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Nakamura M, Oguchi K, Sato DS, Kato S, Okanishi M, Hayashi Y, Aguado MT, Miura T. Morphological, histological and gene-expression analyses on stolonization in the Japanese Green Syllid, Megasyllis nipponica (Annelida, Syllidae). Sci Rep 2023; 13:19419. [PMID: 37993494 PMCID: PMC10665476 DOI: 10.1038/s41598-023-46358-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2023] [Accepted: 10/31/2023] [Indexed: 11/24/2023] Open
Abstract
Benthic annelids belonging to the family Syllidae (Annelida, Errantia, Phyllodocida) exhibit a unique reproduction mode called "schizogamy" or "stolonization", in which the posterior body part filled with gametes detaches from the original body, as a reproductive unit (stolon) that autonomously swims and spawns. In this study, morphological and histological observations on the developmental processes during stolonization were carried out in Megasyllis nipponica. Results suggest that the stolon formation started with maturation of gonads, followed by the formation of a head ganglion in the anteriormost segment of the developing stolon. Then, the detailed stolon-specific structures such as stolon eyes and notochaetae were formed. Furthermore, expression profiles of genes involved in the anterior-posterior identity (Hox genes), head determination, germ-line, and hormone regulation were compared between anterior and posterior body parts during the stolonization process. The results reveal that, in the posterior body part, genes for gonadal development were up-regulated, followed by hormone-related genes and head-determination genes. Unexpectedly, Hox genes known to identify body parts along the anterior-posterior axis showed no significant temporal expression changes. These findings suggest that during stolonization, gonad development induces the head formation of a stolon, without up-regulation of anterior Hox genes.
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Affiliation(s)
- Mayuko Nakamura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan
| | - Kohei Oguchi
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan
| | - Daisuke S Sato
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan
| | - Sumika Kato
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo, Tokyo, 113-0033, Japan
| | - Masanori Okanishi
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan
- Faculty of Human Environmental Studies, Hiroshima Shudo University, Ozuka-Higashi, Asaminami, Hiroshima, 731-3195, Japan
| | - Yoshinobu Hayashi
- Department of Biology, Keio University, Hiyoshi, Yokohama, 223-8521, Japan
| | - M Teresa Aguado
- Animal Evolution and Biodiversity, Georg-August-Universität Göttingen, 37073, Göttingen, Germany
| | - Toru Miura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa, 238-0225, Japan.
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2
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Engel N, Aguado MT, Maraun M. Trophic ecology of three marine polychaete species: Evidence from laboratory experiments using stable isotope ( 15N, 13C), fatty acid (NLFA) analyses, and C and N stoichiometry. MARINE ENVIRONMENTAL RESEARCH 2023; 185:105878. [PMID: 36652888 DOI: 10.1016/j.marenvres.2023.105878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2022] [Revised: 12/23/2022] [Accepted: 01/10/2023] [Indexed: 06/17/2023]
Abstract
Marine polychaetes are a highly diverse taxon with a large variety of different feeding modes. A proper identification of the different diets of polychaete species and their trophic position in the food web is crucial for understanding their interactions in marine ecosystems as well as marine community dynamics. Since gut content analyses and feeding experiments are difficult to conduct in marine habitats, other methods using biochemical tracers may contribute to a better understanding of the trophic ecology of marine polychaetes. Here, we conducted laboratory experiments and used a combination of stable isotope (13C, 15N) and neutral lipid fatty acid (NLFA) analyses, as well as C and N stoichiometry to determine the feeding habits of widely distributed marine polychaete species, such as Eurythoe complanata, Platynereis massiliensis, and Syllis malaquini. Additionally, the impact of starvation on the stable isotope signatures was analyzed. Our data show that the trophic ecology of the three species differs from each other. Stable isotope and fatty acid analyses indicate that (a) E. complanata is mainly feeding on algae, cyanobacteria and to a lesser extent on fungi, that (b) S. malaquini is mainly feeding on algae and bacteria and that (c) P. massiliensis is mainly feeding on algae, especially diatoms. An analysis of the C:N ratio of the respective annelid species and their potential food sources corroborated these results. The combination of stable isotope signatures, fatty acid markers and stoichiometry of carbon and nitrogen is a useful tool to identify the diet and trophic position of marine polychaete species and provides more results about their feeding habits and their position in marine food webs.
