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Wawrzyniak MK, Matas Serrato LA, Blanchoud S. Artificial seawater based long-term culture of colonial ascidians. Dev Biol 2021; 480:91-104. [PMID: 34418426 DOI: 10.1016/j.ydbio.2021.08.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Revised: 08/03/2021] [Accepted: 08/11/2021] [Indexed: 11/15/2022]
Abstract
Tunicates are highly diverse marine invertebrate filter-feeders that are vertebrates' closest relatives. These organisms, despite a drastically different body plan during their adulthood, have a tissue complexity related to that of vertebrates. Ascidians, which compose most of the Tunicata, are benthic sessile hermaphrodites that reproduce sexually through a motile tadpole larval stage. Over half of the known ascidians species are able to reproduce asexually by budding, typically leading to the formation of colonies where animals, called zooids, are interconnected through an external vascular system. In addition, colonial ascidians are established models for important biological processes including allorecognition, immunobiology, aging, angiogenesis and whole-body regeneration. However, the current paucity in breeding infrastructures limits the study of these animals to coastal regions. To promote a wider scientific spreading and popularity of colonial ascidians, we have developed a flexible recirculating husbandry setup for their long-term in-lab culture. Our system is inspired both by the flow-through aquariums used by coastal ascidian labs, as well as by the recirculating in-lab systems used for zebrafish research. Our hybrid system thus combines colony breeding, water filtering and food culturing in a semi-automated system where specimens develop on hanging microscopy glass slides. Temperature, light/dark cycles, flow speed and feeding rates can be controlled independently in four different breeding environments to provide room for species-specific optimization as well as for running experiments. This setup is complemented with a quarantine for the acclimatization of wild isolates. Herein we present our success in breeding Botrylloides diegensis, a species of colonial ascidians, for more than 3 years in recirculating artificial seawater over 600 km away from their natural habitat. We show that colonies adapt well to in-lab culturing provided that a suitable marine microbiome is present, and that a specific strain can be isolated, propagated and efficiently used for research over prolonged periods of time. The flexible and modular structure of our system can be scaled and adapted to the needs of specific species, such as Botryllus schlosseri, as well as of particular laboratory spaces. Overall, we show that Botrylloides diegensis can be proficiently bred in-land and suggest that our results can be extended to other species of colonial ascidians to promote research on these fascinating animals.
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Affiliation(s)
- Marta K Wawrzyniak
- Department of Biology, University of Fribourg, Chemin Du Musée 10, 1700, Fribourg, Switzerland
| | | | - Simon Blanchoud
- Department of Biology, University of Fribourg, Chemin Du Musée 10, 1700, Fribourg, Switzerland.
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Hudson C, Yasuo H. Neuromesodermal Lineage Contribution to CNS Development in Invertebrate and Vertebrate Chordates. Genes (Basel) 2021; 12:genes12040592. [PMID: 33920662 PMCID: PMC8073528 DOI: 10.3390/genes12040592] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 04/12/2021] [Accepted: 04/13/2021] [Indexed: 12/12/2022] Open
Abstract
Ascidians are invertebrate chordates and the closest living relative to vertebrates. In ascidian embryos a large part of the central nervous system arises from cells associated with mesoderm rather than ectoderm lineages. This seems at odds with the traditional view of vertebrate nervous system development which was thought to be induced from ectoderm cells, initially with anterior character and later transformed by posteriorizing signals, to generate the entire anterior-posterior axis of the central nervous system. Recent advances in vertebrate developmental biology, however, show that much of the posterior central nervous system, or spinal cord, in fact arises from cells that share a common origin with mesoderm. This indicates a conserved role for bi-potential neuromesoderm precursors in chordate CNS formation. However, the boundary between neural tissue arising from these distinct neural lineages does not appear to be fixed, which leads to the notion that anterior-posterior patterning and neural fate formation can evolve independently.
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Yang L, Zhang X, Liu C, Zhang J, Dong B. MiR-92 Family Members Form a Cluster Required for Notochord Tubulogenesis in Urochordate Ciona savignyi. Genes (Basel) 2021; 12:genes12030406. [PMID: 33809016 PMCID: PMC8001136 DOI: 10.3390/genes12030406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/08/2021] [Accepted: 03/09/2021] [Indexed: 11/28/2022] Open
Abstract
MicroRNAs are frequently clustered in the genome and polycistronically transcribed, regulating targeted genes in diverse signaling pathways. The miR-17-92 cluster is a typical miRNA cluster, playing crucial roles in the organogenesis and homeostasis of physiological processes in vertebrates. Here, we identified three miRNAs (csa-miR-92a, csa-miR-92b, and csa-miR-92c) that belonged to the miR-92 family and formed a miRNA cluster in the genome of a urochordate marine ascidian Ciona savignyi. Except for miR-92a and miR-92b, other homologs of the vertebrate miR-17-92 cluster members could not be identified in the Ciona genome. We further found that the mature sequences of urochordate miR-92 family members were highly conserved compared with the vertebrate species. The expression pattern revealed that three miR-92 family members had consistent expression levels in adult tissues and were predominantly expressed in heart and muscle tissue. We further showed that, at the embryonic and larval stages, csa-miR-92c was expressed in the notochord of embryos during 18–31 h post fertilization (hpf) by in situ hybridization. Knockout of csa-miR-92c resulted in the disorganization of notochord cells and the block of lumen coalescence in the notochord. Fibroblast growth factor (FGF), mitogen-activated protein kinase (MAPK), and wingless/integrated (Wnt)/planar cell polarity (PCP) signaling pathways might be involved in the regulatory processes, since a large number of core genes of these pathways were the predicted target genes of the miR-92 family. Taken together, we identified a miR-92 cluster in urochordate Ciona and revealed the expression patterns and the regulatory roles of its members in organogenesis. Our results provide expression and phylogenetic data on the understanding of the miR-92 miRNA cluster’s function during evolution.
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Affiliation(s)
- Libo Yang
- Sars-Fang Centre, MoE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (L.Y.); (X.Z.); (J.Z.)
| | - Xiaoming Zhang
- Sars-Fang Centre, MoE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (L.Y.); (X.Z.); (J.Z.)
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
| | - Chengzhang Liu
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, China;
| | - Jin Zhang
- Sars-Fang Centre, MoE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (L.Y.); (X.Z.); (J.Z.)
| | - Bo Dong
- Sars-Fang Centre, MoE Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao 266003, China; (L.Y.); (X.Z.); (J.Z.)
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China
- Institute of Evolution and Marine Biodiversity, Ocean University of China, Qingdao 266003, China
- Correspondence: ; Tel.: +86-532-82032732
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Abstract
Fourteen aromatic metabolites (6-19) were isolated from an aqueous extract of the solitary tunicate Cnemidocarpa irene collected in Hokkaido, Japan. The structures of the metabolites were determined based on the spectroscopic interpretations, including one- and two-dimensional NMR, mass spectra, UV, and circular dichroism data. The biopterin analogue 10 modulated the behavior of mice after intracerebroventricular injection and showed a weak affinity to ionotropic glutamate receptor subtypes. Analyses of fluorescent coelomic fluid of the tunicate revealed that pterin 12 was responsible for the fluorescence of the blood cells, while β-carbolines 1 and 3 were fluorescent compounds in the serum. The metabolic profiles in adults, juveniles, larvae, and eggs of the animal differed substantially, suggesting that the metabolism of the animal, especially biosynthesis of aromatic secondary metabolites, changes over different life stages.
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Affiliation(s)
- Kei Miyako
- Faculty and Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate, Hokkaido 041-8611, Japan
| | - Yoko Yasuno
- Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi, Osaka 558-8585, Japan
| | - Tetsuro Shinada
- Graduate School of Science, Osaka City University, 3-3-138, Sugimoto, Sumiyoshi, Osaka 558-8585, Japan
| | - Masaki J Fujita
- Faculty and Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate, Hokkaido 041-8611, Japan
| | - Ryuichi Sakai
- Faculty and Graduate School of Fisheries Sciences, Hokkaido University, 3-1-1 Minato-cho, Hakodate, Hokkaido 041-8611, Japan
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Hotta K, Dauga D, Manni L. The ontology of the anatomy and development of the solitary ascidian Ciona: the swimming larva and its metamorphosis. Sci Rep 2020; 10:17916. [PMID: 33087765 PMCID: PMC7578030 DOI: 10.1038/s41598-020-73544-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Accepted: 09/14/2020] [Indexed: 02/07/2023] Open
Abstract
Ciona robusta (Ciona intestinalis type A), a model organism for biological studies, belongs to ascidians, the main class of tunicates, which are the closest relatives of vertebrates. In Ciona, a project on the ontology of both development and anatomy is ongoing for several years. Its goal is to standardize a resource relating each anatomical structure to developmental stages. Today, the ontology is codified until the hatching larva stage. Here, we present its extension throughout the swimming larva stages, the metamorphosis, until the juvenile stages. For standardizing the developmental ontology, we acquired different time-lapse movies, confocal microscope images and histological serial section images for each developmental event from the hatching larva stage (17.5 h post fertilization) to the juvenile stage (7 days post fertilization). Combining these data, we defined 12 new distinct developmental stages (from Stage 26 to Stage 37), in addition to the previously defined 26 stages, referred to embryonic development. The new stages were grouped into four Periods named: Adhesion, Tail Absorption, Body Axis Rotation, and Juvenile. To build the anatomical ontology, 203 anatomical entities were identified, defined according to the literature, and annotated, taking advantage from the high resolution and the complementary information obtained from confocal microscopy and histology. The ontology describes the anatomical entities in hierarchical levels, from the cell level (cell lineage) to the tissue/organ level. Comparing the number of entities during development, we found two rounds on entity increase: in addition to the one occurring after fertilization, there is a second one during the Body Axis Rotation Period, when juvenile structures appear. Vice versa, one-third of anatomical entities associated with the embryo/larval life were significantly reduced at the beginning of metamorphosis. Data was finally integrated within the web-based resource "TunicAnatO", which includes a number of anatomical images and a dictionary with synonyms. This ontology will allow the standardization of data underpinning an accurate annotation of gene expression and the comprehension of mechanisms of differentiation. It will help in understanding the emergence of elaborated structures during both embryogenesis and metamorphosis, shedding light on tissue degeneration and differentiation occurring at metamorphosis.
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Affiliation(s)
- Kohji Hotta
- Department of Biosciences and Informatics, Faculty of Science and Technology, Keio University, Kouhoku-ku, Yokohama, 223-8522, Japan.
| | - Delphine Dauga
- Bioself Communication, 28 rue de la bibliotheque, 13001, Marseille, France
| | - Lucia Manni
- Department of Biology, University of Padova, Via Ugo Bassi 58/B, 35121, Padova, Italy.
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Paffenhöfer GA, Köster M. The Effects of Microplastics on Dolioletta gegenbauri (Tunicata, Thaliacea). Arch Environ Contam Toxicol 2020; 78:94-105. [PMID: 31646360 DOI: 10.1007/s00244-019-00676-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2019] [Accepted: 10/03/2019] [Indexed: 06/10/2023]
Abstract
Oceanographic studies revealed the abundance of minute plastic particles in coastal regions. Such particles, called microplastics, are abundant in sizes smaller than 100 µm ESD (Equivalent Spherical Diameter) and can be collected and ingested by planktonic copepods. Those animals are the most abundant metazoans on our planet. Abundantly co-occurring with planktonic copepods in subtropical and temperate neritic waters are doliolids (Tunicata, Thaliacea), which can dominate subtropical shelves because of their high asexual reproductive performance. Our studies were designed to examine the effects of polystyrene beads at low abundance, compared with phytoplankton, on abundantly occurring gonozooids of Dolioletta gegenbauri. Our findings reveal that such abundance of microplastic particles, in the presence of environmental concentrations of phytoplankton, reduces rates of feeding, growth, and oxygen consumption of this tunicate. Feeding rates on phytoplankton in the presence of beads were reduced by up to 58%, growth rates by up to 85%, and oxygen consumption rates by up to 33%. We conclude that such microplastic particles could limit the often in situ encountered pronounced proliferation of this tunicate species (Deibel in: Bone (ed) The biology of pelagic tunicates, Oxford University Press, Oxford, 1998).
