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Brien HJ, Lee JC, Sharma J, Hamann CA, Spetz MR, Lippmann ES, Brunger JM. Templated Pluripotent Stem Cell Differentiation via Substratum-Guided Artificial Signaling. ACS Biomater Sci Eng 2024; 10:6465-6482. [PMID: 39352143 DOI: 10.1021/acsbiomaterials.4c00885] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2024]
Abstract
The emerging field of synthetic morphogenesis implements synthetic biology tools to investigate the minimal cellular processes sufficient for orchestrating key developmental events. As the field continues to grow, there is a need for new tools that enable scientists to uncover nuances in the molecular mechanisms driving cell fate patterning that emerge during morphogenesis. Here, we present a platform that combines cell engineering with biomaterial design to potentiate artificial signaling in pluripotent stem cells (PSCs). This platform, referred to as PSC-MATRIX, extends the use of programmable biomaterials to PSCs competent to activate morphogen production through orthogonal signaling, giving rise to the opportunity to probe developmental events by initiating morphogenetic programs in a spatially constrained manner through non-native signaling channels. We show that the PSC-MATRIX platform enables temporal and spatial control of transgene expression in response to bulk, soluble inputs in synthetic Notch (synNotch)-engineered human PSCs for an extended culture of up to 11 days. Furthermore, we used PSC-MATRIX to regulate multiple differentiation events via material-mediated artificial signaling in engineered PSCs using the orthogonal ligand green fluorescent protein, highlighting the potential of this platform for probing and guiding fate acquisition. Overall, this platform offers a synthetic approach to interrogate the molecular mechanisms driving PSC differentiation that could be applied to a variety of differentiation protocols.
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Affiliation(s)
- Hannah J Brien
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Joanne C Lee
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Jhanvi Sharma
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Catherine A Hamann
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Madeline R Spetz
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Ethan S Lippmann
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
- Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
| | - Jonathan M Brunger
- Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee 37235, United States
- Center for Stem Cell Biology, Vanderbilt University, Nashville, Tennessee 37235, United States
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2
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González M, Maurelia F, Aguayo J, Amigo R, Arrué R, Gutiérrez JL, Torrejón M, Farkas C, Caprile T. Uncovering the role of the subcommissural organ in early brain development through transcriptomic analysis. Biol Res 2024; 57:49. [PMID: 39068496 PMCID: PMC11282827 DOI: 10.1186/s40659-024-00524-y] [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: 05/01/2024] [Accepted: 06/14/2024] [Indexed: 07/30/2024] Open
Abstract
BACKGROUND The significant role of embryonic cerebrospinal fluid (eCSF) in the initial stages of brain development has been thoroughly studied. This fluid contains crucial molecules for proper brain development such as members of the Wnt and FGF families, apolipoproteins, and retinol binding protein. Nevertheless, the source of these molecules remains uncertain since they are present before the formation of the choroid plexus, which is conventionally known as the primary producer of cerebrospinal fluid. The subcommissural organ (SCO) is a highly conserved gland located in the diencephalon and is one of the earliest differentiating brain structures. The SCO secretes molecules into the eCSF, prior to the differentiation of the choroid plexus, playing a pivotal role in the homeostasis and dynamics of this fluid. One of the key molecules secreted by the SCO is SCO-spondin, a protein involved in maintenance of the normal ventricle size, straight spinal axis, neurogenesis, and axonal guidance. Furthermore, SCO secretes transthyretin and basic fibroblast growth factor 2, while other identified molecules in the eCSF could potentially be secreted by the SCO. Additionally, various transcription factors have been identified in the SCO. However, the precise mechanisms involved in the early SCO development are not fully understood. RESULTS To uncover key molecular players and signaling pathways involved in the role of the SCO during brain development, we conducted a transcriptomic analysis comparing the embryonic chick SCO at HH23 and HH30 stages (4 and 7 days respectively). Additionally, a public transcriptomic data from HH30 entire chick brain was used to compare expression levels between SCO and whole brain transcriptome. These analyses revealed that, at both stages, the SCO differentially expresses several members of bone morphogenic proteins, Wnt and fibroblast growth factors families, diverse proteins involved in axonal guidance, neurogenic and differentiative molecules, cell receptors and transcription factors. The secretory pathway is particularly upregulated at stage HH30 while the proliferative pathway is increased at stage HH23. CONCLUSION The results suggest that the SCO has the capacity to secrete several morphogenic molecules to the eCSF prior to the development of other structures, such as the choroid plexus.
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Affiliation(s)
- Maryori González
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Felipe Maurelia
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Jaime Aguayo
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Roberto Amigo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Rodrigo Arrué
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - José Leonardo Gutiérrez
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Marcela Torrejón
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile
| | - Carlos Farkas
- Departamento de Ciencias Básicas y Morfología, Facultad de Medicina, Universidad Católica de la Santísima Concepción, Concepción, Chile.
| | - Teresa Caprile
- Departamento de Biología Celular, Facultad de Ciencias Biológicas, Universidad de Concepción, Concepción, Chile.
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Wullimann MF. The Neuromeric/Prosomeric Model in Teleost Fish Neurobiology. BRAIN, BEHAVIOR AND EVOLUTION 2022; 97:336-360. [PMID: 35728561 PMCID: PMC9808694 DOI: 10.1159/000525607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 06/08/2022] [Indexed: 01/07/2023]
Abstract
The neuromeric/prosomeric model has been rejuvenated by Puelles and Rubenstein [Trends Neurosci. 1993;16(11):472-9]. Here, its application to the (teleostean) fish brain is detailed, beginning with a historical account. The second part addresses three main issues with particular interest for fish neuroanatomy and looks at the impact of the neuromeric model on their understanding. The first one is the occurrence of four early migrating forebrain areas (M1 through M4) in teleosts and their comparative interpretation. The second issue addresses the complex development and neuroanatomy of the teleostean alar and basal hypothalamus. The third topic is the vertebrate dopaminergic system, with the focus on some teleostean peculiarities. Most of the information will be coming from zebrafish studies, although the general ductus is a comparative one. Throughout the manuscript, comparative developmental and organizational aspects of the teleostean amygdala are discussed. One particular focus is cellular migration streams into the medial amygdala.
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Affiliation(s)
- Mario F. Wullimann
- Division of Neurobiology, Department Biologie II, Ludwig-Maximilians-Universität München (LMU Munich), Martinsried, Germany,Department Genes-Circuits-Behavior, Max-Planck-Institute for Biological Intelligence (i.F.), Martinsried, Germany,*Mario F. Wullimann,
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4
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Bou-Rouphael J, Durand BC. T-Cell Factors as Transcriptional Inhibitors: Activities and Regulations in Vertebrate Head Development. Front Cell Dev Biol 2021; 9:784998. [PMID: 34901027 PMCID: PMC8651982 DOI: 10.3389/fcell.2021.784998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Accepted: 10/28/2021] [Indexed: 11/22/2022] Open
Abstract
Since its first discovery in the late 90s, Wnt canonical signaling has been demonstrated to affect a large variety of neural developmental processes, including, but not limited to, embryonic axis formation, neural proliferation, fate determination, and maintenance of neural stem cells. For decades, studies have focused on the mechanisms controlling the activity of β-catenin, the sole mediator of Wnt transcriptional response. More recently, the spotlight of research is directed towards the last cascade component, the T-cell factor (TCF)/Lymphoid-Enhancer binding Factor (LEF), and more specifically, the TCF/LEF-mediated switch from transcriptional activation to repression, which in both embryonic blastomeres and mouse embryonic stem cells pushes the balance from pluri/multipotency towards differentiation. It has been long known that Groucho/Transducin-Like Enhancer of split (Gro/TLE) is the main co-repressor partner of TCF/LEF. More recently, other TCF/LEF-interacting partners have been identified, including the pro-neural BarH-Like 2 (BARHL2), which belongs to the evolutionary highly conserved family of homeodomain-containing transcription factors. This review describes the activities and regulatory modes of TCF/LEF as transcriptional repressors, with a specific focus on the functions of Barhl2 in vertebrate brain development. Specific attention is given to the transcriptional events leading to formation of the Organizer, as well as the roles and regulations of Wnt/β-catenin pathway in growth of the caudal forebrain. We present TCF/LEF activities in both embryonic and neural stem cells and discuss how alterations of this pathway could lead to tumors.
