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Niva CC, Lee JM, Myohara M. Glutamine synthetase gene expression during the regeneration of the annelid Enchytraeus japonensis. Dev Genes Evol 2008; 218:39-46. [PMID: 18183418 PMCID: PMC2265772 DOI: 10.1007/s00427-007-0198-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Accepted: 11/27/2007] [Indexed: 11/29/2022]
Abstract
Enchytraeus japonensis is a highly regenerative oligochaete annelid that can regenerate a complete individual from a small body fragment in 4–5 days. In our previous study, we performed complementary deoxyribonucleic acid subtraction cloning to isolate genes that are upregulated during E. japonensis regeneration and identified glutamine synthetase (gs) as one of the most abundantly expressed genes during this process. In the present study, we show that the full-length sequence of E. japonensis glutamine synthetase (EjGS), which is the first reported annelid glutamine synthetase, is highly similar to other known class II glutamine synthetases. EjGS shows a 61–71% overall amino acid sequence identity with its counterparts in various other animal species, including Drosophila and mouse. We performed detailed expression analysis by in situ hybridization and reveal that strong gs expression occurs in the blastemal regions of regenerating E. japonensis soon after amputation. gs expression was detectable at the cell layer covering the wound and was found to persist in the epidermal cells during the formation and elongation of the blastema. Furthermore, in the elongated blastema, gs expression was detectable also in the presumptive regions of the brain, ventral nerve cord, and stomodeum. In the fully formed intact head, gs expression was also evident in the prostomium, brain, the anterior end of the ventral nerve cord, the epithelium of buccal and pharyngeal cavities, the pharyngeal pad, and in the esophageal appendages. In intact E. japonensis tails, gs expression was found in the growth zone in actively growing worms but not in full-grown individuals. In the nonblastemal regions of regenerating fragments and in intact worms, gs expression was also detected in the nephridia, chloragocytes, gut epithelium, epidermis, spermatids, and oocytes. These results suggest that EjGS may play roles in regeneration, nerve function, cell proliferation, nitrogenous waste excretion, macromolecule synthesis, and gametogenesis.
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Affiliation(s)
- Cintia Carla Niva
- Invertebrate Gene Function Research Unit, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
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Myohara M, Niva CC, Lee JM. Molecular approach to annelid regeneration: cDNA subtraction cloning reveals various novel genes that are upregulated during the large-scale regeneration of the oligochaete, Enchytraeus japonensis. Dev Dyn 2006; 235:2051-70. [PMID: 16724321 DOI: 10.1002/dvdy.20849] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
To identify genes specifically activated during annelid regeneration, suppression subtractive hybridization was performed with cDNAs from regenerating and intact Enchytraeus japonensis, a terrestrial oligochaete that can regenerate a complete organism from small body fragments within 4-5 days. Filter array screening subsequently revealed that about 38% of the forward-subtracted cDNA clones contained genes that were upregulated during regeneration. Two hundred seventy-nine of these clones were sequenced and found to contain 165 different sequences (79 known and 86 unknown). Nine clones were fully sequenced and four of these sequences were matched to known genes for glutamine synthetase, glucosidase 1, retinal protein 4, and phosphoribosylaminoimidazole carboxylase, respectively. The remaining five clones encoded an unknown open-reading frame. The expression levels of these genes were highest during blastema formation. Our present results, therefore, demonstrate the great potential of annelids as a new experimental subject for the exploration of unknown genes that play critical roles in animal regeneration.
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Affiliation(s)
- Maroko Myohara
- Developmental Biology Department, National Institute of Agrobiological Sciences, Tsukuba, Ibaraki, Japan.
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Shibata M, Itoh M, Ohmori SY, Shinga J, Taira M. Systematic screening and expression analysis of the head organizer genes in Xenopus embryos. Dev Biol 2001; 239:241-56. [PMID: 11784032 DOI: 10.1006/dbio.2001.0428] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
We describe here a systematic screen of an anterior endomesoderm (AEM) cDNA library to isolate novel genes which are expressed in the head organizer region. After removing clones which hybridized to labeled cDNA probes synthesized with total RNA from a trunk region of tailbud embryos, the 5' ends of 1039 randomly picked cDNA clones were sequenced to make expressed sequence tags (ESTs), which formed 754 tentative unique clusters. Those clusters were compared against public databases and classified according to similarities found to other genes and gene products. Of them, 151 clusters were identified as known Xenopus genes, including eight organizer-specific ones (5.3%). Gene expression pattern screening was performed for 198 unique clones, which were selected because they either have no known function or are predicted to be developmental regulators in other species. The screen revealed nine possible organizer-specific clones (4.5%), four of which appeared to be expressed in the head organizer region. Detailed expression analysis from gastrula to neurula stages showed that these four genes named crescent, P7E4 (homologous to human hypothetical genes), P8F7 (an unclassified gene), and P17F11 (homologous to human and Arabidopsis hypothetical genes) demarcate spatiotemporally distinct subregions of the AEM corresponding to the head organizer region. These results indicate that our screening strategy is effective in isolating novel region-specific genes.