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Affiliation(s)
- Gustav-Adolf Paffenhöfer
- Skidaway Institute of Oceanography, University of Georgia, 10 Ocean Science Circle, Savannah, GA, 31411, USA.
| | - Marion Köster
- Institut für Mikrobiologie, Abteilung Mikrobielle Ökologie, Universität Greifswald, Felix-Hausdorff-Strasse 1, 17487, Greifswald, Germany
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Oricchio FT, Marques AC, Hajdu E, Pitombo FB, Azevedo F, Passos FD, Vieira LM, Stampar SN, Rocha RM, Dias GM. Exotic species dominate marinas between the two most populated regions in the southwestern Atlantic Ocean. Mar Pollut Bull 2019; 146:884-892. [PMID: 31426232 DOI: 10.1016/j.marpolbul.2019.07.013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 07/05/2019] [Accepted: 07/06/2019] [Indexed: 06/10/2023]
Abstract
Human occupation of coastal areas promotes the establishment of non-native species but information on bioinvasions is usually biased toward the Northern Hemisphere. We assessed non-native species' importance in sessile communities at six marinas along the most urbanized area of the Southwestern Atlantic coastline. We found 67 species, of which 19 are exotic. The most frequent species was the exotic polychaete Branchiomma luctuosum, while the most abundant was the exotic bryozoan Schizoporella errata that monopolized the substrata in three marinas. Along with S. errata, the exotic polychaete Hydroides elegans and ascidian Styela plicata dominated space in the three remaining marinas, while native species were in general rare. We show that communities associated with artificial substrata along this Brazilian urbanized area are dominated by exotic species and that using abundance data along with species identity can improve our understanding of the importance of exotic species for the dynamics of biological communities.
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Affiliation(s)
- Felipe T Oricchio
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC (UFABC), Rua Arcturus, 03 - Jardim Antares, 09606-070 São Bernardo do Campo, SP, Brazil.
| | - Antonio C Marques
- Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, R. Matão, Trav. 14, 05508-090 São Paulo, SP, Brazil
| | - Eduardo Hajdu
- Museu Nacional, Universidade Federal do Rio de Janeiro (UFRJ), Quinta da Boa Vista, s/n - São Cristóvão, 20940-040 Rio de Janeiro, RJ, Brazil
| | - Fabio B Pitombo
- Departamento de Biologia Marinha, Universidade Federal Fluminense, 24001-970 Niterói, RJ, Brazil
| | - Fernanda Azevedo
- Universidade Federal do Rio de Janeiro, Instituto de Biologia, Departamento de Zoologia, Av. Carlos Chagas Filho, 373, 21941-902 Rio de Janeiro, RJ, Brazil
| | - Flávio D Passos
- Departamento de Biologia Animal, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6109, 13083-970 Campinas, SP, Brazil
| | - Leandro M Vieira
- Laboratório de Estudos de Bryozoa - LAEBry, Departamento de Zoologia, Centro de Biociências, Universidade Federal de Pernambuco (UFPE), Av. Prof. Moraes Rego 1235 - Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Sergio N Stampar
- Laboratório de Evolução e Diversidade Aquática - LEDA, Departamento de Ciências Biológicas, Universidade Estadual Paulista (UNESP), FCL/Assis, Av. Dom Antônio, 2100, 19806-900 Assis, SP, Brazil
| | - Rosana M Rocha
- Departamento de Zoologia, Universidade Federal do Paraná, 81531-980 Curitiba, PR, Brazil
| | - Gustavo M Dias
- Centro de Ciências Naturais e Humanas, Universidade Federal do ABC (UFABC), Rua Arcturus, 03 - Jardim Antares, 09606-070 São Bernardo do Campo, SP, Brazil
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Pica D, Bloecher N, Dell'Anno A, Bellucci A, Pinto T, Pola L, Puce S. Dynamics of a biofouling community in finfish aquaculture: a case study from the South Adriatic Sea. Biofouling 2019; 35:696-709. [PMID: 31441321 DOI: 10.1080/08927014.2019.1652817] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 06/10/2023]
Abstract
Biofouling is one of the challenges that can strongly affect the finfish farm economy. Although several studies on biofouling in aquaculture have been conducted in the Mediterranean Sea, they focused on specific taxa or were limited to a particular period of sampling. The present study investigated for the first time the development, composition and variation in a biofouling community in a finfish farm with immersion time, season and depth. The results indicate that all these factors influence biofouling succession and recruitment. Moreover, the species that had a crucial role in structuring the community and in the farm cleaning activities were the ascidian Styela plicata and the bivalve Mytilus galloprovincialis. Compared with the literature data, the results highlight the heterogeneity in the composition of the biofouling present in the Mediterranean Sea. Moreover, such knowledge of the biofouling community could provide important information about management efforts and the costs that farmers will face when siting new fish farms.
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Affiliation(s)
- Daniela Pica
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
| | | | - Antonio Dell'Anno
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
| | - Alessandra Bellucci
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
| | - Tommaso Pinto
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
| | - Lisa Pola
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
| | - Stefania Puce
- Dipartimento di Scienze della Vita e dell'Ambiente, Università Politecnica delle Marche, Ancona, Italy
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Tebbett SB, Streit RP, Bellwood DR. Expansion of a colonial ascidian following consecutive mass coral bleaching at Lizard Island, Australia. Mar Environ Res 2019; 144:125-129. [PMID: 30665767 DOI: 10.1016/j.marenvres.2019.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/07/2019] [Accepted: 01/13/2019] [Indexed: 06/09/2023]
Abstract
Mass coral bleaching is challenging today's coral reefs. However, our understanding of dynamics in benthic space holders, following such disturbances, is limited. To address this, we quantified successional dynamics of the ascidian, Didemnum cf. molle using a series of temporally and spatially matched photoquadrats across both the 2016 and 2017 mass coral bleaching events on the Great Barrier Reef. Unlike corals, D. cf. molle appeared to flourish in the warm temperatures and rapidly expanded. Indeed, colony density increased nearly 6-fold over two years with one quadrat experiencing an increase of over 1000 ind. m-2. However, this increase did not simply track the increase in space due to coral mortality, but may have benefitted from reduced predation or increased nutrient availability following mass coral mortality. This study highlights the potential for D. cf molle to expand under bleaching conditions and to become a more prominent component of future reef configurations.
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Affiliation(s)
- Sterling B Tebbett
- ARC Centre of Excellence for Coral Reef Studies, and College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia.
| | - Robert P Streit
- ARC Centre of Excellence for Coral Reef Studies, and College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
| | - David R Bellwood
- ARC Centre of Excellence for Coral Reef Studies, and College of Science and Engineering, James Cook University, Townsville, Queensland, 4811, Australia
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Davis AR, Becerro M, Turon X. Living on the edge: Early life history phases as determinants of distribution in Pyura praeputialis (Heller, 1878), a rocky shore ecosystem engineer. Mar Environ Res 2018; 142:40-47. [PMID: 30269896 DOI: 10.1016/j.marenvres.2018.09.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 06/08/2023]
Abstract
The distribution of intertidal organisms can depend on processes operating early in their life history. The ascidian Pyura praeputialis, a mid- to low-intertidal habitat-forming ecosystem engineer, was strongly associated with specific types of habitat (biogenic vs. bare rock). We examined field patterns and performed laboratory and field experiments to assess the nature of this association. Recruits were frequently found on the tunics of conspecifics and clumps of turfing coralline algae. Larvae preferred these same habitats in a series of laboratory settlement assays. Laboratory-reared juveniles (20- & 50-days-old) survived poorly on bare rock in the laboratory, while those on rugose surfaces - the tunic of adults and turfing corallines - showed high survivorship. Field-collected juveniles (<2 cm) affixed to these rugose habitats also exhibited high survivorship in the field. We conclude that both pre and post-settlement processes determine spatial pattern in this important habitat-forming taxon. The acute sensitivity of juveniles to desiccating conditions was unexpected in an intertidal organism.
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Affiliation(s)
- Andrew R Davis
- Centre for Sustainable Ecosystem Solutions, School of Biological Sciences, University of Wollongong, NSW, 2522, Australia.
| | - Mikel Becerro
- Centre for Advanced Studies of Blanes (CEAB, CSIC), Blanes, Girona, Spain.
| | - Xavier Turon
- Centre for Advanced Studies of Blanes (CEAB, CSIC), Blanes, Girona, Spain.
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Barbosa DB, Mello ADA, Allodi S, de Barros CM. Acute exposure to water-soluble fractions of marine diesel oil: Evaluation of apoptosis and oxidative stress in an ascidian. Chemosphere 2018; 211:308-315. [PMID: 30077111 DOI: 10.1016/j.chemosphere.2018.07.138] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Revised: 07/12/2018] [Accepted: 07/23/2018] [Indexed: 06/08/2023]
Abstract
To understand the mechanisms involved in organisms' responses to toxicity from oil pollution, we studied the effect of acute exposure (24 h) to the marine water-soluble fraction of diesel oil (WFDO) on the ascidian Styela plicata. We evaluated the mortality and behavior by means of the siphon reflex, and the response of blood cells (hemocytes) contained in the pharynx, by means of the production of nitric oxide (NO) and reactive oxygen species (ROS), in addition to the activity of the antioxidant enzyme catalase (CAT). We also correlated oxidative stress with the activation of apoptotic pathways. No mortality occurred 24 h after the ascidians were exposed to 5% and 10% marine WFDO; however, the siphon reflex, a behavioral test based on the time that the animals took to close their siphons, increased. We also observed an inflammatory response, as estimated by the increase in the number of hemocytes in the pharynx. NO and ROS production and CAT activity were reduced, whereas caspase-3, a signaling molecule involved in apoptosis, was activated. This suggests that in ascidians acutely exposed to oil, another mechanism can occur in addition to oxidative stress. Another possibility is that WFDO may directly interact with cellular macromolecules and activate caspase-3, independently of generating oxidative stress. The results showed that components of diesel oil affected a marine organism, which showed reduced ROS production in the pharynx cells, including hemocytes, and activation of apoptotic pathways.
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Affiliation(s)
- Danilo Barreto Barbosa
- Laboratório Integrado de Morfologia, Núcleo em Ecologia e Desenvolvimento Sócio Ambiental de Macaé, NUPEM, Universidade Federal do Rio de Janeiro, Campus UFRJ, Macaé, RJ, Brazil; Programa de Pós-graduação em Ciências Ambientais e Conservação, NUPEM, UFRJ, Macaé, RJ, Brazil
| | - Andressa de Abreu Mello
- Laboratório Integrado de Morfologia, Núcleo em Ecologia e Desenvolvimento Sócio Ambiental de Macaé, NUPEM, Universidade Federal do Rio de Janeiro, Campus UFRJ, Macaé, RJ, Brazil; Laboratório de Neurobiologia Comparativa e do Desenvolvimento, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, RJ, Brazil; Programa de Pós-graduação em Ciências Biológicas, Biofísica, UFRJ, Rio de Janeiro, RJ, Brazil
| | - Silvana Allodi
- Laboratório de Neurobiologia Comparativa e do Desenvolvimento, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, UFRJ, Rio de Janeiro, RJ, Brazil; Programa de Pós-graduação em Ciências Biológicas, Biofísica, UFRJ, Rio de Janeiro, RJ, Brazil
| | - Cintia Monteiro de Barros
- Laboratório Integrado de Morfologia, Núcleo em Ecologia e Desenvolvimento Sócio Ambiental de Macaé, NUPEM, Universidade Federal do Rio de Janeiro, Campus UFRJ, Macaé, RJ, Brazil; Programa de Pós-graduação em Ciências Ambientais e Conservação, NUPEM, UFRJ, Macaé, RJ, Brazil.
