1
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Kunselman LF, Seaver EC. Wnt/β-catenin signaling promotes posterior axial regeneration in non-regenerative tissue of the annelid Capitella teleta. Dev Biol 2025:S0012-1606(25)00140-X. [PMID: 40404078 DOI: 10.1016/j.ydbio.2025.05.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2025] [Revised: 04/24/2025] [Accepted: 05/17/2025] [Indexed: 05/24/2025]
Abstract
To rescue regeneration, the mechanisms underlying regeneration failure must be identified and overcome. In the annelid Capitella teleta, a transverse cut triggers asymmetric responses across the amputation plane: head fragments regenerate the tail, but tail fragments do not regenerate. We compare regeneration of head fragments (successful regeneration) to that of tail fragments (unsuccessful regeneration) using cell proliferation assays, immunolabeling, and in situ hybridization. Surprisingly, following amputation, a dynamic response of the nervous system occurs in the non-regenerating tail fragments of C. teleta that has not previously been described in annelids. Wnt/β-catenin signaling plays a conserved role in patterning the primary axis of some bilaterians during regeneration, but this role has never been demonstrated in annelids. Wnt/β-catenin pathway components are expressed in the blastema of head fragments but not at the cut site of tail fragments in C. teleta. Experimental activation of Wnt/β-catenin signaling following amputation of tail fragments (24 - 72 hr post amputation) induces expression of stem cell markers, increases cell division at the wound site, and produces differentiated muscle and hindgut. Furthermore, activation of Wnt/β-catenin signaling induces ectopic posterior identity at the amputation site, as it does in other bilaterians. Inhibition of Wnt/β-catenin signaling does not rescue head regeneration. Our results indicate that C. teleta tail fragments have latent regenerative potential that is activated by Wnt/β-catenin signaling. However, the incomplete regenerative response suggests that additional cell signaling pathways are required for this complex process. Comparing tissues with different regenerative abilities elucidates the mechanisms underlying regeneration regulation, thereby enabling the prospect of rescuing or increasing regeneration ability in regeneration-deficient tissues.
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Affiliation(s)
- Lauren F Kunselman
- Whitney Laboratory for Marine Bioscience, 5 N Ocean Shore Blvd, Saint Augustine, FL 32080, United States of America.
| | - Elaine C Seaver
- Whitney Laboratory for Marine Bioscience, 5 N Ocean Shore Blvd, Saint Augustine, FL 32080, United States of America.
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2
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Bodó K, Boros Á, da Costa CB, Tolnai G, Rumpler É, László Z, Nagyeri G, Németh P, Kille P, Molnár L, Engelmann P. A novel beta-catenin homologue from the earthworm Eisenia andrei: Identification and characterization during embryonic development, segment regeneration, and immune response. Int J Biol Macromol 2025; 306:141397. [PMID: 39988154 DOI: 10.1016/j.ijbiomac.2025.141397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2024] [Revised: 02/07/2025] [Accepted: 02/21/2025] [Indexed: 02/25/2025]
Abstract
Evolutionarily, Wnt/β-catenin signaling is well-conserved and supports several key cell-biological processes (e.g. adhesion and proliferation). Its crucial component, β-catenin, has been described in several organisms, however, its identification and characterization are notably lacking in annelid earthworms. Here, we report a novel β-catenin homologue from the earthworm Eisenia andrei, termed Ea-β-catenin. The full-length 3253 nt Ea-β-catenin mRNA includes an open reading frame of 2499 nt encoding a putative protein with 833 amino acid residues that comprise 11 classical armadillo-repeat regions. Phylogenetic analysis indicates that Ea-β-catenin shows strong homology with Lophotrochozoan β-catenins. Ubiquitous, but variable expressions of Ea-β-catenin were observed in distinct earthworm tissues. During embryogenesis, Ea-β-catenin mRNA gradually increased from the E1 to E4 developmental stages. Regeneration experiments revealed an inverse correlation between Ea-β-catenin mRNA levels and the rate of EdU+/PY489-β-catenin+ proliferating cells during the second week of the posterior blastema formation. In vitro exposures to poly(I:C) and zymosan significantly increased Ea-β-catenin mRNA levels, while small molecule Wnt-pathway modulators such as LiCl or iCRT14 increased or decreased Ea-β-catenin mRNA expression, and nuclear translocation of PY489-β-catenin, respectively. These novel results pave the way for follow-up studies aimed at characterizing additional members of the Wnt/β-catenin pathway that may be involved in embryonic and/or postembryonic development, as well as innate immunity in earthworms.
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Affiliation(s)
- Kornélia Bodó
- Department of Immunology and Biotechnology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - Ákos Boros
- Department of Medical Microbiology and Immunology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - Chayeen Brotzki da Costa
- Department of Immunology and Biotechnology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - Gréta Tolnai
- Department of Immunology and Biotechnology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - Éva Rumpler
- Department of Comparative Anatomy and Developmental Biology, Institute of Biology, Faculty of Sciences, University of Pécs, H-7624 Pécs, Hungary
| | - Zoltán László
- Department of Medical Microbiology and Immunology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - György Nagyeri
- Department of Neurobiology, Institute of Biology, Faculty of Sciences, University of Pécs, H-7624 Pécs, Hungary; Department of Animal Biotechnology, Institute of Genetics and Biotechnology, Hungarian University of Agriculture and Life Sciences, Szent-Györgyi Albert Street 4, H-2100 Gödöllő, Hungary
| | - Péter Németh
- Department of Immunology and Biotechnology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary
| | - Peter Kille
- School of Biosciences, Cardiff University, Cardiff CF10 3AX, UK
| | - László Molnár
- Ecophysiological and Ecotoxicological Research Group, HUN-REN, Balaton Limnological Research Institute, H-8237 Tihany, Hungary
| | - Péter Engelmann
- Department of Immunology and Biotechnology, Medical School, Clinical Center, University of Pécs, H-7624 Pécs, Hungary.
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3
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Mbogo I, Kawano C, Nakamura R, Tsuchiya Y, Villar-Briones A, Hirao Y, Yasuoka Y, Hayakawa E, Tomii K, Watanabe H. A transphyletic study of metazoan β-catenin protein complexes. ZOOLOGICAL LETTERS 2024; 10:20. [PMID: 39623505 PMCID: PMC11613877 DOI: 10.1186/s40851-024-00243-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/26/2024] [Accepted: 10/22/2024] [Indexed: 12/06/2024]
Abstract
Beta-catenin is essential for diverse biological processes, such as body axis determination and cell differentiation, during metazoan embryonic development. Beta-catenin is thought to exert such functions through complexes formed with various proteins. Although β-catenin complex proteins have been identified in several bilaterians, little is known about the structural and functional properties of β-catenin complexes in early metazoan evolution. In the present study, we performed a comparative analysis of β-catenin sequences in nonbilaterian lineages that diverged early in metazoan evolution. We also carried out transphyletic function experiments with β-catenin from nonbilaterian metazoans using developing Xenopus embryos, including secondary axis induction in embryos and proteomic analysis of β-catenin protein complexes. Comparative functional analysis of nonbilaterian β-catenins demonstrated sequence characteristics important for β-catenin functions, and the deep origin and evolutionary conservation of the cadherin-catenin complex. Proteins that co-immunoprecipitated with β-catenin included several proteins conserved among metazoans. These data provide new insights into the conserved repertoire of β-catenin complexes.
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Affiliation(s)
- Ivan Mbogo
- Evolutionary Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Sysmex Corporation, Ltd. 1-5-1, Chuo-ku, Kobe, 651-0073, Japan
| | - Chihiro Kawano
- Evolutionary Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Ryotaro Nakamura
- Evolutionary Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Yuko Tsuchiya
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan
| | - Alejandro Villar-Briones
- Instrumental Analysis Section, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Project Planning and Implementation Section, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Yoshitoshi Hirao
- Instrumental Analysis Section, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
| | - Yuuri Yasuoka
- Marine Genomics Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Laboratory for Comprehensive Genomic Analysis, RIKEN Center for Integrative Medical Sciences, Yokohama, Japan
| | - Eisuke Hayakawa
- Evolutionary Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan
- Department of Bioscience and Bioinformatics, Kyushu Institute of Technology, 680-4, Kawazu, Iizuka, 820-8502, Fukuoka, Japan
| | - Kentaro Tomii
- Artificial Intelligence Research Center, National Institute of Advanced Industrial Science and Technology (AIST), Tokyo, Japan
| | - Hiroshi Watanabe
- Evolutionary Neurobiology Unit, Okinawa Institute of Science and Technology Graduate University, Okinawa, Japan.
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4
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Vellutini BC, Martín-Durán JM, Børve A, Hejnol A. Combinatorial Wnt signaling landscape during brachiopod anteroposterior patterning. BMC Biol 2024; 22:212. [PMID: 39300453 PMCID: PMC11414264 DOI: 10.1186/s12915-024-01988-w] [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: 11/29/2023] [Accepted: 08/19/2024] [Indexed: 09/22/2024] Open
Abstract
BACKGROUND Wnt signaling pathways play crucial roles in animal development. They establish embryonic axes, specify cell fates, and regulate tissue morphogenesis from the early embryo to organogenesis. It is becoming increasingly recognized that these distinct developmental outcomes depend upon dynamic interactions between multiple ligands, receptors, antagonists, and other pathway modulators, consolidating the view that a combinatorial "code" controls the output of Wnt signaling. However, due to the lack of comprehensive analyses of Wnt components in several animal groups, it remains unclear if specific combinations always give rise to specific outcomes, and if these combinatorial patterns are conserved throughout evolution. RESULTS In this work, we investigate the combinatorial expression of Wnt signaling components during the axial patterning of the brachiopod Terebratalia transversa. We find that T. transversa has a conserved repertoire of ligands, receptors, and antagonists. These genes are expressed throughout embryogenesis but undergo significant upregulation during axial elongation. At this stage, Frizzled domains occupy broad regions across the body while Wnt domains are narrower and distributed in partially overlapping patches; antagonists are mostly restricted to the anterior end. Based on their combinatorial expression, we identify a series of unique transcriptional subregions along the anteroposterior axis that coincide with the different morphological subdivisions of the brachiopod larval body. When comparing these data across the animal phylogeny, we find that the expression of Frizzled genes is relatively conserved, whereas the expression of Wnt genes is more variable. CONCLUSIONS Our results suggest that the differential activation of Wnt signaling pathways may play a role in regionalizing the anteroposterior axis of brachiopod larvae. More generally, our analyses suggest that changes in the receptor context of Wnt ligands may act as a mechanism for the evolution and diversification of the metazoan body axis.
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Affiliation(s)
- Bruno C Vellutini
- Michael Sars Centre, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway.
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307, Dresden, Germany.
| | - José M Martín-Durán
- Michael Sars Centre, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway
- School of Biological and Behavioural Sciences, Queen Mary University of London, Mile End Road, Fogg Building, London, E1 4NS, UK
| | - Aina Børve
- Michael Sars Centre, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway
- Department of Biological Sciences, Molecular Biology, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway
| | - Andreas Hejnol
- Michael Sars Centre, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway.
- Department of Biological Sciences, Molecular Biology, University of Bergen, Thormøhlensgate 55, 5008, Bergen, Norway.
- Institute of Zoology and Evolutionary Research, Friedrich Schiller University Jena, Erbertstraße 1, 07743, Jena, Germany.
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5
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Paczkó M, Vörös D, Szabó P, Jékely G, Szathmáry E, Szilágyi A. A neural network-based model framework for cell-fate decisions and development. Commun Biol 2024; 7:323. [PMID: 38486083 PMCID: PMC10940658 DOI: 10.1038/s42003-024-05985-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Accepted: 02/28/2024] [Indexed: 03/18/2024] Open
Abstract
Gene regulatory networks (GRNs) fulfill the essential function of maintaining the stability of cellular differentiation states by sustaining lineage-specific gene expression, while driving the progression of development. However, accounting for the relative stability of intermediate differentiation stages and their divergent trajectories remains a major challenge for models of developmental biology. Here, we develop an empirical data-based associative GRN model (AGRN) in which regulatory networks store multilineage stage-specific gene expression profiles as associative memory patterns. These networks are capable of responding to multiple instructive signals and, depending on signal timing and identity, can dynamically drive the differentiation of multipotent cells toward different cell state attractors. The AGRN dynamics can thus generate diverse lineage-committed cell populations in a robust yet flexible manner, providing an attractor-based explanation for signal-driven cell fate decisions during differentiation and offering a readily generalizable modelling tool that can be applied to a wide variety of cell specification systems.