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Affiliation(s)
| | - Béatrice C. Durand
- Sorbonne Université, CNRS UMR7622, IBPS Developmental Biology Laboratory, Campus Pierre et Marie Curie, Paris, France
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Bühler A, Carl M. Zebrafish Tools for Deciphering Habenular Network-Linked Mental Disorders. Biomolecules 2021; 11:biom11020324. [PMID: 33672636 PMCID: PMC7924194 DOI: 10.3390/biom11020324] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2021] [Revised: 02/12/2021] [Accepted: 02/14/2021] [Indexed: 11/23/2022] Open
Abstract
Simple Summary Everything that we think, feel or do depends on the function of neural networks in the brain. These are highly complex structures made of cells (neurons) and their interconnections (axons), which develop dependent on precisely coordinated interactions of genes. Any gene mutation can result in unwanted alterations in neural network formation and concomitant brain disorders. The habenula neural network is one of these important circuits, which has been linked to autism, schizophrenia, depression and bipolar disorder. Studies using the zebrafish have uncovered genes involved in the development of this network. Intriguingly, some of these genes have also been identified as risk genes of human brain disorders highlighting the power of this animal model to link risk genes and the affected network to human disease. But can we use the advantages of this model to identify new targets and compounds with ameliorating effects on brain dysfunction? In this review, we summarise the current knowledge on techniques to manipulate the habenula neural network to study the consequences on behavior. Moreover, we give an overview of existing behavioral test to mimic aspects of mental disorders and critically discuss the applicability of the zebrafish model in this field of research. Abstract The prevalence of patients suffering from mental disorders is substantially increasing in recent years and represents a major burden to society. The underlying causes and neuronal circuits affected are complex and difficult to unravel. Frequent disorders such as depression, schizophrenia, autism, and bipolar disorder share links to the habenular neural circuit. This conserved neurotransmitter system relays cognitive information between different brain areas steering behaviors ranging from fear and anxiety to reward, sleep, and social behaviors. Advances in the field using the zebrafish model organism have uncovered major genetic mechanisms underlying the formation of the habenular neural circuit. Some of the identified genes involved in regulating Wnt/beta-catenin signaling have previously been suggested as risk genes of human mental disorders. Hence, these studies on habenular genetics contribute to a better understanding of brain diseases. We are here summarizing how the gained knowledge on the mechanisms underlying habenular neural circuit development can be used to introduce defined manipulations into the system to study the functional behavioral consequences. We further give an overview of existing behavior assays to address phenotypes related to mental disorders and critically discuss the power but also the limits of the zebrafish model for identifying suitable targets to develop therapies.
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Affiliation(s)
- Anja Bühler
- Correspondence: (A.B.); (M.C.); Tel.: +39-0461-282745 (A.B.); +39-0461-283931 (M.C.)
| | - Matthias Carl
- Correspondence: (A.B.); (M.C.); Tel.: +39-0461-282745 (A.B.); +39-0461-283931 (M.C.)
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6
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Wnt Signaling Regulates Ipsilateral Pathfinding in the Zebrafish Forebrain through slit3. Neuroscience 2020; 449:9-20. [DOI: 10.1016/j.neuroscience.2020.09.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2019] [Revised: 09/03/2020] [Accepted: 09/09/2020] [Indexed: 12/21/2022]
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7
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Dawes ML, Soeller C, Scholpp S. Studying molecular interactions in the intact organism: fluorescence correlation spectroscopy in the living zebrafish embryo. Histochem Cell Biol 2020; 154:507-519. [PMID: 33067656 PMCID: PMC7609432 DOI: 10.1007/s00418-020-01930-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2020] [Indexed: 02/07/2023]
Abstract
Cell behaviour and function is determined through the interactions of a multitude of molecules working in concert. To observe these molecular dynamics, biophysical studies have been developed that track single interactions. Fluorescence correlation spectroscopy (FCS) is an optical biophysical technique that non-invasively resolves single molecules through recording the signal intensity at the femtolitre scale. However, recording the behaviour of these biomolecules using in vitro-based assays often fails to recapitulate the full range of variables in vivo that directly confer dynamics. Therefore, there has been an increasing interest in observing the state of these biomolecules within living organisms such as the zebrafish Danio rerio. In this review, we explore the advancements of FCS within the zebrafish and compare and contrast these findings to those found in vitro.
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Affiliation(s)
- Michael L Dawes
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Christian Soeller
- Living Systems Institute, College of Engineering, Mathematics, and Physical Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Steffen Scholpp
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK.
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8
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Choi WY, Hwang JH, Cho AN, Lee AJ, Lee J, Jung I, Cho SW, Kim LK, Kim YJ. DNA Methylation of Intragenic CpG Islands are Required for Differentiation from iPSC to NPC. Stem Cell Rev Rep 2020; 16:1316-1327. [PMID: 32975781 DOI: 10.1007/s12015-020-10041-6] [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] [Accepted: 09/08/2020] [Indexed: 12/30/2022]
Abstract
The effects of gene body DNA methylation on gene regulation still remains highly controversial. In this study, we generated whole genome bisulfite sequencing (WGBS) data with high sequencing depth in induced pluripotent stem cell (iPSC) and neuronal progentior cell (NPC), and investigated the relationship between DNA methylation changes in CpG islands (CGIs) and corresponding gene expression during NPC differentiation. Interestingly, differentially methylated CGIs were more abundant in intragenic regions compared to promoters and these methylated intragenic CGIs (iCGIs) were associated with neuronal development-related genes. When we compared gene expression level of methylated and unmethylated CGIs in intragenic regions, DNA methylation of iCGI was positively correlated with gene expression in contrast with promoter CGIs (pCGIs). To gain insight into regulatory mechanism mediated by iCGI DNA methylation, we executed motif searching in hypermethylated iCGIs and found NEUROD1 as a hypermethylated iCGI binding transcription factor. This study highlights give rise to possibility of activating role of hypermethylation in iCGIs and involvement of neuronal development related TFs. Graphical Abstract The relationship between iCGI DNA methylation and expression of associated genes in neuronal developmental process. During iPSC to NPCdifferentiation, iCGI containing neural developmental genes show iCGI's DNA hypermethylation which is accompanied by gene activation and NEUROD1which is one of the core neuronal TFs interacts with hypermethylated iCGI regions.
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Affiliation(s)
- Won-Young Choi
- Interdisciplinary Program of Integrated OMICS for Biomedical Science, The Graduate School, Yonsei University, Seoul, 03722, Republic of Korea
| | - Ji-Hyun Hwang
- Interdisciplinary Program of Integrated OMICS for Biomedical Science, The Graduate School, Yonsei University, Seoul, 03722, Republic of Korea
| | - Ann-Na Cho
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Andrew J Lee
- Department of Biological Sciences, KAIST, Daejeon, Republic of Korea
| | - Jungwoo Lee
- Interdisciplinary Program of Integrated OMICS for Biomedical Science, The Graduate School, Yonsei University, Seoul, 03722, Republic of Korea
| | - Inkyung Jung
- Department of Biological Sciences, KAIST, Daejeon, Republic of Korea
| | - Seung-Woo Cho
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea
| | - Lark Kyun Kim
- Severance Biomedical Science Institute and BK21 PLUS Project for Medical Sciences, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, 06230, Republic of Korea.
| | - Young-Joon Kim
- Interdisciplinary Program of Integrated OMICS for Biomedical Science, The Graduate School, Yonsei University, Seoul, 03722, Republic of Korea. .,Department of Biochemistry, College of Life Science and Biotechnology, Yonsei University, Seoul, 03722, Republic of Korea.