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Fletcher LM, Atalah J, Forrest BM. Effect of substrate deployment timing and reproductive strategy on patterns in invasiveness of the colonial ascidian Didemnum vexillum. Mar Environ Res 2018; 141:109-118. [PMID: 30119919 DOI: 10.1016/j.marenvres.2018.08.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 08/06/2018] [Accepted: 08/06/2018] [Indexed: 06/08/2023]
Abstract
The colonial ascidian Didemnum vexillum is a high-profile marine invader, with a geographically widespread distribution after introductions to several temperate regions. D. vexillum has been the focus of several eradication and control programmes globally and the need for specific biological knowledge that relates to establishment processes, persistence, impacts and potential for spread remains. The present study describes temporal patterns of D. vexillum percent cover on experimental substrates over 1.5-years in relation to seasonality of substratum availability, in conjunction with key physical (i.e. temperature and sedimentation) and biological factors (i.e. interspecific competition) at two sites in New Zealand. Colonies showed large fluctuations in percent cover between the two study sites and with reference to timing of bare substratum availability. Colonies generally exhibited an initial lag phase, with peak levels of D. vexillum cover reached during the second summer or autumn post-deployment. The long-term competitive dominance of colonies founded from the reattachment of fragments, as opposed to ambient larval recruitment alone, was also investigated. Increases in colony size as a result of ambient recruitment alone were initially much slower. However, after 12-months colony cover exceeded that of plates inoculated with fragments, suggesting the benefit of the apparent competitive dominance conferred by fragment inoculation is restricted to the early establishment phase. This information will provide increased understanding of the population dynamics of this species, as well as assist in the implementation of effective management strategies through knowledge of environmental drivers of prolific infestations.
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Affiliation(s)
| | - Javier Atalah
- Cawthron Institute, Private Bag 2, Nelson, 7010, New Zealand.
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Zhang X, Liu X, Liu C, Wei J, Yu H, Dong B. Identification and characterization of microRNAs involved in ascidian larval metamorphosis. BMC Genomics 2018; 19:168. [PMID: 29490613 PMCID: PMC5831862 DOI: 10.1186/s12864-018-4566-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2017] [Accepted: 02/22/2018] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Metamorphosis takes place within the life cycle of most marine invertebrates. The marine ascidian is a classical model to study complex cellular processes and underlying molecular mechanisms involved in its larval metamorphosis. The detailed molecular signaling pathways remain elusive, though extracellular signal-regulated kinases (ERKs) and c-Jun N-terminal kinase (JNK) have been revealed to regulate cell migration, differentiation, and apoptosis in ascidian larval organ regression and juvenile organ development. MicroRNAs (miRNAs) are small non-coding RNAs that modulate gene expression at the post-transcriptional level. Large numbers of miRNAs have been demonstrated to be involved in many developmental and metamorphic processes. However, the identification of miRNAs in ascidian larval metamorphosis has not yet been investigated. RESULTS Totally, 106 known and 59 novel miRNAs were screened out through RNA-sequencing of three small RNA libraries from 18 to 21-h post-fertilization (hpf) tailbud embryos as well as from 42 hpf larvae (after tail regression) in Ciona savignyi. Expression profiling of miRNAs was confirmed by quantitative real-time PCR, showing that the expression levels of csa-miR-4040, csa-miR-4086, csa-miR-4055, csa-miR-4060, csa-miR-216a, csa-miR-216b, csa-miR-217, csa-miR-183, and csa-miR-92c were significantly higher in 42 hpf larvae, whereas those of csa-miR-4018a, csa-miR-4018b, and csa-miR-4000f were higher in 18 and 21 hpf embryos; then, their expression in 42 hpf larvae became significantly low. For these 12 miRNAs, whose expression levels significantly changed, we predicted their target genes through the combination of miRanda and TargetScan. This prediction analysis revealed 332 miRNA-target gene pairs that were associated with the ERK, JNK, and transforming growth factor beta signaling pathways, suggesting that the identified miRNAs are involved in the regulation of C. savignyi larval metamorphosis via controlling the expression of their target genes. Furthermore, we validated the expression of five selected miRNAs by northern blotting. Among the selected miRNAs, the expression patterns of csa-miR-4018a, csa-miR-4018b, and csa-miR-4000f were further examined by whole-mount in situ hybridization. The results showed that all three miRNAs were specifically expressed in a cell population resembling mesenchymal cells at the head and trunk part in swimming larvae but not in metamorphic larvae. Utilizing the luciferase assay, we also confirmed that miR-4000f targeted Mapk1, suggesting that the csa-miR-4018a/csa-miR-4018b/csa-miR-4000f cluster regulates larval metamorphosis through the Mapk1-mediated signaling pathway. CONCLUSIONS Totally, 165 miRNAs, including 59 novel ones, were identified from the embryos and larvae of C. savignyi. Twelve of them showed significant changes in expression before and during metamorphosis. In situ hybridization and northern blotting results revealed that three miRNAs are potentially involved in the signaling regulatory network for the migration and differentiation of mesenchymal cells in larval metamorphosis. Furthermore, the luciferase reporter assay revealed that Mapk1 is a target of csa-miR-4000f. Our results not only present a list and profile of miRNAs involved in Ciona metamorphosis but also provide informative cues to further understand their function in ascidian larval metamorphosis.
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Affiliation(s)
- Xiaoming Zhang
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
| | - Xiaozhuo Liu
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
| | - Chengzhang Liu
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
- Key Laboratory of Experimental Marine Biology, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, 266071 China
| | - Jiankai Wei
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
| | - Haiyan Yu
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
| | - Bo Dong
- Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, Qingdao, 266003 China
- Laboratory for Marine Biology and Biotechnology, Qingdao National Laboratory for Marine Science and Technology, Qingdao, 266237 China
- Institute of Evolution and Marine Biodiversity, Ocean University of China, No. 5 Yushan Road, Qingdao, 266003 People’s Republic of China
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14
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Ferro D, Franchi N, Bakiu R, Ballarin L, Santovito G. Molecular characterization and metal induced gene expression of the novel glutathione peroxidase 7 from the chordate invertebrate Ciona robusta. Comp Biochem Physiol C Toxicol Pharmacol 2018; 205:1-7. [PMID: 29253620 DOI: 10.1016/j.cbpc.2017.12.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 12/08/2017] [Accepted: 12/12/2017] [Indexed: 11/28/2022]
Abstract
In the present study, we describe the identified and characterized the gene and the transcript of a novel glutathione peroxidase-7 (GPx7) from the solitary ascidian Ciona robusta, an invertebrate chordate widely distributed in temperate shallow seawater. The putative nucleotide and amino acid sequences were compared with those of GPx7 from other metazoans and phylogenetic analysis suggests the presence of a high evolutionary pressure in the contest of neutral evolution. The mRNA of CrGPx7 is located in hemocytes and ovarian follicular cells, as revealed by in situ hybridization. The time course of CrGPx7 mRNA levels in the presence of Cd, Cu and Zn, showed upregulation in the final stages of the experiments, suggesting a role of GPx7 in late protection from oxidative stress. Our in silico analyses of the crgpx7 promoter region revealed putative consensus sequences similar to mammalian metal-responsive elements (MRE) and xenobiotic-responsive elements (XRE), suggesting that the transcription of these genes directly depends on metals. Cell-free extract from C. robusta tissues show the presence of selenium-independent GPx activity that is inhibited by the presence of metals.
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Affiliation(s)
- D Ferro
- Institute for Evolution and Biodiversity, Westfälische Wilhelms-Universität, Münster, Germany
| | - N Franchi
- Department of Biology, University of Padova, Padova, Italy
| | - R Bakiu
- Department of Aquaculture and Fisheries, Agricultural University of Tirana, Tirana, Albania
| | - L Ballarin
- Department of Biology, University of Padova, Padova, Italy.
| | - G Santovito
- Department of Biology, University of Padova, Padova, Italy
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15
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Herbert RJH, Collins K, Mallinson J, Hall AE, Pegg J, Ross K, Clarke L, Clements T. Epibenthic and mobile species colonisation of a geotextile artificial surf reef on the south coast of England. PLoS One 2017; 12:e0184100. [PMID: 28926608 PMCID: PMC5604948 DOI: 10.1371/journal.pone.0184100] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 08/17/2017] [Indexed: 11/21/2022] Open
Abstract
With increasing coastal infrastructure and use of novel materials there is a need to investigate the colonisation of assemblages associated with new structures, how these differ to natural and other artificial habitats and their potential impact on regional biodiversity. The colonisation of Europe’s first artificial surf reef (ASR) was investigated at Boscombe on the south coast of England (2009–2014) and compared with assemblages on existing natural and artificial habitats. The ASR consists of geotextile bags filled with sand located 220m offshore on a sandy sea bed at a depth of 0-5m. Successional changes in epibiota were recorded annually on differently orientated surfaces and depths using SCUBA diving and photography. Mobile faunal assemblages were sampled using Baited Remote Underwater Video (BRUV). Distinct stages in colonisation were observed, commencing with bryozoans and green algae which were replaced by red algae, hydroids and ascidians, however there were significant differences in assemblage structure with depth and orientation. The reef is being utilised by migratory, spawning and juvenile life-history stages of fish and invertebrates. The number of non-native species was larger than on natural reefs and other artificial habitats and some occupied a significant proportion of the structure. The accumulation of 180 benthic and mobile taxa, recorded to date, appears to have arisen from a locally rich and mixed pool of native and non-native species. Provided no negative invasive impacts are detected on nearby protected reefs the creation of novel yet diverse habitats may be considered a beneficial outcome.
