1
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Singh M, Spendlove SJ, Wei A, Bondhus LM, Nava AA, de L Vitorino FN, Amano S, Lee J, Echeverria G, Gomez D, Garcia BA, Arboleda VA. KAT6A mutations in Arboleda-Tham syndrome drive epigenetic regulation of posterior HOXC cluster. Hum Genet 2023; 142:1705-1720. [PMID: 37861717 PMCID: PMC10676314 DOI: 10.1007/s00439-023-02608-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 09/28/2023] [Indexed: 10/21/2023]
Abstract
Arboleda-Tham Syndrome (ARTHS) is a rare genetic disorder caused by heterozygous, de novo mutations in Lysine(K) acetyltransferase 6A (KAT6A). ARTHS is clinically heterogeneous and characterized by several common features, including intellectual disability, developmental and speech delay, and hypotonia, and affects multiple organ systems. KAT6A is the enzymatic core of a histone-acetylation protein complex; however, the direct histone targets and gene regulatory effects remain unknown. In this study, we use ARTHS patient (n = 8) and control (n = 14) dermal fibroblasts and perform comprehensive profiling of the epigenome and transcriptome caused by KAT6A mutations. We identified differential chromatin accessibility within the promoter or gene body of 23% (14/60) of genes that were differentially expressed between ARTHS and controls. Within fibroblasts, we show a distinct set of genes from the posterior HOXC gene cluster (HOXC10, HOXC11, HOXC-AS3, HOXC-AS2, and HOTAIR) that are overexpressed in ARTHS and are transcription factors critical for early development body segment patterning. The genomic loci harboring HOXC genes are epigenetically regulated with increased chromatin accessibility, high levels of H3K23ac, and increased gene-body DNA methylation compared to controls, all of which are consistent with transcriptomic overexpression. Finally, we used unbiased proteomic mass spectrometry and identified two new histone post-translational modifications (PTMs) that are disrupted in ARTHS: H2A and H3K56 acetylation. Our multi-omics assays have identified novel histone and gene regulatory roles of KAT6A in a large group of ARTHS patients harboring diverse pathogenic mutations. This work provides insight into the role of KAT6A on the epigenomic regulation in somatic cell types.
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Affiliation(s)
- Meghna Singh
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Sarah J Spendlove
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Interdepartmental BioInformatics Program, UCLA, Los Angeles, CA, USA
| | - Angela Wei
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Interdepartmental BioInformatics Program, UCLA, Los Angeles, CA, USA
| | - Leroy M Bondhus
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Aileen A Nava
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Francisca N de L Vitorino
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, St. Louis, MO, USA
| | - Seth Amano
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Jacob Lee
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Gesenia Echeverria
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Dianne Gomez
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA
| | - Benjamin A Garcia
- Department of Biochemistry and Molecular Biophysics, Washington University in St. Louis, St. Louis, MO, USA
| | - Valerie A Arboleda
- Department of Pathology and Laboratory Medicine, David Geffen School of Medicine, UCLA, 615 Charles E. Young Drive South, Los Angeles, CA, 90095, USA.
- Department of Human Genetics, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.
- Department of Computational Medicine, David Geffen School of Medicine, UCLA, Los Angeles, CA, USA.
- Interdepartmental BioInformatics Program, UCLA, Los Angeles, CA, USA.
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2
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Lee Y, Yeo IS, Kim N, Lee DK, Kim KT, Yoon J, Yi J, Hong YB, Choi BO, Kosodo Y, Kim D, Park J, Song MR. Transcriptional control of motor pool formation and motor circuit connectivity by the LIM-HD protein Isl2. eLife 2023; 12:e84596. [PMID: 37869988 PMCID: PMC10637776 DOI: 10.7554/elife.84596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 10/11/2023] [Indexed: 10/24/2023] Open
Abstract
The fidelity of motor control requires the precise positional arrangement of motor pools and the establishment of synaptic connections between them. During neural development in the spinal cord, motor nerves project to specific target muscles and receive proprioceptive input from these muscles via the sensorimotor circuit. LIM-homeodomain transcription factors are known to play a crucial role in successively restricting specific motor neuronal fates. However, their exact contribution to limb-based motor pools and locomotor circuits has not been fully understood. To address this, we conducted an investigation into the role of Isl2, a LIM-homeodomain transcription factor, in motor pool organization. We found that deletion of Isl2 led to the dispersion of motor pools, primarily affecting the median motor column (MMC) and lateral motor column (LMC) populations. Additionally, hindlimb motor pools lacked Etv4 expression, and we observed reduced terminal axon branching and disorganized neuromuscular junctions in Isl2-deficient mice. Furthermore, we performed transcriptomic analysis on the spinal cords of Isl2-deficient mice and identified a variety of downregulated genes associated with motor neuron (MN) differentiation, axon development, and synapse organization in hindlimb motor pools. As a consequence of these disruptions, sensorimotor connectivity and hindlimb locomotion were impaired in Isl2-deficient mice. Taken together, our findings highlight the critical role of Isl2 in organizing motor pool position and sensorimotor circuits in hindlimb motor pools. This research provides valuable insights into the molecular mechanisms governing motor control and its potential implications for understanding motor-related disorders in humans.
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Affiliation(s)
- Yunjeong Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - In Seo Yeo
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - Namhee Kim
- Fermentation Regulation Technology Research Group, World Institute of KimchiGwangjuRepublic of Korea
| | - Dong-Keun Lee
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - Kyung-Tai Kim
- Jeonbuk Department of Inhalation Research, Korea Institute of ToxicologyJeongeup-siRepublic of Korea
| | - Jiyoung Yoon
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - Jawoon Yi
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - Young Bin Hong
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of MedicineSeoulRepublic of Korea
- Department of Biochemistry, College of Medicine, Dong-A UniversityBusanRepublic of Korea
| | - Byung-Ok Choi
- Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of MedicineSeoulRepublic of Korea
| | - Yoichi Kosodo
- Korea Brain Research InstituteDaeguRepublic of Korea
| | - Daesoo Kim
- Department of Brain and Cognitive Sciences, Korea Advanced Institute of Science and Technology (KAIST)DaejeonRepublic of Korea
| | - Jihwan Park
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
| | - Mi-Ryoung Song
- School of Life Sciences, Gwangju Institute of Science and Technology, Oryong-dong, Buk-guGwangjuRepublic of Korea
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Holtz MA, Racicot R, Preininger D, Stuckert AMM, Mangiamele LA. Genome assembly of the foot-flagging frog, Staurois parvus: a resource for understanding mechanisms of behavior. G3 (BETHESDA, MD.) 2023; 13:jkad193. [PMID: 37625789 PMCID: PMC10542557 DOI: 10.1093/g3journal/jkad193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 03/22/2023] [Accepted: 08/13/2023] [Indexed: 08/27/2023]
Abstract
Elaborate and skilled movements of the body have been selected in a variety of species as courtship and rivalry signals. One roadblock in studying these behaviors has been a lack of resources for understanding how they evolved at the genetic level. The Bornean rock frog (Staurois parvus) is an ideal species in which to address this issue. Males wave their hindlimbs in a "foot-flagging" display when competing for mates. The evolution of foot flagging in S. parvus and other species is accompanied by increases in the expression of the androgen receptor gene within its neuromuscular system, but it remains unclear what genetic or transcriptional changes are associated with this behavioral phenotype. We have now assembled the genome of S. parvus, resulting in 3.98 Gbp of 22,402 contigs with an N50 of 611,229 bp. The genome will be a resource for finding genes related to the physiology underlying foot flagging and to adaptations of the neuromuscular system. As a first application of the genome, we also began work in comparative genomics and differential gene expression analysis. We show that the androgen receptor is diverged from other anuran species, and we identify unique expression patterns of genes in the spinal cord and leg muscle that are important for axial patterning, cell specification and morphology, or muscle contraction. This genome will continue to be an important tool for future -omics studies to understand the evolution of elaborate signaling behaviors in this and potentially related species.
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Affiliation(s)
- Mika A Holtz
- Department of Biological Sciences, Smith College, Northampton, MA 01053, USA
| | - Riccardo Racicot
- Department of Biological Sciences, Smith College, Northampton, MA 01053, USA
| | - Doris Preininger
- Vienna Zoo, 1130 Vienna, Austria
- Department of Evolutionary Biology, University of Vienna, 1030 Vienna, Austria
| | - Adam M M Stuckert
- Department of Biology & Biochemistry, University of Houston, Houston, TX 77204, USA
| | - Lisa A Mangiamele
- Department of Biological Sciences, Smith College, Northampton, MA 01053, USA
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4
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Zilliox MJ, Foecking EM, Kuffel GR, Conneely M, Saban KL, Herrold AA, Kletzel SL, Radke JR, Walsh E, Guernon A, Pape A, Ripley DL, Patil V, Pacheco MS, Rosenow JM, Bhaumik R, Bhaumik D, Pape TLB. An Initial miRNA Profile of Persons With Persisting Neurobehavioral Impairments and States of Disordered Consciousness After Severe Traumatic Brain Injury. J Head Trauma Rehabil 2023; 38:E267-E277. [PMID: 36350037 DOI: 10.1097/htr.0000000000000821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVE To examine the merits of using microRNAs (miRNAs) as biomarkers of disorders of consciousness (DoC) due to traumatic brain injury (TBI). SETTINGS Acute and subacute beds. PARTICIPANTS Patients remaining in vegetative and minimally conscious states (VS, MCS), an average of 1.5 years after TBI, and enrolled in a randomized clinical trial ( n = 6). Persons without a diagnosed central nervous system disorder, neurotypical controls ( n = 5). DESIGN Comparison of whole blood miRNA profiles between patients and age/gender-matched controls. For patients, correlational analyses between miRNA profiles and measures of neurobehavioral function. MAIN MEASURES Baseline measures of whole blood miRNAs isolated from the cellular and fluid components of blood and measured using miRNA-seq and real-time polymerase chain reaction (RT-PCR). Baseline neurobehavioral measures derived from 7 tests. RESULTS For patients, relative to controls, 48 miRNA were significantly ( P < .05)/differentially expressed. Cluster analysis showed that neurotypical controls were most similar to each other and with 2 patients (VS: n = 1; and MCS: n = 1). Three patients, all in MCS, clustered separately. The only female in the sample, also in MCS, formed an independent group. For the 48 miRNAs, the enriched pathways identified are implicated in secondary brain damage and 26 miRNAs were significantly ( P < .05) correlated with measures of neurobehavioral function. CONCLUSIONS Patients remaining in states of DoC an average of 1.5 years after TBI showed a different and reproducible pattern of miRNA expression relative to age/gender-matched neurotypical controls. The phenotypes, defined by miRNA profiles relative to persisting neurobehavioral impairments, provide the basis for future research to determine the miRNA profiles differentiating states of DoC and the basis for future research using miRNA to detect treatment effects, predict treatment responsiveness, and developing targeted interventions. If future research confirms and advances reported findings, then miRNA profiles will provide the foundation for patient-centric DoC neurorehabilitation.
