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Weronika Rupik - One of the best experts on this subject based on the ideXlab platform.
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Development of the squamate naso-palatal complex: detailed 3D analysis of the vomeroNasal organ and Nasal cavity in the brown anole Anolis sagrei (Squamata: Iguania)
Frontiers in Zoology, 2020Co-Authors: Paweł Kaczmarek, Katarzyna Janiszewska, Brian Metscher, Weronika RupikAbstract:Background DesPite the diverse morphology of the adult squamate naso-palatal complex – consisting of the Nasal cavity, vomeroNasal organ (VNO), choanal groove, lacrimal duct and superficial palate – little is known about the embryology of these structures. Moreover, there are no comprehensive studies concerning development of the Nasal cavity and VNO in relation to the superficial palate. In this investigation, we used X-ray microtomography and histological sections to describe embryonic development of the naso-palatal complex of iguanian lizard, the brown anole ( Anolis sagrei ). The purpose of the study was to describe the mechanism of formation of adult morphology in this species, which combines the peculiar anole features with typical iguanian conditions. Considering the uncertain phylogenetic position of the Iguania within Squamata, embryological data and future comparative studies may shed new light on the evolution of this large squamate clade. Results Development of the naso-palatal complex was divided into three phases: early, middle and late. In the early developmental phase, the vomeroNasal Pit originates from medial outpocketing of the Nasal Pit, when the facial prominences are weakly developed. In the middle developmental phase, the following events can be noted: the formation of the frontoNasal mass, separation of the vestibulum, appearance of the lacrimal duct, and formation of the choanal groove, which leads to separation of the VNO from the Nasal cavity. In late development, the Nasal cavity and the VNO attain their adult morphology. The lacrimal duct establishes an extensive connection with the choanal groove, which eventually becomes largely separated from the oral cavity. Conclusions Unlike in other tetrapods, the primordium of the lacrimal duct in the brown anole develops largely beyond the nasolacrimal groove. In contrast to previous studies on squamates, the maxillary prominence is found to participate in the initial fusion with the frontoNasal mass. Moreover, formation of the choanal groove occurs due to the fusion of the vomerine cushion to the subconchal fold, rather than to the choanal fold. The loss or significant reduction of the lateral Nasal concha is secondary. Some features of anole adult morphology, such as the closure of the choanal groove, may constitute adaptations to vomeroNasal chemoreception.
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Development of the squamate naso-palatal complex: detailed 3D analysis of the vomeroNasal organ and Nasal cavity in the brown anole Anolis sagrei (Squamata: Iguania)
Frontiers in zoology, 2020Co-Authors: Paweł Kaczmarek, Katarzyna Janiszewska, Brian Metscher, Weronika RupikAbstract:DesPite the diverse morphology of the adult squamate naso-palatal complex – consisting of the Nasal cavity, vomeroNasal organ (VNO), choanal groove, lacrimal duct and superficial palate – little is known about the embryology of these structures. Moreover, there are no comprehensive studies concerning development of the Nasal cavity and VNO in relation to the superficial palate. In this investigation, we used X-ray microtomography and histological sections to describe embryonic development of the naso-palatal complex of iguanian lizard, the brown anole (Anolis sagrei). The purpose of the study was to describe the mechanism of formation of adult morphology in this species, which combines the peculiar anole features with typical iguanian conditions. Considering the uncertain phylogenetic position of the Iguania within Squamata, embryological data and future comparative studies may shed new light on the evolution of this large squamate clade. Development of the naso-palatal complex was divided into three phases: early, middle and late. In the early developmental phase, the vomeroNasal Pit originates from medial outpocketing of the Nasal Pit, when the facial prominences are weakly developed. In the middle developmental phase, the following events can be noted: the formation of the frontoNasal mass, separation of the vestibulum, appearance of the lacrimal duct, and formation of the choanal groove, which leads to separation of the VNO from the Nasal cavity. In late development, the Nasal cavity and the VNO attain their adult morphology. The lacrimal duct establishes an extensive connection with the choanal groove, which eventually becomes largely separated from the oral cavity. Unlike in other tetrapods, the primordium of the lacrimal duct in the brown anole develops largely beyond the nasolacrimal groove. In contrast to previous studies on squamates, the maxillary prominence is found to participate in the initial fusion with the frontoNasal mass. Moreover, formation of the choanal groove occurs due to the fusion of the vomerine cushion to the subconchal fold, rather than to the choanal fold. The loss or significant reduction of the lateral Nasal concha is secondary. Some features of anole adult morphology, such as the closure of the choanal groove, may constitute adaptations to vomeroNasal chemoreception.