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Affiliation(s)
- Roger J. H. Herbert
- Bournemouth University, Department of Life and Environmental Sciences, Faculty of Science and Technology, Talbot Campus, Poole, Dorset, United Kingdom
- * E-mail:
| | - Ken Collins
- School of Ocean and Earth Science, University of Southampton, National Oceanography Centre, Waterfront Campus, European Way, Southampton, United Kingdom
| | - Jenny Mallinson
- School of Ocean and Earth Science, University of Southampton, National Oceanography Centre, Waterfront Campus, European Way, Southampton, United Kingdom
| | - Alice E. Hall
- Bournemouth University, Department of Life and Environmental Sciences, Faculty of Science and Technology, Talbot Campus, Poole, Dorset, United Kingdom
| | - Josephine Pegg
- University Centre Sparsholt, Sparsholt, Winchester, Hampshire, United Kingdom
| | - Kathryn Ross
- British Trust for Ornithology, Thetford, Norfolk, United Kingdom
| | - Leo Clarke
- Bournemouth University, Department of Life and Environmental Sciences, Faculty of Science and Technology, Talbot Campus, Poole, Dorset, United Kingdom
| | - Tom Clements
- School of Ocean and Earth Science, University of Southampton, National Oceanography Centre, Waterfront Campus, European Way, Southampton, United Kingdom
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16
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Onuma TA, Matsuo M, Nishida H. Modified whole-mount in situ hybridisation and immunohistochemistry protocols without removal of the vitelline membrane in the appendicularian Oikopleura dioica. Dev Genes Evol 2017; 227:367-374. [PMID: 28752326 DOI: 10.1007/s00427-017-0588-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 07/18/2017] [Indexed: 11/26/2022]
Abstract
The appendicularian Oikopleura dioica is a planktonic chordate that retains a tadpole shape throughout its life. Its simple and transparent body, invariant cell lineages, fast development and available genome and transcriptome resources make it a promising model organism for research in developmental biology. However, large-scale analysis of gene expression in O. dioica is limited owing to the laborious and time-consuming process of manual removal of the vitelline membrane, because devitellinisation of pre-hatching embryos causes failure of normal development. Therefore, in this study, modified procedures were developed for whole-mount in situ hybridisation (WISH) and immunohistochemistry (WIHC). This protocol enables rapid mRNA or protein detection without a manual devitellination step for each specimen. The critical procedure is brief treatment of the vitelline membrane of living embryos with 0.05% actinase E before fixation. Two minutes of treatment was optimal for the penetration of antisense RNA probes and antibodies through the vitelline membrane. This WISH protocol was applicable for chromogenic and fluorescent tyramide signal amplification reactions. Using the new protocol, we found eight genes with tissue-specific expression in the tail muscle, trunk epidermis, heart, pharynx, oesophagus, stomach or gill openings of developing larvae. This procedure also allowed for the detection of exogenous FLAG-tagged histone-enhanced green fluorescent protein by WIHC using anti-FLAG antibody. This study provides a useful and convenient tool for studying spatial and temporal gene expression patterns in this simple chordate model and should facilitate handling large amounts of genetic data from transcriptome-based approaches and other techniques such as treatments with chemical inhibitors.
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Affiliation(s)
- Takeshi A Onuma
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Osaka, Toyonaka, 560-0043, Japan.
| | | | - Hiroki Nishida
- Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Osaka, Toyonaka, 560-0043, Japan
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17
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Stabili L, Licciano M, Gravina MF, Giangrande A. Filtering activity on a pure culture of Vibrio alginolyticus by the solitary ascidian Styela plicata and the colonial ascidian Polyandrocarpa zorritensis: a potential service to improve microbiological seawater quality economically. Sci Total Environ 2016; 573:11-18. [PMID: 27552728 DOI: 10.1016/j.scitotenv.2016.07.216] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 07/29/2016] [Accepted: 07/30/2016] [Indexed: 06/06/2023]
Abstract
We investigated and compared, by laboratory experiments, the filter-feeding activity on bacteria by the solitary ascidian Styela plicata and the colonial ascidian Polyandrocarpa zorritensis. Clearance rates and retention efficiencies were estimated by using, as only food source, the bacterial species Vibrio alginolyticus selected on account of its importance in aquaculture pathogenicity. The Cmax was 1.4±0.17Lh-1g-1 DW for S. plicata and 1.745Lh-1g-1 DW for P. zorritensis. The highest retention efficiency was 41% corresponding to a removed bacterial biomass of 16.34+1.71 μgCL-1g-1 DW for P. zorritensis and 81% corresponding to a bacterial biomass of 32.28+2.15 μgCL-1g-1 DW for S. plicata. Styela plicata resulted higher efficient than P. zorritensis in removing V. alginolyticus from seawater in experimental tanks, thus representing a more suitable biofilter to restore the quality of microbiologically contaminated waters including those where aquaculture is practiced. Present laboratory experiments represent the first contribution to the comparison of the filtration activity of the two ascidians, as well as to characterize the filtration process on bacterioplankton and pone the basis for future field works aimed to restore bacteriological polluted seawater.
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Affiliation(s)
- Loredana Stabili
- Istituto per l'Ambiente Marino Costiero - Sezione di Taranto - CNR, Via Roma 3, 74100-Taranto, Italy; Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali (Di.S.Te.B.A.), Università del Salento, Via Prov. Lecce-Monteroni, 73100-Lecce, Italy.
| | - Margherita Licciano
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali (Di.S.Te.B.A.), Università del Salento, Via Prov. Lecce-Monteroni, 73100-Lecce, Italy.
| | - Maria Flavia Gravina
- Dipartimento di Biologia, Università degli Studi di Roma "Tor Vergata", Via della Ricerca Scientifica snc 00133, Roma.
| | - Adriana Giangrande
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali (Di.S.Te.B.A.), Università del Salento, Via Prov. Lecce-Monteroni, 73100-Lecce, Italy.
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18
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Cleary DFR, Polónia ARM, Renema W, Hoeksema BW, Rachello-Dolmen PG, Moolenbeek RG, Budiyanto A, Tuti Y, Draisma SGA, Prud'homme van Reine WF, Hariyanto R, Gittenberger A, Rikoh MS, de Voogd NJ. Variation in the composition of corals, fishes, sponges, echinoderms, ascidians, molluscs, foraminifera and macroalgae across a pronounced in-to-offshore environmental gradient in the Jakarta Bay-Thousand Islands coral reef complex. Mar Pollut Bull 2016; 110:701-17. [PMID: 27179997 DOI: 10.1016/j.marpolbul.2016.04.042] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 04/12/2016] [Accepted: 04/17/2016] [Indexed: 05/07/2023]
Abstract
Substrate cover, water quality parameters and assemblages of corals, fishes, sponges, echinoderms, ascidians, molluscs, benthic foraminifera and macroalgae were sampled across a pronounced environmental gradient in the Jakarta Bay-Thousand Islands reef complex. Inshore sites mainly consisted of sand, rubble and turf algae with elevated temperature, dissolved oxygen, pH and chlorophyll concentrations and depauperate assemblages of all taxa. Live coral cover was very low inshore and mainly consisted of sparse massive coral heads and a few encrusting species. Faunal assemblages were more speciose and compositionally distinct mid- and offshore compared to inshore. There were, however, small-scale differences among taxa. Certain midshore sites, for example, housed assemblages resembling those typical of the inshore environment but this differed depending on the taxon. Substrate, water quality and spatial variables together explained from 31% (molluscs) to 72% (foraminifera) of the variation in composition. In general, satellite-derived parameters outperformed locally measured parameters.
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Affiliation(s)
- D F R Cleary
- Department of Biology, CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - A R M Polónia
- Department of Biology, CESAM, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal
| | - W Renema
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands
| | - B W Hoeksema
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands; Institute of Biology (IBL), Leiden University, P.O. Box 9516, 2300 RA Leiden, The Netherlands
| | - P G Rachello-Dolmen
- Smithsonian Tropical Research Institute, Naos Island Marine Laboratory, Panama City 20521-9100, Panama; Dept. of Geology & Geophysics, Texas A&M University, College Station, TX 77843, United States
| | - R G Moolenbeek
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands
| | - A Budiyanto
- Research Centre for Oceanography, Indonesian Institute of Sciences, Pasir Putih 1, Ancol Timur, Jakarta Utara 11048, Indonesia
| | - Y Tuti
- Research Centre for Oceanography, Indonesian Institute of Sciences, Pasir Putih 1, Ancol Timur, Jakarta Utara 11048, Indonesia
| | - S G A Draisma
- Center of Excellence for Biodiversity of Peninsular Thailand, Faculty of Science, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand
| | | | - R Hariyanto
- Research Centre for Oceanography, Indonesian Institute of Sciences, Pasir Putih 1, Ancol Timur, Jakarta Utara 11048, Indonesia
| | - A Gittenberger
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands; Institute of Biology (IBL), Leiden University, P.O. Box 9516, 2300 RA Leiden, The Netherlands; GiMaRIS, J.H. Oortweg 21, 2333 CH Leiden, The Netherlands
| | - M S Rikoh
- Research Centre for Oceanography, Indonesian Institute of Sciences, Pasir Putih 1, Ancol Timur, Jakarta Utara 11048, Indonesia
| | - N J de Voogd
- Naturalis Biodiversity Center, Darwinweg 2, 2333 CR Leiden, The Netherlands.
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Abstract
Important contributions to evolutionary developmental biology have been made using the comparative organismal approach. As examples, I describe insights obtained from studies of Molgula ascidians and Astyanax cavefish.
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Affiliation(s)
- William R Jeffery
- Department of Biology, University of Maryland, College Park, Maryland, USA.
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20
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Peck LS, Clark MS, Power D, Reis J, Batista FM, Harper EM. Acidification effects on biofouling communities: winners and losers. Glob Chang Biol 2015; 21:1907-1913. [PMID: 25626420 PMCID: PMC5006883 DOI: 10.1111/gcb.12841] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 11/22/2014] [Indexed: 05/28/2023]
Abstract
How ocean acidification affects marine life is a major concern for science and society. However, its impacts on encrusting biofouling communities, that are both the initial colonizers of hard substrata and of great economic importance, are almost unknown. We showed that community composition changed significantly, from 92% spirorbids, 3% ascidians and 4% sponges initially to 47% spirorbids, 23% ascidians and 29% sponges after 100 days in acidified conditions (pH 7.7). In low pH, numbers of the spirorbid Neodexiospira pseudocorrugata were reduced ×5 compared to controls. The two ascidians present behaved differently with Aplidium sp. decreasing ×10 in pH 7.7, whereas Molgula sp. numbers were ×4 higher in low pH than controls. Calcareous sponge (Leucosolenia sp.) numbers increased ×2.5 in pH 7.7 over controls. The diatom and filamentous algal community was also more poorly developed in the low pH treatments compared to controls. Colonization of new surfaces likewise showed large decreases in spirorbid numbers, but numbers of sponges and Molgula sp. increased. Spirorbid losses appeared due to both recruitment failure and loss of existing tubes. Spirorbid tubes are comprised of a loose prismatic fabric of calcite crystals. Loss of tube materials appeared due to changes in the binding matrix and not crystal dissolution, as SEM analyses showed crystal surfaces were not pitted or dissolved in low pH conditions. Biofouling communities face dramatic future changes with reductions in groups with hard exposed exoskeletons and domination by soft-bodied ascidians and sponges.
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Affiliation(s)
- Lloyd S. Peck
- British Antarctic SurveyHigh Cross, Madingley RdCambridgeCB3 0ETUK
| | - Melody S. Clark
- British Antarctic SurveyHigh Cross, Madingley RdCambridgeCB3 0ETUK
| | - Deborah Power
- University of the AlgarveCtr Ciencias MarP‐8000139FaroPortugal
| | - João Reis
- University of the AlgarveCtr Ciencias MarP‐8000139FaroPortugal
| | - Frederico M. Batista
- University of the AlgarveCtr Ciencias MarP‐8000139FaroPortugal
- Instituto Português do Mar e da Atmosfera (IPMA)Estação Experimental de Moluscicultura de TaviraVale Caranguejo8800TaviraPortugal
| | - Elizabeth M. Harper
- Department of Earth SciencesUniversity of CambridgeDowning StreetCambridgeCB2 3EQUK
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Shaala LA, Youssef DTA. Identification and bioactivity of compounds from the fungus Penicillium sp. CYE-87 isolated from a marine tunicate. Mar Drugs 2015; 13:1698-709. [PMID: 25815893 PMCID: PMC4413182 DOI: 10.3390/md13041698] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Revised: 03/13/2015] [Accepted: 03/18/2015] [Indexed: 11/26/2022] Open
Abstract
In the course of our continuous interest in identifying bioactive compounds from marine microbes, we have investigated a tunicate-derived fungus, Penicillium sp. CYE-87. A new compound with the 1,4-diazepane skeleton, terretrione D (2), together with the known compounds, methyl-2-([2-(1H-indol-3-yl)ethyl]carbamoyl)acetate (1), tryptamine (3), indole-3-carbaldehyde (4), 3,6-diisobutylpyrazin-2(1H)-one (5) and terretrione C (6), were isolated from Penicillium sp. CYE-87. The structures of the isolated compounds were established by spectral analysis, including 1D (1H, 13C) and 2D (COSY, multiplicity edited-HSQC and HMBC) NMR and HRESIMS, as well as comparison of their NMR data with those in the literature. The compounds were evaluated for their antimigratory activity against the human breast cancer cell line (MDA-MB-231) and their antiproliferation activity against HeLa cells. Compounds 2 and 6 showed significant antimigratory activity against MDA-MB-231, as well as antifungal activity against C. albicans.
