1
|
Chatzi D, Kyriakoudi SA, Dermitzakis I, Manthou ME, Meditskou S, Theotokis P. Clinical and Genetic Correlation in Neurocristopathies: Bridging a Precision Medicine Gap. J Clin Med 2024; 13:2223. [PMID: 38673496 PMCID: PMC11050951 DOI: 10.3390/jcm13082223] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 04/09/2024] [Accepted: 04/10/2024] [Indexed: 04/28/2024] Open
Abstract
Neurocristopathies (NCPs) encompass a spectrum of disorders arising from issues during the formation and migration of neural crest cells (NCCs). NCCs undergo epithelial-mesenchymal transition (EMT) and upon key developmental gene deregulation, fetuses and neonates are prone to exhibit diverse manifestations depending on the affected area. These conditions are generally rare and often have a genetic basis, with many following Mendelian inheritance patterns, thus making them perfect candidates for precision medicine. Examples include cranial NCPs, like Goldenhar syndrome and Axenfeld-Rieger syndrome; cardiac-vagal NCPs, such as DiGeorge syndrome; truncal NCPs, like congenital central hypoventilation syndrome and Waardenburg syndrome; and enteric NCPs, such as Hirschsprung disease. Additionally, NCCs' migratory and differentiating nature makes their derivatives prone to tumors, with various cancer types categorized based on their NCC origin. Representative examples include schwannomas and pheochromocytomas. This review summarizes current knowledge of diseases arising from defects in NCCs' specification and highlights the potential of precision medicine to remedy a clinical phenotype by targeting the genotype, particularly important given that those affected are primarily infants and young children.
Collapse
Affiliation(s)
| | | | | | | | | | - Paschalis Theotokis
- Department of Histology-Embryology, School of Medicine, Aristotle University of Thessaloniki, 54124 Thessaloniki, Greece; (D.C.); (S.A.K.); (I.D.); (M.E.M.); (S.M.)
| |
Collapse
|
2
|
McDonald NA, Tao L, Dong MQ, Shen K. SAD-1 kinase controls presynaptic phase separation by relieving SYD-2/Liprin-α autoinhibition. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.12.544643. [PMID: 37398223 PMCID: PMC10312667 DOI: 10.1101/2023.06.12.544643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Neuronal development orchestrates the formation of an enormous number of synapses that connect the nervous system. In developing presynapses, the core active zone structure has been found to assemble through a liquid-liquid phase separation. Here, we find that the phase separation of SYD-2/Liprin-α, a key active zone scaffold, is controlled by phosphorylation. Using phosphoproteomics, we identify the SAD-1 kinase to phosphorylate SYD-2 and a number of other substrates. Presynaptic assembly is impaired in sad-1 mutants and increased by overactivation of SAD-1. We determine SAD-1 phosphorylation of SYD-2 at three sites is critical to activate its phase separation. Mechanistically, phosphorylation relieves a binding interaction between two folded SYD-2 domains that inhibits phase separation by an intrinsically disordered region. We find synaptic cell adhesion molecules localize SAD-1 to nascent synapses upstream of active zone formation. We conclude that SAD-1 phosphorylates SYD-2 at developing synapses, enabling its phase separation and active zone assembly.
Collapse
Affiliation(s)
| | - Li Tao
- Department of Biology, Stanford University, Stanford, CA, USA
| | - Meng-Qiu Dong
- National Institute of Biological Sciences, Beijing, China
| | - Kang Shen
- Department of Biology, Stanford University, Stanford, CA, USA
- Howard Hughes Medical Institute, Stanford University, Stanford, CA, USA
| |
Collapse
|
3
|
Song H, Morrow BE. Tbx2 and Tbx3 regulate cell fate progression of the otic vesicle for inner ear development. Dev Biol 2023; 494:71-84. [PMID: 36521641 PMCID: PMC9870991 DOI: 10.1016/j.ydbio.2022.12.003] [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: 10/05/2022] [Revised: 12/05/2022] [Accepted: 12/10/2022] [Indexed: 12/14/2022]
Abstract
The morphogenesis of the otic vesicle (OV) to form inner ear organs serves as an excellent model system to understand cell fate acquisition on a single cell level. Tbx2 and Tbx3 (Tbx2/3) encode closely related T-box transcription factors that are expressed widely in the mammalian OV. Inactivation of both genes in the OV (Tbx2/3cKO) results in failed morphogenesis into inner ear organs. To understand the basis of these defects, single cell RNA-sequencing (scRNA-seq) was performed on the OV lineage, in controls versus Tbx2/3cKO embryos. We identified a multipotent population termed otic progenitors in controls that are marked by expression of the known otic placode markers Eya1, Sox2, and Sox3 as well as new markers Fgf18, Cxcl12, and Pou3f3. The otic progenitor population was increased three-fold in Tbx2/3cKO embryos, concomitant with dysregulation of genes in these cells as well as reduced progression to more differentiated states of prosensory and nonsensory cells. An ectopic neural population of cells was detected in the posterior OV of Tbx2/3cKO embryos but had reduced maturation to delaminated neural cells. As all three cell fates were affected in Tbx2/3cKO embryos, we suggest that Tbx2/3 promotes progression of multipotent otic progenitors to more differentiated cell types in the OV.
