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Sample records for identifies late embryogenesis

  1. A mammary stem cell population identified and characterized in late embryogenesis reveals similarities to human breast cancer.

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    Spike, Benjamin T; Engle, Dannielle D; Lin, Jennifer C; Cheung, Samantha K; La, Justin; Wahl, Geoffrey M

    2012-02-03

    Gene expression signatures relating mammary stem cell populations to breast cancers have focused on adult tissue. Here, we identify, isolate, and characterize the fetal mammary stem cell (fMaSC) state since the invasive and proliferative processes of mammogenesis resemble phases of cancer progression. fMaSC frequency peaks late in embryogenesis, enabling more extensive stem cell purification than achieved with adult tissue. fMaSCs are self-renewing, multipotent, and coexpress multiple mammary lineage markers. Gene expression, transplantation, and in vitro analyses reveal putative autocrine and paracrine regulatory mechanisms, including ErbB and FGF signaling pathways impinging on fMaSC growth. Expression profiles from fMaSCs and associated stroma exhibit significant similarities to basal-like and Her2+ intrinsic breast cancer subtypes. Our results reveal links between development and cancer and provide resources to identify new candidates for diagnosis, prognosis, and therapy.

  2. Late Embryogenesis Abundant Proteins

    NARCIS (Netherlands)

    Shih, M.D.; Hoekstra, F.A.; Hsing, Y.I.C.

    2008-01-01

    During the late maturation stage of seed development, water content decreases greatly. One of the most striking characteristics of mature orthodox seeds is their ability to withstand severe desiccation. Mechanisms of plant drought/desiccation tolerance have been studied by numerous groups, and a bro

  3. Late Embryogenesis Abundant (LEA proteins in legumes

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    Marina eBattaglia

    2013-06-01

    Full Text Available Plants are exposed to different external conditions that affect growth, development, and productivity. Water deficit is one of these adverse conditions caused by drought, salinity, and extreme temperatures. Plants have developed different responses to prevent, ameliorate or repair the damage inflicted by these stressful environments. One of these responses is the activation of a set of genes encoding a group of hydrophilic proteins that typically accumulate to high levels during seed dehydration, at the last stage of embryogenesis, hence named Late Embryogenesis Abundant (LEA proteins. LEA proteins also accumulate in response to water limitation in vegetative tissues, and have been classified in seven groups based on their amino acid sequence similarity and on the presence of distinctive conserved motifs. These proteins are widely distributed in the plant kingdom, from ferns to angiosperms, suggesting a relevant role in the plant response to this unfavorable environmental condition. In this review, we analyzed the LEA proteins from those legumes whose complete genomes have been sequenced such as Phaseolus vulgaris, Glycine max, Medicago truncatula, Lotus japonicus, Cajanus cajan and Cicer arietinum. Considering their distinctive motifs, LEA proteins from the different groups were identified, and their sequence analysis allowed the recognition of novel legume specific motifs. Moreover, we compile their transcript accumulation patterns based on publicly available data. In spite of the limited information on these proteins in legumes, the analysis and data compiled here confirms the high correlation between their accumulation and water deficit, reinforcing their functional relevance under this detrimental conditions.

  4. Overexpression Analysis of emv2 gene coding for Late Embryogenesis Abundant Protein from Vigna radiata (Wilczek

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    Rajesh S.

    2008-10-01

    Full Text Available Late embryogenesis abundant (LEA proteins are speculated to protect against water stress deficit in plants. An over expression system for mungbean late embryogenesis abundant protein, emv2 was constructed in a pET29a vector, designated pET-emv2 which is responsible for higher expression under the transcriptional/translational control of T7/lac promoter incorporated in the Escherichia coli BL21 (DE3.Induction protocol was optimized for pET recombinants harboring the target gene. Overexpressed EMV2 protein was purified to homogeneity and the protein profile monitored by SDS-PAGE.

  5. Overexpression of Late Embryogenesis Abundant 14 enhances Arabidopsis salt stress tolerance

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    Jia, Fengjuan, E-mail: jfj.5566@163.com; Qi, Shengdong, E-mail: zisexanwu@163.com; Li, Hui, E-mail: 332453593@qq.com; Liu, Pu, E-mail: banbaokezhan@163.com; Li, Pengcheng, E-mail: lpcsdau@163.com; Wu, Changai, E-mail: cawu@sdau.edu.cn; Zheng, Chengchao, E-mail: cczheng@sdau.edu.cn; Huang, Jinguang, E-mail: jghuang@sdau.edu.cn

    2014-11-28

    Highlights: • It is the first time to investigate the biological function of AtLEA14 in salt stress response. • AtLEA14 enhances the salt stress tolerance both in Arabidopsis and yeast. • AtLEA14 responses to salt stress by stabilizing AtPP2-B11, an E3 ligase, under normal or salt stress conditions. - Abstract: Late embryogenesis abundant (LEA) proteins are implicated in various abiotic stresses in higher plants. In this study, we identified a LEA protein from Arabidopsis thaliana, AtLEA14, which was ubiquitously expressed in different tissues and remarkably induced with increased duration of salt treatment. Subcellular distribution analysis demonstrated that AtLEA14 was mainly localized in the cytoplasm. Transgenic Arabidopsis and yeast overexpressing AtLEA14 all exhibited enhanced tolerance to high salinity. The transcripts of salt stress-responsive marker genes (COR15a, KIN1, RD29B and ERD10) were overactivated in AtLEA14 overexpressing lines compared with those in wild type plants under normal or salt stress conditions. In vivo and in vitro analysis showed that AtLEA14 could effectively stabilize AtPP2-B11, an important E3 ligase. These results suggested that AtLEA14 had important protective functions under salt stress conditions in Arabidopsis.

  6. Expression in Escherichia coli of Three Different Soybean Late Embryogenesis Abundant (LEA) Genes to Investigate Enhanced Stress Tolerance

    Institute of Scientific and Technical Information of China (English)

    Ying LAN; Dan CAI; Yi-Zhi ZHENG

    2005-01-01

    In order to identify the function of late embryogenesis abundant (LEA) genes, in vitro functional analyses were perfo rmed using an Escherichia coli heterologous expression system. Three soybean late embryogenesis abundant (LEA) genes, PM11 (GenBank accession No. AF004805; group 1), PM30 (AF1 17884; group 3), and ZLDE-2 (AY351918; group 2), were cloned and expressed in a pET-28a system.The gene products were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and identified by mass spectrometry. E. coli cells containing the recombinant plasmids or empty vector as controls were treated by salt and low temperature stress. Compared with control cells, the E. coli cells expressing either PM11 or PM30 showed a shorter lag period and improved growth when transferred to LB (Luria-Bertani) liquid media containing 800 mmol/L NaCl or 700 mmol/L KCl or after 4 ℃ treatment. E. coli cells expressing ZLDE-2 did not show obvious growth improvement both in either high KCl medium or after 4 ℃ treatment. The results indicate that the E. coli expression system is a simple, useful method to identify the functions of some stress-tolerant genes from plants.

  7. Effect of High Thermal Manipulations during Early and Late Embryogenesis on Asymmetry for Broilers

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    Sezai Alkan

    2015-11-01

    Full Text Available The aim of this study was to determine the effect of thermal manipulations during early and late embryogenesis on asymmetry in terms of sides of shank length, shank width and face length of broilers. Incubation conditions were 37.5°C and 55% relative humidity for control group throughout the incubation period until the 19th days. In the thermally treated eggs during early embryogenesis (8-10 days, incubation temperature was increased to 41°C and relative humidity to 65% for 3 hours (12.00-15.00 on the 8th-10th days of incubation. Also, in the late embryogenesis stage (16-18 days incubation temperature was increased to 41°C and relative humidity to 65 % for 3 hours (12.00-15.00 on the 16th-18th days of incubation. Total 16 chickens were selected at randomly from all experimental groups to determine the asymmetry. The weekly left and right sides of shank length, shank width and face length of chickens were measured from 7 days of age to 35 days of age, and relative asymmetry values were calculated. There was no significant difference among the groups in point of relative asymmetry. Asymmetry values were reduced due to aging.

  8. LEA (Late Embryogenesis Abundant proteins and their encoding genes in Arabidopsis thaliana

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    Hincha Dirk K

    2008-03-01

    Full Text Available Abstract Background LEA (late embryogenesis abundant proteins have first been described about 25 years ago as accumulating late in plant seed development. They were later found in vegetative plant tissues following environmental stress and also in desiccation tolerant bacteria and invertebrates. Although they are widely assumed to play crucial roles in cellular dehydration tolerance, their physiological and biochemical functions are largely unknown. Results We present a genome-wide analysis of LEA proteins and their encoding genes in Arabidopsis thaliana. We identified 51 LEA protein encoding genes in the Arabidopsis genome that could be classified into nine distinct groups. Expression studies were performed on all genes at different developmental stages, in different plant organs and under different stress and hormone treatments using quantitative RT-PCR. We found evidence of expression for all 51 genes. There was only little overlap between genes expressed in vegetative tissues and in seeds and expression levels were generally higher in seeds. Most genes encoding LEA proteins had abscisic acid response (ABRE and/or low temperature response (LTRE elements in their promoters and many genes containing the respective promoter elements were induced by abscisic acid, cold or drought. We also found that 33% of all Arabidopsis LEA protein encoding genes are arranged in tandem repeats and that 43% are part of homeologous pairs. The majority of LEA proteins were predicted to be highly hydrophilic and natively unstructured, but some were predicted to be folded. Conclusion The analyses indicate a wide range of sequence diversity, intracellular localizations, and expression patterns. The high fraction of retained duplicate genes and the inferred functional diversification indicate that they confer an evolutionary advantage for an organism under varying stressful environmental conditions. This comprehensive analysis will be an important starting point for

  9. Functional insights into the late embryogenesis abundant (LEA) protein family from Dendrobium officinale (Orchidaceae) using an Escherichia coli system.

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    Ling, Hong; Zeng, Xu; Guo, Shunxing

    2016-12-22

    Late embryogenesis abundant (LEA) proteins, a diverse family, accumulate during seed desiccation in the later stages of embryogenesis. LEA proteins are associated with tolerance to abiotic stresses, such as drought, salinity and high or cold temperature. Here, we report the first comprehensive survey of the LEA gene family in Dendrobium officinale, an important and widely grown medicinal orchid in China. Based on phylogenetic relationships with the complete set of Arabidopsis and Oryza LEA proteins, 17 genes encoding D. officinale LEAs (DofLEAs) were identified and their deduced proteins were classified into seven groups. The motif composition of these deduced proteins was correlated with the gene structure found in each LEA group. Our results reveal the DofLEA genes are widely distributed and expressed in tissues. Additionally, 11 genes from different groups were introduced into Escherichia coli to assess the functions of DofLEAs. Expression of 6 and 7 DofLEAs in E. coli improved growth performance compared with the control under salt and heat stress, respectively. Based on qPCR data, all of these genes were up-regulated in various tissues following exposure to salt and heat stresses. Our results suggest that DofLEAs play an important role in responses to abiotic stress.

  10. A novel chemical screening strategy in zebrafish identifies common pathways in embryogenesis and rhabdomyosarcoma development.

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    Le, Xiuning; Pugach, Emily K; Hettmer, Simone; Storer, Narie Y; Liu, Jianing; Wills, Airon A; DiBiase, Antony; Chen, Eleanor Y; Ignatius, Myron S; Poss, Kenneth D; Wagers, Amy J; Langenau, David M; Zon, Leonard I

    2013-06-01

    The zebrafish is a powerful genetic model that has only recently been used to dissect developmental pathways involved in oncogenesis. We hypothesized that operative pathways during embryogenesis would also be used for oncogenesis. In an effort to define RAS target genes during embryogenesis, gene expression was evaluated in Tg(hsp70-HRAS(G12V)) zebrafish embryos subjected to heat shock. dusp6 was activated by RAS, and this was used as the basis for a chemical genetic screen to identify small molecules that interfere with RAS signaling during embryogenesis. A KRAS(G12D)-induced zebrafish embryonal rhabdomyosarcoma was then used to assess the therapeutic effects of the small molecules. Two of these inhibitors, PD98059 and TPCK, had anti-tumor activity as single agents in both zebrafish embryonal rhabdomyosarcoma and a human cell line of rhabdomyosarcoma that harbored activated mutations in NRAS. PD98059 inhibited MEK1 whereas TPCK suppressed S6K1 activity; however, the combined treatment completely suppressed eIF4B phosphorylation and decreased translation initiation. Our work demonstrates that the activated pathways in RAS induction during embryogenesis are also important in oncogenesis and that inhibition of these pathways suppresses tumor growth.

  11. [Functions of late embryogenesis abundant proteins in desiccation-tolerance of organisms: a review].

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    Liu, Yun; Liu, Guobao; Li, Ranhui; Zou, Yongdong; Zheng, Yizhi

    2010-05-01

    Late embryogenesis abundant (LEA) proteins are well associated with the desiccation tolerance in organisms. LEA proteins are categorized into at least seven groups by virtue of similarities in their deduced amino acid sequences. Most of the LEA proteins have the characteristics of high hydrophilicity and thermo-stability. The LEA proteins are in unstructured conformation in aqueous solution. However, they adopted amphiphilic alpha-helix structure during desiccation condition. LEA proteins are localized to the different organelles in the cells, i.e. cytoplasm, endoplasmic reticulum, mitochondria and nucleus. The multi-functional capacity of LEA proteins are suggested, as protein stabilization, protection of enzyme activity, membrane association and stabilization, antioxidant function, metal-ion binding or DNA protection, etc. Here, we review the structural and functional characteristics of LEA proteins to provide a reference platform to understand their protective mechanisms during the adaptive response to desiccation in organisms.

  12. Late embryogenesis abundant proteins protect human hepatoma cells during acute desiccation.

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    Li, Shumin; Chakraborty, Nilay; Borcar, Apurva; Menze, Michael A; Toner, Mehmet; Hand, Steven C

    2012-12-18

    Expression of late embryogenesis abundant (LEA) proteins is highly correlated with desiccation tolerance in anhydrobiotic animals, selected land plants, and bacteria. Genes encoding two LEA proteins, one localized to the cytoplasm/nucleus (AfrLEA2) and one targeted to mitochondria (AfrLEA3m), were stably transfected into human HepG2 cells. A trehalose transporter was used for intracellular loading of this disaccharide. Cells were rapidly and uniformly desiccated to low water content (spin-drying technique. Immediately on rehydration, control cells without LEA proteins or trehalose exhibited 0% membrane integrity, compared with 98% in cells loaded with trehalose and expressing AfrLEA2 or AfrLEA3m; surprisingly, AfrLEA3m without trehalose conferred 94% protection. Cell proliferation across 7 d showed an 18-fold increase for cells dried with AfrLEA3m and trehalose, compared with 27-fold for nondried controls. LEA proteins dramatically enhance desiccation tolerance in mammalian cells and offer the opportunity for engineering biostability in the dried state.

  13. Visualizing late insect embryogenesis: extraembryonic and mesodermal enhancer trap expression in the beetle Tribolium castaneum.

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    Stefan Koelzer

    Full Text Available The beetle Tribolium castaneum has increasingly become a powerful model for comparative research on insect development. One recent resource is a collection of piggyBac transposon-based enhancer trap lines. Here, we provide a detailed analysis of three selected lines and demonstrate their value for investigations in the second half of embryogenesis, which has thus far lagged behind research on early stages. Two lines, G12424 and KT650, show enhanced green fluorescent protein (EGFP expression throughout the extraembryonic serosal tissue and in a few discrete embryonic domains. Intriguingly, both lines show for the first time a degree of regionalization within the mature serosa. However, their expression profiles illuminate distinct aspects of serosal biology: G12424 tracks the tissue's rapid maturation while KT650 expression likely reflects ongoing physiological processes. The third line, G04609, is stably expressed in mesodermal domains, including segmental muscles and the heart. Genomic mapping followed by in situ hybridization for genes near to the G04609 insertion site suggests that the transposon has trapped enhancer information for the Tribolium orthologue of midline (Tc-mid. Altogether, our analyses provide the first live imaging, long-term characterizations of enhancer traps from this collection. We show that EGFP expression is readily detected, including in heterozygote crosses that permit the simultaneous visualization of multiple tissue types. The tissue specificity provides live, endogenous marker gene expression at key developmental stages that are inaccessible for whole mount staining. Furthermore, the nonlocalized EGFP in these lines illuminates both the nucleus and cytoplasm, providing cellular resolution for morphogenesis research on processes such as dorsal closure and heart formation. In future work, identification of regulatory regions driving these enhancer traps will deepen our understanding of late developmental control

  14. Visualizing late insect embryogenesis: extraembryonic and mesodermal enhancer trap expression in the beetle Tribolium castaneum.

    Science.gov (United States)

    Koelzer, Stefan; Kölsch, Yvonne; Panfilio, Kristen A

    2014-01-01

    The beetle Tribolium castaneum has increasingly become a powerful model for comparative research on insect development. One recent resource is a collection of piggyBac transposon-based enhancer trap lines. Here, we provide a detailed analysis of three selected lines and demonstrate their value for investigations in the second half of embryogenesis, which has thus far lagged behind research on early stages. Two lines, G12424 and KT650, show enhanced green fluorescent protein (EGFP) expression throughout the extraembryonic serosal tissue and in a few discrete embryonic domains. Intriguingly, both lines show for the first time a degree of regionalization within the mature serosa. However, their expression profiles illuminate distinct aspects of serosal biology: G12424 tracks the tissue's rapid maturation while KT650 expression likely reflects ongoing physiological processes. The third line, G04609, is stably expressed in mesodermal domains, including segmental muscles and the heart. Genomic mapping followed by in situ hybridization for genes near to the G04609 insertion site suggests that the transposon has trapped enhancer information for the Tribolium orthologue of midline (Tc-mid). Altogether, our analyses provide the first live imaging, long-term characterizations of enhancer traps from this collection. We show that EGFP expression is readily detected, including in heterozygote crosses that permit the simultaneous visualization of multiple tissue types. The tissue specificity provides live, endogenous marker gene expression at key developmental stages that are inaccessible for whole mount staining. Furthermore, the nonlocalized EGFP in these lines illuminates both the nucleus and cytoplasm, providing cellular resolution for morphogenesis research on processes such as dorsal closure and heart formation. In future work, identification of regulatory regions driving these enhancer traps will deepen our understanding of late developmental control, including in the

  15. Oil palm (Elaeis guineensis Jacq.) tissue culture ESTs: Identifying genes associated with callogenesis and embryogenesis

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    Low, Eng-Ti L; Alias, Halimah; Boon, Soo-Heong; Shariff, Elyana M; Tan, Chi-Yee A; Ooi, Leslie CL; Cheah, Suan-Choo; Raha, Abdul-Rahim; Wan, Kiew-Lian; Singh, Rajinder

    2008-01-01

    Background Oil palm (Elaeis guineensis Jacq.) is one of the most important oil bearing crops in the world. However, genetic improvement of oil palm through conventional breeding is extremely slow and costly, as the breeding cycle can take up to 10 years. This has brought about interest in vegetative propagation of oil palm. Since the introduction of oil palm tissue culture in the 1970s, clonal propagation has proven to be useful, not only in producing uniform planting materials, but also in the development of the genetic engineering programme. Despite considerable progress in improving the tissue culture techniques, the callusing and embryogenesis rates from proliferating callus cultures remain very low. Thus, understanding the gene diversity and expression profiles in oil palm tissue culture is critical in increasing the efficiency of these processes. Results A total of 12 standard cDNA libraries, representing three main developmental stages in oil palm tissue culture, were generated in this study. Random sequencing of clones from these cDNA libraries generated 17,599 expressed sequence tags (ESTs). The ESTs were analysed, annotated and assembled to generate 9,584 putative unigenes distributed in 3,268 consensi and 6,316 singletons. These unigenes were assigned putative functions based on similarity and gene ontology annotations. Cluster analysis, which surveyed the relatedness of each library based on the abundance of ESTs in each consensus, revealed that lipid transfer proteins were highly expressed in embryogenic tissues. A glutathione S-transferase was found to be highly expressed in non-embryogenic callus. Further analysis of the unigenes identified 648 non-redundant simple sequence repeats and 211 putative full-length open reading frames. Conclusion This study has provided an overview of genes expressed during oil palm tissue culture. Candidate genes with expression that are modulated during tissue culture were identified. However, in order to confirm

  16. Oil palm (Elaeis guineensis Jacq. tissue culture ESTs: Identifying genes associated with callogenesis and embryogenesis

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    Ooi Leslie CL

    2008-05-01

    Full Text Available Abstract Background Oil palm (Elaeis guineensis Jacq. is one of the most important oil bearing crops in the world. However, genetic improvement of oil palm through conventional breeding is extremely slow and costly, as the breeding cycle can take up to 10 years. This has brought about interest in vegetative propagation of oil palm. Since the introduction of oil palm tissue culture in the 1970s, clonal propagation has proven to be useful, not only in producing uniform planting materials, but also in the development of the genetic engineering programme. Despite considerable progress in improving the tissue culture techniques, the callusing and embryogenesis rates from proliferating callus cultures remain very low. Thus, understanding the gene diversity and expression profiles in oil palm tissue culture is critical in increasing the efficiency of these processes. Results A total of 12 standard cDNA libraries, representing three main developmental stages in oil palm tissue culture, were generated in this study. Random sequencing of clones from these cDNA libraries generated 17,599 expressed sequence tags (ESTs. The ESTs were analysed, annotated and assembled to generate 9,584 putative unigenes distributed in 3,268 consensi and 6,316 singletons. These unigenes were assigned putative functions based on similarity and gene ontology annotations. Cluster analysis, which surveyed the relatedness of each library based on the abundance of ESTs in each consensus, revealed that lipid transfer proteins were highly expressed in embryogenic tissues. A glutathione S-transferase was found to be highly expressed in non-embryogenic callus. Further analysis of the unigenes identified 648 non-redundant simple sequence repeats and 211 putative full-length open reading frames. Conclusion This study has provided an overview of genes expressed during oil palm tissue culture. Candidate genes with expression that are modulated during tissue culture were identified. However

  17. Characterization of a group 1 late embryogenesis abundant protein in encysted embryos of the brine shrimp Artemia franciscana.

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    Sharon, Michelle A; Kozarova, Anna; Clegg, James S; Vacratsis, Panayiotis O; Warner, Alden H

    2009-04-01

    Late embryogenesis abundant (LEA) proteins are hydrophilic molecules that are believed to function in desiccation and low-temperature tolerance in some plants and plant propagules, certain prokaryotes, and several animal species. The brine shrimp Artemia franciscana can produce encysted embryos (cysts) that enter diapause and are resistant to severe desiccation. This ability is based on biochemical adaptations, one of which appears to be the accumulation of the LEA protein that is the focus of this study. The studies described herein characterize a 21 kDa protein in encysted Artemia embryos as a group 1 LEA protein. The amino acid sequence of this protein and its gene have been determined and entered into the NCBI database (no. EF656614). The LEA protein consists of 182 amino acids and it is extremely hydrophilic, with glycine (23%), glutamine (17%), and glutamic acid (12.6%) being the most abundant amino acids. This protein also consists of 8 tandem repeats of a 20 amino acid sequence, which is characteristic of group 1 LEA proteins from non-animal species. The LEA protein and its gene are expressed only in encysted embryos and not in larvae or adults. Evidence is presented to show that the LEA protein functions in the prevention of drying-induced protein aggregation, which supports its functional role in desiccation tolerance. This report describes, for the first time, the purification and characterization of a group 1 LEA protein from an animal species.

  18. Conformation of a group 2 late embryogenesis abundant protein from soybean. Evidence of poly (L-proline)-type II structure.

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    Soulages, Jose L; Kim, Kangmin; Arrese, Estela L; Walters, Christina; Cushman, John C

    2003-03-01

    Late embryogenesis abundant (LEA) proteins are members of a large group of hydrophilic, glycine-rich proteins found in plants, algae, fungi, and bacteria known collectively as hydrophilins that are preferentially expressed in response to dehydration or hyperosmotic stress. Group 2 LEA (dehydrins or responsive to abscisic acid) proteins are postulated to stabilize macromolecules against damage by freezing, dehydration, ionic, or osmotic stress. However, the structural and physicochemical properties of group 2 LEA proteins that account for such functions remain unknown. We have analyzed the structural properties of a recombinant form of a soybean (Glycine max) group 2 LEA (rGmDHN1). Differential scanning calorimetry of purified rGmDHN1 demonstrated that the protein does not display a cooperative unfolding transition upon heating. Ultraviolet absorption and circular dichroism spectroscopy revealed that the protein is in a largely hydrated and unstructured conformation in solution. However, ultraviolet absorption and circular dichroism measurements collected at different temperatures showed that the protein exists in equilibrium between two extended conformational states: unordered and left-handed extended helical or poly (L-proline)-type II structures. It is estimated that 27% of the residues of rGmDHN1 adopt or poly (L-proline)-type II-like helical conformation at 12 degrees C. The content of extended helix gradually decreases to 15% as the temperature is increased to 80 degrees C. Studies of the conformation of the protein in solution in the presence of liposomes, trifluoroethanol, and sodium dodecyl sulfate indicated that rGmDHN1 has a very low intrinsic ability to adopt alpha-helical structure and to interact with phospholipid bilayers through amphipathic alpha-helices. The ability of the protein to remain in a highly extended conformation at low temperatures could constitute the basis of the functional role of GmDHN1 in the prevention of freezing, desiccation

  19. Group 3 late embryogenesis abundant proteins from embryos of Artemia franciscana: structural properties and protective abilities during desiccation.

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    Boswell, Leaf C; Menze, Michael A; Hand, Steven C

    2014-01-01

    Group 3 late embryogenesis abundant (LEA) proteins are highly hydrophilic, and their expression is associated with desiccation tolerance in both plants and animals. Here we show that two LEA proteins from embryos of Artemia franciscana, AfrLEA2 and AfrLEA3m, are intrinsically disordered in solution but upon desiccation gain secondary structure, as measured by circular dichroism. Trifluoroethanol and sodium dodecyl sulfate are both shown to induce α-helical structure in AfrLEA2 and AfrLEA3m. Bioinformatic predictions of secondary-structure content for both proteins correspond most closely to conformations measured in the dry state. Because some LEA proteins afford protection to desiccation-sensitive proteins during drying and subsequent rehydration, we tested for this capacity in AfrLEA2 and AfrLEA3m. The protective capacities vary, depending on the target enzyme. For the cytoplasmic enzyme lactate dehydrogenase, neither AfrLEA2 nor AfrLEA3m, with or without trehalose present, was able to afford protection better than that provided by bovine serum albumin (BSA) under the same conditions. However, for another cytoplasmic enzyme, phosphofructokinase, both AfrLEA2 and AfrLEA3m in the presence of trehalose were able to afford protection far greater than that provided by BSA with trehalose. Finally, for the mitochondrial enzyme citrate synthase, 400-μg/mL AfrLEA3m without trehalose provided significantly more protection than the same concentration of either AfrLEA2 or BSA.

  20. Study of model systems to test the potential function of Artemia group 1 late embryogenesis abundant (LEA) proteins.

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    Warner, Alden H; Guo, Zhi-hao; Moshi, Sandra; Hudson, John W; Kozarova, Anna

    2016-01-01

    Embryos of the brine shrimp, Artemia franciscana, are genetically programmed to develop either ovoviparously or oviparously depending on environmental conditions. Shortly upon their release from the female, oviparous embryos enter diapause during which time they undergo major metabolic rate depression while simultaneously synthesize proteins that permit them to tolerate a wide range of stressful environmental events including prolonged periods of desiccation, freezing, and anoxia. Among the known stress-related proteins that accumulate in embryos entering diapause are the late embryogenesis abundant (LEA) proteins. This large group of intrinsically disordered proteins has been proposed to act as molecular shields or chaperones of macromolecules which are otherwise intolerant to harsh conditions associated with diapause. In this research, we used two model systems to study the potential function of the group 1 LEA proteins from Artemia. Expression of the Artemia group 1 gene (AfrLEA-1) in Escherichia coli inhibited growth in proportion to the number of 20-mer amino acid motifs expressed. As well, clones of E. coli, transformed with the AfrLEA-1 gene, expressed multiple bands of LEA proteins, either intrinsically or upon induction with isopropyl-β-thiogalactoside (IPTG), in a vector-specific manner. Expression of AfrLEA-1 in E. coli did not overcome the inhibitory effects of high concentrations of NaCl and KCl but modulated growth inhibition resulting from high concentrations of sorbitol in the growth medium. In contrast, expression of the AfrLEA-1 gene in Saccharomyces cerevisiae did not alter the growth kinetics or permit yeast to tolerate high concentrations of NaCl, KCl, or sorbitol. However, expression of AfrLEA-1 in yeast improved its tolerance to drying (desiccation) and freezing. Under our experimental conditions, both E. coli and S. cerevisiae appear to be potentially suitable hosts to study the function of Artemia group 1 LEA proteins under environmentally

  1. Late Embryogenesis Abundant (LEA Constitutes a Large and Diverse Family of Proteins Involved in Development and Abiotic Stress Responses in Sweet Orange (Citrus sinensis L. Osb..

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    Andresa Muniz Pedrosa

    Full Text Available Late Embryogenesis Abundant (LEA proteins are an ubiquitous group of polypeptides that were first described to accumulate during plant seed dehydration, at the later stages of embryogenesis. Since then they have also been recorded in vegetative plant tissues experiencing water limitation and in anhydrobiotic bacteria and invertebrates and, thereby, correlated with the acquisition of desiccation tolerance. This study provides the first comprehensive study about the LEA gene family in sweet orange (Citrus sinensis L. Osb., the most important and widely grown fruit crop around the world. A surprisingly high number (72 of genes encoding C. sinensis LEAs (CsLEAs were identified and classified into seven groups (LEA_1, LEA_2, LEA_3 and LEA_4, LEA_5, DEHYDRIN and SMP based on their predicted amino acid sequences and also on their phylogenetic relationships with the complete set of Arabidopsis thaliana LEA proteins (AtLEAs. Approximately 60% of the CsLEAs identified in this study belongs to the unusual LEA_2 group of more hydrophobic LEA proteins, while the other LEA groups contained a relatively small number of members typically hydrophilic. A correlation between gene structure and motif composition was observed within each LEA group. Investigation of their chromosomal localizations revealed that the CsLEAs were non-randomly distributed across all nine chromosomes and that 33% of all CsLEAs are segmentally or tandemly duplicated genes. Analysis of the upstream sequences required for transcription revealed the presence of various stress-responsive cis-acting regulatory elements in the promoter regions of CsLEAs, including ABRE, DRE/CRT, MYBS and LTRE. Expression analysis using both RNA-seq data and quantitative real-time RT-PCR (qPCR revealed that the CsLEA genes are widely expressed in various tissues, and that many genes containing the ABRE promoter sequence are induced by drought, salt and PEG. These results provide a useful reference for further

  2. Transcriptome Profiling Identifies Ribosome Biogenesis as a Target of Alcohol Teratogenicity and Vulnerability during Early Embryogenesis

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    Berres, Mark E.; Garic, Ana; Flentke, George R.; Smith, Susan M.

    2017-01-01

    Fetal alcohol spectrum disorder (FASD) is a leading cause of neurodevelopmental disability. Individuals with FASD may exhibit a characteristic facial appearance that has diagnostic utility. The mechanism by which alcohol disrupts craniofacial development is incompletely understood, as are the genetic factors that can modify individual alcohol vulnerability. Using an established avian model, we characterized the cranial transcriptome in response to alcohol to inform the mechanism underlying these cells’ vulnerability. Gallus gallus embryos having 3–6 somites were exposed to 52 mM alcohol and the cranial transcriptomes were sequenced thereafter. A total of 3422 genes had significantly differential expression. The KEGG pathways with the greatest enrichment of differentially expressed gene clusters were Ribosome (P = 1.2 x 10−17, 67 genes), Oxidative Phosphorylation (P = 4.8 x 10−12, 60 genes), RNA Polymerase (P = 2.2 x 10−3, 15 genes) and Spliceosome (P = 2.6 x 10−2, 39 genes). The preponderance of transcripts in these pathways were repressed in response to alcohol. These same gene clusters also had the greatest altered representation in our previous comparison of neural crest populations having differential vulnerability to alcohol-induced apoptosis. Comparison of differentially expressed genes in alcohol-exposed (3422) and untreated, alcohol-vulnerable (1201) transcriptomes identified 525 overlapping genes of which 257 have the same direction of transcriptional change. These included 36 ribosomal, 25 oxidative phosphorylation and 7 spliceosome genes. Using a functional approach in zebrafish, partial knockdown of ribosomal proteins zrpl11, zrpl5a, and zrps3a individually heightened vulnerability to alcohol-induced craniofacial deficits and increased apoptosis. In humans, haploinsufficiency of several of the identified ribosomal proteins are causative in craniofacial dysmorphologies such as Treacher Collins Syndrome and Diamond-Blackfan Anemia. This work

  3. Expression Profiles of 12 Late Embryogenesis Abundant Protein Genes from Tamarix hispida in Response to Abiotic Stress

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    Caiqiu Gao

    2014-01-01

    Full Text Available Twelve embryogenesis abundant protein (LEA genes (named ThLEA-1 to -12 were cloned from Tamarix hispida. The expression profiles of these genes in response to NaCl, PEG, and abscisic acid (ABA in roots, stems, and leaves of T. hispida were assessed using real-time reverse transcriptase-polymerase chain reaction (RT-PCR. These ThLEAs all showed tissue-specific expression patterns in roots, stems, and leaves under normal growth conditions. However, they shared a high similar expression patterns in the roots, stems, and leaves when exposed to NaCl and PEG stress. Furthermore, ThLEA-1, -2, -3, -4, and -11 were induced by NaCl and PEG, but ThLEA-5, -6, -8, -10, and -12 were downregulated by salt and drought stresses. Under ABA treatment, some ThLEA genes, such as ThLEA-1, -2, and -3, were only slightly differentially expressed in roots, stems, and leaves, indicating that they may be involved in the ABA-independent signaling pathway. These findings provide a basis for the elucidation of the function of LEA genes in future work.

  4. Molecular cloning and characterization of the late embryogenesis abundant group 4 (EgLEA4 gene from oil palm (Elaeis guineensis Jacq

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    Watcharasuda Hualkasin

    2013-06-01

    Full Text Available The Late-Embryogenesis Abundant group 4 (LEA4 genes is a group of genes that have been reported to be involved in stress and hormone responses. The completed LEA4 cDNA sequence was first obtained from a set of EST sequences of oil palm (Elaeis guineensis Jacq, named as EgLEA4. The open reading frame is 486 bp in length, encoding a deduced amino acid sequence of 161 residues with a molecular weight of 16.5 kDa and a pI value of about 8.0. Five amino acid motif patterns were found in the EgLEA4 (II, I, III, IV and V and each had a close identity to similar LEA4 patterns of soybean (64%.Comparison of the nucleotide sequences of the cDNA and the genomic DNA demonstrated that the EgLEA4 gene is composed of 2 exons and 1 intron. The 52 untranslated region shows a putative promoter sequence involved in the transcription process, drought stress and hormone responsive elements. RT-PCR analysis showed that the EgLEA4 gene was only expressed in mesocarp, during the late stages of fruit development. It also had a higher expression in induced drought conditions indicating that the EgLEA4 protein may be involved in plant adaptation and stress (drought responsive pathway.

  5. Sonic Hedgehog modulates EGFR dependent proliferation of neural stem cells during late mouse embryogenesis through EGFR transactivation

    Science.gov (United States)

    Reinchisi, Gisela; Parada, Margarita; Lois, Pablo; Oyanadel, Claudia; Shaughnessy, Ronan; Gonzalez, Alfonso; Palma, Verónica

    2013-01-01

    Sonic Hedgehog (Shh/GLI) and EGFR signaling pathways modulate Neural Stem Cell (NSC) proliferation. How these signals cooperate is therefore critical for understanding normal brain development and function. Here we report a novel acute effect of Shh signaling on EGFR function. We show that during late neocortex development, Shh mediates the activation of the ERK1/2 signaling pathway in Radial Glial cells (RGC) through EGFR transactivation. This process is dependent on metalloprotease activity and accounts for almost 50% of the EGFR-dependent mitogenic response of late NSCs. Furthermore, in HeLa cancer cells, a well-known model for studying the EGFR receptor function, Shh also induces cell proliferation involving EGFR activation, as reflected by EGFR internalization and ERK1/2 phosphorylation. These findings may have important implications for understanding the mechanisms that regulate NSC proliferation during neurogenesis and may lead to novel approaches to the treatment of tumors. PMID:24133411

  6. CpLEA5, the Late Embryogenesis Abundant Protein Gene from Chimonanthus praecox, Possesses Low Temperature and Osmotic Resistances in Prokaryote and Eukaryotes

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    Yiling Liu

    2015-11-01

    Full Text Available Plants synthesize and accumulate a series of stress-resistance proteins to protect normal physiological activities under adverse conditions. Chimonanthus praecox which blooms in freezing weather accumulates late embryogenesis abundant proteins (LEAs in flowers, but C. praecox LEAs are little reported. Here, we report a group of five LEA genes of C. praecox (CpLEA5, KT727031. Prokaryotic-expressed CpLEA5 was employed in Escherichia coli to investigate bioactivities and membrane permeability at low-temperature. In comparison with the vacant strains, CpLEA5-containing strains survived in a 20% higher rate; and the degree of cell membrane damage in CpLEA5-containing strains was 55% of that of the vacant strains according to a conductivity test, revealing the low-temperature resistance of CpLEA5 in bacteria. CpLEA5 was also expressed in Pichia pastoris. Interestingly, besides low-temperature resistance, CpLEA5 conferred high resistance to salt and alkali in CpLEA5 overexpressing yeast. The CpLEA5 gene was transferred into Arabidopsis thaliana to also demonstrate CpLEA5 actions in plants. As expected, the transgenic lines were more resistant against low-temperature and drought while compared with the wild type. Taken together, CpLEA5-conferred resistances to several conditions in prokaryote and eukaryotes could have great value as a genetic technology to enhance osmotic stress and low-temperature tolerance.

  7. Computational and statistical analyses of amino acid usage and physico-chemical properties of the twelve late embryogenesis abundant protein classes.

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    Emmanuel Jaspard

    Full Text Available Late Embryogenesis Abundant Proteins (LEAPs are ubiquitous proteins expected to play major roles in desiccation tolerance. Little is known about their structure - function relationships because of the scarcity of 3-D structures for LEAPs. The previous building of LEAPdb, a database dedicated to LEAPs from plants and other organisms, led to the classification of 710 LEAPs into 12 non-overlapping classes with distinct properties. Using this resource, numerous physico-chemical properties of LEAPs and amino acid usage by LEAPs have been computed and statistically analyzed, revealing distinctive features for each class. This unprecedented analysis allowed a rigorous characterization of the 12 LEAP classes, which differed also in multiple structural and physico-chemical features. Although most LEAPs can be predicted as intrinsically disordered proteins, the analysis indicates that LEAP class 7 (PF03168 and probably LEAP class 11 (PF04927 are natively folded proteins. This study thus provides a detailed description of the structural properties of this protein family opening the path toward further LEAP structure - function analysis. Finally, since each LEAP class can be clearly characterized by a unique set of physico-chemical properties, this will allow development of software to predict proteins as LEAPs.

  8. A late embryogenesis abundant protein HVA1 regulated by an inducible promoter enhances root growth and abiotic stress tolerance in rice without yield penalty.

    Science.gov (United States)

    Chen, Yi-Shih; Lo, Shuen-Fang; Sun, Peng-Kai; Lu, Chung-An; Ho, Tuan-Hua D; Yu, Su-May

    2015-01-01

    Regulation of root architecture is essential for maintaining plant growth under adverse environment. A synthetic abscisic acid (ABA)/stress-inducible promoter was designed to control the expression of a late embryogenesis abundant protein (HVA1) in transgenic rice. The background of HVA1 is low but highly inducible by ABA, salt, dehydration and cold. HVA1 was highly accumulated in root apical meristem (RAM) and lateral root primordia (LRP) after ABA/stress treatments, leading to enhanced root system expansion. Water-use efficiency (WUE) and biomass also increased in transgenic rice, likely due to the maintenance of normal cell functions and metabolic activities conferred by HVA1 which is capable of stabilizing proteins, under osmotic stress. HVA1 promotes lateral root (LR) initiation, elongation and emergence and primary root (PR) elongation via an auxin-dependent process, particularly by intensifying asymmetrical accumulation of auxin in LRP founder cells and RAM, even under ABA/stress-suppressive conditions. We demonstrate a successful application of an inducible promoter in regulating the spatial and temporal expression of HVA1 for improving root architecture and multiple stress tolerance without yield penalty.

  9. Identifying and Investigating the Late-1960s Interhemispheric SST Shift

    Science.gov (United States)

    Friedman, A. R.; Lee, S. Y.; Liu, Y.; Chiang, J. C. H.

    2014-12-01

    The global north-south interhemispheric sea surface temperature (SST) difference experienced a pronounced and rapid decrease in the late 1960s, which has been linked to drying in the Sahel, South Asia, and East Asia. However, some basic questions about the interhemispheric SST shift remain unresolved, including its scale and whether the constituent changes in different basins were coordinated. In this study, we systematically investigate the spatial and temporal behavior of the late-1960s interhemispheric SST shift using ocean surface and subsurface observations. We also evaluate potential mechanisms using control and specific-forcing CMIP5 simulations. Using a regime shift detection technique, we identify the late-1960s shift as the most prominent in the historical observational SST record. We additionally examine the corresponding changes in upper-ocean heat content and salinity associated with the shift. We find that there were coordinated upper-ocean cooling and freshening in the subpolar North Atlantic, the region of the largest-magnitude SST decrease during the interhemispheric shift. These upper-ocean changes correspond to a weakened North Atlantic thermohaline circulation (THC). However, the THC decrease does not fully account for the rapid global interhemispheric SST shift, particularly the warming in the extratropical Southern Hemisphere.

  10. Proteomic analysis reveals differential accumulation of small heat shock proteins and late embryogenesis abundant proteins between ABA-deficient mutant vp5 seeds and wild-type Vp5 seeds in maize

    Directory of Open Access Journals (Sweden)

    Xiaolin eWu

    2015-01-01

    Full Text Available ABA is a major plant hormone that plays important roles during many phases of plant life cycle, including seed development, maturity and dormancy, and especially the acquisition of desiccation tolerance. Understanding of the molecular basis of ABA-mediated plant response to stress is of interest not only in basic research on plant adaptation but also in applied research on plant productivity. Maize mutant viviparous-5 (vp5, deficient in ABA biosynthesis in seeds, is a useful material for studying ABA-mediated response in maize. Due to carotenoid deficiency, vp5 endosperm is white, compared to yellow Vp5 endosperm. However, the background difference at proteome level between vp5 and Vp5 seeds is unclear. This study aimed to characterize proteome alterations of maize vp5 seeds and to identify ABA-dependent proteins during seed maturation. We compared the embryo and endosperm proteomes of vp5 and Vp5 seeds by gel-based proteomics. Up to 46 protein spots, most in embryos, were found to be differentially accumulated between vp5 and Vp5. The identified proteins included small heat shock proteins (sHSPs, late embryogenesis abundant (LEA proteins, stress proteins, storage proteins and enzymes among others. However, EMB564, the most abundant LEA protein in maize embryo, accumulated in comparable levels between vp5 and Vp5 embryos, which contrasted to previously characterized, greatly lowered expression of emb564 mRNA in vp5 embryos. Moreover, LEA proteins and sHSPs displayed differential accumulations in vp5 embryos: six out of eight identified LEA proteins decreased while nine sHSPs increased in abundance. Finally, we discussed the possible causes of global proteome alterations, especially the observed differential accumulation of identified LEA proteins and sHSPs in vp5 embryos. The data derived from this study provides new insight into ABA-dependent proteins and ABA-mediated response during maize seed maturation.

  11. KvLEA, a New Isolated Late Embryogenesis Abundant Protein Gene from Kosteletzkya virginica Responding to Multiabiotic Stresses.

    Science.gov (United States)

    Tang, Xiaoli; Wang, Hongyan; Chu, Liye; Shao, Hongbo

    2016-01-01

    The LEA proteins are a kind of hydrophilic proteins, playing main functions in desiccation tolerance. However, their importance as a kind of stress proteins in abiotic stress is being clarified little by little. In this study we isolated, cloned, and identified the first KvLEA gene in Kosteletzkya virginica. Bioinformatic analysis showed that the protein encoded by this gene had common properties of LEA proteins and the multiple sequences alignment and phylogenetic analysis further showed that this protein had high homology with two Arabidopsis LEA proteins. Gene expression analysis revealed that this gene had a higher expression in root and it was induced obviously by salt stress. Moreover, the transcripts of KvLEA were also induced by other abiotic stresses including drought, high temperature, chilling, and ABA treatment. Among these abiotic stresses, ABA treatment brought about the biggest changes to this gene. Collectively, our research discovered a novel LEA gene and uncovered its involvement in multiabiotic stresses in K. virginica. This research not only enriched studies on LEA gene in plant but also would accelerate more studies on K. virginica in the future.

  12. KvLEA, a New Isolated Late Embryogenesis Abundant Protein Gene from Kosteletzkya virginica Responding to Multiabiotic Stresses

    Directory of Open Access Journals (Sweden)

    Xiaoli Tang

    2016-01-01

    Full Text Available The LEA proteins are a kind of hydrophilic proteins, playing main functions in desiccation tolerance. However, their importance as a kind of stress proteins in abiotic stress is being clarified little by little. In this study we isolated, cloned, and identified the first KvLEA gene in Kosteletzkya virginica. Bioinformatic analysis showed that the protein encoded by this gene had common properties of LEA proteins and the multiple sequences alignment and phylogenetic analysis further showed that this protein had high homology with two Arabidopsis LEA proteins. Gene expression analysis revealed that this gene had a higher expression in root and it was induced obviously by salt stress. Moreover, the transcripts of KvLEA were also induced by other abiotic stresses including drought, high temperature, chilling, and ABA treatment. Among these abiotic stresses, ABA treatment brought about the biggest changes to this gene. Collectively, our research discovered a novel LEA gene and uncovered its involvement in multiabiotic stresses in K. virginica. This research not only enriched studies on LEA gene in plant but also would accelerate more studies on K. virginica in the future.

  13. Cloning and Characterization of a Novel cDNA Encoding Late Embryogenesis-Abundant Protein 5 Like (LEA-5) Gene from Cara Cara Navel Orange Fruit(Citrus sinensis Osbeck)

    Institute of Scientific and Technical Information of China (English)

    TAO Neng-guo; YE Jun-li; XU Juan; DENG Xiu-xin

    2006-01-01

    LEA5 gene was postulated related with both stress and hormone responses. In an attempt to find genes exclusively expressed during fruit ripening of Cara Cara navel orange, a novel cDNA clone encoding late embryogenesis-abundant protein 5 like gene (CitLEA5-1) was obtained. It was 582 bp in length, containing 97 deduced amino acids. Compared with the stress-induced LEA5 from leaves of Citrus sinensis, CitLEA5-1 had a shorter 3' untranslated region (UTR). Semiquantitative RT-PCR analysis revealed that CitLEA5-1 was transcriptional regulated during fruit ripening of Cara Cara navel orange.

  14. Heterologous Expression of MeLEA3: A 10 kDa Late Embryogenesis Abundant Protein of Cassava, Confers Tolerance to Abiotic Stress in Escherichia coli with Recombinant Protein Showing In Vitro Chaperone Activity.

    Science.gov (United States)

    Barros, Nicolle L F; da Silva, Diehgo T; Marques, Deyvid N; de Brito, Fabiano M; dos Reis, Savio P; de Souza, Claudia R B

    2015-01-01

    Late embryogenesis abundant (LEA) proteins are small molecular weight proteins involved in acquisition of tolerance to drought, salinity, high temperature, cold, and freezing stress in many plants. Previous studies revealed a cDNA sequence coding for a 10 kDa atypical LEA protein, named MeLEA3, predicted to be located into mitochondria with potential role in salt stress response of cassava (Manihot esculenta Crantz). Here we aimed to produce the recombinant MeLEA3 protein by heterologous expression in Escherichia coli and evaluate the tolerance of bacteria expressing this protein under abiotic stress. Our result revealed that the recombinant MeLEA3 protein conferred a protective function against heat and salt stress in bacterial cells. Also, the recombinant MeLEA3 protein showed in vitro chaperone activity by protection of NdeI restriction enzyme activity under heat stress.

  15. Variation in transcript abundance during somatic embryogenesis in gymnosperms.

    Science.gov (United States)

    Stasolla, Claudio; Bozhkov, Peter V; Chu, Tzu-Ming; Van Zyl, Leonel; Egertsdotter, Ulrika; Suarez, Maria F; Craig, Deborah; Wolfinger, Russ D; Von Arnold, Sara; Sederoff, Ronald R

    2004-10-01

    Somatic embryogenesis of Norway spruce (Picea abies L.) is a versatile model system to study molecular mechanisms regulating embryo development because it proceeds through defined developmental stages corresponding to specific culture treatments. Normal embryonic development involves early differentiation of proembryogenic masses (PEMs) into somatic embryos, followed by early and late embryogeny leading to the formation of mature cotyledonary embryos. In some cell lines there is a developmental arrest at the PEM-somatic embryo transition. To learn more about the molecular mechanisms regulating embryogenesis, we compared the transcript profiles of two normal lines and one developmentally arrested line. Ribonucleic acid, extracted from these cell lines at successive developmental stages, was analyzed on DNA microarrays containing 2178 expressed sequence tags (ESTs) (corresponding to 2110 unique cDNAs) from loblolly pine (Pinus taeda L.). Hybridization between spruce and pine species on microarrays has been shown to be effective (van Zyl et al. 2002, Stasolla et al. 2003). In contrast to the developmentally arrested line, the early phases of normal embryo development are characterized by a precise pattern of gene expression, i.e., repression followed by induction. Comparison of transcript levels between successive stages of embryogenesis allowed us to identify several genes that showed unique expression responses during normal development. Several of these genes encode proteins involved in detoxification processes, methionine synthesis and utilization, and carbohydrate metabolism. The potential role of these genes in embryo development is discussed.

  16. Retinoid signalling during embryogenesis

    NARCIS (Netherlands)

    Pijnappel, W.W.M.; Hendriks, H.F.J.; Durston, A.J.

    1996-01-01

    Conclusion: Retinoids are suspected to have multiple functions during embryogenesis, which are carried out via various different signal transduction pathways involving active retinoids and nuclear retinoid receptors. Research focuses on the identification of the retinoid signal transduction componen

  17. Embryogenesis in Oak species. A review

    Directory of Open Access Journals (Sweden)

    Aranzazu Gomez-Garay

    2014-08-01

    Full Text Available Aim of study: A review on the propagation methods of four Quercus species, namely Q. suber, Q. robur, Q. ilex and Q. canariensis, through somatic embryogenesis and anther embryogenesis are presented.Area of study: The study comprises both Mediterranean and Atlantic oak species located in Spain.Material and Methods: Somatic embryogenesis was induced on immature zygotic embryos of diverse oak species, permitting the multiplication of half-sib families. Induction of haploid embryos and doubled haploids was assayed in both Q. suber and Q. ilex by temperature stress treatments of anthers containing late vacuolated microspores. The haploid origin of the anther embryos has been evaluated by quantitative nuclear DNA analysis through flow cytometry and by DNA microsatellite markers. Genetic transformation of cork oak has also been performed by means of Agrobacterium tumefaciens vectors. Proteomic analysis has been conducted to screen the diverse protein profiles followed by in vitro derived embryos during their development.Research highlights: Successful plant regeneration from both somatic and haploid embryos has been achieved. In the particular case of cork oak, doubled-haploid plants were obtained. Plantlets regenerated from selected parent trees through somatic embryogenesis were acclimated in the greenhouse and in the nursery, and were planted in an experimental plot in the field. Preliminary evaluation of the cork quality of the plants showed a good heritability correlation with the parent trees. This article revises the work of and is dedicated to Dr. M.A. Bueno, who devoted much of her professional life to the research on Biotechnology and Genetics of forest species, leading the Laboratory of Forest Biotechnology at the Spanish Institute of Agronomic Research (INIA.Key words: anther embryogenesis; microspore; pollen; Quercus canariensis; Quercus ilex; Quercus robur; Quercus suber; somatic embryogenesis

  18. Proteome Analysis Unravels Mechanism Underling the Embryogenesis of the Honeybee Drone and Its Divergence with the Worker (Apis mellifera lingustica).

    Science.gov (United States)

    Fang, Yu; Feng, Mao; Han, Bin; Qi, Yuping; Hu, Han; Fan, Pei; Huo, Xinmei; Meng, Lifeng; Li, Jianke

    2015-09-04

    The worker and drone bees each contain a separate diploid and haploid genetic makeup, respectively. Mechanisms regulating the embryogenesis of the drone and its mechanistic difference with the worker are still poorly understood. The proteomes of the two embryos at three time-points throughout development were analyzed by applying mass spectrometry-based proteomics. We identified 2788 and 2840 proteins in the worker and drone embryos, respectively. The age-dependent proteome driving the drone embryogenesis generally follows the worker's. The two embryos however evolve a distinct proteome setting to prime their respective embryogenesis. The strongly expressed proteins and pathways related to transcriptional-translational machinery and morphogenesis at 24 h drone embryo relative to the worker, illustrating the earlier occurrence of morphogenesis in the drone than worker. These morphogenesis differences remain through to the middle-late stage in the two embryos. The two embryos employ distinct antioxidant mechanisms coinciding with the temporal-difference organogenesis. The drone embryo's strongly expressed cytoskeletal proteins signify key roles to match its large body size. The RNAi induced knockdown of the ribosomal protein offers evidence for the functional investigation of gene regulating of honeybee embryogenesis. The data significantly expand novel regulatory mechanisms governing the embryogenesis, which is potentially important for honeybee and other insects.

  19. Embryogenesis of chordee.

    Science.gov (United States)

    Kaplan, G W; Lamm, D L

    1975-11-01

    Gross and microscopic examination of 46 consecutive male therapeutic abortion specimens, ranging in size from 60 to 180 mm. crown-rump, demonstrated that 89 per cent of the fetuses had some ventral curvature of the penis. Athough presumably all penises are ventrally curved through the tenth week of gestation, in our study this curvature was most prominent in the sixteenth through twentieth weeks of gestation and in 44 per cent of the fetuses it persisted through the sixth lunar month. Examination of premature infants revealed a 31 per cent incidence of chordee and serial examinations of a 27-week gestational age infant demonstrated gradual complete correction of the chordee during the ensuing 6 weeks. We propose that ventral curvature of the penis is a normal stage of embryogenesis and chordee without hypospadias may represent an arrest of development at this earlier stage.

  20. Identifying barriers to HIV testing: personal and contextual factors associated with late HIV testing.

    Science.gov (United States)

    Schwarcz, Sandra; Richards, T Anne; Frank, Heidi; Wenzel, Conrad; Hsu, Ling Chin; Chin, Chi-Sheng Jennie; Murphy, Jessie; Dilley, James

    2011-07-01

    Late diagnosis of HIV is associated with increased morbidity, mortality, and health care costs. Despite the availability of HIV testing, persons continue to test late in the course of HIV infection. We used the HIV/AIDS case registry of San Francisco Department of Public Health to identify and recruit 41 persons who developed AIDS within 12 months of their HIV diagnosis to participate in a qualitative and quantitative interview regarding late diagnosis of HIV. Thirty-one of the participants were diagnosed with HIV because of symptomatic disease and 50% of the participants were diagnosed with HIV and AIDS concurrently. Half of the subjects had not been tested for HIV prior to diagnosis. Fear was the most frequently cited barrier to testing. Other barriers included being unaware of improved HIV treatment, free/low cost care, and risk for HIV. Recommendations for health care providers to increase early diagnosis of HIV include routine ascertainment of HIV risk behaviors and testing histories, stronger recommendations for patients to be tested, and incorporating testing into routine medical care. Public health messages to increase testing include publicizing that (1) effective, tolerable, and low cost/free care for HIV is readily available, (2) early diagnosis of HIV improves health outcomes, (3) HIV can be transmitted to persons who engage in unprotected oral and insertive anal sex and unprotected receptive anal intercourse without ejaculation and from HIV-infected persons whose infection is well-controlled with antiretroviral therapy, (4) persons who may be infected based upon these behaviors should be tested following exposure, (5) HIV testing information will be kept private, and (6) encouraging friends and family to get HIV tested is beneficial.

  1. Adrenomedullin in mammalian embryogenesis.

    Science.gov (United States)

    Garayoa, Mercedes; Bodegas, Elena; Cuttitta, Frank; Montuenga, Luis M

    2002-04-01

    Here are summarized data supporting that adrenomedullin (AM) is a multifunctional factor involved in the complex regulatory mechanisms of mammalian development. During rodent embryogenesis, AM is first expressed in the heart, followed by a broader but also defined spatio-temporal pattern of expression in vascular, neural, and skeletal-forming tissues as well as in the main embryonic internal organs. AM pattern of expression is suggestive of its involvement in the control of embryonic invasion, proliferation, and differentiation processes, probably through autocrine or paracrine modes of action. AM levels in fetoplacental tissues, uterus, maternal and umbilical plasma are highly increased during normal gestation. These findings in addition to other physiological and gene targeting studies support the importance of AM as a vasorelaxant factor implicated in the regulation of maternal vascular adaptation to pregnancy, as well as of fetal and fetoplacental circulations. AM is also present in amniotic fluid and milk, which is suggestive of additional functions in the maturation and immunological protection of the fetus. Altered expression of AM has been found in some gestational pathologies, although it is not yet clear whether this corresponds to causative or compensatory mechanisms. Future studies in regard to the distribution and expression levels of the molecules known to function as AM receptors, together with data on the action of complement factor H (an AM binding protein), may help to better define the roles of AM during embryonic development.

  2. Identifying Risk Factors for Late-Onset (50+) Alcohol Use Disorder and Heavy Drinking

    DEFF Research Database (Denmark)

    Emiliussen, Jakob; Nielsen, Anette Søgaard; Andersen, Kjeld

    2017-01-01

    This systematic review seeks to expand the description and understanding of late-onset AUD and asks “Which risk factors have been reported for late-onset heavy drinking and AUD?” Method: Using PRISMA guidelines, a literature review and search was performed on May 19, 2015 using the following...... with an increased risk for late-onsetAUDor heavy drinking,whereas retirement, death of a spouse or a close relative does not increase the risk. Discussion: Inherent differences in measurements and methodologies precluded a meta-analysis. Therefore, the results presented here are descriptive in nature. Most studies...... possibly has led to misrepresentations and preconceptions on the complex nature of late-onset AUD. There is limited evidence for any specific risk factor for late-onset AUD or heavy drinking. We suggest the adoption of a qualitative approach to uncover what is intrinsic to late-onset AUD followed...

  3. Systematic identification of long noncoding RNAs expressed during zebrafish embryogenesis

    DEFF Research Database (Denmark)

    Pauli, Andrea; Valen, Eivind; Lin, Michael F.;

    2012-01-01

    vertebrate embryogenesis has been elusive. To identify lncRNAs with potential functions in vertebrate embryogenesis, we performed a time series of RNA-Seq experiments at eight stages during early zebrafish development. We reconstructed 56,535 high-confidence transcripts in 28,912 loci, recovering the vast...... overlapping lncRNAs, and precursors for small RNAs (sRNAs). Zebrafish lncRNAs share many of the characteristics of their mammalian counterparts: relatively short length, low exon number, low expression, and conservation levels comparable to introns. Subsets of lncRNAs carry chromatin signatures characteristic...

  4. Gankyrin expression during mouse embryogenesis

    Institute of Scientific and Technical Information of China (English)

    秦建民; 刘淑琴; 曾锦章; 李慎菁; 付晓勇; 邱秀华; 吴孟超; 王红阳

    2004-01-01

    Objective: To observe the gene expression of Gankyrin during mouse embryogenesis and reveal the gene biological significance during organs and tissues formation. Methods: The expressions of Gankyrin mRNA in various organs and tissues were detected by in situ hybridization at indicated times during embryogenesis. Results: The expression of Gankyrin mRNA in mouse day 12.5 embryo was mainly in midbrain, interbrain and endbrain; in mouse day 14.5 embryo mainly in midbrain, aorta, liver, gonad, cranium and rib; in mouse day 16.5 embryo mainly in cranium, rib and vertebra;and in mouse day 18.5 embryo mainly in cranium, rib and intestinal mucosa. Conclusion: Gankyrin gene probably participates in the development of the neural tissues (such as midbrain, interbrain and endbrain etc. ), aorta, liver and gonad, intestinal mucosa and bone tissues, which may be closely associated with the function of the organs and tissues.

  5. "Why is Toma Late to School Again?" Preschoolers Identify the Most Informative Questions

    Science.gov (United States)

    Ruggeri, Azzurra

    2017-01-01

    The current study investigates whether preschoolers are able to successfully identify the most effective among given questions, adapting their reliance on different types of questions ("constraint-seeking" vs. "hypothesis-scanning") based on the quantitative measure of "expected information gain." Children were…

  6. α1-Syntrophin Variant Identified in Drug-Induced Long QT Syndrome Increases Late Sodium Current.

    Science.gov (United States)

    Choi, Jong-Il; Wang, Chaojian; Thomas, Matthew J; Pitt, Geoffrey S

    2016-01-01

    Drug-induced long-QT syndrome (diLQTS) is often due to drug block of IKr, especially in genetically susceptible patients with subclinical mutations in the IKr-encoding KCHN2. Few variants in the cardiac NaV1.5 Na+ channel complex have been associated with diLQTS. We tested whether a novel SNTA1 (α1-syntrophin) variant (p.E409Q) found in a patient with diLQTS increases late sodium current (INa-L), thereby providing a disease mechanism. Electrophysiological studies were performed in HEK293T cells co-expressing human NaV1.5/nNOS/PMCA4b with either wild type (WT) or SNTA1 variants (A390V-previously reported in congenital LQTS; and E409Q); and in adult rat ventricular cardiomyocytes infected with SNTA1 expressing adenoviruses (WT or one of the two SNTA1 variants). In HEK293T cells and in cardiomyocytes, there was no significant difference in the peak INa densities among the SNTA1 WT and variants. However, both variants increased INa-L (% of peak current) in HEK293T cells (0.58 ± 0.10 in WT vs. 0.90 ± 0.11 in A390V, p = 0.048; vs. 0.88 ± 0.07 in E409Q, p = 0.023). In cardiomyocytes, INa-L was significantly increased by E409Q, but not by A390V compared to WT (0.49 ± 0.14 in WT vs.0.94 ± 0.23 in A390V, p = 0.099; vs. 1.12 ± 0.24 in E409Q, p = 0.019). We demonstrated that a novel SNTA1 variant is likely causative for diLQTS by augmenting INa-L. These data suggest that variants within the NaV1.5-interacting α1-syntrophin are a potential mechanism for diLQTS, thereby expanding the concept that variants within congenital LQTS loci can cause diLQTS.

  7. α1-Syntrophin Variant Identified in Drug-Induced Long QT Syndrome Increases Late Sodium Current.

    Directory of Open Access Journals (Sweden)

    Jong-Il Choi

    Full Text Available Drug-induced long-QT syndrome (diLQTS is often due to drug block of IKr, especially in genetically susceptible patients with subclinical mutations in the IKr-encoding KCHN2. Few variants in the cardiac NaV1.5 Na+ channel complex have been associated with diLQTS. We tested whether a novel SNTA1 (α1-syntrophin variant (p.E409Q found in a patient with diLQTS increases late sodium current (INa-L, thereby providing a disease mechanism. Electrophysiological studies were performed in HEK293T cells co-expressing human NaV1.5/nNOS/PMCA4b with either wild type (WT or SNTA1 variants (A390V-previously reported in congenital LQTS; and E409Q; and in adult rat ventricular cardiomyocytes infected with SNTA1 expressing adenoviruses (WT or one of the two SNTA1 variants. In HEK293T cells and in cardiomyocytes, there was no significant difference in the peak INa densities among the SNTA1 WT and variants. However, both variants increased INa-L (% of peak current in HEK293T cells (0.58 ± 0.10 in WT vs. 0.90 ± 0.11 in A390V, p = 0.048; vs. 0.88 ± 0.07 in E409Q, p = 0.023. In cardiomyocytes, INa-L was significantly increased by E409Q, but not by A390V compared to WT (0.49 ± 0.14 in WT vs.0.94 ± 0.23 in A390V, p = 0.099; vs. 1.12 ± 0.24 in E409Q, p = 0.019. We demonstrated that a novel SNTA1 variant is likely causative for diLQTS by augmenting INa-L. These data suggest that variants within the NaV1.5-interacting α1-syntrophin are a potential mechanism for diLQTS, thereby expanding the concept that variants within congenital LQTS loci can cause diLQTS.

  8. Genome-wide analysis of spatiotemporal gene expression patterns during early embryogenesis in rice.

    Science.gov (United States)

    Itoh, Jun-Ichi; Sato, Yutaka; Sato, Yutaka; Hibara, Ken-Ichiro; Shimizu-Sato, Sae; Kobayashi, Hiromi; Takehisa, Hinako; Sanguinet, Karen A; Namiki, Nobukazu; Nagamura, Yoshiaki

    2016-04-01

    Embryogenesis in rice is different from that of most dicotolydonous plants in that it shows a non-stereotypic cell division pattern, formation of dorsal-ventral polarity, and endogenous initiation of the radicle. To reveal the transcriptional features associated with developmental events during rice early embryogenesis, we used microarray analysis coupled with laser microdissection to obtain both spatial and temporal transcription profiles. Our results allowed us to determine spatial expression foci for each expressed gene in the globular embryo, which revealed the importance of phytohormone-related genes and a suite of transcription factors to early embryogenesis. Our analysis showed the polarized expression of a small number of genes along the apical-basal and dorsal-ventral axes in the globular embryo, which tended to fluctuate in later developmental stages. We also analyzed gene expression patterns in the early globular embryo and how this relates to expression in embryonic organs at later stages. We confirmed the accuracy of the expression patterns found by microarray analysis of embryo subdomains using in situ hybridization. Our study identified homologous genes from Arabidopsis thaliana with known functions in embryogenesis in addition to unique and uncharacterized genes that show polarized expression patterns during embryogenesis. The results of this study are presented in a database to provide a framework for spatiotemporal gene expression during rice embryogenesis, to serve as a resource for future functional analysis of genes, and as a basis for comparative studies of plant embryogenesis.

  9. Periodontal disease in a Portuguese identified skeletal sample from the late nineteenth and early twentieth centuries.

    Science.gov (United States)

    Wasterlain, Sofia N; Cunha, Eugénia; Hillson, Simon

    2011-05-01

    Periodontal status was investigated in 600 adult dentitions belonging to the identified osteological collections curated at the University of Coimbra, Portugal. These collections date to a point temporally intermediate between the large epidemiological studies of the 20th century and archaeological collections that antedate the 19th century. The aim of this study is to compare periodontal data derived from contemporary samples with statistics compiled from epidemiological studies to determine if factors such as age-at-death, sex, and tooth type are essential or not to account for in future archaeological studies of periodontitis. Periodontal disease status was assessed based on the textural and architectural variations of the interdental septum and the extent of bone loss. Overall, the frequency of periodontitis within the Coimbra collections is 73.8%. Men were more susceptible to periodontal disease than women. Gingivitis was widespread in the younger age groups. Destructive periodontitis was observed early in adulthood, rising steadily with age. The most susceptible sites to periodontal breakdown were located in the posterior region of the upper jaw. Some variation in reported frequencies of periodontitis was found in epidemiological reports, which might result from variation in methods for identifying the pathology, differences in the age composition of the samples examined, variation in oral hygiene and/or diet, or some other factors. Regarding the pattern of distribution of periodontal disease, Coimbra results were similar to comparable modern epidemiological surveys, making clear the importance of considering sex, age, and oral distribution of periodontitis in future archaeological studies.

  10. Identifying the annual signal in laminated clastic sediments from a Late Pleistocene lake succession

    Science.gov (United States)

    Barrett, Samuel; Starnberger, Reinhard; Spötl, Christoph; Brauer, Achim; Dulski, Peter

    2014-05-01

    A thick (>250m) succession of laminated lacustrine sediments at the Baumkirchen site in the Inn Valley (Austria) indicates the presence of a lake or series of lake phases existing during Marine Isotope Stage 3. The laminations are highly complex, entirely clastic, and vary considerably in thickness and internal structure. Despite high sedimentation rates of 5-6 cm per year indicated by radiocarbon and pollen data, there is no systematic macroscopic annual pattern in the laminations which could be used to develop a high-resolution (varve) chronology. Microscopic investigations of thin sections revealed sub-mm to cm-scale silt layers punctuated by very thin (0.25-2 mm) clay-rich layers spaced semi-regularly between 2 and 8 cm where present. The spacing and small grain size of these thin layers suggests a possible annual process responsible for their formation: rain-out of the fine suspended sediment from the water column during winter, when fluvial discharge into the lake was negligible and its surface was frozen. These potentially annual layers are not reliably identifiable macroscopically, however, analysis of X-ray fluorescence core scan data revealed the layers to be enriched in several heavy metals: most strongly in Zn but also in Pb, Cu and Ni. Possible carrier minerals of these heavy metals are currently being investigated. The radiocarbon chronology (in the short upper section where it is available) and heavy metal peak counting agree within error suggesting the heavy metal enriched clay-rich layers are mostly annual. Available X-ray fluorescence data for 150 m of the section suggest no significant long-term changes in annual layer spacing (i.e. sedimentation rate) from the 5-6 cm average indicated by the radiocarbon data, although there is a high degree of small-scale variation. Preliminary optically stimulated luminescence dates point to the presence of several hiatuses in this succession suggesting a fragmented record containing several lake periods of

  11. Systematic analysis of pleiotropy in C. elegans early embryogenesis.

    Directory of Open Access Journals (Sweden)

    Lihua Zou

    2008-02-01

    Full Text Available Pleiotropy refers to the phenomenon in which a single gene controls several distinct, and seemingly unrelated, phenotypic effects. We use C. elegans early embryogenesis as a model to conduct systematic studies of pleiotropy. We analyze high-throughput RNA interference (RNAi data from C. elegans and identify "phenotypic signatures", which are sets of cellular defects indicative of certain biological functions. By matching phenotypic profiles to our identified signatures, we assign genes with complex phenotypic profiles to multiple functional classes. Overall, we observe that pleiotropy occurs extensively among genes involved in early embryogenesis, and a small proportion of these genes are highly pleiotropic. We hypothesize that genes involved in early embryogenesis are organized into partially overlapping functional modules, and that pleiotropic genes represent "connectors" between these modules. In support of this hypothesis, we find that highly pleiotropic genes tend to reside in central positions in protein-protein interaction networks, suggesting that pleiotropic genes act as connecting points between different protein complexes or pathways.

  12. Meta-analysis of Genome Wide Association Studies Identifies Genetic Markers of Late Toxicity Following Radiotherapy for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Sarah L. Kerns

    2016-08-01

    Full Text Available Nearly 50% of cancer patients undergo radiotherapy. Late radiotherapy toxicity affects quality-of-life in long-term cancer survivors and risk of side-effects in a minority limits doses prescribed to the majority of patients. Development of a test predicting risk of toxicity could benefit many cancer patients. We aimed to meta-analyze individual level data from four genome-wide association studies from prostate cancer radiotherapy cohorts including 1564 men to identify genetic markers of toxicity. Prospectively assessed two-year toxicity endpoints (urinary frequency, decreased urine stream, rectal bleeding, overall toxicity and single nucleotide polymorphism (SNP associations were tested using multivariable regression, adjusting for clinical and patient-related risk factors. A fixed-effects meta-analysis identified two SNPs: rs17599026 on 5q31.2 with urinary frequency (odds ratio [OR] 3.12, 95% confidence interval [CI] 2.08–4.69, p-value 4.16 × 10−8 and rs7720298 on 5p15.2 with decreased urine stream (OR 2.71, 95% CI 1.90–3.86, p-value = 3.21 × 10−8. These SNPs lie within genes that are expressed in tissues adversely affected by pelvic radiotherapy including bladder, kidney, rectum and small intestine. The results show that heterogeneous radiotherapy cohorts can be combined to identify new moderate-penetrance genetic variants associated with radiotherapy toxicity. The work provides a basis for larger collaborative efforts to identify enough variants for a future test involving polygenic risk profiling.

  13. Meta-analysis of Genome Wide Association Studies Identifies Genetic Markers of Late Toxicity Following Radiotherapy for Prostate Cancer.

    Science.gov (United States)

    Kerns, Sarah L; Dorling, Leila; Fachal, Laura; Bentzen, Søren; Pharoah, Paul D P; Barnes, Daniel R; Gómez-Caamaño, Antonio; Carballo, Ana M; Dearnaley, David P; Peleteiro, Paula; Gulliford, Sarah L; Hall, Emma; Michailidou, Kyriaki; Carracedo, Ángel; Sia, Michael; Stock, Richard; Stone, Nelson N; Sydes, Matthew R; Tyrer, Jonathan P; Ahmed, Shahana; Parliament, Matthew; Ostrer, Harry; Rosenstein, Barry S; Vega, Ana; Burnet, Neil G; Dunning, Alison M; Barnett, Gillian C; West, Catharine M L

    2016-08-01

    Nearly 50% of cancer patients undergo radiotherapy. Late radiotherapy toxicity affects quality-of-life in long-term cancer survivors and risk of side-effects in a minority limits doses prescribed to the majority of patients. Development of a test predicting risk of toxicity could benefit many cancer patients. We aimed to meta-analyze individual level data from four genome-wide association studies from prostate cancer radiotherapy cohorts including 1564 men to identify genetic markers of toxicity. Prospectively assessed two-year toxicity endpoints (urinary frequency, decreased urine stream, rectal bleeding, overall toxicity) and single nucleotide polymorphism (SNP) associations were tested using multivariable regression, adjusting for clinical and patient-related risk factors. A fixed-effects meta-analysis identified two SNPs: rs17599026 on 5q31.2 with urinary frequency (odds ratio [OR] 3.12, 95% confidence interval [CI] 2.08-4.69, p-value 4.16×10(-8)) and rs7720298 on 5p15.2 with decreased urine stream (OR 2.71, 95% CI 1.90-3.86, p-value=3.21×10(-8)). These SNPs lie within genes that are expressed in tissues adversely affected by pelvic radiotherapy including bladder, kidney, rectum and small intestine. The results show that heterogeneous radiotherapy cohorts can be combined to identify new moderate-penetrance genetic variants associated with radiotherapy toxicity. The work provides a basis for larger collaborative efforts to identify enough variants for a future test involving polygenic risk profiling.

  14. Whole transcriptome profiling of maize during early somatic embryogenesis reveals altered expression of stress factors and embryogenesis-related genes.

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    Stella A G D Salvo

    Full Text Available Embryogenic tissue culture systems are utilized in propagation and genetic engineering of crop plants, but applications are limited by genotype-dependent culture response. To date, few genes necessary for embryogenic callus formation have been identified or characterized. The goal of this research was to enhance our understanding of gene expression during maize embryogenic tissue culture initiation. In this study, we highlight the expression of candidate genes that have been previously regarded in the literature as having important roles in somatic embryogenesis. We utilized RNA based sequencing (RNA-seq to characterize the transcriptome of immature embryo explants of the highly embryogenic and regenerable maize genotype A188 at 0, 24, 36, 48, and 72 hours after placement of explants on tissue culture initiation medium. Genes annotated as functioning in stress response, such as glutathione-S-transferases and germin-like proteins, and genes involved with hormone transport, such as PINFORMED, increased in expression over 8-fold in the study. Maize genes with high sequence similarity to genes previously described in the initiation of embryogenic cultures, such as transcription factors BABY BOOM, LEAFY COTYLEDON, and AGAMOUS, and important receptor-like kinases such as SOMATIC EMBRYOGENESIS RECEPTOR LIKE KINASES and CLAVATA, were also expressed in this time course study. By combining results from whole genome transcriptome analysis with an in depth review of key genes that play a role in the onset of embryogenesis, we propose a model of coordinated expression of somatic embryogenesis-related genes, providing an improved understanding of genomic factors involved in the early steps of embryogenic culture initiation in maize and other plant species.

  15. Molecular regulation of somatic embryogenesis in potato: an auxin led perspective.

    Science.gov (United States)

    Sharma, Sanjeev Kumar; Millam, Steve; Hedley, Peter E; McNicol, Jim; Bryan, Glenn J

    2008-09-01

    Potato internodal segments (INS) treated with the auxin 2,4-dichlorophenoxyacetic acid can be induced to develop somatic embryos upon their transfer to an auxin-free medium, while the continuous presence of auxin in the medium suppresses the progression of embryogenically-induced somatic cells to embryos. We have employed these contrasting pathways, in combination with potato microarrays representing circa 10,000 genes, to profile global gene expression patterns during the progression of somatic embryogenesis in potato. The induction phase, characterised by the presence of auxin, was analysed by the direct comparison of RNA isolated from freshly excised (0 days) and embryogenically induced (14 days) INS explants. RNAs from embryo-forming (withdrawal of auxin after 14 days) and embryo-inhibitory (continuous presence of auxin) conditions, isolated over a range of time-points until the emergence of somatic embryos, were compared in a loop design to identify auxin responsive genes putatively involved in the process of somatic embryogenesis. A total of 402 transcripts were found to be showing significant differential expression patterns during somatic embryogenesis 'induction' phase, 524 during 'embryo-transition' phase, while 44 transcripts were common to both phases. Functional classification of these transcripts, using Gene Ontology vocabularies (molecular and biological), revealed that a significant proportion of transcripts were involved in processes which are more relevant to somatic embryogenesis such as apoptosis, development, reproduction, stress and signal transduction. This is the first study profiling global gene expression patterns during true somatic embryogenesis initiated from mature and completely differentiated explants and has enabled the description of stage-specific expression patterns of a large number of genes during potato somatic embryogenesis (PSE). The significance of the key identified genes during critical stages of somatic embryogenesis is

  16. Embryogenesis, a process of pattern formation

    Institute of Scientific and Technical Information of China (English)

    Meng-Xiang SUN

    2011-01-01

    @@ Plant embryogenesis is traditionally defined as a develop-mental process from zygote to mature embryo, which has the potential to form a complete plant (Bhojwani, 1974; Hu,2005).In dicotyledonous species, the fertilized egg or zygote usually divides according to a stereotyped pattern and gives rise to an embryo that consists of an embryonic shoot,cotyledons, hypocotyls, and an embryonic root.Thus, the basic body plan of the plant is established during the embryogenesis.Interestingly, the shoot-leaf-stem structure,not including the root, is repeatedly photocopied as a basic unit throughout plant vegetative growth (Wolpert et al.,2002).