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Affiliation(s)
- Lamiaa A Shaala
- Natural Products Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
- Suez Canal University Hospital, Suez Canal University, Ismailia 51522, Egypt.
| | - Diaa T A Youssef
- Department of Natural Products, Faculty of Pharmacy, King Abdulaziz University, Jeddah 21589, Saudi Arabia.
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22
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McCann LD, Holzer KK, Davidson IC, Ashton GV, Chapman MD, Ruiz GM. Promoting invasive species control and eradication in the sea: options for managing the tunicate invader Didemnum vexillum in Sitka, Alaska. Mar Pollut Bull 2013; 77:165-171. [PMID: 24449921 DOI: 10.1016/j.marpolbul.2013.10.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Bioinvasions are a significant force of change--and economic and ecological threat--in marine ecosystems. The threat now encroaches on Alaska, which has had relatively few invasions compared to other global regions, prompting need to develop new incursion response tools. We appraised five 'eco-friendly' immersion treatment options (dilute acetic acid, dilute bleach, freshwater, brine and hypoxia) at either minute- or hour-scale exposures to kill the invasive tunicate Didemnum vexillum. Data revealed 100% treatment efficacy after two minutes in acetic acid, ten minutes in bleach, four hours in freshwater and over four hours in brine solution. We also demonstrated the importance of monitoring D. vexillum recovery for at least three weeks, since seemingly destroyed colonies rebounded during this timeframe. Combined, these findings provide insights towards a bay-scale eradication and post-border management plan applicable to the recent D. vexillum incursion in Whiting Harbor, Alaska and other shallow, inshore invasion sites.
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Gallo A, Tosti E. Adverse effect of antifouling compounds on the reproductive mechanisms of the ascidian Ciona intestinalis. Mar Drugs 2013; 11:3554-68. [PMID: 24065165 PMCID: PMC3806468 DOI: 10.3390/md11093554] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2013] [Revised: 08/20/2013] [Accepted: 08/27/2013] [Indexed: 11/16/2022] Open
Abstract
Fertilization and embryo development that occur in sea water are sensitive to xenobiotics from anthropogenic sources. In this work, we evaluated the influence of two antifouling biocides, tributyltin (TBT) and diuron, on the reproductive mechanisms of the marine invertebrate Ciona intestinalis. By using electrophysiological techniques, we examined the impact of these compounds on the electrical properties of the mature oocytes and of events occurring at fertilization. With different toxicity assays, we studied the effect of the two biocides on the gametes by evaluating fertilization rate and embryo development. Results show that sodium (Na⁺) currents were significantly reduced by either of the two biocides, whereas conductance was significantly increased. The fertilization current frequency and amplitude, fertilization rate and larval development were affected only by TBT. This study suggests that: (i) the two biocides affect either the electrical properties of the oocyte plasma membrane and the reproductive success representing a risk factor for the survival of the species exposed to environmental pollution; (ii) the ascidian Ciona intestinalis may represent a good model organism to test toxicity of marine pollutants. Possible mechanisms of action of the two biocides are discussed.
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Affiliation(s)
| | - Elisabetta Tosti
- Laboratory of Animal Physiology and Evolution, Stazione Zoologica Anton Dohrn, Villa Comunale, Naples 80121, Italy; E-Mail:
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24
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Abstract
Marine invertebrates commonly have a biphasic life cycle in which the metamorphic transition from a pelagic larva to a benthic post-larva is mediated by the nitric oxide signalling pathway. Nitric oxide (NO) is synthesised by nitric oxide synthase (NOS), which is a client protein of the molecular chaperon heat shock protein 90 (HSP90). It is notable, then, that both NO and HSP90 have been implicated in regulating metamorphosis in marine invertebrates as diverse as urochordates, echinoderms, molluscs, annelids, and crustaceans. Specifically, the suppression of NOS activity by the application of either NOS- or HSP90-inhibiting pharmacological agents has been shown consistently to induce the initiation of metamorphosis, leading to the hypothesis that a negative regulatory role of NO is widely conserved in biphasic life cycles. Further, the induction of metamorphosis by heat-shock has been demonstrated for multiple species. Here, we investigate the regulatory role of NO in induction of metamorphosis of the solitary tropical ascidian, Herdmania momus. By coupling pharmacological treatments with analysis of HmNOS and HmHSP90 gene expression, we present compelling evidence of a positive regulatory role for NO in metamorphosis of this species, in contrast to all existing ascidian data that supports the hypothesis of NO as a conserved negative regulator of metamorphosis. The exposure of competent H. momus larvae to a NOS inhibitor or an NO donor results in an up-regulation of NOS and HSP90 genes. Heat shock of competent larvae induces metamorphosis in a temperature dependent manner, up to a thermal tolerance that approaches 35°C. Both larval/post-larval survival and the appearance of abnormal morphologies in H. momus post-larvae reflect the magnitude of up-regulation of the HSP90 gene in response to heat-shock. The demonstrated role of NO as a positive metamorphic regulator in H. momus suggests the existence of inter-specific adaptations of NO regulation in ascidian metamorphosis.
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Affiliation(s)
- Nobuo Ueda
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
| | - Sandie M. Degnan
- School of Biological Sciences, University of Queensland, Brisbane, Queensland, Australia
- * E-mail:
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25
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Cahill PL, Heasman K, Jeffs A, Kuhajek J. Laboratory assessment of the antifouling potential of a soluble-matrix paint laced with the natural compound polygodial. Biofouling 2013; 29:967-975. [PMID: 23919801 DOI: 10.1080/08927014.2013.822488] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Polygodial is a potent and selective inhibitor of ascidian metamorphosis that shows promise for controlling fouling by ascidians in bivalve aquaculture. The current study examined the potency of, and associated effects of seawater exposure on, a rosin-based soluble-matrix paint laced with 0.08-160 ng polygodial g(-1) wet paint matrix. Paint-coated surfaces were soaked in seawater for 0, 2, 4 or 12 weeks prior to screening for antifouling activity using a bioassay based on the nuisance ascidian Ciona savignyi Herdman. Mortality was greater (mean 50% lethal concentration: 5 ± 2 ng g(-1); mean 75% lethal concentration: 17 ± 4 ng g(-1)) and metamorphosis was inhibited (mean 50% anti-metamorphic concentration: 2 ± 0.4 ng g(-1); mean 75% anti-metamorphic concentration: 15 ± 10 ng g(-1)) in C. savignyi larvae exposed to polygodial-laced soluble-matrix paints, relative to control paints without polygodial. Soaking in seawater prior to testing reduced the efficacy of the formulation up to nearly 12-fold, but even after soaking for 12 weeks paints laced with polygodial at 160 ng g(-1) wet paint matrix prevented ⩾90% of the larvae of C. savignyi from completing metamorphosis. The outcome of this experiment provides a positive first step in evaluating the suitability of polygodial-laced soluble-matrix paints for use in aquaculture.
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Abstract
The larvae of non-vertebrate chordate ascidians consist of countable numbers of cells. With this feature, ascidians provide us with excellent models for studying cellular events in the construction of the chordate body. This review discusses the recent observations of morphogenetic movements and cell cycles and divisions along with tissue specifications during ascidian embryogenesis. Unequal cleavages take place at the posterior blastomeres during the early cleavage stages of ascidians, and the structure named the centrosome-attracting body restricts the position of the nuclei near the posterior pole to achieve the unequal cleavages. The most-posterior cells differentiate into the primordial germ cells. The gastrulation of ascidians starts as early as the 110-cell stage. During gastrulation, the endodermal cells show two-step changes in cell shape that are crucial for gastrulation. The ascidian notochord is composed of only 40 cells. The 40 cells align to form a single row by an event named the convergent extension, and then the notochord cells undergo vacuolation to transform the notochord into a single hollowed tube. The strictly restricted number of notochord cells is achieved by the regulated number of cell divisions coupled with the differentiation of the cells conducted by a key transcription factor, Brachyury. The dorsally located neural tube is a characteristic of chordates. During the closure of the ascidian neural tube, the epidermis surrounding the neural plate moves toward the midline to close the neural fold. This morphogenetic movement is allowed by an elongation of interphase in the epidermal cell cycles.
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Affiliation(s)
- Yosuke Ogura
- Shimoda Marine Research Center, University of Tsukuba, Shizuoka, Japan
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27
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Sievers M, Fitridge I, Dempster T, Keough MJ. Biofouling leads to reduced shell growth and flesh weight in the cultured mussel Mytilus galloprovincialis. Biofouling 2013; 29:97-107. [PMID: 23256892 DOI: 10.1080/08927014.2012.749869] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Competitive interactions between cultured mussels and fouling organisms may result in growth and weight reductions in mussels, and compromised aquaculture productivity. Mussel ropes were inoculated with Ciona intestinalis, Ectopleura crocea or Styela clava, and growth parameters of fouled and unfouled Mytilus galloprovincialis were compared after two months. Small mussels (≈ 50 mm) fouled by C. intestinalis and E. crocea were 4.0 and 3.2% shorter in shell length and had 21 and 13% reduced flesh weight, respectively, compared to the controls. Large mussels (≈ 68 mm) fouled by S. clava, C. intestinalis and E. crocea were 4.4, 3.9 and 2.1% shorter than control mussels, respectively, but flesh weights were not significantly reduced. A series of competitive feeding experiments indicated that S. clava and C. intestinalis did not reduce mussels' food consumption, but that E. crocea, through interference competition, did. Fouling by these species at the densities used here reduced mussel growth and flesh weight, likely resulting in economic losses for the industry, and requires consideration when developing biofouling mitigation strategies.
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Affiliation(s)
- Michael Sievers
- Sustainable Aquaculture Laboratory - Temperate and Tropical (SALTT), Department of Zoology, University of Melbourne, Victoria, Australia.
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Rius M, Shenkar N. Ascidian introductions through the Suez Canal: The case study of an Indo-Pacific species. Mar Pollut Bull 2012; 64:2060-2068. [PMID: 22857711 DOI: 10.1016/j.marpolbul.2012.06.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2012] [Revised: 06/27/2012] [Accepted: 06/28/2012] [Indexed: 06/01/2023]
Abstract
Although marine biological invasions via the Suez Canal have been extensively documented, little is known about the introduction of non-indigenous ascidians (Chordata, Ascidiacea), a group containing particularly aggressive invasive species. Here, we used a multidisciplinary approach to study the introduction of the ascidian Herdmania momus into the Mediterranean Sea. We reviewed its taxonomy and global distribution, and analyzed how genetic variation is partitioned between sides of the Suez Canal. The taxonomic revision showed that H. momus currently has a wide Indo-Pacific distribution. Genetic data indicated two well-differentiated colonization histories across the eastern Mediterranean. Our findings suggest that the range expansion of H. momus has been greatly facilitated by the combined effect of human-mediated transport and the species' ability to adapt to different environments. The integrative approach presented here is critical to attain a holistic understanding of marine biological invasions, especially when studying groups with a poorly resolved taxonomy.
