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Masuda A, Nishida K, Ajima R, Saga Y, Bakhtan M, Klar A, Hirata T, Zhu Y. A global gene regulatory program and its region-specific regulator partition neurons into commissural and ipsilateral projection types. SCIENCE ADVANCES 2024; 10:eadk2149. [PMID: 38781326 PMCID: PMC11114196 DOI: 10.1126/sciadv.adk2149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 04/16/2024] [Indexed: 05/25/2024]
Abstract
Understanding the genetic programs that drive neuronal diversification into classes and subclasses is key to understand nervous system development. All neurons can be classified into two types: commissural and ipsilateral, based on whether their axons cross the midline or not. However, the gene regulatory program underlying this binary division is poorly understood. We identified a pair of basic helix-loop-helix transcription factors, Nhlh1 and Nhlh2, as a global transcriptional mechanism that controls the laterality of all floor plate-crossing commissural axons in mice. Mechanistically, Nhlh1/2 play an essential role in the expression of Robo3, the key guidance molecule for commissural axon projections. This genetic program appears to be evolutionarily conserved in chick. We further discovered that Isl1, primarily expressed in ipsilateral neurons within neural tubes, negatively regulates the Robo3 induction by Nhlh1/2. Our findings elucidate a gene regulatory strategy where a conserved global mechanism intersects with neuron class-specific regulators to control the partitioning of neurons based on axon laterality.
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Affiliation(s)
- Aki Masuda
- National Institute of Genetics, Graduate University for Advanced Studies, Sokendai, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Kazuhiko Nishida
- Department of Medical Chemistry, Kansai Medical University, Hirakata, Osaka 573-1010, Japan
| | - Rieko Ajima
- National Institute of Genetics, Graduate University for Advanced Studies, Sokendai, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Yumiko Saga
- National Institute of Genetics, Graduate University for Advanced Studies, Sokendai, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Marah Bakhtan
- Department of Medical Neurobiology, IMRIC, Hebrew University - Hadassah Medical School, Jerusalem, Israel
| | - Avihu Klar
- Department of Medical Neurobiology, IMRIC, Hebrew University - Hadassah Medical School, Jerusalem, Israel
| | - Tatsumi Hirata
- National Institute of Genetics, Graduate University for Advanced Studies, Sokendai, Yata 1111, Mishima, Shizuoka 411-8540, Japan
| | - Yan Zhu
- National Institute of Genetics, Graduate University for Advanced Studies, Sokendai, Yata 1111, Mishima, Shizuoka 411-8540, Japan
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2
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Tran HN, Nguyen QH, Jeong JE, Loi DL, Nam YH, Kang TH, Yoon J, Baek K, Jeong Y. The embryonic patterning gene Dbx1 governs the survival of the auditory midbrain via Tcf7l2-Ap2δ transcriptional cascade. Cell Death Differ 2023; 30:1563-1574. [PMID: 37081114 PMCID: PMC10244374 DOI: 10.1038/s41418-023-01165-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2022] [Revised: 04/03/2023] [Accepted: 04/05/2023] [Indexed: 04/22/2023] Open
Abstract
At the top of the midbrain is the inferior colliculus (IC), which functions as the major hub for processing auditory information. Despite the functional significance of neurons in the IC, our understanding of their formation is limited. In this study, we identify the embryonic patterning gene Dbx1 as a key molecular player that governs genetic programs for IC survival. We find that Dbx1 plays a critical role in preventing apoptotic cell death in postnatal IC by transcriptionally repressing c-Jun and pro-apoptotic BH3 only factors. Furthermore, by employing combined approaches, we uncover that Tcf7l2 functions downstream of Dbx1. Loss of Tcf7l2 function causes IC phenotypes with striking similarity to those of Dbx1 mutant mice, which include defective embryonic maturation and postnatal deletion of the IC. Finally, we demonstrate that the Dbx1-Tcf7l2 cascade functions upstream of Ap-2δ, which is essential for IC development and survival. Together, these results unravel a novel molecular mechanism for IC maintenance, which is indispensable for normal brain development.