Andrew Lumsden - One of the best experts on this subject based on the ideXlab platform.
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The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum
Mechanisms of Development, 2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this acne is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic-parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.
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The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum.
Mechanisms of development, 2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this gene is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic-parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit.
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Gene expression pattern The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum
2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this gene is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic– parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit. q 2002 Elsevier Science Ireland Ltd. All rights reserved.
Joy M. Richman - One of the best experts on this subject based on the ideXlab platform.
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Expression of WNT signalling pathway genes during chicken craniofacial development
Developmental dynamics : an official publication of the American Association of Anatomists, 2009Co-Authors: Poongodi Geetha-loganathan, Cheryl J. Whiting, Suresh Nimmagadda, Laurent Antoni, Philippa Francis-west, Joy M. RichmanAbstract:A comprehensive expression analysis of WNT signalling pathway genes during several stages of chicken facial development was performed. Thirty genes were surveyed including: WNT1, 2B, 3A, 4, 5A, 5B, 6, 7A, 7B, 8B, 8C, 9A, 9B, 11, 11B, 16, CTNNB1, LEF1, FRZB1, DKK1, DKK2, FZD1-8, FZD10. The strictly canonical WNTs (2B, 7A, 9B, and 16) in addition to WNT4 WNT6 (both canonical and non-canonical) are ePithelially expressed, whereas WNT5A, 5B, 11 are limited to the mesenchyme. WNT16 is limited to the invaginating Nasal Pit, respiratory ePithelium, and lip fusion zone. Antagonists DKK1 and FRZB1 are expressed in the fusing primary palate but then are decreased at stage 28 when fusion is beginning. This suggests that canonical WNT signalling may be active during lip fusion. Mediators of canonical signalling, CTNNB1, LEF1, and the majority of the FZD genes are expressed ubiquitously. These data show that activation of the canonical WNT pathway is feasible in all regions of the face; however, the localization of ligands and antagonists confers specificity. Developmental Dynamics 238:1150–1165, 2009. © 2009 Wiley-Liss, Inc.
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Novel skeletogenic patterning roles for the olfactory Pit.
Development (Cambridge England), 2008Co-Authors: Heather L. Szabo-rogers, Poongodi Geetha-loganathan, Cheryl J. Whiting, Suresh Nimmagadda, Joy M. RichmanAbstract:The position of the olfactory placodes suggests that these ePithelial thickenings might provide morphogenetic information to the adjacent facial mesenchyme. To test this, we performed in ovo manipulations of the Nasal placode in the avian embryo. Extirpation of placodal ePithelium or placement of barriers on the lateral side of the placode revealed that the main influence is on the lateral Nasal, not the frontoNasal, mesenchyme. These early effects were consistent with the subsequent deletion of lateral Nasal skeletal derivatives. We then showed in rescue experiments that FGFs are required for Nasal capsule morphogenesis. The instructive capacity of the Nasal Pit ePithelium was tested in a series of grafts to the face and trunk. Here, we showed for the first time that Nasal Pits are capable of inducing bone, cartilage and ectopic PAX7 expression, but these effects were only observed in the facial grafts. Facial mesenchyme also supported the initial projection of the olfactory nerve and differentiation of the olfactory ePithelium. Thus, the Nasal placode has two roles: as a signaling center for the lateral Nasal skeleton and as a source of olfactory neurons and sensory ePithelium.
