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Chandra B, Voas MG, Davies EL, Roberts-Galbraith RH. Ets-1 transcription factor regulates glial cell regeneration and function in planarians. Development 2023; 150:dev201666. [PMID: 37665145 PMCID: PMC10508700 DOI: 10.1242/dev.201666] [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: 02/01/2023] [Accepted: 08/15/2023] [Indexed: 09/05/2023]
Abstract
Glia play multifaceted roles in nervous systems in response to injury. Depending on the species, extent of injury and glial cell type in question, glia can help or hinder the regeneration of neurons. Studying glia in the context of successful regeneration could reveal features of pro-regenerative glia that could be exploited for new human therapies. Planarian flatworms completely regenerate their nervous systems after injury - including glia - and thus provide a strong model system for exploring glia in the context of regeneration. Here, we report that planarian glia regenerate after neurons, and that neurons are required for correct glial numbers and localization during regeneration. We also identify the planarian transcription factor-encoding gene ets-1 as a key regulator of glial cell maintenance and regeneration. Using ets-1 (RNAi) to perturb glia, we show that glial loss is associated with altered neuronal gene expression, impeded animal movement and impaired nervous system architecture - particularly within the neuropil. Importantly, our work reveals the inter-relationships of glia and neurons in the context of robust neural regeneration.
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Affiliation(s)
- Bidushi Chandra
- Department of Cellular Biology, University of Georgia, Athens, GA 30602, USA
| | - Matthew G. Voas
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
| | - Erin L. Davies
- Center for Cancer Research, National Cancer Institute, National Institutes of Health, Frederick, MD 21702, USA
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2
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Inoue T, Agata K. Quantification of planarian behaviors. Dev Growth Differ 2021; 64:16-37. [PMID: 34866186 DOI: 10.1111/dgd.12765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 10/06/2021] [Accepted: 10/23/2021] [Indexed: 11/30/2022]
Abstract
Research on individual behaviors can help to reveal the processes and mechanisms that mediate an animal's habits and interactions with the environment. Importantly, individual behaviors arise as outcomes of genetic programs, morphogenesis, physiological processes, and neural functions; thus, behavioral analyses can be used to detect disorders in these processes. Planarians belong to an early branching bilateral group of organisms that possess a simple central nervous system. Furthermore, planarians display various behavioral responses to the environment via their nervous system. Planarians also have remarkable regenerative abilities, including whole-brain regeneration. Therefore, the combination of planarians' phylogenetic position, behavioral properties, regenerative ability, and genetic accessibility provides a unique opportunity to understand the basic mechanisms underlying the anatomical properties of neural morphogenesis and the dynamic physiological processes and neural function. Here, we describe a step-by-step protocol for conducting simple behavioral analyses in planarians with the aim of helping to introduce researchers to the utility of performing behavioral analyses in planarians. Since the conditions of planarians impact experimental results and reproducibility, this protocol begins with a method for maintaining planarians. Next, we introduce the behavioral tests as well as the methods for quantifying them using minimal and cost-effective equipment and materials. Finally, we present a unique RNAi technique that enables conditional silencing of neural activity in the brain of planarians.