Collapse
Affiliation(s)
- Hansoo Song
- Department of Genetics, Albert Einstein College of Medicine, 1301 Morris Park Ave., Bronx, NY, USA
| | - Bernice E Morrow
- Department of Genetics, Albert Einstein College of Medicine, 1301 Morris Park Ave., Bronx, NY, USA.
| |
Collapse
|
4
|
Adolescent Congenital Central Hypoventilation Syndrome: An Easily Overlooked Diagnosis. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph182413402. [PMID: 34949014 PMCID: PMC8703802 DOI: 10.3390/ijerph182413402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/12/2021] [Accepted: 12/14/2021] [Indexed: 11/17/2022]
Abstract
Congenital central hypoventilation syndrome (CCHS), also known as Ondine’s curse, is a rare, potentially fatal genetic disease, manifesting as a lack of respiratory drive. Most diagnoses are made in pediatric patients, however late-onset cases have been rarely reported. Due to the milder symptoms at presentation that might easily go overlooked, these late-onset cases can result in serious health consequences later in life. Here, we present a case report of late-onset CCHS in an adolescent female patient. In this review we summarize the current knowledge about symptoms, as well as clinical management of CCHS, and describe in detail the molecular mechanism responsible for this disorder.
Collapse
|
5
|
Ho R, Workman MJ, Mathkar P, Wu K, Kim KJ, O'Rourke JG, Kellogg M, Montel V, Banuelos MG, Arogundade OA, Diaz-Garcia S, Oheb D, Huang S, Khrebtukova I, Watson L, Ravits J, Taylor K, Baloh RH, Svendsen CN. Cross-Comparison of Human iPSC Motor Neuron Models of Familial and Sporadic ALS Reveals Early and Convergent Transcriptomic Disease Signatures. Cell Syst 2020; 12:159-175.e9. [PMID: 33382996 DOI: 10.1016/j.cels.2020.10.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 08/10/2020] [Accepted: 11/18/2020] [Indexed: 12/11/2022]
Abstract
Induced pluripotent stem cell (iPSC)-derived neural cultures from amyotrophic lateral sclerosis (ALS) patients can model disease phenotypes. However, heterogeneity arising from genetic and experimental variability limits their utility, impacting reproducibility and the ability to track cellular origins of pathogenesis. Here, we present methodologies using single-cell RNA sequencing (scRNA-seq) analysis to address these limitations. By repeatedly differentiating and applying scRNA-seq to motor neurons (MNs) from healthy, familial ALS, sporadic ALS, and genome-edited iPSC lines across multiple patients, batches, and platforms, we account for genetic and experimental variability toward identifying unified and reproducible ALS signatures. Combining HOX and developmental gene expression with global clustering, we anatomically classified cells into rostrocaudal, progenitor, and postmitotic identities. By relaxing statistical thresholds, we discovered genes in iPSC-MNs that were concordantly dysregulated in postmortem MNs and yielded predictive ALS markers in other human and mouse models. Our approach thus revealed early, convergent, and MN-resolved signatures of ALS.
