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Chizhikov VV, Iskusnykh IY. Cortical hem signaling center: functions, development, and potential implications for evolution and brain disorders. Neural Regen Res 2025; 20:1079-1080. [PMID: 38989940 DOI: 10.4103/nrr.nrr-d-23-01796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Accepted: 01/24/2024] [Indexed: 07/12/2024] Open
Affiliation(s)
- Victor V Chizhikov
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA
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2
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Iskusnykh IY, Fattakhov N, Li Y, Bihannic L, Kirchner MK, Steshina EY, Northcott PA, Chizhikov VV. Lmx1a is a master regulator of the cortical hem. eLife 2023; 12:e84095. [PMID: 37725078 PMCID: PMC10508884 DOI: 10.7554/elife.84095] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 09/05/2023] [Indexed: 09/21/2023] Open
Abstract
Development of the nervous system depends on signaling centers - specialized cellular populations that produce secreted molecules to regulate neurogenesis in the neighboring neuroepithelium. In some cases, signaling center cells also differentiate to produce key types of neurons. The formation of a signaling center involves its induction, the maintenance of expression of its secreted molecules, and cell differentiation and migration events. How these distinct processes are coordinated during signaling center development remains unknown. By performing studies in mice, we show that Lmx1a acts as a master regulator to orchestrate the formation and function of the cortical hem (CH), a critical signaling center that controls hippocampus development. Lmx1a co-regulates CH induction, its Wnt signaling, and the differentiation and migration of CH-derived Cajal-Retzius neurons. Combining RNAseq, genetic, and rescue experiments, we identified major downstream genes that mediate distinct Lmx1a-dependent processes. Our work revealed that signaling centers in the mammalian brain employ master regulatory genes and established a framework for analyzing signaling center development.
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Affiliation(s)
- Igor Y Iskusnykh
- Department of Anatomy and Neurobiology, University of Tennessee Health Science CenterMemphisUnited States
| | - Nikolai Fattakhov
- Department of Anatomy and Neurobiology, University of Tennessee Health Science CenterMemphisUnited States
| | - Yiran Li
- Department of Developmental Neurobiology, St. Jude Children's Research HospitalMemphisUnited States
| | - Laure Bihannic
- Department of Developmental Neurobiology, St. Jude Children's Research HospitalMemphisUnited States
| | - Matthew K Kirchner
- Department of Anatomy and Neurobiology, University of Tennessee Health Science CenterMemphisUnited States
| | - Ekaterina Y Steshina
- Department of Anatomy and Neurobiology, University of Tennessee Health Science CenterMemphisUnited States
| | - Paul A Northcott
- Department of Developmental Neurobiology, St. Jude Children's Research HospitalMemphisUnited States
| | - Victor V Chizhikov
- Department of Anatomy and Neurobiology, University of Tennessee Health Science CenterMemphisUnited States
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3
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Nguyen H, Sokpor G, Parichha A, Pham L, Saikhedkar N, Xie Y, Ulmke PA, Rosenbusch J, Pirouz M, Behr R, Stoykova A, Brand-Saberi B, Nguyen HP, Staiger JF, Tole S, Tuoc T. BAF (mSWI/SNF) complex regulates mediolateral cortical patterning in the developing forebrain. Front Cell Dev Biol 2022; 10:1011109. [PMID: 36263009 PMCID: PMC9573979 DOI: 10.3389/fcell.2022.1011109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 09/16/2022] [Indexed: 11/24/2022] Open
Abstract
Early forebrain patterning entails the correct regional designation of the neuroepithelium, and appropriate specification, generation, and distribution of neural cells during brain development. Specific signaling and transcription factors are known to tightly regulate patterning of the dorsal telencephalon to afford proper structural/functional cortical arealization and morphogenesis. Nevertheless, whether and how changes of the chromatin structure link to the transcriptional program(s) that control cortical patterning remains elusive. Here, we report that the BAF chromatin remodeling complex regulates the spatiotemporal patterning of the mouse dorsal telencephalon. To determine whether and how the BAF complex regulates cortical patterning, we conditionally deleted the BAF complex scaffolding subunits BAF155 and BAF170 in the mouse dorsal telencephalic neuroepithelium. Morphological and cellular changes in the BAF mutant forebrain were examined using immunohistochemistry and in situ hybridization. RNA sequencing, Co-immunoprecipitation, and mass spectrometry were used to investigate the molecular basis of BAF complex involvement in forebrain patterning. We found that conditional ablation of BAF complex in the dorsal telencephalon neuroepithelium caused expansion of the cortical hem and medial cortex beyond their developmental boundaries. Consequently, the hippocampal primordium is not specified, the mediolateral cortical patterning is compromised, and the cortical identity is disturbed in the absence of BAF complex. The BAF complex was found to interact with the cortical hem suppressor LHX2. The BAF complex suppresses cortical hem fate to permit proper forebrain patterning. We provide evidence that BAF complex modulates mediolateral cortical patterning possibly by interacting with the transcription factor LHX2 to drive the LHX2-dependent transcriptional program essential for dorsal telencephalon patterning. Our data suggest a putative mechanistic synergy between BAF chromatin remodeling complex and LHX2 in regulating forebrain patterning and ontogeny.
