Sumario:
The International Journal of Developmental Biology
Euskal Herriko Unibertsitateko Argitalpen Zerbitzua / Servicio Editorial de la Universidad del País Vasco / University of the Basque Country Press
Volume 57 - Number 1 (2013) Editor-in-Chief: Juan Aréchaga
MORE INFORMATION [Abstract - FullText / FullText Open Access]
ISSN: 0214-6282 / ISSN-e: 1696-3547 www.intjdevbiol.com
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CONTENTS
Review
Signaling pathways during maintenance and definitive endoderm differentiation of embryonic stem cells
Lina Sui, Luc Bouwens and Josué K. Mfopou
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 1-12
Original Articles
In vivo imaging of Drosophila wing heart development during pupal stages
Markus Tögel, Günther Pass and Achim Paululat
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 13-24
The internal structure of embryonic gonads and testis development in Drosophila melanogaster requires scrib, lgl and dlg activity in the soma
Fani Papagiannouli
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 25-34
The NOBOX protein becomes undetectable in developmentally competent antral and ovulated oocytes
Martina Belli, Danilo Cimadomo, Valeria Merico, Carlo A. Redi, Silvia Garagna and Maurizio Zuccotti
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 35-39
Characterization of CXC-type chemokine molecules in early Xenopus laevis development
Toshiyasu Goto, Tatsuo Michiue, Yuzuru Ito and Makoto Asashima
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 41-47
The Wnt signaling mediator tcf1 is required for expression of foxd3 during Xenopus gastrulation
Sylvie Janssens, Olaf Van Den Broek, Ian R. Davenport, Robbert C. Akkers, Fei Liu, Gert Jan C. Veenstra, Stefan Hoppler, Kris Vleminckx and Olivier Destrée
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 49-54
Microtubule disassembly prevents palatal fusion and alters regulation of the E-cadherin/catenin complex
Yukiko Kitase and Charles F. Shuler
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 55-60
Technical Article
Successful whole embryo culture with commercially available reagents
Hannah C. Glanville-Jones, Ngai Woo and Ruth M. Arkell
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 61-67
Short Communication
Innate sexuality determines the mechanisms of telomere maintenance
Kenta Tasaka, Naoki Yokoyama, Hanae Nodono, Motonori Hoshi and Midori Matsumoto
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 69-72
Developmental Expression Patterns
Brachyury, Tbx2/3 and sall expression during embryogenesis of the indirectly developing polychaete Hydroides elegans
Cesar Arenas-Mena
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 73-83
Characterization and expression analysis of mcoln1.1 and mcoln1.2, the putative zebrafish co-orthologs of the gene responsible for human mucolipidosis type IV
Anna Benini, Andrea Bozzato, Silvia Mantovanelli, Laura Calvarini, Edoardo Giacopuzzi, Roberto Bresciani, Silvia Moleri, Daniela Zizioli, Monica Beltrame and Giuseppe Borsani
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 85-93
Expression of xSDF-1α, xCXCR4, and xCXCR7 during gastrulation in Xenopus laevis
Surabhi-Kirti Mishra, Tomoko Nagata, Kazuya Furusawa,Naoki Sasaki and Akimasa Fukui
EHU/UPV/UBC - The International Journal of Developmental Biology (2013) 57: 95-100
The International Journal of Developmental Biology
ISSN 1696-3547 (online) and 0214-6282 (print)
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CONTENTS
Review
EHU/UPV/UBC - The International Journal of Developmental Biology 57: 1-12 (2013)
doi: 10.1387/ijdb.120115ls / © UBC Press (www.a360grados.net)
Signaling pathways during maintenance and definitive endoderm differentiation of embryonic stem cells
Lina Sui, Luc Bouwens and Josué K. Mfopou
Cell Differentiation Unit, Diabetes Research Center, Vrije Universiteit Brussel, Brussels, Belgium
ABSTRACT: Embryonic stem cells (ESCs) have the potential to be used as unlimited resources for tissue replacement therapy, thereby compensating for organ donor shortage. To reach this goal, the molecular principles governing early differentiation events in the developing embryo need to be addressed, understood and properly implemented in vitro. Studies carried out in several vertebrate models have established that Nodal/Activin A, BMP, WNT and FGF signaling pathways regulate early embryo development and that these pathways are similarly used during germ layer formation by cultured ESCs. However, differences have also been identified in the way these pathways function or interact in mouse vs. human ESCs, making it sometimes difficult to extrapolate findings from one system to the other. In this review, we discuss and compare the role of the relevant signaling pathways and their crosstalk during undifferentiated growth and during the endoderm differentiation of mouse and human ESCs.