Collapse
Affiliation(s)
- Ritchie Ho
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Department of Biomedical Sciences, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
| | - Michael J Workman
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Pranav Mathkar
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Kathryn Wu
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Kevin J Kim
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Jacqueline G O'Rourke
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | | | | | - Maria G Banuelos
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | | | - Sandra Diaz-Garcia
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | - Daniel Oheb
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Steven Huang
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | | | | | - John Ravits
- Department of Neurosciences, University of California, San Diego, La Jolla, CA 92093, USA
| | | | - Robert H Baloh
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Center for Neural Science and Medicine, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA; Department of Neurology, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA
| | - Clive N Svendsen
- Board of Governors Regenerative Medicine Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048, USA.
| |
Collapse
|
6
|
Molecular Profiling Defines Evolutionarily Conserved Transcription Factor Signatures of Major Vestibulospinal Neuron Groups. eNeuro 2019; 6:eN-NWR-0475-18. [PMID: 30899776 PMCID: PMC6426439 DOI: 10.1523/eneuro.0475-18.2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/04/2019] [Accepted: 01/25/2019] [Indexed: 12/24/2022] Open
Abstract
Vestibulospinal neurons are organized into discrete groups projecting from brainstem to spinal cord, enabling vertebrates to maintain proper balance and posture. The two largest groups are the lateral vestibulospinal tract (LVST) group and the contralateral medial vestibulospinal tract (cMVST) group, with different projection lateralities and functional roles. In search of a molecular basis for these differences, we performed RNA sequencing on LVST and cMVST neurons from mouse and chicken embryos followed by immunohistofluorescence validation. Focusing on transcription factor (TF)-encoding genes, we identified TF signatures that uniquely distinguish the LVST from the cMVST group and further parse different rhombomere-derived portions comprising the cMVST group. Immunohistofluorescence assessment of the CNS from spinal cord to cortex demonstrated that these TF signatures are restricted to the respective vestibulospinal groups and some neurons in their immediate vicinity. Collectively, these results link the combinatorial expression of TFs to developmental and functional subdivisions within the vestibulospinal system.
Collapse
|
7
|
Rios-Pilier J, Krimm RF. TrkB expression and dependence divides gustatory neurons into three subpopulations. Neural Dev 2019; 14:3. [PMID: 30691513 PMCID: PMC6350382 DOI: 10.1186/s13064-019-0127-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 01/07/2019] [Indexed: 01/01/2023] Open
Abstract
Background During development, gustatory (taste) neurons likely undergo numerous changes in morphology and expression prior to differentiation into maturity, but little is known this process or the factors that regulate it. Neuron differentiation is likely regulated by a combination of transcription and growth factors. Embryonically, most geniculate neuron development is regulated by the growth factor brain derived neurotrophic factor (BDNF). Postnatally, however, BDNF expression becomes restricted to subpopulations of taste receptor cells with specific functions. We hypothesized that during development, the receptor for BDNF, tropomyosin kinase B receptor (TrkB), may also become developmentally restricted to a subset of taste neurons and could be one factor that is differentially expressed across taste neuron subsets. Methods We used transgenic mouse models to label both geniculate neurons innervating the oral cavity (Phox2b+), which are primarily taste, from those projecting to the outer ear (auricular neurons) to label TrkB expressing neurons (TrkBGFP). We also compared neuron number, taste bud number, and taste receptor cell types in wild-type animals and conditional TrkB knockouts. Results Between E15.5-E17.5, TrkB receptor expression becomes restricted to half of the Phox2b + neurons. This TrkB downregulation was specific to oral cavity projecting neurons, since TrkB expression remained constant throughout development in the auricular geniculate neurons (Phox2b-). Conditional TrkB removal from oral sensory neurons (Phox2b+) reduced this population to 92% of control levels, indicating that only 8% of these neurons do not depend on TrkB for survival during development. The remaining neurons failed to innervate any remaining taste buds, 14% of which remained despite the complete loss of innervation. Finally, some types of taste receptor cells (Car4+) were more dependent on innervation than others (PLCβ2+). Conclusions Together, these findings indicate that TrkB expression and dependence divides gustatory neurons into three subpopulations: 1) neurons that always express TrkB and are TrkB-dependent during development (50%), 2) neurons dependent on TrkB during development but that downregulate TrkB expression between E15.5 and E17.5 (41%), and 3) neurons that never express or depend on TrkB (9%). These TrkB-independent neurons are likely non-gustatory, as they do not innervate taste buds.
