The fate map of the cephalic neural primordium at the presomitic to the 3-somite stage in the avian embryo

Development ◽  
1988 ◽  
Vol 103 (Supplement) ◽  
pp. 101-113 ◽  
Author(s):  
GÉrard Couly ◽  
Nicole M. Le Douarin
Keyword(s):  
Experimental Design ◽  
Chick Embryo ◽  
Developmental Stage ◽  
Developmental Stages ◽  
Morphological Changes ◽  
Neural Plate ◽  
Avian Embryo ◽  
Fate Map ◽  
Marker System ◽  
Anterior Neural Plate

The fate map of the early neural plate and neural fold has been established at the cephalic level by using the quail–chick marker system (Le Douarin, 1969, 1973). The experimental design comprised the replacement of definite territories belonging to the neural plate and neural folds in the chick embryo by their counterparts from quail embryos at the same developmental stage. This technique is referred to as the isotopic and isochronic exchange of preneural tissues between these two species. The various types of experiments that were carried out are schematized in Fig. 2. The possibility of distinguishing quail from chick cells by the structure of their nuclei allowed the fate of the grafted territories to be recognized at later developmental stages ranging from 3 to 9 days of incubation (E3–E9). Fig. 1 illustrates the morphological changes in the anterior neural plate and neural ridges in the chick embryo at the early somitic stages.

Ectodermal patterning in the avian embryo: epidermis versus neural plate

Development ◽  
1999 ◽  
Vol 126 (1) ◽  
pp. 63-73 ◽  
Author(s):  
E. Pera ◽  
S. Stein ◽  
M. Kessel
Keyword(s):  
Chick Embryo ◽  
Neural Crest ◽  
Plate Boundary ◽  
Homeobox Gene ◽  
Primitive Streak ◽  
Neural Plate ◽  
Avian Embryo ◽  
Neural Fate ◽  
Early Stages ◽  
Two Factors

Ectodermal patterning of the chick embryo begins in the uterus and continues during gastrulation, when cells with a neural fate become restricted to the neural plate around the primitive streak, and cells fated to become the epidermis to the periphery. The prospective epidermis at early stages is characterized by the expression of the homeobox gene DLX5, which remains an epidermal marker during gastrulation and neurulation. Later, some DLX5-expressing cells become internalized into the ventral forebrain and the neural crest at the hindbrain level. We studied the mechanism of ectodermal patterning by transplantation of Hensen's nodes and prechordal plates. The DLX5 marker indicates that not only a neural plate, but also a surrounding epidermis is induced in such operations. Similar effects can be obtained with neural plate grafts. These experiments demonstrate that the induction of a DLX5-positive epidermis is triggered by the midline, and the effect is transferred via the neural plate to the periphery. By repeated extirpations of the endoderm we suppressed the formation of an endoderm/mesoderm layer under the epiblast. This led to the generation of epidermis, and to the inhibition of neuroepithelium in the naked ectoderm. This suggests a signal necessary for neural, but inhibitory for epidermal development, normally coming from the lower layers. Finally, we demonstrate that BMP4, as well as BMP2, is capable of inducing epidermal fate by distorting the epidermis-neural plate boundary. This, however, does not happen independently within the neural plate or outside the normal DLX5 domain. In the area opaca, the co-transplantation of a BMP4 bead with a node graft leads to the induction of DLX5, thus indicating the cooperation of two factors. We conclude that ectodermal patterning is achieved by signalling both from the midline and from the periphery, within the upper but also from the lower layers.

scholarly journals MORPHOLOGICAL CHANGES DURING THE DEVELOPMENT OF SOMATIC EMBRYOS OF SAGO (Metroxylon sagu Rottb.)