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Affiliation(s)
- Michael J Zilliox
- Department of Ophthalmology, Loyola University Medical Center, Maywood, Illinois (Dr Zilliox); Research and Development Service (Drs Foecking, Walsh, Guernon, and Bender Pape), Center for Innovation in Complex Chronic Healthcare & Research Service (Drs Saban, Herrold, Kletzel, and Bender Pape), Rehabilitation Service (Dr Pacheco), and Department of Neurology (Dr Patil), Edward Hines Jr VA Hospital, Hines, Illinois; Department of Otolaryngology-Head and Neck Surgery (Dr Foecking), Marcella Niehoff School of Nursing (Dr Saban), Infectious Diseases and Immunology Research Institute (Dr Radke), and Division of Infectious Diseases (Dr Radke), Loyola University Chicago, Maywood, Illinois; Loyola Genomics Facility, Loyola University, Maywood, Illinois (Ms Kuffel); Chicago Medical School, Rosalind Franklin University of Science and Medicine, North Chicago, Illinois (Dr Conneely); Departments of Psychiatry & Behavioral Sciences (Dr Herrold), Physical Medicine and Rehabilitation (Drs Ripley and Bender Pape), and Neurosurgery (Dr Rosenow), Northwestern University, Feinberg School of Medicine, Chicago, Illinois; Department of Laboratory Medicine and Pathology, University of Washington Medicine, Seattle (Dr Pape); Lewis University, College of Nursing and Health Sciences, Romeoville, Illinois (Dr Guernon); Department of Psychiatry, Biostatistical Research Center, Division of Epidemiology and Biostatistics (Drs R. Bhaumik and D. Bhaumik), University of Illinois at Chicago; HealthBridge, Arlington Heights, Illinois (Dr Ripley); Dr Radke is now at Research Section, Boise VA Hospital, Boise, Idaho; Ms Kuffel is now at National Institutes of Health, Bethesda, Maryland
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5
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Abstract
Hox genes encode evolutionarily conserved transcription factors that are essential for the proper development of bilaterian organisms. Hox genes are unique because they are spatially and temporally regulated during development in a manner that is dictated by their tightly linked genomic organization. Although their genetic function during embryonic development has been interrogated, less is known about how these transcription factors regulate downstream genes to direct morphogenetic events. Moreover, the continued expression and function of Hox genes at postnatal and adult stages highlights crucial roles for these genes throughout the life of an organism. Here, we provide an overview of Hox genes, highlighting their evolutionary history, their unique genomic organization and how this impacts the regulation of their expression, what is known about their protein structure, and their deployment in development and beyond.
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Affiliation(s)
- Katharine A. Hubert
- Program in Genetics, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
| | - Deneen M. Wellik
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, Madison, WI 53705, USA
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6
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Wu K, Liu Z, Dong C, Gu S, Li L, Wang W, Zhou Y. MiR-4739 inhibits the malignant behavior of esophageal squamous cell carcinoma cells via the homeobox C10/vascular endothelial growth factor A/phosphatidylinositol 3-kinase/AKT pathway. Bioengineered 2022; 13:14066-14079. [PMID: 35730500 PMCID: PMC9342426 DOI: 10.1080/21655979.2022.2068783] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Esophageal cancer is a lethal disease, and emerging evidence has shown that microRNAs are involved in its development, progression, and clinical outcome. MicroRNAs are potential biomarkers for esophageal squamous cell carcinoma (ESCC), and may be useful in advanced RNA therapy for ESCC. This study was conducted to evaluate the molecular mechanism of miR-4739 in ESCC. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to measure RNA and protein levels. Transwell assay, Cell Counting Kit-8 assay, cytometry analysis, and human umbilical vein endothelial cell tube formation assay were conducted to determine the molecular function of miR-4739 in ESCC. Potential targets of miR-4739 were predicted using bioinformatics tools and confirmed in ESCC cells using a luciferase reporter and RNA pulldown assay. Finally, we performed immunohistochemistry to evaluate the effects of administering agomir-4739 to a mouse model of ESCC. MiR-4739 expression was downregulated in ESCC tissues and cells. MiR-4739 overexpression inhibited cell proliferation, migration, and invasion, and promoted apoptosis of ESCC cells. Furthermore, vascular endothelial growth factor A expression was downregulated by miR-4739 mimics in ESCC cells. MiR-4739 negatively regulated homeobox C10 expression. Additionally, agomir-4739 inhibited tumor growth and angiogenesis in vivo. We demonstrated that miR-4739 overexpression exerted an inhibitory effect on ESCC cells by preventing the expression of homeobox C10 via the vascular endothelial growth factor A/phosphatidylinositol 3-kinase/AKT pathway, indicating the potential of this microRNA as a treatment target in ESCC.
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Affiliation(s)
- Kaiqin Wu
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Zhenchuan Liu
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Chenglai Dong
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Shaorui Gu
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Lei Li
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Wenli Wang
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
| | - Yongxin Zhou
- Department of Thoracic-Cardiovascular Surgery, Tongji Hospital, School of Medicine, Tongji University, Shanghai, Jiangsu, China
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7
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Needham J, Metzis V. Heads or tails: Making the spinal cord. Dev Biol 2022; 485:80-92. [DOI: 10.1016/j.ydbio.2022.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/15/2021] [Accepted: 03/02/2022] [Indexed: 12/14/2022]
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8
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Joshi R, Sipani R, Bakshi A. Roles of Drosophila Hox Genes in the Assembly of Neuromuscular Networks and Behavior. Front Cell Dev Biol 2022; 9:786993. [PMID: 35071230 PMCID: PMC8777297 DOI: 10.3389/fcell.2021.786993] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/14/2021] [Indexed: 11/13/2022] Open
Abstract
Hox genes have been known for specifying the anterior-posterior axis (AP) in bilaterian body plans. Studies in vertebrates have shown their importance in developing region-specific neural circuitry and diversifying motor neuron pools. In Drosophila, they are instrumental for segment-specific neurogenesis and myogenesis early in development. Their robust expression in differentiated neurons implied their role in assembling region-specific neuromuscular networks. In the last decade, studies in Drosophila have unequivocally established that Hox genes go beyond their conventional functions of generating cellular diversity along the AP axis of the developing central nervous system. These roles range from establishing and maintaining the neuromuscular networks to controlling their function by regulating the motor neuron morphology and neurophysiology, thereby directly impacting the behavior. Here we summarize the limited knowledge on the role of Drosophila Hox genes in the assembly of region-specific neuromuscular networks and their effect on associated behavior.
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Affiliation(s)
- Rohit Joshi
- Laboratory of Drosophila Neural Development, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad, India
| | - Rashmi Sipani
- Laboratory of Drosophila Neural Development, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad, India.,Graduate Studies, Manipal Academy of Higher Education, Manipal, India
| | - Asif Bakshi
- Laboratory of Drosophila Neural Development, Centre for DNA Fingerprinting and Diagnostics (CDFD), Hyderabad, India.,Graduate Studies, Manipal Academy of Higher Education, Manipal, India
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9
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Dasen JS. Establishing the Molecular and Functional Diversity of Spinal Motoneurons. ADVANCES IN NEUROBIOLOGY 2022; 28:3-44. [PMID: 36066819 DOI: 10.1007/978-3-031-07167-6_1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Spinal motoneurons are a remarkably diverse class of neurons responsible for facilitating a broad range of motor behaviors and autonomic functions. Studies of motoneuron differentiation have provided fundamental insights into the developmental mechanisms of neuronal diversification, and have illuminated principles of neural fate specification that operate throughout the central nervous system. Because of their relative anatomical simplicity and accessibility, motoneurons have provided a tractable model system to address multiple facets of neural development, including early patterning, neuronal migration, axon guidance, and synaptic specificity. Beyond their roles in providing direct communication between central circuits and muscle, recent studies have revealed that motoneuron subtype-specific programs also play important roles in determining the central connectivity and function of motor circuits. Cross-species comparative analyses have provided novel insights into how evolutionary changes in subtype specification programs may have contributed to adaptive changes in locomotor behaviors. This chapter focusses on the gene regulatory networks governing spinal motoneuron specification, and how studies of spinal motoneurons have informed our understanding of the basic mechanisms of neuronal specification and spinal circuit assembly.
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Affiliation(s)
- Jeremy S Dasen
- NYU Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY, USA.
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10
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Chen Z, Wu J, Liu B, Zhang G, Wang Z, Zhang L, Wang K, Fan Z, Zhu P. Identification of cis-HOX-HOXC10 axis as a therapeutic target for colorectal tumor-initiating cells without APC mutations. Cell Rep 2021; 36:109431. [PMID: 34320348 DOI: 10.1016/j.celrep.2021.109431] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 05/17/2021] [Accepted: 06/30/2021] [Indexed: 01/15/2023] Open
Abstract
Colorectal cancer (CRC) is one of the most common cancers worldwide, in which adenomatous polyposis coli (APC) mutations are frequently and uniquely observed. Here we find that cis-HOX (circular RNA stabilizing HOXC10) is robustly expressed in colorectal tumor-initiating cells (TICs). cis-HOX knockout decreases colorectal TIC numbers and impairs the self-renewal, tumorigenesis, and metastatic capacities of TICs, whereas cis-HOX overexpression drives colorectal TIC self-renewal and metastasis. Mechanistically, cis-HOX binds to HOXC10 mRNA to attenuate its decay through blocking the K-homology splicing regulatory protein (KSRP)-binding sequence of HOXC10 3' UTR. HOXC10 is highly expressed in colorectal tumors and TICs and triggers Wnt/β-catenin activation by activating FZD3 expression. HOXC10 inhibitor salinomycin exerts efficient therapeutic effects in APC-wild-type colorectal tumors, but not in tumors with APC nonsense mutations. Therefore, the cis-HOX-HOXC10 pathway drives colorectal tumorigenesis, stemness, and metastasis and serves as a potential therapeutic target for APC-wild-type colorectal tumors.
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Affiliation(s)
- Zhenzhen Chen
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; International Joint Laboratory for Protein and Peptide Drugs of Henan Province, Zhengzhou 450001, China.
| | - Jiayi Wu
- School of Medicine, Nankai University, 94 Weijin Road, Tianjin 300071, China
| | - Benyu Liu
- Research Center of Basic Medicine, Academy of Medical Sciences, Zhengzhou University, Zhengzhou, Henan, China; CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
| | - Guangtan Zhang
- Department of Gastrointestinal Surgery, Henan Provincial People's Hospital, People's Hospital of Henan University, People's Hospital of Zhengzhou University, No. 7 Weiwu Road, Zhengzhou, Henan Province 450003, China
| | - Zhiwei Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Lulu Zhang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Kaili Wang
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China
| | - Zusen Fan
- CAS Key Laboratory of Infection and Immunity, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China.
| | - Pingping Zhu
- School of Life Sciences, Zhengzhou University, Zhengzhou 450001, China; State Key Laboratory of Esophageal Cancer Prevention & Treatment, Zhengzhou University, Zhengzhou, Henan Province 450052, China.
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11
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Priyanka P, Sharma M, Das S, Saxena S. The lncRNA HMS recruits RNA-binding protein HuR to stabilize the 3'-UTR of HOXC10 mRNA. J Biol Chem 2021; 297:100997. [PMID: 34302808 PMCID: PMC8363838 DOI: 10.1016/j.jbc.2021.100997] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 07/09/2021] [Accepted: 07/19/2021] [Indexed: 12/27/2022] Open
Abstract
Long noncoding RNAs (lncRNAs) have been reported to drive key cancer pathways but the functions of majority of lncRNAs are unknown making a case for comprehensive functional evaluation of lncRNAs. With an aim to identify lncRNAs dysregulated in human cancers, we analyzed the cancer patient database of lung adenocarcinoma (LUAD), which revealed an upregulated lncRNA, LINC02381 (renamed HOXC10mRNA stabilizing factor or HMS in this study), whose depletion results in proliferation defects and inhibition of colony formation of human cancer cells. In order to identify the binding targets of HMS, we screened for cis-genes and discovered that HOXC10, an oncogene, is downregulated in the absence of HMS. Depletion of HMS does not affect the HOXC10 promoter activity but inhibits the HOXC10 3′-UTR-linked luciferase reporter activity. Since lncRNAs have been known to associate with RNA-binding proteins (RBPs) to stabilize mRNA transcripts, we screened for different RBPs and discovered that HuR, an ELAV family protein, stabilizes HOXC10 mRNA. Using RNA pull-down and deletion mapping experiments, we show that HuR physically interacts with the cytosine-rich stretch of HMS and HOXC10 3′-UTR to stabilize HOXC10 mRNA. HOXC10 is overexpressed in many human cancers, and our discovery highlights that lncRNA HMS sustains the HOXC10 mRNA levels to maintain the invasive phenotypes of cancer cells.
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Affiliation(s)
- Priyanka Priyanka
- DNA Replication and Cell Cycle Laboratory, National Institute of Immunology, New Delhi, India
| | | | - Sanjeev Das
- DNA Replication and Cell Cycle Laboratory, National Institute of Immunology, New Delhi, India
| | - Sandeep Saxena
- DNA Replication and Cell Cycle Laboratory, National Institute of Immunology, New Delhi, India; Department of Biotechnology, JNU, New Delhi, India.
