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Minařík M, Modrell MS, Gillis JA, Campbell AS, Fuller I, Lyne R, Micklem G, Gela D, Pšenička M, Baker CVH. Identification of multiple transcription factor genes potentially involved in the development of electrosensory versus mechanosensory lateral line organs. Front Cell Dev Biol 2024; 12:1327924. [PMID: 38562141 PMCID: PMC10982350 DOI: 10.3389/fcell.2024.1327924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2023] [Accepted: 02/19/2024] [Indexed: 04/04/2024] Open
Abstract
In electroreceptive jawed vertebrates, embryonic lateral line placodes give rise to electrosensory ampullary organs as well as mechanosensory neuromasts. Previous reports of shared gene expression suggest that conserved mechanisms underlie electroreceptor and mechanosensory hair cell development and that electroreceptors evolved as a transcriptionally related "sister cell type" to hair cells. We previously identified only one transcription factor gene, Neurod4, as ampullary organ-restricted in the developing lateral line system of a chondrostean ray-finned fish, the Mississippi paddlefish (Polyodon spathula). The other 16 transcription factor genes we previously validated in paddlefish were expressed in both ampullary organs and neuromasts. Here, we used our published lateral line organ-enriched gene-set (arising from differential bulk RNA-seq in late-larval paddlefish), together with a candidate gene approach, to identify 25 transcription factor genes expressed in the developing lateral line system of a more experimentally tractable chondrostean, the sterlet (Acipenser ruthenus, a small sturgeon), and/or that of paddlefish. Thirteen are expressed in both ampullary organs and neuromasts, consistent with conservation of molecular mechanisms. Seven are electrosensory-restricted on the head (Irx5, Irx3, Insm1, Sp5, Satb2, Mafa and Rorc), and five are the first-reported mechanosensory-restricted transcription factor genes (Foxg1, Sox8, Isl1, Hmx2 and Rorb). However, as previously reported, Sox8 is expressed in ampullary organs as well as neuromasts in a catshark (Scyliorhinus canicula), suggesting the existence of lineage-specific differences between cartilaginous and ray-finned fishes. Overall, our results support the hypothesis that ampullary organs and neuromasts develop via largely conserved transcriptional mechanisms, and identify multiple transcription factors potentially involved in the formation of electrosensory versus mechanosensory lateral line organs.
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Affiliation(s)
- Martin Minařík
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Melinda S. Modrell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - J. Andrew Gillis
- Department of Zoology, University of Cambridge, Cambridge, United Kingdom
- Josephine Bay Paul Center for Comparative Molecular Biology and Evolution, Marine Biological Laboratory, Woods Hole, MA, United States
| | - Alexander S. Campbell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Isobel Fuller
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Rachel Lyne
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Gos Micklem
- Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - David Gela
- Faculty of Fisheries and Protection of Waters, Research Institute of Fish Culture and Hydrobiology, University of South Bohemia in České Budějovice, Vodňany, Czechia
| | - Martin Pšenička
- Faculty of Fisheries and Protection of Waters, Research Institute of Fish Culture and Hydrobiology, University of South Bohemia in České Budějovice, Vodňany, Czechia
| | - Clare V. H. Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
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2
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Káldy J, Fazekas G, Kovács B, Molnár M, Lázár B, Pálinkás-Bodzsár N, Ljubobratović U, Fazekas G, Kovács G, Várkonyi E. Unidirectional hybridization between American paddlefish Polyodon spathula (Walbaum, 1792) and sterlet Acipenser ruthenus (Linnaeus, 1758). PeerJ 2024; 12:e16717. [PMID: 38259665 PMCID: PMC10802154 DOI: 10.7717/peerj.16717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 12/04/2023] [Indexed: 01/24/2024] Open
Abstract
Interspecific hybridizations among sturgeon species are feasible and often bidirectional. The American paddlefish (Polyodon spathula) from Family Polyodontidae and sturgeon species from Family Acipenseridae were reported capable of hybridization, but viable hybrids have been described only in crosses with the American paddlefish as paternal parents. In the reciprocal cross, the hybrids were not viable however embryos start to develop and reach late gastrula and early neurula stages. The goal of this study was to examine the hybridization between the sterlet sturgeon (Acipenser ruthenus) and the American paddlefish. Hybrid and purebred crosses were produced by artificial fertilization. Viable hybrid offspring were harvested (three month old) and verified in the families produced by female sterlet crossing with male American paddlefish. In the reciprocal hybrid crosses with female American paddlefish and male sterlet, the embryos development did not pass over 120 h post fertilization, indicating the unidirectional hybridization between American paddlefish and sterlet. Chromosome counting showed for the same ploidy level of viable hybrid and parent species. Analysis of three microsatellite markers confirmed the unidirectional hybridization between the American paddlefish and the sterlet species. Overall, the inferred genetic cause suggests that unidirectional hybridization between American paddlefish and sterlet may be the case not only for these two species but likely also between American paddlefish and other sturgeon species.
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Affiliation(s)
- Jenő Káldy
- Research Centre for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Szarvas, Békés, Hungary
| | - Georgina Fazekas
- Research Centre for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Szarvas, Békés, Hungary
- PhD School of Animal Biotechnology and Animal Science, Hungarian University of Agriculture and Life Sciences, Gödöllő, Pest, Hungary
| | - Balázs Kovács
- Department of Molecular Ecology, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Gödöllő, Pest, Hungary
| | - Mariann Molnár
- PhD School of Animal Biotechnology and Animal Science, Hungarian University of Agriculture and Life Sciences, Gödöllő, Pest, Hungary
- National Centre for Biodiversity and Gene Conservation, Institute for Farm Animal Gene Conservation, Gödöllő, Pest, Hungary
| | - Bence Lázár
- National Centre for Biodiversity and Gene Conservation, Institute for Farm Animal Gene Conservation, Gödöllő, Pest, Hungary
- Animal Biotechnology Department, Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Gödöllő, Pest, Hungary
| | - Nóra Pálinkás-Bodzsár
- National Centre for Biodiversity and Gene Conservation, Institute for Farm Animal Gene Conservation, Gödöllő, Pest, Hungary
| | - Uroš Ljubobratović
- Research Centre for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Szarvas, Békés, Hungary
| | - Gyöngyvér Fazekas
- Research Centre for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Szarvas, Békés, Hungary
| | - Gyula Kovács
- Research Centre for Fisheries and Aquaculture, Institute of Aquaculture and Environmental Safety, Hungarian University of Agriculture and Life Sciences, Szarvas, Békés, Hungary
| | - Eszter Várkonyi
- National Centre for Biodiversity and Gene Conservation, Institute for Farm Animal Gene Conservation, Gödöllő, Pest, Hungary
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3
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Stundl J, Pospisilova A, Matějková T, Psenicka M, Bronner ME, Cerny R. Migratory patterns and evolutionary plasticity of cranial neural crest cells in ray-finned fishes. Dev Biol 2020; 467:14-29. [PMID: 32835652 DOI: 10.1016/j.ydbio.2020.08.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 02/07/2023]
Abstract
The cranial neural crest (CNC) arises within the developing central nervous system, but then migrates away from the neural tube in three consecutive streams termed mandibular, hyoid and branchial, respectively, according to the order along the anteroposterior axis. While the process of neural crest emigration generally follows a conserved anterior to posterior sequence across vertebrates, we find that ray-finned fishes (bichir, sterlet, gar, and pike) exhibit several heterochronies in the timing and order of CNC emergence that influences their subsequent migratory patterns. First, emigration of the cranial neural crest in these fishes occurs prematurely compared to other vertebrates, already initiating during early neurulation and well before neural tube closure. Second, delamination of the hyoid stream occurs prior to the more anterior mandibular stream; this is associated with early morphogenesis of key hyoid structures like external gills (bichir), a large opercular flap (gar) or first forming cartilage (pike). In sterlet, the hyoid and branchial CNC cells form a single hyobranchial sheet, which later segregates in concert with second pharyngeal pouch morphogenesis. Taken together, the results show that despite generally conserved migratory patterns, heterochronic alterations in the timing of emigration and pattern of migration of CNC cells accompanies morphological diversity of ray-finned fishes.
