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Sample records for early embryonic development

  1. Early evolutionary trends in ammonoid embryonic development.

    PubMed

    De Baets, Kenneth; Klug, Christian; Korn, Dieter; Landman, Neil H

    2012-06-01

    During the Devonian Nekton Revolution, ammonoids show a progressive coiling of their shell just like many other pelagic mollusk groups. These now extinct, externally shelled cephalopods derived from bactritoid cephalopods with a straight shell in the Early Devonian. During the Devonian, evolutionary trends toward tighter coiling and a size reduction occurred in ammonoid embryonic shells. In at least three lineages, descendants with a closed umbilicus evolved convergently from forms with an opening in the first whorl (umbilical window). Other lineages having representatives with open umbilici became extinct around important Devonian events whereas only those with more tightly coiled embryonic shells survived. This change was accompanied by an evolutionary trend in shape of the initial chamber, but no clear trend in its size. The fact that several ammonoid lineages independently reduced and closed the umbilical window more or less synchronously indicates that common driving factors were involved. A trend in size decrease of the embryos as well as the concurrent increase in adult size in some lineages likely reflects a fundamental change in reproductive strategies toward a higher fecundity early in the evolutionary history of ammonoids. This might have played an important role in their subsequent success as well as in their demise. © 2012 The Author(s). Evolution © 2012 The Society for the Study of Evolution.

  2. [Effect of zuoguiwan on early embryonic development of mice].

    PubMed

    Feng, Q J; Feng, M L; Wang, Y L

    1996-11-01

    Effects of Zuoguiwan (ZGW, a prescription for reinforcing Kidney Yin) on early embryonic development were observed by using embryonic developmental retardation model of mice formed by alcohol. Drug was given in three ways: add ZGW into cultural medium directly (group A), add the serum of mice received ZGW (group B) and cultured the embryo taken from ZGW treated mice (group C). The result was compared with that treated with Bazhen decoction (BZD, a prescription for supplementing Qi and blood). Results showed that the in vitro developmental rate of embryo from 2-cell stage to blastula stage in group B and C, which approached to normal control group, was higher than that in untreated model obviously. While in BZW group, it was higher than in normal control group only in certain stage. However, adding ZGW directly into culture medium didn't reveal marked effect on early embryonic development.

  3. Ca2+ signalling and early embryonic patterning during zebrafish development.

    PubMed

    Webb, Sarah E; Miller, Andrew L

    2007-09-01

    1. It has been proposed that Ca2+ signalling, in the form of pulses, waves and steady gradients, may play a crucial role in key pattern-forming events during early vertebrate development. 2. With reference to the embryo of the zebrafish (Danio rerio), herein we review the Ca2+ transients reported from the cleavage to segmentation periods. This time-window includes most of the major pattern-forming events of early development, which transform a single-cell zygote into a complex multicellular embryo with established primary germ layers and body axes. 3. Data are presented to support our proposal that intracellular Ca2+ waves are an essential feature of embryonic cytokinesis and that propagating intercellular Ca2+ waves (both long and short range) may play a crucial role in: (i) the establishment of the embryonic periderm and the coordination of cell movements during epiboly, convergence and extension; (ii) the establishment of the basic embryonic axes and germ layers; and (iii) definition of the morphological boundaries of specific tissue domains and embryonic structures, including future organ anlagen. 4. The potential downstream targets of these Ca2+ transients are also discussed, as well as how they may integrate with other pattern-forming signalling pathways known to modulate early developmental events.

  4. Essential role for Max in early embryonic growth and development

    PubMed Central

    Shen-Li, Hong; O'Hagan, Rónán C.; Hou, Harry; Horner, James W.; Lee, Han-Woong; DePinho, Ronald A.

    2000-01-01

    Loss of Max function in the mouse resulted in generalized developmental arrest of both embryonic and extraembryonic tissues at early postimplantation (∼E5.5–6.5), coincident with loss or dilution of maternal Max stores in the expanding embryo in vivo and in blastocyst outgrowths in vitro. Developmentally arrested embryos were reduced in size and exhibited widespread cytological degeneration and feeble BrdU incorporation. Max and, by extension, the Myc superfamily, serve essential roles in early mammalian development and a maternal reservoir of Max exists in sufficient amount to sustain Myc superfamily function through preimplantation stages of development. PMID:10640271

  5. TRPM Channels and Magnesium in Early Embryonic Development

    PubMed Central

    Komiya, Yuko; Runnels, Loren W.

    2015-01-01

    Magnesium (Mg2+) is the second most abundant cellular cation and is essential for all stages of life, from the early embryo to adult. Mg2+ deficiency causes or contributes to many human diseases, including migraine headaches, Parkinson’s disease, Alzheimer’s disease, hypotension, type 2 diabetes mellitus and cardiac arrhythmias. Although the concentration of Mg2+ in the extracellular environment can vary significantly, the total intracellular Mg2+ concentration is actively maintained within a relatively narrow range (14 – 20 mM) via tight, yet poorly understood, regulation of intracellular Mg2+ by Mg2+ transporters and Mg2+-permeant ion channels. Recent studies have continued to add to the growing number of Mg2+ transporters and ion channels involved in Mg2+ homeostasis, including TRPM6 and TRPM7, members of the transient receptor potential (TRP) ion channel family. Mutations in TRPM6, including amino acid substitutions that prevent its heterooligomerization with TRPM7, occur in the rare autosomal-recessive disease hypomagnesemia with secondary hypocalcemia (HSH). However, is the fact that genetic ablation of either gene in mice results in early embryonic lethality that has raised the question of whether these channels’ capacity to mediate Mg2+ influx plays an important role in embryonic development. Here we review what is known of the function of Mg2+ in early development and summarize recent findings regarding the function of the TRPM6 and TRPM7 ion channels during embryogenesis. PMID:26679946

  6. Regulation of bone morphogenetic proteins in early embryonic development

    NASA Astrophysics Data System (ADS)

    Yamamoto, Yukiyo; Oelgeschläger, Michael

    2004-11-01

    Bone morphogenetic proteins (BMPs), a large subgroup of the TGF-β family of secreted growth factors, control fundamental events in early embryonic development, organogenesis and adult tissue homeostasis. The plethora of dose-dependent cellular processes regulated by BMP signalling demand a tight regulation of BMP activity. Over the last decade, a number of proteins have been identified that bind BMPs in the extracellular space and regulate the interaction of BMPs with their cognate receptors, including the secreted BMP antagonist Chordin. In the early vertebrate embryo, the localized secretion of BMP antagonists from the dorsal blastopore lip establishes a functional BMP signalling gradient that is required for the determination of the dorsoventral or back to belly body axis. In particular, inhibition of BMP activity is essential for the formation of neural tissue in the development of vertebrate and invertebrate embryos. Here we review recent studies that have provided new insight into the regulation of BMP signalling in the extracellular space. In particular, we discuss the recently identified Twisted gastrulation protein that modulates, in concert with metalloproteinases of the Tolloid family, the interaction of Chordin with BMP and a family of proteins that share structural similarities with Chordin in the respective BMP binding domains. In addition, genetic and functional studies in zebrafish and frog provide compelling evidence that the secreted protein Sizzled functionally interacts with the Chd BMP pathway, despite being expressed ventrally in the early gastrula-stage embryo. These intriguing discoveries may have important implications, not only for our current concept of early embryonic patterning, but also for the regulation of BMP activity at later developmental stages and tissue homeostasis in the adult.

  7. Dual effects of fluoxetine on mouse early embryonic development

    SciTech Connect

    Kim, Chang-Woon; Choe, Changyong; Kim, Eun-Jin; Lee, Jae-Ik; Yoon, Sook-Young; Cho, Young-Woo; Han, Sunkyu; Tak, Hyun-Min; Han, Jaehee; Kang, Dawon

    2012-11-15

    Fluoxetine, a selective serotonin reuptake inhibitor, regulates a variety of physiological processes, such as cell proliferation and apoptosis, in mammalian cells. Little is known about the role of fluoxetine in early embryonic development. This study was undertaken to investigate the effect of fluoxetine during mouse early embryonic development. Late two-cell stage embryos (2-cells) were cultured in the presence of various concentrations of fluoxetine (1 to 50 μM) for different durations. When late 2-cells were incubated with 5 μM fluoxetine for 6 h, the percentage that developed into blastocysts increased compared to the control value. However, late 2-cells exposed to fluoxetine (5 μM) over 24 h showed a reduction in blastocyst formation. The addition of fluoxetine (5 μM) together with KN93 or KN62 (calcium/calmodulin-dependent protein kinase II (CaMKII) inhibitors) failed to increase blastocyst formation. Fluoxetine treatment inhibited TREK-1 and TREK-2, members of the two-pore domain K{sup +} channel family expressed in mouse embryos, activities, indicating that fluoxetine-induced membrane depolarization in late 2-cells might have resulted from TREK inhibition. In addition, long-term exposure to fluoxetine altered the TREK mRNA expression levels. Furthermore, injection of siRNA targeting TREKs significantly decreased blastocyst formation by ∼ 30% compared to injection of scrambled siRNA. Long-term exposure of fluoxetine had no effect on blastocyst formation of TREK deficient embryos. These results indicate that low-dose and short-term exposures of late 2-cells to fluoxetine probably increase blastocyst formation through activation of CaMKII-dependent signal transduction pathways, whereas long-term exposure decreases mouse early embryonic development through inhibition of TREK channel gating. Highlights: ► Short-term exposure of 2-cells to fluoxetine enhances mouse blastocyst formation. ► The enhancive effect of fluoxetine is resulted from Ca

  8. Paternal influence of sperm DNA integrity on early embryonic development.

    PubMed

    Simon, L; Murphy, K; Shamsi, M B; Liu, L; Emery, B; Aston, K I; Hotaling, J; Carrell, D T

    2014-11-01

    Does sperm DNA damage affect early embryonic development? Increased sperm DNA damage adversely affects embryo quality starting at Day 2 of early embryonic development and continuing after embryo transfer, resulting in reduced implantation rates and pregnancy outcomes. Abnormalities in the sperm DNA in the form of single and double strand breaks can be assessed by an alkaline Comet assay. Some prior studies have shown a strong paternal effect of sperm DNA damage on IVF outcome, including reduced fertilization, reduced embryo quality and cleavage rates, reduced numbers of embryos developing into blastocysts, increased percentage of embryos undergoing developmental arrest, and reduced implantation and pregnancy rates. A cross-sectional study of 215 men from infertile couples undergoing assisted reproduction techniques at the University of Utah Center for Reproductive Medicine. Sperm from men undergoing ART were analyzed for DNA damage using an alkaline Comet assay and classified into three groups: 'low damage' (0-30%), 'intermediate damage' (31-70%) and 'high damage' (71-100%). The cause of couples' infertility was categorized into one of the three types (male, female or unexplained). Each embryo was categorized as 'good', 'fair' or 'poor' quality, based on the number and grade of blastomeres. The influence of sperm DNA damage on early embryonic development was observed and classified into four stages: peri-fertilization effect (fertilization rate), early paternal effect (embryonic days 1-2), late paternal effect (embryonic days 3-5) and implantation stage effect. The paternal effect of sperm DNA damage was observed at each stage of early embryonic development. The peri-fertilization effect was higher in oocytes from patients with female infertility (20.85%) compared with male (8.22%; P < 0.001) and unexplained (7.30%; P < 0.001) infertility factors. In both the early and late paternal effect stages, the low DNA damage group had a higher percentage of good quality

  9. Knockdown of Maternal Homeobox Transcription Factor SEBOX Gene Impaired Early Embryonic Development in Porcine Parthenotes

    PubMed Central

    ZHENG, Zhong; ZHAO, Ming-Hui; JIA, Jia-Lin; HEO, Young-Tae; CUI, Xiang-Shun; OH, Jeong Su; KIM, Nam-Hyung

    2013-01-01

    Abstract A number of germ cell-specific transcription factors essential for ovarian formation and folliculogenesis have been identified and studied. However, the role of these factors during early embryonic development has been poorly explored. In the present study, we investigated the role of SEBOX, a maternal homeobox transcription factor, during early embryonic development in porcine parthenotes. mRNA for SEBOX is preferentially expressed in oocytes, and expression persists until embryonic genome activation (EGA). Knockdown of SEBOX by siRNA disrupted early embryonic development, but not oocyte maturation. Many maternal genes essential for early embryonic development were upregulated in SEBOX-depleted embryos. Moreover, some pluripotency-associated genes, including SOX2 and NANOG, were upregulated when SEBOX was knocked down. Therefore, our data demonstrate that SEBOX is required for early embryonic development in pigs and appears to regulate the degradation of maternal transcripts and the expression of pluripotency genes. PMID:24018616

  10. Knockdown of maternal homeobox transcription factor SEBOX gene impaired early embryonic development in porcine parthenotes.

    PubMed

    Zheng, Zhong; Zhao, Ming-Hui; Jia, Jia-Lin; Heo, Young-Tae; Cui, Xiang-Shun; Oh, Jeong Su; Kim, Nam-Hyung

    2013-12-17

    A number of germ cell-specific transcription factors essential for ovarian formation and folliculogenesis have been identified and studied. However, the role of these factors during early embryonic development has been poorly explored. In the present study, we investigated the role of SEBOX, a maternal homeobox transcription factor, during early embryonic development in porcine parthenotes. mRNA for SEBOX is preferentially expressed in oocytes, and expression persists until embryonic genome activation (EGA). Knockdown of SEBOX by siRNA disrupted early embryonic development, but not oocyte maturation. Many maternal genes essential for early embryonic development were upregulated in SEBOX-depleted embryos. Moreover, some pluripotency-associated genes, including SOX2 and NANOG, were upregulated when SEBOX was knocked down. Therefore, our data demonstrate that SEBOX is required for early embryonic development in pigs and appears to regulate the degradation of maternal transcripts and the expression of pluripotency genes.

  11. Early embryonic development and transplantation in tree shrews.

    PubMed

    Yan, Lan-Zhen; Sun, Bin; Lyu, Long-Bao; Ma, Yu-Hua; Chen, Jia-Qi; Lin, Qing; Zheng, Ping; Zhao, Xu-Dong

    2016-07-18

    As a novel experimental animal model, tree shrews have received increasing attention in recent years. Despite this, little is known in regards to the time phases of their embryonic development. In this study, surveillance systems were used to record the behavior and timing of copulations; embryos at different post-copulation stages were collected and cultured in vitro; and the developmental characteristics of both early-stage and in vitro cultured embryos were determined. A total of 163 females were collected following effective copulation, and 150 were used in either unilateral or bilateral oviduct embryo collections, with 307 embryos from 111 females obtained (conception rate=74%). Among them, 237 embryos were collected from 78 females, bilaterally, i.e., the average embryo number per female was 3.04; 172 fertilized eggs collected from 55 females, bilaterally, were cultured for 24-108 h in vitro for developmental observations; finally, 65 embryos from 23 bilateral cases and 70 embryos from 33 unilateral cases were used in embryo transplantation.

  12. Early embryonic development and transplantation in tree shrews

    PubMed Central

    YAN, Lan-Zhen; SUN, Bin; LYU, Long-Bao; MA, Yu-Hua; CHEN, Jia-Qi; LIN, Qing; ZHENG, Ping; ZHAO, Xu-Dong

    2016-01-01

    As a novel experimental animal model, tree shrews have received increasing attention in recent years. Despite this, little is known in regards to the time phases of their embryonic development. In this study, surveillance systems were used to record the behavior and timing of copulations; embryos at different post-copulation stages were collected and cultured in vitro; and the developmental characteristics of both early-stage and in vitro cultured embryos were determined. A total of 163 females were collected following effective copulation, and 150 were used in either unilateral or bilateral oviduct embryo collections, with 307 embryos from 111 females obtained (conception rate=74%). Among them, 237 embryos were collected from 78 females, bilaterally, i.e., the average embryo number per female was 3.04; 172 fertilized eggs collected from 55 females, bilaterally, were cultured for 24-108 h in vitro for developmental observations; finally, 65 embryos from 23 bilateral cases and 70 embryos from 33 unilateral cases were used in embryo transplantation. PMID:27469257

  13. Oral Fertility and Early Embryonic Development Study of WR242511 Tartrate in Rats

    DTIC Science & Technology

    1995-12-21

    ORAL FERTILITY AND EARLY EMBRYONIC DEVELOPMENT STUDY OF WR242511 TARTRATE IN RATS PRECOHABITATION AND COHABITATION PHASES [ DMH SUMMARY OF WEIGHT...Classification) Oral Fertility and Early Embryonic Development Study of WR242511 Tartrate in Rats 12. PERSONAL AUTHOR(S) Levine, Barry S...This study evaluated the toxic potential of WR242511 Tartrate on reproductive capability in CD® male and female rats . WR242511 Tartrate is being

  14. Actin Cytoskeleton Contributes to the Elastic Modulus of Embryonic Tendon During Early Development

    PubMed Central

    Schiele, Nathan R.; von Flotow, Friedrich; Tochka, Zachary L.; Hockaday, Laura A.; Marturano, Joseph E.; Thibodeau, Jeffrey J.; Kuo, Catherine K.

    2016-01-01

    Tendon injuries are common and heal poorly. Strategies to regenerate or replace injured tendons are challenged by an incomplete understanding of normal tendon development. Our previous study showed that embryonic tendon elastic modulus increases as a function of developmental stage. Inhibition of enzymatic collagen crosslink formation abrogated increases in tendon elastic modulus at late developmental stages, but did not affect increases in elastic modulus of early stage embryonic tendons. Here, we aimed to identify potential contributors to the mechanical properties of these early stage embryonic tendons. We characterized tendon progenitor cells in early stage embryonic tendons, and the influence of actin cytoskeleton disruption on tissue elastic modulus. Cells were closely packed in embryonic tendons, and did not change in density during early development. We observed an organized network of actin filaments that seemed contiguous between adjacent cells. The actin filaments exhibited a crimp pattern with a period and amplitude that matched the crimp of collagen fibers at each developmental stage. Chemical disruption of the actin cytoskeleton decreased tendon tissue elastic modulus, measured by atomic force microscopy. Our results demonstrate that early developmental stage embryonic tendons possess a well organized actin cytoskeleton network that contributes significantly to tendon tissue mechanical properties. PMID:25721681

  15. Actin cytoskeleton contributes to the elastic modulus of embryonic tendon during early development.

    PubMed

    Schiele, Nathan R; von Flotow, Friedrich; Tochka, Zachary L; Hockaday, Laura A; Marturano, Joseph E; Thibodeau, Jeffrey J; Kuo, Catherine K

    2015-06-01

    Tendon injuries are common and heal poorly. Strategies to regenerate or replace injured tendons are challenged by an incomplete understanding of normal tendon development. Our previous study showed that embryonic tendon elastic modulus increases as a function of developmental stage. Inhibition of enzymatic collagen crosslink formation abrogated increases in tendon elastic modulus at late developmental stages, but did not affect increases in elastic modulus of early stage embryonic tendons. Here, we aimed to identify potential contributors to the mechanical properties of these early stage embryonic tendons. We characterized tendon progenitor cells in early stage embryonic tendons, and the influence of actin cytoskeleton disruption on tissue elastic modulus. Cells were closely packed in embryonic tendons, and did not change in density during early development. We observed an organized network of actin filaments that seemed contiguous between adjacent cells. The actin filaments exhibited a crimp pattern with a period and amplitude that matched the crimp of collagen fibers at each developmental stage. Chemical disruption of the actin cytoskeleton decreased tendon tissue elastic modulus, measured by atomic force microscopy. Our results demonstrate that early developmental stage embryonic tendons possess a well organized actin cytoskeleton network that contributes significantly to tendon tissue mechanical properties.

  16. Fertilization and early embryonic development in the porcine fallopian tube.

    PubMed

    Brüssow, K-P; Rátky, J; Rodriguez-Martinez, H

    2008-07-01

    Fertilization and early embryo development relies on a complex interplay between the Fallopian tube and the gametes before and after fertilization. Thereby the oviduct, as a dynamic reproductive organ, enables reception, transport and maturation of male and female gametes, their fusion, and supports early embryo development. This paper reviews current knowledge regarding physiological processes behind the transport of boar spermatozoa, their storage in and release from the functional sperm reservoir (SR), and of the interactions that newly ovulated oocytes play within the tube during their transport to the site of fertilization. Experimental evidence of an ovarian control on sperm release from the SR is highlighted. Furthermore, the impact of oviductal secretion on sperm capacitation, oocyte maturation, fertilization and early embryo development is stressed.

  17. The roles of ERAS during cell lineage specification of mouse early embryonic development.

    PubMed

    Zhao, Zhen-Ao; Yu, Yang; Ma, Huai-Xiao; Wang, Xiao-Xiao; Lu, Xukun; Zhai, Yanhua; Zhang, Xiaoxin; Wang, Haibin; Li, Lei

    2015-08-01

    Eras encodes a Ras-like GTPase protein that was originally identified as an embryonic stem cell-specific Ras. ERAS has been known to be required for the growth of embryonic stem cells and stimulates somatic cell reprogramming, suggesting its roles on mouse early embryonic development. We now report a dynamic expression pattern of Eras during mouse peri-implantation development: its expression increases at the blastocyst stage, and specifically decreases in E7.5 mesoderm. In accordance with its expression pattern, the increased expression of Eras promotes cell proliferation through controlling AKT activation and the commitment from ground to primed state through ERK activation in mouse embryonic stem cells; and the reduced expression of Eras facilitates primitive streak and mesoderm formation through AKT inhibition during gastrulation. The expression of Eras is finely regulated to match its roles in mouse early embryonic development during which Eras expression is negatively regulated by the β-catenin pathway. Thus, beyond its well-known role on cell proliferation, ERAS may also play important roles in cell lineage specification during mouse early embryonic development. © 2015 The Authors.

  18. Revealing the bovine embryo transcript profiles during early in vivo embryonic development.

    PubMed

    Vallée, Maud; Dufort, Isabelle; Desrosiers, Stéphanie; Labbe, Aurélie; Gravel, Catherine; Gilbert, Isabelle; Robert, Claude; Sirard, Marc-André

    2009-07-01

    Gene expression profiling is proving to be a powerful approach for the identification of molecular mechanisms underlying complex cellular functions such as the dynamic early embryonic development. The objective of this study was to perform a transcript abundance profiling analysis of bovine early embryonic development in vivo using a bovine developmental array. The molecular description of the first week of life at the mRNA level is particularly challenging when considering the important fluctuations in RNA content that occur between developmental stages. Accounting for the different intrinsic RNA content between developmental stages was achieved by restricting the reaction time during the global amplification steps and by using spiked controls and reference samples. Analysis based on intensity values revealed that most of the transcripts on the array were present at some point during in vivo bovine early embryonic development, while the varying number of genes detected in each developmental stage confirmed the dynamic profile of gene expression occurring during embryonic development. Pair-wise comparison of gene expression showed a marked difference between oocytes and blastocysts profiles, and principal component analysis revealed that the majority of the transcripts could be regrouped into three main clusters representing distinct RNA abundance profiles. Overall, these data provide a detailed temporal profile of the abundance of mRNAs revealing the richness of signaling processes in early mammalian development. Results presented here provide better knowledge of bovine in vivo embryonic development and contribute to the progression of our current knowledge regarding the first week of life in mammals.

  19. Embryonic exposure to thimerosal, an organomercury compound, causes abnormal early development of serotonergic neurons.

    PubMed

    Ida-Eto, Michiru; Oyabu, Akiko; Ohkawara, Takeshi; Tashiro, Yasura; Narita, Naoko; Narita, Masaaki

    2011-11-14

    Even though neuronal toxicity due to organomercury compounds is well known, thimerosal, an organomercury compound, is widely used in pediatric vaccine preservation. In the present study, we examined whether embryonic exposure to thimerosal affects early development of serotonergic neurons. Thimerosal (1mg Hg/kg) was intramuscularly administered to pregnant rats on gestational day 9 (susceptible time window for development of fetal serotonergic system), and fetal serotonergic neurons were assessed at embryonic day 15 using anti-serotonin antibodies. A dramatic increase in the number of serotonergic neurons localized to the lateral portion of the caudal raphe was observed in thimerosal group (1.9-fold increase, p<0.01 compared to control). These results indicate that embryonic exposure to thimerosal affects early development of serotonergic neurons.

  20. Elevated temperature enhances normal early embryonic development in the coral Platygyra acuta under low salinity conditions

    NASA Astrophysics Data System (ADS)

    Chui, Apple Pui Yi; Ang, Put

    2015-06-01

    To better understand the possible consequences of climate change on reef building scleractinian corals in a marginal environment, laboratory experiments were conducted to examine the interactive effects of changes in salinity and temperature on percent fertilization success and early embryonic development of the coral Platygyra acuta. In the present study, a salinity of 24 psu (ambient 32 psu) reduced fertilization success by 60 %. Normal embryonic development was reduced by >80 % at 26 psu (ambient 33 psu) with 100 % abnormal development at 22 psu under ambient temperature. Elevated temperature (+3 °C) above the ambient spawning temperature did not show any negative effects on fertilization success. However, there was a trend for more abnormal embryos to develop at elevated temperature in the 2 d of the spawning event. The interactive effects between salinity and temperature are statistically significant only on normal embryonic development of P. acuta, but not on its fertilization success. Salinity was revealed to be the main factor affecting both fertilization success and normal embryonic development. Interestingly, the much lower fertilization success (76 %) observed in the second day of spawning (Trial 2) under ambient temperature recovered to 99 % success under elevated (+3 °C) temperature conditions. Moreover, elevated temperature enhanced normal early embryonic development under lowered salinity (26 psu). This antagonistic interactive effect was consistently observed in two successive nights of spawning. Overall, our results indicate that, in terms of its fertilization success and embryonic development, P. acuta is the most tolerant coral species to reduced salinity thus far reported in the literature. Elevated temperature, at least that within the tolerable range of the corals, could apparently alleviate the potential negative effects from salinity stresses. This mitigating role of elevated temperature appears not to have been reported on corals before.

  1. Importance of the pluripotency factor LIN28 in the mammalian nucleolus during early embryonic development

    PubMed Central

    Vogt, Edgar J.; Meglicki, Maciej; Hartung, Kristina Ilka; Borsuk, Ewa; Behr, Rüdiger

    2012-01-01

    The maternal nucleolus is required for proper activation of the embryonic genome (EGA) and early embryonic development. Nucleologenesis is characterized by the transformation of a nucleolar precursor body (NPB) to a mature nucleolus during preimplantation development. However, the function of NPBs and the involved molecular factors are unknown. We uncover a novel role for the pluripotency factor LIN28, the biological significance of which was previously demonstrated in the reprogramming of human somatic cells to induced pluripotent stem (iPS) cells. Here, we show that LIN28 accumulates at the NPB and the mature nucleolus in mouse preimplantation embryos and embryonic stem cells (ESCs), where it colocalizes with the nucleolar marker B23 (nucleophosmin 1). LIN28 has nucleolar localization in non-human primate (NHP) preimplantation embryos, but is cytoplasmic in NHP ESCs. Lin28 transcripts show a striking decline before mouse EGA, whereas LIN28 protein localizes to NPBs at the time of EGA. Following knockdown with a Lin28 morpholino, the majority of embryos arrest between the 2- and 4-cell stages and never develop to morula or blastocyst. Lin28 morpholino-injected embryos arrested at the 2-cell stage were not enriched with nucleophosmin at presumptive NPB sites, indicating that functional NPBs were not assembled. Based on these results, we propose that LIN28 is an essential factor of nucleologenesis during early embryonic development. PMID:23172912

  2. Importance of the pluripotency factor LIN28 in the mammalian nucleolus during early embryonic development.

    PubMed

    Vogt, Edgar J; Meglicki, Maciej; Hartung, Kristina Ilka; Borsuk, Ewa; Behr, Rüdiger

    2012-12-01

    The maternal nucleolus is required for proper activation of the embryonic genome (EGA) and early embryonic development. Nucleologenesis is characterized by the transformation of a nucleolar precursor body (NPB) to a mature nucleolus during preimplantation development. However, the function of NPBs and the involved molecular factors are unknown. We uncover a novel role for the pluripotency factor LIN28, the biological significance of which was previously demonstrated in the reprogramming of human somatic cells to induced pluripotent stem (iPS) cells. Here, we show that LIN28 accumulates at the NPB and the mature nucleolus in mouse preimplantation embryos and embryonic stem cells (ESCs), where it colocalizes with the nucleolar marker B23 (nucleophosmin 1). LIN28 has nucleolar localization in non-human primate (NHP) preimplantation embryos, but is cytoplasmic in NHP ESCs. Lin28 transcripts show a striking decline before mouse EGA, whereas LIN28 protein localizes to NPBs at the time of EGA. Following knockdown with a Lin28 morpholino, the majority of embryos arrest between the 2- and 4-cell stages and never develop to morula or blastocyst. Lin28 morpholino-injected embryos arrested at the 2-cell stage were not enriched with nucleophosmin at presumptive NPB sites, indicating that functional NPBs were not assembled. Based on these results, we propose that LIN28 is an essential factor of nucleologenesis during early embryonic development.

  3. Proteomic analysis of egg white proteins during the early phase of embryonic development.

    PubMed

    Qiu, Ning; Ma, Meihu; Cai, Zhaoxia; Jin, Yongguo; Huang, Xi; Huang, Qun; Sun, Shuguo

    2012-03-16

    Avian egg albumen participates in embryonic development by providing essential nutrients as well as antimicrobial protection. Although various biological functions of egg white proteins were suggested during embryogenesis, global changes of these proteins under incubation conditions remained uninvestigated. This study presents a proteomic analysis on the change of egg white proteins during the first week of embryonic development. By using 2-DE, together with MALDI-TOF MS/MS, thirty protein spots representing eight proteins were identified showing significant changes in abundance during incubation. An accelerating degradation of ovalbumin was observed in a wide range of molecular weight. In addition, four protein complexes were predicted according to the detected molecular weight increase. Among these speculated protein complexes, an ovalbumin spot coupled with RNA-binding protein was detected. The absence of these protein complexes before incubation, followed by the constant increase in abundance during incubation indicates conceivable pivotal roles in embryonic development. To better understand the function of the proteins identified in this study, discrepancies of egg white protein changes between fertilized and unfertilized chicken eggs were additionally demonstrated. These findings will provide insight into the embryogenesis process to improve our knowledge of egg white proteins in regulating and supporting early embryonic development. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. The effect of pentoxifylline on mouse in-vitro fertilization and early embryonic development.

    PubMed

    Tournaye, H; Van der Linden, M; Van den Abbeel, E; Devroey, P; Van Steirteghem, A

    1994-10-01

    This study was designed to assess the effect of pentoxifylline (PTX) on fertilization and early embryonic development in the mouse. Oocytes from superovulated B6CBA female mice were inseminated in vitro with spermatozoa from B6CBA males incubated with PTX according to different protocols, i.e. (i) 3.6 and 7.2 mM PTX washed out prior to insemination, (ii) 3.6 and 7.2 mM PTX diluted six times in the insemination medium and (iii) PTX present at 3.6 and 7.2 mM in the insemination medium. After insemination and washing, fertilization was assessed by the presence of 2-cell stage embryos. These were further cultured up to the blastocyst or egg-cylinder stage to assess embryonic development. Parthenogenetic activation was evaluated by exposing post-ovulatory oocytes to 3.6 and 7.2 mM PTX. If spermatozoa were washed free from PTX before insemination, no effect on either fertilization or subsequent development was found. If PTX was not washed out, fertilization was reduced significantly, yet development of fertilized oocytes was unaffected. If insemination was performed in the presence of PTX both fertilization and development were impaired. Parthenogenetic activation was not increased by PTX exposure. We conclude that if used in in-vitro fertilization, exposure of oocytes and/or zygotes to PTX has to be avoided by washing out the compound thoroughly to prevent adverse effects on early embryonic development.

  5. Early embryonic development of frogs under intense magnetic fields up to 8 T

    NASA Astrophysics Data System (ADS)

    Ueno, S.; Iwasaka, M.; Shiokawa, K.

    1994-05-01

    A possible influence of intense magnetic fields on the embryonic development of frogs was studied in reference to a potential hazard in magnetic resonance imaging technology. Some of the most serious hazardous effects that could be induced by intense magnetic fields are teratogenic effects on developing embryos. In the present experiment, the possible influence of intense magnetic fields up to 8 T on the early embryonic development of Xenopus laevis was studied. Embryos were exposed to magnetic fields up to 8 T for the period from the precleavage stage to neurula in a small glass vial. Embryos were then cultured in Brown-Caston's medium until the feeding-tadpole stage. No apparent teratogenic effects were observed when embryos were cultured for 20 h from the stage of uncleaved fertilized egg to the neurula stage under magnetic fields of 8 T. We conclude that static magnetic fields up to 8 T do not appreciably affect the rapid cleavage and the following cell multiplication and differentiation in Xenopus laevis. We have also studied the early embryonic development of Xenopus laevis in a 40 nT magnetic field, or 1/1000 of the earth's magnetic field, and obtained negative results. Thus, again under this very low magnetic field, fertilized eggs developed normally and formed tadpoles with no appreciable abnormality.

  6. Dynamic Pattern of HOXB9 Protein Localization during Oocyte Maturation and Early Embryonic Development in Mammals

    PubMed Central

    Sauvegarde, Caroline; Paul, Delphine; Bridoux, Laure; Jouneau, Alice; Degrelle, Séverine; Hue, Isabelle; Rezsohazy, René; Donnay, Isabelle

    2016-01-01

    Background We previously showed that the homeodomain transcription factor HOXB9 is expressed in mammalian oocytes and early embryos. However, a systematic and exhaustive study of the localization of the HOXB9 protein, and HOX proteins in general, during mammalian early embryonic development has so far never been performed. Results The distribution of HOXB9 proteins in oocytes and the early embryo was characterized by immunofluorescence from the immature oocyte stage to the peri-gastrulation period in both the mouse and the bovine. HOXB9 was detected at all studied stages with a dynamic expression pattern. Its distribution was well conserved between the two species until the blastocyst stage and was mainly nuclear. From that stage on, trophoblastic cells always showed a strong nuclear staining, while the inner cell mass and the derived cell lines showed important dynamic variations both in staining intensity and in intra-cellular localization. Indeed, HOXB9 appeared to be progressively downregulated in epiblast cells and only reappeared after gastrulation had well progressed. The protein was also detected in the primitive endoderm and its derivatives with a distinctive presence in apical vacuoles of mouse visceral endoderm cells. Conclusions Together, these results could suggest the existence of unsuspected functions for HOXB9 during early embryonic development in mammals. PMID:27798681

  7. The zinc finger transcription factor 191 is required for early embryonic development and cell proliferation

    SciTech Connect

    Li Jianzhong; Chen Xia; Yang Hua; Wang Shuiliang; Guo Baoyu; Yu Long; Wang Zhugang; Fu Jiliang . E-mail: fu825@mail.tongji.edu.cn

    2006-12-10

    Human zinc finger protein 191 (ZNF191/ZNF24) was cloned and characterized as a SCAN family member, which shows 94% identity to its mouse homologue zinc finger protein 191 (Zfp191). ZNF191 can specifically interact with an intronic polymorphic TCAT repeat (HUMTH01) in the tyrosine hydroxylase (TH) gene. Allelic variations of HUMTH01 have been stated to have a quantitative silencing effect on TH gene expression and to correlate with quantitative and qualitative changes in the binding by ZNF191. Zfp191 is widely expressed during embryonic development and in multiple tissues and organs in adult. To investigate the functions of Zfp191 in vivo, we have used homologous recombination to generate mice that are deficient in Zfp191. Heterozygous Zfp191 {sup +/-} mice are normal and fertile. Homozygous Zfp191 {sup -/-} embryos are severely retarded in development and die at approximately 7.5 days post-fertilization. Unexpectedly, in Zfp191 {sup -/-} and Zfp191 {sup +/-} embryos, TH gene expression is not affected. Blastocyst outgrowth experiments and the RNA interference-mediated knockdown of ZNF191 in cultured cells revealed an essential role for Zfp191 in cell proliferation. In further agreement with this function, no viable Zfp191 {sup -/-} cell lines were obtained by derivation of embryonic stem (ES) cells from blastocysts of Zfp191 {sup +/-} intercrosses or by forced homogenotization of heterozygous ES cells at high concentrations of G418. These data show that Zfp191 is indispensable for early embryonic development and cell proliferation.

  8. Requirement for highly efficient pre-mRNA splicing during Drosophila early embryonic development

    PubMed Central

    Guilgur, Leonardo Gastón; Prudêncio, Pedro; Sobral, Daniel; Liszekova, Denisa; Rosa, André; Martinho, Rui Gonçalo

    2014-01-01

    Drosophila syncytial nuclear divisions limit transcription unit size of early zygotic genes. As mitosis inhibits not only transcription, but also pre-mRNA splicing, we reasoned that constraints on splicing were likely to exist in the early embryo, being splicing avoidance a possible explanation why most early zygotic genes are intronless. We isolated two mutant alleles for a subunit of the NTC/Prp19 complexes, which specifically impaired pre-mRNA splicing of early zygotic but not maternally encoded transcripts. We hypothesized that the requirements for pre-mRNA splicing efficiency were likely to vary during development. Ectopic maternal expression of an early zygotic pre-mRNA was sufficient to suppress its splicing defects in the mutant background. Furthermore, a small early zygotic transcript with multiple introns was poorly spliced in wild-type embryos. Our findings demonstrate for the first time the existence of a developmental pre-requisite for highly efficient splicing during Drosophila early embryonic development and suggest in highly proliferative tissues a need for coordination between cell cycle and gene architecture to ensure correct gene expression and avoid abnormally processed transcripts. DOI: http://dx.doi.org/10.7554/eLife.02181.001 PMID:24755291

  9. Zebrafish Noxa promotes mitosis in early embryonic development and regulates apoptosis in subsequent embryogenesis.

    PubMed

    Zhong, J-X; Zhou, L; Li, Z; Wang, Y; Gui, J-F

    2014-06-01

    Noxa functions in apoptosis and immune system of vertebrates, but its activities in embryo development remain unclear. In this study, we have studied the role of zebrafish Noxa (zNoxa) by using zNoxa-specifc morpholino knockdown and overexpression approaches in developing zebrafish embryos. Expression pattern analysis indicates that zNoxa transcript is of maternal origin, which displays a uniform distribution in early embryonic development until shield stage, and the zygote zNoxa transcription is initiated from this stage and mainly localized in YSL of the embryos. The zNoxa expression alterations result in strong embryonic development defects, demonstrating that zNoxa regulates apoptosis from 75% epiboly stage of development onward, in which zNoxa firstly induces the expression of zBik, and then cooperates with zBik to regulate apoptosis. Moreover, zNoxa knockdown also causes a reduction in number of mitotic cells before 8 h.p.f., suggesting that zNoxa also promotes mitosis before 75% epiboly stage. The effect of zNoxa on mitosis is mediated by zWnt4b in early embryos, whereas zMcl1a and zMcl1b suppress the ability of zNoxa to regulate mitosis and apoptosis at different developmental stages. In addition, mammalian mouse Noxa (mNoxa) mRNA was demonstrated to rescue the arrest of mitosis when zNoxa was knocked down, suggesting that mouse and zebrafish Noxa might have similar dual functions. Therefore, the current findings indicate that Noxa is a novel regulator of early mitosis before 75% epiboly stage when it translates into a key mediator of apoptosis in subsequent embryogenesis.

  10. Radiation hazards of radio frequency waves on the early embryonic development of Zebrafish

    NASA Astrophysics Data System (ADS)

    Harkless, Ryan; Al-Quraishi, Muntather; Vagula, Mary C.

    2014-06-01

    With the growing use of wireless devices in almost all day-to-day activities, exposure to radio-frequency radiation has become an immediate health concern. It is imperative that the effects of such radiation not only on humans, but also on other organisms be well understood. In particular, it is critical to understand if RF radiation has any bearing on the gene expression during embryonic development, as this is a crucial and delicate phase for any organism. Owing to possible effects that RF radiation may have on gene expression, it is essential to explore the carcinogenic or teratogenic properties that it may show. This study observed the effects of RF radiation emitted from a cellular telephone on the embryonic development of zebra fish. The expression of the gene shha plays a key role in the early development of the fish. This gene has homologs in humans as well as in other model organisms. Additionally, several biomarkers indicative of cell stress were examined: including lactate dehydrogenase (LDH), superoxide dismutase (SOD), and lipid peroxidation (LPO). Results show a significant decrease in the expression of shha, a significant decrease in LDH activity. There was no significant increase in SOD and LPO activity. No morphological abnormalities were observed in the developing embryos. At present, these results indicate that exposure to cell phone radiation may have a suppressive effect on expression of shha in D. rerio, though such exposure does not appear to cause morphological detriments. More trials are underway to corroborate these results.

  11. Student Learning of Early Embryonic Development via the Utilization of Research Resources from the Nematode "Caenorhabditis elegans"

    ERIC Educational Resources Information Center

    Lu, Fong-Mei; Eliceiri, Kevin W.; Squirrell, Jayne M.; White, John G.; Stewart, James

    2008-01-01

    This study was undertaken to gain insights into undergraduate students' understanding of early embryonic development, specifically, how well they comprehend the concepts of volume constancy, cell lineages, body plan axes, and temporal and spatial dimensionality in development. To study student learning, a curriculum was developed incorporating…

  12. Student Learning of Early Embryonic Development via the Utilization of Research Resources from the Nematode "Caenorhabditis elegans"

    ERIC Educational Resources Information Center

    Lu, Fong-Mei; Eliceiri, Kevin W.; Squirrell, Jayne M.; White, John G.; Stewart, James

    2008-01-01

    This study was undertaken to gain insights into undergraduate students' understanding of early embryonic development, specifically, how well they comprehend the concepts of volume constancy, cell lineages, body plan axes, and temporal and spatial dimensionality in development. To study student learning, a curriculum was developed incorporating…

  13. Variability of Gene Expression Identifies Transcriptional Regulators of Early Human Embryonic Development

    PubMed Central

    Hasegawa, Yu; Taylor, Deanne; Ovchinnikov, Dmitry A.; Wolvetang, Ernst J.; de Torrenté, Laurence; Mar, Jessica C.

    2015-01-01

    An analysis of gene expression variability can provide an insightful window into how regulatory control is distributed across the transcriptome. In a single cell analysis, the inter-cellular variability of gene expression measures the consistency of transcript copy numbers observed between cells in the same population. Application of these ideas to the study of early human embryonic development may reveal important insights into the transcriptional programs controlling this process, based on which components are most tightly regulated. Using a published single cell RNA-seq data set of human embryos collected at four-cell, eight-cell, morula and blastocyst stages, we identified genes with the most stable, invariant expression across all four developmental stages. Stably-expressed genes were found to be enriched for those sharing indispensable features, including essentiality, haploinsufficiency, and ubiquitous expression. The stable genes were less likely to be associated with loss-of-function variant genes or human recessive disease genes affected by a DNA copy number variant deletion, suggesting that stable genes have a functional impact on the regulation of some of the basic cellular processes. Genes with low expression variability at early stages of development are involved in regulation of DNA methylation, responses to hypoxia and telomerase activity, whereas by the blastocyst stage, low-variability genes are enriched for metabolic processes as well as telomerase signaling. Based on changes in expression variability, we identified a putative set of gene expression markers of morulae and blastocyst stages. Experimental validation of a blastocyst-expressed variability marker demonstrated that HDDC2 plays a role in the maintenance of pluripotency in human ES and iPS cells. Collectively our analyses identified new regulators involved in human embryonic development that would have otherwise been missed using methods that focus on assessment of the average expression

  14. Loss of function of KIF1B impairs oocyte meiotic maturation and early embryonic development in mice.

    PubMed

    Kong, Xiang-Wei; Wang, Dong-Hui; Zhou, Cheng-Jie; Zhou, Hong-Xia; Liang, Cheng-Guang

    2016-11-01

    Kinesin family member 1B (KIF1B) is an important microtubule-dependent monomeric motor in mammals, although little is known about its role in meiosis. We profiled KIF1B expression and localization during oocyte maturation and early embryonic development in mice, revealing a dynamic pattern throughout meiotic progression. Depletion or inhibition of KIF1B leads to abnormal polar body extrusion, disordered spindle dynamics, defects in chromosome congression, increased aneuploidy, and impaired embryonic development. Further, KIF1B depletion affects the distribution of mitochondria and abundance of ATP. Taken together, our study demonstrates that mouse KIF1B is important for spindle assembly, chromosome congression, and mitochondrial distribution during oocyte maturation and early embryonic development. Mol. Reprod. Dev. 83: 1027-1040, 2016 © 2016 Wiley Periodicals, Inc.

  15. Effects of temperature on embryonic and early larval growth and development in the rough-skinned newt (Taricha granulosa).

    PubMed

    Smith, Geoffrey D; Hopkins, Gareth R; Mohammadi, Shabnam; M Skinner, Heather; Hansen, Tyler; Brodie, Edmund D; French, Susannah S

    2015-07-01

    We investigated the effects of temperature on the growth and development of embryonic and early larval stages of a western North American amphibian, the rough-skinned newt (Taricha granulosa). We assigned newt eggs to different temperatures (7, 14, or 21°C); after hatching, we re-assigned the newt larvae into the three different temperatures. Over the course of three to four weeks, we measured total length and developmental stage of the larvae. Our results indicated a strong positive relationship over time between temperature and both length and developmental stage. Importantly, individuals assigned to cooler embryonic temperatures did not achieve the larval sizes of individuals from the warmer embryonic treatments, regardless of larval temperature. Our investigation of growth and development at different temperatures demonstrates carry-over effects and provides a more comprehensive understanding of how organisms respond to temperature changes during early development.

  16. Promotion of human early embryonic development and blastocyst outgrowth in vitro using autocrine/paracrine growth factors.

    PubMed

    Kawamura, Kazuhiro; Chen, Yuan; Shu, Yimin; Cheng, Yuan; Qiao, Jie; Behr, Barry; Pera, Renee A Reijo; Hsueh, Aaron J W

    2012-01-01

    Studies using animal models demonstrated the importance of autocrine/paracrine factors secreted by preimplantation embryos and reproductive tracts for embryonic development and implantation. Although in vitro fertilization-embryo transfer (IVF-ET) is an established procedure, there is no evidence that present culture conditions are optimal for human early embryonic development. In this study, key polypeptide ligands known to be important for early embryonic development in animal models were tested for their ability to improve human early embryo development and blastocyst outgrowth in vitro. We confirmed the expression of key ligand/receptor pairs in cleavage embryos derived from discarded human tri-pronuclear zygotes and in human endometrium. Combined treatment with key embryonic growth factors (brain-derived neurotrophic factor, colony-stimulating factor, epidermal growth factor, granulocyte macrophage colony-stimulating factor, insulin-like growth factor-1, glial cell-line derived neurotrophic factor, and artemin) in serum-free media promoted >2.5-fold the development of tri-pronuclear zygotes to blastocysts. For normally fertilized embryos, day 3 surplus embryos cultured individually with the key growth factors showed >3-fold increases in the development of 6-8 cell stage embryos to blastocysts and >7-fold increase in the proportion of high quality blastocysts based on Gardner's criteria. Growth factor treatment also led to a 2-fold promotion of blastocyst outgrowth in vitro when day 7 surplus hatching blastocysts were used. When failed-to-be-fertilized oocytes were used to perform somatic cell nuclear transfer (SCNT) using fibroblasts as donor karyoplasts, inclusion of growth factors increased the progression of reconstructed SCNT embryos to >4-cell stage embryos. Growth factor supplementation of serum-free cultures could promote optimal early embryonic development and implantation in IVF-ET and SCNT procedures. This approach is valuable for infertility

  17. The early embryonic expression of TFII-I during mouse preimplantation development.

    PubMed

    Enkhmandakh, Badam; Bitchevaia, Natalia; Ruddle, Frank; Bayarsaihan, Dashzeveg

    2004-01-01

    We studied the developmentally regulated expression of mouse TFII-I, a founding member of a family of transcription factors characterized by the presence of multiple helix-loop-helix repeat domains. TFII-I and BEN, a second member of this family, are involved in histone modification and SUMOylation. The genes, GTF2I and GTF2IRD1, encoding these proteins in human are located at chromosomal band 7q11.23, within the Williams syndrome critical region. Our immunohistochemical analysis revealed extensive expression of TFII-I at early stages of embryogenesis. Like BEN, TFII-I is detected in the cytoplasm and nuclei of postfertilization through first cleavage stage embryos. However, in E4.5 blastocysts, at the time of implantation, TFII-I is localized in the nucleus and cytoplasm of the inner cell mass (ICM) and trophectoderm. BEN, at this stage, is expressed only in the cytoplasm of trophoblast cells, but not in the ICM [Gene Expr. Patterns, 2003; 3, 577-587]. Using RT-PCR, we detected Gtf2i and Gtf2ird1 mRNA transcripts in unfertilized oocytes, which indicates the maternal expression of these genes. Thus, the early embryonic expression of TFII-I implicates this family of transcription factors in preimplantation development.

  18. beta-Catenin in early development of the lancelet embryo indicates specific determination of embryonic polarity.

    PubMed

    Yasui, Kinya; Li, Guorong; Wang, Yong; Saiga, Hidetoshi; Zhang, Peijun; Aizawa, Shinichi

    2002-12-01

    The lancelet (amphioxus) embryo develops from a miolecithal egg and starts gastrulation when it is approximately 400 cells in size, in a fashion similar to that of some non-chordate deuterostomes. Throughout this type of gastrulation, the embryo develops characteristics such as the notochord and hollow nerve cord that commonly appear in chordates. beta-Catenin is an important factor in initiating body patterning. The behavior and developmental pattern of this protein in early lancelet development was examined in this study. Cytoplasmic beta-catenin was localized to the animal pole after fertilization and then was incorporated asymmetrically into the blastomeres during the first cleavage. Asymmetric distribution was observed at least until the 32-cell stage. The first nuclear localization was at the 64-cell stage, and involved all of the cells. At the initial gastrula stage, however, concentrated beta-catenin was found on the dorsal side. LiCl treatment affected the asymmetric pattern of beta-catenin during the first cleavage. LiCl also changed distribution of nuclear beta-catenin at the initial gastrula stage: distribution extended to cells on the animal side. Apparently associated with this change, expression domains of goosecoid, lhx3 and otx also changed to a radially symmetric pattern centered at the animal pole. However, LiCl-treated embryos were able to establish embryonic polarity. The present study suggests that in the lancelet embryo, polarity determination is independent of dorsal morphogenesis.

  19. Regulation of embryonic size in early mouse development in vitro culture system.

    PubMed

    Hisaki, Tomoka; Kawai, Ikuma; Sugiura, Koji; Naito, Kunihiko; Kano, Kiyoshi

    2014-08-01

    Mammals self-regulate their body size throughout development. In the uterus, embryos are properly regulated to be a specific size at birth. Previously, size and cell number in aggregated embryos, which were made from two or more morulae, and half embryos, which were halved at the 2-cell stage, have been analysed in vivo in preimplantation and post-implantation development in mice. Here, we examined whether or not the mouse embryo has the capacity to self-regulate growth using an in vitro culture system. To elucidate embryonic histology, cells were counted in aggregated or half embryos in comparison with control embryos. Both double- and triple-aggregated embryos contained more cells than did control embryos during all culture periods, and the relative growth ratios showed no growth inhibition in an in vitro culture system. Meanwhile, half embryos contained fewer cells than control embryos, but the number grew throughout the culture period. Our data suggest that the growth of aggregated embryos is not affected and continues in an in vitro culture system. On the other hand, the growth of half embryos accelerates and continues in an in vitro culture system. This situation, in turn, implied that post-implantation mouse embryos might have some potential to regulate their own growth and size as seen by using an in vitro culture system without uterus factors. In conclusion, our results indicated that embryos have some ways in which to regulate their own size in mouse early development.

  20. Expression profile and thyroid hormone responsiveness of transporters and deiodinases in early embryonic chicken brain development.

    PubMed

    Van Herck, Stijn L J; Geysens, Stijn; Delbaere, Joke; Tylzanowski, Przemko; Darras, Veerle M

    2012-02-26

    We used the chick embryo to study the mechanisms regulating intracellular TH availability in developing brain. TH-transporters OATP1C1 and MCT8, and deiodinases D1, D2, and D3 were expressed in a region-specific way, well before the onset of endogenous TH secretion. Between day 4 and 10 of development MCT8 and D2 mRNA levels increased, while OATP1C1 and D3 mRNA levels decreased. D2 and D3 mRNAs were translated into active protein, while no D1 activity was detectable. Injection of THs into the yolk 24h before sampling increased TH levels in the brain and resulted in decreased OATP1C1 and increased MCT8 expression in 4-day-old embryos. A compensatory response in deiodinase activity was only observed at day 8. We conclude that THs are active in the early embryonic brain and TH-transporters and deiodinases can regulate their availability. However, the absence of clear compensatory mechanisms at day 4 makes the brain more vulnerable for changes in maternal TH supply. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  1. Alveolar flows of the developing lungs:from embryonic to early childhood airways

    NASA Astrophysics Data System (ADS)

    Tenenbaum-Katan, Janna; Hofemeier, Philipp; Fishler, Rami; Rothen-Rutishauser, Barbara; Sznitman, Josue

    2014-11-01

    At the onset of life in utero the respiratory system is simply a liquid-filled duct. With our first breath, alveoli are filled with air and become a significant port of entry for airborne particles. As such, alveolar lining is nearly fully functional at birth, though lung development continues during childhood as structural changes increase alveolar surface area to optimize ventilation. We hypothesize that such fluid dynamical changes potentially affect two phenomena occurring within alveoli: (i) flow patterns in airspaces at distinct stages of both in- and ex-utero life and (ii) fate of inhaled particles ex-utero. To investigate these phenomena, we combine experimental and numerical approaches where (i) microfluidic in vitro devices mimic liquid flows across the epithelium of fetal airspaces, and (ii) computational simulations are employed to examine particle transport and deposition in the deep alveolated regions of infants' lungs. Our approaches capture anatomically-inspired geometries based on morphometrical data, as well as physiological flows, including the convective-diffusive nature of submicron particle transport in alveolar regions.Overall, we investigate respiratory flows in alveolar regions of developing lungs, from early embryonic stages to late childhood

  2. KDM6 Demethylase Independent Loss of Histone H3 Lysine 27 Trimethylation during Early Embryonic Development

    PubMed Central

    Shpargel, Karl B.; Starmer, Joshua; Yee, Della; Pohlers, Michael; Magnuson, Terry

    2014-01-01

    The early mammalian embryo utilizes histone H3 lysine 27 trimethylation (H3K27me3) to maintain essential developmental genes in a repressive chromatin state. As differentiation progresses, H3K27me3 is removed in a distinct fashion to activate lineage specific patterns of developmental gene expression. These rapid changes in early embryonic chromatin environment are thought to be dependent on H3K27 demethylases. We have taken a mouse genetics approach to remove activity of both H3K27 demethylases of the Kdm6 gene family, Utx (Kdm6a, X-linked gene) and Jmjd3 (Kdm6b, autosomal gene). Male embryos null for active H3K27 demethylation by the Kdm6 gene family survive to term. At mid-gestation, embryos demonstrate proper patterning and activation of Hox genes. These male embryos retain the Y-chromosome UTX homolog, UTY, which cannot demethylate H3K27me3 due to mutations in catalytic site of the Jumonji-C domain. Embryonic stem (ES) cells lacking all enzymatic KDM6 demethylation exhibit a typical decrease in global H3K27me3 levels with differentiation. Retinoic acid differentiations of these ES cells demonstrate loss of H3K27me3 and gain of H3K4me3 to Hox promoters and other transcription factors, and induce expression similar to control cells. A small subset of genes exhibit decreased expression associated with reduction of promoter H3K4me3 and some low-level accumulation of H3K27me3. Finally, Utx and Jmjd3 mutant mouse embryonic fibroblasts (MEFs) demonstrate dramatic loss of H3K27me3 from promoters of several Hox genes and transcription factors. Our results indicate that early embryonic H3K27me3 repression can be alleviated in the absence of active demethylation by the Kdm6 gene family. PMID:25101834

  3. Generation of the Dimensional Embryology Application (App) for Visualization of Early Chick and Frog Embryonic Development

    ERIC Educational Resources Information Center

    Webb, Rebecca L.; Bilitski, James; Zerbee, Alyssa; Symans, Alexandra; Chop, Alexandra; Seitz, Brianne; Tran, Cindy

    2015-01-01

    The study of embryonic development of multiple organisms, including model organisms such as frogs and chicks, is included in many undergraduate biology programs, as well as in a variety of graduate programs. As our knowledge of biological systems increases and the amount of material to be taught expands, the time spent instructing students about…

  4. Embryonic, larval, and early juvenile development of the tropical sea urchin, Salmacis sphaeroides (Echinodermata: Echinoidea).

    PubMed

    Rahman, M Aminur; Yusoff, Fatimah Md; Arshad, A; Shamsudin, Mariana Nor; Amin, S M N

    2012-01-01

    Salmacis sphaeroides (Linnaeus, 1758) is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10(-5) dilution) was 96.6 ± 1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell), 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla) stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72 ± 4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition.

  5. Embryonic, Larval, and Early Juvenile Development of the Tropical Sea Urchin, Salmacis sphaeroides (Echinodermata: Echinoidea)

    PubMed Central

    Rahman, M. Aminur; Yusoff, Fatimah Md.; Arshad, A.; Shamsudin, Mariana Nor; Amin, S. M. N.

    2012-01-01

    Salmacis sphaeroides (Linnaeus, 1758) is one of the regular echinoids, occuring in the warm Indo-West Pacific, including Johor Straits, between Malaysia and Singapore. In order to investigate the developmental basis of morphological changes in embryos and larvae, we documented the ontogeny of S. sphaeroides in laboratory condition. Gametes were obtained from adult individuals by 0.5 M KCl injection into the coelomic cavity. Fertilization rate at limited sperm concentration (10−5 dilution) was 96.6 ± 1.4% and the resulting embryos were reared at 24°C. First cleavage (2-cell), 4-cell, 8-cell, 16-cell, 32-cell, and multicell (Morulla) stages were achieved 01.12, 02.03, 02.28, 02.51, 03.12, and 03.32 h postfertilization. Ciliated blastulae with a mean length of 174.72 ± 4.43 μm hatched 08.45 h after sperm entry. The gastrulae formed 16.15 h postfertilization and the archenteron elongated constantly while ectodermal red-pigmented cells migrated synchronously to the apical plate. Pluteus larva started to feed unicellular algae in 2 d, grew continuously, and finally attained metamorphic competence in 35 d after fertilization. Metamorphosis took approximately 1 h 30 min from attachment to the complete resorption of larval tissues and the development of complete juvenile structure with adult spines, extended tubefeet and well-developed pedicellaria, the whole event of which usually took place within 1 d postsettlement. This study represents the first successful investigation on embryonic, larval, and early juvenile development of S. sphaeroides. The findings would greatly be helpful towards the understanding of ontogeny and life-history strategies, which will facilitate us to develop the breeding, seed production, and culture techniques of sea urchins in captive condition. PMID:23055824

  6. Time-Series Interactions of Gene Expression, Vascular Growth and Hemodynamics during Early Embryonic Arterial Development

    PubMed Central

    Goktas, Selda; Uslu, Fazil E.; Kowalski, William J.; Ermek, Erhan; Keller, Bradley B.

    2016-01-01

    The role of hemodynamic forces within the embryo as biomechanical regulators for cardiovascular morphogenesis, growth, and remodeling is well supported through the experimental studies. Furthermore, clinical experience suggests that perturbed flow disrupts the normal vascular growth process as one etiology for congenital heart diseases (CHD) and for fetal adaptation to CHD. However, the relationships between hemodynamics, gene expression and embryonic vascular growth are poorly defined due to the lack of concurrent, sequential in vivo data. In this study, a long-term, time-lapse optical coherence tomography (OCT) imaging campaign was conducted to acquire simultaneous blood velocity, pulsatile micro-pressure and morphometric data for 3 consecutive early embryonic stages in the chick embryo. In conjunction with the in vivo growth and hemodynamics data, in vitro reverse transcription polymerase chain reaction (RT-PCR) analysis was performed to track changes in transcript expression relevant to histogenesis and remodeling of the embryonic arterial wall. Our non-invasive extended OCT imaging technique for the microstructural data showed continuous vessel growth. OCT data coupled with the PIV technique revealed significant but intermitted increases in wall shear stress (WSS) between first and second assigned stages and a noticeable decrease afterwards. Growth rate, however, did not vary significantly throughout the embryonic period. Among all the genes studied, only the MMP-2 and CASP-3 expression levels remained unchanged during the time course. Concurrent relationships were obtained among the transcriptional modulation of the genes, vascular growth and hemodynamics-related changes. Further studies are indicated to determine cause and effect relationships and reversibility between mechanical and molecular regulation of vasculogenesis. PMID:27552150

  7. Development and morphogenesis of human wrist joint during embryonic and early fetal period

    PubMed Central

    Hita-Contreras, Fidel; Martínez-Amat, Antonio; Ortiz, Raúl; Caba, Octavio; Álvarez, Pablo; Prados, José C; Lomas-Vega, Rafael; Aránega, Antonia; Sánchez-Montesinos, Indalecio; Mérida-Velasco, Juan A

    2012-01-01

    The development of the human wrist joint has been studied widely, with the main focus on carpal chondrogenesis, ligaments and triangular fibrocartilage. However, there are some discrepancies concerning the origin and morphogenetic time-table of these structures, including nerves, muscles and vascular elements. For this study we used serial sections of 57 human embryonic (n = 30) and fetal (n = 27) specimens from O’Rahilly stages 17–23 and 9–14 weeks, respectively. The following phases in carpal morphogenesis have been established: undifferentiated mesenchyme (stage 17), condensated mesenchyme (stages 18 and 19), pre-chondrogenic (stages 19 and 20) and chondrogenic (stages 21 and over). Carpal chondrification and osteogenic processes are similar, starting with capitate and hamate (stage 19) and ending with pisiform (stage 22). In week 14, a vascular bud penetrates into the lunate cartilaginous mold, early sign of the osteogenic process that will be completed after birth. In stage 18, median, ulnar and radial nerves and thenar eminence appear in the hand plate. In stage 21, there are indications of the interosseous muscles, and in stage 22 flexor digitorum superficialis, flexor digitorum profundus and lumbrical muscles, transverse carpal ligament and collateral ligaments emerge. In stage 23, the articular disc, radiocarpal and ulnocarpal ligaments and deep palmar arterial arch become visible. Radiate carpal and interosseous ligaments appear in week 9, and in week 10, dorsal radiocarpal ligament and articular capsule are evident. Finally, synovial membrane is observed in week 13. We have performed a complete analysis of the morphogenesis of the structures of the human wrist joint. Our results present new data on nervous and arterial elements and provide the basis for further investigations on anatomical pathology, comparative morphology and evolutionary anthropology. PMID:22428933

  8. Development and morphogenesis of human wrist joint during embryonic and early fetal period.

    PubMed

    Hita-Contreras, Fidel; Martínez-Amat, Antonio; Ortiz, Raúl; Caba, Octavio; Alvarez, Pablo; Prados, José C; Lomas-Vega, Rafael; Aránega, Antonia; Sánchez-Montesinos, Indalecio; Mérida-Velasco, Juan A

    2012-06-01

    The development of the human wrist joint has been studied widely, with the main focus on carpal chondrogenesis, ligaments and triangular fibrocartilage. However, there are some discrepancies concerning the origin and morphogenetic time-table of these structures, including nerves, muscles and vascular elements. For this study we used serial sections of 57 human embryonic (n = 30) and fetal (n = 27) specimens from O'Rahilly stages 17-23 and 9-14 weeks, respectively. The following phases in carpal morphogenesis have been established: undifferentiated mesenchyme (stage 17), condensated mesenchyme (stages 18 and 19), pre-chondrogenic (stages 19 and 20) and chondrogenic (stages 21 and over). Carpal chondrification and osteogenic processes are similar, starting with capitate and hamate (stage 19) and ending with pisiform (stage 22). In week 14, a vascular bud penetrates into the lunate cartilaginous mold, early sign of the osteogenic process that will be completed after birth. In stage 18, median, ulnar and radial nerves and thenar eminence appear in the hand plate. In stage 21, there are indications of the interosseous muscles, and in stage 22 flexor digitorum superficialis, flexor digitorum profundus and lumbrical muscles, transverse carpal ligament and collateral ligaments emerge. In stage 23, the articular disc, radiocarpal and ulnocarpal ligaments and deep palmar arterial arch become visible. Radiate carpal and interosseous ligaments appear in week 9, and in week 10, dorsal radiocarpal ligament and articular capsule are evident. Finally, synovial membrane is observed in week 13. We have performed a complete analysis of the morphogenesis of the structures of the human wrist joint. Our results present new data on nervous and arterial elements and provide the basis for further investigations on anatomical pathology, comparative morphology and evolutionary anthropology. © 2012 The Authors. Journal of Anatomy © 2012 Anatomical Society.

  9. Glutathione reductase gsr-1 is an essential gene required for Caenorhabditis elegans early embryonic development.

    PubMed

    Mora-Lorca, José Antonio; Sáenz-Narciso, Beatriz; Gaffney, Christopher J; Naranjo-Galindo, Francisco José; Pedrajas, José Rafael; Guerrero-Gómez, David; Dobrzynska, Agnieszka; Askjaer, Peter; Szewczyk, Nathaniel J; Cabello, Juan; Miranda-Vizuete, Antonio

    2016-07-01

    Glutathione is the most abundant thiol in the vast majority of organisms and is maintained in its reduced form by the flavoenzyme glutathione reductase. In this work, we describe the genetic and functional analysis of the Caenorhabditis elegans gsr-1 gene that encodes the only glutathione reductase protein in this model organism. By using green fluorescent protein reporters we demonstrate that gsr-1 produces two GSR-1 isoforms, one located in the cytoplasm and one in the mitochondria. gsr-1 loss of function mutants display a fully penetrant embryonic lethal phenotype characterized by a progressive and robust cell division delay accompanied by an aberrant distribution of interphasic chromatin in the periphery of the cell nucleus. Maternally expressed GSR-1 is sufficient to support embryonic development but these animals are short-lived, sensitized to chemical stress, have increased mitochondrial fragmentation and lower mitochondrial DNA content. Furthermore, the embryonic lethality of gsr-1 worms is prevented by restoring GSR-1 activity in the cytoplasm but not in mitochondria. Given the fact that the thioredoxin redox systems are dispensable in C. elegans, our data support a prominent role of the glutathione reductase/glutathione pathway in maintaining redox homeostasis in the nematode.

  10. Glycogen and Glucose Metabolism Are Essential for Early Embryonic Development of the Red Flour Beetle Tribolium castaneum

    PubMed Central

    Fraga, Amanda; Ribeiro, Lupis; Lobato, Mariana; Santos, Vitória; Silva, José Roberto; Gomes, Helga; da Cunha Moraes, Jorge Luiz; de Souza Menezes, Jackson

    2013-01-01

    Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis) and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3) and hexokinase (HexA) genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi) of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen. PMID:23750237

  11. Glycogen and glucose metabolism are essential for early embryonic development of the red flour beetle Tribolium castaneum.

    PubMed

    Fraga, Amanda; Ribeiro, Lupis; Lobato, Mariana; Santos, Vitória; Silva, José Roberto; Gomes, Helga; da Cunha Moraes, Jorge Luiz; de Souza Menezes, Jackson; de Oliveira, Carlos Jorge Logullo; Campos, Eldo; da Fonseca, Rodrigo Nunes

    2013-01-01

    Control of energy metabolism is an essential process for life. In insects, egg formation (oogenesis) and embryogenesis is dependent on stored molecules deposited by the mother or transcribed later by the zygote. In oviparous insects the egg becomes an isolated system after egg laying with all energy conversion taking place during embryogenesis. Previous studies in a few vector species showed a strong correlation of key morphogenetic events and changes in glucose metabolism. Here, we investigate glycogen and glucose metabolism in the red flour beetle Tribolium castaneum, an insect amenable to functional genomic studies. To examine the role of the key enzymes on glycogen and glucose regulation we cloned and analyzed the function of glycogen synthase kinase 3 (GSK-3) and hexokinase (HexA) genes during T. castaneum embryogenesis. Expression analysis via in situ hybridization shows that both genes are expressed only in the embryonic tissue, suggesting that embryonic and extra-embryonic cells display different metabolic activities. dsRNA adult female injection (parental RNAi) of both genes lead a reduction in egg laying and to embryonic lethality. Morphological analysis via DAPI stainings indicates that early development is impaired in Tc-GSK-3 and Tc-HexA1 RNAi embryos. Importantly, glycogen levels are upregulated after Tc-GSK-3 RNAi and glucose levels are upregulated after Tc-HexA1 RNAi, indicating that both genes control metabolism during embryogenesis and oogenesis, respectively. Altogether our results show that T. castaneum embryogenesis depends on the proper control of glucose and glycogen.

  12. Junction-mediating and regulatory protein (JMY) is essential for early porcine embryonic development.

    PubMed

    Lin, Zi Li; Cui, Xiang-Shun; Namgoong, Suk; Kim, Nam-Hyung

    2015-01-01

    Junction-mediating and regulatory protein (JMY) is a regulator of both transcription and actin filament assembly. JMY is a critical nucleation-promoting factor (NPF); however, its role in the development of mammalian embryos is poorly understood. In the current study, we investigated the functional roles of the NPF JMY in porcine embryos. Porcine embryos expressed JMY mRNA and protein, and JMY protein moved from the cytoplasm to the nucleus at later embryonic developmental stages. Knockdown of JMY by RNA interference markedly decreased the rate of blastocyst development, validating its role in the development of porcine embryos. Furthermore, injection of JMY dsRNA also impaired actin and Arp2 expression, and co-injection of actin and Arp2 mRNA partially rescued blastocyst development. Taken together, our results show that the NPF JMY is involved in the development of porcine embryos by regulating the NPF-Arp2-actin pathway.

  13. Junction-mediating and regulatory protein (JMY) is essential for early porcine embryonic development

    PubMed Central

    LIN, Zi Li; CUI, Xiang-Shun; NAMGOONG, Suk; KIM, Nam-Hyung

    2015-01-01

    Junction-mediating and regulatory protein (JMY) is a regulator of both transcription and actin filament assembly. JMY is a critical nucleation-promoting factor (NPF); however, its role in the development of mammalian embryos is poorly understood. In the current study, we investigated the functional roles of the NPF JMY in porcine embryos. Porcine embryos expressed JMY mRNA and protein, and JMY protein moved from the cytoplasm to the nucleus at later embryonic developmental stages. Knockdown of JMY by RNA interference markedly decreased the rate of blastocyst development, validating its role in the development of porcine embryos. Furthermore, injection of JMY dsRNA also impaired actin and Arp2 expression, and co-injection of actin and Arp2 mRNA partially rescued blastocyst development. Taken together, our results show that the NPF JMY is involved in the development of porcine embryos by regulating the NPF-Arp2-actin pathway. PMID:26052154

  14. Germ cells of the centipede Strigamia maritima are specified early in embryonic development.

    PubMed

    Green, Jack E; Akam, Michael

    2014-08-15

    We provide the first systematic description of germ cell development with molecular markers in a myriapod, the centipede Strigamia maritima. By examining the expression of Strigamia vasa and nanos orthologues, we find that the primordial germ cells are specified from at least the blastoderm stage. This is a much earlier embryonic stage than previously described for centipedes, or any other member of the Myriapoda. Using these genes as markers, and taking advantage of the developmental synchrony of Strigamia embryos within single clutches, we are able to track the development of the germ cells throughout embryogenesis. We find that the germ cells accumulate at the blastopore; that the cells do not internalize through the hindgut, but rather through the closing blastopore; and that the cells undergo a long-range migration to the embryonic gonad. This is the first evidence for primordial germ cells displaying these behaviours in any myriapod. The myriapods are a phylogenetically important group in the arthropod radiation for which relatively little developmental data is currently available. Our study provides valuable comparative data that complements the growing number of studies in insects, crustaceans and chelicerates, and is important for the correct reconstruction of ancestral states and a fuller understanding of how germ cell development has evolved in different arthropod lineages.

  15. A new embryonic pattern in parasitic wasps: divergence in early development may not be associated with lifestyle.

    PubMed

    Mancini, Donato; Garonna, Antonio P; Pedata, Paolo A

    2013-01-01

    Comparative embryogenesis of Encarsia formosa and Encarsia pergandiella (Hymenoptera Aphelinidae), two endoparasitoids of whiteflies (Hemiptera Aleyrodidae), revealed two strongly diverging developmental patterns. Indeed, the centrolecithal anhydropic egg of E. formosa developed through a superficial cleavage, as it occurs in Nasonia vitripennis, Apis mellifera, and Drosophila melanogaster. In contrast, the alecithal hydropic egg of E. pergandiella developed through holoblastic cleavage within a specialized extra-embryonic membrane (EEM). Since this developmental pattern evolved independently in several lineages of hymenopteran endoparasitoids, departures from the superficial cleavage mode have been argued to be strongly canalized in response to a shift from ecto- to endoparasitic lifestyle. Coexistence of both developmental patterns in two congeneric species suggests that alterations of early embryonic development may not be correlated with lifestyle. In addition, embryogenesis of E. pergandiella exhibited the following developmental novelties compared to other species possessing a hydropic egg: (i) polar body derivatives early acquired a cytoskeletal boundary prior to any other cellularization event; (ii) cellularization was asynchronous, starting with an early differentiation of a single apical blastomere at the end of the third cleavage; (iii) appearance of cytoskeletal boundaries of embryo blastomeres occurred between the third and fourth cleavages; (iv) the EEM originated through asynchronous participation of three separate lineages of cleavage nuclei, one of which associated with the polar body derivatives in a syncytium. Our results confirm a scenario of high plasticity in the early developmental strategies of hymenopteran endoparasitoids.