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Affiliation(s)
- Takeshi Inoue
- Division of Adaptation Physiology, Faculty of Medicine, Tottori University, Yonago, Japan
| | - Kiyokazu Agata
- National Institute for Basic Biology, National Institutes of Natural Sciences, Okazaki, Japan
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3
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Ziman B, Karabinis P, Barghouth P, Oviedo NJ. Sirtuin-1 regulates organismal growth by altering feeding behavior and intestinal morphology in planarians. J Cell Sci 2020; 133:jcs239467. [PMID: 32265271 PMCID: PMC7272345 DOI: 10.1242/jcs.239467] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 03/19/2020] [Indexed: 01/03/2023] Open
Abstract
Nutrient availability upon feeding leads to an increase in body size in the planarian Schmidtea mediterranea However, it remains unclear how food consumption integrates with cell division at the organismal level. Here, we show that the NAD-dependent protein deacetylases sirtuins are evolutionarily conserved in planarians, and specifically demonstrate that the homolog of human sirtuin-1 (SIRT1) (encoded by Smed-Sirt-1), regulates organismal growth by impairing both feeding behavior and intestinal morphology. Disruption of Smed-Sirt-1 with RNAi or pharmacological inhibition of Sirtuin-1 leads to reduced animal growth. Conversely, enhancement of Sirtuin-1 activity with resveratrol accelerates growth. Differences in growth rates were associated with changes in the amount of time taken to locate food and overall food consumption. Furthermore, Smed-Sirt-1(RNAi) animals displayed reduced cell death and increased stem cell proliferation accompanied by impaired expression of intestinal lineage progenitors and reduced branching of the gut. Taken together, our findings indicate that Sirtuin-1 is a crucial metabolic hub capable of controlling animal behavior, tissue renewal and morphogenesis of the adult intestine.
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Affiliation(s)
- Benjamin Ziman
- Department of Molecular and Cell Biology, University of California, Merced, CA 95343, USA
- Quantitative and Systems Biology Graduate Program, University of California, Merced, CA 95343, USA
| | - Peter Karabinis
- Department of Molecular and Cell Biology, University of California, Merced, CA 95343, USA
- Quantitative and Systems Biology Graduate Program, University of California, Merced, CA 95343, USA
| | - Paul Barghouth
- Department of Molecular and Cell Biology, University of California, Merced, CA 95343, USA
- Quantitative and Systems Biology Graduate Program, University of California, Merced, CA 95343, USA
| | - Néstor J Oviedo
- Department of Molecular and Cell Biology, University of California, Merced, CA 95343, USA
- Quantitative and Systems Biology Graduate Program, University of California, Merced, CA 95343, USA
- Health Sciences Research Institute, University of California, Merced, CA 95343, USA
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4
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Miyamoto M, Hattori M, Hosoda K, Sawamoto M, Motoishi M, Hayashi T, Inoue T, Umesono Y. The pharyngeal nervous system orchestrates feeding behavior in planarians. SCIENCE ADVANCES 2020; 6:eaaz0882. [PMID: 32285000 PMCID: PMC7141820 DOI: 10.1126/sciadv.aaz0882] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2019] [Accepted: 01/14/2020] [Indexed: 05/06/2023]
Abstract
Planarians exhibit traits of cephalization but are unique among bilaterians in that they ingest food by means of goal-directed movements of a trunk-positioned pharynx, following protrusion of the pharynx out of the body, raising the question of how planarians control such a complex set of body movements for achieving robust feeding. Here, we use the freshwater planarian Dugesia japonica to show that an isolated pharynx amputated from the planarian body self-directedly executes its entire sequence of feeding functions: food sensing, approach, decisions about ingestion, and intake. Gene-specific silencing experiments by RNA interference demonstrated that the pharyngeal nervous system (PhNS) is required not only for feeding functions of the pharynx itself but also for food-localization movements of individual animals, presumably via communication with the brain. These findings reveal an unexpected central role of the PhNS in the linkage between unique morphological phenotypes and feeding behavior in planarians.
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Affiliation(s)
- Mai Miyamoto
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Miki Hattori
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Kazutaka Hosoda
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Mika Sawamoto
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Minako Motoishi
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
| | - Tetsutaro Hayashi
- Laboratory for Bioinformatics Research, RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-minami, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - Takeshi Inoue
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo 171-8588, Japan
- Corresponding author. (Y.U.); (T.I.)
| | - Yoshihiko Umesono
- Graduate School of Life Science, University of Hyogo, 3-2-1 Kouto, Kamigori-cho, Ako-gun, Hyogo 678-1297, Japan
- Corresponding author. (Y.U.); (T.I.)