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Control of retinoic acid synthesis and FGF expression in the Nasal Pit is required to pattern the craniofacial skeleton
Developmental biology, 2004Co-Authors: Y. Song, J.n. Hui, Joy M. RichmanAbstract:Endogenous retinoids are important for patterning many aspects of the embryo including the branchial arches and frontoNasal region of the embryonic face. The Nasal placodes express retinaldehyde dehydrogenase-3 (RALDH3) and thus retinoids from the placode are a potential patterning influence on the developing face. We have carried out experiments that have used Citral, a RALDH antagonist, to address the function of retinoid signaling from the Nasal Pit in a whole embryo model. When Citral-soaked beads were implanted into the Nasal Pit of stage 20 chicken embryos, the result was a specific loss of derivatives from the lateral Nasal prominences. Providing exogenous retinoic acid residue development of the beak demonstrating that most Citral-induced defects were produced by the specific blocking of RA synthesis. The mechanism of Citral effects was a specific increase in programmed cell death on the lateral (lateral Nasal prominence) but not the medial side (frontoNasal mass) of the Nasal Pit. Gene expression studies were focused on the Bone Morphogenetic Protein (BMP) pathway, which has a well-established role in programmed cell death. Unexpectedly, blocking RA synthesis decreased rather than increased Msx1, Msx2, and Bmp4 expression. We also examined cell survival genes, the most relevant of which was Fgf8, which is expressed around the Nasal Pit and in the frontoNasal mass. We found that Fgf8 was not initially expressed along the lateral side of the Nasal Pit at the start of our experiments, whereas it was expressed on the medial side. Citral prevented upregulation of Fgf8 along the lateral edge and this may have contributed to the specific increase in programmed cell death in the lateral Nasal prominence. Consistent with this idea, exogenous FGF8 was able to prevent cell death, rescue most of the morphological defects and was able to prevent a decrease in retinoic acid receptorbeta (Rarbeta) expression caused by Citral. Together, our results demonstrate that endogenous retinoids act upstream of FGF8 and the balance of these two factors is critical for regulating programmed cell death and morphogenesis in the face. In addition, our data suggest a novel role for endogenous retinoids from the Nasal Pit in controlling the precise downregulation of FGF in the center of the frontoNasal mass observed during normal vertebrate development.
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Chicken Transcription Factor AP-2: Cloning, Expression and Its Role in Outgrowth of Facial Prominences and Limb Buds
Developmental Biology, 1997Co-Authors: Hua Shen, Todd A. Wilke, Amir M. Ashique, Michael Narvey, Ted Zerucha, Edward Savino, Trevor Williams, Joy M. RichmanAbstract:Abstract Embryonic facial development in chick embryos involves a sequential activation of genes that control differential growth and patterning of the beak. In the present study we isolate one such gene, the transcription factor, AP-2, that is known to be expressed in the face of mouse embryos. The protein sequence of chick AP-2α is 94% homologous to human and mouse AP-2. Wholemountin situhybridization with a probe for chick AP-2 identifies expression from primitive streak stages up to stage 28. The most striking expression patterns in the head are during neural crest cell migration when AP-2 transcripts follow closely the tracts previously mapped for neural crest cells. Later, expression in the facial mesenchyme is strongest in the frontoNasal mass and lateral Nasal prominences and is downregulated in the maxillary and mandibular prominences. Once limb buds are visible, high expression is seen in the distal mesenchyme but not in the apical ectodermal ridge. The expression patterns of AP-2 in stage 20 embryos suggested that the gene may be important in “budding out” of facial prominences and limb buds. We implanted beads soaked in retinoic acid in the right Nasal Pit of stage 20 embryos resulting in a specific inhibition of outgrowth of the frontoNasal mass and lateral Nasal prominences. AP-2 expression was completely down-regulated in the lateral Nasal within 8 hr of bead application. In addition, the normal up-regulation of AP-2 in the frontoNasal mass did not occur following retinoic-acid treatment. There was an increase in programmed cell death around the right Nasal Pit that accompanied the down-regulation of AP-2. Prominences whose morphogenesis were not affected by retinoic acid did not have altered expression patterns. We removed the apical ectodermal ridge in stage 20 limb buds and found that AP-2 expression was partially downregulated 4 hr following ridge removal and completely downregulated 8 hr following stripping. Application of an FGF-4 soaked bead to the apex of the limb bud maintained AP-2 expression. Thus AP-2 is involved in outgrowth and could be regulated by factors such as FGFs that are present in the ectoderm of both the face and limb.