  17. Somatic Embryogenesis in Crocus sativus L.

    Science.gov (United States)

    Sevindik, Basar; Mendi, Yesim Yalcin

    2016-01-01

    Saffron (Crocus sativus L.) is one of the most important species in Crocus genus because of its effective usage. It is not only a very expensive spice, but it has also a big ornamental plant potential. Crocus species are propagated by corm and seed, and male sterility is the most important problem of this species. Hence, somatic embryogenesis can be regarded as a strategic tool for the multiplication of saffron plants. In this chapter, the production of saffron corms via somatic embryogenesis is described.

  18. SERK1 links somatic embryogenesis to brassinosteroid signalling

    NARCIS (Netherlands)

    Kwaaitaal, M.A.C.J.

    2007-01-01

    Somatic embryogenesis, the phenomenon where a somatic cell supplied with the right cues can re-initiate embryogenesis, reveals the underlying totipotent character of plant cells. The acquisition of this totipotent state coincides with the expression of the Somatic Embryogenesis Receptor Kinase (SERK

  19. Chitinases and arabinogalactan proteins in somatic embryogenesis

    NARCIS (Netherlands)

    Hengel, van A.J.

    1998-01-01

    In vitro cultured carrot suspension cells can function as starting material for the generation of somatic embryos. Compounds secreted by suspension cells can influence the process of somatic embryogenesis. One class of such compounds, the secreted EP3 endochitinases,

  20. Bioreactors for Plant Embryogenesis and Beyond.

    Science.gov (United States)

    Fei, Liwen; Weathers, Pamela

    2016-01-01

    A variety of different bioreactors have been developed for use in initiating and cultivating somatic embryos. The various designs for embryogenesis and culture are critically evaluated here. Bioreactor optimization and operation methods are also described along with recommendations for use based on desired outcome.

  1. Cellular and molecular changes associated with somatic embryogenesis induction in Agave tequilana.

    Science.gov (United States)

    Portillo, L; Olmedilla, A; Santacruz-Ruvalcaba, F

    2012-10-01

    In spite of the importance of somatic embryogenesis for basic research in plant embryology as well as for crop improvement and plant propagation, it is still unclear which mechanisms and cell signals are involved in acquiring embryogenic competence by a somatic cell. The aim of this work was to study cellular and molecular changes involved in the induction stage in calli of Agave tequilana Weber cultivar azul in order to gain more information on the initial stages of somatic embryogenesis in this species. Cytochemical and immunocytochemical techniques were used to identify differences between embryogenic and non-embryogenic cells from several genotypes. Presence of granular structures was detected after somatic embryogenesis induction in embryogenic cells; composition of these structures as well as changes in protein and polysaccharide distribution was studied using Coomassie brilliant blue and Periodic Acid-Schiff stains. Distribution of arabinogalactan proteins (AGPs) and pectins was investigated in embryogenic and non-embryogenic cells by immunolabelling using anti-AGP monoclonal antibodies (JIM4, JIM8 and JIM13) as well as an anti-methyl-esterified pectin-antibody (JIM7), in order to evaluate major modifications in cell wall composition in the initial stages of somatic embryogenesis. Our observations pointed out that induction of somatic embryogenesis produced accumulation of proteins and polysaccharides in embryogenic cells. Presence of JIM8, JIM13 and JIM7 epitopes were detected exclusively in embryogenic cells, which supports the idea that specific changes in cell wall are involved in the acquisition of embryogenic competence of A. tequilana.

  2. Cloning and Expression Analysis of a Late Embryogenesis Abundant Protein Gene SpLea5 from Sesuviumportulacastrum%海马齿胚胎发育晚期丰富蛋白基因SpLea5的克隆与表达分析

    Institute of Scientific and Technical Information of China (English)

    付桂; 范伟; 畅文军; 张治礼

    2011-01-01

    根据筛选文库时获得的EST序列信息,利用RACE技术从海马齿根中分离获得了一个海马齿胚胎发育晚期丰富蛋白基因的全长cDNA,命名为SeLea5.序列分析结果表明,SpLea5基因cDNA全长685 bp,含有一个294 bD的完整开放阅读框,编码97个氨基酸残基;推测编码的氨基酸序列与柽柳、杨木樨、烟草、甜橙、温州蜜柑、麻风树和陆地棉中相廊基因的氨基酸序列一致性为54%、52%、48%、47%、47%、46%、44%、41%,在聚类分析时与高等植物聚为一类.SpLea5在海马齿植株中呈组成型表达,但根中表达最为丰富,茎和叶次之:海水、NaCl、PEG、ABA处理均能够诱导根部SpLea5基凶的表达.这些结果表明,SpLea5基因可能参与了海马齿对盐和十旱胁迫的分子响应.%Based on the EST sequences from a differentially expressed eDNA library of Sesuvium portulacastrum roots, the full-length eDNA of a late embryogenesis abundant pnotein gene designated as SpLea5 was cloned from S. portulacastrum roots. Sequence analysis showed that the SpLea5 eDNA contained 685 bp with an open reading frame (ORF) of 294 bp and encoded 97 amino acid residues. The deduced amino acid sequence shared the identity of 54%, 52%, 48%, 47%, 47%,46%, 46%, 44% and 41% with that from Tamarix androssowii, Populus suaveolens, Nicotiana tabacum, Citrus sinensis,Citrus unshiu, Jatropha curcas, Gossypium hirsutum, Glycine max and Ricinus communis, respectively. In phylogenetic tree the SpLea5 and other plant-derived Leas were grouped into one large cluster. Semi-quantitative RT-PCR analysis revealed that the SPLea5 was constitutively expressed in all tested organs but at different levels. The SpLea5 was strongly expressed in roots, but weakly in leaves and stems. The expression of SpLea5 was strongly regulated by seawater, NaCI, PEG and ABA, suggesting that the SpLea5 in S.portulacastrum may be involved in responses to salt stress and drought.

  3. Somatic embryogenesis in Lolium multiflorum suspension culture

    Directory of Open Access Journals (Sweden)

    Margarita Pavlova

    2014-01-01

    Full Text Available The embryogenic cell suspension was obtained from immature embryos of Lolium multiflorum through a callus culture. Somatic embryogenesis was induced by addition of 2,4-D, dicamba and picloram in 0,5 mg/l concentrations in MS liquid nutrient medium. It was shown that somatic embryos arised from single cells. In globular embryoids, the meristematic cells are characterized by the presence of phytoferritin inclusions in the leucoplasts.

  4. Transcriptome analysis of zebrafish embryogenesis using microarrays.

    Directory of Open Access Journals (Sweden)

    2005-08-01

    Full Text Available Zebrafish (Danio rerio is a well-recognized model for the study of vertebrate developmental genetics, yet at the same time little is known about the transcriptional events that underlie zebrafish embryogenesis. Here we have employed microarray analysis to study the temporal activity of developmentally regulated genes during zebrafish embryogenesis. Transcriptome analysis at 12 different embryonic time points covering five different developmental stages (maternal, blastula, gastrula, segmentation, and pharyngula revealed a highly dynamic transcriptional profile. Hierarchical clustering, stage-specific clustering, and algorithms to detect onset and peak of gene expression revealed clearly demarcated transcript clusters with maximum gene activity at distinct developmental stages as well as co-regulated expression of gene groups involved in dedicated functions such as organogenesis. Our study also revealed a previously unidentified cohort of genes that are transcribed prior to the mid-blastula transition, a time point earlier than when the zygotic genome was traditionally thought to become active. Here we provide, for the first time to our knowledge, a comprehensive list of developmentally regulated zebrafish genes and their expression profiles during embryogenesis, including novel information on the temporal expression of several thousand previously uncharacterized genes. The expression data generated from this study are accessible to all interested scientists from our institute resource database (http://giscompute.gis.a-star.edu.sg/~govind/zebrafish/data_download.html.

  5. Somatic Embryogenesis in Lily Bulb Scale Cultures

    Institute of Scientific and Technical Information of China (English)

    WANG Shasha; WANG Jingang; FAN Jinping; CHE Daidi

    2008-01-01

    Somatic embryogenesis from lily bulb scales has not been studied in details, although tissue culture methods have been applied to the propagation for decades. The effects of different kinds and concentration of auxins for oriental lily somatic embryogenesis were investigated (Lilium hybrida car. Sorbonne).2,4-dichlorophenoxyacetic acid (2,4-D), thidiazuron (TDZ) and α-naphthaleneacetic acid (NAA) media with benzyladenine(6-BA) and lactalbumin hydrolysate (LH) were used for embryogenic callus in the darkness. The best response onembryogenic callus formation was obtained on MS media supplemented 2, 4-D 2.0 mg·L-1,6-BA 0.5 mg·L-1 and LH 300 mg·L-1. Transfer embryogenic callus to the media with TDZ, 6-BA, kinetin (KT) supplemented 2, 4-D. The highest number of somatic embryos has been produced on medium with 0.5 mg.L-1 2, 4-D and 0.3 mg·L-1 KT. Germinated embryos with shoot axes were changed to MS media with 6-BA 0.5 mg· L-1. The results suggest that in vitro culture of somatic embryogenesis from lily bulb scales can be used for plant regeneration.

  6. Spaceflight reduces somatic embryogenesis in orchardgrass (Poaceae)

    Science.gov (United States)

    Conger, B. V.; Tomaszewski, Z. Jr; McDaniel, J. K.; Vasilenko, A.

    1998-01-01

    Somatic embryos initiate and develop from single mesophyll cells in in vitro cultured leaf segments of orchard-grass (Dactylis glomerata L.). Segments were plated at time periods ranging from 21 to 0.9 d (21 h) prior to launch on an 11 d spaceflight (STS-64). Using a paired t-test, there was no significant difference in embryogenesis from preplating periods of 14 d and 21 d. However, embryogenesis was reduced by 70% in segments plated 21 h before launch and this treatment was significant at P=0.0001. The initial cell divisions leading to embryo formation would be taking place during flight in this treatment. A higher ratio of anticlinal:periclinal first cell divisions observed in the flight compared to the control tissue suggests that microgravity affects axis determination and embryo polarity at a very early stage. A similar reduction in zygotic embryogenesis would reduce seed formation and have important implications for long-term space flight or colonization where seeds would be needed either for direct consumption or to grow another generation of plants.

  7. Transcriptome analysis of zebrafish embryogenesis using microarrays.

    Directory of Open Access Journals (Sweden)

    Sinnakaruppan Mathavan

    2005-08-01

    Full Text Available Zebrafish (Danio rerio is a well-recognized model for the study of vertebrate developmental genetics, yet at the same time little is known about the transcriptional events that underlie zebrafish embryogenesis. Here we have employed microarray analysis to study the temporal activity of developmentally regulated genes during zebrafish embryogenesis. Transcriptome analysis at 12 different embryonic time points covering five different developmental stages (maternal, blastula, gastrula, segmentation, and pharyngula revealed a highly dynamic transcriptional profile. Hierarchical clustering, stage-specific clustering, and algorithms to detect onset and peak of gene expression revealed clearly demarcated transcript clusters with maximum gene activity at distinct developmental stages as well as co-regulated expression of gene groups involved in dedicated functions such as organogenesis. Our study also revealed a previously unidentified cohort of genes that are transcribed prior to the mid-blastula transition, a time point earlier than when the zygotic genome was traditionally thought to become active. Here we provide, for the first time to our knowledge, a comprehensive list of developmentally regulated zebrafish genes and their expression profiles during embryogenesis, including novel information on the temporal expression of several thousand previously uncharacterized genes. The expression data generated from this study are accessible to all interested scientists from our institute resource database (http://giscompute.gis.a-star.edu.sg/~govind/zebrafish/data_download.html.

  8. Validation of transcutaneous bilirubin nomogram for identifying neonatal hyperbilirubinemia in healthy Chinese term and late-preterm infants: a multicenter study

    Directory of Open Access Journals (Sweden)

    Zhangbin Yu

    2014-06-01

    Full Text Available OBJECTIVE: to prospectively validate a previously constructed transcutaneous bilirubin (TcB nomogram for identifying severe hyperbilirubinemia in healthy Chinese term and late-preterm infants. METHODS: this was a multicenter study that included 9,174 healthy term and late-preterm infants in eight hospitals of China. TcB measurements were performed using a JM-103 bilirubinometer. TcB values were plotted on a previously developed TcB nomogram, to identify the predictive ability for subsequent significant hyperbilirubinemia. RESULTS: in the present study, 972 neonates (10.6% developed significant hyperbilirubinemia. The 40th percentile of the nomogram could identify all neonates who were at risk of significant hyperbilirubinemia, but with a low positive predictive value (PPV (18.9%. Of the 453 neonates above the 95th percentile, 275 subsequently developed significant hyperbilirubinemia, with a high PPV (60.7%, but with low sensitivity (28.3%. The 75th percentile was highly specific (81.9% and moderately sensitive (79.8%. The area under the curve (AUC for the TcB nomogram was 0.875. CONCLUSIONS: this study validated the previously developed TcB nomogram, which could be used to predict subsequent significant hyperbilirubinemia in healthy Chinese term and late-preterm infants. However, combining TcB nomogram and clinical risk factors could improve the predictive accuracy for severe hyperbilirubinemia, which was not assessed in the study. Further studies are necessary to confirm this combination.

  9. How microspores transform into haploid embryos: changes associated with embryogenesis induction and microspore-derived embryogenesis.

    Science.gov (United States)

    Seguí-Simarro, José M; Nuez, Fernando

    2008-09-01

    Microspore embryogenesis is the most powerful androgenic pathway to produce haploid and doubled haploid plants. To deviate a microspore toward embryogenesis, a number of factors, different for each species, must concur at the same time and place. Once induced, the microspore undergoes numerous changes at different levels, from overall morphology to gene expression. Induction of microspore embryogenesis not only implies the expression of an embryogenic program, but also a stress-related cellular response and a repression of the gametophytic program to revert the microspore to a totipotent status. In this review, we compile the most recent advances in the understanding of the changes undergone by the induced microspore to readapt to the new developmental scenario. We devote special attention to the efforts made to uncover changes in the transcriptome of the induced microspore and microspore-derived embryo (MDE). Finally, we discuss the influence that an in vitro environment exerts over the MDE, as compared with its zygotic counterpart.

  10. Studies on the Factors Affecting on Somatic Embryogenesis in Soybean

    Institute of Scientific and Technical Information of China (English)

    WANG Ping; WANG Gang; LU Wen-he; JI Jing; YANG Qing-kai

    2002-01-01

    The effects of the concentration of MS micro salts, 2,4-dichlorophenoxyacetic acid (2,4-D), 3-naphthalene acetic acid (NAA), proline and adenine on callus formation and somatic embryogenesis were investigated using orthogonal design with immature cotyledons of soybean. The results showed that the role of concentration of micro salts on frequency of callus formation and somatic embryogenesis were significant. MS medium supplemented with 2,4-D, NAA, proline and adenine could stimulate callus formation. The concentration of MS micro salts possessed obvious effects on somatic embryogenesis of soybean. The category and concentration of the hormone needed were different among genotypes when embryogenesis were induced.

  11. In-depth proteomics characterization of embryogenesis of the honey bee worker (Apis mellifera ligustica).

    Science.gov (United States)

    Fang, Yu; Feng, Mao; Han, Bin; Lu, Xiaoshan; Ramadan, Haitham; Li, Jianke

    2014-09-01

    Identifying proteome changes of honey bee embryogenesis is of prime importance for unraveling the molecular mechanisms that they underlie. However, many proteomic changes during the embryonic period are not well characterized. We analyzed the proteomic alterations over the complete time course of honey bee worker embryogenesis at 24, 48, and 72 h of age, using mass spectrometry-based proteomics, label-free quantitation, and bioinformatics. Of the 1460 proteins identified the embryo of all three ages, the core proteome (proteins shared by the embryos of all three ages, accounting for 40%) was mainly involved in protein synthesis, metabolic energy, development, and molecular transporter, which indicates their centrality in driving embryogenesis. However, embryos at different developmental stages have their own specific proteome and pathway signatures to coordinate and modulate developmental events. The young embryos (proteins related to nutrition storage and nucleic acid metabolism may correlate with the cell proliferation occurring at this stage. The middle aged embryos (24-48 h) enhanced expression of proteins associated with cell cycle control, transporters, antioxidant activity, and the cytoskeleton suggest their roles to support rudimentary organogenesis. Among these proteins, the biological pathways of aminoacyl-tRNA biosynthesis, β-alanine metabolism, and protein export are intensively activated in the embryos of middle age. The old embryos (48-72 h) elevated expression of proteins implicated in fatty acid metabolism and morphogenesis indicate their functionality for the formation and development of organs and dorsal closure, in which the biological pathways of fatty acid metabolism and RNA transport are highly activated. These findings add novel understanding to the molecular details of honey bee embryogenesis, in which the programmed activation of the proteome matches with the physiological transition observed during embryogenesis. The identified biological

  12. Usefulness of residual ischemic myocardium within prior infarct zone for identifying patients at high risk late after acute myocardial infarction.

    Science.gov (United States)

    Brown, K A; Weiss, R M; Clements, J P; Wackers, F J

    1987-07-01

    This study examines the prognostic implications of ischemia within the territory of a prior acute myocardial infarction (AMI) vs ischemia at a distance, which develops late after AMI. Sixty-one consecutive patients who underwent both exercise thallium-201 (TI-201) imaging and cardiac catheterization for evaluation of chest pain that developed after discharge from the hospital for AMI form the study group. Mean interval between infarction to the TI-201 study was 10 +/- 17 months. Initial and 2-hour delay TI-201 images were analyzed quantitatively to determine the presence and location (within vs outside the prior infarct zone) of TI-201 redistribution, a marker of ischemic viable myocardium. TI-201 imaging results were separated into 3 groups based on presence and location of TI-201 redistribution: no significant TI-201 redistribution was found in 16 patients; in 29, TI-201 redistribution was confined to the infarct zone; and in 16, TI-201 redistribution was outside the infarct zone. Stepwise multivariate logistic regression analysis was used to examine the comparative ability of TI-201 results and other patient variables to predict cardiac events. For total cardiac events (cardiac death, recurrent nonfatal AMI, unstable angina and coronary revascularization), both the presence of any TI-201 redistribution and multivessel angiographic coronary artery disease were significant predictors. However, when coronary revascularization was excluded as an endpoint, TI-201 redistribution limited to the prior infarct zone was the only significant predictor of cardiac events. All 8 cardiac events occurred in patients with T1-201 redistribution limited to the infart zone.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Hemoglobins, programmed cell death and somatic embryogenesis.

    Science.gov (United States)

    Hill, Robert D; Huang, Shuanglong; Stasolla, Claudio

    2013-10-01

    Programmed cell death (PCD) is a universal process in all multicellular organisms. It is a critical component in a diverse number of processes ranging from growth and differentiation to response to stress. Somatic embryogenesis is one such process where PCD is significantly involved. Nitric oxide is increasingly being recognized as playing a significant role in regulating PCD in both mammalian and plant systems. Plant hemoglobins scavenge NO, and evidence is accumulating that events that modify NO levels in plants also affect hemoglobin expression. Here, we review the process of PCD, describing the involvement of NO and plant hemoglobins in the process. NO is an effector of cell death in both plants and vertebrates, triggering the cascade of events leading to targeted cell death that is a part of an organism's response to stress or to tissue differentiation and development. Expression of specific hemoglobins can alter this response in plants by scavenging the NO, thus, interrupting the death process. Somatic embryogenesis is used as a model system to demonstrate how cell-specific expression of different classes of hemoglobins can alter the embryogenic process, affecting hormone synthesis, cell metabolite levels and genes associated with PCD and embryogenic competence. We propose that plant hemoglobins influence somatic embryogenesis and PCD through cell-specific expression of a distinct plant hemoglobin. It is based on the premise that both embryogenic competence and PCD are strongly influenced by cellular NO levels. Increases in cellular NO levels result in elevated Zn(2+) and reactive-oxygen species associated with PCD, but they also result in decreased expression of MYC2, a transcription factor that is a negative effector of indoleacetic acid synthesis, a hormone that positively influences embryogenic competence. Cell-specific hemoglobin expression reduces NO levels as a result of NO scavenging, resulting in cell survival.

  14. Genetic Regulatory Networks in Embryogenesis and Evolution

    Science.gov (United States)

    1998-01-01

    The article introduces a series of papers that were originally presented at a workshop titled Genetic Regulatory Network in Embryogenesis and Evaluation. Contents include the following: evolution of cleavage programs in relationship to axial specification and body plan evolution, changes in cell lineage specification elucidate evolutionary relations in spiralia, axial patterning in the leech: developmental mechanisms and evolutionary implications, hox genes in arthropod development and evolution, heterochronic genes in development and evolution, a common theme for LIM homeobox gene function across phylogeny, and mechanisms of specification in ascidian embryos.

  15. Have necrohormones a role in embryogenesis?

    Directory of Open Access Journals (Sweden)

    P. R. Bell

    2014-01-01

    Full Text Available The recognition of apoptosis (programmed cell death as an accompaniment of normal development, the products released by the protoplasts undergoing self-destruction being utilized by adjacent living cells, stimulates renewed interest in Haberlandt's concept of "necrohormones" playing a role in apomictic reproduction. Recent work on somatic embryogenesis in carrot shows that regular death of certain cells in embryogenic cultures satifies the criteria of apoptosis. Similar observations have been made with embryogenic cultures of Picea abies. Haberlandt's claim that cell death induced by injury adjacent to an ovule in Oenothera could lead to parthenogenesis, despite conflicting evidence from later experimenters, is worthy of reexamination.

  16. Identifying the pollen of an extinct spruce species in the Late Quaternary sediments of the Tunica Hills region, south-eastern United States

    Science.gov (United States)

    Luke Mander,; Jacklyn Rodriguez,; Pietra G. Mueller,; Jackson, Stephen T.; Surangi W. Punyasena,

    2014-01-01

    Late Quaternary fluvial deposits in the Tunica Hills region of Louisiana and Mississippi are rich in spruce macrofossils of the extinct species Picea critchfieldii, the one recognized plant extinction of the Late Quaternary. However, the morphology of P. critchfieldii pollen is unknown, presenting a barrier to the interpretation of pollen spectra from the last glacial of North America. To address this issue, we undertook a morphometric study of Picea pollen from Tunica Hills. Morphometric data, together with qualitative observations of pollen morphology using Apotome fluorescence microscopy, indicate that Picea pollen from Tunica Hills is morphologically distinct from the pollen of P. glauca, P. mariana and P. rubens. Measurements of grain length, corpus width and corpus height indicate that Picea pollen from Tunica Hills is larger than the pollen of P. mariana and P. rubens, and is slightly larger than P. glauca pollen. We argue that the morphologically distinctive Tunica Hills Picea pollen was probably produced by the extinct spruce species P. critchfieldii. These morphological differences could be used to identify P. critchfieldii in existing and newly collected pollen records, which would refine its paleoecologic and biogeographic history and clarify the nature and timing of its extinction in the Late Quaternary.

  17. Validation of transcutaneous bilirubin nomogram for identifying neonatal hyperbilirubinemia in healthy Chinese term and late-preterm infants: a multicenter study.

    Science.gov (United States)

    Yu, Zhangbin; Han, Shuping; Wu, Jinxia; Li, Mingxia; Wang, Huaiyan; Wang, Jimei; Liu, Jiebo; Pan, Xinnian; Yang, Jie; Chen, Chao

    2014-01-01

    to prospectively validate a previously constructed transcutaneous bilirubin (TcB) nomogram for identifying severe hyperbilirubinemia in healthy Chinese term and late-preterm infants. this was a multicenter study that included 9,174 healthy term and late-preterm infants in eight hospitals of China. TcB measurements were performed using a JM-103 bilirubinometer. TcB values were plotted on a previously developed TcB nomogram, to identify the predictive ability for subsequent significant hyperbilirubinemia. in the present study, 972 neonates (10.6%) developed significant hyperbilirubinemia. The 40(th) percentile of the nomogram could identify all neonates who were at risk of significant hyperbilirubinemia, but with a low positive predictive value (PPV) (18.9%). Of the 453 neonates above the 95(th) percentile, 275 subsequently developed significant hyperbilirubinemia, with a high PPV (60.7%), but with low sensitivity (28.3%). The 75(th) percentile was highly specific (81.9%) and moderately sensitive (79.8%). The area under the curve (AUC) for the TcB nomogram was 0.875. this study validated the previously developed TcB nomogram, which could be used to predict subsequent significant hyperbilirubinemia in healthy Chinese term and late-preterm infants. However, combining TcB nomogram and clinical risk factors could improve the predictive accuracy for severe hyperbilirubinemia, which was not assessed in the study. Further studies are necessary to confirm this combination. Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  18. A Late Glacial Environmental Reconstruction performed on Lacustrine Sediments from the Southern Tibetan Plateau identifies regional Monsoon Variations

    Science.gov (United States)

    Henkel, K.; Ahlborn, M.; Haberzettl, T.; Alivernini, M.; Kasper, T.; Thiele, A.; St-Onge, G.; Daut, G.; Frenzel, P.; Gleixner, G.; Wang, J.; Zhu, L.; Maeusbacher, R.

    2014-12-01

    The Tibetan Plateau (TP) is very sensitive to climate variations and is therefore an ideal study site to investigate past climate changes. Influenced by the Asian Monsoon system, the numerous lake systems on the TP serve as valuable archives for past hydrological changes, which are assumed to be caused by variations in strength and extent of the monsoonal impact. The lacustrine record from the terminal lake Tangra Yumco (4540 m a.s.l., 31°13'N, 86°43'E) consists of an interbedding of fine-grained silty sediments with laminations of different thicknesses (sub-mm to cm) and partly intercalated blackish sandy layers. Thin section analysis in the laminated areas reveals cyclic laminations composed of a carbonate and a detrital layer. Homogenous intervals represent turbidite deposits which are further detected based on lithology, radiography as well as changes in the water content, grain size, Ti-values (XRF) and in the paleomagnetic parameter median destructive field. The chronology is based on 27 AMS-radiocarbon ages on bulk organic matter and one piece of wood, which is of terrestrial origin. To determine a possible carbon reservoir effect, additional surface sediment samples and one modern aquatic plant were measured. The calculated reservoir effect of 2,120 +110/-90 years is assumed to be constant over the time and thus the base of the record reveals a corrected radiocarbon age of 17,270 +325/-310 cal BP. Additionally, investigations on paleomagnetic secular variations were carried out, showing that since 15,900 cal BP the record preserved a well-defined magnetization recording a genuine paleomagnetic signal. Regarding the geochemical (organic and inorganic), sedimentological, mineralogical and micropaleontological analyses, a low lake level with a high terrestrial input is observed for the Late Glacial. At 15.6 ka cal BP, a change in the sediment accumulation rate, increased allochthoneous input and changing ostracod fauna point to an increasing lake level. In

  19. Molecular identity of the late sodium current in adult dog cardiomyocytes identified by Nav1.5 antisense inhibition.

    Science.gov (United States)

    Maltsev, Victor A; Kyle, John W; Mishra, Sudhish; Undrovinas, Abertas

    2008-08-01

    Late Na(+) current (I(NaL)) is a major component of the action potential plateau in human and canine myocardium. Since I(NaL) is increased in heart failure and ischemia, it represents a novel potential target for cardioprotection. However, the molecular identity of I(NaL) remains unclear. We tested the hypothesis that the cardiac Na(+) channel isoform (Na(v)1.5) is a major contributor to I(NaL) in adult dog ventricular cardiomyocytes (VCs). Cultured VCs were exposed to an antisense morpholino-based oligonucleotide (Na(v)1.5 asOligo) targeting the region around the start codon of Na(v)1.5 mRNA or a control nonsense oligonucleotide (nsOligo). Densities of both transient Na(+) current (I(NaT)) and I(NaL) (both in pA/pF) were monitored by whole cell patch clamp. In HEK293 cells expressing Na(v)1.5 or Na(v)1.2, Na(v)1.5 asOligo specifically silenced functional expression of Na(v)1.5 (up to 60% of the initial I(NaT)) but not Na(v)1.2. In both nsOligo-treated controls and untreated VCs, I(NaT) and I(NaL) remained unchanged for up to 5 days. However, both I(NaT) and I(NaL) decreased exponentially with similar time courses (tau = 46 and 56 h, respectively) after VCs were treated with Na(v)1.5 asOligo without changes in 1) decay kinetics, 2) steady-state activation and inactivation, and 3) the ratio of I(NaL) to I(NaT). Four days after exposure to Na(v)1.5 asOligo, I(NaT) and I(NaL) amounted to 68 +/- 6% (mean +/- SE; n = 20, P < 0.01) and 60 +/- 7% (n = 11, P < 0.018) of those in VCs treated by nsOligo, respectively. We conclude that in adult dog heart Na(v)1.5 sodium channels have a "functional half-life" of approximately 35 h (0.69tau) and make a major contribution to I(NaL).

  20. The use of somatic embryogenesis for plant propagation in cassava

    NARCIS (Netherlands)

    Raemakers, K.; Jacobsen, E.; Visser, R.

    2000-01-01

    In cassava, somatic embryogenesis starts with the culture of leaf explants on solid Murashige and Skoog-based medium supplemented with auxins. Mature somatic embryos are formed within 6 wk. The cotyledons of the primary somatic embryos are used as explants for a new cycle of somatic embryogenesis. T

  1. Boron-Mediated Plant Somatic Embryogenesis: A Provocative Model

    Directory of Open Access Journals (Sweden)

    Dhananjay K. Pandey

    2012-01-01

    Full Text Available A central question in plant regeneration biology concerns the primary driving forces invoking the acquisition of somatic embryogenesis. Recently, the role of micronutrient boron (B in the initiation and perpetuation of embryogenesis has drawn considerable attention within the scientific community. This interest may be due in part to the bewildering observation that the system-wide induction of embryogenic potential significantly varied in response to a minimal to optimal supply of B (minimal ≤ 0.1 mM, optimal = 0.1 mM. At the cellular level, certain channel proteins and cell wall-related proteins important for the induction of embryogenesis have been shown to be transcriptionally upregulated in response to minimal B supply suggesting the vital role of B in the induction of embryogenesis. At the molecular level, minimal to no B supply increased the endogenous level of auxin, which subsequently influenced the auxin-inducible somatic embryogenesis receptor kinases, suggesting the role of B in the induction of embryogenesis. Also, minimal B concentration may “turn on” other genetic and/or cellular transfactors reported earlier to be essential for cell-restructuring and induction of embryogenesis. In this paper, both the direct and indirect roles of B in the induction of somatic embryogenesis are highlighted and suggested for future validation.

  2. The use of somatic embryogenesis for plant propagation in cassava

    NARCIS (Netherlands)

    Raemakers, K.; Jacobsen, E.; Visser, R.

    2000-01-01

    In cassava, somatic embryogenesis starts with the culture of leaf explants on solid Murashige and Skoog-based medium supplemented with auxins. Mature somatic embryos are formed within 6 wk. The cotyledons of the primary somatic embryos are used as explants for a new cycle of somatic embryogenesis. T

  3. Microspore embryogenesis: reprogramming cell fate from pollen to embryo development

    NARCIS (Netherlands)

    Hui Li,

    2014-01-01

    Microspore embryogenesis is an expression of plant cell totipotency that leads to the production of haploid embryos. Besides being a widely exploited plant breeding tool, microspore embryogenesis is also a fascinating system that can be used to obtain a deeper mechanistic understanding of plant toti

  4. SOMATIC EMBRYOGENESIS FROM MERISTEM EXPLANTS OF GINGER

    Directory of Open Access Journals (Sweden)

    OTIH ROSTIANA

    2008-01-01

    Full Text Available The use of planting materials from in vitro culture, especially derived from somatic em -bryos has some advantages such as genetically stable and pathogen-free. Meristem culture of ginger through somatic embryogenesis could be a potential method for producing pathogen-free planting materials. Somatic embryogenesis on ginger was performed to obtain vigorous plantlets having the same rhizome size as the mother plant. Callus was induced from meristem tissue of inner bud of Indonesian ginger rhizome Var. Cimanggu-1 and consecutively subcultured into certain media at each steps of experiments. The vigorous embryogenic calli were observed on MS medium containing 100 mgl-1 glutamine and 2% sucrose with addition of 1.0 mgl-1 2,4-D + 3.0 mgl-1 BA. The highest number of somatic embryos (about 82.0.g-1 friable calli was achieved on that medium, 4 weeks after culturing. Furthermore, the optimum growth of embryogenic calli containing somatic embryo was obtained on MS medium enriched with 6% sucrose. The high-est number of mature somatic embryos (57.2 embryos was achieved on MS medium, 18 days after incubation. The regeneration potency of somatic embryos obtained from ginger meristem was 51.20%.g-1 friable callus. The valuable result of this study was the achievement of normal rhizome size of regenerated plantlets, instead of micro rhizome.

  5. Studies for Somatic Embryogenesis in Sweet Potato

    Science.gov (United States)

    Bennett, J. Rasheed; Prakash, C. S.

    1997-01-01

    The purpose of this study was to improve the somatic embryo (SE) system for plant production of sweet potato (Ipomoea batatas L(Lam)). Explants isolated from SE-derived sweet potato plants were compared with control (non SE-derived) plants for their competency for SE production. Leaf explants were cultured on Murashige-Skoog (MS) medium with 2,4-dichlorophenoxy acetic acid (0.2 mg/L) and 6-benzylaminopurine (2.5 mg/L) for 2 weeks in darkness and transferred to MS medium with abscisic acid (2.5 mg/L). Explants isolated from those plants developed through somatic embryogenesis produced new somatic embryos rapidly and in higher frequency than those isolated from control plants They also appeared to grow faster in tissue culture than the control plants. Current studies in the laboratory are examining whether plants derived from a cyclical embryogenesis system (five cycles) would have any further positive impact on the rapidity and frequency of somatic embryo development. More detailed studies using electron microscopy are expected to show the point of origin of the embryos and to allow determination of their quality throughout the cyclical process. This study may facilitate improved plant micropropagation, gene transfer and germplasm conservation in sweet potato.

  6. Studies on Somatic Embryogenesis in Sweetpotato

    Science.gov (United States)

    Bennett, J. Rasheed; Prakash, C. S.

    1997-01-01

    The purpose of this study was to improve the somatic embryo (SE) system for plant production of sweetpotato Ipomoea batatas L.(Lam)l. Explants isolated from SE-derived sweet potato plants were compared with control (non SE-derived) plants for their competency for SE production. Leaf explants were cultured on Murashige-Skoog (MS) medium with 2,4-dichlorophenoxy acetic acid (0.2 mg/L) and 6-benzylaminopurine (2.5 mg/L) for 2 weeks in darkness and transferred to MS medium with abscisic acid (2.5 Explants isolated from those plants developed through somatic embryo-genesis produced new somatic embryos rapidly and in higher frequency than those isolated from control plants. They also appeared to grow faster in tissue culture than the control plants. Current studies in the laboratory are examining whether plants derived from a cyclical embryogenesis system (five cycles) would have any further positive impact on the rapidity and frequency of somatic embryo development. More detailed studies using electron microscopy are expected to show the point of origin of the embryos and to allow determination of their quality throughout the cyclical process. This study may facilitate improved plant micropropagation, gene transfer and germplasm conservation in sweet potato.

  7. Changes in pectins and MAPKs related to cell development during early microspore embryogenesis in Quercus suber L.

    Science.gov (United States)

    Ramírez, Carmen; Testillano, Pilar S; Pintos, Beatriz; Moreno-Risueño, Miguel A; Bueno, María A; Risueño, María C

    2004-07-01

    The occurrence and significance of changes in cell wall components and signalling molecules has been investigated during early microspore embryogenesis in cork oak (Quercus suber L.) in relation to cell proliferation and cell differentiation. Microspore embryogenesis has been induced in in vitro anther cultures of Q. suber by the application of a stress treatment of 33 degrees C. After the treatment, microspores at the responsive developmental stage of vacuolate microspore switched towards proliferation and the embryogenesis pathway to further produce haploid plantlets. Ultrastructural and immunocytochemical analysis revealed changes in cell organisation after induction at different developmental stages, the cellular features displayed being in relation to the activation of proliferative activity and the beginning of differentiation in young and late proembryos. Immunogold labelling with JIM5 and JIM7 antibodies showed a different presence of pectin and level of its esterification in cell walls at different developmental stages. Non-esterified pectins were found in higher proportions in cells of late proembryos, suggesting that pectin de-esterification could be related to the beginning of differentiation. The presence and subcellular distribution of Erk 1/2 MAPK homologues have been investigated by immunoblotting, immunofluorescence and immunogold labelling. The results showed an increase in the expression of these proteins with a high presence in the nucleus, during early microspore proembryos development. The reported changes during early microspore embryogenesis are modulated in relation to proliferation and differentiation events. These findings provided new evidences for a role of MAPK signalling pathways in early microspore embryogenesis, specifically in proliferation, and would confer information for the cell fate and the direction of the cell development.

  8. Identifying the ionically bound cell wall and intracellular glycoside hydrolases in late growth stage Arabidopsis stems: implications for the genetic engineering of bioenergy crops

    Directory of Open Access Journals (Sweden)

    Hui eWEI

    2015-05-01

    Full Text Available Identifying the cell wall-ionically bound glycoside hydrolases (GHs in Arabidopsis stems is important for understanding the regulation of cell wall integrity. For cell wall proteomics studies, the preparation of clean cell wall fractions is a challenge since cell walls constitute an open compartment, which is more likely to contain a mixture of intracellular and extracellular proteins due to cell leakage at the late growth stage. Here, we utilize a CaCl2-extraction procedure to isolate non-structural proteins from Arabidopsis whole stems, followed by the in-solution and in-gel digestion methods coupled with Nano-LC-MS/MS, bioinformatics and literature analyses. This has led to the identification of 75 proteins identified using the in-solution method and 236 proteins identified by the in-gel method, among which about 10% of proteins predicted to be secreted. Together, eight cell wall proteins, namely AT1G75040, AT5G26000, AT3G57260, AT4G21650, AT3G52960, AT3G49120, AT5G49360 and AT3G14067, were identified by the in-solution method; among them, three were the GHs (AT5G26000, myrosinase 1, GH1; AT3G57260, β-1,3-glucanase 2, GH17; AT5G49360, bifunctional XYL 1/α-L-arabinofuranosidase, GH3. Moreover, four more GHs: AT4G30270 (xyloglucan endotransferase, GH16, AT1G68560 (bifunctional α-l-arabinofuranosidase/XYL, GH31, AT1G12240 (invertase, GH32 and AT2G28470 (β-galactosidase 8, GH35, were identified by the in-gel solution method only. Notably, more than half of above identified GHs are xylan- or hemicellulose-modifying enzymes, and will likely have an impact on cellulose accessibility, which is a critical factor for downstream enzymatic hydrolysis of plant tissues for biofuels production. The implications of these cell wall proteins identified at the late growth stage for the genetic engineering of bioenergy crops are discussed.

  9. The embryogenesis of the tick Rhipicephalus (Boophilus) microplus: the establishment of a new chelicerate model system.

    Science.gov (United States)

    Santos, Vitória Tobias; Ribeiro, Lupis; Fraga, Amanda; de Barros, Cíntia Monteiro; Campos, Eldo; Moraes, Jorge; Fontenele, Marcio Ribeiro; Araújo, Helena Marcolla; Feitosa, Natalia Martins; Logullo, Carlos; da Fonseca, Rodrigo Nunes

    2013-12-01

    Chelicerates, which include spiders, ticks, mites, scorpions, and horseshoe crabs, are members of the phylum Arthropoda. In recent years, several molecular experimental studies of chelicerates have examined the embryology of spiders; however, the embryology of other groups, such as ticks (Acari: Parasitiformes), has been largely neglected. Ticks and mites are believed to constitute a monophyletic group, the Acari. Due to their blood-sucking activities, ticks are also known to be vectors of several diseases. In this study, we analyzed the embryonic development of the cattle tick, Rhipicephalus (Boophilus) microplus (Acari: Ixodidae). First, we developed an embryonic staging system consisting of 14 embryonic stages. Second, histological analysis and antibody staining unexpectedly revealed the presence of a population of tick cells with similar characteristics to the spider cumulus. Cumulus cell populations also exist in other chelicerates; these cells are responsible for the breaking of radial symmetry through bone morphogenetic protein signaling. Third, it was determined that the posterior (opisthosomal) embryonic region of R. microplus is segmented. Finally, we identified the presence of a transient ventral midline furrow and the formation and regression of a fourth leg pair; these features may be regarded as hallmarks of late tick embryogenesis. Importantly, most of the aforementioned features are absent from mite embryos, suggesting that mites and ticks do not constitute a monophyletic group or that mites have lost these features. Taken together, our findings provide fundamental common ground for improving knowledge regarding tick embryonic development, thereby facilitating the establishment of a new chelicerate model system. Copyright © 2013 Wiley Periodicals, Inc.

  10. Oil Body Biogenesis during Brassica napus Embryogenesis

    Institute of Scientific and Technical Information of China (English)

    Yu-Qing He; Yan Wu

    2009-01-01

    Although the oil body is known to be an important membrane enclosed compartment for oil storage in seeds, we have little understanding about its biogenesis during embryogenesis. In the present study we investigated the oil body emergence and variations in Brassica napus cv. Topas. The results demonstrate that the oil bodies could be detected already at the heart stage, at the same time as the embryos began to tum green, and the starch grains accumulated in the chloroplast stroma. In comparison, we have studied the development of oil bodies between Arabidopsis thaliana wild type (Col) and the low-seed-oil mutant wrinkled1-3. We observed that the oil body development in the embryos of Col is similar to that of B. napus cv. Topas, and that the size of the oil bodies was obviously smaller in the embryos of wrinkled1-3. Our results suggest that the oil body biogenesis might be coupled with the embryo chloroplast.

  11. The torpedo (DER) receptor tyrosine kinase is required at multiple times during Drosophila embryogenesis.

    Science.gov (United States)

    Clifford, R; Schüpbach, T

    1992-07-01

    The torpedo (DER) gene of Drosophila, which encodes a receptor tyrosine kinase of the EGF receptor subfamily, is essential for oogenesis, embryogenesis and imaginal disc development. To gain insight into the nature of the signals transduced by the torpedo product, we have characterized the gene's loss-of-function phenotype in the embryo. Through the induction of germline clones, we provide a genetic demonstration that maternal torpedo product does not contribute to zygotic development. Thus, the embryonic lethal phenotypes examined accurately reflect the consequences of eliminating all gene activity from the zygote. Temperature-shift experiments with the conditional allele topIF26 show that torpedo is required at two distinct times during embryonic development: the gene is first needed for germband retraction and for the production of anterior, posterior and ventral cuticle, then later for the secretion of ventral denticles. Since denticle formation can be severely disrupted in topIF26 animals without affecting cuticle production, the early and late requirements for torpedo appear to be functionally unrelated. torpedo, therefore, is required at multiple times in the development of the ventral epidermis, and may transduce qualitatively different signals. Since the early requirement for torpedo correlates with the first visible defect in embryonic development, increased cell death in the amnioserosa, cephalic ectoderm and ventral epidermis, the abnormalities in cuticle production and germband shortening seen in the mutant may be secondary consequences of a primary defect in cell viability. Given that the onset of cell death in torpedo embryos is not preceded by any obvious defects in mitogenesis, the establishment of cell identities or the maintenance of gene expression, it is possible that torpedo transduces a signal necessary for cell survival per se during early embryogenesis. During late embryogenesis, torpedo may mediate the reception of a second signal which

  12. A Next-Generation Sequencing Approach to Identify Gene Mutations in Early- and Late-Onset Hypertrophic Cardiomyopathy Patients of an Italian Cohort.

    Science.gov (United States)

    Rubattu, Speranza; Bozzao, Cristina; Pennacchini, Ermelinda; Pagannone, Erika; Musumeci, Beatrice Maria; Piane, Maria; Germani, Aldo; Savio, Camilla; Francia, Pietro; Volpe, Massimo; Autore, Camillo; Chessa, Luciana

    2016-07-30

    Sequencing of sarcomere protein genes in patients fulfilling the clinical diagnostic criteria for hypertrophic cardiomyopathy (HCM) identifies a disease-causing mutation in 35% to 60% of cases. Age at diagnosis and family history may increase the yield of mutations screening. In order to assess whether Next-Generation Sequencing (NGS) may fulfil the molecular diagnostic needs in HCM, we included 17 HCM-related genes in a sequencing panel run on PGM IonTorrent. We selected 70 HCM patients, 35 with early (≤25 years) and 35 with late (≥65 years) diagnosis of disease onset. All samples had a 98.6% average of target regions, with coverage higher than 20× (mean coverage 620×). We identified 41 different mutations (seven of them novel) in nine genes: MYBPC3 (17/41 = 41%); MYH7 (10/41 = 24%); TNNT2, CAV3 and MYH6 (3/41 = 7.5% each); TNNI3 (2/41 = 5%); GLA, MYL2, and MYL3 (1/41=2.5% each). Mutation detection rate was 30/35 (85.7%) in early-onset and 8/35 (22.9%) in late-onset HCM patients, respectively (p < 0.0001). The overall detection rate for patients with positive family history was 84%, and 90.5% in patients with early disease onset. In our study NGS revealed higher mutations yield in patients with early onset and with a family history of HCM. Appropriate patient selection can increase the yield of genetic testing and make diagnostic testing cost-effective.

  13. The importance of SERINE DECARBOXYLASE1 (SDC1) and ethanolamine biosynthesis during embryogenesis of Arabidopsis thaliana.

    Science.gov (United States)

    Yunus, Ian Sofian; Liu, Yu-Chi; Nakamura, Yuki

    2016-11-01

    In plants, ethanolamine is considered a precursor for the synthesis of choline, which is an essential dietary nutrient for animals. An enzyme serine decarboxylase (SDC) has been identified and characterized in Arabidopsis, which directly converts serine to ethanolamine, a precursor to phosphorylethanolamine and its subsequent metabolites in plants. However, the importance of SDC and ethanolamine production in plant growth and development remains unclear. Here, we show that SDC is required for ethanolamine biosynthesis in vivo and essential in plant embryogenesis in Arabidopsis. The knockout of SDC1 caused an embryonic lethal defect due to the developmental arrest of the embryos at the heart stage. During embryo development, the expression was observed at the later stages, at which developmental defect occurred in the knockout mutant. Overexpression of SDC1 in planta increased levels of ethanolamine, phosphatidylethanolamine, and phosphatidylcholine both in leaves and siliques. These results suggest that SDC1 plays an essential role in ethanolamine biosynthesis during the embryogenesis in Arabidopsis.

  14. Conservation of proteo-lipid nuclear membrane fusion machinery during early embryogenesis.

    Science.gov (United States)

    Byrne, Richard D; Veeriah, Selvaraju; Applebee, Christopher J; Larijani, Banafshé

    2014-01-01

    The fusogenic lipid diacylglycerol is essential for remodeling gamete and zygote nuclear envelopes (NE) during early embryogenesis. It is unclear whether upstream signaling molecules are likewise conserved. Here we demonstrate PLCγ and its activator SFK1, which co-operate during male pronuclear envelope formation, also promote the subsequent male and female pronuclear fusion. PLCγ and SFK1 interact directly at the fusion site leading to PLCγ activation. This is accompanied by a spatially restricted reduction of PtdIns(4,5)P2. Consequently, pronuclear fusion is blocked by PLCγ or SFK1 inhibition. These findings identify new regulators of events in the early embryo and suggest a conserved "toolkit" of fusion machinery drives successive NE fusion events during embryogenesis.

  15. An important developmental role for oligosaccharides during early embryogenesis of cyprinid fish.

    Science.gov (United States)

    Bakkers, J; Semino, C E; Stroband, H; Kijne, J W; Robbins, P W; Spaink, H P

    1997-07-22

    Derivatives of chitin oligosaccharides have been shown to play a role in plant organogenesis at nanomolar concentrations. Here we present data which indicate that chitin oligosaccharides are important for embryogenesis in vertebrates. We characterize chitin oligosaccharides synthesized in vitro by zebrafish and carp embryos in the late gastrulation stage by incorporation of radiolabeled N-acetyl-D-[U14C]glucosamine and by HPLC in combination with enzymatic conversion using the Bradyrhizobium NodZ alpha-1, 6-fucosyltransferase and chitinases. A rapid and sensitive bioassay for chitin oligosaccharides was also used employing suspension-cultured plant cells of Catharanthus roseus. We show that chitin oligosaccharide synthase activity is apparent only during late gastrulation and can be inhibited by antiserum raised against the Xenopus DG42 protein. The DG42 protein, a glycosyltransferase, is transiently expressed between midblastula and neurulation in Xenopus and zebrafish embryogenesis. Microinjection of the DG42 antiserum or the Bradyrhizobium NodZ enzyme in fertilized eggs of zebrafish led to severe defects in trunk and tail development.

  16. Optimization of embryogenic-callus induction and embryogenesis of ...

    African Journals Online (AJOL)

    ONOS

    2010-09-06

    Sep 6, 2010 ... With the protocol reported herein, some green embryo-like cultures were ... glabra L., callus induction, embryogenesis, cell culture, histological section. .... All experiments were arranged in a completely randomized design.

  17. Identification of expressed sequences in the coffee genome potentially associated with somatic embryogenesis.

    Science.gov (United States)

    Silva, A T; Paiva, L V; Andrade, A C; Barduche, D

    2013-05-21

    Brazil possesses the most modern and productive coffee growing farms in the world, but technological development is desired to cope with the increasing world demand. One way to increase Brazilian coffee growing productivity is wide scale production of clones with superior genotypes, which can be obtained with in vitro propagation technique, or from tissue culture. These procedures can generate thousands of clones. However, the methodologies for in vitro cultivation are genotype-dependent, which leads to an almost empirical development of specific protocols for each species. Therefore, molecular markers linked to the biochemical events of somatic embryogenesis would greatly facilitate the development of such protocols. In this context, sequences potentially involved in embryogenesis processes in the coffee plant were identified in silico from libraries generated by the Brazilian Coffee Genome Project. Through these in silico analyses, we identified 15 EST-contigs related to the embryogenesis process. Among these, 5 EST-contigs (3605, 9850, 13686, 17240, and 17265) could readily be associated with plant embryogenesis. Sequence analysis of EST-contig 3605, 9850, and 17265 revealed similarity to a polygalacturonase, to a cysteine-proteinase, and to an allergenine, respectively. Results also show that EST-contig 17265 sequences presented similarity to an expansin. Finally, analysis of EST-contig 17240 revealed similarity to a protein of unknown function, but it grouped in the similarity dendrogram with the WUSCHEL transcription factor. The data suggest that these EST-contigs are related to the embryogenic process and have potential as molecular markers to increase methodological efficiency in obtaining coffee plant embryogenic materials.

  18. REGENERATION OF Pimpinella pruatjan THROUGH SOMATIC EMBRYOGENESIS

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    I. Roostika

    2016-10-01

    Full Text Available Pruatjan (Pimpinella pruatjan Molk. is an Indonesian endangered plant which has various medicinal properties such as aphrodisiac, diuretic, and tonic. The plant is commonly harvested from its natural habitat, therefore it becomes endangered. Regeneration of pruatjan through organogenesis has been studied, but its shoot multiplication was very low (5 shoots per explant. The study aimed to investigate the best regeneration technique of pruatjan through somatic embryogenesis. This research was conducted at the tissue culture laboratory, Indonesian Center for Agricultural Biotechnology and Genetic Resources Research and Development in 2004-2005. Callus formation of pruatjan was induced from the petioles and leaves in Driver and Kuniyaki’s (DKW based medium containing 2,4-D combined with picloram at the level of 0.5, 1.0, 1.5, and 1.5 ppm. Embryogenic calli were then transferred into embryo development medium in two ways. First, they were directly transferred into media containing IBA/NAA at the level of 0.5, 1.0, and 1.5 ppm. Second, they were indirectly transferred into media containing 2.0 ppm 2,4-D and 0.3% casein hydrolysate prior to the IBA/ NAA media. Parameters evaluated were fresh weight, dry weight, time initiation of embryogenic callus formation, and total number of embryos. The result showed that calli of pruatjan were successfully induced from the petioles and leaves. The best calli were induced from the leaves in the DKW medium containing 2.0 ppm 2,4-D and 0.5 ppm picloram. Embryo development of the calli was best if they were first grown in the media containing 2.0 ppm 2,4-D and 0.3% casein hydrolysate then transferred to the IBA/NAA media. The total number of somatic embryos was counted up to 103 on the medium containing 1.5 ppm IBA. This study indicated that pruatjan somatic embryogenesis regeneration required three different media, i.e. for callus induction, development and maturation, and for

  19. Rape embryogenesis. II. Development of embryo proper

    Directory of Open Access Journals (Sweden)

    Teresa Tykarska

    2015-05-01

    Full Text Available It was found in the continued studies on rape embryogenesis, started by the description of the proembryo (Tykarska, 1976 that the development of embryo is extremely regular and based on differentiating divisions. It appeared that the transverse segmentation boundary and cell walls separating the mother cells of the histogens in the proembryo can be distinguished in all the later stages of the embryo. The border between the cytoledons and epicotyl part of the embryonal axis, and the hypocotyl corresponds to the segmentation boundary between layer l and layer l' at the octant stage. As border between the hypocotyl and radicle was assumed the upper boundary of the root cap reaching usually to the level of the boundary between segments II and III of dermatogen and periblem. The apical meristem of the shoot forms from dermatogen and the periaxial cells of the globular embryo subepidermis. The promeristem of the radicle constists of 3 layers of initial cells surrounding on all sides the inactive layer of central binding cells.

  20. Embryogenesis of bladder exstrophy: A new hypothesis

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    Kulkarni Bharati

    2008-01-01

    Full Text Available Aims and Objective: To postulate a hypothesis to explain the embryogenesis of exstrophy bladder based on our clinical observations. Materials and Methods: In 27 cases of exstrophy, we measured the distance between the lowermost inguinal skin crease to the root of the penis (clitoris (B and the distance between the penis (clitoris and the scrotum (labia majora (C. These were compared with age, height and XP distance (distance between xiphisternum and symphysis pubis matched control group of normal children. The distance between the lowermost inguinal skin crease and the penis (clitoris (A was measured in control group. Results: The observation was A = B + C. This implies that in exstrophy bladder, the position of the penis (clitoris has moved cephalad from the lower border of A to the junction of B and C. Conclusion: Based on the observations, we postulate that abnormal origin of genital tubercle may be the cause of exstrophy bladder. The abnormal origin of primordia of the genital tubercle in more cephalad direction than normal causes wedge effect, which will interfere with the medial migration of the mesoderm as well as the midline approximation of mesodermal structures in the lower abdominal wall, thereby resulting in the exstrophy of bladder.

  1. Gene expression throughout a vertebrate's embryogenesis

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    Hinton David E

    2011-02-01

    Full Text Available Abstract Background Describing the patterns of gene expression during embryonic development has broadened our understanding of the processes and patterns that define morphogenesis. Yet gene expression patterns have not been described throughout vertebrate embryogenesis. This study presents statistical analyses of gene expression during all 40 developmental stages in the teleost Fundulus heteroclitus using four biological replicates per stage. Results Patterns of gene expression for 7,000 genes appear to be important as they recapitulate developmental timing. Among the 45% of genes with significant expression differences between pairs of temporally adjacent stages, significant differences in gene expression vary from as few as five to more than 660. Five adjacent stages have disproportionately more significant changes in gene expression (> 200 genes relative to other stages: four to eight and eight to sixteen cell stages, onset of circulation, pre and post-hatch, and during complete yolk absorption. The fewest differences among adjacent stages occur during gastrulation. Yet, at stage 16, (pre-mid-gastrulation the largest number of genes has peak expression. This stage has an over representation of genes in oxidative respiration and protein expression (ribosomes, translational genes and proteases. Unexpectedly, among all ribosomal genes, both strong positive and negative correlations occur. Similar correlated patterns of expression occur among all significant genes. Conclusions These data provide statistical support for the temporal dynamics of developmental gene expression during all stages of vertebrate development.

  2. Requirement of SLD5 for early embryogenesis.

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    Tomomi Mohri

    Full Text Available SLD5 forms a GINS complex with PSF1, PSF2 and PSF3, which is essential for the initiation of DNA replication in lower eukaryotes. Although these components are conserved in mammals, their biological function is unclear. We show here that targeted disruption of SLD5 in mice causes a defect in cell proliferation in the inner cell mass, resulting in embryonic lethality at the peri-implantation stage, indicating that SLD5 is essential for embryogenesis. Moreover, this phenotype of SLD5 mutant mice is quite similar compared with that of PSF1 mutant mice. We have previously reported that haploinsufficiency of PSF1 resulted in failure of acute proliferation of bone marrow hematopoietic stem cells (HSCs during reconstitution of bone marrow ablated by 5-FU treatment. Since SLD5 was highly expressed in bone marrow, we investigated its involvement in bone marrow reconstitution after bone marrow ablation as observed in PSF1 heterozygous mutant mice. However, heterozygous deletion of the SLD5 gene was found not to significantly affect bone marrow reconstitution. On the other hand, abundant SLD5 expression was observed in human cancer cell lines and heterozygous deletion of the gene attenuated tumor progression in a murine model of spontaneous gastric cancer. These indicated that requirement and dependency of SLD5 for cell proliferation is different in different cell types.

  3. Acrolein and embryogenesis: an experimental study

    Energy Technology Data Exchange (ETDEWEB)

    Chhibber, G.; Cilani, S.H.

    1986-01-01

    The effects of acrolein were studied on the chick embryos of 48 and 72 hr of incubation. Acrolein was dissolved in physiological saline and injected into the air sacs of the eggs at doses ranging from 0.001 to 0.1 mg per egg. The controls received and equal amount of saline only (0.1 ml per egg). All the embryos including controls were examined at Day 13. In all, 600 eggs were utilized for this investigation. At 48 hr incubation, the percentage survival ranged from 80 to 0 as the dosage of acrolein was increased. Embryonic mortality following 72 hr incubation did not increase significantly at any dose level. Gross malformations such as short and twisted limbs, everted viscera, microphthalmia, short and twisted neck, and hemorrhage over the body were observed. The frequency and the types of gross abnormalities did not vary much in the 48- or 72-hr-treated groups. The incidence of malformation in the controls was low. The results of this study indicates that acrolein is embryotoxic at higher doses and moderately teratogenic to chick embryogenesis.

  4. Comparative proteomic analysis of early somatic and zygotic embryogenesis in Theobroma cacao L.

    Science.gov (United States)

    Noah, Alexandre Mboene; Niemenak, Nicolas; Sunderhaus, Stephanie; Haase, Christin; Omokolo, Denis Ndoumou; Winkelmann, Traud; Braun, Hans-Peter

    2013-01-14

    Somatic embryogenesis can efficiently foster the propagation of Theobroma cacao, but the poor quality of resulted plantlet hinders the use of this technique in the commercial scale. The current study has been initiated to systematically compare the physiological mechanisms underlying somatic and zygotic embryogenesis in T. cacao on the proteome level. About 1000 protein spots per fraction could be separated by two-dimensional isoelectric focusing/SDS PAGE. More than 50 of the protein spots clearly differed in abundance between zygotic and somatic embryos: 33 proteins spots were at least 3-fold higher in abundance in zygotic embryos and 20 in somatic embryos. Analyses of these protein spots differing in volume by mass spectrometry resulted in the identification of 68 distinct proteins. Many of the identified proteins are involved in genetic information processing (21 proteins), carbohydrate metabolism (11 proteins) and stress response (7 proteins). Somatic embryos especially displayed many stress related proteins, few enzymes involved in storage compound synthesis and an exceptional high abundance of endopeptidase inhibitors. Phosphoenolpyruvate carboxylase, which was accumulated more than 3-fold higher in zygotic embryos, represents a prominent enzyme in the storage compound metabolism in cacao seeds. Implications on the improvement of somatic embryogenesis in cacao are discussed. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Essential role of the TFIID subunit TAF4 in murine embryogenesis and embryonic stem cell differentiation.

    Science.gov (United States)

    Langer, Diana; Martianov, Igor; Alpern, Daniel; Rhinn, Muriel; Keime, Céline; Dollé, Pascal; Mengus, Gabrielle; Davidson, Irwin

    2016-03-30

    TAF4 (TATA-binding protein-associated factor 4) and its paralogue TAF4b are components of the TFIID core module. We inactivated the murine Taf4a gene to address Taf4 function during embryogenesis. Here we show that Taf4a(-/-) embryos survive until E9.5 where primary germ layers and many embryonic structures are identified showing Taf4 is dispensable for their specification. In contrast, Taf4 is required for correct patterning of the trunk and anterior structures, ventral morphogenesis and proper heart positioning. Overlapping expression of Taf4a and Taf4b during embryogenesis suggests their redundancy at early stages. In agreement with this, Taf4a(-/-) embryonic stem cells (ESCs) are viable and comprise Taf4b-containing TFIID. Nevertheless, Taf4a(-/-) ESCs do not complete differentiation into glutamatergic neurons and cardiomyocytes in vitro due to impaired preinitiation complex formation at the promoters of critical differentiation genes. We define an essential role of a core TFIID TAF in differentiation events during mammalian embryogenesis.

  6. TRAUCO, a Trithorax-group gene homologue, is required for early embryogenesis in Arabidopsis thaliana.

    Science.gov (United States)

    Aquea, Felipe; Johnston, Amal J; Cañon, Paola; Grossniklaus, Ueli; Arce-Johnson, Patricio

    2010-02-01

    Embryogenesis is a critical stage during the plant life cycle in which a unicellular zygote develops into a multicellular organism. Co-ordinated gene expression is thus necessary for proper embryo development. Polycomb and Trithorax group genes are members of evolutionarily conserved machinery that maintains the correct expression patterns of key developmental regulators by repressing and activating gene transcription. TRAUCO (TRO), a gene homologous to the Trithorax group of genes that can functionally complement a BRE2P yeast mutant, has been identified in Arabidopsis thaliana. It is demonstrated that TRO is a nuclear gene product expressed during embryogenesis, and loss of TRO function leads to impaired early embryo development. Embryos that arrested at the globular stage in the tro-1 mutant allele were fully rescued by a TRO expression clone, a demonstration that the tro-1 mutation is a true loss-of-function in TRO. Our data have established that TRO is the first trithorax-group gene homologue in plants that is required for early embryogenesis.

  7. [The biological clock in vertebrate embryogenesis as a mechanism of general control over the developmental organism].

    Science.gov (United States)

    Gorodilov, Iu N

    2010-01-01

    The problem of understanding the role of the time factor in embryogenesis is still at the conceptual stage. At the same time, a number of rhythmic processes described in the embryogenesis of animals point to the involvement of a biological clock in this period of ontogenesis. Most of them (biochemical, biophysical, cytological) have been identified during the process of cleavage and have a duration equal to that of a single cleavage division tau0. The current paper considers mainly the development of salmon fish embryos, which, in comparison with the widely used models (Danio rerio, Orysias latipes), have some extra advantages: they are about twice as big at similar stages and develop 30-40 times slower. The most pronounced and rhythmical process in vertebrates is somitogenesis. The work presents a series of fundamental facts in relation to the temporal and spatial aspects of somitogenesis: 1) the formation of each new somite occurs within a constant time tauS; 2) this time is controlled to a high degree of accuracy; 3) the size of new somites (l(S)) along the anterioposterior axis is constant; 4) the temporal factor, in contrast to the spatial, plays the primary role during morphogenesis of somites. The rhythms tau0 and taoS in different species are equal or are multiples of each other, an indication of their common origin. A high degree of synchronism in embryo development from the start of cleavage to the end ofsomitogenesis is revealed. This proves the existence of constant temporal control of their development during most of the period of embryogenesis. It is proposed that the endogenic rhythms under discussion are responsible for the coordination and integration of multilevel processes in embryogenesis, compensating for the lack of a formed nervous system during this period.

  8. Combining the least cost path method with population genetic data and species distribution models to identify landscape connectivity during the late Quaternary in Himalayan hemlock.

    Science.gov (United States)

    Yu, Haibin; Zhang, Yili; Liu, Linshan; Qi, Wei; Li, Shicheng; Hu, Zhongjun

    2015-12-01

    Himalayan hemlock (Tsuga dumosa) experienced a recolonization event during the Quaternary period; however, the specific dispersal routes are remain unknown. Recently, the least cost path (LCP) calculation coupled with population genetic data and species distribution models has been applied to reveal the landscape connectivity. In this study, we utilized the categorical LCP method, combining species distribution of three periods (the last interglacial, the last glacial maximum, and the current period) and locality with shared chloroplast, mitochondrial, and nuclear haplotypes, to identify the possible dispersal routes of T. dumosa in the late Quaternary. Then, both a coalescent estimate of migration rates among regional groups and establishment of genetic divergence pattern were conducted. After those analyses, we found that the species generally migrated along the southern slope of Himalaya across time periods and genomic makers, and higher degree of dispersal was in the present and mtDNA haplotype. Furthermore, the direction of range shifts and strong level of gene flow also imply the existence of Himalayan dispersal path, and low area of genetic divergence pattern suggests that there are not any obvious barriers against the dispersal pathway. Above all, we inferred that a dispersal route along the Himalaya Mountains could exist, which is an important supplement for the evolutionary history of T. dumosa. Finally, we believed that this integrative genetic and geospatial method would bring new implications for the evolutionary process and conservation priority of species in the Tibetan Plateau.

  9. Quantitative Glycoproteomic Analysis Identifies Platelet-Induced Increase of Monocyte Adhesion via the Up-Regulation of Very Late Antigen 5.

    Science.gov (United States)

    Huang, Jiqing; Kast, Juergen

    2015-08-07

    Physiological stimuli, such as thrombin, or pathological stimuli, such as lysophosphatidic acid (LPA), activate platelets circulating in blood. Once activated, platelets bind to monocytes via P-selectin-PSGL-1 interactions but also release the stored contents of their granules. These platelet releasates, in addition to direct platelet binding, activate monocytes and facilitate their recruitment to atherosclerotic sites. Consequently, understanding the changes platelet releasates induce in monocyte membrane proteins is critical. We studied the glyco-proteome changes of THP-1 monocytic cells affected by LPA- or thrombin-induced platelet releasates. We employed lectin affinity chromatography combined with filter aided sample preparation to achieve high glyco- and membrane protein and protein sequence coverage. Using stable isotope labeling by amino acids in cell culture, we quantified 1715 proteins, including 852 membrane and 500 glycoproteins, identifying the up-regulation of multiple proteins involved in monocyte extracellular matrix binding and transendothelial migration. Flow cytometry indicated expression changes of integrin α5, integrin β1, PECAM-1, and PSGL-1. The observed increase in monocyte adhesion to fibronectin was determined to be mediated by the up-regulation of very late antigen 5 via a P-selectin-PSGL-1 independent mechanism. This novel aspect could be validated on CD14+ human primary monocytes, highlighting the benefits of the improved enrichment method regarding high membrane protein coverage and reliable quantification.

  10. Expression patterns of LmAP2L1 and LmAP2L2 encoding two-APETALA2 domain proteins during somatic embryogenesis and germination of hybrid larch (Larix x marschlinsii).

    Science.gov (United States)

    Guillaumot, Damien; Lelu-Walter, Marie-Anne; Germot, Agnès; Meytraud, Fanny; Gastinel, Louis; Riou-Khamlichi, Catherine

    2008-06-16

    Two APETALA2 domain transcription factors were characterized first in angiosperms, and, recently, in several gymnosperms. These proteins are involved in several processes, from flowering to embryogenesis in Arabidopsis thaliana. We extrapolated this result to hybrid larch (Larixxmarschlinsii Coaz) resulting from a cross between European (Larix decidua) and Japanese (Larix kaempferi) larches. Somatic embryogenesis is well described and controlled for this Pinaceae. We characterized two-AP2 domain genes: LmAP2L1 and LmAP2L2. Phylogenetic analysis confirmed that LmAP2L1 and LmAP2L2 were orthologous to Norway spruce PaAP2L1 and PaAP2L2 and that L1 forms appeared to be specific to Pinaceae. RT-PCR analysis showed that larch APETALA2 was differentially expressed during late somatic embryogenesis and during the first steps of germination. Whereas LmAP2L2 was constitutively expressed during this process, LmAP2L1 expression appeared only during late somatic embryogenesis, when embryos were able to germinate. Further, LmAP2L1 appeared to be the preferentially expressed form during embryo germination. Thus, LmAP2L1 seems to be a valuable molecular marker for hybrid larch late somatic embryogenesis and could play a role during post-embryonic development.

  11. GWAS-identified risk variants for major depressive disorder: Preliminary support for an association with late-life depressive symptoms and brain structural alterations.

    Science.gov (United States)

    Ryan, Joanne; Artero, Sylvaine; Carrière, Isabelle; Maller, Jerome J; Meslin, Chantal; Ritchie, Karen; Ancelin, Marie-Laure

    2016-01-01

    A number of genome-wide association studies (GWAS) have investigated risk factors for major depressive disorder (MDD), however there has been little attempt to replicate these findings in population-based studies of depressive symptoms. Variants within three genes, BICC1, PCLO and GRM7 were selected for replication in our study based on the following criteria: they were identified in a prior MDD GWAS study; a subsequent study found evidence that they influenced depression risk; and there is a solid biological basis for a role in depression. We firstly investigated whether these variants were associated with depressive symptoms in our population-based cohort of 929 elderly (238 with clinical depressive symptoms and 691 controls), and secondly to investigate associations with structural brain alterations. A number of nominally significant associations were identified, but none reached Bonferroni-corrected significance levels. Common SNPs in BICC1 and PCLO were associated with a 50% and 30% decreased risk of depression, respectively. PCLO rs2522833 was also associated with the volume of grey matter (p=1.6×10(-3)), and to a lesser extent with hippocampal volume and white matter lesions. Among depressed individuals rs9870680 (GRM7) was associated with the volume of grey and white matter (p=10(-4) and 8.3×10(-3), respectively). Our results provide some support for the involvement of BICC1 and PCLO in late-life depressive disorders and preliminary evidence that these genetic variants may also influence brain structural volumes. However effect sizes remain modest and associations did not reach corrected significance levels. Further large imaging studies are needed to confirm our findings.

  12. Proteomic identification of differentially expressed proteins during the acquisition of somatic embryogenesis in oil palm (Elaeis guineensis Jacq.).

    Science.gov (United States)

    Silva, Rafael de Carvalho; Carmo, Lilian Silveira Travassos; Luis, Zanderluce Gomes; Silva, Luciano Paulino; Scherwinski-Pereira, Jonny Everson; Mehta, Angela

    2014-06-02

    In the present study we have identified and characterized the proteins expressed during different developmental stages of Elaeis guineensis calli obtained from zygotic embryos. We were interested in the possible proteomic changes that would occur during the acquisition of somatic embryogenesis and therefore samples were collected from zygotic embryos (E1), swollen explants 14days (E2) in induction medium, primary callus (E3), and pro-embryogenic callus (E4). The samples were grinded in liquid nitrogen, followed by total protein extraction using phenol and extraction buffer. Proteins were analyzed by two-dimensional electrophoresis (2-DE) and the differentially expressed protein spots were analyzed by MALDI-TOF mass spectrometry (MS and MS/MS). Interestingly, we have identified proteins, which can be used as potential candidates for future studies aiming at the development of biomarkers for embryogenesis acquisition and for the different stages leading to pro-embryogenic callus formation such as type IIIa membrane protein cp-wap13, fructokinase and PR proteins. The results obtained shed some light on the biochemical events involved in the process of somatic embryogenesis of E. guineensis obtained from zygotic embryos. The use of stage-specific protein markers can help monitor cell differentiation and contribute to improve the protocols for successfully cloning the species. Understanding the fate and dynamics of cells and tissues during callus formation is essential to understand totipotency and the mechanisms involved during acquisition of somatic embryogenesis (SE). In this study we have investigated the early stages of somatic embryogenesis induction in oil palm and have identified potential markers as well as proteins potentially involved in embryogenic competence acquisition. The use of these proteins can help improve tissue culture protocols in order to increase regeneration rates. This article is part of a Special Issue entitled: Environmental and structural

  13. Somatic Embryogenesis in Four Tree Legumes

    Directory of Open Access Journals (Sweden)

    Premananda Das

    2011-01-01

    Full Text Available Somatic embryogenesis was achieved in four leguminous tree species, that is, Acacia catechu, Acacia arabica, Hardwickia binata, and Dalbergia sissoo using immature zygotic embryos as explants on Murashige and Skoog (MS medium supplemented with 0.25–1.0 mg/l Kn (kinetin and 2.0–3.0 mg/l 2,4-D (2,4-dichlorophenoxyacetic acid or NAA (1-napthaleneacetic acid and 3% sucrose. MS medium containing 2.0 mg/l 2,4-D and 1.0–1.5 mg/l Kn was noted to be most effective in inducing friable embryogenic callus (FEC; the number of somatic embryos per culture varied in MS medium supplemented with 1.0–2.0 mg/l 2,4-D or NAA and 0.25–1.5 mg/l kinetin. The maximum number of somatic embryos was obtained in MS medium containing 1.5–2.0 mg/l 2,4-D or NAA and 1.0–1.5 mg/l kinetin; proliferation of embryogenic calli was enhanced in cultures having 1.0–2.0 mg/l 2,4-D, 1.0–1.5 mg/l kinetin, and 400–600 mg/l L-Proline. The somatic embryos in various shapes and sizes after the first subculture on MS medium supplemented with 0.1 mg/l IAA and 0.25 mg/l BA; developed shoots and rooted in 1/2 strength MS medium supplemented with 0.1 mg/l IBA or IAA. The somatic embryo-derived plantlets were transferred to the field after being hardened in the climate-controlled hardening chamber.

  14. Embryogenesis and larval biology of the cold-water coral Lophelia pertusa.

    Directory of Open Access Journals (Sweden)

    Ann I Larsson

    Full Text Available Cold-water coral reefs form spectacular and highly diverse ecosystems in the deep sea but little is known about reproduction, and virtually nothing about the larval biology in these corals. This study is based on data from two locations of the North East Atlantic and documents the first observations of embryogenesis and larval development in Lophelia pertusa, the most common framework-building cold-water scleractinian. Embryos developed in a more or less organized radial cleavage pattern from ∼ 160 µm large neutral or negatively buoyant eggs, to 120-270 µm long ciliated planulae. Embryogenesis was slow with cleavage occurring at intervals of 6-8 hours up to the 64-cell stage. Genetically characterized larvae were sexually derived, with maternal and paternal alleles present. Larvae were active swimmers (0.5 mm s(-1 initially residing in the upper part of the water column, with bottom probing behavior starting 3-5 weeks after fertilization. Nematocysts had developed by day 30, coinciding with peak bottom-probing behavior, and possibly an indication that larvae are fully competent to settle at this time. Planulae survived for eight weeks under laboratory conditions, and preliminary results indicate that these planulae are planktotrophic. The late onset of competency and larval longevity suggests a high dispersal potential. Understanding larval biology and behavior is of paramount importance for biophysical modeling of larval dispersal, which forms the basis for predictions of connectivity among populations.

  15. DNA methylation during sexual embryogenesis and implications on the induction of somatic embryogenesis in Castanea sativa Miller.

    Science.gov (United States)

    Viejo, M; Rodríguez, R; Valledor, L; Pérez, M; Cañal, M J; Hasbún, R

    2010-12-01

    From anthesis to mature seed formation, burrs from cross-pollinated adult Castanea sativa Miller trees were characterized and seven developmental stages defined based on macro and micromorphological traits. In order to get an insight into the involvement of epigenetic mechanisms in sexual embryogenesis and to define somatic embryogenesis induction capability, global DNA methylation and the somatic embryogenic competence were quantified. On cross-pollinated trees once fertilization takes place, at least one ovule per ovary becomes dominant, and transient DNA demethylation occurs coinciding with the start of the sexual embryogenic programme. Unfertilized ovules from the same cluster, which maintain their prior size, increase their methylation level and undergo degeneration. These results were validated using non-cross-pollinated trees and the asynchrony of flower receptivity. When testing in vitro somatic embryogenesis response of isolated dominant ovules and axes from zygotic embryos under cross-pollinated conditions, the highest competence was found for reaching seed maturity. Thus, a "developmental window" of somatic embryogenesis in chestnut has been characterized. It includes from fertilization to embryo maturity, and a transient decrease in methylation is necessary after fertilization for the development of the somatic embryogenesis response.