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Affiliation(s)
- Huong Nguyen
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
- Faculty of Biotechnology, Thai Nguyen University of Sciences, Thai Nguyen, Vietnam
| | - Godwin Sokpor
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
- Department of Anatomy and Molecular Embryology, Ruhr University Bochum, Bochum, Germany
| | | | - Linh Pham
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
| | | | - Yuanbin Xie
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
| | - Pauline Antonie Ulmke
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
| | - Joachim Rosenbusch
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
| | - Mehdi Pirouz
- Max Planck Institute for Multidisciplinary Sciences, Goettingen, Germany
- Harvard Stem Cell Institute, Harvard Medical School, Boston, MA, United States
| | - Rüdiger Behr
- German Primate Center-Leibniz Institute for Primate Research, Goettingen, Germany
| | | | - Beate Brand-Saberi
- Department of Anatomy and Molecular Embryology, Ruhr University Bochum, Bochum, Germany
| | - Huu Phuc Nguyen
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
| | - Jochen F. Staiger
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
| | - Shubha Tole
- Tata Institute of Fundamental Research, Mumbai, India
- *Correspondence: Shubha Tole, ; Tran Tuoc,
| | - Tran Tuoc
- Institute for Neuroanatomy, University Medical Center, Georg-August-University Goettingen, Goettingen, Germany
- Department of Human Genetics, Ruhr University Bochum, Bochum, Germany
- *Correspondence: Shubha Tole, ; Tran Tuoc,
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Ypsilanti AR, Pattabiraman K, Catta-Preta R, Golonzhka O, Lindtner S, Tang K, Jones IR, Abnousi A, Juric I, Hu M, Shen Y, Dickel DE, Visel A, Pennachio LA, Hawrylycz M, Thompson CL, Zeng H, Barozzi I, Nord AS, Rubenstein JL. Transcriptional network orchestrating regional patterning of cortical progenitors. Proc Natl Acad Sci U S A 2021; 118:e2024795118. [PMID: 34921112 PMCID: PMC8713794 DOI: 10.1073/pnas.2024795118] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/25/2021] [Indexed: 12/23/2022] Open
Abstract
We uncovered a transcription factor (TF) network that regulates cortical regional patterning in radial glial stem cells. Screening the expression of hundreds of TFs in the developing mouse cortex identified 38 TFs that are expressed in gradients in the ventricular zone (VZ). We tested whether their cortical expression was altered in mutant mice with known patterning defects (Emx2, Nr2f1, and Pax6), which enabled us to define a cortical regionalization TF network (CRTFN). To identify genomic programming underlying this network, we performed TF ChIP-seq and chromatin-looping conformation to identify enhancer-gene interactions. To map enhancers involved in regional patterning of cortical progenitors, we performed assays for epigenomic marks and DNA accessibility in VZ cells purified from wild-type and patterning mutant mice. This integrated approach has identified a CRTFN and VZ enhancers involved in cortical regional patterning in the mouse.