Keywords: human embryonic stem cell, mouse embryonic stem cells definitive endoderm, FGF, Nodal/Activin A
Original Articles ---------------------------------------------------------------------------
EHU/UPV/UBC - The International Journal of Developmental Biology 57: 13-24 (2013)
doi: 10.1387/ijdb.120115ls / © UBC Press (www.a360grados.net)
In vivo imaging of Drosophila wing heart development during pupal stages
Markus Tögel 1,2, Günther Pass 2 and Achim Paululat 1
1. Department of Biology, University of Osnabrück, Zoology/Developmental Biology, Osnabrück, Germany
2. Department of Evolutionary Biology, University of Vienna, Vienna, Austria
ABSTRACT: Wing hearts are small pumping organs that maintain the flow of hemolymph through the wing veins of insects. In Drosophila, these organs consist of parallel oriented muscle cells and a simple epithelium of connective tissue. Both tissues originate from eight embryonic wing heart progenitors (WHPs), which remain dormant until late larval stages. Most of the differentiation and maturation takes place during the pupal stage following head eversion. In this study, we have used the tissue specific expression of Gal4 enhancer lines, in combination with the live cell markers GFP and DsRed to investigate pupal wing heart development in conjunction with the surrounding tissues. We found that WHPs interact with the tracheal system and specific expression domains of the adult epidermis. Additionally, wing heart development occurs simultaneously with the remodeling of the dorso-lateral epidermis into the scutellum and the scutellar arms. Myogenesis in wing hearts comprises known processes such as founder cell specification, but also new features like removal of growing myotubes, and nuclei movement. Wing heart epithelium development is accomplished by the mesenchymal-epithelial transition of WHPs and occurs slightly delayed to muscle development. The epithelium represents a novel mesodermally derived secondary epithelium. Moreover, we have identified a nerve that runs along the epithelium and innervates the wing heart muscle cells.
Keywords: adult myogenesis, nuclear migration, pannier, engrailed, circulatory organ, mesenchymal-epithelial transition
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 25-34 (2013)
doi: 10.1387/ijdb.120087fp / © UBC Press (www.a360grados.net)
The internal structure of embryonic gonads and testis development in Drosophila melanogaster requires scrib, lgl and dlg activity in the soma
Fani Papagiannouli
Centre for Organismal Studies (COS) Heidelberg, University of Heidelberg, Germany
ABSTRACT: Interest in the mechanism leading to the formation of the germline and its differentiation during Drosophila development, initiated even as soon as the first ever cloned tumour suppressor gene in Drosophila, the lethal (2) giant larvae (lgl), had been identified. Further work has shown that the lgl, as well as discs large-1 (dlg) and scribble (scrib) tumor suppressor genes code for scaffolding proteins associated with either the cytoskeletal matrix or the septate junctions that act in common pathways in various tissues. This study analysed the role of Dlg, Scrib and Lgl in the embryonic gonads and testis of Drosophila melanogaster. Loss of scrib, dlg and lgl had no effect on gonad formation, but Dlg and Scrib in the gonadal mesoderm acted critically in the somatic wrapping of the pole cells and the internal structure of the Drosophila embryonic gonads. Dlg also affected the incorporation of the male-specific Sox100B positive mesodermal cells into the male embryonic gonads, yet Sox100B expression in dlg testis remained unaffected. Analysis at later stages revealed that scrib and lgl expression in the somatic lineage of the Drosophila testis, similar to what was previously shown for dlg, was indispensable for testis development and homeostasis, as depletion of these genes resulted in extensive testes defects. The data presented here emphasize the somatic requirement of Scrib, Dlg and Lgl in embryonic gonads, as well as in the Drosophila testis that underlines the importance of the somatic lineage in the establishment and maintenance of testis formation throughout successive developmental stages.
Keywords: dlg, lgl, scrib, gonads, Drosophila testis
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 35-39 (2013)
doi: 10.1387/ijdb.120125mz / © UBC Press (www.a360grados.net)
The NOBOX protein becomes undetectable in developmentally competent antral and ovulated oocytes
Martina Belli 1, Danilo Cimadomo 1, Valeria Merico 1, Carlo A. Redi 1, Silvia Garagna 1,2,3, and Maurizio Zuccotti 4.
