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Taylor R, Houart C. Optimized Primary Culture of Neuronal Populations for Subcellular Omics Applications. Methods Mol Biol 2024; 2707:113-124. [PMID: 37668908 DOI: 10.1007/978-1-0716-3401-1_7] [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] [Indexed: 09/06/2023]
Abstract
Primary cell culture is an invaluable method frequently used to overcome challenges associated with in vivo experiments. In zebrafish research, in vivo live imaging experiments are routine owing to the high optical transparency of embryos, and, as a result, primary cell culture has been less utilized. However, the approach still boasts powerful advantages, emphasizing the importance of sophisticated zebrafish cell culture protocols. Here, we present an enhanced protocol for the generation of primary cell cultures by dissociation of 24 hpf zebrafish embryos. We include a novel cell culture medium recipe specifically favoring neuronal growth and survival, enabling relatively long-term culture. We outline primary zebrafish neuronal culture on glass coverslips, as well as in transwell inserts which allow isolation of neurite tissue for experiments such as investigating subcellular transcriptomes.
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Affiliation(s)
- Richard Taylor
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK.
| | - Corinne Houart
- Centre for Developmental Neurobiology and MRC Centre for Neurodevelopmental Disorders, King's College London, London, UK.
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2
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Ibrahim M, Xie B, Richardson MK. The growth of endothelial-like cells in zebrafish embryoid body culture. Exp Cell Res 2020; 392:112032. [PMID: 32353375 DOI: 10.1016/j.yexcr.2020.112032] [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: 04/17/2020] [Accepted: 04/21/2020] [Indexed: 11/25/2022]
Abstract
There is increasing interest in the possibility of culturing organ-like tissues (organoids) in vitro for biomedical applications. The ability to culture organoids would be greatly enhanced by having a functional circulation in vitro. The endothelial cell is the most important cell type in this context. Endothelial cells can be derived from pluripotent embryonic blastocyst cells in aggregates called embryoid bodies. Here, we examine the yield of endothelial-like cells in embryoid bodies (EBs) developed from transgenic zebrafish fli:GFP and kdrl:GFP blastocyst embryos. The isolated blastocyst cells developed into EBs within the first 24 h of culture and contained fli:GFP+ (putative endothelial, hematopoietic and other cell types); or kdrl:GFP+ (endothelial) cells. The addition of endothelial growth supplements to the media and culture on collagen type-I substratum increased the percentages of fli:GFP+ and kdrl:GFP+ cells in culture. We found that EBs developed in hanging-drop cultures possessed a higher percentage of fli:GFP+ (45.0 ± 3.1%) and kdrl:GFP+ cells (8.7 ± 0.7%) than those developed on conventional substrata (34.5 ± 1.4% or 5.2 ± 0.4%, respectively). The transcriptome analysis showed a higher expression of VEGF and TGFβ genes in EB cultures compared to the adherent cultures. When transferred to conventional culture, the percentage of fli:GFP+ or kdrl:GFP+ cells declined significantly over subsequent days in the EBs. The fli:GFP+ cells formed a monolayer around the embryoid bodies, while the kdrl:GFP+ cells formed vascular network-like structures in the embryoid bodies. Differences were observed in the spreading of fli:GFP+ cells, and network formation of kdrl:GFP+ cells on different substrates. The fli:GFP+ cells could be maintained in primary culture and sub-cultures. By contrast, kdrl:GFP+ cells were almost completely absent at 8d of primary culture. Our culture model allows real-time observation of fli:GFP+ and kdrl:GFP+ cells in culture. The results obtained from this study will be important for the development of vascular and endothelial cell culture using embryonic cells.
