1
|
Diaz C, de la Torre MM, Rubenstein JLR, Puelles L. Dorsoventral Arrangement of Lateral Hypothalamus Populations in the Mouse Hypothalamus: a Prosomeric Genoarchitectonic Analysis. Mol Neurobiol 2023; 60:687-731. [PMID: 36357614 PMCID: PMC9849321 DOI: 10.1007/s12035-022-03043-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Accepted: 09/16/2022] [Indexed: 11/12/2022]
Abstract
The lateral hypothalamus (LH) has a heterogeneous cytoarchitectonic organization that has not been elucidated in detail. In this work, we analyzed within the framework of the prosomeric model the differential expression pattern of 59 molecular markers along the ventrodorsal dimension of the medial forebrain bundle in the mouse, considering basal and alar plate subregions of the LH. We found five basal (LH1-LH5) and four alar (LH6-LH9) molecularly distinct sectors of the LH with neuronal cell groups that correlate in topography with previously postulated alar and basal hypothalamic progenitor domains. Most peptidergic populations were restricted to one of these LH sectors though some may have dispersed into a neighboring sector. For instance, histaminergic Hdc-positive neurons were mostly contained within the basal LH3, Nts (neurotensin)- and Tac2 (tachykinin 2)-expressing cells lie strictly within LH4, Hcrt (hypocretin/orexin)-positive and Pmch (pro-melanin-concentrating hormone)-positive neurons appeared within separate LH5 subdivisions, Pnoc (prepronociceptin)-expressing cells were mainly restricted to LH6, and Sst (somatostatin)-positive cells were identified within the LH7 sector. The alar LH9 sector, a component of the Foxg1-positive telencephalo-opto-hypothalamic border region, selectively contained Satb2-expressing cells. Published studies of rodent LH subdivisions have not described the observed pattern. Our genoarchitectonic map should aid in systematic approaches to elucidate LH connectivity and function.
Collapse
Affiliation(s)
- Carmen Diaz
- Department of Medical Sciences, School of Medicine and Institute for Research in Neurological Disabilities, University of Castilla-La Mancha, 02006 Albacete, Spain
| | - Margaret Martinez de la Torre
- Department of Human Anatomy and Psychobiology and IMIB-Arrixaca Institute, University of Murcia, 30100 Murcia, Spain
| | - John L. R. Rubenstein
- Nina Ireland Laboratory of Developmental Neurobiology, Department of Psychiatry, UCSF Medical School, San Francisco, California USA
| | - Luis Puelles
- Department of Human Anatomy and Psychobiology and IMIB-Arrixaca Institute, University of Murcia, 30100 Murcia, Spain
| |
Collapse
|
2
|
Bokulić E, Medenica T, Knezović V, Štajduhar A, Almahariq F, Baković M, Judaš M, Sedmak G. The Stereological Analysis and Spatial Distribution of Neurons in the Human Subthalamic Nucleus. Front Neuroanat 2022; 15:749390. [PMID: 34970124 PMCID: PMC8712451 DOI: 10.3389/fnana.2021.749390] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Accepted: 11/17/2021] [Indexed: 11/13/2022] Open
Abstract
The subthalamic nucleus (STN) is a small, ovoid structure, and an important site of deep brain stimulation (DBS) for the treatment of Parkinson’s disease. Although the STN is a clinically important structure, there are many unresolved issues with regard to it. These issues are especially related to the anatomical subdivision, neuronal phenotype, neuronal composition, and spatial distribution. In this study, we have examined the expression pattern of 8 neuronal markers [nNOS, NeuN, parvalbumin (PV), calbindin (CB), calretinin (CR), FOXP2, NKX2.1, and PAX6] in the adult human STN. All of the examined markers, except CB, were present in the STN. To determine the neuronal density, we have performed stereological analysis on Nissl-stained and immunohistochemical slides of positive markers. The stereology data were also used to develop a three-dimensional map of the spatial distribution of neurons within the STN. The nNOS population exhibited the largest neuronal density. The estimated total number of nNOS STN neurons is 281,308 ± 38,967 (± 13.85%). The STN neuronal subpopulations can be divided into two groups: one with a neuronal density of approximately 3,300 neurons/mm3 and the other with a neuronal density of approximately 2,200 neurons/mm3. The largest density of STN neurons was observed along the ventromedial border of the STN and the density gradually decreased toward the dorsolateral border. In this study, we have demonstrated the presence of 7 neuronal markers in the STN, three of which were not previously described in the human STN. The human STN is a collection of diverse, intermixed neuronal subpopulations, and our data, as far as the cytoarchitectonics is concerned, did not support the tripartite STN subdivision.
Collapse
Affiliation(s)
- Ema Bokulić
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia
| | - Tila Medenica
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia
| | - Vinka Knezović
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia
| | - Andrija Štajduhar
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia.,School of Public Health "Andrija Štampar," University of Zagreb School of Medicine, Zagreb, Croatia
| | - Fadi Almahariq
- Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia.,Department of Neurosurgery, Clinical Hospital "Dubrava," Zagreb, Croatia
| | - Marija Baković
- Department of Forensic Medicine, University of Zagreb School of Medicine, Zagreb, Croatia
| | - Miloš Judaš
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia
| | - Goran Sedmak
- Croatian Institute for Brain Research, University of Zagreb School of Medicine, Zagreb, Croatia.,Centre of Excellence for Basic, Clinical and Translational Neuroscience, Zagreb, Croatia
| |
Collapse
|
3
|
López-González L, Alonso A, García-Calero E, de Puelles E, Puelles L. Tangential Intrahypothalamic Migration of the Mouse Ventral Premamillary Nucleus and Fgf8 Signaling. Front Cell Dev Biol 2021; 9:676121. [PMID: 34095148 PMCID: PMC8170039 DOI: 10.3389/fcell.2021.676121] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 04/15/2021] [Indexed: 02/02/2023] Open
Abstract
The tuberal hypothalamic ventral premamillary nucleus (VPM) described in mammals links olfactory and metabolic cues with mating behavior and is involved in the onset of puberty. We offer here descriptive and experimental evidence on a migratory phase in the development of this structure in mice at E12.5–E13.5. Its cells originate at the retromamillary area (RM) and then migrate tangentially rostralward, eschewing the mamillary body, and crossing the molecularly distinct perimamillary band, until they reach a definitive relatively superficial ventral tuberal location. Corroborating recent transcriptomic studies reporting a variety of adult glutamatergic cell types in the VPM, and different projections in the adult, we found that part of this population heterogeneity emerges already early in development, during tangential migration, in the form of differential gene expression properties of at least 2–3 mixed populations possibly derived from subtly different parts of the RM. These partly distribute differentially in the core and shell parts of the final VPM. Since there is a neighboring acroterminal source of Fgf8, and Fgfr2 is expressed at the early RM, we evaluated a possible influence of Fgf8 signal on VPM development using hypomorphic Fgf8neo/null embryos. These results suggested a trophic role of Fgf8 on RM and all cells migrating tangentially out of this area (VPM and the subthalamic nucleus), leading in hypomorphs to reduced cellularity after E15.5 without alteration of the migrations proper.
Collapse
Affiliation(s)
- Lara López-González
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain.,Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain
| | - Antonia Alonso
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain.,Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain
| | - Elena García-Calero
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain.,Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain
| | - Eduardo de Puelles
- Instituto de Neurociencias de Alicante, CSIC, Universidad Miguel Hernández, Alicante, Spain
| | - Luis Puelles
- Department of Human Anatomy and Psychobiology, School of Medicine, University of Murcia, Murcia, Spain.,Biomedical Research Institute of Murcia (IMIB-Arrixaca), Murcia, Spain
| |
Collapse
|
4
|
Mickelsen LE, Flynn WF, Springer K, Wilson L, Beltrami EJ, Bolisetty M, Robson P, Jackson AC. Cellular taxonomy and spatial organization of the murine ventral posterior hypothalamus. eLife 2020; 9:58901. [PMID: 33119507 PMCID: PMC7595735 DOI: 10.7554/elife.58901] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 09/21/2020] [Indexed: 01/02/2023] Open
Abstract
The ventral posterior hypothalamus (VPH) is an anatomically complex brain region implicated in arousal, reproduction, energy balance, and memory processing. However, neuronal cell type diversity within the VPH is poorly understood, an impediment to deconstructing the roles of distinct VPH circuits in physiology and behavior. To address this question, we employed a droplet-based single-cell RNA sequencing (scRNA-seq) approach to systematically classify molecularly distinct cell populations in the mouse VPH. Analysis of >16,000 single cells revealed 20 neuronal and 18 non-neuronal cell populations, defined by suites of discriminatory markers. We validated differentially expressed genes in selected neuronal populations through fluorescence in situ hybridization (FISH). Focusing on the mammillary bodies (MB), we discovered transcriptionally-distinct clusters that exhibit neuroanatomical parcellation within MB subdivisions and topographic projections to the thalamus. This single-cell transcriptomic atlas of VPH cell types provides a resource for interrogating the circuit-level mechanisms underlying the diverse functions of VPH circuits.
Collapse
Affiliation(s)
- Laura E Mickelsen
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, United States.,Connecticut Institute for the Brain and Cognitive Sciences, Storrs, United States
| | - William F Flynn
- The Jackson Laboratory for Genomic Medicine, Farmington, United States
| | - Kristen Springer
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, United States
| | - Lydia Wilson
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, United States
| | - Eric J Beltrami
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, United States
| | - Mohan Bolisetty
- The Jackson Laboratory for Genomic Medicine, Farmington, United States
| | - Paul Robson
- The Jackson Laboratory for Genomic Medicine, Farmington, United States.,Department of Genetics and Genome Sciences, University of Connecticut Health Center, Farmington, United States.,Institute for Systems Genomics, University of Connecticut, Farmington, United States
| | - Alexander C Jackson
- Department of Physiology and Neurobiology, University of Connecticut, Storrs, United States.,Connecticut Institute for the Brain and Cognitive Sciences, Storrs, United States.,Institute for Systems Genomics, University of Connecticut, Farmington, United States
| |
Collapse
|
5
|
Rozani I, Tsapara G, Witts EC, Deaville SJ, Miles GB, Zagoraiou L. Pitx2 cholinergic interneurons are the source of C bouton synapses on brainstem motor neurons. Sci Rep 2019; 9:4936. [PMID: 30894556 PMCID: PMC6426951 DOI: 10.1038/s41598-019-39996-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 01/15/2019] [Indexed: 11/29/2022] Open
Abstract
Cholinergic neuromodulation has been described throughout the brain and has been implicated in various functions including attention, food intake and response to stress. Cholinergic modulation is also thought to be important for regulating motor systems, as revealed by studies of large cholinergic synapses on spinal motor neurons, called C boutons, which seem to control motor neuron excitability in a task-dependent manner. C boutons on spinal motor neurons stem from spinal interneurons that express the transcription factor Pitx2. C boutons have also been identified on the motor neurons of specific cranial nuclei. However, the source and roles of cranial C boutons are less clear. Previous studies suggest that they originate from Pitx2+ and Pitx2- neurons, in contrast to spinal cord C boutons that originate solely from Pitx2 neurons. Here, we address this controversy using mouse genetics, and demonstrate that brainstem C boutons are Pitx2+ derived. We also identify new Pitx2 populations and map the cholinergic Pitx2 neurons of the mouse brain. Taken together, our data present important new information about the anatomical organization of cholinergic systems which impact motor systems of the brainstem. These findings will enable further analyses of the specific roles of cholinergic modulation in motor control.