1. Laboratorio di Biologia dello Sviluppo, Dipartimento di Biologia e Biotecnologie 'Lazzaro Spallanzani', Universita` degli Studi di Pavia, Pavia
2. Centro di Ingegneria Tissutale, Universita’ degli Studi di Pavia, Pavia
3. Centro di Eccellenza in Biologia Applicata, Universita’ degli Studi di Pavia, Pavia
4. Unitŕ di Anatomia, Istologia ed Embriologia, Dipartimento di Scienze Biomediche, Biotecnologiche e Traslazionali (S.Bi.Bi.T.), Universita' degli Studi di Parma, Italy
ABSTRACT: The oocyte-specific NOBOX protein is an important player during oocyte growth. Its absence in Nobox-/- mice arrests the transition from primordial to growing follicles and down-regulates the expression of a number of genes, including Oct4, a transcription factor crucial in the acquisition of oocyte developmental competence. Despite its role during folliculogenesis, a clear description of the expression of NOBOX throughout oocyte growth is lacking. Here, we have analysed the pattern of expression of both the Nobox gene (qRT-PCR) and its protein (immunofluorescence) during folliculogenesis, classifying the oocytes based on their size (six classes: 10-30, 31-40, 41-50, 51-60, 61-70, 71-80 µm) and chromatin organisation (NSN, Non Surrounded Nucleolus or SN, Surrounded Nucleolus). Significant differences were observed in Nobox transcription in the group of 41-50 µm (NSN > SN), 71-80 µm (NSN > SN) and in developmentally incompetent metaphase II-derived NSN (MIINSN) or competent metaphase II-derived SN (MIISN) oocytes (MIINSN > MIISN). The NOBOX protein is expressed throughout oocyte growth in the nucleus of ovarian NSN and in MIINSN oocytes; in contrast, beginning with SN oocytes of 61-70 µm, it becomes almost undetectable. Our data, while being in line with the hypothesis of a regulative role of NOBOX on Oct4 gene expression at the primordial/primary stage, when both transcription factors are coincidentally expressed, also indicate that this role might not be maintained in the subsequent growing stages. Furthermore, the sharp difference of NOBOX expression in developmentally incompetent or competent oocytes makes this protein a putative marker of their quality.
Keywords: NOBOX, oocyte growth, oocyte developmental competence, folliculogenesis
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 41-47 (2013)
doi: 10.1387/ijdb.120223ma / © UBC Press (www.a360grados.net)
Characterization of CXC-type chemokine molecules in early Xenopus laevis development
Toshiyasu Goto 1, Tatsuo Michiue 2, Yuzuru Ito 3 and Makoto Asashima 2,3
1. Department of Molecular Cell Biology, Medical Research Institute and School of Biomedical Science, Tokyo Medical and Dental University, Tokyo
2. Department of Life Sciences (Biology), Graduate School of Arts and Sciences, The University of Tokyo, Tokyo
3. Research Center for Stem Cell Engineering, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan
ABSTRACT: Chemokine molecules play important roles in the immune system. However, several chemokine molecules are expressed during early development before the immune system is established. Using reverse transcription–polymerase chain reaction (RT-PCR) and overexpression of chemokine molecules, we identified and characterized Xenopus laevis CXC-type chemokine ligands (XCXCL13L1, XCXCL13L2, XCXCLa, XCXCLb, XCXCLd, and XCXCLe) and receptors (XCXCR1/2, XCXCR3, XCXCR5, XCXCR6, and XCXCRa) during early development. The CXC-type ligands have low identity with genes for human CXC ligands (CXCL). With the exception of XCXCRa, the CXC receptors (CXCR) identified in the present study had high (40%–65%) identity with human CXCR genes. Although the expression patterns for the CXCL and CXCR genes differed, transcript levels for all genes were very low during early embryogenesis. Overexpression of XCXCL13L1, XCXCL13L2, XCXCLa, XCXCR3, XCXCR6, and XCXCRa interfered with gastrulation and neural fold closure. The results of the present study suggest that several chemokine molecules are related to cell movements during early morphogenesis.
Keywords: chemokine, CXC receptor, CXC ligand, gastrulation, Xenopus laevis
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 49-54 (2013)
doi: 10.1387/ijdb.120191kv / © UBC Press (www.a360grados.net)
The Wnt signaling mediator tcf1 is required for expression of foxd3 during Xenopus gastrulation
Sylvie Janssens 1,2, Olaf Van Den Broek 3, Ian R. Davenport 4, Robbert C. Akkers 5, Fei Liu 4, Gert Jan C. Veenstra 5, Stefan Hoppler 4, Kris Vleminckx 1,2 and Olivier Destrée 3.
