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Jędrychowska J, Vardanyan V, Wieczor M, Marciniak A, Czub J, Amini R, Jain R, Shen H, Choi H, Kuznicki J, Korzh V. Mutant analysis of Kcng4b reveals how the different functional states of the voltage-gated potassium channel regulate ear development. Dev Biol 2024; 513:50-62. [PMID: 38492873 DOI: 10.1016/j.ydbio.2024.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 03/18/2024]
Abstract
The voltage gated (Kv) slow-inactivating delayed rectifier channel regulates the development of hollow organs of the zebrafish. The functional channel consists of the tetramer of electrically active Kcnb1 (Kv2.1) subunits and Kcng4b (Kv6.4) modulatory or electrically silent subunits. The two mutations in zebrafish kcng4b gene - kcng4b-C1 and kcng4b-C2 (Gasanov et al., 2021) - have been studied during ear development using electrophysiology, developmental biology and in silico structural modelling. kcng4b-C1 mutation causes a C-terminal truncation characterized by mild Kcng4b loss-of-function (LOF) manifested by failure of kinocilia to extend and formation of ectopic otoliths. In contrast, the kcng4b-C2-/- mutation causes the C-terminal domain to elongate and the ectopic seventh transmembrane (TM) domain to form, converting the intracellular C-terminus to an extracellular one. Kcng4b-C2 acts as a Kcng4b gain-of-function (GOF) allele. Otoliths fail to develop and kinocilia are reduced in kcng4b-C2-/-. These results show that different mutations of the silent subunit Kcng4 can affect the activity of the Kv channel and cause a wide range of developmental defects.
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Affiliation(s)
- Justyna Jędrychowska
- International Institute of Molecular and Cell Biology in Warsaw, Poland; Department of Genetics, Institute of Physiology and Pathology of Hearing, Warsaw, Poland
| | - Vitya Vardanyan
- Institute of Molecular Biology, Armenian Academy of Sciences, Yerevan, Armenia
| | - Milosz Wieczor
- Department of Physical Chemistry, Gdansk University of Technology, Gdansk, Poland
| | - Antoni Marciniak
- Department of Physical Chemistry, Gdansk University of Technology, Gdansk, Poland
| | - Jacek Czub
- Department of Physical Chemistry, Gdansk University of Technology, Gdansk, Poland
| | - Razieh Amini
- International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Ruchi Jain
- International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Hongyuan Shen
- Singapore Nuclear Research and Safety Initiative, National University of Singapore, Singapore
| | - Hyungwon Choi
- Cardiovascular Research Institute, National University Health Sciences, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jacek Kuznicki
- International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Vladimir Korzh
- International Institute of Molecular and Cell Biology in Warsaw, Poland.
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2
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Zizioli D, Quiros-Roldan E, Ferretti S, Mignani L, Tiecco G, Monti E, Castelli F, Zanella I. Dolutegravir and Folic Acid Interaction during Neural System Development in Zebrafish Embryos. Int J Mol Sci 2024; 25:4640. [PMID: 38731859 PMCID: PMC11083492 DOI: 10.3390/ijms25094640] [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: 02/20/2024] [Revised: 04/04/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024] Open
Abstract
Dolutegravir (DTG) is one of the most prescribed antiretroviral drugs for treating people with HIV infection, including women of child-bearing potential or pregnant. Nonetheless, neuropsychiatric symptoms are frequently reported. Early reports suggested that, probably in relation to folic acid (FA) shortage, DTG may induce neural tube defects in infants born to women taking the drug during pregnancy. Subsequent reports did not definitively confirm these findings. Recent studies in animal models have highlighted the association between DTG exposure in utero and congenital anomalies, and an increased risk of neurologic abnormalities in children exposed during in utero life has been reported. Underlying mechanisms for DTG-related neurologic symptoms and congenital anomalies are not fully understood. We aimed to deepen our knowledge on the neurodevelopmental effects of DTG exposure and further explore the protective role of FA by the use of zebrafish embryos. We treated embryos at 4 and up to 144 h post fertilization (hpf) with a subtherapeutic DTG concentration (1 μM) and observed the disruption of the anterior-posterior axis and several morphological malformations in the developing brain that were both prevented by pre-exposure (2 hpf) and rescued by post-exposure (10 hpf) with FA. By whole-mount in situ hybridization with riboprobes for genes that are crucial during the early phases of neurodevelopment (ntl, pax2a, ngn1, neurod1) and by in vivo visualization of the transgenic Tg(ngn1:EGFP) zebrafish line, we found that DTG induced severe neurodevelopmental defects over time in most regions of the nervous system (notochord, midbrain-hindbrain boundary, eye, forebrain, midbrain, hindbrain, spinal cord) that were mostly but not completely rescued by FA supplementation. Of note, we observed the disruption of ngn1 expression in the dopaminergic regions of the developing forebrain, spinal cord neurons and spinal motor neuron projections, with the depletion of the tyrosine hydroxylase (TH)+ dopaminergic neurons of the dorsal diencephalon and the strong reduction in larvae locomotion. Our study further supports previous evidence that DTG can interfere with FA pathways in the developing brain but also provides new insights regarding the mechanisms involved in the increased risk of DTG-associated fetal neurodevelopmental defects and adverse neurologic outcomes in in utero exposed children, suggesting the impairment of dopaminergic pathways.
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Affiliation(s)
- Daniela Zizioli
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (D.Z.); (S.F.); (L.M.); (E.M.); (I.Z.)
| | - Eugenia Quiros-Roldan
- Unit of Infectious and Tropical Diseases, Department of Clinical and Experimental Sciences, University of Brescia and ASST Spedali Civili di Brescia, 25123 Brescia, Italy; (G.T.); (F.C.)
| | - Sara Ferretti
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (D.Z.); (S.F.); (L.M.); (E.M.); (I.Z.)
| | - Luca Mignani
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (D.Z.); (S.F.); (L.M.); (E.M.); (I.Z.)
| | - Giorgio Tiecco
- Unit of Infectious and Tropical Diseases, Department of Clinical and Experimental Sciences, University of Brescia and ASST Spedali Civili di Brescia, 25123 Brescia, Italy; (G.T.); (F.C.)
| | - Eugenio Monti
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (D.Z.); (S.F.); (L.M.); (E.M.); (I.Z.)
| | - Francesco Castelli
- Unit of Infectious and Tropical Diseases, Department of Clinical and Experimental Sciences, University of Brescia and ASST Spedali Civili di Brescia, 25123 Brescia, Italy; (G.T.); (F.C.)
| | - Isabella Zanella
- Department of Molecular and Translational Medicine, University of Brescia, 25123 Brescia, Italy; (D.Z.); (S.F.); (L.M.); (E.M.); (I.Z.)
- Cytogenetics and Molecular Genetics Laboratory, Diagnostic Department, ASST Spedali Civili di Brescia, 25123 Brescia, Italy
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3
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Cao X, Xie W, Feng M, Chen J, Zhang J, Luo J, Wang Y. Nanoplastic Exposure Mediates Neurodevelopmental Toxicity by Activating the Oxidative Stress Response in Zebrafish ( Danio rerio). ACS OMEGA 2024; 9:16508-16518. [PMID: 38617687 PMCID: PMC11007712 DOI: 10.1021/acsomega.4c00231] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 03/18/2024] [Accepted: 03/21/2024] [Indexed: 04/16/2024]
Abstract
The global accumulation and adverse effects of nanoplastics (NPs) are a growing concern for the environment and human health. In recent years, more and more studies have begun to focus on the toxicity of plastic particles for early animal development. Different particle sizes of plastic particles have different toxicities to biological development. Nevertheless, the potential toxicological effects of 20 nm NPs, especially on neurodevelopment, have not been well investigated. In this paper, we used fluorescence microscopy to determine neurotoxicity in zebrafish at different concentrations of NPs. Moreover, the behavioral analysis demonstrated that NPs induced abnormal behavior of zebrafish. The results revealed developmental defects in zebrafish embryos after exposure to different concentrations (0, 0.3, 3, and 9 mg/L) of NPs. The morphological deformities, including abnormal body length and the rates of heart, survival, and hatching, were induced after NP exposure in zebrafish embryos. In addition, the development of primary motor neurons was observed the inhibitory effects of NPs on the length, occurrence, and development of primary motor neurons in Tg(hb9:GFP). Quantitative polymerase chain reaction analysis suggested that exposure to NPs significantly affects the expression of the genes involved in the occurrence and differentiation of primary motor neurons in zebrafish. Furthermore, the indicators associated with oxidative stress and apoptosis were found to be modified in zebrafish embryos at 24 and 48 h following exposure to NPs. Our findings demonstrated that NPs could cause toxicity in primary motor neurons by activating the oxidative stress response and inducing apoptosis, consequently impairing motor performance.
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Affiliation(s)
- Xiaoqian Cao
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Wenjie Xie
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
- Engineering
Research Center of Key Technique for Biotherapy of Guangdong Province, Shantou University Medical College, Shantou 515041, People’s Republic of China
| | - Meilan Feng
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Juntao Chen
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Jiannan Zhang
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
| | - Juanjuan Luo
- Engineering
Research Center of Key Technique for Biotherapy of Guangdong Province, Shantou University Medical College, Shantou 515041, People’s Republic of China
| | - Yajun Wang
- Key
Laboratory of Bio-resources and Eco-environment of Ministry of Education,
College of Life Science, Sichuan University, Chengdu 610065, People’s Republic of China
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4
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Yuikawa T, Sato T, Ikeda M, Tsuruoka M, Yasuda K, Sato Y, Nasu K, Yamasu K. Elongation of the developing spinal cord is driven by Oct4-type transcription factor-mediated regulation of retinoic acid signaling in zebrafish embryos. Dev Dyn 2024; 253:404-422. [PMID: 37850839 DOI: 10.1002/dvdy.666] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Revised: 10/04/2023] [Accepted: 10/05/2023] [Indexed: 10/19/2023] Open
Abstract
BACKGROUND Elongation of the spinal cord is dependent on neural development from neuromesodermal progenitors in the tail bud. We previously showed the involvement of the Oct4-type gene, pou5f3, in this process in zebrafish mainly by dominant-interference gene induction, but, to compensate for the limitation of this transgene approach, mutant analysis was indispensable. pou5f3 involvement in the signaling pathways was another unsolved question. RESULTS We examined the phenotypes of pou5f3 mutants and the effects of Pou5f3 activation by the tamoxifen-ERT2 system in the posterior neural tube, together confirming the involvement of pou5f3. The reporter assays using P19 cells implicated tail bud-related transcription factors in pou5f3 expression. Regulation of tail bud development by retinoic acid (RA) signaling was confirmed by treatment of embryos with RA and the synthesis inhibitor, and in vitro reporter assays further showed that RA signaling regulated pou5f3 expression. Importantly, the expression of the RA degradation enzyme gene, cyp26a1, was down-regulated in embryos with disrupted pou5f3 activity. CONCLUSIONS The involvement of pou5f3 in spinal cord extension was supported by using mutants and the gain-of-function approach. Our findings further suggest that pou5f3 regulates the RA level, contributing to neurogenesis in the posterior neural tube.
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Affiliation(s)
- Tatsuya Yuikawa
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Takehisa Sato
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Masaaki Ikeda
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Momo Tsuruoka
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Kaede Yasuda
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Yuto Sato
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Kouhei Nasu
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
| | - Kyo Yamasu
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Saitama, Japan
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5
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Zhao L, Fong SH, Yang Q, Jiang YJ, Korzh V, Liou YC. The prolyl isomerase Pin1 stabilizes NeuroD during differentiation of mechanoreceptors. Front Cell Dev Biol 2023; 11:1225128. [PMID: 37791075 PMCID: PMC10543749 DOI: 10.3389/fcell.2023.1225128] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 08/11/2023] [Indexed: 10/05/2023] Open
Abstract
The peptidyl prolyl cis-trans isomerase Pin1 plays vital roles in diverse cellular processes and pathological conditions. NeuroD is a differentiation and survival factor for a subset of neurons and pancreatic endocrine cells. Although multiple phosphorylation events are known to be crucial for NeuroD function, their mechanisms remain elusive. In this study, we demonstrate that zebrafish embryos deficient in Pin1 displayed phenotypes resembling those associated with NeuroD depletion, characterized by defects in formation of mechanosensory hair cells. Furthermore, zebrafish Pin1 interacts with NeuroD in a phosphorylation-dependent manner. In Pin1-deficient cell lines, NeuroD is rapidly degraded. However, the protein stability of NeuroD is restored upon overexpression of Pin1. These findings suggest that Pin1 functionally regulates NeuroD protein levels by post-phosphorylation cis-trans isomerization during neuronal specification.