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Locally released retinoic acid leads to facial clefts in the chick embryo but does not alter the expression of receptors for fibroblast growth factor.
Journal of craniofacial genetics and developmental biology, 1995Co-Authors: Joy M. RichmanAbstract:Systemic administration of retinoic acid (RA) affects the growth of the upper beak of chick embryos; however, the mechanism for generating a cleft upper beak is not known. In the present study, we wished to elucidate the molecular basis of the retinoid-induced lip clefting. In order to ensure that facial prominences were locally exposed to levels of retinoid known to affect gene expression, we implanted beads soaked in different concentrations of RA in the right Nasal Pit or in the centre of the frontoNasal mass. Beads soaked in 5 mg/ml RA placed in the right Nasal Pit caused full clefting of the upper beak with a deviation of the midline toward the right side of the face. The asymmetry was principally due to a decrease in size or total elimination of the right lateral Nasal prominence. RA-soaked beads placed in the centre of the frontoNasal mass created full bilateral clefts that were more symmetrical than those produced by beads in the Nasal Pit. Lower concentrations of retinoic acid produced less severe facial abnormalities. Control experiments show that the implanted bead itself has no effect on growth or fusion of the facial prominences. The specific effects of retinoids on facial growth may be due to a localized decrease in responsiveness to growth factors. Gene expression patterns for two fibroblast growth factor receptors (Cek-2, Cek-3, [chicken embryo kinase]) in normal and RA-treated embryos were examined by in situ hybridization. In normal embryos, Cek-2 and Cek-3 transcripts are expressed at very high levels in the mesenchyme directly adjacent to the eye. Cek-3 is additionally expressed in the centre of the frontoNasal mass. The application of beads to the right Nasal Pit did not change the level of expression or distribution of transcripts for Cek-2 or Cek-3. This data suggests that retinoic acid may be affecting other aspects of the FGF receptor-ligand interaction.
Paweł Kaczmarek - One of the best experts on this subject based on the ideXlab platform.
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Development of the squamate naso-palatal complex: detailed 3D analysis of the vomeroNasal organ and Nasal cavity in the brown anole Anolis sagrei (Squamata: Iguania)
Frontiers in Zoology, 2020Co-Authors: Paweł Kaczmarek, Katarzyna Janiszewska, Brian Metscher, Weronika RupikAbstract:Background DesPite the diverse morphology of the adult squamate naso-palatal complex – consisting of the Nasal cavity, vomeroNasal organ (VNO), choanal groove, lacrimal duct and superficial palate – little is known about the embryology of these structures. Moreover, there are no comprehensive studies concerning development of the Nasal cavity and VNO in relation to the superficial palate. In this investigation, we used X-ray microtomography and histological sections to describe embryonic development of the naso-palatal complex of iguanian lizard, the brown anole ( Anolis sagrei ). The purpose of the study was to describe the mechanism of formation of adult morphology in this species, which combines the peculiar anole features with typical iguanian conditions. Considering the uncertain phylogenetic position of the Iguania within Squamata, embryological data and future comparative studies may shed new light on the evolution of this large squamate clade. Results Development of the naso-palatal complex was divided into three phases: early, middle and late. In the early developmental phase, the vomeroNasal Pit originates from medial outpocketing of the Nasal Pit, when the facial prominences are weakly developed. In the middle developmental phase, the following events can be noted: the formation of the frontoNasal mass, separation of the vestibulum, appearance of the lacrimal duct, and formation of the choanal groove, which leads to separation of the VNO from the Nasal cavity. In late development, the Nasal cavity and the VNO attain their adult morphology. The lacrimal duct establishes an extensive connection with the choanal groove, which eventually becomes largely separated from the oral cavity. Conclusions Unlike in other tetrapods, the primordium of the lacrimal duct in the brown anole develops largely beyond the nasolacrimal groove. In contrast to previous studies on squamates, the maxillary prominence is found to participate in the initial fusion with the frontoNasal mass. Moreover, formation of the choanal groove occurs due to the fusion of the vomerine cushion to the subconchal fold, rather than to the choanal fold. The loss or significant reduction of the lateral Nasal concha is secondary. Some features of anole adult morphology, such as the closure of the choanal groove, may constitute adaptations to vomeroNasal chemoreception.
