1
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Swiderski DL, Zelditch ML. Complex adaptive landscape for a "Simple" structure: The role of trade-offs in the evolutionary dynamics of mandibular shape in ground squirrels. Evolution 2022; 76:946-965. [PMID: 35398910 PMCID: PMC9320833 DOI: 10.1111/evo.14493] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 03/22/2022] [Accepted: 03/23/2022] [Indexed: 01/21/2023]
Abstract
Trade-offs are inherent features of many biomechanical systems and are often seen as evolutionary constraints. Structural decoupling may provide a way to escape those limits in some systems but not for structures that transmit large forces, such as mammalian mandibles. For such structures to evolve in multiple directions on a complex adaptive landscape, different regions must change shape while maintaining structural integrity. We evaluated the complexity of the adaptive landscape for mandibular shape in Marmotini, a lineage of ground squirrels that varies in the proportions of seeds and foliage in their diets, by comparing the fit of models based on traits that predict changes in mandibular loading. The adaptive landscape was more complex than predicted by a two-peak model with a single dietary shift. The large number of adaptive peaks reflects a high diversity of directions of shape evolution. The number of adaptive peaks also reflects a multiplicity of functional trade-offs posed by the conflicting demands of processing foods with various combinations of material properties. The ability to balance trade-offs for diets with different proportions of the same foods may account for diversification and disparity of lineages in heterogeneous environments. Rather than constraints, trade-offs may be the impetus of evolutionary change.
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Affiliation(s)
- Donald L Swiderski
- Museum of Zoology and Kresge Hearing Research InstituteUniversity of MichiganAnn ArborMichigan48109
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2
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Takahashi M, Nakabayashi T, Mita N, Jin X, Aikawa Y, Sasamoto K, Miyoshi G, Miyata M, Inoue T, Ohshima T. Involvement of Cdk5 activating subunit p35 in synaptic plasticity in excitatory and inhibitory neurons. Mol Brain 2022; 15:37. [PMID: 35484559 PMCID: PMC9052517 DOI: 10.1186/s13041-022-00922-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/14/2022] [Indexed: 11/23/2022] Open
Abstract
Cyclin-dependent kinase 5 (Cdk5) /p35 is involved in many developmental processes of the central nervous system. Cdk5/p35 is also implicated in synaptic plasticity, learning and memory. Several lines of conditional Cdk5 knockout mice (KO) have been generated and have shown different outcomes for learning and memory. Here, we present our analysis of p35 conditional KO mice (p35cKO) in hippocampal pyramidal neurons or forebrain GABAergic neurons using electrophysiological and behavioral methods. In the fear conditioning task, CamKII-p35cKO mice showed impaired memory retention. Furthermore, NMDAR-dependent long-term depression (LTD) induction by low-frequency stimuli in hippocampal slices from CamkII-p35cKO mice was impaired compared to that in control mice. In contrast, Dlx-p35cKO mice showed no abnormalities in behavioral tasks and electrophysiological analysis in their hippocampal slices. These results indicated that Cdk5/p35 in excitatory neurons is important for the hippocampal synaptic plasticity and associative memory retention.
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Affiliation(s)
- Miyuki Takahashi
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Takeru Nakabayashi
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Naoki Mita
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Xiaohua Jin
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Yuta Aikawa
- Laboratory for Neurophysiology, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Kodai Sasamoto
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Goichi Miyoshi
- Department of Neurophysiology, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo, 162-8666, Japan.,Department of Genetic and Behavioral Neuroscience, Gunma University Graduate School of Medicine, 3-39-22 Showa-cho, Maebashi, Gunma, 371-8511, Japan
| | - Mariko Miyata
- Department of Neurophysiology, Tokyo Women's Medical University, 8-1 Kawada-cho, Shinjuku, Tokyo, 162-8666, Japan
| | - Takafumi Inoue
- Laboratory for Neurophysiology, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan
| | - Toshio Ohshima
- Laboratory for Molecular Brain Science, Department of Life Science and Medical Bioscience, Waseda University, 2-2 Wakamatsu-cho, Shinjuku, Tokyo, 162-0056, Japan.
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3
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Leung RF, George AM, Roussel EM, Faux MC, Wigle JT, Eisenstat DD. Genetic Regulation of Vertebrate Forebrain Development by Homeobox Genes. Front Neurosci 2022; 16:843794. [PMID: 35546872 PMCID: PMC9081933 DOI: 10.3389/fnins.2022.843794] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Accepted: 03/14/2022] [Indexed: 01/19/2023] Open
Abstract
Forebrain development in vertebrates is regulated by transcription factors encoded by homeobox, bHLH and forkhead gene families throughout the progressive and overlapping stages of neural induction and patterning, regional specification and generation of neurons and glia from central nervous system (CNS) progenitor cells. Moreover, cell fate decisions, differentiation and migration of these committed CNS progenitors are controlled by the gene regulatory networks that are regulated by various homeodomain-containing transcription factors, including but not limited to those of the Pax (paired), Nkx, Otx (orthodenticle), Gsx/Gsh (genetic screened), and Dlx (distal-less) homeobox gene families. This comprehensive review outlines the integral role of key homeobox transcription factors and their target genes on forebrain development, focused primarily on the telencephalon. Furthermore, links of these transcription factors to human diseases, such as neurodevelopmental disorders and brain tumors are provided.