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9
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Bosze B, Ono Y, Mattes B, Sinner C, Gourain V, Thumberger T, Tlili S, Wittbrodt J, Saunders TE, Strähle U, Schug A, Scholpp S. Pcdh18a regulates endocytosis of E-cadherin during axial mesoderm development in zebrafish. Histochem Cell Biol 2020; 154:463-480. [PMID: 32488346 PMCID: PMC7609436 DOI: 10.1007/s00418-020-01887-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/14/2020] [Indexed: 01/07/2023]
Abstract
The notochord defines the axial structure of all vertebrates during development. Notogenesis is a result of major cell reorganization in the mesoderm, the convergence and the extension of the axial cells. However, it is currently not fully understood how these processes act together in a coordinated way during notochord formation. The prechordal plate is an actively migrating cell population in the central mesoderm anterior to the trailing notochordal plate cells. We show that prechordal plate cells express Protocadherin 18a (Pcdh18a), a member of the cadherin superfamily. We find that Pcdh18a-mediated recycling of E-cadherin adhesion complexes transforms prechordal plate cells into a cohesive and fast migrating cell group. In turn, the prechordal plate cells subsequently instruct the trailing mesoderm. We simulated cell migration during early mesoderm formation using a lattice-based mathematical framework and predicted that the requirement for an anterior, local motile cell cluster could guide the intercalation and extension of the posterior, axial cells. Indeed, a grafting experiment validated the prediction and local Pcdh18a expression induced an ectopic prechordal plate-like cell group migrating towards the animal pole. Our findings indicate that the Pcdh18a is important for prechordal plate formation, which influences the trailing mesodermal cell sheet by orchestrating the morphogenesis of the notochord.
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Affiliation(s)
- Bernadett Bosze
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021, Karlsruhe, Germany
| | - Yosuke Ono
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Benjamin Mattes
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK
| | - Claude Sinner
- Steinbuch Centre for Computing, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76021, Germany.,Department of Physics, Karlsruhe Institute of Technology (KIT), 76021, Karlsruhe, Germany
| | - Victor Gourain
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021, Karlsruhe, Germany
| | - Thomas Thumberger
- Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Sham Tlili
- Mechanobiology Institute, National University of Singapore, Singapore, 117411, Singapore
| | - Joachim Wittbrodt
- Centre for Organismal Studies, Heidelberg University, 69120, Heidelberg, Germany
| | - Timothy E Saunders
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK.,Mechanobiology Institute, National University of Singapore, Singapore, 117411, Singapore
| | - Uwe Strähle
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021, Karlsruhe, Germany
| | - Alexander Schug
- Steinbuch Centre for Computing, Karlsruhe Institute of Technology (KIT), Karlsruhe, 76021, Germany
| | - Steffen Scholpp
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology (KIT), 76021, Karlsruhe, Germany. .,Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, EX4 4QD, UK.
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10
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Guglielmi L, Bühler A, Moro E, Argenton F, Poggi L, Carl M. Temporal control of Wnt signaling is required for habenular neuron diversity and brain asymmetry. Development 2020; 147:147/6/dev182865. [PMID: 32179574 DOI: 10.1242/dev.182865] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Accepted: 02/11/2020] [Indexed: 12/31/2022]
Abstract
Precise temporal coordination of signaling processes is pivotal for cellular differentiation during embryonic development. A vast number of secreted molecules are produced and released by cells and tissues, and travel in the extracellular space. Whether they induce a signaling pathway and instruct cell fate, however, depends on a complex network of regulatory mechanisms, which are often not well understood. The conserved bilateral left-right asymmetrically formed habenulae of the zebrafish are an excellent model for investigating how signaling control facilitates the generation of defined neuronal populations. Wnt signaling is required for habenular neuron type specification, asymmetry and axonal connectivity. The temporal regulation of this pathway and the players involved have, however, have remained unclear. We find that tightly regulated temporal restriction of Wnt signaling activity in habenular precursor cells is crucial for the diversity and asymmetry of habenular neuron populations. We suggest a feedback mechanism whereby the tumor suppressor Wnt inhibitory factor Wif1 controls the Wnt dynamics in the environment of habenular precursor cells. This mechanism might be common to other cell types, including tumor cells.
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Affiliation(s)
- Luca Guglielmi
- Heidelberg University, Medical Faculty Mannheim, Department of Cell and Molecular Biology, 68167 Mannheim, Germany.
| | - Anja Bühler
- University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), 38123 Trento, Italy.
| | - Enrico Moro
- University of Padova, Department of Molecular Medicine, 35121 Padova, Italy
| | | | - Lucia Poggi
- University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), 38123 Trento, Italy.
| | - Matthias Carl
- Heidelberg University, Medical Faculty Mannheim, Department of Cell and Molecular Biology, 68167 Mannheim, Germany. ,University of Trento, Department of Cellular, Computational and Integrative Biology (CIBIO), 38123 Trento, Italy.
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11
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Dahiya S, Saini V, Kumar P, Kumar A. Protein-Protein interaction network analyses of human WNT proteins involved in neural development. Bioinformation 2019; 15:307-314. [PMID: 31249432 PMCID: PMC6589473 DOI: 10.6026/97320630015307] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2019] [Accepted: 04/09/2019] [Indexed: 11/23/2022] Open
Abstract
WNT proteins are involved from initial of neural tissue specification to the end of cell fate determination and organ development. The
present work was carried out to understand the involvement of different WNT isoforms (WNT3a, WNT5a and WNT7b) in neural
development. A total of 718, 546 and 1004 PPIs for WNT3a, WNT5a and WNT7b respectively, were predicted by STRING database with
confidence score more than 0.400. A network carrying all the selected PPIs of targeted proteins was constructed by using Cytoscape by
assigning source node, target node and combined score as edge attribute. A total 2268 interactions of WNT3a, WNT5a and WNT7b were
predicted to be involved in multiple signaling pathways and developmental processes. 43 of 2268 PPIs were refined after analyzing role of
targeted proteins specifically in brain and neural development. WNT3a, WNT5a and WNT7a were predicted to be interacting with 18, 17
and 11 proteins, respectively, with average node degree score of 1.89, 2.12 and 1.82 respectively. The CytoHubba algorithm identified
WNT3a, WNT5a, and WNT7b as hub proteins in neural development ranked on the basis of EPC (Edge Percolated Component) score of
9.352, 9.258 and 8.387.
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Affiliation(s)
- Sween Dahiya
- Toxicology and Computational Biology Group, Centre for Bioinformatics, M. D. University, Rohtak, Haryana 124001 India
| | - Vandana Saini
- Toxicology and Computational Biology Group, Centre for Bioinformatics, M. D. University, Rohtak, Haryana 124001 India
| | - Pawan Kumar
- Toxicology and Computational Biology Group, Centre for Bioinformatics, M. D. University, Rohtak, Haryana 124001 India
| | - Ajit Kumar
- Toxicology and Computational Biology Group, Centre for Bioinformatics, M. D. University, Rohtak, Haryana 124001 India
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12
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Poggi L, Casarosa S, Carl M. An Eye on the Wnt Inhibitory Factor Wif1. Front Cell Dev Biol 2018; 6:167. [PMID: 30574494 PMCID: PMC6292148 DOI: 10.3389/fcell.2018.00167] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2018] [Accepted: 11/23/2018] [Indexed: 12/11/2022] Open
Abstract
The coordinated interplay between extrinsic activating and repressing cell signaling molecules is pivotal for embryonic development and subsequent tissue homeostasis. This is well exemplified by studies on the evolutionarily conserved Wnt signaling pathways. Tight temporal and spatial regulation of Wnt signaling activity is required throughout lifetime, from maternal stages before gastrulation until and throughout adulthood. Outside cells, the action of numerous Wnt ligands is counteracted and fine-tuned by only a handful of well characterized secreted inhibitors, such as for instance Dickkopf, secreted Frizzled Related Proteins and Cerberus. Here, we give an overview of our current understanding of another secreted Wnt signaling antagonist, the Wnt inhibitory factor Wif1. Wif1 can directly interact with various Wnt ligands and inhibits their binding to membrane bound receptors. Epigenetic promoter methylation of Wif1, leading to silencing of its transcription and concomitant up-regulation of Wnt signaling, is a common feature during cancer progression. Furthermore, an increasing number of reports describe Wif1 involvement in regulating processes during embryonic development, which so far has not received as much attention. We will summarize our knowledge on Wif1 function and its mode of action with a particular focus on the zebrafish (Danio rerio). In addition, we highlight the potential of Wif1 research to understand and possibly influence mechanisms underlying eye diseases and regeneration.