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Affiliation(s)
- Jan Stundl
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic; Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA; South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Vodnany, Czech Republic.
| | - Anna Pospisilova
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Tereza Matějková
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic
| | - Martin Psenicka
- South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Vodnany, Czech Republic
| | - Marianne E Bronner
- Division of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA, USA
| | - Robert Cerny
- Department of Zoology, Faculty of Science, Charles University in Prague, Prague, Czech Republic.
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4
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Tsessarsky AA. The Provisional Dermal Folds in the Oral Apparatus of the American Paddlefish Polyodonspathula Walbaum, 1858 (Acipenseriformes, Polyodontidae). DOKLADY BIOLOGICAL SCIENCES : PROCEEDINGS OF THE ACADEMY OF SCIENCES OF THE USSR, BIOLOGICAL SCIENCES SECTIONS 2019; 486:76-78. [PMID: 31317449 DOI: 10.1134/s0012496619030037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 01/31/2018] [Accepted: 01/31/2018] [Indexed: 06/10/2023]
Abstract
The transitory dermal infoldings are described for the first time in front and behind the upper jaw in the larvae and postlarvae of the American paddlefish, Polyodon spathula Walbaum, 1858. In sturgeons these infoldings are necessary for the jaw protraction. In the paddlefishes, they, probably recapitulate the ancestral state. At the same time, the presence of these folds at the larval stages might indicate that the paddlefish larvae possess the protractive jaws. Further developmental studies of the jaw kinematics in Polyodon spathula are needed to test both hypotheses.
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Affiliation(s)
- A A Tsessarsky
- Severtsov Institute of Ecology and Evolution, Russian Academy of Sciences, 119071, Moscow, Russia.
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5
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Lencer ES, McCune AR. An embryonic staging series up to hatching for Cyprinodon variegatus: An emerging fish model for developmental, evolutionary, and ecological research. J Morphol 2018; 279:1559-1578. [PMID: 30368863 DOI: 10.1002/jmor.20870] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2018] [Revised: 06/17/2018] [Accepted: 06/22/2018] [Indexed: 11/08/2022]
Abstract
Using multiple taxa to research development is necessary for making general conclusions about developmental patterns and mechanisms. We present a staging series for Cyprinodon variegatus as a basis for further study of the developmental biology of fishes in the genus Cyprinodon and for comparative work on teleost fishes beyond the standard models. Cyprinodon are small, euryhaline fishes, widely distributed in fresh, brackish, and hypersaline waters of southern and eastern North America. Cyprinodontids are closely related to fundulids, providing a comparative reference point to the embryological model, Fundulus heteroclitus. Ecologists and evolutionary biologists commonly study Cyprinodon, and we have been using Cyprinodon to study skull variation and its genetic basis among closely related species. We divided embryonic development of C. variegatus into 34 morphologically identifiable stages. We reference our staging series to that already defined for a related model species, Oryzias latipes (medaka) that is studied by a large community of researchers. We provide a description of the early chondrogenesis and ossification of skull and caudal fin bones during the latter stages of embryonic development. We show that Cyprinodon are tractable for studying development. Eggs can be obtained easily from breeding pairs and our study provides a staging system to facilitate future developmental studies.
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Affiliation(s)
- Ezra S Lencer
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York
| | - Amy R McCune
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, New York
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6
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Tulenko FJ, Massey JL, Holmquist E, Kigundu G, Thomas S, Smith SME, Mazan S, Davis MC. Fin-fold development in paddlefish and catshark and implications for the evolution of the autopod. Proc Biol Sci 2018; 284:rspb.2016.2780. [PMID: 28539509 DOI: 10.1098/rspb.2016.2780] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2016] [Accepted: 04/24/2017] [Indexed: 01/04/2023] Open
Abstract
The evolutionary origin of the autopod involved a loss of the fin-fold and associated dermal skeleton with a concomitant elaboration of the distal endoskeleton to form a wrist and digits. Developmental studies, primarily from teleosts and amniotes, suggest a model for appendage evolution in which a delay in the AER-to-fin-fold conversion fuelled endoskeletal expansion by prolonging the function of AER-mediated regulatory networks. Here, we characterize aspects of paired fin development in the paddlefish Polyodon spathula (a non-teleost actinopterygian) and catshark Scyliorhinus canicula (chondrichthyan) to explore aspects of this model in a broader phylogenetic context. Our data demonstrate that in basal gnathostomes, the autopod marker HoxA13 co-localizes with the dermoskeleton component And1 to mark the position of the fin-fold, supporting recent work demonstrating a role for HoxA13 in zebrafish fin ray development. Additionally, we show that in paddlefish, the proximal fin and fin-fold mesenchyme share a common mesodermal origin, and that components of the Shh/LIM/Gremlin/Fgf transcriptional network critical to limb bud outgrowth and patterning are expressed in the fin-fold with a profile similar to that of tetrapods. Together these data draw contrast with hypotheses of AER heterochrony and suggest that limb-specific morphologies arose through evolutionary changes in the differentiation outcome of conserved early distal patterning compartments.
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Affiliation(s)
- Frank J Tulenko
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA.,Australian Regenerative Medicine Institute, Monash University, Victoria, 3800, Australia
| | - James L Massey
- Department of Ecology and Evolutionary Biology, University of Colorado Boulder, CO 80309, USA
| | - Elishka Holmquist
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA
| | - Gabriel Kigundu
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA
| | - Sarah Thomas
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA
| | - Susan M E Smith
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA
| | - Sylvie Mazan
- CNRS, Sorbonne Universités, UPMC Univ Paris 06, UMR7232, Observatoire Océanologique, F-66650 Banyuls-sur-Mer, France
| | - Marcus C Davis
- Department of Molecular and Cellular Biology, Kennesaw State University, GA 30144, USA
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7
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Chevrinais M, Sire JY, Cloutier R. Unravelling the ontogeny of a Devonian early gnathostome, the "acanthodian" Triazeugacanthus affinis (eastern Canada). PeerJ 2017; 5:e3969. [PMID: 29094000 PMCID: PMC5661438 DOI: 10.7717/peerj.3969] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2017] [Accepted: 10/08/2017] [Indexed: 12/01/2022] Open
Abstract
The study of vertebrate ontogenies has the potential to inform us of shared developmental patterns and processes among organisms. However, fossilised ontogenies of early vertebrates are extremely rare during the Palaeozoic Era. A growth series of the Late Devonian “acanthodian” Triazeugacanthus affinis, from the Miguasha Fossil-Fish Lagerstätte, is identified as one of the best known early vertebrate fossilised ontogenies given the exceptional preservation, the large size range, and the abundance of specimens. Morphological, morphometric, histological and chemical data are gathered on a growth series of Triazeugacanthus ranging from 4 to 52 mm in total length. The developmental trajectory of this Devonian “acanthodian” is characteristic of fishes showing a direct development with alternating steps and thresholds. Larvae show no squamation but a progressive appearance of cartilaginous neurocranial and vertebral elements, and appendicular elements, whereas juveniles progress in terms of ossification and squamation. The presence of cartilaginous and bony tissues, discriminated on histological and chemical signatures, shows a progressive mineralisation of neurocranial and vertebral elements. Comparison among different body proportions for larvae, juveniles and adults suggest allometric growth in juveniles. Because of the phylogenetic position of “acanthodians”, Triazeugacanthus ontogeny informs us about deep time developmental conditions in gnathostomes.