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Affiliation(s)
- Hong-Nhung Tran
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Quy-Hoai Nguyen
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Ji-Eun Jeong
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Duc-Linh Loi
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Youn Hee Nam
- Department of Oriental Medicine Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Tong Ho Kang
- Department of Oriental Medicine Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Jaeseung Yoon
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Kwanghee Baek
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea
| | - Yongsu Jeong
- Department of Genetics and Biotechnology, College of Life Sciences, Graduate School of Biotechnology, Kyung Hee University, Yongin, Gyeonggi, Republic of Korea.
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3
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Neha S, Dholaniya PS. The Prevailing Role of Topoisomerase 2 Beta and its Associated Genes in Neurons. Mol Neurobiol 2021; 58:6443-6459. [PMID: 34546528 DOI: 10.1007/s12035-021-02561-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 09/11/2021] [Indexed: 12/01/2022]
Abstract
Topoisomerase 2 beta (TOP2β) is an enzyme that alters the topological states of DNA by making a transient double-strand break during the transcription process. The direct interaction of TOP2β with DNA strand results in transcriptional regulation of certain genes and some studies have suggested that a particular set of genes are regulated by TOP2β, which have a prominent role in various stages of neuron from development to degeneration. In this review, we discuss the role of TOP2β in various phases of the neuron's life. Based on the existing reports, we have compiled the list of genes, which are directly regulated by the enzyme, from different studies and performed their functional classification. We discuss the role of these genes in neurogenesis, neuron migration, fate determination, differentiation and maturation, generation of neural circuits, and senescence.
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Affiliation(s)
- Neha S
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500 046, India
| | - Pankaj Singh Dholaniya
- Department of Biotechnology and Bioinformatics, School of Life Sciences, University of Hyderabad, Hyderabad, Telangana, 500 046, India.
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4
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Du A, Wu X, Chen H, Bai QR, Han X, Liu B, Zhang X, Ding Z, Shen Q, Zhao C. Foxg1 Directly Represses Dbx1 to Confine the POA and Subsequently Regulate Ventral Telencephalic Patterning. Cereb Cortex 2020; 29:4968-4981. [PMID: 30843579 DOI: 10.1093/cercor/bhz037] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Revised: 02/01/2019] [Accepted: 02/11/2019] [Indexed: 12/17/2022] Open
Abstract
During early development, signaling centers, such as the cortical hem and the preoptic area (POA), are critical for telencephalic patterning. However, the mechanisms underlying the maintenance of signal centers are poorly understood. Here, we report that the transcription factor Foxg1 is required to confine the POA, a resource of Sonic Hedgehog (Shh) that is pivotal for ventral telencephalic development. Cell-specific deletion of Foxg1 achieved by crossing Foxg1fl/fl with Dbx1-cre or Nestin-CreER combined with tamoxifen induction results in a dramatic expansion of the POA accompanied by the significantly increased activity of the Shh signaling pathway. Ventral pattern formation was severely impaired. Moreover, we demonstrated that Foxg1 directly represses Dbx1 to restrict the POA. Furthermore, we found that the ventral pallium was expanded, which might also contribute to the observed patterning defects. These findings will improve our understanding of the maintenance of signal centers and help to elucidate the mechanisms underlying ventral telencephalic patterning.