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Affiliation(s)
- Liqun Zhao
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Steven H. Fong
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
- Genes and Development Division, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Qiaoyun Yang
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
| | - Yun-Jin Jiang
- Institute of Molecular and Genomic Medicine, National Health Research Institutes, Zhunan, Taiwan
| | - Vladimir Korzh
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
- Genes and Development Division, Institute of Molecular and Cell Biology, Agency for Science, Technology and Research (A-STAR), Singapore, Singapore
| | - Yih-Cherng Liou
- Department of Biological Sciences, Faculty of Science, National University of Singapore, Singapore, Singapore
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6
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Mignani L, Facchinello N, Varinelli M, Massardi E, Tiso N, Ravelli C, Mitola S, Schu P, Monti E, Finazzi D, Borsani G, Zizioli D. Deficiency of AP1 Complex Ap1g1 in Zebrafish Model Led to Perturbation of Neurodevelopment, Female and Male Fertility; New Insight to Understand Adaptinopathies. Int J Mol Sci 2023; 24:ijms24087108. [PMID: 37108275 PMCID: PMC10138411 DOI: 10.3390/ijms24087108] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 04/03/2023] [Accepted: 04/03/2023] [Indexed: 04/29/2023] Open
Abstract
In vertebrates, two homologous heterotetrameric AP1 complexes regulate the intracellular protein sorting via vesicles. AP-1 complexes are ubiquitously expressed and are composed of four different subunits: γ, β1, μ1 and σ1. Two different complexes are present in eukaryotic cells, AP1G1 (contains γ1 subunit) and AP1G2 (contains γ2 subunit); both are indispensable for development. One additional tissue-specific isoform exists for μ1A, the polarized epithelial cells specific to μ1B; two additional tissue-specific isoforms exist for σ1A: σ1B and σ1C. Both AP1 complexes fulfil specific functions at the trans-Golgi network and endosomes. The use of different animal models demonstrated their crucial role in the development of multicellular organisms and the specification of neuronal and epithelial cells. Ap1g1 (γ1) knockout mice cease development at the blastocyst stage, while Ap1m1 (μ1A) knockouts cease during mid-organogenesis. A growing number of human diseases have been associated with mutations in genes encoding for the subunits of adaptor protein complexes. Recently, a new class of neurocutaneous and neurometabolic disorders affecting intracellular vesicular traffic have been referred to as adaptinopathies. To better understand the functional role of AP1G1 in adaptinopathies, we generated a zebrafish ap1g1 knockout using CRISPR/Cas9 genome editing. Zebrafish ap1g1 knockout embryos cease their development at the blastula stage. Interestingly, heterozygous females and males have reduced fertility and showed morphological alterations in the brain, gonads and intestinal epithelium. An analysis of mRNA profiles of different marker proteins and altered tissue morphologies revealed dysregulated cadherin-mediated cell adhesion. These data demonstrate that the zebrafish model organism enables us to study the molecular details of adaptinopathies and thus also develop treatment strategies.
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Affiliation(s)
- Luca Mignani
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Nicola Facchinello
- Neuroscience Institute, Italian Research Council (CNR), 35131 Padova, Italy
| | - Marco Varinelli
- Istituto di Ricerche Farmacologiche Mario Negri IRCCS, 24126 Bergamo, Italy
| | - Elena Massardi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Natascia Tiso
- Department of Biology, University of Padova, Via Ugo Bassi 58/B, 35131 Padova, Italy
| | - Cosetta Ravelli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Stefania Mitola
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
- CN3 "Sviluppo di Terapia Genica e Farmaci con Tecnologia ad RNA", 25123 Brescia, Italy
| | - Peter Schu
- Department of Cellular Biochemistry, University Medical Center, Georg-August University, Humboldtallee 23, 37073 Gottingen, Germany
| | - Eugenio Monti
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Dario Finazzi
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
- Clinical Chemistry Laboratory, ASST Spedali Civili di Brescia, 25123 Brescia, Italy
| | - Giuseppe Borsani
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
| | - Daniela Zizioli
- Department of Molecular and Translational Medicine, University of Brescia, Viale Europa, 11, 25123 Brescia, Italy
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7
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Cabotegravir Exposure of Zebrafish ( Danio rerio) Embryos Impacts on Neurodevelopment and Behavior. Int J Mol Sci 2023; 24:ijms24031994. [PMID: 36768311 PMCID: PMC9916638 DOI: 10.3390/ijms24031994] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/20/2023] Open
Abstract
As most new medications, Cabotegravir (CAB) was recently approved as an antiretroviral treatment of HIV infection without in-depth safety information on in utero exposure. Although no developmental toxicity in rats and rabbits was reported, recent studies demonstrated that CAB decreases pluripotency of human embryonic stem cells. CAB exposure effects during development were assessed in zebrafish embryos by the Fish Embryo Toxicity test after exposure at subtherapeutic concentrations up to 25× the human Cmax. Larvae behavior was assessed by the light-dark locomotion test. The expression of factors involved in neurogenesis was evaluated by whole-mount in situ hybridization. CAB did not cause gross morphological defects at low doses, although pericardial edema, uninflated swim bladder, decreased heartbeats, growth delay, and decreased hatching rate were observed at the highest concentrations. Decreased locomotion was observed even at the subtherapeutic dose, suggesting alterations of nervous system integrity. This hypothesis was supported by the observation of decreased expression of crucial factors involved in early neuronal differentiation in diencephalic and telencephalic dopaminergic areas, midbrain/hindbrain boundary, and craniofacial ganglia. These findings support CAB effects on neurogenesis in zebrafish embryos and suggest long-term follow-up of exposed infants to provide data on drug safety during pregnancy.
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Identification of the Time Period during Which BMP Signaling Regulates Proliferation of Neural Progenitor Cells in Zebrafish. Int J Mol Sci 2023; 24:ijms24021733. [PMID: 36675251 PMCID: PMC9863262 DOI: 10.3390/ijms24021733] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/06/2023] [Accepted: 01/13/2023] [Indexed: 01/18/2023] Open
Abstract
Bone morphogenetic protein (BMP) signaling regulates neural induction, neuronal specification, and neuronal differentiation. However, the role of BMP signaling in neural progenitors remains unclear. This is because interruption of BMP signaling before or during neural induction causes severe effects on subsequent neural developmental processes. To examine the role of BMP signaling in the development of neural progenitors in zebrafish, we bypassed the effect of BMP signaling on neural induction and suppressed BMP signaling at different time points during gastrulation using a temporally controlled transgenic line carrying a dominant-negative form of Bmp receptor type 1aa and a chemical inhibitor of BMP signaling, DMH1. Inhibiting BMP signaling from 8 hpf could bypass BMP regulation on neural induction, induce the number of proliferating neural progenitors, and reduce the number of neuronal precursors. Inhibiting BMP signaling upregulates the expression of the Notch downstream gene hairy/E(spl)-related 2 (her2). Inhibiting Notch signaling or knocking down the Her2 function reduced neural progenitor proliferation, whereas inactivating BMP signaling in Notch-Her2 deficient background restored the number of proliferating neural progenitors. These results reveal the time window for the proliferation of neural progenitors during zebrafish development and a fine balance between BMP and Notch signaling in regulating the proliferation of neural progenitor cells.
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Yu H, Zhang J, Chen Y, Chen J, Qiu Y, Zhao Y, Li H, Xia S, Chen S, Zhu J. The adverse effects of fluxapyroxad on the neurodevelopment of zebrafish embryos. CHEMOSPHERE 2022; 307:135751. [PMID: 35863420 DOI: 10.1016/j.chemosphere.2022.135751] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2022] [Revised: 07/13/2022] [Accepted: 07/14/2022] [Indexed: 06/15/2023]
Abstract
Fluxapyroxad (Flu), one of the succinate dehydrogenase-inhibited (SDHI) fungicides, has been extensively used in crop fungal disease control. Despite its increasing use in modern agriculture and long-term retention in the environment, the potentially toxic effects of Flu in vivo, especially on neurodevelopment, remain under-evaluated. In this study, zebrafish embryos were exposed to Flu at concentrations of 0.5, 0.75, and 1 mg/L for 96 h to evaluate the neurotoxicity of Flu. The results showed that Flu caused concentration-dependent malformations, including shorter body length, smaller head and eyes, and yolk sac edema. After exposure to Flu, larval zebrafish exhibited severe motor aberrations. Flu at a concentration of 1 mg/L significantly decreased dopamine level and notably altered acetylcholinesterase (AChE) activity and acetylcholine (ACh) content. Abnormal central nervous system (CNS) neurogenesis and disordered motor neuron development were observed in Tg (HUC-GFP) and Tg (hb9-GFP) zebrafish in Flu-treated groups. The expression of key genes involved in neurotransmission and neurodevelopment further proved that Flu impaired the zebrafish nervous system. This work contributes to our understanding of the neurotoxic effects and mechanisms induced by Flu in zebrafish and may help us take precautions against the neurotoxicity of Flu.
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Affiliation(s)
- Huilin Yu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Junhui Zhang
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Yinghong Chen
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Juan Chen
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Yang Qiu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Yan Zhao
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Honghao Li
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Shengyao Xia
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China
| | - Shiguo Chen
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
| | - Jiajin Zhu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, 310058, Zhejiang, China.
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10
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Bi-Allelic Mutations in Zebrafish pank2 Gene Lead to Testicular Atrophy and Perturbed Behavior without Signs of Neurodegeneration. Int J Mol Sci 2022; 23:ijms232112914. [DOI: 10.3390/ijms232112914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 10/01/2022] [Accepted: 10/22/2022] [Indexed: 11/17/2022] Open
Abstract
Coenzyme A (CoA) is an essential cofactor in all living organisms, being involved in a large number of chemical reactions. Sequence variations in pantothenate kinase 2 (PANK2), the first enzyme of CoA biosynthesis, are found in patients affected by Pantothenate Kinase Associated Neurodegeneration (PKAN), one of the most common forms of neurodegeneration, with brain iron accumulation. Knowledge about the biochemical and molecular features of this disorder has increased a lot in recent years. Nonetheless, the main culprit of the pathology is not well defined, and no treatment option is available yet. In order to contribute to the understanding of this disease and facilitate the search for therapies, we explored the potential of the zebrafish animal model and generated lines carrying biallelic mutations in the pank2 gene. The phenotypic characterization of pank2-mutant embryos revealed anomalies in the development of venous vascular structures and germ cells. Adult fish showed testicular atrophy and altered behavioral response in an anxiety test but no evident signs of neurodegeneration. The study suggests that selected cell and tissue types show a higher vulnerability to pank2 deficiency in zebrafish. Deciphering the biological basis of this phenomenon could provide relevant clues for better understanding and treating PKAN.
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11
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Feng G, Sun Y. The Polycomb group gene rnf2 is essential for central and enteric neural system development in zebrafish. Front Neurosci 2022; 16:960149. [PMID: 36117635 PMCID: PMC9475114 DOI: 10.3389/fnins.2022.960149] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Accepted: 08/03/2022] [Indexed: 11/13/2022] Open
Abstract
The development of central nervous system (CNS) and enteric nervous system (ENS) is under precise and strict control in vertebrates. Whether and how the Polycomb repressive complex 1 (PRC1) is involved in it remain unclear. To investigate the role of PRC1 in the nervous system development, using CRISPR/Cas9 technology, we have generated mutant zebrafish lines for the rnf2 gene which encodes Ring1b, the enzymatic component of the PRC1 complex. We show that rnf2 loss of function leads to abnormal migration and differentiation of neural crest and neural precursor cells. rnf2 mutant embryos exhibit aganglionosis, in which the hindgut is devoid of neurons. In particular, the formation of 5-HT serotonin neurons and myelinating glial cells is defective. Furthermore, ectopic expression of ENS marker genes is observed in forebrain of rnf2 mutant embryos. These findings suggest that the rnf2 gene plays an important role in the migration and differentiation of neural precursor cells, and its absence leads to abnormal development of ENS and CNS in zebrafish.