  16. Coxsackievirus-adenovirus receptor (CAR) is essential for early embryonic cardiac development.

    PubMed

    Dorner, Armin A; Wegmann, Frank; Butz, Stefan; Wolburg-Buchholz, Karen; Wolburg, Hartwig; Mack, Andreas; Nasdala, Ines; August, Benjamin; Westermann, Jürgen; Rathjen, Fritz G; Vestweber, Dietmar

    2005-08-01

    The coxsackievirus-adenovirus receptor (CAR) is a cell contact protein on various cell types with unknown physiological function. It belongs to a subfamily of the immunoglobulin-superfamily of which some members are junctional adhesion molecules on epithelial and/or endothelial cells. CAR is dominantly expressed in the hearts and brains of mice until the newborne phase after which it becomes mainly restricted to various epithelial cells. To understand more about the physiological function of CAR, we have generated CAR-deficient mice by gene targeting. We found that these mice die between E11.5 and E13.5 of embryonal development. Ultrastructural analysis of cardiomyocytes revealed that the density of myofibrils was reduced and that their orientation and bundling was disorganized. In addition, mitochondria were enlarged and glycogen storage strongly enriched. In line with these defects, we observed pericardial edema formation as a clear sign of insufficient heart function. Developmental abnormalities likely to be secondary effects of gene ablation were the persistent singular cardial atrio-ventricular canal and dilatations of larger blood vessels such as the cardinal veins. The secondary nature of these defects was supported by the fact that CAR was not expressed on vascular cells or on cells of the vascular wall. No obvious signs for alterations of the histological organization of the placenta were observed. We conclude that CAR is required for embryonal heart development, most likely due to its function during the organization of myofibrils in cardiomyocytes.

  17. Cell cycle control in the early embryonic development of aquatic animal species.

    PubMed

    Siefert, Joseph C; Clowdus, Emily A; Sansam, Christopher L

    2015-12-01

    The cell cycle is integrated with many aspects of embryonic development. Not only is proper control over the pace of cell proliferation important, but also the timing of cell cycle progression is coordinated with transcription, cell migration, and cell differentiation. Due to the ease with which the embryos of aquatic organisms can be observed and manipulated, they have been a popular choice for embryologists throughout history. In the cell cycle field, aquatic organisms have been extremely important because they have played a major role in the discovery and analysis of key regulators of the cell cycle. In particular, the frog Xenopus laevis has been instrumental for understanding how the basic embryonic cell cycle is regulated. More recently, the zebrafish has been used to understand how the cell cycle is remodeled during vertebrate development and how it is regulated during morphogenesis. This review describes how some of the unique strengths of aquatic species have been leveraged for cell cycle research and suggests how species such as Xenopus and zebrafish will continue to reveal the roles of the cell cycle in human biology and disease.

  18. Gravity and embryonic development

    NASA Technical Reports Server (NTRS)

    Young, R. S.

    1976-01-01

    The relationship between the developing embryo (both plant and animal) and a gravitational field has long been contemplated. The difficulty in designing critical experiments on the surface of the earth because of its background of 1 g, has been an obstacle to a resolution of the problem. Biological responses to gravity (particularly in plants) are obvious in many cases; however, the influence of gravity as an environmental input to the developing embryo is not as obvious and has proven to be extremely difficult to define. In spite of this, over the years numerous attempts have been made using a variety of embryonic materials to come to grips with the role of gravity in development. Three research tools are available: the centrifuge, the clinostat, and the orbiting spacecraft. Experimental results are now available from all three sources. Some tenuous conclusions are drawn, and an attempt at a unifying theory of gravitational influence on embryonic development is made.

  19. Gravity and embryonic development

    NASA Technical Reports Server (NTRS)

    Young, R. S.

    1976-01-01

    The relationship between the developing embryo (both plant and animal) and a gravitational field has long been contemplated. The difficulty in designing critical experiments on the surface of the earth because of its background of 1 g, has been an obstacle to a resolution of the problem. Biological responses to gravity (particularly in plants) are obvious in many cases; however, the influence of gravity as an environmental input to the developing embryo is not as obvious and has proven to be extremely difficult to define. In spite of this, over the years numerous attempts have been made using a variety of embryonic materials to come to grips with the role of gravity in development. Three research tools are available: the centrifuge, the clinostat, and the orbiting spacecraft. Experimental results are now available from all three sources. Some tenuous conclusions are drawn, and an attempt at a unifying theory of gravitational influence on embryonic development is made.

  20. Effects of gestational diethylstilbestrol treatment on male and female gonads during early embryonic development.

    PubMed

    Ikeda, Yayoi; Tanaka, Hideo; Esaki, Michiyo

    2008-08-01

    To study the effects of gestational exposure to estrogen on early gonadal differentiation, pregnant mice were treated by sc injection of diethylstilbestrol (DES) or vehicle from embryonic day (E) 8.5 to E14.5, and gonads at E11.5, E12.5, and E14.5 were examined. Quantitative real-time RT-PCR and in situ hybridization revealed that mRNA levels of steroidogenic factor 1 (SF-1), a key regulator of gonadal differentiation, and several male gonad-specific genes, including Müllerian-inhibiting substance (MIS), steroidogenic acute regulatory protein, cholesterol side-chain cleavage cytochrome P450, and Cerebellin 1 precursor protein, were significantly decreased in the DES-treated testis, compared with the control testis at E12.5 and/or E14.5. Immunohistochemistry demonstrated that the staining intensities for SF-1 and MIS in Sertoli cells were apparently reduced in the DES-treated testis, compared with those of the controls, at E12.5 and E14.5. Because MIS, steroidogenic acute regulatory protein, cholesterol side-chain cleavage cytochrome P450, and Cerebellin 1 precursor protein are activated under the regulation of SF-1, the down-regulation of these factors may be due to reduced SF-1 expression. Immunohistochemistry for laminin-1 demonstrated that ovigerous cords in the DES-treated ovary were smaller than those in controls at E14.5. Moreover, the number of 5-bromo-2'deoxyuridine-5-monophosphate-labeled cells in the DES-treated testis was significantly reduced at E12.5 and E14.5, compared with controls, and that in the DES-treated ovary remained higher than that in the control ovary at E14.5. The results suggest that exogenous estrogens can alter sex-specific genetic pathways governing early differentiation and cell proliferation of both male and female gonads.

  1. Embryonic development during chronic acceleration

    NASA Technical Reports Server (NTRS)

    Smith, A. H.; Abbott, U. K.

    1982-01-01

    Experiments carried out on chicken eggs indicate that the embryo is affected during very early development, especially over the first four days, and during hatching. In the first four days, the brain develops as well as the anlage for all other organs. In addition, the heart commences to function and the extraembryonic membranes that compartmentalize the egg contents form. The latter require an appreciable extension and folding of tissue which may be disrupted by the mechanical load. Observations of embryonic abnormalities that occur during chronic acceleration suggest an inhibition of development of the axial skeleton, which is rarely seen otherwise, a general retardation of embryonic growth, and circulatory problems. The final stages of development (after 18 days) involve the uptake of fluids, the transition to aerial respiration, and the reorientation of the embryo into a normal hatching position. At 4 G mortality is very high during this period, with a majority of embryos failing to reorient into the normal hatching position.

  2. Embryonic development during chronic acceleration

    NASA Technical Reports Server (NTRS)

    Smith, A. H.; Abbott, U. K.

    1982-01-01

    Experiments carried out on chicken eggs indicate that the embryo is affected during very early development, especially over the first four days, and during hatching. In the first four days, the brain develops as well as the anlage for all other organs. In addition, the heart commences to function and the extraembryonic membranes that compartmentalize the egg contents form. The latter require an appreciable extension and folding of tissue which may be disrupted by the mechanical load. Observations of embryonic abnormalities that occur during chronic acceleration suggest an inhibition of development of the axial skeleton, which is rarely seen otherwise, a general retardation of embryonic growth, and circulatory problems. The final stages of development (after 18 days) involve the uptake of fluids, the transition to aerial respiration, and the reorientation of the embryo into a normal hatching position. At 4 G mortality is very high during this period, with a majority of embryos failing to reorient into the normal hatching position.

  3. Fibroblast growth factor 13 is essential for neural differentiation in Xenopus early embryonic development.

    PubMed

    Nishimoto, Satoko; Nishida, Eisuke

    2007-08-17

    In Xenopus embryonic development, the MEK5-ERK5 pathway, one of the MAPK pathways, lies downstream of SoxD and upstream of Xngnr1 in a signaling pathway regulating neural differentiation. It remains unclear, however, how the MEK5-ERK5 pathway is regulated in Xenopus neural development. As SoxD is a transcription factor, we hypothesized that some growth factor should be induced by SoxD and activate the MEK5-ERK5 pathway. As the expression level of fibroblast growth factor 13 (FGF13) is increased by SoxD, we analyzed the function of FGF13 in neural development. Knockdown of FGF13 with antisense morpholino-oligonucleotides (MOs) results in the reduced head structure and inhibition of neural differentiation. FGF13 MOs inhibit the SoxD-induced expression of Xngnr1 and the Xngnr1-induced expression of NeuroD, suggesting that FGF13 is necessary both upstream and downstream of Xngnr1 in neural differentiation. In addition, FGF13 MOs inhibit the activation of the MEK5-ERK5 pathway by dominant-negative bone morphogenetic protein receptor, a mimicker of neural inducers, indicating that FGF13 is involved in the activation of the MEK5-ERK5 pathway. Together, these results identify a role of FGF13 in Xenopus neural differentiation.

  4. Reproductive Toxicity of Zishen Yutai Pill in Rats: The Fertility and Early Embryonic Development Study (Segment I)

    PubMed Central

    Zhou, Li; Huang, Qiuling; Wang, Rong; Zhou, Jie; Ma, Aicui; Chong, Liming; Wu, Yubing; Wang, Yong; Xu, Li; Chen, Ying; Jia, Yuling; Gui, Bo

    2016-01-01

    Purpose. This study was aimed to investigate the reproductive toxicity of Zishen Yutai Pill (ZYP) on fertility and early embryonic development in rats. Methods. SD rats were randomly divided into 5 groups: vehicle control group (distilled water, i.g.), positive control group (80 mg/kg of cyclophosphamide, i.p.), and three ZYP-treated groups (3, 6, and 12 g/kg/d, i.e., 12x, 24x, and 48x clinical doses, i.g.). The high dose was set as the maximum gavage dosage. Results. Cyclophosphamide showed diverse hazards, such as decreased weight of male reproductive organs and sperm density (P < 0.05). However, there were no obvious effects of ZYP on physical signs, animal behavior, and survival rate, as well as on weight and food intake during the premating and gestation periods. Importantly, there were no significant adverse effects of ZYP on indexes of copulation, fecundity and fertility indexes, weights and coefficients of male reproductive organs, epididymal sperm number and motility, estrous cycle, preimplantation loss rate, and implantation rate. Besides, the numbers of live and resorbed fetuses per litter were not significantly altered. Conclusions. ZYP had no reproductive toxicities on fertility and early embryonic development in rats at 48x equivalent clinical doses. PMID:28058057

  5. KCTD10 is involved in the cardiovascular system and Notch signaling during early embryonic development.

    PubMed

    Ren, Kaiqun; Yuan, Jing; Yang, Manjun; Gao, Xiang; Ding, Xiaofeng; Zhou, Jianlin; Hu, Xingwang; Cao, Jianguo; Deng, Xiyun; Xiang, Shuanglin; Zhang, Jian

    2014-01-01

    As a member of the polymerase delta-interacting protein 1 (PDIP1) gene family, potassium channel tetramerisation domain-containing 10 (KCTD10) interacts with proliferating cell nuclear antigen (PCNA) and polymerase δ, participates in DNA repair, DNA replication and cell-cycle control. In order to further investigate the physiological functions of KCTD10, we generated the KCTD10 knockout mice. The heterozygous KCTD10(+/-) mice were viable and fertile, while the homozygous KCTD10(-/-) mice showed delayed growth from E9.0, and died at approximately E10.5, which displayed severe defects in angiogenesis and heart development. Further study showed that VEGF induced the expression of KCTD10 in a time- and dose-dependent manner. Quantitative real-time PCR and western blotting results revealed that several key members in Notch signaling were up-regulated either in KCTD10-deficient embryos or in KCTD10-silenced HUVECs. Meanwhile, the endogenous immunoprecipitation (IP) analysis showed that KCTD10 interacted with Cullin3 and Notch1 simultaneously, by which mediating Notch1 proteolytic degradation. Our studies suggest that KCTD10 plays crucial roles in embryonic angiogenesis and heart development in mammalians by negatively regulating the Notch signaling pathway.

  6. Comparative transcriptome analysis reveals a regulatory network of microRNA-29b during mouse early embryonic development

    PubMed Central

    Wan, Jinyuan; Yang, Ye; Chen, Xiaojiao; Wang, Jiayi; Zhou, Cheng; Liu, Mingxi; Ling, Xiufeng; Zhang, Junqiang

    2016-01-01

    MicroRNAs are endogenous ~22 nt RNAs that regulate gene expression by translational inhibition and mRNA destabilization. MicroRNA-29b (miR-29b) is essential for progression of mouse embryos past preimplantation development; however, details of the underlying regulatory network remain to be elucidated. Here, we used RNA sequencing to identify changes in the transcriptome of mouse embryos in response to miR-29b inhibition. Morula-stage embryos that had been subject to miR-29b inhibition throughout preimplantation development exhibited significant expression changes in 870 genes compared with controls. Among 405 genes that were downregulated, 30 genes encoded factors with known essential function during early embryonic development, including the pluripotent stem cell factor Nanog. We identified 19 genes encoding putative miR-29b target transcripts. These included Zbtb40, Hbp1, Ccdc117, Ypel2, Klf4, and Tmed9, which are upregulated at the 4-cell state of mouse development concomitant with miR-29b downregulation. Luciferase reporter analysis confirmed that Zbtb40, Hbp1, Ccdc117, Ypel2, and Klf4 transcripts are direct targets of miR-29b. These results suggest that miR-29b decreases the mRNA levels of several target genes during early mouse development, including the gene encoding the reprogramming factor Klf4. We hypothesize that inhibition of miR-29b causes overexpression of its target genes, triggering downstream signaling networks to decrease the expression of genes that are essential for embryonic development. In conclusion, miR-29b controls an extensive regulatory network in early mouse embryos, which comprises reprogramming factors and molecular regulators of post-transcriptional modification processes. PMID:27449102

  7. Acid water interferes with salamander-green algae symbiosis during early embryonic development.

    PubMed

    Bianchini, Kristin; Tattersall, Glenn J; Sashaw, Jessica; Porteus, Cosima S; Wright, Patricia A

    2012-01-01

    The inner egg capsule of embryos of the yellow-spotted salamander (Ambystoma maculatum) are routinely colonized by green algae, such as Oophila amblystomatis, that supply O(2) in the presence of light and may consume nitrogenous wastes, forming what has been proposed to be a mutualistic relationship. Given that A. maculatum have been reported to breed in acidic (pH <5.0) and neutral lakes, we hypothesized that low water pH would negatively affect these symbiotic organisms and alter the gradients within the jelly mass. Oxygen gradients were detected within jelly masses measured directly in a natural breeding pond (pH 4.5-4.8) at midday in full sunlight. In the lab, embryo jelly masses reared continuously at pH 4.5 had lower P(O)₂and higher ammonia levels relative to jelly masses held at pH 8.0 (control). Ammonia and lactate concentrations in embryonic tissues were approximately 37%-93% higher, respectively, in embryos reared at water pH 4.5 compared with pH 8.0. Mass was also reduced in embryos reared at pH 4.5 versus pH 8.0. In addition, light conditions (24 h light, 12L : 12D, or 24 h dark) and embryonic position (periphery vs. center) in the jelly mass affected P(O)₂but not ammonia gradients, suggesting that algal symbionts generate O(2) but do not significantly impact local ammonia concentrations, regardless of the pH of the water. We conclude that chronic exposure to acidic breeding ponds had a profound effect on the microenvironment of developing A. maculatum embryos, which in turn resulted in an elevation of potentially harmful metabolic end products and inhibited growth. Under acidic conditions, the expected benefit provided by the algae to the salamander embryo (i.e., high O(2) and low ammonia microenvironment) is compromised, suggesting that the A. maculatum-algal mutualism is beneficial to salamanders only at higher water pH values.

  8. Bone morphogenetic protein 1 is expressed in porcine ovarian follicles and promotes oocyte maturation and early embryonic development

    PubMed Central

    LEI, Xiaocan; CUI, Kuiqing; CAI, Xiaoyan; REN, Yanping; LIU, Qingyou; SHI, Deshun

    2016-01-01

    In the present study, we tried to determine whether bone morphogenetic protein 1 (BMP1) plays a role in ovarian follicular development and early embryo development. We systematically investigated the expression and influence of BMP1 during porcine follicle and early embryonic development. Immunohistochemistry demonstrated that the BMP1 protein is expressed in granular cells and oocytes during follicular development, from primary to pre-ovulatory follicles, including atretic follicles and the corpus luteum. The mRNA expression of BMP1 significantly increased as the porcine follicles grew. Immunofluorescence analysis indicated that BMP1 was expressed in cumulus-oocyte complexes (COCs), oocytes and porcine embryos during early in vitro culture. qPCR and western blot analysis showed that the expression of BMP1 was significantly up-regulated in mature porcine oocytes and COCs compared to immature oocytes and COCs. BMP1 is expressed in early porcine embryos, and its expression reaches a peak at the 8-cell stage. To determine the effect of BMP1 on the maturation of oocytes and the development of early embryos, various concentrations of BMP1 recombinant protein or antibody were added to the in vitro culture media, respectively. BMP1 significantly affected the porcine oocyte maturation rate, the cleavage rate and the blastocyst development rate of embryos cultured in vitro in a positive way, as well as the blastocyst cell number. In conclusion, BMP1 is expressed throughout porcine ovarian follicle development and early embryogenesis, and it promotes oocyte maturation and the developmental ability of embryos during early in vitro culture. PMID:27890905

  9. Embryonic and early fetal period development and morphogenesis of human craniovertebral junction.

    PubMed

    Hita-Contreras, Fidel; Roda, Olga; Martínez-Amat, Antonio; Cruz-Díaz, David; Mérida-Velasco, Juan A; Sánchez-Montesinos, Indalecio

    2014-04-01

    Several studies have focused on the cartilaginous, articular, and ligamentous development of the craniovertebral joint (CVJ), but there are no unifying criteria regarding the origin and morphogenetic timetable of the structures that make up the CVJ. In our study, serial sections of 53 human embryonic (n = 27) and fetal (n = 26) specimens from O'Rahilly stages 17-23 and 9-13 weeks, respectively, have been analyzed. Our results demonstrate that the chondrification of the pars basioccipitalis and exoccipitalis becomes observable at stage 19, and all future bones in the CVJ are in their cartilaginous form except for the future odontoid process. In addition, two chondrification centers appear for the body of the axis. From stage 21, the apical, alar, and transverse atlantal ligaments begin to acquire a ligamentous structure and the odontoid process initiates its chondrogenic phase. Stage 22 witnesses the first signs of the articular cavities of the atlanto-occipital joint, and by stage 23 all joints have cavities except for the transverse-odontoid joint, which will wait until week 9. In week 10, the ossification of the basilar part of the occipital bone begins, followed by the rest of the structures except for the odontoid process, which will start at week 13, thus completing the osteogenesis of all bones in the CVJ. The results of this study could help in establishing the anatomical basis of the normally functioning CVJ and for detecting its related pathologies, abnormalities, and malformations.

  10. Student Learning of Early Embryonic Development via the Utilization of Research Resources from the Nematode Caenorhabditis elegans

    PubMed Central

    Eliceiri, Kevin W.; Squirrell, Jayne M.; White, John G.; Stewart, James

    2008-01-01

    This study was undertaken to gain insights into undergraduate students' understanding of early embryonic development, specifically, how well they comprehend the concepts of volume constancy, cell lineages, body plan axes, and temporal and spatial dimensionality in development. To study student learning, a curriculum was developed incorporating resources from the Caenorhabditis elegans research community. Students engaged in a preactivity assessment, followed by instructional materials (IMs) emphasizing inquiry-based learning and a postinstruction assessment to gauge their learning. This study, conducted at two research sites with eight and nine students, respectively, shows that before instruction, most students confused embryonic cell cleavage, where total volume is constant, with regular cell division, in which total cell volume doubles. Despite their ability to construct a cell lineage tree, most of the study participants were not aware of its biological significance. All students correctly identified cells of anterior and posterior axis, but not cells of the dorsal and ventral axis. Although the students had no difficulty with the time dimensional aspect of development, most viewed an embryo as spatially two-dimensional rather than three-dimensional. Furthermore, this study indicates that combining authentic research resources with inquiry-based learning benefits student learning of key concepts in embryology. PMID:18316809

  11. Early embryonic development of the central nervous system in the Australian crayfish and the Marbled crayfish (Marmorkrebs).

    PubMed

    Vilpoux, K; Sandeman, R; Harzsch, S

    2006-04-01

    This study sets out to provide a systematic analysis of the development of the primordial central nervous system (CNS) in embryos of two decapod crustaceans, the Australian crayfish Cherax destructor (Malacostraca, Decapoda, Astacida) and the parthenogenetic Marbled crayfish (Marmorkrebs, Malacostraca, Decapoda, Astacida) by histochemical labelling with phalloidin, a general marker for actin. One goal of our study was to examine the neurogenesis in these two organisms with a higher temporal resolution than previous studies did. The second goal was to explore if there are any developmental differences between the parthenogenetic Marmorkrebs and the sexually reproducing Australian crayfish. We found that in the embryos of both species the sequence of neurogenetic events and the architecture of the embryonic CNS are identical. The naupliar neuromeres proto-, deuto-, tritocerebrum, and the mandibular neuromeres emerge simultaneously. After this "naupliar brain" has formed, there is a certain time lag before the maxilla one primordium develops and before the more caudal neuromeres follow sequentially in the characteristic anterior-posterior gradient. Because the malacostracan egg-nauplius represents a re-capitulation of a conserved ancestral information, which is expressed during development, we speculate that the naupliar brain also conserves an ancestral piece of information on how the brain architecture of an early crustacean or even arthropod ancestor may have looked like. Furthermore, we compare the architecture of the embryonic crayfish CNS to that of the brain and thoracic neuromeres in insects and discuss the similarities and differences that we found against an evolutionary background.

  12. Expression of Immune-Related Genes during Loach (Misgurnus anguillicaudatus) Embryonic and Early Larval Development

    PubMed Central

    Lee, Jang Wook; Kim, Jung Eun; Goo, In Bon; Hwang, Ju-Ae; Im, Jea Hyun; Choi, Hye-Sung; Lee, Jeong-Ho

    2015-01-01

    Early life stage mortality in fish is one of the problems faced by loach aquaculture. However, our understanding of immune system in early life stage fish is still incomplete, and the information available is restricted to a few fish species. In the present work, we investigated the expression of immune-related transcripts in loach during early development. In fishes, recombination-activating gene 1 (RAG-1) and sacsin (SACS) have been considered as immunological function. In this study, the expression of the both genes was assessed throughout the early developmental stages of loach using real-time PCR method. maRAG-1 mRNA was first detected in 0 dph, observed the increased mostly until 40 dph. Significant expression of maRAG-1 was detected in 0 to 40 dph. These patterns of expression may suggest that the loach start to develop its function after hatching. On the other hand, maSACS was detected in unfertilized oocyte to molura stages and 0 to 40 dph. maSACS mRNA transcripts were detected in unfertilized oocytes, suggesting that they are maternally transferred. PMID:26973969

  13. The potential role of As-sumo-1 in the embryonic diapause process and early embryo development of Artemia sinica.

    PubMed

    Chu, Bing; Yao, Feng; Cheng, Cheng; Wu, Yang; Mei, Yanli; Li, Xuejie; Liu, Yan; Wang, Peisheng; Hou, Lin; Zou, Xiangyang

    2014-01-01

    During embryonic development of Artemia sinica, environmental stresses induce the embryo diapause phenomenon, required to resist apoptosis and regulate cell cycle activity. The small ubiquitin-related modifier-1 (SUMO), a reversible post-translational protein modifier, plays an important role in embryo development. SUMO regulates multiple cellular processes, including development and other biological processes. The molecular mechanism of diapause, diapause termination and the role of As-sumo-1 in this processes and in early embryo development of Artemia sinica still remains unknown. In this study, the complete cDNA sequences of the sumo-1 homolog, sumo ligase homolog, caspase-1 homolog and cyclin B homolog from Artemia sinica were cloned. The mRNA expression patterns of As-sumo-1, sumo ligase, caspase-1, cyclin B and the location of As-sumo-1 were investigated. SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E proteins were analyzed during different developmental stages of the embryo of A. sinica. Small interfering RNA (siRNA) was used to verify the function of sumo-1 in A. sinica. The full-length cDNA of As-sumo-1 was 476 bp, encoding a 92 amino acid protein. The As-caspases-1 cDNA was 966 bp, encoding a 245 amino-acid protein. The As-sumo ligase cDNA was 1556 bp encoding, a 343 amino acid protein, and the cyclin B cDNA was 739 bp, encoding a 133 amino acid protein. The expressions of As-sumo-1, As-caspase-1 and As-cyclin B were highest at the 10 h stage of embryonic development, and As-sumo ligase showed its highest expression at 0 h. The expression of As-SUMO-1 showed no tissue or organ specificity. Western blotting showed high expression of As-SUMO-1, p53, Mdm2, Caspase-1, Cyclin B and Cyclin E at the 10 h stage. The siRNA caused abnormal development of the embryo, with increased malformation and mortality. As-SUMO-1 is a crucial regulation and modification protein resumption of embryonic diapause and early embryo development of A. sinica.

  14. Expression Pattern of Early Growth Response Gene 1 during Olive Flounder (Paralichthys olivaceus) Embryonic Development

    PubMed Central

    Yang, Hyun; Lee, Jeong-Ho; Noh, Jae Koo; Kim, Hyun Chul; Park, Choul-Ji; Park, Jong-Won; Kim, Kyung-Kil

    2014-01-01

    The early growth response protein 1 (Egr-1) is a widely reported zinc finger protein and a well known transcription factor encoded by the Egr-1 gene, which plays key roles in many aspects of vertebrate embryogenesis and in adult vertebrates. The Egr-1 expression is important in the formation of the gill vascular system in flounders, which develops during the post-hatching phase and is essential for survival during the juvenile period. However, the complete details of Egr-1 expression during embryo development in olive flounder are not available. We assessed the expression patterns of Egr-1 during the early development of olive flounders by using reverse transcription polymerase chain reaction (RT-PCR) analysis. Microscopic observations showed that gill filament formation corresponded with the Egr-1 expression. Thus, we showed that Egr-1 plays a vital role in angiogenesis in the gill filaments during embryogenesis. Further, Egr-1 expression was found to be strong at 5 days after hatching (DAH), in the development of the gill vascular system, and this strong expression level was maintained throughout all the development stages. Our findings have important implications with respect to the biological role of Egr-1 and evolution of the first respiratory blood vessels in the gills of olive flounder. Further studies are required to elucidate the Egr-1-mediated stress response and to decipher the functional role of Egr-1 in developmental stages. PMID:25949193

  15. Nitric oxide synthase during early embryonic development in silkworm Bombyx mori: Gene expression, enzyme activity, and tissue distribution.

    PubMed

    Kitta, Ryo; Kuwamoto, Marina; Yamahama, Yumi; Mase, Keisuke; Sawada, Hiroshi

    2016-12-01

    To elucidate the mechanism for embryonic diapause or the breakdown of diapause in Bombyx mori, we biochemically analyzed nitric oxide synthase (NOS) during the embryogenesis of B. mori. The gene expression and enzyme activity of B. mori NOS (BmNOS) were examined in diapause, non-diapause, and HCl-treated diapause eggs. In the case of HCl-treated diapause eggs, the gene expression and enzyme activity of BmNOS were induced by HCl treatment. However, in the case of diapause and non-diapause eggs during embryogenesis, changes in the BmNOS activity and gene expressions did not coincide except 48-60 h after oviposition in diapause eggs. The results imply that changes in BmNOS activity during the embryogenesis of diapause and non-diapause eggs are regulated not only at the level of transcription but also post-transcription. The distribution and localization of BmNOS were also investigated with an immunohistochemical technique using antibodies against the universal NOS; the localization of BmNOS was observed mainly in the cytoplasm of yolk cells in diapause eggs and HCl-treated diapause eggs. These data suggest that BmNOS has an important role in the early embryonic development of the B. mori.

  16. Tyrosine pathway regulation is host-mediated in the pea aphid symbiosis during late embryonic and early larval development

    PubMed Central

    2013-01-01

    Background Nutritional symbioses play a central role in insects’ adaptation to specialized diets and in their evolutionary success. The obligatory symbiosis between the pea aphid, Acyrthosiphon pisum, and the bacterium, Buchnera aphidicola, is no exception as it enables this important agricultural pest insect to develop on a diet exclusively based on plant phloem sap. The symbiotic bacteria provide the host with essential amino acids lacking in its diet but necessary for the rapid embryonic growth seen in the parthenogenetic viviparous reproduction of aphids. The aphid furnishes, in exchange, non-essential amino acids and other important metabolites. Understanding the regulations acting on this integrated metabolic system during the development of this insect is essential in elucidating aphid biology. Results We used a microarray-based approach to analyse gene expression in the late embryonic and the early larval stages of the pea aphid, characterizing, for the first time, the transcriptional profiles in these developmental phases. Our analyses allowed us to identify key genes in the phenylalanine, tyrosine and dopamine pathways and we identified ACYPI004243, one of the four genes encoding for the aspartate transaminase (E.C. 2.6.1.1), as specifically regulated during development. Indeed, the tyrosine biosynthetic pathway is crucial for the symbiotic metabolism as it is shared between the two partners, all the precursors being produced by B. aphidicola. Our microarray data are supported by HPLC amino acid analyses demonstrating an accumulation of tyrosine at the same developmental stages, with an up-regulation of the tyrosine biosynthetic genes. Tyrosine is also essential for the synthesis of cuticular proteins and it is an important precursor for cuticle maturation: together with the up-regulation of tyrosine biosynthesis, we observed an up-regulation of cuticular genes expression. We were also able to identify some amino acid transporter genes which are

  17. CHD1 Regulates Deposition of Histone Variant H3.3 During Bovine Early Embryonic Development.

    PubMed

    Zhang, Kun; Rajput, Sandeep K; Wang, Shaohua; Folger, Joseph K; Knott, Jason G; Smith, George W

    2016-06-01

    The CHD family of proteins is characterized by the presence of chromodomains and SNF2-related helicase/ATPase domains, which alter gene expression by modification of chromatin structure. Chd1-null embryos arrest at the peri-implantation stage in mice. However, the functional role of CHD1 during preimplantation development remains unclear, given maternal-derived CHD1 may mask the essential role of CHD1 during this stage in traditional knockout models. The objective of this study was to characterize CHD1 expression and elucidate its functional role in preimplantation development using the bovine model. CHD1 mRNA was elevated after meiotic maturation and remained increased through the 16-cell stage, followed by a sharp decrease at morula to blastocyst stage. Similarly, immunoblot analysis indicated CHD1 protein level is increased after maturation, maintained at high level after fertilization and declined sharply afterwards. CHD1 mRNA level was partially decreased in response to alpha-amanitin (RNA polymerase II inhibitor) treatment, suggesting that CHD1 mRNA in eight-cell embryos is of both maternal and zygotic origin. Results of siRNA-mediated silencing of CHD1 in bovine early embryos demonstrated that the percentages of embryos developing to the 8- to 16-cell and blastocyst stages were both significantly reduced. However, expression of NANOG (inner cell mass marker) and CDX2 (trophectoderm marker) were not affected in CHD1 knockdown blastocysts. In addition, we found that histone variant H3.3 immunostaining is altered in CHD1 knockdown embryos. Knockdown of H3.3 using siRNA resulted in a similar phenotype to CHD1-ablated embryos. Collectively, our results demonstrate that CHD1 is required for bovine early development, and suggest that CHD1 may regulate H3.3 deposition during this period.

  18. Uterine crowding in the sow affects litter sex ratio, placental development and embryonic myogenin expression in early gestation.

    PubMed

    Tse, W-Y; Town, S C; Murdoch, G K; Novak, S; Dyck, M K; Putman, C T; Foxcroft, G R; Dixon, W T

    2008-01-01

    Uterine crowding in the pig results in intrauterine growth restriction (IUGR), and permanently affects fetal muscle fibre development, representing production losses for the commercial pig herd. The present study sought to understand how different levels of uterine crowding in sows affects muscle fibre development in the early embryo at the time of muscle fibre differentiation and proliferation. Sows either underwent surgical, unilateral oviduct ligation (LIG; n = 10) to reduce the number of embryos in the uterus, or remained as intact, relatively-crowded controls (CTR; n = 10). Embryos and placentae were collected at Day 30 of gestation, and myogenic regulatory factor (MRF) transcript abundance was determined using real-time PCR for both myogenin (MYOG) and myoblast differentiation 1 (MYOD1). Unilateral tubal ligation resulted in lower numbers of embryos in utero, higher placental weights and a higher male : female sex ratio (P < 0.05). Relative MYOD1 expression was not different, but MYOG expression was higher (P < 0.05) in the LIG group embryos; predominantly due to effects on the male embryos. Relatively modest uterine crowding therefore affects MRF expression, even at very early stages of embryonic development, and could contribute to reported differences in fetal muscle fibre development, birthweight and thus post-natal growth performance in swine.

  19. Influence of mefloquine administration during early pregnancy on rat embryonic development.

    PubMed

    El-Dakdoky, Mai Helmy

    2015-02-01

    Mefloquine (MQ) is a potent effective antimalarial drug against multiple drug-resistant Plasmodium falciparum. It has been proved that MQ can be given safely during the second and third trimesters. However, there is very limited information on the drug safety during the first trimester. The aim of the present work was to investigate the embryotoxicity and teratogenicity of MQ during critical periods of early development. Wistar rats were orally administered with a single dose of MQ (45 mg/kg bwt or 187 mg/kg bwt) on the 1st, 6th or 13th days of pregnancy. Cyclophosphamide (CPA) was chosen as a positive control. On the 21st day of gestation, standard parameters of reproductive performance and fetal examination were estimated. Malondialdehyde (MDA) level, glutathione reductase activity and glutathione (GSH) content were evaluated in placenta and liver homogenates of mothers and fetuses. The results indicated that MQ did not adversely affect the number of implantation, resorption, litter size and fetal body weight and length. Only groups treated with MQ on the 1st day of gestation exhibited significant decrease in fetal body weight. Examination of fetuses for external, visceral and skeletal changes showed minimal variations involving extension of lateral brain ventricles and renal pelvis and signs of delayed ossification. These variations were accompanied with significant elevation of MDA level and reduction of GSH content of fetal liver. Prenatal exposure to MQ at early pregnancy did not cause any embryolethal or teratogenic effect. It could slightly exacerbate minor variations.

  20. FGF/EGF signaling regulates the renewal of early nephron progenitors during embryonic development.

    PubMed

    Brown, Aaron C; Adams, Derek; de Caestecker, Mark; Yang, Xuehui; Friesel, Robert; Oxburgh, Leif

    2011-12-01

    Recent studies indicate that nephron progenitor cells of the embryonic kidney are arranged in a series of compartments of an increasing state of differentiation. The earliest progenitor compartment, distinguished by expression of CITED1, possesses greater capacity for renewal and differentiation than later compartments. Signaling events governing progression of nephron progenitor cells through stages of increasing differentiation are poorly understood, and their elucidation will provide key insights into normal and dysregulated nephrogenesis, as well as into regenerative processes that follow kidney injury. In this study, we found that the mouse CITED1(+) progenitor compartment is maintained in response to receptor tyrosine kinase (RTK) ligands that activate both FGF and EGF receptors. This RTK signaling function is dependent on RAS and PI3K signaling but not ERK. In vivo, RAS inactivation by expression of sprouty 1 (Spry1) in CITED1(+) nephron progenitors results in loss of characteristic molecular marker expression and in increased death of progenitor cells. Lineage tracing shows that surviving Spry1-expressing progenitor cells are impaired in their subsequent epithelial differentiation, infrequently contributing to epithelial structures. These findings demonstrate that the survival and developmental potential of cells in the earliest embryonic nephron progenitor cell compartment are dependent on FGF/EGF signaling through RAS.

  1. Early embryonic brain development in rats requires the trophic influence of cerebrospinal fluid.

    PubMed

    Martin, C; Alonso, M I; Santiago, C; Moro, J A; De la Mano, A; Carretero, R; Gato, A

    2009-11-01

    Cerebrospinal fluid has shown itself to be an essential brain component during development. This is particularly evident at the earliest stages of development where a lot of research, performed mainly in chick embryos, supports the evidence that cerebrospinal fluid is involved in different mechanisms controlling brain growth and morphogenesis, by exerting a trophic effect on neuroepithelial precursor cells (NPC) involved in controlling the behaviour of these cells. Despite it being known that cerebrospinal fluid in mammals is directly involved in corticogenesis at fetal stages, the influence of cerebrospinal fluid on the activity of NPC at the earliest stages of brain development has not been demonstrated. Here, using "in vitro" organotypic cultures of rat embryo brain neuroepithelium in order to expose NPC to or deprive them of cerebrospinal fluid, we show that the neuroepithelium needs the trophic influence of cerebrospinal fluid to undergo normal rates of cell survival, replication and neurogenesis, suggesting that NPC are not self-sufficient to induce their normal activity. This data shows that cerebrospinal fluid is an essential component in chick and rat early brain development, suggesting that its influence could be constant in higher vertebrates.

  2. Stereotypical physiological properties emerge during early neuronal and glial lineage development in the embryonic rat neocortex.

    PubMed

    Maric, D; Maric, I; Chang, Y H; Barker, J L

    2000-08-01

    Surface immunolabeling was used together with membrane potential and/or Ca(2+) indicator dyes to characterize physiological properties emerging among precursors, neuroglial progenitors and differentiating neurons during neurogenesis of embryonic rat neocortex. Cells were immunoidentified with tetanus toxin (TnTx), which binds to gangliosides expressed by neurons, and anti-A2B5, which reacts with gangliosides expressed by neuroglial progenitors. Microdissection of the neocortex into ventricular/subventricular zone (VZ/SVZ) and cortical plate/subplate (CP/SP) regions further resolved the TnTx/A2B5-immunoidentified cells into pre- and post-migratory subpopulations. Quantitative immunocytochemistry revealed mainly proliferative (BrdU(+)) and immature (nestin(+)) elements among TnTx(-)A2B5(-) precursors and TnTx(-)A2B5(+) progenitors in the VZ/SVZ, and the appearance of neuron-specific antigens among post-mitotic TnTx(+) subpopulations of the CP/SP. Flow cytometry of acutely prepared cells in suspension and dual-imaging of cells in culture revealed that ionotropic amino acid receptors and metabotropic acetylcholine receptors closely paralleled the emergence of voltage-dependent Na(+) and Ca(2+) channels and Na(+)-Ca(2+) exchange activity among TnTx(+) neuronal progenitors migrating from VZ/SVZ to CP/SP. During this period, TnTx(-)A2B5(-) precursors and TnTx(-)A2B5(+) neuroglial progenitors from VZ/SVZ predominantly exhibited Ca(2+) responses to ATP. Thus, stereotypical and contrasting physiologies emerge among embryonic cortical cells in vivo as they initially progress from proliferating precursors and progenitors along neuronal and glial cell lineages.

  3. Energetic Effects of Pre-hatch Albumen Removal on Embryonic Development and Early Ontogeny in Gallus gallus.

    PubMed

    Peña-Villalobos, Isaac; Piriz, Gabriela; Palma, Verónica; Sabat, Pablo

    2016-01-01

    Studies on the yolk and albumen content in bird eggs, and the effects of variations in their relative loads in the phenotype of the birds, have revealed multiple consequences at different levels of biological organization, from biochemical traits to behavior. However, little is known about the effect of albumen variation on energetics performance during development and early ontogeny, despite the fact that variation in energy expenditure may have consequences in terms of fitness for both feral and domestic species. In this work, we evaluated experimentally whether variations in the content of albumen of Gallus gallus eggs could generate differences in metabolic rates during embryonic development. Additionally, we assessed changes in the activity of mitochondrial enzymes (cytochrome c oxidase and citrate synthase) in skeletal muscles and liver. Finally, we evaluated the success of hatching of these embryos and their metabolic rates (MR) post-hatching. The results revealed a significant reduction in MR in the last fifth of embryonic life, and reduced catabolic activities in the skeletal muscle of chicks hatched from albumen-removed eggs. However, the same group demonstrated an increase in catabolic activity in the liver, suggesting the existence of changes in energy allocation between tissues. Besides, we found a decrease in hatching success in the albumen-removed group, suggesting a negative effect of the lower albumen content on eggs, possibly due to lower catabolic activities in skeletal muscle. We also found a compensatory phenomenon in the first week after hatching, i.e., birds from albumen-removed eggs did not show a decrease in MR either at thermoneutral temperatures or at 10°C, compared to the control group. Collectively, our data suggest that a reduction in albumen may generate a trade-off between tissue metabolic activities, and may explain the differences in metabolic rates and hatching success, supporting the immediate adaptive response (IAR) hypothesis.

  4. Energetic Effects of Pre-hatch Albumen Removal on Embryonic Development and Early Ontogeny in Gallus gallus

    PubMed Central

    Peña-Villalobos, Isaac; Piriz, Gabriela; Palma, Verónica; Sabat, Pablo

    2017-01-01

    Studies on the yolk and albumen content in bird eggs, and the effects of variations in their relative loads in the phenotype of the birds, have revealed multiple consequences at different levels of biological organization, from biochemical traits to behavior. However, little is known about the effect of albumen variation on energetics performance during development and early ontogeny, despite the fact that variation in energy expenditure may have consequences in terms of fitness for both feral and domestic species. In this work, we evaluated experimentally whether variations in the content of albumen of Gallus gallus eggs could generate differences in metabolic rates during embryonic development. Additionally, we assessed changes in the activity of mitochondrial enzymes (cytochrome c oxidase and citrate synthase) in skeletal muscles and liver. Finally, we evaluated the success of hatching of these embryos and their metabolic rates (MR) post-hatching. The results revealed a significant reduction in MR in the last fifth of embryonic life, and reduced catabolic activities in the skeletal muscle of chicks hatched from albumen-removed eggs. However, the same group demonstrated an increase in catabolic activity in the liver, suggesting the existence of changes in energy allocation between tissues. Besides, we found a decrease in hatching success in the albumen-removed group, suggesting a negative effect of the lower albumen content on eggs, possibly due to lower catabolic activities in skeletal muscle. We also found a compensatory phenomenon in the first week after hatching, i.e., birds from albumen-removed eggs did not show a decrease in MR either at thermoneutral temperatures or at 10°C, compared to the control group. Collectively, our data suggest that a reduction in albumen may generate a trade-off between tissue metabolic activities, and may explain the differences in metabolic rates and hatching success, supporting the immediate adaptive response (IAR) hypothesis

  5. Histology Atlas of the Developing Mouse Hepatobiliary Hemolymphatic Vascular System with Emphasis on Embryonic Days 11.5-18.5 and Early Postnatal Development.

    PubMed

    Swartley, Olivia M; Foley, Julie F; Livingston, David P; Cullen, John M; Elmore, Susan A

    2016-07-01

    A critical event in embryo development is the proper formation of the vascular system, of which the hepatobiliary system plays a pivotal role. This has led researchers to use transgenic mice to identify the critical steps involved in developmental disorders associated with the hepatobiliary vascular system. Vascular development is dependent upon normal vasculogenesis, angiogenesis, and the transformation of vessels into their adult counterparts. Any alteration in vascular development has the potential to cause deformities or embryonic death. Numerous publications describe specific stages of vascular development relating to various organs, but a single resource detailing the stage-by-stage development of the vasculature pertaining to the hepatobiliary system has not been available. This comprehensive histology atlas provides hematoxylin & eosin and immunohistochemical-stained sections of the developing mouse blood and lymphatic vasculature with emphasis on the hepatobiliary system between embryonic days (E) 11.5-18.5 and the early postnatal period. Additionally, this atlas includes a 3-dimensional video representation of the E18.5 mouse venous vasculature. One of the most noteworthy findings of this atlas is the identification of the portal sinus within the mouse, which has been erroneously misinterpreted as the ductus venosus in previous publications. Although the primary purpose of this atlas is to identify normal hepatobiliary vascular development, potential embryonic abnormalities are also described. © The Author(s) 2016.

  6. Nuclear translocation of phospholipase C-zeta, an egg-activating factor, during early embryonic development

    SciTech Connect

    Sone, Yoshie; Ito, Masahiko; Shirakawa, Hideki; Shikano, Tomohide; Takeuchi, Hiroyuki; Kinoshita, Katsuyuki; Miyazaki, Shunichi . E-mail: shunm@research.twmu.ac.jp

    2005-05-13

    Phospholipase C-zeta (PLC{zeta}), a strong candidate of the egg-activating sperm factor, causes intracellular Ca{sup 2+} oscillations and egg activation, and is subsequently accumulated into the pronucleus (PN), when expressed in mouse eggs by injection of RNA encoding PLC{zeta}. Changes in the localization of expressed PLC{zeta} were investigated by tagging with a fluorescent protein. PLC{zeta} began to translocate into the PN formed at 5-6 h after RNA injection and increased there. Observation in the same embryo revealed that PLC{zeta} in the PN dispersed to the cytoplasm upon nuclear envelope breakdown and translocated again into the nucleus after cleavage. The dynamics was found in the second mitosis as well. When RNA was injected into fertilization-originated 1-cell embryos or blastomere(s) of 2-8-cell embryos, the nuclear localization of expressed PLC{zeta} was recognized in every embryo up to blastocyst. Thus, PLC{zeta} exhibited alternative cytoplasm/nucleus localization during development. This supports the view that the sperm factor could control cell cycle-dependent generation of Ca{sup 2+} oscillations in early embryogenesis.

  7. Effect of Carbonate Chemistry Alteration on the Early Embryonic Development of the Pacific Oyster (Crassostrea gigas)

    PubMed Central

    Gazeau, Frédéric; Gattuso, Jean-Pierre; Greaves, Mervyn; Elderfield, Henry; Peene, Jan; Heip, Carlo H. R.; Middelburg, Jack J.

    2011-01-01

    Ocean acidification, due to anthropogenic CO2 absorption by the ocean, may have profound impacts on marine biota. Calcareous organisms are expected to be particularly sensitive due to the decreasing availability of carbonate ions driven by decreasing pH levels. Recently, some studies focused on the early life stages of mollusks that are supposedly more sensitive to environmental disturbances than adult stages. Although these studies have shown decreased growth rates and increased proportions of abnormal development under low pH conditions, they did not allow attribution to pH induced changes in physiology or changes due to a decrease in aragonite saturation state. This study aims to assess the impact of several carbonate-system perturbations on the growth of Pacific oyster (Crassostrea gigas) larvae during the first 3 days of development (until shelled D-veliger larvae). Seawater with five different chemistries was obtained by separately manipulating pH, total alkalinity and aragonite saturation state (calcium addition). Results showed that the developmental success and growth rates were not directly affected by changes in pH or aragonite saturation state but were highly correlated with the availability of carbonate ions. In contrast to previous studies, both developmental success into viable D-shaped larvae and growth rates were not significantly altered as long as carbonate ion concentrations were above aragonite saturation levels, but they strongly decreased below saturation levels. These results suggest that the mechanisms used by these organisms to regulate calcification rates are not efficient enough to compensate for the low availability of carbonate ions under corrosive conditions. PMID:21860666

  8. Ovulation, Fertilization and Early Embryonic Development in the Menstruating Fruit Bat, Carollia perspicillata

    PubMed Central

    Rasweiler IV, John J.; Badwaik, Nilima K.; Mechineni, Kiranmayi V.

    2010-01-01

    To characterize periovulatory events, reproductive tracts were collected at 12 hr intervals from captive-bred, short-tailed fruit bats, Carollia perspicillata, on days 1-3 post coitum and examined histologically. Most bats bred readily. Graafian follicles developed large antra and exhibited preovulatory expansion of the cumulus oophorus. Ovulation had occurred in some on the morning, and in most by the evening, of day 1. The single ovum was released as a secondary oocyte and fertilized in the oviductal ampulla. Ovulated secondary oocytes were loosely associated with their cumulus cells, which were lost around the initiation of fertilization. Supernumerary spermatozoa were occasionally noted attached to the zonae pellucidae of oviductal ova, but never within the perivitelline space. By day 2, most ova had reached the pronuclear stage and by day 3, early cleavage stages. Several lines of evidence indicate that C. perspicillata is a spontaneous ovulator with a functional luteal phase. Most newly-mated females had recently-formed, but regressing corpora lutea, and thickened (albeit menstrual) uteri despite having been housed with males only for brief periods (< 23 days). Menstruation is usually periovulatory in this species. Furthermore, the interval between successive estrus periods in most mated females that failed to establish ongoing pregnancies at the first was 21 – 27 days. Menstruation involved substantial endometrial desquamation, plus associated bleeding, and generally extended to the evening of day 3, the last time point studied. In nearly all females with a recent corpus luteum (n=24/25; 96%), the preovulatory or newly-ruptured follicle was in the opposite ovary. PMID:21337714

  9. Embryonic Development and Rates of Metabolic Activity in Early and Late Hatching Eggs of the Major Malaria Vector Anopheles gambiae

    PubMed Central

    Kaiser, Maria L.; Duncan, Frances D.; Brooke, Basil D.

    2014-01-01

    Anopheles gambiae eggs generally hatch at the completion of embryo development; two-three days post oviposition. However, staggered or delayed hatching has been observed whereby a single batch of eggs shows marked variation in time-to-hatch, with some eggs hatching 18 days post oviposition or later. The mechanism enabling delayed hatch has not been clearly elucidated but is likely mediated by environmental and genetic factors that either induce diapause or slow embryo development. This study aimed to compare metabolic activity and embryonic development between eggs collected from sub-colonies of the baseline Anopheles gambiae GAH colony previously selected for early or late time-to-hatch. Egg batches from early and late hatch sub-colonies as well as from the baseline colony were monitored for hatching. For both time-to-hatch selected sub-colonies and the baseline colony the majority of eggs hatched on day two post oviposition. Nevertheless, eggs produced by the late hatch sub-colony showed a significantly longer mean time to hatch than those produced by the early hatch sub-colony. The overall proportions that hatched were similar for all egg batches. CO2 output between eggs from early and late hatch sub-colonies showed significant differences only at 3 and 7 days post oviposition where eggs from the early hatch and the late hatch sub-colony were more metabolically active, respectively. No qualitative differences were observed in embryo development between the sub-colonies. It is concluded that all viable embryos develop to maturity at the same rate and that a small proportion then enter a state of diapause enabling them to hatch later. As it has previously been shown that it is possible to at least partially select for late hatch, this characteristic is likely to involve genetic as well as environmental factors. Delayed hatching in An. gambiae is likely an adaptation to maximise reproductive output despite the increased risk of desiccation in an unstable aquatic

  10. Sept6 is required for ciliogenesis in Kupffer's vesicle, the pronephros, and the neural tube during early embryonic development.

    PubMed

    Zhai, Gang; Gu, Qilin; He, Jiangyan; Lou, Qiyong; Chen, Xiaowen; Jin, Xia; Bi, Erfei; Yin, Zhan

    2014-04-01

    Septins are conserved filament-forming GTP-binding proteins that act as cellular scaffolds or diffusion barriers in a number of cellular processes. However, the role of septins in vertebrate development remains relatively obscure. Here, we show that zebrafish septin 6 (sept6) is first expressed in the notochord and then in nearly all of the ciliary organs, including Kupffer's vesicle (KV), the pronephros, eye, olfactory bulb, and neural tube. Knockdown of sept6 in zebrafish embryos results in reduced numbers and length of cilia in KV. Consequently, cilium-related functions, such as the left-right patterning of internal organs and nodal/spaw signaling, are compromised. Knockdown of sept6 also results in aberrant cilium formation in the pronephros and neural tube, leading to cilium-related defects in pronephros development and Sonic hedgehog (Shh) signaling. We further demonstrate that SEPT6 associates with acetylated α-tubulin in vivo and localizes along the axoneme in the cilia of zebrafish pronephric duct cells as well as cultured ZF4 cells. Our study reveals a novel role of sept6 in ciliogenesis during early embryonic development in zebrafish.

  11. Influence of estrus at fixed-time artificial insemination on early embryonic development in beef cattle.

    PubMed

    Larimore, E L; Amundson, O L; Bird, S L; Funnell, B J; Kruse, S G; Bridges, G A; Perry, G A

    2015-06-01

    It has been repeatedly demonstrated that estrous expression before fixed-time AI (TAI) results in increased pregnancy success. Therefore, the objective of this experiment was to determine if preblastocyst embryonic developmental characteristics differed from heifers that did or did not exhibit estrus before TAI. Beef heifers (n = 113) were synchronized using the 5-d CO-Synch + controlled internal drug release device with TAI on d 0. Before TAI, estrous expression was assessed twice daily. On d 6, single embryos were collected and visually evaluated to determine quality (International Embryo Transfer Society standards; 1-4, in which 1 = excellent/good and 4 = degenerate) and stage (1-9, in which 1 = unfertilized and 9 = expanded hatched blastocyst). Embryos were stained and evaluated to determine number of dead blastomeres, number of total blastomeres, and number of accessory sperm. Estrous expression before TAI did not affect the percent of embryos recovered (P = 0.59), number of dead cells (P = 0.99), or number of total cells (P = 0.25). However, heifers that exhibited estrus had increased mean (P = 0.03) and median accessory sperm numbers and (P = 0.01) percent live cells when compared with nonestrus heifers. Heifers that exhibited estrus also produced embryos that had a more advanced stage (P = 0.03) and improved quality (P = 0.04) when compared with those heifers not exhibiting estrus. When all heifers were evaluated, there was no correlation between circulating concentration of estradiol at TAI and embryo quality or embryo stage. There was a significant correlation between accessory sperm numbers and embryo quality (P = 0.01) and embryo stage (P < 0.01), such that as accessory sperm numbers increased, embryo quality and stage increased. In conclusion, exhibiting estrus before TAI resulted in improved embryo quality and advanced embryo stage on d 6 and increased the number of accessory sperm associated with the embryo.

  12. Effect of culture medium volume and embryo density on early mouse embryonic development: tracking the development of the individual embryo.

    PubMed

    Dai, Shan-Jun; Xu, Chang-Long; Wang, Jeffrey; Sun, Ying-Pu; Chian, Ri-Cheng

    2012-07-01

    system than without. Group embryo culture is superior to single embryo culture for blastocyst development. The WOW system with 50 μl of droplet of culture medium can be used to track the individual development of embryo cultured in groups while preserving good embryonic development. The reduced embryonic development with single embryo culture cannot be ameliorated by the WOW system.

  13. High resolution ultrasound-guided microinjection for interventional studies of early embryonic and placental development in vivo in mice

    PubMed Central

    Slevin, John C; Byers, Lois; Gertsenstein, Marina; Qu, Dawei; Mu, Junwu; Sunn, Nana; Kingdom, John CP; Rossant, Janet; Adamson, S Lee

    2006-01-01

    similar in sham experiments, 54% (33/61), for which procedures were identical but no microinjection was performed, suggesting that surgery and manipulation of the uterus were the main causes of embryonic death. Conclusion Ultrasound-guided microinjection into the ectoplacental cone region at E6.5 or E7.5 and the amniotic cavity at E7.5 was achieved with a 7 day postnatal survival of ≥60%. Target accuracy of these sites and of the exocoelomic cavity at E7.5 was ≥51%. We suggest that this approach may be useful for exploring gene function during early placental and embryonic development. PMID:16504164

  14. [Growth and oxygen consumption in embryonic and early postembryonic development of European pond turtle Emys orbicularis (Reptilia: Emydidae)].

    PubMed

    Vladimirova, I G; Alekseeva, T A; Nechaeva, M V

    2005-01-01

    Experiments on developing eggs of European pond turtle (Emys orbicularis) demonstrated S-shaped changes in the rate of oxygen consumption and body weight during embryonic development. The rate of oxygen consumption and weight progressively increased within 70 days after hatching. During embryogenesis, the rate of oxygen consumption decreased. After hatching, it increased but then decreased to a certain level, which remained constant to the end of the studied period. We observed unidirectional changes in oxygen consumption rate during embryonic period and this pattern was maintained after hatching as well. The coefficients of the allometric relationship between oxygen consumption and body weight were a = 0.33 and k = 0.52 during the embryonic period and a = 0.17 and k = 0.89 during the postembryonic period.

  15. The spawning, embryonic and early larval development of the green wrasse Labrus viridis (Linnaeus, 1758) (Labridae) in controlled conditions.

    PubMed

    Kožul, V; Glavić, N; Tutman, P; Bolotin, J; Onofri, V

    2011-05-01

    Green wrasse, Labrus viridis (Linnaeus, 1758), is an endangered species in the southern Adriatic Sea, but it is also of interest for potential rearing in polyculture with other commercial species for the repopulation of areas where it is endangered or as a new aquaculture species. A parental stock of the green wrasse was kept in aquaria for six years. The spawning, embryonic and early larval development maintained under controlled laboratory conditions are described and illustrated. The average diameter of newly spawned eggs was 1.01±0.03 mm. Mature and fertilized eggs were attached to the tank bottom by mucus. Hatching started after 127 h at a mean temperature of 14.4±0.8°C. The average total length of newly hatched larvae was 4.80±0.22 mm. Absorption of the yolk-sac was completed after the 5th day when larvae reached 5.87±0.28 mm. Larvae were fed with the rotifers Brachionus plicatilis. The pigmentation of L. viridis larvae is similar to that of Labrus merula and Labrus bergylta, but the main differences between these species are in the size of larvae and the development time of the melanophores on the anal fin-fold (five days later than with L. merula) and on top of the head (nine days earlier than with L. merula).

  16. Early intrauterine embryonic development in Khawia sinensis Hsü, 1935 (Cestoda, Caryophyllidea, Lytocestidae), an invasive tapeworm of carp (Cyprinus carpio): an ultrastructural study.

    PubMed

    Bruňanská, Magdaléna; Mackiewicz, John S; Młocicki, Daniel; Swiderski, Zdzisław; Nebesářová, Jana

    2012-02-01

    Intrauterine embryonic development in the caryophyllidean tapeworm Khawia sinensis has been investigated using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate for glycogen. Contrary to previous light microscopy findings that reported the release of non-embryonated eggs of K. sinenesis to the external environment, the present study documents various stages of embryonation (ovoviviparity) within the intrauterine eggs of this cestode. At the initial stage of embryonic development, each fertilised oocyte is accompanied by several vitellocytes that become enclosed within the operculate, electrondense shell. Cleavage divisions result in formation of blastomeres (up to about 24 cells) of various sizes. Mitotic divisions and apparent rosette arrangment of the blastomeres, the latter atypical within the Eucestoda, are observed for the first time in the intrauterine eggs of K. sinenesis. The early embryo enclosed within the electrondense shell is surrounded by a thin membraneous layer which in some enlarged regions shows presence of nuclei. Simultaneously to multiplication and differentiation, some of the blastomeres undergo deterioration. A progressive degeneration of the vitellocytes within eggs provides nutritive reserves, including lipids, for the developing embryo. The possible significance of this atypical timing of the intrauterine embryonic development to (1) the ecology of K. sinensis and that of a recent introduction of another invasive tapeworm, the caryophyllidean Atractolytocestus huronensis Anthony, 1958 to Europe; and (2) the affiliation of caryophyllideans with other lower cestodes, are discussed.

  17. Embryonic exposure of medaka (Oryzias latipes) to propylparaben: effects on early development and post-hatching growth.

    PubMed

    González-Doncel, Miguel; García-Mauriño, José Enrique; San Segundo, Laura; Beltrán, Eulalia M; Sastre, Salvador; Fernández Torija, Carlos

    2014-01-01

    Here we proposed a battery of non-invasive biomarkers and a histological survey to examine physiological/anatomical features in embryos, eleutheroembryos (13 days post-fertilization, dpf), and larvae (28-42 dpf) of medaka to investigate the effects of embryonic exposure to propylparaben (PrP). Concentrations <1000 μg PrP/L didn't exert early or late toxic effects. However, survivorship was affected at 4000 μg/L in eleutheroembryos and at ≥1000 μg/L in larvae. Histological alterations were found in 37.5% of eleutheroembryos exposed to 4000 μg PrP/L. Morphometric analysis of the gallbladder revealed significant dilation at ≥400 μg/L throughout embryo development. Ethoxyresorufin-O-deethylase (EROD), as indicator of cytochrome P4501A activity, didn't reveal induction/inhibition although its combination with a P4501A agonist (i.e. β-naphthoflavone) resulted in a synergic EROD response. Results suggest a low toxicity of PrP for fish and support the use of fish embryos and eleutheroembryos as alternatives of in vivo biomarkers indicative of exposure/toxicity.

  18. Transcription factor AP-2gamma is essential in the extra-embryonic lineages for early postimplantation development.

    PubMed

    Auman, Heidi J; Nottoli, Timothy; Lakiza, Olga; Winger, Quinton; Donaldson, Stephanie; Williams, Trevor

    2002-06-01

    The members of the AP-2 family of transcription factors play important roles during mammalian development and morphogenesis. AP-2gamma (Tcfap2c - Mouse Genome Informatics) is a retinoic acid-responsive gene implicated in placental development and the progression of human breast cancer. We show that AP-2gamma is present in all cells of preimplantation embryos and becomes restricted to the extra-embryonic lineages at the time of implantation. To study further the biological function of AP-2gamma, we have generated Tcfap2c-deficient mice by gene disruption. The majority of Tcfap2c(-/-) mice failed to survive beyond 8.5 days post coitum (d.p.c.). At 7.5 d.p.c., Tcfap2c(-/-) mutants were typically arrested or retarded in their embryonic development in comparison to controls. Morphological and molecular analyses of mutants revealed that gastrulation could be initiated and that anterior-posterior patterning of the epiblast remained intact. However, the Tcfap2c mutants failed to establish a normal maternal-embryonic interface, and the extra-embryonic tissues were malformed. Moreover, the trophoblast-specific expression of eomesodermin and Cdx2, two genes implicated in FGF-responsive trophoblast stem cell maintenance, was significantly reduced. Chimera studies demonstrated that AP-2gamma plays no major autonomous role in the development of the embryo proper. By contrast, the presence of AP-2gamma in the extra-embryonic membranes is required for normal development of this compartment and also for survival of the mouse embryo.

  19. Early intrauterine embryonic development of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost Merluccius merluccius (L., 1758) (Gadiformes: Merlucciidae).

    PubMed

    Swiderski, Zdzisław; Miquel, Jordi; Torres, Jordi; Delgado, Eulàlia

    2013-07-01

    The early intrauterine embryonic development of the bothriocephalidean cestode Clestobothrium crassiceps (Rudolphi, 1819), a parasite of the teleost Merluccius merluccius (L., 1758), was studied by means of light (LM) and transmission electron microscopy (TEM). Contrary to the generic diagnosis given in the CABI Keys to the cestode parasites of vertebrates, the eggs of C. crassiceps, the type of species of Clestobothrium Lühe, 1899, are operculate and embryonated. Our LM and TEM results provide direct evidence that an operculum is present and that the eggs exhibit various stages of intrauterine embryonic development, and in fact represent a good example of early ovoviviparity. The intrauterine eggs of this species are polylecithal and contain numerous vitellocytes, generally ∼30, which are pushed to the periphery and remain close to the eggshell, whereas the dividing zygote and later the early embryo remain in the egg centre. During early intrauterine embryonic development, several cleavage divisions take place, which result in the formation of three types of blastomeres, i.e. macro-, meso- and micromeres. These can be readily differentiated at the TEM level, not only by their size, but also by the ultrastructural characteristics of their nuclei and cytoplasmic organelles. The total number of blastomeres in these early embryos, enclosed within the electron-dense eggshells, can be up to ∼20 cells of various sizes and characteristics. Mitotic divisions of early blastomeres were frequently observed at both LM and TEM levels. Simultaneously with the mitotic cleavage divisions leading to blastomere multiplication and their rapid differentiation, there is also a deterioration of some blastomeres, mainly micromeres. A similar degeneration of vitellocytes begins even earlier. Both processes show a progressive degeneration of both vitellocytes and micromeres, and are good examples of apoptosis, a process that provides nutritive substances, including lipids, for the

  20. The interferon α-responsive gene, Ifrg15, plays vital roles during mouse early embryonic development.

    PubMed

    Yang, Ye; Wang, Jiayi; Zhao, Chun; Chen, Xiaojiao; Chen, Li; Zhang, Junqiang; Huo, Ran; Liu, Chang; Tong, Hua; Ling, Xiufeng

    2016-08-01

    The interferon alpha-responsive gene (Ifrg15) mRNA is highly expressed in various stages during preimplantation mammalian embryo development. Unfortunately, few studies have investigated the effect of Ifrg15 in this process. In mammals, the fusion of male and female pronuclei generates a diploid zygote, and is an important step for subsequent cleavage and blastocyst formation. Here, by using RNA interference, rescue experiments, immunofluorescence staining and live cell observations, we found that preimplantation embryo development was arrested at the 1-cell stage after knocking down Ifrg15 expression. This induced DNA damage and prevented the cleavage of embryos. Furthermore, the effect of Ifrg15 deficiency in arresting preimplantation embryo development produced by specific short interfering RNA microinjection was concentration-dependent. Using transcriptome expression profiles, gene ontogeny functional annotation and enrichment analysis, we gained 197 enriched pathways based on 1445 differentially expressed genes (DEGs). Of these, 12 pathways and about one third of the DEGs were involved in DNA damage, DNA repair, cell cycle, and developmental processes. Thus, the IFRG15 protein might be an important molecule for maintaining genomic integrity and stability through upregulating or downregulating a cascade of genes to permit normal preimplantation embryo development.

  1. Early embryonic development, assisted reproductive technologies, and pluripotent stem cell biology in domestic mammals.

    PubMed

    Hall, V; Hinrichs, K; Lazzari, G; Betts, D H; Hyttel, P

    2013-08-01

    Over many decades assisted reproductive technologies, including artificial insemination, embryo transfer, in vitro production (IVP) of embryos, cloning by somatic cell nuclear transfer (SCNT), and stem cell culture, have been developed with the aim of refining breeding strategies for improved production and health in animal husbandry. More recently, biomedical applications of these technologies, in particular, SCNT and stem cell culture, have been pursued in domestic mammals in order to create models for human disease and therapy. The following review focuses on presenting important aspects of pre-implantation development in cattle, pigs, horses, and dogs. Biological aspects and impact of assisted reproductive technologies including IVP, SCNT, and culture of pluripotent stem cells are also addressed.

  2. Mapping the early development of projections from the entorhinal cortex in the embryonic mouse using prenatal surgery techniques.

    PubMed

    Snyder, D C; Coltman, B W; Muneoka, K; Ide, C F

    1991-12-01

    The purpose of this work was to study the development of specific projections from the postero-lateral cortex during the third trimester of gestation in the mouse. To do this, we labeled undifferentiated lateral cortex with the fluorescent carbocyanine dye, Dil, in the embryonic day (E) 16 mouse embryo using exo utero surgical techniques (Muneoka, Wanek, and Bryant, 1986). Embryos were allowed to develop to term (postnatal day 0, P0) at which time the fiber patterns emanating from the marked regions were studied. Dye placement in the undifferentiated postero-ventral cortex produced labeled fibers in the hippocampal formation. A robust projection of the angular bundle into the CA1 region of the hippocampus was heavily labeled. In addition, in some animals, cortical tracts, such as the anterior commissure, corpus callosum, and a corticotectal tract, were labeled. These tracts have been described previously as scaffolding pathways in the fetal cat (McConnell, Ghosh, and Shatz, 1989), and other vertebrates (Wilson, Ross, Parrett, and Easter, 1990). Dye placement in adjacent, more anterior or dorsal areas showed strong labeling in cortical structures but no labeling in the hippocampal formation. These data indicate that, by birth, the temporal cortex is subdivided along the rostro-caudal axis as entorhinal cortex and perirhinal cortex, and along the dorso-ventral axis, as entorhinal cortex and neocortex. Also, these earliest connections are similar to adult connections in their specificity of target area selection. Therefore, these early, yet specific, connections may play a role int he formation of future connections during postnatal development.

  3. Ablation of Dido3 compromises lineage commitment of stem cells in vitro and during early embryonic development

    PubMed Central

    Fütterer, A; Raya, Á; Llorente, M; Izpisúa-Belmonte, J C; de la Pompa, J L; Klatt, P; Martínez-A, C

    2012-01-01

    The death inducer obliterator (Dido) locus encodes three protein isoforms, of which Dido3 is the largest and most broadly expressed. Dido3 is a nuclear protein that forms part of the spindle assembly checkpoint (SAC) and is necessary for correct chromosome segregation in somatic and germ cells. Here we report that specific ablation of Dido3 function in mice causes lethal developmental defects at the onset of gastrulation. Although these defects are associated with centrosome amplification, spindle malformation and a DNA damage response, we provide evidence that embryonic lethality of the Dido3 mutation cannot be explained by its impact on chromosome segregation alone. We show that loss of Dido3 expression compromises differentiation of embryonic stem cells in vitro and of epiblast cells in vivo, resulting in early embryonic death at around day 8.5 of gestation. Close analysis of Dido3 mutant embryoid bodies indicates that ablation of Dido3, rather than producing a generalized differentiation blockade, delays the onset of lineage commitment at the primitive endoderm specification stage. The dual role of Dido3 in chromosome segregation and stem cell differentiation supports the implication of SAC components in stem cell fate decisions. PMID:21660050

  4. Early events in xenograft development from the human embryonic stem cell line HS181--resemblance with an initial multiple epiblast formation.

    PubMed

    Gertow, Karin; Cedervall, Jessica; Jamil, Seema; Ali, Rouknuddin; Imreh, Marta P; Gulyas, Miklos; Sandstedt, Bengt; Ahrlund-Richter, Lars

    2011-01-01

    Xenografting is widely used for assessing in vivo pluripotency of human stem cell populations. Here, we report on early to late events in the development of mature experimental teratoma from a well-characterized human embryonic stem cell (HESC) line, HS181. The results show an embryonic process, increasingly chaotic. Active proliferation of the stem cell derived cellular progeny was detected already at day 5, and characterized by the appearance of multiple sites of engraftment, with structures of single or pseudostratified columnar epithelium surrounding small cavities. The striking histological resemblance to developing embryonic ectoderm, and the formation of epiblast-like structures was supported by the expression of the markers OCT4, NANOG, SSEA-4 and KLF4, but a lack of REX1. The early neural marker NESTIN was uniformly expressed, while markers linked to gastrulation, such as BMP-4, NODAL or BRACHYURY were not detected. Thus, observations on day 5 indicated differentiation comparable to the most early transient cell populations in human post implantation development. Confirming and expanding on previous findings from HS181 xenografts, these early events were followed by an increasingly chaotic development, incorporated in the formation of a benign teratoma with complex embryonic components. In the mature HS181 teratomas not all types of organs/tissues were detected, indicating a restricted differentiation, and a lack of adequate spatial developmental cues during the further teratoma formation. Uniquely, a kinetic alignment of rare complex structures was made to human embryos at diagnosed gestation stages, showing minor kinetic deviations between HS181 teratoma and the human counterpart.

  5. TGFbeta inhibition of yolk-sac-like differentiation of human embryonic stem-cell-derived embryoid bodies illustrates differences between early mouse and human development.

    PubMed

    Poon, Ellen; Clermont, Frederic; Firpo, Meri T; Akhurst, Rosemary J

    2006-02-15

    Transforming growth factor beta (TGFbeta) plays an important role in development and maintenance of murine yolk sac vascular development. Targeted deletions of Tgfb1 and other components of this signaling pathway, such as Acvrl1, Tgfbr1 and Tgfbr2, result in abnormal vascular development especially of the yolk sac, leading to embryonic lethality. There are significant differences between murine and primate development that limit interpretation of studies from mouse models. Thus, to examine the role of TGFbeta in early human vascular development we used the model of differentiating human embryonic stem cell-derived embryoid bodies to recapitulate early stages of embryonic development. TGFbeta was applied for different time frames after initiation of embryoid body cultures to assess its effect on differentiation. TGFbeta inhibited the expression of endodermal, endothelial and hematopoietic markers, which contrasts with findings in the mouse in which TGFbeta reduced the level of endodermal markers but increased endothelial marker expression. The inhibition observed was not due to changes in proliferation or apoptosis. This marked contrast between the two species may reflect the different origins of the yolk sac hemangiogenic lineages in mouse and human. TGFbeta effects on the hypoblast, from which these cell lineages are derived in human, would decrease subsequent differentiation of hematopoietic, endothelial and endodermal cells. By contrast, TGFbeta action on murine hypoblast, while affecting endoderm would not affect the hemangiogenic lineages that are epiblast-derived in the mouse. This study highlights important differences between early human and mouse embryonic development and suggests a role of TGFbeta in human hypoblast differentiation.

  6. Mechanotransduction in Embryonic Vascular Development

    PubMed Central

    Roman, Beth L.; Pekkan, Kerem

    2015-01-01

    A plethora of biochemical signals provides spatial and temporal cues that carefully orchestrate the complex process of vertebrate embryonic development. The embryonic vasculature develops not only in the context of these biochemical cues, but also in the context of the biomechanical forces imparted by blood flow. In the mature vasculature, different blood flow regimes induce distinct genetic programs, and significant progress has been made toward understanding how these forces are perceived by endothelial cells and transduced into biochemical signals. However, it cannot be assumed that paradigms that govern the mature vasculature are pertinent to the developing embryonic vasculature. The embryonic vasculature can respond to the mechanical forces of blood flow, and these responses are critical in vascular remodeling, certain aspects of sprouting angiogenesis, and maintenance of arterial-venous identity. Here, we review data regarding mechanistic aspects of endothelial cell mechanotransduction, with a focus on the response to shear stress, and elaborate upon the multifarious effects of shear stress on the embryonic vasculature. In addition, we discuss emerging predictive vascular growth models and highlight the prospect of combining signaling pathway information with computational modeling. We assert that correlation of precise measurements of hemodynamic parameters with effects on endothelial cell gene expression and cell behavior is required for fully understanding how blood flow-induced loading governs normal vascular development and shapes congenital cardiovascular abnormalities. PMID:22744845

  7. Muscular dystrophy begins early in embryonic development deriving from stem cell loss and disrupted skeletal muscle formation.