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Affiliation(s)
- Marion Chevrinais
- Laboratoire de Paléontologie et Biologie évolutive, Université du Québec à Rimouski, Rimouski, Canada
| | - Jean-Yves Sire
- CNRS-UMR 7138-Evolution Paris-Seine IBPS, Université Pierre et Marie Curie, Paris, France
| | - Richard Cloutier
- Laboratoire de Paléontologie et Biologie évolutive, Université du Québec à Rimouski, Rimouski, Canada
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8
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Notch and Fgf signaling during electrosensory versus mechanosensory lateral line organ development in a non-teleost ray-finned fish. Dev Biol 2017; 431:48-58. [PMID: 28818669 PMCID: PMC5650464 DOI: 10.1016/j.ydbio.2017.08.017] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Revised: 06/05/2017] [Accepted: 08/11/2017] [Indexed: 02/07/2023]
Abstract
The lateral line system is a useful model for studying the embryonic and evolutionary diversification of different organs and cell types. In jawed vertebrates, this ancestrally comprises lines of mechanosensory neuromasts over the head and trunk, flanked on the head by fields of electrosensory ampullary organs, all innervated by lateral line neurons in cranial lateral line ganglia. Both types of sense organs, and their afferent neurons, develop from cranial lateral line placodes. Current research primarily focuses on the posterior lateral line primordium in zebrafish, which migrates as a cell collective along the trunk; epithelial rosettes form in the trailing zone and are deposited as a line of neuromasts, within which hair cells and supporting cells differentiate. However, in at least some other teleosts (e.g. catfishes) and all non-teleosts, lines of cranial neuromasts are formed by placodes that elongate to form a sensory ridge, which subsequently fragments, with neuromasts differentiating in a line along the crest of the ridge. Furthermore, in many non-teleost species, electrosensory ampullary organs develop from the flanks of the sensory ridge. It is unknown to what extent the molecular mechanisms underlying neuromast formation from the zebrafish migrating posterior lateral line primordium are conserved with the as-yet unexplored molecular mechanisms underlying neuromast and ampullary organ formation from elongating lateral line placodes. Here, we report experiments in an electroreceptive non-teleost ray-finned fish, the Mississippi paddlefish Polyodon spathula, that suggest a conserved role for Notch signaling in regulating lateral line organ receptor cell number, but potentially divergent roles for the fibroblast growth factor signaling pathway, both between neuromasts and ampullary organs, and between paddlefish and zebrafish. Notch and Fgf pathway genes are expressed during paddlefish lateral line development. Fgf ligand genes are differentially expressed in neuromasts and ampullary organs. DAPT treatment results in irregular organ spacing and supernumerary receptor cells. SU5402 treatment yields fewer neuromasts, but ampullary organs form precociously. SU5402 treatment also results in supernumerary receptor cells.
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9
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Modrell MS, Lyne M, Carr AR, Zakon HH, Buckley D, Campbell AS, Davis MC, Micklem G, Baker CV. Insights into electrosensory organ development, physiology and evolution from a lateral line-enriched transcriptome. eLife 2017; 6. [PMID: 28346141 PMCID: PMC5429088 DOI: 10.7554/elife.24197] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 03/23/2017] [Indexed: 01/22/2023] Open
Abstract
The anamniote lateral line system, comprising mechanosensory neuromasts and electrosensory ampullary organs, is a useful model for investigating the developmental and evolutionary diversification of different organs and cell types. Zebrafish neuromast development is increasingly well understood, but neither zebrafish nor Xenopus is electroreceptive and our molecular understanding of ampullary organ development is rudimentary. We have used RNA-seq to generate a lateral line-enriched gene-set from late-larval paddlefish (Polyodon spathula). Validation of a subset reveals expression in developing ampullary organs of transcription factor genes critical for hair cell development, and genes essential for glutamate release at hair cell ribbon synapses, suggesting close developmental, physiological and evolutionary links between non-teleost electroreceptors and hair cells. We identify an ampullary organ-specific proneural transcription factor, and candidates for the voltage-sensing L-type Cav channel and rectifying Kv channel predicted from skate (cartilaginous fish) ampullary organ electrophysiology. Overall, our results illuminate ampullary organ development, physiology and evolution.
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Affiliation(s)
- Melinda S Modrell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Mike Lyne
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom.,Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Adrian R Carr
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom.,Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Harold H Zakon
- Department of Neuroscience, The University of Texas at Austin, Austin, United States.,Department of Integrative Biology, The University of Texas at Austin, Austin, United States
| | - David Buckley
- Departmento de Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales-MNCN-CSIC, Madrid, Spain.,Department of Natural Sciences, Saint Louis University - Madrid Campus, Madrid, Spain
| | - Alexander S Campbell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - Marcus C Davis
- Department of Molecular and Cellular Biology, Kennesaw State University, Kennesaw, United States
| | - Gos Micklem
- Cambridge Systems Biology Centre, University of Cambridge, Cambridge, United Kingdom.,Department of Genetics, University of Cambridge, Cambridge, United Kingdom
| | - Clare Vh Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
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10
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HoxD expression in the fin-fold compartment of basal gnathostomes and implications for paired appendage evolution. Sci Rep 2016; 6:22720. [PMID: 26940624 PMCID: PMC4778128 DOI: 10.1038/srep22720] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Accepted: 02/18/2016] [Indexed: 11/24/2022] Open
Abstract
The role of Homeobox transcription factors during fin and limb development have been the focus of recent work investigating the evolutionary origin of limb-specific morphologies. Here we characterize the expression of HoxD genes, as well as the cluster-associated genes Evx2 and LNP, in the paddlefish Polyodon spathula, a basal ray-finned fish. Our results demonstrate a collinear pattern of nesting in early fin buds that includes HoxD14, a gene previously thought to be isolated from global Hox regulation. We also show that in both Polyodon and the catshark Scyliorhinus canicula (a representative chondrichthyan) late phase HoxD transcripts are present in cells of the fin-fold and co-localize with And1, a component of the dermal skeleton. These new data support an ancestral role for HoxD genes in patterning the fin-folds of jawed vertebrates, and fuel new hypotheses about the evolution of cluster regulation and the potential downstream differentiation outcomes of distinct HoxD-regulated compartments.
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11
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Smith MM, Johanson Z, Butts T, Ericsson R, Modrell M, Tulenko FJ, Davis MC, Fraser GJ. Making teeth to order: conserved genes reveal an ancient molecular pattern in paddlefish (Actinopterygii). Proc Biol Sci 2015; 282:rspb.2014.2700. [PMID: 25788604 PMCID: PMC4389609 DOI: 10.1098/rspb.2014.2700] [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] [Indexed: 11/30/2022] Open
Abstract
Ray-finned fishes (Actinopterygii) are the dominant vertebrate group today (+30 000 species, predominantly teleosts), with great morphological diversity, including their dentitions. How dental morphological variation evolved is best addressed by considering a range of taxa across actinopterygian phylogeny; here we examine the dentition of Polyodon spathula (American paddlefish), assigned to the basal group Acipenseriformes. Although teeth are present and functional in young individuals of Polyodon, they are completely absent in adults. Our current understanding of developmental genes operating in the dentition is primarily restricted to teleosts; we show that shh and bmp4, as highly conserved epithelial and mesenchymal genes for gnathostome tooth development, are similarly expressed at Polyodon tooth loci, thus extending this conserved developmental pattern within the Actinopterygii. These genes map spatio-temporal tooth initiation in Polyodon larvae and provide new data in both oral and pharyngeal tooth sites. Variation in cellular intensity of shh maps timing of tooth morphogenesis, revealing a second odontogenic wave as alternate sites within tooth rows, a dental pattern also present in more derived actinopterygians. Developmental timing for each tooth field in Polyodon follows a gradient, from rostral to caudal and ventral to dorsal, repeated during subsequent loss of teeth. The transitory Polyodon dentition is modified by cessation of tooth addition and loss. As such, Polyodon represents a basal actinopterygian model for the evolution of developmental novelty: initial conservation, followed by tooth loss, accommodating the adult trophic modification to filter-feeding.