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12
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RNA-sequence reveals differentially expressed genes affecting the crested trait of Wumeng crested chicken. Poult Sci 2021; 100:101357. [PMID: 34329989 PMCID: PMC8335650 DOI: 10.1016/j.psj.2021.101357] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 06/22/2021] [Indexed: 12/12/2022] Open
Abstract
Wumeng crested chicken has a cluster of slender feathers on its head, and the underlying skull region exhibits an obvious tumor-like protrusion. This is the typical skull structure of crested chickens. The associated regulatory genes are located on autosomes and are incompletely dominant. This trait is related to brain herniation, but the genetic mechanisms of its formation and development are unclear. In this study, RNA sequencing (RNA-Seq) analysis was conducted on 6 skull tissue samples from 3 Wumeng crested chickens with prominent skull protrusions and 3 without a prominent skull protrusion phenotype. A total of 46,376,934 to 43,729,046 clean reads were obtained, the percentage of uniquely mapped reads compared with the reference genome was between 89.73%-91.00%, and 39,795,458-41,836,502 unique reads were obtained. Among different genomic regions, the highest frequency of sequencing reads occurred in exon regions (85.44-88.28%). Additionally, a total of 423 new transcripts and 26,999 alternative splicings (AS) events were discovered in this sequencing analysis. This study identified 1,089 differentially expressed genes (DEGs), among which 485 were upregulated and 604 were downregulated. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses indicated that the DEGs were enriched in terms related to signal transduction, cell development, cell differentiation, the lysosome, serine, and threonine metabolism, and the interaction of cytokines with cytokine receptors. Based on the comprehensive analysis of DEGs combined with reported quantitative trait loci (QTLs), the expression of BMP2, EPHA3, EPHB1, HOXC6, SCN2B, BMP7, and HOXC10 was verified by real-time quantitative polymerase chain reaction (qRT-PCR). The qRT-PCR results were consistent with the RNA-Seq results, indicating that these 7 genes may be candidates genes regulating the crested trait.
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13
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Imai F, Adam M, Potter SS, Yoshida Y. HoxD transcription factors define monosynaptic sensory-motor specificity in the developing spinal cord. Development 2021; 148:269156. [PMID: 34128984 DOI: 10.1242/dev.191122] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 05/17/2021] [Indexed: 12/21/2022]
Abstract
The specificity of monosynaptic connections between proprioceptive sensory neurons and their recipient spinal motor neurons depends on multiple factors, including motor neuron positioning and dendrite morphology, axon projection patterns of proprioceptive sensory neurons in the spinal cord, and the ligand-receptor molecules involved in cell-to-cell recognition. However, with few exceptions, the transcription factors engaged in this process are poorly characterized. Here, we show that members of the HoxD family of transcription factors play a crucial role in the specificity of monosynaptic sensory-motor connections. Mice lacking Hoxd9, Hoxd10 and Hoxd11 exhibit defects in locomotion but have no obvious defects in motor neuron positioning or dendrite morphology through the medio-lateral and rostro-caudal axes. However, we found that quadriceps motor neurons in these mice show aberrant axon development and receive inappropriate inputs from proprioceptive sensory axons innervating the obturator muscle. These genetic studies demonstrate that the HoxD transcription factors play an integral role in the synaptic specificity of monosynaptic sensory-motor connections in the developing spinal cord.
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Affiliation(s)
- Fumiyasu Imai
- Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Mike Adam
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - S Steven Potter
- Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
| | - Yutaka Yoshida
- Neural Connectivity Development in Physiology and Disease Laboratory, Burke Neurological Institute, White Plains, NY 10605, USA.,Feil Family Brain and Mind Research Institute, Weill Cornell Medicine, New York, NY 10065, USA.,Division of Developmental Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45229, USA
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14
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Abstract
The HOXC10 gene, a member of the HOX genes family, plays crucial roles in mammalian physiological processes, such as limb morphological development, limb regeneration, and lumbar motor neuron differentiation. HOXC10 is also associated with angiogenesis, fat metabolism, and sex regulation. Additional evidence suggests that HOXC10 dysregulation is closely associated with various tumors. HOXC10 is an important transcription factor that can activate several oncogenic pathways by regulating various target molecules such as ERK, AKT, p65, and epithelial mesenchymal transition-related genes. HOXC10 also induces drug resistance in cancers by promoting the DNA repair pathway. In this review, we summarize HOXC10 gene structure and expression as well as the role of HOXC10 in different human cancer processes. This review will provide insight into the status of HOXC10 research and help identify novel targets for cancer therapy.
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Affiliation(s)
- Jinyong Fang
- Department of Science and Education, Jinhua Guangfu Oncology Hospital, Jinhua, China
| | - Jianjun Wang
- Department of Gastroenterological Surgery, Jinhua Guangfu Oncology Hospital, Jinhua, China
| | - Liangliang Yu
- Department of Gastroenterology, Sir Run Run Shaw Hospital, Medical School of Zhejiang University, Hangzhou, China
| | - Wenxia Xu
- Central Laboratory, Affiliated Jinhua Hospital, Zhejiang University School of Medicine, Jinhua, China
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15
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Wang K, Wang J, Zhu C, Yang L, Ren Y, Ruan J, Fan G, Hu J, Xu W, Bi X, Zhu Y, Song Y, Chen H, Ma T, Zhao R, Jiang H, Zhang B, Feng C, Yuan Y, Gan X, Li Y, Zeng H, Liu Q, Zhang Y, Shao F, Hao S, Zhang H, Xu X, Liu X, Wang D, Zhu M, Zhang G, Zhao W, Qiu Q, He S, Wang W. African lungfish genome sheds light on the vertebrate water-to-land transition. Cell 2021; 184:1362-1376.e18. [PMID: 33545087 DOI: 10.1016/j.cell.2021.01.047] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Revised: 11/09/2020] [Accepted: 01/27/2021] [Indexed: 12/26/2022]
Abstract
Lungfishes are the closest extant relatives of tetrapods and preserve ancestral traits linked with the water-to-land transition. However, their huge genome sizes have hindered understanding of this key transition in evolution. Here, we report a 40-Gb chromosome-level assembly of the African lungfish (Protopterus annectens) genome, which is the largest genome assembly ever reported and has a contig and chromosome N50 of 1.60 Mb and 2.81 Gb, respectively. The large size of the lungfish genome is due mainly to retrotransposons. Genes with ultra-long length show similar expression levels to other genes, indicating that lungfishes have evolved high transcription efficacy to keep gene expression balanced. Together with transcriptome and experimental data, we identified potential genes and regulatory elements related to such terrestrial adaptation traits as pulmonary surfactant, anxiolytic ability, pentadactyl limbs, and pharyngeal remodeling. Our results provide insights and key resources for understanding the evolutionary pathway leading from fishes to humans.
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Affiliation(s)
- Kun Wang
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China
| | - Jun Wang
- Joint Laboratory of Guangdong Province and Hong Kong Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou 510642, China; School of Civil Engineering, Architecture and Environment, Hubei University of Technology, Wuhan 430068, China
| | - Chenglong Zhu
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Liandong Yang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yandong Ren
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Jue Ruan
- Guangdong Laboratory for Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Guangyi Fan
- BGI-Qingdao, Qingdao 266555, China; BGI-Shenzhen, Shenzhen 518083, China
| | - Jiang Hu
- Grandomics Biosciences, Beijing 102200, China
| | - Wenjie Xu
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China
| | - Xupeng Bi
- BGI-Shenzhen, Shenzhen 518083, China
| | - Youan Zhu
- Institute of Vertebrate Paleontology and Paleoanthropology, China Academy of Sciences, Beijing 100044, China
| | - Yue Song
- BGI-Qingdao, Qingdao 266555, China
| | - Huatao Chen
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Tiantian Ma
- Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northwest A&F University, Yangling 712100, China
| | - Ruoping Zhao
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China
| | - Haifeng Jiang
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Bin Zhang
- Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing 100101, China
| | - Chenguang Feng
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China
| | - Yuan Yuan
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China
| | - Xiaoni Gan
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Yongxin Li
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China
| | - Honghui Zeng
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
| | - Qun Liu
- BGI-Qingdao, Qingdao 266555, China
| | | | - Feng Shao
- Key Laboratory of Freshwater Fish Reproduction and Development, School of Life Sciences, Southwest University, Chongqing 400715, China
| | | | - He Zhang
- BGI-Qingdao, Qingdao 266555, China
| | - Xun Xu
- BGI-Shenzhen, Shenzhen 518083, China
| | - Xin Liu
- BGI-Qingdao, Qingdao 266555, China
| | - Depeng Wang
- Grandomics Biosciences, Beijing 102200, China
| | - Min Zhu
- Institute of Vertebrate Paleontology and Paleoanthropology, China Academy of Sciences, Beijing 100044, China
| | - Guojie Zhang
- BGI-Shenzhen, Shenzhen 518083, China; State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China; Villum Center for Biodiversity Genomics, Section for Ecology and Evolution, Department of Biology, University of Copenhagen, Copenhagen, Denmark
| | - Wenming Zhao
- Beijing Institute of Genomics, Chinese Academy of Sciences, and China National Center for Bioinformation, Beijing 100101, China.
| | - Qiang Qiu
- School of Ecology and Environment, Northwestern Polytechnical University, Xi'an 710072, China.
| | - Shunping He
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China; Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya 572000, China.
| | - Wen Wang
- State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China; Center for Excellence in Animal Evolution and Genetics, Chinese Academy of Sciences, Kunming 650223, China.
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16
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Bulajić M, Srivastava D, Dasen JS, Wichterle H, Mahony S, Mazzoni EO. Differential abilities to engage inaccessible chromatin diversify vertebrate Hox binding patterns. Development 2020; 147:dev194761. [PMID: 33028607 PMCID: PMC7710020 DOI: 10.1242/dev.194761] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Accepted: 09/25/2020] [Indexed: 12/17/2022]
Abstract
Although Hox genes encode for conserved transcription factors (TFs), they are further divided into anterior, central and posterior groups based on their DNA-binding domain similarity. The posterior Hox group expanded in the deuterostome clade and patterns caudal and distal structures. We aimed to address how similar Hox TFs diverge to induce different positional identities. We studied Hox TF DNA-binding and regulatory activity during an in vitro motor neuron differentiation system that recapitulates embryonic development. We found diversity in the genomic binding profiles of different Hox TFs, even among the posterior group paralogs that share similar DNA-binding domains. These differences in genomic binding were explained by differing abilities to bind to previously inaccessible sites. For example, the posterior group HOXC9 had a greater ability to bind occluded sites than the posterior HOXC10, producing different binding patterns and driving differential gene expression programs. From these results, we propose that the differential abilities of posterior Hox TFs to bind to previously inaccessible chromatin drive patterning diversification.This article has an associated 'The people behind the papers' interview.
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Affiliation(s)
- Milica Bulajić
- Department of Biology, New York University, New York, NY 10003, USA
| | - Divyanshi Srivastava
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
| | - Jeremy S Dasen
- Neuroscience Institute, Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016, USA
| | - Hynek Wichterle
- Department of Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
- Department of Neuroscience, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Shaun Mahony
- Center for Eukaryotic Gene Regulation, Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, PA 16802, USA
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17
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Li M, Alsager JS, Wang Z, Cheng L, Shan B. Epigenetic upregulation of HOXC10 in non-small lung cancer cells. Aging (Albany NY) 2020; 12:16921-16935. [PMID: 32687064 PMCID: PMC7521540 DOI: 10.18632/aging.103597] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 06/13/2020] [Indexed: 01/24/2023]
Abstract
The homeobox genes (HOX) have emerged as a new family of master regulators of development and cancer. In the current study, we examined the expression and function of HOXC10 in human non-small cell lung cancer (NSCLC). We observed increased expression of HOXC10 in the more aggressive human NSCLC cell line NCI-H23 over the well differentiated A549 cells. To elucidate the expression and function of HOXC10 in NSCLC cells, we employed RT-PCR, immunoblotting, methylation-specific PCR, apoptosis assays, and xenograft model. Overexpression of HOXC10 in A549 cells conveyed increased proliferation, reduced apoptosis, and accelerated tumor growth when transplanted into nude mice. In contrast, siRNA-mediated knockdown of HOXC10 in NCI-H23 cells reduced proliferation and increased apoptosis. Our results further indicated that hypomethylation of the CpG island in the HOXC10 promoter was critical to elevated expression of HOXC10 in NSCLC cells. Lastly, we identified a G-quadruplex in the HOXC10 promoter and its G-quadruplex formation was required for elevated expression of HOXC10 in NSCLC cells. Moreover our results suggest that disruption of G-quadruplex formation can silence HOXC10 expression in NSCLC cells. In summary, we report HOXC10 as a novel tumor promoting oncogene in NSCLC cells.
