THAP9 and THAP9-AS1. Interestingly, in both normal and cancer samples, THAP9 and THAP9-AS1 often co-express; moreover, their expression is positively correlated in each cancer type, suggesting the coordinated regulation of this H2H gene pair.
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9
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Expression, Purification, Characterization and Cellular Uptake of MeCP2 Variants. Protein J 2022; 41:345-359. [PMID: 35546650 PMCID: PMC9122891 DOI: 10.1007/s10930-022-10054-9] [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] [Accepted: 04/20/2022] [Indexed: 11/05/2022]
Abstract
The transcriptional regulator Methyl-CpG-binding protein 2 (MeCP2) is an intrinsically disordered protein, mutations in which, are implicated in the onset of Rett Syndrome, a severe and debilitating neurodevelopmental disorder. Delivery of this protein fused to the cell-penetrating peptide TAT could allow for the intracellular replenishment of functional MeCP2 and hence potentially serve as a prospective Rett Syndrome therapy. This work outlines the expression, purification and characterization of various TAT-MeCP2 constructs as well as their full-length and shortened eGFP fusion variants. The latter two constructs were used for intracellular uptake studies with subsequent analysis via western blotting and live-cell imaging. All purified MeCP2 samples exhibited high degree of stability and very little aggregation propensity. Full length and minimal TAT-MeCP2-eGFP were found to efficiently transduce into human dermal and murine fibroblasts and localize to cell nuclei. These findings clearly support the utility of MeCP2-based protein replacement therapy as a potential Rett Syndrome treatment option.
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10
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Ayaz G, Turan G, Olgun ÇE, Kars G, Karakaya B, Yavuz K, Demiralay ÖD, Can T, Muyan M, Yaşar P. A prelude to the proximity interaction mapping of CXXC5. Sci Rep 2021; 11:17587. [PMID: 34475492 PMCID: PMC8413330 DOI: 10.1038/s41598-021-97060-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 08/17/2021] [Indexed: 11/09/2022] Open
Abstract
CXXC5 is a member of the zinc-finger CXXC family proteins that interact with unmodified CpG dinucleotides through a conserved ZF-CXXC domain. CXXC5 is involved in the modulation of gene expressions that lead to alterations in diverse cellular events. However, the underlying mechanism of CXXC5-modulated gene expressions remains unclear. Proteins perform their functions in a network of proteins whose identities and amounts change spatiotemporally in response to various stimuli in a lineage-specific manner. Since CXXC5 lacks an intrinsic transcription regulatory function or enzymatic activity but is a DNA binder, CXXC5 by interacting with proteins could act as a scaffold to establish a chromatin state restrictive or permissive for transcription. To initially address this, we utilized the proximity-dependent biotinylation approach. Proximity interaction partners of CXXC5 include DNA and chromatin modifiers, transcription factors/co-regulators, and RNA processors. Of these, CXXC5 through its CXXC domain interacted with EMD, MAZ, and MeCP2. Furthermore, an interplay between CXXC5 and MeCP2 was critical for a subset of CXXC5 target gene expressions. It appears that CXXC5 may act as a nucleation factor in modulating gene expressions. Providing a prelude for CXXC5 actions, our results could also contribute to a better understanding of CXXC5-mediated cellular processes in physiology and pathophysiology.
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Affiliation(s)
- Gamze Ayaz
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey. .,Cancer and Stem Cell Epigenetics Section, Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Gizem Turan
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Çağla Ece Olgun
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Gizem Kars
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Burcu Karakaya
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Kerim Yavuz
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Öykü Deniz Demiralay
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey
| | - Tolga Can
- Department of Computer Engineering Middle, East Technical University, 06800, Ankara, Turkey
| | - Mesut Muyan
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey. .,Cansyl Laboratories, Middle East Technical University, 06800, Ankara, Turkey.
| | - Pelin Yaşar
- Department of Biological Sciences, Middle East Technical University, 06800, Ankara, Turkey.,Epigenetics and Stem Cell Biology Laboratory, Single Cell Dynamics Group, National Institute of Environmental Health Sciences, Research Triangle Park, NC, 27709, USA
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11
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D'Mello SR. MECP2 and the Biology of MECP2 Duplication Syndrome. J Neurochem 2021; 159:29-60. [PMID: 33638179 DOI: 10.1111/jnc.15331] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Revised: 01/21/2021] [Accepted: 02/18/2021] [Indexed: 11/27/2022]
Abstract
MECP2 duplication syndrome (MDS), a rare X-linked genomic disorder affecting predominantly males, is caused by duplication of the chromosomal region containing the methyl CpG binding protein-2 (MECP2) gene, which encodes methyl-CpG-binding protein 2 (MECP2), a multi-functional protein required for proper brain development and maintenance of brain function during adulthood. Disease symptoms include severe motor and cognitive impairment, delayed or absent speech development, autistic features, seizures, ataxia, recurrent respiratory infections and shortened lifespan. The cellular and molecular mechanisms by which a relatively modest increase in MECP2 protein causes such severe disease symptoms are poorly understood and consequently there are no treatments available for this fatal disorder. This review summarizes what is known to date about the structure and complex regulation of MECP2 and its many functions in the developing and adult brain. Additionally, recent experimental findings on the cellular and molecular underpinnings of MDS based on cell culture and mouse models of the disorder are reviewed. The emerging picture from these studies is that MDS is a neurodegenerative disorder in which neurons die in specific parts of the central nervous system, including the cortex, hippocampus, cerebellum and spinal cord. Neuronal death likely results from astrocytic dysfunction, including a breakdown of glutamate homeostatic mechanisms. The role of elevations in the expression of glial acidic fibrillary protein (GFAP) in astrocytes and the microtubule-associated protein, Tau, in neurons to the pathogenesis of MDS is discussed. Lastly, potential therapeutic strategies to potentially treat MDS are discussed.
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12
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Emerging physiological and pathological roles of MeCP2 in non-neurological systems. Arch Biochem Biophys 2021; 700:108768. [PMID: 33485848 DOI: 10.1016/j.abb.2021.108768] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2020] [Revised: 01/08/2021] [Accepted: 01/14/2021] [Indexed: 02/08/2023]
Abstract
Numerous neurological and non-neurological disorders are associated with dysfunction of epigenetic modulators, and methyl CpG binding protein 2 (MeCP2) is one of such proteins. Initially identified as a transcriptional repressor, MeCP2 specifically binds to methylated DNA, and mutations of MeCP2 have been shown to cause Rett syndrome (RTT), a severe neurological disorder. Recently, accumulating evidence suggests that ubiquitously expressed MeCP2 also plays a central role in non-neurological disorders including cardiac dysfunction, liver injury, respiratory disorders, urological dysfunction, adipose tissue metabolism disorders, movement abnormality and inflammatory responses in a DNA methylation dependent or independent manner. Despite significant progresses in our understanding of MeCP2 over the last few decades, there is still a considerable knowledge gap to translate the in vitro and in vivo experimental findings into therapeutic interventions. In this review, we provide a synopsis of the role of MeCP2 in the pathophysiology of non-neurological disorders, MeCP2-based research directions and therapeutic strategies for non-neurological disorders are also discussed.