2016 ◽  
Vol 8 (2) ◽  
pp. 43 ◽  
Author(s):  
Pauline D. Kasi ◽  
Sumaryono Sumaryono
Keyword(s):  
Developmental Stage ◽  
Somatic Embryos ◽  
Large Scale ◽  
Developmental Stages ◽  
Morphological Changes ◽  
Petri Dish ◽  
Synthetic Seed ◽  
Globular Embryos ◽  
Metroxylon Sagu

Development of somatic embryos of sago (Metroxylon sagu Rottb.) on agar-solidified medium are highly varied producing heterogeneous seedlings. Understanding of this phenomenon may help in improving the cultural procedures and conditions of sago<br />somatic embryogenesis to obtain uniform seedlings in a large scale. This experiment was conducted at the laboratory for plant cell culture and micropropagation, Indonesian Biotechnology Research Institute for Estate Crops from January to March 2006 to examine morphological changes i.e. color and development stages of sago during their somatic embryo development on an agar-solidified medium. Twenty single globular somatic embryos of sago with specific color (yellowish, greenish, and reddish) were cultured in a Petri dish supplemented with a solid medium. The medium was a micronutrients-modified MS (MMS) with half strength of macronutrients containing 0.01 mg l-1 ABA, 2 mg l-1 kinetin, 20 g l-1 sucrose, 0.5 g l-1 activated charcoal, and 2 g l-1 gelrite. Parameter observed was the percentage of embryo’s number based on color and developmental stage. The result showed that at the end of 6-week culture passage, most originally greenish (80.8%) and reddish (95.8%) embryos remained unchanged in their colors, whereas almost half of the originally yellowish embryos turned to greenish and only 30%<br />remained yellowish. At the same time, single globular embryos have changed gradually into the next developmental stages, although not all of the embryos were germinated. The initial color of embryo affected the rate of the developmental stage changes. Yellowish and greenish globular embryos developed more rapidly into cotyledon or germinant stages at 58% and 55% respectively, in 6 weeks than the reddish ones (41%). Therefore, the yellowish and greenish embryos are the best sources of material for in vitro mass propagation and synthetic seed production of sago.

scholarly journals MORPHOLOGICAL CHANGES DURING THE DEVELOPMENT OF SOMATIC EMBRYOS OF SAGO (Metroxylon sagu Rottb.)

2016 ◽  
Vol 8 (2) ◽  
pp. 43
Author(s):  
Pauline D. Kasi ◽  
Sumaryono Sumaryono
Keyword(s):  
Developmental Stage ◽  
Somatic Embryos ◽  
Large Scale ◽  
Developmental Stages ◽  
Morphological Changes ◽  
Petri Dish ◽  
Synthetic Seed ◽  
Globular Embryos ◽  
Metroxylon Sagu

Development of somatic embryos of sago (Metroxylon sagu Rottb.) on agar-solidified medium are highly varied producing heterogeneous seedlings. Understanding of this phenomenon may help in improving the cultural procedures and conditions of sago<br />somatic embryogenesis to obtain uniform seedlings in a large scale. This experiment was conducted at the laboratory for plant cell culture and micropropagation, Indonesian Biotechnology Research Institute for Estate Crops from January to March 2006 to examine morphological changes i.e. color and development stages of sago during their somatic embryo development on an agar-solidified medium. Twenty single globular somatic embryos of sago with specific color (yellowish, greenish, and reddish) were cultured in a Petri dish supplemented with a solid medium. The medium was a micronutrients-modified MS (MMS) with half strength of macronutrients containing 0.01 mg l-1 ABA, 2 mg l-1 kinetin, 20 g l-1 sucrose, 0.5 g l-1 activated charcoal, and 2 g l-1 gelrite. Parameter observed was the percentage of embryo’s number based on color and developmental stage. The result showed that at the end of 6-week culture passage, most originally greenish (80.8%) and reddish (95.8%) embryos remained unchanged in their colors, whereas almost half of the originally yellowish embryos turned to greenish and only 30%<br />remained yellowish. At the same time, single globular embryos have changed gradually into the next developmental stages, although not all of the embryos were germinated. The initial color of embryo affected the rate of the developmental stage changes. Yellowish and greenish globular embryos developed more rapidly into cotyledon or germinant stages at 58% and 55% respectively, in 6 weeks than the reddish ones (41%). Therefore, the yellowish and greenish embryos are the best sources of material for in vitro mass propagation and synthetic seed production of sago.