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Affiliation(s)
- Lucia Poggi
- Laboratory of Molecular and Cellular Ophthalmology, Centre for Integrative Biology, University of Trento, Trento, Italy
| | - Simona Casarosa
- Laboratory of Neural Development and Regeneration, Centre for Integrative Biology, University of Trento, Trento, Italy
| | - Matthias Carl
- Laboratory of Translational Neurogenetics, Centre for Integrative Biology, University of Trento, Trento, Italy
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Mattes B, Dang Y, Greicius G, Kaufmann LT, Prunsche B, Rosenbauer J, Stegmaier J, Mikut R, Özbek S, Nienhaus GU, Schug A, Virshup DM, Scholpp S. Wnt/PCP controls spreading of Wnt/β-catenin signals by cytonemes in vertebrates. eLife 2018; 7:36953. [PMID: 30060804 PMCID: PMC6086664 DOI: 10.7554/elife.36953] [Citation(s) in RCA: 89] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2018] [Accepted: 07/16/2018] [Indexed: 12/31/2022] Open
Abstract
Signaling filopodia, termed cytonemes, are dynamic actin-based membrane structures that regulate the exchange of signaling molecules and their receptors within tissues. However, how cytoneme formation is regulated remains unclear. Here, we show that Wnt/planar cell polarity (PCP) autocrine signaling controls the emergence of cytonemes, and that cytonemes subsequently control paracrine Wnt/β-catenin signal activation. Upon binding of the Wnt family member Wnt8a, the receptor tyrosine kinase Ror2 becomes activated. Ror2/PCP signaling leads to the induction of cytonemes, which mediate the transport of Wnt8a to neighboring cells. In the Wnt-receiving cells, Wnt8a on cytonemes triggers Wnt/β-catenin-dependent gene transcription and proliferation. We show that cytoneme-based Wnt transport operates in diverse processes, including zebrafish development, murine intestinal crypt and human cancer organoids, demonstrating that Wnt transport by cytonemes and its control via the Ror2 pathway is highly conserved in vertebrates. Communication helps the cells that make up tissues and organs to work together as a team. One way that cells share information with each other as tissues grow and develop is by exchanging signaling proteins. These interact with receptors on the surface of other cells; this causes the cell to change how it behaves. The Wnt family of signaling proteins orchestrate organ development. Wnt proteins influence which types of cells develop, how fast they divide, and how and when they move. Relatively few cells, or small groups of cells, in developing tissues produce Wnt proteins, while larger groups nearby respond to the signals. We do not fully understand how Wnt proteins travel between cells, but recent work revealed an unexpected mechanism – cells seem to hand-deliver their messages. Finger-like structures called cytonemes grow out of the cell membrane and carry Wnt proteins to their destination. If the cytonemes do not form properly the target cells do not behave correctly, which can lead to severe tissue malformation. Mattes et al. have now investigated how cytonemes form using a combination of state-of-the-art genetic and high-resolution imaging techniques. In initial experiments involving zebrafish cells that were grown in the laboratory, Mattes et al. found that the Wnt proteins kick start their own transport; before they travel to their destination, they act on the cells that made them. A Wnt protein called Wnt8a activates the receptor Ror2 on the surface of the signal-producing cell. Ror2 then triggers signals inside the cell that begin the assembly of the cytonemes. The more Ror2 is activated, the more cytonemes the cell makes, and the more Wnt signals it can send out. This mechanism operates in various tissues: Ror2 also controls the cytoneme transport process in living zebrafish embryos, the mouse intestine and human stomach tumors. This knowledge will help researchers to develop new ways to control Wnt signaling, which could help to produce new treatments for diseases ranging from cancers (for example in the stomach and bowel) to degenerative diseases such as Alzheimer’s disease.
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Affiliation(s)
- Benjamin Mattes
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom.,Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Yonglong Dang
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Gediminas Greicius
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | | | - Benedikt Prunsche
- Institute of Applied Physics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Jakob Rosenbauer
- John von Neumann Institute for Computing, Jülich Supercomputing Centre, Jülich, Germany
| | - Johannes Stegmaier
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Imaging and Computer Vision, RWTH Aachen University, Aachen, Germany
| | - Ralf Mikut
- Institute for Automation and Applied Informatics, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Suat Özbek
- Centre of Organismal Studies, University of Heidelberg, Karlsruhe, Germany
| | - Gerd Ulrich Nienhaus
- Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Applied Physics, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Institute of Nanotechnology, Karlsruhe Institute of Technology, Karlsruhe, Germany.,Department of Physics, University of Illinois at Urbana-Champaign, Urbana, United States
| | - Alexander Schug
- John von Neumann Institute for Computing, Jülich Supercomputing Centre, Jülich, Germany.,Steinbuch Centre for Computing, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - David M Virshup
- Program in Cancer and Stem Cell Biology, Duke-NUS Medical School, Singapore, Singapore
| | - Steffen Scholpp
- Living Systems Institute, School of Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom.,Institute of Toxicology and Genetics, Karlsruhe Institute of Technology, Karlsruhe, Germany
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14
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Newman EA, Wu D, Taketo MM, Zhang J, Blackshaw S. Canonical Wnt signaling regulates patterning, differentiation and nucleogenesis in mouse hypothalamus and prethalamus. Dev Biol 2018; 442:236-248. [PMID: 30063881 DOI: 10.1016/j.ydbio.2018.07.021] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/26/2018] [Accepted: 07/26/2018] [Indexed: 01/10/2023]
Abstract
The hypothalamus is a small, but anatomically and functionally complex region of the brain whose development is poorly understood. In this study, we have explored its development by studying the canonical Wnt signaling pathway, generating gain and loss of function mutations of beta-catenin (Ctnnb1) in both hypothalamic and prethalamic neuroepithelium. Deletion of Ctnnb1 resulted in an anteriorized and hypoplastic hypothalamus. Posterior structures were lost or reduced, and anterior structures were expanded. In contrast, overexpression of a constitutively active mutant form of Ctnnb1 resulted in severe hyperplasia of prethalamus and hypothalamus, and expanded expression of a subset of posterior and premamillary hypothalamic markers. Moderate defects in differentiation of Arx-positive GABAergic neural precursors were observed in both prethalamus and hypothalamus of Ctnnb1 loss of function mutants, while in gain of function mutants, their differentiation was completely suppressed, although markers of prethalamic progenitors were preserved. Multiple other region-specific markers, including several specific posterior hypothalamic structures, were also suppressed in Ctnnb1 gain of function mutations. Severe, region-specific defects in hypothalamic nucleogenesis were also observed in both gain and loss of function mutations of Ctnnb1. Finally, both gain and loss of function of Ctnnb1 also produced severe, non-cell autonomous disruptions of pituitary development. These findings demonstrate a central and multifaceted role for canonical Wnt signaling in regulating growth, patterning, differentiation and nucleogenesis in multiple diencephalic regions.
