1
|
Merle M, Friedman L, Chureau C, Shoushtarizadeh A, Gregor T. Precise and scalable self-organization in mammalian pseudo-embryos. Nat Struct Mol Biol 2024; 31:896-902. [PMID: 38491138 DOI: 10.1038/s41594-024-01251-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2023] [Accepted: 02/08/2024] [Indexed: 03/18/2024]
Abstract
Gene expression is inherently noisy, posing a challenge to understanding how precise and reproducible patterns of gene expression emerge in mammals. Here we investigate this phenomenon using gastruloids, a three-dimensional in vitro model for early mammalian development. Our study reveals intrinsic reproducibility in the self-organization of gastruloids, encompassing growth dynamics and gene expression patterns. We observe a remarkable degree of control over gene expression along the main body axis, with pattern boundaries positioned with single-cell precision. Furthermore, as gastruloids grow, both their physical proportions and gene expression patterns scale proportionally with system size. Notably, these properties emerge spontaneously in self-organizing cell aggregates, distinct from many in vivo systems constrained by fixed boundary conditions. Our findings shed light on the intricacies of developmental precision, reproducibility and size scaling within a mammalian system, suggesting that these phenomena might constitute fundamental features of multicellularity.
Collapse
Affiliation(s)
- Mélody Merle
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Leah Friedman
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Corinne Chureau
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Armin Shoushtarizadeh
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France
| | - Thomas Gregor
- Department of Developmental and Stem Cell Biology, CNRS UMR3738 Paris Cité, Institut Pasteur, Paris, France.
- Joseph Henry Laboratories of Physics & Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, NJ, USA.
| |
Collapse
|
2
|
Saito S, Kanazawa U, Tatsumi A, Iida A, Takemoto T, Suzuki T. Functional analysis of a first hindlimb positioning enhancer via Gdf11 expression. Front Cell Dev Biol 2024; 12:1302141. [PMID: 38559809 PMCID: PMC10978735 DOI: 10.3389/fcell.2024.1302141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 02/22/2024] [Indexed: 04/04/2024] Open
Abstract
During the early development of tetrapods, including humans, the embryonic body elongates caudally once the anterior-posterior axis is established. During this process, region-specific vertebral morphogenesis occurs, with the determination of limb positioning along the anterior-posterior axis. We previously reported that Gdf11 functions as an anatomical integration system that determines the positioning of hindlimbs and sacral vertebrae where Gdf11 is expressed. However, the molecular mechanisms underlying induction of Gdf11 expression remain unclear. In this study, we searched for non-coding regions near the Gdf11 locus that were conserved across species to elucidate the regulatory mechanisms of Gdf11 expression. We identified an enhancer of the Gdf11 gene in intron 1 and named it highly conserved region (HCR). In HCR knockout mice, the expression level of endogenous Gdf11 was decreased, and the position of the sacral-hindlimb unit was shifted posteriorly. We also searched for factors upstream of Gdf11 based on the predicted transcription factor binding sites within the HCR. We found that inhibition of FGF signaling increased endogenous Gdf11 expression, suggesting that FGF signaling negatively regulates Gdf11 expression. However, FGF signaling does not regulate HCR activity. Our results suggest that there are species-specific Gdf11 enhancers other than HCR and that FGF signaling regulates Gdf11 expression independent of HCR.
Collapse
Affiliation(s)
- Seiji Saito
- Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Utsugi Kanazawa
- Division of Biological Science, Graduate School of Science, Nagoya University, Nagoya, Japan
| | - Ayana Tatsumi
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, Osaka, Japan
| | - Atsuo Iida
- Department of Animal Sciences, Graduate School of Bioagricultural Sciences, Nagoya University, Furo-cho, Chikusa-ku, Nagoya, Japan
| | - Tatsuya Takemoto
- Institute for Advanced Medical Sciences, Tokushima University, Tokushima, Japan
| | - Takayuki Suzuki
- Department of Biology, Graduate School of Science, Osaka Metropolitan University, Osaka, Japan
| |
Collapse
|
3
|
Schnirman RE, Kuo SJ, Kelly RC, Yamaguchi TP. The role of Wnt signaling in the development of the epiblast and axial progenitors. Curr Top Dev Biol 2023; 153:145-180. [PMID: 36967193 DOI: 10.1016/bs.ctdb.2023.01.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
Understanding how the body plan is established during embryogenesis remains a fundamental biological question. The Wnt/β-catenin signaling pathway plays a crucial and highly conserved role in body plan formation, functioning to polarize the primary anterior-posterior (AP) or head-to-tail body axis in most metazoans. In this chapter, we focus on the roles that the mammalian Wnt/β-catenin pathway plays to prepare the pluripotent epiblast for gastrulation, and to elicit the emergence of multipotent axial progenitors from the caudal epiblast. Interactions between Wnt and retinoic acid (RA), another powerful family of developmental signaling molecules, in axial progenitors will also be discussed. Gastrulation movements and somitogenesis result in the anterior displacement of the RA source (the rostral somites and lateral plate mesoderm (LPM)), from the posterior Wnt source (the primitive streak (PS)), leading to the establishment of antiparallel gradients of RA and Wnt that control the self-renewal and successive differentiation of neck, trunk and tail progenitors.
Collapse
Affiliation(s)
| | - Samuel J Kuo
- NCI-Frederick, NIH, Frederick, MD, United States
| | - Ryan C Kelly
- NCI-Frederick, NIH, Frederick, MD, United States
| | | |
Collapse
|
4
|
López-Anguita N, Gassaloglu SI, Stötzel M, Bolondi A, Conkar D, Typou M, Buschow R, Veenvliet JV, Bulut-Karslioglu A. Hypoxia induces an early primitive streak signature, enhancing spontaneous elongation and lineage representation in gastruloids. Development 2022; 149:dev200679. [PMID: 36102628 PMCID: PMC9578691 DOI: 10.1242/dev.200679] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 08/03/2022] [Indexed: 11/20/2022]
Abstract
The cellular microenvironment, together with intrinsic regulators, shapes stem cell identity and differentiation capacity. Mammalian early embryos are exposed to hypoxia in vivo and appear to benefit from hypoxic culture in vitro. Yet, how hypoxia influences stem cell transcriptional networks and lineage choices remain poorly understood. Here, we investigated the molecular effects of acute and prolonged hypoxia on embryonic and extra-embryonic stem cells as well as the functional impact on differentiation potential. We find a temporal and cell type-specific transcriptional response including an early primitive streak signature in hypoxic embryonic stem cells mediated by HIF1α. Using a 3D gastruloid differentiation model, we show that hypoxia-induced T expression enables symmetry breaking and axial elongation in the absence of exogenous WNT activation. When combined with exogenous WNT activation, hypoxia enhances lineage representation in gastruloids, as demonstrated by highly enriched signatures of gut endoderm, notochord, neuromesodermal progenitors and somites. Our findings directly link the microenvironment to stem cell function and provide a rationale supportive of applying physiological conditions in models of embryo development.