scholarly journals Spatio-temporal selection of reference genes in the two congeneric species of Glycyrrhiza

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuping Li ◽  
Xiaoju Liang ◽  
Xuguo Zhou ◽  
Yu An ◽  
Ming Li ◽  
...  
Keyword(s):  
Gene Expression ◽  
Developmental Stage ◽  
Reference Genes ◽  
Developmental Stages ◽  
Individual Factors ◽  
Congeneric Species ◽  
Spatio Temporal ◽  
The Stability ◽  
Different Tissues ◽  
Selection Of

AbstractGlycyrrhiza, a genus of perennial medicinal herbs, has been traditionally used to treat human diseases, including respiratory disorders. Functional analysis of genes involved in the synthesis, accumulation, and degradation of bioactive compounds in these medicinal plants requires accurate measurement of their expression profiles. Reverse transcription quantitative real-time PCR (RT-qPCR) is a primary tool, which requires stably expressed reference genes to serve as the internal references to normalize the target gene expression. In this study, the stability of 14 candidate reference genes from the two congeneric species G. uralensis and G. inflata, including ACT, CAC, CYP, DNAJ, DREB, EF1, RAN, TIF1, TUB, UBC2, ABCC2, COPS3, CS, R3HDM2, were evaluated across different tissues and throughout various developmental stages. More importantly, we investigated the impact of interactions between tissue and developmental stage on the performance of candidate reference genes. Four algorithms, including geNorm, NormFinder, BestKeeper, and Delta Ct, were used to analyze the expression stability and RefFinder, a comprehensive software, provided the final recommendation. Based on previous research and our preliminary data, we hypothesized that internal references for spatio-temporal gene expression are different from the reference genes suited for individual factors. In G. uralensis, the top three most stable reference genes across different tissues were R3HDM2, CAC and TUB, while CAC, CYP and ABCC2 were most suited for different developmental stages. CAC is the only candidate recommended for both biotic factors, which is reflected in the stability ranking for the spatio (tissue)-temporal (developmental stage) interactions (CAC, R3HDM2 and DNAJ). Similarly, in G. inflata, COPS3, R3HDM2 and DREB were selected for tissues, while RAN, COPS3 and CS were recommended for developmental stages. For the tissue-developmental stage interactions, COPS3, DREB and ABCC2 were the most suited reference genes. In both species, only one of the top three candidates was shared between the individual factors and their interactions, specifically, CAC in G. uralensis and COPS3 in G. inflata, which supports our overarching hypothesis. In summary, spatio-temporal selection of reference genes not only lays the foundation for functional genomics research in Glycyrrhiza, but also facilitates these traditional medicinal herbs to reach/maximize their pharmaceutical potential.

scholarly journals Hallmarks of primary neurulation are conserved in the zebrafish forebrain

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Jonathan M. Werner ◽  
Maraki Y. Negesse ◽  
Dominique L. Brooks ◽  
Allyson R. Caldwell ◽  
Jafira M. Johnson ◽  
...  
Keyword(s):  
Neural Tube ◽  
Time Lapse ◽  
Neural Plate ◽  
Neural Tube Closure ◽  
Developmental Studies ◽  
Underlying Causes ◽  
The Central Nervous System ◽  
Resolution Imaging ◽  
Fold Formation ◽  
Anterior Neural Plate