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Affiliation(s)
- Mátyás Paczkó
- Institute of Evolution, HUN-REN Centre for Ecological Research, Konkoly-Thege M. út 29-33, 1121, Budapest, Hungary
- Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, 1117, Budapest, Hungary
| | - Dániel Vörös
- Institute of Evolution, HUN-REN Centre for Ecological Research, Konkoly-Thege M. út 29-33, 1121, Budapest, Hungary
- Doctoral School of Biology, Institute of Biology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, 1117, Budapest, Hungary
| | - Péter Szabó
- Institute of Evolution, HUN-REN Centre for Ecological Research, Konkoly-Thege M. út 29-33, 1121, Budapest, Hungary
| | - Gáspár Jékely
- Living Systems Institute, University of Exeter, Stocker Road 4QD, EX4, Exeter, UK
| | - Eörs Szathmáry
- Institute of Evolution, HUN-REN Centre for Ecological Research, Konkoly-Thege M. út 29-33, 1121, Budapest, Hungary.
- Center for the Conceptual Foundations of Science, Parmenides Foundation, Hindenburgstr. 15, 82343, Pöcking, Germany.
- Department of Plant Systematics, Ecology and Theoretical Biology, Eötvös Loránd University, Pázmány Péter sétány 1/C, 1117, Budapest, Hungary.
| | - András Szilágyi
- Institute of Evolution, HUN-REN Centre for Ecological Research, Konkoly-Thege M. út 29-33, 1121, Budapest, Hungary
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6
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Bastin BR, Meha SM, Khindurangala L, Schneider SQ. Cooption of regulatory modules for tektin paralogs during ciliary band formation in a marine annelid larva. Dev Biol 2023; 503:95-110. [PMID: 37557946 DOI: 10.1016/j.ydbio.2023.07.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Revised: 07/25/2023] [Accepted: 07/28/2023] [Indexed: 08/11/2023]
Abstract
Tektins are a highly conserved family of coiled-coil domain containing proteins known to play a role in structure, stability and function of cilia and flagella. Tektin proteins are thought to form filaments which run the length of the axoneme along the inner surface of the A tubule of each microtubule doublet. Phylogenetic analyses suggest that the tektin family arose via duplications from a single tektin gene in a unicellular organism giving rise to four and five tektin genes in bilaterians and in spiralians, respectively. Although tektins are found in most metazoans, little is known about their expression and function outside of a handful of model species. Here we present the first comprehensive study of tektin family gene expression in any animal system, in the spiralian annelid Platynereis dumerilii. This indirect developing species retains a full ancient spiralian complement of five tektin genes. We show that all five tektins are expressed almost exclusively in known ciliary structures following the expression of the motile cilia master regulator foxJ1. The three older bilaterian tektin-1, tektin-2, and tektin-4 genes, show a high degree of spatial and temporal co-regulation, while the spiralian specific tektin-3/5A and tektin-3/5B show a delay in onset of expression in every ciliary structure. In addition, tektin-3/5B transcripts show a restricted subcellular localization to the most apical region near the multiciliary arrays. The exact recapitulation of the sequence of expression and localization of the five tektins at different times during larval development indicates the cooption of a fixed regulatory and cellular program during the formation of each ciliary band and multiciliated cell type in this spiralian.
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Affiliation(s)
- Benjamin R Bastin
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA.
| | - Steffanie M Meha
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.
| | - Lalith Khindurangala
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA.
| | - Stephan Q Schneider
- Department of Genetics, Development and Cell Biology, Iowa State University, Ames, IA, USA; Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, Taiwan.
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7
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Paré L, Bideau L, Baduel L, Dalle C, Benchouaia M, Schneider SQ, Laplane L, Clément Y, Vervoort M, Gazave E. Transcriptomic landscape of posterior regeneration in the annelid Platynereis dumerilii. BMC Genomics 2023; 24:583. [PMID: 37784028 PMCID: PMC10546743 DOI: 10.1186/s12864-023-09602-z] [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: 05/25/2023] [Accepted: 08/18/2023] [Indexed: 10/04/2023] Open
Abstract
BACKGROUND Restorative regeneration, the capacity to reform a lost body part following amputation or injury, is an important and still poorly understood process in animals. Annelids, or segmented worms, show amazing regenerative capabilities, and as such are a crucial group to investigate. Elucidating the molecular mechanisms that underpin regeneration in this major group remains a key goal. Among annelids, the nereididae Platynereis dumerilii (re)emerged recently as a front-line regeneration model. Following amputation of its posterior part, Platynereis worms can regenerate both differentiated tissues of their terminal part as well as a growth zone that contains putative stem cells. While this regeneration process follows specific and reproducible stages that have been well characterized, the transcriptomic landscape of these stages remains to be uncovered. RESULTS We generated a high-quality de novo Reference transcriptome for the annelid Platynereis dumerilii. We produced and analyzed three RNA-sequencing datasets, encompassing five stages of posterior regeneration, along with blastema stages and non-amputated tissues as controls. We included two of these regeneration RNA-seq datasets, as well as embryonic and tissue-specific datasets from the literature to produce a Reference transcriptome. We used this Reference transcriptome to perform in depth analyzes of RNA-seq data during the course of regeneration to reveal the important dynamics of the gene expression, process with thousands of genes differentially expressed between stages, as well as unique and specific gene expression at each regeneration stage. The study of these genes highlighted the importance of the nervous system at both early and late stages of regeneration, as well as the enrichment of RNA-binding proteins (RBPs) during almost the entire regeneration process. CONCLUSIONS In this study, we provided a high-quality de novo Reference transcriptome for the annelid Platynereis that is useful for investigating various developmental processes, including regeneration. Our extensive stage-specific transcriptional analysis during the course of posterior regeneration sheds light upon major molecular mechanisms and pathways, and will foster many specific studies in the future.
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Affiliation(s)
- Louis Paré
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Loïc Bideau
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Loeiza Baduel
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Caroline Dalle
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Médine Benchouaia
- Département de biologie, GenomiqueENS, Institut de Biologie de l'ENS (IBENS), École normale supérieure, CNRS, INSERM, Université PSL, Paris, 75005, France
| | - Stephan Q Schneider
- Institute of Cellular and Organismic Biology, Academia Sinica, Taipei, 11529, Taiwan
| | - Lucie Laplane
- Université Paris I Panthéon-Sorbonne, CNRS UMR 8590 Institut d'Histoire et de Philosophie des Sciences et des Techniques (IHPST), Paris, France
- Gustave Roussy, UMR 1287, Villejuif, France
| | - Yves Clément
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Michel Vervoort
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France
| | - Eve Gazave
- Université Paris Cité, CNRS, Institut Jacques Monod, Paris, F-75013, France.
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8
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Morino Y, Yoshikawa H. Role of maternal spiralian-specific homeobox gene SPILE-E in the specification of blastomeres along the animal-vegetal axis during the early cleavage stages of mollusks. Dev Growth Differ 2023; 65:384-394. [PMID: 37392142 DOI: 10.1111/dgd.12874] [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: 03/30/2023] [Revised: 05/24/2023] [Accepted: 06/26/2023] [Indexed: 07/03/2023]
Abstract
Spiralians, one of the major clades of bilaterians, share a unique development known as spiralian development, characterized by the formation of tiers of cells called quartets, which exhibit different developmental potentials along the animal-vegetal axis. Recently, spiralian-specific TALE-type homeobox genes (SPILE) have been identified, some of which show zygotic and staggered expression patterns along the animal-vegetal axis and function in quartet specification in mollusks. However, it is unclear which maternal molecular components control the zygotic expression of these transcription factors. In this study, we focused on SPILE-E, a maternal transcription factor, and investigated its expression and function in mollusks. We found that the maternal and ubiquitous expression of SPILE-E in the cleavage stages is conserved in molluskan species, including limpets, mussels, and chitons. We knocked down SPILE-E in limpets and revealed that the expression of transcription factors specifically expressed in the first quartet (1q2 ; foxj1b) and second quartet (2q; SPILE-B) was abolished, whereas the macromere-quartet marker (SPILE-C) was ectopically expressed in 1q2 in SPILE-E morphants. Moreover, we showed that the expression of SPILE-A, which upregulates SPILE-B but represses SPILE-C expression, decreased in SPILE-E morphants. Consistent with changes in the expression pattern of the above transcription factors, SPILE-E-morphant larvae exhibited patchy or complete loss of expression of marker genes of ciliated cells and shell fields, possibly reflecting incomplete specification of 1q2 and 2q. Our results provide a molecular framework for quartet specification and highlight the importance of maternal lineage-specific transcription factors in the development and evolution of spiralians.
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Affiliation(s)
- Yoshiaki Morino
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Japan
| | - Hiroki Yoshikawa
- Graduate School of Science and Life Technology, University of Tsukuba, Tsukuba, Japan
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9
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Habib SJ, Acebrón SP. Wnt signalling in cell division: from mechanisms to tissue engineering. Trends Cell Biol 2022; 32:1035-1048. [PMID: 35717422 DOI: 10.1016/j.tcb.2022.05.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Revised: 05/23/2022] [Accepted: 05/24/2022] [Indexed: 01/21/2023]
Abstract
Wnt signalling is an essential player in tissue formation, notably in the regulation of stem cell function. Wnt signalling is best known for its roles in G1/S progression. However, a complex Wnt programme that also mediates mitotic progression and asymmetric cell division (ACD) is emerging. Recent developments in this area have provided mechanistic insights as well as tools to engineer or target Wnt signalling for translational and therapeutic purposes. Here, we discuss the bidirectional relationship between Wnt activity and mitosis. We emphasise how various Wnt-dependent mechanisms control spindle dynamics, chromosome segregation, and ACD. Finally, we illustrate how knowledge about these mechanisms has been successfully employed in tissue engineering for regenerative medicine applications.
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Affiliation(s)
- Shukry J Habib
- Department of Biomedical Sciences, University of Lausanne, Rue du Bugnon 7a, CH-1005 Lausanne, Switzerland.
| | - Sergio P Acebrón
- Centre for Organismal Studies (COS), University of Heidelberg, Im Neuenheimer Feld 230, 69120 Heidelberg, Germany.
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10
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Ribeiro RP, Aguado MT. Effects of GSK3β inhibition in the regeneration of Syllis malaquini (Syllidae, Annelida). Dev Genes Evol 2021; 231:141-146. [PMID: 34635948 DOI: 10.1007/s00427-021-00681-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 09/23/2021] [Indexed: 02/02/2023]
Abstract
The Wnt/β-catenin signaling pathway has been widely associated to the reestablishment of anteroposterior body polarities in the embryonic development and regeneration in animals. For instance, in annelids, cellular proliferation, wound healing, and blastema development can be affected when this pathway is disrupted. However, very little is known about the genetic regulatory processes involved in these anomalies. Here, we investigate the morphological effects of 1-azakenpaullone, a pharmacological inhibitor of GSK3β that is supposed to over-activate the Wnt/β-catenin pathway, during the anterior and posterior regeneration of the annelid Syllis malaquini. The results showed that high concentrations of 1-azakenpaullone affect the stages of blastema differentiation and resegmentation. Therefore, GSK3β-associated gene regulatory networks are candidate to investigate the genetic mechanisms involved in the regular course of S. malaquini regeneration.
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Affiliation(s)
| | - M Teresa Aguado
- Biodiversitätsmuseum, Animal Evolution & Biodiversity, Georg-August-Universität Göttingen, Göttingen, Germany.