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Affiliation(s)
- Nele Engel
- Dep. Animal Evolution and Biodiversity, JFB Institute for Zoology and Anthropology, Georg-August-University Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany.
| | - M Teresa Aguado
- Dep. Animal Evolution and Biodiversity, JFB Institute for Zoology and Anthropology, Georg-August-University Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
| | - Mark Maraun
- Dep. Animal Ecology, JFB Institute of Zoology and Anthropology, Georg-August-University Göttingen, Untere Karspüle 2, 37073, Göttingen, Germany
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3
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Hayashi Y, Oguchi K, Nakamura M, Koshikawa S, Miura T. Construction of a massive genetic resource by transcriptome sequencing and genetic characterization of Megasyllis nipponica (Annelida: Syllidae). Genes Genet Syst 2022; 97:153-166. [PMID: 36070927 DOI: 10.1266/ggs.21-00137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Understanding the processes and consequences of the morphological diversity of organisms is one of the major goals of evolutionary biology. Studies on the evolution of developmental mechanisms of morphologies, or evo-devo, have been extensively conducted in many taxa and have revealed many interesting phenomena at the molecular level. However, many other taxa exhibiting intriguing morphological diversity remain unexplored in the field of evo-devo. Although the annelid family Syllidae shows spectacular diversity in morphological development associated with reproduction, its evo-devo study, especially on molecular development, has progressed slowly. In this study, we focused on Megasyllis nipponica as a new model species for evo-devo in syllids and performed transcriptome sequencing to develop a massive genetic resource, which will be useful for future molecular studies. From the transcriptome data, we identified candidate genes that are likely involved in morphogenesis, including genes involved in hormone regulation, sex determination and appendage development. Furthermore, a computational analysis of the transcriptome sequence data indicated the occurrence of DNA methylation in coding regions of the M. nipponica genome. In addition, flow cytometry analysis showed that the genome size of M. nipponica was approximately 524 megabases. These results facilitate the study of morphogenesis in molecular terms and contribute to our understanding of the morphological diversity in syllids.
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Affiliation(s)
| | - Kohei Oguchi
- Misaki Marine Biological Station, School of Science, The University of Tokyo.,National Institute of Advanced Industrial Science and Technology (AIST)
| | - Mayuko Nakamura
- Misaki Marine Biological Station, School of Science, The University of Tokyo
| | - Shigeyuki Koshikawa
- Faculty of Environmental Earth Science, Hokkaido University.,Graduate School of Environmental Science, Hokkaido University
| | - Toru Miura
- Misaki Marine Biological Station, School of Science, The University of Tokyo
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4
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Ribeiro RP, Egger B, Ponz-Segrelles G, Aguado MT. Cellular proliferation dynamics during regeneration in Syllis malaquini (Syllidae, Annelida). Front Zool 2021; 18:27. [PMID: 34044865 PMCID: PMC8161976 DOI: 10.1186/s12983-021-00396-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Accepted: 02/28/2021] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND In syllids (Annelida, Syllidae), the regenerative blastema was subject of many studies in the mid and late XXth century. This work on syllid regeneration showed that the blastema is developed by a process of dedifferentiation of cells near the wound, followed by their proliferation and redifferentiation (cells differentiate to the original cell type) or, in some specific cases, transdifferentiation (cells differentiate to a cell type different from the original). Up to date, participation of stem cells or pre-existing proliferative cells in the blastema development has never been observed in syllids. This study provides the first comprehensive description of Syllis malaquini's regenerative capacity, including data on the cellular proliferation dynamics by using an EdU/BrdU labelling approach, in order to trace proliferative cells (S-phase cells) present before and after operation. RESULTS Syllis malaquini can restore the anterior and posterior body from different cutting levels under experimental conditions, even from midbody fragments. Our results on cellular proliferation showed that S-phase cells present in the body before bisection do not significantly contribute to blastema development. However, in some specimens cut at the level of the proventricle, cells in S-phase located in the digestive tube before bisection participated in regeneration. Also, our results showed that nucleus shape allows to distinguish different types of blastemal cells as forming specific tissues. Additionally, simultaneous and sequential addition of segments seem to occur in anterior regeneration, while only sequential addition was observed in posterior regeneration. Remarkably, in contrast with previous studies in syllids, sexual reproduction was not induced during anterior regeneration of amputees lacking the proventricle, a foregut organ widely known to be involved in the stolonization control. CONCLUSIONS Our findings led us to consider that although dedifferentiation and redifferentiation might be more common, proliferative cells present before injury can be involved in regenerative processes in syllids, at least in some cases. Also, we provide data for comparative studies on resegmentation as a process that differs between anterior and posterior regeneration; and on the controversial role of the proventricle in the reproduction of different syllid lineages.