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Affiliation(s)
- Gang Feng
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
- *Correspondence: Gang Feng,
| | - Yuhua Sun
- Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, China
- College of Advanced Agricultural Sciences, University of Chinese Academy of Sciences, Beijing, China
- Yuhua Sun,
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12
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Yuikawa T, Ikeda M, Tsuda S, Saito S, Yamasu K. Involvement of Oct4-type transcription factor Pou5f3 in posterior spinal cord formation in zebrafish embryos. Dev Growth Differ 2021; 63:306-322. [PMID: 34331767 DOI: 10.1111/dgd.12742] [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: 05/30/2021] [Revised: 07/13/2021] [Accepted: 07/27/2021] [Indexed: 12/21/2022]
Abstract
In vertebrate embryogenesis, elongation of the posterior body is driven by de novo production of the axial and paraxial mesoderm as well as the neural tube at the posterior end. This process is presumed to depend on the stem cell-like population in the tail bud region, but the details of the gene regulatory network involved are unknown. Previous studies suggested the involvement of pou5f3, an Oct4-type POU gene in zebrafish, in axial elongation. In the present study, we first found that pou5f3 is expressed mainly in the dorsal region of the tail bud immediately after gastrulation, and that this expression is restricted to the posterior-most region of the elongating neural tube during somitogenesis. This pou5f3 expression was complementary to the broad expression of sox3 in the neural tube, and formed a sharp boundary with specific expression of tbxta (orthologue of mammalian T/Brachyury) in the tail bud, implicating pou5f3 in the specification of tail bud-derived cells toward neural differentiation in the spinal cord. When pou5f3 was functionally impaired after gastrulation by induction of a dominant-interfering pou5f3 mutant gene (en-pou5f3), trunk and tail elongation were markedly disturbed at distinct positions along the axis depending on the stage. This finding showed involvement of pou5f3 in de novo generation of the body from the tail bud. Conditional functional abrogation also showed that pou5f3 downregulates mesoderm-forming genes but promotes neural development by activating neurogenesis genes around the tail bud. These results suggest that pou5f3 is involved in formation of the posterior spinal cord.
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Affiliation(s)
- Tatsuya Yuikawa
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Japan
| | - Masaaki Ikeda
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Japan
| | - Sachiko Tsuda
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Japan
| | - Shinji Saito
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Japan
| | - Kyo Yamasu
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Saitama City, Japan
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13
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Korzh S, Winata CL, Gong Z, Korzh V. The development of zebrafish pancreas affected by deficiency of Hedgehog signaling. Gene Expr Patterns 2021; 41:119185. [PMID: 34087472 DOI: 10.1016/j.gep.2021.119185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 03/29/2021] [Accepted: 05/07/2021] [Indexed: 10/21/2022]
Abstract
The pancreas development depends on complex regulation of several signaling pathways, including the Hedgehog (Hh) signaling via a receptor complex component, Smoothened, which deficiency blocks the Hh signaling. Such a defect in birds and mammals results in an annular pancreas. We showed that in developing zebrafish, the mutation of Smoothened or inhibition of Hh signaling by its antagonist cyclopamine caused developmental defects of internal organs, liver, pancreas, and gut. In particular, the pancreatic primordium was duplicated. The two exocrine pancreatic primordia surround the gut. This phenomenon correlates with a significant reduction of the gut's diameter, causing the annular pancreas phenotype.
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Affiliation(s)
- Svitlana Korzh
- -Department of Biological Sciences, National University of Singapore, Singapore
| | - Cecilia L Winata
- -International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Zhiyuan Gong
- -Department of Biological Sciences, National University of Singapore, Singapore.
| | - Vladimir Korzh
- -International Institute of Molecular and Cell Biology in Warsaw, Poland; -Institute of Molecular and Cell Biology, Singapore.
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14
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Fontenas L, Kucenas S. Spinal cord precursors utilize neural crest cell mechanisms to generate hybrid peripheral myelinating glia. eLife 2021; 10:64267. [PMID: 33554855 PMCID: PMC7886336 DOI: 10.7554/elife.64267] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 02/05/2021] [Indexed: 12/11/2022] Open
Abstract
During development, oligodendrocytes and Schwann cells myelinate central and peripheral nervous system axons, respectively, while motor exit point (MEP) glia are neural tube-derived, peripheral glia that myelinate axonal territory between these populations at MEP transition zones. From which specific neural tube precursors MEP glia are specified, and how they exit the neural tube to migrate onto peripheral motor axons, remain largely unknown. Here, using zebrafish, we found that MEP glia arise from lateral floor plate precursors and require foxd3 to delaminate and exit the spinal cord. Additionally, we show that similar to Schwann cells, MEP glial development depends on axonally derived neuregulin1. Finally, our data demonstrate that overexpressing axonal cues is sufficient to generate additional MEP glia in the spinal cord. Overall, these studies provide new insight into how a novel population of hybrid, peripheral myelinating glia are generated from neural tube precursors and migrate into the periphery.
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Affiliation(s)
- Laura Fontenas
- Department of Biology, University of Virginia, Charlottesville, United States
| | - Sarah Kucenas
- Department of Biology, University of Virginia, Charlottesville, United States
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15
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Yang S, Emelyanov A, You MS, Sin M, Korzh V. Camel regulates development of the brain ventricular system. Cell Tissue Res 2021; 383:835-852. [PMID: 32902807 PMCID: PMC7904751 DOI: 10.1007/s00441-020-03270-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2020] [Accepted: 07/29/2020] [Indexed: 10/25/2022]
Abstract
Development of the brain ventricular system of vertebrates and the molecular mechanisms involved are not fully understood. The developmental genes expressed in the elements of the brain ventricular system such as the ependyma and circumventricular organs act as molecular determinants of cell adhesion critical for the formation of brain ventricular system. They control brain development and function, including the flow of cerebrospinal fluid. Here, we describe the novel distantly related member of the zebrafish L1-CAM family of genes-camel. Whereas its maternal transcripts distributed uniformly, the zygotic transcripts demonstrate clearly defined expression patterns, in particular in the axial structures: floor plate, hypochord, and roof plate. camel expresses in several other cell lineages with access to the brain ventricular system, including the midbrain roof plate, subcommissural organ, organum vasculosum lamina terminalis, median eminence, paraventricular organ, flexural organ, and inter-rhombomeric boundaries. This expression pattern suggests a role of Camel in neural development. Several isoforms of Camel generated by differential splicing of exons encoding the sixth fibronectin type III domain enhance cell adhesion differentially. The antisense oligomer morpholino-mediated loss-of-function of Camel affects cell adhesion and causes hydrocephalus and scoliosis manifested via the tail curled down phenotype. The subcommissural organ's derivative-the Reissner fiber-participates in the flow of cerebrospinal fluid. The Reissner fiber fails to form upon morpholino-mediated Camel loss-of-function. The Camel mRNA-mediated gain-of-function causes the Reissner fiber misdirection. This study revealed a link between Chl1a/Camel and Reissner fiber formation, and this supports the idea that CHL1 is one of the scoliosis factors.
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Affiliation(s)
- Shulan Yang
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
- Translational Medicine Centre, The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China
| | - Alexander Emelyanov
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
- Institute for Research on Cancer and Aging, Nice, France
| | - May-Su You
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
- National Health Research Institutes, Zhunan, Taiwan
| | - Melvin Sin
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
| | - Vladimir Korzh
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.
- International Institute of Molecular and Cell Biology, Warsaw, Poland.
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16
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Mignani L, Zizioli D, Borsani G, Monti E, Finazzi D. The Downregulation of c19orf12 Negatively Affects Neuronal and Musculature Development in Zebrafish Embryos. Front Cell Dev Biol 2021; 8:596069. [PMID: 33425903 PMCID: PMC7785858 DOI: 10.3389/fcell.2020.596069] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/30/2020] [Indexed: 11/13/2022] Open
Abstract
Mitochondrial membrane Protein Associated Neurodegeneration (MPAN) is a rare genetic disorder due to mutations in C19orf12 gene. In most cases, the disorder is transmitted as an autosomal recessive trait and the main clinical features are progressive spastic para/tetraparesis, dystonia, motor axonal neuropathy, parkinsonisms, psychiatric symptoms, and optic atrophy. Besides iron accumulation in the globus pallidus and substantia nigra, the neuropathology shows features also observed in Parkinson’s Disease brains, such as α-synuclein-positive Lewy bodies and hyperphosphorylated tau. Mutations in the gene have been found in other neurodegenerative disorders, including PD, hereditary spastic paraplegia, pallido-pyramidal syndrome, and amyotrophic lateral sclerosis. The biological function of C19orf12 gene is poorly defined. In humans, it codes for two protein isoforms: the longer one is present in mitochondria, endoplasmic reticulum, and contact regions between mitochondria and ER. Mutations in the gene appear to be linked to defects in mitochondrial activity, lipid metabolism and autophagy/mitophagy. To increase the available tools for the investigation of MPAN pathogenesis, we generated a new animal model in zebrafish embryos. The zebrafish genome contains four co-orthologs of human C19orf12. One of them, located on chromosome 18, is expressed at higher levels at early stages of development. We downregulated its expression by microinjecting embryos with a specific ATG-blocking morpholino, and we analyzed embryonal development. Most embryos showed morphological defects such as unsettled brain morphology, with smaller head and eyes, reduced yolk extension, tilted and thinner tail. The severity of the defects progressively increased and all injected embryos died within 7 days post fertilization. Appropriate controls confirmed the specificity of the observed phenotype. Changes in the expression and distribution of neural markers documented a defective neuronal development, particularly evident in the eyes, the optic tectum, the midbrain-hindbrain boundary; Rohon Beard and dorsal root ganglia neurons were also affected. Phalloidin staining evidenced a significant perturbation of musculature formation that was associated with defective locomotor behavior. These data are consistent with the clinical features of MPAN and support the validity of the model to investigate the pathogenesis of the disease and evaluate molecules with potential therapeutic effect.
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Affiliation(s)
- Luca Mignani
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Daniela Zizioli
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Giuseppe Borsani
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Eugenio Monti
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy
| | - Dario Finazzi
- Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy.,Laboratory of Clinical Chemistry, Azienda Socio Sanitaria Territoriale (ASST) Spedali Civili di Brescia, Brescia, Italy
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17
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Raj B, Farrell JA, Liu J, El Kholtei J, Carte AN, Navajas Acedo J, Du LY, McKenna A, Relić Đ, Leslie JM, Schier AF. Emergence of Neuronal Diversity during Vertebrate Brain Development. Neuron 2020; 108:1058-1074.e6. [PMID: 33068532 PMCID: PMC8286448 DOI: 10.1016/j.neuron.2020.09.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Revised: 08/05/2020] [Accepted: 09/17/2020] [Indexed: 01/03/2023]
Abstract
Neurogenesis comprises many highly regulated processes including proliferation, differentiation, and maturation. However, the transcriptional landscapes underlying brain development are poorly characterized. We describe a developmental single-cell catalog of ∼220,000 zebrafish brain cells encompassing 12 stages from embryo to larva. We characterize known and novel gene markers for ∼800 clusters and provide an overview of the diversification of neurons and progenitors across these time points. We also introduce an optimized GESTALT lineage recorder that enables higher expression and recovery of Cas9-edited barcodes to query lineage segregation. Cell type characterization indicates that most embryonic neural progenitor states are transitory and transcriptionally distinct from neural progenitors of post-embryonic stages. Reconstruction of cell specification trajectories reveals that late-stage retinal neural progenitors transcriptionally overlap cell states observed in the embryo. The zebrafish brain development atlas provides a resource to define and manipulate specific subsets of neurons and to uncover the molecular mechanisms underlying vertebrate neurogenesis.
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Affiliation(s)
- Bushra Raj
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA.
| | - Jeffrey A Farrell
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Unit on Cell Specification and Differentiation, National Institute of Child Health and Human Development, NIH, Bethesda, MD 20814, USA
| | - Jialin Liu
- Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Jakob El Kholtei
- Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Adam N Carte
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland; Systems, Synthetic, and Quantitative Biology Program, Harvard University, Cambridge, MA 02138, USA
| | - Joaquin Navajas Acedo
- Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Lucia Y Du
- Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland
| | - Aaron McKenna
- Department of Molecular and Systems Biology, Dartmouth Geisel School of Medicine, Lebanon, NH 03756, USA
| | - Đorđe Relić
- Biozentrum, University of Basel, 4056 Basel, Switzerland; Swiss Institute of Bioinformatics (SIB), 4056 Basel, Switzerland
| | - Jessica M Leslie
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA
| | - Alexander F Schier
- Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Allen Discovery Center for Cell Lineage Tracing, Seattle, WA, USA; Biozentrum, University of Basel, 4056 Basel, Switzerland; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA; Harvard Stem Cell Institute, Harvard University, Cambridge, MA 02138, USA; Center for Brain Science, Harvard University, Cambridge, MA 02138, USA.