  16. Somatic Embryogenesis: Still a Relevant Technique in Citrus Improvement.

    Science.gov (United States)

    Omar, Ahmad A; Dutt, Manjul; Gmitter, Frederick G; Grosser, Jude W

    2016-01-01

    The genus Citrus contains numerous fresh and processed fruit cultivars that are economically important worldwide. New cultivars are needed to battle industry threatening diseases and to create new marketing opportunities. Citrus improvement by conventional methods alone has many limitations that can be overcome by applications of emerging biotechnologies, generally requiring cell to plant regeneration. Many citrus genotypes are amenable to somatic embryogenesis, which became a key regeneration pathway in many experimental approaches to cultivar improvement. This chapter provides a brief history of plant somatic embryogenesis with focus on citrus, followed by a discussion of proven applications in biotechnology-facilitated citrus improvement techniques, such as somatic hybridization, somatic cybridization, genetic transformation, and the exploitation of somaclonal variation. Finally, two important new protocols that feature plant regeneration via somatic embryogenesis are provided: protoplast transformation and Agrobacterium-mediated transformation of embryogenic cell suspension cultures.

  17. Consistency of polyamine profiles and expression of arginine decarboxylase in mitosis during zygotic embryogenesis of Scots pine.

    Science.gov (United States)

    Vuosku, Jaana; Jokela, Anne; Läärä, Esa; Sääskilahti, Mira; Muilu, Riina; Sutela, Suvi; Altabella, Teresa; Sarjala, Tytti; Häggman, Hely

    2006-11-01

    In this study, we show that both arginine decarboxylase (ADC) protein and mRNA transcript are present at different phases of mitosis in Scots pine (Pinus sylvestris) zygotic embryogenesis. We also examined the consistency of polyamine (PA) profiles with the effective temperature sum, the latter indicating the developmental stage of the embryos. PA metabolism was analyzed by fitting statistical regression models to the data of free and soluble conjugated PAs, to the enzyme activities of ADC and ornithine decarboxylase (ODC), as well as to the gene expression of ADC. According to the fitted models, PAs typically had the tendency to increase at the early stages but decrease at the late stages of embryogenesis. Only the free putrescine fraction remained stable during embryo development. The PA biosynthesis strongly preferred the ADC pathway. Both ADC gene expression and ADC enzyme activity were substantially higher than putative ODC gene expression or ODC enzyme activity, respectively. ADC gene expression and enzyme activity increased during embryogenesis, which suggests the involvement of transcriptional regulation in the expression of ADC. Both ADC mRNA and ADC protein localized in dividing cells of embryo meristems and more specifically within the mitotic spindle apparatus and close to the chromosomes, respectively. The results suggest the essential role of ADC in the mitosis of plant cells.

  18. Early plant embryogenesis-dark ages or dark matter?

    Science.gov (United States)

    Bayer, Martin; Slane, Daniel; Jürgens, Gerd

    2017-02-01

    In nearly all flowering plants, the basic body plan is laid down during embryogenesis. In Arabidopsis, the crucial cell types are established extremely early as reflected in the stereotypic sequence of oriented cell divisions in the developing young embryo. Research into early embryogenesis was especially focused on the role of the infamous tryptophan derivative auxin in establishing embryo polarity and generating the main body axis. However, it is becoming obvious that the mere link to auxin does not provide any mechanistic understanding of early embryo patterning. Taking recent research into account, we discuss mechanisms underlying early embryonic patterning from an evolutionary perspective.

  19. Isolation of carrot Argonaute1 from subtractive somatic embryogenesis cDNA library.

    Science.gov (United States)

    Takahata, Kiminori

    2008-03-01

    Carrot Argonaute1 (C-Ago1) was isolated from a subtractive cDNA library to obtain somatic embryogenesis related genes. C-Ago1 has three conserved domains, which are found in all other Argonautes. C-Ago1 has specific expression during somatic embryogenesis, which indicates that microRNA gene expression controlling system is required for somatic embryogenesis.

  20. Isolation of Polysaccharides Sulfated during Early Embryogenesis in Fucus.

    Science.gov (United States)

    Hogsett, W E; Quatrano, R S

    1975-01-01

    Beginning 10 hours after fertilization, zygotes of Fucus distichus L. Powell incorporate (35)S into polysaccharides as a sulfate ester of fucose. These sulfated polysaccharides are sequestered in only the rhizoid cell of the two-celled embryo and can serve as a marker of cellular differentiation. Zygotes were pulsed at different times after fertilization with Na(2) (35)SO(4) to identify and isolate the fucans localized within the region of cytoplasm destined to become the rhizoid cell. Low molecular weight pools of (35)S were saturated within 60 minutes, with the greatest incorporation into ethanol-soluble and insoluble fractions occurring with 0.1 mm Na(2)SO(4) in the artificial sea water medium. At the time of rhizoid formation, four fucose-containing polysaccharide fractions incorporated (35)S. When each fraction was subjected to diethylaminoethyl chromatography, two components were eluted with KCl that contained over 84% of the fucose and 93% of the (35)S of the particular fraction. Highvoltage paper electrophoresis of each fraction also resulted in the separation of these two major components. Both components from each of the four fractions behaved identically when separated by diethylaminoethyl chromatography and paper electrophoresis. By comparing the incorporation of (35)S into the polysaccharide fractions at 4 and 16 hours after fertilization, the fucan-sulfate components that are localized in the cytoplasm at the time of rhizoid formation were isolated. Although sulfated polysaccharides in brown algae are reported to be very heterogeneous in terms of their sugar composition and complexes with other heteropolymers, we propose that there are two major components that are sulfated during early embryogenesis in Fucus. The location of these two sulfated polysaccharides in different chemical fractions may reflect their subcellular localization (e.g., cytoplasmic vesicles or cell walls), or their association with other heteropolymers.

  1. Developmental origins of neurotransmitter and transcriptome alterations in adult female zebrafish exposed to atrazine during embryogenesis.

    Science.gov (United States)

    Wirbisky, Sara E; Weber, Gregory J; Sepúlveda, Maria S; Xiao, Changhe; Cannon, Jason R; Freeman, Jennifer L

    2015-07-03

    Atrazine is an herbicide applied to agricultural crops and is indicated to be an endocrine disruptor. Atrazine is frequently found to contaminate potable water supplies above the maximum contaminant level of 3μg/L as defined by the U.S. Environmental Protection Agency. The developmental origin of adult disease hypothesis suggests that toxicant exposure during development can increase the risk of certain diseases during adulthood. However, the molecular mechanisms underlying disease progression are still unknown. In this study, zebrafish embryos were exposed to 0, 0.3, 3, or 30μg/L atrazine throughout embryogenesis. Larvae were then allowed to mature under normal laboratory conditions with no further chemical treatment until 7 days post fertilization (dpf) or adulthood and neurotransmitter analysis completed. No significant alterations in neurotransmitter levels was observed at 7dpf or in adult males, but a significant decrease in 5-hydroxyindoleacetic acid (5-HIAA) and serotonin turnover was seen in adult female brain tissue. Transcriptomic analysis was completed on adult female brain tissue to identify molecular pathways underlying the observed neurological alterations. Altered expression of 1928, 89, and 435 genes in the females exposed to 0.3, 3, or 30μg/L atrazine during embryogenesis were identified, respectively. There was a high level of overlap between the biological processes and molecular pathways in which the altered genes were associated. Moreover, a subset of genes was down regulated throughout the serotonergic pathway. These results provide support of the developmental origins of neurological alterations observed in adult female zebrafish exposed to atrazine during embryogenesis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  2. Somatic Embryogenesis of Lilium from Microbulb Transverse Thin Cell Layers.

    Science.gov (United States)

    Marinangeli, Pablo

    2016-01-01

    A reliable somatic embryogenesis protocol is a prerequisite for application of other plant biotechniques. Several protocols were reported for genus Lilium, with variable success. Between them, transverse Thin Cell Layers (tTCL) were used efficiently to induce indirect somatic embryogenesis of Lilium. Somatic embryogenesis potential is dependent on the genotype, explant, and culture medium composition, especially as for plant growth regulators and environmental conditions. Usually, the process comprises three phases: embryogenic callus induction, embryogenic callus proliferation and somatic embryo germination. Somatic embryo germination can be achieved in light or dark. In the first case, complete plantlets are formed, with green leaves and pseudobulb in the base. In darkness, microbulbs are formed from single somatic embryos or clusters. A last phase of microbulb enlargement allows plantlets or microbulbs to increase their biomass. These enlarged microbulbs do not need special acclimatization conditions when transferred to soil and quickly produce sturdy plants. This chapter describes a protocol for somatic embryogenesis of Lilium using tTCL from microbulbs.

  3. Somatic embryogenesis for efficient micropropagation of guava (Psidium guajava L.).

    Science.gov (United States)

    Akhtar, Nasim

    2013-01-01

    Guava (Psidium guajava L.) is well known for edible fruit, environment friendly pharmaceutical and commercial products for both national and international market. The conventional propagation and in vitro organogenesis do not meet the demand for the good quality planting materials. Somatic embryogenesis for efficient micropropagation of guava (P. guajava L.) has been developed to fill up the gap. Somatic embryogenesis and plantlets regeneration are achieved from 10-week post-anthesis zygotic embryo explants by 8-day inductive treatment with different concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D) on MS agar medium containing 5% sucrose. Subsequent development and maturation of somatic embryos occur after 8 days on MS basal medium supplemented with 5% sucrose without plant growth regulator. The process of somatic embryogenesis shows the highest relative efficiency in 8-day treatment of zygotic embryo explants with 1.0 mg L(-1) 2,4-D. High efficiency germination of somatic embryos and plantlet regeneration takes place on half strength semisolid MS medium amended with 3% sucrose within 2 weeks of subculture. Somatic plantlets are grown for additional 2 weeks by subculturing in MS liquid growth medium containing 3% sucrose. Well-grown plantlets from liquid medium have survived very well following 2-4 week hardening process. The protocol of somatic embryogenesis is optimized for high efficiency micropropagation of guava species.

  4. Induction of plant somatic embryogenesis in liquid medium.

    NARCIS (Netherlands)

    Kreuger, M.

    1996-01-01

    The large scale propagation of plants via somatic embryogenesis, has so far been difficult to achieve. In this thesis research is described leading to embryogenic cell lines that can be maintained for a long period, without loss of genetic stability. It is also described how embryogenic potential of

  5. Induction of plant somatic embryogenesis in liquid medium

    NARCIS (Netherlands)

    Kreuger, M.

    1996-01-01


    The large scale propagation of plants via somatic embryogenesis, has so far been difficult to achieve. In this thesis research is described leading to embryogenic cell lines that can be maintained for a long period, without loss of genetic stability. It is also described how embryogenic

  6. FGF signalling: diverse roles during early vertebrate embryogenesis.

    Science.gov (United States)

    Dorey, Karel; Amaya, Enrique

    2010-11-01

    Fibroblast growth factor (FGF) signalling has been implicated during several phases of early embryogenesis, including the patterning of the embryonic axes, the induction and/or maintenance of several cell lineages and the coordination of morphogenetic movements. Here, we summarise our current understanding of the regulation and roles of FGF signalling during early vertebrate development.

  7. Induction of plant somatic embryogenesis in liquid medium

    NARCIS (Netherlands)

    Kreuger, M.

    1996-01-01


    The large scale propagation of plants via somatic embryogenesis, has so far been difficult to achieve. In this thesis research is described leading to embryogenic cell lines that can be maintained for a long period, without loss of genetic stability. It is also described how embryogenic p

  8. BABY BOOM-induced somatic embryogenesis in Arabidopsis

    NARCIS (Netherlands)

    Horstman, A.

    2015-01-01

    Under appropriate tissue culture conditions, somatic plant cells can be induced to form embryos in a process called somatic embryogenesis (SE). SE provides a way to clonally propagate desirable plants and is therefore an important plant breeding tool. SE has also fascinated scientists for decades as

  9. Drosophila embryogenesis scales uniformly across temperature in developmentally diverse species.

    Directory of Open Access Journals (Sweden)

    Steven G Kuntz

    2014-04-01

    Full Text Available Temperature affects both the timing and outcome of animal development, but the detailed effects of temperature on the progress of early development have been poorly characterized. To determine the impact of temperature on the order and timing of events during Drosophila melanogaster embryogenesis, we used time-lapse imaging to track the progress of embryos from shortly after egg laying through hatching at seven precisely maintained temperatures between 17.5 °C and 32.5 °C. We employed a combination of automated and manual annotation to determine when 36 milestones occurred in each embryo. D. melanogaster embryogenesis takes [Formula: see text]33 hours at 17.5 °C, and accelerates with increasing temperature to a low of 16 hours at 27.5 °C, above which embryogenesis slows slightly. Remarkably, while the total time of embryogenesis varies over two fold, the relative timing of events from cellularization through hatching is constant across temperatures. To further explore the relationship between temperature and embryogenesis, we expanded our analysis to cover ten additional Drosophila species of varying climatic origins. Six of these species, like D. melanogaster, are of tropical origin, and embryogenesis time at different temperatures was similar for them all. D. mojavensis, a sub-tropical fly, develops slower than the tropical species at lower temperatures, while D. virilis, a temperate fly, exhibits slower development at all temperatures. The alpine sister species D. persimilis and D. pseudoobscura develop as rapidly as tropical flies at cooler temperatures, but exhibit diminished acceleration above 22.5 °C and have drastically slowed development by 30 °C. Despite ranging from 13 hours for D. erecta at 30 °C to 46 hours for D. virilis at 17.5 °C, the relative timing of events from cellularization through hatching is constant across all species and temperatures examined here, suggesting the existence of a previously unrecognized timer

  10. Genes encoding novel secreted and transmembrane proteins are temporally and spatially regulated during Drosophila melanogaster embryogenesis

    Directory of Open Access Journals (Sweden)

    González Mauricio

    2009-09-01

    Full Text Available Abstract Background Morphogenetic events that shape the Drosophila melanogaster embryo are tightly controlled by a genetic program in which specific sets of genes are up-regulated. We used a suppressive subtractive hybridization procedure to identify a group of developmentally regulated genes during early stages of D. melanogaster embryogenesis. We studied the spatiotemporal activity of these genes in five different intervals covering 12 stages of embryogenesis. Results Microarrays were constructed to confirm induction of expression and to determine the temporal profile of isolated subtracted cDNAs during embryo development. We identified a set of 118 genes whose expression levels increased significantly in at least one developmental interval compared with a reference interval. Of these genes, 53% had a phenotype and/or molecular function reported in the literature, whereas 47% were essentially uncharacterized. Clustering analysis revealed demarcated transcript groups with maximum gene activity at distinct developmental intervals. In situ hybridization assays were carried out on 23 uncharacterized genes, 15 of which proved to have spatiotemporally restricted expression patterns. Among these 15 uncharacterized genes, 13 were found to encode putative secreted and transmembrane proteins. For three of them we validated our protein sequence predictions by expressing their cDNAs in Drosophila S2R+ cells and analyzed the subcellular distribution of recombinant proteins. We then focused on the functional characterization of the gene CG6234. Inhibition of CG6234 by RNA interference resulted in morphological defects in embryos, suggesting the involvement of this gene in germ band retraction. Conclusion Our data have yielded a list of developmentally regulated D. melanogaster genes and their expression profiles during embryogenesis and provide new information on the spatiotemporal expression patterns of several uncharacterized genes. In particular, we

  11. Effects of High Magneto-Gravitational Environment on Silkworm Embryogenesis

    Science.gov (United States)

    Tian, Zongcheng; Li, Muwang; Qian, Airong; Xu, Huiyun; Wang, Zhe; Di, Shengmeng; Yang, Pengfei; Hu, Lifang; Ding, Chong; Zhang, Wei; Luo, Mingzhi; Han, Jing; Gao, Xiang; Huang, Yongping; Shang, Peng

    2010-04-01

    The objective of this research was to observe whether silkworm embryos can survive in a high magneto-gravitational environment (HMGE) and what significant phenotype changes can be produced. The hatching rate, hatching time, life span, growth velocity and cocoon weight of silkworm were measured after silkworm embryos were exposed to HMGE (0 g, 12 T; 1 g, 16 T; and 2 g, 12 T) for a period of time. Compared with the control group, 0 g exposure resulted in a lower hatching rate and a shorter life span. Statistically insignificant morphological changes had been observed for larvae growth velocity, incidence of abnormal markings and weight of cocoons. These results suggest that the effect of HMGE on silkworm embryogenesis is not lethal. Bio-effects of silkworm embryogenesis at 0 g in a HMGE were similar with those of space flight. The hatching time, life span and hatching rates of silkworm may be potential phenotype markers related to exposure in a weightless environment.

  12. Somatic Embryogenesis in Two Orchid Genera (Cymbidium, Dendrobium).

    Science.gov (United States)

    da Silva, Jaime A Teixeira; Winarto, Budi

    2016-01-01

    The protocorm-like body (PLB) is the de facto somatic embryo in orchids. Here we describe detailed protocols for two orchid genera (hybrid Cymbidium Twilight Moon 'Day Light' and Dendrobium 'Jayakarta', D. 'Gradita 31', and D. 'Zahra FR 62') for generating PLBs. These protocols will most likely have to be tweaked for different cultivars as the response of orchids in vitro tends to be dependent on genotype. In addition to primary somatic embryogenesis, secondary (or repetitive) somatic embryogenesis is also described for both genera. The use of thin cell layers as a sensitive tissue assay is outlined for hybrid Cymbidium while the protocol outlined is suitable for bioreactor culture of D. 'Zahra FR 62'.

  13. Specific Proteins in the Indirect Somatic Embryogenesis of Freesia Refracta

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Using the young inflorescence segments of Freesia refracta as explants, indirect somatic embryogenesis of somatic cells was induced in a N6 medium supplemented with some exogenous hormones. SDS-polyacrylamide gel electrophoresis(SDS-PAGE) was used for the analysis of soluble proteins produced during the somatic embryogenesis of this plant. There are six polypeptides, which might play some roles in the process of somatic embryo development. Three polypeptides(45, 53 and 55 kD) were detected in the stages of embryogenic callus, globular embryoid, and embryoid with coleoptiles, except the embryoid with leaf. One polypeptide(83 kD) was specific for the stages of embryoid with coleoptiles and embryoid with leaf. One polypeptide(37 kD) was detected in the first two stages, namely, embryogenic callus and globular embryoid. One polypeptide(35 kD) was regularly synthesized in each stage, from embryogenic callus to embryoid with leaf.

  14. Somatic embryogenesis in suspension cultures of Gossypium klotzschianum anderss.

    Science.gov (United States)

    Price, H J; Smith, R H

    1979-01-01

    Somatic embryoids differentiated in suspension cultures of G. klotzschianum after 3-4 weeks of culture in a liquid medium containing glutamine (optimally, 10-15 mM). Embryogenesis occurred after a preculture of callus on a medium containing 10 mg/l of the cytokinin, 2iP. The embryoids had meristematic regions, a well formed epidermis, and formed roots and vestigial leaves. Asparagine was much less effective than glutamine in promoting embryoid differentiation. The presence of 2,4-D in the medium resulted in increased vigor of the suspension cultures and subsequently in the formation of many embryoids, but does not seem to be necessary for somatic embryogenesis in cotton.

  15. Alternative oxidase involvement in Daucus carota somatic embryogenesis.

    Science.gov (United States)

    Frederico, António Miguel; Campos, Maria Doroteia; Cardoso, Hélia Guerra; Imani, Jafargholi; Arnholdt-Schmitt, Birgit

    2009-12-01

    Plant alternative oxidase (AOX) is a mitochondrial inner membrane enzyme involved in alternative respiration. The critical importance of the enzyme during acclimation upon stress of plant cells is not fully understood and is still an issue of intensive research and discussion. Recently, a role of AOX was suggested for the ability of plant cells to change easily its fate upon stress. In order to get new insights about AOX involvement in cell reprogramming, quantitative real-time polymerase chain reaction (PCR) and inhibitor studies were performed during cell redifferentiation and developmental stages of Daucus carota L. somatic embryogenesis. Transcript level analysis shows that D. carota AOX genes (DcAOX1a and DcAOX2a) are differentially expressed during somatic embryogenesis. DcAOX1a shows lower expression levels, being mainly down-regulated, whereas DcAOX2a presented a large up-regulation during initiation of the realization phase of somatic embryogenesis. However, when globular embryos start to develop, both genes are down-regulated, being this state transient for DcAOX2a. In addition, parallel studies were performed using salicylhydroxamic acid (SHAM) in order to inhibit AOX activity during the realization phase of somatic embryogenesis. Embryogenic cells growing in the presence of the inhibitor were unable to develop embryogenic structures and its growth rate was diminished. This effect was reversible and concentration dependent. The results obtained contribute to the hypothesis that AOX activity supports metabolic reorganization as an essential part of cell reprogramming and, thus, enables restructuring and de novo cell differentiation.

  16. Asymmetric zygote division: A mystery starting point of embryogenesis.

    Science.gov (United States)

    Zhao, Jing; Sun, Meng-Xiang

    2016-10-02

    In angiosperm, asymmetric zygote division is critical for embryogenesis. The molecular mechanism underlying this process has gained a great attention recently. Some players involve in the control of both accurate position and correct orientation of zygote division plane have been found, which provide useful clues for the extensive investigations. It is getting clear that both internal and external factors are involved in this complex regulatory mechanism and the asymmetric zygote division seems with great impact in cell fate determination and embryo pattern formation.

  17. Ammonium-related metabolic changes affect somatic embryogenesis in pumpkin (Cucurbita pepo L.).

    Science.gov (United States)

    Mihaljević, Snježana; Radić, Sandra; Bauer, Nataša; Garić, Rade; Mihaljević, Branka; Horvat, Gordana; Leljak-Levanić, Dunja; Jelaska, Sibila

    2011-11-01

    Somatic embryogenesis in pumpkin can be induced on auxin-containing medium and also on hormone-free medium containing 1mM ammonium (NH(4)(+)) as the sole source of nitrogen. Growth of NH(4)(+)-induced embryogenic tissue was slow and caused considerable acidification of the culture medium. Small spherical cells with dense cytoplasma formed proembryogenic cell clusters that could not develop into late stage embryos. Buffering of NH(4)(+) medium with 25mM 2-(N-morpholino)-ethane-sulfonic acid enhanced tissue proliferation, but no further differentiation was observed. Later stage embryos developed only after re-supply of nitrogen in form of nitrate or l-glutamine. Effects of nitrogen status and pH of culture media on ammonium assimilation were analyzed by following the activity of glutamine synthetase (GS) in relation to phenylalanine ammonia-lyase (PAL). Increased activity of GS and PAL in NH(4)(+) induced tissue coincided with significantly higher activity of stress-related enzymes superoxide dismutase (SOD) and soluble peroxidase (POD), indicating oxidative stress response of embryogenic tissue to NH(4)(+) as the sole source of nitrogen. In addition, considerable increase was observed in callose accumulation and esterase activity, the early markers of somatic embryogenesis. Activity of stress-related enzymes decreased after the re-supply of nitrate (20mM) or Gln (10mM) in combination with NH(4)(+) (1mM), which subsequently triggered globular embryo development. Together, these results suggest that stress responses, as affected by nitrogen supply, contribute to the regulation of embryogenic competence in pumpkin.

  18. A new approach to direct somatic embryogenesis in Medicago.

    Science.gov (United States)

    Denchev, P; Velcheva, M; Atanassov, A

    1991-09-01

    A highly efficient system for direct somatic embryogenesis is described. Leaf sections originating from young trifoliate leaves of Medicago falcata line 47/1-5 and Medicago sativa line No2/9R, directly produced embryos after cultivation in liquid B5IV induction medium. In comparison with indirect somatic embryogenesis the system omits the callus stage and thus allows shortening of the process of somatic embryogenesis in alfalfa by 35-40 days. It permits the avoidance of secondary changes occurring during the process of dedifferentiation. A modified B5/3H medium containing Polyethylene Glycol 6000 promoted embryo development from globular up to torpedo stage. It was clearly shown that 2.5% Polyethylene Glycol stimulated this process for both H. falcata 47/1-5 and M. sativa No 2/9R. Maturation of torpedo stage embryos was carried out on solidified or liquid abscisic acidcontaining medium. A 30μM abscisic acid concentration was optimal in allowing one embryo to yield one plant. Somatic embryo conversion to plants and plant regeneration was performed on Murashige and Skoog medium. Regenerated plants showed a normal morphology.

  19. [Embryogenesis of microspore derived multicells in Capsicum annuum L].

    Science.gov (United States)

    Liu, Fan; Zhao, Hong; Chen, Bin; Zhang, Yue Yun

    2007-12-01

    Microspores and derived multicells were isolated and cultured in modified liquid CP medium after a 15d's preculture of anthers on solidified medium. Thirty days later in suspension culture, at 28 degrees C dark condition embryoids with different developmental stages were formed. Up to 22 embryoids could be formed from the cell suspension of 12 anthers, and about 23% of the embryoids were at the cotyledonary stage. Fluorescence and light microscope observations revealed that these embryoids derived from microspores. After several symmetrical division of the nuclei of uninucleated microspores, multi-nuclei cells or multi-cells were formed, and developed further into embryoids. There were white hairs on the surface of pepper embryoids, and some embryoids showed low vigor while others showed normal by TTC staining. Plants could be formed from torpedo and cotyledonary stage embryoids on solidified medium. Embryoids could be induced by 7 degrees C, 32 degrees C or 35 degrees C stress treatment on anthers, Higher embryogenesis frequencies were got at 7 degrees C and 35 degrees C condition in anther culture while 35 degrees C and 32 degrees C treatment showed a higher embryogenesis in isolated multicell culture. The reason of this result was discussed. There were obvious differences in embryogenesis frequency among different genotypes and different temperature stress conditions. Flow cytometric analysis revealed that there were haploidy, doubled haploidy and haploid-diploid chimera in the regenerated plants.

  20. Lodgepole pine: the first evidence of seed-based somatic embryogenesis and the expression of embryogenesis marker genes in shoot bud cultures of adult trees.

    Science.gov (United States)

    Park, So-Young; Klimaszewska, Krystyna; Park, Ji-Young; Mansfield, Shawn D

    2010-11-01

    Of the various alternatives for cloning elite conifers, somatic embryogenesis (SE) appears to be the best option. In recent years, significant areas of lodgepole pine (Pinus contorta) forest have been devastated by the mountain pine beetle (MPB) in Western Canada. In an attempt to establish an SE propagation system for MPB-resistant lodgepole pine, several families displaying varying levels of resistance were selected for experimentation involving shoot bud and immature seed explants. In bud cultures, eight embryogenic lines were induced from 2 of 15 genotypes following various treatments. Genotype had an important influence on embryogenic culture initiation, and this effect was consistent over time. These lines were identified by microscopic observation and genetic markers. Despite the abundance of early somatic embryos, the cultures have yet to develop into mature embryos. In contrast, immature zygotic embryos (ZEs) cultured from megagametophytes initiated SE at an early dominance stage via nodule-type callus in 1 of 10 genotypes. As part of the study, putative embryogenesis-specific genes, WOX2 (WUSCHELL homeobox 2) and HAP3A, were analyzed in cultures of both shoot bud explants and ZEs. On the basis of these analyses, we postulate that PcHAP3A was expressed mainly in callus and may be involved in cell division, whereas WOX2 was expressed mainly in embryonal mass (EM)-like tissues. The findings from this study, based on molecular assessment, suggest that the cell lines derived from bud cultures were truly EM. Moreover, these experimental observations suggest that PcWOX2 could be used as an early genetic marker to discriminate embryogenic cultures from callus.

  1. SOMATIC EMBRYOGENESIS AND MORPHOANATOMY OF Ocotea porosa SOMATIC EMBRYOS

    Directory of Open Access Journals (Sweden)

    Luciana Luiza Pelegrini

    2013-01-01

    Full Text Available Ocotea porosa seeds have strong tegument dormancy, recalcitrant behavior, low and irregular germination and that makes its natural propagation difficult. The aim of this study was to establish a protocol of regeneration of Ocotea porosa from somatic embryogenesis. Immature embryonic axes were inoculated on WPM culture medium supplemented with 2.4-D (200 μM combined or not with hydrolyzed casein or glutamine (0.5 or 1 g l-1, during 90 days. The repetitive embryogenesis was induced on medium with 2.4-D (22.62 μM combined with 2-iP (2.46 μM followed by transfer to culture medium with hydrolyzed casein or glutamine (1 g l-1 during 90 days. The maturation of somatic embryos was tested in culture medium containing NAA (0.5 μM and 2-iP (5; 10 and 20 μM. The highest percentage of somatic embryos induction (8.3% was observed in WPM culture medium containing 200 μM 2.4-D and 1 g L-1 hydrolyzed casein and the development of somatic embryos occurred indirectly. Repetitive somatic embryogenesis was promoted in WPM medium containing hydrolyzed casein or glutamine. However, the culture medium containing hydrolyzed casein promoted the maintenance of embryogenic capacity for more than two years. During the maturity phase, there was a low progression of globular embryos to cordiform and torpedo stages. The different ontogenetic stages of somatic embryos of Ocotea porosa were characterized by histological studies.

  2. SOMATIC EMBRYOGENESIS AND MORPHOANATOMY OF Ocotea porosa SOMATIC EMBRYOS

    Directory of Open Access Journals (Sweden)

    Luciana Luiza Pelegrini

    2013-12-01

    Full Text Available http://dx.doi.org/10.5902/1980509812343Ocotea porosa seeds have strong tegument dormancy, recalcitrant behavior, low and irregular germinationand that makes its natural propagation difficult. The aim of this study was to establish a protocol ofregeneration of Ocotea porosa from somatic embryogenesis. Immature embryonic axes were inoculatedon WPM culture medium supplemented with 2.4-D (200 μM combined or not with hydrolyzed casein orglutamine (0.5 or 1 g l-1, during 90 days. The repetitive embryogenesis was induced on medium with 2.4-D(22.62 μM combined with 2-iP (2.46 μM followed by transfer to culture medium with hydrolyzed caseinor glutamine (1 g l-1 during 90 days. The maturation of somatic embryos was tested in culture mediumcontaining NAA (0.5 μM and 2-iP (5; 10 and 20 μM. The highest percentage of somatic embryos induction(8.3% was observed in WPM culture medium containing 200 μM 2.4-D and 1 g L-1 hydrolyzed casein andthe development of somatic embryos occurred indirectly. Repetitive somatic embryogenesis was promotedin WPM medium containing hydrolyzed casein or glutamine. However, the culture medium containinghydrolyzed casein promoted the maintenance of embryogenic capacity for more than two years. Duringthe maturity phase, there was a low progression of globular embryos to cordiform and torpedo stages.The different ontogenetic stages of somatic embryos of Ocotea porosa were characterized by histologicalstudies.

  3. In vivo imaging of Nematostella vectensis embryogenesis and late development using fluorescent probes

    NARCIS (Netherlands)

    DuBuc, T.Q.; Dattoli, A.A.; Babonis, L.S.; Salinas-Saavedra, M.; Röttinger, E.; Martindale, M.Q.; Postma, M.

    2014-01-01

    Background: Cnidarians are the closest living relatives to bilaterians and have been instrumental to studying the evolution of bilaterian properties. The cnidarian model, Nematostella vectensis, is a unique system in which embryology and regeneration are both studied, making it an ideal candidate to

  4. Lipid Rafts: Keys to Sperm Maturation, Fertilization, and Early Embryogenesis

    Directory of Open Access Journals (Sweden)

    Natsuko Kawano

    2011-01-01

    Full Text Available Cell membranes are composed of many different lipids and protein receptors, which are important for regulating intracellular functions and cell signaling. To orchestrate these activities, the cell membrane is compartmentalized into microdomains that are stably or transiently formed. These compartments are called “lipid rafts”. In gamete cells that lack gene transcription, distribution of lipids and proteins on these lipid rafts is focused during changes in their structure and functions such as starting flagella movement and membrane fusion. In this paper, we describe the role of lipid rafts in gamete maturation, fertilization, and early embryogenesis.

  5. Pine embryogenesis: many licences to kill for a new life.

    Science.gov (United States)

    Vuosku, Jaana; Sutela, Suvi; Tillman-Sutela, Eila; Kauppi, Anneli; Jokela, Anne; Sarjala, Tytti; Häggman, Hely

    2009-10-01

    In plants, programmed cell death (PCD) is an important mechanism that controls normal growth and development as well as many defence responses. At present, research on PCD in different plant species is actively carried out due to the possibilities offered by modern methods in molecular biology and the increasing amount of genome data. The pine seed provides a favourable model for PCD because it represents an interesting inheritance of seed tissues as well as an anatomically well-described embryogenesis during which several tissues die via morphologically different PCD processes.

  6. Plant regeneration of Sapindus trifoliatus L. (soapnut) through somatic embryogenesis.

    Science.gov (United States)

    Desai, H V; Bhatt, P N; Mehta, A R

    1986-06-01

    Somatic embryogenesis and subsequent formation of plantlets was obtained from callus cultures derived from leaves of mature (over 60years old) Soapnut (Sapindus trifoliatus L.) tree. Callus was induced from leaf explants and grown on Murashige and Skoog's medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) and kinetin. Reduction of 2,4-D concentration during subsequent subcultures resulted in formation of embryoids. These embryoids developed further when transferred to a medium containing benzylaminopurine and kinetin and then to a hormone-free medium. Unless 5-methyl tryptophan was added and the level of sucrose raised, the embryoids began to recallus and failed to form plantlets.

  7. Efficient somatic embryogenesis and molecular marker based analysis as effective tools for conservation of red-listed plant Commiphora wightii

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    ASHOK KUMAR PARMAR

    2014-08-01

    Full Text Available A refined and high efficiency protocol for in vitro regeneration of Commiphora wightii, a red-listed medicinal plant of medicinal importance, has been developed through optimized somatic embryogenesis pathway. Cultures from immature fruits were induced and proliferated on B5 medium supplemented with 2.26 µM 2,4-D. Embryogenic calli were obtained and then maintained for extended periods by alternately subculturing on modified MS medium supplemented with 1.11 µM BAP, 0.57 µM IBA and with 0.5% activated charcoal or without PGR every 3-4 weeks. Cyclic embryogenesis was obtained. Late torpedo and early cotyledonary stages somatic embryos were regularly harvested from PGR-free modified MS medium. It was found that percent moisture available in culture containers play a critical role in maturation and subsequent germination of somatic embryos of C. wighti. Maximum germination of more than 80% was achieved through media recycling. Somatic embryo derived plants (emblings were acclimatized. After 5 months, acclimatized plants were out-planted in experimental field. These morphologically normal plants have been surviving for over 3 years. Molecular polymorphism was clearly evident when these plants were tested using RAPD primers, making the plants suitable for use in its species restoration program.

  8. SWATH-MS data of Drosophila melanogaster proteome dynamics during embryogenesis.

    Science.gov (United States)

    Fabre, Bertrand; Korona, Dagmara; Nightingale, Daniel J H; Russell, Steven; Lilley, Kathryn S

    2016-12-01

    Embryogenesis is one of the most important processes in the life of an animal. During this dynamic process, progressive cell division and cellular differentiation are accompanied by significant changes in protein expression at the level of the proteome. However, very few studies to date have described the dynamics of the proteome during the early development of an embryo in any organism. In this dataset, we monitor changes in protein expression across a timecourse of more than 20 h of Drosophila melanogaster embryonic development. Mass-spectrometry data were produced using a SWATH acquisition mode on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and more than 1950 proteins were quantified at each embryonic timepoint. The files presented here are a permanent digital map and can be reanalysed to test against new hypotheses. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD0031078.

  9. SNP linkage analysis and whole exome sequencing identify a novel POU4F3 mutation in autosomal dominant late-onset nonsyndromic hearing loss (DFNA15.

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    Hee-Jin Kim

    Full Text Available Autosomal dominant non-syndromic hearing loss (AD-NSHL is one of the most common genetic diseases in human and is well-known for the considerable genetic heterogeneity. In this study, we utilized whole exome sequencing (WES and linkage analysis for direct genetic diagnosis in AD-NSHL. The Korean family had typical AD-NSHL running over 6 generations. Linkage analysis was performed by using genome-wide single nucleotide polymorphism (SNP chip and pinpointed a genomic region on 5q31 with a significant linkage signal. Sequential filtering of variants obtained from WES, application of the linkage region, bioinformatic analyses, and Sanger sequencing validation identified a novel missense mutation Arg326Lys (c.977G>A in the POU homeodomain of the POU4F3 gene as the candidate disease-causing mutation in the family. POU4F3 is a known disease gene causing AD-HSLH (DFNA15 described in 5 unrelated families until now each with a unique mutation. Arg326Lys was the first missense mutation affecting the 3(rd alpha helix of the POU homeodomain harboring a bipartite nuclear localization signal sequence. The phenotype findings in our family further supported previously noted intrafamilial and interfamilial variability of DFNA15. This study demonstrated that WES in combination with linkage analysis utilizing bi-allelic SNP markers successfully identified the disease locus and causative mutation in AD-NSHL.

  10. Effect of Salicylic Acid on Somatic Embryogenesis and Plant Regeneration in Hedychium bousigonianum

    Science.gov (United States)

    The objective of this study was to induce somatic embryogenesis in Hedychium bousigonianum Pierre ex Gagnepain and assess the influence of salicylic acid (S) on somatic embryogenesis. Somatic embryos and subsequently regenerated plants were successfully obtained 30 days after transfer of embryogenic...

  11. Characterization of the Arabidopsis thaliana somatic embryogenesis receptor-like kinase 1 protein

    NARCIS (Netherlands)

    Shah, K.

    2001-01-01

    Transmembrane receptors are prime components of cellular signalling pathways and thus help determine cell fate, growth, differentiation, migration and death. Somatic embryogenesis is the process where by somatic cells develop into plants via the same morphological stages. The Somatic Embryogenesis R

  12. DNA polymerase delta is required for early mammalian embryogenesis.

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    Arikuni Uchimura

    Full Text Available BACKGROUND: In eukaryotic cells, DNA polymerase delta (Poldelta, whose catalytic subunit p125 is encoded in the Pold1 gene, plays a central role in chromosomal DNA replication, repair, and recombination. However, the physiological role of the Poldelta in mammalian development has not been thoroughly investigated. METHODOLOGY/PRINCIPAL FINDINGS: To examine this role, we used a gene targeting strategy to generate two kinds of Pold1 mutant mice: Poldelta-null (Pold1(-/- mice and D400A exchanged Poldelta (Pold1(exo/exo mice. The D400A exchange caused deficient 3'-5' exonuclease activity in the Poldelta protein. In Poldelta-null mice, heterozygous mice developed normally despite a reduction in Pold1 protein quantity. In contrast, homozygous Pold1(-/- mice suffered from peri-implantation lethality. Although Pold1(-/- blastocysts appeared normal, their in vitro culture showed defects in outgrowth proliferation and DNA synthesis and frequent spontaneous apoptosis, indicating Poldelta participates in DNA replication during mouse embryogenesis. In Pold1(exo/exo mice, although heterozygous Pold1(exo/+ mice were normal and healthy, Pold1(exo/exo and Pold1(exo/- mice suffered from tumorigenesis. CONCLUSIONS: These results clearly demonstrate that DNA polymerase delta is essential for mammalian early embryogenesis and that the 3'-5' exonuclease activity of DNA polymerase delta is dispensable for normal development but necessary to suppress tumorigenesis.

  13. The role of chromatin modifications in somatic embryogenesis in plants

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    Clelia eDe-la-Peña

    2015-08-01

    Full Text Available Somatic embryogenesis (SE is a powerful tool for plant genetic improvement, when used in combination with agricultural traditional techniques, and it is being used to understand the different processes that occur during the development of plant embryogenesis. SE onset depends on a complex network of interactions among plant growth regulators, mainly auxins and cytokinins, during the proembryogenic early stages, and ethylene, gibberellic and abscisic acids later in the development of the somatic embryos. These growth regulators control spatial and temporal regulation of multiple genes in order to initiate the change in the genetic program of the somatic cells, as well as the transition among embryo developmental stages. In recent years, epigenetic mechanisms have emerged as critical factors during SE. Some early reports indicate that auxins modify the levels of DNA methylation in embryogenic cells. The changes in DNA methylation patterns are associated with the regulation of several genes involved in SE, such as WUS, BBM1, LEC, and several others. In this review, we highlight the more recent discoveries in the role of epigenetic regulation of SE. In addition, we include a survey of novel approaches to the study of SE, and new opportunities to focus SE studies.

  14. Reproduction of the Medicinal Plant Pelargonium sidoides via Somatic Embryogenesis.

    Science.gov (United States)

    Duchow, Stefanie; Blaschek, Wolfgang; Classen, Birgit

    2015-08-01

    The medicinal plant Pelargonium sidoides DC. (Geraniaceae) was traditionally used for the treatment of the common cold and cough in South Africa. Today an aequous-ethanolic root extract from this plant is approved for the treatment of acute bronchitis and is globally marketed also as an immunostimulant. The increasing demand of the plant material for the industrial production indicates the need of new effective methods for the propagation of P. sidoides. Here we report somatic embryogenesis and in vitro plantlet regeneration from somatic cells of inflorescence shoots and petioles of P. sidoides. A one-week cultivation of explants in media containing different concentrations of thidiazuron (1, 2.2, 3, and 4 mg/L) followed by a cultivation period without phytohormones resulted in the induction of somatic embryos within 2-4 weeks. After 2-4 months, the embryos generated roots and could be transferred into a greenhouse, where flower formation took place and the development of seeds occurred with high germination rates. The root umckalin concentration, determined by high-performance thin-layer chromatography, was comparable to that of seed-cultivated plants (100 ± 6 vs. 113 ± 10 µg umckalin/g dried roots). For the first time, direct somatic embryogenesis has been established as an appropriate cultivation method for P. sidoides plants used as raw material in the pharmaceutical industry. Moreover, genetically identical plants (chemical races) can be easily generated by this procedure.

  15. Stage-specific effects of teratogens on sea urchin embryogenesis.

    Science.gov (United States)

    Graillet, C; Pagano, G; Girard, J P

    1993-01-01

    The effect of direct (chlorambucil and allopurinol) and indirect (cyclophosphamide) teratogens on the fertilization and early development of sea urchin embryos has been investigated. Fertilization was affected by none of the drugs tested. Continuous exposure of embryos to chlorambucil (10(-6) to 3 x 10(-4) M) starting after fertilization delayed the first cleavage and hatching. Developmental defects in chlorambucil-treated embryos consisted mainly of blastula and gastrula-arrested embryos and in a limited number (25%) of plutei with malformed gut or skeleton. Post-hatching exposure to chlorambucil led to malformed plutei only. Early (pre-hatching) exposure to allopurinol (10(-6) to 10(-3) M) did not affect cleavage but induced developmental defects in a ratio comparable to chlorambucil. Post-hatching exposure to allopurinol failed to affect the embryogenesis. The indirect teratogen cyclophosphamide (10(-6) to 3 x 10(-5) M) had no effect on the early embryogenesis. Results were discussed in view of using sea urchin embryos to detect and analyze the early mechanisms of teratogenic action.

  16. The mechanisms of primordial germ cell determination during embryogenesis in molluscan species

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    M Obata

    2012-12-01

    Full Text Available Primordial germ cells (PGCs are the first germ cells distinguishable from surrounding somatic cells during embryogenesis. In many animal species PGC specification is generally classified into two modes: preformation, in which PGCs are determined by maternally inherited components in early development, and epigenesis, in which PGCs arise from proximal somatic cells by inductive signal in late development. In this review we focused on the process of PGC formation in molluscan bivalves and gastropods and compared the PGC specification modes of these two classes. Several reports indicated that bivalves tend to adopt preformation, as maternally inherited germline-specific genes are transcribed in specific blastomeres differentiating into PGCs. In gastropods, maternal germline-specific genes are transcribed in mesodermal stem cells. PGCs seem to be epigenetically determined from mesodermal stem cells by inductive signals after the veliger larval stage, which indicates that PGC precursor cells not only generate germline tissues but also generate mesodermal somatic tissues. The common origin of germline and mesodermal somatic tissues is observed in the annelids Platyhelminthes and Cnidaria, and is considered to be an ancient mode of germ cell determination. We suggest that gastropods retain the ancient PGC specification mode, while bivalves switch their PGC specification mode to preformation.

  17. Characterization and expression analysis of somatic embryogenesis receptor-like kinase genes from Phalaenopsis.

    Science.gov (United States)

    Huang, Y W; Tsai, Y J; Chen, F C

    2014-12-18

    Somatic embryogenesis receptor-like kinase (SERK) genes have been found to be involved in the somatic embryogenesis of several plant species. We identified and characterized 5 PhSERK genes in the Phalaenopsis orchid. The amino acid sequences of PhSERKs and other SERK proteins are highly conserved, with the highest homology observed in the leucine-rich repeat-receptor-like kinase domain. All 5 PhSERKs were expressed in all Phalaenopsis organs examined (root, leaf, shoot apical meristem, and flower), with the strongest expression, particularly for PhSERK1 and 3, in the shoot apical meristem of mature plants. Expression of all PhSERKs was downregulated during early floral bud development and was upregulated gradually until the semi-open flower stage was reached. All 5 PhSERKs were expressed during both seed germination and protocorm-like-body (PLB) development. In germinated seeds, quantitative real-time PCR revealed upregulation of all PhSERKs except PhSERK4 at 1 week and downregulation after 4 weeks. The 5 PhSERKs were differentially expressed in the early stage of PLB development and maintained substantial levels during PLB formation, with PhSERK1 and 5 upregulated 1 week after culture and PhSERK2, 3, and 4 downregulated over this period. Because physical wounding of PLB stimulates secondary PLB formation, the PhSERK5 expression peak at week 3 coincided with visible and fully developed secondary PLBs. PhSERK5 may be important in PLB induction and subsequent development. Our PhSERK expression analysis revealed that these genes have a broad role during orchid plant development.

  18. Acidic Conditions During Open System Weathering on Late Noachian/Early Hesperian Mars? Newly Identified Outcrops of Alunite and Jarosite from Orbital CRISM Data

    Science.gov (United States)

    Ehlmann, Bethany; Dundar, Murat

    2016-10-01

    Sequences of Al-phyllosilicates atop Fe,Mg-phylloslicates occur in multiple regions of Mars, including Mawrth Vallis/northern Arabia Terra, Nili Fossae/Northeast Syrtis Major, Terra Sirenum/Eridania basin, northern Hellas, and portions of Valles Marineris. The sequences are exposed beneath unaltered capping materials with Early Hesperian surface ages, thus implying phyllosilicate formation occurred earlier. Because of the presence of clay minerals, the sequences are certainly a product of water interactions with rocks and sediments, but key questions remain about the environmental conditions implied. Are Al-phyllosilicates simply a result of alteration of a silicic precursor? Or do they represent the end product of substantial open system leaching of a basaltic protolith? Was open system leaching substantial because of high water throughput, long cumulative duration, acidity, or some combination? Each scenario leads to Al-phyllosilicate formation but with different accompanying mineral phases in response to pH, Eh, and chemical species concentrations in the fluids. Key to further progress in constraining the environmental conditions of alteration is more sophisticated spectral analyses to identify intermixed phases and isolate rare spectral classes within the Al phyllosilicate units.Here, we employ a newly developed, non-parametric Bayesian algorithm [1] for semi-automatic identification of rare spectral classes. We employ this algorithm on 139 CRISM images in areas with reported regional-scale occurrences of Al-phyllosilicates that were compiled from the literature [e.g. 2, 3]. Dozens of detections of the minerals alunite and jarosite were made with the algorithm and then verified by manual analysis. These sulfate hydroxides form only at low pHs, and thus their presence tightly constrains water chemistry. Crucial for understanding whether the alunite and jarosite deposits are contemporaneous with the Al phyllosilicates or later overprinting deposits is study of

  19. Developmental pathway of somatic embryogenesis in Picea abies as revealed by time-lapse tracking.

    Science.gov (United States)

    Filonova, L H; Bozhkov, P V; von Arnold, S

    2000-02-01

    common histodifferentiation pattern with zygotic embryos. Although the earliest stages of somatic embryo development comparable to proembryogeny could not be characterized, the subsequent developmental processes correspond closely to what occurs in the course of early and late zygotic embryogeny. A model for somatic embryogenesis pathways in Picea abies is presented.

  20. Identification of QTLs associated with callogenesis and embryogenesis in oil palm using genetic linkage maps improved with SSR markers.

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    Ngoot-Chin Ting

    Full Text Available Clonal reproduction of oil palm by means of tissue culture is a very inefficient process. Tissue culturability is known to be genotype dependent with some genotypes being more amenable to tissue culture than others. In this study, genetic linkage maps enriched with simple sequence repeat (SSR markers were developed for dura (ENL48 and pisifera (ML161, the two fruit forms of oil palm, Elaeis guineensis. The SSR markers were mapped onto earlier reported parental maps based on amplified fragment length polymorphism (AFLP and restriction fragment length polymorphism (RFLP markers. The new linkage map of ENL48 contains 148 markers (33 AFLPs, 38 RFLPs and 77 SSRs in 23 linkage groups (LGs, covering a total map length of 798.0 cM. The ML161 map contains 240 markers (50 AFLPs, 71 RFLPs and 119 SSRs in 24 LGs covering a total of 1,328.1 cM. Using the improved maps, two quantitative trait loci (QTLs associated with tissue culturability were identified each for callusing rate and embryogenesis rate. A QTL for callogenesis was identified in LGD4b of ENL48 and explained 17.5% of the phenotypic variation. For embryogenesis rate, a QTL was detected on LGP16b in ML161 and explained 20.1% of the variation. This study is the first attempt to identify QTL associated with tissue culture amenity in oil palm which is an important step towards understanding the molecular processes underlying clonal regeneration of oil palm.

  1. Somatic embryogenesis and plant regeneration of Capsicum baccatum L.

    Directory of Open Access Journals (Sweden)

    Peddaboina Venkataiah

    2016-06-01

    Full Text Available A plant regeneration protocol via somatic embryogenesis was achieved in cotyledon and leaf explants of Capsicum baccatum, when cultured on MS medium supplemented with various concentrations of 2,4-dichlorophenoxy acetic acid (2,4-D, 0.5–5.0 mg l−1 in combination with Kinetin (Kn, 0.5 mg l−1 and 3% sucrose. Various stages were observed during the development of somatic embryos, including globular, heart, and torpedo-stages. Torpedo stage embryos were separated from the explants and subcultured on medium supplemented with various concentrations of different plant growth regulators for maturation. Maximum percentage (55% of somatic embryo germination and plantlet formation was found at 1.0 mg l−1 BA. Finally, about 68% of plantlets were successfully established under field conditions. The regenerated plants were morphologically normal, fertile and able to set viable seeds.

  2. Aquinas's account of human embryogenesis and recent interpretations.

    Science.gov (United States)

    Eberl, Jason T

    2005-08-01

    In addressing bioethical issues at the beginning of human life, such as abortion, in vitro fertilization, and embryonic stem cell research, one primary concern regards establishing when a developing human embryo or fetus can be considered a person. Thomas Aquinas argues that an embryo or fetus is not a human person until its body is informed by a rational soul. Aquinas's explicit account of human embryogenesis has been generally rejected by contemporary scholars due to its dependence upon medieval biological data, which has been far surpassed by current scientific research. A number of scholars, however, have attempted to combine Aquinas's basic metaphysical account of human nature with current embryological data to develop a contemporary Thomistic account of a human person's beginning. In this article, I discuss two recent interpretations in which it is argued that a human person does not begin to exist until a fetus has developed a functioning cerebral cortex.

  3. Micropropagation of Citrus spp. by organogenesis and somatic embryogenesis.

    Science.gov (United States)

    Chiancone, Benedetta; Germanà, Maria Antonietta

    2013-01-01

    Citrus spp., the largest fruit crops produced worldwide, are usually asexually propagated by cuttings or grafting onto seedling rootstocks. Most of Citrus genotypes are characterized by polyembryony due to the occurrence of adventive nucellar embryos, which lead to the production of true-to-type plants by seed germination. Tissue culture and micropropagation, in particular, are valuable alternatives to traditional propagation to obtain a high number of uniform and healthy plants in a short time and in a small space. Moreover, in vitro propagation provides a rapid system to multiply the progeny obtained by breeding programs, allows the use of monoembryonic and seedless genotypes as rootstocks, and it is very useful also for breeding and germplasm preservation.In this chapter, two protocols regarding organogenesis of a rootstock and somatic embryogenesis of a cultivar have been described.

  4. Embryogenesis of esophageal atresia: Is localized vascular accident a factor?

    Directory of Open Access Journals (Sweden)

    Dutta Hemonta

    2009-01-01

    Full Text Available Several theories on embryogenesis of esophageal atresia have been proposed, none could explain the whole spectrum of this anomaly. We report a new variant of esophageal atresia in which the two blind pouches were joined by an atretic band. Histology of the atretic part showed groups of striated muscle arranged haphazardly without any lumen. The existing theories on etiology of esophageal atresia cannot explain this variant. However, localized vascular accident during intrauterine life resulting in disturbances in regional microcirculation could be a possible factor as demonstrated by Louw and Barnard in relation to jejunoileal atresia. This is contrary to the current understanding that disproportionate growth of the horizontal esophageal folds results in esophageal atresia.

  5. [Direct and indirect somatic embryogenesis in Freesia refracta].

    Science.gov (United States)

    Wang, L; Duan, X G; Hao, S

    1999-06-01

    Somatic embryogenesis can be induced in tissue cultures of Freesia refracta either directly from the epidermal cells of explant, or indirectly via intervening callus. In direct pathway, somatic embryos were in contact with maternal tissue in a suspensor-like structure. In indirect pathway, the explants first proliferacted to give rise to calluses before embryoids were induced. The two sorts of calluses were defined to embryogenic callus and non-embryogenic callus according to producing of somatic embryos. An indirect somatic embryo is developed from a pre-embryogenically determined cell. This kind of somatic embryo has no suspensor structure instead of a complex with maternal tissue. Somatic embryos have their own vascular tissues, and can develop new plantlets independently.

  6. Transcriptional identification and characterization of differentially expressed genes associated with embryogenesis in radish (Raphanus sativus L.).

    Science.gov (United States)

    Zhai, Lulu; Xu, Liang; Wang, Yan; Zhu, Xianwen; Feng, Haiyang; Li, Chao; Luo, Xiaobo; Everlyne, Muleke M; Liu, Liwang

    2016-02-23

    Embryogenesis is an important component in the life cycle of most plant species. Due to the difficulty in embryo isolation, the global gene expression involved in plant embryogenesis, especially the early events following fertilization are largely unknown in radish. In this study, three cDNA libraries from ovules of radish before and after fertilization were sequenced using the Digital Gene Expression (DGE) tag profiling strategy. A total of 5,777 differentially expressed transcripts were detected based on pairwise comparison in the three libraries (0_DAP, 7_DAP and 15_DAP). Results from Gene Ontology (GO) and pathway enrichment analysis revealed that these differentially expressed genes (DEGs) were implicated in numerous life processes including embryo development and phytohormones biosynthesis. Notably, some genes encoding auxin response factor (ARF ), Leafy cotyledon1 (LEC1) and somatic embryogenesis receptor-like kinase (SERK ) known to be involved in radish embryogenesis were differentially expressed. The expression patterns of 30 genes including LEC1-2, AGL9, LRR, PKL and ARF8-1 were validated by qRT-PCR. Furthermore, the cooperation between miRNA and mRNA may play a pivotal role in the radish embryogenesis process. This is the first report on identification of DEGs profiles related to radish embryogenesis and seed development. These results could facilitate further dissection of the molecular mechanisms underlying embryogenesis and seed development in radish.

  7. Analysis of chlorophyll fluorescence reveals stage specific patterns of chloroplast-containing cells during Arabidopsis embryogenesis.

    Science.gov (United States)

    Tejos, Ricardo I; Mercado, Ana V; Meisel, Lee A

    2010-01-01

    The basic body plan of a plant is established early in embryogenesis when cells differentiate, giving rise to the apical and basal regions of the embryo. Using chlorophyll fluorescence as a marker for chloroplasts, we have detected specific patterns of chloroplast-containing cells at specific stages of embryogenesis. Non-randomly distributed chloroplast-containing cells are seen as early as the globular stage of embryogenesis in Arabidopsis. In the heart stage of embryogenesis, chloroplast containing cells are detected in epidermal cells as well as a central region of the heart stage embryo, forming a triangular septum of chloroplast-containing cells that divides the embryo into three equal sectors. Torpedo stage embryos have chloroplast-containing epidermal cells and a central band of chloroplast-containing cells in the cortex layer, just below the shoot apical meristem. In the walking-stick stage of embryogenesis, chloroplasts are present in the epidermal, cortex and endodermal cells. The chloroplasts appear reduced or absent from the provascular and columella cells of walking-stick stage embryos. These results suggest that there is a tight regulation of plastid differentiation during embryogenesis that generates specific patterns of chloroplast-containing cells in specific cell layers at specific stages of embryogenesis.

  8. Dynamic nucleosome organization at hox promoters during zebrafish embryogenesis.

    Directory of Open Access Journals (Sweden)

    Steven E Weicksel

    Full Text Available Nucleosome organization at promoter regions plays an important role in regulating gene activity. Genome-wide studies in yeast, flies, worms, mammalian embryonic stem cells and transformed cell lines have found well-positioned nucleosomes flanking a nucleosome depleted region (NDR at transcription start sites. This nucleosome arrangement depends on DNA sequence (cis-elements as well as DNA binding factors and ATP-dependent chromatin modifiers (trans-factors. However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome must undergo a broad reprogramming event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development, we map nucleosome positions at the promoter region of 37 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a progressive process that takes place over several stages. At stages immediately after fertilization, nucleosomes appear to be largely disordered at hox promoter regions. At stages after activation of the embryonic genome, nucleosomes are detectable at hox promoters, with positions becoming more uniform and more highly occupied. Since the genomic sequence is invariant during embryogenesis, this progressive change in nucleosome arrangement suggests that trans-factors play an important role in organizing nucleosomes during embryogenesis. Separating hox genes into expressed and non-expressed groups shows that expressed promoters have better positioned and occupied nucleosomes, as well as distinct NDRs, than non-expressed promoters. Finally, by blocking the retinoic acid-signaling pathway, we disrupt early hox gene transcription, but observe no effect on nucleosome positions, suggesting that active hox transcription is not a driving force behind the arrangement of nucleosomes at the promoters of hox genes during early development.

  9. Effects of Ethephon, Ethylene, and 2,4-Dichlorophenoxyacetic Acid on Asexual Embryogenesis in Vitro12

    Science.gov (United States)

    Tisserat, Brent; Murashige, Toshio

    1977-01-01

    Asexual embryogenesis in Daucus carota L. `Queen Anne's Lace' callus was suppressed by Ethephon, ethylene, and 2,4-dichlorophenoxyacetic acid (2,4-D). The Ethephon effect could be attributed to volatile and nonvolatile substances. The volatile component was probably entirely ethylene. Ethylene was liberated in the cultures in direct proportion to Ethephon added to the medium. Autoclaving of Ethephon caused a substantial decrease of measurable ethylene. Continuous exposure of callus to 5 μl/l ethylene depressed somatic cell embryogenesis, but not markedly. Depression of embryogenesis by 2,4-D was unrelated to ethylene evolution. PMID:16660109

  10. Somatic Embryogenesis Induction and Plant Regeneration in Strawberry Tree (Arbutus unedo L.).

    Science.gov (United States)

    Martins, João F; Correia, Sandra I; Canhoto, Jorge M

    2016-01-01

    Somatic embryogenesis is a powerful tool both for cloning and studies of genetic transformation and embryo development. Most protocols for somatic embryogenesis induction start from zygotic embryos or embryonic-derived tissues which do not allow the propagation of elite trees. In the present study, a reliable protocol for somatic embryogenesis induction from adult trees of strawberry tree is described. Leaves from in vitro proliferating shoots were used to induce somatic embryo formation on a medium containing an auxin and a cytokinin. Somatic embryos germinated in a plant growth regulator-free medium.

  11. Cytohistological analysis of somatic embryogenesis in cucumber (Cucumis sativus L. II. Natural fluorescence and direct somatic embryogenesis from protoplasts

    Directory of Open Access Journals (Sweden)

    W. Burza

    2014-02-01

    Full Text Available The development of protoplast derived from somatic embryos and some of their characteristics were compared with embryos from suspension and in vivo in the same B line. Embryos formed in a protoplast culture differed from others that their younger stages contained vacuolated cells, and older ones had altered morphological and histological structure. Somatic embryogenesis is more regular from suspension then from protoplasts. No distinct differences were observed in the rate of embryo development in vivo and in vitro, and in vitro embryos show a larger variation in size at the same stage. Embryos in vitro with fluorescence are generally larger than zygotic ones at each stage. The use of fluorescence is suggested for the selection of heterokariocytes after protoplast fusion.

  12. Late Budgets

    DEFF Research Database (Denmark)

    Andersen, Asger Lau; Lassen, David Dreyer; Nielsen, Lasse Holbøll Westh

    The budget forms the legal basis of government spending. If a budget is not in place at the beginning of the fiscal year, planning as well as current spending are jeopardized and government shutdown may result. This paper develops a continuous-time war-of-attrition model of budgeting...... in a presidential style-democracy to explain the duration of budget negotiations. We build our model around budget baselines as reference points for loss averse negotiators. We derive three testable hypotheses: there are more late budgets, and they are more late, when fiscal circumstances change; when such changes...... are negative rather than positive; and when there is divided government. We test the hypotheses of the model using a unique data set of late budgets for US state governments, based on dates of budget approval collected from news reports and a survey of state budget o¢ cers for the period 1988...

  13. Late Budgets

    DEFF Research Database (Denmark)

    Andersen, Asger Lau; Lassen, David Dreyer; Nielsen, Lasse Holbøll Westh

    are negative rather than positive; and when there is divided government. We test the hypotheses of the model using a unique data set of late budgets for US state governments, based on dates of budget approval collected from news reports and a survey of state budget o¢ cers for the period 1988......The budget forms the legal basis of government spending. If a budget is not in place at the beginning of the fiscal year, planning as well as current spending are jeopardized and government shutdown may result. This paper develops a continuous-time war-of-attrition model of budgeting...... in a presidential style-democracy to explain the duration of budget negotiations. We build our model around budget baselines as reference points for loss averse negotiators. We derive three testable hypotheses: there are more late budgets, and they are more late, when fiscal circumstances change; when such changes...

  14. Ontogenic appearance of MHC class I (B-F) antigens during chicken embryogenesis

    DEFF Research Database (Denmark)

    Dunon, D; Salomonsen, J; Skjødt, K;

    1990-01-01

    Expression of chicken MHC class I (B-F) antigens during ontogeny was determined by binding of anticlass I antibody and appearance of B-F transcripts by Northern blotting in chicken organs during embryogenesis until 2 weeks after hatching. MHC class I transcripts first become detectable in day 6.......5 of embryogenesis. B-F cell-surface expression first becomes detectable in hemopoietic organs by day 10-12 of embryogenesis and somewhat later in nonhemopoietic organs. Flow cytometry analysis of hemopoietic cells throughout embryogenesis revealed B-Fhi and B-Flo cell populations. The percentage of B-F+ cells...... in spleen and bone marrow decreased around hatching, which could reflect either cell flows in these organs during this period or the sensitivity of hemopoietic cells to hatching stress. Udgivelsesdato: 1990-null...

  15. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis

    OpenAIRE

    Monteiro, Mariza; Appezzato-da-Glória, Beatriz; Valarini,Maria José; Oliveira, Carlos Alberto; Vieira, Maria Lucia Carneiro

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  16. Cell dedifferentiation, callus induction and somatic embryogenesis in Crataegus spp.

    Science.gov (United States)

    Taimori, N; Kahrizi, D; Abdossi, V; Papzan, A H

    2016-09-30

    The present study describes the effects of light conditions, different kinds and concentrations of auxins [Naphthylacetic acid (NAA) and dichlorophenoxyacetic acid (2,4-D)] with cytokinin (Kin) in MS medium on callus induction and embryogenesis in Crataegus pseudoheterophylla, C. aronia and C.meyeri. At first leave explants sections were cultured on different combinations of plant growth regulators in dark and light for callus initiation and light conditions to evaluation the percentage and duration of survival, callus diameter, callus fresh weight and dry. Results of effects of plant growth regulators and light conditions on callus initiation revealed that highest percentage of callus initiation leaves in treatment (0.5 mg/l 2.4-D+0.5 mg/l KIN) for species C.pseudoheterophylla in dark conditions (100%). Dark conditions (100%) were more effective on callogenesis than light conditions (Photoperiodicity of 16-h and at light intensity of 40 µmol m-2 s-1). The callus induction of in vitro (64-100%) leaves was better than the ex vitro ones (0-100%). The combination of 2,4-D and Kin of in vitro leaves callogenesis has been indicated faster (one weeks) than the other combinations. The results also showed that the highest percentage (100%) and survival duration (6 months) was found in species C. pseudoheterophylla and C. meyeri in 0.1 mg/l 2,4.D + 0.5 mg/l KIN and 0.5 mg/l 2,4.D + 0.5 mg/l Kin. The minimum survival (0%) was absorbed in species C. aronia in 1 mg/l NAA. Maximum callus (10.63 and 10.00 mm respectively) was shown in 0.1 mg/l 2,4.D + 0.5 mg/l Kin and 0.5 mg/l 2,4.D + 0.5 mg/l Kin and was not significant differences after five week among species. The results showed that the highest fresh (1081.49 mg) and dry weight (506.88 and 506.98 mg respectively) was absorbed in species C. pseudoheterophylla in 0.1 mg/l 2,4.D + 0.5 mg/l Kin and 0.5 mg/l 2,4.D + 0.5 mg/l Kin. The embryogenesis was not occurred in any plant growth regulator combinations and species. The

  17. Direct somatic embryogenesis and synthetic seed production from Paulownia elongata.

    Science.gov (United States)

    Ipekci, Z; Gozukirmizi, N

    2003-08-01

    We have developed a reproducible system for efficient direct somatic embryogenesis from leaf and internodal explants of Paulownia elongata. The somatic embryos obtained were subsequently encapsulated as single embryos to produce synthetic seeds. Several plant growth regulators [6-benzylaminopurine, indole-3-acetic acid, alpha-naphthaleneacetic acid, kinetin and thidiazuron (TDZ)] alone or in combination were tested for their capacity to induce somatic embryogenesis. The highest induction frequencies of somatic embryos were obtained on Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% Phytagel, 500 mg l(-1) casein hydrolysate and 10 mg l(-1) TDZ (medium MS10). Somatic embryos were induced from leaf (69.8%) and internode (58.5%) explants on MS10 medium after 7 days. Subsequent withdrawal of TDZ from the induction medium resulted in the maturation and growth of the embryos into plantlets on MS basal media. The maturation frequency of somatic embryos from leaf and internodal explants was 50.8% and 45.8%, respectively. Subculturing of mature embryos led to their germination on the same medium with a germination frequency of 50.1% and 29.8% from leaf and internode explants, respectively. Somatic embryos obtained directly on leaf explants were used for encapsulation in liquid MS medium containing different concentrations of sodium alginate with a 30-min exposure to 50 m M CaCl(2). A 3% sodium alginate concentration provided a uniform encapsulation of the embryos with survival and germination frequencies of 73.7% and 53.3%, respectively. Storage at 4 degrees C for 30 days or 60 days significantly reduced the survival and complete germination frequencies of both encapsulated and non-encapsulated embryos relative to those of non-stored somatic embryos. However, the survival and germination rates of encapsulated embryos increased following storage at 4 degrees C. After 30 days or 60 days of storage, the survival rates of encapsulated embryos were 67.8% and 53

  18. DIRECT AND INDIRECT SOMATIC EMBRYOGENESIS ON ARABICA COFFEE (Coffea arabica

    Directory of Open Access Journals (Sweden)

    Meynarti Sari Dewi Ibrahim

    2013-10-01

    Full Text Available Propagation of Coffea arabica L. through direct and indirect somatic embryogenesis technique is promising for producing large number of coffee seedlings. The objectives of the research were to evaluate methods for direct and indirect somatic embryo-genesis induction of C. arabica var. Kartika. The explants were the youngest fully expanded leaves of arabica coffee. The evalu-ated medium was modified Murashige and Skoog (MS medium supplemented with a combination of 2.26 µM 2,4-D + 4.54 or 9.08 µM thidiazuron; 4.52 µM 2,4-D + 4.54 or 9.08 µM thidiazuron; or 9.04 µM 2,4-D + 9.08 µM thidiazuron. Both calli (100 mg and pre-embryos developed from the edge of leaf explants were subcultured into regeneration medium (half strength MS with modified vitamin, supplemented with kinetine 9.30 µM and adenine sulfate 40 mg L-1. The results showed coffee leaf explant cultured on medium containing 2.26 µM 2,4-D + 4.54 or 9.08 µM thidiazuron to induce direct somatic embriogenesis from explant, while that of 4.52 or 9.04 µM 2,4-D + 9.08 µM thidiazuron to induced indirect somatic embrio-genesis. The medium for calli induction from coffee by explants was medium supplemented with 4.52 or 9.04 µM 2,4-D in combination with 9.08 µM thidiazuron. On the other hand, the best medium for activation of induction of somatic embryos was MS medium supplemented with 9.04 µM 2,4-D + 9.08 µM thidiazuron. Based on this results, the first step for developing micropropagation for coffee has been resolved. The subsequent studies will be directed to evaluate agronomic performance of the derived planting materials.

  19. Syntaxin, VAMP, and Rab3 are selectively expressed during sea urchin embryogenesis.

    Science.gov (United States)

    Conner, S D; Wessel, G M

    2001-01-01

    SNARE and rab protein family members were originally identified in terminally differentiated cell types. These proteins are phylogenetically conserved and while compelling evidence demonstrates their involvement in the secretory pathway, their exact function is debated. We recently identified SNARE protein family members in the sea urchin egg and provided evidence that rab3 functions in the exocytosis of cortical granules. Here we tested the hypothesis that these same proteins might also be present throughout embryogenesis to mediate membrane fusion events. We provide evidence that the sea urchin possesses a low complexity of gene family members of syntaxin, VAMP, and rab3 and that these proteins are not only present during development, but are enriched in regions of the embryo with active secretory roles. We found accumulation of each family member in the apical and basal aspects of cleaving blastomeres, indicative of bidirectional secretion into the extraembryonic environment and blastocoel. Elevated levels of syntaxin, VAMP, and rab3 were also found in the mesodermally derived pigment cells that invade and move within the ectoderm. These cells likely rely on SNARE and rab proteins to enable mobility by mediating the secretion of enzymes that break adhesion to neighboring cells and the extracellular matrix. In addition, these secretory proteins are enriched in the gut following gastrulation. Thus, we conclude that VAMP, syntaxin, and rab3 mediate a variety of secretory events that is important for development.

  20. Impaired imprinting and social behaviors in chicks exposed to mifepristone, a glucocorticoid receptor antagonist, during the final week of embryogenesis.

    Science.gov (United States)

    Nishigori, Hideo; Kagami, Keisuke; Nishigori, Hidekazu

    2014-03-15

    The effects of glucocorticoid receptor dysfunction during embryogenesis on the imprinting abilities and social behaviors of hatchlings were examined using "fertile hen's egg-embryo-chick" system. Of embryos treated with mifepristone (0.4μmol/egg) on day 14, over 75% hatched a day later than the controls (day 22) without external anomalies. The mifepristone-treated hatchlings were assayed for imprinting ability on post-hatching day 2 and for social behaviors on day 3. The findings were as follows: imprinting ability (expressed as preference score) was significantly lower in mifepristone-treated hatchlings than in controls (0.65±0.06 vs. 0.92±0.02, P<0.005). Aggregation tests to evaluate the speed (seconds) required for four chicks, individually isolated with cardboard dividers in a box, to form a group after removal of the barriers showed that aggregation was significantly slower in mifepristone-treated hatchlings than in controls (8.7±1.1 vs. 2.6±0.3, P<0.001). In belongingness tests to evaluate the speed (seconds) for a chick isolated at a corner to join a group of three chicks placed at the opposite corner, mifepristone-treated hatchlings took significantly longer than controls (4.5±0.4/40 cm vs. 2.4±0.08/40 cm, P<0.001). In vocalization tests, using a decibel meter to measure average decibel level/30s (chick vocalization), mifepristone-treated hatchlings had significantly weaker vocalizations than controls (14.2±1.9/30s vs. 26.4±1.3/30s P<0.001). In conclusion, glucocorticoid receptor dysfunction during the last week embryogenesis altered the programming of brain development, resulting in impaired behavioral activities in late life. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. OsMPK6 plays a critical role in cell differentiation during early embryogenesis in Oryza sativa.

    Science.gov (United States)

    Yi, Jakyung; Lee, Yang-Seok; Lee, Dong-Yeon; Cho, Man-Ho; Jeon, Jong-Seong; An, Gynheung

    2016-04-01

    The formation of body axes is the basis of morphogenesis during plant embryogenesis. We identified embryo-lethal mutants of rice (Oryza sativa) in which T-DNAs were inserted in OsMPK6 Embryonic organs were absent because their development was arrested at the globular stage. Similar to observations made with gle4, shootless, and organless, the osmpk6 mutations affected the initial step of cell differentiation. Expression of an apical-basal axis marker gene, OSH1, was reduced in the mutant embryos while that of the radial axes marker genes OsSCR and OsPNH1 was not detected. The signal for ROC1, a protodermal cell marker, was weak at the globular stage and gradually disappeared. Transcript levels of auxin and gibberellin biosynthesis genes were diminished in osmpk6 embryos. In addition, phytoalexin biosynthesis genes were down-regulated in osmpk6 and a major diterpene phytoalexin, momilactone A, did not accumulate in the mutant embryos. These results indicate that OsMPK6 begins to play a critical role during early embryogenesis, especially when the L1 radial axis is being formed. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  2. Establishment of embryonic shoot–root axis is involved in auxin and cytokinin response during Arabidopsis somatic embryogenesis

    Directory of Open Access Journals (Sweden)

    Ying Hua eSu

    2015-01-01

    Full Text Available Auxin and cytokinin signaling participates in regulating a large spectrum of developmental and physiological processes in plants. The shoots and roots of plants have specific and sometimes even contrary responses to these hormones. Recent studies have clearly shown that establishing the spatiotemporal distribution of auxin and cytokinin response signals is central for the control of shoot apical meristem (SAM induction in cultured tissues. However, little is known about the role of these hormones in root apical meristem (RAM initiation. Here, we found that the expression patterns of several regulatory genes critical for RAM formation were correlated with the establishment of the embryonic root meristem during somatic embryogenesis in Arabidopsis. Interestingly, the early expression of the WUS-RELATED HOMEOBOX 5 (WOX5 and WUSCHEL (WUS genes was induced and was nearly overlapped within the embryonic callus when somatic embryos (SEs could not be identified morphologically. Their correct expression was essential for RAM and SAM initiation and embryonic shoot–root axis establishment. Furthermore, we analyzed the auxin and cytokinin response during SE initiation. Notably, cytokinin response signals were detected in specific regions that were correlated with induced WOX5 expression and subsequent SE formation. Overexpression of the ARABIDOPSIS RESPONSE REGULATOR genes ARR7 and ARR15 (feedback repressors of cytokinin signaling, disturbed RAM initiation and SE induction. These results provide new information on auxin and cytokinin-regulated apical–basal polarity formation of shoot–root axis during somatic embryogenesis.

  3. A Modified Murine Embryonic Stem Cell Test for Evaluating the Teratogenic Effects of Drugs on Early Embryogenesis.

    Science.gov (United States)

    Yu, Ruoxing; Miyamura, Norio; Okamoto-Uchida, Yoshimi; Arima, Norie; Ishigami-Yuasa, Mari; Kagechika, Hiroyuki; Nishina, Hiroshi

    2015-01-01

    Mammalian fetal development is easily disrupted by exogenous agents, making it essential to test new drug candidates for embryotoxicity and teratogenicity. To standardize the testing of drugs that might be used to treat pregnant women, the U.S. Food and Drug Administration (FDA) formulated special grade categories, labeled A, B, C, D and X, that define the level of risk associated with the use of a specific drug during pregnancy. Drugs in categories (Cat.) D and X are those with embryotoxic and/or teratogenic effects on humans and animals. However, which stages of pregnancy are affected by these agents and their molecular mechanisms are unknown. We describe here an embryonic stem cell test (EST) that classifies FDA pregnancy Cat.D and Cat.X drugs into 4 classes based on their differing effects on primitive streak formation. We show that ~84% of Cat.D and Cat.X drugs target this period of embryogenesis. Our results demonstrate that our modified EST can identify how a drug affects early embryogenesis, when it acts, and its molecular mechanism. Our test may thus be a useful addition to the drug safety testing armamentarium.

  4. A Modified Murine Embryonic Stem Cell Test for Evaluating the Teratogenic Effects of Drugs on Early Embryogenesis.

    Directory of Open Access Journals (Sweden)

    Ruoxing Yu

    Full Text Available Mammalian fetal development is easily disrupted by exogenous agents, making it essential to test new drug candidates for embryotoxicity and teratogenicity. To standardize the testing of drugs that might be used to treat pregnant women, the U.S. Food and Drug Administration (FDA formulated special grade categories, labeled A, B, C, D and X, that define the level of risk associated with the use of a specific drug during pregnancy. Drugs in categories (Cat. D and X are those with embryotoxic and/or teratogenic effects on humans and animals. However, which stages of pregnancy are affected by these agents and their molecular mechanisms are unknown. We describe here an embryonic stem cell test (EST that classifies FDA pregnancy Cat.D and Cat.X drugs into 4 classes based on their differing effects on primitive streak formation. We show that ~84% of Cat.D and Cat.X drugs target this period of embryogenesis. Our results demonstrate that our modified EST can identify how a drug affects early embryogenesis, when it acts, and its molecular mechanism. Our test may thus be a useful addition to the drug safety testing armamentarium.