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Affiliation(s)
- Rannyele Passos Ribeiro
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain.
| | - Bernhard Egger
- Institute of Zoology, University of Innsbruck, Innsbruck, Austria
| | | | - M Teresa Aguado
- Animal Evolution & Biodiversity, Georg-August-Universität Göttingen, Göttingen, Germany.
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Ponz-Segrelles G, Glasby CJ, Helm C, Beckers P, Hammel JU, Ribeiro RP, Aguado MT. Integrative anatomical study of the branched annelid Ramisyllis multicaudata (Annelida, Syllidae). J Morphol 2021; 282:900-916. [PMID: 33813762 DOI: 10.1002/jmor.21356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/26/2021] [Accepted: 03/30/2021] [Indexed: 01/14/2023]
Abstract
The sponge-dwelling Syllidae Ramisyllis multicaudata and Syllis ramosa are the only annelid species for which a branched body with one head and multiple posterior ends is known. In these species, the head is located deep within the sponge, and the branches extend through the canal system of their host. The morphology of these creatures has captivated annelid biologists since they were first discovered in the late XIXth century, and their external characteristics have been well documented. However, how their branched bodies fit within their symbiotic host sponges and how branches translate into internal anatomy has not been documented before. These features are crucially relevant for understanding the body of these animals, and therefore, the aim of this study was to investigate these aspects. In order to assess these questions, live observation, as wells as histology, immunohistochemistry, micro-computed tomography, and transmission electron microscopy techniques were used on specimens of R. multicaudata. By using these techniques, we show that the complex body of R. multicaudata specimens extends greatly through the canal system of their host sponges. We demonstrate that iterative external bifurcation of the body is accompanied by the bifurcation of the longitudinal organ systems that are characteristic of annelids. Additionally, we also highlight that the bifurcation process leaves an unmistakable fingerprint in the form of newly-described "muscle bridges." These structures theoretically allow one to distinguish original and derived branches at each bifurcation. Last, we characterize some of the internal anatomical features of the stolons (reproductive units) of R. multicaudata, particularly their nervous system. Here, we provide the first study of the internal anatomy of a branched annelid. This information is not only crucial to deepen our understanding of these animals and their biology, but it will also be key to inform future studies that try to explain how this morphology evolved.
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Affiliation(s)
| | - Christopher J Glasby
- Natural Sciences Department, Museum and Art Gallery of the Northern Territory, Darwin, Northern Territory, Australia
| | - Conrad Helm
- Animal Evolution & Biodiversity, Georg-August-Universität Göttingen, Göttingen, Germany
| | - Patrick Beckers
- Institute of Evolutionary Biology and Ecology, University of Bonn, Bonn, Germany
| | - Jörg U Hammel
- Institute of Materials Research, Helmholtz-Zentrum Geesthacht, Geesthacht, Germany
| | - Rannyele P Ribeiro
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Madrid, Spain
| | - M Teresa Aguado
- Animal Evolution & Biodiversity, Georg-August-Universität Göttingen, Göttingen, Germany
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6
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Ponz-Segrelles G, Ribeiro RP, Bleidorn C, Aguado Molina MT. Sex-specific gene expression differences in reproducing Syllis prolifera and Nudisyllis pulligera (Annelida, Syllidae). Mar Genomics 2020; 54:100772. [DOI: 10.1016/j.margen.2020.100772] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2019] [Revised: 03/02/2020] [Accepted: 04/02/2020] [Indexed: 01/22/2023]
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7
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Miura T, Oguchi K, Nakamura M, Jimi N, Miura S, Hayashi Y, Koshikawa S, Aguado MT. Life Cycle of the Japanese Green Syllid, Megasyllis nipponica (Annelida: Syllidae): Field Collection and Establishment of Rearing System. Zoolog Sci 2019; 36:372-379. [PMID: 33319960 DOI: 10.2108/zs190058] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2019] [Accepted: 05/05/2019] [Indexed: 11/17/2022]
Abstract