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18
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Jedrychowska J, Gasanov EV, Korzh V. Kcnb1 plays a role in development of the inner ear. Dev Biol 2020; 471:65-75. [PMID: 33316259 DOI: 10.1016/j.ydbio.2020.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Revised: 12/03/2020] [Accepted: 12/07/2020] [Indexed: 10/22/2022]
Abstract
The function of the inner ear depends on the maintenance of high concentrations of K+ ions. The slow-inactivating delayed rectifier Kv2.1/KCNB1 channel works in the inner ear in mammals. The kcnb1 gene is expressed in the otic vesicle of developing zebrafish, suggesting its role in development of the inner ear. In the present study, we found that a Kcnb1 loss-of-function mutation affected development of the inner ear at multiple levels, including otic vesicle expansion, otolith formation, and the proliferation and differentiation of mechanosensory cells. This resulted in defects of kinocilia and stereocilia and abnormal function of the inner ear detected by behavioral assays. The quantitative transcriptional analysis of 75 genes demonstrated that the kcnb1 mutation affected the transcription of genes that are involved in K+ metabolism, cell proliferation, cilia development, and intracellular protein trafficking. These results demonstrate a role for Kv2.1/Kcnb1 channels in development of the inner ear in zebrafish.
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Affiliation(s)
- Justyna Jedrychowska
- International Institute of Molecular and Cell Biology in Warsaw, Poland; Postgraduate School of Molecular Medicine, Warsaw Medical University, Warsaw, Poland
| | - Eugene V Gasanov
- International Institute of Molecular and Cell Biology in Warsaw, Poland
| | - Vladimir Korzh
- International Institute of Molecular and Cell Biology in Warsaw, Poland.
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19
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Kantarci H, Gou Y, Riley BB. The Warburg Effect and lactate signaling augment Fgf-MAPK to promote sensory-neural development in the otic vesicle. eLife 2020; 9:56301. [PMID: 32338604 PMCID: PMC7253172 DOI: 10.7554/elife.56301] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2020] [Accepted: 04/26/2020] [Indexed: 12/26/2022] Open
Abstract
Recent studies indicate that many developing tissues modify glycolysis to favor lactate synthesis (Agathocleous et al., 2012; Bulusu et al., 2017; Gu et al., 2016; Oginuma et al., 2017; Sá et al., 2017; Wang et al., 2014; Zheng et al., 2016), but how this promotes development is unclear. Using forward and reverse genetics in zebrafish, we show that disrupting the glycolytic gene phosphoglycerate kinase-1 (pgk1) impairs Fgf-dependent development of hair cells and neurons in the otic vesicle and other neurons in the CNS/PNS. Fgf-MAPK signaling underperforms in pgk1- / - mutants even when Fgf is transiently overexpressed. Wild-type embryos treated with drugs that block synthesis or secretion of lactate mimic the pgk1- / - phenotype, whereas pgk1- / - mutants are rescued by treatment with exogenous lactate. Lactate treatment of wild-type embryos elevates expression of Etv5b/Erm even when Fgf signaling is blocked. However, lactate’s ability to stimulate neurogenesis is reversed by blocking MAPK. Thus, lactate raises basal levels of MAPK and Etv5b (a critical effector of the Fgf pathway), rendering cells more responsive to dynamic changes in Fgf signaling required by many developing tissues.
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Affiliation(s)
- Husniye Kantarci
- Biology Department, Texas A&M University, College Station, United States
| | - Yunzi Gou
- Biology Department, Texas A&M University, College Station, United States
| | - Bruce B Riley
- Biology Department, Texas A&M University, College Station, United States
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20
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Coolen M, Labusch M, Mannioui A, Bally-Cuif L. Mosaic Heterochrony in Neural Progenitors Sustains Accelerated Brain Growth and Neurogenesis in the Juvenile Killifish N. furzeri. Curr Biol 2020; 30:736-745.e4. [PMID: 32004451 PMCID: PMC7040570 DOI: 10.1016/j.cub.2019.12.046] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Revised: 11/16/2019] [Accepted: 12/13/2019] [Indexed: 12/19/2022]
Abstract
Although developmental mechanisms driving an increase in brain size during vertebrate evolution are actively studied, we know less about evolutionary strategies allowing accelerated brain growth. In zebrafish and other vertebrates studied to date, apical radial glia (RG) constitute the primary neurogenic progenitor population throughout life [1]; thus, RG activity is a determining factor of growth speed. Here, we ask whether enhanced RG activity is the mechanism selected to drive explosive growth, in adaptation to an ephemeral habitat. In post-hatching larvae of the turquoise killifish, which display drastic developmental acceleration, we show that the dorsal telencephalon (pallium) grows three times faster than in zebrafish. Rather than resulting from enhanced RG activity, we demonstrate that pallial growth is the product of a second type of progenitors (that we term NGPs for non-glial progenitors) that actively sustains neurogenesis and germinal zone self-renewal. Intriguingly, NGPs appear to retain, at larval stages, features of early embryonic progenitors. In parallel, RGs enter premature quiescence and express markers of astroglial function. Altogether, we propose that mosaic heterochrony within the neural progenitor population might permit rapid pallial growth by safeguarding both continued neurogenesis and astroglial function. Two types of apical progenitors exist in the pallium of the fast-growing killifish Killifish pallial RGs enter precociously into an adult-like quiescent state NGPs, both self-renewing and neurogenic, resemble early neuroepithelial progenitors Mosaic heterochrony among progenitors sustains rapid killifish pallial growth
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Affiliation(s)
- Marion Coolen
- Zebrafish Neurogenetics Unit, Developmental & Stem Cell Biology Department, Institut Pasteur, UMR3738, CNRS, 25 rue du Dr Roux, 75015 Paris, France.
| | - Miriam Labusch
- Zebrafish Neurogenetics Unit, Developmental & Stem Cell Biology Department, Institut Pasteur, UMR3738, CNRS, 25 rue du Dr Roux, 75015 Paris, France; Sorbonne Université, Collège doctoral, 75005 Paris, France
| | - Abdelkrim Mannioui
- Institut de Biologie Paris-Seine (IBPS), Aquatic Facility, Sorbonne Université, 7 quai Saint Bernard, 75005 Paris, France
| | - Laure Bally-Cuif
- Zebrafish Neurogenetics Unit, Developmental & Stem Cell Biology Department, Institut Pasteur, UMR3738, CNRS, 25 rue du Dr Roux, 75015 Paris, France.
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21
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Inomata C, Yuikawa T, Nakayama-Sadakiyo Y, Kobayashi K, Ikeda M, Chiba M, Konishi C, Ishioka A, Tsuda S, Yamasu K. Involvement of an Oct4-related PouV gene, pou5f3/pou2, in neurogenesis in the early neural plate of zebrafish embryos. Dev Biol 2020; 457:30-42. [DOI: 10.1016/j.ydbio.2019.09.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 09/09/2019] [Accepted: 09/10/2019] [Indexed: 01/03/2023]
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22
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Cook ZT, Brockway NL, Tobias ZJC, Pajarla J, Boardman IS, Ippolito H, Nkombo Nkoula S, Weissman TA. Combining near-infrared fluorescence with Brainbow to visualize expression of specific genes within a multicolor context. Mol Biol Cell 2019; 30:491-505. [PMID: 30586321 PMCID: PMC6594444 DOI: 10.1091/mbc.e18-06-0340] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 12/13/2018] [Accepted: 12/18/2018] [Indexed: 12/18/2022] Open
Abstract
Fluorescent proteins are a powerful experimental tool, allowing the visualization of gene expression and cellular behaviors in a variety of systems. Multicolor combinations of fluorescent proteins, such as Brainbow, have expanded the range of possible research questions and are useful for distinguishing and tracking cells. The addition of a separately driven color, however, would allow researchers to report expression of a manipulated gene within the multicolor context to investigate mechanistic effects. A far-red or near-infrared protein could be particularly suitable in this context, as these can be distinguished spectrally from Brainbow. We investigated five far-red/near-infrared proteins in zebrafish: TagRFP657, mCardinal, miRFP670, iRFP670, and mIFP. Our results show that both mCardinal and iRFP670 are useful fluorescent proteins for zebrafish expression. We also introduce a new transgenic zebrafish line that expresses Brainbow under the control of the neuroD promoter. We demonstrate that mCardinal can be used to track the expression of a manipulated bone morphogenetic protein receptor within the Brainbow context. The overlay of near-infrared fluorescence onto a Brainbow background defines a clear strategy for future research questions that aim to manipulate or track the effects of specific genes within a population of cells that are delineated using multicolor approaches.
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Affiliation(s)
- Zoe T. Cook
- Biology Department, Lewis and Clark College, Portland, OR 97219
| | | | | | - Joy Pajarla
- Biology Department, Lewis and Clark College, Portland, OR 97219
| | | | - Helen Ippolito
- Biology Department, Lewis and Clark College, Portland, OR 97219
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23
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Hsieh YC, Chiang MC, Huang YC, Yeh TH, Shih HY, Liu HF, Chen HY, Wang CP, Cheng YC. Pparα deficiency inhibits the proliferation of neuronal and glial precursors in the zebrafish central nervous system. Dev Dyn 2018; 247:1264-1275. [DOI: 10.1002/dvdy.24683] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 09/12/2018] [Accepted: 10/16/2018] [Indexed: 12/28/2022] Open
Affiliation(s)
- Yen-Che Hsieh
- Graduate Institute of Biomedical Sciences, College of Medicine; Chang Gung University; Taoyuan Taiwan
| | - Ming-Chang Chiang
- Department of Life Science; Fu Jen Catholic University; New Taipei City Taiwan
| | - Yin-Cheng Huang
- College of Medicine; Chang Gung University; Taoyuan Taiwan
- Department of Neurosurgery; Chang Gung Memorial Hospital; Linkou, Taoyuan Taiwan
| | - Tu-Hsueh Yeh
- College of Medicine; Chang Gung University; Taoyuan Taiwan
- Neuroscience Research Center, Chang Gung Memorial Hospital; Linkou, Taoyuan Taiwan
- Section of Movement Disorders, Department of Neurology; Chang Gung Memorial Hospital; Linkou, Taoyuan Taiwan
- Department of Neurology; Taipei Medical University Hospital; Taipei Taiwan
| | - Hung-Yu Shih
- Graduate Institute of Biomedical Sciences, College of Medicine; Chang Gung University; Taoyuan Taiwan
| | - Han-Fang Liu
- Graduate Institute of Biomedical Sciences, College of Medicine; Chang Gung University; Taoyuan Taiwan
| | - Hao-Yuan Chen
- Graduate Institute of Biomedical Sciences, College of Medicine; Chang Gung University; Taoyuan Taiwan
| | - Chien-Ping Wang
- School of Medicine, College of Medicine, Chang Gung University; Taoyuan Taiwan
| | - Yi-Chuan Cheng
- Graduate Institute of Biomedical Sciences, College of Medicine; Chang Gung University; Taoyuan Taiwan
- College of Medicine; Chang Gung University; Taoyuan Taiwan
- Neuroscience Research Center, Chang Gung Memorial Hospital; Linkou, Taoyuan Taiwan
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Naderi M, Ferrari MCO, Chivers DP, Niyogi S. Maternal Exposure to Dietary Selenium Causes Dopaminergic Hyperfunction and Cognitive Impairment in Zebrafish Offspring. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13574-13583. [PMID: 30335985 DOI: 10.1021/acs.est.8b04768] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Maternal exposure to environmental contaminants is a predisposing factor for neurodevelopmental disorders with associated cognitive and social deficits in offspring. In this study, we investigated the effects of maternal exposure to selenium (Se), a contaminant of potential environmental concern in aquatic ecosystems, on cognitive performance and the underlying mechanisms in F1-generation adult zebrafish. Adult female zebrafish were exposed to different concentrations of dietary Se (3.5, 11.1, or 27.4 μg Se/g dry weight) for a period of 60 days. Fish were subsequently bred, and their offspring were collected and raised for 6 months on a normal diet. Maternal exposure to all concentrations of dietary Se induced learning impairment in F1-zebrafish tested in a latent learning task. The results also showed a hyperfunctioning dopaminergic system in fish exhibiting the learning deficit. The hyperfunction of the dopaminergic system was associated with enhanced oxidative stress and alterations in the mRNA abundance of several immediate early and late response genes in the zebrafish brain. Taken together, these results suggest that maternal exposure to dietary Se via alterations in the dopaminergic system leads to persistent neurobehavioral deficits in F1-generation adult zebrafish.