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Affiliation(s)
- Ailing Du
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiaojing Wu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Hanhan Chen
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Qing-Ran Bai
- Tongji Hospital, Brain and Spinal Cord Innovative Research Center, School of Life Sciences and Technology, Tongji University, Shanghai 200065, China
| | - Xiao Han
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Bin Liu
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Xiaohu Zhang
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Zhaoying Ding
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
| | - Qin Shen
- Tongji Hospital, Brain and Spinal Cord Innovative Research Center, School of Life Sciences and Technology, Tongji University, Shanghai 200065, China
| | - Chunjie Zhao
- Key Laboratory of Developmental Genes and Human Diseases, MOE, Department of histology and embryology, School of Medicine, Southeast University, Nanjing 210009, China
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5
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Graham DL, Durai HH, Trammell TS, Noble BL, Mortlock DP, Galli A, Stanwood GD. A novel mouse model of glucagon-like peptide-1 receptor expression: A look at the brain. J Comp Neurol 2020; 528:2445-2470. [PMID: 32170734 DOI: 10.1002/cne.24905] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 03/07/2020] [Accepted: 03/10/2020] [Indexed: 12/18/2022]
Abstract
Glucagon-like peptide-1 (GLP-1) is an incretin hormone with a number of functions to maintain energy homeostasis and contribute to motivated behavior, both peripherally and within the central nervous system (CNS). These functions, which include insulin secretion, gastric emptying, satiety, and the hedonic aspects of food and drug intake, are primarily mediated through stimulation of the GLP-1 receptor. While this receptor plays an important role in a variety of physiological outcomes, data regarding its CNS expression has been primarily limited to regional receptor binding and single-label transcript expression studies. We thus developed a bacterial artificial chromosome transgenic mouse, in which expression of a red fluorescent protein (mApple) is driven by the GLP-1R promoter. Using this reporter mouse, we characterized the regional and cellular expression patterns of GLP-1R expressing cells in the CNS, using double-label immunohistochemistry and in situ hybridization. GLP-1R-expressing cells were enriched in several key brain regions and circuits, including the lateral septum, hypothalamus, amygdala, bed nucleus of the stria terminalis, hippocampus, ventral midbrain, periaqueductal gray, and cerebral cortex. In most regions, GLP-1R primarily colocalized with GABAergic neurons, except within some regions such as the hippocampus, where it was co-expressed in glutamatergic neurons. GLP-1R-mApple cells were highly co-expressed with 5-HT3 receptor-containing neurons within the cortex and striatum, as well as with dopamine receptor- and calbindin-expressing cells within the lateral septum, the brain region in which GLP-1R is most highly expressed. In this manuscript, we provide detailed images of GLP-1R-mApple expression and distribution within the brain and characterization of these neurons.
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Affiliation(s)
- Devon L Graham
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Heather H Durai
- Department of Pharmacology, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Taylor S Trammell
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Brenda L Noble
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
| | - Douglas P Mortlock
- Vanderbilt Genetics Institute and Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee, USA
| | - Aurelio Galli
- Department of Surgery, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Gregg D Stanwood
- Department of Biomedical Sciences and Center for Brain Repair, Florida State University College of Medicine, Tallahassee, Florida, USA
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6
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Kikkawa T, Sakayori N, Yuuki H, Katsuyama Y, Matsuzaki F, Konno D, Abe T, Kiyonari H, Osumi N. Dmrt
genes participate in the development of Cajal‐Retzius cells derived from the cortical hem in the telencephalon. Dev Dyn 2020; 249:698-710. [DOI: 10.1002/dvdy.156] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 01/21/2020] [Accepted: 01/27/2020] [Indexed: 01/11/2023] Open
Affiliation(s)
- Takako Kikkawa
- Department of Developmental NeuroscienceUnited Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine Sendai Miyagi Japan
| | - Nobuyuki Sakayori
- Department of Molecular GeneticsInstitute of Biomedical Sciences, Fukushima Medical University Fukushima Japan
| | - Hayato Yuuki
- Department of Developmental NeuroscienceUnited Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine Sendai Miyagi Japan