Some polychaete species in the family Syllidae exhibit distinctive life cycles, in which a posterior part of the body of an individual detaches as a reproductive individual called a "stolon". This type of reproductive mode is known as stolonization or schizogamy. Although a number of observations have been reported, and techniques using molecular markers have recently been applied to characterize this phenomenon, little is known about the developmental and physiological mechanisms underlying stolonization. In the present study, Megasyllis nipponica, a common syllid species distributed throughout Japan, is proposed as a model to reveal the developmental and physiological mechanism of stolonization, and the rearing system to maintain it in laboratory conditions is described. This species was repeatedly sampled around Hokkaido, where more dense populations were found from August to October. The animals were maintained in the laboratory under stable long-day condition (20°C, 16L:8D), and fed mainly with spinach powder. Stolonization processes, spawning, embryonic and postembryonic development were observed and documented, and the required period of time for each developmental stage was recorded. The complete generation time was around two months under the rearing condition. The information provided is valuable to maintain this and other syllid species in the laboratory, and hence contributes to the establishment of new evolutionary and developmental research lines in this group of annelids.
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Affiliation(s)
- Toru Miura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan, .,Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Kohei Oguchi
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan.,Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Mayuko Nakamura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan
| | - Naoto Jimi
- Bioscience Group, National Institute of Polar Research, Tachikawa, Tokyo 190-0014, Japan
| | - Sakiko Miura
- Misaki Marine Biological Station, School of Science, The University of Tokyo, Misaki, Miura, Kanagawa 238-0225, Japan.,Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - Yoshinobu Hayashi
- Department of Biology, Keio University, Yokohama, Kanagawa 223-8521, Japan
| | - Shigeyuki Koshikawa
- Faculty of Environmental Earth Science, Hokkaido University, Sapporo, Hokkaido 060-0810, Japan
| | - M Teresa Aguado
- Animal Evolution and Biodiversity, Johann-Friedrich-Blumenbach Institute for Zoology and Anthropology, Georg-August-Universität Göttingen, Göttingen, Germany.,Centro de Investigación en Biodiversidad y Cambio Global (CIBC-UAM), Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049, Madrid, Spain
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Parapar J, Caramelo C, Candás M, Cunha-Veira X, Moreira J. An integrative approach to the anatomy of Syllis gracilis Grube, 1840 (Annelida) using micro-computed X-ray tomography. PeerJ 2019; 7:e7251. [PMID: 31328035 PMCID: PMC6622173 DOI: 10.7717/peerj.7251] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 05/13/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND The overall anatomy of the genus Syllis (Annelida: Syllidae) has been largely studied; however, an integrative approach considering different anatomical techniques has never been considered. Here, we use micro-computed X-ray tomography (micro-CT) to examine the internal anatomy of Syllis gracilis Grube, 1840, along with other widely available techniques. METHODS We studied the anatomy of the marine annelid S. gracilis through an integrative approach, including micro-CT along with stereo and light compound microscopy (STM, LCM), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and histological sectioning (HIS). In this manner, we evaluated the applicability of micro-CT for the examination of annelid anatomy by testing whether the images obtained make it possible to visualize the main body structures, in comparison with other current techniques, of the various elements of its internal anatomy. RESULTS Overall external and internal body elements are clearly shown by the integrative use of all techniques, thus overcoming the limitations of each when studied separately.Any given method shows disparate results, depending on the body part considered. For instance, micro-CT provided good images of the external anatomy, including relevant characters such as the shape, length and number of articles of dorsal parapodial cirri. However, it is especially useful for the examination of internal anatomy, thus allowing for 3D visualization of the natural spatial arrangement of the different organs. The features best visualized are those of higher tissue density (i.e., body musculature, anterior parts of the digestive tract), particularly in 3D images of unstained specimens, whereas less electrodense tissues (i.e., the peritoneal lining of septa and nervous system) are less clearly visualized. The use of iodine stain with micro-CT has shown advantages against non-staining for the adequate observation of delicate elements of low density, such as the segmental organs, the connective between the ganglia, the ventral nerve cord and segmental nerves. DISCUSSION Main external anatomical elements of S. gracilis are well shown with micro-CT, but images show lesser optical resolution and contrast when compared to micrographs provided by SEM and CLSM, especially for fine structural features of chaetae. Comparison of micro-CT and HIS images revealed the utility and reliability of the former to show the presence, shape and spatial disposition of most internal body organs; the resolution of micro-CT images at a cellular level is, however, much lower than that of HIS, which makes both techniques complementary.