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Affiliation(s)
- Mohammad Naderi
- Department of Biology , University of Saskatchewan , 112 Science Place , Saskatoon , SK S7N 5E2 , Canada
| | - Maud C O Ferrari
- Department of Veterinary Biomedical Sciences , University of Saskatchewan , 52 Campus Drive , Saskatoon , SK S7N 5B4 , Canada
| | - Douglas P Chivers
- Department of Biology , University of Saskatchewan , 112 Science Place , Saskatoon , SK S7N 5E2 , Canada
| | - Som Niyogi
- Department of Biology , University of Saskatchewan , 112 Science Place , Saskatoon , SK S7N 5E2 , Canada
- Toxicology Centre , University of Saskatchewan , 44 Campus Drive , Saskatoon , SK S7N 5B3 , Canada
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25
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Lyons DD, Morrison C, Philibert DA, Gamal El-Din M, Tierney KB. Growth and recovery of zebrafish embryos after developmental exposure to raw and ozonated oil sands process-affected water. CHEMOSPHERE 2018; 206:405-413. [PMID: 29758497 DOI: 10.1016/j.chemosphere.2018.05.028] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/03/2018] [Accepted: 05/04/2018] [Indexed: 06/08/2023]
Abstract
Due to the increasing volume of oil sands process-affect water (OSPW) and its toxicity to aquatic organisms, it is important to fully understand its effects and study remediation processes that will enable its release to the environment. Ozone treatment is currently being considered as a tool to expedite remediation, as it is known to degrade toxic organic compounds present in OSPW. In this study, we aimed to measure the effects of OSPW exposure on the growth, development and recovery of zebrafish (Danio rerio) embryos. We also used ozone-treated OSPW to determine whether ozonation negated any effects of raw OSPW exposure. As biomarkers of exposure, we assessed the expression of genes involved in neurodevelopment (ngn1, neuroD), estrogenicity (vtg), oxidative stress (sod1), and biotransformation (cyp1a, cyp1b). Our study found that exposure to both raw and ozonated OSPW did not impair growth of zebrafish embryos, however, otoliths of exposed embryos were smaller than those of control embryos. The expression levels of both cyp1a and cyp1b were induced by raw OSPW exposure. However, after the exposure period, expression levels of these genes returned to control levels within two days of residence in clean water. We found no changes in the expression levels of ngn1, neuroD and vtg genes with exposure to treated or untreated OSPW. Overall, our study found that raw OSPW exposure did not have many negative effects on zebrafish embryos and embryos appeared to recover relatively quickly after exposure ended. Furthermore, ozone treatment decreased the induction of cyp1a and cyp1b.
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Affiliation(s)
- Danielle D Lyons
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada.
| | - Christie Morrison
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Danielle A Philibert
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Mohamed Gamal El-Din
- Civil and Environmental Engineering, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
| | - Keith B Tierney
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta T6G 2E9, Canada; School of Public Health, University of Alberta, Edmonton, Alberta T6G 2E9, Canada
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26
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Babu A, Kamaraj M, Basu M, Mukherjee D, Kapoor S, Ranjan S, Swamy MM, Kaypee S, Scaria V, Kundu TK, Sachidanandan C. Chemical and genetic rescue of an ep300 knockdown model for Rubinstein Taybi Syndrome in zebrafish. Biochim Biophys Acta Mol Basis Dis 2018; 1864:1203-1215. [PMID: 29409755 DOI: 10.1016/j.bbadis.2018.01.029] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Revised: 01/08/2018] [Accepted: 01/27/2018] [Indexed: 10/18/2022]
Abstract
EP300 is a member of the EP300/CBP family of lysine acetyltransferases (KATs) with multiple roles in development and physiology. Loss of EP300/CBP activity in humans causes a very rare congenital disorder called Rubinstein Taybi Syndrome (RSTS). The zebrafish genome has two co-orthologs of lysine acetyltransferase EP300 (KAT3B) in zebrafish viz. ep300a and ep300b. Chemical inhibition of Ep300 with C646, a competitive inhibitor and morpholino-based genetic knockdown of ep300a and ep300b cause defects in embryonic development reminiscent of the human RSTS syndrome. Remarkably, overexpression of Ep300a KAT domain results in near complete rescue of the jaw development defects, a characteristic feature of RSTS in human suggesting the dispensability of the protein-interaction and DNA-binding domains for at least some developmental roles of Ep300. We also perform a chemical screen and identify two inhibitors of deacetylases, CHIC35 and HDACi III, that can partially rescue the RSTS-like phenotypes. Thus, modeling rare human genetic disorders in zebrafish allows for functional understanding of the genes involved and can also yield small molecule candidates towards therapeutic goals.
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Affiliation(s)
- Aswini Babu
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Mageshi Kamaraj
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India
| | - Moumita Basu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru 560064, India
| | - Debanjan Mukherjee
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru 560064, India
| | - Shruti Kapoor
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Shashi Ranjan
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India
| | - Mahadeva M Swamy
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru 560064, India
| | - Stephanie Kaypee
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru 560064, India
| | - Vinod Scaria
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India
| | - Tapas K Kundu
- Transcription and Disease Laboratory, Molecular Biology and Genetics Unit, Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR), Bengaluru 560064, India.
| | - Chetana Sachidanandan
- CSIR-Institute of Genomics & Integrative Biology, South Campus, New Delhi 110025, India; Academy of Scientific and Innovative Research (AcSIR), New Delhi 110025, India.
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27
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García-Lecea M, Gasanov E, Jedrychowska J, Kondrychyn I, Teh C, You MS, Korzh V. Development of Circumventricular Organs in the Mirror of Zebrafish Enhancer-Trap Transgenics. Front Neuroanat 2017; 11:114. [PMID: 29375325 PMCID: PMC5770639 DOI: 10.3389/fnana.2017.00114] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 11/22/2017] [Indexed: 11/18/2022] Open
Abstract
The circumventricular organs (CVOs) are small structures lining the cavities of brain ventricular system. They are associated with the semitransparent regions of the blood-brain barrier (BBB). Hence it is thought that CVOs mediate biochemical signaling and cell exchange between the brain and systemic blood. Their classification is still controversial and development not fully understood largely due to an absence of tissue-specific molecular markers. In a search for molecular determinants of CVOs we studied the green fluorescent protein (GFP) expression pattern in several zebrafish enhancer trap transgenics including Gateways (ET33-E20) that has been instrumental in defining the development of choroid plexus. In Gateways the GFP is expressed in regions of the developing brain outside the choroid plexus, which remain to be characterized. The neuroanatomical and histological analysis suggested that some previously unassigned domains of GFP expression may correspond to at least six other CVOs–the organum vasculosum laminae terminalis (OVLT), subfornical organ (SFO), paraventricular organ (PVO), pineal (epiphysis), area postrema (AP) and median eminence (ME). Two other CVOs, parapineal and subcommissural organ (SCO) were detected in other enhancer-trap transgenics. Hence enhancer-trap transgenic lines could be instrumental for developmental studies of CVOs in zebrafish and understanding of the molecular mechanism of disease such a hydrocephalus in human. Their future analysis may shed light on general and specific molecular mechanisms that regulate development of CVOs.
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Affiliation(s)
- Marta García-Lecea
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,Department of Basic Biomedical Sciences, Universidad Europea de Madrid, Madrid, Spain
| | - Evgeny Gasanov
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
| | - Justyna Jedrychowska
- International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland.,Postgraduate School of Molecular Medicine, Medical University of Warsaw, Warsaw, Poland
| | - Igor Kondrychyn
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,RIKEN Center for Developmental Biology, Kobe, Japan
| | - Cathleen Teh
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore
| | - May-Su You
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,National Health Research Institutes (NHRI), Zhunan, Taiwan
| | - Vladimir Korzh
- Institute of Molecular and Cell Biology, Agency for Science, Technology and Research, Singapore, Singapore.,International Institute of Molecular and Cell Biology in Warsaw, Warsaw, Poland
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28
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Xia L, Zheng L, Zhou JL. Effects of ibuprofen, diclofenac and paracetamol on hatch and motor behavior in developing zebrafish (Danio rerio). CHEMOSPHERE 2017; 182:416-425. [PMID: 28511137 DOI: 10.1016/j.chemosphere.2017.05.054] [Citation(s) in RCA: 107] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 05/05/2017] [Accepted: 05/09/2017] [Indexed: 06/07/2023]
Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) which are widely used as pain relief medicines are causing increasing environmental concern due to their incomplete removal in wastewater treatment plant and potential toxicity on endocrine, kidney and reproduction in teleost fish. This study focused on the effects of widely used ibuprofen, diclofenac and paracetamol on the hatch and motor ability of early-stage zebrafish, by exposing embryos to the target chemicals at 5, 50 and 500 μg/L starting from 6 h postfertilization (hpf). A significant reduction in hatch rate at 55 hpf was caused by both ibuprofen (-63%) and diclofenac (-58%) at 500 μg/L. Exposure to high concentration of ibuprofen significantly decreased the spontaneous movement by 25%, and reduced the free swimming distance, duration and speed under dark condition by 41%, 29% and 30%, respectively. High concentration of diclofenac also caused 23% decrease in spontaneous movement, and reduced the swimming distance as well as active duration by 17% and 13% under light stimulation. In comparison, the exposure to paracetamol did not cause any notable effect. Among neuron related genes tested, the expression of neurog1 was down-regulated from ibuprofen and diclofenac exposure by 19% and 26%, while the expression of neurod1 was up-regulated only by ibuprofen (31%). These findings indicated that ibuprofen and diclofenac significantly affected embryo locomotivity and were potentially neurotoxic, thus posing threats to zebrafish development.
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Affiliation(s)
- Liang Xia
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhangshan Road, Shanghai, 200062, China
| | - Liang Zheng
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhangshan Road, Shanghai, 200062, China
| | - Jun Liang Zhou
- State Key Laboratory of Estuarine and Coastal Research, East China Normal University, 3663 North Zhangshan Road, Shanghai, 200062, China.
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29
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Brorin is required for neurogenesis, gliogenesis, and commissural axon guidance in the zebrafish forebrain. PLoS One 2017; 12:e0176036. [PMID: 28448525 PMCID: PMC5407822 DOI: 10.1371/journal.pone.0176036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2016] [Accepted: 04/04/2017] [Indexed: 12/28/2022] Open
Abstract
Bmps regulate numerous neural functions with their regulators. We previously identified Brorin, a neural-specific secreted antagonist of Bmp signaling, in humans, mice, and zebrafish. Mouse Brorin has two cysteine-rich domains containing 10 cysteine residues in its core region, and these are located in similar positions to those in the cysteine-rich domains of Chordin family members, which are secreted Bmp antagonists. Zebrafish Brorin had two cysteine-rich domains with high similarity to those of mouse Brorin. We herein examined zebrafish brorin in order to elucidate its in vivo actions. Zebrafish brorin was predominantly expressed in developing neural tissues. The overexpression of brorin led to the inactivation of Bmp signaling. On the other hand, the knockdown of brorin resulted in the activation of Bmp signaling and brorin morphants exhibited defective development of the ventral domain in the forebrain. Furthermore, the knockdown of brorin inhibited the generation of γ–aminobutyric acid (GABA)ergic interneurons and oligodendrocytes and promoted the generation of astrocytes in the forebrain. In addition, brorin was required for axon guidance in the forebrain. The present results suggest that Brorin is a secreted Bmp antagonist predominantly expressed in developing neural tissues and that it plays multiple roles in the development of the zebrafish forebrain.