  5. The effects of microgravity on gametogenesis, fertilization, and early embryogenesis

    Science.gov (United States)

    Tan, X.

    Gametogenesis fertilization and early embryogenesis are crucial periods for normal development afterwards In past three decades many experiments have been conducted in space and in simulated weightlessness induced by clinostats to elucidate the issue Different animal species including Drosophila wasp shrimp fish amphibian mouse rats etc have been used for the study Oogenesis and spermatogenesis are affected by microgravity in different ways Some researches found that microgravity condition perturbed the process of oogenesis in many species A significant increased frequency of chromosomal non-disjunction was found in Drosophila females resulting the loss of chromosomes during meiosis and inhibition of cell division Studies on wasp showed a decreased hatchability and accumulation of unhatched eggs when the insects were exposed to spaceflight at different stages of oogenesis For experiments conducted on vertebrate animal models the results are somehow different however Microgravity has no significant effect for fish Medaka etc amphibian South African clawed toad Xenopus laevis or mammals mouse Spermatogenesis on the other hand is more significantly affected by microgravity condition Some researches indicated sperm are sensitive to changes in gravitational force and this sensitivity affects the ability of sperm to fertilize eggs Sperm swim with higher velocity in microgravity which is coupled with altered protein phosphorylation level in sperm under microgravity condition Microgravity also induced activation of the

  6. Embryogenesis, hatching and larval development of Artemia during orbital spaceflight

    Science.gov (United States)

    Spooner, B. S.; Debell, L.; Armbrust, L.; Guikema, J. A.; Metcalf, J.; Paulsen, A.

    1994-01-01

    Developmental biology studies, using gastrula-arrested cysts of the brine shrimp Artemia franciscana, were conducted during two flights of the space shuttle Atlantis (missions STS-37 and STS-43) in 1991. Dehydrated cysts were activated, on orbit, by addition of salt water to the cysts, and then development was terminated by the addition of fixative. Development took place in 5 ml syringes, connected by tubing to activation syringes, containing salt water, and termination syringes, containing fixative. Comparison of space results with simultaneous ground control experiments showed that equivalent percentages of naupliar larvae hatched in the syringes (40%). Thus, reactivation of development, completion of embryogenesis, emergence and hatching took place, during spaceflight, without recognizable alteration in numbers of larvae produced. Post-hatching larval development was studied in experiments where development was terminated, by introduction of fixative, 2 days, 4 days, and 8 days after reinitiation of development. During spaceflight, successive larval instars or stages, interrupted by molts, occurred, generating brine shrimp at appropriate larval instars. Naupliar larvae possessed the single naupliar eye, and development of the lateral pair of adult eyes also took place in space. Transmission electron microscopy revealed extensive differentiation, including skeletal muscle and gut endoderm, as well as the eye tissues. These studies demonstrate the potential value of Artemia for developmental biology studies during spa ceflight, and show that extensive degrees of development can take place in this microgravity environment.

  7. Expression pattern of protein kinase C δ during mouse embryogenesis

    Directory of Open Access Journals (Sweden)

    Carracedo Sergio

    2013-01-01

    Full Text Available Abstract Background The members of the protein kinase C (PKC family consist of serine/threonine kinases classified according to their regulatory domain. Those that belong to the novel PKC subfamily, such as PKCδ, are dependent on diacylglycerol but not Calcium when considering their catalytic activity. Although several studies have shown the importance of PKCδ in different cellular events in health and disease, the overall in vivo distribution of this PKC isoform during development is still lacking. Through Lac Z and antibody staining procedures, we show here the in vivo expression of PKCδ during mouse embryogenesis. Results Ganglia were the domains with most prominent expression of PKCδ in most of the stages analysed, although PKCδ could also be detected in heart and somites at earlier stages, and cartilage primordium and skin among other sites in older embryos. Conclusions The strong expression of PKCδ in ganglia during murine development shown in this study suggests a significant role of this isoform as well as redundancy with other PKCs within the nervous system, since PKCδ deficient mice develop normally.

  8. Excess caffeine exposure impairs eye development during chick embryogenesis

    Science.gov (United States)

    Ma, Zheng-lai; Wang, Guang; Cheng, Xin; Chuai, Manli; Kurihara, Hiroshi; Lee, Kenneth Ka Ho; Yang, Xuesong

    2014-01-01

    Caffeine has been an integral component of our diet and medicines for centuries. It is now known that over consumption of caffeine has detrimental effects on our health, and also disrupts normal foetal development in pregnant mothers. In this study, we investigated the potential teratogenic effect of caffeine over-exposure on eye development in the early chick embryo. Firstly, we demonstrated that caffeine exposure caused chick embryos to develop asymmetrical microphthalmia and induced the orbital bone to develop abnormally. Secondly, caffeine exposure perturbed Pax6 expression in the retina of the developing eye. In addition, it perturbed the migration of HNK-1+ cranial neural crest cells. Pax6 is an important gene that regulates eye development, so altering the expression of this gene might be the cause for the abnormal eye development. Thirdly, we found that reactive oxygen species (ROS) production was significantly increased in eye tissues following caffeine treatment, and that the addition of anti-oxidant vitamin C could rescue the eyes from developing abnormally in the presence of caffeine. This suggests that excess ROS induced by caffeine is one of the mechanisms involved in the teratogenic alterations observed in the eye during embryogenesis. In sum, our experiments in the chick embryo demonstrated that caffeine is a potential teratogen. It causes asymmetrical microphthalmia to develop by increasing ROS production and perturbs Pax6 expression. PMID:24636305

  9. Somatic embryogenesis from zygotic embryos of Euterpe oleracea Mart.

    Directory of Open Access Journals (Sweden)

    Ledo Ana da Silva

    2002-01-01

    Full Text Available The aim of this work was to study the morphogenetic responses of zygotic embryos of açai palm (Euterpe oleracea Mart. submitted to several conditions of in vitro culture. Several research experiments were conducted, in laboratory, using vegetable material collected from açai palm plants at Embrapa Amazon Oriental, Belém-PA, Brazil. It was possible to verify the expression of a direct, repetitive and no-synchronized model of somatic embryogenesis in mature zygotic embryos cultivated in primary MS medium supplemented with 2,4-D (339.36 muM and transferred to a secondary MS medium in the presence of NAA (0.537 muM and 2iP (12.30 muM. The conversion of somatic embryos into seedlings was reached after 210 days with the transfer of the cultures to a third medium with sucrose and mineral salts concentrations reduced to a half, without growth regulators.

  10. Changes of gentiopicroside synthesis during somatic embryogenesis in Gentiana macrophylla.

    Science.gov (United States)

    Chen, Li-Yu; Chen, Qian-Liang; Xu, Dan; Hao, Jian-Guo; Schläppi, Michael; Xu, Zi-Qin

    2009-12-01

    IN VITRO plant regeneration of Gentiana macrophylla Pall. and determination of gentiopicroside content during somatic embryogenesis are described in the present work. The highest percentage of embryogenic callus formation was observed in Murashige and Skoog (MS) medium supplemented with 1.0 mg/L 2,4-dichlorophenoxyacetic acid (2,4-D) and 1.0 mg/L 6-benzylaminopurine (BA). Calli were subcultured on MS medium containing 1.0 mg/L 2,4-D, 1.0 mg/L BA and 500 mg/L lactalbumin hydrolysate (LH) at intervals of 25 days. A higher frequency of somatic embryo maturation was achieved on MS medium containing B5 vitamins (MB) supplemented with different concentrations of 1-naphthaleneacetic acid (NAA) and BA than with a combination of NAA and kinetin (KT). Addition of AgNO(3) improved maturation of somatic embryos while thidiazuron (TDZ) promoted vitrification. The gentiopicroside contents of embryogenic calli and globular-, heart-, torpedo-, and cotyledon-shaped embryoids were determined by high-performance liquid chromatography (HPLC). Gentiopicroside was not detectable in embryogenic calli, but in all types of somatic embryos. The highest gentiopicroside content was observed in cotyledon-shaped embryoids, reaching more than 12 mg/g dry weight.

  11. Dielectrospectroscopic monitoring of early embryogenesis in single frog embryos

    Science.gov (United States)

    Asami, Koji; Irimajiri, Akihiko

    2000-11-01

    Dielectric spectroscopy has been used to monitor the early embryogenesis of frog (Xenopus laevis) eggs. The dielectric spectra of a single egg in suspension over the frequency range 10 Hz to 10 MHz were collected at various stages of its development. The uncleaved egg showed a dielectric dispersion with a narrow distribution of relaxation times. After the first cleavage, the dielectric spectra were mainly composed of two subdispersions. In the cleavage process, up to the morula stage, changes in the spectra were quantitatively simulated by the `cell-aggregate' model in which the embryo is regarded as a concentrated suspension of shell-spheres that correspond to the blastomeres (i.e. the cells within the embryo). In the stages from the morula to the blastula, the changes in the dielectric spectra were explained as due to a reduction in the size of the blastomere accompanied by an expansion of the blastocoel (i.e. the central cavity in the embryo) using the `vesicle-inclusion' model that is a cell aggregate covered with a less conducting shell corresponding to the outermost layer of tightly interconnected cells.

  12. Transcriptional analysis of late ripening stages of grapevine berry

    Directory of Open Access Journals (Sweden)

    Guillaumie Sabine

    2011-11-01

    Full Text Available Abstract Background The composition of grapevine berry at harvest is a major determinant of wine quality. Optimal oenological maturity of berries is characterized by a high sugar/acidity ratio, high anthocyanin content in the skin, and low astringency. However, harvest time is still mostly determined empirically, based on crude biochemical composition and berry tasting. In this context, it is interesting to identify genes that are expressed/repressed specifically at the late stages of ripening and which may be used as indicators of maturity. Results Whole bunches and berries sorted by density were collected in vineyard on Chardonnay (white cultivar grapevines for two consecutive years at three stages of ripening (7-days before harvest (TH-7, harvest (TH, and 10-days after harvest (TH+10. Microvinification and sensory analysis indicate that the quality of the wines made from the whole bunches collected at TH-7, TH and TH+10 differed, TH providing the highest quality wines. In parallel, gene expression was studied with Qiagen/Operon microarrays using two types of samples, i.e. whole bunches and berries sorted by density. Only 12 genes were consistently up- or down-regulated in whole bunches and density sorted berries for the two years studied in Chardonnay. 52 genes were differentially expressed between the TH-7 and TH samples. In order to determine whether these genes followed a similar pattern of expression during the late stages of berry ripening in a red cultivar, nine genes were selected for RT-PCR analysis with Cabernet Sauvignon grown under two different temperature regimes affecting the precocity of ripening. The expression profiles and their relationship to ripening were confirmed in Cabernet Sauvignon for seven genes, encoding a carotenoid cleavage dioxygenase, a galactinol synthase, a late embryogenesis abundant protein, a dirigent-like protein, a histidine kinase receptor, a valencene synthase and a putative S

  13. 3D early embryogenesis image filtering by nonlinear partial differential equations.

    Science.gov (United States)

    Krivá, Z; Mikula, K; Peyriéras, N; Rizzi, B; Sarti, A; Stasová, O

    2010-08-01

    We present nonlinear diffusion equations, numerical schemes to solve them and their application for filtering 3D images obtained from laser scanning microscopy (LSM) of living zebrafish embryos, with a goal to identify the optimal filtering method and its parameters. In the large scale applications dealing with analysis of 3D+time embryogenesis images, an important objective is a correct detection of the number and position of cell nuclei yielding the spatio-temporal cell lineage tree of embryogenesis. The filtering is the first and necessary step of the image analysis chain and must lead to correct results, removing the noise, sharpening the nuclei edges and correcting the acquisition errors related to spuriously connected subregions. In this paper we study such properties for the regularized Perona-Malik model and for the generalized mean curvature flow equations in the level-set formulation. A comparison with other nonlinear diffusion filters, like tensor anisotropic diffusion and Beltrami flow, is also included. All numerical schemes are based on the same discretization principles, i.e. finite volume method in space and semi-implicit scheme in time, for solving nonlinear partial differential equations. These numerical schemes are unconditionally stable, fast and naturally parallelizable. The filtering results are evaluated and compared first using the Mean Hausdorff distance between a gold standard and different isosurfaces of original and filtered data. Then, the number of isosurface connected components in a region of interest (ROI) detected in original and after the filtering is compared with the corresponding correct number of nuclei in the gold standard. Such analysis proves the robustness and reliability of the edge preserving nonlinear diffusion filtering for this type of data and lead to finding the optimal filtering parameters for the studied models and numerical schemes. Further comparisons consist in ability of splitting the very close objects which

  14. Identification and Isolation of Protein Markers Associated with Somatic Embryogenesis in Oil Palm

    Institute of Scientific and Technical Information of China (English)

    Chin Chiew Foan; Nguyen Thi Thuy Van

    2012-01-01

    Oil palm is an important oil bearing crop with the highest oil yield per hectare per year.About 90% of the world palm oil produced is used as vegetable oil while the remaining 10% is for non-food products such as oleochemicals and cosmetics.The high world demand for vegetable oil and increasingly the conversion of vegetable oil into biofuel,has prompted the oil palm industries to seek for high oil yielding seedlings.As oil palm has only a single meristem and full inbred lines were absent,propagation of elite oil palm through cutting or grafting is not possible.Clonal propagation through tissue culture offers a potential means for mass production of elite oil palm.Many oil palm laboratories have clonal propagated elite oil palm propagules through somatic embryogenesis.This study deployed 2DE coupled with LC MS/MS mass spectrometry to isolate protein markers associated with the initial stage of somatic embryogenesis i.e.callus proliferation.The isolated markers can then be used in early selection to screen for calli with high proliferation rate.Since amenability of explant is strongly correlated with maturity of the explants,proteomic analysis was focussed on isolating proteins associated with leaf maturity.Subsequently,comparisons were made on leaf with the same stage of maturity but with different callus proliferation rates.Quantitative analysis showed that there were a total of 67,77 and 4 protein spots to be present only in the young,medium and old leaves,respectively.While low and high proliferation leaves containing about the same amount of proteins,i.e.660 and 694 protein spots respectively.Interestingly,proteins with molecular weight of less than 25 kDa or had pl value lower than 5 were abundant only in leaves with high proliferation rate.Three spots with significant difference in expression by 2-fold among different growth stages were identified as protein subunits of ATP synthase (ATPE_LIRTU),Ribulose bisphosphate carboxylase (RBL_AMOTI) and a putative

  15. Structural analysis of the Pimelodus maculatus (Lacépède, 1803 embryogenesis (Siluriformes: Pimelodidae

    Directory of Open Access Journals (Sweden)

    Hellen Buzollo

    Full Text Available The fish embryonic development comprises the events between the egg fertilization up to larvae hatching, being useful for the identification of viable eggs in productivity and survival studies as well as in raising experiments of several species. The goal of the present study was to characterize the embryonic development of Pimelodus maculatus (Siluriformes; Pimelodidae. The embryogenesis was typical of teleosteans, but with differences in relation to other species such as duration of development, type of blastocoel, moment of somite segmentation among others. Six stages of embryonic development were defined: zygote, cleavage, blastula, gastrula, organogenesis (divided in phases: early segmentation and late segmentation and hatching with a period of incubation equal to 13 hours at 29 ºC and 17 hours at 25 ºC. The extruded oocytes presented a mean diameter of 812 µm before and 1066 µm after hydration. When fertilized, they presented a yellowish coloration and a gelatinous layer surrounding the chorion. The cleavage pattern is described as: 2; 4; 8 (4x2; 16 (4x4; 32 (4x8 and 64 (2x4x8 blastomeres up to morula phase (+64 cells. It was also possible to observe at this phase, the beginning of the formation of the yolk syncyctial layer (YSL. Afterwards, the blastula and gastrula stages followed. The end of gastrula was characterized by the formation of the yolk plug. Subsequently, the differentiation between cephalic and caudal regions began, along with the embryo elongation, structuring of optic, Kupffer's and otic vesicles besides a previously unidentified structure in the yolk syncyctial layer. The end of this stage is typified by the tail detachment. The late segmentation phase was distinguished by a free tail, presence of more than 30 somites, optic and otic vesicles, development of posterior intestine, pigmentation of cephalic and caudal regions of yolk sac and embryo growth. The recently-hatched larvae presented a primordial digestive tract

  16. Gfi1.1 regulates hematopoietic lineage differentiation during zebrafish embryogenesis

    Institute of Scientific and Technical Information of China (English)

    Wei Wei; Shuo Lin; Lu Wen; Peng Huang; Zheng Zhang; Yuanyuan Chen; An Xiao; Haigen Huang; Zuoyan Zhu; Bo Zhang

    2008-01-01

    Growth factor independence 1 (GFI1) is important for maturation of mammalian lymphocytes and neutrophils and maintenance of adult hematopoietic stem cells (HSCs).The role of GFl1 in embryonic hematopoiesis is less well characterized.Through an enhancer trap screen and bioinformatics analysis,we identified a zebrafish homolog of Gfi1 (named gfi1.1) and analyzed its function during embryonic development.Expression of both an endogenous gfi1.1 gene and a GFP reporter gene inserted near its genomic locus was detected in hematopoietic cells of zebrafish embryos.Morpholino (MO) knockdown of gfi1.1 reduced expression of scl,lmo2,c-myb,mpo,rag1,gata1 and hemoglobin alpha embryonic-1 (hbael),as well as the total amount of embryonic hemoglobin,but increased expression of pu.1 and l-plastin.Under the same conditions,MO injection did not affect the markers involved in vascular and pronephric development.Conversely,overexpression of gfi1.1 via mRNA injection enhanced expression of gatal but inhibited expression ofpu.1.These findings suggest that Gfi1.1 plays a critical role in regulating the balance of embryonic erythroid and myeloid lineage determination,and is also required for the differentiation of lymphocytes and granulocytes during zebrafish embryogenesis.

  17. Differential expression of the two Drosophila fos/kayak transcripts during oogenesis and embryogenesis.

    Science.gov (United States)

    Souid, Sami; Yanicostas, Constantin

    2003-05-01

    The Dfos/kayak gene encodes a bZIP protein, DFos, required in a large variety of differentiation and morphogenetic processes throughout Drosophila development. The recent availability of an expressed sequence tag (EST) sequence led us to identify a novel kay mRNA encoding a deduced DFos isoform showing a specific NH(2)-terminal region. To gain further insight into the function and the regulation of this gene, we have investigated the expression pattern of the two kay mRNA isoforms, kay-RA and kay-RB, during oogenesis and embryogenesis by whole-mount in situ hybridization. Results show that, although the two kay RNA isoforms display fully distinct patterns of transcription during oogenesis, they show partially overlapping expression profiles in embryos. These data reveal a previously unsuspected level of complexity in the regulation of the expression of the kay gene. In addition, they suggest a possible requirement for this gene in the invagination processes during early gastrula stages.

  18. SWATH-MS data of Drosophila melanogaster proteome dynamics during embryogenesis

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    Bertrand Fabre

    2016-12-01

    Full Text Available Embryogenesis is one of the most important processes in the life of an animal. During this dynamic process, progressive cell division and cellular differentiation are accompanied by significant changes in protein expression at the level of the proteome. However, very few studies to date have described the dynamics of the proteome during the early development of an embryo in any organism. In this dataset, we monitor changes in protein expression across a timecourse of more than 20 h of Drosophila melanogaster embryonic development. Mass-spectrometry data were produced using a SWATH acquisition mode on a Sciex Triple-TOF 6600. A spectral library built in-house was used to analyse these data and more than 1950 proteins were quantified at each embryonic timepoint. The files presented here are a permanent digital map and can be reanalysed to test against new hypotheses. The data have been deposited with the ProteomeXchange Consortium with the dataset identifier PRIDE: PXD0031078.

  19. Anatomical Study of Somatic Embryogenesis in Glycine max (L. Merrill

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    Juliana Aparecida Fernando

    2002-09-01

    Full Text Available A comparative anatomical analysis of somatic embryogenesis in two soybean (Glycine max (L. Merrill genotypes was carried out. The somatic embryos were originated from cotyledonary explants obtained from immature zygotic embryos. The medium used for somatic embryogenesis induction was Murashige and Skoog, 1962, salts and Gamborg et al., 1968, vitamins (MSB supplemented with 0.8 mg.L-1 of 2,4-D for genotype PI 123439 and 40 mg.L-1 of 2,4-D for ‘Williams 82’. Globular structures, constituted by meristematic cells, originated from subepidermal cell divisions of the cotyledonary mesophyll. In PI 123439, the globular structures presented tracheary differentiation among meristematic cells and they could follow distinct morphogenetic process depending on their location along the explant. For ‘Williams 82’ it was observed globular structures along the cotyledonary explant surface. They gave rise to somatic embryos. These embryos showed different morphologies and they were classified based on their shape and number of cotyledons. The ability of these morphological types to convert to plantlets was discussed.Realizou-se uma análise anatômica comparativa da embriogênese somática em dois genótipos de soja (Glycine max (L. Merrill. Os embriões somáticos foram obtidos a partir de explantes cotiledonares excisados de embriões zigóticos imaturos do genótipo PI 123439, adaptado às condições tropicais, e ‘Williams 82’. O meio utilizado para indução da embriogênese somática constituiu-se de sais de Murashige e Skoog,1962, e vitaminas de Gamborg et al., 1968 (MSB suplementado com 0,8 mg.L-1 de 2,4-D (PI 123439 e 40 mg.L-1 (‘Williams 82’. Estruturas globulares originaram-se a partir de divisões celulares nas camadas subepidérmicas do mesofilo cotiledonar e foram constituídas por células meristemáticas. No genótipo PI 123439, as estruturas globulares apresentaram diferenciação traqueal entre as células meristemáticas e

  20. Altered A-to-I RNA Editing in Human Embryogenesis

    Science.gov (United States)

    Mandel, Rachel; Ziskind, Anna; Nahor, Irit; Safran, Michal; Osenberg, Sivan; Sherf, Ofra; Rechavi, Gideon; Itskovitz-Eldor, Joseph

    2012-01-01

    Post-transcriptional events play an important role in human development. The question arises as to whether Adenosine to Inosine RNA editing, catalyzed by the ADAR (Adenosine Deaminase acting on RNA) enzymes, differs in human embryogenesis and in adulthood. We tested the editing of various target genes in coding (FLNA, BLCAP, CYFIP2) and non-coding sequences at their Alu elements (BRCA1, CARD11, RBBP9, MDM4, FNACC), as well as the transcriptional levels of the ADAR1 enzymes. This analysis was performed on five fetal and adult human tissues: brain, heart, liver, kidney, and spleen, as well as on human embryonic stem cells (hESCs), which represent the blastocyst stage in early human development. Our results show substantially greater editing activity for most adult tissue samples relative to fetal ones, in six of the eight genes tested. To test the effect of reduced A-to-I RNA editing activity in early human development we used human embryonic stem cells (hESCs) as a model and tried to generate hESC clones that overexpress the ADAR1–p110 isoform. We were unable to achieve overexpression of ADAR1–p110 by either transfection or lentiviral infection, though we easily generated hESC clones that expressed the GFP transgene and overexpressed ADAR1-p110 in 293T cells and in primary human foreskin fibroblast (HFF) cells. Moreover, in contrast to the expected overexpression of ADAR1-p110 protein following its introduction into hESCs, the expression levels of this protein decreased dramatically 24–48 hr post infection. Similar results were obtained when we tried to overexpress ADAR1-p110 in pluripotent embryonal carcinoma cells. This suggests that ADAR1 protein is substantially regulated in undifferentiated pluripotent hESCs. Overall, our data suggest that A-to-I RNA editing plays a critical role during early human development. PMID:22859999

  1. Effects of light quality on somatic embryogenesis in Araujia sericifera.

    Science.gov (United States)

    Torné, Josep M.; Moysset, Luisa; Santos, Mireya; Simón, Esther

    2001-03-01

    The effects of photoperiod, light quality and end-of-day (EOD) phytochrome photoconversion on somatic embryogenesis (SE) of Araujia sericifera petals have been studied. Petals from immature flowers were cultured under 8- and 16-h photoperiods using Gro-lux fluorescent lamps. The photon fluence rate was 90-100 µmol m-2 s-1 and the red (R):far-red (FR) ratio was 98. R, FR, R followed by FR (R-FR) and FR followed by R (FR-R) light treatments were applied for 3 weeks at the end of the photoperiods. In a set of experiments, DL-alpha-difluoromethylarginine (DFMA) or methylglyoxal bis(guanylhydrazone) (MGBG), both inhibitors of polyamine biosynthesis, were added to the culture medium in order to study the involvement of polyamine metabolism. The level of SE was the same in long (LD) and short (SD) days. Thus, the light effect was accomplished after 8 h. All EOD treatments that decreased the Pfr level inhibited SE when applied after SD, but not after LD. The FR-R treatment after LD caused an additional stimulatory effect on SE, even in the presence of polyamine inhibitors. DFMA inhibited SE in both SD and LD, but MGBG did not modify SE in either SD or LD. The R, FR and R-FR treatments did not alter the level of SE when applied after LD in the presence of DFMA or MGBG. However, these treatments decreased SE after SD when the medium contained polyamine inhibitors. Our results suggest that Gro-lux lamps, which produce an extremely high R:FR ratio, promote SE in A. sericifera and a timing response to phytochrome photoconversion during photoperiodic induction. Thus, our data corroborate the involvement of phytochromes and polyamines in SE in A. sericifera, which responded as a light-dominant long-day plant.

  2. Altered A-to-I RNA editing in human embryogenesis.

    Directory of Open Access Journals (Sweden)

    Ronit Shtrichman

    Full Text Available Post-transcriptional events play an important role in human development. The question arises as to whether Adenosine to Inosine RNA editing, catalyzed by the ADAR (Adenosine Deaminase acting on RNA enzymes, differs in human embryogenesis and in adulthood. We tested the editing of various target genes in coding (FLNA, BLCAP, CYFIP2 and non-coding sequences at their Alu elements (BRCA1, CARD11, RBBP9, MDM4, FNACC, as well as the transcriptional levels of the ADAR1 enzymes. This analysis was performed on five fetal and adult human tissues: brain, heart, liver, kidney, and spleen, as well as on human embryonic stem cells (hESCs, which represent the blastocyst stage in early human development. Our results show substantially greater editing activity for most adult tissue samples relative to fetal ones, in six of the eight genes tested. To test the effect of reduced A-to-I RNA editing activity in early human development we used human embryonic stem cells (hESCs as a model and tried to generate hESC clones that overexpress the ADAR1-p110 isoform. We were unable to achieve overexpression of ADAR1-p110 by either transfection or lentiviral infection, though we easily generated hESC clones that expressed the GFP transgene and overexpressed ADAR1-p110 in 293T cells and in primary human foreskin fibroblast (HFF cells. Moreover, in contrast to the expected overexpression of ADAR1-p110 protein following its introduction into hESCs, the expression levels of this protein decreased dramatically 24-48 hr post infection. Similar results were obtained when we tried to overexpress ADAR1-p110 in pluripotent embryonal carcinoma cells. This suggests that ADAR1 protein is substantially regulated in undifferentiated pluripotent hESCs. Overall, our data suggest that A-to-I RNA editing plays a critical role during early human development.

  3. Cloning and expression of embryogenesis-regulating genes in Araucaria angustifolia (Bert. O. Kuntze (Brazilian Pine

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio Schlögl

    2012-01-01

    Full Text Available Angiosperm and gymnosperm plants evolved from a common ancestor about 300 million years ago. Apart from morphological and structural differences in embryogenesis and seed origin, a set of embryogenesis-regulating genes and the molecular mechanisms involved in embryo development seem to have been conserved alike in both taxa. Few studies have covered molecular aspects of embryogenesis in the Brazilian pine, the only economically important native conifer in Brazil. Thus eight embryogenesis-regulating genes, viz.,ARGONAUTE 1, CUP-SHAPED COTYLEDON 1, WUSCHEL-related WOX, S-LOCUS LECTIN PROTEIN KINASE, SCARECROW-like, VICILIN 7S, LEAFY COTYLEDON 1, and REVERSIBLE GLYCOSYLATED POLYPEPTIDE 1, were analyzed through semiquantitative RT-PCR during embryo development and germination. All the eight were found to be differentially expressed in the various developmental stages of zygotic embryos, seeds and seedling tissues. To our knowledge, this is the first report on embryogenesis-regulating gene expression in members of the Araucariaceae family, as well as in plants with recalcitrant seeds.

  4. Cloning and expression of embryogenesis-regulating genes in Araucaria angustifolia (Bert.) O. Kuntze (Brazilian Pine)

    Science.gov (United States)

    Schlögl, Paulo Sérgio; dos Santos, André Luis Wendt; Vieira, Leila do Nascimento; Floh, Eny Iochevet Segal; Guerra, Miguel Pedro

    2012-01-01

    Angiosperm and gymnosperm plants evolved from a common ancestor about 300 million years ago. Apart from morphological and structural differences in embryogenesis and seed origin, a set of embryogenesis-regulating genes and the molecular mechanisms involved in embryo development seem to have been conserved alike in both taxa. Few studies have covered molecular aspects of embryogenesis in the Brazilian pine, the only economically important native conifer in Brazil. Thus eight embryogenesis-regulating genes, viz., ARGONAUTE 1, CUP-SHAPED COTYLEDON 1, WUSCHEL-related WOX, S-LOCUS LECTIN PROTEIN KINASE, SCARECROW-like, VICILIN 7S, LEAFY COTYLEDON 1, and REVERSIBLE GLYCOSYLATED POLYPEPTIDE 1, were analyzed through semi-quantitative RT-PCR during embryo development and germination. All the eight were found to be differentially expressed in the various developmental stages of zygotic embryos, seeds and seedling tissues. To our knowledge, this is the first report on embryogenesis-regulating gene expression in members of the Araucariaceae family, as well as in plants with recalcitrant seeds. PMID:22481892

  5. Influence of abscisic acid and sucrose on somatic embryogenesis in Cactus Copiapoa tenuissima Ritt. forma mostruosa.

    Science.gov (United States)

    Lema-Rumińska, J; Goncerzewicz, K; Gabriel, M

    2013-01-01

    Having produced the embryos of cactus Copiapoa tenuissima Ritt. forma monstruosa at the globular stage and callus, we investigated the effect of abscisic acid (ABA) in the following concentrations: 0, 0.1, 1, 10, and 100  μ M on successive stages of direct (DSE) and indirect somatic embryogenesis (ISE). In the indirect somatic embryogenesis process we also investigated a combined effect of ABA (0, 0.1, 1  μ M) and sucrose (1, 3, 5%). The results showed that a low concentration of ABA (0-1  μ M) stimulates the elongation of embryos at the globular stage and the number of correct embryos in direct somatic embryogenesis, while a high ABA concentration (10-100  μ M) results in growth inhibition and turgor pressure loss of somatic embryos. The indirect somatic embryogenesis study in this cactus suggests that lower ABA concentrations enhance the increase in calli fresh weight, while a high concentration of 10  μ M ABA or more changes calli color and decreases its proliferation rate. However, in the case of indirect somatic embryogenesis, ABA had no effect on the number of somatic embryos and their maturation. Nevertheless, we found a positive effect of sucrose concentration for both the number of somatic embryos and the increase in calli fresh weight.

  6. Label-Free Quantitative Proteomics of Embryogenic and Non-Embryogenic Callus during Sugarcane Somatic Embryogenesis.

    Directory of Open Access Journals (Sweden)

    Angelo Schuabb Heringer

    Full Text Available The development of somatic cells in to embryogenic cells occurs in several stages and ends in somatic embryo formation, though most of these biochemical and molecular changes have yet to be elucidated. Somatic embryogenesis coupled with genetic transformation could be a biotechnological tool to improve potential crop yields potential in sugarcane cultivars. The objective of this study was to observe somatic embryo development and to identify differentially expressed proteins in embryogenic (E and non-embryogenic (NE callus during maturation treatment. E and NE callus were cultured on maturation culture medium supplemented with different concentrations (0.0, 0.75, 1.5 and 2.0 g L(-1 of activated charcoal (AC. Somatic embryo formation and differential protein expression were evaluated at days 0 and 21 using shotgun proteomic analyses. Treatment with 1.5 g L(-1 AC resulted in higher somatic embryo maturation rates (158 somatic embryos in 14 days in E callus but has no effect in NE callus. A total of 752 co-expressed proteins were identified through the SUCEST (The Sugarcane EST Project, including many housekeeping proteins. E callus showed 65 exclusive proteins on day 0, including dehydrogenase, desiccation-related protein, callose synthase 1 and nitric oxide synthase. After 21 days on maturation treatment, 14 exclusive proteins were identified in E callus, including catalase and secreted protein. NE callus showed 23 exclusive proteins on day 0 and 10 exclusive proteins after 21 days on maturation treatment, including many proteins related to protein degradation. The induction of maturation leads to somatic embryo development, which likely depends on the expression of specific proteins throughout the process, as seen in E callus under maturation treatment. On the other hand, some exclusive proteins can also specifically prevent of somatic embryos development, as seen in the NE callus.

  7. Novel Mitochondria-Targeted Heat-Soluble Proteins Identified in the Anhydrobiotic Tardigrade Improve Osmotic Tolerance of Human Cells

    OpenAIRE

    Sae Tanaka; Junko Tanaka; Yoshihiro Miwa; Horikawa, Daiki D.; Toshiaki Katayama; Kazuharu Arakawa; Atsushi Toyoda; Takeo Kubo; Takekazu Kunieda

    2015-01-01

    Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called "anhydrobiosis". Late Embryogenesis Abundant (LEA) proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble) and SAHS (Secretory Abundant Heat Soluble) proteins, which are se...

  8. Effect of exogenous cytokinins on growth and somatic embryogenesis in anise cells (Pimpinella anisum L.).

    Science.gov (United States)

    Ernst, D; Oesterhelt, D

    1984-05-01

    A cell culture of anise was grown in the presence or absence of 2,4-dichlorophenoxyacetic acid (2,4-D). Application of isopentenyladenine or isopentenyladenosine (4·10(-8) to 4·10(-7) M) to the proembryonic culture (+2,4-D) yielded an increase of the cell density, in contrast to a proembryonic culture grown without exogenous application of cytokinins. Embryogenesis was induced by transferring the cells to a hormone-free medium. Embryo development was promoted by isopentenyladenine and isopentenyladenosine (5·10(-8) to 5·10(-7) M), higher concentrations (5·10(-6) M) inhibited embryogenesis. The effect of cytokinins on embryogenesis was only promotive until the third day of culture, i.e. coincident with cell growth rather than differentiation.

  9. POLYPHENOLS DISTRIBUTION AND RESERVE SUBSTANCES ANALYSIS IN CACAO SOMATIC EMBRYOGENESIS

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    Adriana María Gallego Rúa

    2016-04-01

    Full Text Available ABSTRACTIn order to understand the causes of lack of regeneration in cacao somatic embryos, two cacao varieties with different responses to regeneration potential were described based on their capacity to store different compounds. It is well known that seed reserves play a central role in the regenerative capability of somatic embryos; thus, we followed histochemical changes and reserve fluctuations of proteins, polysaccharides and polyphenols during somatic embryogenesis (SE in the two cacao varieties. The study showed that, in somatic embryos of the regenerating variety, polyphenols were localized mainly in the periphery of the embryo (epidermal cells and proteins were the main storage substance in the embryo expression medium, while the non-regenerating variety had a high presence of polysaccharides with random distribution of polyphenols at the end of the embryo induction step.Análisis de distribución de polifenoles y sustancias de reserva en embriogénesis somática de cacaoRESUMENDos variedades de cacao con diferentes respuestas a la regeneración fueron descritas en función de su capacidad para almacenar diferentes compuestos, con el fin de aproximarse al entendimiento de las causas de la falta de regeneración en embriones somáticos de cacao. Es bien sabido que las reservas de semillas desempeñan un papel central en la capacidad de regeneración de embriones somáticos; por tanto, se realizó un seguimiento de cambios histoquímicos y fluctuaciones de reserva de proteínas, polisacáridos y polifenoles durante la embriogénesis somática (SE en dos variedades de cacao. El estudio mostró que, en los embriones somáticos de la variedad regenerante, los polifenoles se localizaron principalmente en la periferia del embrión (células de la epidermis y las proteínas fueron el componente principal de almacenamiento en el medio de expresión de embriones, mientras que la variedad no regenerante tenía una alta presencia de polisac

  10. Zebrafish foxo3b negatively regulates canonical Wnt signaling to affect early embryogenesis.

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    Xun-wei Xie

    Full Text Available FOXO genes are involved in many aspects of development and vascular homeostasis by regulating cell apoptosis, proliferation, and the control of oxidative stress. In addition, FOXO genes have been showed to inhibit Wnt/β-catenin signaling by competing with T cell factor to bind to β-catenin. However, how important of this inhibition in vivo, particularly in embryogenesis is still unknown. To demonstrate the roles of FOXO genes in embryogenesis will help us to further understand their relevant physiological functions. Zebrafish foxo3b gene, an orthologue of mammalian FOXO3, was expressed maternally and distributed ubiquitously during early embryogenesis and later restricted to brain. After morpholino-mediated knockdown of foxo3b, the zebrafish embryos exhibited defects in axis and neuroectoderm formation, suggesting its critical role in early embryogenesis. The embryo-developmental marker gene staining at different stages, phenotype analysis and rescue assays revealed that foxo3b acted its role through negatively regulating both maternal and zygotic Wnt/β-catenin signaling. Moreover, we found that foxo3b could interact with zebrafish β-catenin1 and β-catenin2 to suppress their transactivation in vitro and in vivo, further confirming its role relevant to the inhibition of Wnt/β-catenin signaling. Taken together, we revealed that foxo3b played a very important role in embryogenesis and negatively regulated maternal and zygotic Wnt/β-catenin signaling by directly interacting with both β-catenin1 and β-catenin2. Our studies provide an in vivo model for illustrating function of FOXO transcription factors in embryogenesis.

  11. Somatic embryogenesis ofCyclamen persicum Mill. 'Anneke' from aseptic seedlings.

    Science.gov (United States)

    Takamura, T; Miyajima, I; Matsuo, E

    1995-01-01

    InCyclamen persicum 'Anneke', explants from the various vegetative organs of aseptic seedling formed embryoids. The optimal responses were recorded in Murashige and Skoog (MS) medium enriched with 5.0µM 2,4-dichlorophenoxyacetic acid (2,4-D), 0.5µM kinetin and 3-6% sucrose. Embryogenesis was enhanced at higher temperature of 25-30°C. On the other hand, light inhibited embryogenesis. Histological and morphological studies confirmed that the embryoids were indeed somatic embryos.

  12. Analysis of poly(A + RNA distribution during maize somatic embryogenesis using digoxigenated oligo-dT probes

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    R. Bimal

    2014-01-01

    Full Text Available The pattern of total transcription activity in terms of steady state levels of poly(A+ containing mRNA during callus initiation and somatic embryogenesis in a high (A188 and a low (A632 embryogenic line of maize was analyzed using digoxigenin labelled oligo-dT probes. A gradual increase and a preferential accumulation of label was observed in both lines, differing temporally up to 4 days in culture. In the A188 line of maize the callus gave rise to somatic embryos. The globular embryos showed less label than the callus; this labelling was mostly present in the basal part of the embryos. At a later stage upper embryogenic and lower non-embryogenic layers were observed in the A188 callus, showing conspicuous differences in the amount of label. In the late globular stage the poly(A+ RNA signals were seen all over the embryo but at the junction of the suspensor and the callus tissue no label was observed.

  13. Nuclear glycogen synthase kinase-3 {beta} (GSK-3) in Rhipicephalus (Boophilus) microplus tick embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Mentzingen, Leticia; Andrade, Josiana G. de; Logullo, Carlos [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Biociencias e Biotecnologia. Lab. de Quimica e Funcao de Proteinas e Peptideos (LQFPP); Andrade, Caroline P. de; Vaz Junior, Itabajara [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Centro de Biotecnologia

    2008-07-01

    Full text: Glycogen synthase kinase-3 (GSK3) is recognized as a key component of a large number of cellular processes and diseases. Several mechanisms play a part in controlling the actions of GSK3, including phosphorylation, protein complex formation, and subcellular distribution. Recent observations point to functions for phosphorylases several transcription factors in the nucleus. Also, GSK3b participate of the canonical W nt signalling pathway, which has been studied intensively in embryonic and cancer cells. Like in many other signaling pathways, most components in W nt signal transduction were highly conserved during the evolution. More than 40 proteins have been reported to be phosphorylated by GSK3, including over a dozen transcription factors. Although the mechanisms regulating GSK3 are not fully understood, precise control appears to be achieved by a combination of phosphorylation, localization, and interactions with GSK3-binding proteins. Although GSK3 is traditionally considered a cytosolic protein, it is also present in nuclei. Nuclear GSK3 is particularly interesting because of the many transcription factors that it regulates enabling GSK3 to influence many signaling pathways that converge on these transcription factors, thereby regulating the expression of many genes. Our group identified that GSK-3 {beta} could be detected in different stage eggs of R. micro plus. In this work we detected the GSK-3 in isolated nuclear fraction from the egg homogenates of R. micro plus by western-blot analysis, using anti-GSK- 3 {beta} antibodies. The enzyme activity was also detected radiochemically throughout embryogenesis in same fraction. The GSK-3 activity was inhibiting by using SB 216763 (selective molecule inhibitors of GSK-3). Taken together our results suggest that GSK-3 {beta} isoform probably is involved in gene transcription factors during R. micro plus embryo development.

  14. Developmental localization and the role of hydroxyproline rich glycoproteins during somatic embryogenesis of banana (Musa spp. AAA

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    Menzel Diedrik

    2011-02-01

    Full Text Available Abstract Background Hydroxyproline rich glycoproteins (HRGPs are implicated to have a role in many aspects of plant growth and development but there is limited knowledge about their localization and function during somatic embryogenesis of higher plants. In this study, the localization and function of hydroxyproline rich glycoproteins in embryogenic cells (ECs and somatic embryos of banana were investigated by using immunobloting and immunocytochemistry with monoclonal JIM11 and JIM20 antibodies as well as by treatment with 3,4-dehydro-L-proline (3,4-DHP, an inhibitor of extensin biosynthesis, and by immunomodulation with the JIM11 antibody. Results Immunofluorescence labelling of JIM11 and JIM20 hydroxyproline rich glycoprotein epitopes was relatively weak in non-embryogenic cells (NECs, mainly on the edge of small cell aggregates. On the other hand, hydroxyproline rich glycoprotein epitopes were found to be enriched in early embryogenic cells as well as in various developmental stages of somatic embryos. Embryogenic cells (ECs, proembryos and globular embryos showed strong labelling of hydroxyproline rich glycoprotein epitopes, especially in their cell walls and outer surface layer, so-called extracellular matrix (ECM. This hydroxyproline rich glycoprotein signal at embryo surfaces decreased and/or fully disappeared during later developmental stages (e.g. pear-shaped and cotyledonary stages of embryos. In these later developmental embryogenic stages, however, new prominent hydroxyproline rich glycoprotein labelling appeared in tri-cellular junctions among parenchymatic cells inside these embryos. Overall immunofluorescence labelling of late stage embryos with JIM20 antibody was weaker than that of JIM11. Western blot analysis supported the above immunolocalization data. The treatment with 3,4-DHP inhibited the development of embryogenic cells and decreased the rate of embryo germination. Embryo-like structures, which developed after 3,4-DHP

  15. Imaging of polarity during zygotic and somatic embryogenesis of carrot (Daucus carota L.).

    NARCIS (Netherlands)

    Timmers, A.C.J.

    1993-01-01

    In this thesis a study of the regulation of coordinated growth and the development of polarity during embryogenesis of carrot, Daucus carota L., is described. To this end, several microscopical techniques were used, such as light microscopy, fluorescence microscopy, confocal scanning laser microscop

  16. Induction of embryogenesis in microspores and pollen of Brassica napus L. cv. Topas.

    NARCIS (Netherlands)

    Hause, B.; Hause, G.

    1996-01-01

    Artificial systems to produce plant embryos are important tools for basic research as well as for plant breeding. It is possible to produce large amounts of embryos by methods like somatic embryogenesis or embryogenic microspore cultures. Such high amounts of embryos, which are easier to handle than

  17. Embryogenesis from isolated microspores of tulip : towards developing F1 hybrid varieties

    NARCIS (Netherlands)

    Custers, J.B.M.; Ennik, E.; Eikelboom, W.; Dons, J.J.M.; Lookeren Campagne, van M.M.

    1997-01-01

    This report describes advances in the technique of embryogenesis from tulip microspores in culture. High temperature pretreatment (32°C) of bulbs, which contain fully developed inflorescences, had a positive effect on the production of microspore embryos. The pretreatment shortened the time for

  18. The Arabidopsis kinase-associated protein phosphatase controls internalization of the somatic embryogenesis receptor kinase 1

    NARCIS (Netherlands)

    Shah, K.; Russinova, E.; Gadella, T.W.J.; Willemse, J.; Vries, de S.C.

    2002-01-01

    The AtSERK1 protein is a plasma membrane-located LRR receptor-like serine threonine kinase that is transiently expressed during plant embryogenesis. Our results show that AtSERK1 interacts with the kinase-associated protein phosphatase (KAPP) in vitro. The kinase interaction (KI) domain of KAPP does

  19. The Pesticide Malathion Disrupts "Xenopus" and Zebrafish Embryogenesis: An Investigative Laboratory Exercise in Developmental Toxicology

    Science.gov (United States)

    Chemotti, Diana C.; Davis, Sarah N.; Cook, Leslie W.; Willoughby, Ian R.; Paradise, Christopher J.; Lom, Barbara

    2006-01-01

    Malathion is an organophosphorus insecticide, which is often sprayed to control mosquitoes. When applied to aquatic habitats, malathion can also influence the embryogenesis of non-target organisms such as frogs and fish. We modified the frog embryo teratogen assay in "Xenopus" (FETAX), a standard toxicological assay, into an investigative…

  20. On the Origin of SERKs: Bioinformatics Analysis of the Somatic Embryogenesis Receptor Kinases

    NARCIS (Netherlands)

    Toorn, aan den M.; Albrecht, C.; Vries, de S.C.

    2015-01-01

    Somatic embryogenesis receptor-like kinases (SERKs) are leucine-rich repeat receptor-like kinases involved in several, seemingly unrelated, plant-signaling pathways. In Arabidopsis thaliana, functional and genetic analysis of four SERK proteins has indicated that they are only partly redundant; thei

  1. High-frequency plant regeneration through cyclic secondary somatic embryogenesis in black pepper (Piper nigrum L.).

    Science.gov (United States)

    Nair, R Ramakrishnan; Dutta Gupta, S

    2006-01-01

    A high-frequency plantlet regeneration protocol was developed for black pepper (Piper nigrum L.) through cyclic secondary somatic embryogenesis. Secondary embryos formed from the radicular end of the primary somatic embryos which were originally derived from micropylar tissues of germinating seeds on growth regulator-free SH medium in the absence of light. The process of secondary embryogenesis continued in a cyclic manner from the root pole of newly formed embryos resulting in clumps of somatic embryos. Strength of the medium and sucrose concentration influenced the process of secondary embryogenesis and fresh weight of somatic embryo clumps. Full-strength SH medium supplemented with 1.5% sucrose produced significantly higher fresh weight and numbers of secondary somatic embryos while 3.0 and 4.5% sucrose in the medium favored further development of proliferated embryos into plantlets. Ontogeny of secondary embryos was established by histological analysis. Secondary embryogenic potential was influenced by the developmental stage of the explanted somatic embryo and stages up to "torpedo" were more suitable. A single-flask system was standardized for proliferation, maturation, germination and conversion of secondary somatic embryos in suspension cultures. The system of cyclic secondary somatic embryogenesis in black pepper described here represents a permanent source of embryogenic material that can be used for genetic manipulations of this crop species.

  2. Late-Onset Asthma

    DEFF Research Database (Denmark)

    Ulrik, Charlotte Suppli

    2017-01-01

    Late-onset asthma is common, associated with poor outcome, underdiagnosed and undertreated, possibly due to the modifying effect of ageing on disease expression. Although the diagnostic work-up in elderly individuals suspected of having asthma follows the same steps as in younger individuals (case......, to objectively confirm asthma. If necessary, a trial of oral or inhaled corticosteroid might be necessary. Asthma can be diagnosed when increased airflow variability is identified in a symptomatic patient, and if the patient does not have a history of exposure, primarily smoking, known to cause chronic...... obstructive pulmonary disease, the diagnosis is asthma even if the patient does not have fully reversible airflow obstruction. Pharmacological therapy in patients with late-onset asthma follows international guidelines, including treatment with the lowest effective dose of inhaled corticosteroid to minimize...

  3. Germ band retraction as a landmark in glucose metabolism during Aedes aegypti embryogenesis

    Directory of Open Access Journals (Sweden)

    Logullo Carlos

    2010-02-01

    Full Text Available Abstract Background The mosquito A. aegypti is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of A. aegypty life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during A. aegypti embryogenesis are unknown. Results Glucose metabolism was investigated throughout Aedes aegypti (Diptera embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE and germ band retraction (GBr, 24 HAE may be considered landmarks regarding glucose 6-phosphate (G6P destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP, of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK and pyruvate kinase (PK activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3 activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis. Conclusions The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose

  4. Somatic embryogenesis in wild relatives of cotton (Gossypium Spp.)

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Wild cotton species can contribute a valuable gene pool for agronomically desirable cultivated tetraploid cultivars. In order to exploit diploid cotton a regeneration system is required to achieve transformation based goals. The present studies aimed at optimizing the conditions for regeneration of local varieties as well as wild species of cotton. Different callus induction media were tested with varying concentrations of hormones in which sucrose was used as nutritional source. Different explants (hypocotyls, cotyledon, root) were used to check the regeneration of both local cotton plants and wild relatives using T & G medium,BAP medium, CIM medium, EMMS medium, and cell suspension medium. Different stages of embryogenicity such as early torpedo stage, late torpedo stage, heart stage, globular stage and cotyledonary stage were observed in wild relatives of cotton. The results of this study pave the way for establishing future transformation methods.

  5. Exploring Late Globalization

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2016-01-01

    The purpose of this viewpoint paper is to motivate a program of research on late globalization, a program that could eventually lead to one or more significant theories of late globalization. The paper explores the phenomenon of late globalization as well as the idea of “late” by drawing on sparse...... literature on late globalization from sociocultural and economic perspectives. It illustrates in a vignette the character and features of late globalization observable in the withdrawal from foreign locations or deinternationalization of universities, as late globalizing entitis. The paper discusses...... the range of constructs around the core idea of late globalization, generating questions for future work in a late globalization research program....

  6. Effect of Different Hormone Combinations on Somatic Embryogenesis in Cotton Cultivar Xinluzao 33(Gossypium hirsutum L.)

    Institute of Scientific and Technical Information of China (English)

    Panpan MA; Zongming XIE; Quansheng LI; Yousheng TIAN; Youzhong LI

    2015-01-01

    Objective] This study was conducted to evaluate the efficiency of somatic embryogenesis and plant regeneration for an upland cotton cultivar Xinluzao33 under the induction of different hormone combinations and thus to determine the optimal hormone combination. [Method] Cal i of Xinluzao33 (Gossypium hirsutum L.) were in-duced from seedling hypocotyl tissue by a range of DK and BK combinations. Em-bryogenic cal i and embryos were induced on cal us-inducing medium (CIM) without any hormones. Cal us appearance and quality were compared to determine which medium was the optimal for cal us induction. Embryogenesis ratio was calculated to determine which medium was the best for somatic embryogenesis and plant regen-eration. [Result] Cal us induction rate was 100% in al the 12 hormone combinations. The cal i were yel ow or kel y, and their texture was loose or soft under low con-centrations of DK combinations, green or white, variably compact under high con-centrations of DK combinations. The cal i induced by BK combinations were kel y or green, covering creamy white substance. The best medium for cal us induction was DK6 (0.05 mg/L 2, 4-D and 0.10 mg/L KT). Embryogenic cal i were successful y in-duced from al the combinations. The efficiency of embryogenic cal us induction, embryogenesis, and plantlet regeneration were significantly different among the 12 combinations. The result showed that the embryogenesis ratio was the highest in BK3 combination (0.50 mg/L IBA and 0.50 mg/L KT), 72.86% of embryogenic cal i differentiated into somatic embryos after being cultured on CIM for 80 d, and 80.93% of the somatic embryos final y regenerated into plants on SEM (somatic em-bryo induction medium). [Conclusion] These results indicate that hormone combina-tion BK3 (0.50 mg/LIBA and 0.50 mg/L KT) was the best medium for somatic em-bryogenesis and plant regeneration from Xinluzao33.

  7. Early markers are present in both embryogenesis pathways from microspores and immature zygotic embryos in cork oak, Quercus suber L

    OpenAIRE

    2014-01-01

    Background: In Quercus suber, cork oak, a Mediterranean forest tree of economic and social interest, rapid production of isogenic lines and clonal propagation of elite genotypes have been achieved by developing in vitro embryogenesis from microspores and zygotic embryos respectively. Despite its high potential in tree breeding strategies, due to their recalcitrancy, the efficiency of embryogenesis in vitro systems in many woody species is still very low since factors responsible for embryogen...

  8. Foregut duplication cysts:A report of two cases with emphasis on embryogenesis

    Institute of Scientific and Technical Information of China (English)

    Thaer Khoury; Louis Rivera

    2011-01-01

    Duplication cyst of the stomach with a pseudostratified columnar ciliated epithelium is extremely rare.We describe two cases of these cysts,with emphasis on their immunophenotype and embryogenesis.The first patient was a 29-year-old man who presented with cramping abdominal pain in his left lower quadrant.The second patient was a 26-year-old woman who had a history,over several years,of chronic epigastric abdominal pain radiating to her back.Both lesions were surgically removed.They showed the same histomorphology.The cysts were lined by a pseudostratified respiratory epithelium with ciliated cells.The first cyst was connected to the stomach,while the second cyst was not connected.Both cysts expressed thyroid transcription factor-1 (TTF-1)and surfactant.In this report,we explore the possible embryogenesis of these lesions in the light of TTF-1 and surfactant expression.

  9. Study of elemental variations during somatic embryogenesis in sugarcane using photon induced X-ray probe

    Science.gov (United States)

    Desai, N. S.; Joseph, D.; Suprasanna, P.; Bapat, V. A.

    2006-11-01

    Energy-dispersive X-ray fluorescence technique (EDXRF) has been extensively used to characterize trace element profiles during plant growth under stress and development. In this study, elemental accumulation was analyzed using EDXRF technique during somatic embryogenesis, from de-differentiated callus (S1) to proembryogenic callus (S2), embryogenic callus with developing embryos (S3) and embryo converted plantlets (S4, S5). There was much variation in Mg, K, Ca, Mn, Fe, Cu and Zn. Higher Mg (4.6%) K (1068 ppm) and Fe accumulation was observed in proembryogenic callus (S2) stage compared to other stages suggesting specific elemental accumulation in embryogenic callus. The results suggest that the information on the accumulation of elements during developmental stages in vitro could be useful for formulating a media for induction of high frequency of embryogenesis in sugarcane.

  10. The effect of epigenetic sperm abnormalities on early embryo-genesis

    Institute of Scientific and Technical Information of China (English)

    Benjamin R. Emery; Douglas T. Carrell

    2006-01-01

    Sperm are a highly specialized cell type derived to deliver the paternal haploid genome to the oocyte. The epigenetic,or gene regulatory, properties and mechanisms of the sperm assist in preparation of the paternal genome to contribute to embryogenesis and the genome of the zygote. Many recent studies have addressed the issue of altered epigenetic processes in the sperm. This review evaluates the current understanding of DNA damage, chromosome aneuploidy,reduced telomere length, malformations of the centrosome, genomic imprinting errors, altered mRNA profiles, and abnormal nuclear packaging in the sperm prior to fertilization and the observed effects on embryogenesis. Attention has also been given to understanding the underlying etiology of sperm with altered epigenetic mechanisms in humans.

  11. Plant Regeneration of Sweet Potato via Somatic Embryogenesis from Different Explants

    Institute of Scientific and Technical Information of China (English)

    Ling ZHANG; Hongxuan XU; Baifu QIN; Zhihua LIA0; Min CHEN; Chunxian YANG; Yufan FU; Qitang ZHANG

    2012-01-01

    [Objective] This study aimed to regenerate plants of sweet potato (Ipomoea batatas) cultivar Xushu22 via somatic embryogenesis, using leaf and shoot apex as explants. [Method] The leaf and shoot apex of Xushu 22 were separately cultured on MSB medium and MSD medium. The induced embryogenic calluses were then cultured on MS medium. The regeneration frequency of leaf and shoot apex ex- plants were respectively calculated. [Result] The average frequency of leaf explants developing somatic callus was 95.69% compared to 30.56% in case of shoot apex explants. There were different types of morphogenic structures in the process of so- matic embryo development. Leaf explants gave a high regeneration frequency to 60.61%, while the regeneration frequency of shoot apices was 22%. In addition, no morphological variations were observed in the regeneration plants. [Conclusion] Leaf explant was better than shoot apices in plant regeneration of Xushu22 via somatic embryogenesis.

  12. Gene-nutrient interactions: importance of folic acid and vitamin B12 during early embryogenesis.

    Science.gov (United States)

    Finnell, Richard H; Shaw, Gary M; Lammer, Edward J; Rosenquist, Thomas H

    2008-06-01

    The role that nutritional factors play in mammalian development has received renewed attention over the past two decades as the scientific literature has exploded with reports that folic acid supplementation in the periconceptional period can protect embryos from a number of highly significant malformations. As is often the case, the relationship between B vitamin supplementation and improved pregnancy outcomes is more complicated than initially perceived, as the interaction between nutritional factors and selected genes must be considered. In this review, we attempt to summarize the complex clinical and experimental literature on nutritional factors, their biological transport mechanisms, and interactions with genetic polymorphisms that impact early embryogenesis. While not exhaustive, our goal was to provide an overview of important gene-nutrient interactions, focusing on folic acid and vitamin B12, to serve as a framework for understanding the multiple roles they play in early embryogenesis.

  13. Effect of plant growth regulators on somatic embryogenesis in leaf cultures of Coffea canephora.

    Science.gov (United States)

    Hatanaka, T; Arakawa, O; Yasuda, T; Uchida, N; Yamaguchi, T

    1991-07-01

    The effects of plant growth regulators on somatic embryogenesis were studied in leaf cultures of Coffea canephora. The maximum number of somatic embryos were obtained on media that contained only cytokinin as a plant growth regulator. All of the auxins tested (NAA, IBA, IAA and 2, 4-D) inhibited the formation of embryos. The optimal concentration of each cytokinin (2-iP, BA and kinetin) for somatic embryogenesis was 5 μM. Under optimal conditions, each explant formed more than 100 embryoids with little callus and few adventitious roots. Embryoids were formed only at the cut edges of the leaf discs. Cytokinins were absorbed only at the cut edges of leaf discs that were in contact with the medium, and were not transported to other parts of the explant.

  14. [Somatic embryogenesis and plant regeneration in vitro from young shoots of Aralia elate (Miq.) Seem].

    Science.gov (United States)

    Li, J M; Li, X W; Zhang, D Y; Xing, M

    2001-06-01

    Explants excised from the young shoots of Aralia elata (Miq.) Seem. were cultured on MS media. Calli were induced from the explants on MS medium supplemented with 0.5 mg/L 2, 4-D, 0.5 mg/L BA and 0.5 mg/L NAA. Then these calli were transferred onto the MS medium containing 2.0 mg/L 2,4-D + 0.5 mg/L BA + 0.5 mg/L NAA and 0.2% activated charcoal. Under these conditions the somatic embryoids were observed and regenerated plants were obtained from somatic embryogenesis. Then, a experimental system with stability and high regenerating efficiency has been set up for the propagation of the young plants, the cell breeding technology and the control of somatic embryogenesis of Aralia elata (Miq.).

  15. Somatic embryogenesis and plantlet regeneration in the genus Secale : 1. Somatic embryogenesis and organogenesis from cultured immature embryos of five wild species of rye.

    Science.gov (United States)

    Rybczyński, J J; Zduńczyk, W

    1986-12-01

    A tissue culture of five wild species of the Secale genus, i.e., S. africanum (Stapf.), S. ancestrale (Zhuk.), S. kuprianovii (Grossh), S. segetale (Rosher.), and S. vavilovii (Grossh), from immature embryos of sizes (stages) varying between 1.0 mm to 3.0mm, cultured on MS (1962) mineral nutrient medium supplemented with 0.62 mg/1-5.0 mg/1 of 2,4-D, was established. Initially various types of callus were observed and a correlation between genotype, size of explant and 2,4-D concentration was found. The best embryogenic response was observed when explants were smaller than 1.0 mm. Induction of somatic embryogenesis of 2.0 mm-3.0 mm explants required a higher concentration of 2,4-D. Most embryoids were formed in the presence of 5.0 mg/l of 2,4-D. Secale africanum and S. kuprianovii appeared to have the highest embryogenic capacity among the five investigated species. For embryoids germination to plantlets the MS medium supplemented with GA3 and cytokinins was used. Ultimately, out of the 932 regenerants obtained 364 originated from somatic embryogenesis.

  16. Somatic embryogenesis in immature cotyledons of Manchurian ash (Fraxinus mandshurica Rupr.)

    Science.gov (United States)

    Somatic embryogenesis was obtained from immature cotyledon explants that were cultured on half-strength Murashige and Skoog (MS) salts and vitamins with 5.4 uM naphthaleneacetic acid (NAA) and 0.2 uM thidiazuron (TDZ) plus a 4x4 factorial combination of 0,9.8, 34.6, or 49.2 uM indole-3-butyric acid ...

  17. Enhanced somatic embryogenesis in Theobroma cacao using the homologous BABY BOOM transcription factor.

    Science.gov (United States)

    Florez, Sergio L; Erwin, Rachel L; Maximova, Siela N; Guiltinan, Mark J; Curtis, Wayne R

    2015-05-16

    Theobroma cacao, the chocolate tree, is an important economic crop in East Africa, South East Asia, and South and Central America. Propagation of elite varieties has been achieved through somatic embryogenesis (SE) but low efficiencies and genotype dependence still presents a significant limitation for its propagation at commercial scales. Manipulation of transcription factors has been used to enhance the formation of SEs in several other plant species. This work describes the use of the transcription factor Baby Boom (BBM) to promote the transition of somatic cacao cells from the vegetative to embryonic state. An ortholog of the Arabidopsis thaliana BBM gene (AtBBM) was characterized in T. cacao (TcBBM). TcBBM expression was observed throughout embryo development and was expressed at higher levels during SE as compared to zygotic embryogenesis (ZE). TcBBM overexpression in A. thaliana and T. cacao led to phenotypes associated with SE that did not require exogenous hormones. While transient ectopic expression of TcBBM provided only moderate enhancements in embryogenic potential, constitutive overexpression dramatically increased SE proliferation but also appeared to inhibit subsequent development. Our work provides validation that TcBBM is an ortholog to AtBBM and has a specific role in both somatic and zygotic embryogenesis. Furthermore, our studies revealed that TcBBM transcript levels could serve as a biomarker for embryogenesis in cacao tissue. Results from transient expression of TcBBM provide confirmation that transcription factors can be used to enhance SE without compromising plant development and avoiding GMO plant production. This strategy could compliment a hormone-based method of reprogramming somatic cells and lead to more precise manipulation of SE at the regulatory level of transcription factors. The technology would benefit the propagation of elite varieties with low regeneration potential as well as the production of transgenic plants, which

  18. Phosphoenolpyruvate carboxykinase in bovine tick Rhipicephalus (Boophilus) micro plus embryogenesis and starvation larvae

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, J.G. de; Mentizingen, L.G.; Logullo, C. [Universidade Estadual do Norte Fluminense Darcy Ribeiro (UENF), Campos dos Goytacazes, RJ (Brazil). Centro de Biociencias e Biotecnologia. Lab.de Quimica e Funcao de Proteinas e Peptideos (LQFPP); Andrade, C.P. de; Vaz Junior, Itabajara [Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS (Brazil). Centro de Biotecnologia; Daffre, S.; Esteves, E. [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Ciencias Biomedicas

    2008-07-01

    Full text: Phosphoenolpyruvate carboxykinase (PEPCK) is considered a key rate controlling enzyme in gluconeogenesis pathway. Gluconeogenesis is a highly regulated process, catalyzed by several enzymes subject to regulation by insulin. Normally, insulin rapidly and substantially inhibits PEPCK gene transcription and the PEPCK activity is proportional to the rate of gene transcription. The transcriptional regulation of the PEPCK gene has been extensively studied. CREM is the transcription factor that bind efficiently to the putative cyclic AMP response element (CRE) in PEPCK gene. Several other transcription factors can bind to this element and activate transcription. In oviparous animals, such as bovine tick R. microplus, the embryonic development occurs outside the maternal organism, implying that all the nutrients necessary for embryogenesis must be present in the oocytes. We observed the relationship between the main energy sources and the morphogenetic changes that occur during R. microplus tick embryogenesis. Energy homeostasis is maintained by glycogen mobilization in the beginning of embryogenesis, as its content is drastically decreased during the first five days of development. Afterwards, the activity of the gluconeogenesis enzyme PEPCK increases enormously, as indicated by a concomitant increase in glucose content (Moraes et al., 2007). Here, we analyzed PEPCK gene transcription by qPCR during the embryogenesis and starvation larvae. The PEPCK transcription was higher at first and 15th day eggs of the development. In larvae the levels of PEPCK transcripts is increased at fifth day after hatch. However, the activity is continuous increased in larvae the form first up to 15th day. Now we are investigating the involvement of CREM in the PEPCK gene transcription in these cells. In this sense, we obtained CREM sequence from TIGR ESTs R. microplus bank and designed the specific primers to qPCR. Taken together our results suggest the involvement of PEPCK to the

  19. Involvement of peroxidase activity in developing somatic embryos of Medicago arborea L. Identification of an isozyme peroxidase as biochemical marker of somatic embryogenesis.

    Science.gov (United States)

    Gallego, Piedad; Martin, Luisa; Blazquez, Antonio; Guerra, Hilario; Villalobos, Nieves

    2014-01-15

    The legume Medicago arborea L. is very interesting as regards the regeneration of marginal arid soils. The problem is that it does not have a good germinative yield. It was therefore decided to regenerate via somatic embryogenesis and find a marker of embryogenic potential. In this study, peroxidase activity was evaluated in non-embryogenic and embryogenic calli from M. arborea L. A decrease in soluble peroxidase activity is observed in its embryonic calli at the time at which the somatic embryos begin to appear. This activity is always lower in embryonic calli than in non-embryonic ones (unlike what happens in the case of wall-bound peroxidases). These results suggest that peroxidases can be considered to be enzymes involved in somatic embryogenesis in M. arborea. In addition, isozyme analyses were carried out on protein extracts using polyacrylamide gel electrophoresis. The band called P5 was detected only in embryogenic cultures at very early stages of development. This band was digested with trypsin and analyzed using linear ion trap (LTQ) mass spectrometer. In P5 isoform a peroxidase-L-ascorbate peroxidase was identified. It can be used as a marker that allows the identification of embryological potential.

  20. Screen for stage-specific expression genes between tail bud stage and heartbeat beginning stage in embryogenesis of gynogenetic silver crucian carp

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A systemic study was initiated to identify stage-specific expression genes in fish embryogenesis by using suppression subtractive hybridization (SSH) technique. In this study, we presented a preliminary result on screen for stage-specific expression genes between tail bud stage (TBS) and heartbeat beginning stage (HBS) in gynogenetic silver crucian carp (Carassius auratus gibelio). Two SSH plasmid libraries specific for TBS embryos and HBS embryos were constructed, and stage-specific expression genes were screened between the two stages. 1963 TBS positive clones and 2466 HBS positive clones were sampled to PCR amplification, and 1373 TBS and 1809 HBS PCR positive clones were selected to carry out dot blots. 169TBS dot blot positive clones and 272 HBS dot blot positive clones were sequenced. Searching GenBank by using these nucleotide sequences indicated that most of the TBS dot blot positive clones could not be found homologous sequences in the database, while known genes were mainly detected from HBS dot blot positive clones. Of the 79 known genes, 20 were enzymes or kinases involved in important metabolism of embryonic development. Moreover, specific expressions of partial genes were further confirmed by virtual northern blots. This study is the first step for making a large attempt to study temporal and spatial control f gene expression in the gynogenetic fish embryogenesis.

  1. Comparative Developmental Staging of Female and Male Water Fleas Daphnia pulex and Daphnia magna During Embryogenesis.

    Science.gov (United States)

    Toyota, Kenji; Hiruta, Chizue; Ogino, Yukiko; Miyagawa, Shinichi; Okamura, Tetsuro; Onishi, Yuta; Tatarazako, Norihisa; Iguchi, Taisen

    2016-02-01

    The freshwater crustacean genus Daphnia has been used extensively in ecological, developmental and ecotoxicological studies. Daphnids produce only female offspring by parthenogenesis under favorable conditions, but in response to various unfavorable conditions and external stimuli, they produce male offspring. Although we reported that exogenous exposure to juvenile hormones and their analogs can induce male offspring even under female-producing conditions, we recently established a male induction system in the Daphnia pulex WTN6 strain simply by changing day-length. This male and female induction system is suitable for understanding the innate mechanisms of sexual dimorphic development in daphnids. Embryogenesis has been described as a normal plate (developmental staging) in various daphnid species; however, all studies have mainly focused on female development. Here, we describe the developmental staging of both sexes during embryogenesis in two representative daphnids, D. pulex and D. magna, based on microscopic time-course observations. Our findings provide the first detailed insights into male embryogenesis in both species, and contribute to the elucidation of the mechanisms underlying sexual differentiation in daphnids.

  2. Functional analysis of Bombyx Wnt1 during embryogenesis using the CRISPR/Cas9 system.

    Science.gov (United States)

    Zhang, Zhongjie; Aslam, Abu F M; Liu, Xiaojing; Li, Muwang; Huang, Yongping; Tan, Anjiang

    2015-08-01

    Recently established, custom-designed nuclease technologies such as the clustered regularly interspaced short palindromic repeat (CRISPR)-associated system provide attractive genome editing tools. Targeted gene mutagenesis using the CRISPR/Cas9 system has been achieved in several orders of insects. However, outside of studies on Drosophila melanogaster and the lepidopteron model insect Bombyx mori, little success has been reported, which is largely due to a lack of effective genetic manipulation tools that can be used in other insect orders. To create a simple and effective method of gene knockout analysis, especially for dissecting gene functioning during insect embryogenesis, we performed a functional analysis of the Bombyx Wnt1 (BmWnt1) gene using Cas9/sgRNA-mediated gene mutagenesis. The Wnt1 gene is required for embryonic patterning in various organisms, and its crucial roles during embryogenesis have been demonstrated in several insect orders. Direct injection of Cas9 mRNA and BmWnt1-specific sgRNA into Bombyx embryos induced a typical Wnt-deficient phenotype: injected embryos could not hatch and exhibited severe defects in body segmentation and pigmentation in a dose-dependent manner. Quantitative real-time PCR (qRT-PCR) analysis revealed that Hox genes were down-regulated after BmWnt1 depletion. Furthermore, large deletion, up to 18Kb, ware generated. The current study demonstrates that using the CRISPR/Cas9 system is a promising approach to achieve targeted gene mutagenesis during insect embryogenesis.

  3. Genes of both parental origins are differentially involved in early embryogenesis of a tobacco interspecies hybrid.

    Directory of Open Access Journals (Sweden)

    Jun-E Zhang

    Full Text Available BACKGROUND: In animals, early embryonic development is largely dependent on maternal transcripts synthesized during gametogenesis. However, in higher plants, the extent of maternal control over zygote development and early embryogenesis is not fully understood yet. Nothing is known about the activity of the parental genomes during seed formation of interspecies hybrids. METHODOLOGY/PRINCIPAL FINDINGS: Here, we report that an interspecies hybridization system between SR1 (Nicotiana tabacum and Hamayan (N. rustica has been successfully established. Based on the system we selected 58 genes that have polymorphic sites between SR1 and Hamayan, and analyzed the allele-specific expression of 28 genes in their hybrid zygotes (Hamayan x SR1. Finally the allele-specific expressions of 8 genes in hybrid zygotes were repeatedly confirmed. Among them, 4 genes were of paternal origin, 1 gene was of maternal origin and 3 genes were of biparental origin. These results revealed obvious biparental involvement and differentially contribution of parental-origin genes to zygote development in the interspecies hybrid. We further detected the expression pattern of the genes at 8-celled embryo stage found that the involvement of the parental-origin genes may change at different stages of embryogenesis. CONCLUSIONS/SIGNIFICANCE: We reveal that genes of both parental origins are differentially involved in early embryogenesis of a tobacco interspecies hybrid and functions in a developmental stage-dependent manner. This finding may open a window to seek for the possible molecular mechanism of hybrid vigor.

  4. Effects of p-chlorophenoxyisobutyric acid, arabinogalactan, and activated charcoal on microspore embryogenesis in kale.

    Science.gov (United States)

    Niu, R Q; Zhang, Y; Tong, Y; Liu, Z Y; Wang, Y H; Feng, H

    2015-04-27

    To improve embryogenesis in microspore cultures of kale (Brassica oleracea L. var. acephala DC.), 6-benzylaminopurine (6-BA), naphthaleneacetic acid (NAA), arabinogalactan (AG), p-chlorophenoxyisobutyric acid (PCIB), and activated charcoal (AC) were added to the medium using four varieties of kale. The results showed that the addition of AG (0.1-0.2 g/L), AC (0.1-0.2 g/L) or a combination of 6-BA (0.1-0.2 mg/L) and NAA (0.1-0.2 mg/L) promoted embryo-genesis. Adding 40 μM PCIB or a combination of 40 μM PCIB and 0.2 g/L AC to NLN-13 medium at pH 5.8 effectively enhanced embryogenesis. Treatment with a combination of 40 μM PCIB and 10 mg/L AG gave the highest rate of embryonic induction, especially in genotype "Y007," which showed a twelve-fold increase in yield.

  5. Annual Reproductive Cycle and Unusual Embryogenesis of a Temperate Coral in the Mediterranean Sea.

    Directory of Open Access Journals (Sweden)

    Chiara Marchini

    Full Text Available The variety of reproductive processes and modes among coral species reflects their extraordinary regeneration ability. Scleractinians are an established example of clonal animals that can exhibit a mixed strategy of sexual and asexual reproduction to maintain their populations. This study provides the first description of the annual reproductive cycle and embryogenesis of the temperate species Caryophyllia inornata. Cytometric analyses were used to define the annual development of germ cells and embryogenesis. The species was gonochoric with three times more male polyps than female. Polyps were sexually mature from 6 to 8 mm length. Not only females, but also sexually inactive individuals (without germ cells and males were found to brood their embryos. Spermaries required 12 months to reach maturity, while oogenesis seemed to occur more rapidly (5-6 months. Female polyps were found only during spring and summer. Furthermore, the rate of gamete development in both females and males increased significantly from March to May and fertilization was estimated to occur from April to July, when mature germ cells disappeared. Gametogenesis showed a strong seasonal influence, while embryos were found throughout the year in males and in sexually inactive individuals without a defined trend. This unusual embryogenesis suggests the possibility of agamic reproduction, which combined with sexual reproduction results in high fertility. This mechanism is uncommon and only four other scleractinians (Pocillopora damicornis, Tubastraea diaphana, T. coccinea and Oulastrea crispata have been shown to generate their broods asexually. The precise nature of this process is still unknown.

  6. In Vitro Callus Induction and Embryogenesis of Oil Palm (Elaeis guineensis Jacq. from Leaf Explants

    Directory of Open Access Journals (Sweden)

    DWI HAPSORO

    2011-06-01

    Full Text Available This research was to study in vitro callus induction and somatic embryogenesis in oil palm from leaf explants. Young leaf segments from mature oil palm were cultured on MS medium supplemented with different concentrations of 2,4-D with or without addition of 2 g/l activated charcoal (AC or 2,4-D and picloram. Embryogenesis induction was done using MS medium containing 2,4-D 450 M and benziladenine 4.4 M with 3g/l activated charcoal. The treatment of 2,4-D 15 M resulted in the highest percentage of callus induction. The treatment of 2,4-D and AC showed that 2,4-D 450 M and AC led to higher percentage of callus induction than that of 2,4-D 400 M and 2 g/l AC. Embryogenesis occured in 27 out of 250 clumps of primary callus was occurred after 2-3 times subcultures. Somatic embryo development occurred when the embryogenic callus was transferred on the same basal medium supplemented with casein hydrolysate with 1 M BA or growth regulator free basal medium with 2 g/l activated charcoal.