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11
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Özpolat BD, Randel N, Williams EA, Bezares-Calderón LA, Andreatta G, Balavoine G, Bertucci PY, Ferrier DEK, Gambi MC, Gazave E, Handberg-Thorsager M, Hardege J, Hird C, Hsieh YW, Hui J, Mutemi KN, Schneider SQ, Simakov O, Vergara HM, Vervoort M, Jékely G, Tessmar-Raible K, Raible F, Arendt D. The Nereid on the rise: Platynereis as a model system. EvoDevo 2021; 12:10. [PMID: 34579780 PMCID: PMC8477482 DOI: 10.1186/s13227-021-00180-3] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 08/20/2021] [Indexed: 01/02/2023] Open
Abstract
The Nereid Platynereis dumerilii (Audouin and Milne Edwards (Annales des Sciences Naturelles 1:195-269, 1833) is a marine annelid that belongs to the Nereididae, a family of errant polychaete worms. The Nereid shows a pelago-benthic life cycle: as a general characteristic for the superphylum of Lophotrochozoa/Spiralia, it has spirally cleaving embryos developing into swimming trochophore larvae. The larvae then metamorphose into benthic worms living in self-spun tubes on macroalgae. Platynereis is used as a model for genetics, regeneration, reproduction biology, development, evolution, chronobiology, neurobiology, ecology, ecotoxicology, and most recently also for connectomics and single-cell genomics. Research on the Nereid started with studies on eye development and spiralian embryogenesis in the nineteenth and early twentieth centuries. Transitioning into the molecular era, Platynereis research focused on posterior growth and regeneration, neuroendocrinology, circadian and lunar cycles, fertilization, and oocyte maturation. Other work covered segmentation, photoreceptors and other sensory cells, nephridia, and population dynamics. Most recently, the unique advantages of the Nereid young worm for whole-body volume electron microscopy and single-cell sequencing became apparent, enabling the tracing of all neurons in its rope-ladder-like central nervous system, and the construction of multimodal cellular atlases. Here, we provide an overview of current topics and methodologies for P. dumerilii, with the aim of stimulating further interest into our unique model and expanding the active and vibrant Platynereis community.
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Affiliation(s)
- B. Duygu Özpolat
- Eugene Bell Center for Regenerative Biology and Tissue Engineering, Marine Biological Laboratory, Woods Hole, MA 02543 USA
| | - Nadine Randel
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, CB2 3EJ UK
| | - Elizabeth A. Williams
- Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, UK
| | | | - Gabriele Andreatta
- Max Perutz Labs, University of Vienna, Dr. Bohr-Gasse 9/4, 1030 Vienna, Austria
| | - Guillaume Balavoine
- Institut Jacques Monod, University of Paris/CNRS, 15 rue Hélène Brion, 75013 Paris, France
| | - Paola Y. Bertucci
- European Molecular Biology Laboratory, Developmental Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - David E. K. Ferrier
- Gatty Marine Laboratory, The Scottish Oceans Institute, University of St Andrews, East Sands, St Andrews, Fife, KY16 8LB UK
| | | | - Eve Gazave
- Institut Jacques Monod, University of Paris/CNRS, 15 rue Hélène Brion, 75013 Paris, France
| | - Mette Handberg-Thorsager
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Jörg Hardege
- Department of Biological & Marine Sciences, Hull University, Cottingham Road, Hull, HU67RX UK
| | - Cameron Hird
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, UK
| | - Yu-Wen Hsieh
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, 01307 Dresden, Germany
| | - Jerome Hui
- School of Life Sciences, Simon F.S. Li Marine Science Laboratory, State Key Laboratory of Agrobiotechnology, The Chinese University of Hong Kong, Hong Kong, China
| | - Kevin Nzumbi Mutemi
- European Molecular Biology Laboratory, Developmental Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
| | - Stephan Q. Schneider
- Institute of Cellular and Organismic Biology, Academia Sinica, No. 128, Sec. 2, Academia Road, Nankang, Taipei, 11529 Taiwan
| | - Oleg Simakov
- Department for Neurosciences and Developmental Biology, University of Vienna, Vienna, Austria
| | - Hernando M. Vergara
- Sainsbury Wellcome Centre for Neural Circuits and Behaviour, Howland Street 25, London, W1T 4JG UK
| | - Michel Vervoort
- Institut Jacques Monod, University of Paris/CNRS, 15 rue Hélène Brion, 75013 Paris, France
| | - Gáspár Jékely
- Living Systems Institute, University of Exeter, Stocker Road, Exeter, UK
| | | | - Florian Raible
- Max Perutz Labs, University of Vienna, Dr. Bohr-Gasse 9/4, 1030 Vienna, Austria
| | - Detlev Arendt
- European Molecular Biology Laboratory, Developmental Biology Unit, Meyerhofstrasse 1, 69117 Heidelberg, Germany
- Centre for Organismal Studies (COS), University of Heidelberg, 69120 Heidelberg, Germany
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12
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Vora SM, Fassler JS, Phillips BT. Centrosomes are required for proper β-catenin processing and Wnt response. Mol Biol Cell 2020; 31:1951-1961. [PMID: 32583737 PMCID: PMC7525817 DOI: 10.1091/mbc.e20-02-0139] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The Wnt/β-catenin signaling pathway is central to metazoan development and routinely dysregulated in cancer. Wnt/β-catenin signaling initiates transcriptional reprogramming upon stabilization of the transcription factor β-catenin, which is otherwise posttranslationally processed by a destruction complex and degraded by the proteasome. Since various Wnt signaling components are enriched at centrosomes, we examined the functional contribution of centrosomes to Wnt signaling, β-catenin regulation, and posttranslational modifications. In HEK293 cells depleted of centrosomes we find that β-catenin synthesis and degradation rates are unaffected but that the normal accumulation of β-catenin in response to Wnt signaling is attenuated. This is due to accumulation of a novel high-molecular-weight form of phosphorylated β-catenin that is constitutively degraded in the absence of Wnt. Wnt signaling operates by inhibiting the destruction complex and thereby reducing destruction complex–phosphorylated β-catenin, but high-molecular-weight β-catenin is unexpectedly increased by Wnt signaling. Therefore these studies have identified a pool of β-catenin effectively shielded from regulation by Wnt. We present a model whereby centrosomes prevent inappropriate β-catenin modifications that antagonize normal stabilization by Wnt signals.
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Affiliation(s)
- Setu M Vora
- Department of Biology, University of Iowa, Iowa City, IA 52242-1324
| | - Jan S Fassler
- Department of Biology, University of Iowa, Iowa City, IA 52242-1324
| | - Bryan T Phillips
- Department of Biology, University of Iowa, Iowa City, IA 52242-1324
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13
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Kostyuchenko RP, Kozin VV. Morphallaxis versus Epimorphosis? Cellular and Molecular Aspects of Regeneration and Asexual Reproduction in Annelids. BIOL BULL+ 2020. [DOI: 10.1134/s1062359020030048] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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14
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Kozmikova I, Kozmik Z. Wnt/β-catenin signaling is an evolutionarily conserved determinant of chordate dorsal organizer. eLife 2020; 9:56817. [PMID: 32452768 PMCID: PMC7292647 DOI: 10.7554/elife.56817] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Accepted: 05/25/2020] [Indexed: 12/11/2022] Open
Abstract
Deciphering the mechanisms of axis formation in amphioxus is a key step to understanding the evolution of chordate body plan. The current view is that Nodal signaling is the only factor promoting the dorsal axis specification in the amphioxus, whereas Wnt/β-catenin signaling plays no role in this process. Here, we re-examined the role of Wnt/βcatenin signaling in the dorsal/ventral patterning of amphioxus embryo. We demonstrated that the spatial activity of Wnt/β-catenin signaling is located in presumptive dorsal cells from cleavage to gastrula stage, and provided functional evidence that Wnt/β-catenin signaling is necessary for the specification of dorsal cell fate in a stage-dependent manner. Microinjection of Wnt8 and Wnt11 mRNA induced ectopic dorsal axis in neurulae and larvae. Finally, we demonstrated that Nodal and Wnt/β-catenin signaling cooperate to promote the dorsal-specific gene expression in amphioxus gastrula. Our study reveals high evolutionary conservation of dorsal organizer formation in the chordate lineage.
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Affiliation(s)
- Iryna Kozmikova
- Laboratory of Transcriptional Regulation, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
| | - Zbynek Kozmik
- Laboratory of Transcriptional Regulation, Institute of Molecular Genetics of the Czech Academy of Sciences, Prague, Czech Republic
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15
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Wada H, Phuangphong S, Hashimoto N, Nagai K. Establishment of the novel bivalve body plan through modification of early developmental events in mollusks. Evol Dev 2020; 22:463-470. [PMID: 32291900 DOI: 10.1111/ede.12334] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Mollusks have a wide variety of body plans, which develop through conserved early embryogenesis, namely spiral embryonic development and trochophore larvae. Although the comparative study of mollusks has attracted the interest of evolutionary developmental biology researchers, less attention has been paid to bivalves. In this review, we focused on the evolutionary process from single-shell ancestors to bivalves, which possess bilaterally separated shells. Our study tracing the lineage of shell field cells in bivalves did not support the old hypothesis that shell plate morphology is due to modification of the spiral cleavage pattern. Rather, we suggest that modification of the shell field induction process is the key to understanding the evolution of shell morphology. The novel body plan of bivalves cannot be established solely via separating shell plates, but rather requires the formation of additional organs, such as adductor muscles. The evolutionary biology of bivalves offers a unique view on how multiple organs evolve in a coordinated manner to establish a novel body plan.
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Affiliation(s)
- Hiroshi Wada
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Supanat Phuangphong
- School of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki, Japan
| | - Naoki Hashimoto
- Pearl Research Institute, K. Mikimoto & Co., Ltd., Shima, Mie, Japan
| | - Kiyohito Nagai
- Pearl Research Institute, K. Mikimoto & Co., Ltd., Shima, Mie, Japan
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16
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Abstract
Snails, earthworms and flatworms are remarkably different animals, but they all exhibit a very similar mode of early embryogenesis: spiral cleavage. This is one of the most widespread developmental programs in animals, probably ancestral to almost half of the animal phyla, and therefore its study is essential for understanding animal development and evolution. However, our knowledge of spiral cleavage is still in its infancy. Recent technical and conceptual advances, such as the establishment of genome editing and improved phylogenetic resolution, are paving the way for a fresher and deeper look into this fascinating early cleavage mode.
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Affiliation(s)
- José M Martín-Durán
- Queen Mary, University of London, School of Biological and Chemical Sciences, Mile End Road, E1 4NS London, UK
| | - Ferdinand Marlétaz
- Molecular Genetics Unit, Okinawa Institute of Science & Technology, 1919-1, Tancha, Onna 904-0495, Japan
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17
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Vopalensky P, Tosches MA, Achim K, Handberg-Thorsager M, Arendt D. From spiral cleavage to bilateral symmetry: the developmental cell lineage of the annelid brain. BMC Biol 2019; 17:81. [PMID: 31640768 PMCID: PMC6805352 DOI: 10.1186/s12915-019-0705-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Accepted: 10/01/2019] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND During early development, patterns of cell division-embryonic cleavage-accompany the gradual restriction of blastomeres to specific cell fates. In Spiralia, which include annelids, mollusks, and flatworms, "spiral cleavage" produces a highly stereotypic, spiral-like arrangement of blastomeres and swimming trochophore-type larvae with rotational (spiral) symmetry. However, starting at larval stages, spiralian larvae acquire elements of bilateral symmetry, before they metamorphose into fully bilateral juveniles. How this spiral-to-bilateral transition occurs is not known and is especially puzzling for the early differentiating brain and head sensory organs, which emerge directly from the spiral cleavage pattern. Here we present the developmental cell lineage of the Platynereis larval episphere. RESULTS Live-imaging recordings from the zygote to the mid-trochophore stage (~ 30 hpf) of the larval episphere of the marine annelid Platynereis dumerilii reveal highly stereotypical development and an invariant cell lineage of early differentiating cell types. The larval brain and head sensory organs develop from 11 pairs of bilateral founders, each giving rise to identical clones on the right and left body sides. Relating the origin of each bilateral founder pair back to the spiral cleavage pattern, we uncover highly divergent origins: while some founder pairs originate from corresponding cells in the spiralian lineage on each body side, others originate from non-corresponding cells, and yet others derive from a single cell within one quadrant. Integrating lineage and gene expression data for several embryonic and larval stages, we find that the conserved head patterning genes otx and six3 are expressed in bilateral founders representing divergent lineage histories and giving rise to early differentiating cholinergic neurons and head sensory organs, respectively. CONCLUSIONS We present the complete developmental cell lineage of the Platynereis larval episphere, and thus the first comprehensive account of the spiral-to-bilateral transition in a developing spiralian. The bilateral symmetry of the head emerges from pairs of bilateral founders, similar to the trunk; however, the head founders are more numerous and show striking left-right asymmetries in lineage behavior that we relate to differential gene expression.
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Affiliation(s)
- Pavel Vopalensky
- Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany
| | - Maria Antonietta Tosches
- Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany
| | - Kaia Achim
- Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany
| | - Mette Handberg-Thorsager
- Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany
- Max Planck Institute of Molecular Cell Biology and Genetics, Pfotenhauerstraße 108, Dresden, 01307, Germany
| | - Detlev Arendt
- Developmental Biology Unit, European Molecular Biology Laboratory, Meyerhofstraße 1, 69117, Heidelberg, Germany.