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Affiliation(s)
- Muhammad Ibrahim
- Institute of Biology Leiden, Leiden University, The Netherlands; Animal Biotechnology Division, Institute of Biotechnology and Genetic Engineering, The University of Agriculture Peshawar, Pakistan
| | - Bing Xie
- Institute of Biology Leiden, Leiden University, The Netherlands
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3
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Pitchai A, Rajaretinam RK, Freeman JL. Zebrafish as an Emerging Model for Bioassay-Guided Natural Product Drug Discovery for Neurological Disorders. MEDICINES (BASEL, SWITZERLAND) 2019; 6:E61. [PMID: 31151179 PMCID: PMC6631710 DOI: 10.3390/medicines6020061] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2019] [Revised: 05/26/2019] [Accepted: 05/27/2019] [Indexed: 02/06/2023]
Abstract
Most neurodegenerative diseases are currently incurable, with large social and economic impacts. Recently, there has been renewed interest in investigating natural products in the modern drug discovery paradigm as novel, bioactive small molecules. Moreover, the discovery of potential therapies for neurological disorders is challenging and involves developing optimized animal models for drug screening. In contemporary biomedicine, the growing need to develop experimental models to obtain a detailed understanding of malady conditions and to portray pioneering treatments has resulted in the application of zebrafish to close the gap between in vitro and in vivo assays. Zebrafish in pharmacogenetics and neuropharmacology are rapidly becoming a widely used organism. Brain function, dysfunction, genetic, and pharmacological modulation considerations are enhanced by both larval and adult zebrafish. Bioassay-guided identification of natural products using zebrafish presents as an attractive strategy for generating new lead compounds. Here, we see evidence that the zebrafish's central nervous system is suitable for modeling human neurological disease and we review and evaluate natural product research using zebrafish as a vertebrate model platform to systematically identify bioactive natural products. Finally, we review recently developed zebrafish models of neurological disorders that have the potential to be applied in this field of research.
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Affiliation(s)
- Arjun Pitchai
- Molecular and Nanomedicine Research Unit (MNRU), Centre for Nanoscience and Nanotechnology (CNSNT), Sathyabama Institute of Science and Technology, Chennai 600119, Tamil Nadu, India.
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA.
| | - Rajesh Kannan Rajaretinam
- Molecular and Nanomedicine Research Unit (MNRU), Centre for Nanoscience and Nanotechnology (CNSNT), Sathyabama Institute of Science and Technology, Chennai 600119, Tamil Nadu, India.
| | - Jennifer L Freeman
- School of Health Sciences, Purdue University, West Lafayette, IN 47907, USA.
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4
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Acosta JR, Watchon M, Yuan KC, Fifita JA, Svahn AJ, Don EK, Winnick CG, Blair IP, Nicholson GA, Cole NJ, Goldsbury C, Laird AS. Neuronal cell culture from transgenic zebrafish models of neurodegenerative disease. Biol Open 2018; 7:bio.036475. [PMID: 30190267 PMCID: PMC6215410 DOI: 10.1242/bio.036475] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
We describe a protocol for culturing neurons from transgenic zebrafish embryos to investigate the subcellular distribution and protein aggregation status of neurodegenerative disease-causing proteins. The utility of the protocol was demonstrated on cell cultures from zebrafish that transgenically express disease-causing variants of human fused in sarcoma (FUS) and ataxin-3 proteins, in order to study amyotrophic lateral sclerosis (ALS) and spinocerebellar ataxia type-3 (SCA3), respectively. A mixture of neuronal subtypes, including motor neurons, exhibited differentiation and neurite outgrowth in the cultures. As reported previously, mutant human FUS was found to be mislocalized from nuclei to the cytosol, mimicking the pathology seen in human ALS and the zebrafish FUS model. In contrast, neurons cultured from zebrafish expressing human ataxin-3 with disease-associated expanded polyQ repeats did not accumulate within nuclei in a manner often reported to occur in SCA3. Despite this, the subcellular localization of the human ataxin-3 protein seen in cell cultures was similar to that found in the SCA3 zebrafish themselves. The finding of similar protein localization and aggregation status in the neuronal cultures and corresponding transgenic zebrafish models confirms that this cell culture model is a useful tool for investigating the cell biology and proteinopathy signatures of mutant proteins for the study of neurodegenerative disease. Summary: This article describes the optimization and validation of a protocol for culturing of neurons from transgenic zebrafish for the study of neurodegenerative diseases.