    PubMed

    Merrick, Deborah; Stadler, Lukas Kurt Josef; Larner, Dean; Smith, Janet

    2009-01-01

    Examination of embryonic myogenesis of two distinct, but functionally related, skeletal muscle dystrophy mutants (mdx and cav-3(-/-)) establishes for the first time that key elements of the pathology of Duchenne muscular dystrophy (DMD) and limb-girdle muscular dystrophy type 1C (LGMD-1c) originate in the disruption of the embryonic cardiac and skeletal muscle patterning processes. Disruption of myogenesis occurs earlier in mdx mutants, which lack a functional form of dystrophin, than in cav-3(-/-) mutants, which lack the Cav3 gene that encodes the protein caveolin-3; this finding is consistent with the milder phenotype of LGMD-1c, a condition caused by mutations in Cav3, and the earlier [embryonic day (E)9.5] expression of dystrophin. Myogenesis is severely disrupted in mdx embryos, which display developmental delays; myotube morphology and displacement defects; and aberrant stem cell behaviour. In addition, the caveolin-3 protein is elevated in mdx embryos. Both cav-3(-/-) and mdx mutants (from E15.5 and E11.5, respectively) exhibit hyperproliferation and apoptosis of Myf5-positive embryonic myoblasts; attrition of Pax7-positive myoblasts in situ; and depletion of total Pax7 protein in late gestation. Furthermore, both cav-3(-/-) and mdx mutants have cardiac defects. In cav-3(-/-) mutants, there is a more restricted phenotype comprising hypaxial muscle defects, an excess of malformed hypertrophic myotubes, a twofold increase in myonuclei, and reduced fast myosin heavy chain (FMyHC) content. Several mdx mutant embryo pathologies, including myotube hypotrophy, reduced myotube numbers and increased FMyHC, have reciprocity with cav-3(-/-) mutants. In double mutant (mdxcav-3(+/-)) embryos that are deficient in dystrophin (mdx) and heterozygous for caveolin-3 (cav-3(+/-)), whereby caveolin-3 is reduced to 50% of wild-type (WT) levels, these phenotypes are severely exacerbated: intercostal muscle fibre density is reduced by 71%, and Pax7-positive cells are depleted

  8. Muscular dystrophy begins early in embryonic development deriving from stem cell loss and disrupted skeletal muscle formation

    PubMed Central

    Merrick, Deborah; Stadler, Lukas Kurt Josef; Larner, Dean; Smith, Janet

    2009-01-01

    SUMMARY Examination of embryonic myogenesis of two distinct, but functionally related, skeletal muscle dystrophy mutants (mdx and cav-3−/−) establishes for the first time that key elements of the pathology of Duchenne muscular dystrophy (DMD) and limb-girdle muscular dystrophy type 1C (LGMD-1c) originate in the disruption of the embryonic cardiac and skeletal muscle patterning processes. Disruption of myogenesis occurs earlier in mdx mutants, which lack a functional form of dystrophin, than in cav-3−/− mutants, which lack the Cav3 gene that encodes the protein caveolin-3; this finding is consistent with the milder phenotype of LGMD-1c, a condition caused by mutations in Cav3, and the earlier [embryonic day (E)9.5] expression of dystrophin. Myogenesis is severely disrupted in mdx embryos, which display developmental delays; myotube morphology and displacement defects; and aberrant stem cell behaviour. In addition, the caveolin-3 protein is elevated in mdx embryos. Both cav-3−/− and mdx mutants (from E15.5 and E11.5, respectively) exhibit hyperproliferation and apoptosis of Myf5-positive embryonic myoblasts; attrition of Pax7-positive myoblasts in situ; and depletion of total Pax7 protein in late gestation. Furthermore, both cav-3−/− and mdx mutants have cardiac defects. In cav-3−/− mutants, there is a more restricted phenotype comprising hypaxial muscle defects, an excess of malformed hypertrophic myotubes, a twofold increase in myonuclei, and reduced fast myosin heavy chain (FMyHC) content. Several mdx mutant embryo pathologies, including myotube hypotrophy, reduced myotube numbers and increased FMyHC, have reciprocity with cav-3−/− mutants. In double mutant (mdxcav-3+/−) embryos that are deficient in dystrophin (mdx) and heterozygous for caveolin-3 (cav-3+/−), whereby caveolin-3 is reduced to 50% of wild-type (WT) levels, these phenotypes are severely exacerbated: intercostal muscle fibre density is reduced by 71%, and Pax7-positive

  9. Pipette-based Method to Study Embryoid Body Formation Derived from Mouse and Human Pluripotent Stem Cells Partially Recapitulating Early Embryonic Development Under Simulated Microgravity Conditions

    NASA Astrophysics Data System (ADS)

    Shinde, Vaibhav; Brungs, Sonja; Hescheler, Jürgen; Hemmersbach, Ruth; Sachinidis, Agapios

    2016-06-01

    The in vitro differentiation of pluripotent stem cells partially recapitulates early in vivo embryonic development. More recently, embryonic development under the influence of microgravity has become a primary focus of space life sciences. In order to integrate the technique of pluripotent stem cell differentiation with simulated microgravity approaches, the 2-D clinostat compatible pipette-based method was experimentally investigated and adapted for investigating stem cell differentiation processes under simulated microgravity conditions. In order to keep residual accelerations as low as possible during clinorotation, while also guaranteeing enough material for further analysis, stem cells were exposed in 1-mL pipettes with a diameter of 3.5 mm. The differentiation of mouse and human pluripotent stem cells inside the pipettes resulted in the formation of embryoid bodies at normal gravity (1 g) after 24 h and 3 days. Differentiation of the mouse pluripotent stem cells on a 2-D pipette-clinostat for 3 days also resulted in the formation of embryoid bodies. Interestingly, the expression of myosin heavy chain was downregulated when cultivation was continued for an additional 7 days at normal gravity. This paper describes the techniques for culturing and differentiation of pluripotent stem cells and exposure to simulated microgravity during culturing or differentiation on a 2-D pipette clinostat. The implementation of these methodologies along with -omics technologies will contribute to understand the mechanisms regulating how microgravity influences early embryonic development.

  10. Fertilization and early embryonic development in heifers and lactating cows in summer and lactating and dry cows in winter.

    PubMed

    Sartori, R; Sartor-Bergfelt, R; Mertens, S A; Guenther, J N; Parrish, J J; Wiltbank, M C

    2002-11-01

    Two experiments in two seasons evaluated fertilization rate and embryonic development in dairy cattle. Experiment 1 (summer) compared lactating Holstein cows (n = 27; 97.3 +/- 4.1 d postpartum [dppl; 40.0 +/- 1.5 kg milk/d) to nulliparous heifers (n = 28; 11 to 17 mo old). Experiment 2 (winter) compared lactating cows (n = 27; 46.4 +/- 1.6 dpp; 45.9 +/- 1.4 kg milk/d) to dry cows (n = 26). Inseminations based on estrus included combined semen from four high-fertility bulls. Embryos and oocytes recovered 5 d after ovulation were evaluated for fertilization, embryo quality (1 = excellent to 5 = degenerate), nuclei/embryo, and accessory sperm. In experiment 1, 21 embryos and 17 unfertilized oocytes (UFO) were recovered from lactating cows versus 32 embryos and no UFO from heifers (55% vs. 100% fertilization). Embryos from lactating cows had inferior quality scores (3.8 +/- 0.4 vs. 2.2 +/- 0.3), fewer nuclei/embryo (19.3 +/- 3.7 vs. 36.8 +/- 3.0) but more accessory sperm (37.3 +/- 5.8 vs. 22.4 +/- 5.5/embryo) than embryos from heifers. Sperm were attached to 80% of UFO (17.8 +/- 12.1 sperm/UFO). In experiment 2, lactating cows yielded 36 embryos and 5 UFO versus 34 embryos and 4 UFO from dry cows (87.8 vs. 89.5% fertilization). Embryo quality from lactating cows was inferior to dry cows (3.1 +/- 0.3 vs. 2.2 +/- 0.3), but embryos had similar numbers of nuclei (27.2 +/- 2.7 vs. 30.6 +/- 2.1) and accessory sperm (42.0 +/- 9.4 vs. 36.5 +/- 6.3). From 53% of the flushings from lactating cows and 28% from dry cows, only nonviable embryos were collected. Thus, embryos of lactating dairy cows were detectably inferior to embryos from nonlactating females as early as 5 d after ovulation, with a surprisingly high percentage of nonviable embryos. In addition, fertilization rate was reduced only in summer, apparently due to an effect of heat stress on the oocyte.

  11. Human embryonic stem cells: prospects for development.

    PubMed

    Pera, Martin F; Trounson, Alan O

    2004-11-01

    It is widely anticipated that human embryonic stem (ES) cells will serve as an experimental model for studying early development in our species, and, conversely, that studies of development in model systems, the mouse in particular, will inform our efforts to manipulate human stem cells in vitro. A comparison of primate and mouse ES cells suggests that a common underlying blueprint for the pluripotent state has undergone significant species-specific modification. As we discuss here, technical advances in the propagation and manipulation of human ES cells have improved our understanding of their growth and differentiation, providing the potential to investigate early human development and to develop new clinical therapies.

  12. Profiles of mRNA expression of related genes in the duck hypothalamus-pituitary growth axis during embryonic and early post-hatch development.

    PubMed

    Hu, Yan; Liu, Hongxiang; Song, Chi; Xu, Wenjuan; Ji, Gaige; Zhu, Chunhong; Shu, Jingting; Li, Huifang

    2015-03-15

    In this study, the ontogeny of body and liver weight and the pattern of related gene mRNA expression in the hypothalamus-pituitary growth axis (HPGA) of two different duck breeds (Anas platyrhynchos domestica) were compared during embryonic and post-hatch development. Duck hypothalamic growth hormone release hormone (GHRH), somatostatin (SS), pituitary growth hormone (GH), liver growth hormone receptor (GHR) and insulin-like growth factor-I (IGF-1) mRNA were first detected on the 13th embryonic day. During early duck development, SS maintained a lower expression status, whereas the other four genes exhibited highly significant variations in an age-specific manner. Highly significant breed specificity was observed with respect to hepatic IGF-1 mRNA expression, which showed a significant breed-age interaction effect. Compared with previous studies on chickens, significant species differences were observed regarding the mRNA expression of bird embryonic HPGA-related genes. During early development, highly significant breed and age specificity were observed with respect to developmental changes in body and liver weight, and varying degrees of significant linear correlation were found between these performances and the mRNA expression of HPGA-related genes in the duck HPGA. These results suggest that different genetic backgrounds may lead to differences in duck growth and HPGA-related gene mRNA expression, and the differential mRNA expression of related genes in the duck HPGA may be particularly important in the early growth of ducks. Furthermore, hepatic IGF-1 mRNA expression presented highly significant breed specificity, and evidence suggests the involvement of hepatic IGF-1 in mediating genetic effects on embryo and offspring growth in ducks.

  13. [Microglial cells and development of the embryonic central nervous system].

    PubMed

    Legendre, Pascal; Le Corronc, Hervé

    2014-02-01

    Microglia cells are the macrophages of the central nervous system with a crucial function in the homeostasis of the adult brain. However, recent studies showed that microglial cells may also have important functions during early embryonic central nervous system development. In this review we summarize recent works on the extra embryonic origin of microglia, their progenitor niche, the pattern of their invasion of the embryonic central nervous system and on interactions between embryonic microglia and their local environment during invasion. We describe microglial functions during development of embryonic neuronal networks, including their roles in neurogenesis, in angiogenesis and developmental cell death. These recent discoveries open a new field of research on the functions of neural-microglial interactions during the development of the embryonic central nervous system.

  14. Neural differentiation from human embryonic stem cells as a tool to study early brain development and the neuroteratogenic effects of ethanol.

    PubMed

    Taléns-Visconti, Raquel; Sanchez-Vera, Irene; Kostic, Jelena; Perez-Arago, Maria Amparo; Erceg, Slaven; Stojkovic, Miodrag; Guerri, Consuelo

    2011-02-01

    The in vitro generation of neural cells from human embryonic stem cells is a powerful tool to acquire better knowledge of the cellular and molecular events involved in early human neural and brain development under physiological and pathological conditions. Prenatal alcohol exposure can induce important anomalies in the developing brain, the embryogenesis being an important critical period for the craniofacial defects and mental disabilities associated with fetal alcohol syndrome. Here, we report the generation of neural progenitors (NPs) from human embryonic stem cells. Neuroepithelial progenitors display the morphological and functional characteristics of their embryonic counterparts and the proper timing of neurons and glia cells generation. Immunocytochemical and real time (RT)-polymerase chain reaction analyses reveal that cells appeared as clusters during neuroepithelial cell proliferation and that the genes associated with the neuroectodermal (Pax-6) and the endodermic (α-fetoprotein) lineages decreased in parallel to the upregulation of the genes of NPs (nestin and Tuj1), followed by their differentiation into neurons (MAP-2+, GABA+), oligodendrocytes [galactocerebroside (GalC+)], and astrocytes (GFAP+). We further demonstrate, for the first time, that human NPs express the endocannabinoid receptors (CB1 and CB2) and the enzymes involved in endocannabinoids synthesis (NAPE-PLD) and degradation (FAAH). Using this in vitro culture, we demonstrate that ethanol exposure impairs NPs survival, affects the differentiation of NPs into neurons and astrocytes, disrupts the actin cytoskeleton, and affects the expression of different genes associated with neural differentiation. The results provide new insights into the effects of ethanol on human embryogenesis and neuroprogenitors and offer an opportunity to delineate potential therapeutic strategies to restore early ethanol-induced brain damage.

  15. Evidence supporting a role for SMAD2/3 in bovine early embryonic development: potential implications for embryotropic actions of follistatin.

    PubMed

    Zhang, Kun; Rajput, Sandeep K; Lee, Kyung-Bon; Wang, Dongliang; Huang, Juncheng; Folger, Joseph K; Knott, Jason G; Zhang, Jiuzhen; Smith, George W

    2015-10-01

    The TGF-beta-SMAD signaling pathway is involved in regulation of various aspects of female reproduction. However, the intrinsic functional role of SMADs in early embryogenesis remains poorly understood. Previously, we demonstrated that treatment with follistatin, an activin (TGF-beta superfamily ligand)-binding protein, is beneficial for bovine early embryogenesis and specific embryotropic actions of follistatin are dependent on SMAD4. Because SMAD4 is a common SMAD that can bind both SMAD2/3 and SMAD1/5, the objective of this study was to further determine the intrinsic role of SMAD2/3 in the control of early embryogenesis and delineate if embryotropic actions of follistatin in early embryos are SMAD2/3 dependent. By using a combination of pharmacological and small interfering RNA-mediated inhibition of SMAD2/3 signaling in the presence or absence of follistatin treatment, our results indicate that SMAD2 and SMAD3 are both required for bovine early embryonic development and stimulatory actions of follistatin on 8- to 16-cell and that blastocyst rates, but not early cleavage, are muted when SMAD2/3 signaling is inhibited. SMAD2 deficiency also results in reduced expression of the bovine trophectoderm cell-specific gene CTGF. In conclusion, the present work provides evidence supporting a functional role of SMAD2/3 in bovine early embryogenesis and that specific stimulatory actions of follistatin are not observed in the absence of SMAD2/3 signaling.

  16. Evidence Supporting a Role for SMAD2/3 in Bovine Early Embryonic Development: Potential Implications for Embryotropic Actions of Follistatin1

    PubMed Central

    Zhang, Kun; Rajput, Sandeep K.; Lee, Kyung-Bon; Wang, Dongliang; Huang, Juncheng; Folger, Joseph K.; Knott, Jason G.; Zhang, Jiuzhen; Smith, George W.

    2015-01-01

    The TGF-beta-SMAD signaling pathway is involved in regulation of various aspects of female reproduction. However, the intrinsic functional role of SMADs in early embryogenesis remains poorly understood. Previously, we demonstrated that treatment with follistatin, an activin (TGF-beta superfamily ligand)-binding protein, is beneficial for bovine early embryogenesis and specific embryotropic actions of follistatin are dependent on SMAD4. Because SMAD4 is a common SMAD that can bind both SMAD2/3 and SMAD1/5, the objective of this study was to further determine the intrinsic role of SMAD2/3 in the control of early embryogenesis and delineate if embryotropic actions of follistatin in early embryos are SMAD2/3 dependent. By using a combination of pharmacological and small interfering RNA-mediated inhibition of SMAD2/3 signaling in the presence or absence of follistatin treatment, our results indicate that SMAD2 and SMAD3 are both required for bovine early embryonic development and stimulatory actions of follistatin on 8- to 16-cell and that blastocyst rates, but not early cleavage, are muted when SMAD2/3 signaling is inhibited. SMAD2 deficiency also results in reduced expression of the bovine trophectoderm cell-specific gene CTGF. In conclusion, the present work provides evidence supporting a functional role of SMAD2/3 in bovine early embryogenesis and that specific stimulatory actions of follistatin are not observed in the absence of SMAD2/3 signaling. PMID:26289443

  17. Power law relationship between cell cycle duration and cell volume in the early embryonic development of Caenorhabditis elegans.

    PubMed

    Arata, Yukinobu; Takagi, Hiroaki; Sako, Yasushi; Sawa, Hitoshi

    2014-01-01

    Cell size is a critical factor for cell cycle regulation. In Xenopus embryos after midblastula transition (MBT), the cell cycle duration elongates in a power law relationship with the cell radius squared. This correlation has been explained by the model that cell surface area is a candidate to determine cell cycle duration. However, it remains unknown whether this second power law is conserved in other animal embryos. Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution. Interestingly, the powers of the time-size relationship could be grouped into at least three classes: highly size-correlated, moderately size-correlated, and potentially a size-non-correlated class according to C. elegans founder cell lineages (1.2, 0.81, and <0.39 in radius, respectively). Thus, the power law relationship is conserved in Xenopus and C. elegans, while the absolute powers in C. elegans were different from that in Xenopus. Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes. The power of the volume relationship was closest to that of the time-size relationship in the highly size-correlated class. This correlation raised the possibility that the time-size relationship, at least in the highly size-correlated class, is explained by the volume ratio of nuclear size and cell size. Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures.

  18. Power law relationship between cell cycle duration and cell volume in the early embryonic development of Caenorhabditis elegans

    PubMed Central

    Arata, Yukinobu; Takagi, Hiroaki; Sako, Yasushi; Sawa, Hitoshi

    2015-01-01

    Cell size is a critical factor for cell cycle regulation. In Xenopus embryos after midblastula transition (MBT), the cell cycle duration elongates in a power law relationship with the cell radius squared. This correlation has been explained by the model that cell surface area is a candidate to determine cell cycle duration. However, it remains unknown whether this second power law is conserved in other animal embryos. Here, we found that the relationship between cell cycle duration and cell size in Caenorhabditis elegans embryos exhibited a power law distribution. Interestingly, the powers of the time-size relationship could be grouped into at least three classes: highly size-correlated, moderately size-correlated, and potentially a size-non-correlated class according to C. elegans founder cell lineages (1.2, 0.81, and <0.39 in radius, respectively). Thus, the power law relationship is conserved in Xenopus and C. elegans, while the absolute powers in C. elegans were different from that in Xenopus. Furthermore, we found that the volume ratio between the nucleus and cell exhibited a power law relationship in the size-correlated classes. The power of the volume relationship was closest to that of the time-size relationship in the highly size-correlated class. This correlation raised the possibility that the time-size relationship, at least in the highly size-correlated class, is explained by the volume ratio of nuclear size and cell size. Thus, our quantitative measurements shed a light on the possibility that early embryonic C. elegans cell cycle duration is coordinated with cell size as a result of geometric constraints between intracellular structures. PMID:25674063

  19. Expression analysis of the insulin-like growth factors I and II during embryonic and early larval development of turbot ( Scophthalmus maximus)

    NASA Astrophysics Data System (ADS)

    Wen, Haishen; Qi, Qian; Hu, Jian; Si, Yufeng; He, Feng; Li, Jifang

    2015-04-01

    The insulin-like growth factors I and II (IGF-I and IGF-II) are important proteins involved in fish growth and development. Here, we report the isolation of IGF-II and expression analysis of IGFs in turbot Scophthalmus maximus, aiming to clarify their function in embryonic and larval development of fish. The deduced IGF-II gene is 808 bp in full length, which encodes a protein of 219 amino acids and is 93% similar with that of Paralichthys olicaceus in amino acid sequence. The tissue abundance and the expression pattern of IGFs in a turbot at early development stages were investigated via reverse transcription-polymer chain reaction. Result showed that the IGF-I and IGF-II genes were widely expressed in tissues of S. maximus. IGF-I was detected in all tissues except intestines with the highest level in liver, while IGF-II transcript presented in all tissues except muscle. At the stages of embryonic and larval development, the mRNA levels of IGFs sharply increased from the stage of unfertilized egg to post larva, followed by a decrease with larval development. However, there was an increase in IGF-I at the embryonic stage and IGF-II at the gastrula stage, respectively. These results suggested that IGFs play important roles in cell growth and division of the turbot. Our study provides reference data for further investigation of growth regulation in turbot, which can guarantee better understanding of the physiological role that IGFs play in fish.

  20. Expression of insulin-like growth factor system genes in liver tissue during embryonic and early post-hatch development in duck (Anas platyrhynchos Domestica).

    PubMed

    Jianmin, Zou; Jingting, Shu; Yanju, Shan; Yan, Hu; Chi, Song; Wenqi, Zhu

    2014-04-03

    The IGF system is one of the most important endocrine and paracrine growth factor systems that regulate fetal and placental growth, whereas the liver is the principal source of circulation IGF-I. In the present study, expression of IGF-I, IGF type-I receptor (IGF-IR), and IGF binding protein (IGFBP)-3 genes was quantified by RT-PCR in the liver tissue on days 13, 17, 21, 25, and 27 of embryonic development, as well as at 7 days post-hatching (PH) in meat-type Gaoyou ducks and egg-type Jinding ducks. The results showed that IGF-I mRNA could be detected as early as on E 13d, but the expression level was low throughout embryonic development before increasing dramatically by E 27d and 7 days PH in both duck breeds. However, Gaoyou ducks exhibited higher IGF-I mRNA level than Jinding ducks, and the differences were significant on E 13d, E 21d, and at 7 days PH. Expression of IGF-IR in liver increased gradually in the former stages of the embryonic development, reaching its highest point on E 21d, and then declined up until 7 days PH. The expression pattern of IGFBP-3 gene was similar to that of IGF-IR gene, increasing significantly from E 17d. The expression peak appeared on E 25d, then declined significantly just prior to hatching (day 27) and was followed by an increase at 7 days PH. In general, the expression level of IGF-IR and IGFBP-3 genes in Jinding ducks was higher than that in Gaoyou ducks. Inverse relationships were observed for the expression of IGF-I and IGF-IR, and IGF-I and IGFBP-3, whereas a positive relationship was observed for the expression of IGF-IR and IGFBP-3. Our data indicate a differential expression of selected genes that comprise the IGF system in the duck liver tissue during embryonic and early PH growth and development.

  1. All-trans retinol and retinol-binding protein from embryonic cerebrospinal fluid exhibit dynamic behaviour during early central nervous system development.

    PubMed

    Parada, Carolina; Gato, Angel; Bueno, David

    2008-06-11

    Embryonic cerebrospinal fluid (E-CSF) is involved in the regulation of survival, proliferation and neurogenesis of neuroectodermal progenitor cells, as well as in the control of mesencephalic gene expression in collaboration with the isthmic organizer. Recently, we showed the presence of retinol-binding protein (RBP) within the E-CSF proteome. RBP is an all-trans retinol carrier, a molecule that can be metabolized into retinoic acid, a morphogen involved in central nervous system (CNS) morphogenesis and patterning. Here we demonstrate the presence of all-trans retinol within the E-CSF and analyse the dynamics of RBP and all-trans retinol within this fluid, as well as the expression of retinoic acid-synthesizing enzymes during early CNS development. Our results suggest a relationship between the dynamics of these molecules and the early events of CNS patterning.

  2. Effects of polyvinyl alcohol administered in the diet to rats on fertility, early embryonic development, growth and development.

    PubMed

    Rodwell, D E; Kelly, C M; DeMerlis, C C; Schoneker, D R; Borzelleca, J F

    2003-05-01

    PVA was administered in the diet to male and female Sprague-Dawley rats (26/sex/group) at doses of 0, 2000, 3500 and 5000 mg/kg/day for two generations. The study design assessed gonadal function, estrous cycle, mating behavior, conception, gestation, parturition, lactation, weaning, and growth and development of F(1) and F(2) offspring. Parental rats were treated for 70 days prior to mating, throughout mating, gestation and lactation until sacrifice. Clinical observations, body weights and feed consumption were recorded routinely. Dietary concentrations were adjusted for each sex on a weekly basis except during gestation and lactation, to provide the intended mg/kg/day PVA levels. Pups were weighed routinely and weaned at 21 days of age prior to selection for the next generation. Unformed stool was noted predominately at the 3500 and 5000 mg/kg/day levels in P(0) and F(1) parental animals. This finding was attributed to the high levels of PVA being fed and subsequently excreted in the stool. Slight decreases in the mean body weights of P(0) males were noted at 2000 and 5000 mg/kg/day. Feed consumption was elevated at the 3500 and 5000 mg/kg/day doses in both generations but not during either lactation period. These increases generally were observed in a dose-related manner (g/kg/day), as a result of the large amount of PVA being consumed to maintain the caloric intake necessary for normal growth. There were no effects of PVA on P(0), F(1) male or female reproductive performance or pup survival, growth, organ weights, and macroscopic or microscopic observations at doses of 2000, 3500 and 5000 mg/kg/day. Therefore the no-observed-effect level (NOAEL) is 5000 mg/kg/day for both parental and offspring in this reproductive study.

  3. Distinct and cooperative roles of mammalian Vg1 homologs GDF1 and GDF3 during early embryonic development.

    PubMed

    Andersson, Olov; Bertolino, Philippe; Ibáñez, Carlos F

    2007-11-15

    Vg1, a member of the TGF-beta superfamily of ligands, has been implicated in the induction of mesoderm, formation of primitive streak, and left-right patterning in Xenopus and chick embryos. In mice, GDF1 and GDF3 - two TGF-beta superfamily ligands that share high sequence identity with Vg1 - have been shown to independently mimic distinct aspects of Vg1's functions. However, the extent to which the developmental processes controlled by GDF1 and GDF3 and the underlying signaling mechanisms are evolutionarily conserved remains unclear. Here we show that phylogenetic and genomic analyses indicate that Gdf1 is the true Vg1 ortholog in mammals. In addition, and similar to GDF1, we find that GDF3 signaling can be mediated by the type I receptor ALK4, type II receptors ActRIIA and ActRIIB, and the co-receptor Cripto to activate Smad-dependent reporter genes. When expressed in heterologous cells, the native forms of either GDF1 or GDF3 were incapable of inducing downstream signaling. This could be circumvented by using chimeric constructs carrying heterologous prodomains, or by co-expression with the Furin pro-protein convertase, indicating poor processing of the native GDF1 and GDF3 precursors. Unexpectedly, co-expression with Nodal - another TGF-beta superfamily ligand involved in mesoderm formation - could also expose the activities of native GDF1 and GDF3, suggesting a potentially novel mode of cooperation between these ligands. Functional complementarity between GDF1 and GDF3 during embryonic development was investigated by analyzing genetic interactions between their corresponding genes. This analysis showed that Gdf1(-/-);Gdf3(-/-) compound mutants are more severely affected than either Gdf1(-/-) or Gdf3(-/-) single mutants, with defects in the formation of anterior visceral endoderm and mesoderm that recapitulate Vg1 loss of function, suggesting that GDF1 and GDF3 together represent the functional mammalian homologs of Vg1.

  4. Assessment of cathepsin mRNA expression and enzymatic activity during early embryonic development in the yellowtail kingfish Seriola lalandi.

    PubMed

    Palomino, Jaime; Herrera, Giannina; Torres-Fuentes, Jorge; Dettleff, Phillip; Patel, Alok; Martínez, Víctor

    2017-02-21

    In pelagic species such as Seriola lalandi, survival of both the eggs and embryos depends on yolk processing during oocyte maturation and embryo development. The main enzymes involved in these processes are the cathepsins, which are essential for the hydration process, acquiring buoyancy and nutrition of the embryo before hatching. This study aimed to investigate the mRNA expression profiles of cathepsins B, D and L (catb, catd and catl) and the activity of these enzymes during early development in S. lalandi. We included previtellogenic oocytes (PO). All three enzymes were highly expressed in PO, but the expression was reduced throughout development. Between PO and recently spawned eggs (E1) the transcript to catb and catd decreased, unlike catl. Cathepsin B activity, showed stable levels between PO until blastula stage (E4). High activities levels of cathepsins D and L were observed in E1 in comparison with later developmental stages. Cathepsin L activity remained constant until E1, consistent with observations in other pelagic spawners, where its participation in a second protolithic cleavage of the yolk proteins, has been proposed for this enzyme. Their profiles of both mRNA expression and enzymatic activity indicate the importance of these enzymes during early development and suggest different roles in egg yolk processing for the hydration process and nutrition in early embryos in this species.

  5. Cloning of a novel phospholipase C-delta isoform from pacific purple sea urchin (Strongylocentrotus purpuratus) gametes and its expression during early embryonic development.

    PubMed

    Coward, Kevin; Owen, Helen; Poustka, Albert J; Hibbitt, Olivia; Tunwell, Richard; Kubota, Hiroki; Swann, Karl; Parrington, John

    2004-01-23

    Calcium (Ca(2+)) is a ubiquitous intracellular messenger, controlling a diverse range of cellular processes, including fertilization and development of the embryo. One of the key mechanisms involved in triggering intracellular calcium release is the generation of the second messenger inositol-1,4,5-phosphate (IP(3)) by the phospholipase C (PLC) class of enzymes. Although five distinct forms of PLC have been identified in mammals (beta, gamma, delta, epsilon, and zeta), only one, PLCgamma, has thus far been detected in echinoderms. In the present study, we describe the isolation of a cDNA encoding a novel PLC isoform of the delta (delta) subclass, PLC-deltasu, from the egg of the Pacific purple sea urchin Strongylocentrotus purpuratus. We also demonstrate the presence of this PLC within the sperm and in the early embryo. The PLC-deltasu cDNA (2.44kb) encodes a 742 amino acid polypeptide with an open reading frame of 84.6kDa and a pI of 6.04. All of the characteristic domains found in mammalian PLCdelta isoforms (PH domain, EF hands, an X-Y catalytic region, and a C2 domain) are present in PLC-deltasu. A homology search revealed that PLC-deltasu shares most sequence identity with bovine PLCdelta2 (39%). We present evidence that PLC-deltasu is expressed in unfertilized eggs, fertilized eggs, and in the early embryo. In addition to Northern and polymerase chain reaction (PCR) analyses, in situ hybridization experiments further demonstrated that the embryonic regions within which the PLC-deltasu transcript can be detected during early embryonic development are associated with the highest levels of proliferative activity, suggesting a possible involvement with metabolism or cell cycle regulation.

  6. Relationship between Intrauterine Bacterial Infection and Early Embryonic Developmental Arrest

    PubMed Central

    Yan, Shao-Fei; Liu, Xin-Yan; Cheng, Yun-Fei; Li, Zhi-Yi; Ou, Jie; Wang, Wei; Li, Feng-Qin

    2016-01-01

    Background: Early embryonic developmental arrest is the most commonly understudied adverse outcome of pregnancy. The relevance of intrauterine infection to spontaneous embryonic death is rarely studied and remains unclear. This study aimed to investigate the relationship between intrauterine bacterial infection and early embryonic developmental arrest. Methods: Embryonic chorion tissue and uterine swabs for bacterial detection were obtained from 33 patients who underwent artificial abortion (control group) and from 45 patients who displayed early embryonic developmental arrest (trial group). Results: Intrauterine bacterial infection was discovered in both groups. The infection rate was 24.44% (11/45) in the early embryonic developmental arrest group and 9.09% (3/33) in the artificial abortion group. Classification analysis revealed that the highest detection rate for Micrococcus luteus in the early embryonic developmental arrest group was 13.33% (6/45), and none was detected in the artificial abortion group. M. luteus infection was significantly different between the groups (P < 0.05 as shown by Fisher's exact test). In addition, no correlation was found between intrauterine bacterial infection and history of early embryonic developmental arrest. Conclusions: M. luteus infection is related to early embryonic developmental arrest and might be one of its causative factors. PMID:27270541

  7. Embryonic-stage-dependent changes in the level of eIF4E-binding proteins during early development of sea urchin embryos.

    PubMed

    Salaün, Patrick; Boulben, Sandrine; Mulner-Lorillon, Odile; Bellé, Robert; Sonenberg, Nahum; Morales, Julia; Cormier, Patrick

    2005-04-01

    The eukaryotic initiation factor 4E (eIF4E)-binding proteins (4E-BPs) inhibit translation initiation by binding eIF4E and preventing recruitment of the translation machinery to mRNA. We have previously shown that fertilization of sea urchin eggs triggers eIF4E-4E-BP complex dissociation and 4E-BP degradation. Here, we show that microinjection of eIF4E-binding motif peptide into unfertilized eggs delays the onset of the first mitosis triggered by fertilization, demonstrating that dissociation of the eIF4E-4E-BP complex is functionally important for the first mitotic division in sea urchin embryos. We also show by gel filtration analyses that eIF4E is present in unfertilized eggs as an 80 kDa molecular mass complex containing 4E-BP and a new 4E-BP of 40 kDa. Fertilization triggers the dissociation of eIF4E from these two 4E-BPs and triggers the rapid recruitment of eIF4E into a high-molecular-mass complex. Release of eIF4E from the two 4E-BPs is correlated with a decrease in the total level of both 4E-BPs following fertilization. Abundance of the two 4E-BPs has been monitored during embryonic development. The level of the two proteins remains very low during the rapid cleavage stage of early development and increases 8 hours after fertilization. These results demonstrate that these two 4E-BPs are down- and upregulated during the embryonic development of sea urchins. Consequently, these data suggest that eIF4E availability to other partners represents an important determinant of the early development of sea urchin embryos.

  8. Post-embryonic development of the Early Ordovician (ca. 480 Ma) trilobite Apatokephalus latilimbatus Peng, 1990 and the evolution of metamorphosis.

    PubMed

    Park, Tae-Yoon S; Kihm, Ji-Hoon

    2015-01-01

    In many marine invertebrates metamorphosis entails a shift from a free-swimming larva to a benthic juvenile or adult. However, how the metamorphosis-entailing "indirect development" in arthropods arose from direct-developing ancestor is poorly understood. Trilobites left a rich fossil record, and some trilobite lineages had a metamorphosis-undergoing early developmental stage, termed the "asaphoid protaspis"-stage, providing a good opportunity to elucidate the rise of indirect development. Among others, the Ordovician representatives of Remopleuridioidea are known to possess a highly bulbous "asaphoid protaspis," while the Furongian (Late Cambrian) remopleuridioidean genus Haniwa did not possess it. Here we show the post-embryonic development of the remopleuridioidean trilobite, Apatokephalus latilimbatus, from the Tremadocian (485.4 Ma-477.7 Ma) Dongjeom Formation, Korea. The post-embryonic development of A. latilimbatus contains a free-swimming "commutavi protaspis" (a term replacing "asaphoid protaspis"). Interestingly, the earlier protaspid stage shows more similar morphology and size to the meraspis than the commutavi protaspid stage does. This indicates that the commutavi protaspid stage was intercalated into the ancestral direct development as a specialized stage for a better dispersal, and thus the "commutavi protaspis" of A. latilimbatus represents the initial phase of the evolution of indirect development. The duration of the free-swimming phase became longer in more derived remoplueridioidean trilobites, implying that the intercalated free-swimming strategy became emphasized during subsequent evolution. The morphological gap between the commutavi protaspis and the subsequent earliest meraspis provides a convincing case for the "selective independence" of developmental stages, explaining the various morphologies of commutavi protaspides in many trilobite lineages.

  9. Mechanisms of embryonic stomach development.

    PubMed

    McCracken, Kyle W; Wells, James M

    2017-06-01

    The stomach is a digestive organ that has important roles in human physiology and pathophysiology. The developmental origin of the stomach is the embryonic foregut, which also gives rise a number of other structures. There are several signaling pathways and transcription factors that are known to regulate stomach development at different stages, including foregut patterning, stomach specification, and gastric regionalization. These developmental events have important implications in later homeostasis and disease in the adult stomach. Here we will review the literature that has shaped our current understanding of the molecular mechanisms that coordinate gastric organogenesis. Further we will discuss how developmental paradigms have guided recent efforts to differentiate stomach tissue from pluripotent stem cells. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Rho GTPases in embryonic development

    PubMed Central

    Duquette, Philippe M; Lamarche-Vane, Nathalie

    2014-01-01

    In the last decade, several mouse models for RhoA, Rac1, and Cdc42 have emerged and have contributed a great deal to understanding the precise functions of Rho GTPases at early stages of development. This review summarizes our current knowledge of various mouse models of tissue-specific ablation of Cdc42, Rac1, and RhoA with emphasis on early embryogenesis, epithelial and skin morphogenesis, tubulogenesis, development of the central nervous system, and limb development. PMID:25483305

  11. The thyroid hormone receptor gene (c-erbA alpha) is expressed in advance of thyroid gland maturation during the early embryonic development of Xenopus laevis.

    PubMed Central

    Banker, D E; Bigler, J; Eisenman, R N

    1991-01-01

    The c-erbA proto-oncogene encodes the thyroid hormone receptor, a ligand-dependent transcription factor which plays an important role in vertebrate growth and development. To define the role of the thyroid hormone receptor in developmental processes, we have begun studying c-erbA gene expression during the ontogeny of Xenopus laevis, an organism in which thyroid hormone has well-documented effects on morphogenesis. Using polymerase chain reactions (PCR) as a sensitive assay of specific gene expression, we found that polyadenylated erbA alpha RNA is present in Xenopus cells at early developmental stages, including the fertilized egg, blastula, gastrula, and neurula. By performing erbA alpha-specific PCR on reverse-transcribed RNAs from high-density sucrose gradient fractions prepared from early-stage embryos, we have demonstrated that these erbA transcripts are recruited to polysomes. Therefore, erbA is expressed in Xenopus development prior to the appearance of the thyroid gland anlage in tailbud-stage embryos. This implies that erbA alpha/thyroid hormone receptors may play ligand-independent roles during the early development of X. laevis. Quantitative PCR revealed a greater than 25-fold range in the steady-state levels of polyadenylated erbA alpha RNA across early stages of development, as expressed relative to equimolar amounts of total embryonic RNA. Substantial increases in the levels of erbA alpha RNA were noted at stages well after the onset of zygotic transcription at the mid-blastula transition, with accumulation of erbA alpha transcripts reaching a relative maximum in advance of metamorphosis. We also show that erbA alpha RNAs are expressed unequally across Xenopus neural tube embryos. This differential expression continues through later stages of development, including metamorphosis. This finding suggests that erbA alpha/thyroid hormone receptors may play roles in tissue-specific processes across all of Xenopus development. Images PMID:1656222

  12. Precocious appearance of cardiac troponin T pre-mRNAs during early avian embryonic skeletal muscle development in ovo.

    PubMed

    Swiderski, R E; Solursh, M

    1990-07-01

    Cardiac troponin T (cTNT), a component of the muscle contractile apparatus, is transiently expressed in skeletal muscle during avian limb development. While cTNT was first detected immunohistochemically in limb buds undergoing overt myogenic differentiation (Hamburger and Hamilton stage 26, about 5 days in ovo), RNA blot analyses of early, predifferentiated wing buds have revealed the presence of cTNT transcripts in limb buds as early as stage 23 (4 days in ovo). Steady-state cTNT poly(A) RNAs of stage 22 through stage 37 fore- and hindlimbs were compared using both cTNT cDNA and cTNT intron-specific probes. In the predifferentiated state, two incompletely processed RNAs (3.8 and 2.4 kb) were expressed in the absence of the mature cTNT transcript, while a third pre-mRNA (3.5 kb) appeared concomitantly with the mature mRNA as differentiation and development proceeded. In addition, a population of unique cTNT transcripts were expressed in a proximal to distal manner in wing buds which had undergone initial overt myogenic differentiation (stage 26). Some of the cTNT pre-mRNAs observed in premyogenic limbs appeared to accumulate stably in a tissue-specific manner, based on their absence from the cardiac poly(A) RNA population. These results suggest that the appearance of cardiac troponin T mRNA, as well as the polypeptide, may be regulated at multiple levels including RNA processing, stability, and/or translation during early skeletal muscle myogenesis.

  13. Embryonic development in Zungaro jahu.

    PubMed

    Marques, Camila; Faustino, Francine; Bertolucci, Bruno; Paes, Maria do Carmo Faria; Silva, Regiane Cristina da; Nakaghi, Laura Satiko Okada

    2017-02-01

    The aim of this study was to characterize the embryonic development of Zungaro jahu, a fresh water teleostei commonly known as 'jaú'. Samples were collected at pre-determined times from oocyte release to larval hatching and analysed under light microscopy, transmission electron microscopy and scanning electron microscopy. At the first collection times, the oocytes and eggs were spherical and yellowish, with an evident micropyle. Embryo development took place at 29.4 ± 1.5°C and was divided into seven stages: zygote, cleavage, morula, blastula, gastrula, organogenesis, and hatching. The differentiation of the animal and vegetative poles occured during the zygote stage, at 10 min post-fertilization (mpf), leading to the development of the egg cell at 15 mpf. From 20 to 75 mpf, successive cleavages resulted in the formation of 2, 4, 8, 16, 32 and 64 blastomeres. The morula stage was observed between 90 and 105 mpf, and the blastula and gastrula stage at 120 and 180 mpf; respectively. The end of the gastrula stage was characterized by the presence of the yolk plug at 360 mpf. Organogenesis followed, with differentiation of the cephalic and caudal regions, elongation of the embryo by the cephalo-caudal axis, and somitogenesis. Hatching occurred at 780 mpf, with mean larval total length of 3.79 ± 0.11 mm.

  14. Cloning, expression pattern, and potential role of apoptosis inhibitor 5 in the termination of embryonic diapause and early embryo development of Artemia sinica.

    PubMed

    Zhang, Shuang; Yao, Feng; Jing, Ting; Zhang, Mengchen; Zhao, Wei; Zou, Xiangyang; Sui, Linlin; Hou, Lin

    2017-09-10

    During the embryonic development of Artemia sinica, the diapause phenomenon can be induced by high salinity or low temperature conditions. The diapause embryo at the gastrula stage is maintained under the threat of apoptosis to guarantee the embryo's normal development. In this process, apoptosis inhibitor proteins play vital roles in protecting embryos against apoptosis. Apoptosis inhibitor5 (API5) plays a pivotal role in regulating the cell cycle and preventing programmed cell death after growth factor starvation. In the present study, we cloned the full-length cDNA representing the api5 gene from A. sinica (As-api5), which encodes a 372-amino acid protein. In situ hybridization experiments revealed that As-api5 expression is not tissue or organ specific. Quantitative real-time PCR analyses of the developmental expression of As-api5 showed that it reached its highest level at 10h, after which its expression decreased. High salinity and low temperature treatments increased the expression of As-api5. Western blotting was used to assess the abundance of As-API5 and related proteins (As-CyclinA, As-CyclinE, As-E2F1, As-CDK2, As-APAF1, and As-Caspase9). Downregulation of As-api5 expression using a short interfering RNA resulted in increased mortality and embryo malformation of A. sinica. Taken together, the results indicated that API5 plays a crucial role in embryonic diapause termination and early embryo development of A. sinica. Copyright © 2017. Published by Elsevier B.V.

  15. A quantitative reference transcriptome for Nematostella vectensis early embryonic development: a pipeline for de novo assembly in emerging model systems.

    PubMed

    Tulin, Sarah; Aguiar, Derek; Istrail, Sorin; Smith, Joel

    2013-01-01

    The de novo assembly of transcriptomes from short shotgun sequences raises challenges due to random and non-random sequencing biases and inherent transcript complexity. We sought to define a pipeline for de novo transcriptome assembly to aid researchers working with emerging model systems where well annotated genome assemblies are not available as a reference. To detail this experimental and computational method, we used early embryos of the sea anemone, Nematostella vectensis, an emerging model system for studies of animal body plan evolution. We performed RNA-seq on embryos up to 24 h of development using Illumina HiSeq technology and evaluated independent de novo assembly methods. The resulting reads were assembled using either the Trinity assembler on all quality controlled reads or both the Velvet and Oases assemblers on reads passing a stringent digital normalization filter. A control set of mRNA standards from the National Institute of Standards and Technology (NIST) was included in our experimental pipeline to invest our transcriptome with quantitative information on absolute transcript levels and to provide additional quality control. We generated >200 million paired-end reads from directional cDNA libraries representing well over 20 Gb of sequence. The Trinity assembler pipeline, including preliminary quality control steps, resulted in more than 86% of reads aligning with the reference transcriptome thus generated. Nevertheless, digital normalization combined with assembly by Velvet and Oases required far less computing power and decreased processing time while still mapping 82% of reads. We have made the raw sequencing reads and assembled transcriptome publically available. Nematostella vectensis was chosen for its strategic position in the tree of life for studies into the origins of the animal body plan, however, the challenge of reference-free transcriptome assembly is relevant to all systems for which well annotated gene models and independently

  16. A quantitative reference transcriptome for Nematostella vectensis early embryonic development: a pipeline for de novo assembly in emerging model systems

    PubMed Central

    2013-01-01

    Background The de novo assembly of transcriptomes from short shotgun sequences raises challenges due to random and non-random sequencing biases and inherent transcript complexity. We sought to define a pipeline for de novo transcriptome assembly to aid researchers working with emerging model systems where well annotated genome assemblies are not available as a reference. To detail this experimental and computational method, we used early embryos of the sea anemone, Nematostella vectensis, an emerging model system for studies of animal body plan evolution. We performed RNA-seq on embryos up to 24 h of development using Illumina HiSeq technology and evaluated independent de novo assembly methods. The resulting reads were assembled using either the Trinity assembler on all quality controlled reads or both the Velvet and Oases assemblers on reads passing a stringent digital normalization filter. A control set of mRNA standards from the National Institute of Standards and Technology (NIST) was included in our experimental pipeline to invest our transcriptome with quantitative information on absolute transcript levels and to provide additional quality control. Results We generated >200 million paired-end reads from directional cDNA libraries representing well over 20 Gb of sequence. The Trinity assembler pipeline, including preliminary quality control steps, resulted in more than 86% of reads aligning with the reference transcriptome thus generated. Nevertheless, digital normalization combined with assembly by Velvet and Oases required far less computing power and decreased processing time while still mapping 82% of reads. We have made the raw sequencing reads and assembled transcriptome publically available. Conclusions Nematostella vectensis was chosen for its strategic position in the tree of life for studies into the origins of the animal body plan, however, the challenge of reference-free transcriptome assembly is relevant to all systems for which well annotated

  17. Morphological features of lipid droplet transition during porcine oocyte fertilisation and early embryonic development to blastocyst in vivo and in vitro.

    PubMed

    Kikuchi, Kazuhiro; Ekwall, Hans; Tienthai, Paisan; Kawai, Yasuhiro; Noguchi, Junko; Kaneko, Hiroyuki; Rodriguez-Martinez, Heriberto

    2002-11-01

    Lipid content in mammalian oocytes or embryos differs among species, with bovine and porcine oocytes and embryos showing large cytoplasmic droplets. These droplets are considered to play important roles in energy metabolism during oocyte maturation, fertilisation and early embryonic development, and also in the freezing ability of oocytes or embryos; however, their detailed distribution or function is not well understood. In the present study, changes in the distribution and morphology of porcine lipid droplets during in vivo and in vitro fertilisation, in contrast to parthenogenetic oocyte activation, as well as during their development to blastocyst stage, were evaluated by transmission electron microscopy (TEM). The analysis of semi-thin and ultra-thin sections by TEM showed conspicuous, large, electron-dense lipid droplets, sometimes associated with mitochondrial aggregates in the oocytes, irrespective of whether the oocytes had been matured in vivo or in vitro. Immediately after sperm penetration, the electron density of the lipid droplets was lost in both the in vivo and in vitro oocytes, the reduction being most evident in the oocytes developed in vitro. Density was restored in the pronculear oocytes, fully in the in vivo specimens but only partially in the in vitro ones. The number and size of the droplets seemed, however, to have decreased. At 2- to 4-cell and blastocyst stages, the features of the lipid droplets were almost the same as those of pronuclear oocytes, showing a homogeneous or saturated density in the in vivo embryos but a marbled or partially saturated appearance in the in vitro embryos. In vitro matured oocytes undergoing parthenogenesis had lipid droplets that resembled those of fertilised oocytes until the pronuclear stage. Overall, results indicate variations in both the morphology and amount of cytoplasmic lipid droplets during porcine oocyte maturation, fertilisation and early embryo development as well as differences between in vivo

  18. Study on embryonic development and early growth of triploid and gynogenetic diploid left-eyed flounder, Paralichthys olivaceus (T. et S.)

    NASA Astrophysics Data System (ADS)

    You, Feng; Liu, Jing; Wang, Xin-Cheng; Xu, Yong-Li; Huang, Rui-Dong; Zhang, Pei-Jun

    2001-06-01

    The early effects of chromosomal manipulation of eggs and sperm on the yields of triploid and gynogenetic diploid larvae of Paralichthys olivaceus were investigated Triploidy was achieved by cold shocking fertilized eggs at 0 2°C for 45 minutes duration 5 minutes after, fertilization, and the induced triploidy rates were 31.2% 50% and the relative hatching rates were 53.3% 99%. Gynogenetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 2°C for 45 minutes duration 5 minutes after fertilization. The induced gynogenetic diploid rates and the relative hatching rates were 94% 96% and 48.5% 68.5% respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae according to Student’s t-test (α=0.05). The relationship between the early growth of the triploid experimental group larvae and that of gynogenetic diploid experimental group larvae was also studied.

  19. Embryonic and larval development and early behavior in grass carp, Ctenopharyngodon idella: implications for recruitment in rivers

    USGS Publications Warehouse

    George, Amy E.; Chapman, Duane C.

    2015-01-01

    With recent findings of grass carp Ctenopharyngodon idella in tributaries of the Great Lakes, information on developmental rate and larval behavior is critical to efforts to assess the potential for establishment within the tributaries of that region. In laboratory experiments, grass carp were spawned and eggs and larvae reared at two temperature treatments, one "cold" and one "warm", and tracked for developmental rate, egg size, and behavior. Developmental rate was quantified using Yi's (1988) developmental stages and the cumulative thermal units method. Grass carp had a thermal minimum of 13.5°C for embryonic stages and 13.3°C for larval stages. Egg size was related to temperature and maternal size, with the largest eggs coming from the largest females, and eggs were generally larger in warmer treatments. Young grass carp larvae exhibited upward and downward swimming interspersed with long periods of lying on the bottom. Swimming capacity increased with ontogeny, and larvae were capable of horizontal swimming and position holding with gas bladder emergence. Developmental rates, behavior, and egg attributes can be used in combination with physical parameters of a river to assess the risk that grass carp are capable of reproduction and recruitment in rivers.

  20. Embryonic and Larval Development and Early Behavior in Grass Carp, Ctenopharyngodon idella: Implications for Recruitment in Rivers

    PubMed Central

    George, Amy E.; Chapman, Duane C.

    2015-01-01

    With recent findings of grass carp Ctenopharyngodon idella in tributaries of the Great Lakes, information on developmental rate and larval behavior is critical to efforts to assess the potential for establishment within the tributaries of that region. In laboratory experiments, grass carp were spawned and eggs and larvae reared at two temperature treatments, one “cold” and one “warm”, and tracked for developmental rate, egg size, and behavior. Developmental rate was quantified using Yi’s (1988) developmental stages and the cumulative thermal units method. Grass carp had a thermal minimum of 13.5°C for embryonic stages and 13.3°C for larval stages. Egg size was related to temperature and maternal size, with the largest eggs coming from the largest females, and eggs were generally larger in warmer treatments. Young grass carp larvae exhibited upward and downward swimming interspersed with long periods of lying on the bottom. Swimming capacity increased with ontogeny, and larvae were capable of horizontal swimming and position holding with gas bladder emergence. Developmental rates, behavior, and egg attributes can be used in combination with physical parameters of a river to assess the risk that grass carp are capable of reproduction and recruitment in rivers. PMID:25822837

  1. Analysis of mtDNA variant segregation during early human embryonic development: a tool for successful NARP preimplantation diagnosis

    PubMed Central

    Steffann, J; Frydman, N; Gigarel, N; Burlet, P; Ray, P F; Fanchin, R; Feyereisen, E; Kerbrat, V; Tachdjian, G; Bonnefont, J‐P; Frydman, R; Munnich, A

    2006-01-01

    Background Diseases arising from mitochondrial DNA (mtDNA) mutations are usually serious pleiotropic disorders with maternal inheritance. Owing to the high recurrence risk in the progeny of carrier females, “at‐risk” couples often ask for prenatal diagnosis. However, reliability of such practices remains under debate. Preimplantation diagnosis (PGD), a theoretical alternative to conventional prenatal diagnosis, requires that the mutant load measured in a single cell from an eight cell embryo accurately reflects the overall heteroplasmy of the whole embryo, but this is not known to be the case. Objective To investigate the segregation of an mtDNA length polymorphism in blastomeres of 15 control embryos from four unrelated couples, the NARP mutation in blastomeres of three embryos from a carrier of this mutation. Results Variability of the mtDNA polymorphism heteroplasmy among blastomeres from each embryo was limited, ranging from zero to 19%, with a mean of 7%. PGD for the neurogenic ataxia retinitis pigmentosa (NARP) mtDNA mutation (8993T→G) was therefore carried out in the carrier mother of an affected child. One of three embryos was shown to carry 100% of mutant mtDNA species while the remaining two were mutation‐free. These two embryos were transferred, resulting in a singleton pregnancy with delivery of a healthy child. Conclusions This PGD, the first reported for a mtDNA mutation, illustrates the skewed meiotic segregation of the NARP mtDNA mutation in early human development. However, discrepancies between the segregation patterns of the NARP mutation and the HV2 polymorphism indicate that a particular mtDNA nucleotide variant might differentially influenced the mtDNA segregation, precluding any assumption on feasibility of PGD for other mtDNA mutations. PMID:16155197

  2. Effect of recombinant-LH and hCG in the absence of FSH on in vitro maturation (IVM) fertilization and early embryonic development of mouse germinal vesicle (GV)-stage oocytes.

    PubMed

    Dinopoulou, Vasiliki; Drakakis, Peter; Kefala, Stella; Kiapekou, Erasmia; Bletsa, Ritsa; Anagnostou, Elli; Kallianidis, Konstantinos; Loutradis, Dimitrios

    2016-06-01

    During in vitro maturation (IVM), intrinsic and extrinsic factors must co-operate properly in order to ensure cytoplasmic and nuclear maturation. We examined the possible effect of LH/hCG in the process of oocyte maturation in mice with the addition of recombinant LH (r-LH) and hCG in our IVM cultures of mouse germinal vesicle (GV)-stage oocytes. Moreover, the effects of these hormones on fertilization, early embryonic development and the expression of LH/hCG receptor were examined. Nuclear maturation of GV-stage oocytes was evaluated after culture in the presence of r-LH or hCG. Fertilization rates and embryonic development were assessed after 24h. Total RNA was isolated from oocytes of different stages of maturation and from zygotes and embryos of different stages of development in order to examine the expression of LH/hCG receptor, using RT-PCR. The in vitro nuclear maturation rate of GV-stage oocytes that received hCG was significantly higher compared to the control group. Early embryonic development was increased in the hCG and LH cultures of GV oocytes when LH was further added. The LH/hCG receptor was expressed in all stages of in vitro matured mouse oocytes and in every stage of early embryonic development. Addition of hCG in IVM cultures of mouse GV oocytes increased maturation rates significantly. LH, however, was more beneficial to early embryonic development than hCG. This suggests a promising new technique in basic science research or in clinical reproductive medicine. Copyright © 2016 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  3. A novel human SCAN/(Cys)2(His)2 zinc-finger transcription factor ZNF323 in early human embryonic development.

    PubMed

    Pi, Hualiang; Li, Yongqing; Zhu, Chuanbing; Zhou, Liang; Luo, Kaimei; Yuan, Wuzhou; Yi, Zhengfang; Wang, Yuequn; Wu, Xiushan; Liu, Mingyao

    2002-08-09

    The C(2)H(2) zinc-finger motif found in many transcription factors is thought to be important for nucleic acid binding and/or dimerization. Here, we have identified and characterized a novel zinc-finger gene named ZNF323 using degenerate primers from an early human embryo heart cDNA library. The predicted protein contains six different C(2)H(2) type zinc fingers and a SCAN box. ZNF323 maps to chromosome 6p22.1-22.3. The expression levels were different during different development stages of human embryo between 15 and 23 weeks. Northern blot analysis shows that a 3.2-kb transcript specific for ZNF323 was expressed at high levels in the lung, liver, and kidney, while weakly expressed in intestine, brain, muscle, cholecyst, heart, and pancreas. In adult tissues, ZNF323 is expressed at high levels in liver and kidney, weakly in lung, pancreas, brain, placenta, muscle, and heart. Taken together, these results indicate that ZNF323 is a member of the zinc-finger transcription factor family and may be involved in the development of multiple embryonic organs.

  4. Pattern formation during development of the embryonic cerebellum

    PubMed Central

    Dastjerdi, F. V.; Consalez, G. G.; Hawkes, R.

    2012-01-01

    The patterning of the embryonic cerebellum is vital to establish the elaborate zone and stripe architecture of the adult. This review considers early stages in cerebellar Purkinje cell patterning, from the organization of the ventricular zone to the development of Purkinje cell clusters—the precursors of the adult stripes. PMID:22493569

  5. The effects of pyridaben pesticide on the DNA integrity of sperms and early in vitro embryonic development in mice.

    PubMed

    Ebadi Manas, Ghodrat; Hasanzadeh, Shapour; Najafi, Golamreza; Parivar, Kazem; Yaghmaei, Parichehr

    2013-08-01

    Pyridaben, a pyridazinone derivative, is a new acaricide and insecticide for control of mites and some insects such as white flies, aphids and thrips. This study was designed to elucidate how pyridaben can affect the sperms' morphological parameters, its DNA integrity, and to estimate the effect of various quantities of pyridaben on in vitro fertilization rate. In this study, 80 adult male Balb/C strain mice were used. Animals were divided into control and two test groups. Control group received distilled water. The test group was divided into two subgroups, viz, high dose (212 mg/kg/day) and low dose (53 mg/kg/day) and they received the pyridaben, orally for duration of 45 days. The spermatozoa were obtained from caudae epididymides on day 45 in all groups. Sperm viability, protamin compression (nuclear maturity), DNA double-strand breaks, and in vitro fertilizing (IVF) ability were examined. The pyridaben treatment provoked a significant decrease in sperm population and viability in epididymides. The data obtained from this experiment revealed that, the pyridaben brings about negative impact on the sperm maturation and DNA integrity in a time-dependent manner, which consequently caused a significant (p<0.05) reduction in IVF capability. Embryo developing arrest was significantly (p<0.05) higher in treated than the control group. Theses results confirmed that, the pyridaben is able to induce DNA damage and chromatin abnormalities in spermatozoa which were evident by low IVF rate. This article extracted from Ph.D. thesis. (Ghodrat Ebadi Mans).

  6. Embryonic vaccines against cancer: an early history.

    PubMed

    Brewer, Bradley G; Mitchell, Robert A; Harandi, Amir; Eaton, John W

    2009-06-01

    Almost 100 years have passed since the seminal observations of Schöne showing that vaccination of animals with fetal tissue would prevent the growth of transplantable tumors. Many subsequent reports have affirmed the general idea that immunologic rejection of transplantable tumors, as well as prevention of carcinogenesis, may be affected by vaccination with embryonic/fetal material. Following a decade of intense research on this phenomenon during approximately 1964-1974, interest appears to have waned. This earlier experimental work may be particularly pertinent in view of the rising interest in so-called cancer stem cells. We believe that further work - perhaps involving the use of embryonic stem cells as immunogens - is warranted and that the results reviewed herein support the concept that vaccination against the appearance of cancers of all kinds is a real possibility.

  7. Reproductive and Developmental Toxicity of Orally Administered Botanical Composition, UP446-Part III: Effects on Fertility and Early Embryonic Development to Implantation in Sprague Dawley Rats.

    PubMed

    Yimam, Mesfin; Lee, Young-Chul; Hyun, Eu-Jin; Jia, Qi

    2015-08-01

    In recent years, high prevalence of adverse effects associated to the use of traditional medicines during pregnancy is becoming alarming due to the self-medication of oral supplements by expecting mothers without supervision. Many expectant mothers use alternative and complementary medicines as a supplement to conventional pregnancy management with an inherent belief of considering herbal remedies as harmless. To the contrary, herbal remedies could incur a potential teratogenic risk both to the child bearing mother and the developing fetuses when consumed before or at the time of gestation. Here, we describe the potential adverse effects of orally administered UP446, a standardized bioflavonoid composition from the roots of Scutellaria baicalensis and the heartwoods of Acacia catechu, on fertility and early embryonic development to implantation in Sprague Dawley rats at doses of 250, 500, and 1000 mg/kg. Besides body weight and food consumption, reproductive functions, sperm motility and morphology, estrus cycle, and fertility rate were monitored. There were no statistically significant differences in reproductive function in all UP446 treated groups in both genders. Test substance impacts on reproductive parameters were very minimal. Neither sperm motility nor morphology was affected as a result of oral UP446 administrations in males. There were no treatment-related effects on estrus cycle stages in females. No significant changes in necropsy or histopathology were observed for all the groups. Therefore, the no observed adverse effect level (NOAEL) of UP446 was considered to be 1000 mg/kg, the highest dose tested, in both genders. © 2015 Wiley Periodicals, Inc.

  8. Heparin and penicillamine-hypotaurine-epinephrine (PHE) solution during bovine in vitro fertilization procedures impair the quality of spermatozoa but improve normal oocyte fecundation and early embryonic development.

    PubMed

    Gonçalves, F S; Barretto, L S S; Arruda, R P; Perri, S H V; Mingoti, G Z

    2014-01-01

    The presence of heparin and a mixture of penicillamine, hypotaurine, and epinephrine (PHE) solution in the in vitro fertilization (IVF) media seem to be a prerequisite when bovine spermatozoa are capacitated in vitro, in order to stimulate sperm motility and acrosome reaction. The present study was designed to determine the effect of the addition of heparin and PHE during IVF on the quality and penetrability of spermatozoa into bovine oocytes and on subsequent embryo development. Sperm quality, evaluated by the integrity of plasma and acrosomal membranes and mitochondrial function, was diminished (P<0.05) in the presence of heparin and PHE. Oocyte penetration and normal pronuclear formation rates, as well as the percentage of zygotes presenting more than two pronuclei, was higher (P<0.05) in the presence of heparin and PHE. No differences were observed in cleavage rates between treatment and control (P>0.05). However, the developmental rate to the blastocyst stage was increased in the presence of heparin and PHE (P>0.05). The quality of embryos that reached the blastocyst stage was evaluated by counting the inner cell mass (ICM) and trophectoderm (TE) cell numbers and total number of cells; the percentage of ICM and TE cells was unaffected (P>0.05) in the presence of heparin and PHE (P<0.05). In conclusion, this study demonstrated that while the supplementation of IVF media with heparin and PHE solution impairs spermatozoa quality, it plays an important role in sperm capacitation, improving pronuclear formation, and early embryonic development.

  9. The effects of pyridaben pesticide on the DNA integrity of sperms and early in vitro embryonic development in mice

    PubMed Central

    Ebadi Manas, Ghodrat; Hasanzadeh, Shapour; Najafi, Golamreza; Parivar, Kazem; Yaghmaei, Parichehr

    2013-01-01

    Background: Pyridaben, a pyridazinone derivative, is a new acaricide and insecticide for control of mites and some insects such as white flies, aphids and thrips. Objective: This study was designed to elucidate how pyridaben can affect the sperms' morphological parameters, its DNA integrity, and to estimate the effect of various quantities of pyridaben on in vitro fertilization rate. Materials and Methods: In this study, 80 adult male Balb/C strain mice were used. Animals were divided into control and two test groups. Control group received distilled water. The test group was divided into two subgroups, viz, high dose (212 mg/kg/day) and low dose (53 mg/kg/day) and they received the pyridaben, orally for duration of 45 days. The spermatozoa were obtained from caudae epididymides on day 45 in all groups. Sperm viability, protamin compression (nuclear maturity), DNA double-strand breaks, and in vitro fertilizing (IVF) ability were examined. Results: The pyridaben treatment provoked a significant decrease in sperm population and viability in epididymides. The data obtained from this experiment revealed that, the pyridaben brings about negative impact on the sperm maturation and DNA integrity in a time-dependent manner, which consequently caused a significant (p<0.05) reduction in IVF capability. Embryo developing arrest was significantly (p<0.05) higher in treated than the control group. Conclusion: Theses results confirmed that, the pyridaben is able to induce DNA damage and chromatin abnormalities in spermatozoa which were evident by low IVF rate. This article extracted from Ph.D. thesis. (Ghodrat Ebadi Mans) PMID:24639796

  10. 136 IMPACT OF SELECTION SYSTEM BY KINETICS ON THE EARLY EMBRYONIC DEVELOPMENT IN BOVINE OVUM PICKUP-IVF EMBRYOS.

    PubMed

    Takayama, M; Moriyoshi, M; Dochi, O; Imai, K

    2016-01-01

    Recently, in vitro-produced (IVP) embryos have been increasingly produced using ovum pickup (OPU) and IVF in cows worldwide. However, the conception rate of IVP embryos is lower than that of in vivo-derived embryos. This study was conducted to determine the proportion of embryos that led to a high conception rate when the embryos were selected according to the 4 predicting factors. A total of 30 Holstein and 20 Japanese Black cows were used, and 81 OPU-IVF sessions were performed from October 2014 to May 2016. The collected cumulus-oocyte complexes (COC) were cultured for 22h. Capacitated sperm (at a final concentration of 5×10(6) spermatozoa/mL) were incubated with COC for 6h. After insemination, presumptive zygotes were separated from cumulus cells and sperm by pipetting. Then, the presumptive zygotes were cultured for 9 days in CR1aa supplemented with 5% calf serum by using a micro-well culture dish (Dai Nippon Printing, Tokyo, Japan). The kinetics of embryo development was observed at 27, 31, and 55h post-insemination (hpi). The 4 factors used to select embryos were as follows: (1) time at which first cleavage occurred (less than 27hpi, or less than 31hpi, in case any of the zygotes did not cleave at 27hpi in each culture dish); (2) 2 blastomeres after first cleavage at 31hpi; (3) absence of fragments after first cleavage at 31hpi; and (4) 8 or more blastomeres at 55hpi. The number of blastocysts was analysed at 7, 8, and 9 days post IVF. Additionally, the number of produced embryos that could be used for embryo transfer (ET) was determined. The data were analysed using the chi-square test. The total numbers of blastocysts and produced embryos were 615 and 503, respectively. The numbers of blastocysts and produced embryos selected using the combination of factors 1 to 4 were 200 (32.5%) and 169 (27.5%), respectively. The numbers of blastocysts and produced embryos selected using factor 1 were 397 (64.6%) and 340 (67.6%), using factor 2 were 445 (71.3%) and 378

  11. Live 4D optical coherence tomography for early embryonic mouse cardiac phenotyping

    NASA Astrophysics Data System (ADS)

    Lopez, Andrew L.; Wang, Shang; Larin, Kirill V.; Overbeek, Paul A.; Larina, Irina V.

    2016-03-01

    Studying embryonic mouse development is important for our understanding of normal human embryogenesis and the underlying causes of congenital defects. Our research focuses on imaging early development in the mouse embryo to specifically understand cardiovascular development using optical coherence tomography (OCT). We have previously developed imaging approaches that combine static embryo culture, OCT imaging and advanced image processing to visualize the whole live mouse embryos and obtain 4D (3D+time) cardiodynamic datasets with cellular resolution. Here, we present the study of using 4D OCT for dynamic imaging of early embryonic heart in live mouse embryos to assess mutant cardiac phenotypes during development, including a cardiac looping defect. Our results indicate that the live 4D OCT imaging approach is an efficient phenotyping tool that can reveal structural and functional cardiac defects at very early stages. Further studies integrating live embryonic cardiodynamic phenotyping with molecular and genetic approaches in mouse mutants will help to elucidate the underlying signaling defects.

  12. [Embryonic development of 2 Phyllobothriidae (Cestoda: Tetraphyllidea)].

    PubMed

    Euzet, L; Mokhtar-Maamouri, F

    1976-01-01

    Caulobothrium longicolle (Linton, 1890) and Phyllobothrium gracile (Weld, 1855) (Cestoda: Tetraphyllidea, Phyllobothriidae) have the same embryonic development with the following characteristic data: --a small number of vitelline cells (2 or 3) pass with the zygote in the ootype;--a non operculate thin egg-shell;--the entire and equal zyhote cleavage following by unequal divisions leading to the formation of four blastomere types (Macromeres, secondary Macromere, Mesomeres and Micromeres);--the differentiation of two syncytial embryonic envelopes during the preoncospheral phase. The outer envelope encloses the vitelline material remnant and three Macromeres among which the secondary Macromere. The inner envelope or embryophore, originates from five or six Mesomeres;--the presence of the oncospheral membrane;--the Phyllobothriidae ontogenesis is similar to that of the Onchobothriidae. By their embryonic features, the Tetraphyllidea are close to the Cyclophyllidea. This similarity suggests a phylogenic relationship between those two Cestoda orders.

  13. Endothelin-1 signalling controls early embryonic heart rate in vitro and in vivo.

    PubMed

    Karppinen, S; Rapila, R; Mäkikallio, K; Hänninen, S L; Rysä, J; Vuolteenaho, O; Tavi, P

    2014-02-01

    Spontaneous activity of embryonic cardiomyocytes originates from sarcoplasmic reticulum (SR) Ca(2+) release during early cardiogenesis. However, the regulation of heart rate during embryonic development is still not clear. The aim of this study was to determine how endothelin-1 (ET-1) affects the heart rate of embryonic mice, as well as the pathway through which it exerts its effects. The effects of ET-1 and ET-1 receptor inhibition on cardiac contraction were studied using confocal Ca(2+) imaging of isolated mouse embryonic ventricular cardiomyocytes and ultrasonographic examination of embryonic cardiac contractions in utero. In addition, the amount of ET-1 peptide and ET receptor a (ETa) and b (ETb) mRNA levels were measured during different stages of development of the cardiac muscle. High ET-1 concentration and expression of both ETa and ETb receptors was observed in early cardiac tissue. ET-1 was found to increase the frequency of spontaneous Ca(2+) oscillations in E10.5 embryonic cardiomyocytes in vitro. Non-specific inhibition of ET receptors with tezosentan caused arrhythmia and bradycardia in isolated embryonic cardiomyocytes and in whole embryonic hearts both in vitro (E10.5) and in utero (E12.5). ET-1-mediated stimulation of early heart rate was found to occur via ETb receptors and subsequent inositol trisphosphate receptor activation and increased SR Ca(2+) leak. Endothelin-1 is required to maintain a sufficient heart rate, as well as to prevent arrhythmia during early development of the mouse heart. This is achieved through ETb receptor, which stimulates Ca(2+) leak through IP3 receptors. © 2013 Scandinavian Physiological Society. Published by John Wiley & Sons Ltd.

  14. PTBP1 Is Required for Embryonic Development before Gastrulation

    PubMed Central

    Suckale, Jakob; Wendling, Olivia; Masjkur, Jimmy; Jäger, Melanie; Münster, Carla; Anastassiadis, Konstantinos; Stewart, A. Francis; Solimena, Michele

    2011-01-01

    Polypyrimidine-tract binding protein 1 (PTBP1) is an important cellular regulator of messenger RNAs influencing the alternative splicing profile of a cell as well as its mRNA stability, location and translation. In addition, it is diverted by some viruses to facilitate their replication. Here, we used a novel PTBP1 knockout mouse to analyse the tissue expression pattern of PTBP1 as well as the effect of its complete removal during development. We found evidence of strong PTBP1 expression in embryonic stem cells and throughout embryonic development, especially in the developing brain and spinal cord, the olfactory and auditory systems, the heart, the liver, the kidney, the brown fat and cartilage primordia. This widespread distribution points towards a role of PTBP1 during embryonic development. Homozygous offspring, identified by PCR and immunofluorescence, were able to implant but were arrested or retarded in growth. At day 7.5 of embryonic development (E7.5) the null mutants were about 5x smaller than the control littermates and the gap in body size widened with time. At mid-gestation, all homozygous embryos were resorbed/degraded. No homozygous mice were genotyped at E12 and the age of weaning. Embryos lacking PTBP1 did not display differentiation into the 3 germ layers and cavitation of the epiblast, which are hallmarks of gastrulation. In addition, homozygous mutants displayed malformed ectoplacental cones and yolk sacs, both early supportive structure of the embryo proper. We conclude that PTBP1 is not required for the earliest isovolumetric divisions and differentiation steps of the zygote up to the formation of the blastocyst. However, further post-implantation development requires PTBP1 and stalls in homozygous null animals with a phenotype of dramatically reduced size and aberration in embryonic and extra-embryonic structures. PMID:21423341

  15. PTBP1 is required for embryonic development before gastrulation.

    PubMed

    Suckale, Jakob; Wendling, Olivia; Masjkur, Jimmy; Jäger, Melanie; Münster, Carla; Anastassiadis, Konstantinos; Stewart, A Francis; Solimena, Michele

    2011-02-17

    Polypyrimidine-tract binding protein 1 (PTBP1) is an important cellular regulator of messenger RNAs influencing the alternative splicing profile of a cell as well as its mRNA stability, location and translation. In addition, it is diverted by some viruses to facilitate their replication. Here, we used a novel PTBP1 knockout mouse to analyse the tissue expression pattern of PTBP1 as well as the effect of its complete removal during development. We found evidence of strong PTBP1 expression in embryonic stem cells and throughout embryonic development, especially in the developing brain and spinal cord, the olfactory and auditory systems, the heart, the liver, the kidney, the brown fat and cartilage primordia. This widespread distribution points towards a role of PTBP1 during embryonic development. Homozygous offspring, identified by PCR and immunofluorescence, were able to implant but were arrested or retarded in growth. At day 7.5 of embryonic development (E7.5) the null mutants were about 5x smaller than the control littermates and the gap in body size widened with time. At mid-gestation, all homozygous embryos were resorbed/degraded. No homozygous mice were genotyped at E12 and the age of weaning. Embryos lacking PTBP1 did not display differentiation into the 3 germ layers and cavitation of the epiblast, which are hallmarks of gastrulation. In addition, homozygous mutants displayed malformed ectoplacental cones and yolk sacs, both early supportive structure of the embryo proper. We conclude that PTBP1 is not required for the earliest isovolumetric divisions and differentiation steps of the zygote up to the formation of the blastocyst. However, further post-implantation development requires PTBP1 and stalls in homozygous null animals with a phenotype of dramatically reduced size and aberration in embryonic and extra-embryonic structures.