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18
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Kozin VV, Borisenko IE, Kostyuchenko RP. Establishment of the Axial Polarity and Cell Fate in Metazoa via Canonical Wnt Signaling: New Insights from Sponges and Annelids. BIOL BULL+ 2019. [DOI: 10.1134/s1062359019010035] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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19
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Takahashi H, Abe M, Kuroda R. GSK3β controls the timing and pattern of the fifth spiral cleavage at the 2-4 cell stage in Lymnaea stagnalis. Dev Genes Evol 2019; 229:73-81. [PMID: 30631925 DOI: 10.1007/s00427-018-00625-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 12/27/2018] [Indexed: 11/26/2022]
Abstract
Establishment of the body plan of multicellular organisms by the primary body axis determination and cell-fate specification is a key issue in biology. We have examined the mRNA localization of three Wnt pathway components gsk3β, β-catenin, and disheveled and investigated the effects of four selective inhibitors of these proteins on the early developmental stages of the spiral cleavage embryo of the fresh water snail Lymnaea (L.) stagnalis. mRNAs for gsk3β and β-catenin were distributed uniformly throughout the embryo during development whereas disheveled mRNA showed specific localization with intra- and inter-blastomere differences in concentration along the A-V axis during spiral cleavages. Remarkably, through inhibitor studies, we identified a short sensitive period from the 2- to 4-cell stage in which GSK3β inhibition by the highly specific 1-azakenpaullone (AZ) and by LiCl induced a subsequent dramatic developmental delay and alteration of the cleavage patterns of blastomeres at the fifth cleavage (16- to 24-cell stage) resulting in exogastrulation and other abnormalities in later stages. Inhibition of β-Catenin or Disheveled had no effect. Our inhibitor experiments establish a novel role for GSK3β in the developmental timing and orientated cell division of the snail embryo. Further work will be needed to identify the downstream targets of the kinase.
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Affiliation(s)
- Hiromi Takahashi
- Department of Applied Biological Science, Graduate School of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, 278-8510, Japan
| | - Masanori Abe
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, 278-8510, Japan
| | - Reiko Kuroda
- Department of Applied Biological Science, Graduate School of Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, 278-8510, Japan.
- Research Institute for Science and Technology, Tokyo University of Science, 2641 Yamazaki, Noda-shi, Chiba, 278-8510, Japan.
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20
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Onai T. Canonical Wnt/β-catenin and Notch signaling regulate animal/vegetal axial patterning in the cephalochordate amphioxus. Evol Dev 2018; 21:31-43. [PMID: 30288919 DOI: 10.1111/ede.12273] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
In bilaterians, animal/vegetal axial (A/V) patterning is a fundamental early developmental event for establishment of animal/vegetal polarity and following specification of the germ layers (ectoderm, mesoderm, endoderm), of which the evolutionary origin is enigmatic. Understanding A/V axial patterning in a basal animal from each phylum would help to reconstruct the ancestral state of germ layer specification in bilaterians and thus, the evolution of mesoderm, the third intermediate cell layer. Herein, data show that the canonical Wnt/β-catenin (cWnt) and Notch signaling pathways control mesoderm specification from the early endomesoderm in the basal chordate amphioxus. Amphioxus belongs to the deuterostome, one of the main superphyla in Bilateria. In the present study, genes (tcf, dsh, axin, gsk3β) encoding cWnt components were expressed in the endomesoderm during the gastrula stages. Excess cWnt signaling by BIO, a GSK3 inhibitor, expanded the expression domains of outer endomesodermal genes that include future mesodermal ones and suppressed inner endomesodermal and ectodermal genes. Interfering Notch signaling by DAPT, a γ-secretase inhibitor, resulted in decreased expression of ectodermal and endomesodermal markers. These results suggest that cWnt and Notch have important roles in mesoderm specification in amphioxus embryos. The evolution of the mesoderm is also discussed.
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Affiliation(s)
- Takayuki Onai
- Department of Anatomy, University of Fukui, School of Medical Sciences, Fukui, Japan.,Life Science Innovation Center, University of Fukui, Fukui, Japan
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21
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Chou HC, Acevedo-Luna N, Kuhlman JA, Schneider SQ. PdumBase: a transcriptome database and research tool for Platynereis dumerilii and early development of other metazoans. BMC Genomics 2018; 19:618. [PMID: 30115014 PMCID: PMC6097317 DOI: 10.1186/s12864-018-4987-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Accepted: 07/31/2018] [Indexed: 12/22/2022] Open
Abstract
BACKGROUND The marine polychaete annelid Platynereis dumerilii has recently emerged as a prominent organism for the study of development, evolution, stem cells, regeneration, marine ecology, chronobiology and neurobiology within metazoans. Its phylogenetic position within the spiralian/ lophotrochozoan clade, the comparatively high conservation of ancestral features in the Platynereis genome, and experimental access to any stage within its life cycle, make Platynereis an important model for elucidating the complex regulatory and functional molecular mechanisms governing early development, later organogenesis, and various features of its larval and adult life. High resolution RNA-seq gene expression data obtained from specific developmental stages can be used to dissect early developmental mechanisms. However, the potential for discovery of these mechanisms relies on tools to search, retrieve, and compare genome-wide information within Platynereis, and across other metazoan taxa. RESULTS To facilitate exploration and discovery by the broader scientific community, we have developed a web-based, searchable online research tool, PdumBase, featuring the first comprehensive transcriptome database for Platynereis dumerilii during early stages of development (2 h ~ 14 h). Our database also includes additional stages over the P. dumerilii life cycle and provides access to the expression data of 17,213 genes (31,806 transcripts) along with annotation information sourced from Swiss-Prot, Gene Ontology, KEGG pathways, Pfam domains, TmHMM, SingleP, and EggNOG orthology. Expression data for each gene includes the stage, the normalized FPKM, the raw read counts, and information that can be leveraged for statistical analyses of differential gene expression and the construction of genome-wide co-expression networks. In addition, PdumBase offers early stage transcriptome expression data from five further species as a valuable resource for investigators interested in comparing early development in different organisms. To understand conservation of Platynereis gene models and to validate gene annotation, most Platynereis gene models include a comprehensive phylogenetic analysis across 18 species representing diverse metazoan taxa. CONCLUSIONS PdumBase represents the first online resource for the early developmental transcriptome of Platynereis dumerilii. It serves as a research platform for discovery and exploration of gene expression during early stages, throughout the Platynereis life cycle, and enables comparison to other model organisms. PdumBase is freely available at http://pdumbase.gdcb.iastate.edu .
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Affiliation(s)
- Hsien-Chao Chou
- Department of Genetics, Developmental and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
- Present address: Center for Cancer Research, National Institutes of Health, Rockville, MD 20894 USA
| | - Natalia Acevedo-Luna
- Department of Genetics, Developmental and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
| | - Julie A. Kuhlman
- Department of Genetics, Developmental and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
| | - Stephan Q. Schneider
- Department of Genetics, Developmental and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
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Žídek R, Machoň O, Kozmik Z. Wnt/β-catenin signalling is necessary for gut differentiation in a marine annelid, Platynereis dumerilii. EvoDevo 2018; 9:14. [PMID: 29942461 PMCID: PMC5996498 DOI: 10.1186/s13227-018-0100-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2018] [Accepted: 04/20/2018] [Indexed: 11/10/2022] Open
Abstract
Background Wnt/β-catenin (or canonical) signalling pathway activity is necessary and used independently several times for specification of vegetal fate and endoderm, gut differentiation, maintenance of epithelium in adult intestine and the development of gut-derived organs in various vertebrate and non-vertebrate organisms. However, its conservation in later stages of digestive tract development still remains questionable due to the lack of detailed data, mainly from Spiralia. Results Here we characterize the Pdu-Tcf gene, a Tcf/LEF orthologue and a component of Wnt/β-catenin pathway from Platynereis dumerilii, a spiralian, marine annelid worm. Pdu-Tcf undergoes extensive alternative splicing in the C-terminal region of the gene generating as many as eight mRNA isoforms some of which differ in the presence or absence of a C-clamp domain which suggests a distinct DNA binding activity of individual protein variants. Pdu-Tcf is broadly expressed throughout development which is indicative of many functions. One of the most prominent domains that exhibits rather strong Pdu-Tcf expression is in the putative precursors of endodermal gut cells which are detected after 72 h post-fertilization (hpf). At day 5 post-fertilization (dpf), Pdu-Tcf is expressed in the hindgut and pharynx (foregut), whereas at 7 dpf stage, it is strongly transcribed in the now-cellularized midgut for the first time. In order to gain insight into the role of Wnt/β-catenin signalling, we disrupted its activity using pharmacological inhibitors between day 5 and 7 of development. The inhibition of Wnt/β-catenin signalling led to the loss of midgut marker genes Subtilisin-1, Subtilisin-2, α-Amylase and Otx along with a drop in β-catenin protein levels, Axin expression in the gut and nearly the complete loss of proliferative activity throughout the body of larva. At the same time, a hindgut marker gene Legumain was expanded to the midgut compartment under the same conditions. Conclusions Our findings suggest that high Wnt/β-catenin signalling in the midgut might be necessary for proper differentiation of the endoderm to an epithelium capable of secreting digestive enzymes. Together, our data provide evidence for the role of Wnt/β-catenin signalling in gut differentiation in Platynereis.
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Affiliation(s)
- Radim Žídek
- 1Institute of Molecular Genetics, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Ondřej Machoň
- 1Institute of Molecular Genetics, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic.,2Present Address: Institute of Experimental Medicine, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic
| | - Zbyněk Kozmik
- 1Institute of Molecular Genetics, Czech Academy of Sciences, Vídeňská 1083, 142 20 Prague 4, Czech Republic
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Rink JC. Stem Cells, Patterning and Regeneration in Planarians: Self-Organization at the Organismal Scale. Methods Mol Biol 2018; 1774:57-172. [PMID: 29916155 DOI: 10.1007/978-1-4939-7802-1_2] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The establishment of size and shape remains a fundamental challenge in biological research that planarian flatworms uniquely epitomize. Planarians can regenerate complete and perfectly proportioned animals from tiny and arbitrarily shaped tissue pieces; they continuously renew all organismal cell types from abundant pluripotent stem cells, yet maintain shape and anatomy in the face of constant turnover; they grow when feeding and literally degrow when starving, while scaling form and function over as much as a 40-fold range in body length or an 800-fold change in total cell numbers. This review provides a broad overview of the current understanding of the planarian stem cell system, the mechanisms that pattern the planarian body plan and how the interplay between patterning signals and cell fate choices orchestrates regeneration. What emerges is a conceptual framework for the maintenance and regeneration of the planarian body plan on basis of the interplay between pluripotent stem cells and self-organizing patterns and further, the general utility of planarians as model system for the mechanistic basis of size and shape.
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Affiliation(s)
- Jochen C Rink
- Max Planck Institute of Molecular Cell Biology and Genetics, Dresden, Germany.
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24
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Nakama AB, Chou HC, Schneider SQ. The asymmetric cell division machinery in the spiral-cleaving egg and embryo of the marine annelid Platynereis dumerilii. BMC DEVELOPMENTAL BIOLOGY 2017; 17:16. [PMID: 29228898 PMCID: PMC5725810 DOI: 10.1186/s12861-017-0158-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 11/23/2017] [Indexed: 12/29/2022]
Abstract
BACKGROUND Over one third of all animal phyla utilize a mode of early embryogenesis called 'spiral cleavage' to divide the fertilized egg into embryonic cells with different cell fates. This mode is characterized by a series of invariant, stereotypic, asymmetric cell divisions (ACDs) that generates cells of different size and defined position within the early embryo. Astonishingly, very little is known about the underlying molecular machinery to orchestrate these ACDs in spiral-cleaving embryos. Here we identify, for the first time, cohorts of factors that may contribute to early embryonic ACDs in a spiralian embryo. RESULTS To do so we analyzed stage-specific transcriptome data in eggs and early embryos of the spiralian annelid Platynereis dumerilii for the expression of over 50 candidate genes that are involved in (1) establishing cortical domains such as the partitioning defective (par) genes, (2) directing spindle orientation, (3) conveying polarity cues including crumbs and scribble, and (4) maintaining cell-cell adhesion between embryonic cells. In general, each of these cohorts of genes are co-expressed exhibiting high levels of transcripts in the oocyte and fertilized single-celled embryo, with progressively lower levels at later stages. Interestingly, a small number of key factors within each ACD module show different expression profiles with increased early zygotic expression suggesting distinct regulatory functions. In addition, our analysis discovered several highly co-expressed genes that have been associated with specialized neural cell-cell recognition functions in the nervous system. The high maternal contribution of these 'neural' adhesion complexes indicates novel general adhesion functions during early embryogenesis. CONCLUSIONS Spiralian embryos are champions of ACD generating embryonic cells of different size with astonishing accuracy. Our results suggest that the molecular machinery for ACD is already stored as maternal transcripts in the oocyte. Thus, the spiralian egg can be viewed as a totipotent yet highly specialized cell that evolved to execute fast and precise ACDs during spiral cleaving stages. Our survey identifies cohorts of factors in P. dumerilii that are candidates for these molecular mechanisms and their regulation, and sets the stage for a functional dissection of ACD in a spiral-cleaving embryo.