Collapse
Affiliation(s)
- Natalia López-Anguita
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- Institute of Chemistry and Biochemistry, Department of Biology, Chemistry and Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Seher Ipek Gassaloglu
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- Stembryogenesis Lab, Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Maximilian Stötzel
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- Institute of Chemistry and Biochemistry, Department of Biology, Chemistry and Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Adriano Bolondi
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- Institute of Chemistry and Biochemistry, Department of Biology, Chemistry and Pharmacy, Freie Universität Berlin, 14195 Berlin, Germany
| | - Deniz Conkar
- Stembryogenesis Lab, Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
| | - Marina Typou
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
- Medical School, Democritus University of Thrace, 681 00 Alexandroupoli, Greece
- Department of Biomedical Sciences, International Hellenic University, 570 01, Thessaloniki, Greece
| | - René Buschow
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| | - Jesse V. Veenvliet
- Stembryogenesis Lab, Max Planck Institute of Molecular Cell Biology and Genetics, 01307 Dresden, Germany
- Cluster of Excellence Physics of Life, Technische Universität Dresden, 01307 Dresden, Germany
| | - Aydan Bulut-Karslioglu
- Department of Genome Regulation, Max Planck Institute for Molecular Genetics, 14195 Berlin, Germany
| |
Collapse
|
5
|
Cheng K, Seita Y, Moriwaki T, Noshiro K, Sakata Y, Hwang YS, Torigoe T, Saitou M, Tsuchiya H, Iwatani C, Hosaka M, Ohkouchi T, Watari H, Umazume T, Sasaki K. The developmental origin and the specification of the adrenal cortex in humans and cynomolgus monkeys. SCIENCE ADVANCES 2022; 8:eabn8485. [PMID: 35442744 PMCID: PMC9020778 DOI: 10.1126/sciadv.abn8485] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Development of the adrenal cortex, a vital endocrine organ, originates in the adrenogonadal primordium, a common progenitor for both the adrenocortical and gonadal lineages in rodents. In contrast, we find that in humans and cynomolgus monkeys, the adrenocortical lineage originates in a temporally and spatially distinct fashion from the gonadal lineage, arising earlier and more anteriorly within the coelomic epithelium. The adrenal primordium arises from adrenogenic coelomic epithelium via an epithelial-to-mesenchymal transition, which then progresses into the steroidogenic fetal zone via both direct and indirect routes. Notably, we find that adrenocortical and gonadal lineages exhibit distinct HOX codes, suggesting distinct anterior-posterior regionalization. Together, our assessment of the early divergence of these lineages provides a molecular framework for understanding human adrenal and gonadal disorders.
Collapse
Affiliation(s)
- Keren Cheng
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yasunari Seita
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Bell Research Center for Reproductive Health and Cancer, Nagoya 460-0003, Japan
| | - Taku Moriwaki
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Kiwamu Noshiro
- Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Yuka Sakata
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Young Sun Hwang
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Toshihiko Torigoe
- Department of Pathology, Sapporo Medical University Graduate School of Medicine, Sapporo 060-8556, Japan
| | - Mitinori Saitou
- Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan
- Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan
| | - Hideaki Tsuchiya
- Research Center for Animal Life Science, Shiga University of Medical Science, Otsu 520-2192, Japan
| | - Chizuru Iwatani
- Research Center for Animal Life Science, Shiga University of Medical Science, Otsu 520-2192, Japan
| | - Masayoshi Hosaka
- Fukuzumi Obstetrics and Gynecology Hospital, Sapporo 062-0043, Japan
| | | | - Hidemichi Watari
- Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Takeshi Umazume
- Department of Obstetrics and Gynecology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan
| | - Kotaro Sasaki
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Corresponding author.
| |
Collapse
|
6
|
Sasaki K, Oguchi A, Cheng K, Murakawa Y, Okamoto I, Ohta H, Yabuta Y, Iwatani C, Tsuchiya H, Yamamoto T, Seita Y, Saitou M. The embryonic ontogeny of the gonadal somatic cells in mice and monkeys. Cell Rep 2021; 35:109075. [PMID: 33951437 DOI: 10.1016/j.celrep.2021.109075] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/21/2021] [Accepted: 04/12/2021] [Indexed: 12/31/2022] Open
Abstract
In the early fetal stage, the gonads are bipotent and only later become the ovary or testis, depending on the genetic sex. Despite many studies examining how sex determination occurs from biopotential gonads, the spatial and temporal organization of bipotential gonads and their progenitors is poorly understood. Here, using lineage tracing in mice, we find that the gonads originate from a T+ primitive streak through WT1+ posterior intermediate mesoderm and appear to share origins anteriorly with the adrenal glands and posteriorly with the metanephric mesenchyme. Comparative single-cell transcriptomic analyses in mouse and cynomolgus monkey embryos reveal the convergence of the lineage trajectory and genetic programs accompanying the specification of biopotential gonadal progenitor cells. This process involves sustained expression of epithelial genes and upregulation of mesenchymal genes, thereby conferring an epithelial-mesenchymal hybrid state. Our study provides key resources for understanding early gonadogenesis in mice and primates.
Collapse
Affiliation(s)
- Kotaro Sasaki
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA.
| | - Akiko Oguchi
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan; Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan
| | - Keren Cheng
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yasuhiro Murakawa
- RIKEN Center for Integrative Medical Sciences, Yokohama, Kanagawa 230-0045, Japan; Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan
| | - Ikuhiro Okamoto
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Hiroshi Ohta
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Yukihiro Yabuta
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
| | - Chizuru Iwatani
- Research Center for Animal Life Science, Shiga University of Medical Science, Otsu, Shiga 520-2192, Japan
| | - Hideaki Tsuchiya
- Research Center for Animal Life Science, Shiga University of Medical Science, Otsu, Shiga 520-2192, Japan
| | - Takuya Yamamoto
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan; AMED-CREST, AMED, Tokyo 100-0004, Japan; Medical-risk Avoidance based on iPS Cells Team, RIKEN Center for Advanced Intelligence Project (AIP), Kyoto 606-8507, Japan
| | - Yasunari Seita
- Institute for Regenerative Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA; Bell Research Center for Reproductive Health and Cancer, Nagoya 460-0003, Japan
| | - Mitinori Saitou
- Institute for the Advanced Study of Human Biology (ASHBi), Kyoto University, Kyoto 606-8501, Japan; Department of Anatomy and Cell Biology, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan; Center for iPS Cell Research and Application (CiRA), Kyoto University, Kyoto 606-8507, Japan.
| |
Collapse
|
7
|
Abstract
In this review, we consider transformations of axial symmetry in metazoan evolution and development, the genetic basis, and phenotypic expressions of different axial body plans. In addition to the main symmetry types in metazoan body plans, such as rotation (radial symmetry), reflection (mirror and glide reflection symmetry), and translation (metamerism), many biological objects show scale (fractal) symmetry as well as some symmetry-type combinations. Some genetic mechanisms of axial pattern establishment, creating a coordinate system of a metazoan body plan, bilaterian segmentation, and left–right symmetry/asymmetry, are analysed. Data on the crucial contribution of coupled functions of the Wnt, BMP, Notch, and Hedgehog signaling pathways (all pathways are designated according to the abbreviated or full names of genes or their protein products; for details, see below) and the axial Hox-code in the formation and maintenance of metazoan body plans are necessary for an understanding of the evolutionary diversification and phenotypic expression of various types of axial symmetry. The lost body plans of some extinct Ediacaran and early Cambrian metazoans are also considered in comparison with axial body plans and posterior growth in living animals.