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Affiliation(s)
- Athéna R Ypsilanti
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA 94158;
| | - Kartik Pattabiraman
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA 94158
| | - Rinaldo Catta-Preta
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95618
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA 95618
| | - Olga Golonzhka
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA 94158
| | - Susan Lindtner
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA 94158
| | - Ke Tang
- Precise Genome Engineering Center, School of Life Sciences, Guangzhou University, Guangzhou 510006, China
| | - Ian R Jones
- Institute for Human Genetics, University of California, San Francisco, CA 94143
- Department of Neurology, University of California, San Francisco, CA 94143
| | - Armen Abnousi
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195
| | - Ivan Juric
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195
| | - Ming Hu
- Department of Quantitative Health Sciences, Lerner Research Institute, Cleveland Clinic Foundation, Cleveland, OH 44195
| | - Yin Shen
- Institute for Human Genetics, University of California, San Francisco, CA 94143
- Department of Neurology, University of California, San Francisco, CA 94143
| | - Diane E Dickel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
| | - Axel Visel
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- School of Natural Sciences, University of California, Merced, CA 95343
- US Department of Energy Joint Genome Institute, Berkeley, CA 94720
| | - Len A Pennachio
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
- US Department of Energy Joint Genome Institute, Berkeley, CA 94720
- Comparative Biochemistry Program, University of California, Berkeley, CA 94720
| | | | | | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98109
| | - Iros Barozzi
- Faculty of Medicine, Department of Surgery and Cancer, Imperial College, London SW7 2AZ, United Kingdom
| | - Alex S Nord
- Department of Neurobiology, Physiology and Behavior, University of California, Davis, CA 95618
- Department of Psychiatry and Behavioral Sciences, University of California, Davis, CA 95618
| | - John L Rubenstein
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Weill Institute for Neurosciences, University of California, San Francisco, CA 94158;
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Moore SA, Iulianella A. Development of the mammalian cortical hem and its derivatives: the choroid plexus, Cajal-Retzius cells and hippocampus. Open Biol 2021; 11:210042. [PMID: 33947245 PMCID: PMC8097212 DOI: 10.1098/rsob.210042] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/08/2021] [Indexed: 12/14/2022] Open
Abstract
The dorsal medial region of the developing mammalian telencephalon plays a central role in the patterning of the adjacent brain regions. This review describes the development of this specialized region of the vertebrate brain, called the cortical hem, and the formation of the various cells and structures it gives rise to, including the choroid plexus, Cajal-Retzius cells and the hippocampus. We highlight the ontogenic processes that create these different forebrain derivatives from their shared embryonic origin and discuss the key signalling pathways and molecules that influence the patterning of the cortical hem. These include BMP, Wnt, FGF and Shh signalling pathways acting with Homeobox factors to carve the medial telencephalon into district progenitor regions, which in turn give rise to the choroid plexus, dentate gyrus and hippocampus. We then link the formation of the lateral ventricle choroid plexus with embryonic and postnatal neurogenesis in the hippocampus.
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Affiliation(s)
- Samantha A. Moore
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, and Brain Repair Centre, Life Science Research Institute, 1348 Summer Street, Halifax, Nova Scotia, Canada, B3H4R2
| | - Angelo Iulianella
- Department of Medical Neuroscience, Faculty of Medicine, Dalhousie University, and Brain Repair Centre, Life Science Research Institute, 1348 Summer Street, Halifax, Nova Scotia, Canada, B3H4R2
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Spinelli M, Boucard C, Di Nicuolo F, Haesler V, Castellani R, Pontecorvi A, Scambia G, Granieri C, Barnea ER, Surbek D, Mueller M, Di Simone N. Synthetic PreImplantation Factor (sPIF) reduces inflammation and prevents preterm birth. PLoS One 2020; 15:e0232493. [PMID: 32511256 PMCID: PMC7279576 DOI: 10.1371/journal.pone.0232493] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 04/15/2020] [Indexed: 01/05/2023] Open
Abstract
Preterm birth (PTB) is the leading cause of neonatal morbidity and mortality and spontaneous PTB is a major contributor. The preceding inflammation/infection contributes not only to spontaneous PTB but is associated with neonatal morbidities including impaired brain development. Therefore, control of exaggerated immune response during pregnancy is an attractive strategy. A potential candidate is synthetic PreImplantation Factor (sPIF) as sPIF prevents inflammatory induced fetal loss and has neuroprotective properties. Here, we tested maternal sPIF prophylaxis in pregnant mice subjected to a lipopolysaccharides (LPS) insult, which results in PTB. Additionally, we evaluated sPIF effects in placental and microglial cell lines. Maternal sPIF application reduced the LPS induced PTB rate significantly. Consequently, sPIF reduced microglial activation (Iba-1 positive cells) and preserved neuronal migration (Cux-2 positive cells) in fetal brains. In fetal brain lysates sPIF decreased IL-6 and INFγ concentrations. In-vitro, sPIF reduced Iba1 and TNFα expression in microglial cells and reduced the expression of pro-apoptotic (Bad and Bax) and inflammatory (IL-6 and NLRP4) genes in placental cell lines. Together, maternal sPIF prophylaxis prevents PTB in part by controlling exaggerated immune response. Given the sPIF`FDA Fast Track approval in non-pregnant subjects, we envision sPIF therapy in pregnancy.