| | - Yu Katsuyama
- Department of AnatomyShiga University of Medical Science Otsu Shiga Japan
| | - Fumio Matsuzaki
- Laboratory for Cell AsymmetryRIKEN Center for Biosystems Dynamics Research Kobe Japan
| | - Daijiro Konno
- Laboratory for Cell AsymmetryRIKEN Center for Biosystems Dynamics Research Kobe Japan
- Department of PathophysiologyMedical Institute of Bioregulation, Kyushu University Fukuoka Japan
| | - Takaya Abe
- Laboratory for Animal Resources and Genetic EngineeringRIKEN Center for Biosystems Dynamics Research Kobe Japan
| | - Hiroshi Kiyonari
- Laboratory for Animal Resources and Genetic EngineeringRIKEN Center for Biosystems Dynamics Research Kobe Japan
| | - Noriko Osumi
- Department of Developmental NeuroscienceUnited Centers for Advanced Research and Translational Medicine (ART), Tohoku University Graduate School of Medicine Sendai Miyagi Japan
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7
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Kaneyama T, Shirasaki R. Post-crossing segment of dI1 commissural axons forms collateral branches to motor neurons in the developing spinal cord. J Comp Neurol 2019; 526:1943-1961. [PMID: 29752714 DOI: 10.1002/cne.24464] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 03/30/2018] [Accepted: 05/03/2018] [Indexed: 11/09/2022]
Abstract
The dI1 commissural axons in the developing spinal cord, upon crossing the midline through the floor plate, make a sharp turn to grow rostrally. These post-crossing axons initially just extend adjacent to the floor plate without entering nearby motor columns. However, it remains poorly characterized how these post-crossing dI1 axons behave subsequently to this process. In the present study, to address this issue, we examined in detail the behavior of post-crossing dI1 axons in mice, using the Atoh1 enhancer-based conditional expression system that enables selective and sparse labeling of individual dI1 axons, together with Hb9 and ChAT immunohistochemistry for precise identification of spinal motor neurons (MNs). We found unexpectedly that the post-crossing segment of dI1 axons later gave off collateral branches that extended laterally to invade motor columns. Interestingly, these collateral branches emerged at around the time when their primary growth cones initiated invasion into motor columns. In addition, although the length of the laterally growing collateral branches increased with age, the majority of them remained within motor columns. Strikingly, these collateral branches further gave rise to multiple secondary branches in the region of MNs that innervate muscles close to the body axis. Moreover, these axonal branches formed presynaptic terminals on MNs. These observations demonstrate that dI1 commissural neurons develop axonal projection to spinal MNs via collateral branches arising later from the post-crossing segment of these axons. Our findings thus reveal a previously unrecognized projection of dI1 commissural axons that may contribute directly to generating proper motor output.
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Affiliation(s)
- Takeshi Kaneyama
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
| | - Ryuichi Shirasaki
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences, Osaka University, Suita, Osaka, 565-0871, Japan
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8
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Molecular Profiling Defines Evolutionarily Conserved Transcription Factor Signatures of Major Vestibulospinal Neuron Groups. eNeuro 2019; 6:eN-NWR-0475-18. [PMID: 30899776 PMCID: PMC6426439 DOI: 10.1523/eneuro.0475-18.2019] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/04/2019] [Accepted: 01/25/2019] [Indexed: 12/24/2022] Open
Abstract
Vestibulospinal neurons are organized into discrete groups projecting from brainstem to spinal cord, enabling vertebrates to maintain proper balance and posture. The two largest groups are the lateral vestibulospinal tract (LVST) group and the contralateral medial vestibulospinal tract (cMVST) group, with different projection lateralities and functional roles. In search of a molecular basis for these differences, we performed RNA sequencing on LVST and cMVST neurons from mouse and chicken embryos followed by immunohistofluorescence validation. Focusing on transcription factor (TF)-encoding genes, we identified TF signatures that uniquely distinguish the LVST from the cMVST group and further parse different rhombomere-derived portions comprising the cMVST group. Immunohistofluorescence assessment of the CNS from spinal cord to cortex demonstrated that these TF signatures are restricted to the respective vestibulospinal groups and some neurons in their immediate vicinity. Collectively, these results link the combinatorial expression of TFs to developmental and functional subdivisions within the vestibulospinal system.