Collapse
Affiliation(s)
- Jennifer Rios-Pilier
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, 511 S. Floyd St., MDR Building Room 111, Louisville, KY, 40202, USA
| | - Robin F Krimm
- Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, 511 S. Floyd St., MDR Building Room 111, Louisville, KY, 40202, USA.
| |
Collapse
|
8
|
Puelles L, Tvrdik P, Martínez-de-la-torre M. The Postmigratory Alar Topography of Visceral Cranial Nerve Efferents Challenges the Classical Model of Hindbrain Columns. Anat Rec (Hoboken) 2018; 302:485-504. [DOI: 10.1002/ar.23830] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 12/07/2017] [Accepted: 12/08/2017] [Indexed: 12/21/2022]
Affiliation(s)
- Luis Puelles
- Department of Human Anatomy and Psychobiology and IMIB-Arrixaca Institute, School of Medicine; University of Murcia; Murcia 30071 Spain
| | - Petr Tvrdik
- Department of Neurosurgery-Physiology; University of Utah; Salt Lake City, Utah 84112
| | - Margaret Martínez-de-la-torre
- Department of Human Anatomy and Psychobiology and IMIB-Arrixaca Institute, School of Medicine; University of Murcia; Murcia 30071 Spain
| |
Collapse
|
9
|
Hoekstra EJ, von Oerthel L, van der Linden AJA, Smidt MP. Phox2b influences the development of a caudal dopaminergic subset. PLoS One 2012; 7:e52118. [PMID: 23251691 PMCID: PMC3522650 DOI: 10.1371/journal.pone.0052118] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2012] [Accepted: 11/08/2012] [Indexed: 12/01/2022] Open
Abstract
The developing mesodiencephalic dopaminergic (mdDA) neuronal field can be subdivided into several molecularly distinct domains that arise due to spatiotemporally distinct origins of the neurons and distinct transcriptional pathways controlling these neuronal subsets. Two large anatomically and functionally different subdomains are formed that eventually give rise to the SNc and VTA, but more subsets exist which require detailed characterization in order to better understand the development of the functionally different mdDA subsets, and subset-specific vulnerability. In this study, we aimed to characterize the role of transcription factor Phox2b in the development of mdDA neurons. We provide evidence that Phox2b is co-expressed with TH in a dorsal-caudal subset of neurons in the mdDA neuronal field during embryonic development. Moreover, Phox2b transcripts were identified in FAC-sorted Pitx3 positive neurons. Subsequent analysis of Phox2b mutant embryos revealed that in the absence of Phox2b, a decrease of TH expression occurred specifically in the midbrain neuronal subset that normally co-expresses Phox2b with TH. Our data suggest that Phox2b is, next to the known role in the development of the oculomotor complex, involved in the development of a specific caudal mdDA neuronal subset.
Collapse
Affiliation(s)
- Elisa J. Hoekstra
- Neuroscience and Pharmacology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Lars von Oerthel
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Annemarie J. A. van der Linden
- Neuroscience and Pharmacology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
| | - Marten P. Smidt
- Neuroscience and Pharmacology, Rudolf Magnus Institute of Neuroscience, University Medical Center Utrecht, Utrecht, The Netherlands
- Center for Neuroscience, Swammerdam Institute for Life Sciences, University of Amsterdam, Amsterdam, The Netherlands
- * E-mail:
| |
Collapse
|
10
|
Zhang B, Chen B, Wu T, Xuan Z, Zhu X, Chen R. Estimating developmental states of tumors and normal tissues using a linear time-ordered model. BMC Bioinformatics 2011; 12:53. [PMID: 21310084 PMCID: PMC3223864 DOI: 10.1186/1471-2105-12-53] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2010] [Accepted: 02/11/2011] [Indexed: 11/18/2022] Open
Abstract
Background Tumor cells are considered to have an aberrant cell state, and some evidence indicates different development states appearing in the tumorigenesis. Embryonic development and stem cell differentiation are ordered processes in which the sequence of events over time is highly conserved. The "cancer attractor" concept integrates normal developmental processes and tumorigenesis into a high-dimensional "cell state space", and provides a reasonable explanation of the relationship between these two biological processes from theoretical viewpoint. However, it is hard to describe such relationship by using existed experimental data; moreover, the measurement of different development states is also difficult. Results Here, by applying a novel time-ordered linear model based on a co-bisector which represents the joint direction of a series of vectors, we described the trajectories of development process by a line and showed different developmental states of tumor cells from developmental timescale perspective in a cell state space. This model was used to transform time-course developmental expression profiles of human ESCs, normal mouse liver, ovary and lung tissue into "cell developmental state lines". Then these cell state lines were applied to observe the developmental states of different tumors and their corresponding normal samples. Mouse liver and ovarian tumors showed different similarity to early development stage. Similarly, human glioma cells and ovarian tumors became developmentally "younger". Conclusions The time-ordered linear model captured linear projected development trajectories in a cell state space. Meanwhile it also reflected the change tendency of gene expression over time from the developmental timescale perspective, and our finding indicated different development states during tumorigenesis processes in different tissues.