  16. Early embryonic androgen exposure induces transgenerational epigenetic and metabolic changes.

    PubMed

    Xu, Ning; Chua, Angela K; Jiang, Hong; Liu, Ning-Ai; Goodarzi, Mark O

    2014-08-01

    Androgen excess is a central feature of polycystic ovary syndrome (PCOS), which affects 6% to 10% of young women. Mammals exposed to elevated androgens in utero develop PCOS-like phenotypes in adulthood, suggesting fetal origins of PCOS. We hypothesize that excess androgen exposure during early embryonic development may disturb the epigenome and disrupt metabolism in exposed and unexposed subsequent generations. Zebrafish were used to study the underlying mechanism of fetal origins. Embryos were exposed to androgens (testosterone and dihydrotestosterone) early at 26 to 56 hours post fertilization or late at 21 to 28 days post fertilization. Exposed zebrafish (F0) were grown to adults and crossed to generate unexposed offspring (F1). For both generations, global DNA methylation levels were examined in ovaries using a luminometric methylation assay, and fasting and postprandial blood glucose levels were measured. We found that early but not late androgen exposure induced changes in global methylation and glucose homeostasis in both generations. In general, F0 adult zebrafish exhibited altered global methylation levels in the ovary; F1 zebrafish had global hypomethylation. Fasting blood glucose levels were decreased in F0 but increased in F1; postprandial glucose levels were elevated in both F0 and F1. This androgenized zebrafish study suggests that transient excess androgen exposure during early development can result in transgenerational alterations in the ovarian epigenome and glucose homeostasis. Current data cannot establish a causal relationship between epigenetic changes and altered glucose homeostasis. Whether transgenerational epigenetic alteration induced by prenatal androgen exposure plays a role in the development of PCOS in humans deserves study.

  17. Regulation of DNA Replication in Early Embryonic Cleavages

    PubMed Central

    Kermi, Chames; Lo Furno, Elena; Maiorano, Domenico

    2017-01-01

    Early embryonic cleavages are characterized by short and highly synchronous cell cycles made of alternating S- and M-phases with virtually absent gap phases. In this contracted cell cycle, the duration of DNA synthesis can be extraordinarily short. Depending on the organism, the whole genome of an embryo is replicated at a speed that is between 20 to 60 times faster than that of a somatic cell. Because transcription in the early embryo is repressed, DNA synthesis relies on a large stockpile of maternally supplied proteins stored in the egg representing most, if not all, cellular genes. In addition, in early embryonic cell cycles, both replication and DNA damage checkpoints are inefficient. In this article, we will review current knowledge on how DNA synthesis is regulated in early embryos and discuss possible consequences of replicating chromosomes with little or no quality control. PMID:28106858

  18. Altered expression of heat shock proteins in embryonal carcinoma and mouse early embryonic cells.

    PubMed

    Morange, M; Diu, A; Bensaude, O; Babinet, C

    1984-04-01

    In a previous paper, we have shown that in the absence of stress, mouse embryonal carcinoma cells, like mouse early embryo multipotent cells, synthesize high levels of 89- and 70-kilodalton heat shock proteins (HSP)(O. Bensaude and M. Morange, EMBO J. 2:173-177, 1983). We report here the pattern of proteins synthesized after a short period of hyperthermia in various mouse embryonal carcinoma cell lines and early mouse embryo cells. Among the various cell lines tested, two of them, PCC4-Aza R1 and PCC7-S-1009, showed an unusual response in that stimulation of HSP synthesis was not observed in these cells after hyperthermia. However, inducibility of 68- and 105-kilodalton HSP can be restored in PCC7-S-1009 cells after in vitro differentiation triggered by retinoic acid. Similarly, in the early mouse embryo, hyperthermia does not induce the synthesis of nonconstitutive HSP at the eight-cell stage, but induction of the 68-kilodalton HSP does occur at the blastocyst stage. Such a transition in the expression of HSP has already been described for Drosophila melanogaster and sea urchin embryos and recently for mouse embryos. It may be a general property of early embryonic cells.

  19. Altered expression of heat shock proteins in embryonal carcinoma and mouse early embryonic cells.

    PubMed Central

    Morange, M; Diu, A; Bensaude, O; Babinet, C

    1984-01-01

    In a previous paper, we have shown that in the absence of stress, mouse embryonal carcinoma cells, like mouse early embryo multipotent cells, synthesize high levels of 89- and 70-kilodalton heat shock proteins (HSP)(O. Bensaude and M. Morange, EMBO J. 2:173-177, 1983). We report here the pattern of proteins synthesized after a short period of hyperthermia in various mouse embryonal carcinoma cell lines and early mouse embryo cells. Among the various cell lines tested, two of them, PCC4-Aza R1 and PCC7-S-1009, showed an unusual response in that stimulation of HSP synthesis was not observed in these cells after hyperthermia. However, inducibility of 68- and 105-kilodalton HSP can be restored in PCC7-S-1009 cells after in vitro differentiation triggered by retinoic acid. Similarly, in the early mouse embryo, hyperthermia does not induce the synthesis of nonconstitutive HSP at the eight-cell stage, but induction of the 68-kilodalton HSP does occur at the blastocyst stage. Such a transition in the expression of HSP has already been described for Drosophila melanogaster and sea urchin embryos and recently for mouse embryos. It may be a general property of early embryonic cells. Images PMID:6546970

  20. [Effect of temperature on the rate of oxygen consumption during the second half of embryonic and early postembryonic development of European pond turtle Emys orbicularis (Reptilia: Emydidae)].

    PubMed

    Vladimirova, I G; Alekseeva, T A; Nechaeva, M V

    2005-01-01

    Oxygen consumption by eggs of European pond turtle was determined at two constant incubation temperatures of 25 and 28 degrees C during the second half of embryogenesis. During development at both temperatures, the rate of oxygen consumption initially increased to remain constant during the last quarter of embryogenesis. The difference between the rates of oxygen consumption at these temperatures decreased during the studied period. The coefficient Q10 for the rate of oxygen consumption decreased from 9 to 1.7. At an incubation temperature of 28 degrees C, the changes in the rate of oxygen consumption in response to a short-term temperature decrease to 25 degrees C or increase to 30 degrees C depended on the developmental stage and were most pronounced at the beginning of the studied period. During late embryonic and first 2.5 months of postembryonic development, the rate of oxygen consumption did not significantly differ after such temperature changes. The regulatory mechanisms formed during embryonic development are proposed to maintain the level of oxygen consumption during temperature changes.

  1. Embryonic development of Pelteobagrus fulvidraco (Richardson, 1846)

    NASA Astrophysics Data System (ADS)

    Wang, Weimin; Abbas, Khalid; Yan, Ansheng

    2006-12-01

    For production enhancement and procedure upgrade, the developmental phases of laboratory-reared eggs of catfish Pelteobagrus fulvidraco were investigated. Twenty mature females and 10 males were collected from Dadongmen wholesale fisheries market in Wuhan City on May 8, 2003. Zygotes were stripped from mature fish after hormone-induced ovulation, fertilized, and incubated through whole embryonic development. The fertilized eggs were stocked in density of 100 eggs/L in white square tanks of 10 L. Incubation water was dechlorinated tap water with continuous aeration. The tanks were lit directly with 60 W fluorescent bulbs with a 12 light: 12 dark photoperiod. Water temperature, dissolved oxygen and pH were 29.0±0.5°C, 6.7±0.4 mg/L and 7.4±2, respectively. The results showed that the eggs of P. fulvidraco were yellow, sticky and contained much yolk. The mean diameter of fertilized eggs was 2.03 mm. At the water temperature of 29.0±0.5°C, the ontogenesis spent about 33 h after fertilization. From fertilization to hatching, the embryonic development can be divided into 30 40 phases, which varies in the emphasis and direction of development. The detailed embryonic movement was also described.

  2. FGF-16 is required for embryonic heart development

    PubMed Central

    Lu, Shun Yan; Sheikh, Farah; Sheppard, Patricia C.; Fresnoza, Agnes; Duckworth, Mary Lynn; Detillieux, Karen A.; Cattini, Peter A.

    2016-01-01

    Fibroblast growth factor 16 (FGF-16) expression has previously been detected in mouse heart at mid-gestation in the endocardium and epicardium, suggesting a role in embryonic heart development. More specifically, exogenously applied FGF-16 has been shown to stimulate growth of embryonic myocardial cells in tissue explants. We have generated mice lacking FGF-16 by targeting the Fgf16 locus on the X chromosome. Elimination of Fgf16 expression resulted in embryonic death as early as day 11.5 (E11.5). External abnormalities, including hemorrhage in the heart and ventral body region as well as facial defects, began to appear in null embryos from E11.5. Morphological analysis of FGF-16 null hearts revealed cardiac defects including chamber dilation, thinning of the atrial and ventricular walls, and poor trabeculation, which were visible at E10.5 and more pronounced at E11.5. These findings indicate FGF-16 is required for embryonic heart development in mid-gestation through its positive effect on myocardial growth. PMID:18565327

  3. Informing tendon tissue engineering with embryonic development

    PubMed Central

    Glass, Zachary A.; Schiele, Nathan R.; Kuo, Catherine K.

    2014-01-01

    Tendon is a strong connective tissue that transduces muscle-generated forces into skeletal motion. In fulfilling this role, tendons are subjected to repeated mechanical loading and high stress, which may result in injury. Tissue engineering with stem cells offers the potential to replace injured/damaged tissue with healthy, new living tissue. Critical to tendon tissue engineering is the induction and guidance of stem cells towards the tendon phenotype. Typical strategies have relied on adult tissue homeostatic and healing factors to influence stem cell differentiation, but have yet to achieve tissue regeneration. A novel paradigm is to use embryonic developmental factors as cues to promote tendon regeneration. Embryonic tendon progenitor cell differentiation in vivo is regulated by a combination of mechanical and chemical factors. We propose that these cues will guide stem cells to recapitulate critical aspects of tenogenesis and effectively direct the cells to differentiate and regenerate new tendon. Here, we review recent efforts to identify mechanical and chemical factors of embryonic tendon development to guide stem/progenitor cell differentiation toward new tendon formation, and discuss the role this work may have in the future of tendon tissue engineering. PMID:24484642

  4. Informing tendon tissue engineering with embryonic development.

    PubMed

    Glass, Zachary A; Schiele, Nathan R; Kuo, Catherine K

    2014-06-27

    Tendon is a strong connective tissue that transduces muscle-generated forces into skeletal motion. In fulfilling this role, tendons are subjected to repeated mechanical loading and high stress, which may result in injury. Tissue engineering with stem cells offers the potential to replace injured/damaged tissue with healthy, new living tissue. Critical to tendon tissue engineering is the induction and guidance of stem cells towards the tendon phenotype. Typical strategies have relied on adult tissue homeostatic and healing factors to influence stem cell differentiation, but have yet to achieve tissue regeneration. A novel paradigm is to use embryonic developmental factors as cues to promote tendon regeneration. Embryonic tendon progenitor cell differentiation in vivo is regulated by a combination of mechanical and chemical factors. We propose that these cues will guide stem cells to recapitulate critical aspects of tenogenesis and effectively direct the cells to differentiate and regenerate new tendon. Here, we review recent efforts to identify mechanical and chemical factors of embryonic tendon development to guide stem/progenitor cell differentiation toward new tendon formation, and discuss the role this work may have in the future of tendon tissue engineering.

  5. The Meckel's cartilage in human embryonic and early fetal periods.

    PubMed

    Wyganowska-Świątkowska, Marzena; Przystańska, Agnieszka

    2011-06-01

    The Meckel's cartilage itself and the mandible are derived from the first branchial arch, and their development depends upon the contribution of the cranial neural crest cells. The prenatal development of the Meckel's cartilage, along with its relationship to the developing mandible and the related structures, were studied histologically in human embryos and fetuses. The material was obtained from a collection of the Department of Anatomy, and laboratory procedures were used to prepare sections, which were stained according to standard light-microscopy methods. The formation of the Meckel's cartilage and its related structures was observed and documented. Some critical moments in the development of the Meckel's cartilage are suggested. The sequential development of the Meckel's cartilage started as early as stage 13 (32 days) with the appearance of condensation of mesenchymal cells within the mandibular prominence. During stage 17 (41 days), the primary ossification center of the mandible appeared on the inferior margin of the Meckel's cartilage. The muscular attachments to the Meckel's cartilage in embryos were observed at stage 18 (44 days). Their subsequent movement into the developing mandible during the 10th week seemed to diminish the role of the Meckel's cartilage as the supportive core; simultaneously, the process of regression within the cartilage was induced. During the embryonic period, the bilateral Meckel's cartilages were in closest contact at the posterior surface of their superior margins, preceding formation of the symphyseal cartilage at this site. The event sequence in the development of the Meckel's cartilage is finally discussed.

  6. Establishing Pluripotency in Early Development

    PubMed Central

    Paranjpe, Sarita S.; Veenstra, Gert Jan C.

    2015-01-01

    The earliest steps of embryonic development involve important changes in chromatin and transcription factor networks, which are orchestrated to establish pluripotent cells that will form the embryo. DNA methylation, histone modifications, the pluripotency regulatory network of transcription factors, maternal factors and newly translated proteins all contribute to these transitions in dynamic ways. Moreover, these dynamics are linked to the onset of zygotic transcription. We will review recent progress in our understanding of chromatin state and regulation of gene expression in the context of embryonic development in vertebrates, in particular mouse, Xenopus and zebrafish. We include work on mouse embryonic stem cells and highlight work that illustrates how early embryonic dynamics establish gene regulatory networks and the state of pluripotency. PMID:25857441

  7. The 'ventral organs' of Pycnogonida (Arthropoda) are neurogenic niches of late embryonic and post-embryonic nervous system development.

    PubMed

    Brenneis, Georg; Scholtz, Gerhard

    2014-01-01

    Early neurogenesis in arthropods has been in the focus of numerous studies, its cellular basis, spatio-temporal dynamics and underlying genetic network being by now comparably well characterized for representatives of chelicerates, myriapods, hexapods and crustaceans. By contrast, neurogenesis during late embryonic and/or post-embryonic development has received less attention, especially in myriapods and chelicerates. Here, we apply (i) immunolabeling, (ii) histology and (iii) scanning electron microscopy to study post-embryonic ventral nerve cord development in Pseudopallene sp., a representative of the sea spiders (Pycnogonida), the presumable sister group of the remaining chelicerates. During early post-embryonic development, large neural stem cells give rise to additional ganglion cell material in segmentally paired invaginations in the ventral ectoderm. These ectodermal cell regions - traditionally designated as 'ventral organs' - detach from the surface into the interior and persist as apical cell clusters on the ventral ganglion side. Each cluster is a post-embryonic neurogenic niche that features a tiny central cavity and initially still houses larger neural stem cells. The cluster stays connected to the underlying ganglionic somata cortex via an anterior and a posterior cell stream. Cell proliferation remains restricted to the cluster and streams, and migration of newly produced cells along the streams seems to account for increasing ganglion cell numbers in the cortex. The pycnogonid cluster-stream-systems show striking similarities to the life-long neurogenic system of decapod crustaceans, and due to their close vicinity to glomerulus-like neuropils, we consider their possible involvement in post-embryonic (perhaps even adult) replenishment of olfactory neurons - as in decapods. An instance of a potentially similar post-embryonic/adult neurogenic system in the arthropod outgroup Onychophora is discussed. Additionally, we document two transient posterior

  8. Growth-promoting effects of different fractions of extra-embryonic coelomic fluid on embryonic development.

    PubMed

    Karabulut, A K; Layfield, R; Pratten, M K

    2000-08-01

    In the early stages of embryonic development, many growth-promoting molecules must be provided by the maternal system. These factors may be supplied locally to the embryo, by the decidua, the placenta, or the yolk sac. In this study the growth-promoting potential of extra-embryonic coelomic fluid (EECF) and its fractions was investigated. The embryonic requirement of growth-promoting molecules may be studied by reducing the growth-supporting capacity of serum. Thus, ultrafiltration of rat serum was carried out for 8 h using Millipore filters with a molecular weight exclusion of 30 kDa. Rat embryos at 9.5 days of age were cultured for 8 days for anembryonic yolk sacs, and then EECF was collected and divided into three different molecular weight fractions by ultrafiltration. Rat embryos were cultured for 48 h in whole rat serum and the serum retenate (which has low growth-supporting capacity) in the presence and absence of EECF, its fractions, or in EECF only. Embryos grown in retenate showed severe growth retardation, and the addition of EECF significantly improved embryonic growth. The fraction which contained the molecules with molecular weight between 10 and 30 kDa had significantly more effect on embryonic development than the other fractions. This fraction of EECF was analysed by gel electrophoresis. Three of the four protein bands observed in this fraction were identified by amino-terminal sequencing as alpha-fetoprotein precursor (22 kDa), apolipoprotein A1 precursor (24 kDa) and fetal haemoglobin Y2 chain (14 kDa), none of which are likely to be responsible for the growth-promoting activity. To further investigate growth-promoting proteins, EECF was Western-blotted to nitrocellulose membranes and probed with antisera against rat prolactin, epidermal growth factor, insulin-like growth factors I and II and human placental lactogen. No immunoreactive bands were detected in the EECF, suggesting that either these proteins are not present or are present at levels

  9. Effects of embryonic cyclosporine exposures on brain development and behavior.

    PubMed

    Clift, Danielle E; Thorn, Robert J; Passarelli, Emily A; Kapoor, Mrinal; LoPiccolo, Mary K; Richendrfer, Holly A; Colwill, Ruth M; Creton, Robbert

    2015-04-01

    Cyclosporine, a calcineurin inhibitor, is successfully used as an immunosuppressant in transplant medicine. However, the use of this pharmaceutical during pregnancy is concerning since calcineurin is thought to play a role in neural development. The risk for human brain development is difficult to evaluate because of a lack of basic information on the sensitive developmental times and the potentially pleiotropic effects on brain development and behavior. In the present study, we use zebrafish as a model system to examine the effects of embryonic cyclosporine exposures. Early embryonic exposures reduced the size of the eyes and brain. Late embryonic exposures did not affect the size of the eyes or brain, but did lead to substantial behavioral defects at the larval stages. The cyclosporine-exposed larvae displayed a reduced avoidance response to visual stimuli, low swim speeds, increased resting, an increase in thigmotaxis, and changes in the average distance between larvae. Similar results were obtained with the calcineurin inhibitor FK506, suggesting that most, but not all, effects on brain development and behavior are mediated by calcineurin inhibition. Overall, the results show that cyclosporine can induce either structural or functional brain defects, depending on the exposure window. The observed functional brain defects highlight the importance of quantitative behavioral assays when evaluating the risk of developmental exposures.

  10. Effects of embryonic cyclosporine exposures on brain development and behavior

    PubMed Central

    Clift, Danielle E.; Thorn, Robert J.; Passarelli, Emily A.; Kapoor, Mrinal; LoPiccolo, Mary K.; Richendrfer, Holly A.; Colwill, Ruth M.; Creton, Robbert

    2015-01-01

    Cyclosporine, a calcineurin inhibitor, is successfully used as an immunosuppressant in transplant medicine. However, the use of this pharmaceutical during pregnancy is concerning, since calcineurin is thought to play a role in neural development. The risk for human brain development is difficult to evaluate, because of a lack of basic information on the sensitive developmental times and the potentially pleiotropic effects on brain development and behavior. In the present study, we use zebrafish as a model system to examine the effects of embryonic cyclosporine exposures. Early embryonic exposures reduced the size of the eyes and brain. Late embryonic exposures did not affect the size of the eyes or brain, but did lead to substantial behavioral defects at the larval stages. The cyclosporine-exposed larvae displayed a reduced avoidance response to visual stimuli, low swim speeds, increased resting, an increase in thigmotaxis, and changes in the average distance between larvae. Similar results were obtained with the calcineurin inhibitor FK506, suggesting that most, but not all, effects on brain development and behavior are mediated by calcineurin inhibition. Overall, the results show that cyclosporine can induce either structural or functional brain defects, depending on the exposure window. The observed functional brain defects highlight the importance of quantitative behavioral assays when evaluating the risk of developmental exposures. PMID:25591474

  11. Cell Labeling and Injection in Developing Embryonic Mouse Hearts

    PubMed Central

    Dirschinger, Ralf J.; Evans, Sylvia M.; Puceat, Michel

    2014-01-01

    Testing the fate of embryonic or pluripotent stem cell-derivatives in in vitro protocols has led to controversial outcomes that do not necessarily reflect their in vivo potential. Preferably, these cells should be placed in a proper embryonic environment in order to acquire their definite phenotype. Furthermore, cell lineage tracing studies in the mouse after labeling cells with dyes or retroviral vectors has remained mostly limited to early stage mouse embryos with still poorly developed organs. To overcome these limitations, we designed standard and ultrasound-mediated microinjection protocols to inject various agents in targeted regions of the heart in mouse embryos at E9.5 and later stages of development.  Embryonic explant or embryos are then cultured or left to further develop in utero. These agents include fluorescent dyes, virus, shRNAs, or stem cell-derived progenitor cells. Our approaches allow for preservation of the function of the organ while monitoring migration and fate of labeled and/or injected cells. These technologies can be extended to other organs and will be very helpful to address key biological questions in biology of development. PMID:24797676

  12. Cytokinesis and the establishment of early embryonic cell polarity.

    PubMed

    Burgess, David R

    2008-06-01

    Cleavage divisions in many animals form a blastula made up of a simple polarized epithelium. This simple embryonic epithelium possesses an apical surface covered with microvilli and primary cilia separated from the basolateral surfaces by cell-cell junctions. The apical membrane proteins and lipids differ from those of the basolateral on these embryonic epithelial cells, as is found in adult epithelial cells. Formation of cell polarity in embryos at fertilization, including those from both protostomes and deuterostomes, uses the same molecules and signalling machinery as do polarizing epithelial cells that polarize upon cell-cell contact. In addition, the actin-myosin cytoskeleton plays an integral role in establishment and maintenance of this early cell polarity. However, early cleaving blastomeres from higher organisms including echinoderms and vertebrates have not been considered to exhibit cell polarity until formation of junctions at the third through to the fifth cleavage divisions. The role of new membrane addition into the late cleavage furrow during the early rounds of cytokinesis may play a key role in the early establishment of cell polarity in all animal embryos.

  13. Embryonic development of the Pacific lamprey, Entosphenus tridentatus.

    PubMed

    Yamazaki, Yuji; Fukutomi, Norio; Takeda, Korenori; Iwata, Akihisa

    2003-09-01

    Embryonic development of the Pacific lamprey, Entosphenus tridentatus, from Japan is described. Egg sizes averaged 1.249 mm (longest axis) and 1.145 mm (shortest axis), the time required for hatching being 11 days at 18 degrees C, shorter than previously reported for a lower water temperature (19 days at 15 degrees C). Early development in E. tridentatus proceeded at a similar rate to that in other lampreys, in spite of different rearing water temperatures for the latter, indicating possible specific differences in basic developmental rates.

  14. Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster Jasus edwardsii larvae (Decapoda:Palinuridae)

    PubMed Central

    Day, Ryan D.; McCauley, Robert D.; Fitzgibbon, Quinn P.; Semmens, Jayson M.

    2016-01-01

    Marine seismic surveys are used to explore for sub-seafloor oil and gas deposits. These surveys are conducted using air guns, which release compressed air to create intense sound impulses, which are repeated around every 8–12 seconds and can travel large distances in the water column. Considering the ubiquitous worldwide distribution of seismic surveys, the potential impact of exposure on marine invertebrates is poorly understood. In this study, egg-bearing female spiny lobsters (Jasus edwardsii) were exposed to signals from three air gun configurations, all of which exceeded sound exposure levels (SEL) of 185 dB re 1 μPa2·s. Lobsters were maintained until their eggs hatched and the larvae were then counted for fecundity, assessed for abnormal morphology using measurements of larval length and width, tested for larval competency using an established activity test and measured for energy content. Overall there were no differences in the quantity or quality of hatched larvae, indicating that the condition and development of spiny lobster embryos were not adversely affected by air gun exposure. These results suggest that embryonic spiny lobster are resilient to air gun signals and highlight the caution necessary in extrapolating results from the laboratory to real world scenarios or across life history stages. PMID:26947006

  15. Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster Jasus edwardsii larvae (Decapoda: Palinuridae).

    PubMed

    Day, Ryan D; McCauley, Robert D; Fitzgibbon, Quinn P; Semmens, Jayson M

    2016-03-07

    Marine seismic surveys are used to explore for sub-seafloor oil and gas deposits. These surveys are conducted using air guns, which release compressed air to create intense sound impulses, which are repeated around every 8-12 seconds and can travel large distances in the water column. Considering the ubiquitous worldwide distribution of seismic surveys, the potential impact of exposure on marine invertebrates is poorly understood. In this study, egg-bearing female spiny lobsters (Jasus edwardsii) were exposed to signals from three air gun configurations, all of which exceeded sound exposure levels (SEL) of 185 dB re 1 μPa(2) · s. Lobsters were maintained until their eggs hatched and the larvae were then counted for fecundity, assessed for abnormal morphology using measurements of larval length and width, tested for larval competency using an established activity test and measured for energy content. Overall there were no differences in the quantity or quality of hatched larvae, indicating that the condition and development of spiny lobster embryos were not adversely affected by air gun exposure. These results suggest that embryonic spiny lobster are resilient to air gun signals and highlight the caution necessary in extrapolating results from the laboratory to real world scenarios or across life history stages.

  16. Supplementation with spermine during in vitro maturation of porcine oocytes improves early embryonic development after parthenogenetic activation and somatic cell nuclear transfer.

    PubMed

    Jin, J X; Lee, S; Khoirinaya, C; Oh, A; Kim, G A; Lee, B C

    2016-03-01

    Spermine plays an important role in protection from reactive oxygen species (ROS) in bacteria, yeast, and mammalian cells, but there are few studies on the effects of spermine on porcine oocyte maturation and subsequent embryo development. The aim of this study was to determine the effects of spermine on in vitro maturation (IVM) of porcine oocytes and their developmental competence after parthenogenetic activation (PA) and somatic cell nuclear transfer (SCNT). We evaluated nuclear maturation, intracellular glutathione (GSH), and ROS levels in oocytes, and their subsequent embryonic development, as well as gene expression in mature oocytes, cumulus cells, and PA blastocysts. After treatment with various concentrations of spermine in IVM culture medium, there was no significant difference in nuclear maturation rate. However, spermine treatment groups (10- 500 µM) showed significantly increased intracellular GSH levels and decreased ROS levels compared to the control ( < 0.05). Furthermore, 10 µM spermine supported significantly higher blastocyst formation rates after PA than the control group ( < 0.05). According to the optimal condition from the PA results, we investigated the effects of 10 µM spermine on SCNT, and it also significantly improved blastocyst formation rates compared with the control group ( < 0.05). In evaluating the effects of 10 µM spermine on gene expression, there was significantly lower expression of a proapoptotic gene () and higher expression of an antiapoptotic gene () in cumulus cells ( < 0.05). was increased in spermine-treated oocytes. Levels of transcription for and were significantly increased in PA blastocysts. In conclusion, 10 µM spermine supplementation during IVM improved the development of porcine PA and SCNT embryos by increasing intracellular GSH, scavenging ROS levels, and regulating gene expression.

  17. Expression Patterns of Atlantic Sturgeon (Acipenser oxyrinchus) During Embryonic Development

    PubMed Central

    Kaitetzidou, Elisavet; Ludwig, Arne; Gessner, Jörn; Sarropoulou, Elena

    2016-01-01

    During teleost ontogeny the larval and embryonic stages are key stages, since failure during this period of tissue differentiation may cause malformations, developmental delays, poor growth, and massive mortalities. Despite the rapid advances in sequencing technologies, the molecular backgrounds of the development of economically important but endangered fish species like the Atlantic sturgeon (Acipenser oxyrinchus) have not yet been thoroughly investigated. The current study examines the differential expression of transcripts involved in embryonic development of the Atlantic sturgeon. Addressing this goal, a reference transcriptome comprising eight stages was generated using an Illumina HiSequation 2500 platform. The constructed de novo assembly counted to 441,092 unfiltered and 179,564 filtered transcripts. Subsequently, the expression profile of four developmental stages ranging from early (gastrula) to late stages of prelarval development [2 d posthatching (dph)] were investigated applying an Illumina MiSeq platform. Differential expression analysis revealed distinct expression patterns among stages, especially between the two early and the two later stages. Transcripts upregulated at the two early stages were mainly enriched in transcripts linked to developmental processes, while transcripts expressed at the last two stages were mainly enriched in transcripts important to muscle contraction. Furthermore, important stage-specific expression has been detected for the hatching stage with transcripts enriched in molecule transport, and for the 2 dph stage with transcripts enriched in visual perception and lipid digestion. Our investigation represents a significant contribution to the understanding of Atlantic sturgeon embryonic development, and transcript characterization along with the differential expression results will significantly contribute to sturgeon research and aquaculture. PMID:27974440

  18. Spatiotemporal development of the embryonic nervous system of Saccoglossus kowalevskii.

    PubMed

    Cunningham, Doreen; Casey, Elena Silva

    2014-02-01

    Defining the organization and temporal onset of key steps in neurogenesis in invertebrate deuterostomes is critical to understand the evolution of the bilaterian and deuterostome nervous systems. Although recent studies have revealed the organization of the nervous system in adult hemichordates, little attention has been paid to neurogenesis during embryonic development in this third major phylum of deuterostomes. We examine the early events of neural development in the enteropneust hemichordate Saccoglossus kowalevskii by analyzing the expression of 11 orthologs of key genes associated with neurogenesis in an expansive range of bilaterians. Using in situ hybridization (ISH) and RT-PCR, we follow the course of neural development to track the transition of the early embryonic diffuse nervous system to the more regionalized midline nervous system of the adult. We show that in Saccoglossus, neural progenitor markers are expressed maternally and broadly encircle the developing embryo. An increase in their expression and the onset of pan neural markers, indicate that neural specification occurs in late blastulae - early gastrulae. By mid-gastrulation, punctate expression of markers of differentiating neurons encircling the embryo indicate the presence of immature neurons, and at the end of gastrulation when the embryo begins to elongate, markers of mature neurons are expressed. At this stage, expression of a subset of neuronal markers is concentrated along the trunk ventral and dorsal midlines. These data indicate that the diffuse embryonic nervous system of Saccoglossus is transient and quickly reorganizes before hatching to resemble the adult regionalized, centralized nervous system. This regionalization occurs at a much earlier developmental stage than anticipated indicating that centralization is not linked in S. kowalevskii to a lifestyle change of a swimming larva metamorphosing to a crawling worm-like adult.

  19. Critical Transitions in Early Embryonic Aortic Arch Patterning and Hemodynamics

    PubMed Central

    Kowalski, William J.; Dur, Onur; Wang, Yajuan; Patrick, Michael J.; Tinney, Joseph P.; Keller, Bradley B.; Pekkan, Kerem

    2013-01-01

    Transformation from the bilaterally symmetric embryonic aortic arches to the mature great vessels is a complex morphogenetic process, requiring both vasculogenic and angiogenic mechanisms. Early aortic arch development occurs simultaneously with rapid changes in pulsatile blood flow, ventricular function, and downstream impedance in both invertebrate and vertebrate species. These dynamic biomechanical environmental landscapes provide critical epigenetic cues for vascular growth and remodeling. In our previous work, we examined hemodynamic loading and aortic arch growth in the chick embryo at Hamburger-Hamilton stages 18 and 24. We provided the first quantitative correlation between wall shear stress (WSS) and aortic arch diameter in the developing embryo, and observed that these two stages contained different aortic arch patterns with no inter-embryo variation. In the present study, we investigate these biomechanical events in the intermediate stage 21 to determine insights into this critical transition. We performed fluorescent dye microinjections to identify aortic arch patterns and measured diameters using both injection recordings and high-resolution optical coherence tomography. Flow and WSS were quantified with 3D computational fluid dynamics (CFD). Dye injections revealed that the transition in aortic arch pattern is not a uniform process and multiple configurations were documented at stage 21. CFD analysis showed that WSS is substantially elevated compared to both the previous (stage 18) and subsequent (stage 24) developmental time-points. These results demonstrate that acute increases in WSS are followed by a period of vascular remodeling to restore normative hemodynamic loading. Fluctuations in blood flow are one possible mechanism that impacts the timing of events such as aortic arch regression and generation, leading to the variable configurations at stage 21. Aortic arch variations noted during normal rapid vascular remodeling at stage 21 identify a

  20. The embryonic midbrain directs neuronal specification of embryonic stem cells at early stages of differentiation.

    PubMed

    Baizabal, José-Manuel; Covarrubias, Luis

    2009-01-01

    Specific neuronal differentiation of Embryonic Stem Cells (ESCs) depends on their capacity to interpret environmental cues. At present, it is not clear at which stage of differentiation ESCs become competent to produce multiple neuronal lineages in response to the niche of the embryonic brain. To unfold the developmental potential of ESC-derived precursors, we transplanted these cells into the embryonic midbrain explants, where neurogenesis occurs as in normal midbrain development. Using this experimental design, we show that the transition from ESCs to Embryoid Body (EB) precursors is necessary to differentiate into Lmx1a(+)/Ptx3(+)/TH(+) dopaminergic neurons around the ventral midline of the midbrain. In addition, EB cells placed at other dorsal-ventral levels of the midbrain give rise to Nkx6.1(+) red nucleus (RN) neurons, Nkx2.2(+) ventral interneurons and Pax7(+) dorsal neurons at the correct positions. Notably, differentiation of ESCs into Neural Precursor Cells (NPCs) prior to transplantation markedly reduces specification at the Lmx1a, Nkx6.1 and Pax7 expression domains, without affecting neuronal differentiation. Finally, exposure to Fgf8 and Shh in vitro promotes commitment of some ESC-derived NPCs to differentiate into putative Lmx1a(+) dopaminergic neurons in the midbrain. Our data demonstrate intrinsic developmental potential differences among ESC-derived precursor populations.

  1. Neuregulin 3 and erbb signalling networks in embryonic mammary gland development.

    PubMed

    Kogata, Naoko; Zvelebil, Marketa; Howard, Beatrice A

    2013-06-01

    We review the role of Neuregulin 3 (Nrg3) and Erbb receptor signalling in embryonic mammary gland development. Neuregulins are growth factors that bind and activate its cognate Erbb receptor tyrosine kinases, which form a signalling network with established roles in breast development and breast cancer. Studies have shown that Nrg3 expression profoundly impacts early stages of embryonic mammary development. Network analysis shows how Nrg/Erbb signals could integrate with other major regulators of embryonic mammary development to elicit the morphogenetic processes and cell fate decisions that occur as the mammary lineage is established.

  2. Embryonic cerebrospinal fluid in brain development: neural progenitor control.

    PubMed

    Gato, Angel; Alonso, M Isabel; Martín, Cristina; Carnicero, Estela; Moro, José Antonio; De la Mano, Aníbal; Fernández, José M F; Lamus, Francisco; Desmond, Mary E

    2014-08-28

    Due to the effort of several research teams across the world, today we have a solid base of knowledge on the liquid contained in the brain cavities, its composition, and biological roles. Although the cerebrospinal fluid (CSF) is among the most relevant parts of the central nervous system from the physiological point of view, it seems that it is not a permanent and stable entity because its composition and biological properties evolve across life. So, we can talk about different CSFs during the vertebrate life span. In this review, we focus on the CSF in an interesting period, early in vertebrate development before the formation of the choroid plexus. This specific entity is called "embryonic CSF." Based on the structure of the compartment, CSF composition, origin and circulation, and its interaction with neuroepithelial precursor cells (the target cells) we can conclude that embryonic CSF is different from the CSF in later developmental stages and from the adult CSF. This article presents arguments that support the singularity of the embryonic CSF, mainly focusing on its influence on neural precursor behavior during development and in adult life.

  3. Embryonic cerebrospinal fluid in brain development: neural progenitor control

    PubMed Central

    Gato, Angel; Alonso, M. Isabel; Martín, Cristina; Carnicero, Estela; Moro, José Antonio; De la Mano, Aníbal; Fernández, José M. F.; Lamus, Francisco; Desmond, Mary E.

    2014-01-01

    Due to the effort of several research teams across the world, today we have a solid base of knowledge on the liquid contained in the brain cavities, its composition, and biological roles. Although the cerebrospinal fluid (CSF) is among the most relevant parts of the central nervous system from the physiological point of view, it seems that it is not a permanent and stable entity because its composition and biological properties evolve across life. So, we can talk about different CSFs during the vertebrate life span. In this review, we focus on the CSF in an interesting period, early in vertebrate development before the formation of the choroid plexus. This specific entity is called “embryonic CSF.” Based on the structure of the compartment, CSF composition, origin and circulation, and its interaction with neuroepithelial precursor cells (the target cells) we can conclude that embryonic CSF is different from the CSF in later developmental stages and from the adult CSF. This article presents arguments that support the singularity of the embryonic CSF, mainly focusing on its influence on neural precursor behavior during development and in adult life. PMID:25165044

  4. Embryonic development of the cricket Gryllus bimaculatus.

    PubMed

    Donoughe, Seth; Extavour, Cassandra G

    2016-03-01

    Extensive research into Drosophila melanogaster embryogenesis has improved our understanding of insect developmental mechanisms. However, Drosophila development is thought to be highly divergent from that of the ancestral insect and arthropod in many respects. We therefore need alternative models for arthopod development that are likely to be more representative of basally-branching clades. The cricket Gryllus bimaculatus is such a model, and currently has the most sophisticated functional genetic toolkit of any hemimetabolous insect. The existing cricket embryonic staging system is fragmentary, and it is based on morphological landmarks that are not easily visible on a live, undissected egg. To address this problem, here we present a complementary set of "egg stages" that serve as a guide for identifying the developmental progress of a cricket embryo from fertilization to hatching, based solely on the external appearance of the egg. These stages were characterized using a combination of brightfield timelapse microscopy, timed brightfield micrographs, confocal microscopy, and measurements of egg dimensions. These egg stages are particularly useful in experiments that involve egg injection (including RNA interference, targeted genome modification, and transgenesis), as injection can alter the speed of development, even in control treatments. We also use 3D reconstructions of fixed embryo preparations to provide a comprehensive description of the morphogenesis and anatomy of the cricket embryo during embryonic rudiment assembly, germ band formation, elongation, segmentation, and appendage formation. Finally, we aggregate and schematize a variety of published developmental gene expression patterns. This work will facilitate further studies on G. bimaculatus development, and serve as a useful point of reference for other studies of wild type and experimentally manipulated insect development in fields from evo-devo to disease vector and pest management. Copyright

  5. Histology atlas of the developing mouse hepatobiliary hemolymphatic vascular system with emphasis on embryonic days 11.5-18.5 and early postnatal development

    USDA-ARS?s Scientific Manuscript database

    A critical event in fetal development is the proper formation of the vascular system, of which the hepatobiliary system plays a pivotal role. This has lead pathologists and scientists to utilize transgenic mice to identify developmental disorders associated with the hepatobiliary vascular system. Va...

  6. Expression and role of Elovl4 elongases in biosynthesis of very long-chain fatty acids during zebrafish Danio rerio early embryonic development.

    PubMed

    Monroig, Oscar; Rotllant, Josep; Cerdá-Reverter, José M; Dick, James R; Figueras, Antonio; Tocher, Douglas R

    2010-10-01

    Elovl4 is a fatty acyl elongase that participates in the biosynthesis of very long-chain fatty acids (>/=C24), which are relatively abundant in skin (saturated chains), or retina, brain and testes (polyunsaturated chains) of mammals. In the present study we characterised two Elovl4 proteins, Elovl4a and Elovl4b, from zebrafish Danio rerio, and investigated their expression patterns during embryonic development. Heterologous expression in baker's yeast showed that both zebrafish Elovl4 proteins efficiently elongated saturated fatty acids up to C36, with 26:0 appearing the preferred substrate as reported for human ELOVL4. Interestingly, activity for the elongation of PUFA substrates was only shown by Elovl4b, which effectively converted eicosapentaenoic (20:5n-3) and arachidonic (20:4n-6) acids to elongated polyenoic products up to C36. Furthermore, zebrafish Elovl4b may be involved in the biosynthesis of docosahexaenoic acid (22:6n-3, DHA) as it had the capacity to elongate 22:5n-3 to 24:5n-3 which can be subsequently desaturated and chain shortened to DHA in peroxisomes. The distinct functional roles of zebrafish Elovl4 proteins were also reflected in their spatial-temporal expression patterns during ontogeny. Analyses by whole-mount in situ hybridisation in zebrafish embryos showed that elovl4a was expressed in neuronal tissues (wide-spread distribution in the head area), with elovl4b specifically expressed in epiphysis (pineal gland) and photoreceptor cells in the retina. Similarly, tissue distribution in adults revealed that elovl4a transcripts were found in most tissues analysed, whereas elovl4b expression was essentially restricted to eye and gonads. Overall, the results suggest that zebrafish elovl4b resembles other mammalian orthologues in terms of function and expression patterns, whereas elovl4a may represent an alternative elongase not previously described in vertebrates. Copyright @ 2010 Elsevier B.V. All rights reserved.

  7. Localization in Oogenesis of Maternal Regulators of Embryonic Development.

    PubMed

    Escobar-Aguirre, Matias; Elkouby, Yaniv M; Mullins, Mary C

    2017-01-01

    Cell polarity generates intracellular asymmetries and functional regionalization in tissues and morphogenetic processes. Cell polarity in development often relies on mechanisms of RNA localization to specific subcellular domains to define the identity of future developing tissues. The totipotent egg of most animals illustrates in a grand way the importance of cell polarity and RNA localization in regulating multiple crucial developmental events. The polarization of the egg arises during its development in oogenesis. RNAs localize asymmetrically in the early oocyte defining its animal-vegetal (AV) axis, which upon further elaboration in mid- and late-oogenesis stages produces a mature egg with specific localized factors along its AV axis. These localized factors will define the future anterior-posterior (AP) and dorsal-ventral (DV) axes of the embryo. Furthermore, AV polarity confines germ cell determinants to the vegetal pole, from where they redistribute to the cleavage furrows of the 2- and 4-cell stage embryo, ultimately specifying the primordial germ cells (PGCs). The sperm entry region during fertilization is also defined by the AV axis. In frogs and fish, sperm enters through the animal pole, similar to the mouse where it enters predominantly in the animal half. Thus, AV polarity establishment and RNA localization are involved in all the major events of early embryonic development. In this chapter, we will review the RNA localization mechanisms in vertebrate oocytes that are key to embryonic patterning, referring to some of the groundbreaking studies in frog oocytes and incorporating the current genetic evidence from the zebrafish.

  8. Avian embryonic development in hyperdynamic environments

    NASA Technical Reports Server (NTRS)

    Abbott, U. K.; Smith, A. H.

    1983-01-01

    Embryos which developed for 24 hours in the oviduct of hens maintained at 2 G and which were subsequently incubated at Earth gravity had a 14% reduction in hatchability. Increased mortality during the first 4 days, and an increase in embryonic abnormalities were of the types usually found during the first mortality peak (2-3 days). Embryos in eggs that were produced at Earth gravity and continued their development on the centrifuge at fields of 2 G or less did not appear to be greatly affected by the treatment. At 4 G, 91% of the embryos died, mostly on the first and second days of incubation. Abnormalities prominent in the centrifuged eggs include: (a) a failure of the primitive streak to develop; (b) interference with the development of the axial skeleton; (c) multiple hemorrhages, mostly petechial which is consistent with capillary fragility; and (d) retardation of embryo growth, possibly caused by an interference with gaseous diffusion, the result of an acceleration-induced increase in gas density in the centrifuging incubator.

  9. Early asymmetry of gene transcription between embryonic human left and right cerebral cortex

    PubMed Central

    Sun, Tao; Patoine, Christina; Abu-Khalil, Amir; Visvader, Jane; Sum, Eleanor; Cherry, Timothy J.; Orkin, Stuart H.; Geschwind, Daniel H.; Walsh, Christopher A.

    2009-01-01

    The human left and right cerebral hemispheres are anatomically and functionally asymmetric. To test whether human cortical asymmetry has a molecular basis, we studied gene expression levels between the left and right embryonic hemispheres using Serial Analysis of Gene Expression (SAGE), and identified and verified 27 differentially expressed genes, suggesting that human cortical asymmetry is accompanied by early, striking transcriptional asymmetries. LMO4 is consistently more highly expressed in the right perisylvian human cerebral cortex than in the left, and is essential for cortical development in mice, suggesting that human left-right specialization reflects asymmetric cortical development at early stages. PMID:15894532

  10. Normal table of embryonic development in the four-toed salamander, Hemidactylium scutatum.

    PubMed

    Hurney, C A; Babcock, S K; Shook, D R; Pelletier, T M; Turner, S D; Maturo, J; Cogbill, S; Snow, M C; Kinch, K

    2015-05-01

    We present a complete staging table of normal development for the lungless salamander, Hemidactylium scutatum (Caudata: Plethodontidae). Terrestrial egg clutches from naturally ovipositing females were collected and maintained at 15 °C in the laboratory. Observations, photographs, and time-lapse movies of embryos were taken throughout the 45-day embryonic period. The complete normal table of development for H. scutatum is divided into 28 stages and extends previous analyses of H. scutatum embryonic development (Bishop, 1920; Humphrey, 1928). Early embryonic stage classifications through neurulation reflect criteria described for Xenopus laevis, Ambystoma maculatum and other salamanders. Later embryonic stage assignments are based on unique features of H. scutatum embryos. Additionally, we provide morphological analysis of gastrulation and neurulation, as well as details on external aspects of eye, gill, limb, pigmentation, and tail development to support future research related to phylogeny, comparative embryology, and molecular mechanisms of development.

  11. Programmed cell senescence during mammalian embryonic development.

    PubMed

    Muñoz-Espín, Daniel; Cañamero, Marta; Maraver, Antonio; Gómez-López, Gonzalo; Contreras, Julio; Murillo-Cuesta, Silvia; Rodríguez-Baeza, Alfonso; Varela-Nieto, Isabel; Ruberte, Jesús; Collado, Manuel; Serrano, Manuel

    2013-11-21

    Cellular senescence disables proliferation in damaged cells, and it is relevant for cancer and aging. Here, we show that senescence occurs during mammalian embryonic development at multiple locations, including the mesonephros and the endolymphatic sac of the inner ear, which we have analyzed in detail. Mechanistically, senescence in both structures is strictly dependent on p21, but independent of DNA damage, p53, or other cell-cycle inhibitors, and it is regulated by the TGF-β/SMAD and PI3K/FOXO pathways. Developmentally programmed senescence is followed by macrophage infiltration, clearance of senescent cells, and tissue remodeling. Loss of senescence due to the absence of p21 is partially compensated by apoptosis but still results in detectable developmental abnormalities. Importantly, the mesonephros and endolymphatic sac of human embryos also show evidence of senescence. We conclude that the role of developmentally programmed senescence is to promote tissue remodeling and propose that this is the evolutionary origin of damage-induced senescence. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. The embryonic development of frogs under strong DC magnetic fields

    SciTech Connect

    Ueno, S.; Harada, K.; Shiodawa, K.

    1984-09-01

    Possible influence of d.c. magnetic fields in the early embryonic development of frogs was studied. Embryos of African clawed toads, Xenopus laevis, were exposed to 1.0 T magnetic fields with different gradients of a range from 10 T/m to 10/sup 3/ T/m either during cleavage to neurula stage, blastula to neurula stage, or neurula to tail bud stage. The developmental processes of embryos during and after magnetic field exposures were followed to examine a possibility of teratogenic effects. The results suggest that the magnetic field exerts no harmful or modifying effects on the important morphogenetic movements such as gastrulation and neurulation. However, it was observed that embryos which were exposed to the gradient magnetic fields during cleavage to neurula stage occasionally developed into tadpoles with reduced pigmentation or some axial anomalies such as the formation of curled tail. Tadpoles with edema or microcephaly were also observed. Compared with the control, the rate of malformation was higher by about 35 %. The influence of oxygen concentration in Ringer's solution on the embryonic development was also studied, and toxicity of oxygen with high concentration is discussed.

  13. Characterization and embryonic expression of four amphioxus Frizzled genes with important functions during early embryogenesis.

    PubMed

    Qian, Guanghui; Li, Guang; Chen, Xiaoying; Wang, Yiquan

    2013-12-01

    The Wnt signaling pathway plays crucial roles in the embryonic patterning of all metazoans. Recent studies on Wnt genes in amphioxus have shed important insights into the evolution of the vertebrate Wnt gene family and their functions. Nevertheless, the potential roles of Wnt family receptors encoded by Frizzled (Fz) genes in amphioxus embryonic development remain to be investigated. In the present study, we identified four amphioxus Fz genes-AmphiFz1/2/7, AmphiFz4, AmphiFz5/8, and AmphiFz9/10-and analyzed their expression patterns during amphioxus embryogenesis. We found that these four Fz genes were maternally expressed and might be involved in early animal-vegetal axis establishment. The AmphiFz1/2/7 transcripts were detected in the central dorsal neural plate, mesoderm, the Hatschek's pit, and rim of the mouth, whereas those of AmphiFz4 were detected in the mesoderm, pharyngeal endoderm, and entire gut region. AmphiFz5/8 was exclusively expressed in the anterior-most region, whereas AmphiFz9/10 was expressed in the neural plate, somites, and tail bud. The dynamic and diverse expression patterns of amphioxus Fz genes suggest that these genes are not only associated with early embryonic axis establishment but also are involved in the development of several organs in amphioxus.

  14. Golgi Disruption and Early Embryonic Lethality in Mice Lacking USO1

    PubMed Central

    Kim, Susie; Hill, Adele; Warman, Matthew L.; Smits, Patrick

    2012-01-01

    Golgins are a family of long rod-like proteins characterized by the presence of central coiled-coil domains. Members of the golgin family have important roles in membrane trafficking, where they function as tethering factors that capture transport vesicles and facilitate membrane fusion. Golgin family members also have essential roles in maintaining the organization of the Golgi apparatus. Knockdown of individual golgins in cultured cells resulted in the disruption of the Golgi structure and the dispersal of Golgi marker proteins throughout the cytoplasm. However, these cellular phenotypes have not always been recapitulated in vivo. For example, embryonic development proceeds much further than expected and Golgi disruption was observed in only a subset of cell types in mice lacking the ubiquitously expressed golgin GMAP-210. Cell-type specific functional compensation among golgins may explain the absence of global cell lethality when a ubiquitously expressed golgin is missing. In this study we show that functional compensation does not occur for the golgin USO1. Mice lacking this ubiquitously expressed protein exhibit disruption of Golgi structure and early embryonic lethality, indicating that USO1 is indispensable for early embryonic development. PMID:23185636

  15. The effects of hemodynamic force on embryonic development

    PubMed Central

    CULVER, JAMES C.; DICKINSON, MARY E.

    2010-01-01

    Blood vessels have long been known to respond to hemodynamic force, and several mechanotransduction pathways have been identified. However, only recently have we begun to understand the effects of hemodynamic force on embryonic development. In this review, we will discuss specific examples illustrating the role of hemodynamic force during the development of the embryo, with particular focus on the development of the vascular system and the morphogenesis of the heart. We will also discuss the important functions served by mechanotransduction and hemodynamic force during placentation, as well as in regulating the maintenance and division of embryonic, hematopoietic, neural, and mesenchymal stem cells. Pathological misregulation of mechanosensitive pathways during pregnancy and embryonic development may contribute to the occurrence of cardiovascular birth defects, as well as to a variety of other diseases, including preeclampsia. Thus, there is a need for future studies focusing on better understanding the physiological effects of hemodynamic force during embryonic development and their role in the pathogenesis of disease. PMID:20374481

  16. Effects of dieldrin treatment on physiological and biochemical aspects of the toad embryonic development

    SciTech Connect

    Gauna, L.; Caballero de Castro, A.; Chifflet de Llamas, M.; Pechen de D'Angelo, A.M. )

    1991-04-01

    Dieldrin is a cylclodiene insecticide highly persistent in nature due to its chemical stability. The exposure of toad embryos to Dieldrin induces hyperactivity in the swimming larvae and inhibition of cholinesterases. However, the inhibition of these enzymes during early development is not life threatening. The present report provides a physiological and biochemical study of the noxious effect of Dieldrin on the toad embryonic development.

  17. Reelin expression during embryonic brain development in Crocodylus niloticus.

    PubMed

    Tissir, F; Lambert De Rouvroit, C; Sire, J-Y; Meyer, G; Goffinet, A M

    2003-03-10

    The expression of reelin mRNA and protein was studied during embryonic brain development in the Nile crocodile Crocodylus niloticus, using in situ hybridization and immunohistochemistry. In the forebrain, reelin was highly expressed in the olfactory bulb, septal nuclei, and subpial neurons in the marginal zone of the cerebral cortex, dorsal ventricular ridge, and basal forebrain. At early stages, reelin mRNA was also detected in subventricular zones. In the diencephalon, the ventral lateral geniculate nuclei and reticular nuclei were strongly positive, with moderate expression in the habenula and focal expression in the hypothalamus. High expression levels were noted in the retina, the tectum, and the external granule cell layer of the cerebellum. In the brainstem, there was a high level of signal in cochleovestibular, sensory trigeminal, and some reticular nuclei. No expression was observed in the cortical plate or Purkinje cells. Comparison with reelin expression during brain development in mammals, birds, turtles, and lizards reveals evolutionarily conserved, homologous features that presumably define the expression profile in stem amniotes. The crocodilian cortex contains subpial reelin-positive cells that are also p73 positive, suggesting that they are homologous to mammalian Cajal-Retzius cells, although they express the reelin gene less intensely. Furthermore, the crocodilian cortex does not contain the subcortical reelin-positive cells that are typical of lizards but expresses reelin in subventricular zones at early stages. These observations confirm that reelin is prominently expressed in many structures of the embryonic brain in all amniotes and further emphasize the unique amplification of reelin expression in mammalian Cajal-Retzius cells and its putative role in the evolution of the cerebral cortex. Copyright 2003 Wiley-Liss, Inc.

  18. A trade-off between embryonic development rate and immune function of avian offspring is concealed by embryonic temperature

    USGS Publications Warehouse

    Martin, Thomas E.; Arriero, Elena; Majewska, Ania

    2011-01-01

    Long embryonic periods are assumed to reflect slower intrinsic development that are thought to trade off to allow enhanced physiological systems, such as immune function. Yet, the relatively rare studies of this trade-off in avian offspring have not found the expected trade-off. Theory and tests have not taken into account the strong extrinsic effects of temperature on embryonic periods of birds. Here, we show that length of the embryonic period did not explain variation in two measures of immune function when temperature was ignored, based on studies of 34 Passerine species in tropical Venezuela (23 species) and north temperate Arizona (11 species). Variation in immune function was explained when embryonic periods were corrected for average embryonic temperature, in order to better estimate intrinsic rates of development. Immune function of offspring trades off with intrinsic rates of embryonic development once the extrinsic effects of embryonic temperatures are taken into account.

  19. Ornithine-δ-Aminotransferase Inhibits Neurogenesis During Xenopus Embryonic Development

    PubMed Central

    Peng, Ying; Cooper, Sandra K.; Li, Yi; Mei, Jay M.; Qiu, Shuwei; Borchert, Gregory L.; Donald, Steven P.; Kung, Hsiang-fu; Phang, James M.

    2015-01-01

    Purpose. In humans, deficiency of ornithine-δ-aminotransferase (OAT) results in progressive degeneration of the neural retina (gyrate atrophy) with blindness in the fourth decade. In this study, we used the Xenopus embryonic developmental model to study functions of the OAT gene on embryonic development. Methods. We cloned and sequenced full-length OAT cDNA from Xenopus oocytes (X-OAT) and determined X-OAT expression in various developmental stages of Xenopus embryos and in a variety of adult tissues. The phenotype, gene expression of neural developmental markers, and enzymatic activity were detected by gain-of-function and loss-of-function manipulations. Results. We showed that X-OAT is essential for Xenopus embryonic development, and overexpression of X-OAT produces a ventralized phenotype characterized by a small head, lack of axial structure, and defective expression of neural developmental markers. Using X-OAT mutants based on mutations identified in humans, we found that substitution of both Arg 180 and Leu 402 abrogated both X-OAT enzymatic activity and ability to modulate the developmental phenotype. Neurogenesis is inhibited by X-OAT during Xenopus embryonic development. Conclusions. Neurogenesis is inhibited by X-OAT during Xenopus embryonic development, but it is essential for Xenopus embryonic development. The Arg 180 and Leu 402 are crucial for these effects of the OAT molecule in development. PMID:25783604

  20. The embryonic development of the centipede Strigamia maritima.

    PubMed

    Brena, Carlo; Akam, Michael

    2012-03-01

    The geophilomorph centipede Strigamia maritima is an emerging model for studies of development and evolution among the myriapods. A draft genome sequence has recently been completed, making it also an important reference for comparative genomics, and for studies of myriapod physiology more generally. Here we present the first detailed description of myriapod development using modern techniques. We describe a timeline for embryonic development, with a detailed staging system based on photographs of live eggs and fixed embryos. We show that the early, cleavage and nuclear migration, stages of development are remarkably prolonged, accounting for nearly half of the total developmental period (approx 22 of 48 days at 13 °C). Towards the end of this period, cleavage cells migrate to the egg periphery to generate a uniform blastoderm. Asymmetry quickly becomes apparent as cells in the anterior half of the egg condense ventrally to form the presumptive head. Five anterior segments, the mandibular to the first leg-bearing segment (1st LBS) become clearly visible through the chorion almost simultaneously. Then, after a short pause, the next 35 leg-bearing segments appear at a uniform rate of 1 segment every 3.2 h (at 13 °C). Segment addition then slows to a halt with 40-45 LBS, shortly before the dramatic movements of germ band flexure, when the left and right halves of the embryo separate and the embryo folds deeply into the yolk. After flexure, segment morphogenesis and organogenesis proceed for a further 10 days, before the egg hatches. The last few leg-bearing segments are added during this period, much more slowly, at a rate of 1-2 segments/day. The last leg-bearing segment is fully defined only after apolysis of the embryonic cuticle, so that at hatching the embryo displays the final adult number of leg-bearing segments (typically 47-49 in our population).

  1. Embryonic requirements for ErbB signaling in neural crest development and adult pigment pattern formation

    PubMed Central

    Budi, Erine H.; Patterson, Larissa B.; Parichy, David M.

    2009-01-01

    SUMMARY Vertebrate pigment cells are derived from neural crest cells and are a useful system for studying neural crest-derived traits during post-embryonic development. In zebrafish, neural crest-derived melanophores differentiate during embryogenesis to produce stripes in the early larva. Dramatic changes to the pigment pattern occur subsequently during the larva-to-adult transformation, or metamorphosis. At this time, embryonic melanophores are replaced by newly differentiating metamorphic melanophores that form the adult stripes. Mutants with normal embryonic/early larval pigment patterns but defective adult patterns identify factors required uniquely to establish, maintain, or recruit the latent precursors to metamorphic melanophores. We show that one such mutant, picasso, lacks most metamorphic melanophores and results from mutations in the ErbB gene erbb3b, encoding an EGFR-like receptor tyrosine kinase. To identify critical periods for ErbB activities, we treated fish with pharmacological ErbB inhibitors and also knocked-down erbb3b by morpholino injection. These analyses reveal an embryonic critical period for ErbB signaling in promoting later pigment pattern metamorphosis, despite the normal patterning of embryonic/early larval melanophores. We further demonstrate a peak requirement during neural crest migration that correlates with early defects in neural crest pathfinding and peripheral ganglion formation. Finally, we show that erbb3b activities are both autonomous and non-autonomous to the metamorphic melanophore lineage. These data identify a very early, embryonic, requirement for erbb3b in the development of much later metamorphic melanophores, and suggest complex modes by which ErbB signals promote adult pigment pattern development. PMID:18508863

  2. Mouse early extra-embryonic lineages activate compensatory endocytosis in response to poor maternal nutrition.

    PubMed

    Sun, Congshan; Velazquez, Miguel A; Marfy-Smith, Stephanie; Sheth, Bhavwanti; Cox, Andy; Johnston, David A; Smyth, Neil; Fleming, Tom P

    2014-03-01

    Mammalian extra-embryonic lineages perform the crucial role of nutrient provision during gestation to support embryonic and fetal growth. These lineages derive from outer trophectoderm (TE) and internal primitive endoderm (PE) in the blastocyst and subsequently give rise to chorio-allantoic and visceral yolk sac placentae, respectively. We have shown maternal low protein diet exclusively during mouse preimplantation development (Emb-LPD) is sufficient to cause a compensatory increase in fetal and perinatal growth that correlates positively with increased adult-onset cardiovascular, metabolic and behavioural disease. Here, to investigate early mechanisms of compensatory nutrient provision, we assessed the influence of maternal Emb-LPD on endocytosis within extra-embryonic lineages using quantitative imaging and expression of markers and proteins involved. Blastocysts collected from Emb-LPD mothers within standard culture medium displayed enhanced TE endocytosis compared with embryos from control mothers with respect to the number and collective volume per cell of vesicles with endocytosed ligand and fluid and lysosomes, plus protein expression of megalin (Lrp2) LDL-family receptor. Endocytosis was also stimulated using similar criteria in the outer PE-like lineage of embryoid bodies formed from embryonic stem cell lines generated from Emb-LPD blastocysts. Using an in vitro model replicating the depleted amino acid (AA) composition found within the Emb-LPD uterine luminal fluid, we show TE endocytosis response is activated through reduced branched-chain AAs (leucine, isoleucine, valine). Moreover, activation appears mediated through RhoA GTPase signalling. Our data indicate early embryos regulate and stabilise endocytosis as a mechanism to compensate for poor maternal nutrient provision.

  3. Selection and dynamics of embryonic stem cell integration into early mouse embryos

    PubMed Central

    Alexandrova, Stoyana; Kalkan, Tuzer; Humphreys, Peter; Riddell, Andrew; Scognamiglio, Roberta; Trumpp, Andreas; Nichols, Jennifer

    2016-01-01

    The process by which pluripotent cells incorporate into host embryos is of interest to investigate cell potency and cell fate decisions. Previous studies suggest that only a minority of the embryonic stem cell (ESC) inoculum contributes to the adult chimaera. How incoming cells are chosen for integration or elimination remains unclear. By comparing a heterogeneous mix of undifferentiated and differentiating ESCs (serum/LIF) with more homogeneous undifferentiated culture (2i/LIF), we examine the role of cellular heterogeneity in this process. Time-lapse ex vivo imaging revealed a drastic elimination of serum/LIF ESCs during early development in comparison with 2i/LIF ESCs. Using a fluorescent reporter for naive pluripotency (Rex1-GFP), we established that the acutely eliminated serum/LIF ESCs had started to differentiate. The rejected cells were apparently killed by apoptosis. We conclude that a selection process exists by which unwanted differentiating cells are eliminated from the embryo. However, occasional Rex1− cells were able to integrate. Upregulation of Rex1 occurred in a proportion of these cells, reflecting the potential of the embryonic environment to expedite diversion from differentiation priming to enhance the developing embryonic epiblast. PMID:26586221

  4. GLUT3 gene expression is critical for embryonic growth, brain development and survival.

    PubMed

    Carayannopoulos, Mary O; Xiong, Fuxia; Jensen, Penny; Rios-Galdamez, Yesenia; Huang, Haigen; Lin, Shuo; Devaskar, Sherin U

    2014-04-01

    Glucose is the primary energy source for eukaryotic cells and the predominant substrate for the brain. GLUT3 is essential for trans-placental glucose transport and highly expressed in the mammalian brain. To further elucidate the role of GLUT3 in embryonic development, we utilized the vertebrate whole animal model system of Danio rerio as a tractable system for defining the cellular and molecular mechanisms altered by impaired glucose transport and metabolism related to perturbed expression of GLUT3. The comparable orthologue of human GLUT3 was identified and the expression of this gene abrogated during early embryonic development. In a dose-dependent manner embryonic brain development was disrupted resulting in a phenotype of aberrant brain organogenesis, associated with embryonic growth restriction and increased cellular apoptosis. Rescue of the morphant phenotype was achieved by providing exogenous GLUT3 mRNA. We conclude that GLUT3 is critically important for brain organogenesis and embryonic growth. Disruption of GLUT3 is responsible for the phenotypic spectrum of embryonic growth restriction to demise and neural apoptosis with microcephaly. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Shh expression is required for embryonic hair follicle but not mammary gland development.

    PubMed

    Michno, Kinga; Boras-Granic, Kata; Mill, Pleasantine; Hui, C C; Hamel, Paul A

    2003-12-01

    The embryonic mammary gland and hair follicle are both derived from the ventral ectoderm, and their development depends on a number of common fundamental developmental pathways. While the Hedgehog (Hh) signaling pathway is required for hair follicle morphogenesis, the role of this pathway during embryonic mammary gland development remains undetermined. We demonstrate here that, unlike the hair follicle, both Shh and Ihh are expressed in the developing embryonic mouse mammary rudiment as early as E12.5. In Shh(-/-) embryos, hair follicle development becomes arrested at an early stage, while the mammary rudiment, which continues to express Ihh, develops in a manner indistinguishable from that of wild-type littermates. The five pairs of mammary buds in Shh(-/-) female embryos exhibit normal branching morphogenesis at E16.5, forming a rudimentary ductal structure identical to wild-type embryonic mammary glands. We further demonstrate that loss of Hh signaling causes altered cyclin D1 expression in the embryonic dermal mesenchyme. Specifically, cyclin D1 is expressed at E14.5 principally in the condensed mesenchymal cells of the presumptive hair follicles and in both mesenchymal and epithelial cells of the mammary rudiments in wild-type and Shh-deficient embryos. By E18.5, robust cyclin D1 expression is maintained in mammary rudiments of both wild-type and Shh-deficient embryos. In hair follicles of wild-type embryos by E18.5, cyclin D1 expression switches to follicular epithelial cells. In contrast, strong cyclin D1 expression is observed principally in the mesenchymal cells of arrested hair follicles in Shh(-/-) embryos at E18.5. These data reveal that, despite the common embryonic origin of hair follicles and mammary glands, distinct patterns of Hh-family expression occur in these two tissues. Furthermore, these data suggest that cyclin D1 expression in the embryonic hair follicle is mediated by both Hh-independent and Hh-dependent mechanisms.

  6. Genome wide identification of promoter binding sites for H4K12ac in human sperm and its relevance for early embryonic development

    PubMed Central

    Paradowska, Agnieszka S.; Miller, David; Spiess, Andrej-Nikolai; Vieweg, Markus; Cerna, Martina; Dvorakova-Hortova, Katerina; Bartkuhn, Marek; Schuppe, Hans-Christian; Weidner, Wolfgang; Steger, Klaus

    2012-01-01

    Sperm chromatin reveals two characteristic features in that protamines are the predominant nuclear proteins and remaining histones are highly acetylated. Histone H4 acetylated at lysine 12 (H4K12ac) is localized in the post-acrosomal region, while protamine-1 is present within the whole nucleus. Chromatin immunoprecipitation in combination with promoter array analysis allowed genome-wide identification of H4K12ac binding sites. Previously, we reported enrichment of H4K12ac at CTCF binding sites and promoters of genes involved in developmental processes. Here, we demonstrate that H4K12ac is enriched predominantly between ± 2 kb from the transcription start site. In addition, we identified developmentally relevant H4K12ac-associated promoters with high expression levels of their transcripts stored in mature sperm. The highest expressed mRNA codes for testis-specific PHD finger protein-7 (PHF7), suggesting an activating role of H4K12ac in the regulatory elements of this gene. H4K12ac-associated genes revealed a weak correlation with genes expressed at 4-cell stage human embryos, while 23 H4K12ac-associated genes were activated in 8-cell embryo and 39 in the blastocyst. Genes activated in 4-cell embryos are involved in gene expression, histone fold and DNA-dependent transcription, while genes expressed in the blastocyst were classified as involved in developmental processes. Immunofluorescence staining detected H4K12ac from the murine male pronucleus to early stages of embryogenesis. Aberrant histone acetylation within developmentally important gene promoters in infertile men may reflect insufficient sperm chromatin compaction, which may result in inappropriate transfer of epigenetic information to the oocyte. PMID:22894908

  7. Bioenergetic Profiling of Zebrafish Embryonic Development

    PubMed Central

    Stackley, Krista D.; Beeson, Craig C.; Rahn, Jennifer J.; Chan, Sherine S. L.

    2011-01-01

    Many debilitating conditions are linked to bioenergetic defects. Developing screens to probe the genetic and/or chemical basis for such links has proved intractable. Furthermore, there is a need for a physiologically relevant assay of bioenergetics in whole organisms, especially for early stages in life where perturbations could increase disease susceptibility with aging. Thus, we asked whether we could screen bioenergetics and mitochondrial function in the developing zebrafish embryo. We present a multiplexed method to assay bioenergetics in zebrafish embryos from the blastula period (3 hours post-fertilization, hpf) through to hatching (48 hpf). In proof of principle experiments, we measured respiration and acid extrusion of developing zebrafish embryos. We quantified respiratory coupling to various bioenergetic functions by using specific pharmacological inhibitors of bioenergetic pathways. We demonstrate that changes in the coupling to ATP turnover and proton leak are correlated with developmental stage. The multiwell format of this assay enables the user to screen for the effects of drugs and environmental agents on bioenergetics in the zebrafish embryo with high sensitivity and reproducibility. PMID:21980518

  8. High-Frequency Ultrasound for the Study of Early Mouse Embryonic Cardiovascular System.

    PubMed

    Greco, Adelaide; Coda, Anna Rita Daniela; Albanese, Sandra; Ragucci, Monica; Liuzzi, Raffaele; Auletta, Luigi; Gargiulo, Sara; Lamagna, Francesco; Salvatore, Marco; Mancini, Marcello

    2015-12-01

    An accurate diagnosis of congenital heart defects during fetal development is critical for interventional planning. Mice can be used to generate animal models with heart defects, and high-frequency ultrasound (HFUS) imaging enables in utero imaging of live mouse embryos. A wide range of physiological measurements is possible using Doppler-HFUS imaging; limitations of any single measurement warrant a multiparameter approach to characterize cardiovascular function. Doppler-HFUS was used to explore the embryonic (heart, aorta) and extraembryonic (umbilical blood flow) circulatory systems to create a database in normal mouse embryos between 9.5 and 16.5 days of gestation. Multivariate analyses were performed to explore correlations between gestational age and embryo echocardiographic parameters. Heart rate and peak velocity in the aorta were positively correlated with gestational time, whereas cardiac cycle length, isovolumetric relaxation time, myocardial performance index, and arterial deceleration time of the umbilical cord were negatively correlated with it. Doppler-HFUS facilitated detailed characterization of the embryonic mouse circulation and represents a useful tool for investigation of the early mouse embryonic cardiovascular system. © The Author(s) 2015.

  9. A cohesin–OCT4 complex mediates Sox enhancers to prime an early embryonic lineage

    PubMed Central

    Abboud, Nesrine; Moore-Morris, Thomas; Hiriart, Emilye; Yang, Henry; Bezerra, Hudson; Gualazzi, Maria-Giovanna; Stefanovic, Sonia; Guénantin, Anne-Claire; Evans, Sylvia M.; Pucéat, Michel

    2017-01-01

    Short- and long-scales intra-and inter-chromosomal interactions are linked to gene transcription, but the molecular events underlying these structures and how they affect cell fate decision during embryonic development are poorly understood. One of the first embryonic cell fate decisions (that is, mesendoderm determination) is driven by the POU factor OCT4, acting in concert with the high-mobility group genes Sox-2 and Sox-17. Here we report a chromatin-remodelling mechanism and enhancer function that mediate cell fate switching. OCT4 alters the higher-order chromatin structure at both Sox-2 and Sox-17 loci. OCT4 titrates out cohesin and switches the Sox-17 enhancer from a locked (within an interchromosomal Sox-2 enhancer/CCCTC-binding factor CTCF/cohesin loop) to an active (within an intra-chromosomal Sox-17 promoter/enhancer/cohesin loop) state. SALL4 concomitantly mobilizes the polycomb complexes at the Soxs loci. Thus, OCT4/SALL4-driven cohesin- and polycombs-mediated changes in higher-order chromatin structure mediate instruction of early cell fate in embryonic cells. PMID:25851587

  10. In vivo effect of interleukin-1beta and interleukin-1RA on oocyte cytoplasmic maturation, ovulation, and early embryonic development in the mare

    PubMed Central

    Caillaud, Maud; Duchamp, Guy; Gérard, Nadine

    2005-01-01

    A growing body of evidence suggests that the interleukin-1 system is involved in periovulatory events. Previous work from our lab demonstrated that in the mare, interleukin-1beta (IL-1beta) increases the ovulatory rate of metaphase II oocytes. The present study was conducted to analyze in vivo the effect of IL-1 on oocyte cytoplasmic maturation, ovulation and pregnancy rate. In the present work, IL-1beta (experiment 1, n = 13; experiment 2, n = 25) and interleukin-1RA (IL-1RA; experiment 1, n = 25) were injected intrafollicularly by using the transvaginal ultrasound-guided injection method. Injections were performed on cyclic mares when the diameter of the growing dominant follicle reached 30–34 mm. In experiment 1, mares were inseminated the day of the treatment and all the other day until ovulation. The time of ovulation was determined and a pregnancy diagnosis was performed 14 days after ovulation of the injected follicle. In experiment 2, the cumulus-oocyte complex from each injected follicle was collected by transvaginal ultrasound-guided aspiration 38 h after the intrafollicular injection. Oocyte nuclear stage and oocyte cytoplasmic maturation were assessed by analyzing chromatin configuration, cortical granules migration and mitochondria distribution under a confocal microscope. The results from experiment 1 confirm that an intrafollicular injection of 1 microgram IL-1beta induces ovulation in the mare whereas IL-1RA has no effect at the dose used in the present study. Furthemore, we demonstrated, that in our experimental conditions, IL-1beta and IL-1RA induced a decrease in embryo development. Experiment 2 leads us to observe that IL-1beta is unable to induce cortical granules migration and remodelling of mitochondria, that commonly occurs during oocyte maturation, whereas it acts on nuclear maturation. This result may explain the decrease in embryo development we observed after IL-1beta intrafollicular injection. In conclusion, the present study tends to

  11. Description of embryonic development of spotted green pufferfish (Tetraodon nigroviridis).

    PubMed

    Zaucker, Andreas; Bodur, Türker; Roest Crollius, Hugues; Hadzhiev, Yavor; Gehrig, Jochen; Loosli, Felix; Watson, Craig; Müller, Ferenc

    2014-12-01

    Pufferfish species of the Tetraodontidae family carry the smallest genomes among vertebrates. Their compressed genomes are thought to be enriched for functional DNA compared to larger vertebrate genomes, and they are important models for comparative genomics. The significance of pufferfish as model organisms in comparative genomics is due to the availability of two sequenced genomes, that of spotted green pufferfish (Tetraodon nigroviridis) and fugu (Takifugu rubripes). However, there is only a very limited utilization of pufferfish as an experimental model organism, due to the lack of established husbandry and developmental genetics protocols. In this study, we provide the first description of the normal embryonic development of Tetraodon nigroviridis. Embryos were obtained by in vitro fertilization of eggs, and subsequent development was monitored by brightfield microscopy at constant temperature. Tetraodon development was divided into distinct stages based on diagnostic morphological features, which were adopted from published literature on normal development of other fish species like medaka (Oryzias latipes), zebrafish (Danio rerio), and fugu. Tetraodon embryos show more similar morphologies to medaka than to zebrafish, reflecting its phylogenetic position. The early developmental stage series described in this study forms the foundation for the utilization of tetraodon as an experimental model organism for comparative developmental studies.