Collapse
|
8
|
Veenvliet JV, Herrmann BG. Modeling mammalian trunk development in a dish. Dev Biol 2020; 474:5-15. [PMID: 33347872 DOI: 10.1016/j.ydbio.2020.12.015] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 12/04/2020] [Accepted: 12/13/2020] [Indexed: 12/17/2022]
Abstract
Mammalian post-implantation development comprises the coordination of complex lineage decisions and morphogenetic processes shaping the embryo. Despite technological advances, a comprehensive understanding of the dynamics of these processes and of the self-organization capabilities of stem cells and their descendants remains elusive. Building synthetic embryo-like structures from pluripotent embryonic stem cells in vitro promises to fill these knowledge gaps and thereby may prove transformative for developmental biology. Initial efforts to model the post-implantation embryo resulted in structures with compromised morphology (gastruloids). Recent approaches employing modified culture media, an extracellular matrix surrogate or extra-embryonic stem cells, however, succeeded in establishing embryo-like architecture. For example, embedding of gastruloids in Matrigel unlocked self-organization into trunk-like structures with bilateral somites and a neural tube-like structure, together with gut tissue and primordial germ cell-like cells. In this review, we describe the currently available models, discuss how these can be employed to acquire novel biological insights, and detail the imminent challenges for improving current models by in vitro engineering.
Collapse
Affiliation(s)
- Jesse V Veenvliet
- Dept. of Developmental Genetics, Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, 14195, Berlin, Germany
| | - Bernhard G Herrmann
- Dept. of Developmental Genetics, Max Planck Institute for Molecular Genetics, Ihnestrasse 63-73, 14195, Berlin, Germany; Institute for Medical Genetics, Charité - University Medicine Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203, Berlin, Germany.
| |
Collapse
|
9
|
Singh PB, Belyakin SN, Laktionov PP. Biology and Physics of Heterochromatin- Like Domains/Complexes. Cells 2020; 9:E1881. [PMID: 32796726 PMCID: PMC7465696 DOI: 10.3390/cells9081881] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 07/29/2020] [Accepted: 08/04/2020] [Indexed: 11/17/2022] Open
Abstract
The hallmarks of constitutive heterochromatin, HP1 and H3K9me2/3, assemble heterochromatin-like domains/complexes outside canonical constitutively heterochromatic territories where they regulate chromatin template-dependent processes. Domains are more than 100 kb in size; complexes less than 100 kb. They are present in the genomes of organisms ranging from fission yeast to human, with an expansion in size and number in mammals. Some of the likely functions of domains/complexes include silencing of the donor mating type region in fission yeast, preservation of DNA methylation at imprinted germline differentially methylated regions (gDMRs) and regulation of the phylotypic progression during vertebrate development. Far cis- and trans-contacts between micro-phase separated domains/complexes in mammalian nuclei contribute to the emergence of epigenetic compartmental domains (ECDs) detected in Hi-C maps. A thermodynamic description of micro-phase separation of heterochromatin-like domains/complexes may require a gestalt shift away from the monomer as the "unit of incompatibility" that determines the sign and magnitude of the Flory-Huggins parameter, χ. Instead, a more dynamic structure, the oligo-nucleosomal "clutch", consisting of between 2 and 10 nucleosomes is both the long sought-after secondary structure of chromatin and its unit of incompatibility. Based on this assumption we present a simple theoretical framework that enables an estimation of χ for domains/complexes flanked by euchromatin and thereby an indication of their tendency to phase separate. The degree of phase separation is specified by χN, where N is the number of "clutches" in a domain/complex. Our approach could provide an additional tool for understanding the biophysics of the 3D genome.
Collapse
Affiliation(s)
- Prim B. Singh
- Nazarbayev University School of Medicine, Nur-Sultan City 010000, Kazakhstan
- Epigenetics Laboratory, Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
| | - Stepan N. Belyakin
- Epigenetics Laboratory, Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
- Genomics laboratory, Institute of molecular and cellular biology SD RAS, Lavrentyev ave, 8/2, 630090 Novosibirsk, Russia; (S.N.B.); (P.P.L.)
| | - Petr P. Laktionov
- Epigenetics Laboratory, Department of Natural Sciences, Novosibirsk State University, 2 Pirogova St., 630090 Novosibirsk, Russia
- Genomics laboratory, Institute of molecular and cellular biology SD RAS, Lavrentyev ave, 8/2, 630090 Novosibirsk, Russia; (S.N.B.); (P.P.L.)
| |
Collapse
|
10
|
Can H, Chanumolu SK, Gonzalez-Muñoz E, Prukudom S, Otu HH, Cibelli JB. Comparative analysis of single-cell transcriptomics in human and Zebrafish oocytes. BMC Genomics 2020; 21:471. [PMID: 32640983 PMCID: PMC7346435 DOI: 10.1186/s12864-020-06860-z] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 06/22/2020] [Indexed: 02/07/2023] Open
Abstract
Background Zebrafish is a popular model organism, which is widely used in developmental biology research. Despite its general use, the direct comparison of the zebrafish and human oocyte transcriptomes has not been well studied. It is significant to see if the similarity observed between the two organisms at the gene sequence level is also observed at the expression level in key cell types such as the oocyte. Results We performed single-cell RNA-seq of the zebrafish oocyte and compared it with two studies that have performed single-cell RNA-seq of the human oocyte. We carried out a comparative analysis of genes expressed in the oocyte and genes highly expressed in the oocyte across the three studies. Overall, we found high consistency between the human studies and high concordance in expression for the orthologous genes in the two organisms. According to the Ensembl database, about 60% of the human protein coding genes are orthologous to the zebrafish genes. Our results showed that a higher percentage of the genes that are highly expressed in both organisms show orthology compared to the lower expressed genes. Systems biology analysis of the genes highly expressed in the three studies showed significant overlap of the enriched pathways and GO terms. Moreover, orthologous genes that are commonly overexpressed in both organisms were involved in biological mechanisms that are functionally essential to the oocyte. Conclusions Orthologous genes are concurrently highly expressed in the oocytes of the two organisms and these genes belong to similar functional categories. Our results provide evidence that zebrafish could serve as a valid model organism to study the oocyte with direct implications in human.
Collapse
Affiliation(s)
- Handan Can
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Sree K Chanumolu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA
| | - Elena Gonzalez-Muñoz
- LARCEL, Andalusian Laboratory of Cell Reprogramming (LARCel), Andalusian Center for Nanomedicine and Biotechnology-BIONAND, 29590, Málaga, Spain.,Department of Cell Biology, Genetics and Physiology, University of Málaga and; Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, (CIBER-BBNE), 29071, Málaga, Spain
| | - Sukumal Prukudom
- Department of Anatomy, Faculty of Veterinary Medicine, Kasetsart University, Bangkok, 10900, Thailand
| | - Hasan H Otu
- Department of Electrical and Computer Engineering, University of Nebraska-Lincoln, Lincoln, NE, 68588, USA.
| | - Jose B Cibelli
- Departments of Animal Science and Large Animal Clinical Sciences, Michigan State University, East Lansing, MI, 48824, USA.
| |
Collapse
|
11
|
Saito S, Suzuki T. How do signaling and transcription factors regulate both axis elongation and Hox gene expression along the anteroposterior axis? Dev Growth Differ 2020; 62:363-375. [DOI: 10.1111/dgd.12682] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 05/12/2020] [Accepted: 05/15/2020] [Indexed: 01/20/2023]
Affiliation(s)
- Seiji Saito
- Division of Biological Science Graduate School of Science Nagoya University Nagoya Japan
| | - Takayuki Suzuki
- Avian Bioscience Research Center Graduate School of Bioagricultural Sciences Nagoya University Nagoya Japan
| |
Collapse
|
12
|
Severe head dysgenesis resulting from imbalance between anterior and posterior ontogenetic programs. Cell Death Dis 2019; 10:812. [PMID: 31649239 PMCID: PMC6813351 DOI: 10.1038/s41419-019-2040-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Revised: 09/27/2019] [Accepted: 10/03/2019] [Indexed: 12/16/2022]
Abstract
Head dysgenesis is a major cause of fetal demise and craniofacial malformation. Although mutations in genes of the head ontogenetic program have been reported, many cases remain unexplained. Head dysgenesis has also been related to trisomy or amplification of the chromosomal region overlapping the CDX2 homeobox gene, a master element of the trunk ontogenetic program. Hence, we investigated the repercussion on head morphogenesis of the imbalance between the head and trunk ontogenetic programs, by means of ectopic rostral expression of CDX2 at gastrulation. This caused severe malformations affecting the forebrain and optic structures, and also the frontonasal process associated with defects in neural crest cells colonization. These malformations are the result of the downregulation of genes of the head program together with the abnormal induction of trunk program genes. Together, these data indicate that the imbalance between the anterior and posterior ontogenetic programs in embryos is a new possible cause of head dysgenesis during human development, linked to defects in setting up anterior neuroectodermal structures.