Collapse
Affiliation(s)
- Bo Zhang
- Laboratory of Bioinformatics and Noncoding RNA, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, PR China
| | | | | | | | | | | |
Collapse
|
11
|
Blugeon C, Le Crom S, Richard L, Vallat JM, Charnay P, Decker L. Dok4 is involved in Schwann cell myelination and axonal interaction in vitro. Glia 2010; 59:351-62. [DOI: 10.1002/glia.21106] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2010] [Revised: 09/20/2010] [Accepted: 10/12/2010] [Indexed: 12/22/2022]
|
12
|
Sun X, Jiang R, Zhang Y, Chen M, Xiang P, Qi Y, Gao Q, Huang B, Ge J. Gene expression and differentiation characteristics in mice E13.5 and E17.5 neural retinal progenitors. Mol Vis 2009; 15:2503-14. [PMID: 19960071 PMCID: PMC2787307] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Accepted: 11/25/2009] [Indexed: 11/01/2022] Open
Abstract
PURPOSE Retinal progenitor cells (RPCs) are the most valuable seed cells in replacement therapy for neural retinal diseases. The competence of RPCs changes with retinal development. Gene expression plays a fundamental role in determining the competence. To improve the selection of the right-timing RPCs for replacement therapy, we compared the gene expression between embryonic day (E) 13.5 and E17.5 RPCs and further explored their gene expression and differentiation capacity in vitro. METHODS Timed-pregnant E13.5 and E17.5 RPCs were freshly harvested and cultured in proliferation conditions for 4 days and then in differentiation conditions for 8 days. At different time points, the expression of key genes involved in retinal development was investigated by quantitative reverse transcription-PCR or immunofluorescence. RESULTS The expression of 14 key genes involved in retinal development was investigated in freshly harvested E13.5 and E17.5 RPCs. The freshly harvested E13.5 RPCs showed a high expression of retinal ganglion cell (RGC)-related genes, including Math5, Brn3b, Islet1, and Nfl, while the freshly harvested E17.5 RPCs displayed a high expression for Nrl, GFAP, and Thy1, the key genes involved in rod photoreceptor development, glial cell development, and synaptogenesis, respectively. During proliferation culture in vitro, the gene expression changed dramatically in both RPCs. After the 4 days of proliferation culture, the expression levels of most genes (11 of the 14 genes) in E13.5 RPCs came close to those in the freshly harvested E17.5 RPCs. Differentiation of RPCs in vitro was verified by the significant decrease in Nestin expression and BruU incorporation efficiency. After the 8 days of differentiation in vitro, the expression level of RGC-related genes (Math5, Brn3b, and Islet1) was still significantly higher in E13.5 RPCs than in E17.5 RPCs. In contrast, the expression level of Nrl and GFAP was significantly higher in E17.5 RPCs than in E13.5 RPCs. In morphology, the differentiated E13.5 RPCs displayed more robust process outgrowth than did the differentiated E17.5 RPCs. Immunofluorescence showed that, after the 8 days of differentiation, E13.5 RPCs contained more Brn3b- and Map2-positive cells, while E17.5 RPCs contained more GFAP-, GS-, and Rhodopsin-positive cells. CONCLUSIONS The results implied that E13.5 RPCs might be a better choice for RGC replacement therapy, while E17.5 RPCs might be better for photoreceptor replacement therapy. The duration of in vitro culture should be timed, since the expression of key genes kept changing in the proliferating RPCs.