  12. Description of Embryonic Development of Spotted Green Pufferfish (Tetraodon nigroviridis)

    PubMed Central

    Zaucker, Andreas; Bodur, Türker; Roest Crollius, Hugues; Hadzhiev, Yavor; Gehrig, Jochen; Loosli, Felix; Watson, Craig

    2014-01-01

    Abstract Pufferfish species of the Tetraodontidae family carry the smallest genomes among vertebrates. Their compressed genomes are thought to be enriched for functional DNA compared to larger vertebrate genomes, and they are important models for comparative genomics. The significance of pufferfish as model organisms in comparative genomics is due to the availability of two sequenced genomes, that of spotted green pufferfish (Tetraodon nigroviridis) and fugu (Takifugu rubripes). However, there is only a very limited utilization of pufferfish as an experimental model organism, due to the lack of established husbandry and developmental genetics protocols. In this study, we provide the first description of the normal embryonic development of Tetraodon nigroviridis. Embryos were obtained by in vitro fertilization of eggs, and subsequent development was monitored by brightfield microscopy at constant temperature. Tetraodon development was divided into distinct stages based on diagnostic morphological features, which were adopted from published literature on normal development of other fish species like medaka (Oryzias latipes), zebrafish (Danio rerio), and fugu. Tetraodon embryos show more similar morphologies to medaka than to zebrafish, reflecting its phylogenetic position. The early developmental stage series described in this study forms the foundation for the utilization of tetraodon as an experimental model organism for comparative developmental studies. PMID:25243591

  13. Expression Pattern of Inflammatory Response Genes and Their Regulatory MicroRNAs in Bovine Oviductal Cells in Response to Lipopolysaccharide: Implication for Early Embryonic Development

    PubMed Central

    Ibrahim, Sally; Salilew-Wondim, Dessie; Rings, Franca; Hoelker, Michael; Neuhoff, Christiane; Tholen, Ernst; Looft, Christian; Schellander, Karl; Tesfaye, Dawit

    2015-01-01

    In the present study, we used an in vitro model to investigate the response of the oviduct with respect to inflammatory mediators and their regulatory microRNAs in case of bacterial infection and subsequent association with embryo survival. For this, we conducted two experiments. In the first experiment, cultured primary bovine oviductal cells (BOEC) were challenged with lipopolysaccharide (LPS) for 24h and the temporal expression pattern of inflammatory mediators and their regulatory microRNAs were measured at 0, 3, 6, 12, 24 and 48h after LPS treatment. Intriguingly, the temporal patterns of all miRNAs except miR-21 were significantly up-regulated at 6h after LPS treatment. Whereas, we observed significant overexpression of pro-inflammatory mediators as tumor necrosis factor alpha (TNFα) and interleukin-1 beta (IL1β) after LPS challenge for 24h. On the other hand, the expression level of essential elements like oviductal glycoprotein 1 (OVGP1) and insulin-like growth factor 2 (IGF2) was significantly decreased in challenged groups compared with control. Moreover, miR-155, miR-146a, miR-223, miR-21, miR-16 and miR-215 have shown a clear suppression in challenged group after LPS treatment. In the 2nd experiment there were four groups of blastocysts produced, namely embryo+LPS free media, embryo+LPS, BOEC+embryo and BOEC+embryo+LPS. The suboptimal oviduct environment due to LPS challenge is found to have a significant influence on the expression of inflammatory response genes (TNFα and CSF1), stress response genes (SOD and CAT), mitochondrial activity, reactive oxygen species (ROS) accumulation and apoptotic level either in cultured or co-cultured blastocysts. Collectively, LPS challenge led to aberrant changes in oviductal transcriptome profile, which could lead to a suboptimal environment for embryo development. PMID:25764515

  14. Mechanistic Target of Rapamycin (Mtor) Is Essential for Murine Embryonic Heart Development and Growth

    PubMed Central

    Zhu, Yi; Pires, Karla M. P.; Whitehead, Kevin J.; Olsen, Curtis D.; Wayment, Benjamin; Zhang, Yi Cheng; Bugger, Heiko; Ilkun, Olesya; Litwin, Sheldon E.; Thomas, George; Kozma, Sara C.; Abel, E. Dale

    2013-01-01

    Mechanistic target of rapamycin (Mtor) is required for embryonic inner cell mass proliferation during early development. However, Mtor expression levels are very low in the mouse heart during embryogenesis. To determine if Mtor plays a role during mouse cardiac development, cardiomyocyte specific Mtor deletion was achieved using α myosin heavy chain (α-MHC) driven Cre recombinase. Initial mosaic expression of Cre between embryonic day (E) 10.5 and E11.5 eliminated a subset of cardiomyocytes with high Cre activity by apoptosis and reduced overall cardiac proliferative capacity. The remaining cardiomyocytes proliferated and expanded normally. However loss of 50% of cardiomyocytes defined a threshold that impairs the ability of the embryonic heart to sustain the embryo’s circulatory requirements. As a result 92% of embryos with cardiomyocyte Mtor deficiency died by the end of gestation. Thus Mtor is required for survival and proliferation of cardiomyocytes in the developing heart. PMID:23342106

  15. Microfluidic-based patterning of embryonic stem cells for in vitro development studies.

    PubMed

    Suri, Shalu; Singh, Ankur; Nguyen, Anh H; Bratt-Leal, Andres M; McDevitt, Todd C; Lu, Hang

    2013-12-07

    In vitro recapitulation of mammalian embryogenesis and examination of the emerging behaviours of embryonic structures require both the means to engineer complexity and accurately assess phenotypes of multicellular aggregates. Current approaches to study multicellular populations in 3D configurations are limited by the inability to create complex (i.e. spatially heterogeneous) environments in a reproducible manner with high fidelity thus impeding the ability to engineer microenvironments and combinations of cells with similar complexity to that found during morphogenic processes such as development, remodelling and wound healing. Here, we develop a multicellular embryoid body (EB) fusion technique as a higher-throughput in vitro tool, compared to a manual assembly, to generate developmentally relevant embryonic patterns. We describe the physical principles of the EB fusion microfluidic device design; we demonstrate that >60 conjoined EBs can be generated overnight and emulate a development process analogous to mouse gastrulation during early embryogenesis. Using temporal delivery of bone morphogenic protein 4 (BMP4) to embryoid bodies, we recapitulate embryonic day 6.5 (E6.5) during mouse embryo development with induced mesoderm differentiation in murine embryonic stem cells leading to expression of Brachyury-T-green fluorescent protein (T-GFP), an indicator of primitive streak development and mesoderm differentiation during gastrulation. The proposed microfluidic approach could be used to manipulate hundreds or more of individual embryonic cell aggregates in a rapid fashion, thereby allowing controlled differentiation patterns in fused multicellular assemblies to generate complex yet spatially controlled microenvironments.

  16. Microfluidic-based patterning of embryonic stem cells for in vitro development studies

    PubMed Central

    Suri, Shalu; Singh, Ankur; Nguyen, Anh H.; Bratt-Leal, Andres M.; McDevitt, Todd C.

    2013-01-01

    In vitro recapitulation of mammalian embryogenesis and examination of the emerging behaviours of embryonic structures require both the means to engineer complexity and accurately assess phenotypes of multicellular aggregates. Current approaches to study multicellular populations in 3D configurations are limited by the inability to create complex (i.e. spatially heterogeneous) environments in a reproducible manner with high fidelity thus impeding the ability to engineer microenvironments and combinations of cells with similar complexity to that found during morphogenic processes such as development, remodelling and wound healing. Here, we develop a multicellular embryoid body (EB) fusion technique as a higher-throughput in vitro tool, compared to a manual assembly, to generate developmentally relevant embryonic patterns. We describe the physical principles of the EB fusion microfluidic device design; we demonstrate that >60 conjoined EBs can be generated overnight and emulate a development process analogous to mouse gastrulation during early embryogenesis. Using temporal delivery of bone morphogenic protein 4 (BMP4) to embryoid bodies, we recapitulate embryonic day 6.5 (E6.5) during mouse embryo development with induced mesoderm differentiation in murine embryonic stem cells leading to expression of Brachyury-T-green fluorescent protein (T-GFP), an indicator of primitive streak development and mesoderm differentiation during gastrulation. The proposed microfluidic approach could be used to manipulate hundreds or more of individual embryonic cell aggregates in a rapid fashion, thereby allowing controlled differentiation patterns in fused multicellular assemblies to generate complex yet spatially controlled microenvironments. PMID:24113509

  17. [Teratogenesis and gene targets of 17alpha-ethynylestradiol on embryonic development in zebrafish].

    PubMed

    Tong, Jun-Wei; Zhang, Jing-Pu; Meng, Jie

    2011-01-01

    The pharmaceutical ethynylestradiol (EE) is a potent endocrine modulator. Application enlargement of ethynylestradiol in clinics and abuse in livestock farming and fishing make it important to explore ethynylestradiol toxicological action on vertebrate embryonic development and to establish an in vivo method for EE toxicity detection efficiently and conveniently. In the present study, using a model animal zebrafish and 17alpha-ethynylestradiol as a representative compound, we have investigated EE2 teratogenicity, target tissues and target genes on zebrafish embryo. The results show that median teratogenesis concentration (TC50) of EE2 is 0.8 microg x mL(-1), and median lethal dose (LD50) is 3.3 microg x mL(-1). Targets of EE2 action were implicated in brain, eyes, heart, muscle, skeleton, pigment and viscera. Embryonic cardiac arrhythmia caused by EE2 is probably resulted from heart abnormal structure. The embryonic stage sensitive to EE2 mainly started at cleavage and last up to the organogenesis with time-accumulating effect. RT-PCR results indicate that EE2 treatment disturbed gene expression pattern at the early period of zebrafish embryonic development by suppressing transcription of gene boz that promotes brain development, upregulating genes for trunk and tail, such as ntl, spt, shh, and perturbing Nodal signal expression of TGFbeta superfamily, for example, cyc, sqt and oep. Using zebrafish, an efficient in vivo method for quick evaluation of EE toxicity on embryonic development has been developed.

  18. SSAO/VAP-1 protein expression during mouse embryonic development.

    PubMed

    Valente, Tony; Solé, Montse; Unzeta, Mercedes

    2008-09-01

    SSAO/VAP-1 is a multifunctional enzyme depending on in which tissue it is expressed. SSAO/VAP-1 is present in almost all adult mammalian tissues, especially in highly vascularised ones and in adipocytes. SSAO/VAP-1 is an amine oxidase able to metabolise various endogenous or exogenous primary amines. Its catalytic activity can lead to cellular oxidative stress, which has been implicated in several pathologies (atherosclerosis, diabetes, and Alzheimer's disease). The aim of this work is to achieve a study of SSAO/VAP-1 protein expression during mouse embryogenesis. Our results show that SSAO/VAP-1 appears early in the development of the vascular system, adipose tissue, and smooth muscle cells. Moreover, its expression is strong in several epithelia of the sensory organs, as well as in the development of cartilage sites. Altogether, this suggests that SSAO/VAP-1 enzyme could be involved in the differentiation processes that take place during embryonic development, concretely in tissue vascularisation.

  19. Regulation of the Embryonic Cell Cycle During Mammalian Preimplantation Development.

    PubMed

    Palmer, N; Kaldis, P

    2016-01-01

    The preimplantation development stage of mammalian embryogenesis consists of a series of highly conserved, regulated, and predictable cell divisions. This process is essential to allow the rapid expansion and differentiation of a single-cell zygote into a multicellular blastocyst containing cells of multiple developmental lineages. This period of development, also known as the germinal stage, encompasses several important developmental transitions, which are accompanied by dramatic changes in cell cycle profiles and dynamics. These changes are driven primarily by differences in the establishment and enforcement of cell cycle checkpoints, which must be bypassed to facilitate the completion of essential cell cycle events. Much of the current knowledge in this area has been amassed through the study of knockout models in mice. These mouse models are powerful experimental tools, which have allowed us to dissect the relative dependence of the early embryonic cell cycles on various aspects of the cell cycle machinery and highlight the extent of functional redundancy between members of the same gene family. This chapter will explore the ways in which the cell cycle machinery, their accessory proteins, and their stimuli operate during mammalian preimplantation using mouse models as a reference and how this allows for the usually well-defined stages of the cell cycle to be shaped and transformed during this unique and critical stage of development. © 2016 Elsevier Inc. All rights reserved.

  20. The ‘Ventral Organs’ of Pycnogonida (Arthropoda) Are Neurogenic Niches of Late Embryonic and Post-Embryonic Nervous System Development

    PubMed Central

    Brenneis, Georg; Scholtz, Gerhard

    2014-01-01

    Early neurogenesis in arthropods has been in the focus of numerous studies, its cellular basis, spatio-temporal dynamics and underlying genetic network being by now comparably well characterized for representatives of chelicerates, myriapods, hexapods and crustaceans. By contrast, neurogenesis during late embryonic and/or post-embryonic development has received less attention, especially in myriapods and chelicerates. Here, we apply (i) immunolabeling, (ii) histology and (iii) scanning electron microscopy to study post-embryonic ventral nerve cord development in Pseudopallene sp., a representative of the sea spiders (Pycnogonida), the presumable sister group of the remaining chelicerates. During early post-embryonic development, large neural stem cells give rise to additional ganglion cell material in segmentally paired invaginations in the ventral ectoderm. These ectodermal cell regions – traditionally designated as ‘ventral organs’ – detach from the surface into the interior and persist as apical cell clusters on the ventral ganglion side. Each cluster is a post-embryonic neurogenic niche that features a tiny central cavity and initially still houses larger neural stem cells. The cluster stays connected to the underlying ganglionic somata cortex via an anterior and a posterior cell stream. Cell proliferation remains restricted to the cluster and streams, and migration of newly produced cells along the streams seems to account for increasing ganglion cell numbers in the cortex. The pycnogonid cluster-stream-systems show striking similarities to the life-long neurogenic system of decapod crustaceans, and due to their close vicinity to glomerulus-like neuropils, we consider their possible involvement in post-embryonic (perhaps even adult) replenishment of olfactory neurons – as in decapods. An instance of a potentially similar post-embryonic/adult neurogenic system in the arthropod outgroup Onychophora is discussed. Additionally, we document two transient

  1. Embryonic development of Girardia tigrina (Girard, 1850) (Platyhelminthes, Tricladida, Paludicola).

    PubMed

    Vara, D C; Leal-Zanchet, A M; Lizardo-Daudt, H m

    2008-11-01

    The embryonic development of freshwater triclads is mainly known from studies of species of Dendrocoelum, Planaria, Polycelis, and, more recently, Schmidtea. The present study characterizes the development of Girardia tigrina (Girard, 1850) by means of optical microcopy using glycol methacrylate semi-thin sections. 94 cocoons were collected in the period from laying to hatching, with intervals of up to twenty-four hours. The sequence of morphological changes occurring in the embryo permitted the identification of nine embryonic stages. At the time of cocoon laying, numerous embryos were dispersed among many yolk cells, with a rigid capsule covering the entire cocoon. In the first stage (approx. up to 6 hours after cocoon laying), yolk cells and embryonic cells showed random distribution. Stage II (between 12 and 24 hours after cocoon laying) is characterized by aggregates of blastomeres, which later aggregate forming an enteroblastula. Approximately 2 days after cocoon laying (stage III), formation of the embryonic epidermis and embryonic digestive system took place, the latter degenerating during the subsequent stage. Stage V (until the fourth day) is characterized by the formation of the definitive epidermis. Between 4 and 6 days after laying, organogenesis of the definitive inner organs starts (stage VI). Approximately 14 days after laying (stage IX), formation of the nervous system is completed. At this stage, the embryo shows similar characteristics to those of newly hatched juveniles. The hatching of Girardia tigrina occurs in the period between twelve to twenty-two days after cocoon laying.

  2. Functional analysis of Scr during embryonic and post-embryonic development in the cockroach, Periplaneta americana.

    PubMed

    Hrycaj, Steven; Chesebro, John; Popadić, Aleksandar

    2010-05-01

    The cockroach, Periplaneta americana represents a basal insect lineage that undergoes the ancestral hemimetabolous mode of development. Here, we examine the embryonic and post-embryonic functions of the hox gene Scr in Periplaneta as a way of better understanding the roles of this gene in the evolution of insect body plans. During embryogenesis, Scr function is strictly limited to the head with no role in the prothorax. This indicates that the ancestral embryonic function of Scr was likely restricted to the head, and that the posterior expansion of expression in the T1 legs may have preceded any apparent gain of function during evolution. In addition, Scr plays a pivotal role in the formation of the dorsal ridge, a structure that separates the head and thorax in all insects. This is evidenced by the presence of a supernumerary segment that occurs between the labial and T1 segments of RNAiScr first nymphs and is attributed to an alteration in engrailed (en) expression. The fact that similar Scr phenotypes are observed in Tribolium but not in Drosophila or Oncopeltus reveals the presence of lineage-specific variation in the genetic architecture that controls the formation of the dorsal ridge. In direct contrast to the embryonic roles, Scr has no function in the head region during post-embryogenesis in Periplaneta, and instead, strictly acts to provide identity to the T1 segment. Furthermore, the strongest Periplaneta RNAiScr phenotypes develop ectopic wing-like tissue that originates from the posterior region of the prothoracic segment. This finding provides a novel insight into the current debate on the morphological origin of insect wings.

  3. Manipulation and in vitro maturation of Xenopus laevis oocytes, followed by intracytoplasmic sperm injection, to study embryonic development.

    PubMed

    Miyamoto, Kei; Simpson, David; Gurdon, John B

    2015-02-09

    Amphibian eggs have been widely used to study embryonic development. Early embryonic development is driven by maternally stored factors accumulated during oogenesis. In order to study roles of such maternal factors in early embryonic development, it is desirable to manipulate their functions from the very beginning of embryonic development. Conventional ways of gene interference are achieved by injection of antisense oligonucleotides (oligos) or mRNA into fertilized eggs, enabling under- or over-expression of specific proteins, respectively. However, these methods normally require more than several hours until protein expression is affected, and, hence, the interference of gene functions is not effective during early embryonic stages. Here, we introduce an experimental system in which expression levels of maternal proteins can be altered before fertilization. Xenopus laevis oocytes obtained from ovaries are defolliculated by incubating with enzymes. Antisense oligos or mRNAs are injected into defolliculated oocytes at the germinal vesicle (GV) stage. These oocytes are in vitro matured to eggs at the metaphase II (MII) stage, followed by intracytoplasmic sperm injection (ICSI). By this way, up to 10% of ICSI embryos can reach the swimming tadpole stage, thus allowing functional tests of specific gene knockdown or overexpression. This approach can be a useful way to study roles of maternally stored factors in early embryonic development.

  4. Polycomb function during oogenesis is required for mouse embryonic development

    PubMed Central

    Posfai, Eszter; Kunzmann, Rico; Brochard, Vincent; Salvaing, Juliette; Cabuy, Erik; Roloff, Tim C.; Liu, Zichuan; Tardat, Mathieu; van Lohuizen, Maarten; Vidal, Miguel; Beaujean, Nathalie; Peters, Antoine H.F.M.

    2012-01-01

    In mammals, totipotent embryos are formed by fusion of highly differentiated gametes. Acquisition of totipotency concurs with chromatin remodeling of parental genomes, changes in the maternal transcriptome and proteome, and zygotic genome activation (ZGA). The inefficiency of reprogramming somatic nuclei in reproductive cloning suggests that intergenerational inheritance of germline chromatin contributes to developmental proficiency after natural conception. Here we show that Ring1 and Rnf2, components of Polycomb-repressive complex 1 (PRC1), serve redundant transcriptional functions during oogenesis that are essential for proper ZGA, replication and cell cycle progression in early embryos, and development beyond the two-cell stage. Exchange of chromosomes between control and Ring1/Rnf2-deficient metaphase II oocytes reveal cytoplasmic and chromosome-based contributions by PRC1 to embryonic development. Our results strongly support a model in which Polycomb acts in the female germline to establish developmental competence for the following generation by silencing differentiation-inducing genes and defining appropriate chromatin states. PMID:22499591

  5. Comparisons of embryonic development in Drosophila, Nasonia, and Tribolium

    PubMed Central

    Brown, Susan J.

    2017-01-01

    Studying the embryogenesis of diverse insect species is crucial to understanding insect evolution. Here we review current advances in understanding the development of two emerging model organisms: the wasp Nasonia vitripennis, and the beetle Tribolium castaneum in comparison to the well-studied fruit fly Drosophila melanogaster. Although Nasonia represents the most basally branching order of holometabolous insects, it employs a derived long germband mode of embryogenesis, more like that of Drosophila, while Tribolium undergoes an intermediate germband mode of embryogenesis, which is more similar to the ancestral mechanism. Comparing the embryonic development and genetic regulation of early patterning events in these three insects has given invaluable insights into insect evolution. The similar mode of embryogenesis of Drosophila and Nasonia is reflected in their reliance on maternal morphogenetic gradients. However, they employ different genes as maternal factors, reflecting the evolutionary distance separating them. Tribolium on the other hand relies heavily on self-regulatory mechanisms other than maternal cues, reflecting its sequential nature of segmentation and the need for reiterated patterning. PMID:23801665

  6. Comparisons of the embryonic development of Drosophila, Nasonia, and Tribolium.

    PubMed

    Lynch, Jeremy A; El-Sherif, Ezzat; Brown, Susan J

    2012-01-01

    Studying the embryogenesis of diverse insect species is crucial to understanding insect evolution. Here, we review current advances in understanding the development of two emerging model organisms: the wasp Nasonia vitripennis and the beetle Tribolium castaneum in comparison with the well-studied fruit fly Drosophila melanogaster. Although Nasonia represents the most basally branching order of holometabolous insects, it employs a derived long germband mode of embryogenesis, more like that of Drosophila, whereas Tribolium undergoes an intermediate germband mode of embryogenesis, which is more similar to the ancestral mechanism. Comparing the embryonic development and genetic regulation of early patterning events in these three insects has given invaluable insights into insect evolution. The similar mode of embryogenesis of Drosophila and Nasonia is reflected in their reliance on maternal morphogenetic gradients. However, they employ different genes as maternal factors, reflecting the evolutionary distance separating them. Tribolium, on the other hand, relies heavily on self-regulatory mechanisms other than maternal cues, reflecting its sequential nature of segmentation and the need for reiterated patterning.

  7. Embryonic Exposure to the Environmental Neurotoxin BMAA Negatively Impacts Early Neuronal Development and Progression of Neurodegeneration in the Sod1-G93R Zebrafish Model of Amyotrophic Lateral Sclerosis.

    PubMed

    Powers, Samantha; Kwok, Samantha; Lovejoy, Emily; Lavin, Tom; Sher, Roger

    2017-01-25

    Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disorder leading to progressive paralysis and death within 2-5 years after diagnosis. Sporadic cases (SALS) comprise ∼90% of cases with the remaining 10% familial (FALS) caused by mutations in ∼27 genes. The vast heterogeneity seen in age and location of disease onset, rate of progression, and duration of disease have been linked with genetic and environmental influences in both SALS and FALS cases. Increased ALS incidence clusters in Guam, southern France, and Maryland have been linked with exposure to Beta-methylamino-L-alanine (BMAA), a non-proteinogenic amino acid produced by cyanobacteria, dinoflaggelates, and diatoms. We embryonically exposed zebrafish, Danio rerio, (transgenically overexpressing a FALS-causing SOD1-G93R mutation) to BMAA to investigate early motor neuron outgrowth in larvae and endurance and fatigability in 5-month adults. SOD1-G93R zebrafish showed decreased embryonic nerve length with increased BMAA dose, a phenotypic change mirrored in 5-month performance measures of weaker swimming and increased fatigability. In contrast, transgenic fish overexpressing wild-type SOD1 were resistant to phenotypic changes, indicating a potential neuroprotective function of healthy SOD1. We show that the etiology of genetic ALS animal models can be influenced by environmental exposures, and that embryonic toxin exposures can result in changes to both early and adult measures. We demonstrate that zebrafish can be a robust model for investigating causes of ALS heterogeneity. Establishing these links between developmental and adult ALS-like symptoms in the zebrafish increases the power of this model for toxicological and drug screens.

  8. A comparative study of embryonic development of some bird species with different patterns of postnatal growth.

    PubMed

    Blom, Jonas; Lilja, Clas

    2005-01-01

    Some studies show that birds with high postnatal growth rates (e.g. altricial species) are characterized by a rapid early development of "supply" organs, such as digestive organs. Birds with low postnatal growth rates (e.g. precocial species) exhibit a slower early development of these organs and a more rapid early development of other "demand" organs, such as brain, muscles, skeleton and feathers. To test whether these differences can be traced back to early embryonic development and whether they can be associated with changes in developmental timing, i.e. heterochrony, we compared embryos of the precocial quail and the altricial fieldfare, two bird species with low and high postnatal growth rates, respectively. We used classical staging techniques that use developmental landmarks to categorize embryonic maturity as well as morphological measurements. These techniques were combined with immune detection of muscle specific proteins in the somites. Our data showed that the anlagen of the head, brain and eyes develop earlier in the quail than in the fieldfare in contrast to the gut which develops earlier in the fieldfare than in the quail. Our data also showed that the quail and the fieldfare displayed different rates of myotome formation in the somites which contribute to muscle formation in the limbs and thorax. We believe these observations are connected with important differences in neonatal characteristics, such as the size of the brain, eyes, organs for locomotion and digestion. This leads us to the conclusion that selection for late ontogenetic characteristics can alter early embryonic development and that growth rate is of fundamental importance for the patterning of avian embryonic development. It also appears that this comparative system offers excellent opportunities to test hypotheses about heterochrony.

  9. Early and late damages induced by heavy charged particle irradiation in embryonic tissue of Arabidopsis seeds

    NASA Astrophysics Data System (ADS)

    Bork, U.; Gartenbach, K. E.; Kranz, A. R.

    Early and late effects of accelerated heavy ions (HZE) on the embryonic tissue of Arabidopsis thaliana seeds were investigated seeing that initial cells of the plant eumeristems resemble the original cells of animal and human tissues with continuous cell proliferation. The endpoints measured were lethality and tumorization in the M1-generation for early effects and embryonic lethality in the M2-generation for late effects. The biological endpoints are plotted as functions of the physical parameters of the irradiation i.e. ion fluence (p/cm2), dose (Gray), charge Z and linear energy transfer (LET). The results presented contribute to the estimation of the principles of biological HZE effects and thus may help to develop a unified theory which could explain the whole sequence from physical and chemical reactions to biological responses connected with heavy ion radiation. Additionally, the data of this paper may be used for the discussion of the quality factor for heavy ion irradiation needed for space missions and for HZE-application in radio-therapy by use of accelerators (UNILAC, (SIS/ESR), BEVALAC).

  10. Transcriptome asymmetry within mouse zygotes but not between early embryonic sister blastomeres

    PubMed Central

    VerMilyea, Matthew D; Maneck, Matthias; Yoshida, Naoko; Blochberger, Isabell; Suzuki, Emi; Suzuki, Toru; Spang, Rainer; Klein, Christoph A; Perry, Anthony C F

    2011-01-01

    Transcriptome regionalization is an essential polarity determinant among metazoans, directing embryonic axis formation during normal development. Although conservation of this principle in mammals is assumed, recent evidence is conflicting and it is not known whether transcriptome asymmetries exist within unfertilized mammalian eggs or between the respective cleavage products of early embryonic divisions. We here address this by comparing transcriptome profiles of paired single cells and sub-cellular structures obtained microsurgically from mouse oocytes and totipotent embryos. Paired microsurgical spindle and remnant samples from unfertilized metaphase II oocytes possessed distinguishable profiles. Fertilization produces a totipotent 1-cell embryo (zygote) and associated spindle-enriched second polar body whose paired profiles also differed, reflecting spindle transcript enrichment. However, there was no programmed transcriptome asymmetry between sister cells within 2- or 3-cell embryos. Accordingly, there is transcriptome asymmetry within mouse oocytes, but not between the sister blastomeres of early embryos. This work places constraints on pre-patterning in mammals and provides documentation correlating potency changes and transcriptome partitioning at the single-cell level. PMID:21468028

  11. Cholesterol-derived glucocorticoids control early fate specification in embryonic stem cells

    PubMed Central

    Cabral-Teixeira, Joaquim; Martinez-Fernandez, Almudena; Cai, Wenqing; Terzic, Andre; Mercola, Mark; Willems, Erik

    2015-01-01

    Summary Aside from its role in cell membrane integrity, cholesterol is a key component in steroid hormone production. The vital functions of steroid hormones such as estrogen, testosterone, glucocorticoids (Gcrts) and mineralocorticoids (Mnrts) in perinatal and adult life are well understood; however, their role during early embryonic development remains largely unexplored. Here we show that siRNA-mediated perturbation of steroid hormone production during mesoderm formation has important consequences on cardiac differentiation in mouse embryonic stem cells (mESC). Both Gcrts and Mnrts are capable of driving cardiac differentiation in mESC. Interestingly, the Gcrt receptor is widely expressed during gastrulation in the mouse, and is exclusively localized in the nuclei - and thus active - in visceral endoderm cells, suggesting that it functions much earlier than previously anticipated. We therefore studied Gcrt signaling in mESC as a model of the gastrulating embryo, and found that Gcrt signaling regulates expression of the transcription factor Hnf4a and the secreted Nodal and BMP inhibitor Cer1 in the early visceral endoderm. RNAi-mediated knockdown of Gcrt function blocked cardiomyocyte differentiation, with limited effects on other cardiovascular cell types including vascular endothelial cells and smooth muscle. Furthermore, the cardiogenic effect of Gcrts required Hnf4a and paracrine Cer1. These results establish a novel function for cholesterol-derived steroid hormones and identify Gcrt signaling in visceral endoderm cells as a regulator of Cer1 and cardiac fate. PMID:26024790

  12. Growth and hemodynamics after early embryonic aortic arch occlusion*

    PubMed Central

    Lindsey, Stephanie E.; Menon, Prahlad G.; Kowalski, William J.; Shekhar, Akshay; Yalcin, Huseyin C.; Nishimura, Nozomi; Schaffer, Chris B.; Butcher, Jonathan T.; Pekkan, Kerem

    2015-01-01

    The majority of severe clinically significant forms of congenital heart disease (CHD) is associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensity required for intervention remain largely unknown. We here combine computational fluid dynamics (CFD) simulations with in vivo experiments to test how individual pharyngeal arch artery hemodynamics alters as a result of local interventions to obstruct individual arch artery flow. Simulated isolated occlusions within each pharyngeal arch artery were created with image derived three-dimensional (3D) reconstructions of normal chick pharyngeal arch anatomy at Hamburger-Hamilton (HH) developmental stages HH18 and HH24. Acute flow redistributions were then computed using in vivo measured subject-specific aortic sinus inflow velocity profiles. A kinematic vascular growth-rendering algorithm was then developed and implemented to test the role of changing local wall shear stress patterns in downstream 3D morphogenesis of arch arteries. CFD simulations predicted that altered pressure gradients and flow redistributions were most sensitive to occlusion of the IVth arches. To evaluate these simulations experimentally, a novel in vivo experimental model of pharyngeal arch occlusion was developed and implemented using two-photon microscopy guided femtosecond laser based photodisruption surgery. The right IVth arch was occluded at HH18, and resulting diameter changes were followed for up to 24 hours. Pharyngeal arch diameter responses to acute hemodynamic changes were predicted qualitatively but poorly quantitatively. Chronic growth and adaptation to hemodynamic changes however were predicted in a subset of arches. Our findings suggest that this complex biodynamic process is governed through more complex forms of mechanobiological

  13. Growth and hemodynamics after early embryonic aortic arch occlusion.

    PubMed

    Lindsey, Stephanie E; Menon, Prahlad G; Kowalski, William J; Shekhar, Akshay; Yalcin, Huseyin C; Nishimura, Nozomi; Schaffer, Chris B; Butcher, Jonathan T; Pekkan, Kerem

    2015-08-01

    The majority of severe clinically significant forms of congenital heart disease (CHD) are associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensity required for intervention remain largely unknown. Here, we combine computational fluid dynamics (CFD) simulations with in vivo experiments to test how individual pharyngeal arch artery hemodynamics alter as a result of local interventions obstructing individual arch artery flow. Simulated isolated occlusions within each pharyngeal arch artery were created with image-derived three-dimensional (3D) reconstructions of normal chick pharyngeal arch anatomy at Hamburger-Hamilton (HH) developmental stages HH18 and HH24. Acute flow redistributions were then computed using in vivo measured subject-specific aortic sinus inflow velocity profiles. A kinematic vascular growth-rendering algorithm was then developed and implemented to test the role of changing local wall shear stress patterns in downstream 3D morphogenesis of arch arteries. CFD simulations predicted that altered pressure gradients and flow redistributions were most sensitive to occlusion of the IVth arches. To evaluate these simulations experimentally, a novel in vivo experimental model of pharyngeal arch occlusion was developed and implemented using two-photon microscopy-guided femtosecond laser-based photodisruption surgery. The right IVth arch was occluded at HH18, and resulting diameter changes were followed for up to 24 h. Pharyngeal arch diameter responses to acute hemodynamic changes were predicted qualitatively but poorly quantitatively. Chronic growth and adaptation to hemodynamic changes, however, were predicted in a subset of arches. Our findings suggest that this complex biodynamic process is governed through more complex forms of mechanobiological

  14. DNA Methylation Variation Trends during the Embryonic Development of Chicken

    PubMed Central

    Li, Shizhao; Zhu, Yufei; Zhi, Lihui; Han, Xiaoying; Shen, Jing; Liu, Yanli; Yao, Junhu; Yang, Xiaojun

    2016-01-01

    The embryogenesis period is critical for epigenetic reprogramming and is thus of great significance in the research field of poultry epigenetics for elucidation of the trends in DNA methylation variations during the embryonic development of birds, particularly due to differences in embryogenesis between birds and mammals. Here, we first examined the variations in genomic DNA methylation during chicken embryogenesis through high-performance liquid chromatography using broilers as the model organism. We then identified the degree of DNA methylation of the promoters and gene bodies involved in two specific genes (IGF2 and TNF-α) using the bisulfite sequencing polymerase chain reaction method. In addition, we measured the expression levels of IGF2, TNF-α and DNA methyltransferase (DNMT) 1, 3a and 3b. Our results showed that the genomic DNA methylation levels in the liver, heart and muscle increased during embryonic development and that the methylation level of the liver was significantly higher in mid-anaphase. In both the muscle and liver, the promoter methylation levels of TNF-α first increased and then decreased, whereas the gene body methylation levels remained lower at embryonic ages E8, 11 and 14 before increasing notably at E17. The promoter methylation level of IGF2 decreased persistently, whereas the methylation levels in the gene body showed a continuous increase. No differences in the expression of TNF-α were found among E8, 11 and 14, whereas a significant increase was observed at E17. IGF2 showed increasing expression level during the examined embryonic stages. In addition, the mRNA and protein levels of DNMTs increased with increasing embryonic ages. These results suggest that chicken shows increasing genomic DNA methylation patterns during the embryonic period. Furthermore, the genomic DNA methylation levels in tissues are closely related to the genes expression levels, and gene expression may be simultaneously regulated by promoter hypomethylation

  15. DNA Methylation Variation Trends during the Embryonic Development of Chicken.

    PubMed

    Li, Shizhao; Zhu, Yufei; Zhi, Lihui; Han, Xiaoying; Shen, Jing; Liu, Yanli; Yao, Junhu; Yang, Xiaojun

    2016-01-01

    The embryogenesis period is critical for epigenetic reprogramming and is thus of great significance in the research field of poultry epigenetics for elucidation of the trends in DNA methylation variations during the embryonic development of birds, particularly due to differences in embryogenesis between birds and mammals. Here, we first examined the variations in genomic DNA methylation during chicken embryogenesis through high-performance liquid chromatography using broilers as the model organism. We then identified the degree of DNA methylation of the promoters and gene bodies involved in two specific genes (IGF2 and TNF-α) using the bisulfite sequencing polymerase chain reaction method. In addition, we measured the expression levels of IGF2, TNF-α and DNA methyltransferase (DNMT) 1, 3a and 3b. Our results showed that the genomic DNA methylation levels in the liver, heart and muscle increased during embryonic development and that the methylation level of the liver was significantly higher in mid-anaphase. In both the muscle and liver, the promoter methylation levels of TNF-α first increased and then decreased, whereas the gene body methylation levels remained lower at embryonic ages E8, 11 and 14 before increasing notably at E17. The promoter methylation level of IGF2 decreased persistently, whereas the methylation levels in the gene body showed a continuous increase. No differences in the expression of TNF-α were found among E8, 11 and 14, whereas a significant increase was observed at E17. IGF2 showed increasing expression level during the examined embryonic stages. In addition, the mRNA and protein levels of DNMTs increased with increasing embryonic ages. These results suggest that chicken shows increasing genomic DNA methylation patterns during the embryonic period. Furthermore, the genomic DNA methylation levels in tissues are closely related to the genes expression levels, and gene expression may be simultaneously regulated by promoter hypomethylation

  16. Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish

    EPA Science Inventory

    Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish Tamara Tal, Integrated Systems Toxicology Division, U.S. EPA Background: There are tens of thousands of chemicals that have yet to be fully evaluated for their toxicity by validated in vivo testing ...

  17. Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish

    EPA Science Inventory

    Developing an Experimental Model of Vascular Toxicity in Embryonic Zebrafish Tamara Tal, Integrated Systems Toxicology Division, U.S. EPA Background: There are tens of thousands of chemicals that have yet to be fully evaluated for their toxicity by validated in vivo testing ...

  18. In silico Testing of Environmental Impact on Embryonic Vascular Development

    EPA Science Inventory

    Understanding risks to embryonic development from exposure to environmental chemicals is a significant challenge given the diverse chemical landscape and paucity of data for most of these compounds. EPA’s Virtual Embryo project is building in silico models of morphogenesis to tes...

  19. In silico Testing of Environmental Impact on Embryonic Vascular Development

    EPA Science Inventory

    Understanding risks to embryonic development from exposure to environmental chemicals is a significant challenge given the diverse chemical landscape and paucity of data for most of these compounds. EPA’s Virtual Embryo project is building in silico models of morphogenesis to tes...

  20. Circulating microRNAs as biomarkers of early embryonic viability in cattle

    USDA-ARS?s Scientific Manuscript database

    Embryonic mortality (EM) is considered to be the primary factor limiting pregnancy success in cattle and occurs early (< day 28) or late (= day 28) during gestation. The incidence of early EM in cattle is approximately 25% while late EM is approximately 3.2 to 42.7%. In cattle, real time ultrasonog...

  1. Variations of X Chromosome Inactivation Occur in Early Passages of Female Human Embryonic Stem Cells

    PubMed Central

    Dvash, Tamar; Lavon, Neta; Fan, Guoping

    2010-01-01

    X chromosome inactivation (XCI) is a dosage compensation mechanism essential for embryonic development and cell physiology. Human embryonic stem cells (hESCs) derived from inner cell mass (ICM) of blastocyst stage embryos have been used as a model system to understand XCI initiation and maintenance. Previous studies of undifferentiated female hESCs at intermediate passages have shown three possible states of XCI; 1) cells in a pre-XCI state, 2) cells that already exhibit XCI, or 3) cells that never undergo XCI even upon differentiation. In this study, XCI status was assayed in ten female hESC lines between passage 5 and 15 to determine whether XCI variations occur in early passages of hESCs. Our results show that three different states of XCI already exist in the early passages of hESC. In addition, we observe one cell line with skewed XCI and preferential expression of X-linked genes from the paternal allele, while another cell line exhibits random XCI. Skewed XCI in undifferentiated hESCs may be due to clonal selection in culture instead of non-random XCI in ICM cells. We also found that XIST promoter methylation is correlated with silencing of XIST transcripts in early passages of hESCs, even in the pre-XCI state. In conclusion, XCI variations already take place in early passages of hESCs, which may be a consequence of in vitro culture selection during the derivation process. Nevertheless, we cannot rule out the possibility that XCI variations in hESCs may reflect heterogeneous XCI states in ICM cells that stochastically give rise to hESCs. PMID:20593031

  2. Nitric Oxide Synthase-3 Promotes Embryonic Development of Atrioventricular Valves

    PubMed Central

    Liu, Yin; Lu, Xiangru; Xiang, Fu-Li; Lu, Man; Feng, Qingping

    2013-01-01

    Nitric oxide synthase-3 (NOS3) has recently been shown to promote endothelial-to-mesenchymal transition (EndMT) in the developing atrioventricular (AV) canal. The present study was aimed to investigate the role of NOS3 in embryonic development of AV valves. We hypothesized that NOS3 promotes embryonic development of AV valves via EndMT. To test this hypothesis, morphological and functional analysis of AV valves were performed in wild-type (WT) and NOS3−/− mice at postnatal day 0. Our data show that the overall size and length of mitral and tricuspid valves were decreased in NOS3−/− compared with WT mice. Echocardiographic assessment showed significant regurgitation of mitral and tricuspid valves during systole in NOS3−/− mice. These phenotypes were all rescued by cardiac specific NOS3 overexpression. To assess EndMT, immunostaining of Snail1 was performed in the embryonic heart. Both total mesenchymal and Snail1+ cells in the AV cushion were decreased in NOS3−/− compared with WT mice at E10.5 and E12.5, which was completely restored by cardiac specific NOS3 overexpression. In cultured embryonic hearts, NOS3 promoted transforming growth factor (TGFβ), bone morphogenetic protein (BMP2) and Snail1expression through cGMP. Furthermore, mesenchymal cell formation and migration from cultured AV cushion explants were decreased in the NOS3−/− compared with WT mice. We conclude that NOS3 promotes AV valve formation during embryonic heart development and deficiency in NOS3 results in AV valve insufficiency. PMID:24204893

  3. Acute embryonic anoxia exposure favours the development of a dominant and aggressive phenotype in adult zebrafish.

    PubMed

    Ivy, Catherine M; Robertson, Cayleih E; Bernier, Nicholas J

    2017-01-11

    Eutrophication and climate change are increasing the incidence of severe hypoxia in fish nursery habitats, yet the programming effects of hypoxia on stress responsiveness in later life are poorly understood. In this study, to investigate whether early hypoxia alters the developmental trajectory of the stress response, zebrafish embryos were exposed to 4 h of anoxia at 36 h post-fertilization and reared to adults when the responses to secondary stressors were assessed. While embryonic anoxia did not affect basal cortisol levels or the cortisol response to hypoxia in later life, it had a marked effect on the responses to a social stressor. In dyadic social interactions, adults derived from embryonic anoxia initiated more chases, bit more often, entered fewer freezes and had lower cortisol levels. Adults derived from embryonic anoxia also performed more bites towards their mirror image, had lower gonadal aromatase gene expression and had higher testosterone levels. We conclude that acute embryonic anoxia has long-lasting consequences for the hormonal and behavioural responses to social interactions in zebrafish. Specifically, we demonstrate that acute embryonic anoxia favours the development of a dominant and aggressive phenotype, and that a disruption in sex steroid production may contribute to the programming effects of environmental hypoxia. © 2017 The Author(s).

  4. Embryonic Development of the Central Nervous System.

    PubMed

    de Lahunta, Alexander; Glass, Eric N; Kent, Marc

    2016-03-01

    Ultimately, it is only with an understanding of normal embryologic development that there can be an understanding of why and how a specific malformation develops. Knowing from where and when a specific part of the nervous system develops and what morphogens are at play will enable us to identify undescribed malformation as well as better define causality. The following article reviews the normal embryologic development of the mammalian nervous system and is intended to serve as a foundation for the understanding of the various malformations presented in this issue.

  5. Investigation of chromosome abnormalities and early embryonic mortality in goose lines.

    PubMed

    Liptói, Krisztina; Hidas, A; Rouvier, R

    2005-01-01

    Early embryonic mortality and chromosome abnormalities were studied in three goose lines: Grey Landes (line 7), White Polish (line 4) and their synthetic line (line 9). Eggs laid at the beginning, in the middle and at the end of the laying season were set. At candling at 5th day after egg set, all eggs (2847) were examined and those showing no normal embryonic development were opened 2847. Dead embryos were classified phenotypically and karyotyped. The mean ratio of embryonic mortality (EM) among fertile eggs was 9.4%, 5.2%, 7.3% in the lines 4, 7 and 9, respectively. The mean ratio of embryos with chromosomal abnormalities (CA) among the dead embryos was 8.0%, 14.8% and 13.1% in the lines 4, 7 and 9, respectively. Gander effect and layer within gander effect on embryo mortality were significant, indicating genetic factors. Father and mother of the layer effects were also significant, showing family effects. Animals producing dead embryos and embryos with chromosome abnormalities in high proportion were selected. In the selected groups the mean EM was 17.7-22.9%, and the mean CA was 11.7-34.7% among the three lines. The repetition of CA was not observed in the reproductive season of following year, while animals repeated the high EM (repeatability coefficient of 0.54). This shows that some part of EM may be resulted from other genetic factors. Ganders and layers progeny of these selected animals showed also high EM. It was concluded that culling pairs giving high EM value in their embryos could increase the average level of embryo viability and that the study of genetic determinism of that trait should be continued in geese.

  6. Quantitative in vivo imaging of embryonic development: opportunities and challenges.

    PubMed

    Gregg, Chelsea L; Butcher, Jonathan T

    2012-07-01

    Animal models are critically important for a mechanistic understanding of embryonic morphogenesis. For decades, visualizing these rapid and complex multidimensional events has relied on projection images and thin section reconstructions. While much insight has been gained, fixed tissue specimens offer limited information on dynamic processes that are essential for tissue assembly and organ patterning. Quantitative imaging is required to unlock the important basic science and clinically relevant secrets that remain hidden. Recent advances in live imaging technology have enabled quantitative longitudinal analysis of embryonic morphogenesis at multiple length and time scales. Four different imaging modalities are currently being used to monitor embryonic morphogenesis: optical, ultrasound, magnetic resonance imaging (MRI), and micro-computed tomography (micro-CT). Each has its advantages and limitations with respect to spatial resolution, depth of field, scanning speed, and tissue contrast. In addition, new processing tools have been developed to enhance live imaging capabilities. In this review, we analyze each type of imaging source and its use in quantitative study of embryonic morphogenesis in small animal models. We describe the physics behind their function, identify some examples in which the modality has revealed new quantitative insights, and then conclude with a discussion of new research directions with live imaging.

  7. Imaging of mouse embryonic eye development using optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Syed, Saba H.; Kasiraj, Alyssa; Larina, Irina V.; Dickinson, Mary E.; Larin, Kirill V.

    2010-02-01

    Congenital abnormalities are often caused by genetic disorders which alter the normal development of the eye. Embryonic eye imaging in mouse model is important for understanding of normal and abnormal eye development and can contribute to prevention and treatment of eye defects in humans. In this study, we used Swept Source Optical Coherence Tomography (SS-OCT) to image eye structure in mouse embryos at 12.5 to 17.5 days post coitus (dpc). The imaging depth of the OCT allowed us to visualize the whole eye globe at these stages. Different ocular tissues including lens, cornea, eyelids, and hyaloid vasculature were visualized. These results suggest that OCT imaging is a useful tool to study embryonic eye development in the mouse model.

  8. Florfenicol induces early embryonic death in eggs collected from treated hens.

    PubMed

    Al-Shahrani, S; Naidoo, V

    2015-08-18

    Florfenicol, a commonly used veterinary antibiotic, was reported to have caused a severe drop in egg hatchability following its off-label use on a broiler breeder farm in South Africa. According to the pharmacovigilance report, hatchability dropped by 80 % for up to a week following a five day course at 10 mg/kg (both males and females treated metaphylactically) to manage an Escherichia coli infection. While mammalian toxicity studies indicate the potential for early embryonic death in utero or testicular damage, no literature is available on the avian toxicity of florfenicol. For this study we investigated the effects of florfenicol at various doses from 10 to 90 mg/kg on the egg hatchability in a breeder flock we kept and established under controlled conditions, with the same cockerels and hens being exposed in a phased manner. Following five days of oral exposure, no toxic signs were evident in any of the cockerels or hens treated at doses up to 90 mg/kg. Treatment of only the cockerels had no effect on egg hatchability, while treatment of only the hens at doses of 60 and 90 mg/kg resulted in decreased hatchability of 0 % in comparison to 70 % of the control as early 24 h after treatment. In all cases, decreased hatchability was associated with embryonic death at 5 days of development. The toxic effects of florfenicol were completely reversible with comparable hatchability being present by day 4 post-treatment withdrawal. Toxicity correlated with total egg florfenicol concentrations with an LC50 of 1.07 μg/g. Florfenicol appears to be toxic to the developing chick embryo at around day 5 of incubation, in the absence of related toxicity in the hen or cockerel.

  9. Development of Scalable Culture Systems for Human Embryonic Stem Cells

    PubMed Central

    Azarin, Samira M.; Palecek, Sean P.

    2009-01-01

    The use of human pluripotent stem cells, including embryonic and induced pluripotent stem cells, in therapeutic applications will require the development of robust, scalable culture technologies for undifferentiated cells. Advances made in large-scale cultures of other mammalian cells will facilitate expansion of undifferentiated human embryonic stem cells (hESCs), but challenges specific to hESCs will also have to be addressed, including development of defined, humanized culture media and substrates, monitoring spontaneous differentiation and heterogeneity in the cultures, and maintaining karyotypic integrity in the cells. This review will describe our current understanding of environmental factors that regulate hESC self-renewal and efforts to provide these cues in various scalable bioreactor culture systems. PMID:20161686

  10. Cadmium affects retinogenesis during zebrafish embryonic development

    SciTech Connect

    Hen Chow, Elly Suk; Yu Hui, Michelle Nga; Cheng, Chi Wa; Cheng, Shuk Han

    2009-02-15

    Ocular malformations are commonly observed in embryos of aquatic species after exposure to toxicants. Using zebrafish embryos as the model organism, we showed that cadmium exposure from sphere stage (4 hpf) to end of segmentation stage (24 hpf) induced microphthalmia in cadmium-treated embryos. Embryos with eye defects were then assessed for visual abilities. Cadmium-exposed embryos were behaviorally blind, showing hyperpigmentation and loss of camouflage response to light. We investigated the cellular basis of the formation of the small eyes phenotype and the induction of blindness by studying retina development and retinotectal projections. Retinal progenitors were found in cadmium-treated embryos albeit in smaller numbers. The number of retinal ganglion cells (RGC), the first class of retinal cells to differentiate during retinogenesis, was reduced, while photoreceptor cells, the last batch of retinal neurons to differentiate, were absent. Cadmium also affected the propagation of neurons in neurogenic waves. The neurons remained in the ventronasal area and failed to spread across the retina. Drastically reduced RGC axons and disrupted optic stalk showed that the optic nerves did not extend from the retina beyond the chiasm into the tectum. Our data suggested that impairment in neuronal differentiation of the retina, disruption in RGC axon formation and absence of cone photoreceptors were the causes of microphthalmia and visual impairment in cadmium-treated embryos.

  11. Beneficial effects of melatonin on in vitro bovine embryonic development are mediated by melatonin receptor 1.

    PubMed

    Wang, Feng; Tian, XiuZhi; Zhang, Lu; Gao, Chao; He, ChangJiu; Fu, Yao; Ji, PengYun; Li, Yu; Li, Ning; Liu, GuoShi

    2014-04-01

    In the current study, a fundamental question, that is, the mechanisms related to the beneficial effects of melatonin on mammalian embryonic development, was addressed. To examine the potential beneficial effects of melatonin on bovine embryonic development, different concentrations of melatonin (10(-11), 10(-9), 10(-7), 10(-5), 10(-3) M) were incubated with fertilized embryos. Melatonin in the range of 10(-11) to 10(-5) M significantly promoted embryonic development both in early culture medium (CR1aa +3 mg/mL BSA) and in later culture medium (CR1aa + 6%FBS). The most effective concentrations applied in the current studies were 10(-9) and 10(-7) M. Using quantitative real-time PCR with immunofluorescence and Western blot assays, the expression of melatonin receptor MT1 and MT2 genes was identified in bovine embryos. Further studies indicate that the beneficial effects of melatonin on bovine embryo development were mediated by the MT1 receptor. This is based on the facts that luzindole, a nonselective MT1 and MT2 antagonist, blocked the effect on melatonin-induced embryo development, while 4-P-PDOT, a selective MT2 antagonist, had little effect. Mechanistic explorations uncovered that melatonin application during bovine embryonic development significantly up-regulated the expression of antioxidative (Gpx4, SOD1, bcl-2) and developmentally important genes (SLC2A1, DNMT1A, and DSC2) while down-regulating expression of pro-apoptotic genes (P53, BAX, and Caspase-3). The results obtained from the current studies provide new information regarding the mechanisms by which melatonin promotes bovine embryonic development under both in vitro and in vivo conditions.

  12. [Embryonic development of the cestode Mosgovoyia ctenoides (Anoplocephalidae)].

    PubMed

    Młocicki, Daniel

    2007-01-01

    In this study the cleavage divisions and the ultrastructural analysis of early embryos as well as cellular organisation of infective oncosphere of the anoplocephalid cestode Mosgovoyia ctenoides are described. The early cleavage is unequal and results in the formation of three types of blastomeres: 2 large macromeres containing large electron dense granules, 3 medium-size mesomeres and several small micromeres. In the early stage of oncospheral morphogenesis, formation of three following primary embryonic envelopes takes place: (1) the capsule replaced by thick, rigid outer coat originated form the uterine material secretion, (2) the outer envelope and (3) the inner envelope. The capsule is formed from the vitellocyte material. Two macromeres contribute to the formation of the outer envelope and three mesomeres take part in the formation of the inner envelope. The inner envelope undergoes differentiation into three sublayers: (1) a thick extraembryophoral cytoplasmic layer, (2) an electron-dense embryophore, as a stiff pyriform apparatus, and (3) a thin intraembryophoral cytoplasmic layer containing mesomere nuclei. The oncosphere is located in the extended cupule-like part of the pyriform apparatus. Four egg envelopes surround the mature infective oncosphere of M. ctenoides: (1) a thick outer coat, (2) the outer envelope, (3) the inner envelope with a characteristic pyriform apparatus and (4) the oncospheral membrane. Hook morphogenesis takes place inside six symmetrically arranged oncoblasts, each of which shows a characteristic large nucleus of semi-lunar shape. At the beginning the "hook-forming center" appears in the cytoplasmic part of each oncoblast. It consists of numerous free ribosomes, polyribosomes, mitochondria and Golgi complexes. The hook-forming center is involved in synthesis of a hook primordium, which undergoes differentiation and elongation into the fully developed hook. Mature hook consists of three parts: (1) blade, (2) shank, (3) base, and at

  13. Human Embryonic Stem Cells: A Model for the Study of Neural Development and Neurological Diseases

    PubMed Central

    Prajumwongs, Piya; Weeranantanapan, Oratai; Jaroonwitchawan, Thiranut; Noisa, Parinya

    2016-01-01

    Although the mechanism of neurogenesis has been well documented in other organisms, there might be fundamental differences between human and those species referring to species-specific context. Based on principles learned from other systems, it is found that the signaling pathways required for neural induction and specification of human embryonic stem cells (hESCs) recapitulated those in the early embryo development in vivo at certain degree. This underscores the usefulness of hESCs in understanding early human neural development and reinforces the need to integrate the principles of developmental biology and hESC biology for an efficient neural differentiation. PMID:27239201

  14. Gene regulatory networks in embryonic stem cells and brain development

    PubMed Central

    Ghosh, Dhimankrishna; Yan, Xiaowei; Tian, Qiang

    2011-01-01

    Embryonic stem cells (ESCs) are endowed with the ability to generate multiple cell lineages and carries great therapeutic potentials in regenerative medicines. Future application of ESCs in human health and diseases will embark on the delineation of molecular mechanisms that define the biology of ESCs. Here we discuss how the finite ESC components mediate the intriguing task of brain development and exhibits biomedical potentials to cure diverse neurological disorders. PMID:19530135

  15. Embryonic and posthatching development of the barn owl (Tyto alba): reference data for age determination.

    PubMed

    Köppl, Christine; Futterer, Eva; Nieder, Bärbel; Sistermann, Ralf; Wagner, Hermann

    2005-08-01

    The normal development of the barn owl was documented with the intent of providing a guideline for determining the maturational stage of embryos and posthatching individuals. Embryonic development up to stage 39 could be well described using the well-known developmental atlas for the chicken (Hamburger and Hamilton [1951] J. Morphol. 88:49-92). For later stages, limb size was established as a suitable indicator. In addition, measuring the egg's vascularized area through candling was found to be a useful, noninvasive method for staging very early embryos, up to stage 25. An average relationship between incubation period and embryonic stage was derived, which showed that development in the barn owl initially lags that in the chicken. For posthatching individuals, skeletal measures (tarsal and ulnar length, skull width and length) were the most reliable parameters for judging maturation, up to 1 month. For older individuals, feather development (e.g., length of primary wing feathers) provided the only cue.

  16. The embryonic epicardium: an essential element of cardiac development

    PubMed Central

    Carmona, R; Guadix, J A; Cano, E; Ruiz-Villalba, A; Portillo-Sánchez, V; Pérez-Pomares, J M; Muñoz-Chápuli, R

    2010-01-01

    Abstract The epicardium has recently been identified as an active and essential element of cardiac development. Recent reports have unveiled a variety of functions performed by the embryonic epicardium, as well as the cellular and molecular mechanisms regulating them. However, despite its developmental importance, a number of unsolved issues related to embryonic epicardial biology persist. In this review, we will summarize our current knowledge about (i) the ontogeny and evolution of the epicardium, including a discussion on the evolutionary origins of the proepicardium (the epicardial primordium), (ii) the nature of epicardial–myocardial interactions during development, known to be essential for myocardial growth and maturation, and (iii) the contribution of epicardially derived cells to the vascular and connective tissue of the heart. We will finish with a note on the relationships existing between the primordia of the viscera and their coelomic epithelial lining. We would like to suggest that at least a part of the properties of the embryonic epicardium are shared by many other coelomic cell types, such that the role of epicardium in cardiac development is a particular example of a more general mechanism for the contribution of coelomic and coelomic-derived cells to the morphogenesis of organs such as the liver, kidneys, gonads or spleen. PMID:20477903

  17. The glucocorticoid-glucocorticoid receptor signal transduction pathway, transforming growth factor-beta, and embryonic mouse lung development in vivo.

    PubMed

    Jaskoll, T; Choy, H A; Melnick, M

    1996-05-01

    Lung morphogenesis has been shown to be regulated by glucocorticoids (CORT). Because CORT has been primarily thought to affect fetal lung development, previous studies have focused on the role of CORT receptor (GR)-mediated regulation of fetal lung development. Although endogenous CORT increases during embryonic and fetal stages and exogenous CORT treatment in vivo and in vitro clearly accelerates embryonic lung development, little is known about the morphoregulatory role of the embryonic CORT-GR signal transduction pathway during lung development. In this study, we characterize the embryonic mouse CORT-GR pathway and demonstrate: stage-specific in situ patterns of GR immunolocalization; similarity in GR relative mobility with progressive (E13 --> E17) development; that embryonic GR can be activated to bind a GR response element (GRE); significantly increasing levels of functional GR with increasing lung maturation; and the presence of heat shock protein (hsp) 70 and hsp90 from early (E13) to late (E17) developmental stages. These results support the purported importance of the embryonic CORT-GR signal transduction pathway in progressive lung differentiation. To demonstrate that the embryonic CORT-GR directed pathway plays a role in lung development, early embryonic (E12) lungs were exposed to CORT in utero and surfactant-associated protein A (SP-A) expression was analyzed; CORT treatment up-regulates SP-A mRNA expression and spatiotemporal protein distribution. Finally, to determine whether CORT-GR-directed pulmonary morphogenesis in vivo involves the modulation of growth factors, we studied the effect of CORT on TGF-beta gene expression. Northern analysis of TGF-beta 1, TGF-beta 2, and TGF-beta 3 transcript levels in vivo indicates that CORT regulates the rate of lung morpho- and histodifferentiation by down-regulating TGF-beta 3 gene expression.

  18. Innovative virtual reality measurements for embryonic growth and development.

    PubMed

    Verwoerd-Dikkeboom, C M; Koning, A H J; Hop, W C; van der Spek, P J; Exalto, N; Steegers, E A P

    2010-06-01

    Innovative imaging techniques, using up-to-date ultrasonic equipment, necessitate specific biometry. The aim of our study was to test the possibility of detailed human embryonic biometry using a virtual reality (VR) technique. In a longitudinal study, three-dimensional (3D) measurements were performed from 6 to 14 weeks gestational age in 32 pregnancies (n = 16 spontaneous conception, n = 16 IVF/ICSI). A total of 125 3D volumes were analysed in the I-Space VR system, which allows binocular depth perception, providing a realistic 3D illusion. Crown-rump length (CRL), biparietal diameter (BPD), occipito-frontal diameter (OFD), head circumference (HC) and abdominal circumference (AC) were measured as well as arm length, shoulder width, elbow width, hip width and knee width. CRL, BPD, OFD and HC could be measured in more than 96% of patients, and AC in 78%. Shoulder width, elbow width, hip width and knee width could be measured in more than 95% of cases, and arm length in 82% of cases. Growth curves were constructed for all variables. Ear and foot measurements were only possible beyond 9 weeks gestation. This study provides a detailed, longitudinal description of normal human embryonic growth, facilitated by a VR system. Growth curves were created for embryonic biometry of the CRL, BPD, HC and AC early in pregnancy and also of several 'new' biometric measurements. Applying virtual embryoscopy will enable us to diagnose growth and/or developmental delay earlier and more accurately. This is especially important for pregnancies at risk of severe complications, such as recurrent late miscarriage and early growth restriction.

  19. Hypoxic level and duration differentially affect embryonic organ system development of the chicken (Gallus gallus).

    PubMed

    Zhang, H; Burggren, W W

    2012-12-01

    Hypoxia inhibits avian embryonic development, as well as increases embryonic mortality. However, the key organ systems affected by hypoxia, and their critical windows for development, are poorly understood. Consequently, chicken embryos were continuously exposed to 3 levels of oxygen (21, 15, or 13% O(2)) throughout d 0 to 10, d 11 to 18, or d 0 to 18 of incubation, followed by morphometric and blood physiological measurements. Hypoxia occurring early during incubation (d 0 to 10) had larger effects on embryonic mortality and organ growth than hypoxia occurring at later stages (d 10 to 18). Growth of the heart and chorioallantoic membrane was stimulated by chronic hypoxia, whereas the lung, brain, eye, liver, stomach, beak, and toes showed no disruption. Sustained hypoxia from the beginning of incubation decreased blood hemoglobin, hematocrit, and red blood cell concentration of embryos at d 10, but the values among hypoxic and normoxic groups were not significantly different at d 18. Blood partial pressure of O(2) and partial pressure of CO(2) were dependent upon incubation O(2) level at a given day of development. These results indicated that either modest hypoxia (15% O(2)) throughout development, or hypoxia at any level during the late stages (d 11 to 18), increased the heart and chorioallantoic membrane weight, which partly compensated for the detrimental effects of hypoxia on embryonic development. We conclude that the first half of embryonic development contained the critical windows for the detrimental effects of hypoxia, and the second half contained the critical windows for the compensatory response of hypoxia in key organs.

  20. The Lin28/Let-7 system in early human embryonic tissue and ectopic pregnancy.

    PubMed

    Lozoya, Teresa; Domínguez, Francisco; Romero-Ruiz, Antonio; Steffani, Liliana; Martínez, Sebastián; Monterde, Mercedes; Ferri, Blanca; Núñez, Maria Jose; AinhoaRomero-Espinós; Zamora, Omar; Gurrea, Marta; Sangiao-Alvarellos, Susana; Vega, Olivia; Simón, Carlos; Pellicer, Antonio; Tena-Sempere, Manuel

    2014-01-01

    Our objective was to determine the expression of the elements of the Lin28/Let-7 system, and related microRNAs (miRNAs), in early stages of human placentation and ectopic pregnancy, as a means to assess the potential role of this molecular hub in the pathogenesis of ectopic gestation. Seventeen patients suffering from tubal ectopic pregnancy (cases) and forty-three women with normal on-going gestation that desired voluntary termination of pregnancy (VTOP; controls) were recruited for the study. Embryonic tissues were subjected to RNA extraction and quantitative PCR analyses for LIN28B, Let-7a, miR-132, miR-145 and mir-323-3p were performed. Our results demonstrate that the expression of LIN28B mRNA was barely detectable in embryonic tissue from early stages of gestation and sharply increased thereafter to plateau between gestational weeks 7-9. In contrast, expression levels of Let-7, mir-132 and mir-145 were high in embryonic tissue from early gestations (≤ 6-weeks) and abruptly declined thereafter, especially for Let-7. Opposite trends were detected for mir-323-3p. Embryonic expression of LIN28B mRNA was higher in early stages (≤ 6-weeks) of ectopic pregnancy than in normal gestation. In contrast, Let-7a expression was significantly lower in early ectopic pregnancies, while miR-132 and miR-145 levels were not altered. Expression of mir-323-3p was also suppressed in ectopic embryonic tissue. We are the first to document reciprocal changes in the expression profiles of the gene encoding the RNA-binding protein, LIN28B, and the related miRNAs, Let-7a, mir-132 and mir-145, in early stages of human placentation. This finding suggests the potential involvement of LIN28B/Let-7 (de)regulated pathways in the pathophysiology of ectopic pregnancy in humans.

  1. Early embryonic-like cells are induced by downregulating replication-dependent chromatin assembly.

    PubMed

    Ishiuchi, Takashi; Enriquez-Gasca, Rocio; Mizutani, Eiji; Bošković, Ana; Ziegler-Birling, Celine; Rodriguez-Terrones, Diego; Wakayama, Teruhiko; Vaquerizas, Juan M; Torres-Padilla, Maria-Elena

    2015-09-01

    Cellular plasticity is essential for early embryonic cells. Unlike pluripotent cells, which form embryonic tissues, totipotent cells can generate a complete organism including embryonic and extraembryonic tissues. Cells resembling 2-cell-stage embryos (2C-like cells) arise at very low frequency in embryonic stem (ES) cell cultures. Although induced reprogramming to pluripotency is well established, totipotent cells remain poorly characterized, and whether reprogramming to totipotency is possible is unknown. We show that mouse 2C-like cells can be induced in vitro through downregulation of the chromatin-assembly activity of CAF-1. Endogenous retroviruses and genes specific to 2-cell embryos are the highest-upregulated genes upon CAF-1 knockdown. Emerging 2C-like cells exhibit molecular characteristics of 2-cell embryos and higher reprogrammability than ES cells upon nuclear transfer. Our results suggest that early embryonic-like cells can be induced by modulating chromatin assembly and that atypical histone deposition may trigger the emergence of totipotent cells.

  2. Paternal identity impacts embryonic development for two species of freshwater fish.

    PubMed

    Siddique, Mohammad Abdul Momin; Linhart, Otomar; Krejszeff, Sławomir; Żarski, Daniel; Pitcher, Trevor E; Politis, Sebastian Nikitas; Butts, Ian Anthony Ernest

    2017-05-01

    Paternal, compared to maternal, contributions were believed to have only a limited influence on embryonic development and larval fitness traits in fishes. Therefore, the perspective of male influence on early life history traits has come under scrutiny. This study was conducted to determine parental effects on the rate of eyed embryos of Ide Leuciscus idus and Northern pike Esox lucius. Five sires and five dams from each species were crossed using a quantitative genetic breeding design and the resulting 25 sib groups of each species were reared to the embryonic eyed stage. We then partition variation in embryonic phenotypic performance to maternal, paternal, and parental interactions using the Restricted Maximum Likelihood (REML) model. Results showed that paternal, maternal, and the paternal×maternal interaction terms were highly significant for both species; clearly demonstrating that certain family combinations were more compatible than others. Paternal effects explained 20.24% of the total variance, which was 2-fold higher than the maternal effects (10.73%) in Ide, while paternal effects explained 18.9% of the total variance, which was 15-fold higher than the maternal effects (1.3%) in Northern pike. Together, these results indicate that male effects are of major importance during embryonic development for these species. Furthermore, this study demonstrates that genetic compatibility between sires and dams plays an important role and needs to be taken into consideration for reproduction of these and likely other economically important fish species. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Effects of embryonic exposure to polychlorinated biphenyls on zebrafish skeletal development.

    PubMed

    Ju, Li; Tang, Kai; Guo, Xi-Rong; Yang, Yang; Zhu, Guan-Zhong; Lou, Yue

    2012-05-01

    Polychlorinated biphenyls (PCBs) are persistent organic pollutants that affect embryonic development. The purpose of this study was to examine the effects of embryonic exposure to PCBs on early skeletal development in zebrafish (Danio rerio). Zebrafish embryos were immediately exposed to various concentrations (0, 0.125, 0.25, 0.5 and 1.0 mg/l) of PCBs (Aroclor 1254) after fertilization. Embryos were assessed at 24, 48, 72, 96 and 120 h post-fertilization (hpf) for changes in embryonic survival and malformation rates. Calcium content and vitamin D receptor (VDR), parathyroid hormone (PTH) and TRVP6 mRNA expressions were assessed at 120 hpf. The results showed that PCBs exposure decreased the survival rate of the embryos in a time-and dose-dependent manner. The embryos exposed to the higher concentrations of PCBs (0.5 and 1.0 mg/l) displayed obvious skeletal morphological deformities. At 120 hpf, the calcium content of the zebrafish was downregulated in all the PCB-treated groups. VDR, PTH and TRVP6 mRNA expressions were all affected by PCBs. By 120 hpf, the mRNA expressions of VDR, PTH and TRVP6 from the PCB-treated larvae were all upregulated. The expressions of PTH and TRVP6 positively correlated with the level of PCBs to which the embryos were exposed. These results suggest that embryonic exposure to PCBs induces developmental deficits in the zebrafish skeleton.

  4. Embryonic development of rat diaphragm. An electron-microscopic study.

    PubMed

    Angelov, D N; Manolov, S A

    1989-01-01

    Ultrastructural aspects of white Wistar rats diaphragm during part of its embryonic development (from the 13th embryonic day till birth) have been studied. The dominating structures observed in the period of the thirteenth embryonic day (ED 13) are undifferentiated cells, their cytoplasm being poor in organelles but rich in ribosomes. The close examination of these cells reveals that some of them possess a kind of thin filaments near their Golgi zones. At ED 14-15 clusters of myoblasts are readily detected (their cytoplasm containing a lot of glycogen granules and myofibrils, some of them even with Z-line material); contact sites between their cell membranes appear, somewhere forming specialized junctions; in this period the myoblasts start to fuse giving rise to the primary generation of myotubes. At ED 16-17 the quantity of myofilaments and glycogen granules increases alongside with the initiation of a basal-lamina formation; occasionally some oval, undifferentiated cells very similar to those viewed at ED 13 are found. At ED 18-19 the cytoplasm of the myotubes contains a lot of myofibrils and a well-developed endoplasmic reticulum; at some places the adjacent membranes still form deep interdigitations. At the end of the prenatal myogenesis (ED 20-21) most of the muscle cells are close to their mature morphological appearance--the sarcomers are well-organized and some nuclei present a peripheral localization; nevertheless, in this period new generations of myotubes can be also distinguished.

  5. Predictive computation of genomic logic processing functions in embryonic development

    PubMed Central

    Peter, Isabelle S.; Faure, Emmanuel; Davidson, Eric H.

    2012-01-01

    Gene regulatory networks (GRNs) control the dynamic spatial patterns of regulatory gene expression in development. Thus, in principle, GRN models may provide system-level, causal explanations of developmental process. To test this assertion, we have transformed a relatively well-established GRN model into a predictive, dynamic Boolean computational model. This Boolean model computes spatial and temporal gene expression according to the regulatory logic and gene interactions specified in a GRN model for embryonic development in the sea urchin. Additional information input into the model included the progressive embryonic geometry and gene expression kinetics. The resulting model predicted gene expression patterns for a large number of individual regulatory genes each hour up to gastrulation (30 h) in four different spatial domains of the embryo. Direct comparison with experimental observations showed that the model predictively computed these patterns with remarkable spatial and temporal accuracy. In addition, we used this model to carry out in silico perturbations of regulatory functions and of embryonic spatial organization. The model computationally reproduced the altered developmental functions observed experimentally. Two major conclusions are that the starting GRN model contains sufficiently complete regulatory information to permit explanation of a complex developmental process of gene expression solely in terms of genomic regulatory code, and that the Boolean model provides a tool with which to test in silico regulatory circuitry and developmental perturbations. PMID:22927416

  6. Developing Human Embryonic Stem Cells for Grafting in Parkinson’s Disease

    DTIC Science & Technology

    2007-03-01

    AD_________________ Award Number: W81XWH-04-1-0366 TITLE: Developing human embryonic stem cells ...Mar 04 – 28 Feb 07 4. TITLE AND SUBTITLE Developing human embryonic stem cells for grafting in Parkinson’s disease 5a...TERMS Parkinson’s disease, transplantation, embryonic stem cell , neuronal differentiation, dopamine, xenograft, functional recovery 16. SECURITY

  7. Embryonic development of Xenopus laevis under static magnetic fields up to 6.34 T

    NASA Astrophysics Data System (ADS)

    Ueno, S.; Shiokawa, K.; Iwamoto, M.