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Affiliation(s)
- Aron B. Nakama
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
| | - Hsien-Chao Chou
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
- current address: Center for Cancer Research, National Institutes of Health, Bethesda, MD 20894 USA
| | - Stephan Q. Schneider
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
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Small molecule promotes β-catenin citrullination and inhibits Wnt signaling in cancer. Nat Chem Biol 2017; 14:94-101. [PMID: 29083417 DOI: 10.1038/nchembio.2510] [Citation(s) in RCA: 107] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 10/02/2017] [Indexed: 01/27/2023]
Abstract
Wnt (wingless)/β-catenin signaling is critical for tumor progression and is frequently activated in colorectal cancer as a result of the mutation of adenomatous polyposis coli (APC); however, therapeutic agents targeting this pathway for clinical use are lacking. Here we report that nitazoxanide (NTZ), a clinically approved antiparasitic drug, efficiently inhibits Wnt signaling independent of APC. Using chemoproteomic approaches, we have identified peptidyl arginine deiminase 2 (PAD2) as the functional target of NTZ in Wnt inhibition. By targeting PAD2, NTZ increased the deamination (citrullination) and turnover of β-catenin in colon cancer cells. Replacement of arginine residues disrupted the transcriptional activity, and NTZ induced degradation of β-catenin. In Wnt-activated colon cancer cells, knockout of either PAD2 or β-catenin substantially increased resistance to NTZ treatment. Our data highlight the potential of NTZ as a modulator of β-catenin citrullination for the treatment of cancer patients with Wnt pathway mutations.
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Expansion of TALE homeobox genes and the evolution of spiralian development. Nat Ecol Evol 2017; 1:1942-1949. [PMID: 29085062 DOI: 10.1038/s41559-017-0351-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2017] [Accepted: 09/20/2017] [Indexed: 11/08/2022]
Abstract
Spiralians, including molluscs, annelids and platyhelminths, share a unique development process that includes the typical geometry of early cleavage and early segregation of cell fate in blastomeres along the animal-vegetal axis. However, the molecular mechanisms underlying this early cell fate segregation are largely unknown. Here, we report spiralian-specific expansion of the three-amino-acid loop extension (TALE) class of homeobox genes. During early development, some of these TALE genes are expressed in staggered domains along the animal-vegetal axis in the limpet Nipponacmea fuscoviridis and the polychaete Spirobranchus kraussii. Inhibition or overexpression of these genes alters the developmental fate of blastomeres, as predicted by the gene expression patterns. These results suggest that the expansion of novel TALE genes plays a critical role in the establishment of a novel cell fate segregation mechanism in spiralians.
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Kuo DH. The polychaete-to-clitellate transition: An EvoDevo perspective. Dev Biol 2017; 427:230-240. [DOI: 10.1016/j.ydbio.2017.01.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2016] [Revised: 01/23/2017] [Accepted: 01/24/2017] [Indexed: 01/21/2023]
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Loh KM, van Amerongen R, Nusse R. Generating Cellular Diversity and Spatial Form: Wnt Signaling and the Evolution of Multicellular Animals. Dev Cell 2017; 38:643-55. [PMID: 27676437 DOI: 10.1016/j.devcel.2016.08.011] [Citation(s) in RCA: 214] [Impact Index Per Article: 26.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2016] [Revised: 07/29/2016] [Accepted: 08/22/2016] [Indexed: 01/01/2023]
Abstract
There were multiple prerequisites to the evolution of multicellular animal life, including the generation of multiple cell fates ("cellular diversity") and their patterned spatial arrangement ("spatial form"). Wnt proteins operate as primordial symmetry-breaking signals. By virtue of their short-range nature and their capacity to activate both lineage-specifying and cell-polarizing intracellular signaling cascades, Wnts can polarize cells at their site of contact, orienting the axis of cell division while simultaneously programming daughter cells to adopt diverging fates in a spatially stereotyped way. By coupling cell fate to position, symmetry-breaking Wnt signals were pivotal in constructing the metazoan body by generating cellular diversity and spatial form.
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Affiliation(s)
- Kyle M Loh
- Department of Developmental Biology, Howard Hughes Medical Institute, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305, USA
| | - Renée van Amerongen
- Section of Molecular Cytology and Van Leeuwenhoek Centre for Advanced Microscopy, Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands
| | - Roel Nusse
- Department of Developmental Biology, Howard Hughes Medical Institute, Stanford Institute for Stem Cell Biology and Regenerative Medicine, Stanford University School of Medicine, 265 Campus Drive, Stanford, CA 94305, USA.
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Kostyuchenko RP, Dondua AK. Peculiarities of isolated blastomere development of the polyhaete Alitta virens. Russ J Dev Biol 2017. [DOI: 10.1134/s1062360417030067] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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A Comparative Perspective on Wnt/β-Catenin Signalling in Cell Fate Determination. Results Probl Cell Differ 2017; 61:323-350. [PMID: 28409312 DOI: 10.1007/978-3-319-53150-2_15] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The Wnt/β-catenin pathway is an ancient and highly conserved signalling pathway that plays fundamental roles in the regulation of embryonic development and adult homeostasis. This pathway has been implicated in numerous cellular processes, including cell proliferation, differentiation, migration, morphological changes and apoptosis. In this chapter, we aim to illustrate with specific examples the involvement of Wnt/β-catenin signalling in cell fate determination. We discuss the roles of the Wnt/β-catenin pathway in specifying cell fate throughout evolution, how its function in patterning during development is often reactivated during regeneration and how perturbation of this pathway has negative consequences for the control of cell fate.The origin of all life was a single cell that had the capacity to respond to cues from the environment. With evolution, multicellular organisms emerged, and as a result, subsets of cells arose to form tissues able to respond to specific instructive signals and perform specialised functions. This complexity and specialisation required two types of messages to direct cell fate: intra- and intercellular. A fundamental question in developmental biology is to understand the underlying mechanisms of cell fate choice. Amongst the numerous external cues involved in the generation of cellular diversity, a prominent pathway is the Wnt signalling pathway in all its forms.
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31
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Sureda-Gómez M, Martín-Durán JM, Adell T. Localization of planarian β-CATENIN-1 reveals multiple roles during anterior-posterior regeneration and organogenesis. Development 2016; 143:4149-4160. [PMID: 27737903 DOI: 10.1242/dev.135152] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 10/05/2016] [Indexed: 01/09/2023]
Abstract
The β-catenin-dependent Wnt pathway exerts multiple context-dependent roles in embryonic and adult tissues. In planarians, β-catenin-1 is thought to specify posterior identities through the generation of an anteroposterior gradient. However, the existence of such a gradient has not been directly demonstrated. Here, we use a specific polyclonal antibody to demonstrate that nuclear β-CATENIN-1 exists as an anteroposterior gradient from the pre-pharyngeal region to the tail of the planarian Schmidtea polychroa High levels in the posterior region steadily decrease towards the pre-pharyngeal region but then increase again in the head region. During regeneration, β-CATENIN-1 is nuclearized in both anterior and posterior blastemas, but the canonical WNT1 ligand only influences posterior nuclearization. Additionally, β-catenin-1 is required for proper anterior morphogenesis, consistent with the high levels of nuclear β-CATENIN-1 observed in this region. We further demonstrate that β-CATENIN-1 is abundant in developing and differentiated organs, and is particularly required for the specification of the germline. Altogether, our findings provide the first direct evidence of an anteroposterior nuclear β-CATENIN-1 gradient in adult planarians and uncover novel, context-dependent roles for β-catenin-1 during anterior regeneration and organogenesis.
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Affiliation(s)
- Miquel Sureda-Gómez
- Department of Genetics and Institute of Biomedicine, University of Barcelona, Barcelona, Catalonia E-08028, Spain
| | - José M Martín-Durán
- Sars International Centre for Marine Molecular Biology, University of Bergen, Thørmohlensgate 55, Bergen 5008, Norway
| | - Teresa Adell
- Department of Genetics and Institute of Biomedicine, University of Barcelona, Barcelona, Catalonia E-08028, Spain
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Chou HC, Pruitt MM, Bastin BR, Schneider SQ. A transcriptional blueprint for a spiral-cleaving embryo. BMC Genomics 2016; 17:552. [PMID: 27496340 PMCID: PMC4974748 DOI: 10.1186/s12864-016-2860-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 06/29/2016] [Indexed: 01/29/2023] Open
Abstract
Background The spiral cleavage mode of early development is utilized in over one-third of all animal phyla and generates embryonic cells of different size, position, and fate through a conserved set of stereotypic and invariant asymmetric cell divisions. Despite the widespread use of spiral cleavage, regulatory and molecular features for any spiral-cleaving embryo are largely uncharted. To address this gap we use RNA-sequencing on the spiralian model Platynereis dumerilii to capture and quantify the first complete genome-wide transcriptional landscape of early spiral cleavage. Results RNA-sequencing datasets from seven stages in early Platynereis development, from the zygote to the protrochophore, are described here including the de novo assembly and annotation of ~17,200 Platynereis genes. Depth and quality of the RNA-sequencing datasets allow the identification of the temporal onset and level of transcription for each annotated gene, even if the expression is restricted to a single cell. Over 4000 transcripts are maternally contributed and cleared by the end of the early spiral cleavage phase. Small early waves of zygotic expression are followed by major waves of thousands of genes, demarcating the maternal to zygotic transition shortly after the completion of spiral cleavages in this annelid species. Conclusions Our comprehensive stage-specific transcriptional analysis of early embryonic stages in Platynereis elucidates the regulatory genome during early spiral embryogenesis and defines the maternal to zygotic transition in Platynereis embryos. This transcriptome assembly provides the first systems-level view of the transcriptional and regulatory landscape for a spiral-cleaving embryo. Electronic supplementary material The online version of this article (doi:10.1186/s12864-016-2860-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Hsien-Chao Chou
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA, 50011, USA.,Present Address: National Cancer Institute, US National Institutes of Health, Bethesda, Maryland, USA
| | - Margaret M Pruitt
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA, 50011, USA.,Present Address: Department of Pediatrics, University of Chicago, Chicago, IL, USA
| | - Benjamin R Bastin
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA, 50011, USA
| | - Stephan Q Schneider
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA, 50011, USA.
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33
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Perry KJ, Lyons DC, Truchado-Garcia M, Fischer AHL, Helfrich LW, Johansson KB, Diamond JC, Grande C, Henry JQ. Deployment of regulatory genes during gastrulation and germ layer specification in a model spiralian mollusc Crepidula. Dev Dyn 2016. [PMID: 26197970 DOI: 10.1002/dvdy.24308] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND During gastrulation, endoderm and mesoderm are specified from a bipotential precursor (endomesoderm) that is argued to be homologous across bilaterians. Spiralians also generate mesoderm from ectodermal precursors (ectomesoderm), which arises near the blastopore. While a conserved gene regulatory network controls specification of endomesoderm in deuterostomes and ecdysozoans, little is known about genes controlling specification or behavior of either source of spiralian mesoderm or the digestive tract. RESULTS Using the mollusc Crepidula, we examined conserved regulatory factors and compared their expression to fate maps to score expression in the germ layers, blastopore lip, and digestive tract. Many genes were expressed in both ecto- and endomesoderm, but only five were expressed in ectomesoderm exclusively. The latter may contribute to epithelial-to-mesenchymal transition seen in ectomesoderm. CONCLUSIONS We present the first comparison of genes expressed during spiralian gastrulation in the context of high-resolution fate maps. We found variation of genes expressed in the blastopore lip, mouth, and cells that will form the anus. Shared expression of many genes in both mesodermal sources suggests that components of the conserved endomesoderm program were either co-opted for ectomesoderm formation or that ecto- and endomesoderm are derived from a common mesodermal precursor that became subdivided into distinct domains during evolution.