Collapse
Affiliation(s)
- Ismini Rozani
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou Str., 11527, Athens, Greece
- Division of Animal and Human Physiology, Department of Biology, National & Kapodistrian University of Athens, Panepistimiopolis, Ilisia, Greece
| | - Georgia Tsapara
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou Str., 11527, Athens, Greece
- Institute of Molecular Life Sciences, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
| | - Emily C Witts
- Sainsbury Wellcome Centre, 25 Howland Street, London, W1T 4JG, UK
- School of Psychology & Neuroscience, University of St Andrews, Fife, KY169JP, UK
| | - S James Deaville
- School of Psychology & Neuroscience, University of St Andrews, Fife, KY169JP, UK
| | - Gareth B Miles
- School of Psychology & Neuroscience, University of St Andrews, Fife, KY169JP, UK
| | - Laskaro Zagoraiou
- Center of Basic Research, Biomedical Research Foundation of the Academy of Athens, 4 Soranou Ephessiou Str., 11527, Athens, Greece.
| |
Collapse
|
6
|
Yao H, Hill SF, Skidmore JM, Sperry ED, Swiderski DL, Sanchez GJ, Bartels CF, Raphael Y, Scacheri PC, Iwase S, Martin DM. CHD7 represses the retinoic acid synthesis enzyme ALDH1A3 during inner ear development. JCI Insight 2018; 3:97440. [PMID: 29467333 DOI: 10.1172/jci.insight.97440] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 01/23/2018] [Indexed: 12/13/2022] Open
Abstract
CHD7, an ATP-dependent chromatin remodeler, is disrupted in CHARGE syndrome, an autosomal dominant disorder characterized by variably penetrant abnormalities in craniofacial, cardiac, and nervous system tissues. The inner ear is uniquely sensitive to CHD7 levels and is the most commonly affected organ in individuals with CHARGE. Interestingly, upregulation or downregulation of retinoic acid (RA) signaling during embryogenesis also leads to developmental defects similar to those in CHARGE syndrome, suggesting that CHD7 and RA may have common target genes or signaling pathways. Here, we tested three separate potential mechanisms for CHD7 and RA interaction: (a) direct binding of CHD7 with RA receptors, (b) regulation of CHD7 levels by RA, and (c) CHD7 binding and regulation of RA-related genes. We show that CHD7 directly regulates expression of Aldh1a3, the gene encoding the RA synthetic enzyme ALDH1A3 and that loss of Aldh1a3 partially rescues Chd7 mutant mouse inner ear defects. Together, these studies indicate that ALDH1A3 acts with CHD7 in a common genetic pathway to regulate inner ear development, providing insights into how CHD7 and RA regulate gene expression and morphogenesis in the developing embryo.
Collapse
Affiliation(s)
- Hui Yao
- Department of Pediatrics and Communicable Diseases
| | | | | | - Ethan D Sperry
- Department of Human Genetics.,Medical Scientist Training Program, and
| | - Donald L Swiderski
- Department of Otolaryngology, University of Michigan, Ann Arbor, Michigan, USA
| | | | - Cynthia F Bartels
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio, USA
| | - Yehoash Raphael
- Department of Otolaryngology, University of Michigan, Ann Arbor, Michigan, USA
| | - Peter C Scacheri
- Department of Genetics, Case Western Reserve University, Cleveland, Ohio, USA
| | | | - Donna M Martin
- Department of Pediatrics and Communicable Diseases.,Department of Human Genetics.,Medical Scientist Training Program, and
| |
Collapse
|
7
|
Sasaki K, Othman MB, Demura M, Watanabe M, Isoda H. Modulation of Neurogenesis through the Promotion of Energy Production Activity Is behind the Antidepressant-Like Effect of Colonial Green Alga, Botryococcus braunii. Front Physiol 2017; 8:900. [PMID: 29176952 PMCID: PMC5686089 DOI: 10.3389/fphys.2017.00900] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Accepted: 10/24/2017] [Indexed: 12/31/2022] Open
Abstract
Algae have been recognized as important resources providing functional components due to their capacity to exert beneficial effects on health. Therefore, there is increasing interest in investigating the biological activity of algae. In this study, we evaluated the antidepressant-like effect of the administration of 100 mg/kg/day of the ethanol extract of colonial green alga Botryococcus braunii (EEB) for 14 consecutive days in the forced swimming test (FST)-induced depression in imprinting control region (ICR) mice. Imipramine, a commercial antidepressant drug, was used as a positive control. In addition, we investigated the molecular mechanisms underlying the effect of EEB by measuring ATP production and by assessing any change in gene expression at the end of the treatment using real-time polymerase chain reaction (PCR) and microarray assays. We showed that the immobility time in the water-administered control (FST stress) group gradually increased from day 1 to day 14. However, treatment with EEB caused a significant decrease of immobility time in the FST compared with that in the FST stress group. Microarray and real-time PCR results revealed that EEB treatment induced variation in the expression of several genes associated with neurogenesis, energy metabolism, and dopamine synthesis. Interestingly, we revealed that only EEB treatment enhanced the promotion of energy production, while treatment with imipramine was ineffective. Our study provides the first evidence that B. braunii enhances energy production, which may contribute to the modulation of neurogenesis and to the enhancement of dopaminergic function, in turn potentially underlying the antistress- and antidepressant-like effects that we observed.
Collapse
Affiliation(s)
- Kazunori Sasaki
- Interdisciplinary Research Center for Catalytic Chemistry, National Institute of Advanced Industrial Science and Technology, Tsukuba, Japan.,Faculty of Pure and Applied Sciences, University of Tsukuba, Tsukuba, Japan
| | - Mahmoud B Othman
- Alliance for Research on North Africa, University of Tsukuba, Tsukuba, Japan
| | - Mikihide Demura
- Algal Biomass and Energy System R&D Center, University of Tsukuba, Tsukuba, Japan
| | - Makoto Watanabe
- Algal Biomass and Energy System R&D Center, University of Tsukuba, Tsukuba, Japan.,Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Hiroko Isoda
- Alliance for Research on North Africa, University of Tsukuba, Tsukuba, Japan.,Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| |
Collapse
|
8
|
Foxa1 is essential for development and functional integrity of the subthalamic nucleus. Sci Rep 2016; 6:38611. [PMID: 27934886 PMCID: PMC5146925 DOI: 10.1038/srep38611] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Accepted: 11/10/2016] [Indexed: 01/15/2023] Open
Abstract
Inactivation of transcription factor Foxa1 in mice results in neonatal mortality of unknown cause. Here, we report that ablation of Foxa1 causes impaired development and loss of the subthalamic nucleus (STN). Functional deficits in the STN have been implicated in the etiology of Huntington's and Parkinson's disease. We show that neuronal ablation by Synapsin1-Cre-mediated Foxa1 deletion is sufficient to induce hyperlocomotion in mice. Transcriptome profiling of STN neurons in conditional Foxa1 knockout mice revealed changes in gene expression reminiscent of those in neurodegenerative diseases. We identified Ppargc1a, a transcriptional co-activator that is implicated in neurodegeneration, as a Foxa1 target. These findings were substantiated by the observation of Foxa1-dependent demise of STN neurons in conditional models of Foxa1 mutant mice. Finally, we show that the spontaneous firing activity of Foxa1-deficient STN neurons is profoundly impaired. Our data reveal so far elusive roles of Foxa1 in the development and maintenance of STN function.
Collapse
|
9
|
Chen L, Martino V, Dombkowski A, Williams T, West-Mays J, Gage PJ. AP-2β Is a Downstream Effector of PITX2 Required to Specify Endothelium and Establish Angiogenic Privilege During Corneal Development. Invest Ophthalmol Vis Sci 2016; 57:1072-81. [PMID: 26968737 PMCID: PMC4790471 DOI: 10.1167/iovs.15-18103] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2015] [Accepted: 02/03/2016] [Indexed: 12/24/2022] Open
Abstract
PURPOSE The homeodomain transcription factor, PITX2, is at the apex of a genetic pathway required for corneal development, but the critical effector genes regulated by the PITX2 remain unknown. The purpose of this study was to discover and validate PITX2-dependent mechanisms required for specifying cell lineages and establishing angiogenic privilege within the developing cornea. METHODS Microarrays were used to compare gene expression in corneas isolated from temporal Pitx2 knockout embryos and control littermates. Quantitative RT-PCR and immunohistochemistry was used to further validate Tfap2b expression differences in Pitx2 knockout versus control corneas. In situ hybridization and protein immunohistochemistry were used to assay eyes of a Tfap2b allelic series of embryos to identify differentiated cellular lineages in the cornea, blood vessel endothelium, or lymphatic vessel endothelium. RESULTS We show that PITX2 is required for the expression of Tfap2b, encoding the AP-2β transcription factor, in the neural crest during corneal development. Markers of differentiated corneal epithelium and stroma are expressed in the absence of AP-2β. In contrast, markers of differentiated corneal endothelium are not expressed in the absence of AP-2β. Endomucin+ blood vessels are present throughout the developing corneal stroma in the absence of AP-2β, whereas LYVE1+ lymphatic vessels are not found. CONCLUSIONS The AP-2β transcription factor is an important effector of PITX2 function during corneal development, required for differentiation of corneal endothelium and establishment of angiogenic privilege. Unlike PITX2, AP-2β is not required for the early expression of available lineage specific markers for the corneal epithelium and stroma during embryogenesis, nor establishment of lymphangiogenic privilege. Therefore, additional PITX2-dependent factors likely regulate these latter processes during embryonic development. These results extend our understanding of the genetic mechanisms regulating cornea development.
Collapse
Affiliation(s)
- Lisheng Chen
- Department of Ophthalmology & Visual Sciences, University of Michigan, Ann Arbor, Michigan, United States
| | - Vanessa Martino
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Alan Dombkowski
- Department of Pediatrics, Wayne State University, Detroit, Michigan, United States
| | - Trevor Williams
- Department of Craniofacial Biology and Department of Cell and Developmental Biology, University of Colorado–Denver, Denver, Colorado, United States
| | - Judith West-Mays
- Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada
| | - Philip J. Gage
- Department of Ophthalmology & Visual Sciences, University of Michigan, Ann Arbor, Michigan, United States
- Department of Cell & Developmental Biology, University of Michigan, Ann Arbor, Michigan, United States
| |
Collapse
|
10
|
Klafke R, Prem Anand AA, Wurst W, Prakash N, Wizenmann A. Differences in the spatiotemporal expression and epistatic gene regulation of the mesodiencephalic dopaminergic precursor marker PITX3 during chicken and mouse development. Development 2016; 143:691-702. [DOI: 10.1242/dev.126748] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2015] [Accepted: 01/05/2016] [Indexed: 11/20/2022]
Abstract
Mesodiencephalic dopaminergic (mdDA) neurons are located in the ventral mesencephalon and caudal diencephalon of all tetrapod species studied so far. They are the most prominent DA neuronal population and are implicated in control and modulation of motor, cognitive and rewarding/affective behaviors. Their degeneration or dysfunction is intimately linked to several neurological and neuropsychiatric human diseases. To gain further insights into their generation, we studied spatiotemporal expression patterns and epistatic interactions in chick embryos of selected marker genes and signaling pathways associated with mdDA neuron development in mouse. We detected striking differences in the expression patterns of the chick orthologs of the mouse mdDA marker genes Pitx3 and Aldh1a1, which suggests important differences between the species in the generation/generating of these cells. We also discovered that the Sonic hedgehog signaling pathway is both, necessary and sufficient for the induction of ectopic PITX3 expression in chick mesencephalon downstream of WNT9A induced LMX1a transcription. These aspects of early chicken development resemble the ontogeny of zebrafish diencephalic DA neuronal populations, and suggest a divergence between birds and mammals during evolution.