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Affiliation(s)
- Moya M Smith
- Craniofacial Development and Stem Cell Biology, King's College London Dental Institute, London, UK Department of Earth Sciences, Natural History Museum, London, UK
| | - Zerina Johanson
- Department of Earth Sciences, Natural History Museum, London, UK
| | - Thomas Butts
- MRC Centre for Developmental Neurobiology, King's College London, London, UK
| | - Rolf Ericsson
- Department of Earth Sciences, Natural History Museum, London, UK
| | - Melinda Modrell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, UK
| | - Frank J Tulenko
- Department of Biology and Physics, College of Science and Mathematics, Kennesaw State University, Kennesaw, GA, USA
| | - Marcus C Davis
- Department of Biology and Physics, College of Science and Mathematics, Kennesaw State University, Kennesaw, GA, USA
| | - Gareth J Fraser
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
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12
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Butts T, Modrell MS, Baker CVH, Wingate RJT. The evolution of the vertebrate cerebellum: absence of a proliferative external granule layer in a non-teleost ray-finned fish. Evol Dev 2014; 16:92-100. [PMID: 24617988 DOI: 10.1111/ede.12067] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The cerebellum represents one of the most morphologically variable structures in the vertebrate brain. To shed light on its evolutionary history, we have examined the molecular anatomy and proliferation of the developing cerebellum of the North American paddlefish, Polyodon spathula. Absence of an external proliferative cerebellar layer and the restriction of Atonal1 expression to the rhombic lip and valvular primordium demonstrate that transit amplification in a cerebellar external germinal layer, a prominent feature of amniote cerebellum development, is absent in paddlefish. Furthermore, expression of Sonic hedgehog, which drives secondary proliferation in the mouse cerebellum, is absent from the paddlefish cerebellum. These data are consistent with what has been observed in zebrafish and suggest that the transit amplification seen in the amniote cerebellum was either lost very early in the ray-finned fish lineage or evolved in the lobe-finned fish lineage. We also suggest that the Atoh1-positive proliferative valvular primordium may represent a synapomorphy (shared derived character) of ray-finned fishes. The topology of valvular primordium development in paddlefish differs significantly from that of zebrafish and correlates with the adult cerebellar form. The distribution of proliferative granule cell precursors in different vertebrate taxa is thus the likely determining factor in cerebellar morphological diversity.
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Affiliation(s)
- Thomas Butts
- MRC Centre for Developmental Neurobiology, King's College London, London, UK
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13
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Archambeault S, Taylor JA, Crow KD. HoxA and HoxD expression in a variety of vertebrate body plan features reveals an ancient origin for the distal Hox program. EvoDevo 2014; 5:44. [PMID: 25908959 PMCID: PMC4407844 DOI: 10.1186/2041-9139-5-44] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Accepted: 10/01/2014] [Indexed: 12/02/2022] Open
Abstract
Background Hox genes are master regulatory genes that specify positional identities during axial development in animals. Discoveries regarding their concerted expression patterns have commanded intense interest due to their complex regulation and specification of body plan features in jawed vertebrates. For example, the posterior HoxD genes switch to an inverted collinear expression pattern in the mouse autopod where HoxD13 switches from a more restricted to a less restricted domain relative to its neighboring gene on the cluster. We refer to this program as the ‘distal phase’ (DP) expression pattern because it occurs in distal regions of paired fins and limbs, and is regulated independently by elements in the 5′ region upstream of the HoxD cluster. However, few taxa have been evaluated with respect to this pattern, and most studies have focused on pectoral fin morphogenesis, which occurs relatively early in development. Results Here, we demonstrate for the first time that the DP expression pattern occurs with the posterior HoxA genes, and is therefore not solely associated with the HoxD gene cluster. Further, DP Hox expression is not confined to paired fins and limbs, but occurs in a variety of body plan features, including paddlefish barbels - sensory adornments that develop from the first mandibular arch (the former ‘Hox-free zone), and the vent (a medial structure that is analogous to a urethra). We found DP expression of HoxD13 and HoxD12 in the paddlefish barbel; and we present the first evidence for DP expression of the HoxA genes in the hindgut and vent of three ray-finned fishes. The HoxA DP expression pattern is predicted by the recent finding of a shared 5′ regulatory architecture in both the HoxA and HoxD clusters, but has not been previously observed in any body plan feature. Conclusions The Hox DP expression pattern appears to be an ancient module that has been co-opted in a variety of structures adorning the vertebrate bauplan. This module provides a shared genetic program that implies deep homology of a variety of distally elongated structures that has played a significant role in the evolution of morphological diversity in vertebrates Electronic supplementary material The online version of this article (doi:10.1186/2041-9139-5-44) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sophie Archambeault
- Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA
| | - Julia Ann Taylor
- Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA
| | - Karen D Crow
- Department of Biology, San Francisco State University, 1600 Holloway Ave, San Francisco, CA 94132 USA
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Baker CVH, Modrell MS, Gillis JA. The evolution and development of vertebrate lateral line electroreceptors. ACTA ACUST UNITED AC 2014; 216:2515-22. [PMID: 23761476 DOI: 10.1242/jeb.082362] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Electroreception is an ancient vertebrate sense with a fascinating evolutionary history involving multiple losses as well as independent evolution at least twice within teleosts. We review the phylogenetic distribution of electroreception and the morphology and innervation of electroreceptors in different vertebrate groups. We summarise recent work from our laboratory that has confirmed the homology of ampullary electroreceptors in non-teleost jawed vertebrates by showing, in conjunction with previously published work, that these are derived embryonically from lateral line placodes. Finally, we review hypotheses to explain the distribution of electroreception within teleosts, including the hypothesis that teleost ampullary and tuberous electroreceptors evolved via the modification of mechanosensory hair cells in lateral line neuromasts. We conclude that further experimental work on teleost electroreceptor development is needed to test such hypotheses.
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Affiliation(s)
- Clare V H Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge CB2 3DY, UK
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15
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Gillis JA, Modrell MS, Baker CVH. Developmental evidence for serial homology of the vertebrate jaw and gill arch skeleton. Nat Commun 2013; 4:1436. [PMID: 23385581 PMCID: PMC3600657 DOI: 10.1038/ncomms2429] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2012] [Accepted: 01/02/2013] [Indexed: 12/02/2022] Open
Abstract
Gegenbaur’s classical hypothesis of jaw-gill arch serial homology is widely cited, but remains unsupported by either paleontological evidence (e.g. a series of fossils reflecting the stepwise transformation of a gill arch into a jaw) or developmental genetic data (e.g. shared molecular mechanisms underlying segment identity in the mandibular, hyoid and gill arch endoskeletons). Here we show that nested expression of Dlx genes – the “Dlx code” that specifies upper and lower jaw identity in mammals and teleosts – is a primitive feature of the mandibular, hyoid and gill arches of jawed vertebrates. Using fate-mapping techniques, we demonstrate that the principal dorsal and ventral endoskeletal segments of the jaw, hyoid and gill arches of the skate Leucoraja erinacea derive from molecularly equivalent mesenchymal domains of combinatorial Dlx gene expression. Our data suggest that vertebrate jaw, hyoid and gill arch cartilages are serially homologous, and were primitively patterned dorsoventrally by a common Dlx blueprint.
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Affiliation(s)
- J Andrew Gillis
- Department of Physiology, Development and Neuroscience, University of Cambridge, Anatomy Building, Downing Street, Cambridge CB2 3DY, UK.