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Affiliation(s)
- Elizabeth A Newman
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dan Wu
- Department of Radiology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Makoto Mark Taketo
- Division of Experimental Therapeutics, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Jiangyang Zhang
- Department of Radiology, NYU Langone School of Medicine, New York, NY, USA
| | - Seth Blackshaw
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Center for Human Systems Biology, Johns Hopkins University School of Medicine, Baltimore, MD, USA; Institute for Cell Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
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15
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Rai-Bhogal R, Wong C, Kissoondoyal A, Davidson J, Li H, Crawford DA. Maternal exposure to prostaglandin E 2 modifies expression of Wnt genes in mouse brain - An autism connection. Biochem Biophys Rep 2018; 14:43-53. [PMID: 29872733 PMCID: PMC5986660 DOI: 10.1016/j.bbrep.2018.03.012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 03/28/2018] [Accepted: 03/31/2018] [Indexed: 11/03/2022] Open
Abstract
Prostaglandin E2 (PGE2) is a lipid signaling molecule important for brain development and function. Various genetic and environmental factors can influence the level of PGE2 and increase the risk of developing Autism Spectrum Disorder (ASD). We have previously shown that in neuronal cell lines and mouse brain, PGE2 can interfere with the Wnt canonical pathway, which is essential during early brain development. Higher levels of PGE2 increased Wnt-dependent motility and proliferation of neuroectodermal stem cells, and modified the expression of Wnt genes previously linked to autism disorders. We also recently established a cross-talk between these two pathways in the prenatal mouse brain lacking PGE2 producing enzyme (COX-/-). The current study complements the published data and reveals that PGE2 signaling also converges with the Wnt canonical pathway in the developing mouse brain after maternal exposure to PGE2 at the onset of neurogenesis. We found significant changes in the expression level of Wnt-target genes, Mmp7, Wnt2, and Wnt3a, during prenatal and early postnatal stages. Interestingly, we observed variability in the expression level of these genes between genetically-identical pups within the same pregnancy. Furthermore, we found that all the affected genes have been previously associated with disorders of the central nervous system, including autism. We determined that prenatal exposure to PGE2 affects the Wnt pathway at the level of β-catenin, the major downstream regulator of Wnt-dependent gene transcription. We discuss how these results add new knowledge into the molecular mechanisms by which PGE2 may interfere with neuronal development during critical periods.
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Affiliation(s)
- Ravneet Rai-Bhogal
- Neuroscience Graduate Diploma Program, York University, Toronto, ON, Canada M3J 1P3.,Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Christine Wong
- Neuroscience Graduate Diploma Program, York University, Toronto, ON, Canada M3J 1P3.,School of Kinesiology and Health Science, York University, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
| | - Ashby Kissoondoyal
- Neuroscience Graduate Diploma Program, York University, Toronto, ON, Canada M3J 1P3.,School of Kinesiology and Health Science, York University, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
| | - Jennilee Davidson
- Neuroscience Graduate Diploma Program, York University, Toronto, ON, Canada M3J 1P3.,Department of Biology, York University, Toronto, ON, Canada M3J 1P3
| | - Hongyan Li
- School of Kinesiology and Health Science, York University, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
| | - Dorota A Crawford
- Neuroscience Graduate Diploma Program, York University, Toronto, ON, Canada M3J 1P3.,Department of Biology, York University, Toronto, ON, Canada M3J 1P3.,School of Kinesiology and Health Science, York University, 4700 Keele Street, Toronto, ON, Canada M3J 1P3
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16
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Hübner K, Grassme KS, Rao J, Wenke NK, Zimmer CL, Korte L, Müller K, Sumanas S, Greber B, Herzog W. Wnt signaling positively regulates endothelial cell fate specification in the Fli1a-positive progenitor population via Lef1. Dev Biol 2017; 430:142-155. [DOI: 10.1016/j.ydbio.2017.08.004] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2017] [Revised: 08/03/2017] [Accepted: 08/03/2017] [Indexed: 01/06/2023]
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17
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Lee M, Yoon J, Song H, Lee B, Lam DT, Yoon J, Baek K, Clevers H, Jeong Y. Tcf7l2 plays crucial roles in forebrain development through regulation of thalamic and habenular neuron identity and connectivity. Dev Biol 2017; 424:62-76. [DOI: 10.1016/j.ydbio.2017.02.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/16/2017] [Accepted: 02/16/2017] [Indexed: 11/28/2022]
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18
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Gezelius H, López-Bendito G. Thalamic neuronal specification and early circuit formation. Dev Neurobiol 2016; 77:830-843. [PMID: 27739248 DOI: 10.1002/dneu.22460] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2016] [Revised: 09/16/2016] [Accepted: 10/10/2016] [Indexed: 12/12/2022]
Abstract
The thalamus is a central structure of the brain, primarily recognized for the relay of incoming sensory and motor information to the cerebral cortex but also key in high order intracortical communication. It consists of glutamatergic projection neurons organized in several distinct nuclei, each having a stereotype connectivity pattern and functional roles. In the adult, these nuclei can be appreciated by architectural boundaries, although their developmental origin and specification is only recently beginning to be revealed. Here, we summarize the current knowledge on the specification of the distinct thalamic neurons and nuclei, starting from early embryonic patterning until the postnatal days when active sensory experience is initiated and the overall system connectivity is already established. We also include an overview of the guidance processes important for establishing thalamocortical connections, with emphasis on the early topographical specification. The extensively studied thalamocortical axon branching in the cortex is briefly mentioned; however, the maturation and plasticity of this connection are beyond the scope of this review. In separate chapters, additional mechanisms and/or features that influence the specification and development of thalamic neurons and their circuits are also discussed. Finally, an outlook of future directions is given. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 830-843, 2017.
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Affiliation(s)
- Henrik Gezelius
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Spain
| | - Guillermina López-Bendito
- Instituto de Neurociencias de Alicante, Universidad Miguel Hernández-Consejo Superior de Investigaciones Científicas (UMH-CSIC), Avenida Ramón y Cajal, s/n, Sant Joan d'Alacant, Spain
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19
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Sena E, Feistel K, Durand BC. An Evolutionarily Conserved Network Mediates Development of the zona limitans intrathalamica, a Sonic Hedgehog-Secreting Caudal Forebrain Signaling Center. J Dev Biol 2016; 4:jdb4040031. [PMID: 29615594 PMCID: PMC5831802 DOI: 10.3390/jdb4040031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Revised: 09/29/2016] [Accepted: 10/13/2016] [Indexed: 12/16/2022] Open
Abstract
Recent studies revealed new insights into the development of a unique caudal forebrain-signaling center: the zona limitans intrathalamica (zli). The zli is the last brain signaling center to form and the first forebrain compartment to be established. It is the only part of the dorsal neural tube expressing the morphogen Sonic Hedgehog (Shh) whose activity participates in the survival, growth and patterning of neuronal progenitor subpopulations within the thalamic complex. Here, we review the gene regulatory network of transcription factors and cis-regulatory elements that underlies formation of a shh-expressing delimitated domain in the anterior brain. We discuss evidence that this network predates the origin of chordates. We highlight the contribution of Shh, Wnt and Notch signaling to zli development and discuss implications for the fact that the morphogen Shh relies on primary cilia for signal transduction. The network that underlies zli development also contributes to thalamus induction, and to its patterning once the zli has been set up. We present an overview of the brain malformations possibly associated with developmental defects in this gene regulatory network (GRN).
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Affiliation(s)
- Elena Sena
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
| | - Kerstin Feistel
- Institute of Zoology, University of Hohenheim, Garbenstr. 30, 70593 Stuttgart, Germany.
| | - Béatrice C Durand
- Institut Curie, Université Paris Sud, INSERM U1021, CNRS UMR3347, Centre Universitaire, Bâtiment 110, F-91405 Orsay Cedex, France.