Collapse
Affiliation(s)
- Ruth Klafke
- Institute of Developmental Genetics, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - A. Alwin Prem Anand
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Oesterbergstrasse 3, 72074 Tuebingen, Germany
| | - Wolfgang Wurst
- Institute of Developmental Genetics, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
- Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik c/o Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE) Standort München, Schillerstr. 44, 80336 München, Germany
- Munich Cluster for Systems Neurology (SyNergy), Adolf-Butenandt-Institut, Ludwig-Maximilians-Universität München, Schillerstrasse 44, 80336 München, Germany
| | - Nilima Prakash
- Institute of Developmental Genetics, Helmholtz Zentrum München, Deutsches Forschungszentrum für Gesundheit und Umwelt (GmbH), Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
- Technische Universität München-Weihenstephan, Lehrstuhl für Entwicklungsgenetik c/o Helmholtz Zentrum München, Ingolstädter Landstr. 1, 85764 Neuherberg, Germany
| | - Andrea Wizenmann
- Institute of Clinical Anatomy and Cell Analysis, University of Tübingen, Oesterbergstrasse 3, 72074 Tuebingen, Germany
| |
Collapse
|
11
|
Baronchelli S, La Spada A, Conforti P, Redaelli S, Dalprà L, De Blasio P, Cattaneo E, Biunno I. Investigating DNA Methylation Dynamics and Safety of Human Embryonic Stem Cell Differentiation Toward Striatal Neurons. Stem Cells Dev 2015; 24:2366-77. [DOI: 10.1089/scd.2015.0057] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- Simona Baronchelli
- Institute of Genetic and Biomedical Research, National Research Council (UOS IRGB-CNR), Milan, Italy
| | - Alberto La Spada
- Institute of Genetic and Biomedical Research, National Research Council (UOS IRGB-CNR), Milan, Italy
| | - Paola Conforti
- Department of Biosciences, Center for Stem Cell Research, University of Milan, Milan, Italy
| | - Serena Redaelli
- Department of Surgery and Translational Medicine, University of Milan-Bicocca, Monza, Italy
| | - Leda Dalprà
- Department of Surgery and Translational Medicine, University of Milan-Bicocca, Monza, Italy
| | | | - Elena Cattaneo
- Department of Biosciences, Center for Stem Cell Research, University of Milan, Milan, Italy
| | - Ida Biunno
- Institute of Genetic and Biomedical Research, National Research Council (UOS IRGB-CNR), Milan, Italy
- IRCCS Multimedica, Milan, Italy
| |
Collapse
|
12
|
The pattern of congenital heart defects arising from reduced Tbx5 expression is altered in a Down syndrome mouse model. BMC DEVELOPMENTAL BIOLOGY 2015. [PMID: 26208718 PMCID: PMC4514943 DOI: 10.1186/s12861-015-0080-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Nearly half of all individuals with Down Syndrome (DS) have some type of congenital heart defect (CHD), suggesting that DS sensitizes to CHD but does not cause it. We used a common mouse model of DS, the Ts65Dn mouse, to study the contribution of Tbx5, a known modifier of CHD, to heart defects on a trisomic backgroun. Mice that were heterozygous for a Tbx5 null allele were crossed with Ts65Dn mice. Thoraxes of progeny were fixed in 10% formalin, embedded in paraffin, and sectioned for analysis of CHD. Gene expression in embryonic hearts was examined by quantitative PCR and in situ hybridization. A TBX5 DNA binding site was verified by luciferase assays. METHODS Mice that were heterozygous for a Tbx5 null allele were crossed with Ts65Dn mice. Thoraxes of progeny were fixed in 10% formalin, embedded in paraffin, and sectioned for analysis of CHD. Gene expression in embryonic hearts was examined by quantitative PCR and in situ hybridization. A TBX5 DNA binding site was verified by luciferase assays. RESULTS We crossed mice that were heterozygous for a Tbx5 null allele with Ts65Dn mice. Mice that were trisomic and carried the Tbx5 mutation (Ts65Dn;Tbx5 (+/-) ) had a significantly increased incidence of overriding aorta compared to their euploid littermates. Ts65Dn;Tbx5 (+/-) mice also showed reduced expression of Pitx2, a molecular marker for the left atrium. Transcript levels of the trisomic Adamts1 gene were decreased in Tbx5 (+/-) mice compared to their euploid littermates. Evidence of a valid binding site for TBX5 upstream of the trisomic Adamts1 locus was also shown. CONCLUSION Haploinsufficiency of Tbx5 and trisomy affects alignment of the aorta and this effect may stem from deviations from normal left-right patterning in the heart. We have unveiled a previously unknown interaction between the Tbx5 gene and trisomy, suggesting a connection between Tbx5 and trisomic genes important during heart development.
Collapse
|
13
|
Gergics P, Brinkmeier ML, Camper SA. Lhx4 deficiency: increased cyclin-dependent kinase inhibitor expression and pituitary hypoplasia. Mol Endocrinol 2015; 29:597-612. [PMID: 25668206 PMCID: PMC4399274 DOI: 10.1210/me.2014-1380] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Accepted: 02/06/2015] [Indexed: 12/30/2022] Open
Abstract
Defects in the Lhx4, Lhx3, and Pitx2 genes can cause combined pituitary hormone deficiency and pituitary hypoplasia in both humans and mice. Not much is known about the mechanism underlying hypoplasia in these mutants beyond generally increased cell death and poorly maintained proliferation. We identified both common and unique abnormalities in developmental regulation of key cell cycle regulator gene expression in each of these three mutants. All three mutants exhibit reduced expression of the proliferative marker Ki67 and the transitional marker p57. We discovered that expression of the cyclin-dependent kinase inhibitor 1a (Cdkn1a or p21) is expanded dorsally in the pituitary primordium of both Lhx3 and Lhx4 mutants. Uniquely, Lhx4 mutants exhibit reduced cyclin D1 expression and have auxiliary pouch-like structures. We show evidence for indirect and direct effects of LHX4 on p21 expression in αT3-1 pituitary cells. In summary, Lhx4 is necessary for efficient pituitary progenitor cell proliferation and restriction of p21 expression.
Collapse
Affiliation(s)
- Peter Gergics
- Department of Human Genetics, University of Michigan, Ann Arbor, Michigan 48109
| | | | | |
Collapse
|
14
|
Waite MR, Martin DM. Axial level-specific regulation of neuronal development: lessons from PITX2. J Neurosci Res 2015; 93:195-8. [PMID: 25124216 DOI: 10.1002/jnr.23471] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 06/09/2014] [Accepted: 07/16/2014] [Indexed: 12/19/2022]
Abstract
Transcriptional regulation of gene expression is vital for proper control of proliferation, migration, differentiation, and survival of developing neurons. Pitx2 encodes a homeodomain transcription factor that is highly expressed in the developing and adult mammalian brain. In humans, mutations in PITX2 result in Rieger syndrome, characterized by defects in the development of the eyes, umbilicus, and teeth and variable abnormalities in the brain, including hydrocephalus and cerebellar hypoplasia. Alternative splicing of Pitx2 in the mouse results in three isoforms, Pitx2a, Pitx2b, and Pitx2c, each of which is expressed symmetrically along the left-right axis of the brain throughout development. Here, we review recent evidence for axial and brain region-specific requirements for Pitx2 during neuronal migration and differentiation, highlighting known isoform contributions.
Collapse
Affiliation(s)
- Mindy R Waite
- Cellular and Molecular Biology Graduate Program, University of Michigan, Ann Arbor, Michigan
| | | |
Collapse
|
15
|
Gage PJ, Kuang C, Zacharias AL. The homeodomain transcription factor PITX2 is required for specifying correct cell fates and establishing angiogenic privilege in the developing cornea. Dev Dyn 2014; 243:1391-400. [PMID: 25044936 PMCID: PMC4206698 DOI: 10.1002/dvdy.24165] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2014] [Revised: 06/30/2014] [Accepted: 07/10/2014] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND Correct specification of cell lineages and establishing angiogenic privilege within the developing cornea are essential for normal vision but the mechanisms controlling these processes are poorly understood. RESULTS We show that the homeodomain transcription factor PItX2 is expressed in mesenchymal cells of the developing and mature cornea and use a temporal gene knockout approach to demonstrate that PITX2 is required for corneal morphogenesis and the specification of cell fates within the surface ectoderm and mesenchymal primordia. PITX2 is also required to establish angiogenic privilege in the developing cornea. Further, the expression of Dkk2 and suppression of canonical Wnt signaling activity levels are key mechanisms by which PITX2 specifies ocular surface ectoderm as cornea. In contrast, specifying the underlying mesenchyme to corneal fates and establishing angiogenic privilege in the cornea are less sensitive to DKK2 activity. Finally, the cellular expression patterns of FOXC2, PITX1, and BARX2 in Pitx2 and Dkk2 mutants suggest that these transcription factors may be involved in specifying cell fate and establishing angiogenic privilege within the corneal mesenchyme. However, they are unlikely to play a role in specifying cell fate within the corneal ectoderm. CONCLUSIONS Together, these data provide important insights into the mechanisms regulating cornea development.
Collapse
Affiliation(s)
- Philip J. Gage
- Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Chen Kuang
- Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Amanda L. Zacharias
- Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| |
Collapse
|
16
|
Nawaz I, Qiu X, Wu H, Li Y, Fan Y, Hu LF, Zhou Q, Ernberg I. Development of a multiplex methylation specific PCR suitable for (early) detection of non-small cell lung cancer. Epigenetics 2014; 9:1138-48. [PMID: 24937636 DOI: 10.4161/epi.29499] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Lung cancer is a worldwide health problem and a leading cause of cancer-related deaths. Silencing of potential tumor suppressor genes (TSGs) by aberrant promoter methylation is an early event in the initiation and development of cancer. Thus, methylated cancer type-specific TSGs in DNA can serve as useful biomarkers for early cancer detection. We have now developed a "Multiplex Methylation Specific PCR" (MMSP) assay for analysis of the methylation status of multiple potential TSGs by a single PCR reaction. This method will be useful for early diagnosis and treatment outcome studies of non-small cell lung cancer (NSCLC). Genome-wide CpG methylation and expression microarrays were performed on lung cancer tissues and matched distant non-cancerous tissues from three NSCLC patients from China. Thirty-eight potential TSGs were selected and analyzed by methylation PCR on bisulfite treated DNA. On the basis of sensitivity and specificity, six marker genes, HOXA9, TBX5, PITX2, CALCA, RASSF1A, and DLEC1, were selected to establish the MMSP assay. This assay was then used to analyze lung cancer tissues and matched distant non-cancerous tissues from 70 patients with NSCLC, as well as 24 patients with benign pulmonary lesion as controls. The sensitivity of the assay was 99% (69/70). HOXA9 and TBX5 were the 2 most sensitive marker genes: 87% (61/70) and 84% (59/70), respectively. RASSF1A and DLEC1 showed the highest specificity at 99% (69/70). Using the criterion of identifying at least any two methylated marker genes, 61/70 cancer samples were positive, corresponding to a sensitivity of 87% and a specificity of 94%. Early stage I or II NSCLC could even be detected with a 100% specificity and 86% sensitivity. In conclusion, MMSP has the potential to be developed into a population-based screening tool and can be useful for early diagnosis of NSCLC. It might also be suitable for monitoring treatment outcome and recurrence.