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Affiliation(s)
- Ryan F. Leung
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
| | - Ankita M. George
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
| | - Enola M. Roussel
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
| | - Maree C. Faux
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
- Department of Surgery, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Jeffrey T. Wigle
- Department of Biochemistry and Medical Genetics, Max Rady College of Medicine, Rady Faculty of Health Sciences, University of Manitoba, Winnipeg, MB, Canada
- Institute of Cardiovascular Sciences, St. Boniface Hospital Albrechtsen Research Centre, Winnipeg, MB, Canada
| | - David D. Eisenstat
- Murdoch Children’s Research Institute, The Royal Children’s Hospital Melbourne, Parkville, VIC, Australia
- Department of Paediatrics, University of Melbourne, Parkville, VIC, Australia
- Department of Medical Genetics, University of Alberta, Edmonton, AB, Canada
- Department of Pediatrics, University of Alberta, Edmonton, AB, Canada
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4
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DLX Genes: Roles in Development and Cancer. Cancers (Basel) 2021; 13:cancers13123005. [PMID: 34203994 PMCID: PMC8232755 DOI: 10.3390/cancers13123005] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2021] [Revised: 06/10/2021] [Accepted: 06/11/2021] [Indexed: 12/14/2022] Open
Abstract
Simple Summary DLX homeobox family genes encode transcription factors that have indispensable roles in embryonic and postnatal development. These genes are critically linked to the morphogenesis of craniofacial structures, branchial arches, forebrain, and sensory organs. DLX genes are also involved in postnatal homeostasis, particularly hematopoiesis and, when dysregulated, oncogenesis. DLX1/2, DLX3/4, and DLX5/6 exist as bigenes on different chromosomes, sharing intergenic enhancers between gene pairs, which allows orchestrated spatiotemporal expression. Genomic alterations of human DLX gene enhancers or coding sequences result in congenital disorders such as split-hand/foot malformation. Aberrant postnatal expression of DLX genes is associated with hematological malignancies, including leukemias and lymphomas. In several mouse models of T-cell lymphoma, Dlx5 has been shown to act as an oncogene by cooperating with activated Akt, Notch1/3, and/or Wnt to drive tumor formation. In humans, DLX5 is aberrantly expressed in lung and ovarian carcinomas and holds promise as a therapeutic target. Abstract Homeobox genes control body patterning and cell-fate decisions during development. The homeobox genes consist of many families, only some of which have been investigated regarding a possible role in tumorigenesis. Dysregulation of HOX family genes have been widely implicated in cancer etiology. DLX homeobox genes, which belong to the NK-like family, exert dual roles in development and cancer. The DLX genes are the key transcription factors involved in regulating the development of craniofacial structures in vertebrates. The three DLX bigenes have overlapping expression in the branchial arches. Disruption of DLX function has destructive consequences in organogenesis and is associated with certain congenital disorders in humans. The role of DLX genes in oncogenesis is only beginning to emerge. DLX2 diminishes cellular senescence by regulating p53 function, whereas DLX4 has been associated with metastasis in breast cancer. In human ovarian cancer cells, DLX5 is essential for regulating AKT signaling, thereby promoting cell proliferation and survival. We previously implicated Dlx5 as an oncogene in murine T-cell lymphoma driven by a constitutively active form of Akt2. In this mouse model, overexpression of Dlx5 was caused by a chromosomal rearrangement that juxtaposed the Tcr-beta promoter region near the Dlx5 locus. Moreover, transgenic mice overexpressing Dlx5, specifically in immature T-cells, develop spontaneous thymic lymphomas. Oncogenesis in this mouse model involves binding of Dlx5 to the Notch1 and Notch3 gene loci to activate their transcription. Dlx5 also cooperates with Akt signaling to accelerate lymphomagenesis by activating Wnt signaling. We also discuss the fact that human DLX5 is aberrantly expressed in several human malignancies.
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Pahle J, Muhia M, Wagener RJ, Tippmann A, Bock HH, Graw J, Herz J, Staiger JF, Drakew A, Kneussel M, Rune GM, Frotscher M, Brunne B. Selective Inactivation of Reelin in Inhibitory Interneurons Leads to Subtle Changes in the Dentate Gyrus But Leaves Cortical Layering and Behavior Unaffected. Cereb Cortex 2021; 30:1688-1707. [PMID: 31667489 PMCID: PMC7132935 DOI: 10.1093/cercor/bhz196] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Reelin is an extracellular matrix protein, known for its dual role in neuronal migration during brain development and in synaptic plasticity at adult stages. During the perinatal phase, Reelin expression switches from Cajal-Retzius (CR) cells, its main source before birth, to inhibitory interneurons (IN), the main source of Reelin in the adult forebrain. IN-derived Reelin has been associated with schizophrenia and temporal lobe epilepsy; however, the functional role of Reelin from INs is presently unclear. In this study, we used conditional knockout mice, which lack Reelin expression specifically in inhibitory INs, leading to a substantial reduction in total Reelin expression in the neocortex and dentate gyrus. Our results show that IN-specific Reelin knockout mice exhibit normal neuronal layering and normal behavior, including spatial reference memory. Although INs are the major source of Reelin within the adult stem cell niche, Reelin from INs does not contribute substantially to normal adult neurogenesis. While a closer look at the dentate gyrus revealed some unexpected alterations at the cellular level, including an increase in the number of Reelin expressing CR cells, overall our data suggest that Reelin derived from INs is less critical for cortex development and function than Reelin expressed by CR cells.