1. Department of Biomedical Molecular Biology, Ghent University, Ghent, Belgium
2. Department for Molecular Biomedical Research, VIB, Ghent, Belgium
3. Hubrecht Institute, Utrecht, The Netherlands
4. Institute of Medical Sciences, University of Aberdeen, Aberdeen, UK
5. Department of Molecular Biology, Faculty of Science, Nijmegen Centre for Molecular Life Sciences, Radbout University Nijmegen, Nijmegen, The Netherlands.
ABSTRACT: TCF1 belongs to the family of LEF1/TCF transcription factors that regulate gene expression downstream of Wnt/β-catenin signaling, which is crucial for embryonic development and is involved in adult stem cell regulation and tumor growth. In early Xenopus embryos, tcf1 plays an important role in mesoderm induction and patterning. Foxd3 emerged as a potential tcf1 target gene in a microarray analysis of gastrula stage embryos. Because foxd3 and tcf1 are coexpressed during gastrulation, we investigated whether foxd3 is regulated by tcf1. By using morpholino-mediated knockdown, we show that during gastrulation foxd3 expression is dependent on tcf1. By chromatin immunoprecipitation, we also demonstrate direct interaction of β-catenin/tcf complexes with the foxd3 gene locus. Hence, our results indicate that tcf1 acts as an essential activator of foxd3, which is critical for dorsal mesoderm formation in early embryos.
Keywords: foxd3, lef1/tcf, tcf1, Xenopus, Wnt
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 55-60 (2013)
doi: 10.1387/ijdb.120117yk / © UBC Press (www.a360grados.net)
Microtubule disassembly prevents palatal fusion and alters regulation of the E-cadherin/catenin complex
Yukiko Kitase and Charles F. Shuler
Department of Oral Biological and Medical Sciences, Faculty of Dentistry, University of British Columbia, Vancouver BC, Canada
ABSTRACT: During palatal fusion, the midline epithelial seam (MES) degrades to achieve mesenchymal confluence. Epithelial mesenchymal transition (EMT) is one mechanism which is active in MES degradation. TGF-β induces EMT in medial edge epithelium (MEE) by down-regulation of an epithelial marker, E-cadherin. Microtubule disassembly impaired palatal fusion leading to a multi-layered MES in the mid-region. In this study, we investigated the effect of microtubule disruption on the regulation of the E-cadherin/catenin adhesion complex. Nocodazole (NDZ) enhanced the accumulation of the adhesion complex at cell-cell contacts in MEE, while loss of the adhesion complex was observed in the control. NDZ caused aberrant regulation of the E-cadherin transcriptional repressors (Snail and Zeb) and the activator (c-MYC) through inhibition of the TGF-β/SMAD2 signaling pathway, which led to a failure in EMT. These results suggest that the microtubule cytoskeleton plays an important role in mediating TGF-β/SMAD2 signals to control E-cadherin gene expression in MEE during palatal fusion.
Keywords: microtubule, palatal fusion, EMT, E-cadherin/catenin adhesion complex, TGF-β/SMAD2
Technical Article ----------------------------------------------------------------------------
EHU/UPV/UBC - The International Journal of Developmental Biology 57: 61-67 (2013)
doi: 10.1387/ijdb.120098ra / © UBC Press (www.a360grados.net)
Successful whole embryo culture with commercially available reagents
Hannah C. Glanville-Jones, Ngai Woo and Ruth M. Arkell
Early Mammalian Development Laboratory, Research School of Biology, The Australian National University, Canberra, ACT, Australia
ABSTRACT: Since its development in the 1970’s, whole embryo culture (WEC) has provided an important method of growing and observing murine embryos ex utero. During WEC, embryos are immersed in a combination of rat serum and cell culture media, and supplied with heat and appropriate mixtures of CO2 and oxygen that mimic growth conditions in utero. One significant factor limiting the widespread use of WEC is the perception that commercially produced rat serum is inadequate to support normal rates of embryonic growth and development. Conversely, production of serum ‘in-house’ is technically demanding, time-consuming and expensive. The current study aimed to identify a WEC medium comprising commercially manufactured rat serum that would produce cultured embryos of comparable standard to those grown in utero. A mixed culture medium, composed of 50% commercial rat serum and 50% F12 Ham’s cell culture medium with an N-2 neuronal cell growth supplement, was shown to support both a rate of growth, and the development of a range of features comparable to that which normally occur in vivo. Furthermore, the F12 (N-2) supplemented rat serum displayed a very low propensity to induce morphological abnormalities during the culture period. The study establishes a novel method of successful WEC using readily available commercial reagents and should enable the broader use of WEC.