Collapse
|
13
|
Kavouras M, Malandrakis EE, Golomazou E, Konstantinidis I, Blom E, Palstra AP, Anastassiadis K, Panagiotaki P, Exadactylos A. Hox gene expression profiles during embryonic development of common sole. ANIM BIOL 2019. [DOI: 10.1163/15707563-17000123] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Common sole (Solea solea) aquaculture production is based mostly on wild-caught breeders. Recently, the successful reproduction of first-generation fish that were reared in captivity was accomplished. A consistent good quality and quantity of produced eggs throughout the year, and of next-generation broodstock, is important for reducing the overall cost of production. Hox genes play a pivotal role in normal embryonic development and alterations of their temporal expression level may be important for egg viability. Expression profile analysis of five hox genes (hoxa1a, hoxa2a, hoxa2b, hoxb1a and hoxb1b) involved in early embryonic development and of hoxa13a, which is involved in late stages, was carried out. Results revealed a premature and/or maternal expression of hoxa13a in sole embryos, and the detection of hoxa2a and hoxa2b genes as members of paralog group 2. Principal Component Analysis of hox gene expression in 54 ± 6 hours post fertilization embryos coming from wild-caught broodstock and a first-generation one reared in the hatchery, unveiled that these broodstocks are clearly distinct. In addition, their pairwise comparison revealed significant differences in the expression levels of hoxb1a and hoxb1b genes. Hox gene regulation during embryonic development could give valuable insight into rearing sole broodstocks with different origin in concert, and also into gaining a steady mass production of eggs, either in quality or quantity, all year round.
Collapse
Affiliation(s)
- Menelaos Kavouras
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| | - Emmanouil E. Malandrakis
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| | - Eleni Golomazou
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| | - Ioannis Konstantinidis
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| | - Ewout Blom
- 2Wageningen Marine Research, Wageningen University & Research, IJmuiden, The Netherlands
| | - Arjan P. Palstra
- 3Wageningen University & Research, Animal Breeding and Genomics, Wageningen Livestock Research, Wageningen, The Netherlands
| | | | - Panagiota Panagiotaki
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| | - Athanasios Exadactylos
- 1Department of Ichthyology and Aquatic Environment, School of Agricultural Sciences, University of Thessaly, Fytokou Str., Volos, Greece
| |
Collapse
|
14
|
Rodrigo Albors A, Halley PA, Storey KG. Lineage tracing of axial progenitors using Nkx1-2CreER T2 mice defines their trunk and tail contributions. Development 2018; 145:dev.164319. [PMID: 30201686 PMCID: PMC6198475 DOI: 10.1242/dev.164319] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2018] [Accepted: 09/03/2018] [Indexed: 12/13/2022]
Abstract
The vertebrate body forms by continuous generation of new tissue from progenitors at the posterior end of the embryo. The study of these axial progenitors has proved to be challenging in vivo largely because of the lack of unique molecular markers to identify them. Here, we elucidate the expression pattern of the transcription factor Nkx1-2 in the mouse embryo and show that it identifies axial progenitors throughout body axis elongation, including neuromesodermal progenitors and early neural and mesodermal progenitors. We create a tamoxifen-inducible Nkx1-2CreERT2 transgenic mouse and exploit the conditional nature of this line to uncover the lineage contributions of Nkx1-2-expressing cells at specific stages. We show that early Nkx1-2-expressing epiblast cells contribute to all three germ layers, mostly neuroectoderm and mesoderm, excluding notochord. Our data are consistent with the presence of some self-renewing axial progenitors that continue to generate neural and mesoderm tissues from the tail bud. This study identifies Nkx1-2-expressing cells as the source of most trunk and tail tissues in the mouse and provides a useful tool to genetically label and manipulate axial progenitors in vivo. Summary: Changing lineage contributions of axial progenitors to the developing mouse embryo are revealed using a tamoxifen-inducible Cre line under the control of the endogenous Nkx1-2 promoter.
Collapse
Affiliation(s)
- Aida Rodrigo Albors
- Neural Development Group, Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Pamela A Halley
- Neural Development Group, Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Kate G Storey
- Neural Development Group, Division of Cell and Developmental Biology, School of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| |
Collapse
|
15
|
Davidson AJ, Lewis P, Przepiorski A, Sander V. Turning mesoderm into kidney. Semin Cell Dev Biol 2018; 91:86-93. [PMID: 30172050 DOI: 10.1016/j.semcdb.2018.08.016] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Revised: 08/24/2018] [Accepted: 08/28/2018] [Indexed: 02/07/2023]
Abstract
The intermediate mesoderm is located between the somites and the lateral plate mesoderm and gives rise to renal progenitors that contribute to the three mammalian kidney types (pronephros, mesonephros and metanephros). In this review, focusing largely on murine kidney development, we examine how the intermediate mesoderm forms during gastrulation/axis elongation and how it progressively gives rise to distinct renal progenitors along the rostro-caudal axis. We highlight some of the potential signalling cues and core transcription factor circuits that direct these processes, up to the point of early metanephric kidney formation.
Collapse
Affiliation(s)
- Alan J Davidson
- Department of Molecular Medicine & Pathology, School of Medical Sciences, Faculty of Medical & Health Sciences, The University of Auckland, Private Bag 921019, Auckland 1142, New Zealand.
| | - Paula Lewis
- Department of Molecular Medicine & Pathology, School of Medical Sciences, Faculty of Medical & Health Sciences, The University of Auckland, Private Bag 921019, Auckland 1142, New Zealand
| | - Aneta Przepiorski
- Department of Molecular Medicine & Pathology, School of Medical Sciences, Faculty of Medical & Health Sciences, The University of Auckland, Private Bag 921019, Auckland 1142, New Zealand
| | - Veronika Sander
- Department of Molecular Medicine & Pathology, School of Medical Sciences, Faculty of Medical & Health Sciences, The University of Auckland, Private Bag 921019, Auckland 1142, New Zealand
| |
Collapse
|
16
|
Abstract
Collinear regulation of Hox genes in space and time has been an outstanding question ever since the initial work of Ed Lewis in 1978. Here we discuss recent advances in our understanding of this phenomenon in relation to novel concepts associated with large-scale regulation and chromatin structure during the development of both axial and limb patterns. We further discuss how this sequential transcriptional activation marks embryonic stem cell-like axial progenitors in mammals and, consequently, how a temporal genetic system is further translated into spatial coordinates via the fate of these progenitors. In this context, we argue the benefit and necessity of implementing this unique mechanism as well as the difficulty in evolving an alternative strategy to deliver this critical positional information.