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Affiliation(s)
- Julio Parapar
- Departamento de Bioloxía, Universidade da Coruña, A Coruña, Spain
| | - Carlos Caramelo
- Departamento de Bioloxía, Universidade da Coruña, A Coruña, Spain
| | - María Candás
- Estación de Bioloxía Mariña da Graña, Universidade de Santiago de Compostela, Ferrol, Spain
| | - Xela Cunha-Veira
- Estación de Bioloxía Mariña da Graña, Universidade de Santiago de Compostela, Ferrol, Spain
| | - Juan Moreira
- Departamento de Biología, Universidad Autónoma de Madrid, Madrid, Spain
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Kobayashi G, Goto R, Takano T, Kojima S. Molecular phylogeny of Maldanidae (Annelida): Multiple losses of tube-capping plates and evolutionary shifts in habitat depth. Mol Phylogenet Evol 2018; 127:332-344. [DOI: 10.1016/j.ympev.2018.04.036] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 04/16/2018] [Accepted: 04/23/2018] [Indexed: 11/27/2022]
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10
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Ponz‐Segrelles G, Bleidorn C, Aguado MT. Expression of
vasa
,
piwi
, and
nanos
during gametogenesis in
Typosyllis antoni
(Annelida, Syllidae). Evol Dev 2018; 20:132-145. [DOI: 10.1111/ede.12263] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Guillermo Ponz‐Segrelles
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblancoMadridSpain
| | - Christoph Bleidorn
- Animal Evolution and BiodiversityGeorg‐August‐University GöttingenGöttingenGermany
| | - M. Teresa Aguado
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblancoMadridSpain
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Ribeiro RP, Bleidorn C, Aguado MT. Regeneration mechanisms in Syllidae (Annelida). REGENERATION (OXFORD, ENGLAND) 2018; 5:26-42. [PMID: 29721325 PMCID: PMC5911452 DOI: 10.1002/reg2.98] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Revised: 02/26/2018] [Accepted: 02/27/2018] [Indexed: 12/16/2022]
Abstract
Syllidae is one of the most species-rich groups within Annelida, with a wide variety of reproductive modes and different regenerative processes. Syllids have striking ability to regenerate their body anteriorly and posteriorly, which in many species is redeployed during sexual (schizogamy) and asexual (fission) reproduction. This review summarizes the available data on regeneration in syllids, covering descriptions of regenerative mechanisms in different species as well as regeneration in relation to reproductive modes. Our survey shows that posterior regeneration is widely distributed in syllids, whereas anterior regeneration is limited in most of the species, excepting those reproducing by fission. The latter reproductive mode is well known for a few species belonging to Autolytinae, Eusyllinae, and Syllinae. Patterns of fission areas have been studied in these animals. Deviations of the regular regeneration pattern or aberrant forms such as bifurcated animals or individuals with multiple heads have been reported for several species. Some of these aberrations show a deviation of the bilateral symmetry and antero-posterior axis, which, interestingly, can also be observed in the regular branching body pattern of some species of syllids.