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5
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Mori M, Narahashi M, Hayashi T, Ishida M, Kumagai N, Sato Y, Bagherzadeh R, Agata K, Inoue T. Calcium ions in the aquatic environment drive planarians to food. ZOOLOGICAL LETTERS 2019; 5:31. [PMID: 31720007 PMCID: PMC6836377 DOI: 10.1186/s40851-019-0147-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2019] [Accepted: 10/21/2019] [Indexed: 05/08/2023]
Abstract
BACKGROUND Even subtle changes in environmental factors can exert behavioral effects on creatures, which may alter interspecific interactions and eventually affect the ecosystem. However, how changes in environmental factors impact complex behaviors regulated by neural processes is largely unknown. The freshwater planarian Dugesia japonica, a free-living flatworm, displays distinct behavioral traits mediated by sensitive perception of environmental cues. Planarians are thus useful organisms for examining interactions between environmental changes and specific behaviors of animals. RESULTS Here we found that feeding behavior was suppressed when the concentration of ions in the breeding water was low, while other behaviors were unaffected, resulting in differences in population size. Notably, the decline in feeding behavior was reversed in an ion-concentration-dependent manner soon after the planarians were moved to ion-containing water, which suggests that ions in environmental water rapidly promote feeding behavior in planarians. Moreover, the concentration of ions in the environmental water affected the feeding behavior by modulating the sensitivity of the response to foods. Finally, we found that calcium ions in the aquatic environment were required for the feeding behavior, and exposure to higher levels of calcium ions enhanced the feeding behavior, showing that there was a good correlation between the concentration of calcium ions and the responsiveness of planarians to foods. CONCLUSIONS Environmental calcium ions are indispensable for and potentiate the activity level of the feeding behavior of planarians. Our findings suggest that the ions in the aquatic environment profoundly impact the growth and survival of aquatic animals via modulating their neural activities and behaviors.
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Affiliation(s)
- Masato Mori
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
| | - Maria Narahashi
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
| | - Tetsutaro Hayashi
- Laboratory for Bioinformatics Research, RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-Minamimachi, Chuo-ku, Kobe, Japan
| | - Miyuki Ishida
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
| | - Nobuyoshi Kumagai
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
| | - Yuki Sato
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
- Department of Biophysics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan
| | - Reza Bagherzadeh
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, Banihashem, Tehran, Iran
- Department of Developmental Biology, University of Science and Culture, Banihashem, Tehran, Iran
| | - Kiyokazu Agata
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
- Department of Biophysics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, Japan
- National Institute for Basic Biology, National Institutes of Natural Science, 38 Nishigonaka, Myodaiji, Okazaki, Japan
| | - Takeshi Inoue
- Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, Japan
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6
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Akiyama Y, Agata K, Inoue T. Coordination between binocular field and spontaneous self-motion specifies the efficiency of planarians' photo-response orientation behavior. Commun Biol 2018; 1:148. [PMID: 30272024 PMCID: PMC6155068 DOI: 10.1038/s42003-018-0151-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 08/27/2018] [Indexed: 11/15/2022] Open
Abstract
Eyes show remarkable diversity in morphology among creatures. However, little is known about how morphological traits of eyes affect behaviors. Here, we investigate the mechanisms responsible for the establishment of efficient photo-response orientation behavior using the planarian Dugesia japonica as a model. Our behavioral assays reveal the functional angle of the visual field and show that the binocular field formed by paired eyes in D. japonica has an impact on the accurate recognition of the direction of a light source. Furthermore, we find that the binocular field in coordination with spontaneous wigwag self-motion of the head specifies the efficiency of photo-responsive evasive behavior in planarians. Our findings suggest that the linkage between the architecture of the sensory organs and spontaneous self-motion is a platform that serves for efficient and adaptive outcomes of planarian and potentially other animal behaviors. Yoshitaro Akiyama et al. report the use of innovative behavioral assays in planarian flatworms to investigate the mechanism by which they efficiently respond to light. They find that binocular vision and spontaneous self-motion are key factors for accurately detecting the direction of a light source.