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Affiliation(s)
- Miao Li
- Department of Microbiology and Parasitology, College of Basic Medical Sciences, China Medical University, Shenyang, China
| | - John Simon Alsager
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
| | - Zhaokai Wang
- The First Clinical Department of China Medical University, Shenyang, China
| | - Lin Cheng
- The First Clinical Department of China Medical University, Shenyang, China
| | - Bin Shan
- Department of Biomedical Sciences, Elson S. Floyd College of Medicine, Washington State University, Spokane, WA 99202, USA
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18
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Zhang Y, Le Y, Bu P, Cheng X. Regulation of Hox and ParaHox genes by perfluorochemicals in mouse liver. Toxicology 2020; 441:152521. [PMID: 32534105 DOI: 10.1016/j.tox.2020.152521] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/30/2020] [Accepted: 06/08/2020] [Indexed: 01/01/2023]
Abstract
Homeobox (Hox) genes encode homeodomain proteins, which play important roles in the development and morphological diversification of organisms including plants and animals. Perfluorinated chemicals (PFCs), which are well recognized industrial pollutants and universally detected in human and wildlife, interfere with animal development. In addition, PFCs produce a number of hepatic adverse effects, such as hepatomegaly and dyslipidemia. Homeodomain proteins profoundly contribute to liver regeneration. Hox genes serve as either oncogenes or tumor suppressor genes during target organ carcinogenesis. However, to date, no study investigated whether PFCs regulate expression of Hox genes. This study was designed to determine the regulation of Hox (including Hox-a to -d subfamily members) and paraHox [including GS homeobox (Gsx), pancreatic and duodenal homeobox (Pdx), and caudal-related homeobox (Cdx) family members] genes by PFCs including perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) in mouse liver. 46.4 mg/kg PFNA induced mRNA expression of Hoxa5, b7, c5, d10 and Pdx1 in wild-type and CAR-null mouse livers, but not in PPARα-null mouse livers, indicating a PPARα-dependent manner. PFOA, PFNA, and PFDA all induced mRNA expression of Hoxa5, b7, c5, d10, Pdx1 and Zeb2 in wild-type but not PPARα-null mouse livers. In addition, in Nrf2-null mouse livers, PFNA continued to increase mRNA expression of Hoxa5 and Pdx1, but not Hoxb7, c5 or d10. Furthermore, Wy14643, a classical PPARα agonist, induced mRNA expression of Hoxb7 and c5 in wild-type but not PPARα-null mouse livers. However, Wy14643 did not induce mRNA expression of Hoxa5, d10 or Pdx1 in either wild-type or PPARα-null mouse livers. TCPOBOP, a classical mouse CAR agonist, increased mRNA expression of Hoxb7, c5 and d10 but not Hoxa5 or Pdx1 in mouse livers. Moreover, PFNA decreased cytoplasmic and nuclear Hoxb7 protein levels in mouse livers. However, PFNA increased cytoplasmic Hoxc5 protein level but decreased nuclear Hoxc5 protein level in mouse livers. In conclusion, PFCs induced mRNA expression of several Hox genes such as Hoxb7, c5 and d10, mostly through the activation of PPARα and/or Nrf2 signaling.
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Affiliation(s)
- Yue Zhang
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, 11439, United States
| | - Yuan Le
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, 11439, United States
| | - Pengli Bu
- Department of Pharmaceutical Sciences, College of Pharmacy, Rosalind Franklin University of Medicine and Science, Chicago, IL, 60064, United States
| | - Xingguo Cheng
- Department of Pharmaceutical Sciences, College of Pharmacy and Health Sciences, St. John's University, Queens, NY, 11439, United States.
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19
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Loffreda A, Nizzardo M, Arosio A, Ruepp MD, Calogero RA, Volinia S, Galasso M, Bendotti C, Ferrarese C, Lunetta C, Rizzuti M, Ronchi AE, Mühlemann O, Tremolizzo L, Corti S, Barabino SML. miR-129-5p: A key factor and therapeutic target in amyotrophic lateral sclerosis. Prog Neurobiol 2020; 190:101803. [PMID: 32335272 DOI: 10.1016/j.pneurobio.2020.101803] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 04/02/2020] [Accepted: 04/09/2020] [Indexed: 12/30/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) is a relentless and fatal neurological disease characterized by the selective degeneration of motor neurons. No effective therapy is available for this disease. Several lines of evidence indicate that alteration of RNA metabolism, including microRNA (miRNA) processing, is a relevant pathogenetic factor and a possible therapeutic target for ALS. Here, we showed that the abundance of components in the miRNA processing machinery is altered in a SOD1-linked cellular model, suggesting consequent dysregulation of miRNA biogenesis. Indeed, high-throughput sequencing of the small RNA fraction showed that among the altered miRNAs, miR-129-5p was increased in different models of SOD1-linked ALS and in peripheral blood cells of sporadic ALS patients. We demonstrated that miR-129-5p upregulation causes the downregulation of one of its targets: the RNA-binding protein ELAVL4/HuD. ELAVL4/HuD is predominantly expressed in neurons, where it controls several key neuronal mRNAs. Overexpression of pre-miR-129-1 inhibited neurite outgrowth and differentiation via HuD silencing in vitro, while its inhibition with an antagomir rescued the phenotype. Remarkably, we showed that administration of an antisense oligonucleotide (ASO) inhibitor of miR-129-5p to an ALS animal model, SOD1 (G93A) mice, result in a significant increase in survival and improved the neuromuscular phenotype in treated mice. These results identify miR-129-5p as a therapeutic target that is amenable to ASO modulation for the treatment of ALS patients.
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Affiliation(s)
- Alessia Loffreda
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Monica Nizzardo
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Alessandro Arosio
- School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, 20052 Monza, MB, Italy
| | - Marc-David Ruepp
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Raffaele A Calogero
- Department of Molecular Biotechnology and Health Sciences, University of Torino, 10126 Turin, Italy
| | - Stefano Volinia
- Department of Morphology, Surgery and Experimental Medicine, Università degli Studi, 44121 Ferrara, Italy
| | - Marco Galasso
- Department of Morphology, Surgery and Experimental Medicine, Università degli Studi, 44121 Ferrara, Italy
| | - Caterina Bendotti
- Department of Neuroscience, IRCCS-Istituto di Ricerche Farmacologiche "Mario Negri", 20156 Milan, Italy
| | - Carlo Ferrarese
- School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, 20052 Monza, MB, Italy; Neurology Unit, San Gerardo Hospital, Monza, MB, Italy
| | - Christian Lunetta
- NEuroMuscular Omnicentre (NEMO), Fondazione Serena Onlus, 20162 Milan, Italy
| | - Mafalda Rizzuti
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Antonella E Ronchi
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
| | - Oliver Mühlemann
- Department of Chemistry and Biochemistry, University of Bern, 3012 Bern, Switzerland
| | - Lucio Tremolizzo
- School of Medicine and Surgery and Milan Center for Neuroscience (NeuroMI), University of Milano-Bicocca, 20052 Monza, MB, Italy; Neurology Unit, San Gerardo Hospital, Monza, MB, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Neuroscience Section, Department of Pathophysiology and Transplantation (DEPT), University of Milan, Italy; Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Neurology Unit, Milan, Italy
| | - Silvia M L Barabino
- Department of Biotechnology and Biosciences, University of Milano-Bicocca, Milan, Italy
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20
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Sagner A, Briscoe J. Establishing neuronal diversity in the spinal cord: a time and a place. Development 2019; 146:146/22/dev182154. [DOI: 10.1242/dev.182154] [Citation(s) in RCA: 137] [Impact Index Per Article: 27.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
ABSTRACT
The vertebrate spinal cord comprises multiple functionally distinct neuronal cell types arranged in characteristic positions. During development, these different types of neurons differentiate from transcriptionally distinct neural progenitors that are arrayed in discrete domains along the dorsal-ventral and anterior-posterior axes of the embryonic spinal cord. This organization arises in response to morphogen gradients acting upstream of a gene regulatory network, the architecture of which determines the spatial and temporal pattern of gene expression. In recent years, substantial progress has been made in deciphering the regulatory network that underlies the specification of distinct progenitor and neuronal cell identities. In this Review, we outline how distinct neuronal cell identities are established in response to spatial and temporal patterning systems, and outline novel experimental approaches to study the emergence and function of neuronal diversity in the spinal cord.
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21
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Coughlan E, Garside VC, Wong SFL, Liang H, Kraus D, Karmakar K, Maheshwari U, Rijli FM, Bourne J, McGlinn E. A Hox Code Defines Spinocerebellar Neuron Subtype Regionalization. Cell Rep 2019; 29:2408-2421.e4. [DOI: 10.1016/j.celrep.2019.10.048] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Revised: 08/12/2019] [Accepted: 10/10/2019] [Indexed: 11/25/2022] Open
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22
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Nam H, Jeon S, An H, Yoo J, Lee HJ, Lee SK, Lee S. Critical roles of ARHGAP36 as a signal transduction mediator of Shh pathway in lateral motor columnar specification. eLife 2019; 8:46683. [PMID: 31305241 PMCID: PMC6658197 DOI: 10.7554/elife.46683] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/14/2019] [Indexed: 01/20/2023] Open
Abstract
During spinal cord development, Sonic hedgehog (Shh), secreted from the floor plate, plays an important role in the production of motor neurons by patterning the ventral neural tube, which establishes MN progenitor identity. It remains unknown, however, if Shh signaling plays a role in generating columnar diversity of MNs that connect distinct target muscles. Here, we report that Shh, expressed in MNs, is essential for the formation of lateral motor column (LMC) neurons in vertebrate spinal cord. This novel activity of Shh is mediated by its downstream effector ARHGAP36, whose expression is directly induced by the MN-specific transcription factor complex Isl1-Lhx3. Furthermore, we found that AKT stimulates the Shh activity to induce LMC MNs through the stabilization of ARHGAP36 proteins. Taken together, our data reveal that Shh, secreted from MNs, plays a crucial role in generating MN diversity via a regulatory axis of Shh-AKT-ARHGAP36 in the developing mouse spinal cord.