Collapse
Affiliation(s)
- Imran Nawaz
- Department of Microbiology; Tumor and Cell Biology; Karolinska Institute; Stockholm, Sweden; Department of Microbiology; Faculty of Life Sciences; University of Balochistan; Quetta, Pakistan
| | - Xiaoming Qiu
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment; Tianjin Lung Cancer Institute; Tianjin Medical University General Hospital; Tianjin, PR China
| | - Heng Wu
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment; Tianjin Lung Cancer Institute; Tianjin Medical University General Hospital; Tianjin, PR China
| | - Yang Li
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment; Tianjin Lung Cancer Institute; Tianjin Medical University General Hospital; Tianjin, PR China
| | - Yaguang Fan
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment; Tianjin Lung Cancer Institute; Tianjin Medical University General Hospital; Tianjin, PR China
| | - Li-Fu Hu
- Department of Microbiology; Tumor and Cell Biology; Karolinska Institute; Stockholm, Sweden
| | - Qinghua Zhou
- Tianjin Key Laboratory of Lung Cancer Metastasis and Tumor Microenvironment; Tianjin Lung Cancer Institute; Tianjin Medical University General Hospital; Tianjin, PR China
| | - Ingemar Ernberg
- Department of Microbiology; Tumor and Cell Biology; Karolinska Institute; Stockholm, Sweden
| |
Collapse
|
17
|
Barratt KS, Glanville-Jones HC, Arkell RM. The Zic2
gene directs the formation and function of node cilia to control cardiac situs. Genesis 2014; 52:626-35. [DOI: 10.1002/dvg.22767] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2013] [Revised: 02/13/2014] [Accepted: 02/25/2014] [Indexed: 01/10/2023]
Affiliation(s)
- Kristen S. Barratt
- Early Mammalian Development Laboratory; Research School of Biology, Evolution, Ecology and Genetics, The Australian National University; Canberra ACT 0200 Australia
| | - Hannah C. Glanville-Jones
- Early Mammalian Development Laboratory; Research School of Biology, Evolution, Ecology and Genetics, The Australian National University; Canberra ACT 0200 Australia
| | - Ruth M. Arkell
- Early Mammalian Development Laboratory; Research School of Biology, Evolution, Ecology and Genetics, The Australian National University; Canberra ACT 0200 Australia
| |
Collapse
|
18
|
Alwin Prem Anand A, Gowri Sankar S, Kokila Vani V. Immortalization of neuronal progenitors using SV40 large T antigen and differentiation towards dopaminergic neurons. J Cell Mol Med 2014; 16:2592-610. [PMID: 22863662 PMCID: PMC4118228 DOI: 10.1111/j.1582-4934.2012.01607.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Transplantation is common in clinical practice where there is availability of the tissue and organ. In the case of neurodegenerative disease such as Parkinson's disease (PD), transplantation is not possible as a result of the non-availability of tissue or organ and therefore, cell therapy is an innovation in clinical practice. However, the availability of neuronal cells for transplantation is very limited. Alternatively, immortalized neuronal progenitors could be used in treating PD. The neuronal progenitor cells can be differentiated into dopaminergic phenotype. Here in this article, the current understanding of the molecular mechanisms involved in the differentiation of dopaminergic phenotype from the neuronal progenitors immortalized with SV40 LT antigen is discussed. In addition, the methods of generating dopaminergic neurons from progenitor cells and the factors that govern their differentiation are elaborated. Recent advances in cell-therapy based transplantation in PD patients and future prospects are discussed.
Collapse
|
19
|
Matsui T, Hongo Y, Haizuka Y, Kaida K, Matsumura G, Martin DM, Kobayashi Y. C-terminals in the mouse branchiomotor nuclei originate from the magnocellular reticular formation. Neurosci Lett 2013; 548:137-42. [PMID: 23756176 PMCID: PMC3776024 DOI: 10.1016/j.neulet.2013.05.063] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2013] [Revised: 05/13/2013] [Accepted: 05/31/2013] [Indexed: 10/26/2022]
Abstract
Large cholinergic synaptic boutons called "C-terminals" contact motoneurons and regulate their excitability. C-terminals in the spinal somatic motor nuclei originate from cholinergic interneurons in laminae VII and X that express a transcription factor Pitx2. Cranial motor nuclei contain another type of motoneuron: branchiomotor neurons. Although branchiomotor neurons receive abundant C-terminal projections, the neural source of these C-terminals remains unknown. In the present study, we first examined whether cholinergic neurons express Pitx2 in the reticular formation of the adult mouse brainstem, as in the spinal cord. Although Pitx2-positive cholinergic neurons were observed in the magnocellular reticular formation and region around the central canal in the caudal medulla, none was present more rostrally in the brainstem tegmentum. We next explored the origin of C-terminals in the branchiomotor nuclei by using biotinylated dextran amine (BDA). BDA injections into the magnocellular reticular formation of the medulla and pons resulted in the labeling of numerous C-terminals in the branchiomotor nuclei: the ambiguous, facial, and trigeminal motor nuclei. Our results revealed that the origins of C-terminals in the branchiomotor nuclei are cholinergic neurons in the magnocellular reticular formation not only in the caudal medulla, but also at more rostral levels of the brainstem, which lacks Pitx2-positive neurons.
Collapse
Affiliation(s)
- Toshiyasu Matsui
- Department of Anatomy and Neurobiology, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - Yu Hongo
- Department of Anatomy and Neurobiology, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
- Third Department of Internal Medicine, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - Yoshinori Haizuka
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan
| | - Kenichi Kaida
- Third Department of Internal Medicine, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| | - George Matsumura
- Department of Anatomy, Kyorin University School of Medicine, Mitaka, Tokyo 181-8611, Japan
| | - Donna M. Martin
- Departments of Pediatrics, Human Genetics, and the Cellular and Molecular Biology Program, The University of Michigan, Ann Arbor, MI 48019-5652, USA
| | - Yasushi Kobayashi
- Department of Anatomy and Neurobiology, National Defense Medical College, Tokorozawa, Saitama 359-8513, Japan
| |
Collapse
|
20
|
Waite MR, Skidmore JM, Micucci JA, Shiratori H, Hamada H, Martin JF, Martin DM. Pleiotropic and isoform-specific functions for Pitx2 in superior colliculus and hypothalamic neuronal development. Mol Cell Neurosci 2013; 52:128-39. [PMID: 23147109 PMCID: PMC3540135 DOI: 10.1016/j.mcn.2012.11.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 10/01/2012] [Accepted: 11/02/2012] [Indexed: 02/01/2023] Open
Abstract
Transcriptional regulation of gene expression during development is critical for proper neuronal differentiation and migration. Alternative splicing and differential isoform expression have been demonstrated for most mammalian genes, but their specific contributions to gene function are not well understood. In mice, the transcription factor gene Pitx2 is expressed as three different isoforms (PITX2A, PITX2B, and PITX2C) which have unique amino termini and common DNA binding homeodomains and carboxyl termini. The specific roles of these isoforms in neuronal development are not known. Here we report the onset of Pitx2ab and Pitx2c isoform-specific expression by E9.5 in the developing mouse brain. Using isoform-specific Pitx2 deletion mouse strains, we show that collicular neuron migration requires PITX2AB and that collicular GABAergic differentiation and targeting of hypothalamic projections require unique Pitx2 isoform dosage. These results provide insights into Pitx2 dosage and isoform-specific requirements underlying midbrain and hypothalamic development.
Collapse
Affiliation(s)
- Mindy R Waite
- Cellular and Molecular Biology Graduate Program, 2966 Taubman Medical Library, University of Michigan, Ann Arbor, MI 48109-0619, USA.
| | | | | | | | | | | | | |
Collapse
|
21
|
Delayed fusion and altered gene expression contribute to semicircular canal defects in Chd7 deficient mice. Mech Dev 2012; 129:308-23. [PMID: 22705977 DOI: 10.1016/j.mod.2012.06.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2012] [Revised: 05/30/2012] [Accepted: 06/07/2012] [Indexed: 11/20/2022]
Abstract
Proper morphogenesis of inner ear semicircular canals requires precise regulation of cellular proliferation, epithelial-to-mesenchymal transition, and fusion of epithelial plates. Epigenetic regulation of these processes is not well understood, but is likely to involve chromatin remodeling enzymes. CHD7 is a chromodomain-containing, ATP dependent helicase protein that is highly expressed in the developing ear and is required for semicircular canal development in both humans and mice. Here we report that mice with heterozygous loss of Chd7 function exhibit delayed semicircular canal genesis, delayed Netrin1 expression and disrupted expression of genes that are critical for semicircular canal formation (Bmp2, Bmp4, Msx1 and Fgf10). Complete loss of Chd7 results in aplasia of the semicircular canals and sensory vestibular organs, with reduced or absent expression of Otx1, Hmx3, Jagged1, Lmo4, Msx1 and Sox2. Our results suggest that Chd7 may have critical selector gene functions during inner ear morphogenesis. Detailed analysis of the epigenetic modifications underlying these gene expression changes should provide insights into semicircular canal development and help in the design of therapies for individuals with inner ear malformations.
Collapse
|
22
|
Fung FKC, Chan DW, Liu VWS, Leung THY, Cheung ANY, Ngan HYS. Increased expression of PITX2 transcription factor contributes to ovarian cancer progression. PLoS One 2012; 7:e37076. [PMID: 22615897 PMCID: PMC3352869 DOI: 10.1371/journal.pone.0037076] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2012] [Accepted: 04/13/2012] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Paired-like homeodomain 2 (PITX2) is a bicoid homeodomain transcription factor which plays an essential role in maintaining embryonic left-right asymmetry during vertebrate embryogenesis. However, emerging evidence suggests that the aberrant upregulation of PITX2 may be associated with tumor progression, yet the functional role that PITX2 plays in tumorigenesis remains unknown. PRINCIPAL FINDINGS Using real-time quantitative RT-PCR (Q-PCR), Western blot and immunohistochemical (IHC) analyses, we demonstrated that PITX2 was frequently overexpressed in ovarian cancer samples and cell lines. Clinicopathological correlation showed that the upregulated PITX2 was significantly associated with high-grade (P = 0.023) and clear cell subtype (P = 0.011) using Q-PCR and high-grade (P<0.001) ovarian cancer by IHC analysis. Functionally, enforced expression of PITX2 could promote ovarian cancer cell proliferation, anchorage-independent growth ability, migration/invasion and tumor growth in xenograft model mice. Moreover, enforced expression of PITX2 elevated the cell cycle regulatory proteins such as Cyclin-D1 and C-myc. Conversely, RNAi mediated knockdown of PITX2 in PITX2-high expressing ovarian cancer cells had the opposite effect. CONCLUSION Our findings suggest that the increased expression PITX2 is involved in ovarian cancer progression through promoting cell growth and cell migration/invasion. Thus, targeting PITX2 may serve as a potential therapeutic modality in the management of high-grade ovarian tumor.
Collapse
Affiliation(s)
- Frederic K. C. Fung
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - David W. Chan
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Vincent W. S. Liu
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Thomas H. Y. Leung
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Annie N. Y. Cheung
- Department of Pathology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| | - Hextan Y. S. Ngan
- Department of Obstetrics and Gynaecology, LKS Faculty of Medicine, The University of Hong Kong, Hong Kong, Special Administrative Region, People's Republic of China
| |
Collapse
|
23
|
Skidmore JM, Waite MR, Alvarez-Bolado G, Puelles L, Martin DM. A novel TaulacZ allele reveals a requirement for Pitx2 in formation of the mammillothalamic tract. Genesis 2012; 50:67-73. [DOI: 10.1002/dvg.20793] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 08/04/2011] [Accepted: 08/19/2011] [Indexed: 12/25/2022]
|
24
|
Waite MR, Skaggs K, Kaviany P, Skidmore JM, Causeret F, Martin JF, Martin DM. Distinct populations of GABAergic neurons in mouse rhombomere 1 express but do not require the homeodomain transcription factor PITX2. Mol Cell Neurosci 2012; 49:32-43. [PMID: 21925604 PMCID: PMC3244529 DOI: 10.1016/j.mcn.2011.08.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 08/04/2011] [Accepted: 08/30/2011] [Indexed: 11/20/2022] Open
Abstract
Hindbrain rhombomere 1 (r1) is located caudal to the isthmus, a critical organizer region, and rostral to rhombomere 2 in the developing mouse brain. Dorsal r1 gives rise to the cerebellum, locus coeruleus, and several brainstem nuclei, whereas cells from ventral r1 contribute to the trochlear and trigeminal nuclei as well as serotonergic and GABAergic neurons of the dorsal raphe. Recent studies have identified several molecular events controlling dorsal r1 development. In contrast, very little is known about ventral r1 gene expression and the genetic mechanisms regulating its formation. Neurons with distinct neurotransmitter phenotypes have been identified in ventral r1 including GABAergic, serotonergic, and cholinergic neurons. Here we show that PITX2 marks a distinct population of GABAergic neurons in mouse embryonic ventral r1. This population appears to retain its GABAergic identity even in the absence of PITX2. We provide a comprehensive map of markers that places these PITX2-positive GABAergic neurons in a region of r1 that intersects and is potentially in communication with the dorsal raphe.