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Affiliation(s)
- Marc Rius
- Department of Evolution and Ecology, University of California, Davis, USA.
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29
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Smith KF, Stefaniak L, Saito Y, Gemmill CEC, Cary SC, Fidler AE. Increased inter-colony fusion rates are associated with reduced COI haplotype diversity in an invasive colonial ascidian Didemnum vexillum. PLoS One 2012; 7:e30473. [PMID: 22303442 PMCID: PMC3269411 DOI: 10.1371/journal.pone.0030473] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2011] [Accepted: 12/20/2011] [Indexed: 11/18/2022] Open
Abstract
Considerable progress in our understanding of the population genetic changes associated with biological invasions has been made over the past decade. Using selectively neutral loci, it has been established that reductions in genetic diversity, reflecting founder effects, have occurred during the establishment of some invasive populations. However, some colonial organisms may actually gain an ecological advantage from reduced genetic diversity because of the associated reduction in inter-colony conflict. Here we report population genetic analyses, along with colony fusion experiments, for a highly invasive colonial ascidian, Didemnum vexillum. Analyses based on mitochondrial cytochrome oxidase I (COI) partial coding sequences revealed two distinct D. vexillum clades. One COI clade appears to be restricted to the probable native region (i.e., north-west Pacific Ocean), while the other clade is present in widely dispersed temperate coastal waters around the world. This clade structure was supported by 18S ribosomal DNA (rDNA) sequence data, which revealed a one base-pair difference between the two clades. Recently established populations of D. vexillum in New Zealand displayed greatly reduced COI genetic diversity when compared with D. vexillum in Japan. In association with this reduction in genetic diversity was a significantly higher inter-colony fusion rate between randomly paired New Zealand D. vexillum colonies (80%, standard deviation ±18%) when compared with colonies found in Japan (27%, standard deviation ±15%). The results of this study add to growing evidence that for colonial organisms reductions in population level genetic diversity may alter colony interaction dynamics and enhance the invasive potential of newly colonizing species.
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30
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Cahill P, Heasman K, Jeffs A, Kuhajek J, Mountfort D. Preventing ascidian fouling in aquaculture: screening selected allelochemicals for anti-metamorphic properties in ascidian larvae. Biofouling 2012; 28:39-49. [PMID: 22235790 DOI: 10.1080/08927014.2011.648624] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Fouling by ascidians causes major stock losses and disrupts production in marine aquaculture, especially bivalve aquaculture. Currently, no cost effective solution exists despite the testing of many prospective control techniques. This study examined a range of allelochemicals suspected to inhibit metamorphosis in marine larvae. Five allelochemicals were screened in a larval metamorphosis bioassay using Ciona savignyi Herdman to determine their potential as a remedy for ascidian fouling in bivalve aquaculture. Three of the compounds tested inhibited ascidian larval metamorphosis and increased mortality at low concentrations. These were radicicol (99% inhibition of metamorphosis [IC₉₉], 0.8 μg ml⁻¹; 99% lethal concentration [LC₉₉], 2.5 μg ml⁻¹; 99% lethal time [LT₉₉], 7.0 days), polygodial (IC₉₉, 0.003 μg ml⁻¹; LC₉₉, 0.9 μg ml⁻¹; LT₉₉, 6.4 days), and ubiquinone-10 (IC₉₉, 3.2 μg cm⁻²; LC₉₉, 14.5 μg cm⁻²; LT₉₉, 5.6 days; expressed as μg cm⁻² due to insolubility in water and ethanol). While spermidine significantly affected metamorphosis and mortality of C. savignyi, the effect was insufficient to achieve inhibition in 99% of larvae over the 7-day timeframe of the assay. Muscimol did not affect metamorphosis or mortality at the concentrations tested. The present study demonstrates that radicicol, polygodial and ubiquinone-10 have potential for future development in antifoulant formulations targeted towards the inhibition of metamorphosis in ascidian larvae, while spermidine and muscimol appear unsuitable.
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Abstract
Artificial structures associated with shipping and boating activities provide habitats for a diverse suite of non-indigenous marine species. Little is known about the proportion of invader success in nearby waters that is attributable to these structures. Areas close to piles, wharves and piers are likely to be exposed to increasing levels of propagule pressure, enhancing the recruitment of non-indigenous species. Recruitment of non-indigenous and native marine biofouling taxa were evaluated at different distances from a large commercial shipping pier. Since artificial structures also represent a desirable habitat for fish, how predation on marine invertebrates influences the establishment of non-indigenous and native species was also evaluated. The colonisation of several non-indigenous marine species declined rapidly with distance from the structure. Little evidence was found to suggest that predators have much influence on the colonisation success of marine sessile invertebrate species, non-indigenous or otherwise. It is suggested that propagule pressure, not predation, more strongly predicts establishment success in these biofouling assemblages.
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Affiliation(s)
- Luke H Hedge
- Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, The University of New South Wales, Sydney, NSW, Australia.
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32
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Abstract
Regeneration is widely distributed among the metazoans. However, clear differences exist as to the degree of regenerative capacity: some phyla can only replace missing body parts, whereas others can generate entirely new individuals. Ascidians are animals that possess a remarkable regenerative plasticity and exhibit a great diversity of mechanisms for asexual propagation and survival. They are marine invertebrate members of the subphylum Tunicata and represent modern-day descendants of the chordate ancestor; in their tadpole stage they exhibit a chordate body plan that is resorbed during metamorphosis. Solitary species grow into an adult that can reach several centimeters in length, whereas colonial species grow by asexual propagation, creating a colony of genetically identical individuals. In this review, we present an overview of the biology of colonial ascidians as a paradigm for study in stem cell and regenerative biology. Focusing on botryllid ascidians, we introduce the potential roles played by multipotent epithelia and multipotent/pluripotent stem cells as source of asexual propagation and regenerative plasticity in the different budding mechanisms, and consider the putative mechanism of body repatterning in a non-embryonic scenario. We also discuss the involvement of intra-colony homeostatic processes in regulating budding potential, and the functional link between allorecognition, chimerism, and regenerative potential.
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Affiliation(s)
- Ulrich Kürn
- Zoological Institute, Christian-Albrechts-University Kiel, Olshausenstrasse, Germany
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33
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Nakashima K, Nishino A, Hirose E. Forming a tough shell via an intracellular matrix and cellular junctions in the tail epidermis of Oikopleura dioica (Chordata: Tunicata: Appendicularia). Naturwissenschaften 2011; 98:661-9. [PMID: 21667277 DOI: 10.1007/s00114-011-0815-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Revised: 05/31/2011] [Accepted: 06/01/2011] [Indexed: 11/26/2022]
Abstract
A postanal tail is a major synapomorphy of the phylum Chordata, which is composed of three subphyla: Vertebrata, Cephalochordata, and Tunicata (Urochordata). Among tunicates, appendicularians are the only group that retains the tail in the adult, and the adult tail functions in locomotion and feeding in combination with a cellulose-based house structure. Given the phylogenetic position of tunicates, the appendicularian adult tail may possess ancestral features of the chordate tail. We assess the ultrastructural development of the tail epidermis of the appendicularian Oikopleura dioica. The epidermis of the larval tail is enclosed by the larval envelope, which is a thin sheet similar to the outer tunic layer of ascidian larvae. The epidermis of the adult tail seems to bear no tunic-like cellulosic integuments, and the tail fin is a simple folding of the epidermis. Every epidermal cell, except for the triangular cells at the edge of the tail fin, has a conspicuous matrix layer of fibrous content in the apical cytoplasm without enclosing membranes. The epidermis of the larval tail does not have a fibrous matrix layer, suggesting the production of the layer during larval development and metamorphosis. Zonulae adhaerentes firmly bind the epidermal cells of the adult tail to one another, and the dense microfilaments lining the cell borders constitute a mechanical support for the cell membranes. The intracellular matrix, cell junctions, and cytoskeletons probably make the tail epidermis a tough, flexible shell supporting the active beating of the oikopleuran adult tail.
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Affiliation(s)
- Keisuke Nakashima
- Marine Genomics Unit, Okinawa Institute of Science and Technology Promotion Corporation, 1919-1 Tancha, Onna, Okinawa 904-0412, Japan
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34
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Carpenter MA, Powell JH, Ishizuka KJ, Palmeri KJ, Rendulic S, De Tomaso AW. Growth and long-term somatic and germline chimerism following fusion of juvenile Botryllus schlosseri. Biol Bull 2011; 220:57-70. [PMID: 21385958 PMCID: PMC4265767 DOI: 10.1086/bblv220n1p57] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The colonial ascidian Botryllus schlosseri undergoes a histocompatibility reaction that can result in vascular fusion of distinct genotypes, creating a chimera. Chimerism has both potential benefits, such as an immediate increase in size that may enhance growth rates, and costs. For the latter, the presence of multiple genotypes in a chimera can lead to competition between genetically distinct stem cell lineages, resulting in complete replacement of somatic and germline tissues by a single genotype. Although fusion can occur at any point after metamorphosis, previous studies have focused on chimeras created from sexually mature adults, where no benefit to chimerism has been documented. Here we focus on the costs and benefits of fusion between juveniles, characterizing growth rates and patterns of somatic and germline chimerism after natural and controlled fusion events. We also compared outcomes between low- and high-density growth conditions, the latter more likely representative of what occurs in natural populations. We found that growth rates were density-dependent, and that only chimeras grew under high-density conditions. We also observed a positional component to a post-fusion event called resorption, indicating that extrinsic factors were important in this process. Patterns of germline and somatic chimerism and dominance in chimeras made from fused juveniles were equivalent to those after fusion of sexually mature adults, and there were no age-related differences in these processes. Finally, by using genetic markers that could retrospectively assign genotypes, we also found that the majority of individual testes in a chimera were clonally derived.
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Affiliation(s)
| | - John H. Powell
- Department of Ecology, Montana State University, Bozeman, Montana 59717
| | | | - Karla J. Palmeri
- Stanford University, Hopkins Marine Station, Pacific Grove, California 93950
| | - Snjezana Rendulic
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California 93106
| | - Anthony W. De Tomaso
- Department of Molecular, Cellular and Developmental Biology, University of California, Santa Barbara, Santa Barbara, California 93106
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35
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Affiliation(s)
- Max E Maliska
- Biology Department, University of Washington, Seattle, WA 98195, USA
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36
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Brown FD, Tiozzo S, Roux MM, Ishizuka K, Swalla BJ, De Tomaso AW. Early lineage specification of long-lived germline precursors in the colonial ascidian Botryllus schlosseri. Development 2009; 136:3485-94. [PMID: 19783737 PMCID: PMC2752397 DOI: 10.1242/dev.037754] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2009] [Indexed: 11/20/2022]
Abstract
In many taxa, germline precursors segregate from somatic lineages during embryonic development and are irreversibly committed to gametogenesis. However, in animals that can propagate asexually, germline precursors can originate in adults. Botryllus schlosseri is a colonial ascidian that grows by asexual reproduction, and on a weekly basis regenerates all somatic and germline tissues. Embryonic development in solitary ascidians is the classic example of determinative specification, and we are interested in both the origins and the persistence of stem cells responsible for asexual development in colonial ascidians. In this study, we characterized vasa as a putative marker of germline precursors. We found that maternally deposited vasa mRNA segregates early in development to a posterior lineage of cells, suggesting that germline formation is determinative in colonial ascidians. In adults, vasa expression was observed in the gonads, as well as in a population of mobile cells scattered throughout the open circulatory system, consistent with previous transplantation/reconstitution results. vasa expression was dynamic during asexual development in both fertile and infertile adults, and was also enriched in a population of stem cells. Germline precursors in juveniles could contribute to gamete formation immediately upon transplantation into fertile adults, thus vasa expression is correlated with the potential for gamete formation, which suggests that it is a marker for embryonically specified, long-lived germline progenitors. Transient vasa knockdown did not have obvious effects on germline or somatic development in adult colonies, although it did result in a profound heterochrony, suggesting that vasa might play a homeostatic role in asexual development.