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Affiliation(s)
- Heejin Nam
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Shin Jeon
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea.,Neuroscience Section, Papé Family Pediatric Research Institute, Department of Pediatrics, Oregon Health and Science Uiversity, Portland, United States
| | - Hyejin An
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Jaeyoung Yoo
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Hyo-Jong Lee
- College of Pharmacy and Inje Institute of Pharmaceutical Sciences and Research, Inje University, Gyungnam, Republic of Korea
| | - Soo-Kyung Lee
- Neuroscience Section, Papé Family Pediatric Research Institute, Department of Pediatrics, Oregon Health and Science Uiversity, Portland, United States.,Vollum Institute, Oregon Health and Science University, Portland, United States
| | - Seunghee Lee
- College of Pharmacy and Research Institute of Pharmaceutical Sciences, Seoul National University, Seoul, Republic of Korea
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23
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Guan Y, He Y, Lv S, Hou X, Li L, Song J. Overexpression of HOXC10 promotes glioblastoma cell progression to a poor prognosis via the PI3K/AKT signalling pathway. J Drug Target 2018; 27:60-66. [PMID: 29768063 DOI: 10.1080/1061186x.2018.1473408] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
OBJECTIVE The HOX gene is expressed in neoplasias occurred in multiple tissues, such as the colon, lung and breast. However, the effects of the HOX gene on glioblastoma (GBM) remain poorly understood. We examined HOXC10 expression in GBM tissues and cells, analysed its effect on GBM prognosis, and finally assessed its possible underlying mechanisms in this study. METHODS HOXC10 expression levels and its prognostic effects on GBM tissues were analysed based on The Cancer Genome Atlas (TCGA) and ONCOMINE database. Overall survival (OS) analysis was performed using the Kaplan-Meier method and log rank test. Then, the expression of HOXC10 was detected in four GBM cell lines using quantitative real-time reverse transcription-PCR (qRT-PCR). In addition, small interfering RNA (si-RNA) was utilised in the U87 cell line with the highest HOXC10 expression to facilitate subsequent in vitro cell experiment. Cell proliferation, migration and invasion were assessed using the Cell Counting Kit-8 (CCK-8) and colony formation assay, wound healing, Transwell assay, respectively in GBM U87 cell after HOXC10 knockdown. Key proteins related to the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signalling pathway were measured by western blotting. RESULTS HOXC10 expression was significantly increased in GBM tissues and cell lines, leading a poor OS in GBM patients. Knockdown of HOXC10 could inhibit the GBM U87 cells proliferation, migration and invasion, as well as decreased expression levels of key proteins in PI3K/AKT signalling pathway. CONCLUSION HOXC10 was overexpressed in GBM tissues and cells, and associated with poor prognosis in GBM patients. Moreover, HOXC10 knockdown inhibited U87 cell proliferation, migration and invasion, which were potentially related to PI3K/AKT signalling pathway activation. Our findings revealed that HOXC10 represent a promising biological target for GBM treatment in the future.
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Affiliation(s)
- Yong Guan
- a Department of Neurosurgery , Qingdao Minicipal Hospital , Qingdao , Shandong , PR China
| | - Yajie He
- a Department of Neurosurgery , Qingdao Minicipal Hospital , Qingdao , Shandong , PR China
| | - Shaoping Lv
- b Department of Rehabilitation , Qingdao Central Hospital , Qingdao , Shandong , PR China
| | - Xiaoqun Hou
- a Department of Neurosurgery , Qingdao Minicipal Hospital , Qingdao , Shandong , PR China
| | - Luo Li
- a Department of Neurosurgery , Qingdao Minicipal Hospital , Qingdao , Shandong , PR China
| | - Jianjun Song
- a Department of Neurosurgery , Qingdao Minicipal Hospital , Qingdao , Shandong , PR China
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24
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Abstract
Motor neurons of the spinal cord are responsible for the assembly of neuromuscular connections indispensable for basic locomotion and skilled movements. A precise spatial relationship exists between the position of motor neuron cell bodies in the spinal cord and the course of their axonal projections to peripheral muscle targets. Motor neuron innervation of the vertebrate limb is a prime example of this topographic organization and by virtue of its accessibility and predictability has provided access to fundamental principles of motor system development and neuronal guidance. The seemingly basic binary map established by genetically defined motor neuron subtypes that target muscles in the limb is directed by a surprisingly large number of directional cues. Rather than being simply redundant, these converging signaling pathways are hierarchically linked and cooperate to increase the fidelity of axon pathfinding decisions. A current priority is to determine how multiple guidance signals are integrated by individual growth cones and how they synergize to delineate class-specific axonal trajectories.
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Affiliation(s)
- Dario Bonanomi
- Molecular Neurobiology Laboratory, Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy.
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25
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Mukaigasa K, Sakuma C, Okada T, Homma S, Shimada T, Nishiyama K, Sato N, Yaginuma H. Motor neurons with limb-innervating character in the cervical spinal cord are sculpted by apoptosis based on the Hox code in chick embryo. Development 2017; 144:4645-4657. [PMID: 29061638 DOI: 10.1242/dev.158873] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2017] [Accepted: 10/16/2017] [Indexed: 12/13/2022]
Abstract
In the developing chick embryo, a certain population of motor neurons (MNs) in the non-limb-innervating cervical spinal cord undergoes apoptosis between embryonic days 4 and 5. However, the characteristics of these apoptotic MNs remain undefined. Here, by examining the spatiotemporal profiles of apoptosis and MN subtype marker expression in normal or apoptosis-inhibited chick embryos, we found that this apoptotic population is distinguishable by Foxp1 expression. When apoptosis was inhibited, the Foxp1+ MNs survived and showed characteristics of lateral motor column (LMC) neurons, which are of a limb-innervating subtype, suggesting that cervical Foxp1+ MNs are the rostral continuation of the LMC. Knockdown and misexpression of Foxp1 did not affect apoptosis progression, but revealed the role of Foxp1 in conferring LMC identity on the cervical MNs. Furthermore, ectopic expression of Hox genes that are normally expressed in the brachial region prevented apoptosis, and directed Foxp1+ MNs to LMC neurons at the cervical level. These results indicate that apoptosis in the cervical spinal cord plays a role in sculpting Foxp1+ MNs committed to LMC neurons, depending on the Hox expression pattern.
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Affiliation(s)
- Katsuki Mukaigasa
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Chie Sakuma
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Tomoaki Okada
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Shunsaku Homma
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Takako Shimada
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Keiji Nishiyama
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
| | - Noboru Sato
- Division of Gross Anatomy and Morphogenesis, Niigata University Graduate School of Medical and Dental Sciences, Niigata 951-8510, Japan
| | - Hiroyuki Yaginuma
- Department of Neuroanatomy and Embryology, School of Medicine, Fukushima Medical University, Fukushima 960-1295, Japan
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26
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Kratsios P, Kerk SY, Catela C, Liang J, Vidal B, Bayer EA, Feng W, De La Cruz ED, Croci L, Consalez GG, Mizumoto K, Hobert O. An intersectional gene regulatory strategy defines subclass diversity of C. elegans motor neurons. eLife 2017; 6. [PMID: 28677525 PMCID: PMC5498135 DOI: 10.7554/elife.25751] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Accepted: 06/13/2017] [Indexed: 01/09/2023] Open
Abstract
A core principle of nervous system organization is the diversification of neuron classes into subclasses that share large sets of features but differ in select traits. We describe here a molecular mechanism necessary for motor neurons to acquire subclass-specific traits in the nematode Caenorhabditis elegans. Cholinergic motor neuron classes of the ventral nerve cord can be subdivided into subclasses along the anterior-posterior (A-P) axis based on synaptic connectivity patterns and molecular features. The conserved COE-type terminal selector UNC-3 not only controls the expression of traits shared by all members of a neuron class, but is also required for subclass-specific traits expressed along the A-P axis. UNC-3, which is not regionally restricted, requires region-specific cofactors in the form of Hox proteins to co-activate subclass-specific effector genes in post-mitotic motor neurons. This intersectional gene regulatory principle for neuronal subclass diversification may be conserved from nematodes to mice.
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Affiliation(s)
- Paschalis Kratsios
- Department of Neurobiology, University of Chicago, Chicago, United States
| | - Sze Yen Kerk
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Catarina Catela
- Department of Neurobiology, University of Chicago, Chicago, United States
| | - Joseph Liang
- Department of Zoology, The University of British Columbia, Vancouver, Canada
| | - Berta Vidal
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Emily A Bayer
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Weidong Feng
- Department of Neurobiology, University of Chicago, Chicago, United States
| | - Estanisla Daniel De La Cruz
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
| | - Laura Croci
- Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy
| | - G Giacomo Consalez
- Division of Neuroscience, San Raffaele Scientific Institute, Milan, Italy.,Università Vita-Salute San Raffaele, Milan, Italy
| | - Kota Mizumoto
- Department of Zoology, The University of British Columbia, Vancouver, Canada
| | - Oliver Hobert
- Department of Biological Sciences, Howard Hughes Medical Institute, Columbia University, New York, United States
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27
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Divergent Hox Coding and Evasion of Retinoid Signaling Specifies Motor Neurons Innervating Digit Muscles. Neuron 2017; 93:792-805.e4. [PMID: 28190640 DOI: 10.1016/j.neuron.2017.01.017] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Revised: 12/13/2016] [Accepted: 01/20/2017] [Indexed: 11/21/2022]
Abstract
The establishment of spinal motor neuron subclass diversity is achieved through developmental programs that are aligned with the organization of muscle targets in the limb. The evolutionary emergence of digits represents a specialized adaptation of limb morphology, yet it remains unclear how the specification of digit-innervating motor neuron subtypes parallels the elaboration of digits. We show that digit-innervating motor neurons can be defined by selective gene markers and distinguished from other LMC neurons by the expression of a variant Hox gene repertoire and by the failure to express a key enzyme involved in retinoic acid synthesis. This divergent developmental program is sufficient to induce the specification of digit-innervating motor neurons, emphasizing the specialized status of digit control in the evolution of skilled motor behaviors. Our findings suggest that the emergence of digits in the limb is matched by distinct mechanisms for specifying motor neurons that innervate digit muscles.
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28
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Lan H, Li S, Guo Z, Men H, Wu Y, Li N, Bryda EC, Capecchi MR, Wu S. Efficient generation of selection-gene-free rat knockout models by homologous recombination in ES cells. FEBS Lett 2016; 590:3416-3424. [PMID: 27597178 PMCID: PMC5129459 DOI: 10.1002/1873-3468.12388] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2016] [Revised: 08/24/2016] [Accepted: 08/25/2016] [Indexed: 11/25/2022]
Abstract
Embryonic stem cell (ES cell)‐based rat knockout technology, although successfully developed in 2010, has seen very limited usage to date due to low targeting efficiency and a lack of optimized procedures. In this study, we performed gene targeting in ES cells from the Sprague–Dawley (SD) and the Fischer 344 (F344) rat strains using an optimized procedure and the self‐excising neomycin (neo)‐positive selection cassette ACN to successfully generate Leptin and Trp53 knockout rats that did not carry the selection gene. These results demonstrate that our simplified targeting strategy using ACN provides an efficient approach to knock out many other rat genes.
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Affiliation(s)
- He Lan
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Shuping Li
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Zihang Guo
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Hongsheng Men
- Veterinary Pathobiology, Rat Resource and Research Center, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Yuanyuan Wu
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Ning Li
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China
| | - Elizabeth C Bryda
- Veterinary Pathobiology, Rat Resource and Research Center, College of Veterinary Medicine, University of Missouri, Columbia, MO, USA
| | - Mario R Capecchi
- Department of Human Genetics, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Sen Wu
- State Key Laboratory of Agrobiotechnology, College of Biological Sciences, China Agricultural University, Beijing, China.
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29
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Lai YJ, Yu D, Zhang JH, Chen GJ. Cooperation of Genomic and Rapid Nongenomic Actions of Estrogens in Synaptic Plasticity. Mol Neurobiol 2016; 54:4113-4126. [PMID: 27324789 PMCID: PMC5509832 DOI: 10.1007/s12035-016-9979-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/14/2016] [Indexed: 12/23/2022]
Abstract
Neuroplasticity refers to the changes in the molecular and cellular processes of neural circuits that occur in response to environmental experiences. Clinical and experimental studies have increasingly shown that estrogens participate in the neuroplasticity involved in cognition, behavior, and memory. It is generally accepted that estrogens exert their effects through genomic actions that occur over a period of hours to days. However, emerging evidence indicates that estrogens also rapidly influence the neural circuitry through nongenomic actions. In this review, we provide an overview of the genomic and nongenomic actions of estrogens and discuss how these actions may cooperate in synaptic plasticity. We then summarize the role of epigenetic modifications, synaptic protein synthesis, and posttranslational modifications, and the splice variants of estrogen receptors in the complicated network of estrogens. The combination of genomic and nongenomic mechanisms endows estrogens with considerable diversity in modulating neural functions including synaptic plasticity.