Collapse
Affiliation(s)
- Mindy R Waite
- Program in Cell and Molecular Biology, 2966 Taubman Medical Library, University of Michigan, Ann Arbor, MI 48109-0619, USA.
| | - Kaia Skaggs
- Department of Neurology, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Parisa Kaviany
- Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Jennifer M Skidmore
- Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| | - Frédéric Causeret
- Institut Jacques Monod, Université Paris Diderot, CNRS UMR 7592, Sorbonne Paris Cité, Paris, France.
| | - James F Martin
- Department of Molecular Physiology and Biophysics, Baylor College of Medicine, Cardiomyocyte Renewal Lab Texas Heart Institute, Houston Texas, 77030, USA.
| | - Donna M Martin
- Program in Cell and Molecular Biology, 2966 Taubman Medical Library, University of Michigan, Ann Arbor, MI 48109-0619, USA; Department of Pediatrics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA; Department of Human Genetics, 3520A MSRB I, University of Michigan, Ann Arbor, MI, 48019-5652, USA.
| |
Collapse
|
25
|
Zhou Y, Liu D, Kaminski HJ. Pitx2 regulates myosin heavy chain isoform expression and multi-innervation in extraocular muscle. J Physiol 2011; 589:4601-14. [PMID: 21727215 PMCID: PMC3208227 DOI: 10.1113/jphysiol.2011.207076] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2011] [Accepted: 07/04/2011] [Indexed: 11/08/2022] Open
Abstract
Extraocular muscle is fundamentally distinct from other skeletal muscle and demonstrates specific anatomical divisions, unique innervation, diverse myosin isoform expression patterns, a distinct genomic profile and differential involvement in neuromuscular disorders. The paired-like homeodomain transcription factor 2 (Pitx2) is known to regulate the formation of extraocular muscle development and in this report we show that its expression in adulthood also defines certain extraocular muscle traits. We found that expression of slow-MyHC and slow-tonic MyHC, along with contractile regulatory proteins troponin I and troponin T, is reduced during the first 3 weeks after birth in mice with conditional knockout of Pitx2, designated Pitx2(Δflox/Δflox). En grappe endplates, which are normally only found on slow-MyHC expressing fibres, were not identified in the Pitx2(Δflox/Δflox) extraocular muscle, suggesting that altered innervation was responsible for the loss in slow-MyHC expression. Extraocular muscle (EOM)-specific MyHC expressing fibres were dramatically reduced at P14 and rarely detected at 3 months in the Pitx2(Δflox/Δflox) mice. 2A-MyHC fibres, which are excluded from mid-belly region in wild-type mice, dominated the orbital layer with no apparent longitudinal variation in the Pitx2(Δflox/Δflox) mice. Pure 2X-MyHC fibres, only present at distal ends in the wild-type mice, populated the outer global layer in the mid-belly region of the Pitx2(Δflox/Δflox) mice. Pitx2 influences slow-MyHC, slow-tonic MyHC and EOM-MyHC expression in extraocular muscle and its absence leads to increased expression of 2X-MyHC and 2A-MyHC. Precise definition of the regulation of MyHC isoforms in extraocular muscle may allow their rational manipulation, in order to alter muscle contractility for therapeutic purposes.
Collapse
Affiliation(s)
- Yuefang Zhou
- Department of Neurology and Psychiatry, Saint Louis University, St Louis, MO, USA
| | | | | |
Collapse
|
26
|
Waite MR, Skidmore JM, Billi AC, Martin JF, Martin DM. GABAergic and glutamatergic identities of developing midbrain Pitx2 neurons. Dev Dyn 2011; 240:333-46. [PMID: 21246650 PMCID: PMC3079949 DOI: 10.1002/dvdy.22532] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/30/2010] [Indexed: 12/18/2022] Open
Abstract
Pitx2, a paired-like homeodomain transcription factor, is expressed in post-mitotic neurons within highly restricted domains of the embryonic mouse brain. Previous reports identified critical roles for PITX2 in histogenesis of the hypothalamus and midbrain, but the cellular identities of PITX2-positive neurons in these regions were not fully explored. This study characterizes Pitx2 expression with respect to midbrain transcription factor and neurotransmitter phenotypes in mid-to-late mouse gestation. In the dorsal midbrain, we identified Pitx2-positive neurons in the stratum griseum intermedium (SGI) as GABAergic and observed a requirement for PITX2 in GABAergic differentiation. We also identified two Pitx2-positive neuronal populations in the ventral midbrain, the red nucleus, and a ventromedial population, both of which contain glutamatergic precursors. Our data suggest that PITX2 is present in regionally restricted subpopulations of midbrain neurons and may have unique functions that promote GABAergic and glutamatergic differentiation.
Collapse
Affiliation(s)
- MR Waite
- Cellular & Molecular Biology Program, The University of Michigan, Ann Arbor, MI 48109
| | - JM Skidmore
- Department of Pediatrics, The University of Michigan, Ann Arbor, MI 48109
| | - AC Billi
- Department of Human Genetics, The University of Michigan, Ann Arbor, MI 48109
| | - JF Martin
- Institute of Biosciences and Technology, Texas A&M System Health Science Center, Houston, TX 77030
| | - DM Martin
- Department of Pediatrics, The University of Michigan, Ann Arbor, MI 48109
- Department of Human Genetics, The University of Michigan, Ann Arbor, MI 48109
| |
Collapse
|
27
|
Markitantova YV, Firsova NV, Smirnova YA, Panova IG, Sukhikh GT, Zinovieva RD, Mitashov VI. Localization of the PITX2 gene expression in human eye cells in the course of prenatal development. BIOL BULL+ 2011. [DOI: 10.1134/s1062359008020039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
28
|
Zacharias AL, Lewandoski M, Rudnicki MA, Gage PJ. Pitx2 is an upstream activator of extraocular myogenesis and survival. Dev Biol 2011; 349:395-405. [PMID: 21035439 PMCID: PMC3019256 DOI: 10.1016/j.ydbio.2010.10.028] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2010] [Revised: 10/05/2010] [Accepted: 10/21/2010] [Indexed: 11/20/2022]
Abstract
The transcription factors required to initiate myogenesis in branchial arch- and somite-derived muscles are known, but the comparable upstream factors required during extraocular muscle development have not been identified. We show Pax7 is dispensable for extraocular muscle formation, whereas Pitx2 is cell-autonomously required to prevent apoptosis of the extraocular muscle primordia. The survival requirement for Pitx2 is stage-dependent and ends following stable activation of genes for the muscle regulatory factors (e.g. Myf5, MyoD), which is reduced in the absence of Pitx2. Further, PITX2 binds and activates transcription of the Myf5 and MyoD promoters, indicating these genes are direct targets. Collectively, these data demonstrate that PITX2 is required at several steps in the development of extraocular muscles, acting first as an anti-apoptotic factor in pre-myogenic mesoderm, and subsequently to activate the myogenic program in these cells. Thus, Pitx2 is the first demonstrated upstream activator of myogenesis in the extraocular muscles.
Collapse
Affiliation(s)
- Amanda L. Zacharias
- Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| | - Mark Lewandoski
- Cancer and Developmental Biology Laboratory, National Cancer Institute, NCI-Fredrick, Fredrick, MD 21702, USA
| | - Michael A. Rudnicki
- The Sprott Center for Stem Cell Research, Ottawa Hospital Research Institute Regenerative Medicine Program, Ottawa, Canada K1H 8L6
- Department of Medicine, University of Ottawa, Ottawa, Canada K1H 8L6
| | - Philip J. Gage
- Department of Ophthalmology & Visual Science, University of Michigan Medical School, Ann Arbor, MI 48105, USA
- Department of Cell & Developmental Biology, University of Michigan Medical School, Ann Arbor, MI 48105, USA
| |
Collapse
|
29
|
Hammock EAD, Eagleson KL, Barlow S, Earls LR, Miller DM, Levitt P. Homologs of genes expressed in Caenorhabditis elegans GABAergic neurons are also found in the developing mouse forebrain. Neural Dev 2010; 5:32. [PMID: 21122108 PMCID: PMC3006369 DOI: 10.1186/1749-8104-5-32] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2010] [Accepted: 12/01/2010] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND In an effort to identify genes that specify the mammalian forebrain, we used a comparative approach to identify mouse homologs of transcription factors expressed in developing Caenorhabditis elegans GABAergic neurons. A cell-specific microarray profiling study revealed a set of transcription factors that are highly expressed in embryonic C. elegans GABAergic neurons. RESULTS Bioinformatic analyses identified mouse protein homologs of these selected transcripts and their expression pattern was mapped in the mouse embryonic forebrain by in situ hybridization. A review of human homologs indicates several of these genes are potential candidates in neurodevelopmental disorders. CONCLUSIONS Our comparative approach has revealed several novel candidates that may serve as future targets for studies of mammalian forebrain development.
Collapse
Affiliation(s)
- Elizabeth AD Hammock
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
- Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN 37232, USA
| | - Kathie L Eagleson
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Susan Barlow
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37232-8240, USA
- Siskin Hospital for Physical Rehabilitation, One Siskin Plaza, Chattanooga, TN 37403, USA
| | - Laurie R Earls
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37232-8240, USA
- St Jude Children's Research Hospital, Memphis, TN 38105, USA
| | - David M Miller
- Vanderbilt Kennedy Center, Vanderbilt University, Nashville, TN 37232, USA
- Department of Cell and Developmental Biology, Vanderbilt University, Nashville, TN 37232-8240, USA
- Program in Neuroscience, Vanderbilt University, Nashville, TN 37232-8240, USA
| | - Pat Levitt
- Zilkha Neurogenetic Institute, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| |
Collapse
|
30
|
Hurd EA, Poucher HK, Cheng K, Raphael Y, Martin DM. The ATP-dependent chromatin remodeling enzyme CHD7 regulates pro-neural gene expression and neurogenesis in the inner ear. Development 2010; 137:3139-50. [PMID: 20736290 DOI: 10.1242/dev.047894] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Inner ear neurogenesis is positively regulated by the pro-neural bHLH transcription factors Ngn1 and NeuroD, but the factors that act upstream of this regulation are not well understood. Recent evidence in mouse and Drosophila suggests that neural development depends on proper chromatin remodeling, both for maintenance of neural stem cells and for proper neuronal differentiation. Here, we show that CHD7, an ATP-dependent chromatin remodeling enzyme mutated in human CHARGE syndrome, is necessary for proliferation of inner ear neuroblasts and inner ear morphogenesis. Conditional deletion of Chd7 in the developing otocyst using Foxg1-Cre resulted in cochlear hypoplasia and complete absence of the semicircular canals and cristae. Conditional knockout and null otocysts also had reductions in vestibulo-cochlear ganglion size and neuron number in combination with reduced expression of Ngn1, Otx2 and Fgf10, concurrent with expansion of the neural fate suppressor Tbx1 and reduced cellular proliferation. Heterozygosity for Chd7 mutations had no major effects on expression of otic patterning genes or on cell survival, but resulted in decreased proliferation within the neurogenic domain. These data indicate that epigenetic regulation of gene expression by CHD7 must be tightly coordinated for proper development of inner ear neuroblasts.
Collapse
Affiliation(s)
- Elizabeth A Hurd
- Department of Pediatrics, The University of Michigan, Ann Arbor, MI 48109, USA
| | | | | | | | | |
Collapse
|
31
|
Enjin A, Rabe N, Nakanishi ST, Vallstedt A, Gezelius H, Memic F, Lind M, Hjalt T, Tourtellotte WG, Bruder C, Eichele G, Whelan PJ, Kullander K. Identification of novel spinal cholinergic genetic subtypes disclose Chodl and Pitx2 as markers for fast motor neurons and partition cells. J Comp Neurol 2010; 518:2284-304. [PMID: 20437528 DOI: 10.1002/cne.22332] [Citation(s) in RCA: 91] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Spinal cholinergic neurons are critical for motor function in both the autonomic and somatic nervous systems and are affected in spinal cord injury and in diseases such as amyotrophic lateral sclerosis (ALS) and spinal muscular atrophy. Using two screening approaches and in situ hybridization, we identified 159 genes expressed in typical cholinergic patterns in the spinal cord. These include two general cholinergic neuron markers, one gene exclusively expressed in motor neurons, and nine genes expressed in unknown subtypes of somatic motor neurons. Further, we present evidence that chondrolectin (Chodl) is expressed by fast motor neurons and that estrogen-related receptor beta (ERRbeta) is a candidate marker for slow motor neurons. In addition, we suggest paired-like homeodomain transcription factor 2 (Pitx2) as a marker for cholinergic partition cells.