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13
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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: 56] [Impact Index Per Article: 18.7] [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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14
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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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15
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Jdila MB, Triki CC, Ghorbel R, Bouchalla W, Ncir SB, Kamoun F, Fakhfakh F. Unusual double mutation in MECP2 and CDKL5 genes in Rett-like syndrome: Correlation with phenotype and genes expression. Clin Chim Acta 2020; 508:287-294. [PMID: 32445745 DOI: 10.1016/j.cca.2020.05.037] [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: 04/12/2020] [Revised: 05/12/2020] [Accepted: 05/19/2020] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Rett syndrome (RTT) is a neuro-developmental disorder affecting almost exclusively females and it divided into classical and atypical forms of the disease. RTT-like syndrome was also described and presents an overlapping phenotype of RTT. RTT-like syndrome has been associated with several genes including MECP2 and CDKL5 having common biological pathways and regulatory interactions especially during neural maturation and synaptogenesis. METHODS We report patient with Rett-like syndrome for whom clinical features and their progression guided toward the screening of two candidate genes MECP2 and CDKL5 by sequencing. Severity score was evaluated by "Rett Assessment Rating Scale" (R.A.R.S.). Predictions of pahogenicity and functional effects used several bioinformatic tools and qRT-PCR was conducted to evaluate gene expression. RESULTS Mutational screening revealed two mutations c.1065 C > A (p.S355R) in MECP2 gene and c.616 G > A (p.D206N) mutation in CDKL5 gene in the patient with a high R.A.R.S. Bioinformatic investigations predicted a moderate effect of p.S355R in MECP2 gene but a more pathogenic one of p.D206N mutation in CDKL5. Effect of c.616 G > A mutation on structure and stability of CDKL5 mRNA was confirmed by qRT-PCR. Additionally, analysis of gene expression revealed a drastic effect of CDKL5 mutant on its MeCP2 and Dnmt1 substrates and also on its MYCN regulator. CONCLUSIONS The co-existence of the two mutations in CDKL5 and MECP2 genes could explain the severe phenotype in our patient with RTT-Like and is consistent with the data related to the interactions of CDKL5 with MeCP2 and Dnmt1 proteins.
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Affiliation(s)
- Marwa Ben Jdila
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Tunisia; Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, Sfax University, Tunisia.
| | - Chahnez Charfi Triki
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Tunisia; Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Tunisia
| | - Rania Ghorbel
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, Sfax University, Tunisia
| | - Wafa Bouchalla
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Tunisia; Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Tunisia
| | - Sihem Ben Ncir
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Tunisia; Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Tunisia
| | - Fatma Kamoun
- Research Laboratory 'NeuroPédiatrie' (LR19ES15), Sfax Medical School, Sfax University, Tunisia; Child Neurology Department, Hedi Chaker Universitary Hospital of Sfax, Tunisia
| | - Faiza Fakhfakh
- Laboratory of Molecular and Functional Genetics, Faculty of Science of Sfax, Sfax University, Tunisia.
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16
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Qiu R, Zhang J, Xiang X. The splicing-factor Prp40 affects dynein-dynactin function in Aspergillus nidulans. Mol Biol Cell 2020; 31:1289-1301. [PMID: 32267207 PMCID: PMC7353152 DOI: 10.1091/mbc.e20-03-0166] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The multi-component cytoplasmic dynein transports cellular cargoes with the help of another multi-component complex dynactin, but we do not know enough about factors that may affect the assembly and functions of these proteins. From a genetic screen for mutations affecting early-endosome distribution in Aspergillus nidulans, we identified the prp40AL438* mutation in Prp40A, a homologue of Prp40, an essential RNA-splicing factor in the budding yeast. Prp40A is not essential for splicing, although it associates with the nuclear splicing machinery. The prp40AL438* mutant is much healthier than the ∆prp40A mutant, but both mutants exhibit similar defects in dynein-mediated early-endosome transport and nuclear distribution. In the prp40AL438* mutant, the frequency but not the speed of dynein-mediated early-endosome transport is decreased, which correlates with a decrease in the microtubule plus-end accumulations of dynein and dynactin. Within the dynactin complex, the actin-related protein Arp1 forms a mini-filament. In a pull-down assay, the amount of Arp1 pulled down with its pointed-end protein Arp11 is lowered in the prp40AL438* mutant. In addition, we found from published interactome data that a mammalian Prp40 homologue PRPF40A interacts with Arp1. Thus, Prp40 homologues may regulate the assembly or function of dynein–dynactin and their mechanisms deserve to be further studied.
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Affiliation(s)
- Rongde Qiu
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Jun Zhang
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
| | - Xin Xiang
- Department of Biochemistry and Molecular Biology, F. Edward Hébert School of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814
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17
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MeCP2 and Chromatin Compartmentalization. Cells 2020; 9:cells9040878. [PMID: 32260176 PMCID: PMC7226738 DOI: 10.3390/cells9040878] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 03/27/2020] [Accepted: 04/01/2020] [Indexed: 12/24/2022] Open
Abstract
Methyl-CpG binding protein 2 (MeCP2) is a multifunctional epigenetic reader playing a role in transcriptional regulation and chromatin structure, which was linked to Rett syndrome in humans. Here, we focus on its isoforms and functional domains, interactions, modifications and mutations found in Rett patients. Finally, we address how these properties regulate and mediate the ability of MeCP2 to orchestrate chromatin compartmentalization and higher order genome architecture.
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18
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Tillotson R, Bird A. The Molecular Basis of MeCP2 Function in the Brain. J Mol Biol 2020; 432:1602-1623. [PMID: 31629770 DOI: 10.1016/j.jmb.2019.10.004] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Revised: 10/04/2019] [Accepted: 10/05/2019] [Indexed: 12/14/2022]
Abstract
MeCP2 is a reader of the DNA methylome that occupies a large proportion of the genome due to its high abundance and the frequency of its target sites. It has been the subject of extensive study because of its link with 'MECP2-related disorders', of which Rett syndrome is the most prevalent. This review integrates evidence from patient mutation data with results of experimental studies using mouse models, cell lines and in vitro systems to critically evaluate our understanding of MeCP2 protein function. Recent evidence challenges the idea that MeCP2 is a multifunctional hub that integrates diverse processes to underpin neuronal function, suggesting instead that its primary role is to recruit the NCoR1/2 co-repressor complex to methylated sites in the genome, leading to dampening of gene expression.
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Affiliation(s)
- Rebekah Tillotson
- Genetics and Genome Biology Program, The Hospital for Sick Children, The Peter Gilgan Centre for Research and Learning, Toronto, ON M5G 0A4, Canada; Medical Research Council (MRC) Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, John Radcliffe Hospital, Headington, Oxford, OX3 9DS, UK
| | - Adrian Bird
- Wellcome Centre for Cell Biology, University of Edinburgh, The Michael Swann Building, King's Buildings, Max Born Crescent, Edinburgh, EH9 3BF, UK.