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Affiliation(s)
- M Shibata
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Tamai K, Yokota C, Ariizumi T, Asashima M. Cytochalasin B inhibits morphogenetic movement and muscle differentiation of activin-treated ectoderm in Xenopus. Dev Growth Differ 1999; 41:41-9. [PMID: 10445501 DOI: 10.1046/j.1440-169x.1999.00404.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Xenopus ectodermal explants (animal caps) begin to elongate after treatment with the mesoderm inducing factor activin A. This phenomenon mimics the convergent extension of dorsal mesoderm during gastrulation. To analyze the relationship between elongation movement and muscle differentiation, animal caps were treated with colchicine, taxol, cytochalasin B and hydroxyurea (HUA)/aphidicolin following activin treatment. Cytochalasin B disrupted the organization of actin filaments and inhibited the elongation of the activin-treated explants. Muscle differentiation was also inhibited in these explants at the histologic and molecular levels. Colchicine and taxol, which are known to affect microtubule organization, had little effect on elongation of the activin-treated exp ants. Co-treatment with HUA and aphidicolin caused serious damage on the explants and they did not undergo elongation. These results suggest that actin filaments play an important role in the elongation movement that leads to muscle differentiation of activin-treated explants.
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Affiliation(s)
- K Tamai
- Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo, Japan
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Moriya N, Yokota C, Ariizumi T, Asashima M. In vitroControl of Embryonic Axis Formation by Activin A, Concanavalin A, and Retinoic Acid in Xenopus laevis. Zoolog Sci 1998. [DOI: 10.2108/zsj.15.879] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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Lie-Venema H, Hakvoort TB, van Hemert FJ, Moorman AF, Lamers WH. Regulation of the spatiotemporal pattern of expression of the glutamine synthetase gene. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1998; 61:243-308. [PMID: 9752723 DOI: 10.1016/s0079-6603(08)60829-6] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Glutamine synthetase, the enzyme that catalyzes the ATP-dependent conversion of glutamate and ammonia into glutamine, is expressed in a tissue-specific and developmentally controlled manner. The first part of this review focuses on its spatiotemporal pattern of expression, the factors that regulate its levels under (patho)physiological conditions, and its role in glutamine, glutamate, and ammonia metabolism in mammals. Glutamine synthetase protein stability is more than 10-fold reduced by its product glutamine and by covalent modifications. During late fetal development, translational efficiency increases more than 10-fold. Glutamine synthetase mRNA stability is negatively affected by cAMP, whereas glucocorticoids, growth hormone, insulin (all positive), and cAMP (negative) regulate its rate of transcription. The signal transduction pathways by which these factors may regulate the expression of glutamine synthetase are briefly discussed. The second part of the review focuses on the evolution, structure, and transcriptional regulation of the glutamine synthetase gene in rat and chicken. Two enhancers (at -6.5 and -2.5 kb) were identified in the upstream region and two enhancers (between +156 and +857 bp) in the first intron of the rat glutamine synthetase gene. In addition, sequence analysis suggests a regulatory role for regions in the 3' untranslated region of the gene. The immediate-upstream region of the chicken glutamine synthetase gene is responsible for its cell-specific expression, whereas the glucocorticoid-induced developmental appearance in the neural retina is governed by its far-upstream region.
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Affiliation(s)
- H Lie-Venema
- Department of Anatomy and Embryology, University of Amsterdam, The Netherlands
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Takahashi S, Uochi T, Kawakami Y, Nohno T, Yokota C, Kinoshita K, Asashima M. Cloning and expression pattern of Xenopus prx-1 (Xprx-1) during embryonic development. Dev Growth Differ 1998; 40:97-104. [PMID: 9563915 DOI: 10.1046/j.1440-169x.1998.t01-6-00011.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Homeobox genes are expressed both temporally and spatially during vertebrate development, and regulate the tissue-specific expression of other genes. A Xenopus paired-related homeobox- 1 (Xprx-1) cDNA was cloned. Xprx-1 had a paired-related homeodomain, but did not contain a paired-box. The sequence of Xprx-1 had a high level of homology with K-2(mouse) and Prx-1 (chicken), thus Xprx-1 is assumed to be the Xenopus homolog of these genes. Xprx-1 transcripts were maternally restricted, in Xenopus embryos, and a decrease in the late blastula stage was followed by an increase in zygotic transcripts after gastrulation. The transcripts were localized to the animal hemisphere of the late blastula and were concentrated in the branchial arches of the tail-bud stage embryo. In animal cap experiments, Activin A dose-dependently induced Xprx-1 gene expression. These results suggest that Xprx-1 plays a role in early Xenopus development similar to other species.