Collapse
Affiliation(s)
- Jacqueline Deschamps
- Hubrecht Institute, University Medical Center Utrecht, 3584 CT Utrecht, the Netherlands
| | - Denis Duboule
- School of Life Sciences, Ecole Polytechnique Fédérale, Lausanne, 1015 Lausanne, Switzerland.,Department of Genetics and Evolution, University of Geneva, 1211 Geneva 4, Switzerland
| |
Collapse
|
17
|
Rabouille C, Deschamps J. On the shoulders of Hubrecht: From embryos to stem cells. Dev Biol 2017; 428:264-272. [PMID: 27765265 DOI: 10.1016/j.ydbio.2016.10.005] [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: 08/22/2016] [Revised: 10/04/2016] [Accepted: 10/04/2016] [Indexed: 10/20/2022]
Abstract
One hundred years of the Hubrecht Institute were celebrated in May 2016 with the organization of a one-day symposium "From embryos to stem cells" on the Uithof Campus, Utrecht, the Netherlands. Nine distinguished speakers were invited. They all represent a research branch originating from the passion of Institute founder, Ambrosius Hubrecht, for embryology:, regulation of gene expression, genome structure and function, embryonic and adult stem cells, nuclear reprogramming, and understanding cancer and other diseases using model organisms. The centennial symposium not only retraced the history of the Institute and of modern developmental biology, but was also a tribute to basic research. From there, avenues to therapeutics are being developed and implemented. The symposium was organized, introduced and chaired by Jeroen den Hertog and Alexander van Oudenaarden, the present Directors of the Institute, who also stand on Hubrecht's shoulders.
Collapse
Affiliation(s)
- Catherine Rabouille
- Hubrecht Institute - Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) and University Medical Center Utrecht, Upsalalaan 8, 3584 CT Utrecht, The Netherlands.
| | - Jacqueline Deschamps
- Hubrecht Institute - Koninklijke Nederlandse Akademie van Wetenschappen (KNAW) and University Medical Center Utrecht, Upsalalaan 8, 3584 CT Utrecht, The Netherlands.
| |
Collapse
|
18
|
Neijts R, Deschamps J. At the base of colinear Hox gene expression: cis -features and trans -factors orchestrating the initial phase of Hox cluster activation. Dev Biol 2017; 428:293-299. [DOI: 10.1016/j.ydbio.2017.02.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Accepted: 02/16/2017] [Indexed: 10/19/2022]
|
19
|
Sharma R, Shafer MER, Bareke E, Tremblay M, Majewski J, Bouchard M. Bmp signaling maintains a mesoderm progenitor cell state in the mouse tailbud. Development 2017; 144:2982-2993. [PMID: 28705896 DOI: 10.1242/dev.149955] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Accepted: 07/10/2017] [Indexed: 02/01/2023]
Abstract
Caudal somites are generated from a pool of progenitor cells located in the tailbud region. These progenitor cells form the presomitic mesoderm that gradually differentiates into somites under the action of the segmentation clock. The signals responsible for tailbud mesoderm progenitor pool maintenance during axial elongation are still elusive. Here, we show that Bmp signaling is sufficient to activate the entire mesoderm progenitor gene signature in primary cultures of caudal mesoderm cells. Bmp signaling acts through the key regulatory genes brachyury (T) and Nkx1-2 and contributes to the activation of several other regulators of the mesoderm progenitor gene network. In the absence of Bmp signaling, tailbud mesoderm progenitor cells acquire aberrant gene expression signatures of the heart, blood, muscle and skeletal embryonic lineages. Treatment of embryos with the Bmp inhibitor noggin confirmed the requirement for Bmp signaling for normal T expression and the prevention of abnormal lineage marker activation. Together, these results identify Bmp signaling as a non-cell-autonomous signal necessary for mesoderm progenitor cell homeostasis.
Collapse
Affiliation(s)
- Richa Sharma
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Canada H3A 1A3
| | - Maxwell E R Shafer
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Canada H3A 1A3
| | - Eric Bareke
- Department of Human Genetics, McGill University and Genome Quebec Innovation Centre, Montreal, Canada H3A 0G1
| | - Mathieu Tremblay
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Canada H3A 1A3
| | - Jacek Majewski
- Department of Human Genetics, McGill University and Genome Quebec Innovation Centre, Montreal, Canada H3A 0G1
| | - Maxime Bouchard
- Goodman Cancer Research Centre and Department of Biochemistry, McGill University, Montreal, Canada H3A 1A3
| |
Collapse
|
20
|
Gouti M, Delile J, Stamataki D, Wymeersch FJ, Huang Y, Kleinjung J, Wilson V, Briscoe J. A Gene Regulatory Network Balances Neural and Mesoderm Specification during Vertebrate Trunk Development. Dev Cell 2017; 41:243-261.e7. [PMID: 28457792 PMCID: PMC5425255 DOI: 10.1016/j.devcel.2017.04.002] [Citation(s) in RCA: 141] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Revised: 02/20/2017] [Accepted: 04/03/2017] [Indexed: 01/02/2023]
Abstract
Transcriptional networks, regulated by extracellular signals, control cell fate decisions and determine the size and composition of developing tissues. One example is the network controlling bipotent neuromesodermal progenitors (NMPs) that fuel embryo elongation by generating spinal cord and trunk mesoderm tissue. Here, we use single-cell transcriptomics to identify the molecular signature of NMPs and reverse engineer the mechanism that regulates their differentiation. Together with genetic perturbations, this reveals a transcriptional network that integrates opposing retinoic acid (RA) and Wnt signals to determine the rate at which cells enter and exit the NMP state. RA, produced by newly generated mesodermal cells, provides feedback that initiates NMP generation and induces neural differentiation, thereby coordinating the production of neural and mesodermal tissue. Together, the data define a regulatory network architecture that balances the generation of different cell types from bipotential progenitors in order to facilitate orderly axis elongation. Single-cell RNA-seq reveals a signature of neuromesodermal progenitors In vitro NMPs resemble and differentiate similar to their in vivo counterparts Dual role for retinoic acid signaling in NMP induction and neural differentiation A transcriptional network regulates neural versus mesodermal allocation
Collapse
Affiliation(s)
- Mina Gouti
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK; Max Delbrück Center for Molecular Medicine, Robert-Rössle-Strasse 10, 13125 Berlin, Germany.
| | - Julien Delile
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | | | - Filip J Wymeersch
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Yali Huang
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - Jens Kleinjung
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK
| | - Valerie Wilson
- MRC Centre for Regenerative Medicine, Institute for Stem Cell Research, School of Biological Sciences, University of Edinburgh, 5 Little France Drive, Edinburgh EH16 4UU, UK
| | - James Briscoe
- The Francis Crick Institute, 1 Midland Road, London, NW1 1AT, UK.