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19
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Hettiarachchi D, Neththikumara NF, Pathirana BAPS, Dissanayake VHW. Variant Profile of MECP2 Gene in Sri Lankan Patients with Rett Syndrome. J Autism Dev Disord 2019; 50:118-126. [DOI: 10.1007/s10803-019-04230-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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20
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Huo Z, Zhai S, Weng Y, Qian H, Tang X, Shi Y, Deng X, Wang Y, Shen B. PRPF40A as a potential diagnostic and prognostic marker is upregulated in pancreatic cancer tissues and cell lines: an integrated bioinformatics data analysis. Onco Targets Ther 2019; 12:5037-5051. [PMID: 31303762 PMCID: PMC6610298 DOI: 10.2147/ott.s206039] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2019] [Accepted: 05/31/2019] [Indexed: 12/15/2022] Open
Abstract
Background Pre-mRNA processing factor 40 homolog A (PRPF40A) is an important protein involved in pre-mRNA splicing and is expressed in a variety of cell types. However, the function of PRPF40A in pancreatic cancer remains unclear. Therefore, our study is to investigate the role of PRPF40A in the pathogenesis of pancreatic cancer. Materials and methods We extracted expression data and clinical information of PRPF40A from different online databases, including the Cancer Genome Atlas (TCGA), Oncomine and the Gene Expression Omnibus (GEO). Subsequently, samples were collected from patients to validate gene expression using qPCR, Western blotting and immunohistochemical (IHC) analyses. Receiver operating characteristic (ROC) and Kaplan-Meier curve were used to evaluate the diagnostic and prognostic potential. Colony formation assays and CCK-8 assays were performed to measure the proliferative capacity of pancreatic cancer. Finally, gene ontology (GO) and pathway enrichment analyses of co-expressed genes of PRPF40A were conducted using the Database for Annotation, Visualization and Integrated Discovery (DAVID). Results We found that PRPF40A was upregulated based on data from both the online databases and our samples. PRPF40A possessed a significant diagnostic value, and its overexpression was associated with poor prognosis. PRPF40A knockdown inhibited cell proliferation in pancreatic cancer. GO and pathway analysis showed that the co-expressed genes were mainly involved in viral processing, mRNA splicing and the AMPK signaling pathway. Conclusion The results suggest that PRPF40A is an oncogene and can serve as a diagnostic and prognostic biomarker for pancreatic cancer. However, the underlying mechanisms remain to be elucidated.
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Affiliation(s)
- Zhen Huo
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Shuyu Zhai
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Yuanchi Weng
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Hao Qian
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Xiaomei Tang
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Yusheng Shi
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Xiaxing Deng
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Yue Wang
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
| | - Baiyong Shen
- Department of General Surgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, People's Republic of China
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Abstract
Elucidating the functions of a particular gene is paramount to the understanding of how its dysfunction contributes to disease. This is especially important when the gene is implicated in multiple different disorders. One such gene is methyl-CpG-binding protein 2 (MECP2), which has been most prominently associated with the neurodevelopmental disorder Rett syndrome, as well as major neuropsychiatric disorders such as autism and schizophrenia. Being initially identified as a transcriptional regulator that modulates gene expression and subsequently also shown to be involved in other molecular events, dysfunction of the MeCP2 protein has the potential to affect many cellular processes. In this chapter, we will briefly review the functions of the MeCP2 protein and how its mutations are implicated in Rett syndrome and other neuropsychiatric disorders. We will further discuss about the mouse models that have been generated to specifically dissect the function of MeCP2 in different cell types and brain regions. It is envisioned that such thorough and targeted examination of MeCP2 functions can aid in enlightening the role that it plays in normal and dysfunctional physiological systems.
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Affiliation(s)
- Eunice W M Chin
- Neuroscience and Mental Health Faculty, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | - Eyleen L K Goh
- Neuroscience and Mental Health Faculty, Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore.
- Department of Research, National Neuroscience Institute, Singapore, Singapore.
- Neuroscience Academic Clinical Programme, Singhealth Duke-NUS Academic Medical Center, Singapore, Singapore.
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22
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Díaz Casas A, Casanova Sepúlveda G, Sánchez Negrón O, Caro Muñiz AP, Malavé Ramos SR, Cebollero López AR, Pastrana-Ríos B. Molecular biophysical characterization of the third FF domain of Homo sapiens Prp40 homolog A. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.04.059] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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23
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Abstract
Pre-mRNA processing protein 40 (Prp40) is a nuclear protein that has a role in pre-mRNA splicing. Prp40 possesses two leucine-rich nuclear export signals, but little is known about the function of Prp40 in the export process. Another protein that has a role in protein export is centrin, a member of the EF-hand superfamily of Ca2+-binding proteins. Prp40 was found to be a centrin target by yeast-two-hybrid screening using both Homo sapiens centrin 2 (Hscen2) and Chlamydomonas reinhardtii centrin (Crcen). We identified a centrin-binding site within H. sapiens Prp40 homolog A (HsPrp40A), which contains a hydrophobic triad W1L4L8 that is known to be important in the interaction with centrin. This centrin-binding site is highly conserved within the first nuclear export signal consensus sequence identified in Saccharomyces cerevisiae Prp40. Here, we examine the interaction of HsPrp40A peptide (HsPrp40Ap) with both Hscen2 and Crcen by isothermal titration calorimetry. We employed the thermodynamic parameterization to estimate the polar and apolar surface area of the interface. In addition, we have defined the molecular mechanism of thermally induced unfolding and dissociation of the Crcen-HsPrp40Ap complex using two-dimensional infrared correlation spectroscopy. These complementary techniques showed for the first time, to our knowledge, that HsPrp40Ap interacts with centrin in vitro, supporting a coupled functional role for these proteins in pre-mRNA splicing.
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Yorkie Regulates Neurodegeneration Through Canonical Pathway and Innate Immune Response. Mol Neurobiol 2017; 55:1193-1207. [PMID: 28102471 DOI: 10.1007/s12035-017-0388-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 01/04/2017] [Indexed: 12/12/2022]
Abstract
Expansion of CAG repeats in certain genes has long been known to be associated with neurodegenerastion, but the quest to identity the underlying mechanisms is still on. Here, we analyzed the role of Yorkie, the coactivator of the Hippo pathway, and provide evidence to state that it is a robust genetic modifier of polyglutamine (PolyQ)-mediated neurodegeneration. Yorkie reduces the pathogenicity of inclusion bodies in the cell by activating cyclin E and bantam, rather than by preventing apoptosis through DIAP1. PolyQ aggregates inhibit Yorkie functioning at the protein, rather than the transcript level, and this is probably accomplished by the interaction between PolyQ and Yorkie. We show that PolyQ aggregates upregulate expression of antimicrobial peptides (AMPs) and Yorkie negatively regulates immune deficiency (IMD) and Toll pathways through relish and cactus, respectively, thus reducing AMPs and mitigating PolyQ affects. These studies strongly suggest a novel mechanism of suppression of PolyQ-mediated neurotoxicity by Yorkie through multiple channels.
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MeCP2, A Modulator of Neuronal Chromatin Organization Involved in Rett Syndrome. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2017; 978:3-21. [PMID: 28523538 DOI: 10.1007/978-3-319-53889-1_1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
From an epigenetic perspective, the genomic chromatin organization of neurons exhibits unique features when compared to somatic cells. Methyl CpG binding protein 2 (MeCP2), through its ability to bind to methylated DNA, seems to be a major player in regulating such unusual organization. An important contribution to this uniqueness stems from the intrinsically disordered nature of this highly abundant chromosomal protein in neurons. Upon its binding to methylated/hydroxymethylated DNA, MeCP2 is able to recruit a plethora of interacting protein and RNA partners. The final outcome is a highly specialized chromatin organization wherein linker histones (histones of the H1 family) and MeCP2 share an organizational role that dynamically changes during neuronal development and that it is still poorly understood. MeCP2 mutations alter its chromatin-binding dynamics and/or impair the ability of the protein to interact with some of its partners, resulting in Rett syndrome (RTT). Therefore, deciphering the molecular details involved in the MeCP2 neuronal chromatin arrangement is critical for our understanding of the proper and altered functionality of these cells.