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Affiliation(s)
- Federico D Brown
- Biology Department, Center for Developmental Biology, and Institute for Stem Cell and Regenerative Medicine, University of Washington, Seattle, WA 98195, USA
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37
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Sunanaga T, Saito Y, Kawamura K. Postembryonic epigenesis of Vasa-positive germ cells from aggregated hemoblasts in the colonial ascidian, Botryllus primigenus. Dev Growth Differ 2009; 48:87-100. [PMID: 16512853 DOI: 10.1111/j.1440-169x.2006.00849.x] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
We investigated whether Vasa was a germline-specific marker in the colonial ascidian Botryllus primigenus, and whether it was inducible epigenetically in the adult life span. We cloned a Botryllus Vasa homologue (BpVas). The deduced open reading frame encoded 687 amino acid residues. It was expressed specifically by germline cells such as the loose cell mass, oogonia and juvenile oocytes in the ovary, and the primordial testis (compact cell mass), spermatogonia and juvenile spermatocytes in the testis. The loose cell mass, the most primitive germline cells, showed an ultrastructure of undifferentiated cells known as hemoblasts. The hemoblasts did not contain electron-dense materials or a mitochondrial assembly in the cytoplasm. These organelles appeared later in the oogonia and oocytes. When the loose cell mass and developing germ cells were eliminated by extirpating all zooids and buds from the colonies, BpVas transcripts disappeared completely from the vascularized colonies. After 14 days, when the colonies regenerated by vascular budding, BpVas-positive cells reappeared in some cases, and in 30 day colonies, BpVas-positive germ cells were observed in all the regenerated colonies. These results show that in B. primigenus, germ cells are inducible de novo from the Vasa-negative cells even at postembryonic stages.
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Affiliation(s)
- Takeshi Sunanaga
- Laboratory of Cellular and Molecular Biotechnology, Faculty of Science, Kochi University, Kochi 780-8520, Japan.
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Scardino AJ, Hudleston D, Peng Z, Paul NA, de Nys R. Biomimetic characterisation of key surface parameters for the development of fouling resistant materials. Biofouling 2009; 25:83-93. [PMID: 18985468 DOI: 10.1080/08927010802538480] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Material science provides a direct route to developing a new generation of non-toxic, surface effect-based antifouling technologies with applications ranging from biomedical science to marine transport. The surface topography of materials directly affects fouling resistance and fouling removal, the two key mechanisms for antifouling technologies. However, the field is hindered by the lack of quantified surface characteristics to guide the development of new antifouling materials. Using a biomimetic approach, key surface parameters are defined and quantified and correlated with fouling resistance and fouling removal from the shells of marine molluscs. Laser scanning confocal microscopy was used to acquire images for quantitative surface characterisation using three-dimensional surface parameters, and field assays correlated these with fouling resistance and fouling release. Principle component analysis produced a major component (explaining 54% of total variation between shell surfaces) that correlated with fouling resistance. The five surface parameters positively correlated to increased fouling resistance were, in order of importance, low fractal dimension, high skewness of both the roughness and waviness profiles, higher values of isotropy and lower values of mean surface roughness. The second component (accounting for 20% of variation between shells) positively correlated to fouling release, for which higher values of mean waviness almost exclusively dictated this relationship. This study provides quantified surface parameters to guide the development of new materials with surface properties that confer fouling resistance and release.
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Affiliation(s)
- A J Scardino
- School of Marine and Tropical Biology, James Cook University, Queensland, Australia.
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Chae J, Choi HW, Lee WJ, Kim D, Lee JH. Distribution of a pelagic tunicate, Salpa fusiformis in warm surface current of the eastern Korean waters and its impingement on cooling water intakes of Uljin nuclear power plant. J Environ Biol 2008; 29:585-590. [PMID: 19195402] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Impingement of a large amount of gelatinous plankton, Salpa fusiformis on the seawater intake system-screens in a nuclear power plant at Uljin was firstly recorded on 18th June 2003. Whole amount of the clogged animals was estimated were presumptively at 295 tons and the shortage of cooling seawater supply by the animal clogging caused 38% of decrease in generation capability of the power plant. Zooplankton collection with a multiple towing net during the day and at night from 5 to 6 June 2003 included various gelatinous zooplanktons known to be warm water species such as salps and siphonophores. Comparatively larger species, Salpa fusiformis occupied 25.4% in individual density among the gelatinous plankton and showed surface distribution in the depth shallower than thermocline, performing little diel vertical migration. Temperature, salinity and satellite data also showed warm surface current predominated over the southern coastal region near the power plant in June. The results suggested that warm surface current occasionally extended into the neritic region may transfer S. fusiformis, to the waters off the power plant. The environmental factors and their relation to ecobiology of the large quantity of salpa population that are being sucked into the intake channel of the power plant are discussed.
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Affiliation(s)
- Jinho Chae
- Korea Environmental Research Center for Hydrosphere, 634-1 Yi dong, Sangnok gu, Ansan, Gyeonggi do 426-857, Republic of Korea.
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40
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Abstract
The genomes of many marine invertebrates, including the purple sea urchin and the solitary ascidians Ciona intestinalis and Ciona savignyi, show exceptionally high levels of heterozygosity, implying that these populations are highly polymorphic. Analysis of the C. savignyi genome found little evidence to support an elevated mutation rate, but rather points to a large population size contributing to the polymorphism level. In the present study, the relative genetic polymorphism levels in sampled populations of ten different ascidian species were determined using a similarity index generated by AFLP analysis. The goal was to determine the range of polymorphism within the populations of different species, and to uncover factors that may contribute to the high level of polymorphism. We observe that, surprisingly, the levels of polymorphism within these species show a negative correlation with the reported age of invasive populations, and that closely related species show substantially different levels of genetic polymorphism. These findings show exceptions to the assumptions that invasive species start with a low level of genetic polymorphism that increases over time and that closely related species have similar levels of genetic polymorphism.
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Affiliation(s)
- Nathan Silva
- Interdepartmental Graduate Program in Marine Science, University of California Santa Barbara, Santa Barbara, California, United States of America
| | - William C. Smith
- Interdepartmental Graduate Program in Marine Science, University of California Santa Barbara, Santa Barbara, California, United States of America
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, California, United States of America
- * E-mail:
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41
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Ishii T, Hirose E, Taneda Y. Tunic phagocytes are involved in allorejection reaction in the colonial tunicate Aplidium yamazii (Polyclinidae, Ascidiacea). Biol Bull 2008; 214:145-152. [PMID: 18400996 DOI: 10.2307/25066671] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
The colonial ascidian Aplidium yamazii exhibited an allorejection reaction when two allogeneic colonies were brought into contact at their growing edges or at artificial cut surfaces. This species has no vascular network in the tunic, unlike the botryllid ascidians, which have a vascular network throughout the colony's common tunic. In the allorejection reaction induced by contact at the growing edges, some small, hard-packed tunic masses were formed at the contact points. Histological and electron microscopic investigation of these tunic masses revealed that they contained aggregates of tunic cells, with tunic phagocytes being the major cell type present. Some of the tunic phagocytes in these tunic masses appeared to be disintegrating. When allogeneic colonies were placed in contact at their artificial cut surfaces, the colonies partially fused, then separated. In this allorejection reaction, some loosely packed tunic masses remained in the gap between the two withdrawn colonies. These results strongly suggest that the tunic phagocytes are likely to be the major effector cells in the allorejection reaction. We also propose that the tunic phagocytes are not only the effector cells in the allorejection reaction but also bear the sites of allorecognition.
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Affiliation(s)
- Teruhisa Ishii
- Division of Biology, Department of Natural and Environmental Sciences, Faculty of Education and Human Studies, Akita University, Akita 010-8502, Japan.
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42
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Hecht J, Stricker S, Wiecha U, Stiege A, Panopoulou G, Podsiadlowski L, Poustka AJ, Dieterich C, Ehrich S, Suvorova J, Mundlos S, Seitz V. Evolution of a core gene network for skeletogenesis in chordates. PLoS Genet 2008; 4:e1000025. [PMID: 18369444 PMCID: PMC2265531 DOI: 10.1371/journal.pgen.1000025] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2007] [Accepted: 02/07/2008] [Indexed: 01/27/2023] Open
Abstract
The skeleton is one of the most important features for the reconstruction of vertebrate phylogeny but few data are available to understand its molecular origin. In mammals the Runt genes are central regulators of skeletogenesis. Runx2 was shown to be essential for osteoblast differentiation, tooth development, and bone formation. Both Runx2 and Runx3 are essential for chondrocyte maturation. Furthermore, Runx2 directly regulates Indian hedgehog expression, a master coordinator of skeletal development. To clarify the correlation of Runt gene evolution and the emergence of cartilage and bone in vertebrates, we cloned the Runt genes from hagfish as representative of jawless fish (MgRunxA, MgRunxB) and from dogfish as representative of jawed cartilaginous fish (ScRunx1-3). According to our phylogenetic reconstruction the stem species of chordates harboured a single Runt gene and thereafter Runt locus duplications occurred during early vertebrate evolution. All newly isolated Runt genes were expressed in cartilage according to quantitative PCR. In situ hybridisation confirmed high MgRunxA expression in hard cartilage of hagfish. In dogfish ScRunx2 and ScRunx3 were expressed in embryonal cartilage whereas all three Runt genes were detected in teeth and placoid scales. In cephalochordates (lancelets) Runt, Hedgehog and SoxE were strongly expressed in the gill bars and expression of Runt and Hedgehog was found in endo- as well as ectodermal cells. Furthermore we demonstrate that the lancelet Runt protein binds to Runt binding sites in the lancelet Hedgehog promoter and regulates its activity. Together, these results suggest that Runt and Hedgehog were part of a core gene network for cartilage formation, which was already active in the gill bars of the common ancestor of cephalochordates and vertebrates and diversified after Runt duplications had occurred during vertebrate evolution. The similarities in expression patterns of Runt genes support the view that teeth and placoid scales evolved from a homologous developmental module.