Keywords: rat serum, mouse embryo culture, F12, N2
Short Communication ---------------------------------------------------------------------------
EHU/UPV/UBC - The International Journal of Developmental Biology 57: 69-72 (2013)
doi: 10.1387/ijdb.120114mm / © UBC Press (www.a360grados.net)
Innate sexuality determines the mechanisms of telomere maintenance
Kenta Tasaka 1, Naoki Yokoyama 1, Hanae Nodono 1, Motonori Hoshi 2 and Midori Matsumoto 1.
1. Department of Biological Sciences and Informatics, Keio University, Hiyoshi, Kouhoku-ku, Yokohama, Japan
2. The Open University of Japan, Wakaba, Mihama-ku, Chiba, Japan
ABSTRACT: Recently, telomere length has been shown to be differentially regulated in asexually and sexually reproducing planarians. In addition, it was found that asexual worms maintain telomere length somatically during reproduction by fission or when regeneration is induced by amputation, whereas sexual worms only achieve telomere elongation through sexual reproduction. We have established an experimental bioassay system to induce switching from asexual to sexual reproduction in planarians, that is, sexualization. In this study, the relationship between the reproductive mode and telomere maintenance was investigated using innate asexually reproducing worms, innate sexually reproducing worms, and experimentally sexualized worms. Here, we show that innate asexual planarians maintain telomere length during cell division and that innate sexual planarians exhibit telomere shortening. However, experimental sexualized worms maintain telomere length during cell division. These results indicate that innate sexuality is linked to the mechanism of telomere maintenance.
Keywords: telomere length, innate sexuality, planarian
Developmental Expression Patterns ----------------------------------------------------
EHU/UPV/UBC - The International Journal of Developmental Biology 57: 73-83 (2013)
doi: 10.1387/ijdb.120056ca / © UBC Press (www.a360grados.net)
Brachyury, Tbx2/3 and sall expression during embryogenesis of the indirectly developing polychaete Hydroides elegans
Cesar Arenas-Mena
Department of Biology, College of Staten Island and Graduate Center, The City University of New York (CUNY), NY, USA
ABSTRACT: Expression of the transcription factor genes brachyury, Tbx2/3 and sall is characterized in detail for the first time in an indirectly developing spiralian with a feeding trochophore. In Hydroides elegans, gut formation proceeds by invagination during embryogenesis and is followed by feeding-dependent posterior growth during larval stages. Posterior growth gives rise to the reproductive and segmented portion of the adult and derives primarily from multipotent dorsal blastomeres. Dorsal fate becomes morphologically evident at the 60-cell stage during spiral cleavage, although the timing of dorsal specification remains uncertain. Expression of brachyury anticipates the morphogenetic events associated with both gastrulation by invagination in the endoderm and ventral midline convergent extension in the ectoderm. The absence of brachyury expression in endoderm precursors previously reported in annelids that do not have feeding larvae suggests evolutionarily conserved roles associated with morphogenesis rather than endoderm specification. Synexpression of brachyury and FoxA in the blastopore of eumetazoans as well as in the secondarily formed anus of some protostomes and the mouth of deuterostomes suggests shared regulatory circuits during the formation of both oral and anal openings in protostomes and deuterostomes. Expression of sall during gastrulation, in the protonephridium, and in posterior growth zone precursors, also suggests evolutionarily conserved roles. The dorsal sides of the Hydroides and sea urchin embryos express Tbx2/3 in all three germ layer precursors, suggesting evolutionarily conserved dorsal regionalization functions. The results suggest specific gene usage during tubular gut formation, endoderm specification, dorsoventral specification and anteroposterior body elongation in the context of development by feeding larva.