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9
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Yang JLJ, Bertolesi GE, Hehr CL, Johnston J, McFarlane S. Fibroblast growth factor receptor 1 signaling transcriptionally regulates the axon guidance cue slit1. Cell Mol Life Sci 2018; 75:3649-3661. [PMID: 29705951 PMCID: PMC11105281 DOI: 10.1007/s00018-018-2824-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2017] [Revised: 04/19/2018] [Accepted: 04/23/2018] [Indexed: 12/31/2022]
Abstract
Axons sense molecular cues in their environment to arrive at their post-synaptic targets. While many of the molecular cues have been identified, the mechanisms that regulate their spatiotemporal expression remain elusive. We examined here the transcriptional regulation of the guidance gene slit1 both in vitro and in vivo by specific fibroblast growth factor receptors (Fgfrs). We identified an Fgf-responsive 2.3 kb slit1 promoter sequence that recapitulates spatiotemporal endogenous expression in the neural tube and eye of Xenopus embryos. We found that signaling through Fgfr1 is the main regulator of slit1 expression both in vitro in A6 kidney epithelial cells, and in the Xenopus forebrain, even when other Fgfr subtypes are present in cells. These data argue that a specific signaling pathway downstream of Fgfr1 controls in a cell-autonomous manner slit1 forebrain expression and are novel in identifying a specific growth factor receptor for in vivo control of the expression of a key embryonic axon guidance cue.
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Affiliation(s)
- Jung-Lynn Jonathan Yang
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr., NW, Calgary, AB, T2N 4N1, Canada
| | - Gabriel E Bertolesi
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr., NW, Calgary, AB, T2N 4N1, Canada
| | - Carrie L Hehr
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr., NW, Calgary, AB, T2N 4N1, Canada
| | - Jillian Johnston
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr., NW, Calgary, AB, T2N 4N1, Canada
| | - Sarah McFarlane
- Department of Cell Biology and Anatomy, Hotchkiss Brain Institute, Alberta Children's Hospital Research Institute, Cumming School of Medicine, University of Calgary, 3330 Hospital Dr., NW, Calgary, AB, T2N 4N1, Canada.
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10
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Yamashita W, Takahashi M, Kikkawa T, Gotoh H, Osumi N, Ono K, Nomura T. Conserved and divergent functions of Pax6 underlie species-specific neurogenic patterns in the developing amniote brain. Development 2018; 145:145/8/dev159764. [PMID: 29661783 PMCID: PMC5964652 DOI: 10.1242/dev.159764] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 03/20/2018] [Indexed: 12/20/2022]
Abstract
The evolution of unique organ structures is associated with changes in conserved developmental programs. However, characterizing the functional conservation and variation of homologous transcription factors (TFs) that dictate species-specific cellular dynamics has remained elusive. Here, we dissect shared and divergent functions of Pax6 during amniote brain development. Comparative functional analyses revealed that the neurogenic function of Pax6 is highly conserved in the developing mouse and chick pallium, whereas stage-specific binary functions of Pax6 in neurogenesis are unique to mouse neuronal progenitors, consistent with Pax6-dependent temporal regulation of Notch signaling. Furthermore, we identified that Pax6-dependent enhancer activity of Dbx1 is extensively conserved between mammals and chick, although Dbx1 expression in the developing pallium is highly divergent in these species. Our results suggest that spatiotemporal changes in Pax6-dependent regulatory programs contributed to species-specific neurogenic patterns in mammalian and avian lineages, which underlie the morphological divergence of the amniote pallial architectures. Highlighted Article: Pax6 promotes neuronal differentiation in the developing chick and mouse telencephalon via Notch inhibition, whereas its stage-specific function in RGC maintenance in the VZ is unique to mammalian neocortical progenitors.