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Affiliation(s)
- Yoshitaro Akiyama
- Department of Biophysics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502, Japan.,Department of Advanced Interdisciplinary Studies, Graduate School of Engineering, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo, 153-8904, Japan
| | - Kiyokazu Agata
- Department of Biophysics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502, Japan.,Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, 171-8588, Japan
| | - Takeshi Inoue
- Department of Biophysics, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake, Sakyo-ku, Kyoto, 606-8502, Japan. .,Department of Life Science, Faculty of Science, Gakushuin University, 1-5-1 Mejiro, Toshima-ku, Tokyo, 171-8588, Japan.
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7
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Shiroor DA, Bohr TE, Adler CE. Chemical Amputation and Regeneration of the Pharynx in the Planarian Schmidtea mediterranea. J Vis Exp 2018. [PMID: 29630058 DOI: 10.3791/57168] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Planarians are flatworms that are extremely efficient at regeneration. They owe this ability to a large number of stem cells that can rapidly respond to any type of injury. Common injury models in these animals remove large amounts of tissue, which damages multiple organs. To overcome this broad tissue damage, we describe here a method to selectively remove a single organ, the pharynx, in the planarian Schmidtea mediterranea. We achieve this by soaking animals in a solution containing the cytochrome oxidase inhibitor sodium azide. Brief exposure to sodium azide causes extrusion of the pharynx from the animal, which we call "chemical amputation." Chemical amputation removes the entire pharynx, and generates a small wound where the pharynx attaches to the intestine. After extensive rinsing, all amputated animals regenerate a fully functional pharynx in approximately one week. Stem cells in the rest of the body drive regeneration of the new pharynx. Here, we provide a detailed protocol for chemical amputation, and describe both histological and behavioral methods to assess successful amputation and regeneration.
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Affiliation(s)
- Divya A Shiroor
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University
| | - Tisha E Bohr
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University
| | - Carolyn E Adler
- Department of Molecular Medicine, College of Veterinary Medicine, Cornell University;
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8
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An Y, Kawaguchi A, Zhao C, Toyoda A, Sharifi-Zarchi A, Mousavi SA, Bagherzadeh R, Inoue T, Ogino H, Fujiyama A, Chitsaz H, Baharvand H, Agata K. Draft genome of Dugesia japonica provides insights into conserved regulatory elements of the brain restriction gene nou-darake in planarians. ZOOLOGICAL LETTERS 2018; 4:24. [PMID: 30181897 PMCID: PMC6114478 DOI: 10.1186/s40851-018-0102-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2018] [Accepted: 07/03/2018] [Indexed: 05/03/2023]
Abstract
BACKGROUND Planarians are non-parasitic Platyhelminthes (flatworms) famous for their regeneration ability and for having a well-organized brain. Dugesia japonica is a typical planarian species that is widely distributed in the East Asia. Extensive cellular and molecular experimental methods have been developed to identify the functions of thousands of genes in this species, making this planarian a good experimental model for regeneration biology and neurobiology. However, no genome-level information is available for D. japonica, and few gene regulatory networks have been identified thus far. RESULTS To obtain whole-genome information on this species and to study its gene regulatory networks, we extracted genomic DNA from 200 planarians derived from a laboratory-bred asexual clonal strain, and sequenced 476 Gb of data by second-generation sequencing. Kmer frequency graphing and fosmid sequence analysis indicated a complex genome that would be difficult to assemble using second-generation sequencing short reads. To address this challenge, we developed a new assembly strategy and improved the de novo genome assembly, producing a 1.56 Gb genome sequence (DjGenome ver1.0, including 202,925 scaffolds and N50 length 27,741 bp) that covers 99.4% of all 19,543 genes in the assembled transcriptome, although the genome is fragmented as 80% of the genome consists of repeated sequences (genomic frequency ≥ 2). By genome comparison between two planarian genera, we identified conserved non-coding elements (CNEs), which are indicative of gene regulatory elements. Transgenic experiments using Xenopus laevis indicated that one of the CNEs in the Djndk gene may be a regulatory element, suggesting that the regulation of the ndk gene and the brain formation mechanism may be conserved between vertebrates and invertebrates. CONCLUSION This draft genome and CNE analysis will contribute to resolving gene regulatory networks in planarians. The genome database is available at: http://www.planarian.jp.