    1990-05-01

    A possible influence of intense magnetic fields on the embryonic development of frogs was studied in reference to a potential hazardous problem in magnetic resonance imaging technology. Fertilized eggs of African clawed toads, Xenopus laevis, were cultured in Amphibian Ringer solution under static magnetic fields up to 6.34 T for varying lengths of time, and their cleavage and early embryonic development were followed to examine the possibility of teratogenic effects. Fertilized eggs cultured under the static magnetic field for 6 h followed normal course of cleavage and normally developed into feeding tadpoles. Results were unchanged even when fertilized eggs were cultured for 18 h from the cleavage stage to the neurula stage under a magnetic field of 4.5 T. We conclude that static magnetic fields up to 6.34 T do not affect appreciably the rapid cleavage and the following cell multiplication and differentiation in Xenopus laevis.

  8. Essential Role of Chromatin Remodeling Protein Bptf in Early Mouse Embryos and Embryonic Stem Cells

    PubMed Central

    Landry, Joseph; Sharov, Alexei A.; Piao, Yulan; Sharova, Lioudmila V.; Xiao, Hua; Southon, Eileen; Matta, Jennifer; Tessarollo, Lino; Zhang, Ying E.; Ko, Minoru S. H.; Kuehn, Michael R.; Yamaguchi, Terry P.; Wu, Carl

    2008-01-01

    We have characterized the biological functions of the chromatin remodeling protein Bptf (Bromodomain PHD-finger Transcription Factor), the largest subunit of NURF (Nucleosome Remodeling Factor) in a mammal. Bptf mutants manifest growth defects at the post-implantation stage and are reabsorbed by E8.5. Histological analyses of lineage markers show that Bptf−/− embryos implant but fail to establish a functional distal visceral endoderm. Microarray analysis at early stages of differentiation has identified Bptf-dependent gene targets including homeobox transcriptions factors and genes essential for the development of ectoderm, mesoderm, and both definitive and visceral endoderm. Differentiation of Bptf−/− embryonic stem cell lines into embryoid bodies revealed its requirement for development of mesoderm, endoderm, and ectoderm tissue lineages, and uncovered many genes whose activation or repression are Bptf-dependent. We also provide functional and physical links between the Bptf-containing NURF complex and the Smad transcription factors. These results suggest that Bptf may co-regulate some gene targets of this pathway, which is essential for establishment of the visceral endoderm. We conclude that Bptf likely regulates genes and signaling pathways essential for the development of key tissues of the early mouse embryo. PMID:18974875

  9. Single nucleotide polymorphisms in candidate genes associated with fertilizing ability of sperm and subsequent embryonic development in cattle

    USDA-ARS?s Scientific Manuscript database

    Fertilization and development of the preimplantation embryo is under genetic control. The goal of the current study was to test 434 single nucleotide polymorphisms (SNPs) for association with genetic variation in fertilization and early embryonic development. The approach was to produce embryos from...

  10. MRG15 Regulates Embryonic Development and Cell Proliferation

    PubMed Central

    Tominaga, Kaoru; Kirtane, Bhakti; Jackson, James G.; Ikeno, Yuji; Ikeda, Takayoshi; Hawks, Christina; Smith, James R.; Matzuk, Martin M.; Pereira-Smith, Olivia M.

    2005-01-01

    MRG15 is a highly conserved protein, and orthologs exist in organisms from yeast to humans. MRG15 associates with at least two nucleoprotein complexes that include histone acetyltransferases and/or histone deacetylases, suggesting it is involved in chromatin remodeling. To study the role of MRG15 in vivo, we generated knockout mice and determined that the phenotype is embryonic lethal, with embryos and the few stillborn pups exhibiting developmental delay. Immunohistochemical analysis indicates that apoptosis in Mrg15−/− embryos is not increased compared with wild-type littermates. However, the number of proliferating cells is significantly reduced in various tissues of the smaller null embryos compared with control littermates. Cell proliferation defects are also observed in Mrg15−/− mouse embryonic fibroblasts. The hearts of the Mrg15−/− embryos exhibit some features of hypertrophic cardiomyopathy. The increase in size of the cardiomyocytes is most likely a response to decreased growth of the cells. Mrg15−/− embryos appeared pale, and microarray analysis revealed that α-globin gene expression was decreased in null versus wild-type embryos. We determined by chromatin immunoprecipitation that MRG15 was recruited to the α-globin promoter during dimethyl sulfoxide-induced mouse erythroleukemia cell differentiation. These findings demonstrate that MRG15 has an essential role in embryonic development via chromatin remodeling and transcriptional regulation. PMID:15798182

  11. Choreography of early thalamocortical development.

    PubMed

    Molnár, Zoltán; Higashi, Shuji; López-Bendito, Guillermina

    2003-06-01

    Thalamic axons, which carry most of the information from the sensory environment, are amongst the first projections to reach the cerebral cortex during embryonic development. It has been proposed that the scaffold of early generated cells in the ventral thalamus, internal capsule and preplate play a pivotal role in their deployment through sharp gene expression boundaries. These ideas were recently evaluated in various strains of mutant mice. In Tbr1, Gbx2, Pax6 KO both thalamic and corticofugal projections fail to traverse the striatocortical junction. In both Emx2 and Pax6 KO brains, the misrouted thalamic afferents are accompanied by displacements of the pioneering projections from the internal capsule. Regardless of their altered route, thalamic afferents in the reeler and L1 KO mice seem to be able to redistribute themselves on the cortical sheet and establish normal periphery-related representation in the somatosensory cortex. Early neural activity delivered through the thalamic projections is thought to be involved in the realignment process of thalamic axons at the time of their accumulation in the subplate layer. However, axonal growth and the early topographic arrangement of thalamocortical fiber pathways appear normal in the Snap25 KO, where action potential mediated synaptic vesicle release is disrupted. We therefore suggest that intercellular communication mediated by constitutive secretion of transmitters or growth factors might play a dominant role during early thalamocortical development.

  12. Early Embryonic Vascular Patterning by Matrix-Mediated Paracrine Signalling: A Mathematical Model Study

    PubMed Central

    Köhn-Luque, Alvaro; de Back, Walter; Starruß, Jörn; Mattiotti, Andrea; Deutsch, Andreas; Pérez-Pomares, José María; Herrero, Miguel A.

    2011-01-01

    During embryonic vasculogenesis, endothelial precursor cells of mesodermal origin known as angioblasts assemble into a characteristic network pattern. Although a considerable amount of markers and signals involved in this process have been identified, the mechanisms underlying the coalescence of angioblasts into this reticular pattern remain unclear. Various recent studies hypothesize that autocrine regulation of the chemoattractant vascular endothelial growth factor (VEGF) is responsible for the formation of vascular networks in vitro. However, the autocrine regulation hypothesis does not fit well with reported data on in vivo early vascular development. In this study, we propose a mathematical model based on the alternative assumption that endodermal VEGF signalling activity, having a paracrine effect on adjacent angioblasts, is mediated by its binding to the extracellular matrix (ECM). Detailed morphometric analysis of simulated networks and images obtained from in vivo quail embryos reveals the model mimics the vascular patterns with high accuracy. These results show that paracrine signalling can result in the formation of fine-grained cellular networks when mediated by angioblast-produced ECM. This lends additional support to the theory that patterning during early vascular development in the vertebrate embryo is regulated by paracrine signalling. PMID:21949696

  13. Embryonic and early foetal losses in cattle and other ruminants.

    PubMed

    Diskin, M G; Morris, D G

    2008-07-01

    Embryo survival is a major factor affecting production and economic efficiency in all systems of ruminant milk and meat production. For heifers, beef and moderate yielding dairy cows, does and camelids it appears that fertilization generally lies between 90% and 100%. In high-producing dairy cows there is a less substantive body of literature, but it would appear that it is somewhat lower and perhaps more variable. In cattle, the major component of embryo loss occurs before day 16 following breeding with some evidence of greater losses before day 8 in high-producing dairy cows. In cattle late embryo loss, while numerically much smaller than early embryo mortality loss, nevertheless, causes serious economic losses to producers because it is often too late to rebreed females when they repeat. In multiple ovulating small ruminants, the loss rate is positively related to ovulation rate. Systemic concentrations of progesterone, during both the cycle preceding and following insemination, affect embryo survival rate with evidence that too high or indeed too low a concentration being negatively associated with survival rate. Uterine expression of mRNA for progesterone receptor, oestradiol receptor and retinol-binding protein appears to be sensitive to changes in peripheral concentrations of progesterone during the first week after artificial insemination. Energy balance and dry matter intake during 4 weeks after calving are critically important in determining conception rate when cows are inseminated at 70-100 days post-calving. Concentrate supplementation of cows at pasture during the breeding period has minimal effects on conception rates though sudden reductions in dietary intake should be avoided. For all systems of milk production, more balanced breeding strategies with greater emphasis on fertility and feed intake and/or energy balance must be developed. There is sufficient genetic variability within the Holstein breed for fertility traits. Alternative dairy breeds

  14. Kinetics of energy source utilization in Boophilus microplus (Canestrini, 1887) (Acari: Ixodidae) embryonic development.

    PubMed

    Campos, Eldo; Moraes, Jorge; Façanha, Arnoldo R; Moreira, Erica; Valle, Denise; Abreu, Leonardo; Manso, Pedro P A; Nascimento, Aline; Pelajo-Machado, Marcelo; Lenzi, Henrique; Masuda, Aoi; Vaz, Itabajara da Silva; Logullo, Carlos

    2006-06-15

    The present work evaluates the kinetics of utilization of the main potential energy sources throughout the embryonic developmental stages of Boophilus microplus. The embryonic development of this arthropod is completed in 21 days. Cellularization of the blastoderm occurs on the 6th day and is rapidly followed by germ band extension and segmentation, whose first signs are visible on the 7th day. Cellularization is typically a maternal-driven process, carried out by molecular determinants deposited in the oocyte during oogenesis. On the other hand, segmentation is of zygotic nature, being the consequence of the synthesis of various components by the growing embryo. The enhancement in total B. microplus RNA was observed after cellularization, corroborating the replacement of maternal-driven processes by embryonic zygotic expression. An abrupt increase in oxygen consumption was observed from cellularization until the 8th day of development. The reduction in dry weight at the same period and the susceptibility of oxygen consumption to KCN suggest that the respiration process is activated during early embryonic development. A marked decrease in total lipid content occurred between the 5th and 7th days of development, suggesting this is the main energy source for cellularization. A major reduction in carbohydrate content occurred later, between the 7th and 9th days, and it could be assigned to the morphological segmentation of the embryo. Although the total amount of proteins remains unchanged from oviposition to hatching, a 15% reduction in vitellin (VT) content was observed before cellularization, up to the 4th day after egglaying. This observation was correlated to the synthesis of new proteins needed to support early embryo development. Additional 20% of VT was consumed thereafter, mainly at the end of embryogenesis, and in this case VT is probably used as energy source to the older embryo. Altogether, these data indicate different energy sources for maternal and

  15. Characterization of mechanical and biochemical properties of developing embryonic tendon

    PubMed Central

    Marturano, Joseph E.; Arena, Jeffrey D.; Schiller, Zachary A.; Georgakoudi, Irene; Kuo, Catherine K.

    2013-01-01

    Tendons have uniquely high tensile strength, critical to their function to transfer force from muscle to bone. When injured, their innate healing response results in aberrant matrix organization and functional properties. Efforts to regenerate tendon are challenged by limited understanding of its normal development. Consequently, there are few known markers to assess tendon formation and parameters to design tissue engineering scaffolds. We profiled mechanical and biological properties of embryonic tendon and demonstrated functional properties of developing tendon are not wholly reflected by protein expression and tissue morphology. Using force volume-atomic force microscopy, we found that nano- and microscale tendon elastic moduli increase nonlinearly and become increasingly spatially heterogeneous during embryonic development. When we analyzed potential biochemical contributors to modulus, we found statistically significant but weak correlation between elastic modulus and collagen content, and no correlation with DNA or glycosaminoglycan content, indicating there are additional contributors to mechanical properties. To investigate collagen cross-linking as a potential contributor, we inhibited lysyl oxidase-mediated collagen cross-linking, which significantly reduced tendon elastic modulus without affecting collagen morphology or DNA, glycosaminoglycan, and collagen content. This suggests that lysyl oxidase-mediated cross-linking plays a significant role in the development of embryonic tendon functional properties and demonstrates that changes in cross-links alter mechanical properties without affecting matrix content and organization. Taken together, these data demonstrate the importance of functional markers to assess tendon development and provide a profile of tenogenic mechanical properties that may be implemented in tissue engineering scaffold design to mechanoregulate new tendon regeneration. PMID:23576745

  16. Characterization of mechanical and biochemical properties of developing embryonic tendon.

    PubMed

    Marturano, Joseph E; Arena, Jeffrey D; Schiller, Zachary A; Georgakoudi, Irene; Kuo, Catherine K

    2013-04-16

    Tendons have uniquely high tensile strength, critical to their function to transfer force from muscle to bone. When injured, their innate healing response results in aberrant matrix organization and functional properties. Efforts to regenerate tendon are challenged by limited understanding of its normal development. Consequently, there are few known markers to assess tendon formation and parameters to design tissue engineering scaffolds. We profiled mechanical and biological properties of embryonic tendon and demonstrated functional properties of developing tendon are not wholly reflected by protein expression and tissue morphology. Using force volume-atomic force microscopy, we found that nano- and microscale tendon elastic moduli increase nonlinearly and become increasingly spatially heterogeneous during embryonic development. When we analyzed potential biochemical contributors to modulus, we found statistically significant but weak correlation between elastic modulus and collagen content, and no correlation with DNA or glycosaminoglycan content, indicating there are additional contributors to mechanical properties. To investigate collagen cross-linking as a potential contributor, we inhibited lysyl oxidase-mediated collagen cross-linking, which significantly reduced tendon elastic modulus without affecting collagen morphology or DNA, glycosaminoglycan, and collagen content. This suggests that lysyl oxidase-mediated cross-linking plays a significant role in the development of embryonic tendon functional properties and demonstrates that changes in cross-links alter mechanical properties without affecting matrix content and organization. Taken together, these data demonstrate the importance of functional markers to assess tendon development and provide a profile of tenogenic mechanical properties that may be implemented in tissue engineering scaffold design to mechanoregulate new tendon regeneration.

  17. Can physics help to explain embryonic development? An overview.

    PubMed

    Fleury, V

    2013-10-01

    Recent technical advances including digital imaging and particle image velocimetry can be used to extract the full range of embryonic movements that constitute the instantaneous 'morphogenetic fields' of a developing animal. The final shape of the animal results from the sum over time (integral) of the movements that make up the velocity fields of all the tissue constituents. In vivo microscopy can be used to capture the details of vertebrate development at the earliest embryonic stages. The movements thus observed can be quantitatively compared to physical models that provide velocity fields based on simple hypotheses about the nature of living matter (a visco-elastic gel). This approach has cast new light on the interpretation of embryonic movement, folding, and organisation. It has established that several major discontinuities in development are simple physical changes in boundary conditions. In other words, with no change in biology, the physical consequences of collisions between folds largely explain the morphogenesis of the major structures (such as the head). Other discontinuities result from changes in physical conditions, such as bifurcations (changes in physical behaviour beyond specific yield points). For instance, beyond a certain level of stress, a tissue folds, without any new gene being involved. An understanding of the physical features of movement provides insights into the levers that drive evolution; the origin of animals is seen more clearly when viewed under the light of the fundamental physical laws (Newton's principle, action-reaction law, changes in symmetry breaking scale). This article describes the genesis of a vertebrate embryo from the shapeless stage (round mass of tissue) to the development of a small, elongated, bilaterally symmetric structure containing vertebral precursors, hip and shoulder enlarges, and a head.

  18. Increased Hemodynamic Load in Early Embryonic Stages Alters Endocardial to Mesenchymal Transition

    PubMed Central

    Midgett, Madeline; López, Claudia S.; David, Larry; Maloyan, Alina; Rugonyi, Sandra

    2017-01-01

    Normal blood flow is essential for proper heart formation during embryonic development, as abnormal hemodynamic load (blood pressure and shear stress) results in cardiac defects seen in congenital heart disease. However, the progressive detrimental remodeling processes that relate altered blood flow to cardiac defects remain unclear. Endothelial–mesenchymal cell transition is one of the many complex developmental events involved in transforming the early embryonic outflow tract into the aorta, pulmonary trunk, interventricular septum, and semilunar valves. This study elucidated the effects of increased hemodynamic load on endothelial–mesenchymal transition remodeling of the outflow tract cushions in vivo. Outflow tract banding was used to increase hemodynamic load in the chicken embryo heart between Hamburger and Hamilton stages 18 and 24. Increased hemodynamic load induced increased cell density in outflow tract cushions, fewer cells along the endocardial lining, endocardium junction disruption, and altered periostin expression as measured by confocal microscopy analysis. In addition, 3D focused ion beam scanning electron microscopy analysis determined that a portion of endocardial cells adopted a migratory shape after outflow tract banding that is more irregular, elongated, and with extensive cellular projections compared to normal cells. Proteomic mass-spectrometry analysis quantified altered protein composition after banding that is consistent with a more active stage of endothelial–mesenchymal transition. Outflow tract banding enhances the endothelial–mesenchymal transition phenotype during formation of the outflow tract cushions, suggesting that endothelial–mesenchymal transition is a critical developmental process that when disturbed by altered blood flow gives rise to cardiac malformation and defects. PMID:28228731

  19. Mutation in ankyrin repeats of the mouse Notch2 gene induces early embryonic lethality.

    PubMed

    Hamada, Y; Kadokawa, Y; Okabe, M; Ikawa, M; Coleman, J R; Tsujimoto, Y

    1999-08-01

    Notch family genes encode transmembrane proteins involved in cell-fate determination. Using gene targeting procedures, we disrupted the mouse Notch2 gene by replacing all but one of the ankyrin repeat sequences in the cytoplasmic domain with the E. coli (beta)-galactosidase gene. The mutant Notch2 gene encodes a 380 kDa Notch2-(beta)-gal fusion protein with (beta)-galactosidase activity. Notch2 homozygous mutant mice die prior to embryonic day 11.5, whereas heterozygotes show no apparent abnormalities and are fully viable. Analysis of Notch2 expression patterns, revealed by X-gal staining, demonstrated that the Notch2 gene is expressed in a wide variety of tissues including neuroepithelia, somites, optic vesicles, otic vesicles, and branchial arches, but not heart. Histological studies, including in situ nick end labeling procedures, showed earlier onset and higher incidence of apoptosis in homozygous mutant mice than in heterozygotes or wild type mice. Dying cells were particularly evident in neural tissues, where they were seen as early as embryonic day 9.5 in Notch2-deficient mice. Cells from Notch2 mutant mice attach and grow normally in culture, demonstrating that Notch2 deficiency does not interfere with cell proliferation and that expression of the Notch2-(beta)-gal fusion protein is not toxic per se. In contrast to Notch1-deficient mice, Notch2 mutant mice did not show disorganized somitogenesis, nor did they fail to properly regulate the expression of neurogenic genes such as Hes-5 or Mash1. In situ hybridization studies show no indication of altered Notch1 expression patterns in Notch2 mutant mice. The results indicate that Notch2 plays an essential role in postimplantation development in mice, probably in some aspect of cell specification and/or differentiation, and that the ankyrin repeats are indispensable for its function.

  20. Embryonic muscle development in direct and indirect developing marine flatworms (Platyhelminthes, Polycladida).

    PubMed

    Bolaños, D Marcela; Litvaitis, Marian K

    2009-01-01

    We compared embryonic myogenesis of the direct-developing acotylean polyclad Melloplana ferruginea with that of Maritigrella crozieri, a cotylean that develops via a larval stage. Fluorescently labeled F-actin was visualized with laser confocal microscopy. Developmental times are reported as percentages of the time from oviposition to hatching: 7 days for M. crozieri and 22 days for M. ferruginea. The epithelium began to form at 30% development in M. crozieri and at 15% development in M. ferruginea. Random myoblasts appeared in peripheral areas of the embryo at 36% and 22-30% development in M. crozeri and M. ferruginea, respectively. Circular and longitudinal muscle bands formed synchronously at 37-44% development in M. crozieri; yolk obscured observations of early myogenesis in M. ferruginea. An orthogonal muscle grid was established by 45-50% development in both species. Diagonal muscles developed in M. ferruginea at 60-71% development. Hence, juveniles of this species hatch with the same basic body-wall musculature as adults. Larvae of M. crozieri did not hatch with diagonal muscles; these muscles are acquired postmetamorphosis. Additionally, a specialized musculature developed in the larval lobes of M. crozieri. Oral musculature was complex and established by 72% development in both species. Our results are comparable to the muscle differentiation reported for other indirect-developing polyclads and for direct-developing species of macrostomid flatworms. Furthermore, they provide additional support that the orthogonal muscle pattern of circular and longitudinal muscles is a symplesiomorphy of Spiralia.

  1. The embryonic development of the central American wandering spider Cupiennius salei

    PubMed Central

    2011-01-01

    Background The spider Cupiennius salei (Keyserling 1877) has become an important study organism in evolutionary and developmental biology. However, the available staging system for its embryonic development is difficult to apply to modern studies, with strong bias towards the earliest developmental stages. Furthermore, important embryonic events are poorly understood. We address these problems, providing a new description of the embryonic development of C. salei. The paper also discusses various observations that will improve our understanding of spider development. Results Conspicuous developmental events were used to define numbered stages 1 to 21. Stages 1 to 9 follow the existing staging system for the spider Achaearanea tepidariorum, and stages 10 to 21 provide a high-resolution description of later development. Live-embryo imaging shows cell movements during the earliest formation of embryonic tissue in C. salei. The imaging procedure also elucidates the encircling border between the cell-dense embryo hemisphere and the hemisphere with much lower cell density (a structure termed 'equator' in earlier studies). This border results from subsurface migration of primordial mesendodermal cells from their invagination site at the blastopore. Furthermore, our detailed successive sequence shows: 1) early differentiation of the precheliceral neuroectoderm; 2) the morphogenetic process of inversion and 3) initial invaginations of the opisthosomal epithelium for the respiratory system. Conclusions Our improved staging system of development in C. salei development should be of considerable value to future comparative studies of animal development. A dense germ disc is not evident during development in C. salei, but we show that the gastrulation process is similar to that in spider species that do have a dense germ disc. In the opisthosoma, the order of appearance of precursor epithelial invaginations provides evidence for the non-homology of the tracheal and book lung

  2. Gene expression signatures defining fundamental biological processes in pluripotent, early, and late differentiated embryonic stem cells.

    PubMed

    Gaspar, John Antonydas; Doss, Michael Xavier; Winkler, Johannes; Wagh, Vilas; Hescheler, Jürgen; Kolde, Raivo; Vilo, Jaak; Schulz, Herbert; Sachinidis, Agapios

    2012-09-01

    Investigating the molecular mechanisms controlling the in vivo developmental program postembryogenesis is challenging and time consuming. However, the developmental program can be partly recapitulated in vitro by the use of cultured embryonic stem cells (ESCs). Similar to the totipotent cells of the inner cell mass, gene expression and morphological changes in cultured ESCs occur hierarchically during their differentiation, with epiblast cells developing first, followed by germ layers and finally somatic cells. Combination of high throughput -omics technologies with murine ESCs offers an alternative approach for studying developmental processes toward organ-specific cell phenotypes. We have made an attempt to understand differentiation networks controlling embryogenesis in vivo using a time kinetic, by identifying molecules defining fundamental biological processes in the pluripotent state as well as in early and the late differentiation stages of ESCs. Our microarray data of the differentiation of the ESCs clearly demonstrate that the most critical early differentiation processes occur at days 2 and 3 of differentiation. Besides monitoring well-annotated markers pertinent to both self-renewal and potency (capacity to differentiate to different cell lineage), we have identified candidate molecules for relevant signaling pathways. These molecules can be further investigated in gain and loss-of-function studies to elucidate their role for pluripotency and differentiation. As an example, siRNA knockdown of MageB16, a gene highly expressed in the pluripotent state, has proven its influence in inducing differentiation when its function is repressed.

  3. Calcineurin-NFAT signaling critically regulates early lineage specification in mouse embryonic stem cells and embryos.

    PubMed

    Li, Xiang; Zhu, Lili; Yang, Acong; Lin, Jiangwei; Tang, Fan; Jin, Shibo; Wei, Zhe; Li, Jinsong; Jin, Ying

    2011-01-07

    Self-renewal and pluripotency are hallmarks of embryonic stem cells (ESCs). However, the signaling pathways that trigger their transition from self-renewal to differentiation remain elusive. Here, we report that calcineurin-NFAT signaling is both necessary and sufficient to switch ESCs from an undifferentiated state to lineage-specific cells and that the inhibition of this pathway can maintain long-term ESC self-renewal independent of leukemia inhibitory factor. Mechanistically, this pathway converges with the Erk1/2 pathway to regulate Src expression and promote the epithelial-mesenchymal transition (EMT), a process required for lineage specification in response to differentiation stimuli. Furthermore, calcineurin-NFAT signaling is activated when the earliest differentiation event occurs in mouse embryos, and its inhibition disrupts extraembryonic lineage development. Collectively, our results demonstrate that the NFAT and Erk1/2 cascades form a signaling switch for early lineage segregation in mouse ESCs and provide significant insights into the regulation of the balance between ESC self-renewal and early lineage specification. Copyright © 2011 Elsevier Inc. All rights reserved.

  4. Mechanisms influencing retrograde flow in the atrioventricular canal during early embryonic cardiogenesis.

    PubMed

    Bulk, Alexander; Bark, David; Johnson, Brennan; Garrity, Deborah; Dasi, Lakshmi Prasad

    2016-10-03

    Normal development of the heart is regulated, in part, by mechanical influences associated with blood flow during early stages of embryogenesis. Specifically, the potential for retrograde flow at the atrioventricular canal (AVC) is particularly important in valve development. However, the mechanisms causing this retrograde flow have received little attention. In this study, a numerical analysis was performed on images of the embryonic zebrafish heart between 48 and 55hpf. During these stages, normal retrograde flow is prevalent. To manipulate this flow, zebrafish were placed in a centrifuge and subjected to a hypergravity environment to alter the cardiac preload at various six-hour intervals between 24 and 48hpf. Parameters of the pumping mechanics were then analyzed through a spatiotemporal analysis of processed image sequences. We find that the loss of retrograde flow in experimentally manipulated embryos occurs in part because of a greater resistance in the form of atrial and AVC contractile closure. Additionally, during retrograde flow, these embryos exhibit significantly greater pressure difference across the AVC based on calculations of expansive and contractile rates of the atrium and ventricle. These results elucidated that the developing heart is highly sensitive to small changes in pumping mechanics as it strives to maintain normal hemodynamic conditions necessary for later cardiac development.

  5. Human embryonic stem cell model of ethanol-mediated early developmental toxicity.

    PubMed

    Nash, Rodney; Krishnamoorthy, Malini; Jenkins, Andrew; Csete, Marie

    2012-03-01

    Fetal alcohol syndrome is an important clinical problem. Human embryonic stem cells (hESC) have not been widely used to study developmental alcohol toxicity. Here we document the phenotype of hESC exposed to clinically-relevant, low dose ethanol (20mM). All cultures were maintained in 3% O2 to reflect normal physiologic conditions. Undifferentiated hESC were expanded with basic fibroblast growth factor (bFGF), with or without ethanol, then differentiated without ethanol. Proliferation and apoptosis in response to ethanol were assayed, and PCR used to examine expression of GABA receptor subunits. Whole cell patch clamping was used to examine GABA(A) receptor function in undifferentiated hESC. Immunocytochemistry and western blotting were used to follow differentiation of early neurons, astrocytes, and oligodendrocytes, Exposure to 20mM ethanol resulted in larger colonies of undifferentiated hESC despite an increase in apoptosis, because proliferation of the undifferentiated cells (and neuroblasts) was significantly increased. Differentiation of hESC (following a week of ethanol exposure) resulted in decreased expression of GFAP (by western) compared to unexposed cells, suggesting that astrocyte differentiation was reduced, while markers of oligodendrocyte and neuron differentiation were unchanged. At the message level, undifferentiated hESC express all GABA(A) receptor subunits, but functional receptors were not found by whole cell patch clamping. Our results in hESC suggest a complex mix of ethanol-induced phenotypic changes when ethanol exposure occurs very early in development. Not only increased apoptosis, but inappropriate proliferation and loss of trophic astrocytes could result from low-dose ethanol exposure very early in development. More generally, these studies support a role for hESC in developing hypotheses and focusing questions to complement animal studies of developmental toxicities. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. NKCC1 cotransporter inactivation underlies embryonic development of chloride-mediated inhibition in mouse spinal motoneuron

    PubMed Central

    Delpy, Alain; Allain, Anne-Emilie; Meyrand, Pierre; Branchereau, Pascal

    2008-01-01

    Early in development, GABA and glycine exert excitatory action that turns to inhibition due to modification of the chloride equilibrium potential (ECl) controlled by the KCC2 and NKCC1 transporters. This switch is thought to be due to a late expression of KCC2 associated with a NKCC1 down-regulation. Here, we show in mouse embryonic spinal cord that both KCC2 and NKCC1 are expressed and functional early in development (E11.5–E13.5) when GABAA receptor activation induces strong excitatory action. After E15.5, a switch occurs rendering GABA unable to provide excitation. At these subsequent stages, NKCC1 becomes both inactive and less abundant in motoneurons while KCC2 remains functional and hyperpolarizes ECl. In conclusion, in contrast to other systems, the cotransporters are concomitantly expressed early in the development of the mouse spinal cord. Moreover, whereas NKCC1 follows a classical functional extinction, KCC2 is highly expressed throughout both early and late embryonic life. PMID:18096599

  7. Influence of temperature and humidity manipulation on chicken embryonic development.

    PubMed

    Noiva, Rute M; Menezes, António C; Peleteiro, Maria C

    2014-10-01

    Temperature and relative humidity (RH) are very important factors affecting embryo development, hatchability, and posthatch performance. This study aimed at characterizing embryonic metabolic and behavioural response to a harsh incubation environment generated by manipulations (elevations and drops) in these two key factors. This study was aimed at establishing patterns of metabolic and behavioural response, as well as mortality and the development of malformations, all of which can potentially be used in monitoring incubating operations and diagnosing problems with faulty equipment. Of all the parameters monitored throughout embryonic development the ones shown to be most affected were: albumen-weight to egg-weight ratio (AR); yolk-weight to egg-weight ratio (YR); embryo-weight to egg-weight ratio (ER); heart rate (HR); voluntary movements per minute (VMM); mortality rates; malformation prevalence and type. The most significant changes in the evolution of AR and YR throughout incubation involved delay and reduction in the amplitude of the expected drop in albumen and yolk levels, reflecting lower nutrient consumption by the embryo. ER tended to grow more slowly and remain lower than the established normal, especially in embryos challenged with temperature treatments. HR and VMM were considered to be strong indicators of embryonic stress, as all treatments applied resulted in elevated heart rate and decreased embryo movement. Mortality rates for both temperature-related treatments were higher during the first four days of incubation. Changes in relative humidity have produced less radical effects on mortality. Malformation rates were higher for embryos subjected to high incubation temperatures and were most prominently related to the abdominal wall, head, skull and limbs. Overall, manipulations in environmental (incubator) temperature during incubation produced more drastic changes in embryo development than humidity-related manipulations, especially where

  8. Brillouin microspectroscopy assessment of tissue differentiation during embryonic development

    NASA Astrophysics Data System (ADS)

    Troyanova-Wood, Maria; Meng, Zhaokai; Silverberg, Hannah; Yakovlev, Vladislav V.

    2017-02-01

    Changes in mechanical properties represent one of the driving factors behind cell differentiation during embryonic development. However, measuring these changes without disrupting the normal progression of morphogenesis or destroying the developing organism is not trivial. Brillouin microspectroscopy has been shown to be capable of nocontact, non-destructive and non-disruptive assessment of elastic properties in developing zebrafish embryos. The present study builds upon the previous work, and observes the changes in elasticity during the development of heart and brain in zebrafish embryos from 8 to 28 hpf (hours post-fertilization) at regular intervals. Brillouin microspectroscopy has proved to be a suitable technique to continuously monitor tissue differentiation and the development of individual organs with high spatial resolution without harming the developing organism.

  9. Angiogenesis is repressed by ethanol exposure during chick embryonic development.

    PubMed

    Wang, Guang; Zhong, Shan; Zhang, Shi-yao; Ma, Zheng-lai; Chen, Jian-long; Lu, Wen-hui; Cheng, Xin; Chuai, Manli; Lee, Kenneth Ka Ho; Lu, Da-xiang; Yang, Xuesong

    2016-05-01

    It is now known that excess alcohol consumption during pregnancy can cause fetal alcohol syndrome to develop. However, it is not known whether excess ethanol exposure could directly affect angiogenesis in the embryo or angiogenesis being indirectly affected because of ethanol-induced fetal alcohol syndrome. Using the chick yolk sac membrane (YSM) model, we demonstrated that ethanol exposure dramatically inhibited angiogenesis in the YSM of 9-day-old chick embryos, in a dose-dependent manner. Likewise, the anti-angiogenesis effect of ethanol could be seen in the developing vessel plexus (at the same extra-embryonic regions) during earlier stages of embryo development. The anti-angiogenic effect of ethanol was found associated with excess reactive oxygen species (ROS) production; as glutathione peroxidase activity increased while superoxide dismutase 1 and 2 activities decreased in the YSMs. We further validated this observation by exposing chick embryos to 2,2'-azobis-amidinopropane dihydrochloride (a ROS inducer) and obtained a similar anti-angiogenesis effect as ethanol treatment. Semiquantitative reverse transcription-polymerase chain reaction analysis of the experimental YSMs revealed that expression of angiogenesis-related genes, vascular endothelial growth factor and its receptor, fibroblast growth factor 2 and hypoxia-inducible factor, were all repressed following ethanol and 2,2'-azobis-amidinopropane dihydrochloride treatment. In summary, our results suggest that excess ethanol exposure inhibits embryonic angiogenesis through promoting superfluous ROS production during embryo development. Copyright © 2015 John Wiley & Sons, Ltd.

  10. The regulation of Dkk1 expression during embryonic development.

    PubMed

    Lieven, Oliver; Knobloch, Jürgen; Rüther, Ulrich

    2010-04-15

    During embryogenesis, the Dkk1 mediated Wnt inhibition controls the spatiotemporal dynamics of cell fate determination, cell differentiation and cell death. Furthermore, the Dkk1 dose is critical for the normal Wnt homeostasis, as alteration of the Dkk1 activity is associated with various diseases. We investigated the regulation of Dkk1 expression during embryonic development. We identified nine conserved non-coding elements (CNEs), located 3' to the Dkk1 locus. Analyses of the regulatory potential revealed that four of these CNEs in combination drive reporter expression very similar to Dkk1 expression in several organs of transgenic embryos. We extended the knowledge of Dkk1 expression during hypophysis, external genitalia and kidney development, suggesting so far to unexplored functions of Dkk1 during the development of these organs. Characterization of the regulatory potential of four individual CNEs revealed that each of these promotes Dkk1 expression in brain and kidney. In combination, two enhancers are responsible for expression in the pituitary and the genital tubercle. Furthermore, individual CNEs mediates craniofacial, optic cup and limb specific Dkk1 regulation. Our study substantially improves the knowledge of Dkk1 regulation during embryonic development and thus might be of high relevance for therapeutic approaches.

  11. Embryonic development of circadian clocks in the mammalian suprachiasmatic nuclei.

    PubMed

    Landgraf, Dominic; Koch, Christiane E; Oster, Henrik

    2014-01-01

    In most species, self-sustained molecular clocks regulate 24-h rhythms of behavior and physiology. In mammals, a circadian pacemaker residing in the hypothalamic suprachiasmatic nucleus (SCN) receives photic signals from the retina and synchronizes subordinate clocks in non-SCN tissues. The emergence of circadian rhythmicity during development has been extensively studied for many years. In mice, neuronal development in the presumptive SCN region of the embryonic hypothalamus occurs on days 12-15 of gestation. Intra-SCN circuits differentiate during the following days and retinal projections reach the SCN, and thus mediate photic entrainment, only after birth. In contrast the genetic components of the clock gene machinery are expressed much earlier and during midgestation SCN explants and isolated neurons are capable of generating molecular oscillations in culture. In vivo metabolic rhythms in the SCN, however, are observed not earlier than the 19th day of rat gestation, and rhythmic expression of clock genes is hardly detectable until after birth. Together these data indicate that cellular coupling and, thus, tissue-wide synchronization of single-cell rhythms, may only develop very late during embryogenesis. In this mini-review we describe the developmental origin of the SCN structure and summarize our current knowledge about the functional initiation and entrainment of the circadian pacemaker during embryonic development.

  12. Quantifying the occurrence of early embryonic mortality on three equine breeding farms

    PubMed Central

    Meyers, Patrick J.; Bonnett, Brenda N.; McKee, Sharyn L.

    1991-01-01

    This prospective field study was designed to describe the incidence of early embryonic mortality (EEM) and factors associated with the cause of EEM on three equine breeding farms in Ontario during the 1989 breeding season. Early embryonic mortality was defined as the loss of a single embryo during the first 40 days of pregnancy (day 0 = day of ovulation or last breeding). Pregnancy diagnoses and subsequent embryonic losses were observed by serial trans-rectal ultrasonography between days 12-20 (PD1) and 21-30 (PD2), and by trans-rectal ultrasonography or palpation per rectum between days 31-40 (PD3). Information on pregnancy status of a mare (or cycle) at 40 days after the last breeding was recorded when available. Nonpregnancy rates were calculated on a per cycle basis, to account for mares with no ultrasonic evidence of an embryo at the initial pregnancy examination. Embryonic mortality rates per cycle were calculated cumulatively (EMR(40)) for the entire 40 day embryonic period and during the specific time periods when a pregnancy diagnosis took place (EMR(PD1), EMR(PD2), EMR(PD3)). Embryonic mortality rates were also calculated on a per mare basis for mares experiencing EEM on either their first (EMR(f)) or any (EMR(a)) breeding cycle. Per cycle mare withdrawal rates were calculated cumulatively for the entire 40 day embryonic period (MWR(40)), and at each specific pregnancy diagnosis time period (MWR(PD1), MWR(PD2), MWR(PD3)) to account for those breeding cycles in which mares were not able to be observed for the entire forty days of the embryonic period. Records from a total of 699 mares involving 1014 breeding cycles were examined and analyzed. Per cycle risk rates for nonpregnancy (NP) were 36.4%, 45.0%, and 22.1%, for farms 1,2 and 3, respectively. Per cycle EMR(40) ranged from 8-17%. Per cycle MWR(40) ranged from 56.5-98.9%, indicative of a high rate of mare withdrawal from the study for the duration of the “embryonic” period. Significant differences

  13. Cadherins in cerebellar development: translation of embryonic patterning into mature functional compartmentalization.

    PubMed

    Redies, Christoph; Neudert, Franziska; Lin, Juntang

    2011-09-01

    Cadherins are cell adhesion molecules with multiple morphogenic functions in brain development, for example, in neuroblast migration and aggregation, axon navigation, neural circuit formation, and synaptogenesis. More than 100 members of the cadherin superfamily are expressed in the developing and mature brain. Most of the cadherins investigated, in particular classic cadherins and δ-protocadherins, are expressed in the cerebellum. For several cadherin subtypes, expression begins at early embryonic stages and persists until mature stages of cerebellar development. At intermediate stages, distinct Purkinje cell clusters exhibit unique rostrocaudal and mediolateral expression profiles for each cadherin. In the chicken, mouse, and other species, the Purkinje cell clusters are separated by intervening raphes of migrating granule cells. This pattern of Purkinje cell clusters/raphes is, at least in part, continuous with the parasagittal striping pattern that is apparent in the mature cerebellar cortex, for example, for zebrin II/aldolase C. Moreover, subregions of the deep cerebellar nuclei, vestibular nuclei and the olivary complex also express cadherins differentially. Neuroanatomical evidence suggests that the nuclear subregions and cortical domains that express the same cadherin subtype are connected to each other, to form neural subcircuits of the cerebellar system. Cadherins thus provide a molecular code that specifies not only embryonic structures but also functional cerebellar compartmentalization. By following the implementation of this code, it can be revealed how mature functional architecture emerges from embryonic patterning during cerebellar development. Dysfunction of some cadherins is associated with psychiatric diseases and developmental impairments and may also affect cerebellar function.

  14. Micro-magnetic resonance imaging study of live quail embryos during embryonic development.

    PubMed

    Duce, Suzanne; Morrison, Fiona; Welten, Monique; Baggott, Glenn; Tickle, Cheryll

    2011-01-01

    Eggs containing live Japanese quail embryos were imaged using micro-magnetic resonance imaging (μMRI) at 24-h intervals from Day 0 to 8, the period during which the main body axis is being laid down and organogenesis is taking place. Considerable detail of non-embryonic structures such as the latebra was revealed at early stages but the embryo could only be visualized around Day 3. Three-dimensional (3D) changes in embryo length and volume were quantified and also changes in volume in the extra- and non-embryonic components. The embryo increased in length by 43% and nearly trebled in volume between Day 4 and Day 5. Although the amount of yolk remained fairly constant over the first 5 days, the amount of albumen decreases significantly and was replaced by extra-embryonic fluid (EEF). ¹H longitudinal (T₁) and transverse (T₂) relaxation times of different regions within the eggs were determined over the first 6 days of development. The T₂ measurements mirrored the changes in image intensity observed, which can be related to the aqueous protein concentrations. In addition, a comparison of the development of Day 0 to 3 quail embryos exposed to radiofrequency (rf) pulses, 7 T static magnetic fields and magnetic field gradients for an average of 7 h with the development of control embryos did not reveal any gross changes, thus confirming that μMRI is a suitable tool for following the development of live avian embryos over time from the earliest stages.

  15. Long-term in vivo study of vertebrate embryonic development using noninvasive harmonics optical microscopy

    NASA Astrophysics Data System (ADS)

    Chen, Szu-Yu; Hsieh, C.-S.; Chu, S.-W.; Lin, Cheng-Yung; Ko, C.-Y.; Chen, Y.-C.; Tsai, Huai-Jen; Hu, C.-H.; Sun, Chi-Kuang

    2005-03-01

    Harmonics optical microscopy (HOM) provides a truly "noninvasive" tool for in vivo and long-term study of vertebrate embryonic development. Based on the nonlinear natures, it provides sub-micrometer 3D spatial resolution and high 3D optical-sectioning power (~1μm axial resolution) without using invasive and toxic fluorophores. Since only virtual-level-transition is involved, HOM is known to leave no energy deposition and no photodamages. Combined with second harmonic generation, which is sensitive to specific structure such as nerve and muscle fibers, HOM can be used to do functional studies of early developmental dynamics of many vertebrate physiological systems. Recently, zebrafish has become a standard model for many biological and medical studies of vertebrates, due to the similarity between embryonic development of zebrafish and human being. Zebrafish embryos now have been used to study many vertebrate physiological systems. We have demonstrated an in vivo HOM study of developmental dynamics of several embryonic physiological systems in live zebrafish embryos, with focuses on the developments of brains, eyes, ears, and hearts. Based on a femtosecond Cr:forsterite laser, which provides the deepest penetration (~1.5mm) and least photodamage in the zebrafish embryo, complete developing processes of different physiological systems within a period of time longer than 20 hours can be non-invasively observed inside the same embryo.

  16. Nicotine alters bovine oocyte meiosis and affects subsequent embryonic development.

    PubMed

    Liu, Ying; Li, Guang-Peng; White, Kenneth L; Rickords, Lee F; Sessions, Benjamin R; Aston, Kenneth I; Bunch, Thomas D

    2007-11-01

    The effects of nicotine on nuclear maturation and meiotic spindle dynamics of bovine oocytes and subsequent embryonic development were investigated. Maturation rates (85%-94%) derived from nicotine treatments at 0.01 to 1.0 mM were similar to the control (86%), but significantly decreased at 2.0 to 6.0 mM. Haploid complements of metaphase II oocytes in 0.01 to 1.0 mM nicotine (approximately 90%) were similar to the control, while lower (ranged from 63% to 76%, P < 0.05 or P < 0.01) haploid oocytes were observed in the 2.0 to 6.0 mM nicotine groups. The majority of the PB1-free oocytes derived from 3.0 to 6.0 mM nicotine treatments were diploidy (2n = 60). Spindle microtubules changed from characteristically being asymmetrical in the controls to being equally distributed into two separate chromosome groups in the nicotine treatments. Nicotine disorganized the microfilament organization and inhibited the movement of anaphase or telophase chromosomes to the cortical area. The inhibited two chromosome groups became two spindles that either moved close in proximity or merged entirely together resulting in diploidy within the affected oocyte. Nicotine treatment significantly reduced the rate of cleavage and blastocyst development after parthenogenetic activation. Diploidy and cell number were drastically reduced in the resultant blastocysts. In conclusion, nicotine can alter the normal process of bovine oocyte meiosis and affects subsequent embryonic development.

  17. Embryonic and postnatal development of GABA, calbindin, calretinin, and parvalbumin in the mouse claustral complex.

    PubMed

    Dávila, José Carlos; Real, M Angeles; Olmos, Luis; Legaz, Isabel; Medina, Loreta; Guirado, Salvador

    2005-01-03

    We analyzed the development of immunoreactive expression patterns for the neurotransmitter gamma-aminobutyric acid (GABA) and the calcium-binding proteins calbindin, calretinin, and parvalbumin in the embryonic and postnatal mouse claustral complex. Each calcium-binding protein shows a different temporal and spatial pattern of development. Calbindin-positive cells start to be seen very early during embryogenesis and increase dramatically until birth, thus becoming the most abundant cell type during embryonic development, especially in the ventral pallial part of the claustrum. The distribution of calbindin neurons throughout the claustrum during embryonic development partly parallels that of GABA neurons, suggesting that at least part of the calbindin neurons of the claustral complex are GABAergic and originate in the subpallium. Parvalbumin cells, on the other hand, start to be seen only postnatally, and their number then increases while the density of calbindin neurons decreases. Based on calretinin expression in axons, the core/shell compartments of the dorsal claustrum start to be clearly seen at embryonic day 18.5 and may be related to the development of the thalamoclaustral input. Comparison with the expression of Cadherin 8, a marker of the developing dorsolateral claustrum, indicates that the core includes a central part of the dorsolateral claustrum, whereas the shell includes a peripheral area of the dorsolateral claustrum, plus the adjacent ventromedial claustrum. The present data on the spatiotemporal developmental patterns of several subtypes of GABAergic neurons in the claustral complex may help for future studies on temporal lobe epilepsies, which have been related to an alteration of the GABAergic activity.

  18. Approach to quantify two-dimensional strain of chick embryonic heart in early stage based on spectral domain optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Zhao, Yuqian; Dou, Shidan; Zhu, Wenlong; Wang, Yi; Xu, Tao; Wang, Fengwen; Ma, Zhenhe

    2015-03-01

    The heart undergoes remarkable changes during embryonic development due to genetic programming and epigenetic influences, in which mechanical loads is a key factor. As embryonic research development, an important goal is to develop mathematical models that describe the influence of mechanics on embryonic heart development. However, basic parameters for the modeling are difficult to acquire since the embryonic heart is tiny and beating fast in the early stages. Optical coherence tomography (OCT) technique provides depth-resolved image with high resolution and high acquisition speed in a noninvasive manner. In this paper, we performed 4D[(x,y,z) + t] scan on the outflow tract (OFT) of the chick embryonic heart at stage of HH18(~ 3 days of incubation) in vivo using spectral domain OCT (SDOCT). Parameters such as displacement and geometrical size of the OFT were extracted from the structural images of the SDOCT. Two-dimensional strain vector were solved using strain-displacement relations in curvilinear cylindrical coordinates based on kinetic theory of elasticity. Based on the geometrical size and other initial conditions, two-dimensional elasticity finite element model of the OFT myocardial wall deformation were established and then solved by direct frequency response method. Comparison between experimental data and simulation result shows the utility of the finite element models. Our results demonstrate that mathematical modeling based on parameters provided by SDOCT is a useful approach for studying cardiac development in early stage.

  19. [Establishment of sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo].

    PubMed

    Jiang, Hua; Feng, You-Ji; Xie, Yi; Han, Jin-Lan; Wang, Zack; Chen, Tong

    2008-10-14

    To establish a sprouting embryoid body model mimicking early embryonic vasculogenesis in human embryo. Human embryonic stem were (hESCs) were cultured on the mouse embryo fibroblasts and then were induced to differentiate to form three-dimensional EB. The hEBs were cultured in media containing various angiogenesis-related factors: vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), endostatin, angiostatin, and platelet factor (PF)-4 of different concentrations for 3 days to observe the sprouting of the hEBs. 3, 3, 3', 3'-tetramethylindo-carbocyanine perchlorate labeled acetylated low density lipoprotein (Dil-AcLDL) was added onto the hEBs foe 4 h Immunofluorescence assay was used to observe if Dil-AcLDL was absorbed and if CD31 was expressed so as to determine the existence of embryonic endothelial cells in the sprouting structures. The ideal culturing condition was analyzed. The differentiated EBs formed sprouting structures in the collagen I matrix containing VEGF and FGF. The sprouts among individual EBs were able to link to each other and form vascular network-like structures. In the presence of VEGF and FGF, the sprouts branching from the EBs assimilated Dil-AcLDL, expressed CD31 and formed a 3-dimensional cylindrical organization. The concentrations of growth factors ideally stimulating sprouting growth were 100 ng/ml of VEGF and 50 ng/ml of FGF. The networks among the EBs were abolished by the angiostatin, endostatin, and PF4. The sprouting from hEBs accumulates embryonic endothelial cells and the sprouting network-like structures are indeed endothelial in nature. Inducing of sprouting EBs is an ideal model that mimics early embryonic vasculogenesis in humans.

  20. GLUT1 deficiency links nutrient availability and apoptosis during embryonic development.

    PubMed

    Jensen, Penny J; Gitlin, Jonathan D; Carayannopoulos, Mary O

    2006-05-12

    GLUT1 is essential for human brain development and function, as evidenced by the severe epileptic encephalopathy observed in children with GLUT1 deficiency syndrome resulting from inherited loss-of-function mutations in the gene encoding this facilitative glucose transporter. To further elucidate the pathophysiology of this disorder, the zebrafish orthologue of human GLUT1 was identified, and expression of this gene was abrogated during early embryonic development, resulting in a phenotype of aberrant brain organogenesis consistent with the observed expression of Glut1 in the embryonic tectum and specifically rescued by human GLUT1 mRNA. Affected embryos displayed impaired glucose uptake concomitant with increased neural cell apoptosis and subsequent ventricle enlargement, trigeminal ganglion cell loss, and abnormal hindbrain architecture. Strikingly, inhibiting expression of the zebrafish orthologue of the proapoptotic protein Bad resulted in complete rescue of this phenotype, and this occurred even in the absence of restoration of apparent glucose uptake. Taken together, these studies describe a tractable system for elucidating the cellular and molecular mechanisms of Glut1 deficiency and provide compelling in vivo genetic evidence directly linking nutrient availability and activation of mitochondria-dependent apoptotic mechanisms during embryonic brain development.

  1. De Novo Assembly and Characterization of Early Embryonic Transcriptome of the Horseshoe Crab Tachypleus tridentatus.

    PubMed

    Chen, Mingliang; Wang, Chenying; Wang, Wei; Ji, Gubiao; Hu, Bin; Du, Mi; Liu, Guosheng; Li, Zengpeng; Wang, Weiyi; Lin, Xiangzhi; Zheng, Weibing; Chen, Jianming

    2016-01-01

    The horseshoe crab Tachypleus tridentatus is a unique marine species and a potential model for marine invertebrate. Limited genomic and transcriptional data are currently available to understand the molecular mechanisms underlying the embryonic development of T. tridentatus. Here, we reported for the first time the de novo transcriptome assembly for T. tridentatus at embryonic developmental stage using Illumina RNA-seq platform. Approximate 38 million reads were obtained and further assembled into 133,212 unigenes. Sequence homology analysis against public databases revealed that 33,796 unigenes could be annotated with gene descriptions. Of the annotated unigenes, we identified a number of key components of several conserved metazoan signaling pathways (Hedgehog, Wnt, TGF-beta and Notch pathways) and other important regulatory genes involved in embryonic development. Targeted searching of Pax family genes which play critical roles in the formation of tissue and organ during embryonic development identified a complete set of Pax family genes. Moreover, the full length T. tridentatus Pax1/9a (TtPax1/9a) and Pax1/9b (TtPax1/9b) cDNA sequences were determined based on the transcriptome, demonstrating the immediate application of our database. Using quantitative real time PCR, we analyzed the expression patterns of TtPax1/9a and TtPax1/9b in different tissues of horseshoe crab. Taking advantage of Drosophila model, we further found that TtPax1/9b, but not TtPax1/9a, can partly rescue the Drosophila homolog Poxm dysfunction-caused lethality at the larval stage. Our study provides the embryonic transcriptome of T. tridentatus which could be immediately used for gene discovery and characterization, functional genomics studies in T. tridentatus. This transcriptome database will also facilitate the investigations of molecular mechanisms underlying embryonic development of T. tridentatus and other marine arthropods as well.

  2. De Novo Assembly and Characterization of Early Embryonic Transcriptome of the Horseshoe Crab Tachypleus tridentatus

    PubMed Central

    Ji, Gubiao; Hu, Bin; Du, Mi; Liu, Guosheng; Li, Zengpeng; Wang, Weiyi; Lin, Xiangzhi; Zheng, Weibing; Chen, Jianming

    2016-01-01

    The horseshoe crab Tachypleus tridentatus is a unique marine species and a potential model for marine invertebrate. Limited genomic and transcriptional data are currently available to understand the molecular mechanisms underlying the embryonic development of T. tridentatus. Here, we reported for the first time the de novo transcriptome assembly for T. tridentatus at embryonic developmental stage using Illumina RNA-seq platform. Approximate 38 million reads were obtained and further assembled into 133,212 unigenes. Sequence homology analysis against public databases revealed that 33,796 unigenes could be annotated with gene descriptions. Of the annotated unigenes, we identified a number of key components of several conserved metazoan signaling pathways (Hedgehog, Wnt, TGF-beta and Notch pathways) and other important regulatory genes involved in embryonic development. Targeted searching of Pax family genes which play critical roles in the formation of tissue and organ during embryonic development identified a complete set of Pax family genes. Moreover, the full length T. tridentatus Pax1/9a (TtPax1/9a) and Pax1/9b (TtPax1/9b) cDNA sequences were determined based on the transcriptome, demonstrating the immediate application of our database. Using quantitative real time PCR, we analyzed the expression patterns of TtPax1/9a and TtPax1/9b in different tissues of horseshoe crab. Taking advantage of Drosophila model, we further found that TtPax1/9b, but not TtPax1/9a, can partly rescue the Drosophila homolog Poxm dysfunction-caused lethality at the larval stage. Our study provides the embryonic transcriptome of T. tridentatus which could be immediately used for gene discovery and characterization, functional genomics studies in T. tridentatus. This transcriptome database will also facilitate the investigations of molecular mechanisms underlying embryonic development of T. tridentatus and other marine arthropods as well. PMID:26731763

  3. A novel approach for studying the temporal modulation of embryonic skeletal development using organotypic bone cultures and microcomputed tomography.

    PubMed

    Kanczler, Janos M; Smith, Emma L; Roberts, Carol A; Oreffo, Richard O C

    2012-10-01

    Understanding the structural development of embryonic bone in a three dimensional framework is fundamental to developing new strategies for the recapitulation of bone tissue in latter life. We present an innovative combined approach of an organotypic embryonic femur culture model, microcomputed tomography (μCT) and immunohistochemistry to examine the development and modulation of the three dimensional structures of the developing embryonic femur. Isolated embryonic chick femurs were organotypic (air/liquid interface) cultured for 10 days in either basal, chondrogenic, or osteogenic supplemented culture conditions. The growth development and modulating effects of basal, chondrogenic, or osteogenic culture media of the embryonic chick femurs was investigated using μCT, immunohistochemistry, and histology. The growth and development of noncultured embryonic chick femur stages E10, E11, E12, E13, E15, and E17 were very closely correlated with increased morphometric indices of bone formation as determined by μCT. After 10 days in the organotpyic culture set up, the early aged femurs (E10 and E11) demonstrated a dramatic response to the chondrogenic or osteogenic culture conditions compared to the basal cultured femurs as determined by a change in μCT morphometric indices and modified expression of chondrogenic and osteogenic markers. Although the later aged femurs (E12 and E13) increased in size and structure after 10 days organotpypic culture, the effects of the osteogenic and chondrogenic organotypic cultures on these femurs were not significantly altered compared to basal conditions. We have demonstrated that the embryonic chick femur organotpyic culture model combined with the μCT and immunohistochemical analysis can provide an integral methodology for investigating the modulation of bone development in an ex vivo culture setting. Hence, these interdisciplinary techniques of μCT and whole organ bone cultures will enable us to delineate some of the temporal

  4. A Novel Approach for Studying the Temporal Modulation of Embryonic Skeletal Development Using Organotypic Bone Cultures and Microcomputed Tomography

    PubMed Central

    Smith, Emma L.; Roberts, Carol A.

    2012-01-01

    Understanding the structural development of embryonic bone in a three dimensional framework is fundamental to developing new strategies for the recapitulation of bone tissue in latter life. We present an innovative combined approach of an organotypic embryonic femur culture model, microcomputed tomography (μCT) and immunohistochemistry to examine the development and modulation of the three dimensional structures of the developing embryonic femur. Isolated embryonic chick femurs were organotypic (air/liquid interface) cultured for 10 days in either basal, chondrogenic, or osteogenic supplemented culture conditions. The growth development and modulating effects of basal, chondrogenic, or osteogenic culture media of the embryonic chick femurs was investigated using μCT, immunohistochemistry, and histology. The growth and development of noncultured embryonic chick femur stages E10, E11, E12, E13, E15, and E17 were very closely correlated with increased morphometric indices of bone formation as determined by μCT. After 10 days in the organotpyic culture set up, the early aged femurs (E10 and E11) demonstrated a dramatic response to the chondrogenic or osteogenic culture conditions compared to the basal cultured femurs as determined by a change in μCT morphometric indices and modified expression of chondrogenic and osteogenic markers. Although the later aged femurs (E12 and E13) increased in size and structure after 10 days organotpypic culture, the effects of the osteogenic and chondrogenic organotypic cultures on these femurs were not significantly altered compared to basal conditions. We have demonstrated that the embryonic chick femur organotpyic culture model combined with the μCT and immunohistochemical analysis can provide an integral methodology for investigating the modulation of bone development in an ex vivo culture setting. Hence, these interdisciplinary techniques of μCT and whole organ bone cultures will enable us to delineate some of the temporal

  5. Identification of estrogen target genes during zebrafish embryonic development through transcriptomic analysis.

    PubMed

    Hao, Ruixin; Bondesson, Maria; Singh, Amar V; Riu, Anne; McCollum, Catherine W; Knudsen, Thomas B; Gorelick, Daniel A; Gustafsson, Jan-Åke

    2013-01-01

    Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post fertilization (dpf), harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP)). Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database). The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific.

  6. Identification of Estrogen Target Genes during Zebrafish Embryonic Development through Transcriptomic Analysis

    PubMed Central

    Hao, Ruixin; Bondesson, Maria; Singh, Amar V.; Riu, Anne; McCollum, Catherine W.; Knudsen, Thomas B.; Gorelick, Daniel A.; Gustafsson, Jan-Åke

    2013-01-01

    Estrogen signaling is important for vertebrate embryonic development. Here we have used zebrafish (Danio rerio) as a vertebrate model to analyze estrogen signaling during development. Zebrafish embryos were exposed to 1 µM 17β-estradiol (E2) or vehicle from 3 hours to 4 days post fertilization (dpf), harvested at 1, 2, 3 and 4 dpf, and subjected to RNA extraction for transcriptome analysis using microarrays. Differentially expressed genes by E2-treatment were analyzed with hierarchical clustering followed by biological process and tissue enrichment analysis. Markedly distinct sets of genes were up and down-regulated by E2 at the four different time points. Among these genes, only the well-known estrogenic marker vtg1 was co-regulated at all time points. Despite this, the biological functional categories targeted by E2 were relatively similar throughout zebrafish development. According to knowledge-based tissue enrichment, estrogen responsive genes were clustered mainly in the liver, pancreas and brain. This was in line with the developmental dynamics of estrogen-target tissues that were visualized using transgenic zebrafish containing estrogen responsive elements driving the expression of GFP (Tg(5xERE:GFP)). Finally, the identified embryonic estrogen-responsive genes were compared to already published estrogen-responsive genes identified in male adult zebrafish (Gene Expression Omnibus database). The expressions of a few genes were co-regulated by E2 in both embryonic and adult zebrafish. These could potentially be used as estrogenic biomarkers for exposure to estrogens or estrogenic endocrine disruptors in zebrafish. In conclusion, our data suggests that estrogen effects on early embryonic zebrafish development are stage- and tissue- specific. PMID:24223173

  7. Embryonic development and inviability phenotype of chicken-Japanese quail F1 hybrids

    PubMed Central

    Ishishita, Satoshi; Kinoshita, Keiji; Nakano, Mikiharu; Matsuda, Yoichi

    2016-01-01

    Interspecific hybrid incompatibility, including inviability and sterility, is important in speciation; however, its genetic basis remains largely unknown in vertebrates. Crosses between male chickens and female Japanese quails using artificial insemination can generate intergeneric hybrids; however, the hatching rate is low, and hatched hybrids are only sterile males. Hybrid development is arrested frequently during the early embryonic stages, and the sex ratio of living embryos is male-biased. However, the development and sex ratio of hybrid embryos have not been comprehensively analyzed. In the present study, we observed delayed embryonic development of chicken-quail hybrids during the early stage, compared with that of chickens and quails. The survival rate of hybrids decreased markedly during the blastoderm-to-pre-circulation stage and then decreased gradually through the subsequent stages. Hybrid females were observed at more than 10 d of incubation; however, the sex ratio of hybrids became male-biased from 10 d of incubation. Severely malformed embryos were observed frequently in hybrids. These results suggest that developmental arrest occurs at various stages in hybrid embryos, including a sexually non-biased arrest during the early stage and a female-biased arrest during the late stage. We discuss the genetic basis for hybrid inviability and its sex bias. PMID:27199007

  8. Ectodysplasin receptor-mediated signaling is essential for embryonic submandibular salivary gland development.

    PubMed

    Jaskoll, Tina; Zhou, Yan-Min; Trump, Gary; Melnick, Michael

    2003-04-01

    Hypohidrotic (anhidrotic) ectodermal dysplasia (HED), the most common of the approximately 150 described ectodermal dysplasias, is a disorder characterized by abnormal hair, teeth, sweat glands, and salivary glands. Mutations in the EDA (ectodysplasin-A) and EDAR (ectodysplasin-A receptor) genes are responsible for X-linked and autosomal HED, respectively. Abnormal phenotypes similar to HED are seen in Tabby (Eda(Ta)) and downless (Edar(dl)) mutant mice. Although recent studies have focused on the role of Eda/Edar signaling during hair and tooth development, very little is known about its role during embryonic submandibular salivary gland (SMG) development. To this end, we analyzed the SMG phenotypes in Tabby (Ta) and downless (dl) mutant mice and determined that Ta SMGs are hypoplastic, whereas dl SMGs are severely dysplastic. The absence of SMG ducts and acini in dl SMGs suggests that Eda/Edar signaling is essential for lumina formation and glandular histodifferentiation. Our localization of Eda and Edar proteins at sites of lumen and acini formation supports this conclusion. Moreover, the presence of SMGs in both Ta and dl mutant mice, as well as the absence of immunodetectable Eda and Edar protein in Initial Bud and Early Pseudoglandular stage SMGs, indicate that Eda/Edar-mediated signaling is important for branching morphogenesis and histodifferentiation, but not for initial gland formation. To initially delineate the morphoregulatory role of Eda/Edar-mediated signaling during embryonic SMG development, we cultured embryonic day 14 SMGs with enhanced or abrogated Eda/Edar signaling. Eda supplementation induced a significant increase in SMG branching, and enhanced activation of NF-kappaB. Abrogating Eda/Edar signaling by adding the soluble form of Edar to bind endogenous ligand in embryonic SMGs results in a significant dose-dependent decrease in branching morphogenesis. Taken together, our results suggest that the Eda/Edar/NF-kappaB pathway exerts its effect

  9. Storage of eggs in water affects internal egg quality, embryonic development, and hatchling quality.

    PubMed

    van den Brand, H; Reijrink, I A M; Hoekstra, L A; Kemp, B

    2008-11-01

    In a series of experiments, effects of storage of eggs in water on internal egg quality, embryonic development, and hatchling quality were investigated. In experiment 1, unfertilized eggs were stored for 4 to 14 d in water (W) or air (control; C). In experiment 2, fertilized eggs were stored for 3 to 14 d in water or air and thereafter incubated for 9 d. In experiment 3, eggs were stored for 16 d in water or air and incubated for 1 to 9 d thereafter. In experiment 4, eggs were stored for 14 d in water or air, incubated thereafter, and hatching time and hatchling quality were determined. In all experiments, egg weight loss in the C treatment increased with duration of storage, whereas W eggs gained weight during storage. Albumen and yolk pH after storage and during incubation were greater in the C eggs compared with the W eggs. In experiment 3, embryonic development at d 4 and 9 was advanced in the W eggs compared with the C eggs. In experiment 4, the number of viable embryonic cells after storage and after trypsinization was lower in the C treatment than in the W treatment (30,188 vs. 69,618; P < 0.001). Hatching time was postponed in the W treatment compared with the C treatment (501 vs. 495 h; P < 0.05). Hatchling length was greater in the C treatment (19.7 vs. 20.3 cm; P = 0.01), and residual yolk was less in the C treatment than in the W treatment (4.9 vs. 8.3 g; P < 0.001). We concluded that storage of eggs in water for a prolonged period positively affects internal egg characteristics and early embryonic development, but negatively affects hatchling quality. The reason for the loss of the head start with progressing incubation needs further investigation.

  10. Embryonic development period and the prevalence of avian blood parasites.

    PubMed Central

    Ricklefs, R E

    1992-01-01

    Variation in prevalence of avian hematozoa is related to taxonomic affiliation at the level of the family or subfamily but not of the genus within families. Prevalence is comparatively insensitive to the influences of habitat and season; however, temperate species have higher incidences of infection than tropical species belonging to the same families. Among taxa of nonraptorial altricial landbirds, hematozoan prevalence is inversely related to the length of the incubation period but shows little relationship to body size and rate of postnatal development. This finding suggests a possible link between the duration of embryonic development and the ability to resist or control infection, possibly due to maturational processes in the avian immune system. PMID:1584808

  11. [Development of human embryonic stem cell model for toxicity evaluation].

    PubMed

    Yu, Guang-yan; Cao, Tong; Ouyang, Hong-wei; Peng, Shuang-qing; Deng, Xu-liang; Li, Sheng-lin; Liu, He; Zou, Xiao-hui; Fu, Xin; Peng, Hui; Wang, Xiao-ying; Zhan, Yuan

    2013-02-18

    The current international standard for toxicity screening of biomedical devices and materials recommend the use of immortalized cell lines because of their homogeneous morphologies and infinite proliferation which provide good reproducibility for in vitro cytotoxicity screening. However, most of the widely used immortalized cell lines are derived from animals and may not be representative of normal human cell behavior in vivo, in particular in terms of the cytotoxic and genotoxic response. Therefore, It is vital to develop a model for toxicity evaluation. In our studies, two Chinese human embryonic stem cell (hESC) lines as toxicity model were established. hESC derived tissue/organ cell model for tissue/organ specific toxicity evaluation were developed. The efficiency and accuracy of using hESC model for cytoxicity, embryotoxicity and genotoxicity evaluation were confirmed. The results indicated that hESCs might be good tools for toxicity testing and biosafety evaluation in vitro.

  12. Characterization of tweety gene (ttyh1-3) expression in Xenopus laevis during embryonic development

    PubMed Central

    Rabe, Brian A.; Huyck, Ryan W.; Williams, Cheyenne C.; Saha, Margaret S.

    2015-01-01

    The tweety family of genes encodes large-conductance chloride channels and has been implicated in a wide array of cellular processes including cell division, cell adhesion, regulation of calcium activity, and tumorigenesis, particularly in neuronal cells. However, their expression patterns during early development remain largely unknown. Here, we describe the spatial and temporal patterning of ttyh1, ttyh2, and ttyh3 in Xenopus laevis during early embryonic development. Ttyh1 and ttyh3 are initially expressed at the late neurula stage are and primarily localized to the developing nervous system; however ttyh1 and ttyh3 both show transient expression in the somites. By swimming tadpole stages, all three genes are expressed in the brain, spinal cord, eye, and cranial ganglia. While ttyh1 is restricted to proliferative, ventricular zones, ttyh3 is primarily localized to postmitotic regions of the developing nervous system. Ttyh2, however, is strongly expressed in cranial ganglia V, VII, IX and X. The differing temporal and spatial expression patterns of ttyh1, ttyh2, and ttyh3 suggest that they may play distinct roles throughout embryonic development. PMID:25541457

  13. Fucoidan Promotes Early Step of Cardiac Differentiation from Human Embryonic Stem Cells and Long-Term Maintenance of Beating Areas

    PubMed Central

    Hamidi, Sofiane; Letourneur, Didier; Aid-Launais, Rachida; Di Stefano, Antonio; Vainchenker, William; Norol, Françoise

    2014-01-01

    Somatic stem cells require specific niches and three-dimensional scaffolds provide ways to mimic this microenvironment. Here, we studied a scaffold based on Fucoidan, a sulfated polysaccharide known to influence morphogen gradients during embryonic development, to support human embryonic stem cells (hESCs) differentiation toward the cardiac lineage. A macroporous (pore 200 μm) Fucoidan scaffold was selected to support hESCs attachment and proliferation. Using a protocol based on the cardiogenic morphogen bone morphogenic protein 2 (BMP2) and transforming growth factor (TGFβ) followed by tumor necrosis factor (TNFα), an effector of cardiopoietic priming, we examined the cardiac differentiation in the scaffold compared to culture dishes and embryoid bodies (EBs). At day 8, Fucoidan scaffolds supported a significantly higher expression of the 3 genes encoding for transcription factors marking the early step of embryonic cardiac differentiation NKX2.5 (p<0.05), MEF2C (p<0.01), and GATA4 (p<0.01), confirmed by flow cytometry analysis for MEF2C and NKX2.5. The ability of Fucoidan scaffolds to locally concentrate and slowly release TGFβ and TNFα was confirmed by Luminex technology. We also found that Fucoidan scaffolds supported the late stage of embryonic cardiac differentiation marked by a significantly higher atrial natriuretic factor (ANF) expression (p<0.001), although only rare beating areas were observed. We postulated that absence of mechanical stress in the soft hydrogel impaired sarcomere formation, as confirmed by molecular analysis of the cardiac muscle myosin MYH6 and immunohistological staining of sarcomeric α-actinin. Nevertheless, Fucoidan scaffolds contributed to the development of thin filaments connecting beating areas through promotion of smooth muscle cells, thus enabling maintenance of beating areas for up to 6 months. In conclusion, Fucoidan scaffolds appear as a very promising biomaterial to control cardiac differentiation from hESCs that

  14. Early Program Development

    NASA Image and Video Library

    2004-04-15

    During the Space Shuttle development phase, Marshall plarners concluded a Heavy Lift Launch Vehicle (HLLV) would be needed for successful Space Industrialization. Shown here in this 1976's artist's conception is an early version of the HLLV during launch.

  15. Histone demethylase JMJD5 is essential for embryonic development

    SciTech Connect

    Oh, Sangphil; Janknecht, Ralf

    2012-03-30

    Highlights: Black-Right-Pointing-Pointer Histone demethylase JMJD5 is essential for embryogenesis. Black-Right-Pointing-Pointer Transcription of tumor suppressor p53 is upregulated in JMJD5 knockout embryos. Black-Right-Pointing-Pointer JMJD5 may antagonize p53-dependent growth inhibition and apoptosis. Black-Right-Pointing-Pointer JMJD5 is overexpressed in leukemias and breast cancer. -- Abstract: Histone lysine methylation is pivotal in regulating chromatin structure and thus profoundly affects the transcriptome. JMJD5 (jumonji C domain-containing 5) is a histone demethylase that specifically removes methyl moieties from dimethylated lysine 36 on histone H3 and exerts a pro-proliferative effect on breast cancer cells. Here, we generated JMJD5 knockout mice in order to study the physiological significance of this enzyme. Whereas heterozygous knockout mice displayed no overt phenotype, homozygous JMJD5 knockouts died around day 10 of embryonal development. JMJD5{sup -/-} embryos showed delayed development already at E8.5 and were actively resorbed at E10.5. While strong JMJD5 expression was observed only in the yolk sac at E8.5, JMJD5 was robustly expressed in E10.5 embryos at several sites, including the heart and eye. Lack of JMJD5 resulted in transcriptional upregulation of the tumor suppressor p53. Concurrently, the cell cycle inhibitor p21 and the pro-apoptotic molecule Noxa, both of which are prominent p53 target genes, became strongly upregulated in JMJD5{sup -/-} embryos. Collectively, our data indicate that JMJD5 is essential during embryonal development and a repressor of p53 expression. The latter suggests that JMJD5 has oncogenic activity and accordingly JMJD5 is upregulated in leukemias and breast cancer.

  16. Specialized mouse embryonic stem cells for studying vascular development.

    PubMed

    Glaser, Drew E; Burns, Andrew B; Hatano, Rachel; Medrzycki, Magdalena; Fan, Yuhong; McCloskey, Kara E

    2014-01-01

    Vascular progenitor cells are desirable in a variety of therapeutic strategies; however, the lineage commitment of endothelial and smooth muscle cell from a common progenitor is not well-understood. Here, we report the generation of the first dual reporter mouse embryonic stem cell (mESC) lines designed to facilitate the study of vascular endothelial and smooth muscle development in vitro. These mESC lines express green fluorescent protein (GFP) under the endothelial promoter, Tie-2, and Discomsoma sp. red fluorescent protein (RFP) under the promoter for alpha-smooth muscle actin (α-SMA). The lines were then characterized for morphology, marker expression, and pluripotency. The mESC colonies were found to exhibit dome-shaped morphology, alkaline phosphotase activity, as well as expression of Oct 3/4 and stage-specific embryonic antigen-1. The mESC colonies were also found to display normal karyotypes and are able to generate cells from all three germ layers, verifying pluripotency. Tissue staining confirmed the coexpression of VE (vascular endothelial)-cadherin with the Tie-2 GFP+ expression on endothelial structures and smooth muscle myosin heavy chain with the α-SMA RFP+ smooth muscle cells. Lastly, it was verified that the developing mESC do express Tie-2 GFP+ and α-SMA RFP+ cells during differentiation and that the GFP+ cells colocalize with the vascular-like structures surrounded by α-SMA-RFP cells. These dual reporter vascular-specific mESC permit visualization and cell tracking of individual endothelial and smooth muscle cells over time and in multiple dimensions, a powerful new tool for studying vascular development in real time.