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Affiliation(s)
- Yu-Jie Lai
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - Dan Yu
- Department of Neurology, Affiliated Haikou Hospital of Xiangya Medical College of Central South University, Haikou Municipal Hospital, Haikou, Hainan, 570208, China
| | - John H Zhang
- Department of Anesthesiology, Loma Linda University School of Medicine, Loma Linda, CA, 92354, USA
| | - Guo-Jun Chen
- Department of Neurology, the First Affiliated Hospital of Chongqing Medical University, Chongqing Key Laboratory of Neurology, 1 Youyi Road, Chongqing, 400016, China.
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30
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Developmental Mechanism of Limb Field Specification along the Anterior-Posterior Axis during Vertebrate Evolution. J Dev Biol 2016; 4:jdb4020018. [PMID: 29615584 PMCID: PMC5831784 DOI: 10.3390/jdb4020018] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Revised: 05/16/2016] [Accepted: 05/17/2016] [Indexed: 12/19/2022] Open
Abstract
In gnathostomes, limb buds arise from the lateral plate mesoderm at discrete positions along the body axis. Specification of these limb-forming fields can be subdivided into several steps. The lateral plate mesoderm is regionalized into the anterior lateral plate mesoderm (ALPM; cardiac mesoderm) and the posterior lateral plate mesoderm (PLPM). Subsequently, Hox genes appear in a nested fashion in the PLPM and provide positional information along the body axis. The lateral plate mesoderm then splits into the somatic and splanchnic layers. In the somatic layer of the PLPM, the expression of limb initiation genes appears in the limb-forming region, leading to limb bud initiation. Furthermore, past and current work in limbless amphioxus and lampreys suggests that evolutionary changes in developmental programs occurred during the acquisition of paired fins during vertebrate evolution. This review presents these recent advances and discusses the mechanisms of limb field specification during development and evolution, with a focus on the role of Hox genes in this process.
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31
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Wiese S. Factors influencing the spinal motoneurons in development. Neural Regen Res 2016; 10:1773-6. [PMID: 26807112 PMCID: PMC4705789 DOI: 10.4103/1673-5374.169639] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The development of the spinal cord needs a concerted interaction of transcription factors activating diverse genes and signals from outside acting on the specification of the different cells. Signals have to act on the segments of the embryo as well as on the cranial-caudal axis and the dorso-ventral axis. Additionally the axons of the motoneurons have to cross the central nervous system barrier to connect to the periphery. Intensive anatomical studies have been followed by molecular characterization of the different subsets of transcription factors that are expressed by cells of the developing spinal cord. Here, intensive studies for the most important appearing cells, the motoneurons, have resulted in a good knowledge on the expression patterns of these proteins. Nonetheless motoneurons are by far not the only important cells and the concert activity of all cells besides them is necessary for the correct function and integrity of motoneurons within the spinal cord. This article will briefly summarize the different aspects on spinal cord development and focuses on the differentiation as well as the functionalization of motoneurons.
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Affiliation(s)
- Stefan Wiese
- Faculty for Biology and Biotechnology, Group for Molecular Cell Biology, Universitaetsstr. 150, Ruhr University Bochum, D-44801 Bochum, Germany
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32
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Wiese S, Faissner A. The role of extracellular matrix in spinal cord development. Exp Neurol 2015; 274:90-9. [DOI: 10.1016/j.expneurol.2015.05.018] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 05/13/2015] [Accepted: 05/25/2015] [Indexed: 01/06/2023]
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33
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Zheng C, Jin FQ, Chalfie M. Hox Proteins Act as Transcriptional Guarantors to Ensure Terminal Differentiation. Cell Rep 2015; 13:1343-1352. [PMID: 26547238 DOI: 10.1016/j.celrep.2015.10.044] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Revised: 09/29/2015] [Accepted: 10/19/2015] [Indexed: 11/18/2022] Open
Abstract
Cell differentiation usually occurs with high fidelity, but the expression of many transcription factors is variable. Using the touch receptor neurons (TRNs) in C. elegans, we found that the Hox proteins CEH-13/lab and EGL-5/Abd-B overcome this variability by facilitating the activation of the common TRN fate determinant mec-3 in the anterior and posterior TRNs, respectively. CEH-13 and EGL-5 increase the probability of mec-3 transcriptional activation by the POU-homeodomain transcription factor UNC-86 using the same Hox/Pbx binding site. Mutation of ceh-13 and egl-5 resulted in an incomplete (∼40%) loss of the TRN fate in respective TRNs, which correlates with quantitative mRNA measurements showing two distinct modes (all or none) of mec-3 transcription. Therefore, Hox proteins act as transcriptional "guarantors" in order to ensure reliable and robust gene expression during terminal neuronal differentiation. Guarantors do not activate gene expression by themselves but promote full activation of target genes regulated by other transcription factors.
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Affiliation(s)
- Chaogu Zheng
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Felix Qiaochu Jin
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA
| | - Martin Chalfie
- Department of Biological Sciences, Columbia University, New York, NY 10027, USA.
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34
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Upregulation of long non-coding RNA HIF 1α-anti-sense 1 induced by transforming growth factor-β-mediated targeting of sirtuin 1 promotes osteoblastic differentiation of human bone marrow stromal cells. Mol Med Rep 2015; 12:7233-8. [PMID: 26460121 PMCID: PMC4626181 DOI: 10.3892/mmr.2015.4415] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 07/21/2015] [Indexed: 12/02/2022] Open
Abstract
The present study aimed to investigate the regulatory mechanism of long non-coding RNA hypoxia-inducible factor 1α-anti-sense 1 (lncRNA HIF1α-AS1) in osteoblast differentiation as well as its targeting by sirtuin 1 (SIRT1), which may be inhibited by transforming growth factor (TGF)-β in bone marrow stromal cells (BMSCs). Real-time polymerase chain reaction (PCR), western blot analysis, lncRNA PCR arrays and chromatin immunoprecipitation were performed in order to examine the interference of SIRT1 expression by TGF-β, the effects of SIRT1 overexpression on lncRNA HIF1α-AS1 and the regulation of the expression of homeobox (HOX)D10, which promotes BMSC differentiation, by lncRNA HIF1α-AS1. The results showed that TGF-β interfered with SIRT1 expression. Furthermore, lncRNA HIF1α-AS1 was significantly downregulated following overexpression of SIRT1. In addition, low expression of HIF1α-AS1 was sufficient to block the expression of HOXD10. The present study further demonstrated that downregulation of HOXD10 by HIF1α-AS1 interfered with acetylation, and subsequently resulted in the inhibition of osteoblast differentiation. These results suggested that HIF1α-AS1 is an essential mediator of osteoblast differentiation, and may thus represent a gene-therapeutic agent for the treatment of human bone diseases.
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35
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Abstract
Control of movement is a fundamental and complex task of the vertebrate nervous system, which relies on communication between circuits distributed throughout the brain and spinal cord. Many of the networks essential for the execution of basic locomotor behaviors are composed of discrete neuronal populations residing within the spinal cord. The organization and connectivity of these circuits is established through programs that generate functionally diverse neuronal subtypes, each contributing to a specific facet of motor output. Significant progress has been made in deciphering how neuronal subtypes are specified and in delineating the guidance and synaptic specificity determinants at the core of motor circuit assembly. Recent studies have shed light on the basic principles linking locomotor circuit connectivity with function, and they are beginning to reveal how more sophisticated motor behaviors are encoded. In this review, we discuss the impact of developmental programs in specifying motor behaviors governed by spinal circuits.
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Affiliation(s)
- Catarina Catela
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
| | - Maggie M Shin
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
| | - Jeremy S Dasen
- Neuroscience Institute and Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016;
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36
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Woltering JM, Duboule D. Tetrapod axial evolution and developmental constraints; Empirical underpinning by a mouse model. Mech Dev 2015; 138 Pt 2:64-72. [PMID: 26238020 PMCID: PMC4678112 DOI: 10.1016/j.mod.2015.07.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2015] [Revised: 07/19/2015] [Accepted: 07/20/2015] [Indexed: 02/05/2023]
Abstract
The tetrapod vertebral column has become increasingly complex during evolution as an adaptation to a terrestrial life. At the same time, the evolution of the vertebral formula became subject to developmental constraints acting on the size of the cervical and thoraco-lumbar regions. In the course of our studies concerning the evolution of Hox gene regulation, we produced a transgenic mouse model expressing fish Hox genes, which displayed a reduced number of thoraco-lumbar vertebrae and concurrent sacral homeotic transformations. Here, we analyze this mutant stock and conclude that the ancestral, pre-tetrapodial Hox code already possessed the capacity to induce vertebrae with sacral characteristics. This suggests that alterations in the interpretation of the Hox code may have participated to the evolution of this region in tetrapods, along with potential modifications of the HOX proteins themselves. With its reduced vertebral number, this mouse stock violates a previously described developmental constraint, which applies to the thoraco-lumbar region. The resulting offset between motor neuron morphology, vertebral patterning and the relative positioning of hind limbs illustrates that the precise orchestration of the Hox-clock in parallel with other ontogenetic pathways places constraints on the evolvability of the body plan. A transgenic mouse line expressing fish Hox genes has anterior homeotic transformations. Fish Hox genes are capable of inducing tetrapod specific vertebral characters. A sacral Hox-code influences adult hindlimb position, yet not the position of limb budding.
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Affiliation(s)
- Joost M Woltering
- Department of Genetics and Evolution, University of Geneva, 30 quai Ernest Ansermet, 1211 Geneva, Switzerland
| | - Denis Duboule
- Department of Genetics and Evolution, University of Geneva, 30 quai Ernest Ansermet, 1211 Geneva, Switzerland; School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland.
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37
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Allan DW, Thor S. Transcriptional selectors, masters, and combinatorial codes: regulatory principles of neural subtype specification. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2015; 4:505-28. [PMID: 25855098 PMCID: PMC4672696 DOI: 10.1002/wdev.191] [Citation(s) in RCA: 85] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 03/04/2015] [Accepted: 03/04/2015] [Indexed: 01/08/2023]
Abstract
The broad range of tissue and cellular diversity of animals is generated to a large extent by the hierarchical deployment of sequence-specific transcription factors and co-factors (collectively referred to as TF's herein) during development. Our understanding of these developmental processes has been facilitated by the recognition that the activities of many TF's can be meaningfully described by a few functional categories that usefully convey a sense for how the TF's function, and also provides a sense for the regulatory organization of the developmental processes in which they participate. Here, we draw on examples from studies in Caenorhabditis elegans, Drosophila melanogaster, and vertebrates to discuss how the terms spatial selector, temporal selector, tissue/cell type selector, terminal selector and combinatorial code may be usefully applied to categorize the activities of TF's at critical steps of nervous system construction. While we believe that these functional categories are useful for understanding the organizational principles by which TF's direct nervous system construction, we however caution against the assumption that a TF's function can be solely or fully defined by any single functional category. Indeed, most TF's play diverse roles within different functional categories, and their roles can blur the lines we draw between these categories. Regardless, it is our belief that the concepts discussed here are helpful in clarifying the regulatory complexities of nervous system development, and hope they prove useful when interpreting mutant phenotypes, designing future experiments, and programming specific neuronal cell types for use in therapies. WIREs Dev Biol 2015, 4:505–528. doi: 10.1002/wdev.191 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Douglas W Allan
- Department of Cellular and Physiological Sciences, Life Sciences Institute, University of British Columbia, Vancouver, Canada
| | - Stefan Thor
- Department of Clinical and Experimental Medicine, Linkoping University, Linkoping, Sweden
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Narendra V, Rocha PP, An D, Raviram R, Skok JA, Mazzoni EO, Reinberg D. CTCF establishes discrete functional chromatin domains at the Hox clusters during differentiation. Science 2015; 347:1017-21. [PMID: 25722416 DOI: 10.1126/science.1262088] [Citation(s) in RCA: 394] [Impact Index Per Article: 43.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Polycomb and Trithorax group proteins encode the epigenetic memory of cellular positional identity by establishing inheritable domains of repressive and active chromatin within the Hox clusters. Here we demonstrate that the CCCTC-binding factor (CTCF) functions to insulate these adjacent yet antagonistic chromatin domains during embryonic stem cell differentiation into cervical motor neurons. Deletion of CTCF binding sites within the Hox clusters results in the expansion of active chromatin into the repressive domain. CTCF functions as an insulator by organizing Hox clusters into spatially disjoint domains. Ablation of CTCF binding disrupts topological boundaries such that caudal Hox genes leave the repressed domain and become subject to transcriptional activation. Hence, CTCF is required to insulate facultative heterochromatin from impinging euchromatin to produce discrete positional identities.