Collapse
Affiliation(s)
- Xuerong Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China,Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University, Guangzhou, China
| | - Ruzhang Jiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China,Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University, Guangzhou, China
| | - Yuehong Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Mengfei Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China,Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University, Guangzhou, China
| | - Peng Xiang
- Center for Stem Cell Biology and Tissue Engineering, Sun Yat-sen University, Guangzhou, China
| | - Ying Qi
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Qianying Gao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Bing Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jian Ge
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| |
Collapse
|
13
|
Chambers D, Wilson LJ, Alfonsi F, Hunter E, Saxena U, Blanc E, Lumsden A. Rhombomere-specific analysis reveals the repertoire of genetic cues expressed across the developing hindbrain. Neural Dev 2009; 4:6. [PMID: 19208226 PMCID: PMC2649922 DOI: 10.1186/1749-8104-4-6] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2008] [Accepted: 02/10/2009] [Indexed: 11/24/2022] Open
Abstract
Background The Hox family of homeodomain transcription factors comprises pivotal regulators of cell specification and identity during animal development. However, despite their well-defined roles in the establishment of anteroposterior pattern and considerable research into their mechanism of action, relatively few target genes have been identified in the downstream regulatory network. We have sought to investigate this issue, focussing on the developing hindbrain and the cranial motor neurons that arise from this region. The reiterated anteroposterior compartments of the developing hindbrain (rhombomeres (r)) are normally patterned by the combinatorial action of distinct Hox genes. Alteration in the normal pattern of Hox cues in this region results in a transformation of cellular identity to match the remaining Hox profile, similar to that observed in Drosophila homeotic transformations. Results To define the repertoire of genes regulated in each rhombomere, we have analysed the transcriptome of each rhombomere from wild-type mouse embryos and not those where pattern is perturbed by gain or loss of Hox gene function. Using microarray and bioinformatic methodologies in conjunction with other confirmatory techniques, we report here a detailed and comprehensive set of potential Hox target genes in r2, r3, r4 and r5. We have demonstrated that the data produced are both fully reflective and predictive of rhombomere identity and, thus, may represent some the of Hox targets. These data have been interrogated to generate a list of candidate genes whose function may contribute to the generation of neuronal subtypes characteristic of each rhombomere. Interestingly, the data can also be classified into genetic motifs that are predicted by the specific combinations of Hox genes and other regulators of hindbrain anteroposterior identity. The sets of genes described in each or combinations of rhombomeres span a wide functional range and suggest that the Hox genes, as well as other regulatory inputs, exert their influence across the full spectrum of molecular machinery. Conclusion We have performed a systematic survey of the transcriptional status of individual segments of the developing mouse hindbrain and identified hundreds of previously undescribed genes expressed in this region. The functional range of the potential candidate effectors or upstream modulators of Hox activity suggest multiple unexplored mechanisms. In particular, we present evidence of a potential new retinoic acid signalling system in ventral r4 and propose a model for the refinement of identity in this region. Furthermore, the rhombomeres demonstrate a molecular relationship to each other that is consistent with known observations about neurogenesis in the hindbrain. These findings give the first genome-wide insight into the complexity of gene expression during patterning of the developing hindbrain.
Collapse
Affiliation(s)
- David Chambers
- MRC Centre for Developmental Neurobiology, King's College London, UK.
| | | | | | | | | | | | | |
Collapse
|
14
|
Zhongling Feng, Gang Zhao, Lei Yu. Neural stem cells and Alzheimer's disease: challenges and hope. Am J Alzheimers Dis Other Demen 2009; 24:52-7. [PMID: 19116300 PMCID: PMC10846222 DOI: 10.1177/1533317508327587] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
Alzheimer's disease is characterized by degeneration and dysfunction of synapses and neurons in brain regions critical for learning and memory functions. The endogenous generation of new neurons in certain regions of the mature brain, derived from primitive cells termed neural stem cells, has raised hope that neural stem cells may be recruited for structural brain repair. Stem cell therapy has been suggested as a possible strategy for replacing damaged circuitry and restoring learning and memory abilities in patients with Alzheimer's disease. In this review, we outline the promising investigations that are raising hope, and understanding the challenges behind translating underlying stem cell biology into novel clinical therapeutic potential in Alzheimer's disease.
Collapse
Affiliation(s)
- Zhongling Feng
- Bio Group, Nitto Denko Technical Corporation, Oceanside, California 92058, USA.
| | | | | |
Collapse
|