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Sample records for somatic embryogenesis induction

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

    PubMed

    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. PMID:26619869

  2. Induction of Somatic Embryogenesis Using Side Chain and Ring Modified Forms of Phenoxy Acid Growth Regulators 1

    PubMed Central

    Stuart, David A.; McCall, Carol M.

    1992-01-01

    The induction of somatic embryo development in cell cultures of alfalfa (Medicago sativa), celery (Apium graveolens), and lettuce (Lactuca sativa) was compared for 2,4-dichlorophenoxy-acetic acid (2,4-D) and various phenoxy acid growth regulators. Tests using a series of straight chain extensions to the phenoxy acid side chain indicate that phenoxybutanoic acid is active, whereas the phenoxypropanoic and phenoxypentanoic analogs are inactive for the induction of alfalfa embryogenesis. Side branching on the carbon adjacent to the phenoxy group results in optically active compounds. Racemic mixtures and the (+) enantiomers of the compounds are active for alfalfa embryo induction, whereas the (?) enantiomers are inactive and apparently do not inhibit embryogenesis in any way. Development of alfalfa embryos, as measured by plantlet formation from individual embryos, is improved by 4-(2,4-dichlorophenoxy)butanoic acid and with side branching at the carbon adjacent to the phenoxy group compared with induction with 2,4-D. Similarly, substituted phenoxy acids also enhance somatic embryo development in celery and lettuce when compared with 2,4-D. These results are discussed with reference to earlier studies on the structure activity of various synthetic auxins during cell elongation and with reference to the possible importance of auxin metabolism on subsequent somatic embryo development. PMID:16668836

  3. Dynamics of the concentration of IAA and some of its conjugates during the induction of somatic embryogenesis in Coffea canephora.

    PubMed

    Ayil-Gutiérrez, Benajmín; Galaz-Ávalos, Rosa; Peña-Cabrera, Eduardo; Loyola-Vargas, Victor

    2013-11-01

    Most of the somatic embryogenesis (SE) process requires the presence, either before or during the embryogenic process, of at least one exogenous auxin. This exogenous auxin induces the presence of endogenous auxins, which appears to be essential for SE induction. We found that during the preincubation period of SE in Coffea canephora, there is an important increase in both free and conjugated indole-3-acetic acid (IAA), as well as indole-3-butyric acid. This increase is accompanied by an increase in the expression of YUCCA (CcYUC), TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS 1 (CcTAA1), and GRETCHEN HAGEN 3 (GH3) genes. On the other hand, most of the IAA compounds decreased during the induction of SE. The results presented in this research suggest that a balance between free IAA and its amide conjugates is necessary to allow the expression of SE-related genes. PMID:24299659

  4. Somatic Embryogenesis in Pinus spp.

    PubMed

    Montalbán, Itziar Aurora; García-Mendiguren, Olatz; Moncaleán, Paloma

    2016-01-01

    Somatic embryogenesis (SE) has been the most important development for plant tissue culture, not only for mass propagation but also for enabling the implementation of biotechnological tools that can be used to increase the productivity and wood quality of plantation forestry. Development of SE in forest trees started in 1985 and nowadays many studies are focused on the optimization of conifer SE system. However, these advances for many Pinus spp. are not sufficiently refined to be implemented commercially. In this chapter, a summary of the main systems used to achieve SE in Pinus spp. is reported. PMID:26619876

  5. Induction of somatic embryogenesis in explants of shoot cultures established from adult Eucalyptus globulus and E. saligna?×?E. maidenii trees.