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Affiliation(s)
- Jochen Hecht
- BCRT, Universitätsmedizin Charité, Berlin, Germany
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Sigmar Stricker
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Ulrike Wiecha
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Asita Stiege
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | | | - Lars Podsiadlowski
- Department of Animal Systematics and Evolution, Free University, Berlin, Germany
| | | | - Christoph Dieterich
- MPI for Developmental Biology Department 4 - Evolutionary Biology, Tübingen, Germany
| | | | - Julia Suvorova
- Max Planck Institute for Molecular Genetics, Berlin, Germany
| | - Stefan Mundlos
- BCRT, Universitätsmedizin Charité, Berlin, Germany
- Max Planck Institute for Molecular Genetics, Berlin, Germany
- Institute for Medical Genetics, Charité, Universitätsmedizin Berlin, Berlin, Germany
| | - Volkhard Seitz
- Max Planck Institute for Molecular Genetics, Berlin, Germany
- * E-mail:
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43
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Søviknes AM, Glover JC. Continued growth and cell proliferation into adulthood in the notochord of the appendicularian Oikopleura dioica. Biol Bull 2008; 214:17-28. [PMID: 18258772 DOI: 10.2307/25066656] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The appendicularian urochordate Oikopleura dioica retains a free-swimming chordate body plan throughout life, in contrast to ascidian urochordates, whose metamorphosis to a sessile adult form involves the loss of chordate structures such as the notochord and dorsal nerve cord. Development to adult stages in Oikopleura involves a lengthening of the tail and notochord and an elaboration of the repertoire of tail movements. To investigate the cellular basis for this lengthening, we have used confocal microscopy and BrdU labeling to examine the development of the Oikopleura notochord from hatching through adult stages. We show that as the notochord undergoes the typical urochordate transition from a stacked row of cells to a tubular structure, cell number begins to increase. Addition of new notochord cells continues into adulthood, multiplying the larval complement of 20 cells by about 8-fold by the third day of life. In parallel, the notochord lengthens by about 4-fold. BrdU incorporation and a cell-cycle marker confirm that notochord cells continue to proliferate well into adulthood. The extensive postlarval proliferation of notochord cells, together with their arrangement in four circumferentially distributed longitudinal rows, presumably provides the Oikopleura tail with the necessary mechanical support for the complex movements exhibited at adult stages.
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Affiliation(s)
- Anne Mette Søviknes
- Sars International Centre for Marine Molecular Biology, University of Bergen, Bergen High Technology Centre, Thormøhlensgt. 55, N-5008 Bergen, Norway
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44
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Abstract
Although ascidians are conspicuous members of the fouling community not much is known regarding their recruitment patterns in coral reefs. A 1-year study was carried out along the Red Sea coast of Israel to examine the effects of season and spatial distribution on ascidian recruitment to artificial marine structures. In general, autumn and spring were characterized by higher coverage with a significantly higher percentage of cover of Didemnum granulatum in autumn and higher numbers of Herdmania momus in spring. These species contributed the most to similarity between treatments consequently setting the pattern for each group (colonial and solitary). Halocynthia spinosa had significantly higher numbers during winter and Phallusia nigra was absent in spring and winter. H. momus showed a preference for horizontal surfaces. P. nigra and Ascidia cannelata showed a preference for floating units. It is concluded that the ascidian recruitment patterns are species-specific and vary between seasons, orientation and position on the substrata and in the water column.
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Affiliation(s)
- Noa Shenkar
- Department of Zoology, The George S. Wise Faculty of Life Sciences, Tel-Aviv University, Tel Aviv, Israel.
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Troedsson C, Ganot P, Bouquet JM, Aksnes DL, Thompson EM. Endostyle cell recruitment as a frame of reference for development and growth in the Urochordate Oikopleura dioica. Biol Bull 2007; 213:325-334. [PMID: 18083972 DOI: 10.2307/25066650] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
In models of growth and life history, and in molecular and cell biology, there is a need for more accurate frames of reference to characterize developmental progression. In Caenorhabditis elegans, complete fate maps of cell lineage provide such a standard of reference. To be more widely applicable, reference frames should be easier to measure while still providing strong predictive capacity. Towards this aim, we have analyzed growth of the endostyle in the appendicularian Oikopleura dioica at the cellular level, and measured its response to temperature and food availability. Specifically, we test the hypothesis that age of a specific developmental stage in O. dioica can be predicted from the number of endostyle cells and temperature. We show that the endostyle grows by recruiting cells from the posterior tip into the lateral arms of the organ in an anterior-posterior orientation and that the rate of increase in lateral arm endostyle cells is temperature-dependent but unresponsive to nutritional intake. Endostyle cells therefore serve as an accurate and easily measured marker to describe developmental progression. Conceptually, such a method of characterizing developmental progression should help bridge life-history events and molecular mechanisms throughout organismal aging, facilitating cross-disciplinary understanding by providing a common experimental framework.
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Affiliation(s)
- Christofer Troedsson
- Sars Centre for Marine Molecular Biology, Bergen High Technology Centre, University of Bergen, Thormøhlensgate 55, N-5008 Bergen, Norway
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Rosner A, Paz G, Rinkevich B. Divergent roles of the DEAD-box protein BS-PL10, the urochordate homologue of human DDX3 and DDX3Y proteins, in colony astogeny and ontogeny. Dev Dyn 2007; 235:1508-21. [PMID: 16518819 DOI: 10.1002/dvdy.20728] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Proteins of the highly conserved PL-10 (Ded1P) subfamily of DEAD-box family, participate in a wide variety of biological functions. However, the entire spectrum of their functions in both vertebrates and invertebrates is still unknown. Here, we isolated the Botryllus schlosseri (Urochordata) homologue, BS-PL10, revealing its distributions and functions in ontogeny and colony astogeny. In botryllid ascidians, the colony grows by increasing the number of modular units (each called a zooid) through a whole colony synchronized and weekly cyclical astogenic budding process (blastogenesis). At the level of the colony, both BS-PL10 mRNA and its protein (78 kDa) fluctuate in a weekly pattern that corresponds with the animal's blastogenic cycle, increasing from blastogenic stage A to blastogenic stage D. At the organ/module level, a sharp decline is revealed. Primary and secondary developing buds express high levels of BS-PL10 mRNA and protein at all blastogeneic stages. These levels are reduced four to nine times in the new set of functional zooids. This portrait of colony astogeny differed from its ontogeny. Oocytes and sperm cells express high levels of BS-PL10 protein only at early stages of development. Young embryos reveal background levels with increased expressions in some organs at more developed stages. Results reveal that higher levels of BS-PL10 mRNA and protein are characteristic to multipotent soma and germ cells, but patterns deviate between two populations of differentiating stem cells, the stem cells involved in weekly blastogenesis and stem cells involved in embryogenesis. Two types of experimental manipulations, zooidectomy and siRNA assays, have confirmed the importance of BS-PL10 for cell differentiation and organogenesis. BS-PL10 (phylogenetically matching the animal's position in the evolutionary tree), is the only member of this subfamily in B. schlosseri, featuring a wide range of biological activities, some of which represent pivotal roles. The surprising weekly cyclical expression and the participation in cell differentiation posit this molecule as a model system for studying PL10 protein subfamily.
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Affiliation(s)
- Amalia Rosner
- National Institute of Oceanography, Israel Oceanographic & Limnological Research, Tel Shikmona, Haifa, Israel.
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Jeffery WR. Chordate ancestry of the neural crest: New insights from ascidians. Semin Cell Dev Biol 2007; 18:481-91. [PMID: 17509911 DOI: 10.1016/j.semcdb.2007.04.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 01/31/2007] [Accepted: 04/10/2007] [Indexed: 11/29/2022]
Abstract
This article reviews new insights from ascidians on the ancestry of vertebrate neural crest (NC) cells. Ascidians have neural crest-like cells (NCLC), which migrate from the dorsal midline, express some of the typical NC markers, and develop into body pigment cells. These characters suggest that primordial NC cells were already present in the common ancestor of the vertebrates and urochordates, which have been recently inferred as sister groups. The primitive role of NCLC may have been in pigment cell dispersal and development. Later, additional functions may have appeared in the vertebrate lineage, resulting in the evolution of definitive NC cells.
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Affiliation(s)
- William R Jeffery
- Department of Biology, University of Maryland, College Park, MD 20742, USA.
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48
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Abstract
Although phylogenetically related to vertebrates, invertebrate chordate tunicates possess an open circulatory system, with blood flowing in lacunae among organs. However, the colonial circulatory system (CCS) of the ascidian Botryllus schlosseri runs in the common tunic and forms an anastomized network of vessels, defined by simple epithelium, connected to the open circulatory system of the zooids. The CCS originates from epidermal evagination, grows, and increases its network accompanying colony propagation. New vessels are formed by means of mechanisms of tubular sprouting which, in their morphogenesis and molecular regulation, are very similar to those occurring in other metazoans, particularly during vertebrate angiogenesis. From the apex of new vessels, epithelial cells detach and migrate into the tunic, while exploring filopodia extend toward the tunic and possibly guide vessel growth. Immunohistology showed that growth factors fibroblast growth factor-2 and vascular endothelial growth factor and the receptor vascular endothelial growth factor receptor-1 participate in sprouting, associated with cell proliferation. As in vertebrates, these factors may regulate cell migration, proliferation, sprouting, and tube formation. Our data indicate that similar, conserved signals were co-opted in the sprouting processes of two nonhomologous circulatory systems, that of ascidian CCS, and vertebrate circulatory systems, by recruitment of the same signaling pathway.
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Affiliation(s)
- Fabio Gasparini
- Dipartimento di Biologia, Università degli Studi di Padova, Padova, Italy.
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49
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Joly JS, Osório J, Alunni A, Auger H, Kano S, Rétaux S. Windows of the brain: Towards a developmental biology of circumventricular and other neurohemal organs. Semin Cell Dev Biol 2007; 18:512-24. [PMID: 17631396 DOI: 10.1016/j.semcdb.2007.06.001] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2007] [Accepted: 06/05/2007] [Indexed: 11/25/2022]
Abstract
We review the anatomical and functional features of circumventricular organs in vertebrates and their homologous neurohemal organs in invertebrates. Focusing on cyclostomes (lamprey) and urochordates (ascidians), we discuss the evolutionary origin of these organs as a function of their cell type specification and morphogenesis.
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Affiliation(s)
- Jean-Stéphane Joly
- U1126/INRA Morphogenèse du système nerveux des chordés group, DEPSN, UPR2197, Institut Fessard, CNRS, 1 Avenue de la Terrasse, 91198 GIF SUR YVETTE, France.
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50
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Gyoja F, Satou Y, Shin-i T, Kohara Y, Swalla BJ, Satoh N. Analysis of large scale expression sequenced tags (ESTs) from the anural ascidian, Molgula tectiformis. Dev Biol 2007; 307:460-82. [PMID: 17540363 DOI: 10.1016/j.ydbio.2007.03.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2006] [Revised: 03/19/2007] [Accepted: 03/23/2007] [Indexed: 11/27/2022]
Abstract
Anural ascidians show embryogenesis during which tail formation does not take place. This mode of development is a derived character acquired several times independently in ascidian evolution. We identified approximately 20,000 each ESTs (i. e. 10,000 clones each were sequenced from both 5' and 3' ends) of adult gonads, cleaving-embryos, gastrulae/neurulae, embryos before hatching, and hatched larvae of the anural ascidian Molgula tectiformis, in order to comprehensively investigate the molecular mechanism of tailless evolution. Analyses of these ESTs showed that in this species, (1) the expression of embryonic/larval muscle structural genes which are expressed abundantly during embryogenesis of the urodele ascidian Ciona intestinalis, is suppressed; (2) genes that encode proteins with no similarity to known proteins of other organisms are abundantly expressed; (3) genes that show similarity with those up-regulated at metamorphosis in urodele ascidians are up-regulated within several hours after hatching; and (4) 15 of 35 putative orthologues of the downstream components of Brachyury, a key transcription factor for ascidian notochord formation, were found in the ESTs, even though differentiation of notochord is suppressed in this species. We discuss these remarkable results that allow insight into the molecular mechanism(s) responsible for the anural mode of ascidian development.
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Affiliation(s)
- Fuki Gyoja
- Department of Zoology, Graduate School of Science, Kyoto University, Kyoto 606-8502, Japan.
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