AbstractPrimary neurulation is the process by which the neural tube, the central nervous system precursor, is formed from the neural plate. Incomplete neural tube closure occurs frequently, yet underlying causes remain poorly understood. Developmental studies in amniotes and amphibians have identified hingepoint and neural fold formation as key morphogenetic events and hallmarks of primary neurulation, the disruption of which causes neural tube defects. In contrast, the mode of neurulation in teleosts has remained highly debated. Teleosts are thought to have evolved a unique mode of neurulation, whereby the neural plate infolds in absence of hingepoints and neural folds, at least in the hindbrain/trunk where it has been studied. Using high-resolution imaging and time-lapse microscopy, we show here the presence of these morphological landmarks in the zebrafish anterior neural plate. These results reveal similarities between neurulation in teleosts and other vertebrates and hence the suitability of zebrafish to understand human neurulation.

scholarly journals Transcriptome analysis identifies differentially expressed genes in the progenies of a cross between two low phytic acid soybean mutants

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hangxia Jin ◽  
Xiaomin Yu ◽  
Qinghua Yang ◽  
Xujun Fu ◽  
Fengjie Yuan
Keyword(s):  
Developmental Stage ◽  
Phytic Acid ◽  
Differentially Expressed Genes ◽  
Transcriptome Analysis ◽  
Defense Mechanisms ◽  
Developmental Stages ◽  
Sucrose Metabolism ◽  
Differentially Expressed ◽  
Sequencing Analysis ◽  
Seed Developmental Stage

AbstractPhytic acid (PA) is a major antinutrient that cannot be digested by monogastric animals, but it can decrease the bioavailability of micronutrients (e.g., Zn and Fe). Lowering the PA content of crop seeds will lead to enhanced nutritional traits. Low-PA mutant crop lines carrying more than one mutated gene (lpa) have lower PA contents than mutants with a single lpa mutant gene. However, little is known about the link between PA pathway intermediates and downstream regulatory activities following the mutation of these genes in soybean. Consequently, we performed a comparative transcriptome analysis using an advanced generation recombinant inbred line with low PA levels [2mlpa (mips1/ipk1)] and a sibling line with homozygous non-mutant alleles and normal PA contents [2MWT (MIPS1/IPK1)]. An RNA sequencing analysis of five seed developmental stages revealed 7945 differentially expressed genes (DEGs) between the 2mlpa and 2MWT seeds. Moreover, 3316 DEGs were associated with 128 metabolic and signal transduction pathways and 4980 DEGs were annotated with 345 Gene Ontology terms related to biological processes. Genes associated with PA metabolism, photosynthesis, starch and sucrose metabolism, and defense mechanisms were among the DEGs in 2mlpa. Of these genes, 36 contributed to PA metabolism, including 22 genes possibly mediating the low-PA phenotype of 2mlpa. The expression of most of the genes associated with photosynthesis (81 of 117) was down-regulated in 2mlpa at the late seed developmental stage. In contrast, the expression of three genes involved in sucrose metabolism was up-regulated at the late seed developmental stage, which might explain the high sucrose content of 2mlpa soybeans. Furthermore, 604 genes related to defense mechanisms were differentially expressed between 2mlpa and 2MWT. In this study, we detected a low PA content as well as changes to multiple metabolites in the 2mlpa mutant. These results may help elucidate the regulation of metabolic events in 2mlpa. Many genes involved in PA metabolism may contribute to the substantial decrease in the PA content and the moderate accumulation of InsP3–InsP5 in the 2mlpa mutant. The other regulated genes related to photosynthesis, starch and sucrose metabolism, and defense mechanisms may provide additional insights into the nutritional and agronomic performance of 2mlpa seeds.

scholarly journals A gene regulatory network that underlies the derivation of the anterior neural plate from the epiblast

2010 ◽  
Vol 344 (1) ◽  
pp. 495
Author(s):  
Makiko Iwafuchi-Doi ◽  
Tatsuya Takemoto ◽  
Yuzo Yoshida ◽  
Isao Matsuo ◽  
Jun Aruga ◽  
...  
Keyword(s):  
Gene Regulatory Network ◽  
Regulatory Network ◽  
Neural Plate ◽  
Gene Regulatory ◽  
Anterior Neural Plate

scholarly journals Safe-Site Effects on Rhizosphere Bacterial Communities in a High-Altitude Alpine Environment