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16
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Regulation of spermatozoa motility in response to cations in Russian sturgeon Acipenser gueldenstaedtii. Theriogenology 2012; 78:102-9. [DOI: 10.1016/j.theriogenology.2012.01.025] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2011] [Revised: 01/14/2012] [Accepted: 01/19/2012] [Indexed: 11/23/2022]
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Gillis JA, Modrell MS, Baker CVH. A timeline of pharyngeal endoskeletal condensation and differentiation in the shark, Scyliorhinus canicula, and the paddlefish, Polyodon spathula. ZEITSCHRIFT FUR ANGEWANDTE ICHTHYOLOGIE = JOURNAL OF APPLIED ICHTHYOLOGY 2012; 28:341-345. [PMID: 26566297 PMCID: PMC4640176 DOI: 10.1111/j.1439-0426.2012.01976.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The lesser-spotted dogfish (Scyliorhinus canicula) and the North American paddlefish (Polyodon spathula) are two emerging model systems for the study of vertebrate craniofacial development. Notably, both of these taxa have retained plesiomorphic aspects of pharyngeal endoskeletal organization, relative to more commonly used models of vertebrate craniofacial development (e.g. zebrafish, chick and mouse), and are therefore well suited to inform the pharyngeal endoskeletal patterning mechanisms that functioned in the last common ancestor of jawed vertebrates. Here, we present a histological overview of the condensation and chondrogenesis of the most prominent endoskeletal elements of the jaw, hyoid and gill arches - the palatoquadrate/Meckel's cartilage, the hyomandibula/ceratohyal, and the epi-/ceratobranchial cartilages, respectively - in embryonic series of S. canicula and P. spathula. Our observations provide a provisional timeline and anatomical framework for further molecular developmental and functional investigations of pharyngeal endoskeletal differentiation and patterning in these phylogenetically informative taxa.
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Affiliation(s)
- J A Gillis
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - M S Modrell
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
| | - C V H Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, Cambridge, United Kingdom
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18
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Electrosensory ampullary organs are derived from lateral line placodes in bony fishes. Nat Commun 2011; 2:496. [PMID: 21988912 DOI: 10.1038/ncomms1502] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2011] [Accepted: 09/07/2011] [Indexed: 11/09/2022] Open
Abstract
Electroreception is an ancient subdivision of the lateral line sensory system, found in all major vertebrate groups (though lost in frogs, amniotes and most ray-finned fishes). Electroreception is mediated by 'hair cells' in ampullary organs, distributed in fields flanking lines of mechanosensory hair cell-containing neuromasts that detect local water movement. Neuromasts, and afferent neurons for both neuromasts and ampullary organs, develop from lateral line placodes. Although ampullary organs in the axolotl (a representative of the lobe-finned clade of bony fishes) are lateral line placode-derived, non-placodal origins have been proposed for electroreceptors in other taxa. Here we show morphological and molecular data describing lateral line system development in the basal ray-finned fish Polyodon spathula, and present fate-mapping data that conclusively demonstrate a lateral line placode origin for ampullary organs and neuromasts. Together with the axolotl data, this confirms that ampullary organs are ancestrally lateral line placode-derived in bony fishes.
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19
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Modrell MS, Buckley D, Baker CV. Molecular analysis of neurogenic placode development in a basal ray-finned fish. Genesis 2011; 49:278-94. [PMID: 21381180 PMCID: PMC4212515 DOI: 10.1002/dvg.20707] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2010] [Revised: 12/17/2010] [Accepted: 12/20/2010] [Indexed: 11/06/2022]
Abstract
Neurogenic placodes are transient, thickened patches of embryonic vertebrate head ectoderm that give rise to the paired peripheral sense organs and most neurons in cranial sensory ganglia. We present the first analysis of gene expression during neurogenic placode development in a basal actinopterygian (ray-finned fish), the North American paddlefish (Polyodon spathula). Pax3 expression in the profundal placode confirms its homology with the ophthalmic trigeminal placode of amniotes. We report the conservation of expression of Pax2 and Pax8 in the otic and/or epibranchial placodes, Phox2b in epibranchial placode-derived neurons, Sox3 during epibranchial and lateral line placode development, and NeuroD in developing cranial sensory ganglia. We identify Sox3 as a novel marker for developing fields of electrosensory ampullary organs and for ampullary organs themselves. Sox3 is also the first molecular marker for actinopterygian ampullary organs. This is consistent with, though does not prove, a lateral line placode origin for actinopterygian ampullary organs.
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Affiliation(s)
- Melinda S. Modrell
- Department of Physiology, Development and Neuroscience, University of Cambridge, United Kingdom
| | - David Buckley
- Department Biodiversidad y Biología Evolutiva, Museo Nacional de Ciencias Naturales, CSIC, Madrid, Spain
| | - Clare V.H. Baker
- Department of Physiology, Development and Neuroscience, University of Cambridge, United Kingdom
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20
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Zeiske E, Bartsch P, Hansen A. Early ontogeny of the olfactory organ in a basal actinopterygian fish: polypterus. BRAIN, BEHAVIOR AND EVOLUTION 2009; 73:259-72. [PMID: 19590178 DOI: 10.1159/000228162] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2009] [Accepted: 05/17/2009] [Indexed: 11/19/2022]
Abstract
The present study employed light and electron microscopic methods to investigate the ontogenetic origin of the olfactory organ in bichirs (Cladistia: Polypteridae) and explore its evolution among osteichthyans. In former studies we demonstrated that in teleosts a subepidermal layer gives rise to the olfactory placode which in turn builds all types of olfactory cells (basal, receptor, supporting, ciliated non-sensory cells). In contrast, the olfactory placodes in sturgeons (Chondrostei: Acipenseridae) as well as in the clawed frog Xenopus laevis (Anura: Pipidae) originate from two different layers. Receptor neurons derive from cells of the subepidermal (sensory) layer and supporting cells from epidermal cells. As sturgeons and amphibians in some characters show a more primitive condition than teleosts, we extended our study to Polypterus to allow for an approach at the basic osteichthyan pattern. In Polypterus, an internal lumen occurs in early ontogenetic stages surrounded by the epithelium of the olfactory placode. Two different populations of supporting cells follow one another: a primary population derives from the subepidermal layer. Later supporting cells develop from epidermal cells by transdifferentiation. The primary opening of the internal lumen to the exterior develops by invagination from the epidermal surface and simultaneously by a counter-directed process of cell dissociation and fragmentation inside the olfactory placode. Our results indicate the following features to be plesiomorphic actinopterygian character states: The primary olfactory pit (prospective olfactory cavity) is formed by invagination of the epidermal and the subepidermal layer (as in Acipenser and Xenopus). The incurrent and excurrent nostrils derive from a single primary opening which elongates and is then separated by an epidermal bridge into the two external openings (as in Acipenser and many teleosts). The olfactory epithelium derives from an epidermal and a subepidermal layer (as in Acipenser and Xenopus). Apomorphic (derived actinopterygian) features are: (1) an internal lumen as primordium of the future olfactory chamber; (2) a subepidermal layer gives rise to the olfactory epithelium and its constituents (Polypterus and teleosts). As to the origin of the olfactory supporting cells in Polypterus we assume a combination of plesiomorphic and apomorphic characters. We conclude that Acipenser and Xenopus exhibit the most widely distributed features among basal osteognathostomes and thus ancestral character states in the development of the olfactory organs.