  17. Effects of simulated microgravity on mammalian fertilization and preimplantation embryonic development in vitro.

    PubMed

    Kojima, Y; Sasaki, S; Kubota, Y; Ikeuchi, T; Hayashi, Y; Kohri, K

    2000-12-01

    To study the effects of simulated microgravity on mammalian fertilization and preimplantation embryonic development in vitro with the use of a horizontal clinostat device. Controlled animal study. Research laboratory at a university medical school. B6D2F1 (C57BL/6 x DBA/2) and ICR mice between 8 and 10 weeks old. The first experiment was performed to investigate whether gravity is required for fertilization in vitro under three conditions: clinostat rotation, rotational control, and stationary control. In the second experiment, one-cell embryos were cultured under each condition and their morphology and viability were assessed at 96 hours. The fertilized numbers and embryonic numbers at the morula and blastocyst stages were recorded in each condition. In the first experiment, there were no statistically significant differences in the efficiency of achieving normal fertilization in vitro among the conditions. In the second experiment, there was a statistically significant decrease in the number of embryos reaching the morula and blastocyst stages after 96 hours in culture under clinostat rotation. These results suggest that the process of fertilization in vitro is not sensitive to the gravitational vector. However, the possibility exists that the frequency of early embryonic lethality is increased by microgravity.

  18. Temporal regulation of mRNAs for select bone morphogenetic proteins (BMP), BMP receptors and their associated SMAD proteins during bovine early embryonic development: effects of exogenous BMP2 on embryo developmental progression

    PubMed Central

    2014-01-01

    Background We previously demonstrated embryotrophic actions of maternal (oocyte-derived) follistatin during bovine early embryogenesis. Classical actions of follistatin are attributed to inhibition of activity of growth factors including activins and bone morphogenetic proteins (BMP). However, temporal changes in BMP mRNA in early bovine embryos and the effects of exogenous BMP on embryo developmental progression are not understood. The objectives of present studies were to characterize mRNA abundance for select BMP, BMP receptors and BMP receptor associated SMADs during bovine oocyte maturation and early embryogenesis and determine effects of addition of exogenous BMP protein on early development. Methods Relative abundance of mRNA for BMP2, BMP3, BMP7, BMP10, SMAD1, SMAD5, ALK3, ALK6, ALK2, BMPR2, ACVR2A and ACVR2B was determined by RT-qPCR analysis of germinal vesicle (GV) and in vitro matured metaphase II (MII) oocytes and in vitro produced embryos collected at pronuclear, 2-cell (C), 4C, 8C, 16C, morula and blastocyst stages. Effects of addition of recombinant human BMP2 (0, 1, 10 and 100 ng/ml) during initial 72 h of embryo culture on early cleavage (within 30 h post insemination), total cleavage, development to 8C-16C and blastocyst stages and blastocyst mRNA abundance for markers of inner cell mass (NANOG) and trophectoderm (CDX2) were also determined. Results Abundance of mRNA for BMP2, BMP10, SMAD1, SMAD5, ALK3, ALK2, BMPR2 and ACVR2B was elevated in MII oocytes and/or pronuclear stage embryos (relative to GV) and remained elevated through the 8C -16C stages, whereas BMP3, BMP7 and ALK2 mRNAs were transiently elevated. Culture of embryos to the 8C stage in the presence of α-amanitin resulted in increased abundance for all of above transcripts examined relative to untreated 8C embryos. Effects of addition of exogenous BMP2 on early cleavage rates and rates of development to 8C-16C and blastocyst stages were not observed, but BMP2 treatment increased

  19. Volumetric optical mapping in early embryonic hearts using light-sheet microscopy

    PubMed Central

    Ma, Pei; Chan, Dennis C.; Gu, Shi; Watanabe, Michiko; Jenkins, Michael W.; Rollins, Andrew M.

    2016-01-01

    Optical mapping (OM) of electrical activity using voltage-sensitive fluorescent dyes is a powerful tool for the investigation of embryonic cardiac electrophysiology. However, because conventional OM integrates the signal in depth and projects it to a two-dimensional plane, information acquired is incomplete and dependent upon the orientation of the sample. This complicates interpretation of data, especially when comparing one heart to another. To overcome this limitation, we present volumetric OM using light-sheet microscopy, which enables high-speed capture of optically sectioned slices. Voltage-sensitive fluorescence images from multiple planes across entire early embryonic quail hearts were acquired, and complete, orientation-independent, four-dimensional maps of transmembrane potential are demonstrated. Volumetric OM data were collected while using optical pacing to control the heart rate, paving the way for physiological measurements and precise manipulation of the heartbeat in the future. PMID:28018729

  20. Expression of Maternally and Embryonically Derived Hypoxanthine Phosphoribosyl Transferase (Hprt) Activity in Mouse Eggs and Early Embryos

    PubMed Central

    Kratzer, Paul G.

    1983-01-01

    X-chromosome activity in early mouse development has been studied by a gene dosage method that involves measuring the activity level of the X-linked enzyme hypoxanthine phosphoribosyl transferase (HPRT) in single eggs and embryos from XO females and from females heterozygous for In(X)1H, a paracentric inversion of the X chromosome. The HPRT activity in oocytes increased threefold over a 24-hr period beginning after ovulation. Afterward, the activity plateaued in unfertilized eggs but continued to increase for at least 66 hr in presumed OY embryos. Both before and after ovulation, the level of activity in unfertilized eggs from In(X)/X females was twice that from XO females, and the distributions of activity in eggs for both sets of females remained unimodal. Beginning with the two-cell stage, distributions of activity for embryos from In(X)/X females were trimodal, which is evidence for embryonic activity. It is proposed that activation of a maternal mRNA or proenzyme is responsible for the HPRT activity increase in oocytes and early embryos and is supplemented by dosage-dependent activity of the embryonic Hprt gene as early as the two-cell stage. PMID:6618165

  1. Early-light embryonic stimulation suggests a second route, via gene activation, to cerebral lateralization in vertebrates

    PubMed Central

    Chiandetti, Cinzia; Galliussi, Jessica; Andrew, Richard J.; Vallortigara, Giorgio

    2013-01-01

    Genetic factors determine the asymmetrical position of vertebrate embryos allowing asymmetric environmental stimulation to shape cerebral lateralization. In birds, late-light stimulation, just before hatching, on the right optic nerve triggers anatomical and functional cerebral asymmetries. However, some brain asymmetries develop in absence of embryonic light stimulation. Furthermore, early-light action affects lateralization in the transparent zebrafish embryos before their visual system is functional. Here we investigated whether another pathway intervenes in establishing brain specialization. We exposed chicks' embryos to light before their visual system was formed. We observed that such early stimulation modulates cerebral lateralization in a comparable vein of late-light stimulation on active retinal cells. Our results show that, in a higher vertebrate brain, a second route, likely affecting the genetic expression of photosensitive regions, acts before the development of a functional visual system. More than one sensitive period seems thus available to light stimulation to trigger brain lateralization. PMID:24048072

  2. Early-light embryonic stimulation suggests a second route, via gene activation, to cerebral lateralization in vertebrates.

    PubMed

    Chiandetti, Cinzia; Galliussi, Jessica; Andrew, Richard J; Vallortigara, Giorgio

    2013-01-01

    Genetic factors determine the asymmetrical position of vertebrate embryos allowing asymmetric environmental stimulation to shape cerebral lateralization. In birds, late-light stimulation, just before hatching, on the right optic nerve triggers anatomical and functional cerebral asymmetries. However, some brain asymmetries develop in absence of embryonic light stimulation. Furthermore, early-light action affects lateralization in the transparent zebrafish embryos before their visual system is functional. Here we investigated whether another pathway intervenes in establishing brain specialization. We exposed chicks' embryos to light before their visual system was formed. We observed that such early stimulation modulates cerebral lateralization in a comparable vein of late-light stimulation on active retinal cells. Our results show that, in a higher vertebrate brain, a second route, likely affecting the genetic expression of photosensitive regions, acts before the development of a functional visual system. More than one sensitive period seems thus available to light stimulation to trigger brain lateralization.

  3. Effects of petroleum creosote on selected stages of embryonic development

    SciTech Connect

    Iyer, P.R.

    1989-01-01

    The prenatal toxicity of petroleum creosote, a complex mixture of chemicals, was investigated via an in vivo study and an in vitro embryo culture system. Additionally, the prenatal toxicity of naphthalene, one chemical component of petroleum creosote, was determined in the in vitro system. The purpose of the study was to provide specific data on the prenatal toxicity of petroleum creosote and demonstrate the value of the two techniques. In the in vivo study, petroleum creosote was not embryotoxic or teratogenic in ICR mice when administered on gestation days 5-9, at a dose of 4000 mg/kg body weight. In vitro, petroleum creosote becomes embryotoxic to ICR mouse blastocysts at some exposure level between 22 and 33 {mu}g/ml of media. Bioactivation plays a major role in embryotoxicity of naphthalene. Naphthalene without rodent liver microsomal enzymes added to the media was not embryotoxic at levels as high as 100 {mu}g/ml media, whereas naphthalene became embryotoxic at some level between 10 and 50 {mu}g/ml of media in the presence of microsomes. The data indicate that naphthalene is one of the embryotoxic components of petroleum creosote, and that exposure to sufficient levels of petroleum creosote during early pregnancy could result in embryonic loss.

  4. Mapping conduction velocity of early embryonic hearts with a robust fitting algorithm

    PubMed Central

    Gu, Shi; Wang, Yves T; Ma, Pei; Werdich, Andreas A; Rollins, Andrew M; Jenkins, Michael W

    2015-01-01

    Cardiac conduction maturation is an important and integral component of heart development. Optical mapping with voltage-sensitive dyes allows sensitive measurements of electrophysiological signals over the entire heart. However, accurate measurements of conduction velocity during early cardiac development is typically hindered by low signal-to-noise ratio (SNR) measurements of action potentials. Here, we present a novel image processing approach based on least squares optimizations, which enables high-resolution, low-noise conduction velocity mapping of smaller tubular hearts. First, the action potential trace measured at each pixel is fit to a curve consisting of two cumulative normal distribution functions. Then, the activation time at each pixel is determined based on the fit, and the spatial gradient of activation time is determined with a two-dimensional (2D) linear fit over a square-shaped window. The size of the window is adaptively enlarged until the gradients can be determined within a preset precision. Finally, the conduction velocity is calculated based on the activation time gradient, and further corrected for three-dimensional (3D) geometry that can be obtained by optical coherence tomography (OCT). We validated the approach using published activation potential traces based on computer simulations. We further validated the method by adding artificially generated noise to the signal to simulate various SNR conditions using a curved simulated image (digital phantom) that resembles a tubular heart. This method proved to be robust, even at very low SNR conditions (SNR = 2-5). We also established an empirical equation to estimate the maximum conduction velocity that can be accurately measured under different conditions (e.g. sampling rate, SNR, and pixel size). Finally, we demonstrated high-resolution conduction velocity maps of the quail embryonic heart at a looping stage of development. PMID:26114034

  5. Embryonic development of human lice: rearing conditions and susceptibility to spinosad.

    PubMed

    Cueto, Gastón Mougabure; Zerba, Eduardo; Picollo, María Inés

    2006-05-01

    The embryonic development of human lice was evaluated according to the changes in the morphology of the embryo observed through the transparent chorion. Based on ocular and appendage development, three stages of embryogenesis were established: early, medium, and late. Influence of temperature and relative humidity (RH) on the laboratory rearing of Pediculus humanus capitis eggs was assessed. The optimal ranges for temperature and RH were 27-31 degrees C and 45-75%. The susceptibility of head [corrected] louse eggs to insecticide spinosad (a macrocyclic lactone) was assessed by immersion method. The results showed similar susceptibility to spinosad in early, medium, and late stages of head lice eggs. In addition, this study showed similar susceptibility of head and body lice eggs to spinosad, an insecticide that has not been used as pediculicide in Argentina (lethal concentration 50: 0.01%).

  6. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development.

    PubMed

    Abu-Issa, Radwan

    2015-01-24

    Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell-cell and/or cellmatrix adhesion during cardiac development.

  7. Comparative proteome analysis of Milnesium tardigradum in early embryonic state versus adults in active and anhydrobiotic state

    PubMed Central

    Schokraie, Elham; Warnken, Uwe; Hotz-Wagenblatt, Agnes; Grohme, Markus A.; Hengherr, Steffen; Förster, Frank; Schill, Ralph O.; Frohme, Marcus; Dandekar, Thomas; Schnölzer, Martina

    2012-01-01

    Tardigrades have fascinated researchers for more than 300 years because of their extraordinary capability to undergo cryptobiosis and survive extreme environmental conditions. However, the survival mechanisms of tardigrades are still poorly understood mainly due to the absence of detailed knowledge about the proteome and genome of these organisms. Our study was intended to provide a basis for the functional characterization of expressed proteins in different states of tardigrades. High-throughput, high-accuracy proteomics in combination with a newly developed tardigrade specific protein database resulted in the identification of more than 3000 proteins in three different states: early embryonic state and adult animals in active and anhydrobiotic state. This comprehensive proteome resource includes protein families such as chaperones, antioxidants, ribosomal proteins, cytoskeletal proteins, transporters, protein channels, nutrient reservoirs, and developmental proteins. A comparative analysis of protein families in the different states was performed by calculating the exponentially modified protein abundance index which classifies proteins in major and minor components. This is the first step to analyzing the proteins involved in early embryonic development, and furthermore proteins which might play an important role in the transition into the anhydrobiotic state. PMID:23029181

  8. Comparative proteome analysis of Milnesium tardigradum in early embryonic state versus adults in active and anhydrobiotic state.

    PubMed

    Schokraie, Elham; Warnken, Uwe; Hotz-Wagenblatt, Agnes; Grohme, Markus A; Hengherr, Steffen; Förster, Frank; Schill, Ralph O; Frohme, Marcus; Dandekar, Thomas; Schnölzer, Martina

    2012-01-01

    Tardigrades have fascinated researchers for more than 300 years because of their extraordinary capability to undergo cryptobiosis and survive extreme environmental conditions. However, the survival mechanisms of tardigrades are still poorly understood mainly due to the absence of detailed knowledge about the proteome and genome of these organisms. Our study was intended to provide a basis for the functional characterization of expressed proteins in different states of tardigrades. High-throughput, high-accuracy proteomics in combination with a newly developed tardigrade specific protein database resulted in the identification of more than 3000 proteins in three different states: early embryonic state and adult animals in active and anhydrobiotic state. This comprehensive proteome resource includes protein families such as chaperones, antioxidants, ribosomal proteins, cytoskeletal proteins, transporters, protein channels, nutrient reservoirs, and developmental proteins. A comparative analysis of protein families in the different states was performed by calculating the exponentially modified protein abundance index which classifies proteins in major and minor components. This is the first step to analyzing the proteins involved in early embryonic development, and furthermore proteins which might play an important role in the transition into the anhydrobiotic state.

  9. Sire effect on early and late embryonic death in French Holstein cattle.

    PubMed

    Ledoux, D; Ponsart, C; Grimard, B; Gatien, J; Deloche, M C; Fritz, S; Lefebvre, R; Humblot, P

    2015-05-01

    We investigated the effect of maternal sire on early pregnancy failure (between D0, day of insemination and D90) in their progeny during the first and second lactations (n=3508) in the Holstein breed. The estimated breeding value (EBV) for cow fertility of 12 bulls (reliability⩾0.95) was used to create the following three groups: low, medium and high EBV (EBV from -0.7 to 1 expressed as genetic standard deviation relative to the mean of the breed). In their daughters (93 to 516 per bull), progesterone measurement was carried out on the day of artificial insemination (AI; D0) to check whether the cows were in the follicular phase and on D18 to 25 to assess non-fertilisation-early embryonic mortality (NF-EEM). Late embryonic mortality (LEM) and early foetal death (FD) were determined by ultrasonography on D45 and D90 and by the return to oestrus after the first AI. Frequencies of NF-EEM, LEM, FD and pregnancy were 33.3%, 11.7%, 1.4% and 48.5% and incidences were 35.1, 19.0, 2.7 and 51.1, respectively. Sire EBV was significantly related to the incidences of pregnancy failure between D0 and D90, fertilisation failure-early embryonic mortality (FF-EEM) and LEM but not to the incidence of FD between D45 and D90 of pregnancy. The relative risk (RR) of FF-EEM was significantly higher (RR=1.2; P<0.05) for the progeny group of low EBV bulls when compared with high EBV bulls. The same effect was observed when comparing LEM of the progeny groups from the low EBV bulls to those from moderate and high EBV bulls (RR, respectively, of 1.3 and 1.4; P<005). The incidence of FF-EEM was significantly higher when cows were inseminated before 80 days postpartum compared with later, and for the extreme values of the difference between milk fat and protein content measured during the first 3 months of lactation. FF-EEM was also significantly related to the year of observation. The incidence of LEM was higher for the highest producing cows and was influenced by interaction between milk

  10. Thalidomide induced early gene expression perturbations indicative of human embryopathy in mouse embryonic stem cells

    SciTech Connect

    Gao, Xiugong Sprando, Robert L.; Yourick, Jeffrey J.

    2015-08-15

    Developmental toxicity testing has traditionally relied on animal models which are costly, time consuming, and require the sacrifice of large numbers of animals. In addition, there are significant disparities between human beings and animals in their responses to chemicals. Thalidomide is a species-specific developmental toxicant that causes severe limb malformations in humans but not in mice. Here, we used microarrays to study transcriptomic changes induced by thalidomide in an in vitro model based on differentiation of mouse embryonic stem cells (mESCs). C57BL/6 mESCs were allowed to differentiate spontaneously and RNA was collected at 24, 48, and 72 h after exposure to 0.25 mM thalidomide. Global gene expression analysis using microarrays revealed hundreds of differentially expressed genes upon thalidomide exposure that were enriched in gene ontology (GO) terms and canonical pathways associated with embryonic development and differentiation. In addition, many genes were found to be involved in small GTPases-mediated signal transduction, heart development, and inflammatory responses, which coincide with clinical evidences and may represent critical embryotoxicities of thalidomide. These results demonstrate that transcriptomics in combination with mouse embryonic stem cell differentiation is a promising alternative model for developmental toxicity assessment. - Highlights: • Studied genomic changes in mouse embryonic stem cells upon thalidomide exposure • Identified gene expression changes that may represent thalidomide embryotoxicity • The toxicogenomic changes coincide well with known thalidomide clinical outcomes. • The mouse embryonic stem cell model is suitable for developmental toxicity testing. • The model has the potential for high-throughput screening of a multitude of compounds.

  11. Early Developments, 1998.

    ERIC Educational Resources Information Center

    Little, Loyd, Ed.

    1998-01-01

    This document consists of the two 1998 issues of a journal reporting new research in early child development conducted by the Frank Porter Graham Child Development Center at the University of North Carolina at Chapel Hill. In the Spring 1998 issue, articles highlight the Center's diverse cross-cultural projects and global research, training and…

  12. Early Developments, 2002.

    ERIC Educational Resources Information Center

    Winton, Pam, Ed.; Buysse, Virginia, Ed.

    2002-01-01

    This document consists of the three 2002 issues of a journal reporting new research in early child development conducted by the Frank Porter Graham Child Development Center (FPG) at the University of North Carolina at Chapel Hill. Articles in the Winter 2002 issue highlight some current work at FPG on factors that enhance or inhibit social and…

  13. Early Developments, 2000.

    ERIC Educational Resources Information Center

    Little, Loyd, Ed.

    2000-01-01

    This document consists of the three 2000 issues of a journal reporting new research in early child development conducted by the Frank Porter Graham Child Development Center at the University of North Carolina at Chapel Hill. Articles in the spring 2000 issue focus on a follow-up study of the Abecedarian Project, children of depressed mothers,…

  14. Early development and embryology of the platypus.

    PubMed Central

    Hughes, R L; Hall, L S

    1998-01-01

    Information on the pre-hatching development of the platypus, Ornithorhynchus anatinus, is reliant on a small number of specimens, whose precise age is unknown. Material collected for J. P. Hill and now housed in the Hubrecht International Embryological Laboratory, Utrecht, contributes a major source of specimens. This paper presents new observations on developmental stages from the Hill collection, which allow for a more complete description of pre-hatching development. A feature of the pre-embryonic development of the platypus is the incomplete meroblastic cleavage. A column of fine yolk spheres extends from beneath the embryonic blastodisc towards the centre of a yolky vitellus, as seen in birds. The major expansion of extra-embryonic membranes occurs after the formation of the primitive streak. The primitive streak develops within an embryonal area as part of the superficial wall of the yolk-sac, a feature also shared with marsupials, birds and reptiles. The full-term, subspheroidal, intrauterine egg of the platypus has a major axis of about 17 mm and contains a flat, 19-20 somite, neurula-stage embryo which has prominent trigeminal ganglion primordia. The embryo at this stage is in a period of rapid modelling of the major early organ primordia of the nervous system, cardiovascular system, excretory system, and somite-derived components of the body wall. Soon after laying, five primary brain vesicles are present, the trigeminal ganglia CN5 as well as CN7, CN8, CN9, CN10, CN11 and CN12 are well developed. The alimentary system has an expanded stomach, pancreatic primordia and a gall bladder. Mesonephric tubules are associated with patent mesonephric ducts, which empty laterally into the cloaca. Extra-embryonic membranes at this stage show an extensive chorioamniotic connection that extends through the greater part of the caudal half of fused amniotic folds. The vascularized yolk-sac consists of a superficial yolk-sac omphalopleura and a deep yolk

  15. The role of the pupal determinant broad during embryonic development of a direct-developing insect

    PubMed Central

    Rynerson, Melody R.; Truman, James W.; Riddiford, Lynn M.

    2010-01-01

    Metamorphosis is one of the most common, yet dramatic of life history strategies. In insects, complete metamorphosis with morphologically distinct larval stages arose from hemimetabolous ancestors that were more direct developing. Over the past century, several ideas have emerged that suggest the holometabolous pupa is developmentally homologous to the embryonic stages of the hemimetabolous ancestor. Other theories consider the pupal stage to be a modification of a hemimetabolous nymph. To address this question, we have isolated an ortholog of the pupal determinant, broad (br), from the hemimetabolous milkweed bug and examined its role during embryonic development. We show that Oncopeltus fasciatus br (Of'br) is expressed in two phases. The first occurs during germ band invagination and segmentation when Of'br is expressed ubiquitously in the embryonic tissues. The second phase of Of'br expression appears during the pronymphal phase of embryogenesis and persists through nymphal differentiation to decline just before hatching. Knock-down of Of'br transcripts results in defects that range from posterior truncations in the least-affected phenotypes to completely fragmented embryonic tissues in the most severe cases. Analysis of the patterning genes engrailed and hunchback reveal loss of segments and a failure in neural differentiation after Of'br depletion. Finally, we show that br is constitutively expressed during embyrogenesis of the ametabolous firebrat, Thermobia domestica. This suggests that br expression is prominent during embryonic development of ametabolous and hemimetabolous insects but was lost with the emergence of the completely metamorphosing insects. PMID:20127251

  16. Regulators of thyroid hormone availability and action in embryonic chicken brain development.

    PubMed

    Van Herck, Stijn L J; Geysens, Stijn; Delbaere, Joke; Darras, Veerle M

    2013-09-01

    Thyroid hormones (THs) are crucial elements in vertebrate brain development. They exert their action mainly through binding of 3,5,3'-triiodothyronine (T3) to nuclear receptors that directly influence the expression of TH-regulated genes. Intracellular TH action is therefore dependent on both the availability of T3 and its receptors. TH uptake in cells is regulated by specific TH transporters and local activation and inactivation is regulated by deiodinases. This review provides an overview of the general expression pattern of TH transporters, deiodinases and receptors during embryonic chicken brain development and compares it to the situation in mammals. It is clear that THs and their regulators are present in the embryonic brain from the early stages of development, long before the onset of embryonic thyroid gland functioning. The mechanism of TH uptake across the brain barriers during development is only partly understood. At the developing blood-brain-barrier expression of the TH-activating type 2 deiodinase is closely associated with the blood vessels, but contrary to the situation in (adult) mammals no expression of MCT8 or OATP1C1 TH transporters is found at that level in the developing chicken. At the blood-cerebrospinal fluid-barrier co-expression of the TH-inactivating type 3 deiodinase and MCT8 and OATP1C1 is found in birds and mammals. These comparative data show overlapping patterns, pointing to general mechanisms, but also indicate specific interspecies differences that may help to understand species-specific responses to regulator gene knockout/mutation. Copyright © 2013 Elsevier Inc. All rights reserved.

  17. Part II: morphological analysis of embryonic development following femtosecond laser manipulation

    NASA Astrophysics Data System (ADS)

    Kohli, V.; Elezzabi, A. Y.

    2008-02-01

    The zebrafish (Danio rerio) is an attractive model system that has received wide attention for its usefulness in the study of development and disease. This organism represents a closer analog to humans than the common invetebrates Drosophila melanogaster and Caenorhabditis elegans, making this species an ideal model for human health research. Non-invasive manipulation of the zebrafish has been challenging, owing to the outer proteinaceous membrane and multiple embryonic barriers. A novel tool capable of manipulating early cleavage stage embryonic cells would be important for future advancements in medial research and the aquaculture industry. Herein, we demonstrate the laser surgery of early cleavage stage (2-cell) blastomere cells using a range of average laser powers and beam dwell times. Since the novelty of this manipulation tool depends on its non-invasive application, we examined short- and long-term laser-induced developmental defects following embryonic surgery. Laser-manipulated embryos were reared to 2 and 7 days post-fertilization and compared to control embryos at the same developmental stages. Morphological analysis was performed using light microscopy and scanning electron microscopy. Developmental features that were examined included the antero- and dorsal-lateral whole body views of the larvae, the olfactory pit, dorsal, ventral and pectoral fins, notochord, pectoral fin buds, otic capsule, otic vesicle, neuromast patterning, and kinocilia of the olfactory pit rim and cristae of the lateral wall of the ear. Laser-manipulated embryos developed normally relative to the controls, with developmental patterning and morphology at 2 and 7 days indistinguishable from control larvae.

  18. Mechanobiology of Embryonic Skeletal Development: Insights from Animal Models

    PubMed Central

    Nowlan, Niamh C.; Sharpe, James; Roddy, Karen A.; Prendergast, Patrick J.; Murphy, Paula

    2016-01-01

    A range of clinical conditions in which foetal movement is reduced or prevented can have a severe effect on skeletal development. Animal models have been instrumental to our understanding of the interplay between mechanical forces and skeletal development, in particular the mouse and the chick model systems. In the chick, the most commonly used means of altering the mechanical environment is by pharmaceutical agents which induce paralysis, while genetically modified mice with non-functional or absent skeletal muscle offer a valuable tool for examining the interplay between muscle forces and skeletogenesis in mammals. This article reviews the body of research on animal models of bone or joint formation in vivo in the presence of an altered or abnormal mechanical environment. In both immobilised chicks and ‘muscleless limb’ mice, a range of effects are seen, such as shorter rudiments with less bone formation, changes in rudiment and joint shape and abnormal joint cavitation. However, while all bones and synovial joints are affected in immobilised chicks, some rudiments and joints are unaffected in muscleless mice. We propose that extrinsic mechanical forces from movements of the mother or littermates impact on skeletogenesis in mammals, while the chick embryo is reliant on intrinsic movement for mechanical stimulation. The insights gained from animal models into the mechanobiology of embryonic skeletal development could provide valuable cues to prospective tissue engineers of cartilage and bone, and contribute to new or improved treatments to minimise the impact on skeletal development of human disorders of reduced movement in utero. PMID:20860060

  19. Autonomy of tendon development in the embryonic chick wing.

    PubMed

    Kieny, M; Chevallier, A

    1979-01-01

    The aim of this study performed in the embryonic chick wing is to test the ability of the tendons to form and develop in the absence of the muscle bellies. The experiments were performed on 2-day chick embryos by destroying a portion of the somitic mesoderm by local X-irradiation. The irradiated part included the wing somite level 15-20 and extended three somites (or presumptive somites) in front and two to six presumptive somites in the rear of the wing somite levels. The wings of the operated side were examined histologically 3-8 days after the X-irradiation. The radio-destruction of the somitic mesoderm totally inhibited or severely impaired the development of the forearm muscles. But, despite the absence of the flexor and extensor muscles the differentiation of the distal manus tendons could be observed. This differentiation occurred at the same time and in the same positions as in controls. However, these tendons were transient structures. They disappeared within three days after their individuation. Two mechanisms that progressed in proximo-distal direction were involved in their resorption: cellular dislocation and cell death. We conclude that tendons start to develop autonomously from the muscle bulks, but for their maintenance and further development they require connexion to a muscle belly.

  20. Embryonic growth discordance and early fetal loss: the STORK multiple pregnancy cohort and systematic review.

    PubMed

    D'Antonio, F; Khalil, A; Mantovani, E; Thilaganathan, B

    2013-10-01

    Is there an association between discordance in embryonic growth and fetal loss at the time of the 11-14-week scan in twin pregnancies? Regardless of the chorionicity, crown rump length (CRL) discordance at 7(+0)-9(+6) weeks is predictive of subsequent single fetal demise in the first trimester. Previous small studies have reported a variable association between discordance in embryonic growth and subsequent fetal loss. Retrospective study of all twin pregnancies of known chorionicity from a large regional cohort over a 10-year period. A total of 1356 twin pregnancies (288 monochorionic and 1068 dichorionic) were included in the study. Women presenting to the early pregnancy unit were included in the study. Logistic regression, ROC curve and Kaplan-Meier analyses were performed to evaluate the association between CRL discordance at 7(+0)-9(+6) weeks and spontaneous single fetal loss diagnosed at the 11-14-week scan. A systematic review was also performed using MEDLINE, EMBASE, Cinahl and the Cochrane Library in order to explore the relationship between early growth discordance and single fetal loss in twin pregnancies. There were 111 (8.2%) single fetal losses diagnosed at 11-14 weeks in this cohort. At multivariate analysis, CRL discordance percentile [odds ratio (OR) 1.20; 95% confidence interval (CI), 1.12-1.63, P < 0.0001] and CRL <5th centile of at least one twin (OR, 2.21; 95% CI 1.23-4.24, P = 0.023), but not chorionicity (P = 0.486) or maternal age (P = 0.283) was independently associated with the loss of one fetus at the 11-14-week scan. The predictive accuracy of CRL discordance for single fetal loss was high (AUC = 0.93; 95% CI = 0.91-0.94). A significant association was found between the increase in the degree of embryonic discordance and the likelihood of early fetal loss (P < 0.0001). Only a high-risk population was analysed. Therefore, the patients studied were not a representative sample from the population of women pregnant with twins. Twin

  1. Live imaging of mitosis in the developing mouse embryonic cortex.

    PubMed

    Pilaz, Louis-Jan; Silver, Debra L

    2014-06-04

    Although of short duration, mitosis is a complex and dynamic multi-step process fundamental for development of organs including the brain. In the developing cerebral cortex, abnormal mitosis of neural progenitors can cause defects in brain size and function. Hence, there is a critical need for tools to understand the mechanisms of neural progenitor mitosis. Cortical development in rodents is an outstanding model for studying this process. Neural progenitor mitosis is commonly examined in fixed brain sections. This protocol will describe in detail an approach for live imaging of mitosis in ex vivo embryonic brain slices. We will describe the critical steps for this procedure, which include: brain extraction, brain embedding, vibratome sectioning of brain slices, staining and culturing of slices, and time-lapse imaging. We will then demonstrate and describe in detail how to perform post-acquisition analysis of mitosis. We include representative results from this assay using the vital dye Syto11, transgenic mice (histone H2B-EGFP and centrin-EGFP), and in utero electroporation (mCherry-α-tubulin). We will discuss how this procedure can be best optimized and how it can be modified for study of genetic regulation of mitosis. Live imaging of mitosis in brain slices is a flexible approach to assess the impact of age, anatomy, and genetic perturbation in a controlled environment, and to generate a large amount of data with high temporal and spatial resolution. Hence this protocol will complement existing tools for analysis of neural progenitor mitosis.

  2. Frizzled 3 acts upstream of Alcam during embryonic eye development.

    PubMed

    Seigfried, Franziska A; Cizelsky, Wiebke; Pfister, Astrid S; Dietmann, Petra; Walther, Paul; Kühl, Michael; Kühl, Susanne J

    2017-06-01

    Formation of a functional eye during vertebrate embryogenesis requires different processes such as cell differentiation, cell migration, cell-cell interactions as well as intracellular signalling processes. It was previously shown that the non-canonical Wnt receptor Frizzled 3 (Fzd3) is required for proper eye formation, however, the underlying mechanism is poorly understood. Here we demonstrate that loss of Fzd3 induces severe malformations of the developing eye and that this defect is phenocopied by loss of the activated leukocyte cell adhesion molecule (Alcam). Promoter analysis revealed the presence of a Fzd3 responsive element within the alcam promoter, which is responsible for alcam expression during anterior neural development. In-depth analysis identified the jun N-terminal protein kinase 1 (JNK1) and the transcription factor paired box 2 (Pax2) to be important for the activation of alcam expression. Altogether our study reveals that alcam is activated through non-canonical Wnt signalling during embryonic eye development in Xenopus laevis and shows that this pathway plays a similar role in different tissues. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Identification and Expression Analysis of Zebrafish Glypicans during Embryonic Development

    PubMed Central

    Gupta, Mansi; Brand, Michael

    2013-01-01

    Heparan sulfate Proteoglycans (HSPG) are ubiquitous molecules with indispensable functions in various biological processes. Glypicans are a family of HSPG’s, characterized by a Gpi-anchor which directs them to the cell surface and/or extracellular matrix where they regulate growth factor signaling during development and disease. We report the identification and expression pattern of glypican genes from zebrafish. The zebrafish genome contains 10 glypican homologs, as opposed to six in mammals, which are highly conserved and are phylogenetically related to the mammalian genes. Some of the fish glypicans like Gpc1a, Gpc3, Gpc4, Gpc6a and Gpc6b show conserved synteny with their mammalian cognate genes. Many glypicans are expressed during the gastrulation stage, but their expression becomes more tissue specific and defined during somitogenesis stages, particularly in the developing central nervous system. Existence of multiple glypican orthologs in fish with diverse expression pattern suggests highly specialized and/or redundant function of these genes during embryonic development. PMID:24244720

  4. Identification and expression analysis of zebrafish glypicans during embryonic development.

    PubMed

    Gupta, Mansi; Brand, Michael

    2013-01-01

    Heparan sulfate Proteoglycans (HSPG) are ubiquitous molecules with indispensable functions in various biological processes. Glypicans are a family of HSPG's, characterized by a Gpi-anchor which directs them to the cell surface and/or extracellular matrix where they regulate growth factor signaling during development and disease. We report the identification and expression pattern of glypican genes from zebrafish. The zebrafish genome contains 10 glypican homologs, as opposed to six in mammals, which are highly conserved and are phylogenetically related to the mammalian genes. Some of the fish glypicans like Gpc1a, Gpc3, Gpc4, Gpc6a and Gpc6b show conserved synteny with their mammalian cognate genes. Many glypicans are expressed during the gastrulation stage, but their expression becomes more tissue specific and defined during somitogenesis stages, particularly in the developing central nervous system. Existence of multiple glypican orthologs in fish with diverse expression pattern suggests highly specialized and/or redundant function of these genes during embryonic development.

  5. High-Sensitivity Mass Spectrometry for Probing Gene Translation in Single Embryonic Cells in the Early Frog (Xenopus) Embryo

    PubMed Central

    Lombard-Banek, Camille; Moody, Sally A.; Nemes, Peter

    2016-01-01

    Direct measurement of protein expression with single-cell resolution promises to deepen the understanding of the basic molecular processes during normal and impaired development. High-resolution mass spectrometry provides detailed coverage of the proteomic composition of large numbers of cells. Here we discuss recent mass spectrometry developments based on single-cell capillary electrophoresis that extend discovery proteomics to sufficient sensitivity to enable the measurement of proteins in single cells. The single-cell mass spectrometry system is used to detect a large number of proteins in single embryonic cells in the 16-cell embryo of the South African clawed frog (Xenopus laevis) that give rise to distinct tissue types. Single-cell measurements of protein expression provide complementary information on gene transcription during early development of the vertebrate embryo, raising a potential to understand how differential gene expression coordinates normal cell heterogeneity during development. PMID:27761436

  6. Gold nanorods induce early embryonic developmental delay and lethality in zebrafish (Danio rerio).

    PubMed

    Mesquita, Bárbara; Lopes, Isabel; Silva, Susana; Bessa, Maria João; Starykevich, Maksim; Carneiro, Jorge; Galvão, Tiago L P; Ferreira, Mário G S; Tedim, João; Teixeira, João Paulo; Fraga, Sónia

    2017-07-11

    Due to their unique electronic and optical features, gold nanoparticles (AuNP) have received a great deal of attention for application in different fields such as catalysis, electronics, and biomedicine. The large-volume manufacturing predicted for future decades and the inevitable release of these substances into the environment necessitated an assessment of potential adverse human and ecological risks due to exposure to AuNP. Accordingly, this study aimed to examine the acute and developmental toxicity attributed to a commercial suspension of Au nanorods stabilized with cetyltrimethylammonium bromide (CTAB-AuNR) using early embryonic stages of zebrafish (Danio rerio), a well-established model in ecotoxicology. Zebrafish embryos were exposed to CTAB-AuNR (0-150 µg/L) to determine for developmental assessment until 96 hr post fertilization (hpf) and lethality. Uptake of CTAB-AuNR by embryos and nanoparticles potential to induce DNA damage was also measured at 48 and 96 hpf. Analysis of the concentration-response curves with cumulative mortality at 96 hpf revealed a median lethal concentration (LC50,96h) of 110.2 μg/L. At sublethal concentrations, CTAB-AuNR suspensions were found to produce developmental abnormalities such as tail deformities, pericardial edema, decreased body length, and delayed eye, head, and tail elongation development. Further, less than 1% of the initial concentration of CTAB-AuNR present in the exposure media was internalized by zebrafish embryos prior to (48 hpf) and after hatching (96 hpf). In addition, no marked DNA damage was detected in embryos after exposure to CTAB-AuNR. Overall, CTAB-AuNR suspensions produced lethal and sublethal effects on zebrafish embryos with possible repercussions in fitness of adult stages. However, these results foresee a low risk for fish since the observed effects occurred at concentrations above the levels expected to find in the aquatic environment.

  7. Two human homeobox genes, c1 and c8: structure analysis and expression in embryonic development

    SciTech Connect

    Simeone, A.; Mavilio, F.; Acampora, D.; Giampaolo, A.; Faiella, A.; Zappavigna, V.; D'Esposito, M.; Pannese, M.; Russo, G.; Boncinelli, E.; Peschle, C.

    1987-07-01

    Two human cDNA clones (HHO.c1.95 and HHO.c8.5111) containing a homeobox region have been characterized, and the respective genomic regions have been partially analyzed. Expression of the corresponding genes, termed c1 and c8, was evaluated in different organs and body parts during human embryonic/fetal development. HHO.c1.95 apparently encodes a 217-amino acid protein containing a class I homeodomain that shares 60 out of 61 amino acid residues with the Antennapedia homeodomain of Drosophila melanogaster. HHO.c8.5111 encodes a 153-amino acid protein containing a homeodomains identical to that of the frog AC1 gene. Clones HHO.c1 and HHO.c8 detect by blot-hybridization one and two specific polyadenylylated transcripts, respectively. These are differentially expressed in spinal cord, backbone rudiments, limb buds (or limbs), heart, and skin of human embryos and early fetuses in the 5- to 9-week postfertilization period, thus suggesting that the c1 and c8 genes play a key role in a variety of developmental processes. Together, the results of the embryonic/fetal expression of c1 and c8 and those of two previously analyzed genes (c10 and c13) indicate a coherent pattern of expression of these genes in early human ontogeny.

  8. Sperm morphology and preparation method affect bovine embryonic development.

    PubMed

    Walters, Anneke H; Eyestone, Willard E; Saacke, Richard G; Pearson, Ronald E; Gwazdauskas, Francis C

    2004-01-01

    This study was conducted to evaluate the effect of sperm separation methods of semen samples collected from bulls subjected to scrotal insulation on embryonic development after in vitro fertilization (IVF) and to determine whether IVF results would be affected by various heparin concentrations. Morphologically abnormal semen samples were obtained and cryopreserved from Holstein bulls following scrotal insulation for 48 hours. Standard protocols using the Percoll gradient (90%/45%) method and the swim-up method were used to separate spermatozoa fractions in experiment I. The pellet (A(p)) and the 45% layer (B(p)) were isolated from the Percoll separation, while for the swim-up separation, the supernatant (A(s)) and the interphase (B(s)) were isolated. The overall blastocyst rate for our laboratory control semen was 23.1 +/- 2.1% for Percoll separations (A(p) and B(p)) and 18.2 +/- 2.0% for swim-up (A(s) and B(s)) separations. This rate was higher (P <.01) than the rate observed for the semen from the bull that had the greatest response to scrotal insult 5 days prior to the insult, when it was 9.2 +/- 2.1% for the Percoll separation and 20.7 +/- 2.3% for the swim-up separation, while semen from 27 days after scrotal insulation (D +27) resulted in no blastocyst formation for the Percoll separation and a 4.2 +/- 2.1% rate for the swim-up separation. In experiment II, semen was sampled from the bulls that responded in the greatest and least degrees to scrotal insult 5 days before scrotal insulation (D -5) and on days 23 (D +23) and 34 (D +34) after scrotal insulation. These samples were exposed to IVF mediums with 3 different heparin concentrations (0.1, 1.0, and 10 microg/mL). There was a significant difference (P <.05) in developmental scores between the D -5 (1.08 +/- 0.08), D +23 (0.9 +/- 0.08), and D +34 (0.8 +/- 0.08) samples, but no differences were observed in blastocyst formation based on the number of cleaved embryos. Increasing the heparin concentration

  9. Early Program Development

    NASA Image and Video Library

    1971-01-01

    This 1971 artist's concept shows a Nuclear Shuttle and an early Space Shuttle docked with an Orbital Propellant Depot. As envisioned by Marshall Space Flight Center Program Development persornel, an orbital modular propellant storage depot, supplied periodically by the Space Shuttle or Earth-to-orbit fuel tankers, would be critical in making available large amounts of fuel to various orbital vehicles and spacecraft.

  10. Early Program Development

    NASA Image and Video Library

    1970-01-01

    This artist's concept from 1970 shows a Nuclear Shuttle docked to an Orbital Propellant Depot and an early Space Shuttle. As envisioned by Marshall Space Flight Center Program Development plarners, the Nuclear Shuttle, in either manned or unmanned mode, would deliver payloads to lunar orbit or other destinations then return to Earth orbit for refueling and additonal missions.

  11. Diverging functions of Scr between embryonic and post-embryonic development in a hemimetabolous insect, Oncopeltus fasciatus

    PubMed Central

    Chesebro, John; Hrycaj, Steven; Mahfooz, Najmus; Popadić, Aleksandar

    2009-01-01

    Hemimetabolous insects undergo an ancestral mode of development in which embryos hatch into first nymphs that resemble miniature adults. While recent studies have shown that homeotic (hox) genes establish segmental identity of first nymphs during embryogenesis, no information exists on the function of these genes during post-embryogenesis. To determine whether and to what degree hox genes influence the formation of adult morphologies, we performed a functional analysis of Sex combs reduced (Scr) during post-embryonic development in Oncopeltus fasciatus. The main effect was observed in prothorax of Scr-RNAi adults, and ranged from significant alterations in its size and shape to a near complete transformation of its posterior half toward a T2-like identity. Furthermore, while the consecutive application of Scr-RNAi at both of the final two post-embryonic stages (fourth and fifth) did result in formation of ectopic wings on T1, the individual applications at each of these stages did not. These experiments provide two new insights into evolution of wings. First, the role of Scr in wing repression appears to be conserved in both holo- and hemimetabolous insects. Second, the prolonged Scr-depletion (spanning at least two nymphal stages) is both necessary and sufficient to restart wing program. At the same time, other structures that were previously established during embryogenesis are either unaffected (T1 legs) or display only minor changes (labium) in adults. These observations reveal a temporal and spatial divergence of Scr roles during embryonic (main effect in labium) and post-embryonic (main effect in prothorax) development. PMID:19382295

  12. Optical mapping of conduction in early embryonic quail hearts with light-sheet microscopy (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Ma, Pei; Gu, Shi; Wang, Yves T.; Jenkins, Michael W.; Rollins, Andrew M.

    2016-03-01

    Optical mapping (OM) using fluorescent voltage-sensitive dyes (VSD) to measure membrane potential is currently the most effective method for electrophysiology studies in early embryonic hearts due to its noninvasiveness and large field-of-view. Conventional OM acquires bright-field images, collecting signals that are integrated in depth and projected onto a 2D plane, not capturing the 3D structure of the sample. Early embryonic hearts, especially at looping stages, have a complicated, tubular geometry. Therefore, conventional OM cannot provide a full picture of the electrical conduction circumferentially around the heart, and may result in incomplete and inaccurate measurements. Here, we demonstrate OM of Hamburger and Hamilton stage 14 embryonic quail hearts using a new commercially-available VSD, Fluovolt, and depth sectioning using a custom built light-sheet microscopy system. Axial and lateral resolution of the system is 14µm and 8µm respectively. For OM imaging, the field-of-view was set to 900µm×900µm to cover the entire heart. 2D over time OM image sets at multiple cross-sections through the looping-stage heart were recorded. The shapes of both atrial and ventricular action potentials acquired were consistent with previous reports using conventional VSD (di-4-ANNEPS). With Fluovolt, signal-to-noise ratio (SNR) is improved significantly by a factor of 2-10 (compared with di-4-ANNEPS) enabling light-sheet OM, which intrinsically has lower SNR due to smaller sampling volumes. Electrophysiologic parameters are rate dependent. Optical pacing was successfully integrated into the system to ensure heart rate consistency. This will also enable accurately gated reconstruction of full four dimensional conduction maps and 3D conduction velocity measurements.

  13. Rac1 modulates cardiomyocyte adhesion during mouse embryonic development

    SciTech Connect

    Abu-Issa, Radwan

    2015-01-24

    Highlights: • Conditional knockout of Rac1 using Nkx2.5 Cre line is lethal at E13.5. • The myocardium of the mutant is thin and disorganized. • The phenotype is not due to cardiomyocyte low proliferation or apoptosis. • The phenotype is due to specific defect in cardiomyocyte adhesion. - Abstract: Rac1, a member of the Rho subfamily of small GTPases, is involved in morphogenesis and differentiation of many cell types. Here we define a role of Rac1 in cardiac development by specifically deleting Rac1 in the pre-cardiac mesoderm using the Nkx2.5-Cre transgenic driver line. Rac1-conditional knockout embryos initiate heart development normally until embryonic day 11.5 (E11.5); their cardiac mesoderm is specified, and the heart tube is formed and looped. However, by E12.5-E13.5 the mutant hearts start failing and embryos develop edema and hemorrhage which is probably the cause for the lethality observed soon after. The hearts of Rac1-cKO embryos exhibit disorganized and thin myocardial walls and defects in outflow tract alignment. No significant differences of cardiomyocyte death or proliferation were found between developing control and mutant embryos. To uncover the role of Rac1 in the heart, E11.5 primary heart cells were cultured and analyzed in vitro. Rac1-deficient cardiomyocytes were less spread, round and loosely attached to the substrate and to each other implying that Rac1-mediated signaling is required for appropriate cell–cell and/or cellmatrix adhesion during cardiac development.

  14. Development of an invitro technique to use mouse embryonic stem cell in evaluating effects of xenobiotics

    EPA Science Inventory

    Our goal has been to develop a high-throughput, in vitro technique for evaluating the effects of xenobiotics using mouse embryonic stem cells (mESCs). We began with the Embryonic Stem Cell Test (EST), which is used to predict the embryotoxic potential of a test compound by combin...

  15. Development of an invitro technique to use mouse embryonic stem cell in evaluating effects of xenobiotics

    EPA Science Inventory

    Our goal has been to develop a high-throughput, in vitro technique for evaluating the effects of xenobiotics using mouse embryonic stem cells (mESCs). We began with the Embryonic Stem Cell Test (EST), which is used to predict the embryotoxic potential of a test compound by combin...

  16. Embryonic development rates of northern grasshoppers (Orthoptera: Acrididae): implications for climate change and habitat management

    USDA-ARS?s Scientific Manuscript database

    Temperature-dependent rates of embryonic development are a primary determinant of the life cycle of many species of grasshoppers which, in cold climates, spend two winters in the egg stage. Knowledge of embryonic developmental rates is important for an assessment of the effects of climate change and...

  17. Early embryonic failure: Expression and imprinted status of candidate genes on human chromosome 21

    SciTech Connect

    Sherman, L.S.; Bennett, P.R.; Moore, G.E.

    1994-09-01

    Two cases of maternal uniparental (hetero)disomy for human chromosome 21 (mUPD21) have been identified in a systematic search for UPD in 23 cases of early embryonic failure (EEF). Bi-parental origin of the other chromosome pairs was confirmed using specific VNTR probes or dinucleotide repeat analysis. Both maternally and paternally derived isochromosomes 21q have previously been identified in two individuals with normal phenotypes. Full UPD21 has a different mechanism of origin than uniparental isochromosome 21q and its effect on imprinted genes and phenotypic outcome will therefore not necessarily be the same. EEF associated with mUPD21 suggests that developmentally important genes on HSA 21 may be imprinted such that they are only expressed from either the maternally or paternally derived alleles. We have searched for monoallelic expression of candidate genes on HSA 21 in human pregnancy (CBS, IFNAR, COL6A1) using intragenic DNA polymorphisms. These genes were chosen either because their murine homologues lie in imprinted regions or because they are potentially important in embryogenesis. Once imprinted candidate genes have been identified, their methylation status and expression in normal, early embryonic failure and uniparental disomy 21 pregnancies will be studied. At the same time, a larger number of cases of EEF are being examined to further investigate the incidence of UPD21 in this group.

  18. Embryonic development of the sea bass Dicentrarchus labrax

    NASA Astrophysics Data System (ADS)

    Cucchi, Patricia; Sucré, Elliott; Santos, Raphaël; Leclère, Jeremy; Charmantier, Guy; Castille, René

    2012-06-01

    The embryonic development of the sea bass Dicentrarchus labrax during the endotrophic period is discussed. An 8 cells stage, not reported for other studied species, results from two rapid successive cleavages. Blastula occurs at the eighth division when the embryo is made of 128 cells. During gastrulation, the infolded blastoderm creates the endomesoblastic layer. The Kupffer's vesicle is reported to drive the left/right patterning of brain, heart and digestive tract. Heart formation starts at 8 pairs of somites, differentiation of myotomes and sclerotomes starts at the stage 18 pairs of somites; main parts of the digestive tract are entirely formed at 25 pairs of somites. At 28 pairs of somites, a rectal region is detected, however, the digestive tube is closed at both ends, the jaw appears the fourth day after hatching, but the mouth is not opened before the fifth day. Although cardiac beating and blood circulation are observed, gills are not reported in newly hatched individuals; eye melanization appears concomitant with exotrophic behavior.

  19. FoxP2 regulates neurogenesis during embryonic cortical development.

    PubMed

    Tsui, David; Vessey, John P; Tomita, Hideaki; Kaplan, David R; Miller, Freda D

    2013-01-02

    The transcription factor FoxP2 has been associated with the development of human speech but the underlying cellular function of FoxP2 is still unclear. Here we provide evidence that FoxP2 regulates genesis of some intermediate progenitors and neurons in the mammalian cortex, one of the key centers for human speech. Specifically, knockdown of FoxP2 in embryonic cortical precursors inhibits neurogenesis, at least in part by inhibiting the transition from radial glial precursors to neurogenic intermediate progenitors. Moreover, overexpression of human, but not mouse, FoxP2 enhances the genesis of intermediate progenitors and neurons. In contrast, expression of a human FoxP2 mutant that causes vocalization deficits decreases neurogenesis, suggesting that in the murine system human FoxP2 acts as a gain-of-function protein, while a human FoxP2 mutant acts as a dominant-inhibitory protein. These results support the idea that FoxP2 regulates the transition from neural precursors to transit-amplifying progenitors and ultimately neurons, and shed light upon the molecular changes that might contribute to evolution of the mammalian cortex.

  20. Immunostaining of the developing embryonic and larval Drosophila brain.

    PubMed

    Diaper, Danielle C; Hirth, Frank

    2014-01-01

    Immunostaining is used to visualize the spatiotemporal expression pattern of developmental control genes that regulate the genesis and specification of the embryonic and larval brain of Drosophila. Immunostaining uses specific antibodies to mark expressed proteins and allows their localization to be traced throughout development. This method reveals insights into gene regulation, cell-type specification, neuron and glial differentiation, and posttranslational protein modifications underlying the patterning and specification of the maturing brain. Depending on the targeted protein, it is possible to visualize a multitude of regions of the Drosophila brain, such as small groups of neurons or glia, defined subcomponents of the brain's axon scaffold, or pre- and postsynaptic structures of neurons. Thus, antibody probes that recognize defined tissues, cells, or subcellular structures like axons or synaptic terminals can be used as markers to identify and analyze phenotypes in mutant embryos and larvae. Several antibodies, combined with different labels, can be used concurrently to examine protein co-localization. This protocol spans over 3-4 days.

  1. Embryonic development of endoderm in chicken (Gallus gallus domesticus).

    PubMed

    Alcântara, Dayane; Rodrigues, Marcio N; Franciolli, André L R; Da Fonseca, Erika T; Silva, Fernanda M O; Carvalho, Rafael C; Fratini, Paula; Sarmento, Carlos Alberto P; Ferreira, Antonio José P; Miglino, Maria Angelica

    2013-08-01

    The poultry industry is a sector of agribusiness which represents an important role in the country's agricultural exports. Therefore, the study about embryogenesis of the domestic chicken (Gallus gallus domesticus) has a great economic importance. The aim of this study was to evaluate embryonic development of the endoderm in chicken (Gallus gallus domesticus). Forty fertilized eggs of domestic chickens, starting from the 1st day of gestation and so on until the 19 days of the incubation were collected from the Granja São José (Amparo, SP, Brazil). Embryos and fetus were fixed in 10% formaldehyde solution, identified, weighed, measured, and subjected to light and scanning electron microscopy. The endoderm originates the internal lining epithelium of the digestive, immune, respiratory systems, and the organs can be visualized from the second day (48 h) when the liver is formed. The formation of the digestive system was complete in the 12th day. Respiratory system organs begin at the fourth day as a disorganized tissue and undifferentiated. Their complete differentiation was observed at the 10 days of incubation, however, until the 19 days the syrinx was not observed. The formation of immune system at 10th day was observed with observation of the spleen, thymus, and cloacal bursa. The study of the organogenesis of the chicken based on germ layers is very complex and underexplored, and the study of chicken embryology is very important due the economic importance and growth of the use of this animal model studies such as genetic studies.

  2. Critical Timing without a Timer for Embryonic Development.

    PubMed

    Tufcea, Daniel E; François, Paul

    2015-10-20

    Timing of embryonic development is precisely controlled, but the mechanisms underlying biological timers are still unclear. Here, a validated model for timing under control of Sonic Hedgehog is revisited and generalized to an arbitrary number of genes. The developmental dynamics where a temporal sequence of gene expression recapitulates a steady-state spatial pattern can be realized through a simple network close to criticality, controlled by the duration of exposure to a morphogen. Criticality simultaneously accounts for many observed biological properties, such as timing, multistability, and canalization of genetic expression. This process can be parsimoniously generalized in many dimensions with a minimum number of genes, all repressing each other with asymmetrical strengths, which also explains sequential activation of different fates. Separation of timescales allows for a simple analytical interpretation. Finally, it is shown that even in the presence of noise, coupling between cells preserves criticality and robust patterning. The model offers a simple theoretical framework for the study of emergent developmental timers. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  3. [Characterization of hematopoietic progenitor cells during the human embryonic development].

    PubMed

    Coulombel, L; Huyhn, A; Izac, B

    1995-01-01

    In a search for assays that might facilitate identification of pluripotent stem cells with extended potentialities, we analysed the properties of hematopoietic progenitor cells detected in the extraembryonic yolk sac and in the intraembryonic part of human embryos between approximately 28 and 45 days of development. Cells from the yolk sac, the liver rudiment and the remainder of the embryo were plated in semi solid methylcellulose colony-assays supplemented with combinations of cytokines. Large BFU-E-derived colonies as well as granulocytic colonies were detected in every yolk sac sample. Interestingly, progenitor cells were also detected in the intraembryonic part, outside the liver and a subclass of these progenitors were detected that generated large granulomacrophagic colonies capable of generating secondary colonies when replated. These were preferentially located in the embryo. Colony-assays initiated with CD34+ cells sorted from the different tissues confirmed these data. These results first indicate that embryonic progenitors exhibit unique phenotypic features, and second, analysis of the distribution of progenitors between the different tissues may suggest the existence of other sites of hematopoietic production. More detailed analysis of the potentialities of these progenitors should now be assessed in vitro in cocultures assays and in vivo by reconstituting immunodeficient mice.

  4. Critical Timing without a Timer for Embryonic Development

    PubMed Central

    Tufcea, Daniel E.; François, Paul

    2015-01-01

    Timing of embryonic development is precisely controlled, but the mechanisms underlying biological timers are still unclear. Here, a validated model for timing under control of Sonic Hedgehog is revisited and generalized to an arbitrary number of genes. The developmental dynamics where a temporal sequence of gene expression recapitulates a steady-state spatial pattern can be realized through a simple network close to criticality, controlled by the duration of exposure to a morphogen. Criticality simultaneously accounts for many observed biological properties, such as timing, multistability, and canalization of genetic expression. This process can be parsimoniously generalized in many dimensions with a minimum number of genes, all repressing each other with asymmetrical strengths, which also explains sequential activation of different fates. Separation of timescales allows for a simple analytical interpretation. Finally, it is shown that even in the presence of noise, coupling between cells preserves criticality and robust patterning. The model offers a simple theoretical framework for the study of emergent developmental timers. PMID:26488664

  5. Epigenetic reprogramming in embryonic and foetal development upon somatic cell nuclear transfer cloning.

    PubMed

    Niemann, Heiner; Tian, X Cindy; King, W Allan; Lee, Rita S F

    2008-02-01

    The birth of 'Dolly', the first mammal cloned from an adult donor cell, has sparked a flurry of research activities to improve cloning technology and to understand the underlying mechanism of epigenetic reprogramming of the transferred somatic cell nucleus. Especially in ruminants, somatic cell nuclear transfer (SCNT) is frequently associated with pathological changes in the foetal and placental phenotype and has significant consequences for development both before and after birth. The most critical factor is epigenetic reprogramming of the transferred somatic cell nucleus from its differentiated status into the totipotent state of the early embryo. This involves an erasure of the gene expression program of the respective donor cell and the establishment of the well-orchestrated sequence of expression of an estimated number of 10 000-12 000 genes regulating embryonic and foetal development. The following article reviews the present knowledge on the epigenetic reprogramming of the transferred somatic cell nucleus, with emphasis on DNA methylation, imprinting, X-chromosome inactivation and telomere length restoration in bovine development. Additionally, we briefly discuss other approaches towards epigenetic nuclear reprogramming, including the fusion of somatic and embryonic stem cells and the overexpression of genes crucial in the formation and maintenance of the pluripotent status. Improvements in our understanding of this dramatic epigenetic reprogramming event will be instrumental in realising the great potential of SCNT for basic biological research and for various agricultural and biomedical applications.

  6. Differential gene expression patterns during embryonic development of sea urchin exposed to triclosan.

    PubMed

    Hwang, Jinik; Suh, Sung-Suk; Park, Mirye; Park, So Yun; Lee, Sukchan; Lee, Taek-Kyun

    2017-02-01

    Triclosan (TCS; 2,4,4'-trichloro-2'-hydroxydiphenyl ether) is a broad-spectrum antibacterial agent used in common industrial, personal care and household products which are eventually rinsed down the drain and discharged with wastewater effluent. It is therefore commonly found in the aquatic environment, leading to the continual exposure of aquatic organisms to TCS and the accumulation of the antimicrobial and its harmful degradation products in their bodies. Toxic effects of TCS on reproductive and developmental progression of some aquatic organisms have been suggested but the underlying molecular mechanisms have not been defined. We investigated the expression patterns of genes involved in the early development of TCS-treated sea urchin Strongylocentrotus nudus using cDNA microarrays. We observed that the predominant consequence of TCS treatment in this model system was the widespread repression of TCS-modulated genes. In particular, empty spiracles homeobox 1 (EMX-1), bone morphogenic protein, and chromosomal binding protein genes showed a significant decrease in expression in response to TCS. These results suggest that TCS can induce abnormal development of sea urchin embryos through the concomitant suppression of a number of genes that are necessary for embryonic differentiation in the blastula stage. Our data provide new insight into the crucial role of genes associated with embryonic development in response to TCS. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 426-433, 2017. © 2016 Wiley Periodicals, Inc.

  7. RPLP1, a crucial ribosomal protein for embryonic development of the nervous system.

    PubMed

    Perucho, Laura; Artero-Castro, Ana; Guerrero, Sergi; Ramón y Cajal, Santiago; LLeonart, Matilde E; Wang, Zhao-Qi

    2014-01-01

    Ribosomal proteins are pivotal to development and tissue homeostasis. RP Large P1 (Rplp1) overexpression is associated with tumorigenesis. However, the physiological function of Rplp1 in mammalian development remains unknown. In this study, we disrupted Rplp1 in the mouse germline and central nervous system (Rplp1CNSΔ). Rplp1 heterozygosity caused body size reductions, male infertility, systemic abnormalities in various tissues and a high frequency of early postnatal death. Rplp1CNSΔ newborn mice exhibited perinatal lethality and brain atrophy with size reductions of the neocortex, midbrain and ganglionic eminence. The Rplp1 knockout neocortex exhibited progenitor cell proliferation arrest and apoptosis due to the dysregulation of key cell cycle and apoptosis regulators (cyclin A, cyclin E, p21CIP1, p27KIP1, p53). Similarly, Rplp1 deletion in pMEFs led to proliferation arrest and premature senescence. Importantly, Rplp1 deletion in primary mouse embryonic fibroblasts did not alter global protein synthesis, but did change the expression patterns of specific protein subsets involved in protein folding and the unfolded protein response, cell death, protein transport and signal transduction, among others. Altogether, we demonstrated that the translation "fine-tuning" exerted by Rplp1 is essential for embryonic and brain development and for proper cell proliferation.

  8. Thalidomide induced early gene expression perturbations indicative of human embryopathy in mouse embryonic stem cells.

    PubMed

    Gao, Xiugong; Sprando, Robert L; Yourick, Jeffrey J

    2015-08-15

    Developmental toxicity testing has traditionally relied on animal models which are costly, time consuming, and require the sacrifice of large numbers of animals. In addition, there are significant disparities between human beings and animals in their responses to chemicals. Thalidomide is a species-specific developmental toxicant that causes severe limb malformations in humans but not in mice. Here, we used microarrays to study transcriptomic changes induced by thalidomide in an in vitro model based on differentiation of mouse embryonic stem cells (mESCs). C57BL/6 mESCs were allowed to differentiate spontaneously and RNA was collected at 24, 48, and 72h after exposure to 0.25mM thalidomide. Global gene expression analysis using microarrays revealed hundreds of differentially expressed genes upon thalidomide exposure that were enriched in gene ontology (GO) terms and canonical pathways associated with embryonic development and differentiation. In addition, many genes were found to be involved in small GTPases-mediated signal transduction, heart development, and inflammatory responses, which coincide with clinical evidences and may represent critical embryotoxicities of thalidomide. These results demonstrate that transcriptomics in combination with mouse embryonic stem cell differentiation is a promising alternative model for developmental toxicity assessment.

  9. A Comparative Analysis of Transcription Factor Expression during Metazoan Embryonic Development

    PubMed Central

    Schep, Alicia N.; Adryan, Boris

    2013-01-01

    During embryonic development, a complex organism is formed from a single starting cell. These processes of growth and differentiation are driven by large transcriptional changes, which are following the expression and activity of transcription factors (TFs). This study sought to compare TF expression during embryonic development in a diverse group of metazoan animals: representatives of vertebrates (Danio rerio, Xenopus tropicalis), a chordate (Ciona intestinalis) and invertebrate phyla such as insects (Drosophila melanogaster, Anopheles gambiae) and nematodes (Caenorhabditis elegans) were sampled, The different species showed overall very similar TF expression patterns, with TF expression increasing during the initial stages of development. C2H2 zinc finger TFs were over-represented and Homeobox TFs were under-represented in the early stages in all species. We further clustered TFs for each species based on their quantitative temporal expression profiles. This showed very similar TF expression trends in development in vertebrate and insect species. However, analysis of the expression of orthologous pairs between more closely related species showed that expression of most individual TFs is not conserved, following the general model of duplication and diversification. The degree of similarity between TF expression between Xenopus tropicalis and Danio rerio followed the hourglass model, with the greatest similarity occuring during the early tailbud stage in Xenopus tropicalis and the late segmentation stage in Danio rerio. However, for Drosophila melanogaster and Anopheles gambiae there were two periods of high TF transcriptome similarity, one during the Arthropod phylotypic stage at 8–10 hours into Drosophila development and the other later at 16–18 hours into Drosophila development. PMID:23799133

  10. A comparative analysis of transcription factor expression during metazoan embryonic development.

    PubMed

    Schep, Alicia N; Adryan, Boris

    2013-01-01

    During embryonic development, a complex organism is formed from a single starting cell. These processes of growth and differentiation are driven by large transcriptional changes, which are following the expression and activity of transcription factors (TFs). This study sought to compare TF expression during embryonic development in a diverse group of metazoan animals: representatives of vertebrates (Danio rerio, Xenopus tropicalis), a chordate (Ciona intestinalis) and invertebrate phyla such as insects (Drosophila melanogaster, Anopheles gambiae) and nematodes (Caenorhabditis elegans) were sampled, The different species showed overall very similar TF expression patterns, with TF expression increasing during the initial stages of development. C2H2 zinc finger TFs were over-represented and Homeobox TFs were under-represented in the early stages in all species. We further clustered TFs for each species based on their quantitative temporal expression profiles. This showed very similar TF expression trends in development in vertebrate and insect species. However, analysis of the expression of orthologous pairs between more closely related species showed that expression of most individual TFs is not conserved, following the general model of duplication and diversification. The degree of similarity between TF expression between Xenopus tropicalis and Danio rerio followed the hourglass model, with the greatest similarity occuring during the early tailbud stage in Xenopus tropicalis and the late segmentation stage in Danio rerio. However, for Drosophila melanogaster and Anopheles gambiae there were two periods of high TF transcriptome similarity, one during the Arthropod phylotypic stage at 8-10 hours into Drosophila development and the other later at 16-18 hours into Drosophila development.

  11. Impacts of arginine nutrition on embryonic and fetal development in mammals.

    PubMed

    Wu, Guoyao; Bazer, Fuller W; Satterfield, M Carey; Li, Xilong; Wang, Xiaoqiu; Johnson, Gregory A; Burghardt, Robert C; Dai, Zhaolai; Wang, Junjun; Wu, Zhenlong

    2013-08-01

    Embryonic loss and intrauterine growth restriction (IUGR) are significant problems in humans and other animals. Results from studies involving pigs and sheep have indicated that limited uterine capacity and placental insufficiency are major factors contributing to suboptimal reproduction in mammals. Our discovery of the unusual abundance of the arginine family of amino acids in porcine and ovine allantoic fluids during early gestation led to the novel hypothesis that arginine plays an important role in conceptus (embryo and extra-embryonic membranes) development. Arginine is metabolized to ornithine, proline, and nitric oxide, with each having important physiological functions. Nitric oxide is a vasodilator and angiogenic factor, whereas ornithine and proline are substrates for uterine and placental synthesis of polyamines that are key regulators of gene expression, protein synthesis, and angiogenesis. Additionally, arginine activates the mechanistic (mammalian) target of rapamycin cell signaling pathway to stimulate protein synthesis in the placenta, uterus, and fetus. Thus, dietary supplementation with 0.83 % L-arginine to gilts consuming 2 kg of a typical gestation diet between either days 14 and 28 or between days 30 and 114 of pregnancy increases the number of live-born piglets and litter birth weight. Similar results have been reported for gestating rats and ewes. In sheep, arginine also stimulates development of fetal brown adipose tissue. Furthermore, oral administration of arginine to women with IUGR has been reported to enhance fetal growth. Collectively, enhancement of uterine as well as placental growth and function through dietary arginine supplementation provides an effective solution to improving embryonic and fetal survival and growth.

  12. Embryonic genotype and inbreeding affect preimplantation development in cattle.

    PubMed

    Lazzari, G; Colleoni, S; Duchi, R; Galli, A; Houghton, F D; Galli, C

    2011-05-01

    Infertility in cattle herds is a growing problem with multifactorial causes. Embryonic genotype and level of inbreeding are among the many factors that can play a role on reproductive efficiency. To investigate this issue, we produced purebred and crossbred bovine embryos by in vitro techniques from Holstein oocytes and Holstein or Brown Swiss semen and analyzed several cellular and molecular features. In the first experiment, purebred and crossbred embryos, obtained from abattoir oocytes, were analyzed for cleavage, development to morula/blastocyst stages, amino acid metabolism and gene expression of developmentally important genes. The results indicated significant differences in the percentage of compacted morulae, in the expression of three genes at the blastocyst stage (MNSOD, GP130 and FGF4) and in the utilization of serine, asparagine, methionine and tryptophan in day 6 embryos. In the second experiment, bovine oocytes were collected by ovum pick up from ten Holstein donors and fertilized with the semen of the respective Holstein sires or with Brown Swiss semen. The derived embryos were grown in vitro up to day 7, and were then transferred to synchronized recipients and recovered on day 12. We found that purebred/inbred embryos had lower blastocyst rate on days 7-8, were smaller on day 12 and had lower expression of the trophoblast gene PLAC8. Overall, these results indicate reduced and delayed development of purebred embryos compared with crossbred embryos. In conclusion, this study provides evidence that embryo genotype and high inbreeding can affect amino acid metabolism, gene expression, preimplantation development and therefore fertility in cattle.

  13. Engineered early embryonic cardiac tissue increases cardiomyocyte proliferation by cyclic mechanical stretch via p38-MAP kinase phosphorylation.

    PubMed

    Clause, Kelly C; Tinney, Joseph P; Liu, Li J; Keller, Bradley B; Tobita, Kimimasa

    2009-06-01

    Cardiomyocyte (CM) transplantation is one therapeutic option for cardiac repair. Studies suggest that fetal CMs display the best cell type for cardiac repair, which can finitely proliferate, integrate with injured host myocardium, and restore cardiac function. We have recently developed an engineered early embryonic cardiac tissue (EEECT) using embryonic cardiac cells and have shown that EEECT contractile properties and cellular proliferative response to cyclic mechanical stretch stimulation mimic developing fetal myocardium. However, it remains unknown whether cyclic mechanical stretch-mediated high cellular proliferation activity within EEECT reflects CM or non-CM population. Studies have shown that p38-mitogen-activated protein kinase (p38MAPK) plays an important role in both cyclic mechanical stretch stimulation and cellular proliferation. Therefore, in the present study, we tested the hypothesis that cyclic mechanical stretch (0.5 Hz, 5% strain for 48 h) specifically increases EEECT CM proliferation mediated by p38MAPK activity. Cyclic mechanical stretch increased CM, but not non-CM, proliferation and increased p38MAPK phosphorylation. Treatment of EEECT with the p38MAPK inhibitor, SB202190, reduced CM proliferation. The negative CM proliferation effects of SB202190 were not reversed by concurrent stretch stimulation. Results suggest that immature CM proliferation within EEECT can be positively regulated by mechanical stretch and negatively regulated by p38MAPK inhibition.

  14. Removal of maternal retinoic acid by embryonic CYP26 is required for correct Nodal expression during early embryonic patterning

    PubMed Central

    Uehara, Masayuki; Yashiro, Kenta; Takaoka, Katsuyoshi; Yamamoto, Masamichi; Hamada, Hiroshi

    2009-01-01

    The abundance of retinoic acid (RA) is determined by the balance between its synthesis by retinaldehyde dehydrogenase (RALDH) and its degradation by CYP26. In particular, the dynamic expression of three CYP26 genes controls the regional level of RA within the body. Pregastrulation mouse embryos express CYP26 but not RALDH. We now show that mice lacking all three CYP26 genes manifest duplication of the body axis as a result of expansion of the Nodal expression domain throughout the epiblast. Mouse Nodal was found to contain an RA-responsive element in intron 1 that is highly conserved among mammals. In the absence of CYP26, maternally derived RA activates Nodal expression in the entire epiblast of pregastrulation embryos via this element. These observations suggest that maternal RA must be removed by embryonic CYP26 for correct Nodal expression during embryonic patterning. PMID:19605690

  15. Early zebrafish development: It’s in the maternal genes

    PubMed Central

    Abrams, Elliott W.; Mullins, Mary C.

    2009-01-01

    Summary The earliest stages of embryonic development in all animals examined rely on maternal gene products that are generated during oogenesis and supplied to the egg. The period of maternal control of embryonic development varies among animals according to the onset of zygotic transcription and the persistence of maternal gene products. This maternal regulation has been little studied in vertebrates, due to the difficulty in manipulating maternal gene function and lack of basic molecular information. However, recent maternal-effect screens in the zebrafish have generated more than 40 unique mutants that are providing new molecular entry points to the maternal control of early vertebrate development. Here we discuss recent studies of 12 zebrafish mutant genes that illuminate the maternal molecular controls on embryonic development, including advances in the regulation of animal-vegetal polarity, egg activation, cleavage development, body plan formation, tissue morphogenesis, microRNA function and germ cell development. PMID:19608405

  16. Maternal dietary effects on embryonic ovarian development in cattle

    USDA-ARS?s Scientific Manuscript database

    Ovarian gametogenesis and folliculogenesis begins early in fetal development with peak numbers of follicles present in bovine fetal ovaries in the second trimester of gestation and may be altered by maternal nutrition. The objective was to determine whether maternal dietary energy intake by replacem...