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Affiliation(s)
- Marialuigia Spinelli
- Department of Obstetrics and Gynecology and Department of Biomedical Research, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Céline Boucard
- Department of Obstetrics and Gynecology and Department of Biomedical Research, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Fiorella Di Nicuolo
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
- International Scientific Institute Paolo VI, Università Cattolica Del Sacro Cuore, A. Gemelli Universitary Hospital, Rome, Italia
| | - Valerie Haesler
- Department of Obstetrics and Gynecology and Department of Biomedical Research, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Roberta Castellani
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
| | - Alfredo Pontecorvi
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
- U.O.C di Endocrinologia e Diabetologia, Dipartimento di Scienze Gastroenterologiche, Endocrino-Metaboliche e Nefro-Urologiche, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia
| | - Giovanni Scambia
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
- U.O.C. di Ginecologia Oncologica, Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli IRCCS, Roma, Italia
| | - Chiara Granieri
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
| | - Eytan R. Barnea
- The Society for The Investigation of Early Pregnancy (SIEP), Cherry Hill, NJ, United States of America
- BioIncept LLC, Cherry Hill, NJ, United States of America
| | - Daniel Surbek
- Department of Obstetrics and Gynecology and Department of Biomedical Research, University Hospital Bern, University of Bern, Bern, Switzerland
| | - Martin Mueller
- Department of Obstetrics and Gynecology and Department of Biomedical Research, University Hospital Bern, University of Bern, Bern, Switzerland
- * E-mail: (MM); (NDS)
| | - Nicoletta Di Simone
- Università Cattolica del Sacro Cuore, Istituto di Clinica Ostetrica e Ginecologica, Roma, Italia
- Dipartimento di Scienze della Salute della Donna e del Bambino, Fondazione Policlinico Universitario A. Gemelli IRCCS, U.O.C. di Ostetricia e Patologia Ostetrica, Roma, Italia
- * E-mail: (MM); (NDS)
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Yang H, Kim J, Kim Y, Jang SW, Sestan N, Shim S. Cux2 expression regulated by Lhx2 in the upper layer neurons of the developing cortex. Biochem Biophys Res Commun 2020; 521:874-879. [PMID: 31708105 DOI: 10.1016/j.bbrc.2019.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2019] [Accepted: 11/01/2019] [Indexed: 12/20/2022]
Abstract
The laminar structure, a unique feature of the mammalian cerebrum, is formed by a number of genes in a highly complex process. The pyramidal neurons that make up each layer of the cerebrum are functionally characterized by specific gene expressions. In particular, Cux1 and Cux2, which are specifically expressed in layer II-IV neurons, are known to regulate dendritic branching, spine morphology, and synapse formation. However, it is still unknown how their expression is regulated transcriptionally. Here we constructed Cux2-mCherry transgenic mice that reproduce the cortical layer II-IV-specific expression of Cux2, a member of the Cut/Cux/CDP family, using BAC transgenesis and a variety of coordinated cortical layer markers that are known to date. Our immunohistochemistry analysis shows that mCherry was expressed in cortical layer II-IV and the corpus callosum in the same way as endogenous Cux2 without ectopic expression. We also identified a region of 220 bp that is highly conserved in mammals and controls specific cerebral expression of Cux2, using comparative genome analysis and in vivo reporter assays. Furthermore, we confirm that Lhx2, whose expression in cortical layer II-IV is similar to that of the Cux2 enhancer, can act as a transcriptional activator. These results suggest that cortical layer II-IV expression of Cux2 can be regulated by the interaction of Cux2-E1 and Lhx2, and that their failure to co-regulate is associated with neurodevelopmental disorders such as autism and schizophrenia.