  7. The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

    Science.gov (United States)

    Aygün, Ali; Narinç, Doǧan

    2016-04-01

    Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (Ptibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

  8. The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

    Energy Technology Data Exchange (ETDEWEB)

    Aygün, Ali, E-mail: aaygun@selcuk.edu.tr [Selcuk University, Faculty of Agriculture, Department of Animal Science, Konya, 42075 (Turkey); Narinç, Doğan, E-mail: narincd@gmail.com [Namik Kemal University, Faculty of Veterinary Medicine, Department of Genetics, Tekirdag, 59100 (Turkey)

    2016-04-18

    Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

  9. Late Accretion and the Late Veneer

    CERN Document Server

    Morbidelli, Alessandro

    2014-01-01

    The concept of Late Veneer has been introduced by the geochemical community to explain the abundance of highly siderophile elements in the Earth's mantle and their chondritic proportions relative to each other. However, in the complex scenario of Earth accretion, involving both planetesimal bombardment and giant impacts from chondritic and differentiated projectiles, it is not obvious what the "Late Veneer" actually corresponds to. In fact, the process of differentiation of the Earth was probably intermittent and there was presumably no well-defined transition between an earlier phase where all metal sunk into the core and a later phase in which the core was a closed entity separated from the mantle. In addition, the modellers of Earth accretion have introduced the concept of "Late Accretion", which refers to the material accreted by our planet after the Moon-forming event. Characterising Late Veneer, Late Accretion and the relationship between the two is the major goal of this chapter.

  10. The significance of PIWI family expression in human lung embryogenesis and non-small cell lung cancer.

    Science.gov (United States)

    Navarro, Alfons; Tejero, Rut; Viñolas, Nuria; Cordeiro, Anna; Marrades, Ramon M; Fuster, Dolors; Caritg, Oriol; Moises, Jorge; Muñoz, Carmen; Molins, Laureano; Ramirez, Josep; Monzo, Mariano

    2015-10-13

    The expression of Piwi-interacting RNAs, small RNAs that bind to PIWI proteins, was until recently believed to be limited to germinal stem cells. We have studied the expression of PIWI genes during human lung embryogenesis and in paired tumor and normal tissue prospectively collected from 71 resected non-small-cell lung cancer patients. The mRNA expression analysis showed that PIWIL1 was highly expressed in 7-week embryos and downregulated during the subsequent weeks of development. PIWIL1 was expressed in 11 of the tumor samples but in none of the normal tissue samples. These results were validated by immunohistochemistry, showing faint cytoplasmic reactivity in the PIWIL1-positive samples. Interestingly, the patients expressing PIWIL1 had a shorter time to relapse (TTR) (p = 0.006) and overall survival (OS) (p = 0.0076) than those without PIWIL1 expression. PIWIL2 and 4 were downregulated in tumor tissue in comparison to the normal tissue (p < 0.001) and the patients with lower levels of PIWIL4 had shorter TTR (p = 0.048) and OS (p = 0.033). In the multivariate analysis, PIWIL1 expression emerged as an independent prognostic marker. Using 5-Aza-dC treatment and bisulfite sequencing, we observed that PIWIL1 expression could be regulated in part by methylation. Finally, an in silico study identified a stem-cell expression signature associated with PIWIL1 expression.

  11. Identification of a PTC-containing DlRan transcript and its differential expression during somatic embryogenesis in Dimocarpus longan.

    Science.gov (United States)

    Fang, Zhi-Zhen; Lai, Cheng-Chun; Zhang, Ya-Ling; Lin, Yu-Ling; Lai, Zhong-Xiong

    2013-10-15

    RAN (Ras-related nuclear protein) plays crucial roles in multiple cellular processes in yeast, animals and plants. Here we present a DlRan gene and its alternative splicing transcripts containing premature terminator codons (PTCs), identified from embryogenic cultures in longan. Multiple alignment and splicing pattern analyses indicated that DlRan-1 transcript harboring PTC was the consequence of alternative splicing. The accumulation of DlRan PTC-containing transcripts increased significantly when the embryogenic calli were treated with the translation inhibitor, cycloheximide, indicating that DlRan-1 may be targeted by NMD. The analysis of expression profiles of DlRan transcripts revealed that differential expression levels of the alternative spliced DlRan transcripts occurred during the development of embryogenic callus, globular-shaped embryos, and cotyledon-shaped embryos, respectively, in the longan somatic embryogenesis, and were in consistent with the embryo development in corresponding wild-type transcripts. The present work offers evidence to speculate that the alternatively spliced PTC-containing transcripts can be functional and may shed light on expression regulation of DlRan during development of the longan somatic embryos. © 2013 Elsevier B.V. All rights reserved.

  12. Auxin Biosynthesis, Accumulation, Action and Transport are Involved in Stress-Induced Microspore Embryogenesis Initiation and Progression in Brassica napus.

    Science.gov (United States)

    Rodríguez-Sanz, Héctor; Solís, María-Teresa; López, María-Fernanda; Gómez-Cadenas, Aurelio; Risueño, María C; Testillano, Pilar S

    2015-07-01

    Isolated microspores are reprogrammed in vitro by stress, becoming totipotent cells and producing embryos and plants via a process known as microspore embryogenesis. Despite the abundance of data on auxin involvement in plant development and embryogenesis, no data are available regarding the dynamics of auxin concentration, cellular localization and the expression of biosynthesis genes during microspore embryogenesis. This work involved the analysis of auxin concentration and cellular accumulation; expression of TAA1 and NIT2 encoding enzymes of two auxin biosynthetic pathways; expression of the PIN1-like efflux carrier; and the effects of inhibition of auxin transport and action by N-1-naphthylphthalamic acid (NPA) and α-(p-chlorophenoxy) isobutyric acid (PCIB) during Brassica napus microspore embryogenesis. The results indicated de novo auxin synthesis after stress-induced microspore reprogramming and embryogenesis initiation, accompanying the first cell divisions. The progressive increase of auxin concentration during progression of embryogenesis correlated with the expression patterns of TAA1 and NIT2 genes of auxin biosynthetic pathways. Auxin was evenly distributed in early embryos, whereas in heart/torpedo embryos auxin was accumulated in apical and basal embryo regions. Auxin efflux carrier PIN1-like gene expression was induced in early multicellular embryos and increased at the globular/torpedo embryo stages. Inhibition of polar auxin transport (PAT) and action, by NPA and PCIB, impaired embryo development, indicating that PAT and auxin action are required for microspore embryo progression. NPA also modified auxin embryo accumulation patterns. These findings indicate that endogenous auxin biosynthesis, action and polar transport are required in stress-induced microspore reprogramming, embryogenesis initiation and progression.

  13. Are we ready to predict late effects?

    DEFF Research Database (Denmark)

    Salz, Talya; Baxi, Shrujal S; Raghunathan, Nirupa;

    2015-01-01

    BACKGROUND: After completing treatment for cancer, survivors may experience late effects: consequences of treatment that persist or arise after a latent period. PURPOSE: To identify and describe all models that predict the risk of late effects and could be used in clinical practice. DATA SOURCES:...

  14. Vasoactive intestinal peptide antagonist treatment during mouse embryogenesis impairs social behavior and cognitive function of adult male offspring.

    Science.gov (United States)

    Hill, Joanna M; Cuasay, Katrina; Abebe, Daniel T

    2007-07-01

    Vasoactive intestinal peptide (VIP) is a regulator of rodent embryogenesis during the period of neural tube closure. VIP enhanced growth in whole cultured mouse embryos; treatment with a VIP antagonist during embryogenesis inhibited growth and development. VIP antagonist treatment during embryogenesis also had permanent effects on adult brain chemistry and impaired social recognition behavior in adult male mice. The neurological deficits of autism appear to be initiated during neural tube closure and social behavior deficits are among the key characteristics of this disorder that is more common in males and is frequently accompanied by mental retardation. The current study examined the blockage of VIP during embryogenesis as a model for the behavioral deficits of autism. Treatment of pregnant mice with a VIP antagonist during embryonic days 8 through 10 had no apparent effect on the general health or sensory or motor capabilities of adult offspring. However, male offspring exhibited reduced sociability in the social approach task and deficits in cognitive function, as assessed through cued and contextual fear conditioning. Female offspring did not show these deficiencies. These results suggest that this paradigm has usefulness as a mouse model for aspects of autism as it selectively impairs male offspring who exhibit the reduced social behavior and cognitive dysfunction seen in autism. Furthermore, the study indicates that the foundations of some aspects of social behavior are laid down early in mouse embryogenesis, are regulated in a sex specific manner and that interference with embryonic regulators such as VIP can have permanent effects on adult social behavior.

  15. The BABY BOOM Transcription Factor Activates the LEC1-ABI3-FUS3-LEC2 Network to Induce Somatic Embryogenesis.

    Science.gov (United States)

    Horstman, Anneke; Li, Mengfan; Heidmann, Iris; Weemen, Mieke; Chen, Baojian; Muino, Jose M; Angenent, Gerco C; Boutilier, Kim

    2017-10-01

    Somatic embryogenesis is an example of induced cellular totipotency, where embryos develop from vegetative cells rather than from gamete fusion. Somatic embryogenesis can be induced in vitro by exposing explants to growth regulators and/or stress treatments. The BABY BOOM (BBM) and LEAFY COTYLEDON1 (LEC1) and LEC2 transcription factors are key regulators of plant cell totipotency, as ectopic overexpression of either transcription factor induces somatic embryo formation from Arabidopsis (Arabidopsis thaliana) seedlings without exogenous growth regulators or stress treatments. Although LEC and BBM proteins regulate the same developmental process, it is not known whether they function in the same molecular pathway. We show that BBM transcriptionally regulates LEC1 and LEC2, as well as the two other LAFL genes, FUSCA3 (FUS3) and ABSCISIC ACIDINSENSITIVE3 (ABI3). LEC2 and ABI3 quantitatively regulate BBM-mediated somatic embryogenesis, while FUS3 and LEC1 are essential for this process. BBM-mediated somatic embryogenesis is dose and context dependent, and the context-dependent phenotypes are associated with differential LAFL expression. We also uncover functional redundancy for somatic embryogenesis among other Arabidopsis BBM-like proteins and show that one of these proteins, PLETHORA2, also regulates LAFL gene expression. Our data place BBM upstream of other major regulators of plant embryo identity and totipotency. © 2017 American Society of Plant Biologists. All Rights Reserved.

  16. The genomic distribution and function of histone variant HTZ-1 during C. elegans embryogenesis.

    Directory of Open Access Journals (Sweden)

    Christina M Whittle

    Full Text Available In all eukaryotes, histone variants are incorporated into a subset of nucleosomes to create functionally specialized regions of chromatin. One such variant, H2A.Z, replaces histone H2A and is required for development and viability in all animals tested to date. However, the function of H2A.Z in development remains unclear. Here, we use ChIP-chip, genetic mutation, RNAi, and immunofluorescence microscopy to interrogate the function of H2A.Z (HTZ-1 during embryogenesis in Caenorhabditis elegans, a key model of metazoan development. We find that HTZ-1 is expressed in every cell of the developing embryo and is essential for normal development. The sites of HTZ-1 incorporation during embryogenesis reveal a genome wrought by developmental processes. HTZ-1 is incorporated upstream of 23% of C. elegans genes. While these genes tend to be required for development and occupied by RNA polymerase II, HTZ-1 incorporation does not specify a stereotypic transcription program. The data also provide evidence for unexpectedly widespread independent regulation of genes within operons during development; in 37% of operons, HTZ-1 is incorporated upstream of internally encoded genes. Fewer sites of HTZ-1 incorporation occur on the X chromosome relative to autosomes, which our data suggest is due to a paucity of developmentally important genes on X, rather than a direct function for HTZ-1 in dosage compensation. Our experiments indicate that HTZ-1 functions in establishing or maintaining an essential chromatin state at promoters regulated dynamically during C. elegans embryogenesis.

  17. Cell wall glucomannan in Arabidopsis is synthesised by CSLA glycosyltransferases, and influences the progression of embryogenesis.

    Science.gov (United States)

    Goubet, Florence; Barton, Christopher J; Mortimer, Jennifer C; Yu, Xiaolan; Zhang, Zhinong; Miles, Godfrey P; Richens, Jenny; Liepman, Aaron H; Seffen, Keith; Dupree, Paul

    2009-11-01

    Mannans are hemicellulosic polysaccharides that have previously been implicated as structural constituents of cell walls and as storage reserves but which may serve other functions during plant growth and development. Several members of the Arabidopsis cellulose synthase-like A (CSLA) family have previously been shown to synthesise mannan polysaccharides in vitro when heterologously expressed. It has also been found that CSLA7 is essential for embryogenesis, suggesting a role for the CSLA7 product in development. To determine whether the CSLA proteins are responsible for glucomannan synthesis in vivo, we characterised insertion mutants in each of the nine Arabidopsis CSLA genes and several double and triple mutant combinations. csla9 mutants showed substantially reduced glucomannan, and triple csla2csla3csla9 mutants lacked detectable glucomannan in stems. Nevertheless, these mutants showed no alteration in stem development or strength. Overexpression of CSLA2, CSLA7 and CSLA9 increased the glucomannan content in stems. Increased glucomannan synthesis also caused defective embryogenesis, leading to delayed development and occasional embryo death. The embryo lethality of csla7 was complemented by overexpression of CSLA9, suggesting that the glucomannan products are similar. We conclude that CSLA2, CSLA3 and CSLA9 are responsible for the synthesis of all detectable glucomannan in Arabidopsis stems, and that CSLA7 synthesises glucomannan in embryos. These results are inconsistent with a substantial role for glucomannan in wall strength in Arabidopsis stems, but indicate that glucomannan levels affect embryogenesis. Together with earlier heterologous expression studies, the glucomannan deficiency observed in csla mutant plants demonstrates that the CSLA family encodes glucomannan synthases.

  18. Towards industrial production of tree varieties through somatic embryogenesis and other vegetative propagation technologies

    DEFF Research Database (Denmark)

    Find, Jens Iver

    2016-01-01

    untested cell lines. The developed method ensured a very good selection of genotypes at any of the involved steps: initiation, proliferation, cryo preservation, maturation, germination, and nursery culture. Growth and development of clonally propagated plants in the field were similar to those of seed......The main focus of the research on somatic embryogenesis in nordmanns fir has until recently been on improving the basic protocols in each step of the process. However, with recent developments, one single set of methods has shown to be effective for production of plants from more than 500 different...

  19. Somatic embryogenesis and regeneration of plants in the bamboo Dendrocalamus strictus.

    Science.gov (United States)

    Rao, I U; Ramanuja Rao, I V; Narang, V

    1985-08-01

    Somatic embryogenesis leading to plant regeneration has been achieved in the bamboo, Dendrocalamus strictus, by culturing seeds (caryopses) on B5 basal medium supplemented with 2,4-dichlorophenoxyacetic acid. Callus cultures obtained from the embryonal end of the seeds differentiated chlorophyllous embryoids. On transfer to a germination medium (B5 liquid, sucrose, indolebutyric acid, and ∝ -naphthaleneacetic acid) 40% of the embryoids developed into plantlets. Further development of the plantlets occured on B5 liquid medium (half strength) + sucrose (1%) + IBA (5 × 10(-7)M) + NAA (10(-7)M).

  20. Bridging the gap between postembryonic cell lineages and identified embryonic neuroblasts in the ventral nerve cord of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Oliver Birkholz

    2015-03-01

    Full Text Available The clarification of complete cell lineages, which are produced by specific stem cells, is fundamental for understanding mechanisms, controlling the generation of cell diversity and patterning in an emerging tissue. In the developing Central Nervous System (CNS of Drosophila, neural stem cells (neuroblasts exhibit two periods of proliferation: During embryogenesis they produce primary lineages, which form the larval CNS. After a phase of mitotic quiescence, a subpopulation of them resumes proliferation in the larva to give rise to secondary lineages that build up the CNS of the adult fly. Within the ventral nerve cord (VNC detailed descriptions exist for both primary and secondary lineages. However, while primary lineages have been linked to identified neuroblasts, the assignment of secondary lineages has so far been hampered by technical limitations. Therefore, primary and secondary neural lineages co-existed as isolated model systems. Here we provide the missing link between the two systems for all lineages in the thoracic and abdominal neuromeres. Using the Flybow technique, embryonic neuroblasts were identified by their characteristic and unique lineages in the living embryo and their further development was traced into the late larval stage. This comprehensive analysis provides the first complete view of which embryonic neuroblasts are postembryonically reactivated along the anterior/posterior-axis of the VNC, and reveals the relationship between projection patterns of primary and secondary sublineages.

  1. A proteomic study to identify soya allergens--the human response to transgenic versus non-transgenic soya samples.

    Science.gov (United States)

    Batista, Rita; Martins, Isabel; Jeno, Paul; Ricardo, Cândido Pinto; Oliveira, Maria Margarida

    2007-01-01

    In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment. Copyright (c) 2007 S. Karger AG, Basel.

  2. Comprehensive analysis of cystatin family genes suggests their putative functions in sexual reproduction, embryogenesis, and seed formation.

    Science.gov (United States)

    Zhao, Peng; Zhou, Xue-mei; Zou, Jie; Wang, Wei; Wang, Lu; Peng, Xiong-bo; Sun, Meng-xiang

    2014-09-01

    Cystatins are tightly bound and reversible inhibitors of cysteine proteases in C1A and C13 peptidase families, which have been identified in several species and shown to function in vegetative development and response to biotic/abiotic stresses in plants. Recent work revealed their critical role in regulating programmed cell death during embryogenesis in tobacco and suggested their more comprehensive roles in the process of sexual plant reproduction, although little is known about cystatin family genes in the processes. Here, 10 cystatin family genes in Nicotiana tabacum were identified using an expressed sequence tag (EST)-based gene clone strategy. Analysis of their biochemical properties showed that nine of them have the potency to inhibit the activities of both commercial cathepsin L-like proteases and extracted cysteine proteases from seeds, but with different K i values depending on the types of proteases and the developmental stages of the seed tested. This suggests that cystatin-dependent cathepsin L-like proteolytic pathways are probably important for early seed development. Comprehensive expression profile analysis revealed that cystatin family genes showed manifold variations in their transcription levels in different plant cell types, including the sperm, egg, and zygote, especially in the embryo and seed at different developmental stages. More interestingly, intracellular localization analysis of each cystatin revealed that most members of cystatin families are recognized as secretory proteins with signal peptides that direct them to the endoplasmic reticulum. These results suggest their widespread roles in cell fate determination and cell-cell communication in the process of sexual reproduction, especially in gamete and embryo development, as well as in seed formation.

  3. Cytomorphological studies on somatic embryogenesis of Gentiana tibetica (King and G. cruciata (L.

    Directory of Open Access Journals (Sweden)

    Anna Mikuła

    2014-02-01

    Full Text Available The process of plant regeneration via somatic embryogenesis of two gentianas, Gentiana tibetica and G. cruciata was described. For this purpose seedling explants were cultured on agar medium and later maintained in cell suspension. For callus initiation seedling explants like: cotyledons, hypocotyl and root were plated on a callus induction medium (CIM composed of MS (1962, supplemented with 0.5 mg/l 2,4-D and 1.0 mg/l Kin. For the formation of cell suspension culture, embryogenic callus was transferred into liquid maintained medium (MM composed of MS (1962, supplemented with 1.0 mg/l Dic + 0.1 mg/l NAA + 2.0 mg/l BAP + 80.0 mg/l SA. The conversion of somatic embryo into plantlets required a new medium (ECM based on MS (1962 mineral salts, supplemented with 0.5 mg/l GA3 + 1.0 mg/l Kin + 0.5 mg/l NAA. For cytomorphological studies of particular stages of embryogenesis, specimens were stained with dyes and reagents: 1. PAS reaction with leukofucsin, 2. Safranin + fast green, 3. Erlich's hematoxylin.

  4. Rape embryogenesis. IV. Appearance and disappearance of starch during embryo development

    Directory of Open Access Journals (Sweden)

    Teresa Tykarska

    2014-01-01

    Full Text Available Starch appears first in the suspensor of the proembryo with two-cell apical part. It is observed in the embryo proper from the octant stage. At first it is visible in all the embryo cells in the form of minute transient grains which disappear during cell divisions. But the columella mother cells and their derivatives have persistent large grains. When the embryo turns green in the heart stage a gradual accumulation of storage starch begins and lasts to the end of embryogenesis. Storage starch grains appear first in the auter cortex layers of the hypocotyl where the largest grains are to be found later, and afterwards in all the other tissues. Starch is usually absent in the frequently dividing cells, but even there it appears in the form of minute grains after the end of cell divisions. Disappearance of starch starts when the intensive green colour of the seed coat begins to fade. The first to disappear are the smallest granules in the regions where they were noted latest. In the embryo axis the starch grains remain deposited longest in dermatogen and cortex cells in the lower hypocotyl part. They are visible there, still when the seed turns brown. In black seeds starch may be only found in the columella the cells of which throughout embryogenesis contain amyloplasts filled with starch. These grains disappear completely at the time when the seeds become dry.

  5. Fgfbp1 is essential for the cellular survival during zebrafish embryogenesis.

    Science.gov (United States)

    Lee, Hae-ock; Choe, Hyerim; Seo, Kyungwoon; Lee, Hyunsook; Lee, Jinseon; Kim, Jhingook

    2010-05-01

    Fibroblast growth factor binding protein 1 (FGFBP1) is expressed in various tumors and may serve as a diagnostic marker and/or a therapeutic target. Previous studies suggested FGFBP1 functions as an angiogenic switch molecule by regulating the activity of FGF2, and it was later found to associate with a broad spectrum of FGFs. To study FGFBP1, we used zebrafish, in which the function of extracellular matrix protein can be easily studied in intact tissues or organisms. When Fgfbp1 expression was knocked down, morphants manifested massive cell death and structural abnormalities. Cell death was most prominent in the brain and the neural tube, but not limited to those regions. These findings suggest that the primary function of Fgfbp1 may be to sustain cellular survival throughout embryogenesis. For comparison, the expression of fgf2 was limited to the early stage of embryogenesis and fgf2 morphants showed more severe phenotype, with high morbidity before reaching 14-somites. Taken together, our work reveals the physiologic function of Fgfbp1, and that its function could be exerted in a Fgf2-independent manner.

  6. Mutation dependance of the mitochondrial DNA copy number in the first stages of human embryogenesis.

    Science.gov (United States)

    Monnot, Sophie; Samuels, David C; Hesters, Laetitia; Frydman, Nelly; Gigarel, Nadine; Burlet, Philippe; Kerbrat, Violaine; Lamazou, Frédéric; Frydman, René; Benachi, Alexandra; Feingold, Josué; Rotig, Agnes; Munnich, Arnold; Bonnefont, Jean-Paul; Steffann, Julie

    2013-05-01

    Mitochondrial DNA (mtDNA) content is thought to remain stable over the preimplantation period of human embryogenesis that is, therefore, suggested to be entirely dependent on ooplasm mtDNA capital. We have explored the impact of two disease-causing mutations [m.3243A>G myopathy, encephalopathy, lactic acidosis and stroke-like syndrome (MELAS) and m.8344A>G myoclonic epilepsy associated with ragged-red fibers (MERRF)] on mtDNA amounts in human oocytes and day 4-5 preimplantation embryos. The mtDNA amount was stable in MERRF and control materials, whereas gradually increasing from the germinal vesicle of oogenesis to the blastocyst stage of embryogenesis in MELAS cells, MELAS embryos carrying ∼3-fold higher mtDNA amount than control embryos (P = 0.0003). A correlation between mtDNA copy numbers and mutant loads was observed in MELAS embryos (R(2) = 0.42, P < 0.0013), suggestive of a compensation for the respiratory chain defect resulting from high mutation levels. These results suggest that mtDNA can replicate in early embryos and emphasize the need for sufficient amount of wild-type mtDNA to sustain embryonic development in humans.

  7. High Efficiency Secondary Somatic Embryogenesis in Hovenia dulcis Thunb. through Solid and Liquid Cultures

    Directory of Open Access Journals (Sweden)

    Jingli Yang

    2013-01-01

    Full Text Available Embryogenic callus was obtained from mature seed explants on medium supplemented with 2,4-dichlorophenoxyacetic acid. Primary somatic embryos (SEs can only develop into abnormal plants. Well-developed SEs could be obtained through secondary somatic embryogenesis both in solid and liquid cultures. Temperature strongly affected induction frequency of secondary embryogenesis. Relatively high temperature (30∘C and germinated SEs explants were effective for induction of secondary somatic embryos, and low temperature (20∘C was more suitable for further embryo development, plantlet conversion, and transplant survival. Somatic embryos formed on agar medium had larger cotyledons than those of embryos formed in liquid medium. Supplementing 0.1 mg L−1 6-benzyladenine (BA was effective for plant conversion; the rate of plant conversion was 43.3% in somatic embryos from solid culture and 36.5% in embryos from liquid culture. In vitro plants were successfully acclimatized in the greenhouse. The protocol established in this study will be helpful for large-scale vegetative propagation of this medicinal tree.

  8. Changes in ecdysteroids during embryogenesis of the blue crab, callinectes sapidus rathbun

    Energy Technology Data Exchange (ETDEWEB)

    McCarthy, J.F.; Skinner, D.M.

    1979-01-01

    Total ecdysteroid titers (estimated by radioimmunoassay (RIA)) in embryos of the blue crab increased from approx. 6 ng 20-hydroxyecdysone equivalents/g in the immature embryo to a maximum of approx. 500 ng 20-hydroxyecdysone equivalents/g in maturing embryos; titers dropped to approx. 300 ng 20-hydroxyecydsone equivalents/g in prehatch embryos. High-pressure reverse-phase chromatography of the embryo extracts resolved five RIA-active components, ..cap alpha..-Ecdysone and the polar conjugate of 20-hydroxyecdysone were present in low quantities. The concentration of 20-hydroxyecdysone increased during embryogenesis to a maximum of approx. 160 ng/g in maturing embryos and decreased only slightly in the prehatch embryos. Two unidentified components were also detected and the changes in their concentrations were estimated. One, an apolar component (peak III), accounted for as much as 63% of the total RIA activity as the embryos matured. The estimated concentration of this component increased from 85 ng/g in early embryos to 475 ng/g in maturing embryos, then decreased by 50% in the prehatch embryos. The level of the other, more polar component (peak II) increased from 7.5 to 75 ng/g as the embryos developed. The increase in the concentration of ecdysteroids during embryogenesis indicates that crab embryos have the capacity to synthesize ecdysteroids and suggests that these hormones may have a physiological role in the embryonic development of crustaceans.

  9. Effect of microgravity and hypergravity on embryo axis alignment during postencystment embryogenesis in Artemia franciscana (Anostraca)

    Science.gov (United States)

    Rosowski, J. R.; Gouthro, M. A.; Schmidt, K. K.; Klement, B. J.; Spooner, B. S.

    1995-01-01

    Cysts of brine shrimp attached with a liquid adhesive to 12-mm diameter glass coverslips in a syringe-type fluid processing apparatus were flown aboard the NASA space shuttle Discovery, flight STS-60, from 3-11 February 1994, and were allowed to undergo postencystment embryogenesis and to hatch in microgravity. The shuttle flight and the ground-based control coverslips with attached cysts were parallel to the earth's surface during incubation in salt water. Based on the position of the cyst shell crack in the attached cyst population, the ground-control nauplii emerged mostly upward. On the shuttle in microgravity, although our method of detection of orientation would not reveal emergence toward the coverslip, the ratio of the position of the cyst shell crack in the population after hatching best fit the predicted values of a random direction for nauplii emergence. Centrifugation on earth was then used to create hypergravity forces of up to 73 g during postencystment embryogenesis and hatching. The upward orientation of emerging nauplii showed a high degree of correlation (r(2) =98.8%) with a linear relationship to the log of g, with 78.2% of the total hatching upward at 1 g and 91.0% hatching upward at 73 g.

  10. Assessment of ploidy stability of the somatic embryogenesis process in Quercus suber L. using flow cytometry.

    Science.gov (United States)

    Loureiro, J; Pinto, G; Lopes, T; Dolezel, J; Santos, C

    2005-08-01

    Flow cytometry analyses were used to verify the ploidy stability of Quercus suber L. somatic embryogenesis process. Leaf explants of two adult cork oak trees (QsG0 and QsG5) of the North of Portugal were inoculated on MS medium with 2,4-D and zeatin. After 3 months, calluses with embryogenic structures were isolated and transferred to fresh MS medium without growth regulators and somatic embryo evolution was followed. Morphologically normal somatic embryos (with two cotyledons) and abnormal somatic embryos (with one or three cotyledons) were used in this assay. Flow cytometry combined with propidium iodide staining was employed to estimate DNA ploidy levels and nuclear DNA content of somatic embryos and leaves from mother plants. No significant differences (P< or =0.05) were detected among embryos, and between the embryos and the mother plants. Also, after conversion of these embryos, no significant morphological differences were observed among the somatic embryo-derived plants. These results and further studies using converted plantlet leaves and embryogenic callus tissue indicate that embryo cultures and converted plantlets were stable with regard to ploidy level. As no major somaclonal variation was detected our primary goal of "true-to-type" propagation of cork oak using somatic embryogenesis was assured at this level. The estimation of the 2C nuclear DNA content for this species is similar to the previously obtained value.

  11. The phosphatidylserine receptor has essential functions during embryogenesis but not in apoptotic cell removal

    Directory of Open Access Journals (Sweden)

    Hafner Martin

    2004-08-01

    Full Text Available Abstract Background Phagocytosis of apoptotic cells is fundamental to animal development, immune function and cellular homeostasis. The phosphatidylserine receptor (Ptdsr on phagocytes has been implicated in the recognition and engulfment of apoptotic cells and in anti-inflammatory signaling. To determine the biological function of the phosphatidylserine receptor in vivo, we inactivated the Ptdsr gene in the mouse. Results Ablation of Ptdsr function in mice causes perinatal lethality, growth retardation and a delay in terminal differentiation of the kidney, intestine, liver and lungs during embryogenesis. Moreover, eye development can be severely disturbed, ranging from defects in retinal differentiation to complete unilateral or bilateral absence of eyes. Ptdsr -/- mice with anophthalmia develop novel lesions, with induction of ectopic retinal-pigmented epithelium in nasal cavities. A comprehensive investigation of apoptotic cell clearance in vivo and in vitro demonstrated that engulfment of apoptotic cells was normal in Ptdsr knockout mice, but Ptdsr-deficient macrophages were impaired in pro- and anti-inflammatory cytokine signaling after stimulation with apoptotic cells or with lipopolysaccharide. Conclusion Ptdsr is essential for the development and differentiation of multiple organs during embryogenesis but not for apoptotic cell removal. Ptdsr may thus have a novel, unexpected developmental function as an important differentiation-promoting gene. Moreover, Ptdsr is not required for apoptotic cell clearance by macrophages but seems to be necessary for the regulation of macrophage cytokine responses. These results clearly contradict the current view that the phosphatidylserine receptor primarily functions in apoptotic cell clearance.

  12. Effects of specific expression of iaaL gene in tobacco tapetum on pollen embryogenesis

    Institute of Scientific and Technical Information of China (English)

    杨洪全; 卫志明; 许智宏

    1997-01-01

    The indoleacetic-acid-lysine synthetase (iaaL) gene from Pseudomonas syringae subsp. savastanoi was fused to tobacco tapetum-specific expression promoter TA29, and introduced into tobacco. The expression pattern of this chimeric gene was studied, and the endogenous indoleacetic acid (IAA) levels in different organs were assayed. The results demonstrated that TA29 promoter was only able to direct the specific expression of iaaL gene in transgenic tobacco anther, and resulted in the decrease of endogenous IAA levels in transgenic tobacco anther. No significant phe-notype variation was observed among the transgenic plants at the whole plant level. However, the percentage of pollen embryogenesis was reduced to 11 % when anthers of the transgenic plants were cultured on the modified hormone-free Nistch H (NH) medium, while those of both CK1 and CK2 (see sec. 1.2.2) were more than 50% ; when the an-thers were cultured on NH medium supplemented with 0. 2 mg/L IAA, the percentage of pollen embryogenesis re-stor

  13. Late recurrence of medulloblastoma.

    Science.gov (United States)

    Stevens, Brittney; Razzaqi, Faisal; Yu, Lolie; Craver, Randall

    2008-01-01

    We present a child with a cerebellar medulloblastoma, diagnosed at age three, treated with near total surgical resection, radiotherapy, and chemotherapy, that recurred 13 years after the initial diagnosis. This late recurrence exceeds the typical 10-year survival statistics that are in common use, and exceeds the Collins rule. Continued follow-up of these children is justified to increase the likelihood of detecting these late recurrences early and to learn more about these late recurrences.

  14. ZLL/AGO10 maintains shoot meristem stem cells during Arabidopsis embryogenesis by down-regulating ARF2-mediated auxin response.

    Science.gov (United States)

    Roodbarkelari, Farshad; Du, Fei; Truernit, Elisabeth; Laux, Thomas

    2015-09-10

    The shoot meristem gives rise to new organs throughout a plant's life by the activity of pluripotent stem cells in the meristem center. Organ initiation at the periphery of the shoot meristem is triggered by the accumulation of the phytohormone auxin at the initiation site. Loss-of-function mutants of the ZWILLE/ARGONAUTE10/PINHEAD (ZLL/AGO10/PNH) gene terminate shoot meristem stem cells late in embryogenesis and can form a leaf or a leaf-like structure instead, indicating that AGO10 activity is required to maintain shoot meristem stem cells undifferentiated. Here, we addressed whether stem cell maintenance by AGO10 involves regulation of auxin. We found that in zll-1 mutants, auxin accumulation and expression of the response reporter DR5:GFP are elevated, and transcription of the Auxin Response Factor 2 (ARF2) gene is upregulated. Downregulation of ARF2 significantly restores stem cells in zll-1 mutants, whereas increased expression of ARF2 enhances differentiation of stem cells in zll-1 mutants. We further found that upregulation of the AGO10 effector gene REVOLUTA restores ARF2 expression and stem cell maintenance in zll-1 embryos. Our results indicate that maintenance of shoot meristem stem cells by AGO10 involves negative regulation of auxin signaling and, via REV-mediated downregulation of ARF2 expression, auxin response.

  15. 陆地棉体细胞胚胎发生过程中基因差异表达%Differential Expression of Genes during Somatic Embryogenesis in Upland Cotton

    Institute of Scientific and Technical Information of China (English)

    Hui-ying LI; Xian-long ZHANG; Yi-chun NIE

    2002-01-01

    @@ Somatic embryogenesis in upland cotton is strongly genotype-dependent, which is a trouble in cotton genetic engineering. Cloning genes related to somatic embryogenesis and then introducing the gene into mainly cultivated varieties would be greatly helpful for cotton improvement by gene transfer. To study the gene expression during somatic embryogenesis will lay a good basis for the cloning of the genes.

  16. Reassessing embryogenesis in the Ctenophora: the inductive role of e1 micromeres in organizing ctene row formation in the 'mosaic' embryo, Mnemiopsis leidyi.

    Science.gov (United States)

    Martindale, M Q; Henry, J Q

    1997-05-01

    Ctenophores are a phylum of diploblastic marine animals displaying biradial symmetry organized along an oral-aboral axis. One of the apomorphic sets of adult structures in ctenophores are the eight external comb rows, which run along the oral-aboral axis. Comb rows consist of serial arrays of individual comb plates of cilia, which beat in a coordinated fashion for locomotory behavior. Classical cell lineage experiments using chalk particles indicated that comb rows are derived exclusively from the four e1 micromeres at the 16-cell stage. This conclusion was also supported by the fact that no ctene rows (or their underlying endodermal canals) form when all four e1 micromeres were deleted. We have used intracellular diI cell lineage tracing to determine that, in addition to e1 micromeres, the four m1 micromeres also make significant contributions to the ctene rows. Thus, e1 micromere derivatives not only generate comb plates but are required for ctene row formation by m1 derivatives. These results demonstrate that inductive interactions are an important component of early development in ctenophores and indicate that e1 micromeres influence the development of adjacent cell lineages (both m1 and endodermal lineages) during ctenophore embryogenesis. In addition, intracellular labeling has revealed that there are subtle variations in the composition of clones derived from identified embryonic blastomeres. Together these findings reveal a picture of ctenophore embryogenesis, which is in marked contrast to the former rigid 'mosaic' reputation of ctenophore development, and invite speculation as to the role of the cleavage program in embryonic patterning in the lower Metazoa.

  17. Personality in Late Midlife

    DEFF Research Database (Denmark)

    Mortensen, Erik Lykke; Flensborg-Madsen, Trine; Molbo, Drude

    2014-01-01

    To analyze associations in late midlife between sex, age, education and social class, and the Big Five personality traits; to analyze associations between personality traits and cognitive ability in late midlife; and to evaluate how these associations are influenced by demographic factors....

  18. Comparing Measures of Late HIV Diagnosis in Washington State

    OpenAIRE

    Laura Saganic; Jason Carr; Rosa Solorio; Maria Courogen; Tom Jaenicke; Ann Duerr

    2011-01-01

    As more US HIV surveillance programs routinely use late HIV diagnosis to monitor and characterize HIV testing patterns, there is an increasing need to standardize how late HIV diagnosis is measured. In this study, we compared two measures of late HIV diagnosis, one based on time between HIV and AIDS, the other based on initial CD4+ results. Using data from Washington's HIV/AIDS Reporting System, we used multivariate logistic regression to identify predictors of late HIV diagnosis. We also con...

  19. EFFECT OF GLUTAMATE MANGANESE ON THE REPRODUCTIVE FUNCTION AND EMBRYOGENESIS OF FEMALE RATS

    Directory of Open Access Journals (Sweden)

    O. V. Shtapenko

    2015-10-01

    Full Text Available Pregnancy is associated with increased nutritional needs due to the physiologic changes of the female and the metabolic demands of the embryo/fetus. The use of chelating compounds with high biological activity increased the fertility of female rats by stimulation metabolism and functional activity of the reproductive system. Manganese is an essential element utilized by antioxidants, including superoxide dismutase (MnSOD, and others metalloenzymes that take part in reduction reactions, in multiple physiological processes including reproductive system. The aim of the research was to determine the effect of subcutaneous injections of Mn glutamate in liposomal forms on the reproductive system and the process of embryogenesis of experimental female rat. The study was conducted on female rats aged 2.5-3 months with body weight of 180-200 g. Rats with dated gestation were divided into three groups: two experimental and control. Female rabbits of the 1th experimental group were subcutaneous injected of 2 mg/ml for Mn glutamate in liposomal form one week before fertilization and the animals of the 2th group were obtained the same preparation during fertilization. Rats were euthanized on the twentieth day, ovariens were singled out of fiber, visual inspection and counting the number of yellow bodies were performed, absolute and relative mass indexes were determined, Mn glutamate influence index was calculated. Experimental results showed that the administration of Mn glutamate 7 days before fertilization and during fertilization significant increased the number of corpora lutea of pregnancy (p<0,001, number of live fetuses (p<0,001 due to the decrease in general and pre-implantation embryonic mortality compared with the control group. The experimental results showed improvement in key indicators of embryonic development. We observed significant increase in the number of implanted embryos on 1 female at 10,7±0,26 and 11,3±0,21 (p<0,001 (9,4±0,16 vs

  20. Progress towards initiation of somatic embryogenesis from differentiated tissues of radiata pine (Pinus radiata D. Don) using cotyledonary embryos

    DEFF Research Database (Denmark)

    Find, Jens Iver; Hargreaves, Cathy L.; Reeves, Catherine B.

    2014-01-01

    of dissected embryos and a modified Litvay medium, Glitz, was best. This combination gave the highest rate of initiation, and it was possible to initiate somatic embryogenesis (SE) from differentiated cells in the epicotyledonary region of postcotyledonary zygotic embryos from the two tested families...

  1. First Report of Plant Regeneration via Somatic Embryogenesis from Shoot Apex-derived Callus of Hedychium muluense

    Science.gov (United States)

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of Hedychium muluense R.M. Smith, an important monocotyledonous ornamental ginger plant. Callus was induced on a modified Murashige and Skoog (MS) medium supplemented with 9.05 µM 2-4, D and 4.6µM kinetin. ...

  2. Enhancing somatic embryogenesis of Malaysian rice cultivar MR219 using adjuvant materials in a high-efficiency protocol

    DEFF Research Database (Denmark)

    Rambod, Abiri; Maziah, Mahmood; Shaharuddin, Noor Azmi

    2017-01-01

    Enhancing of the efficient tissue culture protocol for somatic embryos would facilitate the engineered breeding plants program. In this report, we describe the reproducible protocol of Malaysian rice (Oryza sativa L.) cultivar MR219 through somatic embryogenesis. Effect of a wide spectrum...

  3. DNA methyltransferase expressions in Japanese rice fish (Oryzias latipes) embryogenesis is developmentally regulated and modulated by ethanol and 5-azacytidine

    Science.gov (United States)

    We aimed to investigate the impact of the epigenome in inducting fetal alcohol spectrum disorder (FASD) phenotypes in Japanese rice fish embryogenesis. One of the significant events in epigenome is DNA methylation which is catalyzed by DNA methyl transferase (DNMT) enzymes. We analyzed DNMT enzyme m...

  4. Heterochromia of the irides and a motility disorder of the oesophagus: a coincidence or a defect during embryogenesis?

    Science.gov (United States)

    Goethals, S; Hoffman, I; Devriendt, K; Casteels, I

    2003-01-01

    We present an infant with heterochromia of the irides and a motility disorder of the oesophagus. The association between Hirschsprung's disease and heterochromia of the irides has been reported in the past and has been explained by the common origin during embryogenesis of the parasympathetic ganglion cells and the stroma of the iris.

  5. Novel mitochondria-targeted heat-soluble proteins identified in the anhydrobiotic Tardigrade improve osmotic tolerance of human cells.

    Science.gov (United States)

    Tanaka, Sae; Tanaka, Junko; Miwa, Yoshihiro; Horikawa, Daiki D; Katayama, Toshiaki; Arakawa, Kazuharu; Toyoda, Atsushi; Kubo, Takeo; Kunieda, Takekazu

    2015-01-01

    Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called "anhydrobiosis". Late Embryogenesis Abundant (LEA) proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble) and SAHS (Secretory Abundant Heat Soluble) proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble), as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments.

  6. Novel mitochondria-targeted heat-soluble proteins identified in the anhydrobiotic Tardigrade improve osmotic tolerance of human cells.

    Directory of Open Access Journals (Sweden)

    Sae Tanaka

    Full Text Available Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called "anhydrobiosis". Late Embryogenesis Abundant (LEA proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble and SAHS (Secretory Abundant Heat Soluble proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble, as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments.

  7. Novel Mitochondria-Targeted Heat-Soluble Proteins Identified in the Anhydrobiotic Tardigrade Improve Osmotic Tolerance of Human Cells

    Science.gov (United States)

    Tanaka, Sae; Tanaka, Junko; Miwa, Yoshihiro; Horikawa, Daiki D.; Katayama, Toshiaki; Arakawa, Kazuharu; Toyoda, Atsushi; Kubo, Takeo; Kunieda, Takekazu

    2015-01-01

    Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called “anhydrobiosis”. Late Embryogenesis Abundant (LEA) proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble) and SAHS (Secretory Abundant Heat Soluble) proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble), as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments. PMID:25675104

  8. Loss of CMD2‐mediated resistance to cassava mosaic disease in plants regenerated through somatic embryogenesis

    Science.gov (United States)

    Chauhan, Raj Deepika; Wagaba, Henry; Moll, Theodore; Alicai, Titus; Miano, Douglas; Carrington, James C.; Taylor, Nigel J.

    2016-01-01

    Summary Cassava mosaic disease (CMD) and cassava brown streak disease (CBSD) are the two most important viral diseases affecting cassava production in Africa. Three sources of resistance are employed to combat CMD: polygenic recessive resistance, termed CMD1, the dominant monogenic type, named CMD2, and the recently characterized CMD3. The farmer‐preferred cultivar TME 204 carries inherent resistance to CMD mediated by CMD2, but is highly susceptible to CBSD. Selected plants of TME 204 produced for RNA interference (RNAi)‐mediated resistance to CBSD were regenerated via somatic embryogenesis and tested in confined field trials in East Africa. Although micropropagated, wild‐type TME 204 plants exhibited the expected levels of resistance, all plants regenerated via somatic embryogenesis were found to be highly susceptible to CMD. Glasshouse studies using infectious clones of East African cassava mosaic virus conclusively demonstrated that the process of somatic embryogenesis used to regenerate cassava caused the resulting plants to become susceptible to CMD. This phenomenon could be replicated in the two additional CMD2‐type varieties TME 3 and TME 7, but the CMD1‐type cultivar TMS 30572 and the CMD3‐type cultivar TMS 98/0505 maintained resistance to CMD after passage through somatic embryogenesis. Data are presented to define the specific tissue culture step at which the loss of CMD resistance occurs and to show that the loss of CMD2‐mediated resistance is maintained across vegetative generations. These findings reveal new aspects of the widely used technique of somatic embryogenesis, and the stability of field‐level resistance in CMD2‐type cultivars presently grown by farmers in East Africa, where CMD pressure is high. PMID:26662210

  9. Effect of the "zero" magnetic field on early embryogenesis in mice.

    Science.gov (United States)

    Fesenko, Evgenii E; Mezhevikina, Ludmila M; Osipenko, Marina A; Gordon, Rita Ya; Khutzian, Sergei S

    2010-06-01

    It was shown that the 250-fold screening of the geomagnetic field (GMF) ("zero" magnetic field with an induction of 0.2 muT) affects early embryogenesis and the reproduction capacity of mice in vivo. Pregnant NMRI mice at the zygote stage placed in this "zero" magnetic field (MF) lost the ability to bear offspring babies although their embryos developed up to the blastocyst stage without any visible deviations from the norm. The abortion of development in the "zero" MF occurred after the exit of the blastocysts from the zona pellicida and invasion into the uterus during implantation. Histological analysis indicates that possible reasons of the abnormalities of postimplantation development are a decrease in the proliferative activity of embryonic cells and the impairment of the interaction between the trophoblast and endometrium, which finally results in the resorption of embryos in the uterus.

  10. Microspore Embryogenesis Through Anther Culture in Citrus clementina Hort. ex Tan.

    Science.gov (United States)

    Chiancone, Benedetta; Germanà, Maria Antonietta

    2016-01-01

    Anther culture is a biotechnological method that allows to obtain, in one step, homozygous plants, very important to plant breeding, due to their numerous applications in mutation research, selection, genome sequencing, genetic analysis, and transformation. To induce the microspores, i.e., the immature male gametes, to switch from the normal gametophytic pathway to the sporophytic one, it is necessary to submit them to a type of stress, such as high or low temperature, starvation, or magnetic field. Stress can be applied to the donor plants and/or the floral buds or the anthers or the isolated microspores, before or during the culture. In this chapter, the protocol to induce gametic embryogenesis from anther culture of several cultivars of Citrus clementina Hort. ex Tan. is reported.

  11. Auxin distribution and transport during embryogenesis and seed germi-nation of Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Auxin distribution during embryogenesis and seed germination were studied with transgenic Arabidopsis plants expressing GUS gene driven by a synthetic DR5 promoter, an auxin responsive promoter. The results showed that GUS activity is higher in ends of hypophysis and cotyledon primordia of heart-, torpedo- and cotyledon-stage embryos, leaf tip area, lateral root primordia, root apex and cotyledon of young seedlings.And GUS accumulated in root apex of the seedlings grown on auxin transport inhibitor containing media.All these suggested that above-mentioned part of the organs and tissues have a higher level of auxin, and auxin polar transport inhibitor could cause the accumulation of auxin in root apex. And auxin transport inhibitor also resulted in aberration of Arabidopsis leaf pattern formation, root gravitropism and elongation.

  12. Dual lineage-specific expression of Sox17 during mouse embryogenesis

    DEFF Research Database (Denmark)

    Choi, Eunyoung; Kraus, Marine R C; Lemaire, Laurence A

    2012-01-01

    Sox17 is essential for both endoderm development and fetal hematopoietic stem cell (HSC) maintenance. While endoderm-derived organs are well known to originate from Sox17-expressing cells, it is less certain whether fetal HSCs also originate from Sox17-expressing cells. By generating a Sox17(GFPCre......) allele and using it to assess the fate of Sox17-expressing cells during embryogenesis, we confirmed that both endodermal and a part of definitive hematopoietic cells are derived from Sox17-positive cells. Prior to E9.5, the expression of Sox17 is restricted to the endoderm lineage. However, at E9.5 Sox17...... is expressed in the endothelial cells (ECs) at the para-aortic splanchnopleural region that contribute to the formation of HSCs at a later stage. The identification of two distinct progenitor cell populations that express Sox17 at E9.5 was confirmed using fluorescence-activated cell sorting together with RNA...

  13. Plant regeneration through somatic embryogenesis from callus induced on immature embryos of Alstroemeria spp. L.

    Science.gov (United States)

    Van Schaik, C E; Posthuma, A; De Jeu, M J; Jacobsen, E

    1996-01-01

    The plant regeneration ability of callus obtained from zygotic embryos of the monocot Alstroemeria spp. was studied. The best explants for somatic embryogenesis were immature zygotic embryos in half-ovules when the endosperm was still soft and white. For 2 genotypes embryogenic callus was induced on callus induction medium with a success rate of 54%. The best callus induction period was 10 weeks. The morphology of embryogenic callus was nodular. Somatic embryos were formed after transfer of the callus to regeneration medium. These somatic embryos revealed later on the typical features of zygotic Alstroemeria embryos. The total duration of the plant regeneration protocol, from inoculation till rooted plantlets ready for transfer to the greenhouse, was 28 weeks.

  14. Dedifferentiating initiation and embryogenesis from freshly-isolated microspores of barley

    Institute of Scientific and Technical Information of China (English)

    郭向荣; 景建康; 胡含

    1997-01-01

    By using DNA-specific fluorescent dye and a confocal laser scanning microscope, the present study was designed to investigate the cytological characteristics of dedifferentiating initiation during pretreatment and em-bryogenesis during culture in freshly-isolated microspores of barley, and the difference in main developmental pathway between freshly-isolated and cold-treated microspores. The results revealed that ( i ) freshly-isolated microspores started the initiation within 12 h of mannitol pretreatment, whose main cytological characteristics were that: cell vol-ume was obviously extended; the volume of nuclei and nucleoli were also greatly increased; nucleoli were extremely clear and highly condensed; N/C ratio was very high; ( ii ) all the pretreatment methods led to the initiation of the mi-crospores, thus triggering the embryogenic process; ( iii ) pretreatment methods influenced the main developmental pathway of microspores by changing the pattern of the first mitosis. The cold-treated microspor

  15. A cell-based computational model of early embryogenesis coupling mechanical behaviour and gene regulation.

    Science.gov (United States)

    Delile, Julien; Herrmann, Matthieu; Peyriéras, Nadine; Doursat, René

    2017-01-23

    The study of multicellular development is grounded in two complementary domains: cell biomechanics, which examines how physical forces shape the embryo, and genetic regulation and molecular signalling, which concern how cells determine their states and behaviours. Integrating both sides into a unified framework is crucial to fully understand the self-organized dynamics of morphogenesis. Here we introduce MecaGen, an integrative modelling platform enabling the hypothesis-driven simulation of these dual processes via the coupling between mechanical and chemical variables. Our approach relies upon a minimal 'cell behaviour ontology' comprising mesenchymal and epithelial cells and their associated behaviours. MecaGen enables the specification and control of complex collective movements in 3D space through a biologically relevant gene regulatory network and parameter space exploration. Three case studies investigating pattern formation, epithelial differentiation and tissue tectonics in zebrafish early embryogenesis, the latter with quantitative comparison to live imaging data, demonstrate the validity and usefulness of our framework.

  16. THE EFFECT OF PICLORAM AND LIGHT ON SOMATIC EMBRYOGENESIS REGENERATION OF PINEAPPLE

    Directory of Open Access Journals (Sweden)

    Ika Roostika

    2012-10-01

    Full Text Available Smooth Cayenne is the largest pineapple type cultivated in Indonesia, but its vegetative planting materials for mass propagation are limited. Somatic embryogenesis is a potential method to be applied. The aim of this study was to investigate the somatic embryogenesis regeneration under the effect of picloram and light. Callus formation was induced by picloram (21, 41 and 62 μM added with 9 μM thidiazuron. The calli were transferred onto MS or Bac medium  enriched with N-organic compounds with or without addition of 21 μM picloram under dark or light condition. The compact calli were subcultured onto MS medium supplemented with 4.65 μM kinetin, while the friable calli were  transferred onto BIG medium (modified MS + 1.1 μM benzyl adenine + 0.9 μM indole butyric acid + 0.09 μM giberelic acid or B medium (MS + 0.018 mM benzyl adenine. The results showed that the events of somatic embryogenesis were started from cell polarization, asymmetrical division, proembryo formation as  embryogenic tissues and friable embryogenic tissues, and embryo development. The best treatment for callus induction was 21 μM picloram. The addition of 21 μM picloram on N-organic enriched medium and the use of light condition  proliferated embryogenic calli. The N-organic enriched Bac medium and light condition yielded the highest number of mature somatic embryos (17 embryos perexplant in 2 months. The B medium was better than BIG medium to develop  somatic embryos from friable embryogenic tissues. The somatic embryogenesis method presented is potential for pineapple mass propagation and artificial seedproduction.Abstrak Bahasa IndonesiaSmooth Cayenne merupakan kultivar nenas yang banyak dibudidayakan di  Indonesia, namun ketersediaan benih untuk perbanyakan massal masih terbatas. Embriogenesis somatikadalah metode yang potensial untuk produksi bibit secara massal. Tujuan penelitian adalah untuk mempelajari pengaruh pikloram dan pencahayaan terhadap regenerasi

  17. A cell-based computational model of early embryogenesis coupling mechanical behaviour and gene regulation

    Science.gov (United States)

    Delile, Julien; Herrmann, Matthieu; Peyriéras, Nadine; Doursat, René

    2017-01-01

    The study of multicellular development is grounded in two complementary domains: cell biomechanics, which examines how physical forces shape the embryo, and genetic regulation and molecular signalling, which concern how cells determine their states and behaviours. Integrating both sides into a unified framework is crucial to fully understand the self-organized dynamics of morphogenesis. Here we introduce MecaGen, an integrative modelling platform enabling the hypothesis-driven simulation of these dual processes via the coupling between mechanical and chemical variables. Our approach relies upon a minimal `cell behaviour ontology' comprising mesenchymal and epithelial cells and their associated behaviours. MecaGen enables the specification and control of complex collective movements in 3D space through a biologically relevant gene regulatory network and parameter space exploration. Three case studies investigating pattern formation, epithelial differentiation and tissue tectonics in zebrafish early embryogenesis, the latter with quantitative comparison to live imaging data, demonstrate the validity and usefulness of our framework.

  18. Somatic Embryogenesis and Plant Regeneration from Cultured Immature Embryos of Rye (Secale cereale L.).

    Science.gov (United States)

    Lu, C Y; Chandler, S F; Vasil, I K

    1984-07-01

    Somatic embryogenesis was initiated in immature embryos of rye (Secale cereale L.) cultured on Murashige and Skoog's (1962) medium supplemented with various concentrations of 2,4-D and sucrose. The developmental stage of the embryo (optimal embryo length 0.5-2.0 mm) and concentration of 2,4-D (optimal concentration 2.5 mg · l(-1)) were found to be critical in determining embryo response. The phenoxyacetic acids, 2,4-D, 2,4,5-T, and MCPA were more effective in initiating embryogenic callus and embryoid formation than other auxins (NAA, IBA, IAA, IPA). Embryogenic callus and embryoid production was greater in embryos cultured scutellum up, and more embryoids were formed in the dark than in the light. Embryoids germinated after transfer to basal medium with/without cytokinin or GA3. The regenerated plants were grown to maturity in soil and were shown to have the normal diploid chromosome number of 14.

  19. In vitro organogenesis and somatic embryogenesis from leaf explants of Leucosceptrum canum sm.

    Science.gov (United States)

    Pal, A; Banerjee, A; Dhar, K

    1985-10-01

    Plantlets were obtained from leaf explants of a Labiatae tree - Leucosceptrum canum Sm. using plant tissue culture techniques. Two types of calli proliferated from the leaf explants when grown on different media, one of which was amenable to somatic embryogenesis. Differentiation of the embryoids started from the fourth passage of culture and continued up to the seventh passage. The number of embryoids decreased with the age of the callus. The capacity of such embryoids to form entire plantlets was studied using different nutrient mileux. Embryoids formed plantlets on Murashige and Skoog's (MS) medium fortified with benzylaminopurine plus indolebutyric acid. Organogenesis was observed in shoot-buds derived from explants of in vitro regenerated plantlets on MS basal medium supplemented with benzylaminopurine. Culture regenerated plantlets were transferred to MS medium without sucrose and growth hormones; finally transferred to pots containing sterile vermiculite where they are growing.

  20. Plant regeneration by pollen embryogenesis from cultured whole spikes of barley (Hordeum vulgare).

    Science.gov (United States)

    Datta, S K

    1987-05-01

    Pollen embryogenesis and subsequent plant regeneration have been established from cultured whole barley spikes in agitated N6 liquid medium (Chu 1978) containing high levels of 2,4-D, Ficoll and potato extract. Microspore division within the anthers and subsequent embryogenic development were obtained in medium containing high amounts of reduced nitrogen with Zeatin, NAA and BAP (all at 0.5 mg/l levels, pH 6.2). Once embryoids were formed in the liquid medium, they produced secondary embryoids from the scutellum and subsequently plants on MS (Murashige and Skoog 1962) agar medium containing BAP and NAA. The ratio of green plants to albino was 1∶8.7.

  1. A transgenic quail model that enables dynamic imaging of amniote embryogenesis.

    Science.gov (United States)

    Huss, David; Benazeraf, Bertrand; Wallingford, Allison; Filla, Michael; Yang, Jennifer; Fraser, Scott E; Lansford, Rusty

    2015-08-15

    Embryogenesis is the coordinated assembly of tissues during morphogenesis through changes in individual cell behaviors and collective cell movements. Dynamic imaging, combined with quantitative analysis, is ideal for investigating fundamental questions in developmental biology involving cellular differentiation, growth control and morphogenesis. However, a reliable amniote model system that is amenable to the rigors of extended, high-resolution imaging and cell tracking has been lacking. To address this shortcoming, we produced a novel transgenic quail that ubiquitously expresses nuclear localized monomer cherry fluorescent protein (chFP). We characterize the expression pattern of chFP and provide concrete examples of how Tg(PGK1:H2B-chFP) quail can be used to dynamically image and analyze key morphogenetic events during embryonic stages X to 11.

  2. 栓皮栎体胚诱导关键影响因素研究%Factors Influencing the Induction of Somatic Embryogenesis in Quercus variabilis

    Institute of Scientific and Technical Information of China (English)

    张存旭; 姚增玉; 赵忠

    2005-01-01

    Immature zygotic embryos of Quercus variabilis were as explants to induce somatic embryogenesis. Several factors influencing somatic embryogenesis have been assayed. Somatic embryos can be induced in MS and WPM basal medium, but there was more quantity, big size and high induction rate in MS medium. Induction rate was not significant cultured in light and dark condition. Zygotic embryos, collected in middle of July, gave higher rate of somatic embryogenesis than those collected on the earlier or later date. By adding 6-BA in medium individually, somatic embryogenesis appeared directly on the zygotic embryos without detectable callus. Secondary embryogenesis appeared in medium with 2,4-D individual or combined with 6-BA or TDZ. High induction frequency of 90% was achieved in MS medium supplemented with O. 5 mg·L-1 6-BA and 2,4-D, whereas the rate in hormone-free medium was only 16.7%. The genotypes of mother trees had an great impact on the inducing rate. Zygotic embryo surgery treatments were not favorable to embryogenesis. It was best to inoculate with entire zygotic embryos. The hypocotyl was a crucial part on somatic embryogenesis for Q. variabilis.

  3. Expression of PiABP19, Picdc2 and PiSERK3 during induction of somatic embryogenesis in leaflets of Prunus incisa (Thunb.).

    Science.gov (United States)

    Ben Mahmoud, Kaouther; Delporte, Fabienne; Muhovski, Yordan; Elloumi, Nadhra; Jemmali, Ahmed; Druart, Philippe

    2013-02-01

    Somatic embryogenesis is a useful tool of plant breeding. In this context, a procedure for inducing somatic embryogenesis in Prunus incisa leaf explants had been previously developed. The original in vitro protocol relies on picloram treatments and exposure to darkness as inductive conditions, the best frequency of embryogenesis being obtained on the second leaf (F(2)) exposed to 4 μM picloram during 30 days. The morphological and biochemical changes observed during somatic embryogenesis occur in response to alterations in gene expression regulation patterns. A molecular study was conducted in order to provide deeper insight into the fundamental biological factors involved in the induction of this process using a gene candidate strategy and semi-quantitative reverse transcription polymerase chain reaction analysis. So far, no sequence data related to somatic embryogenesis has been available in cherry. In the present study, we cloned and sequenced cDNA fragments of putative genes encoding auxin-binding protein, cell cycle regulator and somatic embryogenesis receptor kinase. Time-course differential transcript accumulations were observed for all investigated genes in leaves or derived callus tissues during the observation period (first month of culture). Their possible involvement in the sequential steps of the embryogenic pathway (dedifferentiation, cell proliferation, differentiation through somatic embryogenesis) is presented and discussed.

  4. The polarity protein Par6 is coupled to the microtubule network during molluscan early embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Taihei [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Shimizu, Miho [Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Kuroda, Reiko, E-mail: ckuroda@mail.ecc.u-tokyo.ac.jp [Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902 (Japan); Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902 (Japan)

    2011-01-07

    Research highlights: {yields} The cDNAs encoding Par6 and aPKC homologues were cloned from the snail Lymnaea stagnalis. {yields} L. stagnalis Par6 directly interacts with tubulin and microtubules and localizes to the microtubule cytoskeleton during the early embryogenesis. {yields} Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of body handedness. -- Abstract: Cell polarity, which directs the orientation of asymmetric cell division and segregation of fate determinants, is a fundamental feature of development and differentiation. Regulators of polarity have been extensively studied, and the critical importance of the Par (partitioning-defective) complex as the polarity machinery is now recognized in a wide range of eukaryotic systems. The Par polarity module is evolutionarily conserved, but its mechanism and cooperating factors vary among different systems. Here we describe the cloning and characterization of a pond snail Lymnaea stagnalis homologue of partitioning-defective 6 (Lspar6). The protein product LsPar6 shows high affinity for microtubules and localizes to the mitotic apparatus during embryonic cell division. In vitro assays revealed direct binding of LsPar6 to tubulin and microtubules, which is the first evidence of the direct interaction between the two proteins. The interaction is mediated by two distinct regions of LsPar6 both located in the N-terminal half. Atypical PKC, a functional partner of Par6, was also found to localize to the mitotic spindle. These results suggest that the L. stagnalis Par complex employs the microtubule network in cell polarity processes during the early embryogenesis. Identical sequence and localization of LsPar6 for the dextral and the sinistral snails exclude the possibility of the gene being the primary determinant of handedness.

  5. Developmental toxicity of endocrine disruptors in early life stages of zebrafish, a genetic and embryogenesis study.

    Science.gov (United States)

    Santos, Dércia; Matos, Manuela; Coimbra, Ana M

    2014-01-01

    Endocrine disrupting compounds (EDCs) are capable of interfering with the endocrine system and are increasingly widespread in the aquatic environments. In the present study, zebrafish (Danio rerio) embryos and larvae were used to assess how EDCs may interfere with embryogenesis. Therefore, zebrafish embryos were exposed to 17α-ethinylestradiol (EE2: 0.4, 2, 4 and 20 ng/L), genistein (Gen: 2, 20, 200 and 2000 ng/L) and fadrozole (Fad: 2, 10, 50 and 250 μg/L), between 2 and 144 h post-fertilization (hpf). Somite development, heartbeat, malformations, mortality and hatching rates were evaluated. In parallel, the expression patterns of hormone receptors (esr1, esr2a, esr2b and ar) and apoptotic pathways related genes (p53 and c-jun) were determined using quantitative real-time PCR. Results showed that EE2, Gen and Fad caused a higher mortality and also malformations in larvae compared with control. A significant toxic effect was observed in the heartbeat rate, at 144 hpf, in larvae exposed to EE2 and Fad. QPCR revealed alterations in the expression levels of all the evaluated genes, at different time points. esr1 and c-jun genes were upregulated by EE2 and Gen exposure while the expression of esr2a, esr2b and ar genes was downregulated. Fad exposure decreased esr1, p53 and c-jun expression levels. This study shows a toxic effect of EE2, Gen and Fad to vertebrate embryogenesis and a relation between hormones action and apoptosis pathways.

  6. Plant Regeneration and Somatic Embryogenesis from Immature Embryos Derived through Interspecific Hybridization among Different Carica Species

    Directory of Open Access Journals (Sweden)

    Latifah Amin

    2012-12-01

    Full Text Available Plant regeneration and somatic embryogenesis through interspecific hybridization among different Carica species were studied for the development of a papaya ringspot virus-resistant variety. The maximum fruit sets were recorded from the cross of the native variety C. papaya cv. Shahi with the wild species C. cauliflora. The highest hybrid embryos were recorded at 90 days after pollination and the embryos were aborted at 150 days after pollination. The immature hybrid embryos were used for plant regeneration and somatic embryogenesis. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora showed the highest percentage of germination, as well as plant regeneration on growth regulators free culture medium after 7 days pre-incubation on half-strength MS medium supplemented with 0.2 mg/L BAP, 0.5 mg/L NAA and 60 g/L sucrose. The 90-day-old hybrid embryos from the cross of C. papaya cv. Shahi × C. cauliflora produced maximum callus, as well as somatic embryos when cultured on half-strength MS medium containing 5 mg/L 2,4-D, 100 mg/L glutamine, 100 mg/L casein hydrolysate and 60 g/L sucrose. The somatic embryos were transferred into half-strength MS medium containing 0.5 mg/L BAP and 0.2 mg/L NAA and 60 g/L sucrose for maturation. The highest number of regenerated plants per hybrid embryo (10.33 was recorded from the cross of C. papaya cv. Shahi × C. cauliflora. Isoenzyme and dendrogram cluster analysis using UPGMA of the regenerated F1 plantlets confirmed the presence of the hybrid plantlets.

  7. Ixodes pacificus ticks maintain embryogenesis and egg hatching after antibiotic treatment of Rickettsia endosymbiont.

    Science.gov (United States)

    Kurlovs, Andre H; Li, Jinze; Cheng, Du; Zhong, Jianmin

    2014-01-01

    Rickettsia is a genus of intracellular bacteria that causes a variety of diseases in humans and other mammals and associates with a diverse group of arthropods. Although Rickettsia appears to be common in ticks, most Rickettsia-tick relationships remain generally uncharacterized. The most intimate of these associations is Rickettsia species phylotype G021, a maternally and transstadially transmitted endosymbiont that resides in 100% of I. pacificus in California. We investigated the effects of this Rickettsia phylotype on I. pacificus reproductive fitness using selective antibiotic treatment. Ciprofloxacin was 10-fold more effective than tetracycline in eliminating Rickettsia from I. pacificus, and quantitative PCR results showed that eggs from the ciprofloxacin-treated ticks contained an average of 0.02 Rickettsia per egg cell as opposed to the average of 0.2 in the tetracycline-treated ticks. Ampicillin did not significantly affect the number of Rickettsia per tick cell in adults or eggs compared to the water-injected control ticks. We found no relationship between tick embryogenesis and rickettsial density in engorged I. pacificus females. Tetracycline treatment significantly delayed oviposition of I. pacificus ticks, but the antibiotic's effect was unlikely related to Rickettsia. We also demonstrated that Rickettsia-free eggs could successfully develop into larvae without any significant decrease in hatching compared to eggs containing Rickettsia. No significant differences in the incubation period, egg hatching rate, and the number of larvae were found between any of the antibiotic-treated groups and the water-injected tick control. We concluded that Rickettsia species phylotype G021 does not have an apparent effect on embryogenesis, oviposition, and egg hatching of I. pacificus.

  8. Disruption of circulation by ethanol promotes fetal alcohol spectrum disorder (FASD) in medaka (Oryzias latipes) embryogenesis.

    Science.gov (United States)

    Hu, Yuhui; Khan, Ikhlas A; Dasmahapatra, Asok K

    2008-09-01

    Japanese medaka (Oryzias latipes) embryos exposed to ethanol have developed craniofacial, cardiovascular and skeletal defects which can be compared with the phenotypic features of fetal alcohol spectrum disorder (FASD) observed in human. The present experiment was designed to show that the disruption in circulation by ethanol during embryogenesis is a potential cause of FASD. Fertilized eggs were exposed to ethanol (0, 100 and/or 400 mM) for 24 or 48 h at various developmental stages (Iwamatsu stages 4-30) and were analyzed at 6 day post fertilization (dpf). It was observed that controls and the embryos exposed to 100 mM ethanol were in circulating state; however, a significant number of embryos of stages 4-24 exposed to 400 mM ethanol had disrupted circulation. Compared to controls, protein and RNA contents were significantly reduced in non-circulating embryos. Lipid peroxidation (LPO) analysis was made at 3, 6, 24, 48, 96 and 144 hour post fertilization (hpf). LPO was increased with the advancement of morphogenesis; however, ethanol or the circulation status had no effect. We further analyzed alcohol dehydrogenase (Adh 5 and adh8) and aldehyde dehydrogenase (Aldh9A and Aldh1A2) enzyme mRNAs in the embryos exposed to 400 mM ethanol for 24 h. A developmental stage-specific reduction in these enzyme mRNAs by ethanol was observed. We conclude that ethanol-induced disruption in circulation during embryogenesis is a potential cause of the development of FASD features in medaka.

  9. Thermal manipulation during embryogenesis affects myoblast proliferation and skeletal muscle growth in meat-type chickens.

    Science.gov (United States)

    Piestun, Yogev; Yahav, Shlomo; Halevy, Orna

    2015-10-01

    Thermal manipulation (TM) of 39.5°C applied during mid-embryogenesis (embryonic d 7 to 16) has been proven to promote muscle development and enhance muscle growth and meat production in meat-type chickens. This study aimed to elucidate the cellular basis for this effect. Continuous TM or intermittent TM (for 12 h/d) increased myoblast proliferation manifested by higher (25 to 48%) myoblast number in the pectoral muscles during embryonic development but also during the first week posthatch. Proliferation ability of the pectoral-muscle-derived myoblasts in vitro was significantly higher in the TM treatments until embryonic d 15 (intermittent TM) or 13 (continuous TM) compared to that of controls, suggesting increased myogenic progeny reservoir in the muscle. However, the proliferation ability of myoblasts was lower in the TM treatments vs. control during the last days of incubation. This coincided with higher levels of myogenin expression in the muscle, indicating enhanced cell differentiation in the TM muscle. A similar pattern was observed posthatch: Myoblast proliferation was significantly higher in the TM chicks relative to controls during the peak of posthatch cell proliferation until d 6, followed by lower cell number 2 wk posthatch as myoblast number sharply decreases. Higher myogenin expression was observed in the TM chicks on d 6. This resulted in increased muscle growth, manifested by significantly higher relative weight of breast muscle in the embryo and posthatch. It can be concluded that temperature elevation during mid-term embryogenesis promotes myoblast proliferation, thus increasing myogenic progeny reservoir in the muscle, resulting in enhanced muscle growth in the embryo and posthatch. © 2015 Poultry Science Association Inc.

  10. A microarray approach to identify genes involved in seed-pericarp cross-talk and development in peach

    Directory of Open Access Journals (Sweden)

    Zaffalon Valerio

    2011-06-01

    Full Text Available Abstract Background Field observations and a few physiological studies have demonstrated that peach embryogenesis and fruit development are tightly coupled. In fact, attempts to stimulate parthenocarpic fruit development by means of external tools have failed. Moreover, physiological disturbances during early embryo development lead to seed abortion and fruitlet abscission. Later in embryo development, the interactions between seed and fruit development become less strict. As there is limited genetic and molecular information about seed-pericarp cross-talk and development in peach, a massive gene approach based on the use of the μPEACH 1.0 array platform and quantitative real time RT-PCR (qRT-PCR was used to study this process. Results A comparative analysis of the transcription profiles conducted in seed and mesocarp (cv Fantasia throughout different developmental stages (S1, S2, S3 and S4 evidenced that 455 genes are differentially expressed in seed and fruit. Among differentially expressed genes some were validated as markers in two subsequent years and in three different genotypes. Seed markers were a LTP1 (lipid transfer protein, a PR (pathogenesis-related protein, a prunin and LEA (Late Embryogenesis Abundant protein, for S1, S2, S3 and S4, respectively. Mesocarp markers were a RD22-like protein, a serin-carboxypeptidase, a senescence related protein and an Aux/IAA, for S1, S2, S3 and S4, respectively. The microarray data, analyzed by using the HORMONOMETER platform, allowed the identification of hormone-responsive genes, some of them putatively involved in seed-pericarp crosstalk. Results indicated that auxin, cytokinins, and gibberellins are good candidates, acting either directly (auxin or indirectly as signals during early development, when the cross-talk is more active and vital for fruit set, whereas abscisic acid and ethylene may be involved later on. Conclusions In this research, genes were identified marking different phases of

  11. Late-Stage Caregiving

    Science.gov (United States)

    ... resources, care and ways to engage in meaningful connections. During the late stages, your role as a ... drinks. This will help you track the person's natural routine, and then you can plan a schedule. ...

  12. Suicides in late life.

    Science.gov (United States)

    Van Orden, Kimberly; Conwell, Yeates

    2011-06-01

    Suicide in late life is an enormous public health problem that will likely increase in severity as adults of the baby boom generation age. Data from psychological autopsy studies supplemented with recent studies of suicidal ideation and attempts point to a consistent set of risk factors for the spectrum of suicidal behaviors in late life (suicide ideation, attempts, and deaths). Clinicians should be vigilant for psychiatric illness (especially depression), physical illness, pain, functional impairment, and social disconnectedness. Recent advances in late-life suicide prevention have in common collaborative, multifaceted intervention designs. We suggest that one mechanism shared by all preventive interventions shown to reduce the incidence of late-life suicide is the promotion of connectedness. For the clinician working with older adults, our recommendation is to not only consider risk factors, such as depression, and implement appropriate treatments but to enhance social connectedness as well.

  13. Comparing Measures of Late HIV Diagnosis in Washington State

    Directory of Open Access Journals (Sweden)

    Laura Saganic

    2012-01-01

    Full Text Available As more US HIV surveillance programs routinely use late HIV diagnosis to monitor and characterize HIV testing patterns, there is an increasing need to standardize how late HIV diagnosis is measured. In this study, we compared two measures of late HIV diagnosis, one based on time between HIV and AIDS, the other based on initial CD4+ results. Using data from Washington's HIV/AIDS Reporting System, we used multivariate logistic regression to identify predictors of late HIV diagnosis. We also conducted tests for trend to determine whether the proportion of cases diagnosed late has changed over time. Both measures lead us to similar conclusions about late HIV diagnosis, suggesting that being male, older, foreign-born, or heterosexual increase the likelihood of late HIV diagnosis. Our findings reaffirm the validity of a time-based definition of late HIV diagnosis, while at the same time demonstrating the potential value of a lab-based measure.

  14. Somatic embryogenesis and plant regeneration from immature zygotic embryos of Hinoki cypress (Chamaecyparis obtusa Sieb. et Zucc.).

    Science.gov (United States)

    Taniguchi, T; Kurita, M; Itahana, N; Kondo, T

    2004-08-01

    We established a plant regeneration system for Hinoki cypress (Chamaecyparis obtusa) via somatic embryogenesis. Embryogenic tissues were successfully induced on three kinds of Smith media from megagametophyte explants containing pre-cotyledonary embryos of C. obtusa plus-trees. Factors affecting somatic embryo maturation were examined. The concentration of polyethylene glycol 4000 in the medium was a critical factor for embryo maturation and its effective concentration was 150 g/l. The addition of 30 g/l maltose to the medium had a positive effect on embryo maturation, but sucrose was ineffective. The mature somatic embryos germinated at a germination frequency of approximately 60%, and the presence of activated charcoal was effective in stimulating plantlet growth. The plantlets acclimatized successfully in a greenhouse. To our knowledge, this is first report describing details of a plant regeneration method for C. obtusa via somatic embryogenesis.

  15. One type of chalcone synthase gene expressed during embryogenesis regulates the flavonoid accumulation in citrus cell cultures.

    Science.gov (United States)

    Moriguchi, T; Kita, M; Tomono, Y; EndoInagaki, T; Omura, M

    1999-06-01

    To elucidate the relationship between the expression of chalcone synthase (CHS) genes and the production of flavonoid in citrus cell cultures, two cDNA clones encoding CHS were isolated (CitCHS1 and CitCHS2) from the citrus. The accumulation of CitCHS2 mRNA was notably induced by embryogenesis but CitCHS1 mRNA was not. There was no detectable accumulation of flavonoid in the undifferentiated calli, but flavonoid accumulated after the morphological changes to embryoids. These results indicate that two CHS genes differentially expressed during citrus somatic embryogenesis and CitCHS2 may regulate the accumulation of flavonoid in citrus cell cultures.