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From Function to Phenotype: Impaired DNA Binding and Clustering Correlates with Clinical Severity in Males with Missense Mutations in MECP2. Sci Rep 2016; 6:38590. [PMID: 27929079 PMCID: PMC5144150 DOI: 10.1038/srep38590] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Accepted: 11/11/2016] [Indexed: 11/25/2022] Open
Abstract
Mutations in the MECP2 gene cause Rett syndrome (RTT). MeCP2 binds to chromocentric DNA through its methyl CpG-binding domain (MBD) to regulate gene expression. In heterozygous females the variable phenotypic severity is modulated by non-random X-inactivation, thus making genotype-phenotype comparisons unreliable. However, genotype-phenotype correlations in males with hemizygousMECP2 mutations can provide more accurate insights in to the true biological effect of specific mutations. Here, we compared chromatin organization and binding dynamics for twelve MeCP2 missense mutations (including two novel and the five most common MBD missense RTT mutations) and identifiedacorrelation with phenotype in hemizygous males. We observed impaired interaction of MeCP2-DNA for mutations around the MBD-DNA binding interface, and defective chromatin clustering for distal MBD mutations. Furthermore, binding and mobility dynamics show a gradient of impairment depending on the amino acid properties and tertiary structure within the MBD. Interestingly, a wide range of phenotypic/clinical severity, ranging from neonatal encephalopathy to mild psychiatric abnormalities were observed and all are consistent with our functional/molecular results. Overall, clinical severity showed a direct correlation with the functional impairment of MeCP2. These mechanistic and phenotypic correlations of MeCP2 mutations will enable improved and individualized diagnostics, and may lead to personalized therapeutic interventions.
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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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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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Poh WJ, Wee CPP, Gao Z. DNA Methyltransferase Activity Assays: Advances and Challenges. Am J Cancer Res 2016; 6:369-91. [PMID: 26909112 PMCID: PMC4737724 DOI: 10.7150/thno.13438] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 10/12/2015] [Indexed: 12/28/2022] Open
Abstract
DNA methyltransferases (MTases), a family of enzymes that catalyse the methylation of DNA, have a profound effect on gene regulation. A large body of evidence has indicated that DNA MTase is potentially a predictive biomarker closely associated with genetic disorders and genetic diseases like cancer. Given the attention bestowed onto DNA MTases in molecular biology and medicine, highly sensitive detection of DNA MTase activity is essential in determining gene regulation, epigenetic modification, clinical diagnosis and therapeutics. Conventional techniques such as isotope labelling are effective, but they often require laborious sample preparation, isotope labelling, sophisticated equipment and large amounts of DNA, rendering them unsuitable for uses at point-of-care. Simple, portable, highly sensitive and low-cost assays are urgently needed for DNA MTase activity screening. In most recent technological advances, many alternative DNA MTase activity assays such as fluorescent, electrochemical, colorimetric and chemiluminescent assays have been proposed. In addition, many of them are coupled with nanomaterials and/or enzymes to significantly enhance their sensitivity. Herein we review the progress in the development of DNA MTase activity assays with an emphasis on assay mechanism and performance with some discussion on challenges and perspectives. It is hoped that this article will provide a broad coverage of DNA MTase activity assays and their latest developments and open new perspectives toward the development of DNA MTase activity assays with much improved performance for uses in molecular biology and clinical practice.
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Becerra S, Andrés-León E, Prieto-Sánchez S, Hernández-Munain C, Suñé C. Prp40 and early events in splice site definition. WILEY INTERDISCIPLINARY REVIEWS-RNA 2015; 7:17-32. [PMID: 26494226 DOI: 10.1002/wrna.1312] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 09/18/2015] [Accepted: 09/22/2015] [Indexed: 12/14/2022]
Abstract
The alternative splicing (AS) of precursor messenger RNA (pre-mRNA) is a tightly regulated process through which introns are removed to leave the resulting exons in the mRNA appropriately aligned and ligated. The AS of pre-mRNA is a key mechanism for increasing the complexity of proteins encoded in the genome. In humans, more than 90% of genes undergo AS, underscoring the importance of this process in RNA biogenesis. As such, AS misregulation underlies multiple human diseases. The splicing reaction is catalyzed by the spliceosome, a highly dynamic complex that assembles at or near the intron/exon boundaries and undergoes sequential conformational and compositional changes during splicing. The initial recognition of splice sites defines the exons that are going to be removed, which is a critical step in the highly regulated splicing process. Although the available lines of evidence are increasing, the molecular mechanisms governing AS, including the initial interactions occurring at intron/exon boundaries, and the factors that modulate these critical connections by functioning as a scaffold for active-site RNAs or proteins, remain poorly understood. In this review, we summarize the major hallmarks of the initial steps in the splicing process and the role of auxiliary factors that contribute to the assembly of the spliceosomal complex. We also discuss the role of the essential yeast Prp40 protein and its mammalian homologs in the specificity of this pre-mRNA processing event. In addition, we provide the first exhaustive phylogenetic analysis of the molecular evolution of Prp40 family members. WIREs RNA 2016, 7:17-32. doi: 10.1002/wrna.1312 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Soraya Becerra
- Department of Molecular Biology, Instituto de Parasitología y Biomedicina "López Neyra", Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada 18016, Spain
| | - Eduardo Andrés-León
- Bioinformatics Unit, Instituto de Parasitología y Biomedicina "López Neyra", Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada 18016, Spain
| | - Silvia Prieto-Sánchez
- Department of Molecular Biology, Instituto de Parasitología y Biomedicina "López Neyra", Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada 18016, Spain
| | - Cristina Hernández-Munain
- Department of Cell Biology and Immunology, Instituto de Parasitología y Biomedicina "López Neyra", Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada 18016, Spain
| | - Carlos Suñé
- Department of Molecular Biology, Instituto de Parasitología y Biomedicina "López Neyra", Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada 18016, Spain
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MECP2, a gene associated with Rett syndrome in humans, shows conserved coding regions, independent Alu insertions, and a novel transcript across primate evolution. BMC Genet 2015; 16:77. [PMID: 26148505 PMCID: PMC4493987 DOI: 10.1186/s12863-015-0240-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2014] [Accepted: 06/25/2015] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND The methyl-CpG Binding Protein two gene (MECP2) encodes a multifunctional protein comprising two isoforms involved in nuclear organization and regulation of splicing and mRNA template activity. This gene is normally expressed in all tissues, with a higher expression level in the brain during neuronal maturation. Loss of MECP2 function is the primary cause of Rett syndrome (RTT) in humans, a dominant, X-linked disorder dramatically affecting neural and motor development. RESULTS We investigated the molecular evolution of MECP2 in several primate taxa including 36 species in 16 genera of neotropical (platyrrhine) primates. The coding region of the MECP2_e2 isoform showed a high level of evolutionary conservation among humans and other primates, with amino acid substitutions in 14 codons and one in-frame insertion of a single serine codon, between codons 357 and 358, in Ateles paniscus. Most substitutions occurred in noncritical regions of MECP2 and the majority of the algorithms used for analyzing selection did not provide evidence of positive selection. Conversely, we found 48 sites under negative selection in different regions, 23 of which were consistently found by three different algorithms. Similar to an inverted Alu insert found previously in a lesser ape at a parallel location, one Alu insertion of approximately 300 bp in Cebus and Sapajus was found in intron 3. Phylogenetic reconstruction of the intron 3 data provided a topology that was coincident with the consensus arrangement of the primate taxa. RNAseq data in the neotropical primate Callimico goeldii revealed a novel transcript consisting of a noncontinuous region of the human-homologous intron 2 in this species; this transcript accounted for two putative polypeptides. CONCLUSIONS Despite the remarkable evolutionary conservation of MECP2, one in-frame codon insertion was observed in A. paniscus, and one region of intron 3 was affected by a trans-specific Alu retrotransposition in two neotropical primate genera. Moreover, identification of novel MECP2 transcripts in Callimico suggests that part of a homologous human intronic region might be expressed, and that the potential open reading frame in this region might be a subject of interest in RTT patients who carry an apparently normal MECP2 sequence.