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20
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Wong CT, Ussyshkin N, Ahmad E, Rai-Bhogal R, Li H, Crawford DA. Prostaglandin E2promotes neural proliferation and differentiation and regulates Wnt target gene expression. J Neurosci Res 2016; 94:759-75. [DOI: 10.1002/jnr.23759] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2015] [Revised: 04/06/2016] [Accepted: 04/06/2016] [Indexed: 12/11/2022]
Affiliation(s)
- Christine T. Wong
- School of Kinesiology and Health Science; York University; Toronto Ontario Canada
- Neuroscience Graduate Diploma Program; York University; Toronto Ontario Canada
| | - Netta Ussyshkin
- Department of Biology; York University; Toronto Ontario Canada
| | - Eizaaz Ahmad
- Neuroscience Graduate Diploma Program; York University; Toronto Ontario Canada
- Department of Biology; York University; Toronto Ontario Canada
| | - Ravneet Rai-Bhogal
- Neuroscience Graduate Diploma Program; York University; Toronto Ontario Canada
- Department of Biology; York University; Toronto Ontario Canada
| | - Hongyan Li
- School of Kinesiology and Health Science; York University; Toronto Ontario Canada
| | - Dorota A. Crawford
- School of Kinesiology and Health Science; York University; Toronto Ontario Canada
- Neuroscience Graduate Diploma Program; York University; Toronto Ontario Canada
- Department of Biology; York University; Toronto Ontario Canada
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21
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Histone H4 acetylation and the epigenetic reader Brd4 are critical regulators of pluripotency in embryonic stem cells. BMC Genomics 2016; 17:95. [PMID: 26847871 PMCID: PMC4740988 DOI: 10.1186/s12864-016-2414-y] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 01/26/2016] [Indexed: 12/14/2022] Open
Abstract
Background Pluripotent cells can be differentiated into many different cell types in vitro. Successful differentiation is guided in large part by epigenetic reprogramming and regulation of critical gene expression patterns. Recent genome-wide studies have identified the distribution of different histone-post-translational modifications (PTMs) in various conditions and during cellular differentiation. However, our understanding of the abundance of histone PTMs and their regulatory mechanisms still remain unknown. Results Here, we present a quantitative and comprehensive study of the abundance levels of histone PTMs during the differentiation of mouse embryonic stem cells (ESCs) using mass spectrometry (MS). We observed dynamic changes of histone PTMs including increased H3K9 methylation levels in agreement with previously reported results. More importantly, we found a global decrease of multiply acetylated histone H4 peptides. Brd4 targets acetylated H4 with a strong affinity to multiply modified H4 acetylation sites. We observed that the protein levels of Brd4 decreased upon differentiation together with global histone H4 acetylation. Inhibition of Brd4:histone H4 interaction by the BET domain inhibitor (+)-JQ1 in ESCs results in enhanced differentiation to the endodermal lineage, by disrupting the protein abundance dynamics. Genome-wide ChIP-seq mapping showed that Brd4 and H4 acetylation are co-occupied in the genome, upstream of core pluripotency genes such as Oct4 and Nanog in ESCs and lineage-specific genes in embryoid bodies (EBs). Conclusions Together, our data demonstrate the fundamental role of Brd4 in monitoring cell differentiation through its interaction with acetylated histone marks and disruption of Brd4 may cause aberrant differentiation. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2414-y) contains supplementary material, which is available to authorized users.
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22
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Baranowska Körberg I, Hofmeister W, Markljung E, Cao J, Nilsson D, Ludwig M, Draaken M, Holmdahl G, Barker G, Reutter H, Vukojević V, Clementson Kockum C, Lundin J, Lindstrand A, Nordenskjöld A. WNT3 involvement in human bladder exstrophy and cloaca development in zebrafish. Hum Mol Genet 2015; 24:5069-78. [DOI: 10.1093/hmg/ddv225] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2015] [Accepted: 06/12/2015] [Indexed: 01/16/2023] Open
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23
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Juraver-Geslin HA, Durand BC. Early development of the neural plate: new roles for apoptosis and for one of its main effectors caspase-3. Genesis 2015; 53:203-24. [PMID: 25619400 DOI: 10.1002/dvg.22844] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2014] [Accepted: 01/07/2015] [Indexed: 12/12/2022]
Abstract
Despite its tremendous complexity, the vertebrate nervous system emerges from a homogenous layer of neuroepithelial cells, the neural plate. Its formation relies on the time- and space-controlled progression of developmental programs. Apoptosis is a biological process that removes superfluous and potentially dangerous cells and is implemented through the activation of a molecular pathway conserved during evolution. Apoptosis and an unconventional function of one of its main effectors, caspase-3, contribute to the patterning and growth of the neuroepithelium. Little is known about the intrinsic and extrinsic cues controlling activities of the apoptotic machinery during development. The BarH-like (Barhl) proteins are homeodomain-containing transcription factors. The observations in Caenorhabditis elegans, Xenopus, and mice document that Barhl proteins act in cell survival and as cell type-specific regulators of a caspase-3 function that limits neural progenitor proliferation. In this review, we discuss the roles and regulatory modes of the apoptotic machinery in the development of the neural plate. We focus on the Barhl2, the Sonic Hedgehog, and the Wnt pathways and their activities in neural progenitor survival and proliferation.
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Affiliation(s)
- Hugo A Juraver-Geslin
- Department of Basic Science, Craniofacial Biology, College of Dentistry, New York University, New York, New York
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24
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Klarić T, Lardelli M, Key B, Koblar S, Lewis M. Activity-dependent expression of neuronal PAS domain-containing protein 4 (npas4a) in the developing zebrafish brain. Front Neuroanat 2014; 8:148. [PMID: 25538572 PMCID: PMC4255624 DOI: 10.3389/fnana.2014.00148] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 11/18/2014] [Indexed: 11/26/2022] Open
Abstract
In rodents, the Npas4 gene has recently been identified as being an important regulator of synaptic plasticity and memory. Homologs of Npas4 have been found in invertebrate species though their functions appear to be too divergent for them to be studied as a proxy for the mammalian proteins. The aim of this study, therefore, was to ascertain the suitability of the zebrafish as a model organism for investigating the function of Npas4 genes. We show here that the expression and regulation of the zebrafish Npas4 homolog, npas4a, is remarkably similar to that of the rodent Npas4 genes. As in mammals, expression of the zebrafish npas4a gene is restricted to the brain where it is up-regulated in response to neuronal activity. Furthermore, we also show that knockdown of npas4a during embryonic development results in a number of forebrain-specific defects including increased apoptosis and misexpression of the forebrain marker genes dlx1a and shha. Our work demonstrates that the zebrafish is a suitable model organism for investigating the role of the npas4a gene and one that is likely to provide valuable insights into the function of the mammalian homologs. Furthermore, our findings highlight a potential role for npas4a in forebrain development.
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Affiliation(s)
- Thomas Klarić
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Michael Lardelli
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
| | - Brian Key
- School of Biomedical Sciences, The University of Queensland Brisbane, QLD, Australia
| | - Simon Koblar
- School of Medicine, The University of Adelaide Adelaide, SA, Australia
| | - Martin Lewis
- School of Molecular and Biomedical Sciences, The University of Adelaide Adelaide, SA, Australia
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25
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Juraver-Geslin HA, Gómez-Skarmeta JL, Durand BC. The conserved barH-like homeobox-2 gene barhl2 acts downstream of orthodentricle-2 and together with iroquois-3 in establishment of the caudal forebrain signaling center induced by Sonic Hedgehog. Dev Biol 2014; 396:107-20. [PMID: 25281935 DOI: 10.1016/j.ydbio.2014.09.027] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2014] [Revised: 08/13/2014] [Accepted: 09/23/2014] [Indexed: 01/01/2023]
Abstract
In this study, we investigated the gene regulatory network that governs formation of the Zona limitans intrathalamica (ZLI), a signaling center that secretes Sonic Hedgehog (Shh) to control the growth and regionalization of the caudal forebrain. Using loss- and gain-of-function, explants and grafting experiments in amphibians, we demonstrate that barhl2 acts downstream of otx2 and together with the iroquois (irx)-3 gene in establishment of the ZLI compartment initiated by Shh influence. We find that the presumptive (pre)-ZLI domain expresses barhl2, otx2 and irx3, whereas the thalamus territory caudally bordering the pre-ZLI expresses barhl2, otx2 and irx1/2 and early on irx3. We demonstrate that Barhl2 activity is required for determination of the ZLI and thalamus fates and that within the p2 alar plate the ratio of Irx3 to Irx1/2 contributes to ZLI specification and size determination. We show that when continuously exposed to Shh, neuroepithelial cells coexpressing barhl2, otx2 and irx3 acquire two characteristics of the ZLI compartment-the competence to express shh and the ability to segregate from anterior neural plate cells. In contrast, neuroepithelial cells expressing barhl2, otx2 and irx1/2, are not competent to express shh. Noteworthy in explants, under Shh influence, ZLI-like cells segregate from thalamic-like cells. Our study establishes that Barhl2 activity plays a key role in p2 alar plate patterning, specifically ZLI formation, and provides new insights on establishment of the signaling center of the caudal forebrain.