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Affiliation(s)
- Rannyele P. Ribeiro
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblanco28049MadridSpain
| | - Christoph Bleidorn
- Animal Evolution and BiodiversityGeorg‐August‐Universität Göttingen37073 GöttingenGermany
- German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig04103 LeipzigGermany
| | - M. Teresa Aguado
- Departamento de BiologíaFacultad de CienciasUniversidad Autónoma de MadridCantoblanco28049MadridSpain
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12
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13
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Aguado MT, Richter S, Sontowski R, Golombek A, Struck TH, Bleidorn C. Syllidae mitochondrial gene order is unusually variable for Annelida. Gene 2016; 594:89-96. [DOI: 10.1016/j.gene.2016.08.050] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 08/21/2016] [Accepted: 08/29/2016] [Indexed: 01/16/2023]
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14
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Weidhase M, Beckers P, Bleidorn C, Aguado MT. On the role of the proventricle region in reproduction and regeneration in Typosyllis antoni (Annelida: Syllidae). BMC Evol Biol 2016; 16:196. [PMID: 27716025 PMCID: PMC5050598 DOI: 10.1186/s12862-016-0770-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2016] [Accepted: 09/28/2016] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND Syllids are a species rich annelid family possessing remarkable regenerative ability, which is not only the response after traumatic injury, but also a key step during the life cycle of several syllid taxa. In these animals the posterior part of the body becomes an epitoke and is later detached as a distinct unit named stolon. Such a sexual reproductive mode is named schizogamy or stolonization. The prostomium and the proventricle, a modified foregut structure, have been proposed to have a control function during this process, though the concrete mechanisms behind it have never been elucidated. RESULTS By using different experimental set-ups, histology and immunohistochemistry combined with subsequent cLSM analyzes, we investigate and document the regeneration and stolonization in specimens of Typosyllis antoni that were amputated at different levels throughout the antero-posterior body axis. The removal of the anterior end including the proventricle implies an incomplete anterior regeneration as well as severe deviations from the usual reproductive pattern, i.e. accelerated stolonization, masculinization and the occurrence of aberrant stolons. The detailed anatomy of aberrant stolons is described. A histological study of the proventricle revealed no signs of glandular or secretory structures. The ventricle and the caeca are composed of glandular tissue but they are not involved in the reproductive and regenerative processes. CONCLUSIONS As in other investigated syllids, the proventricle region has a significant role during stolonization and reproduction processes in Typosyllis antoni. When the proventricle region is absent, anterior and posterior regeneration are considerably deviated from the general patterns. However, proventricle ultrastructure does not show any glandular component, thereby questioning a direct involvement of this organ itself in the control of reproduction and regeneration. Our findings offer a comprehensive starting point for further studies of regeneration and reproductive control in syllids as well as annelids in general.
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Affiliation(s)
- Michael Weidhase
- Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
| | - Patrick Beckers
- Zoology and Evolutionary Biology, Institute of Evolutionary Biology and Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn, An der Immenburg 1, D-53121 Bonn, Germany
| | - Christoph Bleidorn
- Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
- Museo Nacional de Ciencias Naturales, Spanish Research Council (CSIC), José Gutiérrez Abascal 2, 28006 Madrid, Spain
| | - M. Teresa Aguado
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
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Weidhase M, Bleidorn C, Beckers P, Helm C. Myoanatomy and anterior muscle regeneration of the firewormEurythoecf.complanata(Annelida: Amphinomidae). J Morphol 2015; 277:306-15. [DOI: 10.1002/jmor.20496] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2015] [Revised: 10/30/2015] [Accepted: 11/06/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Michael Weidhase
- Molecular Evolution & Animal Systematics; Institute of Biology, University of Leipzig; Talstraße 33 Leipzig D-04103 Germany
| | - Christoph Bleidorn
- Molecular Evolution & Animal Systematics; Institute of Biology, University of Leipzig; Talstraße 33 Leipzig D-04103 Germany
| | - Patrick Beckers
- Institute for Evolutionary Biology and Ecology, Rheinische Friedrich-Wilhelms-Universität Bonn; an Der Immenburg 1 Bonn 53121 Germany
| | - Conrad Helm
- Sars International Centre for Marine Molecular Biology, University of Bergen; Thormøhlensgt. 55 Bergen N-5008 Norway
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Aguado MT, Glasby CJ, Schroeder PC, Weigert A, Bleidorn C. The making of a branching annelid: an analysis of complete mitochondrial genome and ribosomal data of Ramisyllis multicaudata. Sci Rep 2015; 5:12072. [PMID: 26183383 PMCID: PMC4505326 DOI: 10.1038/srep12072] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 06/12/2015] [Indexed: 12/13/2022] Open
Abstract
Ramisyllis multicaudata is a member of Syllidae (Annelida, Errantia, Phyllodocida) with a remarkable branching body plan. Using a next-generation sequencing approach, the complete mitochondrial genomes of R. multicaudata and Trypanobia sp. are sequenced and analysed, representing the first ones from Syllidae. The gene order in these two syllids does not follow the order proposed as the putative ground pattern in Errantia. The phylogenetic relationships of R. multicaudata are discerned using a phylogenetic approach with the nuclear 18S and the mitochondrial 16S and cox1 genes. Ramisyllis multicaudata is the sister group of a clade containing Trypanobia species. Both genera, Ramisyllis and Trypanobia, together with Parahaplosyllis, Trypanosyllis, Eurysyllis, and Xenosyllis are located in a long branched clade. The long branches are explained by an accelerated mutational rate in the 18S rRNA gene. Using a phylogenetic backbone, we propose a scenario in which the postembryonic addition of segments that occurs in most syllids, their huge diversity of reproductive modes, and their ability to regenerate lost parts, in combination, have provided an evolutionary basis to develop a new branching body pattern as realised in Ramisyllis.