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Affiliation(s)
- Eckart Zeiske
- Biozentrum Grindel und Zoologisches Museum der Universitat Hamburg, Hamburg, Germany
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21
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Martin KL, Moravek CL, Flannery JA. Embryonic staging series for the beach spawning, terrestrially incubating California grunion Leuresthes tenuiswith comparisons to other Atherinomorpha. JOURNAL OF FISH BIOLOGY 2009; 75:17-38. [PMID: 20738480 DOI: 10.1111/j.1095-8649.2009.02260.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
California grunion Leuresthes tenuis synchronize spawning with tidal cycles, so the embryos incubate in a terrestrial environment, delay hatching until cued by a specific environmental trigger, and may extend incubation for up to an additional four weeks. These adaptations, however, do not appear to alter the morphology or sequence of early developmental stages as compared to other Atherinomorph fishes in the Orders Beloniformes and Cyprinodontiformes. Embryonic development is described in a series of 30 stages based on morphology observed by light microscopy. Stages are placed in five periods: zygote and cleavage, blastula, gastrula, segmentation and organogenesis, and hatching competence. Embryos from a southern population of L. tenuis in Los Angeles are compared with embryos found > 560 km north in San Francisco Bay. Northern L. tenuis embryos developed more slowly at several stages than southern embryos and reached hatching competence later, but both locations maintained synchrony with the tidal cycle for both spawning and hatching. The variation in rates of development and stage at hatching readiness are forms of developmental heterochrony that may be associated with evolutionary adaptation or morphological plasticity within this highly successful clade.
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Affiliation(s)
- K L Martin
- Department of Biology, Pepperdine University, 24255 Pacific Coast Highway, Malibu, CA 90263-4321, USA.
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22
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Davis MC, Dahn RD, Shubin NH. An autopodial-like pattern of Hox expression in the fins of a basal actinopterygian fish. Nature 2007; 447:473-6. [PMID: 17522683 DOI: 10.1038/nature05838] [Citation(s) in RCA: 97] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2007] [Accepted: 04/13/2007] [Indexed: 11/09/2022]
Abstract
Comparative analyses of Hox gene expression and regulation in teleost fish and tetrapods support the long-entrenched notion that the distal region of tetrapod limbs, containing the wrist, ankle and digits, is an evolutionary novelty. Data from fossils support the notion that the unique features of tetrapod limbs were assembled over evolutionary time in the paired fins of fish. The challenge in linking developmental and palaeontological approaches has been that developmental data for fins and limbs compare only highly derived teleosts and tetrapods; what is lacking are data from extant taxa that retain greater portions of the fin skeletal morphology considered primitive to all bony fish. Here, we report on the expression and function of genes implicated in the origin of the autopod in a basal actinopterygian, Polyodon spathula. Polyodon exhibits a late-phase, inverted collinear expression of 5' HoxD genes, a pattern of expression long considered a developmental hallmark of the autopod and shown in tetrapods to be controlled by a 'digit enhancer' region. These data show that aspects of the development of the autopod are primitive to tetrapods and that the origin of digits entailed the redeployment of ancient patterns of gene activity.
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Affiliation(s)
- Marcus C Davis
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois 60637, USA
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23
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Locomotion in Primitive Fishes. ACTA ACUST UNITED AC 2007. [DOI: 10.1016/s1546-5098(07)26007-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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24
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Dahn RD, Davis MC, Pappano WN, Shubin NH. Sonic hedgehog function in chondrichthyan fins and the evolution of appendage patterning. Nature 2006; 445:311-4. [PMID: 17187056 DOI: 10.1038/nature05436] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Accepted: 11/09/2006] [Indexed: 11/08/2022]
Abstract
The genetic mechanisms regulating tetrapod limb development are well characterized, but how they were assembled during evolution and their function in basal vertebrates is poorly understood. Initial studies report that chondrichthyans, the most primitive extant vertebrates with paired appendages, differ from ray-finned fish and tetrapods in having Sonic hedgehog (Shh)-independent patterning of the appendage skeleton. Here we demonstrate that chondrichthyans share patterns of appendage Shh expression, Shh appendage-specific regulatory DNA, and Shh function with ray-finned fish and tetrapods. These studies demonstrate that some aspects of Shh function are deeply conserved in vertebrate phylogeny, but also highlight how the evolution of Shh regulation may underlie major morphological changes during appendage evolution.
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Affiliation(s)
- Randall D Dahn
- Department of Organismal Biology and Anatomy, The University of Chicago, Chicago, Illinois 60637, USA
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25
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Depew MJ, Simpson CA. 21st century neontology and the comparative development of the vertebrate skull. Dev Dyn 2006; 235:1256-91. [PMID: 16598716 DOI: 10.1002/dvdy.20796] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Classic neontology (comparative embryology and anatomy), through the application of the concept of homology, has demonstrated that the development of the gnathostome (jawed vertebrate) skull is characterized both by a fidelity to the gnathostome bauplan and the exquisite elaboration of final structural design. Just as homology is an old concept amended for modern purposes, so are many of the questions regarding the development of the skull. With due deference to Geoffroy-St. Hilaire, Cuvier, Owen, Lankester et al., we are still asking: How are bauplan fidelity and elaboration of design maintained, coordinated, and modified to generate the amazing diversity seen in cranial morphologies? What establishes and maintains pattern in the skull? Are there universal developmental mechanisms underlying gnathostome autapomorphic structural traits? Can we detect and identify the etiologies of heterotopic (change in the topology of a developmental event), heterochronic (change in the timing of a developmental event), and heterofacient (change in the active capacetence, or the elaboration of capacity, of a developmental event) changes in craniofacial development within and between taxa? To address whether jaws are all made in a like manner (and if not, then how not), one needs a starting point for the sake of comparison. To this end, we present here a "hinge and caps" model that places the articulation, and subsequently the polarity and modularity, of the upper and lower jaws in the context of cranial neural crest competence to respond to positionally located epithelial signals. This model expands on an evolving model of polarity within the mandibular arch and seeks to explain a developmental patterning system that apparently keeps gnathostome jaws in functional registration yet tractable to potential changes in functional demands over time. It relies upon a system for the establishment of positional information where pattern and placement of the "hinge" is driven by factors common to the junction of the maxillary and mandibular branches of the first arch and of the "caps" by the signals emanating from the distal-most first arch midline and the lamboidal junction (where the maxillary branch meets the frontonasal processes). In this particular model, the functional registration of jaws is achieved by the integration of "hinge" and "caps" signaling, with the "caps" sharing at some critical level a developmental history that potentiates their own coordination. We examine the evidential foundation for this model in mice, examine the robustness with which it can be applied to other taxa, and examine potential proximate sources of the signaling centers. Lastly, as developmental biologists have long held that the anterior-most mesendoderm (anterior archenteron roof or prechordal plate) is in some way integral to the normal formation of the head, including the cranial skeletal midlines, we review evidence that the seminal patterning influences on the early anterior ectoderm extend well beyond the neural plate and are just as important to establishing pattern within the cephalic ectoderm, in particular for the "caps" that will yield medial signaling centers known to coordinate jaw development.
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Affiliation(s)
- Michael J Depew
- Department of Craniofacial Development, King's College London, Guy's Hospital, London Bridge, London, United Kingdom.
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26
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Abstract
In Polyodon spathula, the pectoral fin radials, with the exception of the metapterygium, are derived from the decomposition of a single continuous cartilage fin plate that is continuous with the scapulocoracoid. This cartilage sheet develops two interior splits to form three precursor pieces, and these decompose in a predictable way to generate the propterygium and radials. The metapterygium is an extension of the scapulocoracoid that segments off of it during early development. To our knowledge, this has not been reported for acipenserids or other basal actinopterygians. In teleosts, the proximal radials also develop from the "break up" of an initially continuous paddle-like sheet of cartilage along the posterior edge of the scapulocoracoid, and in Polypterus and sharks a similar pattern holds. Thus, the pattern observed in Polyodon may represent the basal developmental condition for the gnathostome pectoral fin. The process underlying development of the superficially similar cartilages of the pelvic and pectoral fins is different. In the pectoral fin, the metapterygium is segmented off of the scapulocoracoid and other radials form from the decomposition of the cartilage plate. In contrast, individual rod-like basipterygial elements form in a close one-to-one correspondence with the middle radials of the pelvic fin, but later fuse to form an anterior element that is branched in appearance. To evaluate further claims of similarity among the pectoral and pelvic fin elements of various fishes, the course of the development of these structures must be observed. The pectoral fin and girdle in Polyodon ossifies in a different sequence than that proposed as ancestral (and highly conserved) for actinopterygians: the supracleithrum ossifies significantly before the cleithrum. The later ossification of the cleithrum in Polyodon may be related to the primary use of the caudal fin vs. the pectoral fins in their locomotion.