Keywords: indirect development, spiralian, bilaterian body plan evolution, gastrulation, terminal addition
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 85-93 (2013)
doi: 10.1387/ijdb.120033gb / © UBC Press (www.a360grados.net)
Characterization and expression analysis of mcoln1.1 and mcoln1.2, the putative zebrafish co-orthologs of the gene responsible for human mucolipidosis type IV
Anna Benini 1, Andrea Bozzato 1, Silvia Mantovanelli 1, Laura Calvarini 1, Edoardo Giacopuzzi 1, Roberto Bresciani 1, Silvia Moleri 2, Daniela Zizioli 1, Monica Beltrame 2 and Giuseppe Borsani 1
1. Dipartimento di Scienze Biomediche e Biotecnologie, Universita' degli Studi di Brescia, Italy
2. Dipartimento di BioScienze, Universita' degli Studi di Milano, Milano, Italy
ABSTRACT: Mucolipidosis type IV (MLIV) is an autosomal recessive lysosomal storage disorder caused by mutations in the MCOLN1 gene coding for mucolipin-1 (TRPML1). TRPML1 belongs to a transient receptor potential channels (TRP) subfamily, which in mammals includes two other members: mucolipin-2 (TRPML2) and mucolipin-3 (TRPML3). Bioinformatic analysis of the Danio rerio (zebrafish) genome and trascriptome revealed the presence of five different genes related to human mucolipins: mcoln1.1, mcoln1.2, mcoln2, mcoln3.1 and mcoln3.2. We focused our efforts on the characterization of the two putative zebrafish MCOLN1 co-orthologs. Transient-expression experiments in human HeLa cells demonstrated that fish Mcoln1.1 and Mcoln1.2, similarly to TRPML1, localize to late endosomal/lysosomal compartments. Real-Time PCR (RT-PCR) experiments showed that both genes are maternally expressed and transcribed at different levels during embryogenesis. RT-PCR analysis in different zebrafish tissues displayed ubiquitary expression for mcoln1.1 and a more tissue-specific pattern for mcoln1.2. Spatial and temporal expression studies using whole-mount in situ hybridization confirmed that both genes are maternally expressed and ubiquitously transcribed during gastrulation and early somitogenesis. Notably, in the next developmental stages they are more expressed in neural regions and in retina layers, tissues affected in MLIV. Interestingly, mcoln1.1 is detected, from 10 somite-stage until to 36 hpf, in the yolk syncytial layer (YSL) and in the intermediate cell mass (ICM), the earliest site of hematopoiesis. Overall, the redundancy of mucolipins together with their expression profile support the biological relevance of this class of proteins in zebrafish. The data herein presented indicate that Danio rerio could be a suitable vertebrate model for the study of some aspects of MLIV pathogenesis.
Keywords: mucolipidosis type IV, mucolipin, zebrafish, TRPML1, mcoln1
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EHU/UPV/UBC - The International Journal of Developmental Biology 57: 95-100 (2013)
doi: 10.1387/ijdb.120130af / © UBC Press (www.a360grados.net)
Expression of xSDF-1α, xCXCR4, and xCXCR7 during gastrulation in Xenopus laevis
Surabhi-Kirti Mishra 1, Tomoko Nagata 1, Kazuya Furusawa 2,Naoki Sasaki 1,2 and Akimasa Fukui 1,2
1. Division of Biological Sciences, Graduate School of Science
2. Division of Advanced Interdisciplinary Science, Faculty of Advanced Life Science, Hokkaido University, Japan
ABSTRACT: Chemokines play a crucial role in developmental processes and recent studies have revealed that they also control gastrulation movements. In this paper, we report the expression patterns of xSDF-1α, xCXCR4 and xCXCR7 and regulation of the expression of xSDF-1α and xCXCR4 during gastrulation. We performed whole mount in situ hybridization (WISH) and quantitative real-time RT-PCR (qRT-PCR) analyses to examine the distribution of transcripts. The effect of activin/nodal signaling on the expression of xSDF-1α and its receptors was examined by animal cap assay and microinjection of cer-s mRNA. We have demonstrated that the xSDF-1αtranscript is increased in the blastocoel roof during gastrulation, but not in the involuted mesoderm. xCXCR4 was expressed in the mesendoderm at late blastula and was retained throughout gastrulation. xCXCR7 was found in the dorsal lip around the blastopore in the early gastrula stage and became localized in the presumptive notochord later. We also show that the expression of xCXCR4 and xSDF-1α were reciprocally regulated by activin/nodal signaling. These results suggest that xSDF-1α and its receptors contribute to the cell arrangement of mesoderm cells and their expression patterns are partially regulated by activin/nodal signaling.
Keywords: SDF-1/CXCL12, CXCR7, chemokine, gastrulation, activin/nodal signaling
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