| |
Collapse
|
21
|
Lee LMY, Leung MBW, Kwok RCY, Leung YC, Wang CC, McCaffery PJ, Copp AJ, Shum ASW. Perturbation of Retinoid Homeostasis Increases Malformation Risk in Embryos Exposed to Pregestational Diabetes. Diabetes 2017; 66:1041-1051. [PMID: 28087565 PMCID: PMC5365142 DOI: 10.2337/db15-1570] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 01/10/2017] [Indexed: 01/07/2023]
Abstract
Pregestational diabetes is highly associated with an increased risk of birth defects. However, factors that can increase or reduce the expressivity and penetrance of malformations in pregnancies in women with diabetes remain poorly identified. All-trans retinoic acid (RA) plays crucial roles in embryogenesis. Here, we find that Cyp26a1, which encodes a key enzyme for catabolic inactivation of RA required for tight control of local RA concentrations, is significantly downregulated in embryos of diabetic mice. Embryonic tissues expressing Cyp26a1 show reduced efficiency of RA clearance. Embryos exposed to diabetes are thus sensitized to RA and more vulnerable to the deleterious effects of increased RA signaling. Susceptibility to RA teratogenesis is further potentiated in embryos with a preexisting genetic defect of RA metabolism. Increasing RA clearance efficiency using a preconditioning approach can counteract the increased susceptibility to RA teratogenesis in embryos of diabetic mice. Our findings provide new insight into gene-environment interactions that influence individual risk in the manifestation of diabetes-related birth defects and shed light on environmental risk factors and genetic variants for a stratified medicine approach to screening women with diabetes who are of childbearing age and assessing the risk of birth defects during pregnancy.
Collapse
Affiliation(s)
- Leo M Y Lee
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
- Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong
| | - Maran B W Leung
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Rachel C Y Kwok
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Yun Chung Leung
- Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University, Hong Kong
| | - Chi Chiu Wang
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
- Department of Obstetrics and Gynaecology, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
- Li Ka Shing Institute of Health Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| | - Peter J McCaffery
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, U.K
| | - Andrew J Copp
- Newlife Birth Defects Research Centre, Institute of Child Health, University College London, London, U.K
| | - Alisa S W Shum
- School of Biomedical Sciences, Faculty of Medicine, The Chinese University of Hong Kong, Hong Kong
| |
Collapse
|
22
|
Posterior tail development in the salamander Eurycea cirrigera: exploring cellular dynamics across life stages. Dev Genes Evol 2017; 227:85-99. [PMID: 28101674 DOI: 10.1007/s00427-016-0573-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2016] [Accepted: 12/22/2016] [Indexed: 10/20/2022]
Abstract
During embryogenesis, the body axis elongates and specializes. In vertebrate groups such as salamanders and lizards, elongation of the posterior body axis (tail) continues throughout life. This phenomenon of post-embryonic tail elongation via addition of vertebrae has remained largely unexplored, and little is known about the underlying developmental mechanisms that promote vertebral addition. Our research investigated tail elongation across life stages in a non-model salamander species, Eurycea cirrigera (Plethodontidae). Post-embryonic addition of segments suggests that the tail tip retains some aspects of embryonic cell/tissue organization and gene expression throughout the life cycle. We describe cell and tissue differentiation and segmentation of the posterior tail using serial histology and expression of the axial tissue markers, MF-20 and Pax6. Embryonic expression patterns of HoxA13 and C13 are shown with in situ hybridization. Tissue sections reveal that the posterior spinal cord forms via cavitation and precedes development of the underlying cartilaginous rod after embryogenesis. Post-embryonic tail elongation occurs in the absence of somites and mesenchymal cells lateral to the midline express MF-20. Pax6 expression was observed only in the spinal cord and some mesenchymal cells of adult Eurycea tails. Distinct temporal and spatial patterns of posterior Hox13 gene expression were observed throughout embryogenesis. Overall, important insights to cell organization, differentiation, and posterior Hox gene expression may be gained from this work. We suggest that further work on gene expression in the elongating adult tail could shed light on mechanisms that link continual axial elongation with regeneration.
Collapse
|
23
|
Neijts R, Amin S, van Rooijen C, Deschamps J. Cdx is crucial for the timing mechanism driving colinear Hox activation and defines a trunk segment in the Hox cluster topology. Dev Biol 2016; 422:146-154. [PMID: 28041967 DOI: 10.1016/j.ydbio.2016.12.024] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 12/09/2016] [Accepted: 12/27/2016] [Indexed: 11/28/2022]
Abstract
Cdx and Hox transcription factors are important regulators of axial patterning and are required for tissue generation along the vertebrate body axis. Cdx genes have been demonstrated to act upstream of Hox genes in midgestation embryos. Here, we investigate the role of Cdx transcription factors in the gradual colinear activation of the Hox clusters. We found that Hox temporally colinear expression is severely affected in epiblast stem cells derived from Cdx null embryos. We demonstrate that after initiation of 3' Hox gene transcription, Cdx activity is crucial for H3K27ac deposition and for accessibility of cis-regulatory elements around the central - or 'trunk' - Hox genes. We thereby identify a Cdx-responsive segment of HoxA, immediately 5' to the recently defined regulatory domain orchestrating initial transcription of the first Hox gene. We propose that this partition of HoxA into a Wnt-driven 3' part and the newly found Cdx-dependent middle segment of the cluster, forms a structural fundament of Hox colinearity of expression. Subsequently to initial Wnt-induced activation of 3' Hox genes, Cdx transcription factors would act as crucial effectors for activating central Hox genes, until the last gene of the cluster arrests the process.
Collapse
Affiliation(s)
- Roel Neijts
- Hubrecht Institute, Developmental Biology and Stem Cell Research, Uppsalalaan 8, 3584 CT Utrecht, and UMC Utrecht, the Netherlands
| | - Shilu Amin
- Hubrecht Institute, Developmental Biology and Stem Cell Research, Uppsalalaan 8, 3584 CT Utrecht, and UMC Utrecht, the Netherlands
| | - Carina van Rooijen
- Hubrecht Institute, Developmental Biology and Stem Cell Research, Uppsalalaan 8, 3584 CT Utrecht, and UMC Utrecht, the Netherlands
| | - Jacqueline Deschamps
- Hubrecht Institute, Developmental Biology and Stem Cell Research, Uppsalalaan 8, 3584 CT Utrecht, and UMC Utrecht, the Netherlands.
| |
Collapse
|
24
|
Molina A, Pituello F. Playing with the cell cycle to build the spinal cord. Dev Biol 2016; 432:14-23. [PMID: 28034699 DOI: 10.1016/j.ydbio.2016.12.022] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 12/14/2016] [Accepted: 12/20/2016] [Indexed: 12/31/2022]
Abstract
A fundamental issue in nervous system development and homeostasis is to understand the mechanisms governing the balance between the maintenance of proliferating progenitors versus their differentiation into post-mitotic neurons. Accumulating data suggest that the cell cycle and core regulators of the cell cycle machinery play a major role in regulating this fine balance. Here, we focus on the interplay between the cell cycle and cellular and molecular events governing spinal cord development. We describe the existing links between the cell cycle and interkinetic nuclear migration (INM). We show how the different morphogens patterning the neural tube also regulate the cell cycle machinery to coordinate proliferation and patterning. We give examples of how cell cycle core regulators regulate transcriptionally, or post-transcriptionally, genes involved in controlling the maintenance versus the differentiation of neural progenitors. Finally, we describe the changes in cell cycle kinetics occurring during neural tube patterning and at the time of neuronal differentiation, and we discuss future research directions to better understand the role of the cell cycle in cell fate decisions.