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Becerra S, Montes M, Hernández-Munain C, Suñé C. Prp40 pre-mRNA processing factor 40 homolog B (PRPF40B) associates with SF1 and U2AF65 and modulates alternative pre-mRNA splicing in vivo. RNA (NEW YORK, N.Y.) 2015; 21:438-57. [PMID: 25605964 PMCID: PMC4338339 DOI: 10.1261/rna.047258.114] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
The first stable complex formed during the assembly of spliceosomes onto pre-mRNA substrates in mammals includes U1 snRNP, which recognizes the 5' splice site, and the splicing factors SF1 and U2AF, which bind the branch point sequence, polypyrimidine tract, and 3' splice site. The 5' and 3' splice site complexes are thought to be joined together by protein-protein interactions mediated by factors that ensure the fidelity of the initial splice site recognition. In this study, we identified and characterized PRPF40B, a putative mammalian ortholog of the U1 snRNP-associated yeast splicing factor Prp40. PRPF40B is highly enriched in speckles with a behavior similar to splicing factors. We demonstrated that PRPF40B interacts directly with SF1 and associates with U2AF(65). Accordingly, PRPF40B colocalizes with these splicing factors in the cell nucleus. Splicing assays with reporter minigenes revealed that PRPF40B modulates alternative splice site selection. In the case of Fas regulation of alternative splicing, weak 5' and 3' splice sites and exonic sequences are required for PRPF40B function. Placing our data in a functional context, we also show that PRPF40B depletion increased Fas/CD95 receptor number and cell apoptosis, which suggests the ability of PRPF40B to alter the alternative splicing of key apoptotic genes to regulate cell survival.
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Affiliation(s)
| | | | - Cristina Hernández-Munain
- Department of Cell Biology and Immunology, Instituto de Parasitología y Biomedicina "López Neyra" (IPBLN-CSIC), PTS, Granada 18016, Spain
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Fabio RA, Colombo B, Russo S, Cogliati F, Masciadri M, Foglia S, Antonietti A, Tavian D. Recent insights into genotype-phenotype relationships in patients with Rett syndrome using a fine grain scale. RESEARCH IN DEVELOPMENTAL DISABILITIES 2014; 35:2976-2986. [PMID: 25124696 DOI: 10.1016/j.ridd.2014.07.031] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Revised: 07/09/2014] [Accepted: 07/14/2014] [Indexed: 06/03/2023]
Abstract
Mutations in MECP2 gene cause Rett syndrome (RTT), a neurodevelopmental disorder affecting around 1 in 10,000 female births. The clinical picture of RTT appears quite heterogeneous for each single feature. Mutations in MECP2 gene have been associated with the onset of RTT. The most known gene function consists of transcriptional repression of specific target genes, mainly by the binding of its methyl binding domain (MBD) to methylated CpG nucleotides and recruiting co-repressors and histone deacetylase binding to DNA by its transcription repressor domain (TRD). This study aimed at evaluating a cohort of 114 Rett syndrome (RTT) patients with a detailed scale measuring the different kinds of impairments produced by the syndrome. The sample included relatively large subsets of the most frequent mutations, so that genotype-phenotype correlations could be tested. Results revealed that frequent missense mutations showed a specific profile in different areas of impairment. The R306C mutation, considered as producing mild impairment, was associated to a moderate phenotype in which behavioural characteristics were mainly affected. A notable difference emerged by comparing mutations truncating the protein before and after the nuclear localization signal; such a difference concerned prevalently the motor-functional and autonomy skills of the patients, affecting the management of everyday activities.
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Affiliation(s)
- Rosa Angela Fabio
- Department of Cognitive Science, Education and Cultural Studies, University of Messina, via Concezione 8, 98122 Messina, Italy.
| | - Barbara Colombo
- Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milano, Italy
| | - Silvia Russo
- Cytogenetics and Molecular Genetics Laboratory, Istituto Auxologico Italiano, via Ariosto 13, 20145 Milano, Italy
| | - Francesca Cogliati
- Cytogenetics and Molecular Genetics Laboratory, Istituto Auxologico Italiano, via Ariosto 13, 20145 Milano, Italy
| | - Maura Masciadri
- Cytogenetics and Molecular Genetics Laboratory, Istituto Auxologico Italiano, via Ariosto 13, 20145 Milano, Italy
| | - Silvia Foglia
- Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milano, Italy
| | - Alessandro Antonietti
- Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milano, Italy
| | - Daniela Tavian
- Department of Psychology, Catholic University of the Sacred Heart, Largo Gemelli 1, 20123 Milano, Italy; Laboratory of Cellular Biochemistry and Molecular Biology-CRIBENS, Catholic University of the Sacred Heart, Piazza Buonarroti 30, 20145 Milano, Italy
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Wolber LE, Steves CJ, Tsai PC, Deloukas P, Spector TD, Bell JT, Williams FMK. Epigenome-wide DNA methylation in hearing ability: new mechanisms for an old problem. PLoS One 2014; 9:e105729. [PMID: 25184702 PMCID: PMC4153547 DOI: 10.1371/journal.pone.0105729] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 07/28/2014] [Indexed: 11/24/2022] Open
Abstract
Epigenetic regulation of gene expression has been shown to change over time and may be associated with environmental exposures in common complex traits. Age-related hearing impairment is a complex disorder, known to be heritable, with heritability estimates of 57–70%. Epigenetic regulation might explain the observed difference in age of onset and magnitude of hearing impairment with age. Epigenetic epidemiology studies using unrelated samples can be limited in their ability to detect small effects, and recent epigenetic findings in twins underscore the power of this well matched study design. We investigated the association between venous blood DNA methylation epigenome-wide and hearing ability. Pure-tone audiometry (PTA) and Illumina HumanMethylation array data were obtained from female twin volunteers enrolled in the TwinsUK register. Two study groups were explored: first, an epigenome-wide association scan (EWAS) was performed in a discovery sample (n = 115 subjects, age range: 47–83 years, Illumina 27 k array), then replication of the top ten associated probes from the discovery EWAS was attempted in a second unrelated sample (n = 203, age range: 41–86 years, Illumina 450 k array). Finally, a set of monozygotic (MZ) twin pairs (n = 21 pairs) within the discovery sample (Illumina 27 k array) was investigated in more detail in an MZ discordance analysis. Hearing ability was strongly associated with DNA methylation levels in the promoter regions of several genes, including TCF25 (cg01161216, p = 6.6×10−6), FGFR1 (cg15791248, p = 5.7×10−5) and POLE (cg18877514, p = 6.3×10−5). Replication of these results in a second sample confirmed the presence of differential methylation at TCF25 (p(replication) = 6×10−5) and POLE (p(replication) = 0.016). In the MZ discordance analysis, twins' intrapair difference in hearing ability correlated with DNA methylation differences at ACP6 (cg01377755, r = −0.75, p = 1.2×10−4) and MEF2D (cg08156349, r = −0.75, p = 1.4×10−4). Examination of gene expression in skin, suggests an influence of differential methylation on expression, which may account for the variation in hearing ability with age.