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Affiliation(s)
- Paula M Mabee
- Department of Biology, University of South Dakota, Vermillion, South Dakota 57069, USA.
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27
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Lee SH, Bédard O, Buchtová M, Fu K, Richman JM. A new origin for the maxillary jaw. Dev Biol 2005; 276:207-24. [PMID: 15531375 DOI: 10.1016/j.ydbio.2004.08.045] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2004] [Revised: 08/05/2004] [Accepted: 08/31/2004] [Indexed: 10/26/2022]
Abstract
One conserved feature of craniofacial development is that the first pharyngeal arch has two components, the maxillary and mandibular, which then form the upper and lower jaws, respectively. However, until now, there have been no tests of whether the maxillary cells originate entirely within the first pharyngeal arch or whether they originate in a separate condensation, cranial to the first arch. We therefore constructed a fate map of the pharyngeal arches and environs with a series of dye injections into stage 13-17 chicken embryos. We found that from the earliest stage examined, the major contribution to the maxillary bud is from post-optic mesenchyme with a relatively minor contribution from the maxillo-mandibular cleft. Cells labeled within the first pharyngeal arch contributed exclusively to the mandibular prominence. Gene expression data showed that there were different molecular codes for the cranial and caudal maxillary prominence. Two of the genes examined, Rarbeta (retinoic acid receptor beta) and Bmp4 (bone morphogenetic protein) were expressed in the post-optic mesenchyme and epithelium prior to formation of the maxillary prominence and then were restricted to the cranial half of the maxillary prominence. In order to determine the derivatives of the maxillary prominence, we performed focal injections of CM-DiI into the stage 24 maxillary prominence. Labeled cells contributed to the maxillary, palatine, and jugal bones, but not the other elements of the upper beak, the premaxilla and prenasal cartilage. We also determined that the cranial cells give rise to more distal parts of the upper beak, whereas caudal cells form proximal structures. Grafts of stage 24 maxillary prominences were also analyzed to determine skeletal derivatives and these results concurred with the DiI maps. These early and later fate maps indicate that the maxillary prominence and its skeletal derivatives are not derived from the first pharyngeal arch but rather from a separate maxillary condensation that occurs between the eye and the maxillo-mandibular cleft. These data also suggest that during evolution, recession of the first pharyngeal arch-derived palatoquadrate cartilage to a more proximal position gave way to the bony upper jaw of amniotes.
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Affiliation(s)
- Sang-Hwy Lee
- Department of Oral, Maxillofacial Surgery and Oral Science Research Center, Medical Science and Engineering Research Center, BK 21 Project for Medical Science, College of Dentistry Yonsei University, Seoul, Korea
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28
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Zhu M, Ahlberg PE. The origin of the internal nostril of tetrapods. Nature 2004; 432:94-7. [PMID: 15525987 DOI: 10.1038/nature02843] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2004] [Accepted: 07/15/2004] [Indexed: 11/09/2022]
Abstract
The choana, a unique 'internal nostril' opening from the nasal sac into the roof of the mouth, is a key part of the tetrapod (land vertebrate) respiratory system. It was the first component of the tetrapod body plan to evolve, well before the origin of limbs, and is therefore crucial to our understanding of the beginning of the fish-tetrapod transition. However, there is no consensus on the origin of the choana despite decades of heated debate; some have claimed that it represents a palatally displaced external nostril, but others have argued that this is implausible because it implies breaking and rejoining the maxillary-premaxillary dental arcade and the maxillary branch of nerve V. The fossil record has not resolved the dispute, because the choana is fully developed in known tetrapod stem-group members. Here we present new material of Kenichthys, a 395-million-year-old fossil fish from China, that provides direct evidence for the origin of the choana and establishes its homology: it is indeed a displaced posterior external nostril that, during a brief transitional stage illustrated by Kenichthys, separated the maxilla from the premaxilla.
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Affiliation(s)
- Min Zhu
- Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, P.O. Box 643, Beijing 100044, China.
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Davis MC, Shubin NH, Force A. Pectoral fin and girdle development in the basal actinopterygiansPolyodon spathula andAcipenser transmontanus. J Morphol 2004; 262:608-28. [PMID: 15376275 DOI: 10.1002/jmor.10264] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The pectoral fins of Acipenseriformes possess endoskeletons with elements homologous to both the fin radials of teleosts and the limb bones of tetrapods. Here we present a study of pectoral fin development in the North American paddlefish, Polyodon spathula, and the white sturgeon, Acipenser transmontanus, which reveals that aspects of both teleost and tetrapod endoskeletal patterning mechanisms are present in Acipenseriformes. Those elements considered homologous to teleost radials, the propterygium and the mesopterygial radials, form via subdivision of an initially chondrogenic plate of mesenchymal cells called the endoskeletal disc. In Acipenseriformes, elements homologous to the sarcopterygian metapterygium develop separately from the endoskeletal disc as an outgrowth of the endoskeletal shoulder girdle that extends into the posterior margin of the finbud. As in tetrapods, the elongating metapterygium and the metapterygial radials form in a proximal to distal order as discrete condensations from initially nonchondrogenic mesenchyme. Patterns of variation seen in the Acipenseriform fin also correlate with putative homology: all variants from the "normal" fin bauplan involved the metapterygium and the metapterygial radials alone. The primary factor distinguishing Polyodon and Acipenser fin development from each other is the composition of the endoskeletal extracellular matrix. Proteoglycans (visualized with Alcian Blue) and Type II collagen (visualized by immunohistochemistry) are secreted in different places within the mesenchymal anlage of the fin elements and girdle and at different developmental times. Acipenseriform pectoral fins differ from the fins of teleosts in the relative contribution of the endoskeleton and dermal rays. The fins of Polyodon and Acipenser possess elaborate endoskeletons overlapped along their distal margins by dermal lepidotrichia. In contrast, teleost fins generally possess relatively small endoskeletal radials that articulate with the dermal fin skeleton terminally, with little or no proximodistal overlap.
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Affiliation(s)
- Marcus C Davis
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60637, USA.