Collapse
Affiliation(s)
- Anders Enjin
- Department of Neuroscience, Uppsala University, 751 23 Uppsala, Sweden
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Zhou Y, Cheng G, Dieter L, Hjalt TA, Andrade FH, Stahl JS, Kaminski HJ. An altered phenotype in a conditional knockout of Pitx2 in extraocular muscle. Invest Ophthalmol Vis Sci 2009; 50:4531-41. [PMID: 19407022 PMCID: PMC4330467 DOI: 10.1167/iovs.08-2950] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
PURPOSE To determine the temporal and spatial expression of Pitx2, a bicoid-like homeobox transcription factor, during postnatal development of mouse extraocular muscle and to evaluate its role in the growth and phenotypic maintenance of postnatal extraocular muscle. METHODS Mouse extraocular muscles of different ages were examined for the expression of Pitx2 by RT-PCR, q-PCR, and immunostaining. A conditional mutant mouse strain, in which Pitx2 function is inactivated at postnatal day (P)0, was generated with a Cre-loxP strategy. Histology, immunostaining, real-time PCR, in vitro muscle contractility, and in vivo ocular motility were used to study the effect of Pitx2 depletion on extraocular muscle. RESULTS All three Pitx2 isoforms were expressed by extraocular muscle and at higher levels than in other striated muscles. Immunostaining demonstrated the presence of Pitx2 mainly in extraocular muscle myonuclei. However, no obvious expression patterns were observed in terms of anatomic region (orbital versus global layer), innervation zone, or muscle fiber types. The mutant extraocular muscle had no obvious pathology but had altered muscle fiber sizes. Expression levels of myosin isoforms Myh1, Myh6, Myh7, and Myh13 were reduced, whereas Myh2, Myh3, Myh4, and Myh8 were not affected by postnatal loss of Pitx2. In vitro, Pitx2 loss made the extraocular muscles stronger, faster, and more fatigable. Eye movement recordings found saccades to have a lower peak velocity. CONCLUSIONS Pitx2 is important in maintaining the mature extraocular muscle phenotype and regulating the expression of critical contractile proteins. Modulation of Pitx2 expression can influence extraocular muscle function with long-term therapeutic implications.
Collapse
Affiliation(s)
- Yuefang Zhou
- Department of Neurology and Psychiatry, Saint Louis University, St. Louis, Missouri
| | - Georgiana Cheng
- Department of Pathobiology, Cleveland Clinic, Cleveland, Ohio
| | - Lisa Dieter
- Department of Neurology and Psychiatry, Saint Louis University, St. Louis, Missouri
| | - Tord A. Hjalt
- Department of Experimental Medical Research, Lund University, Lund, Sweden
| | | | - John S. Stahl
- Louis Stokes Cleveland VA Medical Center, Cleveland, Ohio
- Department of Neurology, Case Western Reserve University, Cleveland, Ohio
| | - Henry J. Kaminski
- Department of Neurology and Psychiatry, Saint Louis University, St. Louis, Missouri
| |
Collapse
|
33
|
PACS-1 mediates phosphorylation-dependent ciliary trafficking of the cyclic-nucleotide-gated channel in olfactory sensory neurons. J Neurosci 2009; 29:10541-51. [PMID: 19710307 DOI: 10.1523/jneurosci.1590-09.2009] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Impaired ciliary protein transport in olfactory sensory neurons (OSNs) leads to anosmia, and is a newly recognized clinical manifestation of a class of human disorders called ciliopathies. Surprisingly little is known regarding the mechanisms controlling trafficking to this unique neuronal compartment. Here, we show a novel role for phosphofurin acidic cluster-sorting protein 1 (PACS-1) in the ciliary trafficking of the olfactory cyclic-nucleotide-gated (CNG) channel. PACS-1 is an intracellular sorting protein that mediates its effects through the binding of acidic clusters on cargo protein. This interaction is dependent on CK2 phosphorylation of both PACS-1 and its cargo. We show that CNGB1b contains two putative PACS-1 binding sites, which are phosphorylated by the serine/threonine protein kinase, CK2. Additionally, we show that PACS-1 is expressed in OSNs and interacts in complex with the CNG channel. CK2 inhibition in native OSNs causes a loss of CNG channel from cilia and subsequent olfactory dysfunction, while adenoviral expression of mutant PACS-1 causes similar mislocalization. These results provide a mechanism for the subunit-dependent ciliary trafficking of the CNG channel and offer insight into the mechanisms of ciliary transport.
Collapse
|
34
|
Independent and dynamic reallocation of pitx gene expression during vertebrate evolution, with emphasis on fish pituitary development. Gene 2008; 417:19-26. [PMID: 18486365 DOI: 10.1016/j.gene.2008.03.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 03/14/2008] [Accepted: 03/16/2008] [Indexed: 11/22/2022]
Abstract
Several transcription regulators play key roles during pituitary morphogenesis. Well known intrinsic signals of the adenohypophysis such as the K(50)paired-like homeodomain proteins regulate commitment, proliferation, differential specification and maintenance of adenohypophyseal cells. We have cloned and successively characterized the mRNA localization of three pitx gene-pairs and three of their splice variants in salmon, pitx1alpha, pitx1beta; pitx2alpha, pitx2beta; pitx3alpha, pitx3beta; pitx1alphash, pitx1betash and pitx2alphaA. The high level of conservation between the pitx paralog-pairs indicates that they likely arose from lineage-specific genome duplication. We also report the isolation of a pitx1 gene in zebrafish. Comparative ISH studies of zebrafish, salmon and mouse pitx genes indicate both conservation and divergence of spatial expression domains in vertebrates. Significant differences were observed between the expressions of pitx orthologs during pituitary development. We suggest that the ancestral pituitary expression at early and late events of morphogenesis is preserved in different species through complementary shuffling of expression between the distinct pitx members of the family. Moreover, ISH analysis of the pitx salmon repertoire shows rapid evolution in this lineage, differences in spatio-temporal expression are observed between gene duplicates.
Collapse
|
35
|
Skidmore JM, Cramer JD, Martin JF, Martin DM. Cre fate mapping reveals lineage specific defects in neuronal migration with loss of Pitx2 function in the developing mouse hypothalamus and subthalamic nucleus. Mol Cell Neurosci 2008; 37:696-707. [PMID: 18206388 PMCID: PMC2386145 DOI: 10.1016/j.mcn.2007.12.015] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Revised: 11/18/2007] [Accepted: 12/07/2007] [Indexed: 10/22/2022] Open
Abstract
Establishment of neuronal diversity is a central topic in developmental neurobiology. Prior studies implicated Pitx2, a paired-like homeodomain transcription factor, in mouse subthalamic nucleus neuronal development, but precise stages of neuronal differentiation affected (migration, axon outgrowth, fate specification) and underlying mechanisms were unknown. Here we report lineage tracing experiments using Pitx2(cre/+), Pitx2(cre/null), and conditional nuclear lacZ reporter mice to track embryonic Pitx2 expressing neurons. Migration of subthalamic nucleus and hypothalamic neurons was severely arrested in Pitx2(cre/null) embryos, and subclasses of subthalamic nucleus neurons identified by Lmx1b, Foxp1, and Foxp2-gene expression revealed differing sensitivities to Pitx2 dosage. Interestingly, embryonic subthalamic nucleus development was unaffected in Lmx1b null mice, suggesting that Pitx2 and Lmx1b act via independent genetic pathways. These data provide the first direct evidence for Pitx2-dependent neuronal migration in the developing hypothalamus, and demonstrate that complex transcriptional networks regulate regional specialization of distinct hypothalamic and subthalamic nucleus neurons.
Collapse
Affiliation(s)
- Jennifer M. Skidmore
- Department of Pediatrics, The University of Michigan Medical Center, Ann Arbor, Michigan, 48109
| | - John D. Cramer
- Department of Pediatrics, The University of Michigan Medical Center, Ann Arbor, Michigan, 48109
| | - James F. Martin
- Institute of Biosciences and Technology, Texas A&M System Health Science Center, Houston, TX 77030
| | - Donna M. Martin
- Department of Pediatrics, The University of Michigan Medical Center, Ann Arbor, Michigan, 48109
- Department of Human Genetics, The University of Michigan Medical Center, Ann Arbor, Michigan, 48109
| |
Collapse
|
36
|
Vue TY, Aaker J, Taniguchi A, Kazemzadeh C, Skidmore JM, Martin DM, Martin JF, Treier M, Nakagawa Y. Characterization of progenitor domains in the developing mouse thalamus. J Comp Neurol 2008; 505:73-91. [PMID: 17729296 DOI: 10.1002/cne.21467] [Citation(s) in RCA: 113] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
To understand the molecular basis of the specification of thalamic nuclei, we analyzed the expression patterns of various transcription factors and defined progenitor cell populations in the embryonic mouse thalamus. We show that the basic helix-loop-helix (bHLH) transcription factor Olig3 is expressed in the entire thalamic ventricular zone and the zona limitans intrathalamica (ZLI). Next, we define two distinct progenitor domains within the thalamus, which we name pTH-R and pTH-C, located caudal to the ZLI. pTH-R is immediately caudal to the ZLI and expresses Nkx2.2, Mash1, and Olig3. pTH-C is caudal to pTH-R and expresses Ngn1, Ngn2, and Olig3. Short-term lineage analysis of Olig3-, Mash1-, Ngn1-, and Ngn2-expressing progenitor cells as well as tracing the Pitx2 cell lineage suggests that pTH-C is the only major source of thalamic nuclei containing neurons that project to the cerebral cortex, whereas pTH-R and ZLI are likely to produce distinct postmitotic populations outside of the cortex-projecting part of the thalamus. To determine if pTH-C is composed of subdomains, we characterized expression of the homeodomain protein Dbx1 and the bHLH protein Olig2. We show that Dbx1 is expressed in caudodorsal-high to rostroventral-low gradient within pTH-C. Analysis of heterozygous Dbx1(nlslacZ) knockin mice demonstrated that Dbx1-expressing progenitors preferentially give rise to caudodorsal thalamic nuclei. Olig2 is expressed in an opposite gradient within pTH-C to that of Dbx1. These results establish the molecular heterogeneity within the progenitor cells of the thalamus, and suggest that such heterogeneity contributes to the specification of thalamic nuclei.
Collapse
Affiliation(s)
- Tou Yia Vue
- Department of Neuroscience, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
37
|
Robertson B, Auclair F, Ménard A, Grillner S, Dubuc R. GABA distribution in lamprey is phylogenetically conserved. J Comp Neurol 2007; 503:47-63. [PMID: 17480011 DOI: 10.1002/cne.21348] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The localization of gamma-aminobutyric acid (GABA) has been well described in most classes of vertebrates but not in adult lampreys. The question if the GABA distribution is similar throughout the vertebrate subphylum is therefore still to be addressed. We here investigate two lamprey species, the sea lamprey, Petromyzon marinus, and the river lamprey, Lampetra fluviatilis, and compare the GABA pattern with that of other vertebrates. The present immunohistochemical study provides an anatomical basis for the general distribution and precise localization of GABAergic neurons in the adult lamprey forebrain and brainstem. GABA-immunoreactive cells were organized in a virtually identical manner in the two species. They were found throughout the brain, with the following regions being of particular interest: the granular cell layer of the olfactory bulb, the nucleus of the anterior commissure, the septum, the lateral and medial pallia, the striatum, the nucleus of the postoptic commissure, the thalamus, the hypothalamus, and pretectal areas, the optic tectum, the torus semicircularis, the mesencephalic tegmentum, restricted regions of the rhombencephalic tegmentum, the octavolateral area, and the dorsal column nucleus. The GABA distribution found in cyclostomes is very similar to that of other classes of vertebrates, including mammals. Since the lamprey diverged from the main vertebrate line around 450 million years ago, this implies that already at that time the basic vertebrate plan for the GABA innervation in different parts of the brain had been developed.