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MESH Headings
- Acid Phosphatase/blood
- Acid Phosphatase/genetics
- Aged
- Aged, 80 and over
- Aging/blood
- Aging/genetics
- Aging/pathology
- Audiometry, Pure-Tone
- Basic Helix-Loop-Helix Transcription Factors/blood
- Basic Helix-Loop-Helix Transcription Factors/genetics
- DNA Methylation
- DNA Polymerase II/blood
- DNA Polymerase II/genetics
- Epigenesis, Genetic
- Female
- Genome, Human
- Hearing Loss, Functional/blood
- Hearing Loss, Functional/genetics
- Hearing Loss, Functional/physiopathology
- Humans
- MEF2 Transcription Factors/blood
- MEF2 Transcription Factors/genetics
- Middle Aged
- Poly-ADP-Ribose Binding Proteins
- Promoter Regions, Genetic
- Quantitative Trait, Heritable
- Receptor, Fibroblast Growth Factor, Type 1/blood
- Receptor, Fibroblast Growth Factor, Type 1/genetics
- Repressor Proteins/blood
- Repressor Proteins/genetics
- Twins, Monozygotic/genetics
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Affiliation(s)
- Lisa E. Wolber
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Claire J. Steves
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Pei-Chien Tsai
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Panos Deloukas
- William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, United Kingdom
- King Abdulaziz University, Jeddah, Saudi Arabia
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, United Kingdom
| | - Tim D. Spector
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Jordana T. Bell
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
| | - Frances M. K. Williams
- Department of Twin Research and Genetic Epidemiology, King's College London, London, United Kingdom
- * E-mail:
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35
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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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Cheng TL, Wang Z, Liao Q, Zhu Y, Zhou WH, Xu W, Qiu Z. MeCP2 suppresses nuclear microRNA processing and dendritic growth by regulating the DGCR8/Drosha complex. Dev Cell 2014; 28:547-60. [PMID: 24636259 DOI: 10.1016/j.devcel.2014.01.032] [Citation(s) in RCA: 178] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 01/01/2014] [Accepted: 01/31/2014] [Indexed: 01/13/2023]
Abstract
Loss- and gain-of-function mutations of the X-linked gene MECP2 (methyl-CpG binding protein 2) lead to severe neurodevelopmental disorders in humans, such as Rett syndrome (RTT) and autism. MeCP2 is previously known as a transcriptional repressor by binding to methylated DNA and recruiting histone deacetylase complex (HDAC). Here, we report that MeCP2 regulates gene expression posttranscriptionally by suppressing nuclear microRNA processing. We found that MeCP2 binds directly to DiGeorge syndrome critical region 8 (DGCR8), a critical component of the nuclear microRNA-processing machinery, and interferes with the assembly of Drosha and DGCR8 complex. Protein targets of MeCP2-suppressed microRNAs include CREB, LIMK1, and Pumilio2, which play critical roles in neural development. Gain of function of MeCP2 strongly inhibits dendritic and spine growth, which depends on the interaction of MeCP2 and DGCR8. Thus, control of microRNA processing via direct interaction with DGCR8 represents a mechanism for MeCP2 regulation of gene expression and neural development.
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Affiliation(s)
- Tian-Lin Cheng
- Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhizhi Wang
- Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
| | - Qiuming Liao
- Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Ying Zhu
- Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China
| | - Wen-Hao Zhou
- Department of Neonatology, Children's Hospital, Fudan University, Shanghai 201102, China
| | - Wenqing Xu
- Department of Biological Structure, University of Washington, Seattle, WA 98195, USA
| | - Zilong Qiu
- Institute of Neuroscience, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
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37
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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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Yin H, Zhou Y, Xu Z, Wang M, Ai S. Ultrasensitive electrochemical immunoassay for DNA methyltransferase activity and inhibitor screening based on methyl binding domain protein of MeCP2 and enzymatic signal amplification. Biosens Bioelectron 2013; 49:39-45. [DOI: 10.1016/j.bios.2013.04.040] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/20/2013] [Accepted: 04/22/2013] [Indexed: 01/22/2023]
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Maxwell SS, Pelka GJ, Tam PP, El-Osta A. Chromatin context and ncRNA highlight targets of MeCP2 in brain. RNA Biol 2013; 10:1741-57. [PMID: 24270455 DOI: 10.4161/rna.26921] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
The discovery that Rett syndrome (RTT) is caused by mutation of the methyl-CpG-binding-protein MeCP2 provided a major breakthrough in understanding the neurodevelopmental disorder and accelerated MeCP2 research. However, gene regulation by MeCP2 is complicated. The current consensus for MeCP2 remains as a classical repressor complex, with major emphasis on its role in methylation-dependent binding and repression. However, recent evidence indicates additional regulatory roles, suggesting non-classical mechanisms in gene activation. This has opened the field of MeCP2 research and suggests that the gene targets may not be the usual suspects, that is, dependent only on DNA methylation. Here we examine how chromatin binding and sequence preference may confer MeCP2 functionality, and connect relevant pathways in an active genome. Finding both genomic and proteomic evidence to indicate MeCP2 spliceosome interaction, we consequently discovered broad MeCP2 enrichment of the transcriptome while our focus toward long non-coding RNA (lncRNA) revealed MeCP2 association with RNCR3. Our data may indicate an as-yet-unappreciated role between lncRNA and MeCP2. We hypothesize that ncRNA may mediate chromatin-remodeling events by interacting with MeCP2, thereby conferring changes in gene expression. We consider that these results may suggest new mechanisms of gene regulation conferred by MeCP2 and its interactions upon chromatin structure and gene function.