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Affiliation(s)
- Kimberly J Perry
- University of Illinois, Department of Cell and Developmental Biology, Urbana, Illinois
| | | | - Marta Truchado-Garcia
- Departamento de Biología Molecular and Centro de Biología Molecular, "Severo Ochoa" (CSIC, Universidad Autónoma de Madrid), Madrid, Spain
| | - Antje H L Fischer
- Department of Metabolic Biochemistry, Ludwig-Maximilians-University, Munich, Germany.,Marine Biological Laboratory, Woods Hole, Massachusetts
| | | | - Kimberly B Johansson
- Marine Biological Laboratory, Woods Hole, Massachusetts.,Department of Molecular and Cellular Biology, Harvard University, Cambridge, Massachusetts
| | | | - Cristina Grande
- Departamento de Biología Molecular and Centro de Biología Molecular, "Severo Ochoa" (CSIC, Universidad Autónoma de Madrid), Madrid, Spain
| | - Jonathan Q Henry
- University of Illinois, Department of Cell and Developmental Biology, Urbana, Illinois
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Kozin VV, Filimonova DA, Kupriashova EE, Kostyuchenko RP. Mesoderm patterning and morphogenesis in the polychaete Alitta virens (Spiralia, Annelida): Expression of mesodermal markers Twist, Mox, Evx and functional role for MAP kinase signaling. Mech Dev 2016; 140:1-11. [PMID: 27000638 DOI: 10.1016/j.mod.2016.03.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 03/14/2016] [Accepted: 03/15/2016] [Indexed: 12/11/2022]
Abstract
Mesoderm represents the evolutionary youngest germ layer and forms numerous novel tissues in bilaterian animals. Despite the established conservation of the gene regulatory networks that drive mesoderm differentiation (e.g. myogenesis), mechanisms of mesoderm specification are highly variable in distant model species. Thus, broader phylogenetic sampling is required to reveal common features of mesoderm formation across bilaterians. Here we focus on a representative of Spiralia, the marine annelid Alitta virens, whose mesoderm development is still poorly investigated on the molecular level. We characterize three novel early mesodermal markers for A. virens - Twist, Mox, and Evx - which are differentially expressed within the mesodermal lineages. The Twist mRNA is ubiquitously distributed in the fertilized egg and exhibits specific expression in endomesodermal- and ectomesodermal-founder cells at gastrulation. Twist is expressed around the blastopore and later in a segmental metameric pattern. We consider this expression to be ancestral, and in support of the enterocoelic hypothesis of mesoderm evolution. We also revealed an early pattern of the MAPK activation in A. virens that is different from the previously reported pattern in spiralians. Inhibition of the MAPK pathway by U0126 disrupts the metameric Twist and Mox expression, indicating an early requirement of the MAPK cascade for proper morphogenesis of endomesodermal tissues.
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Affiliation(s)
- Vitaly V Kozin
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7-9, 199034 St. Petersburg, Russia.
| | - Daria A Filimonova
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7-9, 199034 St. Petersburg, Russia
| | - Ekaterina E Kupriashova
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7-9, 199034 St. Petersburg, Russia
| | - Roman P Kostyuchenko
- Department of Embryology, St. Petersburg State University, Universitetskaya nab. 7-9, 199034 St. Petersburg, Russia.
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Bertrand V. β-catenin-driven binary cell fate decisions in animal development. WILEY INTERDISCIPLINARY REVIEWS-DEVELOPMENTAL BIOLOGY 2016; 5:377-88. [PMID: 26952169 PMCID: PMC5069452 DOI: 10.1002/wdev.228] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 12/06/2015] [Accepted: 12/29/2015] [Indexed: 02/05/2023]
Abstract
The Wnt/β‐catenin pathway plays key roles during animal development. In several species, β‐catenin is used in a reiterative manner to regulate cell fate diversification between daughter cells following division. This binary cell fate specification mechanism has been observed in animals that belong to very diverse phyla: the nematode Caenorhabditis elegans, the annelid Platynereis, and the ascidian Ciona. It may also play a role in the regulation of several stem cell lineages in vertebrates. While the molecular mechanism behind this binary cell fate switch is not fully understood, it appears that both secreted Wnt ligands and asymmetric cortical factors contribute to the generation of the difference in nuclear β‐catenin levels between daughter cells. β‐Catenin then cooperates with lineage specific transcription factors to induce the expression of novel sets of transcription factors at each round of divisions, thereby diversifying cell fate. WIREs Dev Biol 2016, 5:377–388. doi: 10.1002/wdev.228 For further resources related to this article, please visit the WIREs website.
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Affiliation(s)
- Vincent Bertrand
- Aix-Marseille Université, CNRS, Institut de Biologie du Développement de Marseille, Marseille, France
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36
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Mohri M, Hashimoto N, Wada H. Lineage tracing of the bivalve shell field with special interest in the descendants of the 2d blastomere. Biol Lett 2016; 12:20151055. [PMID: 26932681 DOI: 10.1098/rsbl.2015.1055] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
By evolving bilaterally separated shell plates, bivalves acquired a unique body plan in which their soft tissues are completely protected by hard shell plates. In this unique body plan, mobility between the separated shell plates is provided by novel structures such as a ligament and adductor muscles. As a first step towards understanding how the bivalve body plan was established, we investigated the development of the separated shell plates and ligament. Over 100 years ago, it was hypothesized that the development of separated shell plates is tightly linked with the unique cell cleavage (division) pattern of bivalves during development, wherein each bilateral daughter cell of the 2d descendant 2d(1121) develops into one of the bilateral shell fields. In this study, we tested this hypothesis by tracing the cell lineages of the Japanese purple mussel Septifer virgatus. Although the shell fields were found to be exclusively derived from the bilateral descendant cells of 2d: 2d(11211) and 2d(11212), the descendants of these cells were not restricted to shell fields alone, nor were they confined to the left or right side of the shell field based on their lineage. Our study demonstrated that ligament cells are also derived from 2d(11211) and 2d(11212), indicating that the ligament cells emerged as a subpopulation of shell field cells. This also suggests that the establishment of the novel developmental system for the ligament cells was critical for the evolution of the unique body plan of bivalves.
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Affiliation(s)
- Masakuni Mohri
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | - Naoki Hashimoto
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
| | - Hiroshi Wada
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-8572, Japan
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Bastin BR, Chou HC, Pruitt MM, Schneider SQ. Structure, phylogeny, and expression of the frizzled-related gene family in the lophotrochozoan annelid Platynereis dumerilii. EvoDevo 2015; 6:37. [PMID: 26640641 PMCID: PMC4669655 DOI: 10.1186/s13227-015-0032-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 11/13/2015] [Indexed: 12/31/2022] Open
Abstract
Background Wnt signaling pathways are highly conserved signal transduction pathways important for axis formation, cell fate specification, and organogenesis throughout metazoan development. Within the various Wnt pathways, the frizzled transmembrane receptors (Fzs) and secreted frizzled-related proteins (sFRPs) play central roles in receiving and antagonizing Wnt signals, respectively. Despite their importance, very little is known about the frizzled-related gene family (fzs & sfrps) in lophotrochozoans, especially during early stages of spiralian development. Here we ascertain the frizzled-related gene complement in six lophotrochozoan species, and determine their spatial and temporal expression pattern during early embryogenesis and larval stages of the marine annelid Platynereis dumerilii. Results Phylogenetic analyses confirm conserved homologs for four frizzled receptors (Fz1/2/7, Fz4, Fz5/8, Fz9/10) and sFRP1/2/5 in five of six lophotrochozoan species. The sfrp3/4 gene is conserved in one, divergent in two, and evidently lost in three lophotrochozoan species. Three novel fz-related genes (fzCRD1-3) are unique to Platynereis. Transcriptional profiling and in situ hybridization identified high maternal expression of fz1/2/7, expression of fz9/10 and fz1/2/7 within animal and dorsal cell lineages after the 32-cell stage, localization of fz5/8, sfrp1/2/5, and fzCRD-1 to animal-pole cell lineages after the 80-cell stage, and no expression for fz4, sfrp3/4, and fzCRD-2, and -3 in early Platynereis embryos. In later larval stages, all frizzled-related genes are expressed in distinct patterns preferentially in the anterior hemisphere and less in the developing trunk. Conclusions Lophotrochozoans have retained a generally conserved ancestral bilaterian frizzled-related gene complement (four Fzs and two sFRPs). Maternal expression of fz1/2/7, and animal lineage-specific expression of fz5/8 and sfrp1/2/5 in early embryos of Platynereis suggest evolutionary conserved roles of these genes to perform Wnt pathway functions during early cleavage stages, and the early establishment of a Wnt inhibitory center at the animal pole, respectively. Numerous frizzled receptor-expressing cells and embryonic territories were identified that might indicate competence to receive Wnt signals during annelid development. An anterior bias for frizzled-related gene expression in embryos and larvae might point to a polarity of Wnt patterning systems along the anterior–posterior axis of this annelid. Electronic supplementary material The online version of this article (doi:10.1186/s13227-015-0032-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Benjamin R Bastin
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
| | | | | | - Stephan Q Schneider
- Department of Genetics, Development and Cell Biology, Iowa State University, 503 Science Hall II, Ames, IA 50011 USA
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Zacharias AL, Walton T, Preston E, Murray JI. Quantitative Differences in Nuclear β-catenin and TCF Pattern Embryonic Cells in C. elegans. PLoS Genet 2015; 11:e1005585. [PMID: 26488501 PMCID: PMC4619327 DOI: 10.1371/journal.pgen.1005585] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 09/16/2015] [Indexed: 12/22/2022] Open
Abstract
The Wnt signaling pathway plays a conserved role during animal development in transcriptional regulation of distinct targets in different developmental contexts but it remains unclear whether quantitative differences in the nuclear localization of effector proteins TCF and β-catenin contribute to context-specific regulation. We investigated this question in Caenorhabditis elegans embryos by quantifying nuclear localization of fluorescently tagged SYS-1/β-catenin and POP-1/TCF and expression of Wnt ligands at cellular resolution by time-lapse microscopy and automated lineage tracing. We identified reproducible, quantitative differences that generate a subset of Wnt-signaled cells with a significantly higher nuclear concentration of the TCF/β-catenin activating complex. Specifically, β-catenin and TCF are preferentially enriched in nuclei of daughter cells whose parents also had high nuclear levels of that protein, a pattern that could influence developmental gene expression. Consistent with this, we found that expression of synthetic reporters of POP-1-dependent activation is biased towards cells that had high nuclear SYS-1 in consecutive divisions. We identified new genes whose embryonic expression patterns depend on pop-1. Most of these require POP-1 for either transcriptional activation or repression, and targets requiring POP-1 for activation are more likely to be expressed in the cells with high nuclear SYS-1 in consecutive divisions than those requiring POP-1 for repression. Taken together, these results indicate that SYS-1 and POP-1 levels are influenced by the parent cell’s SYS-1/POP-1 levels and this may provide an additional mechanism by which POP-1 regulates distinct targets in different developmental contexts. The Wnt signaling pathway is active during the development of all multi-cellular animals and also improperly re-activated in many cancers. Here, we use time-lapse microscopy to quantify the nuclear localization of several proteins in response to Wnt signaling throughout early embryonic development in the nematode worm, C. elegans. We find that cells that received a Wnt signal in the previous division respond more strongly to a Wnt signal in the next division, in part by localizing more of the regulator β-catenin to the nucleus. This causes the relative enrichment of Wnt pathway proteins in the nuclei of repeatedly signaled cells, which we show likely impacts the activation of Wnt target genes. This represents a novel mechanism for the regulation of Wnt pathway targets in development and disease.