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Affiliation(s)
- Hugo A Juraver-Geslin
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, S1.7 46 rue d'Ulm 75005, Paris F-75005, France; INSERM, U1024, Paris F-75005, France; CNRS, UMR 8197, Paris F-75005, France; S1.7 46 rue d'Ulm, 75005 Paris, France
| | - José Luis Gómez-Skarmeta
- Centro Andaluz de Biología del Desarrollo-CSIC/Universidad Pablo de Olavide, Carretera de Utrera, Km1, 41013 Sevilla, Spain
| | - Béatrice C Durand
- Ecole Normale Supérieure, Institut de Biologie de l'ENS, IBENS, S1.7 46 rue d'Ulm 75005, Paris F-75005, France; INSERM, U1024, Paris F-75005, France; CNRS, UMR 8197, Paris F-75005, France; S1.7 46 rue d'Ulm, 75005 Paris, France.
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26
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Cavodeassi F. Integration of anterior neural plate patterning and morphogenesis by the Wnt signaling pathway. Dev Neurobiol 2013; 74:759-71. [PMID: 24115566 DOI: 10.1002/dneu.22135] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2013] [Revised: 09/13/2013] [Accepted: 09/23/2013] [Indexed: 01/08/2023]
Abstract
Wnts are essential for a multitude of processes during embryonic development and adult homeostasis. The molecular structure of the Wnt pathway is extremely complex, and it keeps growing as new molecular components and novel interactions are uncovered. Recent studies have advanced our understanding on how the diverse molecular outcomes of the Wnt pathway are integrated during organ development, an integration that is also essential, although mechanistically poorly understood, during the formation of the anterior part of the nervous system, the forebrain. In this article, the author has summarized these findings and discussed their implications for forebrain development. A special emphasis has been put forth on studies performed in the zebrafish as this model system has been instrumental for our current understanding of forebrain patterning.
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Affiliation(s)
- Florencia Cavodeassi
- Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Nicolás Cabrera 1, 28049, Madrid, Spain
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Beretta CA, Dross N, Bankhead P, Carl M. The ventral habenulae of zebrafish develop in prosomere 2 dependent on Tcf7l2 function. Neural Dev 2013; 8:19. [PMID: 24067090 PMCID: PMC3827927 DOI: 10.1186/1749-8104-8-19] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2013] [Accepted: 07/23/2013] [Indexed: 11/10/2022] Open
Abstract
Background The conserved habenular neural circuit relays cognitive information from the forebrain into the ventral mid- and hindbrain. In zebrafish, the bilaterally formed habenulae in the dorsal diencephalon are made up of the asymmetric dorsal and symmetric ventral habenular nuclei, which are homologous to the medial and lateral nuclei respectively, in mammals. These structures have been implicated in various behaviors related to the serotonergic/dopaminergic neurotransmitter system. The dorsal habenulae develop adjacent to the medially positioned pineal complex. Their precursors differentiate into two main neuronal subpopulations which differ in size across brain hemispheres as signals from left-sided parapineal cells influence their differentiation program. Unlike the dorsal habenulae and despite their importance, the ventral habenulae have been poorly studied. It is not known which genetic programs underlie their development and why they are formed symmetrically, unlike the dorsal habenulae. A main reason for this lack of knowledge is that the vHb origin has remained elusive to date. Results To address these questions, we applied long-term 2-photon microscopy time-lapse analysis of habenular neural circuit development combined with depth color coding in a transgenic line, labeling all main components of the network. Additional laser ablations and cell tracking experiments using the photoconvertible PSmOrange system in GFP transgenic fish show that the ventral habenulae develop in prosomere 2, posterior and lateral to the dorsal habenulae in the dorsal thalamus. Mutant analysis demonstrates that the ventral habenular nuclei only develop in the presence of functional Tcf7l2, a downstream modulator of the Wnt signaling cascade. Consistently, photoconverted thalamic tcf7l2exl/exl mutant cells do not contribute to habenula formation. Conclusions We show in vivo that dorsal and ventral habenulae develop in different regions of prosomere 2. In the process of ventral habenula formation, functional tcf7l2 gene activity is required and in its absence, ventral habenular neurons do not develop. Influenced by signals from parapineal cells, dorsal habenular neurons differentiate at a time at which ventral habenular cells are still on their way towards their final destination. Thus, our finding may provide a simple explanation as to why only neuronal populations of the dorsal habenulae differ in size across brain hemispheres.
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Affiliation(s)
- Carlo A Beretta
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, Mannheim 68167, Germany.
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Hagenlocher C, Walentek P, M Ller C, Thumberger T, Feistel K. Ciliogenesis and cerebrospinal fluid flow in the developing Xenopus brain are regulated by foxj1. Cilia 2013; 2:12. [PMID: 24229449 PMCID: PMC3848805 DOI: 10.1186/2046-2530-2-12] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Accepted: 09/03/2013] [Indexed: 11/29/2022] Open
Abstract
Background Circulation of cerebrospinal fluid (CSF) through the ventricular system is driven by motile cilia on ependymal cells of the brain. Disturbed ciliary motility induces the formation of hydrocephalus, a pathological accumulation of CSF resulting in ventricle dilatation and increased intracranial pressure. The mechanism by which loss of motile cilia causes hydrocephalus has not been elucidated. The aim of this study was: (1) to provide a detailed account of the development of ciliation in the brain of the African clawed frog Xenopus laevis; and (2) to analyze the relevance of ependymal cilia motility for CSF circulation and brain ventricle morphogenesis in Xenopus. Methods Gene expression analysis of foxj1, the bona fide marker for motile cilia, was used to identify potentially ciliated regions in the developing central nervous system (CNS) of the tadpole. Scanning electron microscopy (SEM) was used to reveal the distribution of mono- and multiciliated cells during successive stages of brain morphogenesis, which was functionally assessed by bead injection and video microscopy of ventricular CSF flow. An antisense morpholino oligonucleotide (MO)-mediated gene knock-down that targeted foxj1 in the CNS was applied to assess the role of motile cilia in the ventricles. Results RNA transcripts of foxj1 in the CNS were found from neurula stages onwards. Following neural tube closure, foxj1 expression was seen in distinct ventricular regions such as the zona limitans intrathalamica (ZLI), subcommissural organ (SCO), floor plate, choroid plexus (CP), and rhombomere boundaries. In all areas, expression of foxj1 preceded the outgrowth of monocilia and the subsequent switch to multiciliated ependymal cells. Cilia were absent in foxj1 morphants, causing impaired CSF flow and fourth ventricle hydrocephalus in tadpole-stage embryos. Conclusions Motile ependymal cilia are important organelles in the Xenopus CNS, as they are essential for the circulation of CSF and maintenance of homeostatic fluid pressure. The Xenopus CNS ventricles might serve as a novel model system for the analysis of human ciliary genes whose deficiency cause hydrocephalus.