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Affiliation(s)
- Wataru Yamashita
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-hangi cho, Sakyoku, Kyoto, 606-0823, Japan
| | - Masanori Takahashi
- Division of Biology, Center for Molecular Medicine, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke, Tochigi, 329-0498, Japan
| | - Takako Kikkawa
- Department of Developmental Neuroscience, United Center for Advanced Research and Translational Medicine (ART), Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Hitoshi Gotoh
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-hangi cho, Sakyoku, Kyoto, 606-0823, Japan
| | - Noriko Osumi
- Department of Developmental Neuroscience, United Center for Advanced Research and Translational Medicine (ART), Tohoku University School of Medicine, 2-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi, 980-8575, Japan
| | - Katsuhiko Ono
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-hangi cho, Sakyoku, Kyoto, 606-0823, Japan
| | - Tadashi Nomura
- Developmental Neurobiology, Kyoto Prefectural University of Medicine, INAMORI Memorial Building, 1-5 Shimogamo-hangi cho, Sakyoku, Kyoto, 606-0823, Japan
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11
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Netrin-1 Derived from the Ventricular Zone, but not the Floor Plate, Directs Hindbrain Commissural Axons to the Ventral Midline. Sci Rep 2017; 7:11992. [PMID: 28931893 PMCID: PMC5607380 DOI: 10.1038/s41598-017-12269-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 08/31/2017] [Indexed: 11/08/2022] Open
Abstract
Netrin-1 (Ntn1) emanating from the ventral midline has been thought to act as a long-range diffusible chemoattractant for commissural axons (CAs). However, CAs still grow towards the midline in the absence of the floor plate (FP), a glial structure occupying the midline. Here, using genetically loss-of-function approaches in mice, we show that Ntn1 derived from the ventricular zone (VZ), but not the FP, is crucial for CA guidance in the mouse hindbrain. During the period of CA growth, Ntn1 is expressed in the ventral two-thirds of the VZ, in addition to the FP. Remarkably, deletion of Ntn1 from the VZ and even from the dorsal VZ highly disrupts CA guidance to the midline, whereas the deletion from the FP has little impact on it. We also show that the severities of CA guidance defects found in the Ntn1 conditional mutants were irrelevant to their FP long-range chemoattractive activities. Our results are incompatible with the prevailing view that Ntn1 is an FP-derived long-range diffusible chemoattractant for CAs, but suggest a novel mechanism that VZ-derived Ntn1 directs CAs to the ventral midline by its local actions.
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12
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The molecular mechanisms controlling morphogenesis and wiring of the habenula. Pharmacol Biochem Behav 2017; 162:29-37. [PMID: 28843424 DOI: 10.1016/j.pbb.2017.08.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/01/2017] [Revised: 07/07/2017] [Accepted: 08/21/2017] [Indexed: 11/22/2022]
Abstract
The habenula is an evolutionarily conserved brain region comprising bilaterally paired nuclei that plays a key role in processing reward information and mediating aversive responses to negative stimuli. An important aspect underlying habenula function is relaying information between forebrain and mid- and hindbrain areas. This is mediated by its complex organization into multiple subdomains and corresponding complexity in circuit organization. Additionally, in many species habenular nuclei display left-right differences at the anatomical and functional level. In order to ensure proper functional organization of habenular circuitry, sophisticated molecular programs control the morphogenesis and wiring of the habenula during development. Knowledge of how these mechanisms shape the habenula is crucial for obtaining a complete understanding of this brain region and can provide invaluable tools to study habenula evolution and function. In this review we will discuss how these molecular mechanisms pattern the early embryonic nervous system and control the formation of the habenula, how they shape its asymmetric organization, and how these mechanisms ensure proper wiring of the habenular circuit. Finally, we will address unexplored aspects of habenula development and how these may direct future research.