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Affiliation(s)
- Amanda L. Zacharias
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Travis Walton
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Elicia Preston
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - John Isaac Murray
- Department of Genetics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
- * E-mail:
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Sokol SY. Spatial and temporal aspects of Wnt signaling and planar cell polarity during vertebrate embryonic development. Semin Cell Dev Biol 2015; 42:78-85. [PMID: 25986055 PMCID: PMC4562884 DOI: 10.1016/j.semcdb.2015.05.002] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2015] [Accepted: 05/08/2015] [Indexed: 11/19/2022]
Abstract
Wnt signaling pathways act at multiple locations and developmental stages to specify cell fate and polarity in vertebrate embryos. A long-standing question is how the same molecular machinery can be reused to produce different outcomes. The canonical Wnt/β-catenin branch modulates target gene transcription to specify cell fates along the dorsoventral and anteroposterior embryonic axes. By contrast, the Wnt/planar cell polarity (PCP) branch is responsible for cell polarization along main body axes, which coordinates morphogenetic cell behaviors during gastrulation and neurulation. Whereas both cell fate and cell polarity are modulated by spatially- and temporally-restricted Wnt activity, the downstream signaling mechanisms are very diverse. This review highlights recent progress in the understanding of Wnt-dependent molecular events leading to the establishment of PCP and linking it to early morphogenetic processes.
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Affiliation(s)
- Sergei Y Sokol
- Department of Developmental and Regenerative Biology, Icahn School of Medicine at Mount Sinai, New York, NY 10029, USA.
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McCauley BS, Akyar E, Saad HR, Hinman VF. Dose-dependent nuclear β-catenin response segregates endomesoderm along the sea star primary axis. Development 2015; 142:207-17. [PMID: 25516976 DOI: 10.1242/dev.113043] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In many invertebrates, the nuclearization of β-catenin at one pole of the embryo initiates endomesoderm specification. An intriguing possibility is that a gradient of nuclear β-catenin (nβ-catenin), similar to that operating in vertebrate neural tube patterning, functions to distinguish cell fates in invertebrates. To test this hypothesis, we determined the function of nβ-catenin during the early development of the sea star, which undergoes a basal deuterostomal mode of embryogenesis. We show that low levels of nβ-catenin activity initiate bra, which is expressed in the future posterior endoderm-fated territory; intermediate levels are required for expression of foxa and gata4/5/6, which are later restricted to the endoderm; and activation of ets1 and erg in the mesoderm-fated territory requires the highest nβ-catenin activity. Transcription factors acting downstream of high nβ-catenin segregate the endoderm/mesoderm boundary, which is further reinforced by Delta/Notch signaling. Significantly, therefore, in sea stars, endomesoderm segregation arises through transcriptional responses to levels of nβ-catenin activity. Here, we describe the first empirical evidence of a dose-dependent response to a dynamic spatiotemporal nβ-catenin activity that patterns cell fates along the primary axis in an invertebrate.
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Affiliation(s)
- Brenna S McCauley
- Department of Biological Sciences, Carnegie Mellon University, 4400 5th Ave, Pittsburgh, PA 15213, USA
| | - Eda Akyar
- Department of Biological Sciences, Carnegie Mellon University, 4400 5th Ave, Pittsburgh, PA 15213, USA
| | - H Rosa Saad
- Department of Biological Sciences, Carnegie Mellon University, 4400 5th Ave, Pittsburgh, PA 15213, USA
| | - Veronica F Hinman
- Department of Biological Sciences, Carnegie Mellon University, 4400 5th Ave, Pittsburgh, PA 15213, USA
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Lauri A, Brunet T, Handberg-Thorsager M, Fischer AHL, Simakov O, Steinmetz PRH, Tomer R, Keller PJ, Arendt D. Development of the annelid axochord: insights into notochord evolution. Science 2014; 345:1365-8. [PMID: 25214631 DOI: 10.1126/science.1253396] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The origin of chordates has been debated for more than a century, with one key issue being the emergence of the notochord. In vertebrates, the notochord develops by convergence and extension of the chordamesoderm, a population of midline cells of unique molecular identity. We identify a population of mesodermal cells in a developing invertebrate, the marine annelid Platynereis dumerilii, that converges and extends toward the midline and expresses a notochord-specific combination of genes. These cells differentiate into a longitudinal muscle, the axochord, that is positioned between central nervous system and axial blood vessel and secretes a strong collagenous extracellular matrix. Ancestral state reconstruction suggests that contractile mesodermal midline cells existed in bilaterian ancestors. We propose that these cells, via vacuolization and stiffening, gave rise to the chordate notochord.
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Affiliation(s)
- Antonella Lauri
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg
| | - Thibaut Brunet
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg
| | - Mette Handberg-Thorsager
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg. Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Antje H L Fischer
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg
| | - Oleg Simakov
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg
| | - Patrick R H Steinmetz
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg
| | - Raju Tomer
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg. Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Philipp J Keller
- Janelia Farm Research Campus, 19700 Helix Drive, Ashburn, VA 20147, USA
| | - Detlev Arendt
- Developmental Biology Unit, European Molecular Biology Laboratory (EMBL), D-69117 Heidelberg. Centre for Organismal Studies, University of Heidelberg, Heidelberg, Germany.
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Hüsken U, Stickney HL, Gestri G, Bianco IH, Faro A, Young RM, Roussigne M, Hawkins TA, Beretta CA, Brinkmann I, Paolini A, Jacinto R, Albadri S, Dreosti E, Tsalavouta M, Schwarz Q, Cavodeassi F, Barth AK, Wen L, Zhang B, Blader P, Yaksi E, Poggi L, Zigman M, Lin S, Wilson SW, Carl M. Tcf7l2 is required for left-right asymmetric differentiation of habenular neurons. Curr Biol 2014; 24:2217-27. [PMID: 25201686 PMCID: PMC4194317 DOI: 10.1016/j.cub.2014.08.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 06/11/2014] [Accepted: 08/02/2014] [Indexed: 12/31/2022]
Abstract
BACKGROUND Although left-right asymmetries are common features of nervous systems, their developmental bases are largely unknown. In the zebrafish epithalamus, dorsal habenular neurons adopt medial (dHbm) and lateral (dHbl) subnuclear character at very different frequencies on the left and right sides. The left-sided parapineal promotes the elaboration of dHbl character in the left habenula, albeit by an unknown mechanism. Likewise, the genetic pathways acting within habenular neurons to control their asymmetric differentiated character are unknown. RESULTS In a forward genetic screen for mutations that result in loss of habenular asymmetry, we identified two mutant alleles of tcf7l2, a gene that encodes a transcriptional regulator of Wnt signaling. In tcf7l2 mutants, most neurons on both sides differentiate with dHbl identity. Consequently, the habenulae develop symmetrically, with both sides adopting a pronounced leftward character. Tcf7l2 acts cell automously in nascent equipotential neurons, and on the right side, it promotes dHbm and suppresses dHbl differentiation. On the left, the parapineal prevents this Tcf7l2-dependent process, thereby promoting dHbl differentiation. CONCLUSIONS Tcf7l2 is essential for lateralized fate selection by habenular neurons that can differentiate along two alternative pathways, thereby leading to major neural circuit asymmetries.
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Affiliation(s)
- Ulrike Hüsken
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany
| | - Heather L Stickney
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Gaia Gestri
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Isaac H Bianco
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Ana Faro
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Rodrigo M Young
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Myriam Roussigne
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK; Centre de Biologie du Développement (CDB), UPS, Université de Toulouse, 118 Route de Narbonne, 31062, France; CNRS, CDB UMR 5547, 31062 Toulouse, France
| | - Thomas A Hawkins
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Carlo A Beretta
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany
| | - Irena Brinkmann
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany
| | - Alessio Paolini
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany
| | - Raquel Jacinto
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany
| | - Shahad Albadri
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Elena Dreosti
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK; Neuroelectronics Research Flanders, 3001 Leuven, Belgium
| | - Matina Tsalavouta
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Quenten Schwarz
- Institute of Ophthalmology, University College London, London EC1V 9EL, UK
| | - Florencia Cavodeassi
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Anukampa K Barth
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK
| | - Lu Wen
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China
| | - Bo Zhang
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China
| | - Patrick Blader
- Centre de Biologie du Développement (CDB), UPS, Université de Toulouse, 118 Route de Narbonne, 31062, France; CNRS, CDB UMR 5547, 31062 Toulouse, France
| | - Emre Yaksi
- Neuroelectronics Research Flanders, 3001 Leuven, Belgium; Vlaams Instituut voor Biotechnologie, 3001 Leuven, Belgium; KU Leuven, 3001 Leuven, Belgium
| | - Lucia Poggi
- Centre for Organismal Studies, Heidelberg University, 69120 Heidelberg, Germany
| | - Mihaela Zigman
- Department of Molecular Evolution and Genomics, Centre for Organismal Studies (COS), Heidelberg University, Im Neuenheimer Feld 329, 69120 Heidelberg, Germany
| | - Shuo Lin
- Key Laboratory of Cell Proliferation and Differentiation of the Ministry of Education, College of Life Sciences, Peking University, Beijing 100871, China; Department of Molecular, Cell, and Developmental Biology, University of California, Los Angeles, 621 Charles E. Young Drive, Los Angeles, CA 90095, USA
| | - Stephen W Wilson
- Department of Cell and Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK.
| | - Matthias Carl
- Department of Cell and Molecular Biology, Medical Faculty Mannheim, Heidelberg University, Ludolf-Krehl-Strasse 13-17, 68167 Mannheim, Germany.
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Fischer AHL, Mozzherin D, Eren AM, Lans KD, Wilson N, Cosentino C, Smith J. SeaBase: a multispecies transcriptomic resource and platform for gene network inference. Integr Comp Biol 2014; 54:250-63. [PMID: 24907201 DOI: 10.1093/icb/icu065] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Marine and aquatic animals are extraordinarily useful as models for identifying mechanisms of development and evolution, regeneration, resistance to cancer, longevity and symbiosis, among many other areas of research. This is due to the great diversity of these organisms and their wide-ranging capabilities. Genomics tools are essential for taking advantage of these "free lessons" of nature. However, genomics and transcriptomics are challenging in emerging model systems. Here, we present SeaBase, a tool for helping to meet these needs. Specifically, SeaBase provides a platform for sharing and searching transcriptome data. More importantly, SeaBase will support a growing number of tools for inferring gene network mechanisms. The first dataset available on SeaBase is a developmental transcriptomic profile of the sea anemone Nematostella vectensis (Anthozoa, Cnidaria). Additional datasets are currently being prepared and we are aiming to expand SeaBase to include user-supplied data for any number of marine and aquatic organisms, thereby supporting many potentially new models for gene network studies. SeaBase can be accessed online at: http://seabase.core.cli.mbl.edu.
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Affiliation(s)
- Antje H L Fischer
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy*Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - Dmitry Mozzherin
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - A Murat Eren
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - Kristen D Lans
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - Nathan Wilson
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - Carlo Cosentino
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
| | - Joel Smith
- *Marine Biological Laboratory, Woods Hole, MA 02543, USA; Department of Molecular and Cellular Biology, Harvard University, Cambridge, MA 02138, USA; Systems & Control Engineering, University of Magna Graecia, 88100 Catanzaro, Italy
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Pfeifer K, Schaub C, Domsch K, Dorresteijn A, Wolfstetter G. Maternal inheritance of twist and analysis of MAPK activation in embryos of the polychaete annelid Platynereis dumerilii. PLoS One 2014; 9:e96702. [PMID: 24792484 PMCID: PMC4008618 DOI: 10.1371/journal.pone.0096702] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 04/10/2014] [Indexed: 11/18/2022] Open
Abstract
In this study, we aimed to identify molecular mechanisms involved in the specification of the 4d (mesentoblast) lineage in Platynereis dumerilii. We employ RT-PCR and in situ hybridization against the Platynereis dumerilii twist homolog (Pdu-twist) to reveal mesodermal specification within this lineage. We show that Pdu-twist mRNA is already maternally distributed. After fertilization, ooplasmatic segregation leads to relocation of Pdu-twist transcripts into the somatoblast (2d) lineage and 4d, indicating that the maternal component of Pdu-twist might be an important prerequisite for further mesoderm specification but does not represent a defining characteristic of the mesentoblast. However, after the primordial germ cells have separated from the 4d lineage, zygotic transcription of Pdu-twist is exclusively observed in the myogenic progenitors, suggesting that mesodermal specification occurs after the 4d stage. Previous studies on spiral cleaving embryos revealed a spatio-temporal correlation between the 4d lineage and the activity of an embryonic organizer that is capable to induce the developmental fates of certain micromeres. This has raised the question if specification of the 4d lineage could be connected to the organizer activity. Therefore, we aimed to reveal the existence of such a proposed conserved organizer in Platynereis employing antibody staining against dpERK. In contrast to former observations in other spiralian embryos, activation of MAPK signaling during 2d and 4d formation cannot be detected which questions the existence of a conserved connection between organizer function and specification of the 4d lineage. However, our experiments unveil robust MAPK activation in the prospective nephroblasts as well as in the macromeres and some micromeres at the blastopore in gastrulating embryos. Inhibition of MAPK activation leads to larvae with a shortened body axis, defects in trunk muscle spreading and improper nervous system condensation, indicating a critical function for MAPK signaling for the reorganization of embryonic tissues during the gastrulation process.