  17. Regulated mitochondrial DNA replication during oocyte maturation is essential for successful porcine embryonic development.

    PubMed

    Spikings, Emma C; Alderson, Jon; St John, Justin C

    2007-02-01

    Cellular ATP is mainly generated through mitochondrial oxidative phosphorylation, which is dependent on mitochondrial DNA (mtDNA). We have previously demonstrated the importance of oocyte mtDNA for porcine and human fertilization. However, the role of nuclear-encoded mitochondrial replication factors during oocyte and embryo development is not yet understood. We have analyzed two key factors, mitochondrial transcription factor A (TFAM) and polymerase gamma (POLG), to determine their role in oocyte and early embryo development. Competent and incompetent oocytes, as determined by brilliant cresyl blue (BCB) dye, were assessed intermittently during the maturation process for TFAM and POLG mRNA using real-time RT-PCR, for TFAM and POLG protein using immunocytochemistry, and for mtDNA copy number using real-time PCR. Analysis was also carried out following treatment of maturing oocytes with the mtDNA replication inhibitor, 2',3'-dideoxycytidine (ddC). Following in vitro fertilization, preimplantation embryos were also analyzed. Despite increased levels of TFAM and POLG mRNA and protein at the four-cell stage, no increase in mtDNA copy number was observed in early preimplantation development. To compensate for this, mtDNA appeared to be replicated during oocyte maturation. However, significant differences in nuclear-encoded regulatory protein expression were observed between BCB(+) and BCB(-) oocytes and between untreated oocytes and those treated with ddC. These changes resulted in delayed mtDNA replication, which correlated to reduced fertilization and embryonic development. We therefore conclude that adherence to the regulation of the timing of mtDNA replication during oocyte maturation is essential for successful embryonic development.

  18. Rhein Induces Oxidative Stress and Apoptosis in Mouse Blastocysts and Has Immunotoxic Effects during Embryonic Development.

    PubMed

    Huang, Chien-Hsun; Chan, Wen-Hsiung

    2017-09-20

    Rhein, a glucoside chemical compound found in a traditional Chinese medicine derived from the roots of rhubarb, induces cell apoptosis and is considered to have high potential as an antitumor drug. Several previous studies showed that rhein can inhibit cell proliferation and trigger mitochondria-related or endoplasmic reticulum (ER) stress-dependent apoptotic processes. However, the side effects of rhein on pre- and post-implantation embryonic development remain unclear. Here, we show that rhein has cytotoxic effects on blastocyst-stage mouse embryos and induces oxidative stress and immunotoxicity in mouse fetuses. Blastocysts incubated with 5-20 μM rhein showed significant cell apoptosis, as well as decreases in their inner cell mass cell numbers and total cell numbers. An in vitro development assay showed that rhein affected the developmental potentials of both pre- and post-implantation embryos. Incubation of blastocysts with 5-20 μM rhein was associated with increased resorption of post-implantation embryos and decreased fetal weight in an embryo transfer assay. Importantly, in an in vivo model, intravenous injection of dams with rhein (1, 3, and 5 mg/kg body weight/day) for four days resulted in apoptosis of blastocyst-stage embryos, early embryonic developmental injury, and decreased fetal weight. Intravenous injection of dams with 5 mg/kg body weight/day rhein significantly increased the total reactive oxygen species (ROS) content of fetuses and the transcription levels of antioxidant proteins in fetal livers. Additional work showed that rhein induced apoptosis through ROS generation, and that prevention of apoptotic processes effectively rescued the rhein-induced injury effects on embryonic development. Finally, the transcription levels of the innate-immunity related genes, CXCL1, IL-1β and IL-8, were down-regulated in the fetuses of dams that received intravenous injections of rhein. These results collectively show that rhein has the potential to induce

  19. Changes in the concentrations of four maternal steroids during embryonic development in the threespined stickleback (Gasterosteus aculeatus).

    PubMed

    Paitz, Ryan Thomas; Mommer, Brett Christian; Suhr, Elissa; Bell, Alison Marie

    2015-08-01

    Embryonic exposure to steroids often leads to long-term phenotypic effects. It has been hypothesized that mothers may be able to create a steroid environment that adjusts the phenotypes of offspring to current environmental conditions. Complicating this hypothesis is the potential for developing embryos to modulate their early endocrine environment. This study utilized the threespined stickleback (Gasterosteus aculeatus) to characterize the early endocrine environment within eggs by measuring four steroids (progesterone, testosterone, estradiol, and cortisol) of maternal origin. We then examined how the concentrations of these four steroids changed over the first 12 days post fertilization (dpf). Progesterone, testosterone, estradiol, and cortisol of maternal origin could be detected within unfertilized eggs and levels of all four steroids declined in the first 3 days following fertilization. While levels of progesterone, testosterone, and estradiol remained low after the initial decline, levels of cortisol rose again by 8 dpf. These results demonstrate that G. aculeatus embryos begin development in the presence of a number of maternal steroids but levels begin to change quickly following fertilization. This suggests that embryonic processes change the early endocrine environment and hence influence the ability of maternal steroids to affect development. With these findings, G. aculeatus becomes an intriguing system in which to study how selection may act on both maternal and embryonic processes to shape the evolutionary consequence of steroid-mediated maternal effects.

  20. Prepatterning and patterning of the thalamus along embryonic development of Xenopus laevis

    PubMed Central

    Bandín, Sandra; Morona, Ruth; González, Agustín

    2015-01-01

    Previous developmental studies of the thalamus (alar part of the diencephalic prosomere p2) have defined the molecular basis for the acquisition of the thalamic competence (preparttening), the subsequent formation of the secondary organizer in the zona limitans intrathalamica, and the early specification of two anteroposterior domains (rostral and caudal progenitor domains) in response to inducing activities and that are shared in birds and mammals. In the present study we have analyzed the embryonic development of the thalamus in the anuran Xenopus laevis to determine conserved or specific features in the amphibian diencephalon. From early embryonic stages to the beginning of the larval period, the expression patterns of 22 markers were analyzed by means of combined In situ hybridization (ISH) and immunohistochemical techniques. The early genoarchitecture observed in the diencephalon allowed us to discern the boundaries of the thalamus with the prethalamus, pretectum, and epithalamus. Common molecular features were observed in the thalamic prepatterning among vertebrates in which Wnt3a, Fez, Pax6 and Xiro1 expression were of particular importance in Xenopus. The formation of the zona limitans intrathalamica was observed, as in other vertebrates, by the progressive expression of Shh. The largely conserved expressions of Nkx2.2 in the rostral thalamic domain vs. Gbx2 and Ngn2 (among others) in the caudal domain strongly suggest the role of Shh as morphogen in the amphibian thalamus. All these data showed that the molecular characteristics observed during preparttening and patterning in the thalamus of the anuran Xenopus (anamniote) share many features with those described during thalamic development in amniotes (common patterns in tetrapods) but also with zebrafish, strengthening the idea of a basic organization of this diencephalic region across vertebrates. PMID:26321920

  1. Wnt-3a is critical for caudal embryonic development

    SciTech Connect

    Camper, S.A.; Greco, T.L.; Newhouse, M.M.

    1994-09-01

    Skeletal and neural tube defects represent an important class of birth defects. The majority of mouse mutants with neural tube defects also have malformations of the tail. Vestigial tail (vt) is an autosomal recessive mouse mutation characterized by reduction or absence of the tail, vertebral abnormalities, and reduced fertility. The phenotype has been described as the result of failure of cell migration through the primitive streak, causing abnormalities in the development of the neural tube and a reduction in the ventral ectodermal ridge. Wnt3a is an excellent candidate gene for vt because Wnt3a is expressed in the primitive streak and in the embryonic mesoderm, and it is thought to be involved in cell-to-cell communication and formation of the dorsal-ventral axis in the CNS. A lack of Wnt3a might be expected to result in overdorsalization of the neural tube and reduction of the ventral ectodermal ridge characteristic of vt/vt embryos. In a high resolution backcross segregating vt, we observed no recombination between vt and Wnt3a in 363 individuals analyzed. In vt/vt mice, Southern blot analysis revealed no abnormalities in the Wnt3a gene, and the Wnt3a cDNA sequence does not encode any amino acid changes. Whole mount in situ hybridization analysis demonstrated that Wnt3a expression is severely reduced in the developing tailbud of day 9.5 vt/vt embryos, suggestive of a lesion in the regulation on Wnt3a expression. An alleleism test, carried out by mating vt/vt males with Wnt3a +/Wnt3a- females, demonstrated that vt and Wnt3a are noncomplementing alleles. All of the compound heterozygotes exhibited severe tail defects, including occasional examples of hind limb parlaysis and spina bifida. The vertebral defects are intermediate between those of vt and Wnt3a homozygotes, suggesting that the concentration of Wnt3a correlates with the severity of the defect.

  2. Visualization of an endogenous retinoic acid gradient across embryonic development.

    PubMed

    Shimozono, Satoshi; Iimura, Tadahiro; Kitaguchi, Tetsuya; Higashijima, Shin-Ichi; Miyawaki, Atsushi

    2013-04-18

    In vertebrate development, the body plan is determined by primordial morphogen gradients that suffuse the embryo. Retinoic acid (RA) is an important morphogen involved in patterning the anterior-posterior axis of structures, including the hindbrain and paraxial mesoderm. RA diffuses over long distances, and its activity is spatially restricted by synthesizing and degrading enzymes. However, gradients of endogenous morphogens in live embryos have not been directly observed; indeed, their existence, distribution and requirement for correct patterning remain controversial. Here we report a family of genetically encoded indicators for RA that we have termed GEPRAs (genetically encoded probes for RA). Using the principle of fluorescence resonance energy transfer we engineered the ligand-binding domains of RA receptors to incorporate cyan-emitting and yellow-emitting fluorescent proteins as fluorescence resonance energy transfer donor and acceptor, respectively, for the reliable detection of ambient free RA. We created three GEPRAs with different affinities for RA, enabling the quantitative measurement of physiological RA concentrations. Live imaging of zebrafish embryos at the gastrula and somitogenesis stages revealed a linear concentration gradient of endogenous RA in a two-tailed source-sink arrangement across the embryo. Modelling of the observed linear RA gradient suggests that the rate of RA diffusion exceeds the spatiotemporal dynamics of embryogenesis, resulting in stability to perturbation. Furthermore, we used GEPRAs in combination with genetic and pharmacological perturbations to resolve competing hypotheses on the structure of the RA gradient during hindbrain formation and somitogenesis. Live imaging of endogenous concentration gradients across embryonic development will allow the precise assignment of molecular mechanisms to developmental dynamics and will accelerate the application of approaches based on morphogen gradients to tissue engineering and

  3. Chromosomal anomaly spectrum in early pregnancy loss in relation to presence or absence of an embryonic pole.

    PubMed

    Muñoz, Monica; Arigita, Marta; Bennasar, Mar; Soler, Anna; Sanchez, Aurora; Borrell, Antoni

    2010-12-01

    To compare the cytogenetic findings in a series of missed miscarriages evaluated by chorionic villus sampling, in relation to embryonic pole presence (embryonic or anembryonic). Prospective cross-sectional study. Tertiary referral hospital. Women presenting with a missed miscarriage. Transcervical chorionic villus sampling and cytogenetic studies in the chorionic villi with use of the semidirect method. Embryonic pole presence or absence assessed by transvaginal ultrasound examination. Type of chromosomal anomalies found in both subgroups. Although the chromosomal abnormality rate was similar for miscarriages with absent or present embryo (61% vs. 68% respectively), frequencies for viable autosomal trisomies (2.3% vs. 19%) and monosomy X (0% vs. 9.2%) were significantly lower when no embryonic pole was seen. Viable autosomal trisomies and monosomies X appear not to be a common cause of miscarriage with an early fetal demise (anembryonic miscarriage). Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  4. Serial block face-scanning electron microscopy: a tool for studying embryonic development at the cell-matrix interface.

    PubMed

    Starborg, Tobias; Kadler, Karl E

    2015-03-01

    Studies of gene regulation, signaling pathways, and stem cell biology are contributing greatly to our understanding of early embryonic vertebrate development. However, much less is known about the events during the latter half of embryonic development, when tissues comprising mostly extracellular matrix (ECM) are formed. The matrix extends far beyond the boundaries of individual cells and is refractory to study by conventional biochemical and molecular techniques; thus major gaps exist in our knowledge of the formation and three-dimensional (3D) organization of the dense tissues that form the bulk of adult vertebrates. Serial block face-scanning electron microscopy (SBF-SEM) has the ability to image volumes of tissue containing numerous cells at a resolution sufficient to study the organization of the ECM. Furthermore, whereas light microscopy was once relatively straightforward and electron microscopy was performed in specialist laboratories, the tables are turned; SBF-SEM is relatively straightforward and is becoming routine in high-end resolution studies of embryonic structures in vivo. In this review, we discuss the emergence of SBF-SEM as a tool for studying embryonic vertebrate development.

  5. Boolean genetic network model for the control of C. elegans early embryonic cell cycles

    PubMed Central

    2013-01-01

    Background In Caenorhabditis elegans early embryo, cell cycles only have two phases: DNA synthesis and mitosis, which are different from the typical 4-phase cell cycle. Modeling this cell-cycle process into network can fill up the gap in C. elegans cell-cycle study and provide a thorough understanding on the cell-cycle regulations and progressions at the network level. Methods In this paper, C. elegans early embryonic cell-cycle network has been constructed based on the knowledge of key regulators and their interactions from literature studies. A discrete dynamical Boolean model has been applied in computer simulations to study dynamical properties of this network. The cell-cycle network is compared with random networks and tested under several perturbations to analyze its robustness. To investigate whether our proposed network could explain biological experiment results, we have also compared the network simulation results with gene knock down experiment data. Results With the Boolean model, this study showed that the cell-cycle network was stable with a set of attractors (fixed points). A biological pathway was observed in the simulation, which corresponded to a whole cell-cycle progression. The C. elegans network was significantly robust when compared with random networks of the same size because there were less attractors and larger basins than random networks. Moreover, the network was also robust under perturbations with no significant change of the basin size. In addition, the smaller number of attractors and the shorter biological pathway from gene knock down network simulation interpreted the shorter cell-cycle lengths in mutant from the RNAi gene knock down experiment data. Hence, we demonstrated that the results in network simulation could be verified by the RNAi gene knock down experiment data. Conclusions A C. elegans early embryonic cell cycles network was constructed and its properties were analyzed and compared with those of random networks

  6. Patterns in early embryonic motility: effects of size and environmental temperature on vertical velocities of sinking and swimming echinoid blastulae.

    PubMed

    McDonald, Kathryn

    2004-10-01

    Early embryonic swimming is widespread among marine invertebrates, but quantitative information about swimming behaviors is scarce. Swimming may affect encounters with predators, positioning in the water column, and nutrient absorption. Measured rates and patterns of swimming and sinking for blastulae of four eastern Pacific echinoid species show that sinking speeds equal or exceed swimming speeds. Swimming speed scaled negatively with embryo size, though sinking speed did not scale with size. Analysis of swimming paths of Strongylocentrotus franciscanus revealed a temperature dependency in swimming pattern that affected speed of upward movement. Sinking speeds were significantly greater at 10 degrees C than at 14 degrees C for blastulae of all four species examined. In Dendraster excentricus, killing the blastulae annulled this temperature effect, indicating an active density regulation by these embryos. Finally, measurements of particle velocities around sinking and swimming D. excentricus blastulae show that swimming creates a more localized disturbance than sinking. Embryonic swimming may therefore decrease rather than increase encounters with pelagic predators. Results from subsequent experiments in which embryos were reared in low-oxygen environments suggest that any oxygen-absorption advantages of swimming have little, if any, effect on the development of D. excentricus embryos.

  7. Interaction between SCO-spondin and low density lipoproteins from embryonic cerebrospinal fluid modulates their roles in early neurogenesis.

    PubMed

    Vera, América; Recabal, Antonia; Saldivia, Natalia; Stanic, Karen; Torrejón, Marcela; Montecinos, Hernán; Caprile, Teresa

    2015-01-01

    During early stages of development, encephalic vesicles are composed by a layer of neuroepithelial cells surrounding a central cavity filled with embryonic cerebrospinal fluid (eCSF). This fluid contains several morphogens that regulate proliferation and differentiation of neuroepithelial cells. One of these neurogenic factors is SCO-spondin, a giant protein secreted to the eCSF from early stages of development. Inhibition of this protein in vivo or in vitro drastically decreases the neurodifferentiation process. Other important neurogenic factors of the eCSF are low density lipoproteins (LDL), the depletion of which generates a 60% decrease in mesencephalic explant neurodifferentiation. The presence of several LDL receptor class A (LDLrA) domains (responsible for LDL binding in other proteins) in the SCO-spondin sequence suggests a possible interaction between both molecules. This possibility was analyzed using three different experimental approaches: (1) Bioinformatics analyses of the SCO-spondin region, that contains eight LDLrA domains in tandem, and of comparisons with the LDL receptor consensus sequence; (2) Analysis of the physical interactions of both molecules through immunohistochemical colocalization in embryonic chick brains and through the immunoprecipitation of LDL with anti-SCO-spondin antibodies; and (3) Analysis of functional interactions during the neurodifferentiation process when these molecules were added to a culture medium of mesencephalic explants. The results revealed that LDL and SCO-spondin interact to form a complex that diminishes the neurogenic capacities that both molecules have separately. Our work suggests that the eCSF is an active signaling center with a complex regulation system that allows for correct brain development.

  8. Interaction between SCO-spondin and low density lipoproteins from embryonic cerebrospinal fluid modulates their roles in early neurogenesis

    PubMed Central

    Vera, América; Recabal, Antonia; Saldivia, Natalia; Stanic, Karen; Torrejón, Marcela; Montecinos, Hernán; Caprile, Teresa

    2015-01-01

    During early stages of development, encephalic vesicles are composed by a layer of neuroepithelial cells surrounding a central cavity filled with embryonic cerebrospinal fluid (eCSF). This fluid contains several morphogens that regulate proliferation and differentiation of neuroepithelial cells. One of these neurogenic factors is SCO-spondin, a giant protein secreted to the eCSF from early stages of development. Inhibition of this protein in vivo or in vitro drastically decreases the neurodifferentiation process. Other important neurogenic factors of the eCSF are low density lipoproteins (LDL), the depletion of which generates a 60% decrease in mesencephalic explant neurodifferentiation. The presence of several LDL receptor class A (LDLrA) domains (responsible for LDL binding in other proteins) in the SCO-spondin sequence suggests a possible interaction between both molecules. This possibility was analyzed using three different experimental approaches: (1) Bioinformatics analyses of the SCO-spondin region, that contains eight LDLrA domains in tandem, and of comparisons with the LDL receptor consensus sequence; (2) Analysis of the physical interactions of both molecules through immunohistochemical colocalization in embryonic chick brains and through the immunoprecipitation of LDL with anti-SCO-spondin antibodies; and (3) Analysis of functional interactions during the neurodifferentiation process when these molecules were added to a culture medium of mesencephalic explants. The results revealed that LDL and SCO-spondin interact to form a complex that diminishes the neurogenic capacities that both molecules have separately. Our work suggests that the eCSF is an active signaling center with a complex regulation system that allows for correct brain development. PMID:26074785

  9. Distinct regulators for Plk1 activation in starfish meiotic and early embryonic cycles

    PubMed Central

    Okano-Uchida, Takayuki; Okumura, Eiichi; Iwashita, Motoko; Yoshida, Hitoshi; Tachibana, Kazunori; Kishimoto, Takeo

    2003-01-01

    The Polo-like kinase, Plk, has multiple roles in regulating mitosis. In particular, Plk1 has been postulated to function as a trigger kinase that phosphorylates and activates Cdc25C prior to the activation of cyclin B–Cdc2 and thereby initiates its activation. However, the upstream regulation of Plk1 activation remains unclear. Here we have studied the interplay between Plk1 and Cdc2 through meiotic and early embryonic cycles in starfish. Distinct kinases, cyclin B–Cdc2, MAPK along with cyclin B– and/or cyclin A–Cdc2 and cyclin A–Cdc2, were unique upstream regulators for Plk1 activation at meiosis I, meiosis II and embryonic M-phase, respectively, indicating that Plk1 is not the trigger kinase at meiotic reinitiation. When Plk1 was required for cyclin B–Cdc2 activation, the action of Plk1 was mediated primarily through suppression of Myt1 rather than through activation of Cdc25. We propose that Plk1 can be activated by either cyclin A– or cyclin B–Cdc2, and its primary target is Myt1. PMID:14532135

  10. Adverse Outcome Pathway for Embryonic Vascular Disruption and Alternative Methods to Identify Chemical Vascular Disruptors During Development

    EPA Science Inventory

    Chemically induced vascular toxicity during embryonic development can result in a wide range of adverse prenatal outcomes. We used information from genetic mouse models linked to phenotypic outcomes and a vascular toxicity knowledge base to construct an embryonic vascular disrupt...

  11. Adverse Outcome Pathway for Embryonic Vascular Disruption and Alternative Methods to Identify Chemical Vascular Disruptors During Development

    EPA Science Inventory

    Chemically induced vascular toxicity during embryonic development can result in a wide range of adverse prenatal outcomes. We used information from genetic mouse models linked to phenotypic outcomes and a vascular toxicity knowledge base to construct an embryonic vascular disrupt...

  12. Effect of rearing temperatures during embryonic development on the phenotypic sex in zebrafish (Danio rerio).

    PubMed

    Abozaid, H; Wessels, S; Hörstgen-Schwark, G

    2011-01-01

    In zebrafish, Danio rerio, a polygenic pattern of sex determination or a female heterogamety with possible influences of environmental factors is assumed. The present study focuses on the effects of an elevated water temperature (35° C) during the embryonic development on sex determination in zebrafish. Eggs derived from 3 golden females were fertilized by the same mitotic gynogenetic male and exposed to a water temperature of 35° C, applied from 5 to 10 h post fertilization (hpf), from 5 to 24 hpf, and from 5 to 48 hpf, which correspond to the following developmental stages: gastrula, gastrula to segmentation, and gastrula to pharyngula stage, respectively. Hatching and survival rates decreased with increasing exposure to high water temperatures. Reductions in the hatching and survival rates were not responsible for differences in sex ratios. Accordingly, exposition of the fertilized eggs to a high temperature (35° C) leads to an increase of the male proportion from 22.0% in the controls to a balanced sex ratio (48.3, 47.5, and 52.6%) in the gastrula, segmentation, and pharyngula groups, respectively. These results prove the possibility to change the pathway of sexual determination during early embryonic stages in zebrafish by exposure to a high water temperature.

  13. Aspects of embryonic and larval development in bighead carp Hypophthalmichthys nobilis and silver carp Hypophthalmichthys molitrix.

    PubMed

    George, Amy E; Chapman, Duane C

    2013-01-01

    As bighead carp Hypophthalmichthysnobilis and silver carp H. molitrix (the bigheaded carps) are poised to enter the Laurentian Great Lakes and potentially damage the region's economically important fishery, information on developmental rates and behaviors of carps is critical to assessing their ability to establish sustainable populations within the Great Lakes basin. In laboratory experiments, the embryonic and larval developmental rates, size, and behaviors of bigheaded carp were tracked at two temperature treatments, one "cold" and one "warm". Developmental rates were computed using previously described stages of development and the cumulative thermal unit method. Both species have similar thermal requirements, with a minimum developmental temperature for embryonic stages of 12.1° C for silver carp and 12.9° C for bighead carp, and 13.3° C for silver carp larval stages and 13.4° C for bighead carp larval stages. Egg size differed among species and temperature treatments, as egg size was larger in bighead carp, and "warm" temperature treatments. The larvae started robust upwards vertical swimming immediately after hatching, interspersed with intervals of sinking. Vertical swimming tubes were used to measure water column distribution, and ascent and descent rates of vertically swimming fish. Water column distribution and ascent and descent rates changed with ontogeny. Water column distribution also showed some diel periodicity. Developmental rates, size, and behaviors contribute to the drift distance needed to fulfill the early life history requirements of bigheaded carps and can be used in conjunction with transport information to assess invasibility of a river.

  14. Elevated CO2 affects embryonic development and larval phototaxis in a temperate marine fish.

    PubMed

    Forsgren, Elisabet; Dupont, Sam; Jutfelt, Fredrik; Amundsen, Trond

    2013-10-01

    As an effect of anthropogenic CO2 emissions, the chemistry of the world's oceans is changing. Understanding how this will affect marine organisms and ecosystems are critical in predicting the impacts of this ongoing ocean acidification. Work on coral reef fishes has revealed dramatic effects of elevated oceanic CO2 on sensory responses and behavior. Such effects may be widespread but have almost exclusively been tested on tropical reef fishes. Here we test the effects elevated CO2 has on the reproduction and early life history stages of a temperate coastal goby with paternal care by allowing goby pairs to reproduce naturally in an aquarium with either elevated (ca 1400 μatm) CO2 or control seawater (ca 370 μatm CO2). Elevated CO2 did not affect the occurrence of spawning nor clutch size, but increased embryonic abnormalities and egg loss. Moreover, we found that elevated CO2 significantly affected the phototactic response of newly hatched larvae. Phototaxis is a vision-related fundamental behavior of many marine fishes, but has never before been tested in the context of ocean acidification. Our findings suggest that ocean acidification affects embryonic development and sensory responses in temperate fishes, with potentially important implications for fish recruitment.

  15. Elevated CO2 affects embryonic development and larval phototaxis in a temperate marine fish

    PubMed Central

    Forsgren, Elisabet; Dupont, Sam; Jutfelt, Fredrik; Amundsen, Trond

    2013-01-01

    As an effect of anthropogenic CO2 emissions, the chemistry of the world's oceans is changing. Understanding how this will affect marine organisms and ecosystems are critical in predicting the impacts of this ongoing ocean acidification. Work on coral reef fishes has revealed dramatic effects of elevated oceanic CO2 on sensory responses and behavior. Such effects may be widespread but have almost exclusively been tested on tropical reef fishes. Here we test the effects elevated CO2 has on the reproduction and early life history stages of a temperate coastal goby with paternal care by allowing goby pairs to reproduce naturally in an aquarium with either elevated (ca 1400 μatm) CO2 or control seawater (ca 370 μatm CO2). Elevated CO2 did not affect the occurrence of spawning nor clutch size, but increased embryonic abnormalities and egg loss. Moreover, we found that elevated CO2 significantly affected the phototactic response of newly hatched larvae. Phototaxis is a vision-related fundamental behavior of many marine fishes, but has never before been tested in the context of ocean acidification. Our findings suggest that ocean acidification affects embryonic development and sensory responses in temperate fishes, with potentially important implications for fish recruitment. PMID:24198929

  16. The rhox homeobox gene family shows sexually dimorphic and dynamic expression during mouse embryonic gonad development.

    PubMed

    Daggag, Hinda; Svingen, Terje; Western, Patrick S; van den Bergen, Jocelyn A; McClive, Peter J; Harley, Vincent R; Koopman, Peter; Sinclair, Andrew H

    2008-09-01

    Reproductive capacity is fundamental to the survival of all species. Consequently, much research has been undertaken to better understand gametogenesis and the interplay between germ cells and the somatic cell lineages of the gonads. In this study, we have analyzed the embryonic expression pattern of the X-linked gene family Reproductive homeobox genes on the X chromosome (Rhox) in mice. Our data show that eight members of the Rhox gene family are developmentally regulated in sexually dimorphic and temporally dynamic patterns in the developing germ cells during early gonadogenesis. These changes coincide with critical stages of differentiation where the germ cells enter either mitotic arrest in the testis or meiotic arrest in the ovary. Finally, we show that Rhox8 (Tox) is the only member of the Rhox gene family that is expressed in the somatic compartment of the embryonic gonads. Our results indicate that the regulation of Rhox gene expression and its potential function during embryogenesis are quite distinct from those previously reported for Rhox gene regulation in postnatal gonads.

  17. Human fetal liver stromal cells expressing erythropoietin promote hematopoietic development from human embryonic stem cells.

    PubMed

    Yang, Chao; Ji, Lei; Yue, Wen; Shi, Shuang-Shuang; Wang, Ruo-Yong; Li, Yan-Hua; Xie, Xiao-Yan; Xi, Jia-Fei; He, Li-Juan; Nan, Xue; Pei, Xue-Tao

    2012-02-01

    Blood cells transfusion and hematopoietic stem cells (HSCs) transplantation are important methods for cell therapy. They are widely used in the treatment of incurable hematological disorder, infectious diseases, genetic diseases, and immunologic deficiency. However, their availability is limited by quantity, capacity of proliferation and the risk of blood transfusion complications. Recently, human embryonic stem cells (hESCs) have been shown to be an alternative resource for the generation of hematopoietic cells. In the current study, we describe a novel method for the efficient production of hematopoietic cells from hESCs. The stable human fetal liver stromal cell lines (hFLSCs) expressing erythropoietin (EPO) were established using the lentiviral system. We observed that the supernatant from the EPO transfected hFLSCs could induce the hESCs differentiation into hematopoietic cells, especially erythroid cells. They not only expressed fetal and embryonic globins but also expressed the adult-globin chain on further maturation. In addition, these hESCs-derived erythroid cells possess oxygen-transporting capacity, which indicated hESCs could generate terminally mature progenies. This should be useful for ultimately developing an animal-free culture system to generate large numbers of erythroid cells from hESCs and provide an experimental model to study early human erythropoiesis.

  18. Embryonic development of the nervous system in the planarian Schmidtea polychroa.

    PubMed

    Monjo, Francisco; Romero, Rafael

    2015-01-15

    The development of a nervous system is a key innovation in the evolution of metazoans, which is illustrated by the presence of a common developmental toolkit for the formation of this organ system. Neurogenesis in the Spiralia, in particular the Platyhelminthes, is, however, poorly understood when compared with other animal groups. Here, we characterize embryonic neurogenesis in the freshwater flatworm Schmidtea polychroa and analyze the expression of soxB and a set of proneural bHLH genes, which are gene families with a well-established role in metazoan early neural development. We show that the nervous system is fully de novo assembled after the early embryo ingests the maternal nutrients. At early stages of neurogenesis, soxB1 genes are expressed in putative neural progenitor cells, whereas soxB2 and neural bHLH genes (achaete-scute, neuroD and beta3) are associated with late neurogenesis and the specification of neural subpopulations of the central and peripheral nervous system. Our findings are consistent with the role of proneural genes in other bilaterians, suggesting that the ancestral neural-specific gene regulatory network is conserved in triclads, despite exhibiting a divergent mode of development.

  19. Surviving a flood: effects of inundation period, temperature and embryonic development stage in locust eggs.

    PubMed

    Woodman, J D

    2015-08-01

    The Australian plague locust, Chortoicetes terminifera (Walker), is an important agricultural pest and oviposits into compacted soil across vast semi-arid and arid regions prone to irregular heavy summer rainfall. This study aimed to quantify the effects of flooding (control, 7, 14, 21, 28 and 35 days) at different temperatures (15, 20 and 25°C) and embryonic development stages (25 and 75%) on egg viability, hatchling nymph body mass and survival to second-instar. Egg viability after flooding was dependent on temperature and flood duration. Eggs inundated at 15°C showed ≥53.5% survival regardless of flood duration and development stage compared with ≤29.6% for eggs at 25°C for ≥21 days early in development and ≥14 days late in development. Hatchling nymphs did not differ in body mass relative to temperature or flood duration, but weighed more from eggs inundated early in development rather than late. Survival to second-instar was ≤55.1% at 15 and 20°C when eggs were flooded for ≥28 days late in development, ≤35.6% at 25°C when flooded for ≥28 days early in development, and zero when flooded for ≥21 days late in development. These results suggest that prolonged flooding in summer and early autumn may cause very high egg mortality and first-instar nymph mortality of any survivors, but is likely to only ever affect a small proportion of the metapopulation. More common flash flooding for ≤14 days is unlikely to cause high mortality and have any direct effect on distribution and abundance.

  20. Parthenogenesis in unfertilized eggs of Coturnix chinensis, the Chinese painted quail, and the effect of egg clutch position on embryonic development.

    PubMed

    Parker, H M; McDaniel, C D

    2009-04-01

    Parthenogenesis, embryonic development of an unfertilized egg, was studied for many years in turkeys. In fact, as many as 49% of unfertilized Beltsville Small White turkey eggs develop embryos. However, no research exists on parthenogenesis in quail. The Chinese painted quail is a close relative of the more common Japanese quail and, unlike turkeys or chickens, the small Chinese painted quail reaches sexual maturity rapidly, making it a great candidate for further research on parthenogenesis. Obviously, a better understanding of avian parthenogenesis should increase our knowledge of avian fertilization and early embryonic development. Therefore, we determined if unfertilized Chinese painted quail hens produce embryos. Second, we explored the possibility that position of the egg within the clutch influences parthenogenesis. When initial secondary sexual plumage was apparent at 4 wk of age, male chicks were separated from females to prevent fertilization. Hens were placed in individual cages near sexual maturity, at approximately 6 wk of age. Individual eggs were collected daily and labeled with hen number and date. Eggs were stored for 0 to 3 d at 20 degrees C before incubation at 37.5 degrees C. After 10 d of incubation, approximately 4,000 eggs from 300 laying hens were examined for embryonic development under a magnifying lamp. On average, 4.8% of the unfertilized eggs contained an abortive form of embryonic development consisting of undifferentiated cells and unorganized membranes. Approximately 27% of the laying hens produced at least 1 egg with parthenogenic development. However, about 10% (30) of these hens exhibited a predisposition for parthenogenesis by producing 2 or more unfertilized eggs with embryonic development. Twenty percent of the eggs from 2 hens produced embryonic development. Additionally, the first egg laid in a clutch was most likely to produce embryonic development, with a steady decline in the percentage of eggs with embryonic development

  1. From Embryonic Development to Human Diseases: The Functional Role of Caveolae/Caveolin

    PubMed Central

    Sohn, Jihee; Brick, Rachel M.; Tuan, Rocky S.

    2017-01-01

    Caveolae, an almost ubiquitous, structural component of the plasma membrane, play a critical role in many functions essential for proper cell function, including membrane trafficking, signal transduction, extracellular matrix remodeling, and tissue regeneration. Three main types of caveolin proteins have been identified from caveolae since the discovery of caveolin-1 in the early 1990s. All three (Cav-1, Cav-2, and Cav-3) play crucial roles in mammalian physiology, and can effect pathogenesis in a wide range of human diseases. While many biological activities of caveolins have been uncovered since its discovery, their role and regulation in embryonic develop remain largely poorly understood, although there is increasing evidence that caveolins may be linked to lung and brain birth defects. Further investigations are clearly needed to decipher how caveolae/caveolins mediate cellular functions and activities of normal embryogenesis and how their perturbations contribute to developmental disorders. PMID:26991990

  2. Early Interactive Emotional Development

    PubMed Central

    Messinger, Daniel S.; Mahoor, Mohammad H.; Cadavid, Steven; Chow, Sy-Miin; Cohn, Jeffrey F.

    2010-01-01

    Early infant emotional development concerns the interactive emergence of emotional states that motivate approach and withdrawal. These are indexed by different patterns of infant facial expressions, vocalization, and gazing that emerge within parent-infant interactions in the first 10 months of life. Specifically, the interface of a limited number of interactive parameters creates complex real-time patterns which change over developmental time. These phenomena are described below using techniques from our laboratory such as statistical simulations, continuous ratings, and computer vision modeling. PMID:21804955

  3. Development of sympathetic cardiovascular control in embryonic, hatchling, and yearling female American alligator (Alligator mississippiensis).

    PubMed

    Eme, John; Elsey, Ruth M; Crossley, Dane A

    2013-06-01

    We used arterial tyramine injections to study development of sympathetic actions on in vivo heart rate and blood pressure in embryonic, hatching and yearling female American alligators. Tyramine is a pharmacological tool for understanding comparative and developmental sympathetic regulation of cardiovascular function, and this indirect sympathomimetic agent causes endogenous neuronal catecholamine release, increasing blood pressure and heart rate. Arterial tyramine injection in hatchling and yearling alligators caused the typical vertebrate response - rise in heart rate and blood pressure. However, in embryonic alligators, tyramine caused a substantial and immediate bradycardia at both 70% and 90% of embryonic development. This embryonic bradycardia was accompanied by hypotension, followed by a sustained hypertension similar to the hatchling and juvenile responses. Pretreatment with atropine injection (cholinergic receptor blocker) eliminated the embryonic hypotensive bradycardia, and phentolamine pretreatment (α-adrenergic receptor blocker) eliminated the embryonic hypotensive and hypertensive responses but not the bradycardia. In addition, hexamethonium pretreatment (nicotinic receptor blocker) significantly blunted embryos' bradycardic tyramine response. However, pretreatment with 6-hydroxydopamine, a neurotoxin that destroys catecholaminergic terminals, did not eliminate the embryonic bradycardia. Tyramine likely stimulated a unique embryonic response - neurotransmitter release from preganglionic nerve terminals (blocked with hexamethonium) and an acetylcholine mediated bradycardia with a secondary norepinephrine-dependent sustained hypertension. In addition, tyramine appears to stimulate sympathetic nerve terminals directly, which contributed to the overall hypertension in the embryonic, hatchling and yearling animals. Data demonstrated that humoral catecholamine control of cardiovascular function was dominant over the immature parasympathetic nervous system

  4. [Embryonic development of whitefishes (Coregonidae) as representatives of the "pagophilous" ecological group].

    PubMed

    Cherniaev, Zh A

    2013-01-01

    Studies of reproduction and embryonic development in six species of coregonid fishes have revealed the possibility of their fertilized eggs to develop normally while being embedded in the ice of a spawning water body (optionally). Such ability is facilitated by extremely low respiratory activity of embryos at early stages of embryogenesis (from the stage of fission to the stage of organogenesis). Low level of oxygen consumption and carbon dioxide emission is an adaptation to low diffusion gas permeability of the ice. The main factor controlling the rate of coregonids embryonic development is not temperature, but intensity and periodicity of insolation. Without the sunlight--an obligatory external factor--normal development is just not possible. Under experimental conditions, when developing in the water at near zero temperature or in the ice, normal morphogenesis of Arctic cisco and Sevan whitefish embryos was observed at the illumination of 50-300 lux. Hemoproteid cytochrome beta560, the pigment that has been discovered in water-soluble part of coregonids oocyte yolk and is treated as a biochemical marker for eggs of the family Coregonidae, in all likelihood performs protective (antioxidant) functions preventing spontaneous oxidation of embryo's fatty inclusions. Under the oxygen shortage inside the ice envelope, cytochrome beta560 probably sets conditions for oxidation processes of embryo's tissue respiration. Spherome, being kept till the time of hatching, acts as a temporary hydrostatic organ and ensures larvae buoyancy at the stage of postembryonic metamorphosis. It also serves as an energy store after downstream migration of larvae from the spawning areas till their shift to exogenous feeding on zooplankton. Conforming to ecological traits of reproduction and development, and also to revealed morphogenetic, physiological, and biochemical features, it is proposed to ascribe all of the currently known 26 species of whitefishes to "pagophilous" ecological group.

  5. Butyl benzyl phthalate (BBP) induces caudal defects during embryonic development.

    PubMed

    Roy, Nicole M; Zambrzycka, Ewelina; Santangelo, Jenna

    2017-09-18

    Butyl benzyl phthalate (BBP) is commonly added during the manufacturing of plastics to increase flexibility and elasticity. However, BBP leaches off of plastic and environment presence has been detected in soil, groundwater and sediment potentially effecting organisms in the environment. Given the widespread uses of BBP in household, consumer goods and the presence of BBP in the environment, studies on developmental toxicity are needed. Here, we use a zebrafish model to investigate the early developmental toxicity of BBP. We treated gastrula staged embryos with increasing concentrations of BBP and noted concentration-dependent defects in caudal tail development, but the effect was caudal specific with no other developmental defects noted. In situ hybridization studies using muscle and notochord markers show alterations in muscle development and non-linear, kinked notochord staining. A more detailed antibody staining using a myosin specific marker shows disorganized myofibrils and a loss of chevron shaped somites. Furthermore, vascular development in the tail was also disrupted in a concentration dependent manner. We conclude that BBP is toxic to caudal development in zebrafish. The sensitivity of zebrafish during development to environmental toxins and chemicals has been useful in assessing the health of the aquatic environment. The results presented here are a useful early warning system for contamination that could affect human health. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Spatial expression of transcription factors in Drosophila embryonic organ development.

    PubMed

    Hammonds, Ann S; Bristow, Christopher A; Fisher, William W; Weiszmann, Richard; Wu, Siqi; Hartenstein, Volker; Kellis, Manolis; Yu, Bin; Frise, Erwin; Celniker, Susan E

    2013-12-20

    Site-specific transcription factors (TFs) bind DNA regulatory elements to control expression of target genes, forming the core of gene regulatory networks. Despite decades of research, most studies focus on only a small number of TFs and the roles of many remain unknown. We present a systematic characterization of spatiotemporal gene expression patterns for all known or predicted Drosophila TFs throughout embryogenesis, the first such comprehensive study for any metazoan animal. We generated RNA expression patterns for all 708 TFs by in situ hybridization, annotated the patterns using an anatomical controlled vocabulary, and analyzed TF expression in the context of organ system development. Nearly all TFs are expressed during embryogenesis and more than half are specifically expressed in the central nervous system. Compared to other genes, TFs are enriched early in the development of most organ systems, and throughout the development of the nervous system. Of the 535 TFs with spatially restricted expression, 79% are dynamically expressed in multiple organ systems while 21% show single-organ specificity. Of those expressed in multiple organ systems, 77 TFs are restricted to a single organ system either early or late in development. Expression patterns for 354 TFs are characterized for the first time in this study. We produced a reference TF dataset for the investigation of gene regulatory networks in embryogenesis, and gained insight into the expression dynamics of the full complement of TFs controlling the development of each organ system.

  7. DNA methylation, an epigenetic mechanism connecting folate to healthy embryonic development and aging

    PubMed Central

    Kim, Kyong-chol; Friso, Simonetta; Choi, Sang-Woon

    2009-01-01

    Experimental studies demonstrated that maternal exposure to certain environmental and dietary factors during early embryonic development can influence the phenotype of offspring as well as the risk of disease development at the later life. DNA methylation, an epigenetic phenomenon, has been suggested as a mechanism by which maternal nutrients affect the phenotype of their offspring in both honeybee and agouti mouse models. Phenotypic changes through DNA methylation can be linked to folate metabolism by the knowledge that folate, a coenzyme of one-carbon metabolism, is directly involved in methyl group transfer for DNA methylation. During the fetal period, organ-specific DNA methylation patterns are established through epigenetic reprogramming. However, established DNA methylation patterns are not immutable and can be modified during our life time by the environment. Aberrant changes in DNA methylation with diet may lead to the development of age-associated diseases including cancer. It is also known that the aging process by itself is accompanied by alterations in DNA methylation. Diminished activity of DNA methyltransferases (Dnmts) can be a potential mechanism for the decreased genomic DNA methylation during aging, along with reduced folate intake and altered folate metabolism. Progressive hypermethylation in promoter regions of certain genes is observed throughout aging and repression of tumor suppressors induced by this epigenetic mechanism appears to be associated with cancer development. In this review we address the effect of folate on early development and aging through an epigenetic mechanism, DNA methylation. PMID:19733471

  8. DNA methylation, an epigenetic mechanism connecting folate to healthy embryonic development and aging.

    PubMed

    Kim, Kyong-chol; Friso, Simonetta; Choi, Sang-Woon

    2009-12-01

    Experimental studies demonstrated that maternal exposure to certain environmental and dietary factors during early embryonic development can influence the phenotype of offspring as well as the risk of disease development at the later life. DNA methylation, an epigenetic phenomenon, has been suggested as a mechanism by which maternal nutrients affect the phenotype of their offspring in both honeybee and agouti mouse models. Phenotypic changes through DNA methylation can be linked to folate metabolism by the knowledge that folate, a coenzyme of one-carbon metabolism, is directly involved in methyl group transfer for DNA methylation. During the fetal period, organ-specific DNA methylation patterns are established through epigenetic reprogramming. However, established DNA methylation patterns are not immutable and can be modified during our lifetime by the environment. Aberrant changes in DNA methylation with diet may lead to the development of age-associated diseases including cancer. It is also known that the aging process by itself is accompanied by alterations in DNA methylation. Diminished activity of DNA methyltransferases (Dnmts) can be a potential mechanism for the decreased genomic DNA methylation during aging, along with reduced folate intake and altered folate metabolism. Progressive hypermethylation in promoter regions of certain genes is observed throughout aging, and repression of tumor suppressors induced by this epigenetic mechanism appears to be associated with cancer development. In this review, we address the effect of folate on early development and aging through an epigenetic mechanism, DNA methylation.

  9. Derivation of human embryonic stem cells from developing and arrested embryos.

    PubMed

    Zhang, Xin; Stojkovic, Petra; Przyborski, Stefan; Cooke, Michael; Armstrong, Lyle; Lako, Majlinda; Stojkovic, Miodrag

    2006-12-01

    Human embryonic stem cells (hESC) hold huge promise in modern regenerative medicine, drug discovery, and as a model for studying early human development. However, usage of embryos and derivation of hESC for research and potential medical application has resulted in polarized ethical debates since the process involves destruction of viable developing human embryos. Here we describe that not only developing embryos (morulae and blastocysts) of both good and poor quality but also arrested embryos could be used for the derivation of hESC. Analysis of arrested embryos demonstrated that these embryos express pluripotency marker genes such OCT4, NANOG, and REX1. Derived hESC lines also expressed specific pluripotency markers (TRA-1-60, TRA-1-81, SSEA4, alkaline phosphatase, OCT4, NANOG, TERT, and REX1) and differentiated under in vitro and in vivo conditions into derivates of all three germ layers. All of the new lines, including lines derived from late arrested embryos, have normal karyotypes. These results demonstrate that arrested embryos are additional valuable resources to surplus and donated developing embryos and should be used to study early human development or derive pluripotent hESC.

  10. Immunolocalization of myosin Va in the developing nervous system of embryonic chicks.

    PubMed

    Azevedo, Alexandre; Lunardi, Laurelúcia O; Larson, Roy E

    2004-08-01

    Myosins are molecular motors associated with the actin cytoskeleton that participate in the mechanisms of cellular motility. During the development of the nervous system, migration of nerve cells to specific sites, extension of growth cones, and axonal transport are dramatic manifestations of cellular motility. We demonstrate, via immunoblots, the expression of myosin Va during early stages of embryonic development in chicks, extending from the blastocyst period to the beginning of the fetal period. The expression of myosin Va in specific regions and cellular structures of the nervous system during these early stages was determined by immunocytochemistry using a polyclonal antibody. Whole mounts of chick embryos at 24-30-h stages showed intense immunoreactivity of the neural tube in formation along its full extent. Cross-sections at these stages of development showed strong labeling in neuroepithelial cells at the basal and apical regions of the neural tube wall. Embryos at more advanced periods of development (48 h and 72 h) showed distinctive immunolabeling of neuroepithelial cells, neuroblasts and their cytoplasmic extensions in the mantle layer of the stratified neural tube wall, and neuroblasts and their cytoplasmic extensions in the internal wall of the optic cup, as well as a striking labeling of cells in the apparent nuclei of cranial nerves and budding fibers. These immunolocalization studies indicate temporal and site-specific expression of myosin Va during chick embryo development, suggesting that myosin Va expression is related to recruitment for specific cellular tasks.

  11. Signal transduction and transcriptional adaptation in embryonic heart development and during myocardial hypertrophy.

    PubMed

    Ghatpande, S; Goswami, S; Mascareno, E; Siddiqui, M A

    1999-06-01

    In comparing the pathological state of cardiac hypertrophy with early embryonic growth and development of the primitive heart, important and informative aspects of mechanisms that underlie activation of the gene expression pattern become apparent. Interestingly, in both cases the muscle phenotypes share the expression of a 'fetal' gene expression program, raising the question whether the same genetic mechanism is being called upon by signals associated with the onsets of cardiogenesis and myocardial hypertrophy. A cell specific transcription factor, CLP-1, was recently identified in our laboratory that is likely to play a crucial role, in conjunction with other known regulatory factors, in early cardiac events leading to cardiogenic cell specification and differentiation. We have also identified a novel mechanism that involves activation of the Jak/Stat signaling pathway that is linked to the autocrine angiotensin-II loop associated with the hypertrophic response in cardiomyocytes. Since early cardiac cell development and the hypertrophic state involve the expression of the same battery of genes, one may speculate that common transcription factors may account for assembling a competent apparatus responsible for transcribing the genes. Our present studies are designed to investigate the potential role of these factors in control of both processes.

  12. Embryonic development of pleuropodia of the cicada, Magicicada cassini

    PubMed Central

    Strauß, Johannes; Lakes-Harlan, Reinhard

    2006-01-01

    In many insects the first abdominal segment possesses embryonic appendages called pleuropodia. Here we show the embryogenesis of pleuropodial cells of the periodical cicada, Magicicada cassini (Fisher 1851) (Insecta, Homoptera, Cicadidae). An antibody, anti-horseradish perioxidase (HRP), that is usually neuron-specific strongly marked the pleuropodial anlagen and revealed their ectodermal origin shortly after limb bud formation. Thereafter the cells sank into the epidermis and their apical parts enlarged. A globular part protruded from the body wall. Filamentous structures were marked at the stem region and into the apical dilation. In later embryonic stages the pleuropodia degenerated. Despite the binding of anti-HRP the cells had no morphological neuronal characters and cannot be regarded as neurons. The binding indicates that glycosylated cell surface molecules contribute to the adhesion between the presumably glandular pleuropodial cells. In comparison, anti-HRP does not mark the pleuropodia of Orthoptera. PMID:19537987

  13. Embryonic development of pleuropodia of the cicada, Magicicada cassini.

    PubMed

    Strauss, Johannes; Lakes-Harlan, Reinhard

    2006-01-01

    In many insects the first abdominal segment possesses embryonic appendages called pleuropodia. Here we show the embryogenesis of pleuropodial cells of the periodical cicada, Magicicada cassini (Fisher 1851) (Insecta, Homoptera, Cicadidae). An antibody, anti-horseradish perioxidase (HRP), that is usually neuron-specific strongly marked the pleuropodial anlagen and revealed their ectodermal origin shortly after limb bud formation. Thereafter the cells sank into the epidermis and their apical parts enlarged. A globular part protruded from the body wall. Filamentous structures were marked at the stem region and into the apical dilation. In later embryonic stages the pleuropodia degenerated. Despite the binding of anti-HRP the cells had no morphological neuronal characters and cannot be regarded as neurons. The binding indicates that glycosylated cell surface molecules contribute to the adhesion between the presumably glandular pleuropodial cells. In comparison, anti-HRP does not mark the pleuropodia of Orthoptera.

  14. Changes in Laminin Expression Pattern during Early Differentiation of Human Embryonic Stem Cells.

    PubMed

    Pook, Martin; Teino, Indrek; Kallas, Ade; Maimets, Toivo; Ingerpuu, Sulev; Jaks, Viljar

    2015-01-01

    Laminin isoforms laminin-511 and -521 are expressed by human embryonic stem cells (hESC) and can be used as a growth matrix to culture these cells under pluripotent conditions. However, the expression of these laminins during the induction of hESC differentiation has not been studied in detail. Furthermore, the data regarding the expression pattern of laminin chains in differentiating hESC is scarce. In the current study we aimed to fill this gap and investigated the potential changes in laminin expression during early hESC differentiation induced by retinoic acid (RA). We found that laminin-511 but not -521 accumulates in the committed cells during early steps of hESC differentiation. We also performed a comprehensive analysis of the laminin chain repertoire and found that pluripotent hESC express a more diverse range of laminin chains than shown previously. In particular, we provide the evidence that in addition to α1, α5, β1, β2 and γ1 chains, hESC express α2, α3, β3, γ2 and γ3 chain proteins and mRNA. Additionally, we found that a variant of laminin α3 chain-145 kDa-accumulated in RA-treated hESC showing that these cells produce prevalently specifically modified version of α3 chain in early phase of differentiation.

  15. Changes in Laminin Expression Pattern during Early Differentiation of Human Embryonic Stem Cells

    PubMed Central

    Pook, Martin; Teino, Indrek; Kallas, Ade; Maimets, Toivo; Ingerpuu, Sulev; Jaks, Viljar

    2015-01-01

    Laminin isoforms laminin-511 and -521 are expressed by human embryonic stem cells (hESC) and can be used as a growth matrix to culture these cells under pluripotent conditions. However, the expression of these laminins during the induction of hESC differentiation has not been studied in detail. Furthermore, the data regarding the expression pattern of laminin chains in differentiating hESC is scarce. In the current study we aimed to fill this gap and investigated the potential changes in laminin expression during early hESC differentiation induced by retinoic acid (RA). We found that laminin-511 but not -521 accumulates in the committed cells during early steps of hESC differentiation. We also performed a comprehensive analysis of the laminin chain repertoire and found that pluripotent hESC express a more diverse range of laminin chains than shown previously. In particular, we provide the evidence that in addition to α1, α5, β1, β2 and γ1 chains, hESC express α2, α3, β3, γ2 and γ3 chain proteins and mRNA. Additionally, we found that a variant of laminin α3 chain—145 kDa—accumulated in RA-treated hESC showing that these cells produce prevalently specifically modified version of α3 chain in early phase of differentiation. PMID:26378917

  16. Type 1 and 3 inositol trisphosphate receptors are required for extra-embryonic vascular development.

    PubMed

    Uchida, Keiko; Nakazawa, Maki; Yamagishi, Chihiro; Mikoshiba, Katsuhiko; Yamagishi, Hiroyuki

    2016-10-01

    The embryonic-maternal interface of the placental labyrinth, allantois, and yolk sac are vital during embryogenesis; however, the precise mechanism underlying the vascularization of these structures remains unknown. Herein we focus on the role of inositol 1,4,5-trisphosphate (IP3) receptors (IP3R), which are intracellular Ca(2+) release channels, in placentation. Double knockout (DKO) of type 1 and 3 IP3Rs (IP3R1 and IP3R3, respectively) in mice resulted in embryonic lethality around embryonic day (E) 11.5. Because IP3R1 and IP3R3 were co-expressed in endothelial cells in the labyrinth, allantois, and yolk sac, we investigated extra-embryonic vascular development in IP3R1- and IP3R3-DKO mice. The formation of chorionic plates and yolk sac vessels seemed dysregulated around the timing of the chorio-allantoic attachment, immediately followed by the disorganization of allantoic vessels, the decreased expression of the spongiotrophoblast cell marker Tpbpa and the growth retardation of the embryos in DKO mice. Fluorescent immunohistochemistry demonstrated downregulation of a vascular endothelial marker, CD31, in labyrinth embryonic vessels and poor elongation of extra-embryonic mesoderm into the labyrinth layer in DKO placenta, whereas the branching of the DKO chorionic trophoblast was initiated. In addition, allantoic and yolk sac vessels in extra-embryonic tissues were less remodeled in DKO mice. In vitro endothelial cord formation and migration activities of cultured vascular endothelial cells derived from human umbilical vein were downregulated under the inhibition of IP3R. Our results suggest that IP3R1 and IP3R3 are required for extra-embryonic vascularization in the placenta, allantois, and yolk sac. This is the first demonstration of the essential role of IP3/IP3Rs signaling in the development of the vasculature at the embryonic-maternal interface.

  17. Anterograde Tracing Method using DiI to Label Vagal Innervation of the Embryonic and Early Postnatal Mouse Gastrointestinal Tract

    PubMed Central

    Murphy, Michelle C.; Fox, Edward A.

    2007-01-01

    The mouse is an extremely valuable model for studying vagal development in relation to strain differences, genetic variation, gene manipulations, or pharmacological manipulations. Therefore, a method using 1, 1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate (DiI) was developed for labeling vagal innervation of the gastrointestinal (GI) tract in embryonic and postnatal mice. DiI labeling was adapted and optimized for this purpose by varying several facets of the method. For example, insertion and crushing of DiI crystals into the nerve led to faster DiI diffusion along vagal axons and diffusion over longer distances as compared with piercing the nerve with a micropipette tip coated with dried DiI oil. Moreover, inclusion of EDTA in the fixative reduced leakage of DiI out of nerve fibers that occurred with long incubations. Also, mounting labeled tissue in PBS was superior to glycerol with n-propyl gallate, which resulted in reduced clarity of DiI labeling that may have been due to DiI leaking out of fibers. Optical sectioning of flattened wholemounts permitted examination of individual tissue layers of the GI tract wall. This procedure aided identification of nerve ending types because in most instances each type innervates a different tissue layer. Between embryonic day 12.5 and postnatal day 8, growth of axons into the GI tract, formation and patterning of fiber bundles in the myenteric plexus and early formation of putative afferent and efferent nerve terminals were observed. Thus, the DiI tracing method developed here has opened up a window for investigation during an important phase of vagal development. PMID:17418900

  18. Physiology and Endocrinology Symposium: The current status of heat shock in early embryonic survival and reproductive efficiency

    USDA-ARS?s Scientific Manuscript database

    The Physiology and Endocrinology Symposium entitled “The Current Status of Heat Shock in Early Embryonic Survival and Reproductive Efficiency” was held at the Joint ADSA-CSAS-AMPA-WSAS-ASAS Meeting in Phoenix, Arizona, July 15 to 19, 2012. In recent years, data has accumulated suggesting a role for...

  19. Maternal Diabetes Leads to Adaptation in Embryonic Amino Acid Metabolism during Early Pregnancy

    PubMed Central

    Gürke, Jacqueline; Hirche, Frank; Thieme, René; Haucke, Elisa; Schindler, Maria; Stangl, Gabriele I.; Fischer, Bernd; Navarrete Santos, Anne

    2015-01-01

    During pregnancy an adequate amino acid supply is essential for embryo development and fetal growth. We have studied amino acid composition and branched chain amino acid (BCAA) metabolism at day 6 p.c. in diabetic rabbits and blastocysts. In the plasma of diabetic rabbits the concentrations of 12 amino acids were altered in comparison to the controls. Notably, the concentrations of the BCAA leucine, isoleucine and valine were approximately three-fold higher in diabetic rabbits than in the control. In the cavity fluid of blastocysts from diabetic rabbits BCAA concentrations were twice as high as those from controls, indicating a close link between maternal diabetes and embryonic BCAA metabolism. The expression of BCAA oxidizing enzymes and BCAA transporter was analysed in maternal tissues and in blastocysts. The RNA amounts of three oxidizing enzymes, i.e. branched chain aminotransferase 2 (Bcat2), branched chain ketoacid dehydrogenase (Bckdha) and dehydrolipoyl dehydrogenase (Dld), were markedly increased in maternal adipose tissue and decreased in liver and skeletal muscle of diabetic rabbits than in those of controls. Blastocysts of diabetic rabbits revealed a higher Bcat2 mRNA and protein abundance in comparison to control blastocysts. The expression of BCAA transporter LAT1 and LAT2 were unaltered in endometrium of diabetic and healthy rabbits, whereas LAT2 transcripts were increased in blastocysts of diabetic rabbits. In correlation to high embryonic BCAA levels the phosphorylation amount of the nutrient sensor mammalian target of rapamycin (mTOR) was enhanced in blastocysts caused by maternal diabetes. These results demonstrate a direct impact of maternal diabetes on BCAA concentrations and degradation in mammalian blastocysts with influence on embryonic mTOR signalling. PMID:26020623

  20. Maternal Diabetes Leads to Adaptation in Embryonic Amino Acid Metabolism during Early Pregnancy.

    PubMed

    Gürke, Jacqueline; Hirche, Frank; Thieme, René; Haucke, Elisa; Schindler, Maria; Stangl, Gabriele I; Fischer, Bernd; Navarrete Santos, Anne

    2015-01-01

    During pregnancy an adequate amino acid supply is essential for embryo development and fetal growth. We have studied amino acid composition and branched chain amino acid (BCAA) metabolism at day 6 p.c. in diabetic rabbits and blastocysts. In the plasma of diabetic rabbits the concentrations of 12 amino acids were altered in comparison to the controls. Notably, the concentrations of the BCAA leucine, isoleucine and valine were approximately three-fold higher in diabetic rabbits than in the control. In the cavity fluid of blastocysts from diabetic rabbits BCAA concentrations were twice as high as those from controls, indicating a close link between maternal diabetes and embryonic BCAA metabolism. The expression of BCAA oxidizing enzymes and BCAA transporter was analysed in maternal tissues and in blastocysts. The RNA amounts of three oxidizing enzymes, i.e. branched chain aminotransferase 2 (Bcat2), branched chain ketoacid dehydrogenase (Bckdha) and dehydrolipoyl dehydrogenase (Dld), were markedly increased in maternal adipose tissue and decreased in liver and skeletal muscle of diabetic rabbits than in those of controls. Blastocysts of diabetic rabbits revealed a higher Bcat2 mRNA and protein abundance in comparison to control blastocysts. The expression of BCAA transporter LAT1 and LAT2 were unaltered in endometrium of diabetic and healthy rabbits, whereas LAT2 transcripts were increased in blastocysts of diabetic rabbits. In correlation to high embryonic BCAA levels the phosphorylation amount of the nutrient sensor mammalian target of rapamycin (mTOR) was enhanced in blastocysts caused by maternal diabetes. These results demonstrate a direct impact of maternal diabetes on BCAA concentrations and degradation in mammalian blastocysts with influence on embryonic mTOR signalling.

  1. Fibrinogen Stabilizes Placental-Maternal Attachment During Embryonic Development in the Mouse

    PubMed Central

    Iwaki, Takayuki; Sandoval-Cooper, Mayra J.; Paiva, Melissa; Kobayashi, Takao; Ploplis, Victoria A.; Castellino, Francis J.

    2002-01-01

    In humans, maternal fibrinogen (Fg) is required to support pregnancies by maintaining hemostatic balance and stabilizing uteroplacental attachment at the fibrinoid layer found at the fetal-maternal junction. To examine relationships between low Fg levels and early fetal loss, a genetic model of afibrinogenemia was developed. Pregnant mice homozygous for a deletion of the Fg-γ chain, which results in a total Fg deficiency state (FG−/−), aborted the fetuses at the equivalent gestational stage seen in humans. Results obtained from timed matings of FG−/− mice showed that vaginal bleeding was initiated as early as embryonic day (E)6 to 7, a critical stage for maternal-fetal vascular development. The condition of afibrinogenemia retarded embryo-placental development, and consistently led to abortion and maternal death at E9.75. Lack of Fg did not alter the extent or distribution pattern of other putative factors of embryo-placental attachment, including laminin, fibronectin, and Factor XIII, indicating that the presence of fibrin(ogen) is required to confer sufficient stability at the placental-decidual interface. The results of these studies demonstrate that maternal Fg plays a critical role in maintenance of pregnancy in mice, both by supporting proper development of fetal-maternal vascular communication and stabilization of embryo implantation. PMID:11891199

  2. Early tissue patterning recreated by mouse embryonic fibroblasts in a three-dimensional environment.

    PubMed

    Quintana, Lluís; Muiños, Teresa Fernández; Genove, Elsa; Del Mar Olmos, María; Borrós, Salvador; Semino, Carlos E

    2009-01-01

    Cellular self-organization studies have been mainly focused on models such as Volvox, the slime mold Dictyostelium discoideum, and animal (metazoan) embryos. Moreover, animal tissues undergoing regeneration also exhibit properties of embryonic systems such as the self-organization process that rebuilds tissue complexity and function. We speculated that the recreation in vitro of the biological, biophysical, and biomechanical conditions similar to those of a regenerative milieu could elicit the intrinsic capacity of differentiated cells to proceed to the development of a tissue-like structure. Here we show that, when primary mouse embryonic fibroblasts are cultured in a soft nanofiber scaffold, they establish a cellular network that causes an organized cell contraction,proliferation, and migration that ends in the formation of a symmetrically bilateral structure with a distinct central axis. A subset of mesodermal genes (brachyury, Sox9, Runx2) is upregulated during this morphogenetic process. The expression of brachyury was localized first at the central axis, extending then to both sides of the structure. The spontaneous formation of cartilage-like tissue mainly at the paraxial zone followed expression ofSox9 and Runx2. Because cellular self-organization is an intrinsic property of the tissues undergoing development,this model could lead to new ways to consider tissue engineering and regenerative medicine.

  3. Early Tissue Patterning Recreated by Mouse Embryonic Fibroblasts in a Three-Dimensional Environment

    PubMed Central

    Quintana, Lluís; Muiños, Teresa Fernández; Genové, Elsa; Del Mar Olmos, María; Borrós, Salvador

    2009-01-01

    Cellular self-organization studies have been mainly focused on models such as Volvox, the slime mold Dictyostelium discoideum, and animal (metazoan) embryos. Moreover, animal tissues undergoing regeneration also exhibit properties of embryonic systems such as the self-organization process that rebuilds tissue complexity and function. We speculated that the recreation in vitro of the biological, biophysical, and biomechanical conditions similar to those of a regenerative milieu could elicit the intrinsic capacity of differentiated cells to proceed to the development of a tissue-like structure. Here we show that, when primary mouse embryonic fibroblasts are cultured in a soft nanofiber scaffold, they establish a cellular network that causes an organized cell contraction, proliferation, and migration that ends in the formation of a symmetrically bilateral structure with a distinct central axis. A subset of mesodermal genes (brachyury, Sox9, Runx2) is upregulated during this morphogenetic process. The expression of brachyury was localized first at the central axis, extending then to both sides of the structure. The spontaneous formation of cartilage-like tissue mainly at the paraxial zone followed expression of Sox9 and Runx2. Because cellular self-organization is an intrinsic property of the tissues undergoing development, this model could lead to new ways to consider tissue engineering and regenerative medicine. PMID:19025338

  4. Maternal serotonin is crucial for murine embryonic development

    PubMed Central

    Côté, Francine; Fligny, Cécile; Bayard, Elisa; Launay, Jean-Marie; Gershon, Michael D.; Mallet, Jacques; Vodjdani, Guilan

    2007-01-01

    The early appearance of serotonin and its receptors during prenatal development, together with the many effects serotonin exerts during CNS morphogenesis, strongly suggest that serotonin influences the development and maturation of the mammalian brain before it becomes a neuromodulator/neurotransmitter. Sites of early serotonin biosynthesis, however, have not been detected in mouse embryos or extraembryonic structures, suggesting that the main source of serotonin could be of maternal origin. This hypothesis was tested by using knockout mice lacking the tph1 gene, which is responsible for the synthesis of peripheral serotonin. Genetic crosses were performed to compare the phenotype of pups born from homozygous and heterozygous mothers. Observations provide the first clear evidence that (i) maternal serotonin is involved in the control of morphogenesis during developmental stages that precede the appearance of serotonergic neurons and (ii) serotonin is critical for normal murine development. Most strikingly, the phenotype of tph1−/− embryos depends more on the maternal genotype than on that of the concepti. Consideration of the maternal genotype may thus help to clarify the influence of other genes in complex diseases, such as mental illness. PMID:17182745

  5. Analysis of transcription factor Stk40 expression and function during mouse pre-implantation embryonic development.

    PubMed

    Zhang, Junqiang; Zhang, Juanjuan; Zhao, Chun; Shen, Rong; Guo, Xirong; Li, Chaojun; Ling, Xiufeng; Liu, Chang

    2014-02-01

    Determining the molecular mechanisms in the regulation of early embryonic development is crucial for assisted reproductive technology clinical applications. Serine/threonine protein kinase 40 (Stk40) is a member of the serine/threonine kinase family. It is essential in diverse signaling pathways associated with a wide range of cellular activities, including proliferation, differentiation, survival and apoptosis. However, its involvement and molecular mechanisms in pre‑implantation embryonic development have not been well‑defined. In the present study, it was demonstrated that Stk40 was involved in the development of mouse pre‑implantation embryos. Immunofluorescence and confocal microscopy analyses showed that Stk40 was equally expressed in the nuclei and cytoplasm during all stages of pre‑implantation mouse embryos of imprinting control region mice. Reverse transcription‑polymerase chain reaction showed a significantly higher transcription rate of Stk40 mRNA in the two‑cell stage. The results demonstrated that Stk40 downregulation by microinjection of small interfering RNA into the mouse zygote markedly decreased the blastulation compared with that in the control (Stk40i‑1 vs. control: 65.2% and 77.0%, P<0.05 and Stk40i‑2 vs. control: 49.8% and 70.1%, respectively, P<0.05). In addition, silencing of Stk40 significantly increased the transcription rate of reticulocalbin‑2, whereas that of the homeobox protein, Cdx2, was decreased. In conclusion, the results suggested that Stk40 may be critical in the development of pre‑implantation embryos.

  6. Serum levels of acute phase proteins: SAA, Hp and progesterone (P4) in mares with early embryonic death.

    PubMed

    Krakowski, L; Krawczyk, C H; Kostro, K; Stefaniak, T; Novotny, F; Obara, J

    2011-08-01

    The study involved 46 healthy purebred Arabian mares exhibiting regular oestrous cycles that underwent artificial insemination (AI). Pregnancy was detected ultrasonographically (US) in 40 mares. In 15 mares in foal, early embryonic death (EED) was observed during the pregnancy days 14-21. Blood for determinations of serum acute phase proteins (SAA and Hp) and progesterone (P4) was sampled 12-24 h before ovulation and the first insemination, at 12, 24, 72, 96 h and on day 7, 10, 14, 21, 35 and 55 after ovulation. The results revealed that in 25 mares without EED, the serum levels of P4, SAA and Hp were within physiological limits; in 15 mares with EED, the levels of SAA and Hp were significantly increased. In seven mares with EED, high levels of SAA and Hp were already found before ovulation and at 12, 24, 72, 96 h as well as on day 7 and 10 post-ovulation, whereas the level of P4 was normal for early pregnancy. In the remaining eight mares with EED, increased levels of SAA and Hp were found at 72 h after ovulation and maintained until day 55. In this group, the level of P4 decreased since 96 h after ovulation. Determinations of SAA, Hp and P4 in mares in early pregnancy (EP) are useful for monitoring normal development of pregnancy and for diagnosis of subclinical genital inflammations, which may lead to EED. © 2011 Blackwell Verlag GmbH.

  7. Altered Hemodynamics in the Embryonic Heart Affects Outflow Valve Development

    PubMed Central

    Menon, Vinal; Eberth, John F.; Goodwin, Richard L.; Potts, Jay D.

    2016-01-01

    Cardiac valve structure and function are primarily determined during early development. Consequently, abnormally-formed heart valves are the most common type of congenital heart defects. Several adult valve diseases can be backtracked to abnormal valve development, making it imperative to completely understand the process and regulation of heart valve development. Epithelial-to-mesenchymal transition (EMT) plays an important role in the development of heart valves. Though hemodynamics is vital to valve development, its role in regulating EMT is still unknown. In this study, intracardiac hemodynamics were altered by constricting the outflow tract (OFT)/ventricle junction (OVJ) of HH16–17 (Hamilton and Hamburger (HH) Stage 16–17) chicken embryos, ex ovo for 24 h. The constriction created an increase in peak and time-averaged centerline velocity along the OFT without changes to volumetric flow or heart rate. Computational fluid dynamics was used to estimate the level of increased spatially-averaged wall shear stresses on the OFT cushion from AMIRA reconstructions. OFT constriction led to a significant decrease in OFT cushion volume and the number of invaded mesenchyme in the OFT cushion. qPCR analysis revealed altered mRNA expression of a representative panel of genes, vital to valve development, in the OFT cushions from banded hearts. This study indicates the importance of hemodynamics in valve development. PMID:26878022

  8. Effects of dehydration on cardiovascular development in the embryonic American alligator (Alligator mississipiensis).

    PubMed

    Tate, Kevin B; Eme, John; Swart, Justin; Conlon, J Michael; Crossley, Dane A

    2012-07-01

    Effects of dehydration on reptilian embryonic cardiovascular function are unknown. Here, we present the first morphological and physiological data quantifying the cumulative effects of four acute dehydration events on the embryonic American alligator, Alligator mississipiensis. We hypothesized that dehydration would alter embryonic morphology, reduce blood volume and augment the response to angiotensin II (Ang II), a key osmotic and blood volume regulatory response element in adult vertebrates. Drying events at 30%, 40%, 50%, and 60% of embryonic incubation reduced total egg water content by 14.43 ± 0.37 g, a 3.4 fold increase relative to controls. However, embyronic blood volume was greater in the dehydration group at 70% of embryonic incubation compared to controls (0.39 ± 0.044 mLg(-1) and 0.22 ± 0.03 mLg(-1), respectively), however, both groups were similar at 90% of incubation (0.18 ± 0.02 mLg(-1) in the controls and 0.23 ± 0.03 mLg(-1) in the dehydrated group). Dehydration altered the morphological phenotype and resulted in an overall reduction in embryonic mass at both incubation time points measured. Dehydration also altered the physiological phenotype, resulting in embryonic alligators that were relatively bradycardic at 90% of incubation. Arterial Ang II injections resulted in a dose dependent hypertension, which increased in intensity over the span of incubation studied. While progressive incubation altered the Ang II response, dehydration had no impact on the cardiovascular responses to the peptide. Quantification of Ang II type-1 receptor protein using western blot analysis illustrated that dehydration condition and incubation time point did not alter protein quantity. Collectively, our results show that dehydration during embryonic development of the American alligator alters embryonic morphology and baseline heart rate without altering arterial pressure and response to Ang II.

  9. Lipidome signatures in early bovine embryo development.

    PubMed

    Sudano, Mateus J; Rascado, Tatiana D S; Tata, Alessandra; Belaz, Katia R A; Santos, Vanessa G; Valente, Roniele S; Mesquita, Fernando S; Ferreira, Christina R; Araújo, João P; Eberlin, Marcos N; Landim-Alvarenga, Fernanda D C

    2016-07-15

    Mammalian preimplantation embryonic development is a complex, conserved, and well-orchestrated process involving dynamic molecular and structural changes. Understanding membrane lipid profile fluctuation during this crucial period is fundamental to address mechanisms governing embryogenesis. Therefore, the aim of the present work was to perform a comprehensive assessment of stage-specific lipid profiles during early bovine embryonic development and associate with the mRNA abundance of lipid metabolism-related genes (ACSL3, ELOVL5, and ELOVL6) and with