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Zeiske E, Kasumyan A, Bartsch P, Hansen A. Early development of the olfactory organ in sturgeons of the genus Acipenser: a comparative and electron microscopic study. ANATOMY AND EMBRYOLOGY 2003; 206:357-72. [PMID: 12684762 DOI: 10.1007/s00429-003-0309-6] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 12/30/2002] [Indexed: 10/20/2022]
Abstract
Formation and morphology of the olfactory organ of vertebrates has been intensely studied in some taxa for more than a century. As a functionally important and complex sensory organ, its ontogenetic development has often been a matter of debate on higher-level craniate evolution. However, sufficient knowledge of structure and development of the olfactory organ in the crucial taxa needed for a serious phylogenetic reasoning is generally not available. This study aims at this essential primary data source, the detailed structure, morphogenesis, and character definition of the olfactory organ in more basal clades of jawed vertebrates (Gnathostomata). Sturgeon fishes (Acipenseriformes) as recent basal actinopterygians are expected to provide insight into archaic characters and character combinations in bony fishes. Thus, the development of the olfactory placodes of the sterlet, Acipenser ruthenus, and the Siberian sturgeon, Acipenser baerii, was followed histologically, by semi-thin serial sections, and by scanning and transmission electron microscopy. Except for the timing, virtually no differences were observed between the two species. The olfactory placodes become two-layered early in embryonic development. Both the superficial epidermal and the subepidermal layer can easily be distinguished and their development followed by ultrastructural properties. There are three different types of receptor cells: ciliated, microvillous, and crypt cells. The development of the ciliated and the less abundant microvillous receptor cells from the subepidermal layer of the placode is demonstrated. The non-sensory cells of the differentiated olfactory epithelium, i.e. ciliated non-sensory cells and supporting cells, exclusively derive from the superficial epidermal layer. In this respect, acipenserids clearly demonstrate close resemblance to the morphogenetic process found in the tetrapod Xenopus (Anura). The only other adequately described mode found in the actinopterygian zebrafish ( Danio rerio), is considered a derived character. In this case, all cells of the differentiated olfactory epithelium derive from one placodal cell layer. The mode of formation of the nasal sac and its ventilatory openings found in the acipenserids examined here, represents a widespread and probably a plesiomorphic condition of osteognathostomes. In both species, differentiation of the basic cellular composition of the olfactory epithelium is far advanced at the time of onset of extrinsic feeding.
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Affiliation(s)
- Eckart Zeiske
- Zoologisches Institut und Zoologisches Museum, Universität Hamburg, Martin-Luther-King-Platz 3, 20146, Hamburg, Germany
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Martinez GM, Bolker JA. Embryonic and larval staging of summer flounder (Paralichthys dentatus). J Morphol 2003; 255:162-76. [PMID: 12474264 DOI: 10.1002/jmor.10053] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Early development of flatfishes such as the summer flounder Paralichthys dentatus (Pleuronectiformes) has not been extensively documented, largely because of a dearth of material; however, the recent expansion of flatfish aquaculture has made embryos of P. dentatus readily available for developmental studies. We divide development of P. dentatus embryos and larvae into two main periods, pre- and posthatching, and assign stages within each of those primary divisions. Stages from fertilization to hatching loosely follow the general teleost staging scheme suggested by Shardo ([1995] J Morphol 225:125-167); stages from hatching through metamorphosis are aligned with the series used for Japanese flounder, P. olivaceus (Minami [1982] Nippon Suisan Gakkaishi 48:1581-1588; Fukuhara [1986] Nippon Suisan Gakkaishi 52:81-91). Although length, width, and age may serve as approximate indicators of developmental progression in summer flounder, these characteristics are too variable to form the sole basis of a staging table. Therefore, we define stages by morphological criteria drawn from the development of the jaw apparatus and digestive system, eye migration, and notochord tip flexion. Examination of these morphological features in hatched larvae allows accurate and consistent assessment of developmental stage despite variation in timing and size. The staging scheme for flounder embryonic and larval development presented here should facilitate both experimental and comparative research on summer flounder and other flatfish species.
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Affiliation(s)
- Gabriela M Martinez
- Department of Zoology, University of New Hampshire, Durham, New Hampshire 03824, USA.
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Kemp A. Early development of neural tissues and mesenchyme in the Australian lungfish Neoceratodus forsteri (Osteichthyes: Dipnoi). J Zool (1987) 2000. [DOI: 10.1111/j.1469-7998.2000.tb00780.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Didier DA, LeClair EE, Vanbuskirk DR. Embryonic staging and external features of development of the Chimaeroid fish,Callorhinchus milii (Holocephali, Callorhinchidae). J Morphol 1998; 236:25-47. [DOI: 10.1002/(sici)1097-4687(199804)236:1<25::aid-jmor2>3.0.co;2-n] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bartsch P, Gemballa S, Piotrowski T. The Embryonic and Larval Development ofPolypterus senegalusCuvier, 1829: its Staging with Reference to External and Skeletal Features, Behaviour and Locomotory Habits. ACTA ZOOL-STOCKHOLM 1997. [DOI: 10.1111/j.1463-6395.1997.tb01014.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Miyake T, von Herbing IH, Hall BK. Neural ectoderm, neural crest, and placodes: Contribution of the otic placode to the ectodermal lining of the embryonic opercular cavity in Atlantic cod (Teleostei). J Morphol 1997; 231:231-252. [DOI: 10.1002/(sici)1097-4687(199703)231:3<231::aid-jmor3>3.0.co;2-e] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
In common with the embryos of other anamniotes, young of the Australian lungfish, Neoceratodus forsteri, have ciliated cells in the epidermis. These first appear at stage 28, ˜ 10 days before hatching, and develop progressively to a peak in numbers and in activity at stage 44, just after hatching. After this point, ciliary action in the epidermal cells slowly declines, and cilia disappear completely from the outer surface of the hatchling by stage 52. Cilia are lost earlier from the oral epithelium, between stages 45 and 46, and from the epithelium covering the gills and lining the operculum at stage 51, although they are retained in the nares and in the cavity of the olfactory organ. To assess possible functions for the ciliated epidermis in lungfish hatchlings, the presence of cilia in the epidermis of young N. forsteri is compared with landmarks of development. The ciliated epidermal cells are not associated with movements of the embryo within the egg capsule, nor are they a part of a feeding mechanism. They are not related to oxygen uptake. The ciliated epidermis appears to function as a mechanism for clearing the animal of particles and settling organisms before hatching, when the egg membranes have developed holes, and after hatching, when the young fish is living among the submerged rootlets of trees growing on the river bank or in dense stands of aquatic plants. The function of a ciliated epidermis in N. forsteri hatchlings in relation to microhabitat is discussed. © 1996 Wiley-Liss, Inc.
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Affiliation(s)
- A Kemp
- Department of Anatomical Sciences, University of Queensland, St. Lucia, Queensland 4072, Australia
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Shardo JD. Comparative embryology of teleostean fishes. I. Development and staging of the american shad,Alosa sapidissima (Wilson, 1811). J Morphol 1995; 225:125-167. [DOI: 10.1002/jmor.1052250202] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Bolker JA. Gastrulation and mesoderm morphogenesis in the white sturgeon. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 1993; 266:116-31. [PMID: 8501436 DOI: 10.1002/jez.1402660206] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
This study presents a detailed description of gastrulation in the white sturgeon, Acipenser transmontanus, using scanning electron microscopy, histology, and time-lapse filming and video microscopy. This morphological analysis describes the similarity of gastrula structure in the sturgeon and the amphibian Xenopus laevis, and suggests that the species share many developmental mechanisms. It also identifies important differences, such as the equatorial dorsal lip in sturgeon, and provides a basis for interpreting experiments that test the effect of these differences on gastrulation. The onset of gastrulation in the sturgeon is marked by the appearance of a blastoporal equatorial pigment line that forms as the apices of bottle cells contract and concentrate surface pigment granules. Bottle cell formation at the blastopore lip and involution of surface material through the blastopore are strikingly similar to the equivalent processes in amphibian embryos. As gastrulation continues, a distinct cleft of Brachet forms between pre-involution and post-involution material. Following involution, the prospective axial mesoderm located on the dorsal surface of the late blastula (Ballard and Ginsburg: J. Exp. Zool., 213:69-103, 1980) ingresses from a central zone in the posterior archenteron roof surface in a process that is unlike any in Xenopus, but resembles events in other amphibians (Purcell, 1992; Smith: Dev. Biol., 98:250-254, 1983; King: Biol. Bull., 4:287-300, 1903). The detailed comparison of similarities and differences in gastrulation in different vertebrate lineages yields insights into the function and versatility of common developmental mechanisms.
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Affiliation(s)
- J A Bolker
- Department of Molecular and Cell Biology, University of California, Berkeley 94720
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