Collapse
Affiliation(s)
- Brita Robertson
- Nobel Institute for Neurophysiology, Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | | | | | | | | |
Collapse
|
38
|
Hurd EA, Capers PL, Blauwkamp MN, Adams ME, Raphael Y, Poucher HK, Martin DM. Loss of Chd7 function in gene-trapped reporter mice is embryonic lethal and associated with severe defects in multiple developing tissues. Mamm Genome 2007; 18:94-104. [PMID: 17334657 DOI: 10.1007/s00335-006-0107-6] [Citation(s) in RCA: 129] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2006] [Accepted: 11/16/2006] [Indexed: 12/23/2022]
Abstract
CHD7 is a novel chromodomain gene mutated in 60%-80% of humans with CHARGE syndrome, a multiple congenital anomaly condition characterized by ocular coloboma, heart defects, atresia of the choanae, retarded growth and development, genital hypoplasia, and characteristic ear abnormalities including deafness. Phenotypic features of CHARGE are highly variable and incompletely penetrant. To explore developmental roles of CHD7, we generated mice carrying the Chd7(Gt) allele from a Chd7-deficient, gene-trapped lacZ reporter ES cell line. RT-PCR of embryo RNA demonstrated significantly reduced levels of wild-type transcript in Chd7(Gt/Gt) embryos. Chd7(Gt/Gt) embryos survive only up to embryonic day 10.5 (E10.5). Chd7(Gt/+) male and female mice are viable, small, and exhibit variable degrees of head-bobbing and circling, consistent with vestibular dysfunction. Paint-filling of E16.5 heterozygous inner ears revealed defects of the semicircular canals. The pattern of beta-galactosidase activity in Chd7(Gt/+) embryos mimics Chd7 mRNA expression in wild-type embryos, confirming the fidelity of the lacZ reporter. We observed tissue-specific beta-galactosidase in the E12.5 and E14.5 Chd7(Gt/+) brain, pituitary, ear, heart, and craniofacial structures, indicating survival of Chd7(Gt/+) cells in CHARGE-relevant organs. These studies demonstrate the utility of Chd7(Gt) as a reporter-tagged loss-of-function allele for future studies exploring developmental mechanisms of Chd7 deficiency.
Collapse
Affiliation(s)
- Elizabeth A Hurd
- Department of Pediatrics, The University of Michigan Medical Center, Ann Arbor, Michigan 48109-0652, USA
| | | | | | | | | | | | | |
Collapse
|
39
|
Inverardi F, Beolchi MS, Ortino B, Moroni RF, Regondi MC, Amadeo A, Frassoni C. GABA immunoreactivity in the developing rat thalamus and Otx2 homeoprotein expression in migrating neurons. Brain Res Bull 2007; 73:64-74. [PMID: 17499638 DOI: 10.1016/j.brainresbull.2007.02.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2006] [Revised: 02/05/2007] [Accepted: 02/06/2007] [Indexed: 10/23/2022]
Abstract
We investigated the expression of gamma-aminobutyric acid (GABA) in the developing rat thalamus by immunohistochemistry, using light, confocal and electron microscopy. We also examined the relationship between the expression of the homeoprotein Otx2, a transcription factor implicated in brain regionalization, and the radial and non-radial migration of early generated thalamic neurons, identified by the neuronal markers calretinin (CR) and GABA. The earliest thalamic neurons generated between embryonic days (E) 13 and 15 include those of the reticular nucleus, entirely composed by GABAergic neurons. GABA immunoreactivity appeared at E14 in immature neurons and processes laterally to the neuroepithelium of the diencephalic vesicle. The embryonic and perinatal periods were characterized by the presence of abundant GABA-immunoreactive fibers, mostly tangentially oriented, and of growth cones. At E15 and E16, GABA was expressed in radially and non-radially oriented neurons in the region of the reticular thalamic migration, between the dorsal and ventral thalamic primordia, and within the dorsal thalamus. At these embryonic stages, some CR- and GABA-immunoreactive migrating-like neurons, located in the migratory stream and in the dorsal thalamus, expressed the homeoprotein Otx2. In the perinatal period, the preponderance of GABAergic neurons was restricted to the reticular nucleus and several GABAergic fibers were still detectable throughout the thalamus. The immunolabeling of fibers progressively decreased and was no longer visible by postnatal day 10, when the adult configuration of GABA immunostaining was achieved. These results reveal the spatio-temporal features of GABA expression in the developing thalamus and suggest a novel role of Otx2 in thalamic cell migration.
Collapse
Affiliation(s)
- F Inverardi
- Dipartimento di Epilettologia Clinica e Neurofisiologia Sperimentale, Fondazione I.R.C.C.S. Istituto Nazionale Neurologico C. Besta, via Celoria 11, 20133 Milano, Italy
| | | | | | | | | | | | | |
Collapse
|
40
|
de la Houssaye G, Bieche I, Roche O, Vieira V, Laurendeau I, Arbogast L, Zeghidi H, Rapp P, Halimi P, Vidaud M, Dufier JL, Menasche M, Abitbol M. Identification of the first intragenic deletion of the PITX2 gene causing an Axenfeld-Rieger Syndrome: case report. BMC MEDICAL GENETICS 2006; 7:82. [PMID: 17134502 PMCID: PMC1684248 DOI: 10.1186/1471-2350-7-82] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/10/2006] [Accepted: 11/29/2006] [Indexed: 11/21/2022]
Abstract
BACKGROUND Axenfeld-Rieger syndrome (ARS) is characterized by bilateral congenital abnormalities of the anterior segment of the eye associated with abnormalities of the teeth, midface, and umbilicus. Most cases of ARS are caused by mutations in the genes encoding PITX2 or FOXC1. Here we describe a family affected by a severe form of ARS. CASE PRESENTATION Two members of this family (father and daughter) presented with typical ARS and developed severe glaucoma. The ocular phenotype was much more severe in the daughter than in the father. Magnetic resonance imaging (MRI) detected an aggressive form of meningioma in the father. There was no mutation in the PITX2 gene, determined by exon screening. We identified an intragenic deletion by quantitative genomic PCR analysis and characterized this deletion in detail. CONCLUSION Our findings implicate the first intragenic deletion of the PITX2 gene in the pathogenesis of a severe form of ARS in an affected family. This study stresses the importance of a systematic search for intragenic deletions in families affected by ARS and in sporadic cases for which no mutations in the exons or introns of PITX2 have been found. The molecular genetics of some ARS pedigrees should be re-examined with enzymes that can amplify medium and large genomic fragments.
Collapse
Affiliation(s)
- Guillaume de la Houssaye
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
| | - Ivan Bieche
- Laboratoire de Génétique Moleculaire-INSERM U745, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris V, Paris, France
| | - Olivier Roche
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
- CHU Necker Enfants Malades, Service d'ophtalmologie, 149, rue de Sèvres 75 Paris cedex 15, France
| | - Véronique Vieira
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
| | - Ingrid Laurendeau
- Laboratoire de Génétique Moleculaire-INSERM U745, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris V, Paris, France
| | - Laurence Arbogast
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
| | - Hatem Zeghidi
- CHU Necker Enfants Malades, Service d'ophtalmologie, 149, rue de Sèvres 75 Paris cedex 15, France
| | - Philippe Rapp
- CHU Necker Enfants Malades, Service d'ophtalmologie, 149, rue de Sèvres 75 Paris cedex 15, France
| | - Philippe Halimi
- Service de radiologie et d'imagerie médicale de Hôpital Européen Georges Pompidou, 20-40 Rue Leblanc, 75908 Paris Cedex 15, France
| | - Michel Vidaud
- Laboratoire de Génétique Moleculaire-INSERM U745, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris V, Paris, France
| | - Jean-Louis Dufier
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
- CHU Necker Enfants Malades, Service d'ophtalmologie, 149, rue de Sèvres 75 Paris cedex 15, France
| | - Maurice Menasche
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
| | - Marc Abitbol
- Centre de Recherche Thérapeutique en Ophtalmologie, EA n°2502, Faculté de Médecine René Descartes, site Necker, 156 rue de Vaugirard 75730 Paris cedex 15, Université Paris V, Paris, France
- CHU Necker Enfants Malades, Service d'ophtalmologie, 149, rue de Sèvres 75 Paris cedex 15, France
| |
Collapse
|
41
|
Markitantova YV, Smirnova YA, Panova IG, Sukhikh GT, Zinov’eva RD, Mitashov VI. Analysis of expression of regulatory genes Pax6, Prox1, and Pitx2 in differentiating eye cells in human fetus. BIOL BULL+ 2006. [DOI: 10.1134/s1062359006040042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
42
|
Sclafani AM, Skidmore JM, Ramaprakash H, Trumpp A, Gage PJ, Martin DM. Nestin-Cre mediated deletion of Pitx2 in the mouse. Genesis 2006; 44:336-44. [PMID: 16823861 DOI: 10.1002/dvg.20220] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Nestin-Cre mice are widely used to generate gene deletions in the developing brain. Surprisingly, fewNestin-Cre lines have been characterized for their temporal and brain region-specific recombination. In addition, some Nestin-Cre lines express Cre outside the central nervous system, making it difficult to choose appropriate lines for targeting genes with brain region-restricted expression. Here we describe the properties of a Nestin-Cre transgenic line and its use for conditional deletions of Pitx2, a paired-like homeodomain transcription factor. We report that Nestin-Cre conditional Pitx2 mutant mice have ocular and craniofacial defects consistent with the role of human PITX2 in Rieger syndrome. Conditional mutants exhibit defects in midbrain neuronal development similar to those in Pitx2 homozygous null embryos, but lack the abnormalities in subthalamic nucleus neurons that occur with complete loss of Pitx2 function. These data indicate that normal differentiation of midbrain neurons depends upon adequate Pitx2 function during the period of active neurogenesis.
Collapse
Affiliation(s)
- Anthony M Sclafani
- Molecular, Cellular and Developmental Biology Graduate Program, Yale College of Medicine, New Haven, Connecticut, USA
| | | | | | | | | | | |
Collapse
|
43
|
Mueller T, Vernier P, Wullimann MF. A phylotypic stage in vertebrate brain development: GABA cell patterns in zebrafish compared with mouse. J Comp Neurol 2006; 494:620-34. [PMID: 16374795 DOI: 10.1002/cne.20824] [Citation(s) in RCA: 111] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
A recent comparison of early forebrain gene expression in mouse and zebrafish revealed highly comparable expression patterns of developmentally relevant genes, for example, of proneural (Neurogenin1, NeuroD, Mash1/Zash1a) genes involved in neurogenesis at a particular time window (mouse: embryonic day 12.5/13.5; zebrafish: 3 days). Here we extend this analysis to the description of gamma-aminobutyric acid (GABA) cell patterns in the early postembryonic zebrafish brain (i.e., during early secondary neurogenesis). We find again an astonishing degree of correspondences of GABA cell patterns between zebrafish and mouse during this previously established critical time window, for example, regarding absence of GABA cells in certain forebrain regions (pallium, dorsal thalamus, eminentia thalami) or with respect to the spatiotemporal occurrence of GABA cells (e.g., late cerebellar GABA cells). Furthermore, there is perfect correlation with previously established proneural gene expression patterns (i.e., absence of Mash1/Zash1a gene expression in GABA-cell-free forebrain regions) between mouse and zebrafish. The available information in additional vertebrate species, especially in Xenopus, is also highly consistent with our analysis here and suggests that a "phylotypic stage" of neurogenesis during vertebrate brain development may be present.