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Affiliation(s)
- Jasmine Pahle
- Institute for Structural Neurobiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Mary Muhia
- Institute of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Robin J Wagener
- Neurology Clinic, University Hospital Heidelberg, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany
| | - Anja Tippmann
- Institute for Structural Neurobiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.,Department of Systems Neuroscience, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, University of Göttingen, 37075 Göttingen, Germany
| | - Hans H Bock
- Clinic of Gastroenterology and Hepatology, Heinrich-Heine-University Düsseldorf, 40225 Düsseldorf, Germany
| | - Janice Graw
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Joachim Herz
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | - Jochen F Staiger
- Institute for Neuroanatomy, University Medical Center Göttingen, Georg-August-University Göttingen, 37075 Göttingen, Germany
| | - Alexander Drakew
- Institute for Structural Neurobiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.,Institute of Clinical Neuroanatomy, Faculty of Medicine, 60590 Frankfurt, Germany
| | - Matthias Kneussel
- Institute of Molecular Neurogenetics, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Gabriele M Rune
- Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Michael Frotscher
- Institute for Structural Neurobiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
| | - Bianka Brunne
- Institute for Structural Neurobiology, Center for Molecular Neurobiology, ZMNH, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany.,Institute of Neuroanatomy, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany
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6
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Poopalasundaram S, Richardson J, Scott A, Donovan A, Liu K, Graham A. Diminution of pharyngeal segmentation and the evolution of the amniotes. ZOOLOGICAL LETTERS 2019; 5:6. [PMID: 30788138 PMCID: PMC6369561 DOI: 10.1186/s40851-019-0123-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 02/05/2019] [Indexed: 06/01/2023]
Abstract
BACKGROUND The pharyngeal arches are a series of bulges found on the lateral surface of the head of vertebrate embryos, and it is within these segments that components of the later anatomy are laid down. In most vertebrates, the post-otic pharyngeal arches will form the branchial apparatus, while in amniotes these segments are believed to generate the larynx. It has been unclear how the development of these segments has been altered with the emergence of the amniotes. RESULTS In this study, we examined the development of pharyngeal arches in amniotes and show that the post-otic pharyngeal arches in this clade are greatly diminished. We find that the post-otic segments do not undergo myogenesis or skeletogenesis, but are remodelled before these processes occur. We also find that nested DLX expression, which is a feature of all the pharyngeal arches in anamniotes, is associated with the anterior segments but less so with the posterior arches in amniotes. We further show that the posterior arches of the mouse embryo fail to properly delineate, which demonstrates the lack of function of these posterior segments in later development. CONCLUSION In amniotes, there has been a loss of the ancestral "branchial" developmental programme that is a general feature of gnathostomes; myogenesis and skeletogenesis This is likely to have facilitated the emergence of the larynx as a new structure not constrained by the segmental organisation of the posterior pharyngeal region.
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Affiliation(s)
| | - Jo Richardson
- Centre for Developmental Neurobiology, King’s College London, London, UK
| | - Annabelle Scott
- Centre for Developmental Neurobiology, King’s College London, London, UK
| | - Alex Donovan
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, SE1 1UL UK
| | - Karen Liu
- Centre for Craniofacial and Regenerative Biology, King’s College London, London, SE1 1UL UK
| | - Anthony Graham
- Centre for Developmental Neurobiology, King’s College London, London, UK
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7
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Active intermixing of indirect and direct neurons builds the striatal mosaic. Nat Commun 2018; 9:4725. [PMID: 30413696 PMCID: PMC6226429 DOI: 10.1038/s41467-018-07171-4] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2017] [Accepted: 10/12/2018] [Indexed: 12/13/2022] Open
Abstract
The striatum controls behaviors via the activity of direct and indirect pathway projection neurons (dSPN and iSPN) that are intermingled in all compartments. While such cellular mosaic ensures the balanced activity of the two pathways, its developmental origin and pattern remains largely unknown. Here, we show that both SPN populations are specified embryonically and intermix progressively through multidirectional iSPN migration. Using conditional mutant mice, we found that inactivation of the dSPN-specific transcription factor Ebf1 impairs selective dSPN properties, including axon pathfinding, while molecular and functional features of iSPN were preserved. Ebf1 mutation disrupted iSPN/dSPN intermixing, resulting in an uneven distribution. Such architectural defect was selective of the matrix compartment, highlighting that intermixing is a parallel process to compartment formation. Our study reveals while iSPN/dSPN specification is largely independent, their intermingling emerges from an active migration of iSPN, thereby providing a novel framework for the building of striatal architecture.