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30
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γ2 and γ1AP-1 complexes: Different essential functions and regulatory mechanisms in clathrin-dependent protein sorting. Eur J Cell Biol 2017; 96:356-368. [PMID: 28372831 DOI: 10.1016/j.ejcb.2017.03.008] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 03/24/2017] [Accepted: 03/24/2017] [Indexed: 11/20/2022] Open
Abstract
γ2 adaptin is homologous to γ1, but is only expressed in vertebrates while γ1 is found in all eukaryotes. We know little about γ2 functions and their relation to γ1. γ1 is an adaptin of the heterotetrameric AP-1 complexes, which sort proteins in and do form clathrin-coated transport vesicles and they also regulate maturation of early endosomes. γ1 knockout mice develop only to blastocysts and thus γ2 does not compensate γ1-deficiency in development. γ2 has not been classified as a clathrin-coated vesicle adaptor protein in proteome analyses and functions for monomeric γ2 in endosomal protein sorting have been proposed, but adaptin interaction studies suggested formation of heterotetrameric AP-1/γ2 complexes. We detected γ2 at the trans-Golgi network, on peripheral vesicles and identified γ2 clathrin-coated vesicles in mice. Ubiquitous σ1A and tissue-specific σ1B adaptins bind γ2 and γ1. σ1B knockout in mice does not effect γ1/σ1A AP-1 levels, but γ2/σ1A AP-1 levels are increased in brain and adipocytes. Also γ2 is essential in development. In zebrafish AP-1/γ2 and AP-1/γ1 fulfill different, essential functions in brain and the vascular system.
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31
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Abstract
The zebrafish pancreas shares its basic organization and cell types with the mammalian pancreas. In addition, the developmental pathways that lead to the establishment of the pancreatic islets of Langherhans are generally conserved from fish to mammals. Zebrafish provides a powerful tool to probe the mechanisms controlling establishment of the pancreatic endocrine cell types from early embryonic progenitor cells, as well as the regeneration of endocrine cells after damage. This knowledge is, in turn, applicable to refining protocols to generate renewable sources of human pancreatic islet cells that are critical for regulation of blood sugar levels. Here, we review how previous and ongoing studies in zebrafish and beyond are influencing the understanding of molecular mechanisms underlying various forms of diabetes and efforts to develop cell-based approaches to cure this increasingly widespread disease.
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32
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Down-regulation of coasy, the gene associated with NBIA-VI, reduces Bmp signaling, perturbs dorso-ventral patterning and alters neuronal development in zebrafish. Sci Rep 2016; 6:37660. [PMID: 27892483 PMCID: PMC5124858 DOI: 10.1038/srep37660] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Accepted: 11/01/2016] [Indexed: 12/16/2022] Open
Abstract
Mutations in Pantothenate kinase 2 and Coenzyme A (CoA) synthase (COASY), genes involved in CoA biosynthesis, are associated with rare neurodegenerative disorders with brain iron accumulation. We showed that zebrafish pank2 gene plays an essential role in brain and vasculature development. Now we extended our study to coasy. The gene has high level of sequence identity with the human ortholog and is ubiquitously expressed from the earliest stages of development. The abrogation of its expression led to strong reduction of CoA content, high lethality and a phenotype resembling to that of dorsalized mutants. Lower doses of morpholino resulted in a milder phenotype, with evident perturbation in neurogenesis and formation of vascular arborization; the dorso-ventral patterning was severely affected, the expression of bone morphogenetic protein (Bmp) receptors and activity were decreased, while cell death increased. These features specifically correlated with the block in CoA biosynthesis and were rescued by the addition of CoA to fish water and the overexpression of the human wild-type, but not mutant gene. These results confirm the absolute requirement for adequate levels of CoA for proper neural and vascular development in zebrafish and point to the Bmp pathway as a possible molecular connection underlining the observed phenotype.
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33
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Development of the cardiac conduction system in zebrafish. Gene Expr Patterns 2016; 21:89-96. [PMID: 27593944 DOI: 10.1016/j.gep.2016.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2016] [Revised: 08/24/2016] [Accepted: 08/28/2016] [Indexed: 01/29/2023]
Abstract
The cardiac conduction system (CCS) propagates and coordinates the electrical excitation that originates from the pacemaker cells, throughout the heart, resulting in rhythmic heartbeat. Its defects result in life-threatening arrhythmias and sudden cardiac death. Understanding of the factors involved in the formation and function of the CCS remains incomplete. By transposon assisted transgenesis, we have developed enhancer trap (ET) lines of zebrafish that express fluorescent protein in the pacemaker cells at the sino-atrial node (SAN) and the atrio-ventricular region (AVR), termed CCS transgenics. This expression pattern begins at the stage when the heart undergoes looping morphogenesis at 36 h post fertilization (hpf) and is maintained into adulthood. Using the CCS transgenics, we investigated the effects of perturbation of cardiac function, as simulated by either the absence of endothelium or hemodynamic stimulation, on the cardiac conduction cells, which resulted in abnormal compaction of the SAN. To uncover the identity of the gene represented by the EGFP expression in the CCS transgenics, we mapped the transposon integration sites on the zebrafish genome to positions in close proximity to the gene encoding fibroblast growth homologous factor 2a (fhf2a). Fhf2a is represented by three transcripts, one of which is expressed in the developing heart. These transgenics are useful tools for studies of development of the CCS and cardiac disease.
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Guarienti M, Cardozo SM, Borgese L, Lira GR, Depero LE, Bontempi E, Presta M. COSMOS-rice technology abrogates the biotoxic effects of municipal solid waste incinerator residues. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 214:713-721. [PMID: 27149148 DOI: 10.1016/j.envpol.2016.04.053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/11/2016] [Accepted: 04/15/2016] [Indexed: 06/05/2023]
Abstract
Fly ashes generated by municipal solid waste incinerator (MSWI) are classified as hazardous waste and usually landfilled. For the sustainable reuse of these materials is necessary to reduce the resulting impact on human health and environment. The COSMOS-rice technology has been recently proposed for the treatment of fly ashes mixed with rice husk ash, to obtain a low-cost composite material with significant performances. Here, aquatic biotoxicity assays, including daphnidae and zebrafish embryo-based tests, were used to assess the biosafety efficacy of this technology. Exposure to lixiviated MSWI fly ash caused dose-dependent biotoxic effects on daphnidae and zebrafish embryos with alterations of embryonic development, teratogenous defects and apoptotic events. On the contrary, no biotoxic effects were observed in daphnidae and zebrafish embryos exposed to lixiviated COSMOS-rice material. Accordingly, whole-mount in situ hybridization analysis of the expression of various tissue-specific genes in zebrafish embryos provided genetic evidence about the ability of COSMOS-rice stabilization process to minimize the biotoxic effects of MSWI fly ash. These results demonstrate at the biological level that the newly developed COSMOS-rice technology is an efficient and cost-effective method to process MSWI fly ash, producing a biologically safe and reusable material.
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Affiliation(s)
- Michela Guarienti
- Zebrafish Facility, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Sdenka Moscoso Cardozo
- Zebrafish Facility, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy
| | - Laura Borgese
- INSTM and Chemistry for Technologies Laboratory, University of Brescia, Via Branze, 38, 25123 Brescia, Italy
| | - Gloria Rodrigo Lira
- Unidad de Vigilancia Ambiental y Genotoxicologia, Instituto de Biologia Molecular y Biotecnologia, Universidad Mayor de San Andres, La Paz, Bolivia
| | - Laura E Depero
- INSTM and Chemistry for Technologies Laboratory, University of Brescia, Via Branze, 38, 25123 Brescia, Italy
| | - Elza Bontempi
- INSTM and Chemistry for Technologies Laboratory, University of Brescia, Via Branze, 38, 25123 Brescia, Italy
| | - Marco Presta
- Zebrafish Facility, Department of Molecular and Translational Medicine, University of Brescia, Viale Europa 11, 25123 Brescia, Italy.
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β-Amyloid precursor protein-b is essential for Mauthner cell development in the zebrafish in a Notch-dependent manner. Dev Biol 2016; 413:26-38. [PMID: 26994945 DOI: 10.1016/j.ydbio.2016.03.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Accepted: 03/10/2016] [Indexed: 02/05/2023]
Abstract
Amyloid precursor protein (APP) is a transmembrane glycoprotein that has been the subject of intense research because of its implication in Alzheimer's disease. However, the physiological function of APP in the development and maintenance of the central nervous system remains largely unknown. We have previously shown that the APP homologue in zebrafish (Danio rerio), Appb, is required for motor neuron patterning and formation. Here we study the function of Appb during neurogenesis in the zebrafish hindbrain. Partial knockdown of Appb using antisense morpholino oligonucleotides blocked the formation of the Mauthner neurons, uni- or bilaterally, with an aberrant behavior as a consequence of this cellular change. The Appb morphants had decreased neurogenesis, increased notch signaling and notch1a expression at the expense of deltaA/D expression. The Mauthner cell development could be restored either by a general decrease in Notch signaling through γ-secretase inhibition or by a partial knock down of Notch1a. Together, this demonstrates the importance of Appb in neurogenesis and for the first time shows the essential requirement of Appb in the formation of a specific cell type, the Mauthner cell, in the hindbrain during development. Our results suggest that Appb-regulated neurogenesis is mediated through balancing the Notch1a signaling pathway and provide new insights into the development of the Mauthner cell.
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36
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Aguillon R, Blader P, Batut J. Patterning, morphogenesis, and neurogenesis of zebrafish cranial sensory placodes. Methods Cell Biol 2016; 134:33-67. [PMID: 27312490 DOI: 10.1016/bs.mcb.2016.01.002] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Peripheral sensory organs and ganglia found in the vertebrate head arise during embryonic development from distinct ectodermal thickenings, called cranial sensory placodes (adenohypophyseal, olfactory, lens, trigeminal, epibranchial, and otic). A series of patterning events leads to the establishment of these placodes. Subsequently, these placodes undergo specific morphogenetic movements and cell-type specification in order to shape the final placodal derivatives and to produce differentiated cell types necessary for their function. In this chapter, we will focus on recent studies in the zebrafish that have advanced our understanding of cranial sensory placode development. We will summarize the signaling events and their molecular effectors guiding the formation of the so-called preplacodal region, and the subsequent subdivision of this region along the anteroposterior axis that gives rise to specific placode identities as well as those controlling morphogenesis and neurogenesis. Finally, we will highlight the approaches used in zebrafish that have been established to precisely label cell populations, to follow their development, and/or to characterize cell fates within a specific placode.
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Affiliation(s)
- R Aguillon
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - P Blader
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
| | - J Batut
- Centre de Biologie du Développement (CBD, UMR5547), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, Toulouse, France
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37
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Xu J, Cui J, Del Campo A, Shin CH. Four and a Half LIM Domains 1b (Fhl1b) Is Essential for Regulating the Liver versus Pancreas Fate Decision and for β-Cell Regeneration. PLoS Genet 2016; 12:e1005831. [PMID: 26845333 PMCID: PMC4741517 DOI: 10.1371/journal.pgen.1005831] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Accepted: 01/06/2016] [Indexed: 12/12/2022] Open
Abstract
The liver and pancreas originate from overlapping embryonic regions, and single-cell lineage tracing in zebrafish has shown that Bone morphogenetic protein 2b (Bmp2b) signaling is essential for determining the fate of bipotential hepatopancreatic progenitors towards the liver or pancreas. Despite its pivotal role, the gene regulatory networks functioning downstream of Bmp2b signaling in this process are poorly understood. We have identified four and a half LIM domains 1b (fhl1b), which is primarily expressed in the prospective liver anlage, as a novel target of Bmp2b signaling. fhl1b depletion compromised liver specification and enhanced induction of pancreatic cells from endodermal progenitors. Conversely, overexpression of fhl1b favored liver specification and inhibited induction of pancreatic cells. By single-cell lineage tracing, we showed that fhl1b depletion led lateral endodermal cells, destined to become liver cells, to become pancreatic cells. Reversely, when fhl1b was overexpressed, medially located endodermal cells, fated to differentiate into pancreatic and intestinal cells, contributed to the liver by directly or indirectly modulating the discrete levels of pdx1 expression in endodermal progenitors. Moreover, loss of fhl1b increased the regenerative capacity of β-cells by increasing pdx1 and neurod expression in the hepatopancreatic ductal system. Altogether, these data reveal novel and critical functions of Fhl1b in the hepatic versus pancreatic fate decision and in β-cell regeneration. Lineage-specific multipotent progenitors play crucial roles in embryonic development, regeneration in adult tissues, and diseases such as cancer. Bone morphogenetic protein (Bmp) signaling is critical for regulating the cell fate choice of liver versus pancreas, two essential organs of body metabolism. Through transcriptome profiling of endodermal tissues exposed to increased or decreased Bmp2b signaling, we have discovered the zebrafish gene four and a half LIM domains 1b (fhl1b) as a novel target of Bmp2b signaling. fhl1b is primarily expressed in the prospective liver anlage. Loss- and gain-of-function analyses indicate that Fhl1b suppresses specification of the pancreas and induces the liver. By single-cell lineage tracing, we showed that depletion of fhl1b caused a liver-to-pancreas fate switch, while fhl1b overexpression redirected pancreatic progenitors to become liver cells. At later stages, Fhl1b regulates regeneration of insulin-secreting β-cells by directly or indirectly modulating pdx1 and neurod expression in the hepatopancreatic ductal system. Therefore, our work provides a novel paradigm of how Bmp signaling regulates the hepatic versus pancreatic fate decision and β-cell regeneration through its novel target Fhl1b.