  16. Characterization of expressed sequence tags obtained by SSH during somatic embryogenesis in Cichorium intybus L

    Directory of Open Access Journals (Sweden)

    Quillet Marie-Christine

    2007-06-01

    Full Text Available Abstract Background Somatic embryogenesis (SE is an asexual propagation pathway requiring a somatic-to-embryonic transition of differentiated somatic cells toward embryogenic cells capable of producing embryos in a process resembling zygotic embryogenesis. In chicory, genetic variability with respect to the formation of somatic embryos was detected between plants from a population of Cichorium intybus L. landrace Koospol. Though all plants from this population were self incompatible, we managed by repeated selfing to obtain a few seeds from one highly embryogenic (E plant, K59. Among the plants grown from these seeds, one plant, C15, was found to be non-embryogenic (NE under our SE-inducing conditions. Being closely related, we decided to exploit the difference in SE capacity between K59 and its descendant C15 to study gene expression during the early stages of SE in chicory. Results Cytological analysis indicated that in K59 leaf explants the first cell divisions leading to SE were observed at day 4 of culture. In contrast, in C15 explants no cell divisions were observed and SE development seemed arrested before cell reactivation. Using mRNAs isolated from leaf explants from both genotypes after 4 days of culture under SE-inducing conditions, an E and a NE cDNA-library were generated by SSH. A total of 3,348 ESTs from both libraries turned out to represent a maximum of 2,077 genes. In silico subtraction analysis sorted only 33 genes as differentially expressed in the E or NE genotype, indicating that SSH had resulted in an effective normalisation. Real-time RT-PCR was used to verify the expression levels of 48 genes represented by ESTs from either library. The results showed preferential expression of genes related to protein synthesis and cell division in the E genotype, and related to defence in the NE genotype. Conclusion In accordance with the cytological observations, mRNA levels in explants from K59 and C15 collected at day 4 of SE

  17. Effect of heparan sulfate and gold nanoparticles on muscle development during embryogenesis

    Directory of Open Access Journals (Sweden)

    Zielinska M

    2011-12-01

    Full Text Available Marlena Zielinska1,2, Ewa Sawosz1, Marta Grodzik1, Mateusz Wierzbicki1, Maria Gromadka1, Anna Hotowy3, Filip Sawosz3, Andrzej Lozicki1, Andrè Chwalibog31Division of Biotechnology and Biochemistry of Nutrition, Warsaw University of Life sciences, Warsaw, 2The Kielanowski Institute of Animal Physiology and Nutrition, Jablonna, Poland; 3Department of Basic Animal and Veterinary sciences, University of copenhagen, Frederiksberg, DenmarkPurpose: It was hypothesized that heparan sulfate (HS as an essential compound for myogenesis and nanoparticles of gold (nano-Au as highly reactive compounds can affect muscle development as a consequence of molecular regulation of muscle cell formation, and that these effects may be enhanced by a complex of HS conjugated with nano-Au. The objective of the present study was to determine the effect of administration of nano-Au, HS, and a nano-Au+HS complex on the morphological and molecular characteristics of breast muscle during embryogenesis.Methods: Chicken embryos were used as in vivo model. Fertilized chicken eggs (n = 350 were randomly divided into the control group and the groups treated with nano-Au, HS, and nano-Au+HS. The experimental solutions were given in ovo on the first day of incubation and the embryos were evaluated on day 20 of incubation. The methods included biochemical indi- ces in blood, immunohistochemistry, microscopy (transmission electron microscopy, scanning electron microscopy, confocal, and gene expression at the messenger ribonucleic acid and protein levels.Results: The treatments did not adversely affect mortality, organ weight, and homeostasis of the embryos. HS stimulated the development and maturation of breast muscle by increasing the number of nuclei, satellite cells, and muscle fibers and affected the expression of basic fibroblast growth factor-2 and paired-box transcription factor-7. Furthermore, the nano-Au+HS complex contributed to the increased number of myocytes and nuclei in

  18. EFFECT OF GLUTAMATE MANGANESE ON THE REPRODUCTIVE FUNCTION AND EMBRYOGENESIS OF FEMALE RATS

    Directory of Open Access Journals (Sweden)

    Shtapenko O. V.

    2015-12-01

    Full Text Available Pregnancy is associated with increased nutritional needs due to the physiologic changes of the female and the metabolic demands of the embryo/fetus. The use of chelating compounds with high biological activity increased the fertility of female rats by stimulation metabolism and functional activity of the reproductive system. Manganese is an essential element utilized by antioxidants, including superoxide dismutase (MnSOD, and others metalloenzymes that take part in reduction reactions, in multiple physiological processes including reproductive system. The aim of the research was to determine the effect of subcutaneous injections of Mn glutamate in liposomal forms on the reproductive system and the process of embryogenesis of experimental female rat. The study was conducted on female rats aged 2.5-3 months with body weight of 180-200 g. Rats with dated gestation were divided into three groups: two experimental and control. Female rabbits of the 1th experimental group were subcutaneous injected of 2 mg/ml for Mn glutamate in liposomal form one week before fertilization and the animals of the 2th group were obtained the same preparation during fertilization. Rats were euthanized on the twentieth day, ovariens were singled out of fiber, visual inspection and counting the number of yellow bodies were performed, absolute and relative mass indexes were determined, Mn glutamate influence index was calculated. Experimental results showed that the administration of Mn glutamate 7 days before fertilization and during fertilization significant increased the number of corpora lutea of pregnancy (p<0,001, number of live fetuses (p<0,001 due to the decrease in general and pre-implantation embryonic mortality compared with the control group. The experimental results showed improvement in key indicators of embryonic development. We observed significant increase in the number of implanted embryos on 1 female at 10,7±0,26 and 11,3±0,21 (p<0,001 (9,4±0,16 vs

  19. Comparative analysis reveals dynamic changes in miRNAs and their targets and expression during somatic embryogenesis in longan (Dimocarpus longan Lour..

    Directory of Open Access Journals (Sweden)

    Yuling Lin

    Full Text Available Somatic embryogenesis (SE, which resembles zygotic embryogenesis, is an essential component of the process of plant cell differentiation and embryo development. Although microRNAs (miRNAs are important regulators of many plant develop- mental processes, their roles in SE have not been thoroughly investigated. In this study, we used deep-sequencing, computational, and qPCR methods to identify, profile, and describe conserved and novel miRNAs involved in longan (Dimocarpus longan SE. A total of 643 conserved and 29 novel miRNAs (including star strands from more than 169 miRNA families were identified in longan embryogenic tissue using Solexa sequencing. By combining computational and degradome sequencing approaches, we were able to predict 2063 targets of 272 miRNAs and verify 862 targets of 181 miRNAs. Target annotation revealed that the putative targets were involved in a broad variety of biological processes, including plant metabolism, signal transduction, and stimulus response. Analysis of stage- and tissue-specific expressions of 20 conserved and 4 novel miRNAs indicated their possible roles in longan SE. These miRNAs were dlo-miR156 family members and dlo-miR166c* associated with early embryonic culture developmental stages; dlo-miR26, dlo-miR160a, and families dlo-miR159, dlo-miR390, and dlo-miR398b related to heart-shaped and torpedo- shaped embryo formation; dlo-miR4a, dlo-miR24, dlo-miR167a, dlo-miR168a*, dlo-miR397a, dlo-miR398b.1, dlo-miR398b.2, dlo-miR808 and dlo-miR5077 involved in cotyledonary embryonic development; and dlo-miR17 and dlo-miR2089*-1 that have regulatory roles during longan SE. In addition, dlo-miR167a, dlo-miR808, and dlo-miR5077 may be required for mature embryo formation. This study is the first reported investigation of longan SE involving large-scale cloning, characterization, and expression profiling of miRNAs and their targets. The reported results contribute to our knowledge of somatic embryo miRNAs and

  20. Late Sovereign Diplomacy

    DEFF Research Database (Denmark)

    Adler-Nissen, Rebecca

    2009-01-01

    the promotion of national interests with those of the Union. In this late sovereign phase of diplomacy, political and legal authorities overlap, territorial exclusivity is replaced with functional boundaries, and states begin to speak with one voice. The article explores three interlinked aspects of late...... sovereign diplomacy: the teleological interpretation of the EC and EU treaties; the intense socialization of state representatives; and the negotiation process, which promotes national positions as part of a European cause, thereby delocalizing the national interest. While the EU has not rendered national...... diplomacy obsolete, it has profoundly changed its meaning and consequences....

  1. Early and late motherhood

    DEFF Research Database (Denmark)

    Christoffersen, Mogens; Lausten, Mette

    2009-01-01

    The study investigates parental child rearing methods, structural factors relating to the family during adolescence geographic segregation, individual resource deficits and social background of first time late live births among 32 to 37 years old women and compare to teenagers before becoming...... teenage mothers. The purpose is to study if results will be consistent with the hypotheses that poverty, social deprivation during adolescence and low education are causes of teen childbearing but also childlessness among elder women in the age group 32 to 37 years old. Could childlessness as well...... pregnant teenagers who had an induced abortion. Quite the opposite pattern is disclosed for late motherhood....

  2. Somatic embryogenesis and direct as well as indirect organogenesis in Lilium pumilum DC. Fisch., an endangered ornamental and medicinal plant.

    Science.gov (United States)

    Zhang, Jing; Gai, MeiZhu; Li, XueYan; Li, TianLai; Sun, HongMei

    2016-10-01

    Somatic embryogenesis and organogenesis in Lilium pumilum were successfully regulated by picloram, α-naphthaleneacetic acid (NAA), and 6-benzyladenine (BA). In organogenesis, the highest shoot regeneration frequency (92.5%) was obtained directly from bulb scales on Murashige and Skoog (MS) medium containing 2.0 mg L(-1) BA and 0.2 mg L(-1) NAA, while organogenic callus (OC) formed from leaves on MS medium supplemented with 1.0 mg L(-1) BA and 0.5 mg L(-1) NAA. Following subculture, 76.7% of OC regenerated shoots. In somatic embryogenesis, the combination of picloram and NAA increased the amount of embryogenic callus (EC) that formed with a maximum on 90.7% of all explants which formed 11 somatic embryos (SEs) per explant. Differences between EC and OC in cellular morphology and cell differentiation fate were easily observed. SEs initially formed via an exogenous or an endogenous origin. The appearance of a protoderm in heart-shaped SE and the bipolar shoot-root development in oval-shaped SE indicated true somatic embryogenesis. This protocol provides a new and detailed regulation and histological examination of regeneration pattern in L. pumilum.

  3. Embryogenesis of the histaminergic system in the pond snail, Lymnaea stagnalis L.: an immunocytochemical and biochemical study.

    Science.gov (United States)

    Hegedus, E; Kaslin, J; Elekes, K

    2004-01-01

    Embryogenesis of the histaminergic system in the pond snail, Lymnaea stagnalis, was investigated by means of immunocytochemistry and HPLC assay. From the earliest onset of the of histamine-immunoreactive (HA-IR) elements, the labelled neurons were confined to the pedal, cerebral and buccal ganglia, whereas no IR cells within the pleural, parietal and visceral ganglia were detectable during the embryogenesis. Peripheral projections of the embryonic HA-IR neurons were missing. No transient HA-IR neurons could be found either inside or outside the CNS. The first HA-IR elements appeared at about E55% of embryonic development, at the beginning of metamorphosis, and were represented by three pairs of neurons located in the cerebral ganglia. Following metamorphosis, four pairs of HA-IR neurons were added; two of them occurred in the pedal (E65% stage of development) and two in the buccal (E90% stage of development) ganglia. During embryogenesis, HA-IR fibers were present in the cerebro-pedal connectives and in the cerebral, pedal and buccal commissures, whereas only little arborization could be observed in the neuropil of the ganglia. HPLC measurements revealed a gradual increase of HA content in the embryos during development, corresponding well to the course of the appearance of immunolabeled elements. It is suggested that the developing HAergic system plays a specific role in the process of gangliogenesis and CNS plasticity of embryonic Lymnaea.

  4. Embryogenesis induction, callogenesis, and plant regeneration by in vitro culture of tomato isolated microspores and whole anthers.

    Science.gov (United States)

    Seguí-Simarro, José M; Nuez, Fernando

    2007-01-01

    In this work, some of the different in vitro developmental pathways into which tomato microspores or microsporocytes can be deviated experimentally were explored. The two principal ones are direct embryogenesis from isolated microspores and callus formation from meiocyte-containing anthers. By means of light and electron microscopy, the process of early embryogenesis from isolated microspores and the disruption of normal meiotic development and change of developmental fate towards callus proliferation, morphogenesis, and plant regeneration have been shown. From microspores isolated at the vacuolate stage, embryos can be directly induced, thus avoiding non-androgenic products. In contrast, several different morphogenic events can be triggered in cultures of microsporocyte-containing anthers under adequate conditions, including indirect embryogenesis, adventitious organogenesis, and plant regeneration. Both callus and regenerated plants may be haploid, diploid, and mostly mixoploid. The results demonstrate that both gametophytic and sporophytic calli occur in cultured tomato anthers, and point to an in vitro-induced disturbance of cytokinesis and subsequent fusion of daughter nuclei as a putative cause for mixoploidy and genome doubling during both tetrad compartmentalization and callus proliferation. The potential implications of the different alternative pathways are discussed in the context of their application to the production of doubled-haploid plants in tomato, which is still very poorly developed.

  5. Factors influencing cucumber (Cucumis sativus L. somatic embryogenesis. I. The crucial role of pH and nitrogen in suspension culture

    Directory of Open Access Journals (Sweden)

    Tadeusz Wróblewski

    2014-01-01

    Full Text Available A method of obtaining and the characteristics of an embryogenic stabilised cucumber (Cucumis sativus L. suspension culture which has many similarities to the carrot model are presented. The Specific Type I cells and proembryogenic mass were present in such a suspension. The maintenance of the proembryogenic stage took place in medium containing 2,4-D as the sole growth regulator, subsequent stages of embryogenesis occurred in hormone-free medium. Embryonic structures were also observed in medium with auxin in the late stages of growth, probably due to the depletion of 2,4-D in the medium during subculture. The choice of the proper inorganic nitrogen sources and the maintenance of correct proportions between them had a significant effect on the formation of these structures. We have shown that the pH of the medium with an embryogenic culture became stabilized regardless of the initial pH value and depended on the medium composition. The inoculum used for the initiation of subsequent subcultures of the stable suspension culture was 1 part tissue to 300 parts medium and was small in comparison to the systems described for the cucumber so far. From 1 ml of basic suspension 7 embryos were obtained on medium without growth regulators 10 days after inoculation, and this amount increased to 21 after 3 weeks. From 3.2% of the somatic embryos it was posible to regenerate plants. The high yield and synchronisation of the process and the development of embryos without passing through callus tissue create the possibility of using this system for molecular investigations and in the technology of somatic seed production.

  6. Identifying Activity

    CERN Document Server

    Lewis, Adrian S

    2009-01-01

    Identification of active constraints in constrained optimization is of interest from both practical and theoretical viewpoints, as it holds the promise of reducing an inequality-constrained problem to an equality-constrained problem, in a neighborhood of a solution. We study this issue in the more general setting of composite nonsmooth minimization, in which the objective is a composition of a smooth vector function c with a lower semicontinuous function h, typically nonsmooth but structured. In this setting, the graph of the generalized gradient of h can often be decomposed into a union (nondisjoint) of simpler subsets. "Identification" amounts to deciding which subsets of the graph are "active" in the criticality conditions at a given solution. We give conditions under which any convergent sequence of approximate critical points finitely identifies the activity. Prominent among these properties is a condition akin to the Mangasarian-Fromovitz constraint qualification, which ensures boundedness of the set of...

  7. Developmental biochemistry of cottonseed embryogenesis and germination. VII. Free amino acid pool composition during cotyledon development

    Energy Technology Data Exchange (ETDEWEB)

    Capdevila, A.M.; Dure, L. III

    1977-01-01

    The composition of the free amino acid pool in embryonic cotton (Gossypium hirsutum) cotyledons is quite distinct from that of endosperm, and that of germinated, greened cotyledons is quite distinct from that of leaves. During germination (including the precocious germination of immature seeds), the pool expands considerably showing a pronounced accumulation of asparagine. The high level of asparagine found in seedling roots and in the cotyledon vascular exudate indicates that this is the major transported amino acid in germination. There is no pool expansion in the presence of abscisic acid. In the presence of actinomycin D, the pool expands, but an enormous accumulation of glutamine takes place. The composition of the pool at any stage is not related to the composition of the isoacceptor transfer RNA pool, nor to the composition of the storage protein. Anaerobiosis leads to an accumulation of aspartate, alanine, and glycine at the expense of asparagine; however, desiccation does not result in an accumulation of proline. Conspicuously high levels of arginine are maintained through embryogenesis and germination. The levels of individual amino acids are presented as nanomol per cotyledon pair and as percent of total pool.

  8. Morphological and molecular development of the eyes during embryogenesis of the freshwater planarian Schmidtea polychroa.

    Science.gov (United States)

    Martín-Durán, José María; Monjo, Francisco; Romero, Rafael

    2012-03-01

    Photoreception is one of the most primitive sensory functions in metazoans. Despite the diversity of forms and components of metazoan eyes, many studies have demonstrated the existence of a common cellular and molecular basis for their development. Genes like pax6, sine oculis, eyes absent, dachshund, otx, Rx and atonal are known to be associated with the specification and development of the eyes. In planarians, sine oculis, eyes absent and otxA play an essential role during the formation of the eye after decapitation, whereas pax6, considered by many authors as a master control gene for eye formation, does not seem to be involved in adult eye regeneration. Whether this is a peculiarity of adult planarians or, on the contrary, is also found in embryogenesis remains unknown. Herein, we characterize embryonic eye development in the planarian species Schmidtea polychroa using histological sections and molecular markers. Additionally, we analyse the expression pattern of the pax6-sine oculis-eyes absent-dachshund network, and the genes Rx, otxA, otxB and atonal. We demonstrate that eye formation in planarian embryos shows great similarities to adult eye regeneration, both at the cellular and molecular level. We thus conclude that planarian eyes exhibit divergent molecular patterning mechanisms compared to the prototypic ancestral metazoan eye.

  9. p53 pathway is involved in cell competition during mouse embryogenesis.

    Science.gov (United States)

    Zhang, Guoxin; Xie, Yinyin; Zhou, Ying; Xiang, Cong; Chen, Lai; Zhang, Chenxi; Hou, Xiaoshuang; Chen, Jiong; Zong, Hui; Liu, Geng

    2017-01-17

    The function of tumor suppressor p53 has been under intense investigation. Acute stresses such as DNA damage are able to trigger a high level of p53 activity, leading to cell cycle arrest or apoptosis. In contrast, the cellular response of mild p53 activity induced by low-level stress in vivo remains largely unexplored. Murine double minute (MDM)2 and MDM4 are two major negative regulators of p53. Here, we used the strategy of haploinsufficiency of Mdm2 and Mdm4 to induce mild p53 activation in vivo and found that Mdm2(+/-)Mdm4(+/-) double-heterozygous mice exhibited normal embryogenesis. However, closer examination demonstrated that the Mdm2(+/-)Mdm4(+/-) cells exhibited a growth disadvantage and were outcompeted during development in genetic mosaic embryos that contained wild-type cells. Further study indicated the out-competition phenotype was dependent on the levels of p53. These observations revealed that cells with mild p53 activation were less fit and exhibited altered fates in a heterotypic environment, resembling the cell competition phenomenon first uncovered in Drosophila By marking unfit cells for elimination, p53 may exert its physiological role to ensure organ and animal fitness.

  10. The E3 ubiquitin ligase activity of Trip12 is essential for mouse embryogenesis.

    Directory of Open Access Journals (Sweden)

    Masashi Kajiro

    Full Text Available Protein ubiquitination is a post-translational protein modification that regulates many biological conditions. Trip12 is a HECT-type E3 ubiquitin ligase that ubiquitinates ARF and APP-BP1. However, the significance of Trip12 in vivo is largely unknown. Here we show that the ubiquitin ligase activity of Trip12 is indispensable for mouse embryogenesis. A homozygous mutation in Trip12 (Trip12(mt/mt that disrupts the ubiquitin ligase activity resulted in embryonic lethality in the middle stage of development. Trip12(mt/mt embryos exhibited growth arrest and increased expression of the negative cell cycle regulator p16. In contrast, Trip12(mt/mt ES cells were viable. They had decreased proliferation, but maintained both the undifferentiated state and the ability to differentiate. Trip12(mt/mt ES cells had increased levels of the BAF57 protein (a component of the SWI/SNF chromatin remodeling complex and altered gene expression patterns. These data suggest that Trip12 is involved in global gene expression and plays an important role in mouse development.

  11. Immunization with L. sigmodontis microfilariae reduces peripheral microfilaraemia after challenge infection by inhibition of filarial embryogenesis.

    Directory of Open Access Journals (Sweden)

    Sebastian Ziewer

    Full Text Available BACKGROUND: Lymphatic filariasis and onchocerciasis are two chronic diseases mediated by parasitic filarial worms causing long term disability and massive socioeconomic problems. Filariae are transmitted by blood-feeding mosquitoes that take up the first stage larvae from an infected host and deliver it after maturation into infective stage to a new host. After closure of vector control programs, disease control relies mainly on mass drug administration with drugs that are primarily effective against first stage larvae and require many years of annual/biannual administration. Therefore, there is an urgent need for alternative treatment ways, i.e. other effective drugs or vaccines. METHODOLOGY/PRINCIPAL FINDINGS: Using the Litomosoides sigmodontis murine model of filariasis we demonstrate that immunization with microfilariae together with the adjuvant alum prevents mice from developing high microfilaraemia after challenge infection. Immunization achieved 70% to 100% protection in the peripheral blood and in the pleural space and furthermore strongly reduced the microfilarial load in mice that remained microfilaraemic. Protection was associated with the impairment of intrauterine filarial embryogenesis and with local and systemic microfilarial-specific host IgG, as well as IFN-γ secretion by host cells from the site of infection. Furthermore immunization significantly reduced adult worm burden. CONCLUSIONS/SIGNIFICANCE: Our results present a tool to understand the immunological basis of vaccine induced protection in order to develop a microfilariae-based vaccine that reduces adult worm burden and prevents microfilaraemia, a powerful weapon to stop transmission of filariasis.

  12. Effect of picloram, additives and plant growth regulators on somatic embryogenesis of Phyla nodiflora (L. Greene

    Directory of Open Access Journals (Sweden)

    Abdul Bakrudeen Ali Ahmed

    2011-02-01

    Full Text Available The present study describes the plant regeneration via somatic embryogenesis in suspension culture derived from the leaf and stem explants of Phyla nodiflora. The medium type, plant growth regulators, complex extract (coconut milk and malt extract and anti-oxidant (activated charcoal, ascorbic acid, Polyvinylpyrrolidone and citric acid markedly influenced the embryo regeneration of P. nodiflora. MS with 2,4-D and activated charcoal (10 mg/L gave the highest stimulation of embryogenic callus growth. Optimized callus was transfered into suspension culture, which showed the globular, heart shaped embryos in MS with 2,4-D + BA + picloram (0.1 mg/L, coconut milk (10 ml/L, citric acid (100 mg/L on 6th subcultures. Further development stages such as torpedo and cotyledonary stage embryos and fostered maturation of embryos were observed at 8th and 10th subculture. However, the high frequency embryo germination and plantlet (45 plants/20 mg cotyledonary stages embryos formation was obtained in half-strength MS medium without growth regulators from cotyledonary embryos. All the plantlets established in the field exhibited morphological characters similar to those of the mother plant.

  13. Micropropagation of Codiaeum variegatum (L.) Blume and regeneration induction via adventitious buds and somatic embryogenesis.

    Science.gov (United States)

    Radice, Silvia

    2010-01-01

    Codiaeum variegatum (L) Blume cv. "Corazon de oro" and cv. "Norma" are successfully micropropagated when culture are initiated with explants taken from newly sprouted shoots. The establishment and multiplication steps are possible when 1 mg/L BA or 1 mg/L IAA and 3 mg/L 2iP are added to MS medium, according to the cultivar respectively selected.Adventive organogenesis and somatic embryogenesis are induced from leaf explants taken from in vitro buds of croton. On leaf-sectioned of "Corazon de oro" cultured in vitro, 1 mg/L BA stimulates continuous somatic embryos development and induces some shoots too. Replacing BA with 1 mg/L TDZ induces up to 100% bud regeneration in the same explants. On the other hand, leaf-sectioned of C. variegatum cv. Norma does not start somatic embryo differentiation if 1 mg/L TDZ is not added to the MS basal medium. Incipient callus is observed after 30 days of culture, and then, subculture to MS with 1 mg/L BA allows the same process to show on the "Corazon de oro" cultivar. Somatic embryos show growth arrest that is partially overcome by transfer to hormone-free basal medium with activated charcoal. Root induction is possible on basal medium plus 1 mg/L IBA. Plantlets in the greenhouse have variegated leaves true-to-type.

  14. Light sheet-based imaging and analysis of early embryogenesis in the fruit fly.

    Science.gov (United States)

    Khairy, Khaled; Lemon, William C; Amat, Fernando; Keller, Philipp J

    2015-01-01

    The fruit fly is an excellent model system for investigating the sequence of epithelial tissue invaginations constituting the process of gastrulation. By combining recent advancements in light sheet fluorescence microscopy (LSFM) and image processing, the three-dimensional fly embryo morphology and relevant gene expression patterns can be accurately recorded throughout the entire process of embryogenesis. LSFM provides exceptionally high imaging speed, high signal-to-noise ratio, low level of photoinduced damage, and good optical penetration depth. This powerful combination of capabilities makes LSFM particularly suitable for live imaging of the fly embryo.The resulting high-information-content image data are subsequently processed to obtain the outlines of cells and cell nuclei, as well as the geometry of the whole embryo tissue by image segmentation. Furthermore, morphodynamics information is extracted by computationally tracking objects in the image. Towards that goal we describe the successful implementation of a fast fitting strategy of Gaussian mixture models.The data obtained by image processing is well-suited for hypothesis testing of the detailed biomechanics of the gastrulating embryo. Typically this involves constructing computational mechanics models that consist of an objective function providing an estimate of strain energy for a given morphological configuration of the tissue, and a numerical minimization mechanism of this energy, achieved by varying morphological parameters.In this chapter, we provide an overview of in vivo imaging of fruit fly embryos using LSFM, computational tools suitable for processing the resulting images, and examples of computational biomechanical simulations of fly embryo gastrulation.

  15. Mouse cofactor of BRCA1 (Cobra1 is required for early embryogenesis.

    Directory of Open Access Journals (Sweden)

    Asma Amleh

    Full Text Available BACKGROUND: Negative elongation factor (NELF is a four-subunit protein complex conserved from Drosophila to humans. In vitro biochemical and tissue culture-based studies have demonstrated an important role of NELF in controlling RNA polymerase II (Pol II pausing in transcription. However, the physiological significance of NELF function is not clear due to the lack of any genetic systems for studying NELF. PRINCIPAL FINDINGS: Here we show that disruption of the mouse B subunit of NELF (NELF-B, also known as cofactor of BRCA1 (Cobra1, causes inner cell mass (ICM deficiency and embryonic lethality at the time of implantation. Consistent with the phenotype of the Cobra1 knockout (KO embryos, knockdown of Cobra1 in mouse embryonic stem cells (ESCs reduces the efficiency of colony formation and increases spontaneous differentiation. Cobra1-depleted ESCs maintain normal levels of Oct4, Nanog, and Sox2, master regulators of pluripotency in ESCs. However, knockdown of Cobra1 leads to precocious expression of developmental regulators including lymphoid enhancer-binding factor 1 (Lef1. Chromatin immunoprecipitation (ChIP indicates that Cobra1 binds to the Lef1 promoter and modulates the abundance of promoter-bound RNA polymerase. CONCLUSIONS: Cobra1 is essential for early embryogenesis. Our findings also indicate that Cobra1 helps maintain the undifferentiated state of mESCs by preventing unscheduled expression of developmental genes.

  16. Effects of gravity on meiosis, fertilization and early embryogenesis in Caenorhabditis elegans

    Science.gov (United States)

    Sasagawa, Y.; Saito, Y.; Shimizu, M.; Ishioka, N.; Yamashita, M.; Takahashi, H.; Higashitani, A.

    The embryonic development of the nematode Caenorhabditis elegans was examined under different gravitational conditions. The first cleavage plane in the 1-cell embryo was slid to some extent by re-orientation of liquid culture vessel, but the pattern and timing of cleavages were not affected. Under 100G of hypergravity condition with swing-centrifuge, the number of eggs laid from an adult hermaphrodite decreased and their hatching rate was drastically reduced. On the other hand, the embryonic development after fertilization normally occurred and grew to adulthood at more than 100G of hypergravity. When the adult hermaphrodites cultured under 100G of hypergravity transferred to a ground condition (1G), the newly fertilized embryos normally developed and their hatching rate was fully recovered. These results indicated that the reproductive process except spermatogenesis, oogenesis and embryogenesis after fertilization is impaired under 100G of hypergravity condition, and the effect is transient. Namely, the fertilization process including meiotic divisions I and II is sensitive to hypergravity in the nematode C. elegans.

  17. Conifer somatic embryogenesis: improvements by supplementation of medium with oxidation-reduction agents.

    Science.gov (United States)

    Pullman, Gerald S; Zeng, Xiaoyan; Copeland-Kamp, Brandi; Crockett, Jonathan; Lucrezi, Jacob; May, Sheldon W; Bucalo, Kylie

    2015-02-01

    A major barrier to the commercialization of somatic embryogenesis technology in loblolly pine (Pinus taeda L.) is recalcitrance of some high-value crosses to initiate embryogenic tissue (ET) and continue early-stage somatic embryo growth. Developing initiation and multiplication media that resemble the seed environment has been shown to decrease this recalcitrance. Glutathione (GSH), glutathione disulfide (GSSG), ascorbic acid and dehydroascorbate analyses were performed weekly throughout the sequence of seed development for female gametophyte and zygotic embryo tissues to determine physiological concentrations. Major differences in stage-specific oxidation-reduction (redox) agents were observed. A simple bioassay was used to evaluate potential growth-promotion of natural and inorganic redox agents added to early-stage somatic embryo growth medium. Compounds showing statistically significant increases in early-stage embryo growth were then tested for the ability to increase initiation of loblolly pine. Low-cost reducing agents sodium dithionite and sodium thiosulfate increased ET initiation for loblolly pine and Douglas fir (Mirb) Franco. Germination medium supplementation with GSSG increased somatic embryo germination. Early-stage somatic embryos grown on medium with or without sodium thiosulfate did not differ in GSH or GSSG content, suggesting that sodium thiosulfate-mediated growth stimulation does not involve GSH or GSSG. We have developed information demonstrating that alteration of the redox environment in vitro can improve ET initiation, early-stage embryo development and somatic embryo germination in loblolly pine.

  18. Somatic Embryogenesis and Plant Regeneration from Two Recalcitrant Genotypes of Gossypium hirsutum L.

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-xia; WANG Xing-fen; MA Zhi-ying; ZHANG Gui-yin; HAN Gai-ying

    2006-01-01

    An improved protocol has been developed for somatic embryogenesis and plant regeneration of recalcitrant cotton cultivars. High callus frequencies and embryogenic tissue were developed in MSB medium supplemented with gradient concentrations of KT and 2,4-D, their concentration decreasing from 0.1 to 0.01 mg L-1. Somatic embryos were successfully incubated in 1/2 macronutrient MSB suspension supplemented with 0.5 g L-1 glutamine and 0.5 g L-1 asparagine. Decrease in macronutrient concentration of MSB significantly alleviated browning and was beneficial to suspension cells.Transformation of somatic embryos into plants was induced in MSB medium supplemented with 3% sucrose, 0.5 g L-1 glutamine, 0.5 g L-1 asparagine, and 6.0 g L-1 agar. The effect of sucrose as carbohydrate was better than that of glucose for plant germination. Using this protocol, regenerated plantlets from the CCRI521 and Zhongzhi86-6 reached to as much as 19.6 and 18.5% somatic embryos, respectively.

  19. The α-tocopherol transfer protein is essential for vertebrate embryogenesis.

    Directory of Open Access Journals (Sweden)

    Galen W Miller

    Full Text Available The hepatic α-tocopherol transfer protein (TTP is required for optimal α-tocopherol bioavailability in humans; mutations in the human TTPA gene result in the heritable disorder ataxia with vitamin E deficiency (AVED, OMIM #277460. TTP is also expressed in mammalian uterine and placental cells and in the human embryonic yolk-sac, underscoring TTP's significance during fetal development. TTP and vitamin E are essential for productive pregnancy in rodents, but their precise physiological role in embryogenesis is unknown. We hypothesize that TTP is required to regulate delivery of α-tocopherol to critical target sites in the developing embryo. We tested to find if TTP is essential for proper vertebrate development, utilizing the zebrafish as a non-placental model. We verify that TTP is expressed in the adult zebrafish and its amino acid sequence is homologous to the human ortholog. We show that embryonic transcription of TTP mRNA increases >7-fold during the first 24 hours following fertilization. In situ hybridization demonstrates that Ttpa transcripts are localized in the developing brain, eyes and tail bud at 1-day post fertilization. Inhibiting TTP expression using oligonucleotide morpholinos results in severe malformations of the head and eyes in nearly all morpholino-injected embryos (88% compared with 5.6% in those injected with control morpholinos or 1.7% in non-injected embryos. We conclude that TTP is essential for early development of the vertebrate central nervous system.

  20. [Early Stages of Skull Embryogenesis in the Grass Snake, Natrix natrix (Serpentes, Colubridae)].

    Science.gov (United States)

    Kovtun, M F; Sheverdyukova, H V

    2015-01-01

    Studies of previous authors on snake skull embryogenesis have been performed on embryos obtained from eggs after oviposition. The aim of this study was to investigate the initial stages of chondrocranium development in Grass-snake Natrixnatrix Linnaeus, 1758, embryos before oviposition. Natrix natrix embryos at early developmental stages (24-27 according to the table of normal development by D. Zehr (1962)) were obtained by means of caesarean section. At developmental stages 25-27, previously undescribed structures were found in the region of future skull formation. These structures exist during one or two stages and then disappear. Therefore, we call them "temporary structures." The assumption about the nature of these structures is based on their topography and comparison with the structures of developing or fully formed chondrocranium in other vertebrates. It is hypothesized that the temporary structures in Natrix natrix chondrocranium are vestiges ofprimary chondrocranium of ancestral vertebrate forms, and they indicate the existence of several variants in the formation of chondrocranium in the historical vertebrates.' development.

  1. Transgenic peanut plants obtained by particle bombardment via somatic embryogenesis regeneration system

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    After pre-culture and treatment of osmosis,cotyledons of immature peanut(Arachis hypogaea L.)zygotic embryos were transformed via particle bombardment with a plasmid containing a chimeric hph gene conferring resistance to hygromycin and a chimeric intron-gus gene.Selection for hygromycin resistant calluses and somatic embryos was initiated at 10th d post-bombardment on medium containing 10-25 mg/L hygromycin.Under continuous selection,hygromycin resistant plantlets were regenerated from somatic embryos and were recovered from nearly 1.6% of the bombarded cotyledons.The presence and integration of foreign DNA in regenerated hygromycin resistant plants was confirmed by PCR(polymerase chain reaction)for the intron-gus gene and by Southern hybridization of the hph gene.GUS enzyme activity was detected in leaflets from transgenic plants but not from control,non-transformed plants.The production of transgenic plants are mainly based on a newly improved somatic embryogenesis regeneration system developed by us.

  2. A cell-based computational model of early embryogenesis coupling mechanical behaviour and gene regulation

    Science.gov (United States)

    Delile, Julien; Herrmann, Matthieu; Peyriéras, Nadine; Doursat, René

    2017-01-01

    The study of multicellular development is grounded in two complementary domains: cell biomechanics, which examines how physical forces shape the embryo, and genetic regulation and molecular signalling, which concern how cells determine their states and behaviours. Integrating both sides into a unified framework is crucial to fully understand the self-organized dynamics of morphogenesis. Here we introduce MecaGen, an integrative modelling platform enabling the hypothesis-driven simulation of these dual processes via the coupling between mechanical and chemical variables. Our approach relies upon a minimal ‘cell behaviour ontology' comprising mesenchymal and epithelial cells and their associated behaviours. MecaGen enables the specification and control of complex collective movements in 3D space through a biologically relevant gene regulatory network and parameter space exploration. Three case studies investigating pattern formation, epithelial differentiation and tissue tectonics in zebrafish early embryogenesis, the latter with quantitative comparison to live imaging data, demonstrate the validity and usefulness of our framework. PMID:28112150

  3. Embryogenesis of the Uropygial Glands in the Laysan Albatross (Phoebastria immutabilis (Rothschild, 1893): Procellariiformes).

    Science.gov (United States)

    Rehorek, S J; Wu, J L; Smith, T D; Beeching, S C

    2017-08-01

    An avian uropygial gland is located on the mid-dorsum of the tail, and is the only external gland found in birds. Most studies have focused on the function, gross anatomy and chemical nature of this gland, with little research on its ontogeny. The purpose of this study was to examine the development of this gland in a series of Laysan Albatross (Phoebastria immutabilis) embryos. Specimens were examined anatomically and histologically. It was found that grooves preceded glandular development by many stages. The embryogenesis of the uropygial gland was divided into 6 phases: preinception, groove inception, mesodermal separation, migrating mesodermal cells, oval shaped "depressions", constriction and finally glandular inception. No other gland is known to develop similarly, though there may be parallels with femoral gland development. In comparison to other bird species, the length of the development period in the Albatross, as well as other compounding factors, make it difficult to determine the significance of these observations. The development of a mesodermal band, soon to be a connective tissue capsule, is more complex than originally described in ducks. Thus, the unique nature of this gland is established, but the significance of the observations required further studies into uropygial gland development. Anat Rec, 300:1420-1428, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  4. Lethality in PARP-1/Ku80 double mutant mice reveals physiologicalsynergy during early embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Henrie, Melinda S.; Kurimasa, Akihiro; Burma, Sandeep; Menissier-de Murcia, Josiane; de Murcia, Gilbert; Li, Gloria C.; Chen,David J.

    2002-09-24

    Ku is an abundant heterodimeric nuclear protein, consisting of 70-kDa and 86-kDa tightly associated subunits that comprise the DNA binding component of DNA-dependent protein kinase. Poly(ADP)ribose polymerase-1 (PARP-1) is a 113-kDa protein that catalyzes the synthesis of poly(ADP-ribose) on target proteins. Both Ku and PARP-1 recognize and bind to DNA ends. Ku functions in the non-homologous end joining (NHEJ) repair pathway whereas PARP-1 functions in the single strand break repair and base excision repair (BER) pathways. Recent studies have revealed that PARP-1 and Ku80 interact in vitro. To determine whether the association of PARP-1 and Ku80 has any physiological significance or synergistic function in vivo, mice lacking both PARP-1 and Ku80 were generated. The resulting offspring died during embryonic development displaying abnormalities around the gastrulation stage. In addition, PARP-1-/-Ku80-/- cultured blastocysts had an increased level of apoptosis. These data suggest that the functions of both Ku80 and PARP-1 are essential for normal embryogenesis and that a loss of genomic integrity leading to cell death through apoptosis is likely the cause of the embryonic lethality observed in these mice.

  5. Evaluation of Somatic Embryogenesis Ability in Robusta Coffee (Coffea canephora Pierre

    Directory of Open Access Journals (Sweden)

    Priyono Priyono

    2010-08-01

    Full Text Available Embriogenesis somatik diharapkan sebagai metode perbanyakan tanaman yang sangat efektif pada kopi. Evaluasi dua jenis proses embriogenesis somatik, yaitu proses langsung dan tidak langsung akan bermanfaat untuk menggambarkan kemampuan proliferasi sel. Penelitian untuk mengevaluasi embriogenesis somatik kopi Robusta (Coffea canephora yang mempunyai tingkat keragaman genetik tinggi telah dilakukan di Nestlé R&D Centre Tours, Perancis. Bahan tanam menggunakan kopi Robusta koleksi Nestle Perancis dan tiga klon koleksi Pusat Penelitian Kopi dan Kakao Indonesia (Puslitkoka. Tiga aspek, yaitu proses embriogenesis, keragaman embriogenesis dan kemantapan embriogenesis dievaluasi dalam penelitian ini. Hasil penelitian menunjukkan bahwa baik embriogenesis somatik langsung maupun tidak langsung dapat diamati. Penelitian ini menunjukkan bahwa kedua proses embriogenesis somatik tersebut merupakan dua mekanisme yang berbeda. Dalam penelitian ini ditunjukkan bahwa kemampuan embriognesis somatik tergantung pada genotipe, baik antar maupun di dalam kelompok genetik kopi Robusta, yaitu Congolese,Guinean dan Conillon. Lebih lanjut diketahui bahwa kedua proses embriogenesis somatik tersebut stabil terhadap indukan sebagai sumber eksplan. Kemampuan embriogenesis somatik tidak langsung ketiga klon Puslitkoka (BP409, BP961 dan Q121 sangat beragam, sehingga memberikan harapan adanya pola segregasi yang baik berdasarkan kemampuan embriogenesis somatik tidak langsung pada populasi yang dibuat dari silangan klon tersebut.Key words: Coffea canephora, somatic embryogenesis, variability, stability, genotype.

  6. THE GROWTH PERFORMANCE OF CITRUS DERIVED FROM SOMATIC EMBRYOGENESIS PLANTLET AND SCION STOCK

    Directory of Open Access Journals (Sweden)

    Nirmala Friyanti Devy

    2014-10-01

    Full Text Available Somatic embryogenesis (SE of callus culture in vitro is one of citrus propagation ways for producing free virus and genetically true-to-type plantlets. To induce growing of plantlets derived from this technology, they should be grafted ex vitro onto a citrus rootstock. The research aimed to evaluate the growth performance of citrus plants cv. Siam Kintamani (Citrus nobilis L. that used both plantlets and scions as their stocks. The research was conducted at Tlekung Research Station, Indonesian Citrus and Subtropical Fruit Research Institute from June 2011 to December 2012. The treatments were done at nursery house by grafting a plantlet and budding a scion onto an eight-month-old Japanese Citroon (JC rootstock plant. The grafted and budded plants of one-year old were maintained at nursery house then transplanted into the field. In the field, the research was arranged in a randomized block design with three replications and used 15 plants as unit samples. The results showed that the vegetative growth of Siam Kintamani seedling derived from SE or grafted plant was faster than that of budded plant started from 10 to 12 months after treatment in the nersery house. In the field, the growth of SE grafted plant was only significantly different up to 6 months after transplanting. Plantlets produced from SE in vitro propagation can be used as a good alternative stock material for producing healthy citrus plants. Therefore, a further research is required especially on varieties used, reproductive growth and massive planlets production.

  7. Somatic embryogenesis and histological analysis from zygotic embryos in Vitis vinifera L. 'Moldova'

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    We examined the somatic embryogenesis from and histological studies of zygotic embryos of seeds in European Grape 'Moldova' (Vitis vinifera L. 'Moldova'). Primary calli were initiated on Nitsch and Nitsch (NN) medium supplemented with 1.0mg'L-1 2,4-D and 0.5 mg'L-1 6-BA. Embryogenic calli were produced upon transfer to a NN medium with 0.5 mg-L-1 6-BA and 2 mg.L-1 NAA and somatic embryos were obtained on a half strength MS medium without plant growth regulators. During the somatic embryo germination, an addition of 1.0 mg.L-1 6-BA in the medium could accelerate somatic embryos to develop into normal plants and increase the conversion rate from 0 to 43.3%. Histological studies of embryogenic calli and somatic embryos demonstrated dy-namic changes of proteins and starch grains. The developmental processes of somatic embryos were similar to those of zygotic em-bryos, including typical epiderma, cotyledon primordium and vascular tissue.

  8. Involvement of Toll-like receptor 4 in the embryogenesis of the rodent filaria Litomosoides sigmodontis.

    Science.gov (United States)

    Pfarr, Kenneth M; Fischer, Kerstin; Hoerauf, Achim

    2003-02-01

    To examine the role that lipopolysaccharide (LPS)-like molecules from the filarial intracellular endobacteria Wolbachia might play in the development of filarial infections, a natural infection in the LPS-nonresponsive C3H/HeJ mouse strain was compared to that of the LPS-responsive C3H/HeN mouse strain. C3H/HeN mice have been shown to be susceptible to the rodent filarial nematode Litomosoides sigmodontis, with the development of adult worms including females containing mature microfilariae (first stage larvae) in the uterine tubes. However, free microfilariae are not detected. In this study the worm burden and worm length were not significantly different between the C3H/HeN and C3H/HeJ mice. However, the fertility of worms from CeH/HeJ mice was found to be higher than those from C3H/HeN mice. Significantly, mature microfilariae were found at the site of infection only in C3H/HeJ mice. These results indicate a role for TLR4 signaling in the immune response that inhibits worm embryogenesis and prevents the release of microfilariae or directly kills released microfilariae.

  9. [Effect of bacterial endotoxin on migration of gonadotropin-releasing, hormone producing neurons in rat embryogenesis].

    Science.gov (United States)

    Sharova, V S; Izvol'skaia, M S; Voronova, S N; Zakharova, L A

    2011-01-01

    The effect of bacterial lipopolysaccharide endotoxin (LPS), immune system activator, on differentiation and migration of gonadotropin-releasing, hormone producing neurons in rat embryogenesis has been studied. Intraperitoneal introduction of LPS (18 jg/kg) to pregnant rats on the 12th day of pregnancy led to 50% decrease in total number of GRH-neurons in the forebrain of 17-day-old embryos and 17% decrease in 19-day-old embryos. At the same time, the number of GRH-neurons in the nasal area of the head of 17- and 19-day-old embryos increased by 40 and 50%, respectively, whereas it increased by 20% in olfactory bulbs of 17-day-old embryos and did not changed in olfactory bulbs of 19-day-old embryos. Neither the total number of neurons nor their distribution patterns were affected by the introduction of LPS into pregnant rats on the 15th day of pregnancy. Singular localization of GRH-neurons in embryo forebrain was observed after LPS administration, whereas the neurons were located by groups of 3-4 cells in rostral areas. Therefore, at the early stages of pregnancy, LPS was shown to suppress initial stages of differentiation and migration of GRH producing neurons. The effects observed in our study may be mediated by LPS-induced, proinflammatory cytokines.

  10. Stress induced acquisition of somatic embryogenesis in common bean Phaseolus vulgaris L.

    Science.gov (United States)

    Cabrera-Ponce, José Luis; López, Liliana; León-Ramírez, Claudia G; Jofre-Garfias, Alba E; Verver-y-Vargas, Aurora

    2015-03-01

    Common bean Phaseolus vulgaris L. has been shown to be a recalcitrant plant to induce somatic embryogenesis (SE) under in vitro conditions. We used an alternative strategy to induce SE in common bean based upon the use of a cytokinin (BAP) coupled with osmotic stress adaptation instead of SE response that is induced by auxins. Explants derived from zygotic embryos of common bean were subjected to osmotic stress (sucrose 12 % w/v, 0.5 M) in the presence of BAP 10 mg/L and adenine free base 40 mg/L to induce somatic embryos from specific competent cells of the apical meristem and cotyledonary node. Somatic embryos were obtained from the competent cells in a direct response (direct SE). In a secondary response (secondary SE), those somatic embryos formed proembryogenic masses (PEM) that originated/developed into secondary somatic embryos and showed the SE ontogeny. Maturation of somatic embryos was achieved by using different osmolality media and converted to plants. Full-visible light spectrum was necessary to achieve efficient plant regeneration. Long-term recurrent SE was demonstrated by propagation of PEM at early stages of SE. This protocol is currently being applied for stable genetic transformation by means of Agrobacterium tumefaciens and bioballistics as well as for basic biochemical and molecular biology experiments.

  11. Expression of hunchback during oogenesis and embryogenesis in Locusta migratoria manilensis (Meyen).

    Science.gov (United States)

    He, ZhengBo; Cao, YueQing; Chen, Bin; Li, TingJing

    2011-02-01

    hb (hunchback) is a contributing factor in anteroposterior axial patterning of insects. Although the hb function in Locusta migratoria manilensis has been investigated, its expression pattern remains unknown. Here, the mouse polyclonal antibody was produced against Hb fusion protein, and then its expression pattern during oogenesis and embryogenesis of L. migratoria manilensis was examined by immunohistochemical staining. Hb protein was detected in the oocyte nucleus which was positioned centrally within the developing oocyte. The oocyte nucleus gradually moved to the posterior end of the egg along with the oocyte maturing. In freshly laid eggs, Hb formed gradient at the posterior end of the egg, and then hb was expressed as a band in the middle of the blastodisc. As the blastodisc differentiated into the head and trunk, the expression region became wide, which would develop into spatial gnathal and thoracic segments. With abdominal segmentation, the expression domain in the gnathal and thoracic region became faint and eventually faded out, while the Hb expression domain appeared at the posterior growth zone in a discontinuous expression manner. The hb expression pattern of L. migratoria manilensis is greatly similar to that of other locusts, such as Schistocerca americana and another L. migratoria. Compared with other insects, hb expression is conserved in the gnathal and thoracic domains, while divergent in oogenesis and abdomen.

  12. Characterization, cDNA cloning and expression pattern of relaxin gene during embryogenesis of Danio rerio.

    Science.gov (United States)

    Fiengo, Marcella; Donizetti, Aldo; del Gaudio, Rosanna; Minucci, Sergio; Aniello, Francesco

    2012-06-01

    We report the identification, the cDNA cloning, the temporal and spatial expression pattern analysis of the rln gene in the zebrafish Danio rerio. The deduced Rln B and A domains show different evolutionary conservation. Rln B domain shows higher similarity when compared to zebrafish and human RLN3 B domain than human RLN1 and RLN2 B domain. Differently, the zebrafish Rln A domain shows relatively low amino acid sequence similarity when compared with the same sequences. The rln gene is transcribed both during embryogenesis and in adult organism, where higher transcript level has been particularly evidenced in the brain. Moreover, we provide the first description of rln spatial expression pattern during embryonic development. In particular, we show restricted transcript localization starting at the pharyngula stage in olfactory placode, branchial arch region, and in a cell cluster near to otic vesicle. In larval stage, new transcription territories have been detected in both neural and non-neural regions. In particular, in the brain, rln expression has been revealed in telencephalic region around anterior commissure, in the preoptic area, and in restricted rombencephalic cell clusters. Expression of rln gene in extra-neural territories has been detected in the pancreatic and thyroid gland regions. Danio rerio rln expression pattern analysis reveals shared features with the mammalian RLN gene, particularly in the brain, where it might have a role in the neurophysiological processes. In addition, expression in the thyroid and pancreas region suggests a function as a paracrine and endocrine hormone.

  13. Loss of competence for glyoxysome formation during somatic embryogenesis in anise (Pimpinella anisum L.) suspension cultures.

    Science.gov (United States)

    Kudielka, R A; Theimer, R R

    1983-10-01

    Somatic embryogenesis in anise (Pimpinella anisum L.) suspension cultures induced by transfer to hormone-free growth medium may be synchronized by previous selection of cell aggregates with diameters between 100-240 μm. Around 80-90% of the embryoids are globular after 2-3 d, heart-shaped after 5-7 d and torpedo-shaped after 9 d. In embryogenic medium without source of carbon or with 20 mmol/l acetate differentiation and growth cease. But like in dedifferentiated cell aggregates the key enzyme activities for glyoxysomes such as isocitrate lyase and malate synthase are induced in globular (3 d old) and heart-shaped (5 d old) embryoids, but not in embryoids at day 7 or later. Similarly, in explants from anise hypocotyl glyoxysomes cannot be derepressed by such treatment. It is concluded that during differentiation of heart-shaped embryoids to torpedo forms the competence of the cells for the yet unknown inducing principle for glyoxysomes is lost.

  14. IMPROVED PLANT REGENERATION AND IN VITRO SOMATIC EMBRYOGENESIS IN Ruta graveolens

    Directory of Open Access Journals (Sweden)

    Zuraida AR

    2014-07-01

    Full Text Available In vitro callus cultures initiated from stem segments of Ruta graveolen which later on differentiated into somatic embryoids and subsequently regenerated whole plants. Callus formation was observed in culture medium containing low concentrations of the plant growth regulators, 2,4-dichlorophenoxyacetic acid (2,4-D and/or α-naphthalene acetic acid (NAA. At 0.2 mg/L NAA was showing the highest rate (85% of callus induction. The callus appeared watery, but showed no sign of browning after a month of culture. Sub-culturing the callus on to medium with 0.2 mg/L 2,4-D showed enhanced the callus proliferation rate up to 95%. Somatic embryogenesis from callus was most successful on MS medium containing either 6 g/L agar and supplemented with 0.5 mg/L benzylaminopurine (BAP, or with 9 g/L agar, supplemented with 0.5 mg/L kinetin (KIN. The former medium was more successful in plantlet regeneration when the embryoids were subsequently transferred to regeneration medium with 3 g/L agar and 0.5 mg/L BAP.

  15. Loss of col8a1a function during zebrafish embryogenesis results in congenital vertebral malformations.

    Science.gov (United States)

    Gray, Ryan S; Wilm, Thomas P; Smith, Jeff; Bagnat, Michel; Dale, Rodney M; Topczewski, Jacek; Johnson, Stephen L; Solnica-Krezel, Lilianna

    2014-02-01

    Congenital vertebral malformations (CVM) occur in 1 in 1000 live births and in many cases can cause spinal deformities, such as scoliosis, and result in disability and distress of affected individuals. Many severe forms of the disease, such as spondylocostal dystostosis, are recessive monogenic traits affecting somitogenesis, however the etiologies of the majority of CVM cases remain undetermined. Here we demonstrate that morphological defects of the notochord in zebrafish can generate congenital-type spine defects. We characterize three recessive zebrafish leviathan/col8a1a mutant alleles ((m531, vu41, vu105)) that disrupt collagen type VIII alpha1a (col8a1a), and cause folding of the embryonic notochord and consequently adult vertebral column malformations. Furthermore, we provide evidence that a transient loss of col8a1a function or inhibition of Lysyl oxidases with drugs during embryogenesis was sufficient to generate vertebral fusions and scoliosis in the adult spine. Using periodic imaging of individual zebrafish, we correlate focal notochord defects of the embryo with vertebral malformations (VM) in the adult. Finally, we show that bends and kinks in the notochord can lead to aberrant apposition of osteoblasts normally confined to well-segmented areas of the developing vertebral bodies. Our results afford a novel mechanism for the formation of VM, independent of defects of somitogenesis, resulting from aberrant bone deposition at regions of misshapen notochord tissue.

  16. Never Too Late

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A historical issue is being raised on Capitol Hill.In late May,members of the U.S.Congress introduced bipartisan resolutions in both chambers,calling on the federal legislature to acknowledge formally and express regret for discriminatory legislation and how the country accordingly treated Chinese immigrants more than a century ago.

  17. Big Java late objects

    CERN Document Server

    Horstmann, Cay S

    2012-01-01

    Big Java: Late Objects is a comprehensive introduction to Java and computer programming, which focuses on the principles of programming, software engineering, and effective learning. It is designed for a two-semester first course in programming for computer science students.

  18. Was I Late

    Institute of Scientific and Technical Information of China (English)

    叶历来; 罗琪芳

    2011-01-01

    “Get up, Jane!” “Oh... Mom, let me sleep five more minutes. I'm so Ured ( 困的 ).” “It's 7:50. It's too late. ” “OK, three minutes then... Wait! What did you say? What time is it? It's 7:50.”

  19. Kisspeptins modulate the biology of multiple populations of gonadotropin-releasing hormone neurons during embryogenesis and adulthood in zebrafish (Danio rerio.

    Directory of Open Access Journals (Sweden)

    Yali Zhao

    Full Text Available Kisspeptin1 (product of the Kiss1 gene is the key neuropeptide that gates puberty and maintains fertility by regulating the gonadotropin-releasing hormone (GnRH neuronal system in mammals. Inactivating mutations in Kiss1 and the kisspeptin receptor (GPR54/Kiss1r are associated with pubertal failure and infertility. Kiss2, a paralogous gene for kiss1, has been recently identified in several vertebrates including zebrafish. Using our transgenic zebrafish model system in which the GnRH3 promoter drives expression of emerald green fluorescent protein, we investigated the effects of kisspeptins on development of the GnRH neuronal system during embryogenesis and on electrical activity during adulthood. Quantitative PCR showed detectable levels of kiss1 and kiss2 mRNA by 1 day post fertilization, increasing throughout embryonic and larval development. Early treatment with Kiss1 or Kiss2 showed that both kisspeptins stimulated proliferation of trigeminal GnRH3 neurons located in the peripheral nervous system. However, only Kiss1, but not Kiss2, stimulated proliferation of terminal nerve and hypothalamic populations of GnRH3 neurons in the central nervous system. Immunohistochemical analysis of synaptic vesicle protein 2 suggested that Kiss1, but not Kiss2, increased synaptic contacts on the cell body and along the terminal nerve-GnRH3 neuronal processes during embryogenesis. In intact brain of adult zebrafish, whole-cell patch clamp recordings of GnRH3 neurons from the preoptic area and hypothalamus revealed opposite effects of Kiss1 and Kiss2 on spontaneous action potential firing frequency and membrane potential. Kiss1 increased spike frequency and depolarized membrane potential, whereas Kiss2 suppressed spike frequency and hyperpolarized membrane potential. We conclude that in zebrafish, Kiss1 is the primary stimulator of GnRH3 neuronal development in the embryo and an activator of stimulating hypophysiotropic neuron activities in the adult, while

  20. Timelines in the insect brain: fates of identified neural stem cells generating the central complex in the grasshopper Schistocerca gregaria.

    Science.gov (United States)

    Boyan, George; Liu, Yu

    2014-02-01

    This study employs labels for cell proliferation and cell death, as well as classical histology to examine the fates of all eight neural stem cells (neuroblasts) whose progeny generate the central complex of the grasshopper brain during embryogenesis. These neuroblasts delaminate from the neuroectoderm between 25 and 30 % of embryogenesis and form a linear array running from ventral (neuroblasts Z, Y, X, and W) to dorsal (neuroblasts 1-2, 1-3, 1-4, and 1-5) along the medial border of each protocerebral hemisphere. Their stereotypic location within the array, characteristic size, and nuclear morphologies, identify these neuroblasts up to about 70 % of embryogenesis after which cell shrinkage and shape changes render progressively more cells histologically unrecognizable. Molecular labels show all neuroblasts in the array are proliferative up to 70 % of embryogenesis, but subsequently first the more ventral cells (72-75 %), and then the dorsal ones (77-80 %), cease proliferation. By contrast, neuroblasts elsewhere in the brain and optic lobe remain proliferative. Apoptosis markers label the more ventral neuroblasts first (70-72 %), then the dorsal cells (77 %), and the absence of any labeling thereafter confirms that central complex neuroblasts have exited the cell cycle via programmed cell death. Our data reveal appearance, proliferation, and cell death proceeding as successive waves from ventral to dorsal along the array of neuroblasts. The resulting timelines offer a temporal blueprint for building the neuroarchitecture of the various modules of the central complex.

  1. LEAFY COTYLEDON1-CASEIN KINASE I-TCP15-PHYTOCHROME INTERACTING FACTOR4 Network Regulates Somatic Embryogenesis by Regulating Auxin Homeostasis1[OPEN

    Science.gov (United States)

    Min, Ling; Hu, Qin; Li, Yaoyao; Xu, Jiao; Ma, Yizan; Zhu, Longfu; Yang, Xiyan; Zhang, Xianlong

    2015-01-01

    Somatic embryogenesis (SE) is an efficient tool for the propagation of plant species and also, a useful model for studying the regulatory networks in embryo development. However, the regulatory networks underlying the transition from nonembryogenic callus to somatic embryos during SE remain poorly understood. Here, we describe an upland cotton (Gossypium hirsutum) CASEIN KINASE I gene, GhCKI, which is a unique key regulatory factor that strongly affects SE. Overexpressing GhCKI halted the formation of embryoids and plant regeneration because of a block in the transition from nonembryogenic callus to somatic embryos. In contrast, defective GhCKI in plants facilitated SE. To better understand the mechanism by which GhCKI regulates SE, the regulatory network was analyzed. A direct upstream negative regulator protein, cotton LEAFY COTYLEDON1, was identified to be targeted to a cis-element, CTTTTC, in the promoter of GhCKI. Moreover, GhCKI interacted with and phosphorylated cotton CINCINNATA-like TEOSINTE BRANCHED1-CYCLOIDEA-PCF transcription factor15 by coordinately regulating the expression of cotton PHYTOCHROME INTERACTING FACTOR4, finally disrupting auxin homeostasis, which led to increased cell proliferation and aborted somatic embryo formation in GhCKI-overexpressing somatic cells. Our results show a complex process of SE that is negatively regulated by GhCKI through a complex regulatory network. PMID:26491146

  2. LEAFY COTYLEDON1-CASEIN KINASE I-TCP15-PHYTOCHROME INTERACTING FACTOR4 Network Regulates Somatic Embryogenesis by Regulating Auxin Homeostasis.

    Science.gov (United States)

    Min, Ling; Hu, Qin; Li, Yaoyao; Xu, Jiao; Ma, Yizan; Zhu, Longfu; Yang, Xiyan; Zhang, Xianlong

    2015-12-01

    Somatic embryogenesis (SE) is an efficient tool for the propagation of plant species and also, a useful model for studying the regulatory networks in embryo development. However, the regulatory networks underlying the transition from nonembryogenic callus to somatic embryos during SE remain poorly understood. Here, we describe an upland cotton (Gossypium hirsutum) CASEIN KINASE I gene, GhCKI, which is a unique key regulatory factor that strongly affects SE. Overexpressing GhCKI halted the formation of embryoids and plant regeneration because of a block in the transition from nonembryogenic callus to somatic embryos. In contrast, defective GhCKI in plants facilitated SE. To better understand the mechanism by which GhCKI regulates SE, the regulatory network was analyzed. A direct upstream negative regulator protein, cotton LEAFY COTYLEDON1, was identified to be targeted to a cis-element, CTTTTC, in the promoter of GhCKI. Moreover, GhCKI interacted with and phosphorylated cotton CINCINNATA-like TEOSINTE BRANCHED1-CYCLOIDEA-PCF transcription factor15 by coordinately regulating the expression of cotton PHYTOCHROME INTERACTING FACTOR4, finally disrupting auxin homeostasis, which led to increased cell proliferation and aborted somatic embryo formation in GhCKI-overexpressing somatic cells. Our results show a complex process of SE that is negatively regulated by GhCKI through a complex regulatory network.

  3. In vitro somatic embryogenesis and plantlet regeneration from immature male inflorescence of adult dura and tenera palms of Elaeis guineensis (Jacq.).

    Science.gov (United States)

    Jayanthi, Madhavan; Susanthi, Bollarapu; Murali Mohan, Nandiganti; Mandal, Pranab Kumar

    2015-01-01

    We report here a method for plant regeneration through somatic embryogenesis from explants collected from immature male inflorescence of adult oil palm cultivated in India. Callus induction was successful from tissues of immature male inflorescence collected from both dura and tenera varieties of oil palm. A modified Y3 (Eeuwens) media supplemented with several additives and activated charcoal (3%) were used for the experiments. Out of four different auxin treatments, 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) produced maximum callus induction (82%) and it was not significantly different from 2,4-dichlorophenoxyacetic acid (2,4-D) and a combination of 2,4-D + picloram. The callus induction obtained with auxin α-naphthalene acetic acid was only 54% and it was significantly low as compared to the other treatments. Highest embryogenesis was obtained with a combination of 2,4-D + picloram (4.9%) followed by picloram (3.4%). Genotypic variation in response to the same auxins was observed both for callus induction and embryogenesis. Callus induction and embryogenesis ranged from 42 to 72% and 6.8 to 9.35%, respectively in tenera. The formation of embryogenic calli was marked by the appearance of white to yellowish globular or nodular structures which subsequently formed clear somatic embryos. Somatic embryogenesis was asynchronous and at one time we could find different stages of embryogenesis like the globular, torpedo and the cotyledonary stages. The somatic embryos when exposed to light in the same basal media along with 6-benzyladenine (18 µM), abscisic acid (3.78 µM) and gibberellic acid (5.78 µM) regenerated into plantlets. To the best of our knowledge this is the first report o f callus induction and somatic embryogenesis from immature male inflorescence of oil palm.

  4. Late Babylonian Astrology

    Science.gov (United States)

    Steele, John M.

    The last five centuries BC saw the development of several new forms of astrology in Babylonia. Key to these new astrological techniques was the invention of the zodiac in about 400 BC. These new forms of astrology include personal horoscopes, astral medicine, and the exploitation of geometrical relationships between the position of heavenly bodies. Several Late Babylonian astrological doctrines were later adopted within Greek astrology.

  5. Zebrafish phenotypic screen identifies novel Notch antagonists.

    Science.gov (United States)

    Velaithan, Vithya; Okuda, Kazuhide Shaun; Ng, Mei Fong; Samat, Norazwana; Leong, Sze Wei; Faudzi, Siti Munirah Mohd; Abas, Faridah; Shaari, Khozirah; Cheong, Sok Ching; Tan, Pei Jean; Patel, Vyomesh

    2017-04-01

    Zebrafish represents a powerful in vivo model for phenotype-based drug discovery to identify clinically relevant small molecules. By utilizing this model, we evaluated natural product derived compounds that could potentially modulate Notch signaling that is important in both zebrafish embryogenesis and pathogenic in human cancers. A total of 234 compounds were screened using zebrafish embryos and 3 were identified to be conferring phenotypic alterations similar to embryos treated with known Notch inhibitors. Subsequent secondary screens using HEK293T cells overexpressing truncated Notch1 (HEK293TΔE) identified 2 compounds, EDD3 and 3H4MB, to be potential Notch antagonists. Both compounds reduced protein expression of NOTCH1, Notch intracellular domain (NICD) and hairy and enhancer of split-1 (HES1) in HEK293TΔE and downregulated Notch target genes. Importantly, EDD3 treatment of human oral cancer cell lines demonstrated reduction of Notch target proteins and genes. EDD3 also inhibited proliferation and induced G0/G1 cell cycle arrest of ORL-150 cells through inducing p27(KIP1). Our data demonstrates the utility of the zebrafish phenotypic screen and identifying EDD3 as a promising Notch antagonist for further development as a novel therapeutic agent.

  6. Three-dimensional computer modeling of birds proepicardium on different stages of embryogenesis

    Directory of Open Access Journals (Sweden)

    Pototskaya O.Yu.

    2009-01-01

    Full Text Available As the proepicardium is the source of many cell populations of the mature heart, including cell components of coronary vessels, its investigation became actual last time. It is known, that there are some differences between birds and mammalian proepicardium; one of them consists in the way, in which they contact to myocardium: mammalian proepicardium produce vesicles, which contact to atrioventricular groove, wile in birds there is no vesicles and whole protrusions of proepicardium attach to the heart. But, recent years it became evident, that in rat proepicardium there are no vesicles during all stages of its existence, and in birds there is a proepicardium-like structure producing vesicles, which attach to the heart. Thus, the goal of our research was to characterize changes in the shape of proepicardium during bird’s embryogenesis. We used Cobb 500 chick embryos as a material; on the basis of pictures of proepicardium serial sections, with the help of Photoshop CS2, Amira for microscopy 5.0, 3ds max 8.0 computer programs, we made three-dimensional models of proepicardium on 15, 16, 17, 18, 21 stages of development by V.Hamburger, H.Hamilton, 1951. The most important changes in proepicardium shape observed from 14 to 20 stages of development. During this period proepicardium appeared on the right horn of sinus venous, enlarged and formed several crests, which contacted to atrioventricular groove. Coalescence of these crests led to dorsal mesocardium formation. From 21 to 27 stages of development there were no significant changes in proepicardium shape; the area of its contact to sinus venous was grown downwards while the area of contact to the heart enlarged. No vesicles, no “finger-like protrusions” were observed on any stage of bird’s development.

  7. Effects of breeder hen age and dietary L-carnitine on progeny embryogenesis.

    Science.gov (United States)

    Peebles, E D; Kidd, M T; McDaniel, C D; Tanksley, J P; Parker, H M; Corzo, A; Woodworth, J C

    2007-06-01

    1. Ross 308 broiler breeder hens were given diets containing 0 or 25 mg L-carnitine/kg (8 replications per treatment) from 21 weeks of age. 2. Hens were inseminated with semen from Ross broiler breeder males. In a common facility, subsequent progeny hatchability and embryonic mortality at 25, 30, 32, and 38 weeks of breeder age were evaluated. 3. Subsequent egg component weights, incubational egg water loss, progeny embryo growth, and embryo, yolk sac and liver composition through 18 d of incubation at 27, 32, and 38 weeks of breeder age were evaluated. 4. Calculated additions of L-carnitine were in agreement with analysed contents of 3.5 and 31.1 mg free L-carnitine/kg of diet, respectively, and total L-carnitine concentrations increased by 48.6, 21.7, and 10.0% in 0-d yolk, 18-d yolk sac, and 18-d liver samples, respectively, due to the addition of dietary L-carnitine. 5. Supplemental L-carnitine resulted in increased (0.6%) relative 0-d egg yolk weight across weeks 27, 32, and 38, and reduced (0.38%) 18-d yolk sac palmitoleic acid concentration at week 27 without altering embryogenesis. 6. In conclusion, dietary L-carnitine (25 mg/kg of the diet) was deposited in the yolks of broiler breeder hens and was subsequently transferred to the embryonic liver via yolk sac absorption through 18 d of incubation. Furthermore, dietary L-carnitine supplementation increased ovarian follicle yolk deposition in 27-, 32-, and 38-week-old breeder hens, and influenced yolk sac fatty acid beta-oxidation in embryos from 27-week-old breeder hens causing yolk sac palmitoleic acid concentrations to be reduced by 18 d of incubation.

  8. Drosophila MOF controls Checkpoint protein2 and regulates genomic stability during early embryogenesis

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    Pushpavalli Sreerangam NCVL

    2013-01-01

    Full Text Available Abstract Background In Drosophila embryos, checkpoints maintain genome stability by delaying cell cycle progression that allows time for damage repair or to complete DNA synthesis. Drosophila MOF, a member of MYST histone acetyl transferase is an essential component of male X hyperactivation process. Until recently its involvement in G2/M cell cycle arrest and defects in ionizing radiation induced DNA damage pathways was not well established. Results Drosophila MOF is highly expressed during early embryogenesis. In the present study we show that haplo-insufficiency of maternal MOF leads to spontaneous mitotic defects like mitotic asynchrony, mitotic catastrophe and chromatid bridges in the syncytial embryos. Such abnormal nuclei are eliminated and digested in the yolk tissues by nuclear fall out mechanism. MOF negatively regulates Drosophila checkpoint kinase 2 tumor suppressor homologue. In response to DNA damage the checkpoint gene Chk2 (Drosophila mnk is activated in the mof mutants, there by causing centrosomal inactivation suggesting its role in response to genotoxic stress. A drastic decrease in the fall out nuclei in the syncytial embryos derived from mof1/+; mnkp6/+ females further confirms the role of DNA damage response gene Chk2 to ensure the removal of abnormal nuclei from the embryonic precursor pool and maintain genome stability. The fact that mof mutants undergo DNA damage has been further elucidated by the increased number of single and double stranded DNA breaks. Conclusion mof mutants exhibited genomic instability as evidenced by the occurance of frequent mitotic bridges in anaphase, asynchronous nuclear divisions, disruption of cytoskeleton, inactivation of centrosomes finally leading to DNA damage. Our findings are consistent to what has been reported earlier in mammals that; reduced levels of MOF resulted in increased genomic instability while total loss resulted in lethality. The study can be further extended using

  9. Drosophila MOF controls Checkpoint protein2 and regulates genomic stability during early embryogenesis.

    Science.gov (United States)

    Pushpavalli, Sreerangam N C V L; Sarkar, Arpita; Ramaiah, M Janaki; Chowdhury, Debabani Roy; Bhadra, Utpal; Pal-Bhadra, Manika

    2013-01-24

    In Drosophila embryos, checkpoints maintain genome stability by delaying cell cycle progression that allows time for damage repair or to complete DNA synthesis. Drosophila MOF, a member of MYST histone acetyl transferase is an essential component of male X hyperactivation process. Until recently its involvement in G2/M cell cycle arrest and defects in ionizing radiation induced DNA damage pathways was not well established. Drosophila MOF is highly expressed during early embryogenesis. In the present study we show that haplo-insufficiency of maternal MOF leads to spontaneous mitotic defects like mitotic asynchrony, mitotic catastrophe and chromatid bridges in the syncytial embryos. Such abnormal nuclei are eliminated and digested in the yolk tissues by nuclear fall out mechanism. MOF negatively regulates Drosophila checkpoint kinase 2 tumor suppressor homologue. In response to DNA damage the checkpoint gene Chk2 (Drosophila mnk) is activated in the mof mutants, there by causing centrosomal inactivation suggesting its role in response to genotoxic stress. A drastic decrease in the fall out nuclei in the syncytial embryos derived from mof¹/+; mnkp⁶/+ females further confirms the role of DNA damage response gene Chk2 to ensure the removal of abnormal nuclei from the embryonic precursor pool and maintain genome stability. The fact that mof mutants undergo DNA damage has been further elucidated by the increased number of single and double stranded DNA breaks. mof mutants exhibited genomic instability as evidenced by the occurance of frequent mitotic bridges in anaphase, asynchronous nuclear divisions, disruption of cytoskeleton, inactivation of centrosomes finally leading to DNA damage. Our findings are consistent to what has been reported earlier in mammals that; reduced levels of MOF resulted in increased genomic instability while total loss resulted in lethality. The study can be further extended using Drosophila as model system and carry out the interaction of MOF

  10. Genetic transformation via somatic embryogenesis to establish herbicide-resistant opium poppy.

    Science.gov (United States)

    Facchini, Peter J; Loukanina, Natalia; Blanche, Vincent

    2008-04-01

    A reliable genetic transformation protocol via somatic embryogenesis has been developed for the production of fertile, herbicide-resistant opium poppy plants. Transformation was mediated by Agrobacterium tumefaciens using the pCAMBIA3301 vector, which harbors the phosphinothricin acetyltransferase (pat) gene driven by a tandem repeat of the cauliflower mosaic virus (CaMV) 35S promoter and the beta-glucuronidase (gus) structural gene driven by a single copy of the CaMV 35S promoter between left- and right-border sequences. Co-cultivation of explants and A. tumefaciens was performed in the presence of 50 microM ATP and 50 microM MgCl(2). Root explants pre-cultured on callus induction medium were used for transformation. Herbicide-resistant, proliferating callus was obtained from explants on a medium containing both 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-benzyladenine (BA). Globular embryogenic callus, induced by removal of the BA from the medium, was placed on a hormone-free medium to form somatic embryos, which were converted to plantlets under specific culture conditions. Plantlets with roots were transferred to soil, allowed to mature and set seed. Both pat and gus gene transcripts, and PAT and GUS enzyme activities were detected in the transgenic lines tested. Histochemical localization of GUS activity in T(1) opium poppy plants revealed transgene expression in most tissues of all plant organs. The protocol required 8-12 months to establish transgenic T(1) seed stocks and was developed using a commercial opium poppy cultivar that produces high levels of pharmaceutical alkaloids.

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

    Science.gov (United States)

    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.

  12. IN VITRO REGENERATION OF THREE CHRYSANTHEMUM (Dendrathema grandiflora VARIETIES “VIA” ORGANOGENESIS AND SOMATIC EMBRYOGENESIS

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    Elizabeth Hodson de Jaramillo

    2008-09-01

    Full Text Available Chrysanthemum (Dendrathema grandiflora has a high demand in the Colombian and international cut flower markets.Since commercial production of this ornamental species is strongly affected by fungal diseases such as chrysanthemumwhite rust (Puccinia horiana, high doses of fungicides are being used posing increased environmental and commercialcosts. Assessment of in vitro regeneration systems from leaf discs was a first step in developing a plant genetic transformationprotocol to obtain fungi-resistant plants. Leaf discs of White Albatross, Yellow Albatross, and Escapade varieties wereestablished in vitro on MS medium supplemented with NAA (0 - 4.83 μM and BAP (0 - 13.32 μM alone and incombination. Leaf discs were also cultured on MumB medium containing 2,4-D (0 - 4.52 μM for 7, 14, and 21 days priorto their transferral to a 2,4-D free MumB medium. Regenerated shoots were individualized, rooted, and hardened. Resultsshow that MS with 4.83 μM NAA + 4.44 μM BAP and 4.83 μM NAA + 13.32 μM BAP induce organogenesis, and MumBwith 2.26 μM 2,4-D induces somatic embryogenesis on all three varieties, with exposition periods to 2,4-D of 14 days forWhite Albatross and 21 days for Yellow Albatross and Escapade. Shoot development from somatic embryos was observedin the three varieties when cultured on a 2,4-D free MumB medium. Spontaneous rooting was recorded in 85% of the shootsthus facilitating hardening and successful transfer to soil.

  13. The effects of ancymidol, abscisic acid, uniconazole and paclobutrazol on somatic embryogenesis of asparagus.

    Science.gov (United States)

    Li, B; Wolyn, D J

    1995-05-01

    The effects of ancymidol, abscisic acid (ABA), uniconazole, and paclobutrazol on asparagus somatic embryogenesis were evaluated. Calli induced from seedlings of genotype G447 were transferred to embryo induction medium (MS plus 3% sucrose, 0.1 mg L(-1) NAA, 0.5 mg L(-1) kinetin and 3% gelrite), with different concentrations of these compounds. After 8 weeks, the recovered bipolar or globular embryos were placed on germination medium (MS plus 6% sucrose, 0.1 mg L(-1) NAA, 0.1 mg L(-1) kinetin, 0.75 mg L(-1) ancymidol, 40 mg L(-1) adenine sulphate dihydrate, 0.17 mg L(-1) sodium phosphate monobasic and 3% gelrite) for conversion to plantlets. Inclusion of ancymidol, ABA, uniconazole and paclobutrazol in the embryo induction medium did not affect the total number of somatic embryos produced relative to the control without these compounds. However, ancymidol, ABA and uniconazole significantly improved embryo development by increasing the production of bipolar embryos 250-750% and decreasing that of globular embryos 8-35% relative to the control. The bipolar embryos produced with any of the four compounds in the embryo induction medium converted to plantlets at rates 700-1100% greater than the control. None of the globular embryos converted to plantlets. Ancymidol (0.75 mg L(-1)) and ABA (0.05 mg L(-1)) were the most effective treatments; 61 and 46 bipolar embryos g(-1) callus were produced, and 38% and 37% of the bipolar embryos converted to plantlets, respectively. These results indicated that ancymidol, ABA, uniconazole and paclobutrazol significantly enhanced the production of asparagus somatic embryos and their conversion to plantlets, and ancymidol and ABA were more effective than uniconazole and paclobutrazol.