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Sonia Ciccazzo ◽  
Alfonso Esposito ◽  
Eleonora Rolli ◽  
Stefan Zerbe ◽  
Daniele Daffonchio ◽  
...  
Keyword(s):  
High Altitude ◽  
Developmental Stage ◽  
Bacterial Communities ◽  
Developmental Stages ◽  
Gene Diversity ◽  
Intergenic Spacer ◽  
Intermediate Stage ◽  
Plant Colonization ◽  
Early Developmental Stage ◽  
Rrna Gene

The rhizosphere effect on bacterial communities associated with three floristic communities (RW, FI, and M sites) which differed for the developmental stages was studied in a high-altitude alpine ecosystem. RW site was an early developmental stage, FI was an intermediate stage, M was a later more matured stage. The N and C contents in the soils confirmed a different developmental stage with a kind of gradient from the unvegetated bare soil (BS) site through RW, FI up to M site. The floristic communities were composed of 21 pioneer plants belonging to 14 species. Automated ribosomal intergenic spacer analysis showed different bacterial genetic structures per each floristic consortium which differed also from the BS site. When plants of the same species occurred within the same site, almost all their bacterial communities clustered together exhibiting a plant species effect. Unifrac significance value (P<0.05) on 16S rRNA gene diversity revealed significant differences (P<0.05) between BS site and the vegetated sites with a weak similarity to the RW site. The intermediate plant colonization stage FI did not differ significantly from the RW and the M vegetated sites. These results pointed out the effect of different floristic communities rhizospheres on their soil bacterial communities.

Demonstration of a phagocytic cell system belonging to the hemopoietic lineage and originating from the yolk sac in the early avian embryo

Development ◽  
1992 ◽  
Vol 115 (1) ◽  
pp. 157-168 ◽  
Author(s):  
M.A. Cuadros ◽  
P. Coltey ◽  
M. Carmen Nieto ◽  
C. Martin
Keyword(s):  
Acid Phosphatase ◽  
Developmental Stages ◽  
Cell Lineage ◽  
Cell System ◽  
Yolk Sac ◽  
Double Labelling ◽  
Avian Embryo ◽  
Phagocytic Cell ◽  
Phagocytic Capacity ◽  
Hemopoietic Cells

It is well established that hemopoietic cells arising from the yolk sac invade the avian embryo. To study the fate and role of these cells during the first 2.5-4.5 days of incubation, we constructed yolk sac chimeras (a chick embryo grafted on a quail yolk sac and vice versa) and immunostained them with antibodies specific to cells of quail hemangioblastic lineage (MB1 and QH1). This approach revealed that endothelial cells of the embryonic vessels are of intraembryonic origin. In contrast, numerous hemopoietic cells of yolk sac origin were seen in embryos ranging from 2.5 to 4.5 days of incubation. These cells were already present within the vessels and in the mesenchyme at the earliest developmental stages analyzed. Two hemopoietic cell types of yolk sac origin were distinguishable, undifferentiated cells and macrophage-like cells. The number of the latter cells increased progressively as development proceeded, and they showed marked acid phosphatase activity and phagocytic capacity, as revealed by the presence of numerous phagocytic inclusions in their cytoplasm. The macrophage-like cells were mostly distributed in the mesenchyme and also appeared within some organ primordia such as the neural tube, the liver anlage and the nephric rudiment. Comparison of the results in the two types of chimeras and the findings obtained with acid phosphatase/MB1 double labelling showed that some hemopoietic macrophage-like cells of intraembryonic origin were also present at the stages considered. These results support the existence in the early avian embryo of a phagocytic cell system of blood cell lineage, derived chiefly from the yolk sac. Cells belonging to this system perform phagocytosis in cell death and may also be involved in other morphogenetic processes.

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