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Affiliation(s)
- Jamie R Acosta
- The Brain & Mind Centre, University of Sydney, Sydney, New South Wales 2050, Australia.,The Bosch Institute, University of Sydney, Sydney, New South Wales 2006, Australia.,Discipline of Anatomy and Histology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Maxinne Watchon
- Discipline of Anatomy and Histology, University of Sydney, Sydney, New South Wales 2006, Australia.,Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia.,Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Kristy C Yuan
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Jennifer A Fifita
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Adam J Svahn
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Emily K Don
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Claire G Winnick
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Ian P Blair
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Garth A Nicholson
- Sydney Medical School, University of Sydney, Sydney, New South Wales 2006, Australia.,Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia.,ANZAC Research Institute, Concord Repatriation Hospital, Sydney, New South Wales 2139, Australia
| | - Nicholas J Cole
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
| | - Claire Goldsbury
- The Brain & Mind Centre, University of Sydney, Sydney, New South Wales 2050, Australia.,The Bosch Institute, University of Sydney, Sydney, New South Wales 2006, Australia.,Discipline of Anatomy and Histology, University of Sydney, Sydney, New South Wales 2006, Australia
| | - Angela S Laird
- Centre for Motor Neuron Disease Research, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, Macquarie University, Sydney, New South Wales 2109, Australia
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5
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Ibrahim M, Richardson MK. Beyond organoids: In vitro vasculogenesis and angiogenesis using cells from mammals and zebrafish. Reprod Toxicol 2017; 73:292-311. [PMID: 28697965 DOI: 10.1016/j.reprotox.2017.07.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/12/2017] [Accepted: 07/05/2017] [Indexed: 12/24/2022]
Abstract
The ability to culture complex organs is currently an important goal in biomedical research. It is possible to grow organoids (3D organ-like structures) in vitro; however, a major limitation of organoids, and other 3D culture systems, is the lack of a vascular network. Protocols developed for establishing in vitro vascular networks typically use human or rodent cells. A major technical challenge is the culture of functional (perfused) networks. In this rapidly advancing field, some microfluidic devices are now getting close to the goal of an artificially perfused vascular network. Another development is the emergence of the zebrafish as a complementary model to mammals. In this review, we discuss the culture of endothelial cells and vascular networks from mammalian cells, and examine the prospects for using zebrafish cells for this objective. We also look into the future and consider how vascular networks in vitro might be successfully perfused using microfluidic technology.
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Affiliation(s)
- Muhammad Ibrahim
- Animal Science and Health Cluster, Institute of Biology Leiden, Leiden University, The Netherlands; Institute of Biotechnology and Genetic Engineering, The University of Agriculture, Peshawar, Pakistan
| | - Michael K Richardson
- Animal Science and Health Cluster, Institute of Biology Leiden, Leiden University, The Netherlands.
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6
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In vitro development of zebrafish vascular networks. Reprod Toxicol 2017; 70:102-115. [DOI: 10.1016/j.reprotox.2017.02.008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Revised: 01/27/2017] [Accepted: 02/08/2017] [Indexed: 12/28/2022]
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7
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Abstract
Zebrafish embryonic cell cultures have many useful properties that make them complementary to intact embryos for a wide range of studies. Embryonic cell cultures allow for maintenance of transient cell populations, control of chemical and mechanical cues received by cells, and facile chemical screening. Zebrafish cells can be cultured in either heterogeneous or homogeneous cultures from a wide range of developmental time points. Here we describe two methods with particular applicability to chemical screening: a method for the culture of blastomeres for directed differentiation toward the myogenic lineage and a method for the culture of neural crest cells in heterogeneous cultures from early somitogenesis embryos.
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Affiliation(s)
- C A Ciarlo
- Harvard Medical School and Children's Hospital, Boston, MA, United States
| | - L I Zon
- Children's Hospital and Dana Farber Cancer Institute, Boston, MA, United States; Harvard University, Cambridge, MA, United States
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8
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Geach TJ, Hirst EMA, Zimmerman LB. Contractile activity is required for Z-disc sarcomere maturation in vivo. Genesis 2015; 53:299-307. [PMID: 25845369 PMCID: PMC4676352 DOI: 10.1002/dvg.22851] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2015] [Revised: 03/30/2015] [Accepted: 03/31/2015] [Indexed: 01/16/2023]
Abstract
Sarcomere structure underpins structural integrity, signaling, and force transmission in the muscle. In embryos of the frog Xenopus tropicalis, muscle contraction begins even while sarcomerogenesis is ongoing. To determine whether contractile activity plays a role in sarcomere formation in vivo, chemical tools were used to block acto-myosin contraction in embryos of the frog X. tropicalis, and Z-disc assembly was characterized in the paralyzed dicky ticker mutant. Confocal and ultrastructure analysis of paralyzed embryos showed delayed Z-disc formation and defects in thick filament organization. These results suggest a previously undescribed role for contractility in sarcomere maturation in vivo. genesis 53:299–307, 2015. © 2015 The Authors. Genesis Published by Wiley Periodicals, Inc.