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Affiliation(s)
- Hayoung Yang
- Department of Biochemistry, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Jiwoo Kim
- Department of Biochemistry, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Yujin Kim
- Department of Biochemistry, Chungbuk National University, Cheongju, 28644, Republic of Korea
| | - Sung-Wuk Jang
- Department of Biomedical Sciences, University of Ulsan College of Medicine, Seoul, 05505, Republic of Korea
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale School of Medicine, New Haven, CT, 06510, USA.
| | - Sungbo Shim
- Department of Biochemistry, Chungbuk National University, Cheongju, 28644, Republic of Korea.
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Yang J, Horton JR, Li J, Huang Y, Zhang X, Blumenthal RM, Cheng X. Structural basis for preferential binding of human TCF4 to DNA containing 5-carboxylcytosine. Nucleic Acids Res 2019; 47:8375-8387. [PMID: 31081034 PMCID: PMC6895265 DOI: 10.1093/nar/gkz381] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 04/27/2019] [Accepted: 04/30/2019] [Indexed: 12/11/2022] Open
Abstract
The psychiatric risk-associated transcription factor 4 (TCF4) is linked to schizophrenia. Rare TCF4 coding variants are found in individuals with Pitt-Hopkins syndrome-an intellectual disability and autism spectrum disorder. TCF4 contains a C-terminal basic-helix-loop-helix (bHLH) DNA binding domain which recognizes the enhancer-box (E-box) element 5'-CANNTG-3' (where N = any nucleotide). A subset of the TCF4-occupancy sites have the expanded consensus binding specificity 5'-C(A/G)-CANNTG-3', with an added outer Cp(A/G) dinucleotide; for example in the promoter for CNIH3, a gene involved in opioid dependence. In mammalian genomes, particularly brain, the CpG and CpA dinucleotides can be methylated at the 5-position of cytosine (5mC), and then may undergo successive oxidations to the 5-hydroxymethyl (5hmC), 5-formyl (5fC), and 5-carboxyl (5caC) forms. We find that, in the context of 5'-0CG-1CA-2CG-3TG-3'(where the numbers indicate successive dinucleotides), modification of the central E-box 2CG has very little effect on TCF4 binding, E-box 1CA modification has a negative influence on binding, while modification of the flanking 0CG, particularly carboxylation, has a strong positive impact on TCF4 binding to DNA. Crystallization of TCF4 in complex with unmodified or 5caC-modified oligonucleotides revealed that the basic region of bHLH domain adopts multiple conformations, including an extended loop going through the DNA minor groove, or the N-terminal portion of a long helix binding in the DNA major groove. The different protein conformations enable arginine 576 (R576) to interact, respectively, with a thymine in the minor groove, a phosphate group of DNA backbone, or 5caC in the major groove. The Pitt-Hopkins syndrome mutations affect five arginine residues in the basic region, two of them (R569 and R576) involved in 5caC recognition. Our analyses indicate, and suggest a structural basis for, the preferential recognition of 5caC by a transcription factor centrally important in brain development.
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Affiliation(s)
- Jie Yang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - John R Horton
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Jia Li
- Center for Epigenetics & Disease Prevention, Institute of Biosciences and Technology, Texas A&M University, Houston, TX 77030, USA
| | - Yun Huang
- Center for Epigenetics & Disease Prevention, Institute of Biosciences and Technology, Texas A&M University, Houston, TX 77030, USA
| | - Xing Zhang
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Robert M Blumenthal
- Department of Medical Microbiology and Immunology, and Program in Bioinformatics, The University of Toledo College of Medicine and Life Sciences, Toledo, OH 43614, USA
| | - Xiaodong Cheng
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
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