  14. Xyloglucan Endotransglycosylase Activity in Carrot Cell Suspensions during cell Elongation and Somatic Embryogenesis.

    Science.gov (United States)

    Hetherington, P. R.; Fry, S. C.

    1993-11-01

    Xyloglucan endotransglycosylase (XET) has been proposed to contribute to cell elongation through wall loosening. To explore this relationship further, we assayed this enzyme activity in suspensions of carrot (Daucus carota L.) cells exhibiting various rates of cell elongation. In one cell line, elongation was induced by dilution into dichlorophenoxyacetic acid (2,4-D)-free medium. During this elongation, 93% of the XET activity was found in the culture medium; in nonelongating controls, by contrast, 68% was found in the cell extracts even though the specific activity of these extracts was lower than in the elongating cells. By far the highest rates of XET secretion per cell were in the elongating cells. A second cell line was induced to undergo somatic embryogenesis by dilution into 2,4-D-free medium. During the first 6 d, numerous globular embryoids composed of small, isodiametric cells were formed in the absence of cell elongation; extracellular XET activity was almost undetectable, and intracellular specific activity markedly declined. After 6 d, heart, torpedo, and cotyledonary embryoids began to appear (i.e. cell elongation resumed); the intracellular specific activity of XET rose rapidly and >80% of the XET activity accumulated in the medium. Thus, nonexpanding cell suspensions (whether or not they were rapidly dividing) produced and secreted less XET activity than did expanding cells. We propose that a XET molecule has an ephemeral wall-loosening role while it passes through the load-bearing layer of the wall on its way from the protoplast into the culture medium.

  15. Plant regeneration from protoplasts of immature Vigna sinensis cotyledons via somatic embryogenesis.

    Science.gov (United States)

    Li, X B; Xu, Z H; Wei, Z M

    1995-12-01

    Protoplasts were isolated from immature cotyledons of Vigna sinensis and cultured in a modified MS Liquid medium containing 0. 2 mg/l 2, 4-dichlorophenoxyacetic acid (2, 4-D), 1 mg/l naphthaleneacetic acid (NAA) and 0. 5 mg/l 6-benzylaminopurine (BAP) in the dark at a density of 1 × 10(5)/ml. The protoplasts began to divide in 3-5 days. Sustained cell division resulted in formation of cell clusters and small calli, with the cell division frequency and plating efficiency of cell colonies reaching 27. 7% and 1. 7% respectively. When calli of 2 mm in size were transferred onto MSB medium (MS salts and B5 vitamins) containing 500mg/l NaCl, 500 mg/ 1 casein hydrolysate (CH), 2 mg/l 2,4-D and 0. 5 mg/l BAP for further growth, approximately 5% of the calli developed embryogenically. The embryogenic calli were selected and subcultured on the same composition of MSB medium and were able to maintain somatic embryogenesis capacity in subculture for a long time. When the calli were moved to MSB medium with 0. 1 mg/l indole-3-acetic acid (IAA), 0. 5mg/l kinetin(KT), 3-5% mannitol and 2% sucrose in the light, many somatic embryos formed from the calli. Only part of the embryoids developed further to the cotyledonary stage, and the others died at the globular, heart-shaped or torpedo stages. Finally, some cotyledonary embryoids germinated and developed into plants or shoots. The shoots were readily rooted on 1/2 strength MS medium with 0. 1-0.3 mg/l indole-3-butyric acid (IBA). The plants grew well in soil and were fertile.

  16. Pragmatic Functions of Toddlers Who Are Late Talkers

    Science.gov (United States)

    MacRoy-Higgins, Michelle; Kaufman, Ilana

    2012-01-01

    Toddlers who are "late talkers" demonstrate reduced expressive vocabulary in the absence of physical, social, cognitive, or sensory impairment; they are usually identified at age 2, when they produce fewer than 50 words and do not combine words (Rescorla, 1989). This study analyzed spontaneous language samples of 10 late talking toddlers and 11…

  17. Morphology and Syntax in Late Talkers at Age 5

    Science.gov (United States)

    Rescorla, Leslie; Turner, Hannah L.

    2015-01-01

    Purpose: This study reports age 5 morphology and syntax skills in late talkers identified at age 2 (n = 34) and typically developing comparison children (n = 20). Results: The late talkers manifested significant morphological delays at ages 3 and 4 relative to comparison peers. Based on the 14 morphemes analyzed at age 5, the only significant…

  18. Coping – Late Side Effects

    Science.gov (United States)

    Cancer treatment can cause late side effects that may not show up for months or years after treatment. These late effects may include heart and lung problems, bone loss, eye and hearing changes, lymphedema, and other problems

  19. Late onset hereditary episodic ataxia.

    Science.gov (United States)

    Damak, M; Riant, F; Boukobza, M; Tournier-Lasserve, E; Bousser, M-G; Vahedi, K

    2009-05-01

    Episodic ataxias (EA) are hereditary paroxysmal neurological diseases with considerable clinical and genetic heterogeneity. So far seven loci have been reported and four different genes have been identified. Analysis of additional sporadic or familial cases is needed to better delineate the clinical and genetic spectrum of EA. A two generation French family with late onset episodic ataxia was examined. All consenting family members had a brain MRI with volumetric analysis of the cerebellum. Haplotype analysis was performed for the EA2 locus (19p13), the EA5 locus (2q22), the EA6 locus (5p13) and the EA7 locus (19q13). Mutation screening was performed for all exons of CACNA1A (EA2), EAAT1 (EA6) and the coding sequence of KCNA1 (EA1). Four family members had episodic ataxia with onset between 48 and 56 years of age but with heterogeneity in the severity and duration of symptoms. The two most severely affected had daily attacks of EA with a slowly progressive and disabling permanent cerebellar ataxia and a poor response to acetazolamide. Brain MRI showed in three affected members a decrease in the ratio of cerebellar volume:total intracranial volume, indicating cerebellar atrophy. No deleterious mutation was found in CACNA1A, SCA6, EAAT1 or KCNA1. In addition, the EA5 locus was excluded. A new phenotype of episodic ataxia has been described, characterised clinically by a late onset and progressive permanent cerebellar signs, and genetically by exclusion of the genes so far identified in EA.

  20. Recurrent somatic embryogenesis in long-term cultures of Gentiana lutea L. as a source for synthetic seed production for medium-term preservation

    Directory of Open Access Journals (Sweden)

    Holobiuc Irina

    2012-01-01

    Full Text Available Our aim was to establish an efficient and reproducible system for producing synthetic seeds from recurrent somatic embryogenesis in long-term cultures of Gentiana lutea L. This species is a vulnerable medicinal plant, protected both at the national and international levels, and is included in different Red Lists and Books. In vitro culture, as an alternative to classical methods of preservation, allows for the cyclic multiplication of plant material and short-, medium- and long-term preservation of tissue collections. Biotechnological approaches allow for maintenance of the plant material in a confined space and protection against biotic and abiotic factors. Somatic embryogenesis (SE is the most efficient way to regenerate plants, ensuring material for preservation and fundamental research. In our experiment, recurrent somatic embryogenesis was developed in long-term cultures in the presence of sugar alcohols (mannitol, sorbitol and in the absence of growth factors. This process proceeded at a high rate, with adventive somatic embryos being generated in a continuous process, followed by maturation, germination and development into plants. To follow the somatic embryogenesis process, histological samples were made. We used these embryogenic cultures for synthetic seed production and medium-term conservation. The viability of somatic embryos after moderate osmotic stress treatment was tested using TTC. Our methodology relied on the induction of somatic embryogenesis in the presence of auxins in the first cycle of in vitro cultures, long-term high embryogenic culture maintenance in the presence of sugar alcohols and synthetic seed production.

  1. Doubled haploid production from Spanish onion (Allium cepa L. germplasm: embryogenesis induction, plant regeneration and chromosome doubling

    Directory of Open Access Journals (Sweden)

    Oreto eFayos

    2015-05-01

    Full Text Available The use of doubled haploids in onion breeding is limited due to the low gynogenesis efficiency of this species. Gynogenesis capacity from Spanish germplasm, including the sweet cultivar Fuentes de Ebro, the highly pungent landrace BGHZ1354 and the two Valenciana type commercial varieties Recas and Rita, was evaluated and optimized in this study. The OH-1 population, characterized by a high gynogenesis induction, was used as control. Growing conditions of the donor plants were tested with a one-step protocol and field plants produced a slightly higher percentage of embryogenesis induction than growth chamber plants. A one-step protocol was compared with a two-step protocol for embryogenesis induction. Spanish germplasm produced a 2 to 3 times higher percentage of embryogenesis with the two-step protocol, Recas showing the highest percentage (2.09% and Fuentes de Ebro the lowest (0.53%. These percentages were significantly lower than those from the OH-1 population, with an average of 15% independently of the protocol used. The effect of different containers on plant regeneration was tested using both protocols. The highest percentage of acclimated plants was obtained with the two-step protocol in combination with Eco2box (70%, whereas the lowest percentage was observed with glass tubes in the two protocols (20-23%. Different amiprofos-methyl (APM treatments were applied to embryos for chromosome doubling. A similar number of doubled haploid plants were recovered with 25 or 50 µM APM in liquid medium. However, the application of 25 µM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 4 regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their

  2. Confirmation of Transgenic Robusta Coffee (Coffea canephora Transformed by Chitinase-encoding Gene and Its Propagation Through Somatic Embryogenesis

    Directory of Open Access Journals (Sweden)

    Priyono .

    2005-08-01

    Full Text Available Genetic engineering of Robusta coffee resistant to fungal diseases might be done by introducing a chitinase-encoding gene into genome of this plant. This research was aimed to confirm transgenic plant of BP 308 clone Robusta coffee transformed by chi gene and to evaluate its ability for the somatic embryogenesis. Confirmation of transgenic was carried out by analysis the presence of NPTII gene as a selectable marker for Canamysin resistant using PCR technique. The somatic embryo initiation and reproduction were evaluated in 11 plant accessions. Three kinds of sucrose concentration, 20%, 30% and 40% were applied in initiation stage of somatic embryo germination. The suitability of 4 medium, namely M1 (without addition by liquid medium, M2 (addition by liquid medium contained 0.25 mg/l kinetin, M3 (addition by liquid medium contained 0.25 mg/l IAA and M4 (addition by liquid medium contained 0.25 mg/l GA3 was evaluated for somatic embryo maturation. The result showed that 8 out of 10 plant accessions tested were transgenic and they could be propagated through somatic embryogenesis. The ability of transgenic plant for somatic embryo initiation, reproduction and regeneration were similar with that of nontransgenic one. Germination of somatic embryo could be improved by using 40% sucrose. Maturation of somatic embryo could be improved by addition of fresh liquid medium on the ancient gelled medium that used for somatic embryos reproduction. The best result was obtained on addition of fresh medium contained 0.25 mg/l GA 3 in which 65% of the somatic embryos developed to pre-germinate somatic embryo. Key words: Coffea canephora, transgenic plant, somatic embryogenesis.

  3. Influences of DMP on the fertilization process and subsequent embryogenesis of abalone (Haliotis diversicolor supertexta by gametes exposure.

    Directory of Open Access Journals (Sweden)

    Jin Zhou

    Full Text Available Di-methyl phthalate (DMP, a typical endocrine disrupting chemical (EDC, is ubiquitously distributed in aquatic environments; yet studies regarding its impact on gametes and the resulting effects on embryogenesis in marine gastropods are relatively scarce. In this study, the influences of DMP on the gametes and subsequent developmental process of abalone (Haliotis diversicolor supertexta, a representative marine benthic gastropod were assessed. Newborn abalone eggs and sperm were exposed separately to different DMP concentrations (1, 10 or 100 ppb for 60 min. At the end-point of exposure, the DMP-treated eggs and sperm were collected for analysis of their ultra-structures, ATPase activities and total lipid levels, and the fertilized gametes (embryos were collected to monitor related reproductive parameters (fertilization rate, abnormal development rate and hatching success rate. Treatment with DMP did not significantly alter the structure or total lipid content of eggs at any of the doses tested. Hatching failures and morphological abnormalities were only observed with the highest dose of DMP (100 ppb. However, DMP exposure did suppress sperm ATPase activities and affect the morphological character of their mitochondria. DMP-treated sperm exhibited dose-dependent decreases in fertilization efficiency, morphogenesis and hatchability. Relatively obvious toxicological effects were observed when both sperm and eggs were exposed to DMP. Furthermore, RT-PCR results indicate that treatment of gametes with DMP changed the expression patterns of physiologically-regulated genes (cyp3a, 17β-HSD-11 and 17β-HSD-12 in subsequent embryogenesis. Taken together, this study proofed that pre-fertilization exposure of abalone eggs, sperm or both to DMP adversely affects the fertilization process and subsequent embryogenesis.

  4. Evaluation of haemoglobin (erythrogen): for improved somatic embryogenesis and plant regeneration in cotton (Gossypium hirsutum L. cv. SVPR 2).

    Science.gov (United States)

    Ganesan, M; Jayabalan, N

    2004-10-01

    Somatic embryogenesis in cotton (Gossypium hirsutum L.) is accelerated when the plant regeneration medium is supplemented with haemoglobin (erythrogen). In cotton SVPR 2 lines, a higher frequency of embryoid formation was observed when the medium contained 400 mg/l haemoglobin. Fresh weight of the callus, rate of embryoid induction, number of embryoids formed and the percentage of plant regeneration from somatic embryos were increased. Among the two different cultivars tested, MCU 11 showed no response to the presence of haemoglobin when compared to SVPR 2, and embryogenic callus formation was completely absent in the former. Medium containing MS salts, 100 mg/l myo-inositol , 0.3 mg/l thiamine-HCL, 0.3 mg/l Picloram (PIC), 0.1 mg/l kinetin and 400 mg/l haemoglobin effected a better response with respect to embryogenic callus induction. After 8 weeks of culture, a high frequency of embryoid induction was observed on medium containing MS basal salts, 100 mg/l myo-inositol, 0.3 mg/l PIC , 0.1 mg/l isopentenyl adenine, 1.0 g/l NH4NO3 and 400 mg/l haemoglobin. Plant regeneration was observed in 75.8% of the mature somatic embryos, and whole plant regeneration was achieved within 6-7 months of culture. The regenerated plantlets were fertile and similar to in vivo-grown, seed-derived plants except that they were phenotypically smaller. A positive influence of haemoglobin was observed at concentrations up to 400 mg/l at all stages of somatic embryogenesis. The increase in the levels of antioxidant enzyme activities, for example superoxide dismutase and peroxidase, indicated the presence of excess oxygen uptake and the stressed condition of the plant tissues that arose from haemoglobin supplementation. This increased oxygen uptake and haemoglobin-mediated stress appeared to accelerate somatic embryogenesis in cotton.

  5. Stimulation of somatic embryogenesis and plant regeneration from anther culture of Vitis vinifera cv. Cabernet-Sauvignon.

    Science.gov (United States)

    Cl Mauro, M; Nef, C; Fallot, J

    1986-10-01

    Somatic embryogenesis and subsequent diploid plants have been obtained from anthers of Vitis vinifera Cabernet-Sauvignon, a cultivar so far considered as recalcitrant to in vitro regeneration. Anthers enclosing microspores near the first pollen mitosis were found to be the most responsive. However, from a practical point of view anther length proved to be an easier criterium for determining the optimal physiological anther stage. Calli derived from the anther somatic tissues produced embryoids only when cultured on a medium supplemented with casein hydrolysate. Glutamine and adenine were found to stimulate this embryoid production. Evidence is presented that early removal of cotyledons increases the frequency of normal development of embryoids into plantlets.

  6. Late-modern hipsters

    DEFF Research Database (Denmark)

    Andersen, Bjørn Schiermer

    2014-01-01

    The article deals with the cultural significance of a new figure in late-modern Western culture: the hipster. The current hipster culture, so I argue, can be used as a magnifying glass that makes impending changes to our conception of culture and of cultural development visible. It ushers in broa...... redemptive gesture toward the objects of the recent past and its predilection for irony. The article seeks to unfold hipster culture and sociality in an ongoing dialogue with sociological theory in general and conventional ways of thinking subculture in particular....

  7. Late-onset hypogonadism

    Directory of Open Access Journals (Sweden)

    Piotr Dudek

    2017-06-01

    Full Text Available In Poland, the number of men over the age of 50 years exceeds 6 million. It is estimated that about 2-6% of this population develops symptoms of late-onset hypogonadism (LOH. In men, testosterone deficiency increases slightly with age. LOH is a clinically and biochemically defined disease of older men with serum testosterone level below the reference parameters of younger healthy men and with symptoms of testosterone deficiency, manifested by pronounced disturbances of quality of life and harmful effects on multiple organ systems. Testosterone replacement therapy may give several benefits regarding body composition, metabolic control, and psychological and sexual parameters.

  8. Anther Culture of Chinese Radish ( Raphanus sativus L. var. Longinnatus Bailey): Response of Different Genotypes to the Embryogenesis and the Traits of Regenerated Plantlets

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li

    2011-01-01

    [ Objective] The aims were to ① conduct anther culture of Chinese radish varieties; ② observe the development of embryos from anther culture; ③ study the response of different genotypes to embryogenesis in anther culture; ④ observe the morphology of regenerated plantlets; ⑤ analyze the ploidy level of regenerated plantlets arising from the anther culture process. [ Method]Anthers of 15 genotypes with diverse genetic backgrounds of Chinese radish have been cultured in vitro and induced to undergo embryogenesis and plant formation. [Result] Of 15 genotypes evaluated, four produced embryos. The genotype was the main factor to influence the embryogenesis. The morphology and the ploidy of the regenerated plantlets were observed, and the anther-derived plantlets included a mix of haploids, diploids and hexaploids. Of the plants that regenerated from anther embryos 60% were diploid. [ Conclusion] The plantlets had the high ability to double spontaneously.

  9. Vegetative propagation of Quercus suber L. by somatic embryogenesis. I. Factors affecting the induction in leaves from mature cork oak trees.

    Science.gov (United States)

    Hernández, I; Celestino, C; Toribio, M

    2003-04-01

    Somatic embryogenesis was induced in expanding leaves from epicormic shoots forced to sprout from segments of branches collected from several hundred-year-old cork oak trees. Following a basic protocol previously defined for leaves taken from seedlings of this species, several factors were studied to improve the response. The induction frequency was significantly higher when the length of exposure to growth regulators was increased from 7 to 30 days. The combined application of NAA and BAP was essential for induction. Although both regulators had a very significant influence, their interaction was not significant, suggesting independent roles. Leaf size had a crucial effect, because beyond a certain threshold, embryogenesis could not be obtained. Embryogenic lines were maintained via repetitive embryogenesis on hormone-free medium for more than 2 years.

  10. Effects of doxycycline on heartworm embryogenesis, transmission, circulating microfilaria, and adult worms in microfilaremic dogs.

    Science.gov (United States)

    McCall, J W; Kramer, L; Genchi, C; Guerrero, J; Dzimianski, M T; Mansour, A; McCall, S D; Carson, B

    2014-11-15

    Tetracycline treatment of animals or humans infected with filariae that harbor Wolbachia endosymbionts blocks further embryogenesis, and existing microfilariae gradually die. This treatment also kills developing larvae and has a slow-kill effect on adult filariae, all presumably due to elimination of the Wolbachia. Also, Dirofilaria immitis microfilariae in blood collected from dogs up to 25 days after the last dose of doxycycline developed to infective L3 that were normal in appearance and motility in mosquitoes but did not continue to develop or migrate normally after subcutaneous (SC) injection into dogs. The present study was designed to determine whether heartworm microfilariae collected at later times after treatment would regain the ability to continue normal development in a dog. The study also was expected to yield valuable data on the effects of treatment on microfilariae and antigen levels and adult worms. The study was conducted in 16 dogs as two separate replicates at different times. A total of five dogs (two in Replicate A and three in Replicate B) infected either by SC injection of L3 or intravenous transplantation of adult heartworms were given doxycycline orally at 10mg/kg twice daily for 30 days, with three untreated controls. Microfilarial counts in the five treated dogs gradually declined during the 12-13 months after treatment initiation. Two dogs were amicrofilaremic before necropsy and three had 13 or fewer microfilariae/ml. Only one treated dog was negative for heartworm antigen before necropsy. Overall, treated dogs generally had fewer live adult heartworms than controls, and most of their live worms were moribund. All three control dogs remained positive for microfilariae and antigen and had many live worms. L3 from mosquitoes fed on blood collected 73-77 or 161-164 days after initiation of doxycycline treatments were injected SC into five dogs. None of the dogs injected with L3 from mosquitoes fed on blood from doxycycline-treated dogs

  11. Macondo crude oil from the Deepwater Horizon oil spill disrupts specific developmental processes during zebrafish embryogenesis

    Directory of Open Access Journals (Sweden)

    de Soysa T Yvanka

    2012-05-01

    Full Text Available Abstract Background The Deepwater Horizon disaster was the largest marine oil spill in history, and total vertical exposure of oil to the water column suggests it could impact an enormous diversity of ecosystems. The most vulnerable organisms are those encountering these pollutants during their early life stages. Water-soluble components of crude oil and specific polycyclic aromatic hydrocarbons have been shown to cause defects in cardiovascular and craniofacial development in a variety of teleost species, but the developmental origins of these defects have yet to be determined. We have adopted zebrafish, Danio rerio, as a model to test whether water accumulated fractions (WAF of the Deepwater Horizon oil could impact specific embryonic developmental processes. While not a native species to the Gulf waters, the developmental biology of zebrafish has been well characterized and makes it a powerful model system to reveal the cellular and molecular mechanisms behind Macondo crude toxicity. Results WAF of Macondo crude oil sampled during the oil spill was used to treat zebrafish throughout embryonic and larval development. Our results indicate that the Macondo crude oil causes a variety of significant defects in zebrafish embryogenesis, but these defects have specific developmental origins. WAF treatments caused defects in craniofacial development and circulatory function similar to previous reports, but we extend these results to show they are likely derived from an earlier defect in neural crest cell development. Moreover, we demonstrate that exposure to WAFs causes a variety of novel deformations in specific developmental processes, including programmed cell death, locomotor behavior, sensory and motor axon pathfinding, somitogenesis and muscle patterning. Interestingly, the severity of cell death and muscle phenotypes decreased over several months of repeated analysis, which was correlated with a rapid drop-off in the aromatic and alkane

  12. Plant regeneration through somatic embryogenesis and genome size analysis of Coriandrum sativum L.

    Science.gov (United States)

    Ali, Muzamil; Mujib, A; Tonk, Dipti; Zafar, Nadia

    2017-01-01

    In the present study, an improved plant regeneration protocol via primary and secondary somatic embryogenesis was established in two Co-1 and Rajendra Swathi (RS) varieties of Coriandrum sativum L. Callus was induced from root explants on 2, 4-D (0.5-2.0 mg/l) supplemented MS. The addition of BA (0.2 mg/l) improved callus induction and proliferation response significantly. The maximum callus induction frequency was on 1.0 mg/l 2, 4-D and 0.2 mg/l BA added MS medium (77.5 % in Co-1 and 72.3 % in RS). The callus transformed into embryogenic callus on 2, 4-D added MS with maximum embryogenic frequency was on 1.0 mg/l. The granular embryogenic callus differentiated into globular embryos on induction medium, which later progressed to heart-, torpedo- and cotyledonary embryos on medium amended with 0.5 mg/l NAA and 0.2 mg/l BA. On an average, 2-3 secondary somatic embryos (SEs) were developed on mature primary SEs, which increased the total embryo numbers in culture. Histology and scanning electron microscopy (SEM) studies are presented for the origin, development of primary and secondary embryos in coriander. Later, these induced embryos converted into plantlets on 1.0 mg/l BA and 0.2 mg/l NAA-amended medium. The regenerated plantlets were cultured on 0.5 mg/l IBA added ½ MS for promotion of roots. The well-rooted plantlets were acclimatized and transferred to soil. The genetic stability of embryo-regenerated plant was analyzed by flow cytometry with optimized Pongamia pinnata as standard. The 2C DNA content of RS coriander variety was estimated to 5.1 pg; the primary and secondary somatic embryo-derived plants had 5.26 and 5.44 pg 2C DNA content, respectively. The regenerated plants were genetically stable, genome size similar to seed-germinated coriander plants.

  13. Transcriptional profiling of genes involved in embryogenic, non-embryogenic calluses and somatic embryogenesis of Valencia sweet orange by SSH-based microarray.

    Science.gov (United States)

    Ge, Xiao-Xia; Chai, Li-Jun; Liu, Zheng; Wu, Xiao-Meng; Deng, Xiu-Xin; Guo, Wen-Wu

    2012-10-01

    Somatic embryogenesis (SE) is a most promising technology that is used for in vitro germplasm conservation and genetic improvement via biotechnological approaches in citrus. Herein, three suppression subtractive hybridization (SSH) libraries were constructed using calluses of Citrus sinensis cv. 'Valencia' to explore the molecular mechanisms that underlie the SE in citrus. A total of 880 unisequences were identified by microarray screening based on these three SSH libraries. Gene ontology analysis of the differentially expressed genes indicated that nucleolus associated regulation and biogenesis processes, hormone signal transduction, and stress factors might be involved in SE. Transcription factors might also play an important role. LEC1/B3 domain regulatory network genes (LEC1, L1L, FUS3, ABI3, and ABI5) were isolated in citrus SE. Some new transcription factors associated with citrus SE, like a B3 domain containing gene and HB4, were identified. To understand the influence of these isolated genes on SE competence, their expression profiles were compared among callus lines of seven citrus cultivars with different SE competence. The expression dynamics suggested that these genes could be necessary for the SE initiation and might play a role in embryogenic competence maintenance in different cultivars. On the basis of gene expression profiles, an overview of major physiological and biosynthesis processes at different developmental stages during citrus SE is presented. For the first time, these data provide a global resource for transcriptional events important for SE in citrus, and the specific genes offer new information for further investigation on citrus SE maintenance and development.

  14. BnPME is progressively induced after microspore reprogramming to embryogenesis, correlating with pectin de-esterification and cell differentiation in Brassica napus.

    Science.gov (United States)

    Solís, María-Teresa; Berenguer, Eduardo; Risueño, María C; Testillano, Pilar S

    2016-08-11

    Pectins are one of the main components of plant cell walls. They are secreted to the wall as highly methylesterified forms that can be de-esterified by pectin methylesterases (PMEs). The degree of methylesterification of pectins changes during development, PMEs are involved in the cell wall remodeling that occurs during diverse plant developmental processes. Nevertheless, the functional meaning of pectin-related wall remodeling in different cell types and processes remains unclear. In vivo, the microspore follows the gametophytic pathway and differentiates to form the pollen grain. In vitro, the microspore can be reprogrammed by stress treatments becoming a totipotent cell that starts to proliferate and follows the embryogenic pathway, a process known as microspore embryogenesis. To investigate if the change of developmental programme of the microspore towards embryogenesis involves changes in pectin esterification levels, which would cause the cell wall remodeling during the process, in the present study, dynamics of PME expression and degrees of pectin esterification have been analysed during microspore embryogenesis and compared with the gametophytic development, in Brassica napus. A multidisciplinary approach has been adopted including BnPME gene expression analysis by quantitative RT-PCR, fluorescence in situ hybridization, immuno-dot-blot and immunofluorescence with JIM5 and JIM7 antibodies to reveal low and highly-methylesterified pectins. The results showed that cell differentiation at advanced developmental stages involved induction of BnPME expression and pectin de-esterification, processes that were also detected in zygotic embryos, providing additional evidence that microspore embryogenesis mimics zygotic embryogenesis. By contrast, early microspore embryogenesis, totipotency and proliferation were associated with low expression of BnPME and high levels of esterified pectins. The results show that the change of developmental programme of the microspore

  15. Somatic Embryogenesis in Coffee: The Evolution of Biotechnology and the Integration of Omics Technologies Offer Great Opportunities.

    Science.gov (United States)

    Campos, Nádia A; Panis, Bart; Carpentier, Sebastien C

    2017-01-01

    One of the most important crops cultivated around the world is coffee. There are two main cultivated species, Coffea arabica and C. canephora. Both species are difficult to improve through conventional breeding, taking at least 20 years to produce a new cultivar. Biotechnological tools such as genetic transformation, micropropagation and somatic embryogenesis (SE) have been extensively studied in order to provide practical results for coffee improvement. While genetic transformation got many attention in the past and is booming with the CRISPR technology, micropropagation and SE are still the major bottle neck and urgently need more attention. The methodologies to induce SE and the further development of the embryos are genotype-dependent, what leads to an almost empirical development of specific protocols for each cultivar or clone. This is a serious limitation and excludes a general comprehensive understanding of the process as a whole. The aim of this review is to provide an overview of which achievements and molecular insights have been gained in (coffee) somatic embryogenesis and encourage researchers to invest further in the in vitro technology and combine it with the latest omics techniques (genomics, transcriptomics, proteomics, metabolomics, and phenomics). We conclude that the evolution of biotechnology and the integration of omics technologies offer great opportunities to (i) optimize the production process of SE and the subsequent conversion into rooted plantlets and (ii) to screen for possible somaclonal variation. However, currently the usage of the latest biotechnology did not pass the stage beyond proof of potential and needs to further improve.

  16. Bottlenecks in bog pine multiplication by somatic embryogenesis and their visualization with the environmental scanning electron microscope.

    Science.gov (United States)

    Vlašínová, Helena; Neděla, Vilem; Đorđević, Biljana; Havel, Ladislav

    2017-07-01

    Somatic embryogenesis (SE) is an important biotechnological technique used for the propagation of many pine species in vitro. However, in bog pine, one of the most endangered tree species in the Czech Republic, limitations were observed, which negatively influenced the development and further germination of somatic embryos. Although initiation frequency was very low-0.95 %, all obtained cell lines were subjected to maturation. The best responding cell line (BC1) was used and subjected to six different variants of the maturation media. The media on which the highest number of early-precotyledonary/cotyledonary somatic embryos was formed was supplemented with 121 μM abscisic acid (ABA) and with 6 % maltose. In the end of maturation experiments, different abnormalities in formation of somatic embryos were observed. For visualization and identification of abnormalities in meristem development during proliferation and maturation processes, the environmental scanning electron microscope was used. In comparison to the classical light microscope, the non-commercial environmental scanning electron microscope AQUASEM II has been found as a very useful tool for the quick recognition of apical meristem disruption and abnormal development. To our knowledge, this is the first report discussing somatic embryogenesis in bog pine. Based on this observation, the cultivation procedure could be enhanced and the method for SE of bog pine optimized.

  17. Effect of the combination of NAA, kinetin and sucrose on the induction of somatic embryogenesis in lulo (Solanum quitoense Lam.

    Directory of Open Access Journals (Sweden)

    Hernando Criollo

    2014-08-01

    Full Text Available Lulo is a species of great importance to the fruticulture of Colombia, but has significant phytosanitary problems that require an aggressive breeding program oriented toward the production of genotypes with tolerance to phytopathogens. These programs need to establish highly efficient mass plant propagation protocols, such as somatic embryogenesis. This study focused on research on the somatic embryogenesis of lulo using kinetin, naphthalene acetic acid-NAA (Plant Growth Regulators, PGRs, and different sucrose concentrations in a MS medium. Two lulo varieties, Solanum quitoense var. septentrionale and S. quitoense var. quitoense, and two explant types (hypocotyl and cotyledon were used, incubated in dark conditions at 25±2°C. The highest production percentage of the embryos was obtained when 50 muM of NAA were added to the medium with sucrose (50.0 and 263.1 muM for the two explant types used. In lulo with spines, the highest percentage of embryonic structures (50% was observed with cotyledonary leaf explants and 50 muM of NAA ; while in the spineless lulo, the embryonic structures were observed in the same type of explant with 50 muM of NAA + 263.1 muM of sucrose (32%.

  18. G-protein-coupled estrogen receptor 1 is involved in brain development during zebrafish (Danio rerio) embryogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Yanan; Liu, Xiaochun [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); Zhu, Pei; Li, Jianzhen; Sham, Kathy W.Y. [School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Cheng, Shuk Han [Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong (China); Li, Shuisheng; Zhang, Yong [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); Cheng, Christopher H.K., E-mail: chkcheng@cuhk.edu.hk [School of Biomedical Sciences, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong (China); Lin, Haoran, E-mail: lsslhr@mail.sysu.edu.cn [State Key Laboratory of Biocontrol, Institute of Aquatic Economic Animals and Guangdong Provincial Key Laboratory for Aquatic Economic Animals, School of Life Sciences, Sun Yat-Sen University, Guangzhou 510275 (China); College of Ocean, Hainan University, Haikou 570228, Hainan (China)

    2013-05-24

    Highlights: •The Gper expression was detected in the developing brain of zebrafish. •Gper morpholino knockdown induced apoptosis of brain cells. •Gper morpholino knockdown reduced expression in neuron markers. •Zebrafish Gper may be involved in neuronal development. -- Abstract: G-protein-coupled estrogen receptor 1 (Gper, formerly known as GPR30) is found to be a trophic and protective factor in mediating action of estrogen in adult brain, while its role in developing brain remains to be elucidated. Here we present the expression pattern of Gper and its functions during embryogenesis in zebrafish. Both the mRNA and protein of Gper were detected throughout embryogenesis. Whole mount in situ hybridization (WISH) revealed a wide distribution of gper mRNAs in various regions of the developing brain. Gper knockdown by specific morpholinos resulted in growth retardation in embryos and morphological defects in the developing brain. In addition, induced apoptosis, decreased proliferation of the brain cells and maldevelopment of sensory and motor neurons were also found in the morphants. Our results provide novel insights into Gper functions in the developing brain, revealing that Gper can maintain the survival of the brain cells, and formation and/or differentiation of the sensory and motor neurons.

  19. Somatic embryogenesis of Echinodorus orisis L. and the kinetic changes of the endogenous hormones contents during the embryogenetic process.

    Science.gov (United States)

    Xing, D; Zhao, Y; Huang, C

    1999-01-01

    Somatic embryogenesis was achieved in young Leaf cuttings of Echinodorus orisis L., an aquatic ornamental plant, in a short period (25 days). Among the cytokinins and their combinations tested, 6-BA (1 mg/L) and Zt (1 mg/L) in MS medium induced the highest efficiency (100%) of somatic embryogenesis, with a maximum of 4.87 embryoids per explant. Roots instead of somatic embryos were formed when NAA (0.5 mg/L) was added to MS medium containing Zt (1 mg/L). Matured embryoids were germinated and rooted in MS medium with IAA (1 mg/L) after 5 days cultivation. Seventy-two percent of the rooted plantlets transplanted survived in the aquarium. The endogenous hormone contents in various stages of somatic embryogenetic process were measured by HPLC. The concentrations of all the hormones tested were about 2 times that of the cuttings from the untreated fresh leaves after 10 days incubation. Meanwhile, the concentration of IAA presents two peaks after 10 and 25 days of cultivation, respectively. The cytokinin (Zt and ZR) peak, about 8 times more than CK, appeared in 15 days cultivation when the heart-shaped embryos formed. The fluctuation of the GA3 concentration was very similar to that of cytokinin. The ABA, however, remains stable at quite high concentration after 10 days of cultivation.

  20. Embriogênese somática do caquizeiro Somatic embryogenesis of japanese persimmon

    Directory of Open Access Journals (Sweden)

    Dayse Cristina de Carvalho

    2004-08-01

    through somatic embryogenesis. Zygotic embryos excised from fruits collected from adult plants were tested at several developmental phases. They were collected during 22 weeks after 4 weeks blossoming. The basic medium tested was MS½NO3. Initial induction medium was supplemented with 20 µM 2,4-D + 2 µM kinetin. Dark calluses obtained were transferred to induction medium, with concentrations of 10 and 20 µM 2,4-D + 2 µM kinetin. The calli with pro-embryogenic masses were transferred to a maintenance and multiplication medium, with 2 µM kinetin and 2,4-D at the concentrations of 2.5, 5.0 and 10 µM. Embryogenic masses formed were transferred to a maturation medium supplemented with 0.5 µM IBA and 5, 10 and 20 µM 2iP. Embryos formed were isolated in two conversion media, one with 5 µM 2-iP + 5 µM GA3 and 0.5 µM IBA, and another medium with 0.5 µM GA3 and BAP at 0, 0.25, 0.5 and 1.0 µM. Indirect somatic embryogenesis were obtained from mature zygotic embryos collected after 22 weeks, when cultivated in culture medium with 10 µM 2,4D combined with 2 µM kinetin. Embryos maintenance and multiplication were more efficient with 5 µM 2,4-D, in which the pro-embryos advanced to the globular embryos phase. At the maturation phase the concentrations of 2-iP tested promoted globular embryos to more advanced stages of ontogeny, such as cordiform, torpedo and cotiledonary. Supplementation of the culture medium with 1 µM BAP generated better developed plants, with highest number of leaves and size.

  1. Late effects of thoracic irradiation in children

    Energy Technology Data Exchange (ETDEWEB)

    Boelling, T.; Koenemann, S.; Ernst, I.; Willich, N. [Dept. of Radiotherapy, Univ. Hospital of Muenster (Germany)

    2008-06-15

    Purpose: to summarize the literature regarding the late effects of radiotherapy to the thorax in childhood and adolescence with special emphasis on cardiac and pulmonary impairment. Material und methods: the literature was critically reviewed using the PubMed {sup registered} database with the key words 'late effects', 'late sequelae', 'child', 'childhood', 'adolescence', 'radiation', 'radiotherapy', 'thorax', 'lung', 'heart', and 'pulmonary'. Results: 17 publications dealing with radiation-induced pulmonary and cardiac late sequelae in children could be identified and were analyzed in detail. 29 further publications with additional information were also included in the analysis. Pulmonary function impairment after mediastinal irradiation arose in one third of all pediatric patients, even when treatment was performed with normofractionated lower doses (15-25 Gy). Whole lung irradiation was regularly followed by pulmonary function impairment with differing rates in several reports. However, clinically symptomatic function impairment like dyspnea was less frequent. Irradiation of up to 25 Gy (single doses {<=} 2 Gy) to the heart showed little or no cardiac toxicity in analyses of irradiated children (median follow-up 1.3-14.3 years). Doses of > 25 Gy (single doses {<=} 2-3.3 Gy) led to several cardiac dysfunctions. However, new data from adults with longer follow-up may indicate threshold doses as low as 1 Gy. Impairment of skeletal growth, breast hypoplasia, and secondary malignancy were further potential late sequelae. Conclusion: several retrospective reports described radiation-associated late sequelae in children. However, there is still a lack of sufficient data regarding the characterization of dose-volume effects. (orig.)

  2. Never too late.

    Science.gov (United States)

    1996-11-01

    Motivated by the belief that education has been central to Japan's economic success, Japan International Cooperation Agency (JICA) promotes universal access to quality basic education. In developing countries, school children rarely learn science through experiments. A new JICA training course, the Science Experiment in Primary Education, involved teacher trainers from Bangladesh, Myanmar, Pakistan, and Sri Lanka. Physics, chemistry, biology, geology, and astronomy experiments that require simple, inexpensive materials were taught. Another JICA project in Satkhira, Bangladesh, sought to raise the economic status of women enrolled in a dressmaking program through a year-long evening literacy class at three sites. Elementary school diplomas (available with proof to a local teacher of basic literacy and minimal arithmetic skills) are required in Bangladesh to apply for nongovernmental organization-initiated vocational schools and loans to start businesses in areas such as dressmaking, agriculture, and livestock raising. By late 1993, the female literacy program had expanded to 18 villages.

  3. Late-Modern Symbolism

    DEFF Research Database (Denmark)

    Andersen, Bjørn Schiermer

    2015-01-01

    Through analysis of key texts, I seek to demonstrate the explanative potential of Durkheim’s sociology of religion in the present context. I critically readdress the idea, found in his early work, that modernity is characterized by a rupture with pre-modern forms of solidarity. First, I investigate...... the ways in which Durkheim sets up a stark distinction between the pre-modern and the modern in his early work, and how this distinction is further cemented by his orthodox critique of the modern economy and its negative effects on social life. Second, I show how another timeless and positive understanding...... of “mechanical” solidarity is to be found behind the “symbolist” template crystalizing in Durkheim’s late work. Third, I develop this template for a modern context by critically addressing and removing other obstacles and prejudices on Durkheim’s part....

  4. Center Variation in the Delivery of Indicated Late Preterm Births.

    Science.gov (United States)

    Aliaga, Sofia; Zhang, Jun; Long, D Leann; Herring, Amy H; Laughon, Matthew; Boggess, Kim; Reddy, Uma M; Grantz, Katherine Laughon

    2016-08-01

    Objective Evidence for optimal timing of delivery for some pregnancy complications at late preterm gestation is limited. The purpose of this study was to identify center variation of indicated late preterm births. Study design We performed an analysis of singleton late preterm and term births from a large U.S. retrospective obstetrical cohort. Births associated with spontaneous preterm labor, major congenital anomalies, chorioamnionitis, and emergency cesarean were excluded. We used modified Poisson fixed effects logistic regression with interaction terms to assess center variation of indicated late preterm births associated with four medical/obstetric comorbidities after adjusting for socio-demographics, comorbidities, and hospital/provider characteristics. Results We identified 150,055 births from 16 hospitals; 9,218 were indicated late preterm births. We found wide variation of indicated late preterm births across hospitals. The extent of center variation was greater for births associated with preterm premature rupture of membranes (risk ratio [RR] across sites: 0.45-3.05), hypertensive disorders of pregnancy (RR across sites: 0.36-1.27), and placenta previa/abruption (RR across sites: 0.48-1.82). We found less center variation for births associated with diabetes (RR across sites: 0.65-1.39). Conclusion Practice variation in the management of indicated late preterm deliveries might be a source of preventable late preterm birth.

  5. Late Carboniferous to Late Permian carbon isotope stratigraphy

    DEFF Research Database (Denmark)

    Buggisch, Werner; Krainer, Karl; Schaffhauser, Maria

    2015-01-01

    An integrated study of the litho-, bio-, and isotope stratigraphy of carbonates in the Southern Alps was undertaken in order to better constrain δ13C variations during the Late Carboniferous to Late Permian. The presented high resolution isotope curves are based on 1299 δ13Ccarb and 396 δ13Corg a...

  6. Late Talkers: A Population-Based Study of Risk Factors and School Readiness Consequences

    Science.gov (United States)

    Hammer, Carol Scheffner; Morgan, Paul; Farkas, George; Hillemeier, Marianne; Bitetti, Dana; Maczuga, Steve

    2017-01-01

    Purpose: This study was designed to (a) identify sociodemographic, pregnancy and birth, family health, and parenting and child care risk factors for being a late talker at 24 months of age; (b) determine whether late talkers continue to have low vocabulary at 48 months; and (c) investigate whether being a late talker plays a unique role in…

  7. Late glacial aridity in southern Rocky Mountains

    Energy Technology Data Exchange (ETDEWEB)

    Davis, O.K.; Pitblado, B.L. [Univ. of Arizona, Tucson, AZ (United States)

    1995-09-01

    While the slopes of the present-day Colorado Rocky Mountains are characterized by large stands of subalpine and montane conifers, the Rockies of the late glacial looked dramatically different. Specifically, pollen records suggest that during the late glacial, Artemisia and Gramineae predominated throughout the mountains of Colorado. At some point between 11,000 and 10,000 B.P., however, both Artemisia and grasses underwent a dramatic decline, which can be identified in virtually every pollen diagram produced for Colorado mountain sites, including Como Lake (Sangre de Cristo Mountains), Copley Lake and Splains; Gulch (near Crested Butte), Molas Lake (San Juan Mountains), and Redrock Lake (Boulder County). Moreover, the same pattern seems to hold for pollen spectra derived for areas adjacent to Colorado, including at sites in the Chuska Mountains of New Mexico and in eastern Wyoming. The implications of this consistent finding are compelling. The closest modem analogues to the Artemisia- and Gramineae-dominated late-glacial Colorado Rockies are found in the relatively arid northern Great Basin, which suggests that annual precipitation was much lower in the late-glacial southern Rocky Mountains than it was throughout the Holocene.

  8. Genome-wide identification, classification and analysis of HD-ZIP gene family in citrus, and its potential roles in somatic embryogenesis regulation.

    Science.gov (United States)

    Ge, Xiao-Xia; Liu, Zheng; Wu, Xiao-Meng; Chai, Li-Jun; Guo, Wen-Wu

    2015-12-10

    The homeodomain-leucine zipper (HD-Zip) transcription factors, which belong to a class of Homeobox proteins, has been reported to be involved in different biological processes of plants, including growth and development, photomorphogenesis, flowering, fruit ripening and adaptation responses to environmental stresses. In this study, 27 HD-Zip genes (CsHBs) were identified in Citrus. Based on the phylogenetic analysis and characteristics of individual gene or protein, the HD-Zip gene family in Citrus can be classified into 4 subfamilies, i.e. HD-Zip I, HD-Zip II, HD-Zip III, and HD-Zip IV containing 16, 2, 4, and 5 members respectively. The digital expression patterns of 27 HD-Zip genes were analyzed in the callus, flower, leaf and fruit of Citrus sinensis. The qRT-PCR and RT-PCR analyses of six selected HD-Zip genes were performed in six citrus cultivars with different embryogenic competence and in the embryo induction stages, which revealed that these genes were differentially expressed and might be involved in citrus somatic embryogenesis (SE). The results exhibited that the expression of CsHB1 was up-regulated in somatic embryo induction process, and its expression was higher in citrus cultivars with high embryogenic capacity than in cultivars recalcitrant to form somatic embryos. Moreover, a microsatellite site of three nucleotide repeats was found in CsHB1 gene among eighteen citrus genotypes, indicating the possible association of CsHB1 gene to the capacity of callus induction. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. High expression of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE coincides with initiation of various developmental pathways in in vitro culture of Trifolium nigrescens.

    Science.gov (United States)

    Pilarska, Maria; Malec, Przemysław; Salaj, Jan; Bartnicki, Filip; Konieczny, Robert

    2016-03-01

    The aim of this study was to identify and examine the expression pattern of the ortholog of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE gene from Trifolium nigrescens (TnSERK) in embryogenic and non-regenerative cultures of immature cotyledonary-stage zygotic embryos (CsZEs). In the presence of 1-naphthaleneacetic acid and N(6)-[2-isopentenyl]-adenine, the CsZE regenerated embryoids directly and in a lengthy culture produced callus which was embryogenic or remained non-regenerative. As revealed by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), the TnSERK was expressed in both embryogenic and non-regenerative cultures, but the expression level was significantly higher in embryogenic ones. An in situ RNA hybridization assay revealed that the expression of TnSERK preceded the induction of cell division in explants, and then, it was maintained exclusively in actively dividing cells from which embryoids, embryo-like structures (ELSs), callus or tracheary elements were produced. However, the cells involved in different morphogenic events differed in intensity of hybridization signal which was the highest in embryogenic cells. The TnSERK was up-regulated during the development of embryoids, but in cotyledonary embryos, it was preferentially expressed in the regions of the apical meristems. The occurrence of morphological and anatomical abnormalities in embryoid development was preceded by a decline in TnSERK expression, and this coincided with the parenchymatization of the ground tissue in developing ELSs. TnSERK was also down-regulated during the maturation of parenchyma and xylem elements in CsZE and callus. Altogether, these data suggest the involvement of TnSERK in the induction of various developmental programs related to differentiation/transdifferentiation and totipotent state of cell(s).

  10. Late presentation of HIV infection: a consensus definition

    DEFF Research Database (Denmark)

    Antinori, A; Coenen, T; Costagiola, D

    2010-01-01

    clinical definition of late presentation. The objective of this article is to present a consensus definition of late presentation of HIV infection. Methods Over the past year, two initiatives have moved towards a harmonized definition. In spring 2009, they joined efforts to identify a common definition...... of what is meant by a 'late-presenting' patient. Results Two definitions were agreed upon, as follows. Late presentation: persons presenting for care with a CD4 count below 350 cells/muL or presenting with an AIDS-defining event, regardless of the CD4 cell count. Presentation with advanced HIV disease...... able to implement this definition (either on its own or alongside their own preferred definition) when reporting surveillance or research data relating to late presentation of HIV infection....

  11. Illusory Late Heavy Bombardments.

    Science.gov (United States)

    Boehnke, Patrick; Harrison, T Mark

    2016-09-27

    The Late Heavy Bombardment (LHB), a hypothesized impact spike at ∼3.9 Ga, is one of the major scientific concepts to emerge from Apollo-era lunar exploration. A significant portion of the evidence for the existence of the LHB comes from histograms of (40)Ar/(39)Ar "plateau" ages (i.e., regions selected on the basis of apparent isochroneity). However, due to lunar magmatism and overprinting from subsequent impact events, virtually all Apollo-era samples show evidence for (40)Ar/(39)Ar age spectrum disturbances, leaving open the possibility that partial (40)Ar* resetting could bias interpretation of bombardment histories due to plateaus yielding misleadingly young ages. We examine this possibility through a physical model of (40)Ar* diffusion in Apollo samples and test the uniqueness of the impact histories obtained by inverting plateau age histograms. Our results show that plateau histograms tend to yield age peaks, even in those cases where the input impact curve did not contain such a spike, in part due to the episodic nature of lunar crust or parent body formation. Restated, monotonically declining impact histories yield apparent age peaks that could be misinterpreted as LHB-type events. We further conclude that the assignment of apparent (40)Ar/(39)Ar plateau ages bears an undesirably high degree of subjectivity. When compounded by inappropriate interpretations of histograms constructed from plateau ages, interpretation of apparent, but illusory, impact spikes is likely.

  12. Improving initiation, genotype capture, and family representation in somatic embryogenesis of Pinus radiata by a combination of zygotic embryo maturity, media, and explant preparation

    DEFF Research Database (Denmark)

    Hargreaves, Cathy; Find, Jens; Reeves, Cathie;

    2009-01-01

    The principal aim of this investigation was to improve somatic embryogenesis initiation and to enhance representation of families and genotypes within those families of Pinus radiata D. Don. A total of 19 open-pollinated seed families, many with unrelated and weakly related parents, were tested. ...

  13. ADP-ribosylation factor-like protein 4C (ARL4C) interacts with galectin-3 during oocyte development and embryogenesis in rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    ADP-ribosylation factor-like protein 4 (ARL4) is a GTP-binding protein which belongs to the ADP-ribosylation factor protein (ARF) superfamily of small GTPases. ARL4 has been shown to be mainly related to the development of male germ cells and embryogenesis in mouse. To investigate the role of ARL4 i...

  14. Study of the embryogenesis of Dunhevedia crassa King, 1853 (Cladocera: Chydoridae and a comparison of embryonic instar durations in different cladocerans

    Directory of Open Access Journals (Sweden)

    Alexey A. Kotov

    2013-10-01

    Full Text Available The aim of this work is to study the embryonic development of a common tropical cladoceran Dunhevedia crassa King, 1853 (Anomopoda:Chydoridae and compare the durations of embryonic instars and growth during embryogenesis in small-sized chydorids and other cladocerans. The sequence of events in the embryogenesis of Dunhevedia females was studied by means of in vitro observation in the laboratory at 28.5°C. We found that the general pattern of the sequence of events in chydorid embryogenesis is similar to that in other anomopods. However, the relative durations of the embryonic instars I and II+III are markedly short, while that of instar IV is long (delayed when compared with other cladocerans. The observed pattern of ontogenesis in chydorids may therefore be apomorphic within the cladocerans and could reflect a neotenic evolution. Another peculiar trait of Dunhevedia is the very small increase of the size of the embryo during embryogenesis, which is correlated with a very large size of the egg relative to the mother. Therefore, our study revealed some peculiarities in the ontogenesis of small-sized chydorids, which could be a result of family-specific evolution.

  15. Recent casualties of late globalization

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2016-01-01

    In this essay I will expand my thoughts on universities as ‘late globalizers’ and the impact ‘being late’ has on university internationalization or globalization activities. In my earlier essay I viewed universities as ‘late globalizers’ and briefly introduced the impact of being ‘late’, e...

  16. Recent casualties of late globalization

    DEFF Research Database (Denmark)

    Turcan, Romeo V.

    2016-01-01

    In this essay I will expand my thoughts on universities as ‘late globalizers’ and the impact ‘being late’ has on university internationalization or globalization activities. In my earlier essay I viewed universities as ‘late globalizers’ and briefly introduced the impact of being ‘late’, e.g., wi...

  17. Changes in ecdysteroid levels and expression patterns of ecdysteroid-responsive factors and neuropeptide hormones during the embryogenesis of the blue crab, Callinectes sapidus.

    Science.gov (United States)

    Techa, Sirinart; Alvarez, Javier V; Sook Chung, J

    2015-04-01

    Embryogenesis requires the involvement and coordination of multiple networks of various genes, according to a timeline governing development. Crustacean embryogenesis usually includes the first molt, a process that is known to be positively controlled by ecdysteroids. We determined the amounts of ecdysteroids, as well as other related factors: the ecdysone receptor (CasEcR), the retinoid X receptor (CasRXR), the molt-inhibiting hormone (CasMIH), and crustacean hyperglycemic hormone (CasCHH) during the ovarian and embryonic developments of Callinectes sapidus. In summary, the ovaries at stages 1-4 have expression levels of maternal CasEcR and CasRXR 10-50 times higher than levels seen in embryos at the yolk stage. This large difference in the amount of the these factors in C. sapidus ovaries suggests that these maternal ecdysteroid-responsive factors may be utilized at the initiation of embryogenesis. During embryogenesis, the changes in total ecdysteroids and levels of CasEcR and CasRXR expression are similar to those observed in juvenile molts. The full-length cDNA sequence of the C. sapidus BTB domain protein (CasBTBDP) initially isolated from Y-organ cDNA, contains only Broad-Complex, Tramtrack, and Bric a brac (BTB) domains. The levels of CasBTBDP are kept constant throughout embryogenesis. The expression profiles of CasMIH and CasCHH are similar to the titers of ecdysteroids. However, the timing of their appearance is followed by increases in CasEcRs and CasRXRs, implying that the expressions of these neuropeptides may be influenced by ecdysteroids. Moreover, the ecdysteroid profile during embryogenesis may track directly with the timing of organogenesis of Y-organs and their activity. Our work reports, for first time, the observed expression and changes of ecdysteroid-responsive factors, along with CasCHH and CasMIH, during embryogenesis in the crustacean C. sapidus. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. Differential gene expression in soybean leaf tissues at late developmental stages under drought stress revealed by genome-wide transcriptome analysis.

    Directory of Open Access Journals (Sweden)

    Dung Tien Le

    Full Text Available The availability of complete genome sequence of soybean has allowed research community to design the 66 K Affymetrix Soybean Array GeneChip for genome-wide expression profiling of soybean. In this study, we carried out microarray analysis of leaf tissues of soybean plants, which were subjected to drought stress from late vegetative V6 and from full bloom reproductive R2 stages. Our data analyses showed that out of 46,093 soybean genes, which were predicted with high confidence among approximately 66,000 putative genes, 41,059 genes could be assigned with a known function. Using the criteria of a ratio change > = 2 and a q-value<0.05, we identified 1458 and 1818 upregulated and 1582 and 1688 downregulated genes in drought-stressed V6 and R2 leaves, respectively. These datasets were classified into 19 most abundant biological categories with similar proportions. There were only 612 and 463 genes that were overlapped among the upregulated and downregulated genes, respectively, in both stages, suggesting that both conserved and unconserved pathways might be involved in regulation of drought response in different stages of plant development. A comparative expression analysis using our datasets and that of drought stressed Arabidopsis leaves revealed the existence of both conserved and species-specific mechanisms that regulate drought responses. Many upregulated genes encode either regulatory proteins, such as transcription factors, including those with high homology to Arabidopsis DREB, NAC, AREB and ZAT/STZ transcription factors, kinases and two-component system members, or functional proteins, e.g. late embryogenesis-abundant proteins, glycosyltransferases, glycoside hydrolases, defensins and glyoxalase I family proteins. A detailed analysis of the GmNAC family and the hormone-related gene category showed that expression of many GmNAC and hormone-related genes was altered by drought in V6 and/or R2 leaves. Additionally, the downregulation of

  19. LATE RENAL GRAFT REJECTION: PATHOLOGY AND PROGNOSIS

    Directory of Open Access Journals (Sweden)

    E.S. Stolyarevich

    2014-01-01

    Full Text Available Rejection has always been one of the most important cause of late renal graft dysfunction. Aim of the study was to analyze the prevalence of different clinico-pathological variants of rejection that cause late graft dysfunction, and evaluate their impact on long-term outcome. Materials and methods. This is a retrospective study that analyzed 294 needle core biopsy specimens from 265 renal transplant recipients with late (48,8 ± 46,1 months after transplantation allograft dysfunction caused by late acute rejection (LAR, n = 193 or chronic rejection (CR, n = 78 or both (n = 23. C4d staining was performed by immunofl uorescence (IF on frozen sections using a standard protocol. Results. Peritubular capillary C4d deposition was identifi ed in 36% samples with acute rejection and in 62% cases of chronic rejection (including 67% cases of transplant glomerulopathy, and 50% – of isolated chronic vasculopathy. 5-year graft survival for LAR vs CR vs their combination was 47, 13 and 25%, respectively. The outcome of C4d– LAR was (p < 0,01 better than of C4d+ acute rejection: at 60 months graft survival for diffuse C4d+ vs C4d− was 33% vs 53%, respectively. In cases of chronic rejection C4d+ vs C4d– it was not statistically signifi cant (34% vs 36%. Conclusion. In long-term allograft biopsy C4d positivity is more haracteristic for chronic rejection than for acute rejection. Only diffuse C4d staining affects the outcome. C4d– positivity is associated with worse allograft survival in cases of late acute rejection, but not in cases of chronic rejection. 

  20. Late-life attachment.

    Science.gov (United States)

    Freitas, Mélanie; Rahioui, Hassan

    2017-03-01

    Old age is likely to cause a crisis in one's life because of the vulnerabilities it brings up, acting as stressful elements disrupting the elder's feeling of security. It leads to the activation of what is called his attachment system, consisting in attachment styles and interpersonal emotional regulation strategies. To recover a higher sense of safety, the elder would refer to his attachment figures, that is to say closed people paying attention to him, showing towards him availability and consideration. However older adults particularly see their tolerance threshold lowered, regarding an accumulation of losses (true or symbolic) and stressful events within their lifetime. In a psychological and organic exhaustion phenomenon, the risk is to wear out the interpersonal emotional regulation strategies. These are as much vulnerabilities that may increase psychiatric decompensation, including depression. To resolve the tension of this period and to found a necessary secure feeling, the elder will have to redesign the attachment links previously settled and proceed to adjustments to this new context. The need of relational closeness comes back in the elders' attachment behaviour, counting on attachment figures not only to help their loneliness or dependency, but essentially to support them in a narcissist and affective way. That is why attachment theory enlightens the late life period, such as the new challenges older adults have to face. Many studies recognize its value in understanding the transition to old age, but without proposing conceptualization. We aim first to focus on attachment conception to say how much it is relevant with elderly, and then to describe specific terms of attachment within this population in order to better understand those patients. To finish, we must think about new therapeutic proposals taking into consideration the attachment perspective for a better understanding of old age transition.

  1. Functional expression of opioid receptor—like receptor and its endogenous specific agonist nociceptin/orphanin FQ during mouse embryogenesis

    Institute of Scientific and Technical Information of China (English)

    WUYALAN; GUOHUANGFAN; 等

    1997-01-01

    Expression of opioid receptor-like receptor (ORL1) and its endogenous peptide agonist nociceptin/orphanin FQ (N/OFQ) during mouse embryogenesis have been investigated.Transcripts of ORL1 and N/OFQ were detected by RT-PCR in mouse brain of day 8 embryo (E8) and the expression continued afterwards.Northern blot analysis revealed abundant expression of ORL1 at postnatal day 1 (P1) and N/OFQ at E17 and P1 in the brain but none was detected in other embryonic tissues.The presence of functional ORL1 in mouse embryonic brain was also confirmed by specific binding of [3H]N/OFQ(kd=1.3±0.5nM and Bmax=72±9fmol/mg protein)as well as by N/OFQ-stimulated G protein activation.

  2. High-efficiency somatic embryogenesis and morphohistology and histochemistry of somatic embryo development in Larix leptolepis Gordon

    Institute of Scientific and Technical Information of China (English)

    Wang Xiao-xing; Lu Long-dou; Hao Huai-qing; Teng Nian-jun; Chen Tong; Guo Yi-ming; Yang Ying-gen; Guo Zhong-chen; Lin Jin-xing

    2007-01-01

    A high-efficiency somatic embryogenesis protocol of Japanese larch (Larix leptolepis Gordon) has been established in our investigation. Calli were induced from immature zygotic embryos of female cones ofL. leptolepis and then subcultured regularly on to a modified Gupta and Durzan (DCR) basal medium for 5 years. Embryogenic tissues showed distinct morphological changes during somatic embryo development when they were transferred to a maturation medium supplemented with abscisic acid (ABA) compared with the morphology in a medium lacking ABA. Histological observations indicated that polyembryony was a characteristic feature during early embryogeny and somatic embryos at later stages showed normal histodifferentiation. In addition, histochemical analysis revealed that abundant starch granules and proteins accumulated in mature embryos, indicating that they played important roles in the development and regeneration of normal plantlets from somatic embryos on hormone-free germination media

  3. Distribution of chicken cathepsins B and L, cystatin and ovalbumin in extra-embryonic fluids during embryogenesis.

    Science.gov (United States)

    Cirkvenčič, N; Narat, M; Dovč, P; Benčina, D

    2012-01-01

    1. Concentrations of chicken cathepsin B, cathepsin L, cystatin and ovalbumin were determined in the allantoic fluid, amniotic fluid and extracts of chorioallantoic membranes during days 6 to 12 of embryogenesis. 2. Similar trends for cystatin and ovalbumin were observed in the allantoic fluid with maximum concentrations of cystatin on day 7 (12 ± 4 µg/ml) and ovalbumin on day 8 (∼19 ± 2.5 µg/ml) of embryonic development. The highest concentrations of cathepsin B was found on day 7 and of cathepsin L on day 10, but were significantly lower than those of cystatin and ovalbumin. 3. In the allantoic fluid, especially on day 7, considerable proportions of cystatin and ovalbumin were phosphorylated and contained phosphorylated serine. 4. Concentrations of cathepsin B and L, cystatin and ovalbumin in the amniotic fluid were variable but were comparable to those in allantoic fluid.

  4. Control of developmental networks by Rac/Rho small GTPases: How cytoskeletal changes during embryogenesis are orchestrated.

    Science.gov (United States)

    Sáenz-Narciso, Beatriz; Gómez-Orte, Eva; Zheleva, Angelina; Gastaca, Irene; Cabello, Juan

    2016-12-01

    Small GTPases in the Rho family act as major nodes with functions beyond cytoskeletal rearrangements shaping the Caenorhabditis elegans embryo during development. These small GTPases are key signal transducers that integrate diverse developmental signals to produce a coordinated response in the cell. In C. elegans, the best studied members of these highly conserved Rho family small GTPases, RHO-1/RhoA, CED-10/Rac, and CDC-42, are crucial in several cellular processes dealing with cytoskeletal reorganization. In this review, we update the functions described for the Rho family small GTPases in spindle orientation and cell division, engulfment, and cellular movements during C. elegans embryogenesis, focusing on the Rho subfamily Rac. Please also see the video abstract here. © 2016 The Authors BioEssays Published by WILEY Periodicals, Inc.

  5. Vegetative propagation of Quercus suber L. by somatic embryogenesis. II. Plant regeneration from selected cork oak trees.

    Science.gov (United States)

    Hernández, I; Celestino, C; Alegre, J; Toribio, M

    2003-04-01

    The regeneration of somatic seedlings from selected 100-year-old cork oak trees is reported. The induction of somatic embryogenesis from leaves of epicormic shoots was significantly affected by genotype, harvesting time and their interaction. Leaves from all five selected trees produced somatic embryos when the segments of branches used as sources of epicormic shoots were collected in May. Genotype, but not the level of photosynthetically active radiation, affected the proliferation of the embryogenic lines and the number of detachable embryos that could be obtained from them. Genotype also affected several steps leading to conversion of somatic embryos, from germination to complete acclimatisation of somatic seedlings. Almost 40% of the somatic embryos from all lines germinated, showing coordinated root and shoot growth. Although the mean percentage of recovery for the whole process was low, plants could be regenerated from four of the five trees tested.

  6. Somatic embryogenesis and plant regeneration from cell suspension and tissue cultures of mature himalayan poplar (Populus ciliata).

    Science.gov (United States)

    Cheema, G S

    1989-02-01

    Somatic embryogenesis and plantlet formation were obtained from callus and cell suspension cultures of 40-year- old Himalayan Poplar (Populus ciliata Wall ex Royle). Callus and cell suspensions were obtained by transfer of inoculum of semiorganized leaf cultures, which were maintained on Murashige and Skoog (MS) medium supplemented with benzylaminopurine (BAP), to MS with 2,4-dichlorophenoxyacetic acid (2,4-D). Reduction of 2,4-D concentration during subsequent subculture of cell suspensions resulted in the formation of embryoids. These embryoids developed further only after being transferred to agar-based MS medium supplemented with BAP and naphthalene acetic acid. Loss of embryogenic potential was observed in cell suspensions after 6 subcultures. However, callus cultures retained the embryogenic potential even after repeated subcultures for more than a year. Plantlets could be successfully hardened and grown in natural outdoor conditions.

  7. Effect of thermal manipulation during embryogenesis on liver heat shock protein expression in chronic heat stressed colored broiler chickens.

    Science.gov (United States)

    Vinoth, A; Thirunalasundari, T; Tharian, Jenny Anne; Shanmugam, M; Rajkumar, U

    2015-10-01

    Thermal manipulation during embryogenesis has been shown to improve thermo tolerance in broilers. Heat shock proteins are a family of proteins produced in response to variety of stress and protect cells from damage. The aim of this study was to evaluate the effect of thermal manipulation (TM) during embryogenesis on HSP gene and protein expression in the embryos and in chronic heat stressed 42nd day old chicks. On 15th day of incubation, fertile eggs from two breeds-Naked neck (NN) and Punjab Broiler-2 (PB-2) were randomly divided in to two groups, namely Control (C) eggs were incubated under standard incubation conditions and Thermal Conditioning (TC) eggs were exposed to higher incubation temperature (40.5°C) for 3h on 15th, 16th and 17th day of incubation. The chicks so obtained from each group were further subdivided and reared from 15th-42nd day as normal (N; 25±1°C, 70% RH) and heat exposed (HE; 35±1°C, 50% RH) resulting in four treatment groups (CN, CHE, TCN and TCHE). Embryos of two groups (C and TC) on 17th day and birds from four treatment groups on 42nd day were sacrificed. Liver was collected for analysis of gene expression by real-time PCR and protein expression by Western blot of Heat Shock Proteins (HSP 90 alpha, HSP 90 beta, HSP 70, HSP 60, HSP 27 and ubiquitin). The plasma collected on 42nd day was analyzed for biochemical parameters. Thermal challenging of embryos of both the breeds caused significant (P≤0.05) increase in all the HSPs gene and protein expression. The TCHE chicks had significantly (P≤0.05) lower HSPs gene and protein expressions and oxidative stress compared to CHE groups in both NN and PB-2. Based on these findings it can be concluded that TM during incubation provides adaptation to broiler chicks during chronic heat stress.

  8. Early embryogenesis-specific expression of the rice transposon Ping enhances amplification of the MITE mPing.

    Directory of Open Access Journals (Sweden)

    Shota Teramoto

    2014-06-01

    Full Text Available Miniature inverted-repeat transposable elements (MITEs are numerically predominant transposable elements in the rice genome, and their activities have influenced the evolution of genes. Very little is known about how MITEs can rapidly amplify to thousands in the genome. The rice MITE mPing is quiescent in most cultivars under natural growth conditions, although it is activated by various stresses, such as tissue culture, gamma-ray irradiation, and high hydrostatic pressure. Exceptionally in the temperate japonica rice strain EG4 (cultivar Gimbozu, mPing has reached over 1000 copies in the genome, and is amplifying owing to its active transposition even under natural growth conditions. Being the only active MITE, mPing in EG4 is an appropriate material to study how MITEs amplify in the genome. Here, we provide important findings regarding the transposition and amplification of mPing in EG4. Transposon display of mPing using various tissues of a single EG4 plant revealed that most de novo mPing insertions arise in embryogenesis during the period from 3 to 5 days after pollination (DAP, and a large majority of these insertions are transmissible to the next generation. Locus-specific PCR showed that mPing excisions and insertions arose at the same time (3 to 5 DAP. Moreover, expression analysis and in situ hybridization analysis revealed that Ping, an autonomous partner for mPing, was markedly up-regulated in the 3 DAP embryo of EG4, whereas such up-regulation of Ping was not observed in the mPing-inactive cultivar Nipponbare. These results demonstrate that the early embryogenesis-specific expression of Ping is responsible for the successful amplification of mPing in EG4. This study helps not only to elucidate the whole mechanism of mPing amplification but also to further understand the contribution of MITEs to genome evolution.

  9. Timing of Tissue-specific Cell Division Requires a Differential Onset of Zygotic Transcription during Metazoan Embryogenesis.

    Science.gov (United States)

    Wong, Ming-Kin; Guan, Daogang; Ng, Kaoru Hon Chun; Ho, Vincy Wing Sze; An, Xiaomeng; Li, Runsheng; Ren, Xiaoliang; Zhao, Zhongying

    2016-06-10

    Metazoan development demands not only precise cell fate differentiation but also accurate timing of cell division to ensure proper development. How cell divisions are temporally coordinated during development is poorly understood. Caenorhabditis elegans embryogenesis provides an excellent opportunity to study this coordination due to its invariant development and widespread division asynchronies. One of the most pronounced asynchronies is a significant delay of cell division in two endoderm progenitor cells, Ea and Ep, hereafter referred to as E2, relative to its cousins that mainly develop into mesoderm organs and tissues. To unravel the genetic control over the endoderm-specific E2 division timing, a total of 822 essential and conserved genes were knocked down using RNAi followed by quantification of cell cycle lengths using in toto imaging of C. elegans embryogenesis and automated lineage. Intriguingly, knockdown of numerous genes encoding the components of general transcription pathway or its regulatory factors leads to a significant reduction in the E2 cell cycle length but an increase in cell cycle length of the remaining cells, indicating a differential requirement of transcription for division timing between the two. Analysis of lineage-specific RNA-seq data demonstrates an earlier onset of transcription in endoderm than in other germ layers, the timing of which coincides with the birth of E2, supporting the notion that the endoderm-specific delay in E2 division timing demands robust zygotic transcription. The reduction in E2 cell cycle length is frequently associated with cell migration defect and gastrulation failure. The results suggest that a tissue-specific transcriptional activation is required to coordinate fate differentiation, division timing, and cell migration to ensure proper development.

  10. Small RNA and Transcriptome Sequencing Reveal a Potential miRNA-Mediated Interaction Network That Functions during Somatic Embryogenesis in Lilium pumilum DC. Fisch.

    Directory of Open Access Journals (Sweden)

    Hongmei Sun

    2017-04-01

    Full Text Available Plant somatic embryos are widely used in the fields of germplasm conservation, breeding for genetic engineering and artificial seed production. MicroRNAs (miRNAs play pivotal roles in somatic embryogenesis (SE regulation. However, their regulatory roles during various stages of SE remain unclear. In this study, six types of embryogenic samples of Lilium pumilum DC. Fisch., including organogenic callus, embryogenic callus induced for 4 weeks, embryogenic callus induced for 6 weeks, globular embryos, torpedo embryos and cotyledon embryos, were prepared for small RNA sequencing. The results revealed a total of 2,378,760 small RNA reads, among which the most common size was 24 nt. Four hundred and fifty-two known miRNAs, belonging to more than 86 families, 57 novel miRNAs and 40 miRNA*s were identified. The 86 known miRNA families were sorted according to an alignment with their homologs across 24 land plants into the following four categories: 23 highly conserved, 4 moderately conserved, 15 less conserved and 44 species-specific miRNAs. Differentially expressed known miRNAs were identified during various stages of SE. Subsequently, the expression levels of 12 differentially expressed miRNAs and 4 targets were validated using qRT-PCR. In addition, six samples were mixed in equal amounts for transcript sequencing, and the sequencing data were used as transcripts for miRNA target prediction. A total of 66,422 unigenes with an average length of 800 bp were assembled from 56,258,974 raw reads. Gene Ontology (GO and Kyoto Encyclopedia of Genes and Genomes (KEGG enrichment indicated that 38,004 and 15,497 unigenes were successfully assigned to GO terms and KEGG pathways, respectively. Among the unigenes, 2,182 transcripts were predicted to be targets for 396 known miRNAs. The potential targets of the identified miRNAs were mostly classified into the following GO terms: cell, binding and metabolic process. Enriched KEGG analysis demonstrated that

  11. 渗透调节物质及有机附加物对小麦体细胞胚发生影响的研究%Study on the Effect of Osmosis-regulating Substances and Organic Appendices on Somatic Embryogenesis in Wheat

    Institute of Scientific and Technical Information of China (English)

    孙朝霞; 侯思宇; 王玉国

    2008-01-01

    [Objective] The study aimed to reveal the effect of osmosis-regulating substances and organic appendices on somatic embryogenesis in wheat. [Method] The suitable concentration combination of appendices was optimized by adding different concentrations of osmosis-regulating substances including mannitol, sorbitol and organic appendices such as Gln, CH and LH, into the somatic embryogenesis in wheat. [Result] The mannitol or sorbitol lower than 40 g/L was helpful for improving somatic embryogenesis; there was no significant difference in the induction rate of somatic embryogenesis when 300-500 mg/L Gln、CH or LH was respectively added into the induced medium, while somatic embryogenesis could be enhanced dramatically in the presence of 500 mg/L Gln together with 300 mg/L CH. [Conclusion] Somatic embryogenesis could be improved to some extent by different concentrations of osmosis-regulating substances and organic appendices, which laid foundation for establishing a more perfect system of somatic embryogenesis in wheat.

  12. Vaginal bleeding in late pregnancy

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000627.htm Vaginal bleeding in late pregnancy To use the sharing features ... the blood from soaking your clothes. What Causes Bleeding Later in Pregnancy? When labor begins, the cervix ...

  13. Late and chronic Lyme disease.

    Science.gov (United States)

    Donta, Sam T

    2002-03-01

    This article reviews the late and chronic manifestations of Lyme disease. Special attention is given to the chronic manifestations of the disease, detailing its pathogenesis, clinical spectrum, and laboratory criteria for the diagnosis. Based on experimental evidence and experience, approaches to the successful treatment of the late and chronic disease are outlined. Much additional work is needed to improve the understanding of the underlying pathophysiology of the disease, its diagnosis and treatment.

  14. Late prematurity: a systematic review

    Directory of Open Access Journals (Sweden)

    Luís Carlos Machado Júnior

    2014-06-01

    Full Text Available Objective: this study aimed to review the literature regarding late preterm births (34 weeks to 36 weeks and 6 days of gestation in its several aspects. Sources: the MEDLINE, LILACS, and Cochrane Library databases were searched, and the references of the articles retrieved were also used, with no limit of time. Data synthesis: numerous studies showed a recent increase in late preterm births. In all series, late preterm comprised the majority of preterm births. Studies including millions of births showed a strong association between late preterm birth and neonatal mortality. A higher mortality in childhood and among young adults was also observed. Many studies found an association with several neonatal complications, and also with long-term disorders and sequelae: breastfeeding problems, cerebral palsy, asthma in childhood, poor school performance, schizophrenia, and young adult diabetes. Some authors propose strategies to reduce late preterm birth, or to improve neonatal outcome: use of antenatal corticosteroids, changes in some of the guidelines for early delivery in high-risk pregnancies, and changes in neonatal care for this group. Conclusions: numerous studies show greater mortality and morbidity in late preterm infants compared with term infants, in addition to long-term disorders. More recent studies evaluated strategies to improve the outcomes of these neonates. Further studies on these strategies are needed.

  15. Late prematurity: a systematic review.

    Science.gov (United States)

    Machado Júnior, Luís Carlos; Passini Júnior, Renato; Rodrigues Machado Rosa, Izilda

    2014-01-01

    this study aimed to review the literature regarding late preterm births (34 weeks to 36 weeks and 6 days of gestation) in its several aspects. the MEDLINE, LILACS, and Cochrane Library databases were searched, and the references of the articles retrieved were also used, with no limit of time. numerous studies showed a recent increase in late preterm births. In all series, late preterm comprised the majority of preterm births. Studies including millions of births showed a strong association between late preterm birth and neonatal mortality. A higher mortality in childhood and among young adults was also observed. Many studies found an association with several neonatal complications, and also with long-term disorders and sequelae: breastfeeding problems, cerebral palsy, asthma in childhood, poor school performance, schizophrenia, and young adult diabetes. Some authors propose strategies to reduce late preterm birth, or to improve neonatal outcome: use of antenatal corticosteroids, changes in some of the guidelines for early delivery in high-risk pregnancies, and changes in neonatal care for this group. numerous studies show greater mortality and morbidity in late preterm infants compared with term infants, in addition to long-term disorders. More recent studies evaluated strategies to improve the outcomes of these neonates. Further studies on these strategies are needed. Copyright © 2014 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

  16. Late effects from hadron therapy

    Energy Technology Data Exchange (ETDEWEB)

    Blakely, Eleanor A.; Chang, Polly Y.