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Affiliation(s)
- M. Teresa Aguado
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain
| | - Christopher J. Glasby
- Museum and Art Gallery of the Northern Territory, GPO Box 4646, Darwin, N.T., Australia
| | - Paul C. Schroeder
- School of Biological Sciences, Washington State University, Pullman, Washington 99163-4236, USA
| | - Anne Weigert
- Molecular Evolution and Systematics of Animals, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
- Max Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, 04103 Leipzig, Germany
| | - Christoph Bleidorn
- Molecular Evolution and Systematics of Animals, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
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Aguado MT, Glasby CJ. Indo-Pacific Syllidae (Annelida, Phyllodocida) share an evolutionary history. SYST BIODIVERS 2015. [DOI: 10.1080/14772000.2014.992379] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Weidhase M, Helm C, Bleidorn C. Morphological investigations of posttraumatic regeneration in Timarete cf. punctata (Annelida: Cirratulidae). ZOOLOGICAL LETTERS 2015; 1:20. [PMID: 26605065 PMCID: PMC4657251 DOI: 10.1186/s40851-015-0023-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 06/23/2015] [Indexed: 05/10/2023]
Abstract
INTRODUCTION Annelids exhibit great regenerative abilities, which are mainly used after injury or during reproduction. These lophotrochozoans thus represent excellent models for regeneration research. However, detailed morphological studies concerning annelid musculature and nervous system redevelopment are limited to few taxa, and do not allow for broader comparisons and general conclusions regarding common patterns amongst annelids. RESULTS Using immunohistochemical staining combined with confocal laser scanning microscopy (cLSM), we investigated the redevelopment of body wall musculature and nervous system during anterior and posterior posttraumatic regeneration in Timarete cf. punctata. Both regeneration processes start with wound healing, blastema formation, and blastema patterning. In posterior regeneration, this leads to the development of a new pygidium and a segment addition zone (SAZ) anterior to this structure. New segments are subsequently added in a sequential fashion. Anterior regeneration in contrast shows the formation of a new prostomium and peristomium first, followed by the simultaneous redevelopment of three segments, and an additional three segments in sequential order. Anterior muscular regeneration shows an outgrowth of longitudinal musculature from the residual body wall musculature, while circular musculature develops independently within the blastema. During posterior regeneration, new musculature becomes visible when the new segments reached a certain age. Neuronal regeneration begins with neurite outgrowth from the old ventral nerve cord in both cases, which are later forming loop structures. In anterior regeneration, the brain redevelops at the anteriormost position of the loops. CONCLUSIONS Posterior regeneration recapitulates normal growth from a certain timepoint with serial segment development by a posterior segment addition zone. Anterior regeneration is more complex, showing similarities to larval development in matters of the order, in which prostomium, peristomium, and segments are generated. Furthermore, we demonstrate the usefulness of regeneration studies to investigate morphological structures and evolutionary processes.
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Affiliation(s)
- Michael Weidhase
- />Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
| | - Conrad Helm
- />Sars International Centre for Marine Molecular Biology, Thormøhlensgt. 55, N-5008 Bergen, Norway
| | - Christoph Bleidorn
- />Molecular Evolution & Animal Systematics, Institute of Biology, University of Leipzig, Talstraße 33, D-04103 Leipzig, Germany
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