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Affiliation(s)
- Varun Narendra
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA. Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA
| | - Pedro P Rocha
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Disi An
- Department of Biology, New York University, New York, NY 10003, USA
| | - Ramya Raviram
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Jane A Skok
- Department of Pathology, New York University School of Medicine, New York, NY 10016, USA
| | - Esteban O Mazzoni
- Department of Biology, New York University, New York, NY 10003, USA.
| | - Danny Reinberg
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA. Department of Biochemistry and Molecular Pharmacology, New York University School of Medicine, New York, NY 10016, USA.
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The spinal cord of the common marmoset (Callithrix jacchus). Neurosci Res 2015; 93:164-75. [PMID: 25575643 DOI: 10.1016/j.neures.2014.12.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2014] [Revised: 12/22/2014] [Accepted: 12/24/2014] [Indexed: 11/24/2022]
Abstract
The marmoset spinal cord possesses all the characteristic features of a typical mammalian spinal cord, but with some interesting variation in the levels of origin of the limb nerves. In our study Nissl and ChAT sections of the each segment of the spinal cord in two marmosets (Ma5 and Ma8), we found that the spinal cord can be functionally and anatomically divided into six regions: the prebrachial region (C1 to C3); the brachial region (C4 to C8) - segments supplying the upper limb; the post-brachial region (T1 to L1) - containing the sympathetic outflow, and supplying the hypaxial muscles of the body wall; the crural region (L2 to L5) - segments supplying the lower limb; the postcrural region (L6) - containing the parasympathetic outflow; and the caudal region (L7 to Co4) - supplying the tail. In the rat, mouse, and rhesus monkey, the prebrachial region consists of segments C1 to C4 (with the phrenic nucleus located at the C4 segment), and the brachial region extends from C5 to T1 inclusive. The prefixing of the upper limb outflow in these two marmosets mirrors the finding in the literature that a large C4 contribution to the brachial plexus is common in humans.
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Allodi I, Hedlund E. Directed midbrain and spinal cord neurogenesis from pluripotent stem cells to model development and disease in a dish. Front Neurosci 2014; 8:109. [PMID: 24904255 PMCID: PMC4033221 DOI: 10.3389/fnins.2014.00109] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2014] [Accepted: 04/28/2014] [Indexed: 12/29/2022] Open
Abstract
Induction of specific neuronal fates is restricted in time and space in the developing CNS through integration of extrinsic morphogen signals and intrinsic determinants. Morphogens impose regional characteristics on neural progenitors and establish distinct progenitor domains. Such domains are defined by unique expression patterns of fate determining transcription factors. These processes of neuronal fate specification can be recapitulated in vitro using pluripotent stem cells. In this review, we focus on the generation of dopamine neurons and motor neurons, which are induced at ventral positions of the neural tube through Sonic hedgehog (Shh) signaling, and defined at anteroposterior positions by fibroblast growth factor (Fgf) 8, Wnt1, and retinoic acid (RA). In vitro utilization of these morphogenic signals typically results in the generation of multiple neuronal cell types, which are defined at the intersection of these signals. If the purpose of in vitro neurogenesis is to generate one cell type only, further lineage restriction can be accomplished by forced expression of specific transcription factors in a permissive environment. Alternatively, cell-sorting strategies allow for selection of neuronal progenitors or mature neurons. However, modeling development, disease and prospective therapies in a dish could benefit from structured heterogeneity, where desired neurons are appropriately synaptically connected and thus better reflect the three-dimensional structure of that region. By modulating the extrinsic environment to direct sequential generation of neural progenitors within a domain, followed by self-organization and synaptic establishment, a reductionist model of that brain region could be created. Here we review recent advances in neuronal fate induction in vitro, with a focus on the interplay between cell intrinsic and extrinsic factors, and discuss the implications for studying development and disease in a dish.
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Affiliation(s)
- Ilary Allodi
- Department of Neuroscience, Karolinska Institutet Stockholm, Sweden
| | - Eva Hedlund
- Department of Neuroscience, Karolinska Institutet Stockholm, Sweden
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Jung H, Mazzoni EO, Soshnikova N, Hanley O, Venkatesh B, Duboule D, Dasen JS. Evolving Hox activity profiles govern diversity in locomotor systems. Dev Cell 2014; 29:171-87. [PMID: 24746670 DOI: 10.1016/j.devcel.2014.03.008] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 03/07/2014] [Accepted: 03/13/2014] [Indexed: 11/28/2022]
Abstract
The emergence of limb-driven locomotor behaviors was a key event in the evolution of vertebrates and fostered the transition from aquatic to terrestrial life. We show that the generation of limb-projecting lateral motor column (LMC) neurons in mice relies on a transcriptional autoregulatory module initiated via transient activity of multiple genes within the HoxA and HoxC clusters. Repression of this module at thoracic levels restricts expression of LMC determinants, thus dictating LMC position relative to the limbs. This suppression is mediated by a key regulatory domain that is specifically found in the Hoxc9 proteins of appendage-bearing vertebrates. The profile of Hoxc9 expression inversely correlates with LMC position in land vertebrates and likely accounts for the absence of LMC neurons in limbless species such as snakes. Thus, modulation of both Hoxc9 protein function and Hoxc9 gene expression likely contributed to evolutionary transitions between undulatory and ambulatory motor circuit connectivity programs.
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Affiliation(s)
- Heekyung Jung
- Howard Hughes Medical Institute, NYU Neuroscience Institute, Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016, USA
| | | | - Natalia Soshnikova
- Department of Genetics and Evolution, University of Geneva, Sciences III, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland; Institute of Molecular Biology, Ackermannweg 4, 55128 Mainz, Germany
| | - Olivia Hanley
- Howard Hughes Medical Institute, NYU Neuroscience Institute, Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016, USA
| | - Byrappa Venkatesh
- Comparative Genomics Laboratory, Institute of Molecular and Cell Biology, A(∗)STAR, Biopolis, Singapore 138673, Singapore; Department of Paediatrics, Yong Loo Lin School of Medicine, National University of Singapore, Singapore 119228, Singapore
| | - Denis Duboule
- Department of Genetics and Evolution, University of Geneva, Sciences III, Quai Ernest-Ansermet 30, 1211 Geneva 4, Switzerland; School of Life Sciences, Ecole Polytechnique Fédérale, 1015 Lausanne, Switzerland
| | - Jeremy S Dasen
- Howard Hughes Medical Institute, NYU Neuroscience Institute, Department of Neuroscience and Physiology, New York University School of Medicine, New York, NY 10016, USA.
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Abstract
All muscle movements, including breathing, walking, and fine motor skills rely on the function of the spinal motor neuron to transmit signals from the brain to individual muscle groups. Loss of spinal motor neuron function underlies several neurological disorders for which treatment has been hampered by the inability to obtain sufficient quantities of primary motor neurons to perform mechanistic studies or drug screens. Progress towards overcoming this challenge has been achieved through the synthesis of developmental biology paradigms and advances in stem cell and reprogramming technology, which allow the production of motor neurons in vitro. In this Primer, we discuss how the logic of spinal motor neuron development has been applied to allow generation of motor neurons either from pluripotent stem cells by directed differentiation and transcriptional programming, or from somatic cells by direct lineage conversion. Finally, we discuss methods to evaluate the molecular and functional properties of motor neurons generated through each of these techniques.
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Affiliation(s)
- Brandi N Davis-Dusenbery
- Harvard Stem Cell Institute, Department of Stem Cell and Regenerative Biology, Harvard University, Cambridge, MA 02138, USA
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Francius C, Clotman F. Generating spinal motor neuron diversity: a long quest for neuronal identity. Cell Mol Life Sci 2014; 71:813-29. [PMID: 23765105 PMCID: PMC11113339 DOI: 10.1007/s00018-013-1398-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Revised: 05/30/2013] [Accepted: 05/31/2013] [Indexed: 03/26/2023]
Abstract
Understanding how thousands of different neuronal types are generated in the CNS constitutes a major challenge for developmental neurobiologists and is a prerequisite before considering cell or gene therapies of nervous lesions or pathologies. During embryonic development, spinal motor neurons (MNs) segregate into distinct subpopulations that display specific characteristics and properties including molecular identity, migration pattern, allocation to specific motor columns, and innervation of defined target. Because of the facility to correlate these different characteristics, the diversification of spinal MNs has become the model of choice for studying the molecular and cellular mechanisms underlying the generation of multiple neuronal populations in the developing CNS. Therefore, how spinal motor neuron subpopulations are produced during development has been extensively studied during the last two decades. In this review article, we will provide a comprehensive overview of the genetic and molecular mechanisms that contribute to the diversification of spinal MNs.
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Affiliation(s)
- Cédric Francius
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, 55 Avenue Hippocrate, Box (B1.55.11), 1200 Brussels, Belgium
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, 55 Avenue Hippocrate, Box (B1.55.11), 1200 Brussels, Belgium
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Bhatlekar S, Addya S, Salunek M, Orr CR, Surrey S, McKenzie S, Fields JZ, Boman BM. Identification of a developmental gene expression signature, including HOX genes, for the normal human colonic crypt stem cell niche: overexpression of the signature parallels stem cell overpopulation during colon tumorigenesis. Stem Cells Dev 2013; 23:167-79. [PMID: 23980595 DOI: 10.1089/scd.2013.0039] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Our goal was to identify a unique gene expression signature for human colonic stem cells (SCs). Accordingly, we determined the gene expression pattern for a known SC-enriched region--the crypt bottom. Colonic crypts and isolated crypt subsections (top, middle, and bottom) were purified from fresh, normal, human, surgical specimens. We then used an innovative strategy that used two-color microarrays (∼18,500 genes) to compare gene expression in the crypt bottom with expression in the other crypt subsections (middle or top). Array results were validated by PCR and immunostaining. About 25% of genes analyzed were expressed in crypts: 88 preferentially in the bottom, 68 in the middle, and 131 in the top. Among genes upregulated in the bottom, ∼30% were classified as growth and/or developmental genes including several in the PI3 kinase pathway, a six-transmembrane protein STAMP1, and two homeobox (HOXA4, HOXD10) genes. qPCR and immunostaining validated that HOXA4 and HOXD10 are selectively expressed in the normal crypt bottom and are overexpressed in colon carcinomas (CRCs). Immunostaining showed that HOXA4 and HOXD10 are co-expressed with the SC markers CD166 and ALDH1 in cells at the normal crypt bottom, and the number of these co-expressing cells is increased in CRCs. Thus, our findings show that these two HOX genes are selectively expressed in colonic SCs and that HOX overexpression in CRCs parallels the SC overpopulation that occurs during CRC development. Our study suggests that developmental genes play key roles in the maintenance of normal SCs and crypt renewal, and contribute to the SC overpopulation that drives colon tumorigenesis.
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Affiliation(s)
- Seema Bhatlekar
- 1 Center for Translational Cancer Research, Helen F. Graham Cancer Center and Research Institute, University of Delaware , Newark, Delaware
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Philippidou P, Dasen JS. Hox genes: choreographers in neural development, architects of circuit organization. Neuron 2013; 80:12-34. [PMID: 24094100 DOI: 10.1016/j.neuron.2013.09.020] [Citation(s) in RCA: 284] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The neural circuits governing vital behaviors, such as respiration and locomotion, are comprised of discrete neuronal populations residing within the brainstem and spinal cord. Work over the past decade has provided a fairly comprehensive understanding of the developmental pathways that determine the identity of major neuronal classes within the neural tube. However, the steps through which neurons acquire the subtype diversities necessary for their incorporation into a particular circuit are still poorly defined. Studies on the specification of motor neurons indicate that the large family of Hox transcription factors has a key role in generating the subtypes required for selective muscle innervation. There is also emerging evidence that Hox genes function in multiple neuronal classes to shape synaptic specificity during development, suggesting a broader role in circuit assembly. This Review highlights the functions and mechanisms of Hox gene networks and their multifaceted roles during neuronal specification and connectivity.