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Affiliation(s)
- Cathrin Hagenlocher
- Institute of Zoology, University of Hohenheim, Garbenstr, 30, Stuttgart 70593, Germany.
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Schmidt R, Strähle U, Scholpp S. Neurogenesis in zebrafish - from embryo to adult. Neural Dev 2013; 8:3. [PMID: 23433260 PMCID: PMC3598338 DOI: 10.1186/1749-8104-8-3] [Citation(s) in RCA: 216] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Accepted: 01/17/2013] [Indexed: 01/19/2023] Open
Abstract
Neurogenesis in the developing central nervous system consists of the induction and proliferation of neural progenitor cells and their subsequent differentiation into mature neurons. External as well as internal cues orchestrate neurogenesis in a precise temporal and spatial way. In the last 20 years, the zebrafish has proven to be an excellent model organism to study neurogenesis in the embryo. Recently, this vertebrate has also become a model for the investigation of adult neurogenesis and neural regeneration. Here, we summarize the contributions of zebrafish in neural development and adult neurogenesis.
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Affiliation(s)
- Rebecca Schmidt
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics, 76021, Karlsruhe, Germany
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Efremov AN, Stanganello E, Welle A, Scholpp S, Levkin PA. Micropatterned superhydrophobic structures for the simultaneous culture of multiple cell types and the study of cell–cell communication. Biomaterials 2013; 34:1757-63. [PMID: 23228425 DOI: 10.1016/j.biomaterials.2012.11.034] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 11/20/2012] [Indexed: 12/22/2022]
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Beccari L, Marco-Ferreres R, Bovolenta P. The logic of gene regulatory networks in early vertebrate forebrain patterning. Mech Dev 2012; 130:95-111. [PMID: 23111324 DOI: 10.1016/j.mod.2012.10.004] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2012] [Accepted: 10/09/2012] [Indexed: 01/19/2023]
Abstract
The vertebrate forebrain or prosencephalon is patterned at the beginning of neurulation into four major domains: the telencephalic, hypothalamic, retinal and diencephalic anlagen. These domains will then give rise to the majority of the brain structures involved in sensory integration and the control of higher intellectual and homeostatic functions. Understanding how forebrain pattering arises has thus attracted the interest of developmental neurobiologists for decades. As a result, most of its regulators have been identified and their hierarchical relationship is now the object of active investigation. Here, we summarize the main morphogenetic pathways and transcription factors involved in forebrain specification and propose the backbone of a possible gene regulatory network (GRN) governing its specification, taking advantage of the GRN principles elaborated by pioneer studies in simpler organisms. We will also discuss this GRN and its operational logic in the context of the remarkable morphological and functional diversification that the forebrain has undergone during evolution.
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Affiliation(s)
- Leonardo Beccari
- Centro de Biología Molecular "Severo Ochoa", CSIC-UAM, c/Nicolas Cabrera, 1, Madrid 28049, Spain
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Mulligan KA, Cheyette BNR. Wnt signaling in vertebrate neural development and function. J Neuroimmune Pharmacol 2012; 7:774-87. [PMID: 23015196 DOI: 10.1007/s11481-012-9404-x] [Citation(s) in RCA: 104] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2012] [Accepted: 09/10/2012] [Indexed: 02/03/2023]
Abstract
Members of the Wnt family of secreted signaling proteins influence many aspects of neural development and function. Wnts are required from neural induction and axis formation to axon guidance and synapse development, and even help modulate synapse activity. Wnt proteins activate a variety of downstream signaling pathways and can induce a similar variety of cellular responses, including gene transcription changes and cytoskeletal rearrangements. This review provides an introduction to Wnt signaling pathways and discusses current research on their roles in vertebrate neural development and function.
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Affiliation(s)
- Kimberly A Mulligan
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA 94158, USA
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Hagemann AIH, Scholpp S. The Tale of the Three Brothers - Shh, Wnt, and Fgf during Development of the Thalamus. Front Neurosci 2012; 6:76. [PMID: 22654733 PMCID: PMC3361129 DOI: 10.3389/fnins.2012.00076] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 05/04/2012] [Indexed: 12/19/2022] Open
Abstract
The thalamic complex is an essential part of the brain that requires a combination of specialized activities to attain its final complexity. In the following review we will describe the induction process of the mid-diencephalic organizer (MDO) where three different signaling pathways merge: Wnt, Shh, and Fgf. Here, we dissect the function of each signaling pathway in the thalamus in chronological order of their appearance. First we describe the Wnt mediated induction of the MDO and compartition of the caudal forebrain, then the Shh mediated determination of proneural gene expression before discussing recent progress in characterizing Fgf function during thalamus development. Then, we focus on transcription factors, which are regulated by these pathways and which play a pivotal role in neurogenesis in the thalamus. The three signaling pathways act together in a strictly regulated chronology to orchestrate the development of the entire thalamus.
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Affiliation(s)
- Anja I H Hagemann
- Karlsruhe Institute of Technology, Institute of Toxicology and Genetics Karlsruhe, Germany
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Martinez-Ferre A, Martinez S. Molecular regionalization of the diencephalon. Front Neurosci 2012; 6:73. [PMID: 22654731 PMCID: PMC3360461 DOI: 10.3389/fnins.2012.00073] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Accepted: 05/03/2012] [Indexed: 01/29/2023] Open
Abstract
The anatomic complexity of the diencephalon depends on precise molecular and cellular regulative mechanisms orchestrated by regional morphogenetic organizers at the neural tube stage. In the diencephalon, like in other neural tube regions, dorsal and ventral signals codify positional information to specify ventro-dorsal regionalization. Retinoic acid, Fgf8, BMPs, and Wnts signals are the molecular factors acting upon the diencephalic epithelium to specify dorsal structures, while Shh is the main ventralizing signal. A central diencephalic organizer, the zona limitans intrathalamica (ZLI), appears after neurulation in the central diencephalic alar plate, establishing additional antero-posterior positional information inside diencephalic alar plate. Based on Shh expression, the ZLI acts as a morphogenetic center, which cooperates with other signals in thalamic specification and pattering in the alar plate of diencephalon. Indeed, Shh is expressed first in the basal plate extending dorsally through the ZLI epithelium as the development proceeds. Despite the importance of ZLI in diencephalic morphogenesis the mechanisms that regulate its development remain incompletely understood. Actually, controversial interpretations in different experimental models have been proposed. That is, experimental results have suggested that (i) the juxtaposition of the molecularly heterogeneous neuroepithelial areas, (ii) cell reorganization in the epithelium, and/or (iii) planar and vertical inductions in the neural epithelium, are required for ZLI specification and development. We will review some experimental data to approach the study of the molecular regulation of diencephalic regionalization, with special interest in the cellular mechanisms underlying planar inductions.
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Chatterjee M, Li JYH. Patterning and compartment formation in the diencephalon. Front Neurosci 2012; 6:66. [PMID: 22593732 PMCID: PMC3349951 DOI: 10.3389/fnins.2012.00066] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 04/17/2012] [Indexed: 01/03/2023] Open
Abstract
The diencephalon gives rise to structures that play an important role in connecting the anterior forebrain with the rest of the central nervous system. The thalamus is the major diencephalic derivative that functions as a relay station between the cortex and other lower order sensory systems. Almost two decades ago, neuromeric/prosomeric models were proposed describing the subdivision and potential segmentation of the diencephalon. Unlike the laminar structure of the cortex, the diencephalon is progressively divided into distinct functional compartments consisting principally of thalamus, epithalamus, pretectum, and hypothalamus. Neurons generated within these domains further aggregate to form clusters called nuclei, which form specific structural and functional units. We review the recent advances in understanding the genetic mechanisms that are involved in the patterning and compartment formation of the diencephalon.
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Affiliation(s)
- Mallika Chatterjee
- Department of Genetics and Developmental Biology, University of Connecticut Health Center Farmington, CT, USA
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