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8
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Chen L, Zhang YH, Zhang Z, Huang T, Cai YD. Inferring Novel Tumor Suppressor Genes with a Protein-Protein Interaction Network and Network Diffusion Algorithms. MOLECULAR THERAPY-METHODS & CLINICAL DEVELOPMENT 2018; 10:57-67. [PMID: 30069494 PMCID: PMC6068090 DOI: 10.1016/j.omtm.2018.06.007] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2018] [Accepted: 06/19/2018] [Indexed: 02/07/2023]
Abstract
Extensive studies on tumor suppressor genes (TSGs) are helpful to understand the pathogenesis of cancer and design effective treatments. However, identifying TSGs using traditional experiments is quite difficult and time consuming. Developing computational methods to identify possible TSGs is an alternative way. In this study, we proposed two computational methods that integrated two network diffusion algorithms, including Laplacian heat diffusion (LHD) and random walk with restart (RWR), to search possible genes in the whole network. These two computational methods were LHD-based and RWR-based methods. To increase the reliability of the putative genes, three strict screening tests followed to filter genes obtained by these two algorithms. After comparing the putative genes obtained by the two methods, we designated twelve genes (e.g., MAP3K10, RND1, and OTX2) as common genes, 29 genes (e.g., RFC2 and GUCY2F) as genes that were identified only by the LHD-based method, and 128 genes (e.g., SNAI2 and FGF4) as genes that were inferred only by the RWR-based method. Some obtained genes can be confirmed as novel TSGs according to recent publications, suggesting the utility of our two proposed methods. In addition, the reported genes in this study were quite different from those reported in a previous one.
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Affiliation(s)
- Lei Chen
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People’s Republic of China
- College of Information Engineering, Shanghai Maritime University, Shanghai 201306, People’s Republic of China
| | - Yu-Hang Zhang
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People’s Republic of China
| | - Zhenghua Zhang
- Department of Clinical Oncology, Jing’an District Centre Hospital of Shanghai (Huashan Hospital Fudan University Jing’An Branch), Shanghai 200040, People’s Republic of China
| | - Tao Huang
- Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People’s Republic of China
- Corresponding author: Tao Huang, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People’s Republic of China.
| | - Yu-Dong Cai
- School of Life Sciences, Shanghai University, Shanghai 200444, People’s Republic of China
- Corresponding author: Yu-Dong Cai, School of Life Sciences, Shanghai University, Shanghai 200444, People’s Republic of China.
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9
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Square T, Jandzik D, Romášek M, Cerny R, Medeiros DM. The origin and diversification of the developmental mechanisms that pattern the vertebrate head skeleton. Dev Biol 2017; 427:219-229. [DOI: 10.1016/j.ydbio.2016.11.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 10/06/2016] [Accepted: 11/20/2016] [Indexed: 01/30/2023]
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10
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Benítez-Burraco A, Lattanzi W, Murphy E. Language Impairments in ASD Resulting from a Failed Domestication of the Human Brain. Front Neurosci 2016; 10:373. [PMID: 27621700 PMCID: PMC5002430 DOI: 10.3389/fnins.2016.00373] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 08/02/2016] [Indexed: 11/16/2022] Open
Abstract
Autism spectrum disorders (ASD) are pervasive neurodevelopmental disorders entailing social and cognitive deficits, including marked problems with language. Numerous genes have been associated with ASD, but it is unclear how language deficits arise from gene mutation or dysregulation. It is also unclear why ASD shows such high prevalence within human populations. Interestingly, the emergence of a modern faculty of language has been hypothesized to be linked to changes in the human brain/skull, but also to the process of self-domestication of the human species. It is our intention to show that people with ASD exhibit less marked domesticated traits at the morphological, physiological, and behavioral levels. We also discuss many ASD candidates represented among the genes known to be involved in the “domestication syndrome” (the constellation of traits exhibited by domesticated mammals, which seemingly results from the hypofunction of the neural crest) and among the set of genes involved in language function closely connected to them. Moreover, many of these genes show altered expression profiles in the brain of autists. In addition, some candidates for domestication and language-readiness show the same expression profile in people with ASD and chimps in different brain areas involved in language processing. Similarities regarding the brain oscillatory behavior of these areas can be expected too. We conclude that ASD may represent an abnormal ontogenetic itinerary for the human faculty of language resulting in part from changes in genes important for the “domestication syndrome” and, ultimately, from the normal functioning of the neural crest.