Collapse
Affiliation(s)
- Angie Molina
- Centre de Biologie du Développement (CBD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, France.
| | - Fabienne Pituello
- Centre de Biologie du Développement (CBD), Centre de Biologie Intégrative (CBI), Université de Toulouse, CNRS, UPS, France.
| |
Collapse
|
25
|
Cdx and T Brachyury Co-activate Growth Signaling in the Embryonic Axial Progenitor Niche. Cell Rep 2016; 17:3165-3177. [DOI: 10.1016/j.celrep.2016.11.069] [Citation(s) in RCA: 80] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Revised: 10/26/2016] [Accepted: 11/18/2016] [Indexed: 12/30/2022] Open
|
26
|
Anderson MJ, Schimmang T, Lewandoski M. An FGF3-BMP Signaling Axis Regulates Caudal Neural Tube Closure, Neural Crest Specification and Anterior-Posterior Axis Extension. PLoS Genet 2016; 12:e1006018. [PMID: 27144312 PMCID: PMC4856314 DOI: 10.1371/journal.pgen.1006018] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 04/08/2016] [Indexed: 01/08/2023] Open
Abstract
During vertebrate axis extension, adjacent tissue layers undergo profound morphological changes: within the neuroepithelium, neural tube closure and neural crest formation are occurring, while within the paraxial mesoderm somites are segmenting from the presomitic mesoderm (PSM). Little is known about the signals between these tissues that regulate their coordinated morphogenesis. Here, we analyze the posterior axis truncation of mouse Fgf3 null homozygotes and demonstrate that the earliest role of PSM-derived FGF3 is to regulate BMP signals in the adjacent neuroepithelium. FGF3 loss causes elevated BMP signals leading to increased neuroepithelium proliferation, delay in neural tube closure and premature neural crest specification. We demonstrate that elevated BMP4 depletes PSM progenitors in vitro, phenocopying the Fgf3 mutant, suggesting that excessive BMP signals cause the Fgf3 axis defect. To test this in vivo we increased BMP signaling in Fgf3 mutants by removing one copy of Noggin, which encodes a BMP antagonist. In such mutants, all parameters of the Fgf3 phenotype were exacerbated: neural tube closure delay, premature neural crest specification, and premature axis termination. Conversely, genetically decreasing BMP signaling in Fgf3 mutants, via loss of BMP receptor activity, alleviates morphological defects. Aberrant apoptosis is observed in the Fgf3 mutant tailbud. However, we demonstrate that cell death does not cause the Fgf3 phenotype: blocking apoptosis via deletion of pro-apoptotic genes surprisingly increases all Fgf3 defects including causing spina bifida. We demonstrate that this counterintuitive consequence of blocking apoptosis is caused by the increased survival of BMP-producing cells in the neuroepithelium. Thus, we show that FGF3 in the caudal vertebrate embryo regulates BMP signaling in the neuroepithelium, which in turn regulates neural tube closure, neural crest specification and axis termination. Uncovering this FGF3-BMP signaling axis is a major advance toward understanding how these tissue layers interact during axis extension with important implications in human disease. During embryological development, the vertebrate embryo undergoes profound growth in a head-to-tail direction. During this process, formation of different structures within adjacent tissue layers must occur in a coordinated fashion. Insights into how these adjacent tissues molecularly communicate with each other is essential to understanding both basic embryology and the underlying causes of human birth defects. Mice lacking Fgf3, which encodes a secreted signaling factor, have long been known to have premature axis termination, but the underlying mechanism has not been studied until now. Through a series of complex genetic experiments, we show that FGF3 is an essential factor for coordination of neural tube development and axis extension. FGF3 is secreted from the mesodermal layer, which is the major driver of extending the axis, and negatively regulates expression of another class of secreted signaling molecules in the neuroepithelium, BMPs. In the absence of FGF3, excessive BMP signals cause a delay in neural tube closure, premature specification of neural crest cells and negatively affect the mesoderm, causing a premature termination of the embryological axis. Our work suggests that FGF3 may be a player in the complex etiology of the human birth defect, spina bifida, the failure of posterior neural tube closure.
Collapse
Affiliation(s)
- Matthew J. Anderson
- Genetics of Vertebrate Development Section, Cancer and Developmental Biology Lab, National Cancer Institute, National Institutes of Health, Frederick, Maryland, United States of America
| | - Thomas Schimmang
- Instituto de Biología y Genética Molecular, Universidad de Valladolid y Consejo Superior de Investigaciones Científicas, Valladolid, Spain
| | - Mark Lewandoski
- Genetics of Vertebrate Development Section, Cancer and Developmental Biology Lab, National Cancer Institute, National Institutes of Health, Frederick, Maryland, United States of America
- * E-mail:
| |
Collapse
|
27
|
Steventon B, Duarte F, Lagadec R, Mazan S, Nicolas JF, Hirsinger E. Species-specific contribution of volumetric growth and tissue convergence to posterior body elongation in vertebrates. Development 2016; 143:1732-41. [PMID: 26989170 DOI: 10.1242/dev.126375] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2015] [Accepted: 03/09/2016] [Indexed: 01/04/2023]
Abstract
Posterior body elongation is a widespread mechanism propelling the generation of the metazoan body plan. The posterior growth model predicts that a posterior growth zone generates sufficient tissue volume to elongate the posterior body. However, there are energy supply-related differences between vertebrates in the degree to which growth occurs concomitantly with embryogenesis. By applying a multi-scalar morphometric analysis in zebrafish embryos, we show that posterior body elongation is generated by an influx of cells from lateral regions, by convergence-extension of cells as they exit the tailbud, and finally by a late volumetric growth in the spinal cord and notochord. Importantly, the unsegmented region does not generate additional tissue volume. Fibroblast growth factor inhibition blocks tissue convergence rather than volumetric growth, showing that a conserved molecular mechanism can control convergent morphogenesis through different cell behaviours. Finally, via a comparative morphometric analysis in lamprey, dogfish, zebrafish and mouse, we propose that elongation via posterior volumetric growth is linked to increased energy supply and is associated with an overall increase in volumetric growth and elongation.
Collapse
Affiliation(s)
- Ben Steventon
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 25 rue du Docteur Roux, Paris cedex 15 75724, France
| | - Fernando Duarte
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 25 rue du Docteur Roux, Paris cedex 15 75724, France
| | - Ronan Lagadec
- Development and Evolution of Vertebrates, CNRS-UPMC-UMR 7150, Station Biologique, Roscoff 29680, France CNRS, Sorbonne Universités, UPMC Univ Paris 06, UMR7232, Observatoire Océanologique, Banyuls 66650, France
| | - Sylvie Mazan
- Development and Evolution of Vertebrates, CNRS-UPMC-UMR 7150, Station Biologique, Roscoff 29680, France CNRS, Sorbonne Universités, UPMC Univ Paris 06, UMR7232, Observatoire Océanologique, Banyuls 66650, France
| | - Jean-François Nicolas
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 25 rue du Docteur Roux, Paris cedex 15 75724, France
| | - Estelle Hirsinger
- Department of Developmental and Stem Cell Biology, Institut Pasteur, 25 rue du Docteur Roux, Paris cedex 15 75724, France
| |
Collapse
|
28
|
Henrique D, Abranches E, Verrier L, Storey KG. Neuromesodermal progenitors and the making of the spinal cord. Development 2015; 142:2864-75. [PMID: 26329597 PMCID: PMC4958456 DOI: 10.1242/dev.119768] [Citation(s) in RCA: 212] [Impact Index Per Article: 23.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Neuromesodermal progenitors (NMps) contribute to both the elongating spinal cord and the adjacent paraxial mesoderm. It has been assumed that these cells arise as a result of patterning of the anterior neural plate. However, as the molecular mechanisms that specify NMps in vivo are uncovered, and as protocols for generating these bipotent cells from mouse and human pluripotent stem cells in vitro are established, the emerging data suggest that this view needs to be revised. Here, we review the characteristics, regulation, in vitro derivation and in vivo induction of NMps. We propose that these cells arise within primitive streak-associated epiblast via a mechanism that is separable from that which establishes neural fate in the anterior epiblast. We thus argue for the existence of two distinct routes for making central nervous system progenitors.