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Affiliation(s)
- Timothy J Geach
- Division of Developmental Biology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Elizabeth M A Hirst
- Division of Developmental Biology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
| | - Lyle B Zimmerman
- Division of Developmental Biology, MRC National Institute for Medical Research, The Ridgeway, Mill Hill, London, United Kingdom
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9
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Myhre JL, Hills JA, Prill K, Wohlgemuth SL, Pilgrim DB. The titin A-band rod domain is dispensable for initial thick filament assembly in zebrafish. Dev Biol 2013; 387:93-108. [PMID: 24370452 DOI: 10.1016/j.ydbio.2013.12.020] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2013] [Revised: 12/11/2013] [Accepted: 12/13/2013] [Indexed: 01/19/2023]
Abstract
The sarcomeres of skeletal and cardiac muscle are highly structured protein arrays, consisting of thick and thin filaments aligned precisely to one another and to their surrounding matrix. The contractile mechanisms of sarcomeres are generally well understood, but how the patterning of sarcomeres is initiated during early skeletal muscle and cardiac development remains uncertain. Two of the most widely accepted hypotheses for this process include the "molecular ruler" model, in which the massive protein titin defines the length of the sarcomere and provides a scaffold along which the myosin thick filament is assembled, and the "premyofibril" model, which proposes that thick filament formation does not require titin, but that a "premyofibril" consisting of non-muscle myosin, α-actinin and cytoskeletal actin is used as a template. Each model posits a different order of necessity of the various components, but these have been difficult to test in vivo. Zebrafish motility mutants with developmental defects in sarcomere patterning are useful for the elucidation of such mechanisms, and here we report the analysis of the herzschlag mutant, which shows deficits in both cardiac and skeletal muscle. The herzschlag mutant produces a truncated titin protein, lacking the C-terminal rod domain that is proposed to act as a thick filament scaffold, yet muscle patterning is still initiated, with grossly normal thick and thin filament assembly. Only after embryonic muscle contraction begins is breakdown of sarcomeric myosin patterning observed, consistent with the previously noted role of titin in maintaining the contractile integrity of mature sarcomeres. This conflicts with the "molecular ruler" model of early sarcomere patterning and supports a titin-independent model of thick filament organization during sarcomerogenesis. These findings are also consistent with the symptoms of human titin myopathies that exhibit a late onset, such as tibial muscular dystrophy.
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Affiliation(s)
- J Layne Myhre
- Department of Biological Sciences, CW405, Biological Sciences Building, University of Alberta, Edmonton, Canada AB T6G 2E9
| | - Jordan A Hills
- Department of Biological Sciences, CW405, Biological Sciences Building, University of Alberta, Edmonton, Canada AB T6G 2E9
| | - Kendal Prill
- Department of Biological Sciences, CW405, Biological Sciences Building, University of Alberta, Edmonton, Canada AB T6G 2E9
| | - Serene L Wohlgemuth
- Department of Biological Sciences, CW405, Biological Sciences Building, University of Alberta, Edmonton, Canada AB T6G 2E9
| | - David B Pilgrim
- Department of Biological Sciences, CW405, Biological Sciences Building, University of Alberta, Edmonton, Canada AB T6G 2E9.
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10
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Lin CY, Chen JS, Loo MR, Hsiao CC, Chang WY, Tsai HJ. MicroRNA-3906 regulates fast muscle differentiation through modulating the target gene homer-1b in zebrafish embryos. PLoS One 2013; 8:e70187. [PMID: 23936160 PMCID: PMC3729524 DOI: 10.1371/journal.pone.0070187] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2013] [Accepted: 06/17/2013] [Indexed: 01/22/2023] Open
Abstract
A microRNA, termed miR-In300 or miR-3906, suppresses the transcription of myf5 through silencing dickkopf-related protein 3 (dkk3r/dkk3a) during early development when myf5 is highly transcribed, but not at late stages when myf5 transcription is reduced. Moreover, after 24 hpf, when muscle cells are starting to differentiate, Dkk3a could not be detected in muscle tissue at 20 hpf. To explain these reversals, we collected embryos at 32 hpf, performed assays, and identified homer-1b, which regulates calcium release from sarcoplasmic reticulum, as the target gene of miR-3906. We further found that either miR-3906 knockdown or homer-1b overexpression increased expressions of fmhc4 and atp2a1 of calcium-dependent fast muscle fibrils, but not slow muscle fibrils, and caused a severe disruption of sarcomeric actin and Z-disc structure. Additionally, compared to control embryos, the intracellular calcium concentration ([Ca2+]i) of these treated embryos was increased as high as 83.9–97.3% in fast muscle. In contrast, either miR-3906 overexpression or homer-1b knockdown caused decreases of [Ca2+]i and, correspondingly, defective phenotypes in fast muscle. These defects could be rescued by inducing homer-1b expression at later stage. These results indicate that miR-3906 controls [Ca2+]i homeostasis in fast muscle through fine tuning homer-1b expression during differentiation to maintain normal muscle development.