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Affiliation(s)
| | - Wanda Lattanzi
- Institute of Anatomy and Cell Biology, Università Cattolica del Sacro Cuore Rome, Italy
| | - Elliot Murphy
- Division of Psychology and Language Sciences, University College London London, UK
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11
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Sasamoto K, Nagai J, Nakabayashi T, He X, Ohshima T. Cdk5 is required for the positioning and survival of GABAergic neurons in developing mouse striatum. Dev Neurobiol 2016; 77:483-492. [PMID: 27480591 DOI: 10.1002/dneu.22424] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2016] [Revised: 07/07/2016] [Accepted: 07/28/2016] [Indexed: 12/20/2022]
Abstract
Cyclin-dependent kinase 5 (Cdk5) is a serine/threonine kinase, and its activity is dependent upon an association with a neuron-specific activating subunit. It was previously reported that Cdk5-/- mice exhibit perinatal lethality and defective neuronal positioning. In this study, they focused on the analysis of neuronal positioning of GABAergic neurons in the forebrain. Defective formation of the ventral striatum, nucleus accumbens, and olfactory tubercles was found in Cdk5-/- embryos. To further study this abnormal development, we generated and analyzed Dlx5/6-Cre p35 conditional KO (cKO); p39-/- mice in which forebrain GABAergic neurons have lost their Cdk5 kinase activity. Defective formation of the nucleus accumbens and olfactory tubercles as well as neuronal loss in the striatum of Dlx5/6-Cre p35cKO; p39-/- mice was found. Elevated levels of phosphorylated JNK were observed in neonatal striatal samples from Dlx5/6-Cre p35cKO; p39-/- mice, suggestive of neuronal death. These results indicate that Cdk5 is required for the formation of the ventral striatum in a cell-autonomous manner, and loss of the kinase activity of Cdk5 causes GABAergic neuronal death in the developing mouse forebrain. © 2016 Wiley Periodicals, Inc. Develop Neurobiol 77: 419-437, 2017.
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Affiliation(s)
- Kodai Sasamoto
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 162-8480, Japan
| | - Jun Nagai
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 162-8480, Japan
| | - Takeru Nakabayashi
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 162-8480, Japan
| | - Xiaojuan He
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 162-8480, Japan
| | - Toshio Ohshima
- Department of Life Science and Medical Bioscience, Graduate School of Advanced Science and Engineering, Waseda University, Tokyo, 162-8480, Japan
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12
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Vicente-Sanchez A, Segura L, Pradhan AA. The delta opioid receptor tool box. Neuroscience 2016; 338:145-159. [PMID: 27349452 DOI: 10.1016/j.neuroscience.2016.06.028] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 05/29/2016] [Accepted: 06/16/2016] [Indexed: 12/14/2022]
Abstract
In recent years, the delta opioid receptor has attracted increasing interest as a target for the treatment of chronic pain and emotional disorders. Due to their therapeutic potential, numerous tools have been developed to study the delta opioid receptor from both a molecular and a functional perspective. This review summarizes the most commonly available tools, with an emphasis on their use and limitations. Here, we describe (1) the cell-based assays used to study the delta opioid receptor. (2) The features of several delta opioid receptor ligands, including peptide and non-peptide drugs. (3) The existing approaches to detect delta opioid receptors in fixed tissue, and debates that surround these techniques. (4) Behavioral assays used to study the in vivo effects of delta opioid receptor agonists; including locomotor stimulation and convulsions that are induced by some ligands, but not others. (5) The characterization of genetically modified mice used specifically to study the delta opioid receptor. Overall, this review aims to provide a guideline for the use of these tools with the final goal of increasing our understanding of delta opioid receptor physiology.
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Affiliation(s)
| | - Laura Segura
- Department of Psychiatry, University of Illinois at Chicago, United States
| | - Amynah A Pradhan
- Department of Psychiatry, University of Illinois at Chicago, United States.
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13
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Wise A, Bar-Joseph Z. SMARTS: reconstructing disease response networks from multiple individuals using time series gene expression data. ACTA ACUST UNITED AC 2014; 31:1250-7. [PMID: 25480376 DOI: 10.1093/bioinformatics/btu800] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2014] [Accepted: 11/26/2014] [Indexed: 02/02/2023]
Abstract
MOTIVATION Current methods for reconstructing dynamic regulatory networks are focused on modeling a single response network using model organisms or cell lines. Unlike these models or cell lines, humans differ in their background expression profiles due to age, genetics and life factors. In addition, there are often differences in start and end times for time series human data and in the rate of progress based on the specific individual. Thus, new methods are required to integrate time series data from multiple individuals when modeling and constructing disease response networks. RESULTS We developed Scalable Models for the Analysis of Regulation from Time Series (SMARTS), a method integrating static and time series data from multiple individuals to reconstruct condition-specific response networks in an unsupervised way. Using probabilistic graphical models, SMARTS iterates between reconstructing different regulatory networks and assigning individuals to these networks, taking into account varying individual start times and response rates. These models can be used to group different sets of patients and to identify transcription factors that differentiate the observed responses between these groups. We applied SMARTS to analyze human response to influenza and mouse brain development. In both cases, it was able to greatly improve baseline groupings while identifying key relevant TFs that differ between the groups. Several of these groupings and TFs are known to regulate the relevant processes while others represent novel hypotheses regarding immune response and development. AVAILABILITY AND IMPLEMENTATION Software and Supplementary information are available at http://sb.cs.cmu.edu/smarts/. CONTACT zivbj@cs.cmu.edu SUPPLEMENTARY INFORMATION Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Aaron Wise
- Lane Center for Computational Biology and Machine Learning Department, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Ziv Bar-Joseph
- Lane Center for Computational Biology and Machine Learning Department, Carnegie Mellon University, Pittsburgh, PA, USA Lane Center for Computational Biology and Machine Learning Department, Carnegie Mellon University, Pittsburgh, PA, USA
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Gitton Y, Narboux-Nême N, Levi G. Transitory expression of Dlx5 and Dlx6 in maxillary arch epithelial precursors is essential for upper jaw morphogenesis. F1000Res 2013; 2:261. [PMID: 25339984 PMCID: PMC4193393 DOI: 10.12688/f1000research.2-261.v3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/15/2014] [Indexed: 01/23/2023] Open
Abstract
Asymmetric, articulated jaws are characteristic of most vertebrate species; they derive from the first pharyngeal arch (PA1) which generates both maxillary and mandibular components. PA1 is colonized by cranial neural crest cells (CNCCs) which give rise to most bones and tendons of the jaws. The elements formed by different CNCCs contingents are specified by the combinatorial expression of
Dlx genes.