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Affiliation(s)
- Scott S Maxwell
- Epigenetics in Human Health and Disease Laboratory; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC, Australia
| | - Gregory J Pelka
- Embryology Unit; Children's Medical Research Institute; Sydney, NSW, Australia
| | - Patrick Pl Tam
- Embryology Unit; Children's Medical Research Institute; Sydney, NSW, Australia; Sydney Medical School; University of Sydney; Sydney, NSW, Australia
| | - Assam El-Osta
- Epigenetics in Human Health and Disease Laboratory; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC, Australia; Epigenomic Profiling Facility; Baker IDI Heart and Diabetes Institute; The Alfred Medical Research and Education Precinct; Melbourne, VIC, Australia; Department of Pathology; The University of Melbourne; Parkville, VIC, Australia; Faculty of Medicine, Nursing and Health Sciences; Monash University; VIC, Australia
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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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Yazicioglu MN, Monaldini L, Chu K, Khazi FR, Murphy SL, Huang H, Margaritis P, High KA. Cellular localization and characterization of cytosolic binding partners for Gla domain-containing proteins PRRG4 and PRRG2. J Biol Chem 2013; 288:25908-25914. [PMID: 23873930 PMCID: PMC3764795 DOI: 10.1074/jbc.m113.484683] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The genes encoding a family of proteins termed proline-rich γ-carboxyglutamic acid (PRRG) proteins were identified and characterized more than a decade ago, but their functions remain unknown. These novel membrane proteins have an extracellular γ-carboxyglutamic acid (Gla) protein domain and cytosolic WW binding motifs. We screened WW domain arrays for cytosolic binding partners for PRRG4 and identified novel protein-protein interactions for the protein. We also uncovered a new WW binding motif in PRRG4 that is essential for these newly found protein-protein interactions. Several of the PRRG-interacting proteins we identified are essential for a variety of physiologic processes. Our findings indicate possible novel and previously unidentified functions for PRRG proteins.
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Affiliation(s)
- Mustafa N Yazicioglu
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Luca Monaldini
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Kirk Chu
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Fayaz R Khazi
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Samuel L Murphy
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Heshu Huang
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104
| | - Paris Margaritis
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104,; the Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, and
| | - Katherine A High
- From the Division of Hematology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania 19104,; the Department of Pediatrics, Perelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania 19104, and; the Howard Hughes Medical Institute, Chevy Chase, Maryland 20815.
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Xu X, Pozzo-Miller L. A novel DNA-binding feature of MeCP2 contributes to Rett syndrome. Front Cell Neurosci 2013; 7:64. [PMID: 23675316 PMCID: PMC3648697 DOI: 10.3389/fncel.2013.00064] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2013] [Accepted: 04/18/2013] [Indexed: 11/16/2022] Open
Affiliation(s)
- Xin Xu
- Department of Neurobiology, The University of Alabama at Birmingham Birmingham, AL, USA
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Spectrum of MECP2 gene mutations in a cohort of Indian patients with Rett syndrome: Report of two novel mutations. Gene 2013; 515:78-83. [DOI: 10.1016/j.gene.2012.11.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Revised: 10/30/2012] [Accepted: 11/27/2012] [Indexed: 11/23/2022]
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Rauch A, Wieczorek D, Graf E, Wieland T, Endele S, Schwarzmayr T, Albrecht B, Bartholdi D, Beygo J, Di Donato N, Dufke A, Cremer K, Hempel M, Horn D, Hoyer J, Joset P, Röpke A, Moog U, Riess A, Thiel CT, Tzschach A, Wiesener A, Wohlleber E, Zweier C, Ekici AB, Zink AM, Rump A, Meisinger C, Grallert H, Sticht H, Schenck A, Engels H, Rappold G, Schröck E, Wieacker P, Riess O, Meitinger T, Reis A, Strom TM. Range of genetic mutations associated with severe non-syndromic sporadic intellectual disability: an exome sequencing study. Lancet 2012; 380:1674-82. [PMID: 23020937 DOI: 10.1016/s0140-6736(12)61480-9] [Citation(s) in RCA: 754] [Impact Index Per Article: 62.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
BACKGROUND The genetic cause of intellectual disability in most patients is unclear because of the absence of morphological clues, information about the position of such genes, and suitable screening methods. Our aim was to identify de-novo variants in individuals with sporadic non-syndromic intellectual disability. METHODS In this study, we enrolled children with intellectual disability and their parents from ten centres in Germany and Switzerland. We compared exome sequences between patients and their parents to identify de-novo variants. 20 children and their parents from the KORA Augsburg Diabetes Family Study were investigated as controls. FINDINGS We enrolled 51 participants from the German Mental Retardation Network. 45 (88%) participants in the case group and 14 (70%) in the control group had de-novo variants. We identified 87 de-novo variants in the case group, with an exomic mutation rate of 1·71 per individual per generation. In the control group we identified 24 de-novo variants, which is 1·2 events per individual per generation. More participants in the case group had loss-of-function variants than in the control group (20/51 vs 2/20; p=0·022), suggesting their contribution to disease development. 16 patients carried de-novo variants in known intellectual disability genes with three recurrently mutated genes (STXBP1, SYNGAP1, and SCN2A). We deemed at least six loss-of-function mutations in six novel genes to be disease causing. We also identified several missense alterations with potential pathogenicity. INTERPRETATION After exclusion of copy-number variants, de-novo point mutations and small indels are associated with severe, sporadic non-syndromic intellectual disability, accounting for 45-55% of patients with high locus heterogeneity. Autosomal recessive inheritance seems to contribute little in the outbred population investigated. The large number of de-novo variants in known intellectual disability genes is only partially attributable to known non-specific phenotypes. Several patients did not meet the expected syndromic manifestation, suggesting a strong bias in present clinical syndrome descriptions. FUNDING German Ministry of Education and Research, European Commission 7th Framework Program, and Swiss National Science Foundation.
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Affiliation(s)
- Anita Rauch
- Institute of Medical Genetics, University of Zurich, Schwerzenbach-Zurich, Switzerland
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Psoni S, Sofocleous C, Traeger-Synodinos J, Kitsiou-Tzeli S, Kanavakis E, Fryssira-Kanioura H. MECP2 mutations and clinical correlations in Greek children with Rett syndrome and associated neurodevelopmental disorders. Brain Dev 2012; 34:487-95. [PMID: 21982064 DOI: 10.1016/j.braindev.2011.09.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2011] [Revised: 09/05/2011] [Accepted: 09/06/2011] [Indexed: 10/17/2022]
Abstract
BACKGROUND Mutations in the MECP2 gene (methyl-CpG-binding protein-2) are responsible for 60-95% of cases of Rett syndrome (RTT), an X-linked dominant neurodevelopmental disorder affecting mostly girls. Classic RTT is characterized by normal early development followed by psychomotor regression and onset of microcephaly, although variant forms are also observed. MECP2 has also been implicated in variable mental retardation (MR) phenotypes, including X-linked Mental Retardation (XLMR), Fragile-X-like Syndrome (FXS) and Angelman-like (AS) phenotypes. AIM The aim of the study was: (a) to evaluate the incidence and spectrum of MECP2 mutations in children with RTT and variant MR; (b) to evaluate phenotype-genotype correlations. METHODS Exons 3-4 were analyzed for mutations in 281 MR patients (aged 13 months-27 years old, 144 males-137 females) consisting of 88 patients referred for RTT and 193 patients referred for AS-like and FXS-like types of MR. Statistical analysis included correlation between classic MECP2-positive and MECP2-negative and variant RTT patients, and frequency of MECP2 mutations in the various categories. RESULTS Mutations were detected in ≈ 70% of classic and ≈ 21% of variant RTT, respectively. Amongst MR cases, 2.1% carried MECP2 mutations. MECP2-positive females had more problems in ambulation, muscle tone, tremor and ataxia, respiratory disturbances, head growth, hand use and stereotypies. Classic RTT-positive versus negative had significant respiratory and sitting problems and versus variant RTT-positive females ambulatory, hand and stereotypies problems. CONCLUSION The analysis of the MECP2 gene could provide a diagnostic tool for RTT and non-specific MR research.