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MESH Headings
- 3' Untranslated Regions/genetics
- Animals
- Animals, Genetically Modified
- Binding Sites/genetics
- Calcium/metabolism
- Cell Differentiation/genetics
- Embryo, Nonmammalian/cytology
- Embryo, Nonmammalian/embryology
- Embryo, Nonmammalian/metabolism
- Gene Expression Profiling
- Gene Expression Regulation, Developmental
- Gene Knockdown Techniques
- In Situ Hybridization
- MicroRNAs/genetics
- MicroRNAs/metabolism
- Microscopy, Electron, Transmission
- Muscle Fibers, Fast-Twitch/cytology
- Muscle Fibers, Fast-Twitch/metabolism
- Muscle, Skeletal/cytology
- Muscle, Skeletal/embryology
- Muscle, Skeletal/metabolism
- Mutation
- Oligonucleotide Array Sequence Analysis
- Reverse Transcriptase Polymerase Chain Reaction
- Sarcoplasmic Reticulum/metabolism
- Sarcoplasmic Reticulum/ultrastructure
- Zebrafish/embryology
- Zebrafish/genetics
- Zebrafish Proteins/genetics
- Zebrafish Proteins/metabolism
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Affiliation(s)
- Cheng-Yung Lin
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
| | - Jie-Shin Chen
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
| | - Moo-Rung Loo
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
| | - Chung-Ching Hsiao
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
| | - Wen-Yen Chang
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
| | - Huai-Jen Tsai
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
- * E-mail:
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11
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At the Start of the Sarcomere: A Previously Unrecognized Role for Myosin Chaperones and Associated Proteins during Early Myofibrillogenesis. Biochem Res Int 2012; 2012:712315. [PMID: 22400118 PMCID: PMC3287041 DOI: 10.1155/2012/712315] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Accepted: 10/10/2011] [Indexed: 01/03/2023] Open
Abstract
The development of striated muscle in vertebrates requires the assembly of contractile myofibrils, consisting of highly ordered bundles of protein filaments. Myofibril formation occurs by the stepwise addition of complex proteins, a process that is mediated by a variety of molecular chaperones and quality control factors. Most notably, myosin of the thick filament requires specialized chaperone activity during late myofibrillogenesis, including that of Hsp90 and its cofactor, Unc45b. Unc45b has been proposed to act exclusively as an adaptor molecule, stabilizing interactions between Hsp90 and myosin; however, recent discoveries in zebrafish and C. elegans suggest the possibility of an earlier role for Unc45b during myofibrillogenesis. This role may involve functional control of nonmuscle myosins during the earliest stages of myogenesis, when premyofibril scaffolds are first formed from dynamic cytoskeletal actin. This paper will outline several lines of evidence that converge to build a model for Unc45b activity during early myofibrillogenesis.
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12
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Li Z, Bhat N, Manali D, Wang D, Hong N, Yi M, Ge R, Hong Y. Medaka cleavage embryos are capable of generating ES-like cell cultures. Int J Biol Sci 2011; 7:418-25. [PMID: 21547059 PMCID: PMC3088284 DOI: 10.7150/ijbs.7.418] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2011] [Accepted: 04/01/2011] [Indexed: 12/11/2022] Open
Abstract
Mammalian embryos at the blastocyst stage have three major lineages, which in culture can give rise to embryonic stem (ES) cells from the inner cell mass or epiblast, trophoblast stem cells from the trophectoderm, and primitive endoderm stem cells. None of these stem cells is totipotent, because they show gene expression profiles characteristic of their sources and usually contribute only to the lineages of their origins in chimeric embryos. It is unknown whether embryos prior to the blastocyst stage can be cultivated towards totipotent stem cell cultures. Medaka is an excellent model for stem cell research. This laboratory fish has generated diploid and even haploid ES cells from the midblastula embryo with ~2000 cells. Here we report in medaka that dispersed cells from earlier embryos can survive, proliferate and attach in culture. We show that even 32-cells embryos can be dissociated into individual cells capable of producing continuously growing ES-like cultures. Our data point to the possibility to derive stable cell culture from cleavage embryos in this organism.
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Affiliation(s)
- Zhendong Li
- Department of Biological Science, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260, Singapore
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