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Affiliation(s)
- Jin Xu
- School of Biology and the Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, United States of America
| | - Jiaxi Cui
- Max Planck Institute for Polymer Research, Mainz, Germany
| | | | - Chong Hyun Shin
- School of Biology and the Parker H. Petit Institute for Bioengineering and Bioscience, Georgia Institute of Technology, Atlanta, Georgia, United States of America
- * E-mail:
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Stenkamp DL. Development of the Vertebrate Eye and Retina. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2015; 134:397-414. [PMID: 26310167 DOI: 10.1016/bs.pmbts.2015.06.006] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The mature, functional, and healthy eye is generated by the coordinated regulatory interaction of numerous and diverse developing tissues. The neural retina of the eye must undergo the neurogenesis of multiple retinal cell types in the correct ratios and spatial patterns. This chapter provides an overview of retinal development, and includes a summary of the process of eye organogenesis, a discussion of major principles of retinal neurogenesis, and describes some of the key molecular factors critical for retinal development. Defects in many of these factors underlie diseases of the eye, and an understanding of the process of retinal development will be critical for successful future applications of regenerative therapies for eye disease.
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Affiliation(s)
- Deborah L Stenkamp
- Department of Biological Sciences, University of Idaho, Moscow, Idaho, USA.
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Sato T, Sato F, Kamezaki A, Sakaguchi K, Tanigome R, Kawakami K, Sehara-Fujisawa A. Neuregulin 1 Type II-ErbB Signaling Promotes Cell Divisions Generating Neurons from Neural Progenitor Cells in the Developing Zebrafish Brain. PLoS One 2015; 10:e0127360. [PMID: 26001123 PMCID: PMC4441363 DOI: 10.1371/journal.pone.0127360] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Accepted: 04/14/2015] [Indexed: 02/03/2023] Open
Abstract
Post-mitotic neurons are generated from neural progenitor cells (NPCs) at the expense of their proliferation. Molecular and cellular mechanisms that regulate neuron production temporally and spatially should impact on the size and shape of the brain. While transcription factors such as neurogenin1 (neurog1) and neurod govern progression of neurogenesis as cell-intrinsic mechanisms, recent studies show regulatory roles of several cell-extrinsic or intercellular signaling molecules including Notch, FGF and Wnt in production of neurons/neural progenitor cells from neural stem cells/radial glial cells (NSCs/RGCs) in the ventricular zone (VZ). However, it remains elusive how production of post-mitotic neurons from neural progenitor cells is regulated in the sub-ventricular zone (SVZ). Here we show that newborn neurons accumulate in the basal-to-apical direction in the optic tectum (OT) of zebrafish embryos. While neural progenitor cells are amplified by mitoses in the apical ventricular zone, neurons are exclusively produced through mitoses of neural progenitor cells in the sub-basal zone, later in the sub-ventricular zone, and accumulate apically onto older neurons. This neurogenesis depends on Neuregulin 1 type II (NRG1-II)-ErbB signaling. Treatment with an ErbB inhibitor, AG1478 impairs mitoses in the sub-ventricular zone of the optic tectum. Removal of AG1478 resumes sub-ventricular mitoses without precedent mitoses in the apical ventricular zone prior to basal-to-apical accumulation of neurons, suggesting critical roles of ErbB signaling in mitoses for post-mitotic neuron production. Knockdown of NRG1-II impairs both mitoses in the sub-basal/sub-ventricular zone and the ventricular zone. Injection of soluble human NRG1 into the developing brain ameliorates neurogenesis of NRG1-II-knockdown embryos, suggesting a conserved role of NRG1 as a cell-extrinsic signal. From these results, we propose that NRG1-ErbB signaling stimulates cell divisions generating neurons from neural progenitor cells in the developing vertebrate brain.
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Affiliation(s)
- Tomomi Sato
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
- * E-mail: (TS); (ASF)
| | - Fuminori Sato
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Aosa Kamezaki
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
- Laboratory of Molecular Cell Biology and Development, Graduate School of Biostudies, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Kazuya Sakaguchi
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Ryoma Tanigome
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
| | - Koichi Kawakami
- Division of Molecular and Developmental Biology, National Institute of Genetics, Mishima-shi, Shizuoka, Japan
| | - Atsuko Sehara-Fujisawa
- Department of Growth Regulation, Institute for Frontier Medical Sciences, Kyoto University, Sakyo-ku, Kyoto, Japan
- * E-mail: (TS); (ASF)
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Lara-Ramírez R, Patthey C, Shimeld SM. Characterization of twoneurogeningenes from the brook lampreylampetra planeriand their expression in the lamprey nervous system. Dev Dyn 2015; 244:1096-1108. [DOI: 10.1002/dvdy.24273] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Revised: 01/29/2015] [Accepted: 02/16/2015] [Indexed: 11/10/2022] Open
Affiliation(s)
- Ricardo Lara-Ramírez
- Department of Zoology; The Tinbergen Building, University of Oxford; South Parks Road Oxford United Kingdom
| | - Cédric Patthey
- Department of Zoology; The Tinbergen Building, University of Oxford; South Parks Road Oxford United Kingdom
- Umeå Centre for Molecular Medicine, Umeå University; Umeå Sweden
| | - Sebastian M. Shimeld
- Department of Zoology; The Tinbergen Building, University of Oxford; South Parks Road Oxford United Kingdom
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Lutte AH, Capiotti KM, da Silva NLG, da Silva CSDO, Kist LW, Bogo MR, Da Silva RS. Contributions from extracellular sources of adenosine to the ethanol toxicity in zebrafish larvae. Reprod Toxicol 2015; 53:82-91. [PMID: 25883026 DOI: 10.1016/j.reprotox.2015.04.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 03/13/2015] [Accepted: 04/03/2015] [Indexed: 12/21/2022]
Abstract
The effects of ethanol exposure on extracellular adenosine sources in zebrafish were evaluated. In the acute treatment, the embryos were exposed to 2% ethanol on day 1 post-fertilization (dpf). In the chronic treatment, the exposure was continued for 2h/day up to 6 dpf. Ecto-5'-nucleotidase activity was assessed by colorimetric method and gene expression determined by RT-qPCR in 7 dpf zebrafish. Body length, ocular distance and surface area of the eyes were registered in animals acutely exposed to ethanol and pretreated with AOPCP (5-500 nM), an ecto-5'-nucleotidase inhibitor, or dipyridamole (10-100 μM), a blocker of nucleoside transport. Both ethanol exposures promoted increased ecto-5'-nucleotidase activity, impaired locomotion and morphology. Ecto-5'-nucleotidase expression was not affected. AOPCP promoted mild prevention of morphological defects caused by acute treatment, while dipyridamole worsened these defects. Early ethanol exposure altered adenosinergic tonus, especially through nucleoside transporters, contributing to morphological defects produced by ethanol in zebrafish.
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Affiliation(s)
- Aline Haab Lutte
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Katiucia Marques Capiotti
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Nicole Luize Garcia da Silva
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Carolina Silveira de Oliveira da Silva
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Luiza Wilges Kist
- Laboratório de Biologia Genômica e Molecular, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, PUCRS, Porto Alegre, RS, Brazil
| | - Maurício Reis Bogo
- Laboratório de Biologia Genômica e Molecular, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, PUCRS, Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003, Porto Alegre, RS, Brazil
| | - Rosane Souza Da Silva
- Laboratório de Neuroquímica e Psicofarmacologia, Departamento de Biologia Celular e Molecular, Faculdade de Biociências, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil; Instituto Nacional de Ciência e Tecnologia Translacional em Medicina (INCT-TM), 90035-003, Porto Alegre, RS, Brazil.
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slc7a6os gene plays a critical role in defined areas of the developing CNS in zebrafish. PLoS One 2015; 10:e0119696. [PMID: 25803583 PMCID: PMC4372478 DOI: 10.1371/journal.pone.0119696] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 01/15/2015] [Indexed: 11/19/2022] Open
Abstract
The aim of this study is to shed light on the functional role of slc7a6os, a gene highly conserved in vertebrates. The Danio rerio slc7a6os gene encodes a protein of 326 amino acids with 46% identity to human SLC7A6OS and 14% to Saccharomyces cerevisiae polypeptide Iwr1. Yeast Iwr1 specifically binds RNA pol II, interacts with the basal transcription machinery and regulates the transcription of specific genes. In this study we investigated for the first time the biological role of SLC7A6OS in vertebrates. Zebrafish slc7a6os is a maternal gene that is expressed throughout development, with a prevalent localization in the developing central nervous system (CNS). The gene is also expressed, although at different levels, in various tissues of the adult fish. To determine the functional role of slc7a6os during zebrafish development, we knocked-down the gene by injecting a splice-blocking morpholino. At 24 hpf morphants show morphological defects in the CNS, particularly the interface between hindbrain and midbrain is not well-defined. At 28 hpf the morpholino injected embryos present an altered somite morphology and appear partially or completely immotile. At this stage the midbrain, hindbrain and cerebellum are compromised and not well defined compared with control embryos. The observed alterations persist at later developmental stages. Consistently, the expression pattern of two markers specifically expressed in the developing CNS, pax2a and neurod, is significantly altered in morphants. The co-injection of embryos with synthetic slc7a6os mRNA, rescues the morphant phenotype and restores the wild type expression pattern of pax2a and neurod. Our data suggest that slc7a6os might play a critical role in defined areas of the developing CNS in vertebrates, probably by regulating the expression of key genes.
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Abstract
Fibroblast growth factors (Fgfs) play important roles in developmental processes of the inner ear, including the ontogeny of the statoacoustic ganglia (SAG) and hair cells. However, the detailed genetic mechanism(s) underlying Fgf/Fgfr-dependent otic neural development remains elusive. Using conditional genetic approaches and inhibitory small molecules, we have revealed that Fgfr-PI3K/Akt signaling is mainly responsible for zebrafish SAG development and have determined that Sox9a and Atoh1a act downstream of Fgfr-Akt signaling to specify and/or maintain the otic neuron fate during the early segmentation stage. Sox9a and Atoh1a coregulate numerous downstream factors identified through our ChIP-seq analyses, including Tlx2 and Eya2. Fgfr-Erk1/2 signaling contributes to ultricular hair cell development during a critical period between 9 and 15 hours postfertilization. Our work reveals that a genetic network of the previously known sensory determinant Atoh1 and the neural crest determinant Sox9 plays critical roles in SAG development. These newly uncovered roles for Atoh1and Sox9 in zebrafish otic development may be relevant to study in other species.