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Friocourt F, Chédotal A. The Robo3 receptor, a key player in the development, evolution, and function of commissural systems. Dev Neurobiol 2017; 77:876-890. [DOI: 10.1002/dneu.22478] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 12/04/2016] [Accepted: 12/06/2016] [Indexed: 12/15/2022]
Affiliation(s)
- François Friocourt
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision; 17 Rue Moreau Paris 75012 France
| | - Alain Chédotal
- Sorbonne Universités, UPMC Univ Paris 06, INSERM, CNRS, Institut de la Vision; 17 Rue Moreau Paris 75012 France
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Nouri N, Awatramani R. A novel floor plate boundary defined by adjacent En1 and Dbx1 microdomains distinguishes midbrain dopamine and hypothalamic neurons. Development 2017; 144:916-927. [PMID: 28174244 DOI: 10.1242/dev.144949] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 01/18/2017] [Indexed: 12/13/2022]
Abstract
The mesodiencephalic floor plate (mdFP) is the source of diverse neuron types. Yet, how this structure is compartmentalized has not been clearly elucidated. Here, we identify a novel boundary subdividing the mdFP into two microdomains, defined by engrailed 1 (En1) and developing brain homeobox 1 (Dbx1). Utilizing simultaneous dual and intersectional fate mapping, we demonstrate that this boundary is precisely formed with minimal overlap between En1 and Dbx1 microdomains, unlike many other boundaries. We show that the En1 microdomain gives rise to dopaminergic (DA) neurons, whereas the Dbx1 microdomain gives rise to subthalamic (STN), premammillary (PM) and posterior hypothalamic (PH) populations. To determine whether En1 is sufficient to induce DA neuron production beyond its normal limit, we generated a mouse strain that expresses En1 in the Dbx1 microdomain. In mutants, we observed ectopic production of DA neurons derived from the Dbx1 microdomain, at the expense of STN and PM populations. Our findings provide new insights into subdivisions in the mdFP, and will impact current strategies for the conversion of stem cells into DA neurons.
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Affiliation(s)
- Navid Nouri
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
| | - Rajeshwar Awatramani
- Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA
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15
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Hara S, Kaneyama T, Inamata Y, Onodera R, Shirasaki R. Interstitial branch formation within the red nucleus by deep cerebellar nuclei-derived commissural axons during target recognition. J Comp Neurol 2015; 524:999-1014. [DOI: 10.1002/cne.23888] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 07/29/2015] [Accepted: 08/21/2015] [Indexed: 11/08/2022]
Affiliation(s)
- Satoshi Hara
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences; Osaka University; Suita Osaka 565-0871 Japan
| | - Takeshi Kaneyama
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences; Osaka University; Suita Osaka 565-0871 Japan
| | - Yasuyuki Inamata
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences; Osaka University; Suita Osaka 565-0871 Japan
| | - Ryota Onodera
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences; Osaka University; Suita Osaka 565-0871 Japan
| | - Ryuichi Shirasaki
- Cellular and Molecular Neurobiology Laboratory, Graduate School of Frontier Biosciences; Osaka University; Suita Osaka 565-0871 Japan
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16
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Soiza-Reilly M, Saggau P, Arenkiel BR. Neural circuits revealed. Front Neural Circuits 2015; 9:35. [PMID: 26283927 PMCID: PMC4516880 DOI: 10.3389/fncir.2015.00035] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 07/01/2015] [Indexed: 11/13/2022] Open
Affiliation(s)
- Mariano Soiza-Reilly
- Institut du Fer à Moulin (U839), INSERM/Université Pierre et Marie Curie Paris, France
| | - Peter Saggau
- Allen Institute for Brain Science Seattle, WA, USA
| | - Benjamin R Arenkiel
- Department of Molecular and Human Genetics, Baylor College of Medicine Houston, TX, USA
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17
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Sokolowski K, Esumi S, Hirata T, Kamal Y, Tran T, Lam A, Oboti L, Brighthaupt SC, Zaghlula M, Martinez J, Ghimbovschi S, Knoblach S, Pierani A, Tamamaki N, Shah NM, Jones KS, Corbin JG. Specification of select hypothalamic circuits and innate behaviors by the embryonic patterning gene dbx1. Neuron 2015; 86:403-16. [PMID: 25864637 DOI: 10.1016/j.neuron.2015.03.022] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 12/29/2014] [Accepted: 03/03/2015] [Indexed: 12/30/2022]