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Affiliation(s)
- Kathrin Pfeifer
- Institut für Allgemeine und Spezielle Zoologie; Allgemeine Zoologie und Entwicklungsbiologie, Justus-Liebig-Universität Gieβen, Gieβen, Germany
| | - Christoph Schaub
- Institut für Allgemeine und Spezielle Zoologie; Allgemeine Zoologie und Entwicklungsbiologie, Justus-Liebig-Universität Gieβen, Gieβen, Germany
| | - Katrin Domsch
- Institut für Allgemeine und Spezielle Zoologie; Allgemeine Zoologie und Entwicklungsbiologie, Justus-Liebig-Universität Gieβen, Gieβen, Germany
| | - Adriaan Dorresteijn
- Institut für Allgemeine und Spezielle Zoologie; Allgemeine Zoologie und Entwicklungsbiologie, Justus-Liebig-Universität Gieβen, Gieβen, Germany
| | - Georg Wolfstetter
- Institut für Allgemeine und Spezielle Zoologie; Allgemeine Zoologie und Entwicklungsbiologie, Justus-Liebig-Universität Gieβen, Gieβen, Germany
- * E-mail:
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Zantke J, Bannister S, Rajan VBV, Raible F, Tessmar-Raible K. Genetic and genomic tools for the marine annelid Platynereis dumerilii. Genetics 2014; 197:19-31. [PMID: 24807110 PMCID: PMC4012478 DOI: 10.1534/genetics.112.148254] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Accepted: 02/17/2014] [Indexed: 01/27/2023] Open
Abstract
The bristle worm Platynereis dumerilii displays many interesting biological characteristics. These include its reproductive timing, which is synchronized to the moon phase, its regenerative capacity that is hormonally controlled, and a slow rate of evolution, which permits analyses of ancestral genes and cell types. As a marine annelid, Platynereis is also representative of the marine ecosystem, as well as one of the three large animal subphyla, the Lophotrochozoa. Here, we provide an overview of the molecular resources, functional techniques, and behavioral assays that have recently been established for the bristle worm. This combination of tools now places Platynereis in an excellent position to advance research at the frontiers of neurobiology, chronobiology, evo-devo, and marine biology.
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Affiliation(s)
- Juliane Zantke
- Max F. Perutz Laboratories
- Research Platform Marine Rhythms of Life, University of Vienna 1030 Vienna, Austria
| | - Stephanie Bannister
- Max F. Perutz Laboratories
- Research Platform Marine Rhythms of Life, University of Vienna 1030 Vienna, Austria
| | - Vinoth Babu Veedin Rajan
- Max F. Perutz Laboratories
- Research Platform Marine Rhythms of Life, University of Vienna 1030 Vienna, Austria
| | - Florian Raible
- Max F. Perutz Laboratories
- Research Platform Marine Rhythms of Life, University of Vienna 1030 Vienna, Austria
| | - Kristin Tessmar-Raible
- Max F. Perutz Laboratories
- Research Platform Marine Rhythms of Life, University of Vienna 1030 Vienna, Austria
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TALENs mediate efficient and heritable mutation of endogenous genes in the marine annelid Platynereis dumerilii. Genetics 2014; 197:77-89. [PMID: 24653002 PMCID: PMC4012502 DOI: 10.1534/genetics.113.161091] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Platynereis dumerilii is a marine polychaete and an established model system for studies of evolution and development. Platynereis is also a re-emerging model for studying the molecular basis of circalunar reproductive timing: a biological phenomenon observed in many marine species. While gene expression studies have provided new insight into patterns of gene regulation, a lack of reverse genetic tools has so far limited the depth of functional analyses in this species. To address this need, we established customized transcriptional activator-like effector nucleases (TALENs) as a tool to engineer targeted modifications in Platynereis genes. By adapting a workflow of TALEN construction protocols and mutation screening approaches for use in Platynereis, we engineered frameshift mutations in three endogenous Platynereis genes. We confirmed that such mutations are heritable, demonstrating that TALENs can be used to generate homozygous knockout lines in P. dumerilii. This is the first use of TALENs for generating genetic knockout mutations in an annelid model. These tools not only open the door for detailed in vivo functional analyses, but also can facilitate further technical development, such as targeted genome editing.
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47
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Schlosser G, Patthey C, Shimeld SM. The evolutionary history of vertebrate cranial placodes II. Evolution of ectodermal patterning. Dev Biol 2014; 389:98-119. [PMID: 24491817 DOI: 10.1016/j.ydbio.2014.01.019] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 01/21/2014] [Accepted: 01/24/2014] [Indexed: 12/12/2022]
Abstract
Cranial placodes are evolutionary innovations of vertebrates. However, they most likely evolved by redeployment, rewiring and diversification of preexisting cell types and patterning mechanisms. In the second part of this review we compare vertebrates with other animal groups to elucidate the evolutionary history of ectodermal patterning. We show that several transcription factors have ancient bilaterian roles in dorsoventral and anteroposterior regionalisation of the ectoderm. Evidence from amphioxus suggests that ancestral chordates then concentrated neurosecretory cells in the anteriormost non-neural ectoderm. This anterior proto-placodal domain subsequently gave rise to the oral siphon primordia in tunicates (with neurosecretory cells being lost) and anterior (adenohypophyseal, olfactory, and lens) placodes of vertebrates. Likewise, tunicate atrial siphon primordia and posterior (otic, lateral line, and epibranchial) placodes of vertebrates probably evolved from a posterior proto-placodal region in the tunicate-vertebrate ancestor. Since both siphon primordia in tunicates give rise to sparse populations of sensory cells, both proto-placodal domains probably also gave rise to some sensory receptors in the tunicate-vertebrate ancestor. However, proper cranial placodes, which give rise to high density arrays of specialised sensory receptors and neurons, evolved from these domains only in the vertebrate lineage. We propose that this may have involved rewiring of the regulatory network upstream and downstream of Six1/2 and Six4/5 transcription factors and their Eya family cofactors. These proteins, which play ancient roles in neuronal differentiation were first recruited to the dorsal non-neural ectoderm in the tunicate-vertebrate ancestor but subsequently probably acquired new target genes in the vertebrate lineage, allowing them to adopt new functions in regulating proliferation and patterning of neuronal progenitors.
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Affiliation(s)
- Gerhard Schlosser
- Department of Zoology, School of Natural Sciences & Regenerative Medicine Institute (REMEDI), National University of Ireland, University Road, Galway, Ireland.
| | - Cedric Patthey
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
| | - Sebastian M Shimeld
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
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Marlow H, Tosches MA, Tomer R, Steinmetz PR, Lauri A, Larsson T, Arendt D. Larval body patterning and apical organs are conserved in animal evolution. BMC Biol 2014; 12:7. [PMID: 24476105 PMCID: PMC3939940 DOI: 10.1186/1741-7007-12-7] [Citation(s) in RCA: 137] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Accepted: 01/24/2014] [Indexed: 12/31/2022] Open
Abstract
Background Planktonic ciliated larvae are characteristic for the life cycle of marine invertebrates. Their most prominent feature is the apical organ harboring sensory cells and neurons of largely undetermined function. An elucidation of the relationships between various forms of primary larvae and apical organs is key to understanding the evolution of animal life cycles. These relationships have remained enigmatic due to the scarcity of comparative molecular data. Results To compare apical organs and larval body patterning, we have studied regionalization of the episphere, the upper hemisphere of the trochophore larva of the marine annelid Platynereis dumerilii. We examined the spatial distribution of transcription factors and of Wnt signaling components previously implicated in anterior neural development. Pharmacological activation of Wnt signaling with Gsk3β antagonists abolishes expression of apical markers, consistent with a repressive role of Wnt signaling in the specification of apical tissue. We refer to this Wnt-sensitive, six3- and foxq2-expressing part of the episphere as the ‘apical plate’. We also unraveled a molecular signature of the apical organ - devoid of six3 but expressing foxj, irx, nkx3 and hox - that is shared with other marine phyla including cnidarians. Finally, we characterized the cell types that form part of the apical organ by profiling by image registration, which allows parallel expression profiling of multiple cells. Besides the hox-expressing apical tuft cells, this revealed the presence of putative light- and mechanosensory as well as multiple peptidergic cell types that we compared to apical organ cell types of other animal phyla. Conclusions The similar formation of a six3+, foxq2+ apical plate, sensitive to Wnt activity and with an apical tuft in its six3-free center, is most parsimoniously explained by evolutionary conservation. We propose that a simple apical organ - comprising an apical tuft and a basal plexus innervated by sensory-neurosecretory apical plate cells - was present in the last common ancestors of cnidarians and bilaterians. One of its ancient functions would have been the control of metamorphosis. Various types of apical plate cells would then have subsequently been added to the apical organ in the divergent bilaterian lineages. Our findings support an ancient and common origin of primary ciliated larvae.
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Affiliation(s)
- Heather Marlow
- European Molecular Biology Laboratory, Development Biology Unit, EMBL Heidelberg, Meyerhofstraße 1, 69117 Heidelberg, Germany.
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Lidke AK, Bannister S, Löwer AM, Apel DM, Podleschny M, Kollmann M, Ackermann CF, García-Alonso J, Raible F, Rebscher N. 17β-Estradiol induces supernumerary primordial germ cells in embryos of the polychaete Platynereis dumerilii. Gen Comp Endocrinol 2014; 196:52-61. [PMID: 24287341 DOI: 10.1016/j.ygcen.2013.11.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Revised: 11/01/2013] [Accepted: 11/14/2013] [Indexed: 01/14/2023]
Abstract
In the polychaete Platynereis dumerilii exactly four primordial germ cells (PGCs) arise in early development and are subject to a transient mitotic arrest until the animals enter gametogenesis. In order to unravel the mechanisms controlling the number of PGCs in Platynereis, we tested whether the steroid 17β-estradiol (E2) is able to induce PGC proliferation, as it had been described in other species. Our data provide strong support for such a mechanism, showing that E2 significantly increases the occurrence of larvae with supernumerary PGCs in Platynereis in a dose dependent manner. E2 responsiveness is restricted to early developmental stages, when the PGCs are specified. During these stages, embryos exhibit high expression levels of the estradiol receptor (ER). The ER transcript localizes to the yolk-free cytoplasm of unfertilized eggs and segregates into the micromeres during cleavage stages. Nuclear ER protein is found asymmetrically distributed between daughter cells. Neither transcript nor protein is detectable in PGCs at larval stages. Addition of the specific estradiol receptor inhibitor ICI-182,780 (ICI) abolishes the proliferative effect of E2, suggesting that it is mediated by ER signaling. Our study reports for the first time an ER mediated proliferative effect of E2 on PGCs in an invertebrate organism.
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Affiliation(s)
- Anika K Lidke
- Morphology and Evolution of Invertebrates, Philipps-Universität Marburg, Germany
| | - Stephanie Bannister
- Max F. Perutz Laboratories and Research Platform "Marine Rhythms of Life", University of Vienna, Vienna, Austria
| | - Andreas M Löwer
- Morphology and Evolution of Invertebrates, Philipps-Universität Marburg, Germany
| | - David M Apel
- Morphology and Evolution of Invertebrates, Philipps-Universität Marburg, Germany
| | | | | | | | - Javier García-Alonso
- Biodiversity Group, Centro Universitario Regional Este, Universidad de la República, Maldonado, Uruguay
| | - Florian Raible
- Max F. Perutz Laboratories and Research Platform "Marine Rhythms of Life", University of Vienna, Vienna, Austria
| | - Nicole Rebscher
- Morphology and Evolution of Invertebrates, Philipps-Universität Marburg, Germany.
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Abstract
High and low nuclear levels of the conserved transcriptional regulator β-catenin distinguish multiple sister cell fates to specify endoderm and mesoderm during early embryogenesis in a chordate embryo.
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Affiliation(s)
- Stephan Q Schneider
- Department of Genetics, Development and Cell Biology, 503 Science Hall II, Iowa State University, Ames, IA 50011, USA.
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