Collapse
Affiliation(s)
- Domingos Henrique
- Instituto de Medicina Molecular and Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina da Universidade de Lisboa, Avenida Prof. Egas Moniz, Lisboa 1649-028, Portugal
| | - Elsa Abranches
- Instituto de Medicina Molecular and Instituto de Histologia e Biologia do Desenvolvimento, Faculdade de Medicina da Universidade de Lisboa, Avenida Prof. Egas Moniz, Lisboa 1649-028, Portugal
| | - Laure Verrier
- Division of Cell & Developmental Biology, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| | - Kate G Storey
- Division of Cell & Developmental Biology, College of Life Sciences, University of Dundee, Dow Street, Dundee DD1 5EH, UK
| |
Collapse
|
29
|
Independent regulation of vertebral number and vertebral identity by microRNA-196 paralogs. Proc Natl Acad Sci U S A 2015; 112:E4884-93. [PMID: 26283362 DOI: 10.1073/pnas.1512655112] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
The Hox genes play a central role in patterning the embryonic anterior-to-posterior axis. An important function of Hox activity in vertebrates is the specification of different vertebral morphologies, with an additional role in axis elongation emerging. The miR-196 family of microRNAs (miRNAs) are predicted to extensively target Hox 3' UTRs, although the full extent to which miR-196 regulates Hox expression dynamics and influences mammalian development remains to be elucidated. Here we used an extensive allelic series of mouse knockouts to show that the miR-196 family of miRNAs is essential both for properly patterning vertebral identity at different axial levels and for modulating the total number of vertebrae. All three miR-196 paralogs, 196a1, 196a2, and 196b, act redundantly to pattern the midthoracic region, whereas 196a2 and 196b have an additive role in controlling the number of rib-bearing vertebra and positioning of the sacrum. Independent of this, 196a1, 196a2, and 196b act redundantly to constrain total vertebral number. Loss of miR-196 leads to a collective up-regulation of numerous trunk Hox target genes with a concomitant delay in activation of caudal Hox genes, which are proposed to signal the end of axis extension. Additionally, we identified altered molecular signatures associated with the Wnt, Fgf, and Notch/segmentation pathways and demonstrate that miR-196 has the potential to regulate Wnt activity by multiple mechanisms. By feeding into, and thereby integrating, multiple genetic networks controlling vertebral number and identity, miR-196 is a critical player defining axial formulae.
Collapse
|
30
|
Gouti M, Metzis V, Briscoe J. The route to spinal cord cell types: a tale of signals and switches. Trends Genet 2015; 31:282-9. [PMID: 25823696 DOI: 10.1016/j.tig.2015.03.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 02/28/2015] [Accepted: 03/02/2015] [Indexed: 01/20/2023]
Abstract
Understanding the mechanisms that control induction and elaboration of the vertebrate central nervous system (CNS) requires an analysis of the extrinsic signals and downstream transcriptional networks that assign cell fates in the correct space and time. We focus on the generation and patterning of the spinal cord. We summarize evidence that the origin of the spinal cord is distinct from the anterior regions of the CNS. We discuss how this affects the gene regulatory networks and cell state transitions that specify spinal cord cell subtypes, and we highlight how the timing of extracellular signals and dynamic control of transcriptional networks contribute to the correct spatiotemporal generation of different neural cell types.
Collapse
Affiliation(s)
- Mina Gouti
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - Vicki Metzis
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London, NW7 1AA, UK
| | - James Briscoe
- The Francis Crick Institute, Mill Hill Laboratory, The Ridgeway, Mill Hill, London, NW7 1AA, UK.
| |
Collapse
|
31
|
Cunningham TJ, Duester G. Mechanisms of retinoic acid signalling and its roles in organ and limb development. Nat Rev Mol Cell Biol 2015; 16:110-23. [PMID: 25560970 PMCID: PMC4636111 DOI: 10.1038/nrm3932] [Citation(s) in RCA: 387] [Impact Index Per Article: 43.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Retinoic acid (RA) signalling has a central role during vertebrate development. RA synthesized in specific locations regulates transcription by interacting with nuclear RA receptors (RARs) bound to RA response elements (RAREs) near target genes. RA was first implicated in signalling on the basis of its teratogenic effects on limb development. Genetic studies later revealed that endogenous RA promotes forelimb initiation by repressing fibroblast growth factor 8 (Fgf8). Insights into RA function in the limb serve as a paradigm for understanding how RA regulates other developmental processes. In vivo studies have identified RAREs that control repression of Fgf8 during body axis extension or activation of homeobox (Hox) genes and other key regulators during neuronal differentiation and organogenesis.
Collapse
Affiliation(s)
- Thomas J Cunningham
- Development, Aging, and Regeneration Program, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, California 92037, USA
| | - Gregg Duester
- Development, Aging, and Regeneration Program, Sanford-Burnham Medical Research Institute, 10901 N. Torrey Pines Road, La Jolla, California 92037, USA
| |
Collapse
|
32
|
Tonk ECM, Pennings JLA, Piersma AH. An adverse outcome pathway framework for neural tube and axial defects mediated by modulation of retinoic acid homeostasis. Reprod Toxicol 2014; 55:104-13. [PMID: 25461899 DOI: 10.1016/j.reprotox.2014.10.008] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/12/2014] [Accepted: 10/07/2014] [Indexed: 11/29/2022]
Abstract
Developmental toxicity can be caused through a multitude of mechanisms and can therefore not be captured through a single simple mechanistic paradigm. However, it may be possible to define a selected group of overarching mechanisms that might allow detection of the vast majority of developmental toxicants. Against this background, we have explored the usefulness of retinoic acid mediated regulation of neural tube and axial patterning as a general mechanism that, when perturbed, may result in manifestations of developmental toxicity that may cover a large part of malformations known to occur in experimental animals and in man. Through a literature survey, we have identified key genes in the regulation of retinoic acid homeostasis, as well as marker genes of neural tube and axial patterning, that may be used to detect developmental toxicants in in vitro systems. A retinoic acid-neural tube/axial patterning adverse outcome pathway (RA-NTA AOP) framework was designed. The framework was tested against existing data of flusilazole exposure in the rat whole embryo culture, the zebrafish embryotoxicity test, and the embryonic stem cell test. Flusilazole is known to interact with retinoic acid homeostasis, and induced common and unique NTA marker gene changes in the three test systems. Flusilazole-induced changes were similar in directionality to gene expression responses after retinoic acid exposure. It is suggested that the RA-NTA framework may provide a general tool to define mechanistic pathways and biomarkers of developmental toxicity that may be used in alternative in vitro assays for the detection of embryotoxic compounds.
Collapse
Affiliation(s)
- Elisa C M Tonk
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands
| | - Jeroen L A Pennings
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands
| | - Aldert H Piersma
- Center for Health Protection, National Institute for Public Health and The Environment (RIVM), P.O. Box 1, 3720BA Bilthoven, The Netherlands; Institute for Risk Assessment Sciences, Utrecht University, Utrecht, The Netherlands.
| |
Collapse
|