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Development of the squamate naso-palatal complex: detailed 3D analysis of the vomeroNasal organ and Nasal cavity in the brown anole Anolis sagrei (Squamata: Iguania)
Frontiers in zoology, 2020Co-Authors: Paweł Kaczmarek, Katarzyna Janiszewska, Brian Metscher, Weronika RupikAbstract:DesPite the diverse morphology of the adult squamate naso-palatal complex – consisting of the Nasal cavity, vomeroNasal organ (VNO), choanal groove, lacrimal duct and superficial palate – little is known about the embryology of these structures. Moreover, there are no comprehensive studies concerning development of the Nasal cavity and VNO in relation to the superficial palate. In this investigation, we used X-ray microtomography and histological sections to describe embryonic development of the naso-palatal complex of iguanian lizard, the brown anole (Anolis sagrei). The purpose of the study was to describe the mechanism of formation of adult morphology in this species, which combines the peculiar anole features with typical iguanian conditions. Considering the uncertain phylogenetic position of the Iguania within Squamata, embryological data and future comparative studies may shed new light on the evolution of this large squamate clade. Development of the naso-palatal complex was divided into three phases: early, middle and late. In the early developmental phase, the vomeroNasal Pit originates from medial outpocketing of the Nasal Pit, when the facial prominences are weakly developed. In the middle developmental phase, the following events can be noted: the formation of the frontoNasal mass, separation of the vestibulum, appearance of the lacrimal duct, and formation of the choanal groove, which leads to separation of the VNO from the Nasal cavity. In late development, the Nasal cavity and the VNO attain their adult morphology. The lacrimal duct establishes an extensive connection with the choanal groove, which eventually becomes largely separated from the oral cavity. Unlike in other tetrapods, the primordium of the lacrimal duct in the brown anole develops largely beyond the nasolacrimal groove. In contrast to previous studies on squamates, the maxillary prominence is found to participate in the initial fusion with the frontoNasal mass. Moreover, formation of the choanal groove occurs due to the fusion of the vomerine cushion to the subconchal fold, rather than to the choanal fold. The loss or significant reduction of the lateral Nasal concha is secondary. Some features of anole adult morphology, such as the closure of the choanal groove, may constitute adaptations to vomeroNasal chemoreception.
Robindra N Gogoi - One of the best experts on this subject based on the ideXlab platform.
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The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum
Mechanisms of Development, 2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this acne is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic-parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.
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The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum.
Mechanisms of development, 2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this gene is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic-parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit.
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Gene expression pattern The paired-type homeobox gene Dmbx1 marks the midbrain and pretectum
2002Co-Authors: Robindra N Gogoi, Frank R Schubert, Juan-pedro Martinez-barbera, Dario Acampora, Antonio Simeone, Andrew LumsdenAbstract:We have isolated a paired-type homeobox gene Dmbx1, previously known as Atx (Development 128 (2001) 4789), from chick and mouse. Sequence similarity reveals that this gene is highly related to the Otx genes. Expression of Dmbx1 commences during gastrulation, when transcripts are detected in a crescent around the anterior neural plate. As development progresses, Dmbx1 marks the prospective midbrain and pretectum. Dmbx1 shares its caudal border of expression with Otx2, while expression is sharply delimited rostrally by the synencephalic– parencephalic boundary, later becoming restricted to the posterior synencephalon. At later stages, Dmbx1 is expressed in dynamic domains of the hindbrain and spinal cord. Additional sites of expression comprise stomodeal ectoderm and foregut endoderm, presomitic mesoderm, and the Nasal Pit. q 2002 Elsevier Science Ireland Ltd. All rights reserved.