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Affiliation(s)
- Stavroula Psoni
- Department of Medical Genetics, University of Athens, Aghia Sophia Children's Hospital, Athens, Greece
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Montes M, Becerra S, Sánchez-Álvarez M, Suñé C. Functional coupling of transcription and splicing. Gene 2012; 501:104-17. [DOI: 10.1016/j.gene.2012.04.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Revised: 04/02/2012] [Accepted: 04/05/2012] [Indexed: 01/13/2023]
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Hite KC, Kalashnikova AA, Hansen JC. Coil-to-helix transitions in intrinsically disordered methyl CpG binding protein 2 and its isolated domains. Protein Sci 2012; 21:531-8. [PMID: 22294343 DOI: 10.1002/pro.2037] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2011] [Revised: 12/25/2011] [Accepted: 12/27/2011] [Indexed: 11/08/2022]
Abstract
Methyl CpG binding protein 2 (MeCP2) is a canonical intrinsically disordered protein (IDP), that is, it lacks stable secondary structure throughout its entire polypeptide chain. Because IDPs often have the propensity to become locally ordered, we tested whether full-length MeCP2 and its constituent domains would gain secondary structure in 2,2,2-trifluoroethanol (TFE), a cosolvent that stabilizes intramolecular hydrogen bonding in proteins. The α-helix, β-strand/turn, and unstructured content were determined as a function of TFE concentration by deconvolution of circular dichroism data. Results indicate that approximately two-thirds of the unstructured residues present in full-length MeCP2 were converted to α-helix in 70% TFE without a change in β-strand/turn. Thus, much of the MeCP2 polypeptide chain undergoes coil-to-helix transitions under conditions that favor intrachain hydrogen bond formation. The unstructured residues of the N-terminal (NTD) and C-terminal (CTD) domains were partially converted to α-helix in 70% TFE. In contrast, the central transcription regulation domain (TRD) became almost completely α-helical in 70% TFE. Unlike the NTD, CTD, and TRD, the unstructured content of the methyl DNA binding domain and the intervening domain did not change with increasing TFE concentration. These results indicate that the coil-to-helix transitions that occur in full-length MeCP2 are localized to the NTD, CTD, and TRD, with the TRD showing the greatest tendency for helix formation. The potential relationships between intrinsic disorder, coil-to-helix transitions, and MeCP2 structure and function are discussed.
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Affiliation(s)
- Kristopher C Hite
- Department of Biochemistry and Molecular Biology, Campus Delivery 1870, Colorado State University, Fort Collins, Colorado 80523, USA
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Vasiliou SA, Ali FR, Haddley K, Cardoso MC, Bubb VJ, Quinn JP. The SLC6A4 VNTR genotype determines transcription factor binding and epigenetic variation of this gene in response to cocaine in vitro. Addict Biol 2012; 17:156-70. [PMID: 21309950 DOI: 10.1111/j.1369-1600.2010.00288.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We demonstrated that the genotype of the variable number tandem repeats (VNTRs) in the linked polymorphic region (LPR) of the 5' promoter and in the intron 2 (Stin2) transcriptional regulatory domains of the serotonin transporter SLC6A4 gene determined its promoter interactions with transcription factors and co-activators in response to cocaine in the JAr cell line. The LPR variants contain 14 (short, s) or 16 (long, l) copies of a 22-23 bp repeat element, whereas the Stin2 VNTR exists as three variants containing 9, 10 or 12 copies of a 16-17 bp repeat. We observed a differential effect of cocaine on the association of the promoter with the transcription factor CTCF, which bound to both LPR alleles prior to cocaine exposure but only to the l-allele following exposure. Significantly, this differential effect of cocaine was correlated with the binding of the transcriptional regulator MeCP2 specifically to the s-allele and recruiting the histone deacetylase complex (HDAC). Concurrently, cocaine increased the association of positive histone marks over the SLC6A4 gene locus. At the Stin2 domain, we lost binding of the transcription factor YB-1, while CTCF remained bound. Our biochemical data are consistent with differential reporter gene activity directed by the individual or dual domains in response to cocaine in an Epstein-Barr virus-based episome model of stable transfections. These observations suggest that exposure of JAr cells to cocaine may result in differential binding of transcription factors and activators based on a specific genotype that might alter epigenetic parameters affecting gene expression after the initial challenge.
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A novel transcript of cyclin-dependent kinase-like 5 (CDKL5) has an alternative C-terminus and is the predominant transcript in brain. Hum Genet 2011; 131:187-200. [PMID: 21748340 DOI: 10.1007/s00439-011-1058-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 06/28/2011] [Indexed: 12/21/2022]
Abstract
The X-linked cyclin-dependent kinase-like 5 (CDKL5) gene is an important molecular determinant of early-onset intractable seizures with infantile spasms and Rett syndrome-like phenotype. The gene encodes a kinase that may influence components of molecular pathways associated with MeCP2. In humans there are two previously reported splice variants that differ in the 5' untranslated exons and produce the same 115 kDa protein. Furthermore, very recently, a novel transcript including a novel exon (16b) has been described. By aligning both the human and mouse CDKL5 proteins to the orthologs of other species, we identified a theoretical 107 kDa isoform with an alternative C-terminus that terminates in intron 18. In human brain and all other tissues investigated except the testis, this novel isoform is the major CDKL5 transcript. The detailed characterisation of this novel isoform of CDKL5 reveals functional and subcellular localisation attributes that overlap greatly, but not completely, with that of the previously studied human CDKL5 protein. Considering its predominant expression in the human and mouse brain, we believe that this novel isoform is likely to be of primary pathogenic importance in human diseases associated with CDKL5 deficiency, and suggest that screening of the related intronic sequence should be included in the molecular genetic analyses of patients with a suggestive clinical phenotype.
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50
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Adkins NL, Georgel PT. MeCP2: structure and functionThis paper is one of a selection of papers published in a Special Issue entitled 31st Annual International Asilomar Chromatin and Chromosomes Conference, and has undergone the Journal’s usual peer review process. Biochem Cell Biol 2011; 89:1-11. [DOI: 10.1139/o10-112] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Despite a vast body of literature linking chromatin structure to regulation of gene expression, the role of architectural proteins in higher order chromatin transitions required for transcription activation and repression has remained an under-studied field. To demonstrate the current knowledge of the role of such proteins, we have focused our attention on the methylated DNA binding and chromatin-associated protein MeCP2. Structural studies using chromatin assembled in vitro have revealed that MeCP2 can associate with nucleosomes in an N-terminus dependent manner and efficiently condense nucleosome arrays. The present review attempts to match MeCP2 structural domains, or lack thereof, and specific chromatin features needed for the proper recruitment of MeCP2 to its multiple functions as either activator or repressor. We specifically focused on MeCP2’s role in Rett syndrome, a neurological disorder associated with specific MeCP2 mutations.
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Affiliation(s)
- Nicholas L. Adkins
- Byrd Biotechnology Building, Department of Biological Sciences, Marshall University, 1 John Marshall Drive, Huntington, WV 25755, USA
| | - Philippe T. Georgel
- Byrd Biotechnology Building, Department of Biological Sciences, Marshall University, 1 John Marshall Drive, Huntington, WV 25755, USA
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