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Tfap2a promotes specification and maturation of neurons in the inner ear through modulation of Bmp, Fgf and notch signaling. PLoS Genet 2015; 11:e1005037. [PMID: 25781991 PMCID: PMC4364372 DOI: 10.1371/journal.pgen.1005037] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 01/28/2015] [Indexed: 11/23/2022] Open
Abstract
Neurons of the statoacoustic ganglion (SAG) transmit auditory and vestibular information from the inner ear to the hindbrain. SAG neuroblasts originate in the floor of the otic vesicle. New neuroblasts soon delaminate and migrate towards the hindbrain while continuing to proliferate, a phase known as transit amplification. SAG cells eventually come to rest between the ear and hindbrain before terminally differentiating. Regulation of these events is only partially understood. Fgf initiates neuroblast specification within the ear. Subsequently, Fgf secreted by mature SAG neurons exceeds a maximum threshold, serving to terminate specification and delay maturation of transit-amplifying cells. Notch signaling also limits SAG development, but how it is coordinated with Fgf is unknown. Here we show that transcription factor Tfap2a coordinates multiple signaling pathways to promote neurogenesis in the zebrafish inner ear. In both zebrafish and chick, Tfap2a is expressed in a ventrolateral domain of the otic vesicle that includes neurogenic precursors. Functional studies were conducted in zebrafish. Loss of Tfap2a elevated Fgf and Notch signaling, thereby inhibiting SAG specification and slowing maturation of transit-amplifying cells. Conversely, overexpression of Tfap2a inhibited Fgf and Notch signaling, leading to excess and accelerated SAG production. However, most SAG neurons produced by Tfap2a overexpression died soon after maturation. Directly blocking either Fgf or Notch caused less dramatic acceleration of SAG development without neuronal death, whereas blocking both pathways mimicked all observed effects of Tfap2a overexpression, including apoptosis of mature neurons. Analysis of genetic mosaics showed that Tfap2a acts non-autonomously to inhibit Fgf. This led to the discovery that Tfap2a activates expression of Bmp7a, which in turn inhibits both Fgf and Notch signaling. Blocking Bmp signaling reversed the effects of overexpressing Tfap2a. Together, these data support a model in which Tfap2a, acting through Bmp7a, modulates Fgf and Notch signaling to control the duration, amount and speed of SAG neural development. Neurons of the statoacoustic ganglion (SAG) transmit impulses from the inner ear necessary for hearing and balance. SAG cells exhibit a complex pattern of development, regulation of which remains poorly understood. Here we show that transcription factor Tfap2a coordinates multiple cell signaling pathways needed to regulate the quantity and pace of SAG neuron production. SAG progenitors originate within the developing inner ear and then migrate out of the ear towards the hindbrain before forming mature neurons. We showed previously that Fgf initiates formation of SAG progenitors in the inner ear, but rising levels of Fgf signaling eventually terminate this process. Elevated Fgf also stimulates proliferation of SAG progenitors outside the ear and delays their maturation. Notch signaling is also known to limit SAG development. Tfap2a governs the strength of Fgf and Notch signaling by activating expression of Bmp7a, which inhibits Fgf and Notch. Together these signals stabilize the pool of SAG progenitors outside the ear by equalizing rates of maturation and proliferation. This balance is critical for sustained accumulation of SAG neurons during larval growth as well as regeneration following neural damage. These findings could inform development of stem cell therapies to correct auditory neuropathies in humans.
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Ristori E, Lopez-Ramirez MA, Narayanan A, Hill-Teran G, Moro A, Calvo CF, Thomas JL, Nicoli S. A Dicer-miR-107 Interaction Regulates Biogenesis of Specific miRNAs Crucial for Neurogenesis. Dev Cell 2015; 32:546-60. [PMID: 25662174 DOI: 10.1016/j.devcel.2014.12.013] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2014] [Revised: 10/16/2014] [Accepted: 12/17/2014] [Indexed: 01/07/2023]
Abstract
Dicer controls the biogenesis of microRNAs (miRNAs) and is essential for neurogenesis. Recent reports show that the levels and substrate selectivity of DICER result in the preferential biogenesis of specific miRNAs in vitro. However, how dicer expression levels and miRNA biogenesis are regulated in vivo and how this affects neurogenesis is incompletely understood. Here we show that during zebrafish hindbrain development dicer expression levels are controlled by miR-107 to tune the biogenesis of specific miRNAs, such as miR-9, whose levels regulate neurogenesis. Loss of miR-107 function stabilizes dicer levels and miR-9 biogenesis across the ventricular hindbrain zone, resulting in an increase of both proliferating progenitors and postmitotic neurons. miR-9 ectopic accumulation in differentiating neuronal cells recapitulated the excessive neurogenesis phenotype. We propose that miR-107 modulation of dicer levels in differentiating neuronal cells is required to maintain the homeostatic levels of specific miRNAs, whose precise accumulation is essential for neurogenesis.
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Affiliation(s)
- Emma Ristori
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA
| | | | - Anand Narayanan
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA
| | - Guillermina Hill-Teran
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA
| | - Albertomaria Moro
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA
| | - Charles-Félix Calvo
- University Pierre et Marie Curie-Paris 6, Centre de Recherche de l'Institut du Cerveau et de la Moelle Epiniere, UMR S975, Paris 75651, France; INSERM/CNRS U-1127/UMR-7225, Paris 75651, France; AP-HP, Groupe Hospitalier Pitié-Salpètrière, Paris 75651, France
| | - Jean-Léon Thomas
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA; University Pierre et Marie Curie-Paris 6, Centre de Recherche de l'Institut du Cerveau et de la Moelle Epiniere, UMR S975, Paris 75651, France; INSERM/CNRS U-1127/UMR-7225, Paris 75651, France; AP-HP, Groupe Hospitalier Pitié-Salpètrière, Paris 75651, France
| | - Stefania Nicoli
- Yale Cardiovascular Research Center, Internal Medicine, Yale University, New Haven, CT 06511, USA.
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Casari A, Schiavone M, Facchinello N, Vettori A, Meyer D, Tiso N, Moro E, Argenton F. A Smad3 transgenic reporter reveals TGF-beta control of zebrafish spinal cord development. Dev Biol 2014; 396:81-93. [DOI: 10.1016/j.ydbio.2014.09.025] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2014] [Revised: 09/01/2014] [Accepted: 09/17/2014] [Indexed: 11/25/2022]
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Chen MHC, Hsu LC, Wu JL, Yeh CW, Tsai JN, Hseu YC, Hsu LS. Exposure to benzidine caused apoptosis and malformation of telencephalon region in zebrafish. ENVIRONMENTAL TOXICOLOGY 2014; 29:1428-1436. [PMID: 23766236 DOI: 10.1002/tox.21873] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2013] [Revised: 04/16/2013] [Accepted: 05/03/2013] [Indexed: 06/02/2023]
Abstract
Exposure to benzidine has been known to induce human cancers, particularly bladder carcinomas. In this study, the zebrafish model was used to investigate the developmental toxicity of benzidine. Embryos at 6 h postfertilization (hpf) that were exposed to benzidine exhibited embryonic death in a dose- and time-dependent manner. Benzidine induced malformations in zebrafish, such as small brain development, shorter axes, and a slight pericardial edema. High concentrations (50, 100, and 200 µM) of benzidine triggered widespread apoptosis in the brain and dorsal neurons, as evidenced by acridine orange and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assays. Real-time polymerase chain reaction analysis also showed that benzidine treatment affected p53, bax, and noxa expression. Decreases in specific brain markers, such as emx1 in the telencephalon, ngn1 in differentiated neurons, and otx2 in the midbrain, were observed in benzidine-treated embryos at 24 hpf. Conversely, no overt changes to pax2.1 expression in the midbrain-hindbrain boundary were found. Moreover, the use of Tg(HuC:GFP) zebrafish showed that benzidine caused a malformation of the telencephalon region. Our findings show that benzidine exposure triggers widespread apoptosis in the zebrafish brain and dorsal neurons, resulting in the development of an abnormal telencephalon.
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Miyake A, Chitose T, Kamei E, Murakami A, Nakayama Y, Konishi M, Itoh N. Fgf16 is required for specification of GABAergic neurons and oligodendrocytes in the zebrafish forebrain. PLoS One 2014; 9:e110836. [PMID: 25357195 PMCID: PMC4214708 DOI: 10.1371/journal.pone.0110836] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 09/24/2014] [Indexed: 11/18/2022] Open
Abstract
Fibroblast growth factor (Fgf) signaling plays crucial roles in various developmental processes including those in the brain. We examined the role of Fgf16 in the formation of the zebrafish brain. The knockdown of fgf16 decreased cell proliferation in the forebrain and midbrain. fgf16 was also essential for development of the ventral telencephalon and diencephalon, whereas fgf16 was not required for dorsoventral patterning in the midbrain. fgf16 was additionally required for the specification and differentiation of γ-aminobutyric acid (GABA)ergic interneurons and oligodendrocytes, but not for those of glutamatergic neurons in the forebrain. Cross talk between Fgf and Hedgehog (Hh) signaling was critical for the specification of GABAergic interneurons and oligodendrocytes. The expression of fgf16 in the forebrain was down-regulated by the inhibition of Hh and Fgf19 signaling, but not by that of Fgf3/Fgf8 signaling. The fgf16 morphant phenotype was similar to that of the fgf19 morphant and embryos blocked Hh signaling. The results of the present study indicate that Fgf16 signaling, which is regulated by the downstream pathways of Hh-Fgf19 in the forebrain, is involved in forebrain development.
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Affiliation(s)
- Ayumi Miyake
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
- * E-mail:
| | - Tatsuya Chitose
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
| | - Eriko Kamei
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
| | - Atsuko Murakami
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
| | - Yoshiaki Nakayama
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
| | - Morichika Konishi
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
| | - Nobuyuki Itoh
- Department of Genetic Biochemistry, Kyoto University Graduate School of Pharmaceutical Sciences, Sakyo, Kyoto, Japan
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Dyer C, Linker C, Graham A, Knight R. Specification of sensory neurons occurs through diverse developmental programs functioning in the brain and spinal cord. Dev Dyn 2014; 243:1429-39. [PMID: 25179866 DOI: 10.1002/dvdy.24184] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Revised: 08/11/2014] [Accepted: 08/18/2014] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND Vertebrates possess two populations of sensory neurons located within the central nervous system: Rohon-Beard (RB) and mesencephalic trigeminal nucleus (MTN) neurons. RB neurons are transient spinal cord neurons whilst MTN neurons are the proprioceptive cells that innervate the jaw muscles. It has been suggested that MTN and RB neurons share similarities and may have a common developmental program, but it is unclear how similar or different their development is. RESULTS We have dissected RB and MTN neuronal specification in zebrafish. We find that RB and MTN neurons express a core set of genes indicative of sensory neurons, but find these are also expressed by adjacent diencephalic neurons. Unlike RB neurons, our evidence argues against a role for the neural crest during MTN development. We additionally find that neurogenin1 function is dispensable for MTN differentiation, unlike RB cells and all other sensory neurons. Finally, we demonstrate that, although Notch signalling is involved in RB development, it is not involved in the generation of MTN cells. CONCLUSIONS Our work reveals fundamental differences between the development of MTN and RB neurons and suggests that these populations are non-homologous and thus have distinct developmental and, probably, evolutionary origins.
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Affiliation(s)
- Carlene Dyer
- Department of Craniofacial Development and Stem Cell Biology, King's College London, London, United Kingdom
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Dozawa M, Kono H, Sato Y, Ito Y, Tanaka H, Ohshima T. Valproic acid, a histone deacetylase inhibitor, regulates cell proliferation in the adult zebrafish optic tectum. Dev Dyn 2014; 243:1401-15. [PMID: 25091230 DOI: 10.1002/dvdy.24173] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2013] [Revised: 06/29/2014] [Accepted: 07/02/2014] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Valproic acid (VPA) has been used to treat epilepsy and bipolar disorder. Several reports have demonstrated that VPA functions as a histone deacetylase (HDAC) inhibitor. While VPA is known to cause teratogenic changes in the embryonic zebrafish brain, its effects on neural stem cells (NSCs) in both the embryonic and adult zebrafish are not well understood. RESULTS In this study, we observed a proliferative effect of VPA on NSCs in the embryonic hindbrain. In contrast, VPA reduced cell proliferation in the adult zebrafish optic tectum. Treatment with HDAC inhibitors showed a similar inhibitory effect on cell proliferation in the adult zebrafish optic tectum, suggesting that VPA reduces cell proliferation through HDAC inhibition. Cell cycle progression was also suppressed in the optic tectum of the adult zebrafish brain because of HDAC inhibition. Recent studies have demonstrated that HDAC inhibits the Notch signaling pathway; hence, adult zebrafish were treated with a Notch inhibitor. This increased the number of proliferating cells in the adult zebrafish optic tectum with down-regulated expression of her4, a target of Notch signaling. CONCLUSIONS These results suggest that VPA inhibits HDAC activity and upregulates Notch signaling to reduce cell proliferation in the optic tectum of adult zebrafish.
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Affiliation(s)
- Miki Dozawa
- Department of Life Science and Medical Bio-Science, School of Advanced Science and Engineering, Waseda University, Tokyo, Japan
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