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Affiliation(s)
- Polyxeni Philippidou
- Howard Hughes Medical Institute, NYU Neuroscience Institute, Department of Neuroscience and Physiology, NYU School of Medicine, New York, NY 10016, USA.
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Regional and segmental differences in the embryonic expression of a putative leech Hox gene, Lox2, by central neurons immunoreactive to FMRFamide-like neuropeptides. INVERTEBRATE NEUROSCIENCE 2013; 14:51-8. [PMID: 23958799 DOI: 10.1007/s10158-013-0161-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2013] [Accepted: 08/06/2013] [Indexed: 10/26/2022]
Abstract
We performed immunofluorescence experiments using a rat polyclonal antibody on formaldehyde-fixed whole-mount embryos to characterize the expression of a putative leech Hox gene, Lox2, during embryonic development. The main goal was to determine whether the differentiation of subsets of FMRFamide-like immunoreactive (FLI) neurons coincide with the expression domain of Lox2. The earliest expression of Lox2 was detected in relatively large, prominent nuclei in the posterior region at embryonic day 4, a very early stage. Lox2 expression was also detected in subsets of central neurons (neurons located in the CNS) located in midbody ganglia 6 (M6)-M21. In addition, Lox2 was expressed by a number of segment-specific and segmentally repeated central FLI neurons. Lox2-positive FLI neurons of interest included some of those previously identified: the rostral most ventral (RMV) neurons, the circular ventral (CV) neurons, and cell 261. The paired RMVs, which are located in all midbody ganglia, expressed Lox2 only in M7-M19. The CV neurons, specialized motor neurons that innervate the circular ventral muscles of the body wall, expressed Lox2 in M7-M19. The putative cell 261 expressed Lox2 in M7-M12, where Lox1 is also expressed. FMRFamide staining in putative segmental homologs of cell 261 was not detected in other segmental ganglia. Our results suggest a role for Lox2 in very early embryonic development (before the formation of the CNS), and in the differentiation of segmentally repeated and region-specific FLI neurons.
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Mazzoni EO, Mahony S, Peljto M, Patel T, Thornton SR, McCuine S, Reeder C, Boyer LA, Young RA, Gifford DK, Wichterle H. Saltatory remodeling of Hox chromatin in response to rostrocaudal patterning signals. Nat Neurosci 2013; 16:1191-1198. [PMID: 23955559 PMCID: PMC3799941 DOI: 10.1038/nn.3490] [Citation(s) in RCA: 111] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2013] [Accepted: 07/10/2013] [Indexed: 12/16/2022]
Abstract
Hox genes controlling motor neuron subtype identity are expressed in rostro-caudal patterns that are spatially and temporally collinear with their chromosomal organization. Here we demonstrate that Hox chromatin is subdivided into discrete domains, controlled by rostro-caudal patterning signals that trigger rapid, domain-wide clearance of repressive H3K27me3 Polycomb modifications. Treatment of differentiating mouse neural progenitors with retinoic acid (RA) leads to activation and binding of RA receptors (RARs) to Hox1-5 chromatin domains, followed by a rapid domain-wide removal of H3K27me3 and acquisition of cervical spinal identity. Wnt and FGF signals induce expression of Cdx2 transcription factor that binds and clears H3K27me3 from Hox1-9 chromatin domains, leading to specification of brachial/thoracic spinal identity. We propose that rapid clearance of repressive modifications in response to transient patterning signals encodes global rostro-caudal neural identity and that maintenance of these chromatin domains ensures transmission of the positional identity to postmitotic motor neurons later in development.
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Affiliation(s)
- Esteban O Mazzoni
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA.,Department of Biology, New York University. 100 Washington Square East, New York, NY 10003, USA
| | - Shaun Mahony
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA.,Department of Biochemistry & Molecular Biology, Center for Eukaryotic Gene Regulation, The Pennsylvania State University, University Park, PA 16802
| | - Mirza Peljto
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
| | - Tulsi Patel
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
| | - Seraphim R Thornton
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Scott McCuine
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - Christopher Reeder
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA
| | - Laurie A Boyer
- Department of Biology, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research, 9 Cambridge Center, Cambridge, MA 02142, USA
| | - David K Gifford
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, 32 Vassar Street, Cambridge, MA 02139, USA
| | - Hynek Wichterle
- Departments of Pathology and Cell Biology, Neurology, and Neuroscience, Center for Motor Neuron Biology and Disease, Columbia Stem Cell Initiative, Columbia University Medical Center, 630 W 168 Street, New York, NY 10032, USA
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Francius C, Harris A, Rucchin V, Hendricks TJ, Stam FJ, Barber M, Kurek D, Grosveld FG, Pierani A, Goulding M, Clotman F. Identification of multiple subsets of ventral interneurons and differential distribution along the rostrocaudal axis of the developing spinal cord. PLoS One 2013; 8:e70325. [PMID: 23967072 PMCID: PMC3744532 DOI: 10.1371/journal.pone.0070325] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2013] [Accepted: 06/17/2013] [Indexed: 01/06/2023] Open
Abstract
The spinal cord contains neuronal circuits termed Central Pattern Generators (CPGs) that coordinate rhythmic motor activities. CPG circuits consist of motor neurons and multiple interneuron cell types, many of which are derived from four distinct cardinal classes of ventral interneurons, called V0, V1, V2 and V3. While significant progress has been made on elucidating the molecular and genetic mechanisms that control ventral interneuron differentiation, little is known about their distribution along the antero-posterior axis of the spinal cord and their diversification. Here, we report that V0, V1 and V2 interneurons exhibit distinct organizational patterns at brachial, thoracic and lumbar levels of the developing spinal cord. In addition, we demonstrate that each cardinal class of ventral interneurons can be subdivided into several subsets according to the combinatorial expression of different sets of transcription factors, and that these subsets are differentially distributed along the rostrocaudal axis of the spinal cord. This comprehensive molecular profiling of ventral interneurons provides an important resource for investigating neuronal diversification in the developing spinal cord and for understanding the contribution of specific interneuron subsets on CPG circuits and motor control.
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Affiliation(s)
- Cédric Francius
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Audrey Harris
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Vincent Rucchin
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
| | - Timothy J. Hendricks
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Floor J. Stam
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Melissa Barber
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Dorota Kurek
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Frank G. Grosveld
- Erasmus MC Stem Cell Institute, Department of Cell Biology, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Alessandra Pierani
- CNRS UMR 7592, Institut Jacques Monod, Université Paris Diderot, Sorbonne Paris Cité, Paris, France
| | - Martyn Goulding
- Molecular Neurobiology Laboratory, The Salk Institute for Biological Studies, La Jolla, California, United States of America
| | - Frédéric Clotman
- Université catholique de Louvain, Institute of Neuroscience, Laboratory of Neural Differentiation, Brussels, Belgium
- * E-mail:
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Misra M, Sours E, Lance-Jones C. Hox transcription factors influence motoneuron identity through the integrated actions of both homeodomain and non-homeodomain regions. Dev Dyn 2013; 241:718-31. [PMID: 22411553 DOI: 10.1002/dvdy.23763] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
BACKGROUND Hox transcription factors play a critical role in the specification of motoneuron subtypes within the spinal cord. Our previous work showed that two orthologous members of this family, Hoxd10 and Hoxd11, exert opposing effects on motoneuron development in the lumbosacral (LS) spinal cord of the embryonic chick: Hoxd10 promotes the development of lateral motoneuron subtypes that project to dorsal limb muscles, while Hoxd11 represses the development of lateral subtypes in favor of medial subtypes that innervate ventral limb muscles and axial muscles. The striking degree of homology between the DNA-binding homeodomains of Hoxd10 and Hoxd11 suggested that non-homeodomain regions mediate their divergent effects. In the present study, we investigate the relative contributions of homeodomain and non-homeodomain regions of Hoxd10 and Hoxd11 to motoneuron specification. RESULTS Using in ovo electroporation to express chimeric and mutant constructs in LS motoneurons, we find that both the homeodomain and non-homeodomain regions of Hoxd10 are necessary to specify lateral motoneurons. In contrast, non-homeodomain regions of Hoxd11 are sufficient to repress lateral motoneuron fates in favor of medial fates. CONCLUSIONS Together, our data demonstrate that even closely related Hox orthologues rely on distinct combinations of homeodomain-dependent and -independent mechanisms to specify motoneuron identity.
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Affiliation(s)
- Mala Misra
- Department of Neurobiology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania 15261, USA
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50
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Lacombe J, Hanley O, Jung H, Philippidou P, Surmeli G, Grinstein J, Dasen JS. Genetic and functional modularity of Hox activities in the specification of limb-innervating motor neurons. PLoS Genet 2013; 9:e1003184. [PMID: 23359544 PMCID: PMC3554521 DOI: 10.1371/journal.pgen.1003184] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Accepted: 11/06/2012] [Indexed: 11/18/2022] Open
Abstract
A critical step in the assembly of the neural circuits that control tetrapod locomotion is the specification of the lateral motor column (LMC), a diverse motor neuron population targeting limb musculature. Hox6 paralog group genes have been implicated as key determinants of LMC fate at forelimb levels of the spinal cord, through their ability to promote expression of the LMC-restricted genes Foxp1 and Raldh2 and to suppress thoracic fates through exclusion of Hoxc9. The specific roles and mechanisms of Hox6 gene function in LMC neurons, however, are not known. We show that Hox6 genes are critical for diverse facets of LMC identity and define motifs required for their in vivo specificities. Although Hox6 genes are necessary for generating the appropriate number of LMC neurons, they are not absolutely required for the induction of forelimb LMC molecular determinants. In the absence of Hox6 activity, LMC identity appears to be preserved through a diverse array of Hox5–Hox8 paralogs, which are sufficient to reprogram thoracic motor neurons to an LMC fate. In contrast to the apparently permissive Hox inputs to early LMC gene programs, individual Hox genes, such as Hoxc6, have specific roles in promoting motor neuron pool diversity within the LMC. Dissection of motifs required for Hox in vivo specificities reveals that either cross-repressive interactions or cooperativity with Pbx cofactors are sufficient to induce LMC identity, with the N-terminus capable of promoting columnar, but not pool, identity when transferred to a heterologous homeodomain. These results indicate that Hox proteins orchestrate diverse aspects of cell fate specification through both the convergent regulation of gene programs regulated by many paralogs and also more restricted actions encoded through specificity determinants in the N-terminus. Coordinated motor behaviors—as complex as playing a musical instrument or as simple as walking—rely on the ability of motor neurons within the spinal cord to navigate towards and establish specific connections with muscles in the limbs. The establishment of connections between motor neurons and limb muscles is mediated through the actions of genes encoding Hox proteins, a large family of transcription factors conserved amongst all metazoans. However, the specific requirements for Hox genes in motor neuron specification and patterns of muscle connectivity are poorly understood. We have found that members of the Hox6 gene paralog group (Hoxa6, Hoxc6, and Hoxb6) contribute to diverse aspects of motor neuron subtype differentiation. Hox6 gene activity is required during two critical phases of motor neuron development: first as motor axons select a trajectory toward the forelimb and second as they choose specific muscles to innervate. At the molecular level, these two functions are encoded by distinct peptide domains within Hox proteins. This work indicates that Hox proteins execute their critical functions in motor neurons through intrinsic modules that confer distinct specificities and that these activities are central in the genetic network required for motor neuron differentiation.
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Affiliation(s)
- Julie Lacombe
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
| | - Olivia Hanley
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
| | - Heekyung Jung
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
| | - Polyxeni Philippidou
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
| | - Gulsen Surmeli
- Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York, United States of America
| | - Jonathan Grinstein
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
| | - Jeremy S. Dasen
- Smilow Neuroscience Program, Department of Physiology and Neuroscience, Howard Hughes Medical Institute, NYU School of Medicine, New York, New York, United States of America
- * E-mail:
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