Dlx5 and
Dlx6 are predominantly expressed by mandibular CNCCs. Analysis of the phenotype of
Dlx5 and
Dlx6 double mutant mice has suggested that they are necessary and sufficient to specify mandibular identity. Here, using 3D reconstruction, we show that inactivation of
Dlx5 and
Dlx6 does not only affect the mandibular arch, but results in the simultaneous transformation of mandibular and maxillary skeletal elements which assume a similar morphology with gain of symmetry. As
Dlx5- and
Dlx6-expressing cells are not found in the maxillary bud, we have examined the lineage of
Dlx5-expressing progenitors using an
in vivo genetic approach. We find that a contingent of cells deriving from epithelial precursors transiently expressing
Dlx5 participate in the formation of the maxillary arch. These cells are mostly located in the distal part of the maxillary arch and might derive from its lambdoidal junction with the olfactory pit. Our observations provide the first genetic demonstration of the ‘Hinge and Caps’ model[1]. We support the notion that ‘cap’ signals could originate from epithelial derivatives of
Dlx5-expressing progenitors which migrate and colonize the maxillary arch epithelium. Our results imply that Dlx5 and Dlx6 control upper and lower jaw morphogenesis through different coordinated mechanisms to generate functional, articulated jaws.
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Affiliation(s)
- Yorick Gitton
- Evolution des Régulations Endocriniennes, CNRS, UMR7221, Muséum National d'Histoire Naturelle, Paris, France
| | - Nicolas Narboux-Nême
- Evolution des Régulations Endocriniennes, CNRS, UMR7221, Muséum National d'Histoire Naturelle, Paris, France
| | - Giovanni Levi
- Evolution des Régulations Endocriniennes, CNRS, UMR7221, Muséum National d'Histoire Naturelle, Paris, France
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Zhang Y, Ruest LB. Analysis of neural crest cell fate during cardiovascular development using Cre-activated lacZ/β-galactosidase staining. Methods Mol Biol 2012; 843:125-138. [PMID: 22222527 DOI: 10.1007/978-1-61779-523-7_12] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
It is important to identify the mechanisms regulating cardiovascular development. However, complex genetic tools are often required, including transgenic animals that express the lacZ transgene encoding the β-galactosidase enzyme under the control of a specific promoter or following recombination with the Cre recombinase. The latter can be useful for identifying specific cell populations of the developing cardiovascular system, including neural crest cells. The tracking of these cells can help clarify their fate in mutant embryos and elucidate the etiology of some congenital cardiovascular birth defects. This chapter highlights the methods used to stain embryonic tissues in whole mount or sections to detect the expression of the lacZ transgene with a focus on tracking cardiac neural crest cells using the Wnt1-Cre and R26R mouse lines. We also provide a protocol using fluorescence-activated cell sorting for collecting neural crest cells for further analysis. These protocols can be used with any embryos expressing Cre and lacZ.
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Affiliation(s)
- Yanping Zhang
- Department of Biomedical Sciences, Texas A&M Healthy Science Center-Baylor College of Dentistry, Dallas, TX, USA
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Barron F, Woods C, Kuhn K, Bishop J, Howard MJ, Clouthier DE. Downregulation of Dlx5 and Dlx6 expression by Hand2 is essential for initiation of tongue morphogenesis. Development 2011; 138:2249-59. [PMID: 21558373 DOI: 10.1242/dev.056929] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Lower jaw development is a complex process in which multiple signaling cascades establish a proximal-distal organization. These cascades are regulated both spatially and temporally and are constantly refined through both induction of normal signals and inhibition of inappropriate signals. The connective tissue of the tongue arises from cranial neural crest cell-derived ectomesenchyme within the mandibular portion of the first pharyngeal arch and is likely to be impacted by this signaling. Although the developmental mechanisms behind later aspects of tongue development, including innervation and taste acquisition, have been elucidated, the early patterning signals driving ectomesenchyme into a tongue lineage are largely unknown. We show here that the basic helix-loop-helix transcription factor Hand2 plays key roles in establishing the proximal-distal patterning of the mouse lower jaw, in part through establishing a negative-feedback loop in which Hand2 represses Dlx5 and Dlx6 expression in the distal arch ectomesenchyme following Dlx5- and Dlx6-mediated induction of Hand2 expression in the same region. Failure to repress distal Dlx5 and Dlx6 expression results in upregulation of Runx2 expression in the mandibular arch and the subsequent formation of aberrant bone in the lower jaw along with proximal-distal duplications. In addition, there is an absence of lateral lingual swelling expansion, from which the tongue arises, resulting in aglossia. Hand2 thus appears to establish a distal mandibular arch domain that is conducive for lower jaw development, including the initiation of tongue mesenchyme morphogenesis.