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Affiliation(s)
- S Takahashi
- Department of Life Science (Biology), Japan Science and Technology Corporation, The University of Tokyo, Meguro, Japan
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Hatada S, Kinoshita M, Takahashi S, Nishihara R, Sakumoto H, Fukui A, Noda M, Asashima M. An interferon regulatory factor-related gene (xIRF-6) is expressed in the posterior mesoderm during the early development of Xenopus laevis. Gene X 1997; 203:183-8. [PMID: 9426249 DOI: 10.1016/s0378-1119(97)00512-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Out of a Xenopus neurula cDNA library, we isolated a clone which encodes a 52.4-kDa protein highly similar to the mouse interferon regulatory factor, IRF-6, whose function is unknown. The mRNA of this gene, named xIRF-6, seems to be maternally transmitted, but its amount rapidly decreases after the tailbud stage. Whole-mount in situ hybridization showed that xIRF-6 mRNA is expressed in the presumptive somitic mesoderm in the late gastrula, and then confined to a segment of posterior somite during the neurula through the tailbud stage. The temporally and spatially limited expression of the xIRF-6 gene product may contribute to the transcriptional regulation of specific genes which are necessary for the development of the posterior somites.
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Affiliation(s)
- S Hatada
- Department of Biological Science, Graduate School of Science, University of Tokyo, Japan
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Hatada S, Kinoshita M, Sakumoto H, Nishihara R, Noda M, Asashima M. A novel gene encoding a ferredoxin reductase-like protein expressed in the neuroectoderm in Xenopus neurula. Gene X 1997; 194:297-9. [PMID: 9272874 DOI: 10.1016/s0378-1119(97)00208-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
In an attempt to elucidate the molecular mechanisms of early neural development in Xenopus laevis, we identified, using a differential display method, several genes that are induced after Concanavalin A treatment in the animal caps prepared from stage 9 blastula. One such gene was found to encode a possible type IIIa membrane protein of 66.2 kDa sharing similarities with several prokaryotic and eukaryotic redox enzymes, hence the putative product was named Nfrl, neurula-specific ferredoxin reductase-like protein. Northern blot analysis confirmed that the expression of the Nfrl gene is up-regulated around the neurula stage, and is much lower in embryos of earlier stages and in adult tissues. The temporally limited expression of this gene implies neurula- and early larva-specific redox reactions of certain substrates, the nature of which remains to be elucidated.
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Affiliation(s)
- S Hatada
- Institute of Biological Science, Graduate School of Science, University of Tokyo, Japan
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Takebayashi K, Takahashi S, Yokota C, Tsuda H, Nakanishi S, Asashima M, Kageyama R. Conversion of ectoderm into a neural fate by ATH-3, a vertebrate basic helix-loop-helix gene homologous to Drosophila proneural gene atonal. EMBO J 1997; 16:384-95. [PMID: 9029157 PMCID: PMC1169643 DOI: 10.1093/emboj/16.2.384] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
We have isolated a novel basic helix-loop-helix (bHLH) gene homologous to the Drosophila proneural gene atonal, termed ATH-3, from Xenopus and mouse. ATH-3 is expressed in the developing nervous system, with high levels of expression in the brain, retina and cranial ganglions. Injection of ATH-3 RNA into Xenopus embryos dramatically expands the neural tube and induces ectopic neural tissues in the epidermis but inhibits non-neural development. This ATH-3-induced neural hyperplasia does not require cell division, indicating that surrounding cells which are normally non-neural types adopt a neural fate. In a Xenopus animal cap assay, ATH-3 is able to convert ectodermal cells into neurons expressing anterior markers without inducing mesoderm. Interestingly, a single amino acid change from Ser to Asp in the basic region, which mimics phosphorylation of Ser, severely impairs the anterior marker-inducing ability without affecting general neurogenic activities. These results provide evidence that ATH-3 can directly convert non-neural or undetermined cells into a neural fate, and suggest that the Ser residue in the basic region may be critical for the regulation of ATH-3 activity by phosphorylation.
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Affiliation(s)
- K Takebayashi
- Department of Biological Sciences, Kyoto University Faculty of Medicine, Yoshida, Sakyo-ku, Japan
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