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Affiliation(s)
- Yang An
- Department of Biophysics, Kyoto University, Kyoto, Japan
- Present address: Immolife-biotech Co., Ltd., Nanjing, China
| | - Akane Kawaguchi
- Department of Animal Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
- Present address: Research Institute of Molecular Pathology (IMP), Vienna, Austria
| | - Chen Zhao
- School of Pharmacy, Fudan University, Shanghai, China
- Present address: Immolife-biotech Co., Ltd., Nanjing, China
- Institute of Neurogenomics, Helmholtz Zentrum München, German Research Centre for Environmental Health, Neuherberg, Germany
| | - Atsushi Toyoda
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Japan
| | - Ali Sharifi-Zarchi
- Department of Computer Science, Colorado State University, Fort Collins, USA
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
- Department of Computer Engineering, Sharif University of Technology, Tehran, Iran
| | - Seyed Ahmad Mousavi
- Department of Computer Science, Colorado State University, Fort Collins, USA
| | - Reza Bagherzadeh
- Department of Biophysics, Kyoto University, Kyoto, Japan
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
- Department of Developmental Biology, University of Science and Culture, Tehran, Iran
- Present address: Department of Life Science, Gakushuin University, Tokyo, Japan
| | - Takeshi Inoue
- Department of Biophysics, Kyoto University, Kyoto, Japan
- Present address: Department of Life Science, Gakushuin University, Tokyo, Japan
| | - Hajime Ogino
- Department of Animal Bioscience, Nagahama Institute of Bio-Science and Technology, Nagahama, Japan
- Present address: Amphibian Research Center, Hiroshima University, Higashi-hiroshima, Japan
| | - Asao Fujiyama
- Comparative Genomics Laboratory, National Institute of Genetics, Mishima, Japan
| | - Hamidreza Chitsaz
- Department of Computer Science, Colorado State University, Fort Collins, USA
| | - Hossein Baharvand
- Department of Stem Cells and Developmental Biology, Cell Science Research Center, Royan Institute for Stem Cell Biology and Technology, ACECR, Tehran, Iran
- Department of Developmental Biology, University of Science and Culture, Tehran, Iran
| | - Kiyokazu Agata
- Department of Biophysics, Kyoto University, Kyoto, Japan
- Present address: Department of Life Science, Gakushuin University, Tokyo, Japan
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9
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Ross KG, Currie KW, Pearson BJ, Zayas RM. Nervous system development and regeneration in freshwater planarians. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2017; 6. [DOI: 10.1002/wdev.266] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 01/10/2017] [Accepted: 01/20/2017] [Indexed: 01/22/2023]
Affiliation(s)
- Kelly G. Ross
- Department of Biology San Diego State University San Diego CA USA
| | - Ko W. Currie
- Program in Developmental and Stem Cell Biology The Hospital for Sick Children Toronto Canada
- Department of Molecular Genetics University of Toronto Toronto Canada
- Ontario Institute for Cancer Research Toronto Canada
| | - Bret J. Pearson
- Program in Developmental and Stem Cell Biology The Hospital for Sick Children Toronto Canada
- Department of Molecular Genetics University of Toronto Toronto Canada
- Ontario Institute for Cancer Research Toronto Canada
| | - Ricardo M. Zayas
- Department of Biology San Diego State University San Diego CA USA
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