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Affiliation(s)
- Francie Barron
- Department of Craniofacial Biology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA
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17
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Jaw muscularization requires Dlx expression by cranial neural crest cells. Proc Natl Acad Sci U S A 2010; 107:11441-6. [PMID: 20534536 DOI: 10.1073/pnas.1001582107] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The origin of active predation in vertebrates is associated with the rise of three major, uniquely derived developmental characteristics of the head: (i) migratory cranial neural crest cells (CNCCs) giving rise to most skeletal skull elements; (ii) expression of Dlx genes by CNCCs in the Hox-free first pharyngeal arch (PA1); and (iii) muscularization of PA1 derivatives. Here we show that these three innovations are tightly linked. Expression of Dlx genes by CNCCs is not only necessary for head skeletogenesis, but also for the determination, differentiation, and patterning of cephalic myogenic mesoderm leading to masticatory muscle formation. In particular, inactivation of Dlx5 and Dlx6 in the mouse results in loss of jaw muscles. As Dlx5/6 are not expressed by the myogenic mesoderm, our findings imply an instructive role for Dlx5/6-positive CNCCs in muscle formation. The defect in muscularization does not result from the loss of mandibular identity observed in Dlx5/6(-/-) mice because masticatory muscles are still present in EdnRA(-/-) mutants, which display a similar jaw transformation. The genesis of jaws and their muscularization should therefore be seen as an integrated Dlx-dependent developmental process at the origin of the vertebrate head. The role of Dlx genes in defining gnathostome jaw identity could, therefore, be secondary to a more primitive function in the genesis of the oral skeletomuscular system.
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Verzi MP, Agarwal P, Brown C, McCulley DJ, Schwarz JJ, Black BL. The transcription factor MEF2C is required for craniofacial development. Dev Cell 2007; 12:645-52. [PMID: 17420000 PMCID: PMC1920108 DOI: 10.1016/j.devcel.2007.03.007] [Citation(s) in RCA: 99] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 02/14/2007] [Accepted: 03/08/2007] [Indexed: 10/23/2022]
Abstract
MEF2 transcription factors are well-established regulators of muscle development. We have discovered an unanticipated role for MEF2C in the neural crest, where tissue-specific inactivation results in neonatal lethality due to severe craniofacial defects. We show that MEF2C is required for expression of the Dlx5, Dlx6, and Hand2 transcription factor genes in the branchial arches, and we identify a branchial arch-specific enhancer in the Dlx5/6 locus, which is activated synergistically by MEF2C and Dlx5, demonstrating that these factors interact to induce transcription. Mef2c and Dlx5/6 also interact genetically. Mice heterozygous for either Dlx5/6 or Mef2c are normal at birth and survive to weaning. By contrast, heterozygosity for both Mef2c and Dlx5/6 results in defective palate development and neonatal lethality. Taken together, the studies presented here define a feed-forward transcriptional circuit between the MADS-box transcription factor MEF2C and the homeodomain transcription factors Dlx5 and Dlx6 in craniofacial development.
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Affiliation(s)
- Michael P. Verzi
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, Mail Code 2240, University of California, San Francisco, California 94158-2517 USA
| | - Pooja Agarwal
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, Mail Code 2240, University of California, San Francisco, California 94158-2517 USA
| | - Courtney Brown
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, Mail Code 2240, University of California, San Francisco, California 94158-2517 USA
| | - David J. McCulley
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, Mail Code 2240, University of California, San Francisco, California 94158-2517 USA
| | - John J. Schwarz
- Center for Cardiovascular Sciences, Albany Medical Center, Albany, NY 12208 USA
| | - Brian L. Black
- Cardiovascular Research Institute and Department of Biochemistry and Biophysics, Mail Code 2240, University of California, San Francisco, California 94158-2517 USA
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Abstract
The G-protein-coupled receptor signaling system, consisting of a huge variety of receptors as well as of many G-proteins and effectors, operates in every cell and is involved in many physiological and pathological processes. The versatility of this system and the involvement of specific components makes G-protein-coupled receptors and their signaling pathways ideal targets for pharmacological interventions. Classical mouse knockout models have often provided important preliminary insights into the biological roles of individual receptors and signaling pathways and they are routinely used in the process of target validation. The recent development of efficient conditional mutagenesis techniques now allows a much more detailed analysis of G-protein-mediated signaling transduction processes. This review summarizes some of the areas in which progress has recently been made by applying conditional mutagenesis of genes coding for G-proteins and G-protein-coupled receptors.
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Affiliation(s)
- S Offermanns
- Institute of Pharmacology, University of Heidelberg, Im Neuenheimer Feld 366, 69120 Heidelberg, Germany.