Abstract
The hypothalamus integrates information required for the production of a variety of innate behaviors such as feeding, mating, aggression, and predator avoidance. Despite an extensive knowledge of hypothalamic function, how embryonic genetic programs specify circuits that regulate these behaviors remains unknown. Here, we find that in the hypothalamus the developmentally regulated homeodomain-containing transcription factor Dbx1 is required for the generation of specific subclasses of neurons within the lateral hypothalamic area/zona incerta (LH) and the arcuate (Arc) nucleus. Consistent with this specific developmental role, Dbx1 hypothalamic-specific conditional-knockout mice display attenuated responses to predator odor and feeding stressors but do not display deficits in other innate behaviors such as mating or conspecific aggression. Thus, activity of a single developmentally regulated gene, Dbx1, is a shared requirement for the specification of hypothalamic nuclei governing a subset of innate behaviors. VIDEO ABSTRACT.
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Affiliation(s)
- Katie Sokolowski
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Shigeyuki Esumi
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA; Graduate School of Medical Sciences, Kumamoto University, 2-39-1 Kurokami, Chuo Ward, Kumamoto, Kumamoto Prefecture 860-0862, Japan
| | - Tsutomu Hirata
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Yasman Kamal
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Tuyen Tran
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Andrew Lam
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Livio Oboti
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Sherri-Chanelle Brighthaupt
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Manar Zaghlula
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Jennifer Martinez
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Svetlana Ghimbovschi
- Center for Genetic Medicine, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Susan Knoblach
- Center for Genetic Medicine, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA
| | - Alessandra Pierani
- Institut Jacques Monod, Universite Paris Diderot, 15 rue Hélène Brion, 75013 Paris, France
| | - Nobuaki Tamamaki
- Graduate School of Medical Sciences, Kumamoto University, 2-39-1 Kurokami, Chuo Ward, Kumamoto, Kumamoto Prefecture 860-0862, Japan
| | - Nirao M Shah
- Department of Anatomy, University of California, San Francisco, 513 Parnassus Avenue, San Francisco, CA 94143, USA
| | - Kevin S Jones
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA; Department of Biology, Howard University, 415 College Street NW, Washington, DC 20059, USA
| | - Joshua G Corbin
- Center for Neuroscience Research, Children's National Medical Center, 111 Michigan Avenue NW, Washington, DC 20010, USA.
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18
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Santiago C, Bashaw GJ. Transcription factors and effectors that regulate neuronal morphology. Development 2015; 141:4667-80. [PMID: 25468936 DOI: 10.1242/dev.110817] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Transcription factors establish the tremendous diversity of cell types in the nervous system by regulating the expression of genes that give a cell its morphological and functional properties. Although many studies have identified requirements for specific transcription factors during the different steps of neural circuit assembly, few have identified the downstream effectors by which they control neuronal morphology. In this Review, we highlight recent work that has elucidated the functional relationships between transcription factors and the downstream effectors through which they regulate neural connectivity in multiple model systems, with a focus on axon guidance and dendrite morphogenesis.
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Affiliation(s)
- Celine Santiago
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Greg J Bashaw
- Department of Neuroscience, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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19
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Chédotal A. Development and plasticity of commissural circuits: from locomotion to brain repair. Trends Neurosci 2014; 37:551-62. [DOI: 10.1016/j.tins.2014.08.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 08/22/2014] [Accepted: 08/25/2014] [Indexed: 01/01/2023]
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