    2004-06-01

    Successful cancer patient survival and local tumor control from hadron radiotherapy warrant a discussion of potential secondary late effects from the radiation. The study of late-appearing clinical effects from particle beams of protons, carbon, or heavier ions is a relatively new field with few data. However, new clinical information is available from pioneer hadron radiotherapy programs in the USA, Japan, Germany and Switzerland. This paper will review available data on late tissue effects from particle radiation exposures, and discuss its importance to the future of hadron therapy. Potential late radiation effects are associated with irradiated normal tissue volumes at risk that in many cases can be reduced with hadron therapy. However, normal tissues present within hadron treatment volumes can demonstrate enhanced responses compared to conventional modes of therapy. Late endpoints of concern include induction of secondary cancers, cataract, fibrosis, neurodegeneration, vascular damage, and immunological, endocrine and hereditary effects. Low-dose tissue effects at tumor margins need further study, and there is need for more acute molecular studies underlying late effects of hadron therapy.

  17. Late effects from hadron therapy.

    Science.gov (United States)

    Blakely, Eleanor A; Chang, Polly Y

    2004-12-01

    Successful cancer patient survival and local tumor control from hadron radiotherapy warrant a discussion of potential secondary late effects from the radiation. The study of late-appearing clinical effects from particle beams of protons, carbon, or heavier ions is a relatively new field with few data. However, new clinical information is available from pioneer hadron radiotherapy programs in the USA, Japan, Germany and Switzerland. This paper will review available data on late tissue effects from particle radiation exposures, and discuss its importance to the future of hadron therapy. Potential late radiation effects are associated with irradiated normal tissue volumes at risk that in many cases can be reduced with hadron therapy. However, normal tissues present within hadron treatment volumes can demonstrate enhanced responses compared to conventional modes of therapy. Late endpoints of concern include induction of secondary cancers, cataract, fibrosis, neurodegeneration, vascular damage, and immunological, endocrine and hereditary effects. Low-dose tissue effects at tumor margins need further study, and there is need for more acute molecular studies underlying late effects of hadron therapy.

  18. Endogenous target mimics down-regulate miR160 mediation of ARF10, -16 and -17 cleavage during somatic embryogenesis in Dimocarpus longan Lour.

    Directory of Open Access Journals (Sweden)

    yuling elin

    2015-11-01

    Full Text Available MicroRNA160 plays a critical role in plant development by negatively regulating the auxin response factors ARF10, -16 and -17. However, the ways in which miR160 expression is regulated at the transcriptional level, and how miR160 interacts with its targets during plant embryo development, remain unknown. Here, we studied the regulatory relationships among endogenous target mimics (eTMs, and miR160 and its targets, and their involvement in hormone signaling and somatic embryogenesis (SE in Dimocarpus longan. We identified miR160 family members and isolated the miR160 precursor, primary transcript, and promoter. The promoter contained cis-acting elements responsive to stimuli such as light, abscisic acid, salicylic acid and heat stress. The pri-miR160 was down-regulated in response to salicylic acid but up-regulated by gibberellic acid, ethylene, and methyl jasmonate treatment, suggesting that pri-miR160 was associated with hormone transduction. Dlo-miR160a, -a* and -d* reached expression peaks in torpedo-shaped embryos, globular embryos and cotyledonary embryos, respectively, but were barely detectable in embryogenic callus. This suggests that they have expression-related and functional diversity, especially during the middle and later developmental stages of SE. Four potential eTMs for miR160 were identified. Two of them, glucan endo-1,3-beta- glucosidase-like protein 2-like and calpain-type cysteine protease DEK1, were confirmed to control the corresponding dlo-miR160a* expression level. This suggests that they may function to abolish the binding between dlo-miR160a* and its targets. These two eTMs also participated in auxin and ABA signal transduction. DlARF10, -16, and -17 targeting by dlo-miR160a was confirmed; their expression levels were higher in friable-embryogenic callus and incomplete compact pro-embryogenic cultures and responded to 2,4-D, suggesting they may play a major role in the early stages of longan SE dependent on 2,4-D. The e

  19. Genome-wide assessment of differential effector gene use in embryogenesis.

    Science.gov (United States)

    Barsi, Julius C; Tu, Qiang; Calestani, Cristina; Davidson, Eric H

    2015-11-15

    Six different populations of cells were isolated by fluorescence-activated cell sorting from disaggregated late blastula- and gastrula-stage sea urchin embryos according to the regulatory states expressed in these cells, as reported by recombineered bacterial artificial chromosomes producing fluorochromes. Transcriptomes recovered from these embryonic cell populations revealed striking, early differential expression of large cohorts of effector genes. The six cell populations were presumptive pigment cells, presumptive neurogenic cells, presumptive skeletogenic cells, cells from the stomodeal region of the oral ectoderm, ciliated band cells and cells from the endoderm/ectoderm boundary that will give rise both to hindgut and to border ectoderm. Transcriptome analysis revealed that each of these domains specifically expressed several hundred effector genes at significant levels. Annotation indicated the qualitative individuality of the functional nature of each cell population, even though they were isolated from embryos only 1-2 days old. In no case was more than a tiny fraction of the transcripts enriched in one population also enriched in any other of the six populations studied. As was particularly clear in the cases of the presumptive pigment, neurogenic and skeletogenic cells, all three of which represent precociously differentiating cell types of this embryo, most specifically expressed genes of given cell types are not significantly expressed at all in the other cell types. Thus, at the effector gene level, a dramatic, cell type-specific pattern of differential gene regulation is established well before any significant embryonic morphogenesis has occurred.

  20. Valproate-induced teratogenesis in Japanese rice fish (Oryzias latipes) embryogenesis.

    Science.gov (United States)

    Wu, Mengmeng; Khan, Ikhlas A; Dasmahapatra, Asok K

    2012-04-01

    Fertilized eggs of Japanese rice fish (medaka) at three developmental stages (Iwamatsu stages 4-30) were exposed to waterborne valproic acid (VPA) (0-80 mM) in hatching solution for 48 h. The amount of valproate to cause 50% mortality (IC(50)) is found to be developmental stage-specific. The embryos were more sensitive to valproate at early stages of development (Iwamatsu stages 4-10) than in the embryos in late stages (Iwamatsu stages 17-30). Valproate exposed embryos have microcephaly and disrupted cardiovasculature with delayed vessel circulation, thrombus formation, and slow heart rate. The hatching efficiency is also reduced by valproate exposure due to developmental delay. The mRNA analysis of nine genes belong to oxidative stress (catalase, gsr, gst), neurogenesis (iro3, wnt1, shh, otx2, nlgn3b) and cell cycle regulation (ccna2) have been done. It was observed that the genes belong to oxidative stress remained unaltered after valproate exposure. However, some of the genes belong to neurogenesis (wnt1,shh, otx2 and nlgn3b) and cell cycle (ccna2) showed developmental stage-specific alteration after valproate exposure. This study indicates that valproate is able to induce some of the phenotypic features which are analogous to human fetal valproate syndrome (FVS). Modulation of genes expressed in neural tissues indicates that this fish can be used to analyze the mechanisms of many neurobehavioral disorders like Autism spectrum disorder (ASD) in human.

  1. Plant regeneration from proroplasts of alfalfa (Medicago sativa) via somatic embryogenesis Regeneração de plantas a partir de protoplastos de alfafa (Medicago sativa) via embriogênese somática

    OpenAIRE

    Mariza Monteiro; Beatriz Appezzato-da-Glória; Maria José Valarini; Carlos Alberto de Oliveira; Maria Lucia Carneiro Vieira

    2003-01-01

    Alfalfa is one of the most frequently studied species from the production of tissue culture-derived embryos point of view. In this study, five alfalfa cultivars were analyzed with reference to their ability to regenerate plants from protoplast cultures via somatic embryogenesis. Plant regeneration from leaf-derived protoplasts isolated from the cultivar Rangelander was achieved using a protocol defined for alfalfa cell suspension-derived embryogenesis. Because of its high efficiency, this pro...

  2. Effect of plant growth regulators on direct somatic embryogenesis in camphor tree (Cinnamomum camphora L. ) from immature zygotic embryos and embryogenic calli induction

    Institute of Scientific and Technical Information of China (English)

    DuLi; Zhou Suo; Bao Man-zhu

    2007-01-01

    A description of a successful direct somatic embryogenesis induction from immature zygotic embryos of a camphor tree (Cinnamomum camphora L. ) is presented. After a subculture of 2-3 years,embryogenic calli could be derived from primary somaticembryos. Immature zygotic embryos were cultured on a Murashige and Skoog (MS)basal medium supplemented with a range of combinations of cytokinins (BA) and auxins(2,4-D or NAA) for somatic embryo induction. Primary somatic embryos could be induced direly in almost all PGR combinations. A positive effect of 2,4-D On somatic embryo genesis from immature zygotic embryos of camphor tree was obtained. BA at appropriate concentrations (5mg·L-1) of BA had the effect of restraining somatic embryo induction. NAA had a less positive effect on somatic embryogenesis than 2,4-D.

  3. Thermal Manipulation during Embryogenesis Has Long-Term Effects on Muscle and Liver Metabolism in Fast-Growing Chickens

    Science.gov (United States)

    Loyau, Thomas; Métayer-Coustard, Sonia; Berri, Cécile; Crochet, Sabine; Cailleau-Audouin, Estelle; Sannier, Mélanie; Chartrin, Pascal; Praud, Christophe; Hennequet-Antier, Christelle; Rideau, Nicole; Couroussé, Nathalie; Mignon-Grasteau, Sandrine; Everaert, Nadia; Duclos, Michel Jacques; Yahav, Shlomo; Tesseraud, Sophie; Collin, Anne

    2014-01-01

    Fast-growing chickens have a limited ability to tolerate high temperatures. Thermal manipulation during embryogenesis (TM) has previously been shown to lower chicken body temperature (Tb) at hatching and to improve thermotolerance until market age, possibly resulting from changes in metabolic regulation. The aim of this study was to evaluate the long-term effects of TM (12 h/d, 39.5°C, 65% RH from d 7 to 16 of embryogenesis vs. 37.8°C, 56% RH continuously) and of a subsequent heat challenge (32°C for 5 h at 34 d) on the mRNA expression of metabolic genes and cell signaling in the Pectoralis major muscle and the liver. Gene expression was analyzed by RT-qPCR in 8 chickens per treatment, characterized by low Tb in the TM groups and high Tb in the control groups. Data were analyzed using the general linear model of SAS considering TM and heat challenge within TM as main effects. TM had significant long-term effects on thyroid hormone metabolism by decreasing the muscle mRNA expression of deiodinase DIO3. Under standard rearing conditions, the expression of several genes involved in the regulation of energy metabolism, such as transcription factor PGC-1α, was affected by TM in the muscle, whereas for other genes regulating mitochondrial function and muscle growth, TM seemed to mitigate the decrease induced by the heat challenge. TM increased DIO2 mRNA expression in the liver (only at 21°C) and reduced the citrate synthase activity involved in the Krebs cycle. The phosphorylation level of p38 Mitogen-activated-protein kinase regulating the cell stress response was higher in the muscle of TM groups compared to controls. In conclusion, markers of energy utilization and growth were either changed by TM in the Pectoralis major muscle and the liver by thermal manipulation during incubation as a possible long-term adaptation limiting energy metabolism, or mitigated during heat challenge. PMID:25180913

  4. Thermal manipulation during embryogenesis has long-term effects on muscle and liver metabolism in fast-growing chickens.

    Directory of Open Access Journals (Sweden)

    Thomas Loyau

    Full Text Available Fast-growing chickens have a limited ability to tolerate high temperatures. Thermal manipulation during embryogenesis (TM has previously been shown to lower chicken body temperature (Tb at hatching and to improve thermotolerance until market age, possibly resulting from changes in metabolic regulation. The aim of this study was to evaluate the long-term effects of TM (12 h/d, 39.5°C, 65% RH from d 7 to 16 of embryogenesis vs. 37.8°C, 56% RH continuously and of a subsequent heat challenge (32°C for 5 h at 34 d on the mRNA expression of metabolic genes and cell signaling in the Pectoralis major muscle and the liver. Gene expression was analyzed by RT-qPCR in 8 chickens per treatment, characterized by low Tb in the TM groups and high Tb in the control groups. Data were analyzed using the general linear model of SAS considering TM and heat challenge within TM as main effects. TM had significant long-term effects on thyroid hormone metabolism by decreasing the muscle mRNA expression of deiodinase DIO3. Under standard rearing conditions, the expression of several genes involved in the regulation of energy metabolism, such as transcription factor PGC-1α, was affected by TM in the muscle, whereas for other genes regulating mitochondrial function and muscle growth, TM seemed to mitigate the decrease induced by the heat challenge. TM increased DIO2 mRNA expression in the liver (only at 21°C and reduced the citrate synthase activity involved in the Krebs cycle. The phosphorylation level of p38 Mitogen-activated-protein kinase regulating the cell stress response was higher in the muscle of TM groups compared to controls. In conclusion, markers of energy utilization and growth were either changed by TM in the Pectoralis major muscle and the liver by thermal manipulation during incubation as a possible long-term adaptation limiting energy metabolism, or mitigated during heat challenge.

  5. Xenopus FRS2 is involved in early embryogenesis in cooperation with the Src family kinase Laloo

    OpenAIRE

    Kusakabe, Morioh; Masuyama, Norihisa; Hanafusa, Hiroshi; Nishida, Eisuke

    2001-01-01

    FRS2 has been identified in mammalian cells as a protein that is tyrosine phosphorylated and binds to Grb2 and Shp2 in response to fibroblast growth factor (FGF) or nerve growth factor (NGF) stimulation. But neither its existence in other vertebrate classes or invertebrates nor its function during embryonic development has been defined. Here we have identified and characterized a Xenopus homolog of FRS2 (xFRS2). xFRS2 is tyrosine phosphorylated in early embryos, and overexpression of an unpho...

  6. Phenotypic variability in the field of Saccharum spp. hybrid cv. ‘C87-51’plants regenerated via somatic embryogenesis

    Directory of Open Access Journals (Sweden)

    Marisol Freire-Seijo

    2016-10-01

    Full Text Available Sugarcane (Saccharum spp. is a crop of great economic importance that has been propagated by tissue culture through organogenesis and somatic embryogenesis. The present research had as objective to determine the phenotypic variability in the field of sugar cane cv. 'C87-51' plants obtained by somatic embryogenesis in liquid culture media. Plants regenerated from somatic embryos were planted in the field next to plants propagated via organogenesis and from cuttings that were used as control. The evaluations were carried out seven months after planting in cane plant and first shoot and the variables evaluated were stem height, stem diameter, number of stems per seedlings, number of active leaves per stem and Brix. Besides, morphological characteristics were described. Plants out of type were not found in the evaluated populations. The results demonstrated that the plant regeneration pathway significantly influences the development of plants under field conditions. The propagation of sugarcane plants cv. 'C87-51' by somatic embryogenesis in liquid culture medium only induces phenotypic changes in field associated with in vitro rejuvenation similar to those previously reported for plants obtained by organogenesis. Therefore, it can be used as a method of mass propagation of plants.   Keywords: bioreactor, somatic embryos, somaclonal variation, sugarcane

  7. Developmental regulation of neuroligin genes in Japanese ricefish (Oryzias latipes) embryogenesis maintains the rhythm during ethanol-induced fetal alcohol spectrum disorder.

    Science.gov (United States)

    Haron, Mona H; Khan, Ikhlas A; Dasmahapatra, Asok K

    2014-01-01

    Although prenatal alcohol exposure is the potential cause of fetal alcohol spectrum disorder (FASD) in humans, the molecular mechanism(s) of FASD is yet unknown. We have used Japanese ricefish (Oryzias latipes) embryogenesis as an animal model of FASD and reported that this model has effectively generated several phenotypic features in the cardiovasculature and neurocranial cartilages by developmental ethanol exposure which is analogous to human FASD phenotypes. As FASD is a neurobehavioral disorder, we are searching for a molecular target of ethanol that alters neurological functions. In this communication, we have focused on neuroligin genes (nlgn) which are known to be active at the postsynaptic side of both excitatory and inhibitory synapses of the central nervous system. There are six human NLGN homologs of Japanese ricefish reported in public data bases. We have partially cloned these genes and analyzed their expression pattern during normal development and also after exposing the embryos to ethanol. Our data indicate that the expression of all six nlgn genes in Japanese ricefish embryos is developmentally regulated. Although ethanol is able to induce developmental abnormalities in Japanese ricefish embryogenesis comparable to the FASD phenotypes, quantitative real-time PCR (qPCR) analysis of nlgn mRNAs indicate unresponsiveness of these genes to ethanol. We conclude that the disruption of the developmental rhythm of Japanese ricefish embryogenesis by ethanol that leads to FASD may not affect the nlgn gene expression at the message level.

  8. Late sequelae of superficial irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Hood, I.C.; Young, J.E.

    1984-10-01

    Superficial irradiation results in well recognized late sequelae including not only sclerosis and atrophy of skin and subcutaneous tissue, but also the development of benign and malignant tumors of skin and adjacent structures. The long latency between irradiation and its late effects allowed the early uncontrolled use of radiation treatment for benign conditions. The subsequent recognition of the causal relationship between tumors and previous irradiation has restricted its use to more appropriate purposes, although it is possible that it is still overused in some areas of dermatologic practice. Clinicians need to be aware of the time interval between irradiation and the development of its late sequelae, and the incidence of these sequelae. Appropriate irradiation exposure history should be a part of the evaluation of every patient.

  9. Towards industrial production of tree varieties through somatic embryogenesis and other vegetative propagation technologies

    DEFF Research Database (Denmark)

    Find, Jens Iver

    2016-01-01

    produced plants. For this reason the focus is changing towards improvement of protocols for cost effective large scale production in a commercial set up. The first elite clones have been identified from a small preliminary clonal field trial from 2007, and larger clonal field trials have been established...

  10. [Late-onset dysthymic states].

    Science.gov (United States)

    Siranchiev, M A

    2002-01-01

    Sixty patients with dysthymic states which had emerged in later age of 60-80 years were examined. Two clinical types of dysthymic states were described: anergic (20 patients) and hypothymic (40 patients). Different comorbid mental disorders--obsessive-phobic (14 cases), somatoform (10), personality deviations (20) and psycho-organic (7)--were found to be characteristic of late-onset dysthymic states. According to developmental features, late dysthymia was primary (first manifested in the elderly) and secondary (develops after several depressive episodes). In diagnostic terms, the former is considered as "dysthymia" (F34.1 ICD-10) and the latter--as "recurrent depressive disorder" (F33).

  11. A digital framework to build, visualize and analyze a gene expression atlas with cellular resolution in zebrafish early embryogenesis.

    Directory of Open Access Journals (Sweden)

    Carlos Castro-González

    2014-06-01

    Full Text Available A gene expression atlas is an essential resource to quantify and understand the multiscale processes of embryogenesis in time and space. The automated reconstruction of a prototypic 4D atlas for vertebrate early embryos, using multicolor fluorescence in situ hybridization with nuclear counterstain, requires dedicated computational strategies. To this goal, we designed an original methodological framework implemented in a software tool called Match-IT. With only minimal human supervision, our system is able to gather gene expression patterns observed in different analyzed embryos with phenotypic variability and map them onto a series of common 3D templates over time, creating a 4D atlas. This framework was used to construct an atlas composed of 6 gene expression templates from a cohort of zebrafish early embryos spanning 6 developmental stages from 4 to 6.3 hpf (hours post fertilization. They included 53 specimens, 181,415 detected cell nuclei and the segmentation of 98 gene expression patterns observed in 3D for 9 different genes. In addition, an interactive visualization software, Atlas-IT, was developed to inspect, supervise and analyze the atlas. Match-IT and Atlas-IT, including user manuals, representative datasets and video tutorials, are publicly and freely available online. We also propose computational methods and tools for the quantitative assessment of the gene expression templates at the cellular scale, with the identification, visualization and analysis of coexpression patterns, synexpression groups and their dynamics through developmental stages.

  12. Melanoma. Shall we move away from the sun and focus more on embryogenesis, body weight and longevity?

    Science.gov (United States)

    Bataille, Veronique

    2013-11-01

    There are many observations regarding the behaviour of melanoma which points away from sunshine as the main cause of this tumour. Incidence data shows that the increase is mostly seen for thin melanomas which cannot be attributed to sun exposure but increasing screening over the last 20 years. Melanoma behaves in a similar fashion all over the world regarding age of onset, gender differences and histological subtypes. An excess of naevi is the strongest risk factor for melanoma and their appearance and involution throughout life, and the differences in naevus distribution according to gender is giving us a lot of clues about melanoma biology. Melanoma like all cancers is a complex disease with the involvement of many common and low penetrance genes many of them involved in pigmentation and naevogenesis but these only explain a very small portion of melanoma susceptibility. Genes involved in melanocyte differentiation early on in embryogenesis are also becoming relevant for melanoma initiation and progression. Reduced senescence and longevity as well as body weight and energy expenditure are also relevant for melanoma susceptibility. These observations with links between melanoma and non-sun related phenotypes as well as gene discoveries should help to assess the relative contribution of genetic and environmental factors in its causation.

  13. A digital framework to build, visualize and analyze a gene expression atlas with cellular resolution in zebrafish early embryogenesis.

    Science.gov (United States)

    Castro-González, Carlos; Luengo-Oroz, Miguel A; Duloquin, Louise; Savy, Thierry; Rizzi, Barbara; Desnoulez, Sophie; Doursat, René; Kergosien, Yannick L; Ledesma-Carbayo, María J; Bourgine, Paul; Peyriéras, Nadine; Santos, Andrés

    2014-06-01

    A gene expression atlas is an essential resource to quantify and understand the multiscale processes of embryogenesis in time and space. The automated reconstruction of a prototypic 4D atlas for vertebrate early embryos, using multicolor fluorescence in situ hybridization with nuclear counterstain, requires dedicated computational strategies. To this goal, we designed an original methodological framework implemented in a software tool called Match-IT. With only minimal human supervision, our system is able to gather gene expression patterns observed in different analyzed embryos with phenotypic variability and map them onto a series of common 3D templates over time, creating a 4D atlas. This framework was used to construct an atlas composed of 6 gene expression templates from a cohort of zebrafish early embryos spanning 6 developmental stages from 4 to 6.3 hpf (hours post fertilization). They included 53 specimens, 181,415 detected cell nuclei and the segmentation of 98 gene expression patterns observed in 3D for 9 different genes. In addition, an interactive visualization software, Atlas-IT, was developed to inspect, supervise and analyze the atlas. Match-IT and Atlas-IT, including user manuals, representative datasets and video tutorials, are publicly and freely available online. We also propose computational methods and tools for the quantitative assessment of the gene expression templates at the cellular scale, with the identification, visualization and analysis of coexpression patterns, synexpression groups and their dynamics through developmental stages.

  14. Effects of different concentrations of 2,4-D and BAP on somatic embryogenesis induction in saffron (Crocus sativus L.).

    Science.gov (United States)

    Rajabpoor, Sh; Azghandi, A V; Saboora, A

    2007-11-01

    To optimize an in vitro protocol for propagation of saffron through somatic embryogenesis, effects of various concentrations of 2,4-D ( 0, 0.25, 0.5, 1, 2, 4 and 8 mg L(-1)) in combination with BAP (0, 0.25, 0.5, 1, 2, 4 and 8 mg L(-1)) were studied. Surface-sterilized corms were cut transversally into equal portions and the upper or lower parts were used separately as explants. All treatments were maintained in the darkness at 24 +/- 2 degrees C. After 70 days, the first globular embryos were observed and the number of embryos on each explant reached to its maximum 3 months after culture. Statistical analysis showed that there were significant differences between treatments regarding the number of embryos induced on each explant. The most effective treatment was 2.0 mg L(-1) 2,4-D + 1.0 mg L(-1) BAP for both types of explant (inducing 6.5 +/- 1.3 and 35.95 +/- 4.9 embryos on each explant for the upper and lower parts, respectively). The average percentages of explants showing embryogenic response were 33.3 and 93.3% for the upper and the lower part of corm tissue respectively in this treatment. Complementary studies are in progress to optimize maturation and germination stages of these somatic embryos.

  15. VHA-19 is essential in Caenorhabditis elegans oocytes for embryogenesis and is involved in trafficking in oocytes.

    Science.gov (United States)

    Knight, Alison J; Johnson, Nicholas M; Behm, Carolyn A

    2012-01-01

    There is an urgent need to develop new drugs against parasitic nematodes, which are a significant burden on human health and agriculture. Information about the function of essential nematode-specific genes provides insight to key nematode-specific processes that could be targeted with drugs. We have characterized the function of a novel, nematode-specific Caenorhabditis elegans protein, VHA-19, and show that VHA-19 is essential in the germline and, specifically, the oocytes, for the completion of embryogenesis. VHA-19 is also involved in trafficking the oocyte receptor RME-2 to the oocyte plasma membrane and is essential for osmoregulation in the embryo, probably because VHA-19 is required for proper eggshell formation via exocytosis of cortical granules or other essential components of the eggshell. VHA-19 may also have a role in cytokinesis, either directly or as an indirect effect of its role in osmoregulation. Critically, VHA-19 is expressed in the excretory cell in both larvae and adults, suggesting that it may have a role in osmoregulation in C. elegans more generally, probably in trafficking or secretion pathways. This is the first time a role for VHA-19 has been described.

  16. 3D Visualization of Developmental Toxicity of 2,4,6-Trinitrotoluene in Zebrafish Embryogenesis Using Light-Sheet Microscopy

    Directory of Open Access Journals (Sweden)

    Juneyong Eum

    2016-11-01

    Full Text Available Environmental contamination by trinitrotoluene is of global concern due to its widespread use in military ordnance and commercial explosives. Despite known long-term persistence in groundwater and soil, the toxicological profile of trinitrotoluene and other explosive wastes have not been systematically measured using in vivo biological assays. Zebrafish embryos are ideal model vertebrates for high-throughput toxicity screening and live in vivo imaging due to their small size and transparency during embryogenesis. Here, we used Single Plane Illumination Microscopy (SPIM/light sheet microscopy to assess the developmental toxicity of explosive-contaminated water in zebrafish embryos and report 2,4,6-trinitrotoluene-associated developmental abnormalities, including defects in heart formation and circulation, in 3D. Levels of apoptotic cell death were higher in the actively developing tissues of trinitrotoluene-treated embryos than controls. Live 3D imaging of heart tube development at cellular resolution by light-sheet microscopy revealed trinitrotoluene-associated cardiac toxicity, including hypoplastic heart chamber formation and cardiac looping defects, while the real time PCR (polymerase chain reaction quantitatively measured the molecular changes in the heart and blood development supporting the developmental defects at the molecular level. Identification of cellular toxicity in zebrafish using the state-of-the-art 3D imaging system could form the basis of a sensitive biosensor for environmental contaminants and be further valued by combining it with molecular analysis.

  17. Do larval traits re-evolve? Evidence from the embryogenesis of a direct-developing salamander, Plethodon cinereus.

    Science.gov (United States)

    Kerney, Ryan R; Blackburn, David C; Müller, Hendrik; Hanken, James

    2012-01-01

    Recent molecular phylogenies suggest the surprising reacquisition of posthatching metamorphosis within an otherwise direct-developing clade of lungless salamanders (family Plethodontidae). Metamorphosis was long regarded as plesiomorphic for plethodontids, yet the genus Desmognathus, which primarily includes metamorphosing species, is now nested within a much larger clade of direct-developing species. The extent to which the putative reacquisition of metamorphosis in Desmognathus represents a true evolutionary reversal is contingent upon the extent to which both larva-specific features and metamorphosis were actually lost during the evolution of direct development. In this study we analyze development of the hyobranchial skeleton, which is dramatically remodeled during salamander metamorphosis, in the direct-developing red-backed salamander, Plethodon cinereus. We find dramatic remodeling of the hyobranchial skeleton during embryogenesis in P. cinereus and the transient appearance of larva-specific cartilages. Hyobranchial development in this direct-developing plethodontid is highly similar to that in metamorphosing plethodontids (e.g., Desmognathus). The proposed reacquisition of hyobranchial metamorphosis within Desmognathus does not represent the "re-evolution" of a lost phenotype, but instead the elaboration of an existing developmental sequence. © 2011 The Author(s). Evolution © 2011 The Society for the Study of Evolution.

  18. Suitable internal control genes for qRT-PCR normalization in cotton fiber development and somatic embryogenesis

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The mechanisms of cotton fiber development and somatic embryogenesis have been explored systematically with microarray and suppression subtractive hybridization. Real-time RT-PCR provides the simultaneous measurement of gene expression in many different samples, with which the data from microarray or others can be confirmed in detail. To achieve accurate and reliable gene expression results, normalization of real-time PCR data against one or several internal control genes is required, which should not fluctuate in different tissues during various stages of development. We assessed the gene expression of 7 frequently used housekeeping genes, including 18S rRNA, Histone3, UBQ7, Actin, Cyclophilin, Gbpolyubiquitin-1 and Gbpolyubiquitin-2, in a diverse set of 21 cotton samples. For fiber developmental series the expression of all housekeeping genes had the same down tendency after 17 DPA. But the expression of the AGP gene (arabinogalactan protein) that has high expression level at the later fiber development stage was up-regulated from 15 to 27 DPA. So the relative absolute quantification should be an efficient and convenient method for the fiber developmental series. The expression of nonfiber tissues series varied not so much against the fiber developmental series. And three best control genes Histone3, UBQ7 and Gbpolyubiquitin-1 have to be used in a combinated way to get better normalization.

  19. Molecular cloning and in silico analysis of three somatic embryogenesis receptor kinase mRNA from date palm

    Directory of Open Access Journals (Sweden)

    Rekik Imen

    2013-01-01

    Full Text Available We report here the isolation and characterizations of three somatic embryogenesis receptor kinase (PhSERK genes from palm date by a rapid amplification of cDNA ends (RACE approach. PhSERKs belong to a small family of receptor kinase genes, share a conserved structure and extensive sequence homology with previously reported plant SERK genes. Sequence analysis of these genes revealed the sequence size of 11051 pb (PhSERK1, 7981 pb (PhSERK2 and 10510 pb (PhSERK3. The open reading frames of PhSERK1, PhSERK2 and PhSERK3 are 1914 pb, 1797 pb and 1719 pb respectively. PhSERKs belongs to the LRR-type cell surface RLKs, which possess a number of characteristic domains. These include an extracellular domain (EX containing a variable number of LRR units, signal pepetide (SP immediately followed by a single transmembrane domain (TM and an intracellular kinase domain. The phylogenetic tree shows that the protein PhSERK1, PhSERK2 and PhSERK3 clustered within monocots SERKs proteins groups. We also predicted the secondary and tertiary with ligand binding sites structure of the protein PhSERKs.

  20. Transcriptome Profiling Reveals Auxin and Cytokinin Regulating Somatic Embryogenesis in Different Sister Lines of Cotton Cultivar CCR124

    Institute of Scientific and Technical Information of China (English)

    Zhenzhen Xu; Chaojun Zhang; Xueyan Zhang; Chuanliang Liu; Zhixia Wu; Zuoren Yang; Kehai Zhou

    2013-01-01

    To get a broader view on the molecular mechanisms underlying somatic embryogenesis (SE) in cotton (Gossypium hirsutum L.),global analysis of cotton transcriptome dynamics during SE in different sister lines was performed using RNA-Seq.A total of 204 349 unigenes were detected by de novo assembly of the 214 977 462 Illumina reads.The quantitative reverse transcription-polymerase chain reaction (qRT-PCR) measurements were positively correlated with the RNA-Seq results for almost all the tested genes (R2 =0.841,correlation was significant at the 0.01 level).Different phytohormone (auxin and cytokinin) concentration ratios in medium and the endogenous content changes of these two phytohormones at two stages in different sister lines suggested the roles of auxin and cytokinin during cotton SE.On the basis of global gene regulation of phytohormone-related genes,numerous genes from all the differentially expressed transcripts were involved in auxin and cytokinin biosynthesis and signal transduction pathways.Analyses of differentially expressed genes that were involved in these pathways revealed the substantial changes in gene type and abundance between two sister lines.Isolation,cloning and silencing/ overexpressing the genes that revealed remarkable up-or down-expression during cotton SE were important.Furthermore,auxin and cytokinin play a primary role in SE,but potential cross-talk with each other or other factors remains unclear.

  1. Transcriptome analysis during somatic embryogenesis of the tropical monocot Elaeis guineensis: evidence for conserved gene functions in early development.

    Science.gov (United States)

    Lin, Hsiang-Chun; Morcillo, Fabienne; Dussert, Stéphane; Tranchant-Dubreuil, Christine; Tregear, James W; Tranbarger, Timothy John

    2009-05-01

    With the aim of understanding the molecular mechanisms underlying somatic embryogenesis (SE) in oil palm, we examined transcriptome changes that occur when embryogenic suspension cells are initiated to develop somatic embryos. Two reciprocal suppression subtractive hybridization (SSH) libraries were constructed from oil palm embryogenic cell suspensions: one in which embryo development was blocked by the presence of the synthetic auxin analogue 2,4-dichlorophenoxyacetic acid (2,4-D: ) in the medium (proliferation library); and another in which cells were stimulated to form embryos by the removal of 2,4-D: from the medium (initiation library). A total of 1867 Expressed Sequence Tags (ESTs) consisting of 1567 potential unigenes were assembled from the two libraries. Functional annotation indicated that 928 of the ESTs correspond to proteins that have either no similarity to sequences in public databases or are of unknown function. Gene Ontology (GO) terms assigned to the two EST populations give clues to the underlying molecular functions, biological processes and cellular components involved in the initiation of embryo development. Macroarrays were used for transcript profiling the ESTs during SE. Hierarchical cluster analysis of differential transcript accumulation revealed 4 distinct profiles containing a total of 192 statistically significant developmentally regulated transcripts. Similarities and differences between the global results obtained with in vitro systems from dicots, monocots and gymnosperms will be discussed.

  2. GAMETOPHYTIC FACTOR 1, Involved in Pre-mRNA Splicing, Is Essential for Megagametogenesis and Embryogenesis in Arabidopsis

    Institute of Scientific and Technical Information of China (English)

    Man Liu; Li Yuan; Nai-You Liu; Dong-Qiao Shi; Jie Liu; Wei-Cai Yang

    2009-01-01

    RNA biogenesis is essential and vital for accurate expression of genes. It is obvious that cells cannot continue normal metabolism when RNA splicing is interfered with. sgt13018 is such a mutant, with partial loss of function of GAMETOPHYTIC FACTOR 1 (GFA1); a gene likely involved in RNA biogenesis in Arabidopsis. The mutant is featured in the phenotype of diminished female gametophyte development at stage FG5 and is associated with the arrest of early embryo development in Arabidopsis. Bioinformatics data showed that homoiogs of gene GFA1 in yeast and human encode putative U5 snRNPspecific proteins required for pre-mRNA splicing. Furthermore, the result of yeast two-hybrid assay indicated that GFA1 physically interacted with AtBrr2 and AtPrp8, the putative U5 snRNP components, of Arabidopsis. This investigation suggests that GFA1 is involved in mRNA biogenesis through interaction with AtBrr2 and AtPrp8 and functions in megagametogeneeis and embryogenesis in plant.

  3. VHA-19 is essential in Caenorhabditis elegans oocytes for embryogenesis and is involved in trafficking in oocytes.

    Directory of Open Access Journals (Sweden)

    Alison J Knight

    Full Text Available There is an urgent need to develop new drugs against parasitic nematodes, which are a significant burden on human health and agriculture. Information about the function of essential nematode-specific genes provides insight to key nematode-specific processes that could be targeted with drugs. We have characterized the function of a novel, nematode-specific Caenorhabditis elegans protein, VHA-19, and show that VHA-19 is essential in the germline and, specifically, the oocytes, for the completion of embryogenesis. VHA-19 is also involved in trafficking the oocyte receptor RME-2 to the oocyte plasma membrane and is essential for osmoregulation in the embryo, probably because VHA-19 is required for proper eggshell formation via exocytosis of cortical granules or other essential components of the eggshell. VHA-19 may also have a role in cytokinesis, either directly or as an indirect effect of its role in osmoregulation. Critically, VHA-19 is expressed in the excretory cell in both larvae and adults, suggesting that it may have a role in osmoregulation in C. elegans more generally, probably in trafficking or secretion pathways. This is the first time a role for VHA-19 has been described.

  4. Influence of nutrient media on callus induction, somatic embryogenesis and plant regeneration in selected Turkish crocus species.

    Science.gov (United States)

    Verma, Sandeep Kumar; Das, Ashok Kumar; Cingoz, Gunce Sahin; Uslu, Emel; Gurel, Ekrem

    2016-06-01

    Callus induction, somatic embryogenesis and plant regeneration were initiated in selected five species of Turkish crocus using three diffrent explants (leaf, stem and corm) cultured on four different media (MS, GB5, LS and CHE). The highest frequencies of callus induction (100%) and shoot regeneration (70%, with 7.2 shoots/callus) were found in the crocus species Crocus oliveri ssp. Oliveri, using the MS medium containing 5% (w/v) sucrose supplemented with (4 mg/L NAA + 4 mg/L TDZ) and (2 mg/L IAA + 2 mg/L TDZ + 2 mg/L BAP). When the embryogenic calli were transferred into the four nutrient media containing (2 mg/L IAA + 2 mg/L TDZ) and 100 mg/L ABA, these further developed into cotyledonary embryos. Maximum number of somatic embryos (2.9 embryos per leaf explant, with a frequency 46.6%) was obtained in C. oliveri ssp. Oliveri. During subculture using the half strength media, cotyledonary embryos gradually developed into plantlets.

  5. Late Afternoon at Taruntius

    Science.gov (United States)

    2002-08-01

    : 462 x 400 pix - 66k] [Full-Res - JPEG: 1250 x 1082 pix - 656k] Caption : PR Photo 19b/02 is a computer-processed version of PR Photo 19a/02 , in which the lunar surface is now viewed directly "from above". Located at 46° East lunar longitude, 6° North lunar latitude, this area is viewed from the VLT at an inclined angle and the craters therefore all appear as ellipses in the NACO image. However, taking into account the direction of the line-of-sight at the time of the observation [2], this view can be "rectified" by simple image processing. The corresponding "view from above" is shown in PR Photo 19b/02 ; most of the craters in the field now appear quite round. Many different types of lunar surface formations are visible in the VLT photo. In addition to the numerous impact craters of all sizes, there are also hills and ridges of a great variety of shapes, as well as a prominent "valley" (a "Rima", or fissure) that stretches nearly 50 km through the photo in East-West direction. It has been identified on earlier photos and as it is situated inside that crater, it was given the name "Rimae Taruntius" in 1985. It is very well resolved in this photo and resembles "Rima Hadley" that was visited by the Apollo 15 astronauts in 1971, but is much smaller. The mean width is about 600 metres (12 pixels). The bottom is in the shadows and the depth is therefore unknown. It is overlapped by several smaller craters that must have been caused by impacts after this depression was formed. Measuring the length of the shadows, it is possible to infer the height of some of the formations. For instance, the shadows of the two peaks at the lower centre of the photo are about 4 km long, indicating that these formations are about 500 metres tall. The surroundings ESO PR Photo 19c/02 ESO PR Photo 19c/02 [Preview - JPEG: 482 x 400 pix - 77k] [Normal - JPEG: 964 x 800 pix - 440k] [Full-Res - JPEG: 2408 x 1998 pix - 1.6M] Caption : Where is the NACO field at the Taruntius crater located on the

  6. Expression of Gpr177, a Wnt trafficking regulator, in mouse embryogenesis

    OpenAIRE

    Yu, Hsiao-Man Ivy; Jin, Ying; Fu, Jiang; Hsu, Wei

    2010-01-01

    Wls/Evi/Srt encoding a multipass transmembrane protein has been identified as a regulator for proper sorting and secretion of Wnt in flies. We have previously demonstrated that Gpr177 is the mouse orthologue required for axis determination. Gpr177 is a transcriptional target of Wnt which is activated to assist its subcellular distribution in a feedback regulatory loop. We therefore proposed that reciprocal regulation of Wnt and Gpr177 is essential for the Wnt-dependent developmental and patho...

  7. LATE ONSET ATRIOVENTRICULAR NODAL TACHYCARDIA

    NARCIS (Netherlands)

    PENTINGA, ML; MEEDER, JG; CRIJNS, HJGM; DEMUINCK, ED; WIESFELD, ACP; LIE, KI

    AV nodal tachycardia may present at any age, but onset in late adulthood is considered uncommon. To evaluate whether onset of AV nodal tachycardias at older age is related to organic heart disease (possibly setting the stage for re-entry due to degenerative structural changes) 32 consecutive

  8. Late onset globoid cell leukodystrophy.

    Science.gov (United States)

    Grewal, R P; Petronas, N; Barton, N W

    1991-11-01

    A 29 year old male with onset of globoid cell leukodystrophy at age 14 is described. This is the first case of enzymatically confirmed globoid cell leukodystrophy with onset of symptoms after the age of ten. This patient is unique because of the late onset and slow progression and extends the clinical spectrum of globoid cell leukodystrophy.

  9. Clerical Exile in Late Antiquity

    DEFF Research Database (Denmark)

    Engberg, Jakob

    2016-01-01

    This volume results from the international research project ‘The Migration of Faith: Clerical Exile in Late Antiquity (325‒c.600)’. The project is a collaboration between the Department of History at the University of Sheffield, the Seminar für Kirchengeschichte at the University of Halle, and th...

  10. LATE ONSET ATRIOVENTRICULAR NODAL TACHYCARDIA

    NARCIS (Netherlands)

    PENTINGA, ML; MEEDER, JG; CRIJNS, HJGM; DEMUINCK, ED; WIESFELD, ACP; LIE, KI

    1993-01-01

    AV nodal tachycardia may present at any age, but onset in late adulthood is considered uncommon. To evaluate whether onset of AV nodal tachycardias at older age is related to organic heart disease (possibly setting the stage for re-entry due to degenerative structural changes) 32 consecutive patient

  11. Late onset startle induced tics

    NARCIS (Netherlands)

    Tijssen, MAJ; Brown, P; Morris, HR; Lees, A

    1999-01-01

    Three cases of late onset Gilles de la Tourette's syndrome are presented. The motor ties were mainly induced by an unexpected startling stimulus, but the startle reflex was not exaggerated. The ties developed after physical trauma or a period of undue emotional stress. Reflex ties may occur in

  12. Late onset startle induced tics

    NARCIS (Netherlands)

    Tijssen, MAJ; Brown, P; Morris, HR; Lees, A

    1999-01-01

    Three cases of late onset Gilles de la Tourette's syndrome are presented. The motor ties were mainly induced by an unexpected startling stimulus, but the startle reflex was not exaggerated. The ties developed after physical trauma or a period of undue emotional stress. Reflex ties may occur in Gille

  13. Late detection of cleft palate

    NARCIS (Netherlands)

    Hanny, K H; de Vries, I A C; Haverkamp, S J; Oomen, K P Q; Penris, W M; Eijkemans, M J C; Kon, M; Mink van der Molen, A B; Breugem, C C

    2016-01-01

    Cleft palate only (CPO) is a common congenital malformation, and most patients are diagnosed within the first weeks after birth. Late diagnosis of the cleft palate (CP) could initially result in feeding and growth impairment, and subsequently speech and hearing problems later in life. The purpose of

  14. Prospects for advanced late blight resistance breeding in potato

    Science.gov (United States)

    The potato late blight pathogen, Phytophthora infestans, is able to rapidly evolve to overcome resistance genes. The pathogen accomplishes this by secreting an arsenal of proteins, termed effectors, that function to modify host cells. Although hundreds of candidate effectors have been identified in ...

  15. Late-onset myasthenia not on the increase

    DEFF Research Database (Denmark)

    Pedersen, E G; Hallas, Jesper; Hansen, K

    2013-01-01

    BACKGROUND: An increase in late-onset myasthenia gravis (MG) has been reported. There are few large population-based studies over longer periods of time reflecting recent developments in MG incidence. METHODS: We identified a nationwide cohort of patients with incident myasthenia in Denmark in 1996...

  16. School Mobility during Childhood Predicts Psychotic Symptoms in Late Adolescence

    Science.gov (United States)

    Winsper, Catherine; Wolke, Dieter; Bryson, Alex; Thompson, Andrew; Singh, Swaran P.

    2016-01-01

    Background: Recently, school mobility was identified as a risk factor for psychotic symptoms in early adolescence. The extent to which this risk continues into late adolescence and the trajectories via which this risk manifests remain unexplored. Methods: Psychotic symptoms in 4,720 adolescents aged 18 were ascertained by trained psychologists…

  17. Financial Conflicts Facing Late-Life Remarried Alzheimer's Disease Caregivers

    Science.gov (United States)

    Sherman, Carey Wexler; Bauer, Jean W.

    2008-01-01

    This qualitative study explores financial conflicts faced by late-life remarried wives providing care for their husbands with Alzheimer's disease. Interviews with 9 women identified intergenerational secrets and tensions regarding financial and inheritance decisions. Participants' remarried spouse status, underlying family boundary ambiguities,…

  18. Late presentation of developmental dysplasia of the hip.

    LENUS (Irish Health Repository)

    Gul, R

    2012-02-03

    BACKGROUND: A neonatal screening programme for developmental dysplasia of the hip (DDH) is ongoing in Cork. Despite early screening, infants continue to present at later ages with DDH. The impact of late diagnosis is significant. Established DDH causes significant morbidity and may have major medicolegal implications. AIM: To identify the reasons for the late presentation of DDH in the presence of a screening programme. METHODS: In a retrospective study all cases of late DDH presenting from 1988 to 2000 were identified using inpatient database. RESULTS: Forty-nine cases of DDH were diagnosed. The mean age of diagnosis was 14.8 months (range 6-47). Multiple risk factors were identified in four patients only. More than one risk factor was identified in 10 patients. CONCLUSION: Despite screening, children continue to present with late DDH. In this study, only 14 patients had multiple risk factors and only four patients had more than two risk factors, highlighting the low incidence of suspicion in this patient group.

  19. Late-presenting congenital diaphragmatic hernia

    Directory of Open Access Journals (Sweden)

    Raashid Hamid

    2014-01-01

    Full Text Available Background: This study was undertaken to highlight the clinical profile, misdiagnosis, surgical treatment,and prognosis of late-presenting congenital diaphragmatic hernia (CDH cases in a tertiary level hospital. Patients and Methods: This retrospective study included all the babies and children >1 month of age with CDH who were admitted in our Hospital (Sher-i-Kashmir Institute of Medical Sciences, Srinagar, Kashmir, India during the period between January 2008 and December 2013. Babies with age <1 month were excluded from the study. Data regarding clinical profile, operative records, and follow-up was reviewed and analysed statistically. Results: A total of 20 patients were included in this study. The clinical picture ranged from respiratory distress (13 patients to non-specific gastrointestinal complaints (5 patients. In two patients, CDH was misdiagnosed as pneumothorax and had got chest tube inserted in other hospitals before referral to this tertiary care centre. In 14 patients chest, X-ray revealed the diagnosis of CDH and in remaining five patients (including the two patients with misdiagnosis further investigations were undertaken to establish the diagnosis. Age ranged from 45 days to 17 years with an average age of 58.9 months. There were 12 male and 8 female patients. In all the 20 patients, surgical procedures were undertaken with the retrieval of herniated contents from the thoracic cavity and repair of the diaphragmatic defect. There was no mortality in our series. All the 20 patients were followed-up for a period ranging from 6 months to 5 years (median 3.1 years. Conclusions: Late-presenting CDH can have diverse clinical presentation. Late diagnosis and misdiagnosis can result in significant morbidity and potential mortality if these cases are not managed properly at an appropriate stage. Outcome is favourable if these patients are expeditiously identified and surgically repaired.

  20. Expression of Gpr177, a Wnt trafficking regulator, in mouse embryogenesis.

    Science.gov (United States)

    Yu, Hsiao-Man Ivy; Jin, Ying; Fu, Jiang; Hsu, Wei

    2010-07-01

    Wls/Evi/Srt encoding a multipass transmembrane protein has been identified as a regulator for proper sorting and secretion of Wnt in flies. We have previously demonstrated that Gpr177 is the mouse ortholog required for axis determination. Gpr177 is a transcriptional target of Wnt that is activated to assist its subcellular distribution in a feedback regulatory loop. We, therefore, proposed that reciprocal regulation of Wnt and Gpr177 is essential for the Wnt-dependent developmental and pathogenic processes. Here, we examine the expression pattern of Gpr177 in mouse development. Gpr177 is expressed in a variety of tissues and cell types during organogenesis. Furthermore, Gpr177 is a glycoprotein primarily accumulating in the Golgi apparatus in signal-producing cells. The glycosylation of Gpr177 is necessary for proper transportation in the secretory pathway. Our findings suggest that the Gpr177-mediated regulation of Wnt is crucial for organogenesis in health and disease.

  1. A single homeobox gene triggers phase transition, embryogenesis and asexual reproduction.

    Science.gov (United States)

    Horst, Nelly A; Katz, Aviva; Pereman, Idan; Decker, Eva L; Ohad, Nir; Reski, Ralf

    2016-01-18

    Plants characteristically alternate between haploid gametophytic and diploid sporophytic stages. Meiosis and fertilization respectively initiate these two different ontogenies(1). Genes triggering ectopic embryo development on vegetative sporophytic tissues are well described(2,3); however, a genetic control of embryo development from gametophytic tissues remains elusive. Here, in the moss Physcomitrella patens we show that ectopic overexpression of the homeobox gene BELL1 induces embryo formation and subsequently reproductive diploid sporophytes from specific gametophytic cells without fertilization. In line with this, BELL1 loss-of-function mutants have a wild-type phenotype, except that their egg cells are bigger and unable to form embryos. Our results identify BELL1 as a master regulator for the gametophyte-to-sporophyte transition in P. patens and provide mechanistic insights into the evolution of embryos that can generate multicellular diploid sporophytes. This developmental innovation facilitated the colonization of land by plants about 500 million years ago(4) and thus shaped our current ecosystems.

  2. Norway spruce embryogenesis: changes in carbohydrate profile, structural development and response to polyethylene glycol.

    Science.gov (United States)

    Hudec, Lukáš; Konrádová, Hana; Hašková, Anna; Lipavská, Helena

    2016-05-01

    Two unrelated, geographically distinct, highly embryogenic lines of Norway spruce (Picea abies (L.) Karst.) were analysed to identify metabolic traits characteristic for lines with good yields of high-quality embryos. The results were compared with corresponding characteristics of a poorly productive line (low embryo yield, scarce high-quality embryos). The following carbohydrate profiles and spectra during maturation, desiccation and germination were identified as promising characteristics for line evaluation: a gradual decrease in total soluble carbohydrates with an increasing sucrose : hexose ratio during maturation; accumulation of raffinose family oligosaccharides resulting from desiccation and their rapid degradation at the start of germination; and a decrease in sucrose, increase in hexoses and the appearance of pinitol with proceeding germination. We propose that any deviation from this profile in an embryonic line is a symptom of inferior somatic embryo development. We further propose that a fatty acid spectrum dominated by linoleic acid (18 : 2) was a common feature of healthy spruce somatic embryos, although it was quite different from zygotic embryos mainly containing oleic acid (18 : 1). The responses of the lines to osmotic stress were evaluated based on comparison of control (without osmoticum) and polyethylene glycol (PEG)-exposed (PEG 4000) variants. Although genetically distinct, both highly embryogenic lines responded in a very similar manner, with the only difference being sensitivity to high concentrations of PEG. At an optimum PEG concentration (3.75 and 5%), which was line specific, negative effects of PEG on embryo germination were compensated for by a higher maturation efficiency so that the application of PEG at an appropriate concentration improved the yield of healthy germinants per gram of initial embryonal mass and accelerated the process. Polyethylene glycol application, however, resulted in no improvement of the poorly

  3. Midlife migraine and late-life parkinsonism

    Science.gov (United States)

    Ross, G. Webster; Sigurdsson, Sigurdur; Garcia, Melissa; Gudmundsson, Larus S.; Sveinbjörnsdóttir, Sigurlaug; Wagner, Amy K.; Gudnason, Vilmundur; Launer, Lenore J.

    2014-01-01

    Objective: In the present study, we tested the hypothesis that having migraine in middle age is related to late-life parkinsonism and a related disorder, restless legs syndrome (RLS), also known as Willis-Ekbom disease (WED). Methods: The AGES-Reykjavik cohort (born 1907–1935) has been followed since 1967. Headaches were classified based on symptoms assessed in middle age. From 2002 to 2006, 5,764 participants were reexamined to assess symptoms of parkinsonism, diagnosis of Parkinson disease (PD), family history of PD, and RLS/WED. Results: Subjects with midlife migraine, particularly migraine with aura (MA), were in later life more likely than others to report parkinsonian symptoms (odds ratio [OR]MA = 3.6 [95% CI 2.7–4.8]) and diagnosed PD (ORMA = 2.5 [95% CI 1.2–5.2]). Women with MA were more likely than others to have a parent (ORMA = 2.26 [95% CI 1.3–4.0]) or sibling (ORMA = 1.78 [95% CI 1.1–2.9]) with PD. Late-life RLS/WED was increased for headache generally. Associations were independent of cardiovascular disease and MRI-evident presumed ischemic lesions. Conclusions: These findings suggest there may be a common vulnerability to, or consequences of, migraine and multiple indicators of parkinsonism. Additional genetic and longitudinal observational studies are needed to identify candidate pathways that may account for the comorbid constellation of symptoms. PMID:25230997

  4. Modulation of DNA methylation machineries in Japanese rice fish (Oryzias latipes) embryogenesis by ethanol and 5-azacytidine.

    Science.gov (United States)

    Dasmahapatra, Asok K; Khan, Ikhlas A

    2016-01-01

    As a sequel of our investigations on the impact of epigenome in inducing fetal alcohol spectrum disorder (FASD) phenotypes in Japanese rice fish, we have investigated on several DNA methylation machinery genes including DNA methyl transferase 3ba (dnmt3ba) and methyl binding proteins (MBPs), namely, mbd1b, mbd3a, mbd3b, and mecp2 at the transcription level. Studies were made during normal development, from 0day post fertilization (dpf) to hatching, and also exposing the fertilized eggs to ethanol or a DNMT inhibitor, 5-azacytidine (5-azaC). We observed that during development, all these genes followed distinct expression patterns, generally high mRNA copies in early phases (0-1dpf) and significantly low mRNA copies prior to or after hatching. Ethanol (100-500mM, 0-2dpf) was unable to alter any of these mRNAs in 2dpf; additional four day (2-6dpf) maintenance of these embryos in ethanol-free environment, on 6dpf, was also unable to establish any significant difference in these mRNA levels in comparison with the corresponding controls. However, continuous exposure of fertilized eggs in 300mM ethanol, 0-6dpf, showed significantly high mRNA copies only in MBPs (mbd1b, mbd3a, mbd3b, mecp2). 5-azaC (2mM) on 2dpf was able to enhance only mbd3b mRNA. Removal of 5-azaC and maintenance of these embryos in clean medium, 2-6dpf, showed significantly enhanced mbd3b and mecp2 mRNAs compared to corresponding controls on 6dpf. Our studies showed that in Japanese rice fish embryogenesis both ethanol and 5-azaC have the potential to specifically modulate the developmental rhythm of DNA methylation machineries.

  5. Functional dissection of Caenorhabditis elegans CLK-2/TEL2 cell cycle defects during embryogenesis and germline development.

    Directory of Open Access Journals (Sweden)

    Sandra C Moser

    2009-04-01

    Full Text Available CLK-2/TEL2 is essential for viability from yeasts to vertebrates, but its essential functions remain ill defined. CLK-2/TEL2 was initially implicated in telomere length regulation in budding yeast, but work in Caenorhabditis elegans has uncovered a function in DNA damage response signalling. Subsequently, DNA damage signalling defects associated with CLK-2/TEL2 have been confirmed in yeast and human cells. The CLK-2/TEL2 interaction with the ATM and ATR DNA damage sensor kinases and its requirement for their stability led to the proposal that CLK-2/TEL2 mutants might phenocopy ATM and/or ATR depletion. We use C. elegans to dissect developmental and cell cycle related roles of CLK-2. Temperature sensitive (ts clk-2 mutants accumulate genomic instability and show a delay of embryonic cell cycle timing. This delay partially depends on the worm p53 homolog CEP-1 and is rescued by co-depletion of the DNA replication checkpoint proteins ATL-1 (C. elegans ATR and CHK-1. In addition, clk-2 ts mutants show a spindle orientation defect in the eight cell stages that lead to major cell fate transitions. clk-2 deletion worms progress through embryogenesis and larval development by maternal rescue but become sterile and halt germ cell cycle progression. Unlike ATL-1 depleted germ cells, clk-2-null germ cells do not accumulate DNA double-strand breaks. Rather, clk-2 mutant germ cells arrest with duplicated centrosomes but without mitotic spindles in an early prophase like stage. This germ cell cycle arrest does not depend on cep-1, the DNA replication, or the spindle checkpoint. Our analysis shows that CLK-2 depletion does not phenocopy PIKK kinase depletion. Rather, we implicate CLK-2 in multiple developmental and cell cycle related processes and show that CLK-2 and ATR have antagonising functions during early C. elegans embryonic development.

  6. Microarray analysis of siberian ginseng cyclic somatic embryogenesis culture systems provides insight into molecular mechanisms of embryogenic cell cluster generation.

    Directory of Open Access Journals (Sweden)

    Chenguang Zhou

    Full Text Available Four systems of cyclic somatic embryogenesis of Siberian ginseng (Eleutherococcus senticosus Maxim were used to study the mechanism of embryonic cell cluster generation. The first, direct somatic embryo induction (DSEI, generates secondary embryos directly from the primary somatic embryos; the second, direct embryogenic cell cluster induction (DEC, induces embryogenic cell clusters directly from somatic embryos in agar medium. Subsequently, we found that when DEC-derived somatic embryos are transferred to suspension culture or a bioreactor culture, only somatic embryos are induced, and embryogenic cell clusters cannot form. Therefore, these new lines were named DEC cultured by liquid medium (ECS and DEC cultured by bioreactor (ECB, respectively. Transmission electron microscopy showed that DEC epidermal cells contained a variety of inclusions, distinct from other lines. A cDNA library of DEC was constructed, and 1,948 gene clusters were obtained and used as probes. RNA was prepared from somatic embryos from each of the four lines and hybridized to a microarray. In DEC, 7 genes were specifically upregulated compared with the other three lines, and 4 genes were downregulated. EsXTH1 and EsPLT1, which were among the genes upregulated in DEC, were cloned using the rapid amplification of cDNA ends (RACE. Real-time quantitative PCR showed EsXTH1 was more highly expressed in DEC than in other lines throughout the culture cycle, and EsPLT1 expression in DEC increased as culture duration increased, but remained at a low expression level in other lines. These results suggest that EsXTH1 and EsPLT1 may be the essential genes that play important roles during the induction of embryogenic cell clusters.

  7. Transient exposure to ethanol during zebrafish embryogenesis results in defects in neuronal differentiation: an alternative model system to study FASD.

    Directory of Open Access Journals (Sweden)

    Xavier Joya

    Full Text Available The exposure of the human embryo to ethanol results in a spectrum of disorders involving multiple organ systems, including the impairment of the development of the central nervous system (CNS. In spite of the importance for human health, the molecular basis of prenatal ethanol exposure remains poorly understood, mainly to the difficulty of sample collection. Zebrafish is now emerging as a powerful organism for the modeling and the study of human diseases. In this work, we have assessed the sensitivity of specific subsets of neurons to ethanol exposure during embryogenesis and we have visualized the sensitive embryonic developmental periods for specific neuronal groups by the use of different transgenic zebrafish lines.In order to evaluate the teratogenic effects of acute ethanol exposure, we exposed zebrafish embryos to ethanol in a given time window and analyzed the effects in neurogenesis, neuronal differentiation and brain patterning. Zebrafish larvae exposed to ethanol displayed small eyes and/or a reduction of the body length, phenotypical features similar to the observed in children with prenatal exposure to ethanol. When neuronal populations were analyzed, we observed a clear reduction in the number of differentiated neurons in the spinal cord upon ethanol exposure. There was a decrease in the population of sensory neurons mainly due to a decrease in cell proliferation and subsequent apoptosis during neuronal differentiation, with no effect in motoneuron specification.Our investigation highlights that transient exposure to ethanol during early embryonic development affects neuronal differentiation although does not result in defects in early neurogenesis. These results establish the use of zebrafish embryos as an alternative research model to elucidate the molecular mechanism(s of ethanol-induced developmental toxicity at very early stages of embryonic development.

  8. Transient Exposure to Ethanol during Zebrafish Embryogenesis Results in Defects in Neuronal Differentiation: An Alternative Model System to Study FASD

    Science.gov (United States)

    Joya, Xavier; Garcia-Algar, Oscar; Vall, Oriol; Pujades, Cristina

    2014-01-01

    Background The exposure of the human embryo to ethanol results in a spectrum of disorders involving multiple organ systems, including the impairment of the development of the central nervous system (CNS). In spite of the importance for human health, the molecular basis of prenatal ethanol exposure remains poorly understood, mainly to the difficulty of sample collection. Zebrafish is now emerging as a powerful organism for the modeling and the study of human diseases. In this work, we have assessed the sensitivity of specific subsets of neurons to ethanol exposure during embryogenesis and we have visualized the sensitive embryonic developmental periods for specific neuronal groups by the use of different transgenic zebrafish lines. Methodology/Principal Findings In order to evaluate the teratogenic effects of acute ethanol exposure, we exposed zebrafish embryos to ethanol in a given time window and analyzed the effects in neurogenesis, neuronal differentiation and brain patterning. Zebrafish larvae exposed to ethanol displayed small eyes and/or a reduction of the body length, phenotypical features similar to the observed in children with prenatal exposure to ethanol. When neuronal populations were analyzed, we observed a clear reduction in the number of differentiated neurons in the spinal cord upon ethanol exposure. There was a decrease in the population of sensory neurons mainly due to a decrease in cell proliferation and subsequent apoptosis during neuronal differentiation, with no effect in motoneuron specification. Conclusion Our investigation highlights that transient exposure to ethanol during early embryonic development affects neuronal differentiation although does not result in defects in early neurogenesis. These results establish the use of zebrafish embryos as an alternative research model to elucidate the molecular mechanism(s) of ethanol-induced developmental toxicity at very early stages of embryonic development. PMID:25383948

  9. Carbon source dependent somatic embryogenesis and plant regeneration in cotton, Gossypium hirsutum L. cv. SVPR2 through suspension cultures.

    Science.gov (United States)

    Ganesan, M; Jayabalan, N

    2005-10-01

    Highly reproducible and simple protocol for cotton somatic embryogenesis is described here by using different concentrations of maltose, glucose, sucrose and fructose. Maltose (30 g/l) is the best carbon source for embryogenic callus induction and glucose (30 g/l) was suitable for induction, maturation of embryoids and plant regeneration. Creamy white embryogenic calli of hypocotyl explants were formed on medium containing MS basal salts, myo-inositol (100 mg/l), thiamine HCI (0.3 mg/l), picloram (0.3 mg/l), Kin (0.1 mg/l) and maltose (30 g/l). During embryo induction and maturation, accelerated growth was observed in liquid medium containing NH3NO4 (1 g/l), picloram (2.0 mg/l), 2 ip (0.2 mg/l), Kin (0.1 mg/l) and glucose (30 g/l). Before embryoid induction, large clumps of embryogenic tissue were formed. These tissues only produced viable embryoids. Completely matured somatic embryos were germinated successfully on the medium fortified with MS salts, myo-inositol (50 mg/l), thiamine HCl (0.2 mg/l), GA3 (0.2 mg/l), BA (1.0 mg/l) and glucose (30 g/l). Compared with earlier reports, 65% of somatic embryo germination was observed. The abnormal embryo formation was highly reduced by using glucose (30 g/l) compared to other carbon sources. The regenerated plantlets were fertile but smaller in height than the seed derived control plants.

  10. Late onset clozapine induced agranulocytosis

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    Rajmohan Velayudhan

    2014-01-01

    Full Text Available Agranulocytosis is defined as an absolute neutrophil count less than 100/mm 3 in association with infectious disease. The risk of agranulocytosis is 0.38% of all clozapine treated cases and there is a relatively lesser incidence in Indian population. The risk of clozapine-induced agranulocytosis and neutropenia is highest in the first 6 months and higher in the initial 18 months after the onset of treatment. There have been very few reports of neutropenia and agranulocytosis after this period. There have so far been no reports of late onset clozapine induced agranulocytosis has been reported from India. A case of late onset clozapine induced agranulocytosis with possible mechanism of the same is reported.

  11. Monomelic amyotrophy with late progression.

    Science.gov (United States)

    Rowin, J; Meriggioli, M N; Cochran, E J

    2001-04-01

    Monomelic amyotrophy is a sporadic juvenile-onset disease that presents with gradual onset of weakness and atrophy in the hand muscles unilaterally. Generally, this disease is considered a 'benign' and non-progressive motor neuron disease, which stabilizes within five years of onset. We discuss a case that illustrates that monomelic amyotrophy may rarely exhibit late clinical progression to the lower extremities after a prolonged period of disease stability.

  12. Late colonization of Easter Island.

    Science.gov (United States)

    Hunt, Terry L; Lipo, Carl P

    2006-03-17

    Easter Island (Rapa Nui) provides a model of human-induced environmental degradation. A reliable chronology is central to understanding the cultural, ecological, and demographic processes involved. Radiocarbon dates for the earliest stratigraphic layers at Anakena, Easter Island, and analysis of previous radiocarbon dates imply that the island was colonized late, about 1200 A.D. Substantial ecological impacts and major cultural investments in monumental architecture and statuary thus began soon after initial settlement.

  13. The TALE transcription factor homothorax functions to assemble heterochromatin during Drosophila embryogenesis.

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    Miguel Angel Zaballos

    Full Text Available We have previously identified Homothorax (Hth as an important factor for the correct assembly of the pericentromeric heterochromatin during the first fast syncytial divisions of the Drosophila embryo. Here we have extended our studies to later stages of embryonic development. We were able to show that hth mutants exhibit a drastic overall reduction in the tri-methylation of H3 in Lys9, with no reduction of the previous di-methylation. One phenotypic outcome of such a reduction is a genome instability visualized by the many DNA breaks observed in the mutant nuclei. Moreover, loss of Hth leads to the opening of closed heterochromatic regions, including the rDNA genomic region. Our data show that the satellite repeats get transcribed in wild type embryos and that this transcription depends on the presence of Hth, which binds to them as well as to the rDNA region. This work indicates that there is an important role of transcription of non-coding RNAs for constitutive heterochromatin assembly in the Drosophila embryo, and suggests that Hth plays an important role in this process.

  14. The TALE transcription factor homothorax functions to assemble heterochromatin during Drosophila embryogenesis.

    Science.gov (United States)

    Zaballos, Miguel Angel; Cantero, Walter; Azpiazu, Natalia

    2015-01-01

    We have previously identified Homothorax (Hth) as an important factor for the correct assembly of the pericentromeric heterochromatin during the first fast syncytial divisions of the Drosophila embryo. Here we have extended our studies to later stages of embryonic development. We were able to show that hth mutants exhibit a drastic overall reduction in the tri-methylation of H3 in Lys9, with no reduction of the previous di-methylation. One phenotypic outcome of such a reduction is a genome instability visualized by the many DNA breaks observed in the mutant nuclei. Moreover, loss of Hth leads to the opening of closed heterochromatic regions, including the rDNA genomic region. Our data show that the satellite repeats get transcribed in wild type embryos and that this transcription depends on the presence of Hth, which binds to them as well as to the rDNA region. This work indicates that there is an important role of transcription of non-coding RNAs for constitutive heterochromatin assembly in the Drosophila embryo, and suggests that Hth plays an important role in this process.

  15. PS integrins and laminins: key regulators of cell migration during Drosophila embryogenesis.

    Science.gov (United States)

    Urbano, Jose M; Domínguez-Giménez, Paloma; Estrada, Beatriz; Martín-Bermudo, María D

    2011-01-01

    During embryonic development, there are numerous cases where organ or tissue formation depends upon the migration of primordial cells. In the Drosophila embryo, the visceral mesoderm (vm) acts as a substrate for the migration of several cell populations of epithelial origin, including the endoderm, the trachea and the salivary glands. These migratory processes require both integrins and laminins. The current model is that αPS1βPS (PS1) and/or αPS3βPS (PS3) integrins are required in migrating cells, whereas αPS2βPS (PS2) integrin is required in the vm, where it performs an as yet unidentified function. Here, we show that PS1 integrins are also required for the migration over the vm of cells of mesodermal origin, the caudal visceral mesoderm (CVM). These results support a model in which PS1 might have evolved to acquire the migratory function of integrins, irrespective of the origin of the tissue. This integrin function is highly specific and its specificity resides mainly in the extracellular domain. In addition, we have identified the Laminin α1,2 trimer, as the key extracellular matrix (ECM) component regulating CVM migration. Furthermore, we show that, as it is the case in vertebrates, integrins, and specifically PS2, contributes to CVM movement by participating in the correct assembly of the ECM that serves as tracks for migration.

  16. Restoration of normal embryogenesis by mitochondrial supplementation in pig oocytes exhibiting mitochondrial DNA deficiency.

    Science.gov (United States)

    Cagnone, Gael L M; Tsai, Te-Sha; Makanji, Yogeshwar; Matthews, Pamela; Gould, Jodee; Bonkowski, Michael S; Elgass, Kirstin D; Wong, Ashley S A; Wu, Lindsay E; McKenzie, Matthew; Sinclair, David A; St John, Justin C

    2016-03-18

    An increasing number of women fail to achieve pregnancy due to either failed fertilization or embryo arrest during preimplantation development. This often results from decreased oocyte quality. Indeed, reduced mitochondrial DNA copy number (mitochondrial DNA deficiency) may disrupt oocyte quality in some women. To overcome mitochondrial DNA deficiency, whilst maintaining genetic identity, we supplemented pig oocytes selected for mitochondrial DNA deficiency, reduced cytoplasmic maturation and lower developmental competence, with autologous populations of mitochondrial isolate at fertilization. Supplementation increased development to blastocyst, the final stage of preimplantation development, and promoted mitochondrial DNA replication prior to embryonic genome activation in mitochondrial DNA deficient oocytes but not in oocytes with normal levels of mitochondrial DNA. Blastocysts exhibited transcriptome profiles more closely resembling those of blastocysts from developmentally competent oocytes. Furthermore, mitochondrial supplementation reduced gene expression patterns associated with metabolic disorders that were identified in blastocysts from mitochondrial DNA deficient oocytes. These results demonstrate the importance of the oocyte's mitochondrial DNA investment in fertilization outcome and subsequent embryo development to mitochondrial DNA deficient oocytes.

  17. Hedgehog signaling regulates FOXA2 in esophageal embryogenesis and Barrett’s metaplasia

    Science.gov (United States)

    Wang, David H.; Tiwari, Anjana; Kim, Monica E.; Clemons, Nicholas J.; Regmi, Nanda L.; Hodges, William A.; Berman, David M.; Montgomery, Elizabeth A.; Watkins, D. Neil; Zhang, Xi; Zhang, Qiuyang; Jie, Chunfa; Spechler, Stuart J.; Souza, Rhonda F.

    2014-01-01

    Metaplasia can result when injury reactivates latent developmental signaling pathways that determine cell phenotype. Barrett’s esophagus is a squamous-to-columnar epithelial metaplasia caused by reflux esophagitis. Hedgehog (Hh) signaling is active in columnar-lined, embryonic esophagus and inactive in squamous-lined, adult esophagus. We showed previously that Hh signaling is reactivated in Barrett’s metaplasia and overexpression of Sonic hedgehog (SHH) in mouse esophageal squamous epithelium leads to a columnar phenotype. Here, our objective was to identify Hh target genes involved in Barrett’s pathogenesis. By microarray analysis, we found that the transcription factor Foxa2 is more highly expressed in murine embryonic esophagus compared with postnatal esophagus. Conditional activation of Shh in mouse esophageal epithelium induced FOXA2, while FOXA2 expression was reduced in Shh knockout embryos, establishing Foxa2 as an esophageal Hh target gene. Evaluation of patient samples revealed FOXA2 expression in Barrett’s metaplasia, dysplasia, and adenocarcinoma but not in esophageal squamous epithelium or squamous cell carcinoma. In esophageal squamous cell lines, Hh signaling upregulated FOXA2, which induced expression of MUC2, an intestinal mucin found in Barrett’s esophagus, and the MUC2-processing protein AGR2. Together, these data indicate that Hh signaling induces expression of genes that determine an intestinal phenotype in esophageal squamous epithelial cells and may contribute to the development of Barrett’s metaplasia. PMID:25083987

  18. PS integrins and laminins: key regulators of cell migration during Drosophila embryogenesis.

    Directory of Open Access Journals (Sweden)

    Jose M Urbano

    Full Text Available During embryonic development, there are numerous cases where organ or tissue formation depends upon the migration of primordial cells. In the Drosophila embryo, the visceral mesoderm (vm acts as a substrate for the migration of several cell populations of epithelial origin, including the endoderm, the trachea and the salivary glands. These migratory processes require both integrins and laminins. The current model is that αPS1βPS (PS1 and/or αPS3βPS (PS3 integrins are required in migrating cells, whereas αPS2βPS (PS2 integrin is required in the vm, where it performs an as yet unidentified function. Here, we show that PS1 integrins are also required for the migration over the vm of cells of mesodermal origin, the caudal visceral mesoderm (CVM. These results support a model in which PS1 might have evolved to acquire the migratory function of integrins, irrespective of the origin of the tissue. This integrin function is highly specific and its specificity resides mainly in the extracellular domain. In addition, we have identified the Laminin α1,2 trimer, as the key extracellular matrix (ECM component regulating CVM migration. Furthermore, we show that, as it is the case in vertebrates, integrins, and specifically PS2, contributes to CVM movement by participating in the correct assembly of the ECM that serves as tracks for migration.

  19. Severe malformations of eelpout (Zoarces viviparus) fry are induced by maternal estrogenic exposure during early embryogenesis.

    Science.gov (United States)

    Morthorst, Jane E; Korsgaard, Bodil; Bjerregaard, Poul

    2016-02-01

    Pregnant eelpout were exposed via the water to known endocrine disrupting compounds (EDCs) to clarify if EDCs could be causing the increased eelpout fry malformation frequencies observed in coastal areas receiving high anthropogenic input. The presence of a teratogenic window for estrogen-induced malformations was also investigated by starting the exposure at different times during eelpout pregnancy. Both 17α-ethinylestradiol (EE2) (17.8 ng/L) and pyrene (0.5 μg/L) significantly increased fry malformation frequency whereas 4-t-octylphenol (4-t-OP) up to 14.3 μg/L did not. Vitellogenin was significantly induced by EE2 (5.7 and 17.8 ng/L) but not by 4-t-OP and pyrene. A critical period for estrogen-induced fry malformations was identified and closed between 14 and 22 days post fertilization (dpf). Exposure to 17β-estradiol (E2) between 0 and 14 dpf caused severe malformations and severity increased the closer exposure start was to fertilization, whereas malformations were absent by exposure starting later than 14 dpf. Data on ovarian fluid volume and larval length supported the suggested teratogenic window. Larval mortality also increased when exposure started right after fertilization.

  20. Tissue-Specific Gain of RTK Signalling Uncovers Selective Cell Vulnerability during Embryogenesis.

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    Yannan Fan

    Full Text Available The successive events that cells experience throughout development shape their intrinsic capacity to respond and integrate RTK inputs. Cellular responses to RTKs rely on different mechanisms of regulation that establish proper levels of RTK activation, define duration of RTK action, and exert quantitative/qualitative signalling outcomes. The extent to which cells are competent to deal with fluctuations in RTK signalling is incompletely understood. Here, we employ a genetic system to enhance RTK signalling in a tissue-specific manner. The chosen RTK is the hepatocyte growth factor (HGF receptor Met, an appropriate model due to its pleiotropic requirement in distinct developmental events. Ubiquitously enhanced Met in Cre/loxP-based Rosa26(stopMet knock-in context (Del-R26(Met reveals that most tissues are capable of buffering enhanced Met-RTK signalling thus avoiding perturbation of developmental programs. Nevertheless, this ubiquitous increase of Met does compromise selected programs such as myoblast migration. Using cell-type specific Cre drivers, we genetically showed that altered myoblast migration results from ectopic Met expression in limb mesenchyme rather than in migrating myoblasts themselves. qRT-PCR analyses show that ectopic Met in limbs causes molecular changes such as downregulation in the expression levels of Notum and Syndecan4, two known regulators of morphogen gradients. Molecular and functional studies revealed that ectopic Met expression in limb mesenchyme does not alter HGF expression patterns and levels, but impairs HGF bioavailability. Together, our findings show that myoblasts, in which Met is endogenously expressed, are capable of buffering increased RTK levels, and identify mesenchymal cells as a cell type vulnerable to ectopic Met-RTK signalling. These results illustrate that embryonic cells are sensitive to alterations in the spatial distribution of RTK action, yet resilient to fluctuations in signalling levels of an