Collapse
Affiliation(s)
- Thomas Mueller
- Centre National de la Recherche Scientifique, Institute of Neurobiology A. Fessard, "Development, Evolution, and Plasticity of the Nervous System," Research Unit 2197, 91198 Gif-sur-Yvette, France
| | | | | |
Collapse
|
44
|
Sanchez JF, Crooks DR, Lee CT, Schoen CJ, Amable R, Zeng X, Florival-Victor T, Morales N, Truckenmiller ME, Smith DR, Freed WJ. GABAergic lineage differentiation of AF5 neural progenitor cells in vitro. Cell Tissue Res 2006; 324:1-8. [PMID: 16408195 PMCID: PMC2673919 DOI: 10.1007/s00441-005-0094-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2005] [Accepted: 10/05/2005] [Indexed: 11/30/2022]
Abstract
We have previously described an immortal rat central-nervous-system progenitor cell line, AF5, which is able to exit the cell cycle and assume a differentiated state with neuronal properties. The phenotypic specification of differentiated AF5 cells, however, is not known. In the present study, when induced to differentiate by serum starvation in Neurobasal medium, AF5 cells down-regulate glial fibrillary acidic protein and up-regulate expression of beta-III-tubulin, medium-molecular-weight neurofilament protein, and neuronal growth-associated protein 43. Expression of the gamma-aminobutyric acid (GABA) lineage marker, glutamic acid decarboxylase 67 (GAD67), increases during differentiation, suggesting that AF5 cells adopt a GABAergic lineage. Time-course analysis of the GABAergic neuron specification transcription factor, Pitx2, by reverse transcription/polymerase chain reaction, has shown an increase in the Pitx2 transcript 48 h after initiation of differentiation. In differentiated AF5 cells, expression of the Pitx2 target gene products GAD65 and GABA transporter-1 increases. Cellular GABA levels in differentiated AF5 cells increase by about 26-fold, and GABA release into the medium is 150-fold higher compared with that of undifferentiated cells. Therefore, AF5 cells can be induced to differentiate to a neuronal phenotype with a GABAergic lineage.
Collapse
Affiliation(s)
- Joseph F Sanchez
- Development and Plasticity Section, Cellular Neurobiology Research Branch, Intramural Research Program, National Institute on Drug Abuse, NIH, DHHS, Baltimore, MD 21224, USA.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
45
|
Idrees F, Bloch-Zupan A, Free SL, Vaideanu D, Thompson PJ, Ashley P, Brice G, Rutland P, Bitner-Glindzicz M, Khaw PT, Fraser S, Sisodiya SM, Sowden JC. A novel homeobox mutation in the PITX2 gene in a family with Axenfeld-Rieger syndrome associated with brain, ocular, and dental phenotypes. Am J Med Genet B Neuropsychiatr Genet 2006; 141B:184-91. [PMID: 16389592 DOI: 10.1002/ajmg.b.30237] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Axenfeld-Rieger Syndrome (ARS) is a genetically heterogeneous birth defect characterized by malformation of the anterior segment of the eye associated with glaucoma. Mutation of the PITX2 homeobox gene has been identified as a cause of ARS. We report a novel Arg5Trp missense mutation in the PITX2 homeodomain, which is associated with brain abnormalities. One patient had a small sella turcica likely to reflect hypoplasia of the pituitary gland and consistent with the critical role identified for Pitx2 in pituitary development in mice. Two patients had an enlarged cisterna magna, one with a malformed cerebellum, and two had executive skills deficits one in isolation and one in association with a below average intellectual capacity. The mutation caused a typical ARS ocular phenotype. All affected had iris hypoplasia, anterior iris to corneal adhesions, and corectopia. The ocular phenotype varied significantly in severity and showed some asymmetry. All affected also had redundant peri-umbilical skin, a hypoplastic maxilla, microdontia, and hypodontia missing between 20 and 27 teeth with an unusual pattern of tooth loss. Dental phenotypes were documented as they are often poorly characterized in ARS patients. All affected individuals showed an absence of first permanent molars with variable absence of other rarely absent teeth: the permanent upper central incisors, maxillary and mandibular first and second molars, and the mandibular canines. Based on the distinctive dental anomalies, we suggest that the dental phenotype can assist in predicting the presence of a PITX2 mutation and the possibility of brain abnormalities.
Collapse
Affiliation(s)
- Faisal Idrees
- Developmental Biology Unit, Institute of Child Health and Great Ormond Street Hospital for Children NHS Trust, University College London, London, United Kingdom
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
46
|
Wei Q. Pitx2a binds to human papillomavirus type 18 E6 protein and inhibits E6-mediated P53 degradation in HeLa cells. J Biol Chem 2005; 280:37790-7. [PMID: 16129685 PMCID: PMC1479768 DOI: 10.1074/jbc.m502974200] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Binding of high risk human papillomavirus (HPV) E6 protein to E6-associated protein (E6AP), a cellular ubiquitin-protein ligase, enables E6AP to ubiquitinate p53, leading to p53 degradation in cervical cancer cells such as HeLa cells. Here we report that Pitx2a, a bicoid-type homeodomain transcription factor, can bind to HPV E6 protein and inhibit E6/E6AP-mediated p53 degradation. Deletion of the Pitx2a homeodomain abrogates its ability to bind to HPV E6 protein and to induce p53 accumulation in HeLa cells, suggesting that the homeodomain of Pitx2a is essential for inhibition of E6/E6AP-mediated p53 degradation. Recombinant Pitx2a can also block E6/E6AP-mediated p53 degradation in vitro, indicating that this function of Pitx2a is independent of its transcription activity. Pitx2a does not regulate Hdm2-mediated p53 degradation, because Pitx2a does not affect p53 protein levels in HPV-negative cells, such as HCT116, U2OS, and C33A cells. In addition, Pitx2a-induced p53 is transcriptionally active and maintains its specific DNA binding activity in HeLa cells. Taken together, these findings suggest that, by binding to E6, Pitx2a interferes with E6/E6AP-mediated p53 degradation, leading to the accumulation of functional p53 protein in HeLa cells.
Collapse
Affiliation(s)
- Qize Wei
- Laboratory of Molecular Cardiology, NHLBI, National Institutes of Health, Bethesda, MD 20892, USA.
| |
Collapse
|
47
|
Wang Y, Bagheri-Fam S, Harley VR. SOX13 is up-regulated in the developing mouse neuroepithelium and identifies a sub-population of differentiating neurons. BRAIN RESEARCH. DEVELOPMENTAL BRAIN RESEARCH 2005; 157:201-8. [PMID: 15896852 DOI: 10.1016/j.devbrainres.2004.12.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2004] [Revised: 12/24/2004] [Accepted: 12/29/2004] [Indexed: 12/20/2022]
Abstract
In mammals, most of the twenty SOX (SRY HMG box) transcription factors are expressed during embryogenesis and play an important role in cell fate determination. We show here that SOX13 is expressed in the developing mouse brain and spinal cord from E12.5 to E15.5, where it is largely confined to the differentiating zone rather than to the proliferating zone. In particular, we found that SOX13 expression was activated in a subset of neural progenitors as they exit the cycle of mitosis, migrate away from the ventricular zone, and start to differentiate into neurons. The SOX13 protein always localized to the nuclei of the differentiating neuronal cells, consistent with a role for SOX13 as a transcription factor during neurogenesis. Our data suggest a role for SOX13 in the specification and/or differentiation of a specific subset of neurons in the developing central nervous system.
Collapse
Affiliation(s)
- Yi Wang
- Human Molecular Genetics Laboratory, Prince Henry's Institute of Medical Research, 246 Clayton Road, Clayton, Vic. 3168, Australia
| | | | | |
Collapse
|
48
|
Philips ST, Albin RL, Martin DM. Genetics of subthalamic nucleus in development and disease. Exp Neurol 2005; 192:320-30. [PMID: 15755549 DOI: 10.1016/j.expneurol.2004.11.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2004] [Revised: 11/05/2004] [Accepted: 11/09/2004] [Indexed: 11/16/2022]
Abstract
The subthalamic nucleus (STN) is a crucial node in the basal ganglia. Clinical success in targeting the STN for deep brain stimulation in Parkinson's disease patients has prompted increased interest in understanding STN biology. In this report, we discuss recent evidence for transcription factor mediated regulation of STN development. We also review STN developmental neurobiology and known patterns of gene expression in the developing and mature STN.
Collapse
Affiliation(s)
- Steven T Philips
- Department of Pediatrics, The University of Michigan, Ann Arbor, MI 48109, USA
| | | | | |
Collapse
|
49
|
Otero JJ, Fu W, Kan L, Cuadra AE, Kessler JA. Beta-catenin signaling is required for neural differentiation of embryonic stem cells. Development 2004; 131:3545-57. [PMID: 15262888 DOI: 10.1242/dev.01218] [Citation(s) in RCA: 164] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Culture of embryonic stem (ES) cells at high density inhibits both beta-catenin signaling and neural differentiation. ES cell density does not influence beta-catenin expression, but a greater proportion of beta-catenin is targeted for degradation in high-density cultures. Moreover, in high-density cultures, beta-catenin is preferentially localized to the membrane further reducing beta-catenin signaling. Increasing beta-catenin signaling by treatment with Wnt3a-conditioned medium, by overexpression of beta-catenin, or by overexpression of a dominant-negative form of E-cadherin promotes neurogenesis. Furthermore, beta-catenin signaling is sufficient to induce neurogenesis in high-density cultures even in the absence of retinoic acid (RA), although RA potentiates the effects of beta-catenin. By contrast, RA does not induce neurogenesis in high-density cultures in the absence of beta-catenin signaling. Truncation of the armadillo domain of beta-catenin, but not the C terminus or the N terminus, eliminates its proneural effects. The proneural effects of beta-catenin reflect enhanced lineage commitment rather than proliferation of neural progenitor cells. Neurons induced by beta-catenin overexpression either alone or in association with RA express the caudal neuronal marker Hoxc4. However, RA treatment inhibits the beta-catenin-mediated generation of tyrosine hydroxylase-positive neurons, suggesting that not all of the effects of RA are dependent upon beta-catenin signaling. These observations suggest that beta-catenin signaling promotes neural lineage commitment by ES cells, and that beta-catenin signaling may be a necessary co-factor for RA-mediated neuronal differentiation. Further, enhancement of beta-catenin signaling with RA treatment significantly increases the numbers of neurons generated from ES cells, thus suggesting a method for obtaining large numbers of neural species for possible use in for ES cell transplantation.
Collapse
Affiliation(s)
- José Javier Otero
- Department of Neurology, Northwestern University Feinberg School of Medicine, 303 East Chicago Avenue, Chicago, IL 60611, USA.
| | | | | | | | | |
Collapse
|
50
|
Jones EG, Rubenstein JLR. Expression of regulatory genes during differentiation of thalamic nuclei in mouse and monkey. J Comp Neurol 2004; 477:55-80. [PMID: 15281080 DOI: 10.1002/cne.20234] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Expression patterns of genes implicated in development of the thalamus were examined in mice and monkeys, using in situ hybridization with RNA probes complementary to Cad6, Dlx1, Dlx2, Dlx5, Gbx2, Id2, and Lef1 cDNAs. Expression patterns were related to the evolving cytoarchitecture in mice at birth (P0) and in adulthood, and in fetal monkeys early and late in the period of gestation when thalamic nuclei are becoming histologically differentiated out of a series of pronuclear masses. At the earlier developmental stage, each gene was expressed in a pattern that appeared to be pronucleus-specific and maintained a nucleus-specific pattern into adulthood, with the possible exception of Gbx2. Each gene displayed a unique expression pattern in the dorsal thalamus, ventral thalamus, and epithalamus, and no gene was expressed throughout all three divisions or in every nucleus of a division. With the exception of Dlx2, whose expression disappeared at the later time point, all continued to be expressed into adulthood at higher levels and with identical patterns. Despite late appearance of gamma-aminobutyric acid (GABA)ergic cells in the dorsal lateral geniculate nucleus of mice, no Dlx genes, which promote formation of a GABAergic phenotype elsewhere, were detected in dorsal thalamus. Each thalamic nucleus was distinguished by expression of a combination of genes, and homologous nuclei in mouse and monkey exhibited the same combination. The presence of a centre médian nucleus and four pulvinar nuclei in monkeys was marked by patterns of expression not found in mice. The centre médian nucleus was marked by high expression of Id2, which was expressed only weakly in very few nuclei of mice.
Collapse
Affiliation(s)
- Edward G Jones
- Center for Neuroscience, University of California, Davis, Davis, California 95616, USA.
| | | |
Collapse
|