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20
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Abstract
Explorations into the molecular embryology of the mouse have played a vital role in our understanding of the basic mechanisms of gene regulation that govern development and disease. In the last 15 years, these mechanisms have been analyzed with vastly greater precision and clarity with the advent of systems that allow the conditional control of gene expression. Typically, this control is achieved by silencing or activating the gene of interest with site-specific DNA recombination or transcriptional transactivation. In this review, I discuss the application of these technologies to mouse development, focusing on recent innovations and experimental designs that specifically aid the study of the mouse embryo.
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Affiliation(s)
- M Lewandoski
- Laboratory of Cancer and Developmental Biology, NCI-Frederick, National Institutes of Health, Frederick, MD 21702-1201, USA.
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21
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Richman JM, Buchtová M, Boughner JC. Comparative ontogeny and phylogeny of the upper jaw skeleton in amniotes. Dev Dyn 2006; 235:1230-43. [PMID: 16496291 DOI: 10.1002/dvdy.20716] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The morphology, position, and presence of the upper jaw bones vary greatly across amniote taxa. In this review, we compare the development and anatomy of upper jaw bones from the three living amniote groups: reptiles, birds, and mammals. The study of reptiles is particularly important as comparatively little is known about the embryogenesis of the jaw in this group. Our review covers the ontogeny and phylogeny of membranous bones in the face. The aim is to identify conserved embryonic processes that may exist among the three major amniote groups. Finally, we discuss how temporal and spatial regulation of preosseous condensations and ossification centers can lead to variation in the morphology of amniote upper jaw bones.
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Affiliation(s)
- Joy M Richman
- Cellular Mechanisms of Development Group and Department of Oral Health Sciences, Life Sciences Institute, University of British Columbia, Vancouver, B.C., Canada.
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22
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Bogush AI, McCarthy LE, Tian C, Olm V, Gieringer T, Ivkovic S, Ehrlich ME. DARPP-32 genomic fragments drive Cre expression in postnatal striatum. Genesis 2005; 42:37-46. [PMID: 15830379 DOI: 10.1002/gene.20118] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
To direct Cre-mediated recombination to differentiated medium-size spiny neurons (MSNs) of the striatum, we generated transgenic mice that express Cre recombinase under the regulation of DARPP-32 genomic fragments. In this reported line, recombination of an R26R reporter allele occurred postnatally in the majority of medium-size spiny neurons of the dorsal and ventral striatum (caudate nucleus and nucleus accumbens/olfactory tubercle), as well as in the piriform cortex and choroid plexus. Although regulatory fragments were selected to target MSNs, low levels of Cre-recombinase expression, as detected by beta-galactosidase activity from the R26R reporter gene, were also apparent in widely dispersed areas or cells of the forebrain and hindbrain. These included the primary and secondary motor cortex, and association cortex, as well as in the olfactory bulb and cerebellar Purkinje cells. Notably, expression in these regions was well below that of endogenous DARPP-32. Analysis of colocalization of beta-galactosidase, as detected either by histochemistry or immunocytochemistry, and DARPP-32 revealed double-labeling in almost all DARPP-32-expressing MSNs in the postnatal striatum, but not in extrastriatal regions. The DARPP-32Cre transgenic mouse line thus provides a useful tool to specifically express and/or inactivate genes in mature MSNs of the striatum.
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Affiliation(s)
- Alexey I Bogush
- Farber Institute for Neurosciences, Thomas Jefferson University College of Medicine, Philadelphia, Pennsylvania 19107-5099, USA
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Ruest LB, Kedzierski R, Yanagisawa M, Clouthier DE. Deletion of the endothelin-A receptor gene within the developing mandible. Cell Tissue Res 2005; 319:447-53. [PMID: 15647918 PMCID: PMC2806232 DOI: 10.1007/s00441-004-0988-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2004] [Accepted: 08/09/2004] [Indexed: 12/01/2022]
Abstract
Signaling from the endothelin-A (Ednra) receptor is responsible for initiating multiple signaling pathways within neural crest cells (NCCs). Loss of this initiation is presumably the basis for the craniofacial defects observed in Ednra-/- embryos. However, it is not known whether continued Ednra signaling in NCC derivatives is required for subsequent development of the lower jaw. To address this question, mice containing loxP recombination sequences flanking a portion of the Ednra gene were bred with transgenic mice that express Cre recombinase under control of a Dlx5/6 enhancer element. We find that while Ednra gene inactivation within the mandibular arch of these Ednra conditional knockout embryos is detectable by embryonic day (E) 10.5, mandibular arch-specific gene expression is normal, as is overall mandible development. These results suggest that while Ednra receptor signaling is crucial for early NCC patterning, subsequent Ednra signaling is not essential for mandible bone development.
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Affiliation(s)
- Louis-Bruno Ruest
- Department of Molecular, Cellular and Craniofacial Biology and the Birth Defects Center, University of Louisville, Louisville, KY, 40292, USA
| | - Rafal Kedzierski
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - Masashi Yanagisawa
- Department of Molecular Genetics, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
- Howard Hughes Medical Institute, University of Texas Southwestern Medical Center, Dallas, TX, 75390, USA
| | - David E. Clouthier
- Department of Molecular, Cellular and Craniofacial Biology and the Birth Defects Center, University of Louisville, Louisville, KY, 40292, USA, , Tel.: +1-502-8522452, Fax: +1-502-8524702
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