    PubMed

    Corredoira, E; Ballester, A; Ibarra, M; Vieitez, A M

    2015-06-01

    A reproducible procedure for induction of somatic embryogenesis (SE) from adult trees of Eucalyptus globulus Labill. and the hybrid E. saligna Smith?×?E. maidenii has been developed for the first time. Somatic embryos were obtained from both shoot apex and leaf explants of all three genotypes evaluated, although embryogenic frequencies were significantly influenced by the species/genotype, auxin and explant type. Picloram was more efficient for somatic embryo induction than naphthaleneacetic acid (NAA), with the highest frequency of induction being obtained in Murashige and Skoog medium containing 40?µM picloram and 40?mg?l(-1) gum Arabic, in which 64% of the shoot apex explants and 68.8% of the leaf explants yielded somatic embryos. The embryogenic response of the hybrid was higher than that of the E. globulus, especially when NAA was used. The cultures initiated on picloram-containing medium consisted of nodular embryogenic structures surrounded by a mucilaginous coating layer that emerged from a watery callus developed from the initial explants. Cotyledonary somatic embryos were differentiated after subculture of these nodular embryogenic structures on a medium lacking plant growth regulators. Histological analysis confirmed the bipolar organization of the somatic embryos, with shoot and root meristems and closed procambial tissue that bifurcated into small cotyledons. The root pole was more differentiated than the shoot pole, which appeared to be formed by a few meristematic layers. Maintenance of the embryogenic lines by secondary SE was attained by subculturing individual cotyledonary embryos or small clusters of globular and torpedo embryos on medium with 16.11?µM NAA at 4- to 5-week intervals. Somatic embryos converted into plantlets after being transferred to liquid germination medium although plant regeneration remained poor. PMID:25877768

  6. Somatic Embryogenesis and Genetic Modification of Vitis.

    PubMed

    Dhekney, Sadanand A; Li, Zhijian T; Grant, Trudi N L; Gray, Dennis J

    2016-01-01

    Grapevine embryogenic cultures are ideal target tissues for inserting desired traits of interest and improving existing cultivars via precision breeding (PB). PB is a new approach that, like conventional breeding, utilizes only DNA fragments obtained from sexually compatible grapevine plants. Embryogenic culture induction occurs by placing leaves or stamens and pistils on induction medium with a dark/light photoperiod cycle for 12-16 weeks. Resulting cultures produce sectors of embryogenic and non-embryogenic callus, which can be identified on the basis of callus morphology and color. Somatic embryo development occurs following transfer of embryogenic callus to development medium and cultures can be maintained for extended periods of time by transfer of the proliferating proembryonic masses to fresh medium at 4-6-week intervals. To demonstrate plant recovery via PB, somatic embryos at the mid-cotyledonary stage are cocultivated with Agrobacterium containing the desired gene of interest along with a, non-PB, enhanced green fluorescent protein/neomycin phosphotransferase II (egfp/nptII) fusion gene. Modified cultures are grown on proliferation and development medium to produce uniformly modified somatic embryos via secondary embryogenesis. Modified embryos identified on the basis of green fluorescence and kanamycin resistance are transferred to germination medium for plant development. The resulting plants are considered to prototype examples of the PB approach, since they contain egfp/nptII, a non-grapevine-derived fusion gene. Uniform green fluorescent protein (GFP) fluorescence can be observed in all tissues of regenerated plants. PMID:26619866

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

    PubMed

    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. PMID:26619874

  8. Somatic Embryogenesis in Araucaria angustifolia (Bertol.) Kuntze (Araucariaceae).

    PubMed

    Guerra, Miguel P; Steiner, Neusa; Farias-Soares, Francine L; Vieira, Leila do N; Fraga, Hugo P F; Rogge-Renner, Gladys D; Maldonado, Sara B

    2016-01-01

    This chapter deals with the features of somatic embryogenesis (SE) in Araucaria angustifolia, an endangered and native conifer from south Brazil. In this species SE includes the induction and proliferation of embryogenic cultures composed of pro-embryogenic masses (PEMs), which precede somatic embryos development. A. angustifolia SE model encompasses induction, proliferation, pre-maturation, and maturation steps. Double-staining with acetocarmine and Evan's blue is useful to evaluate the embryonic somatic structures. In this chapter we describe A. angustifolia SE protocols and analyzes morphological features in the different SE developmental stages. PMID:26619879

  9. Somatic Versus Zygotic Embryogenesis: Learning from Seeds.

    PubMed

    Winkelmann, Traud

    2016-01-01

    Plant embryogenesis is a fascinating developmental program that is very successfully established in nature in seeds. In case of in vitro somatic embryogenesis this process is subjected to several limitations such as asynchronous differentiation and further development of somatic embryos, malformations and disturbed polarity, precocious germination, lack of maturity, early loss of embryogenic potential, and strong genotypic differences in the regeneration efficiency. Several studies have shown the similarity of somatic and zygotic embryos in terms of morphological, histological, biochemical, and physiological aspects. However, pronounced differences have also been reported and refer to much higher stress levels, less accumulation of storage compounds and a missing distinction of differentiation and germination by a quiescent phase in somatic embryos. Here, an overview on recent literature describing both embryogenesis pathways, comparing somatic and zygotic embryos and analyzing the role of the endosperm is presented. By taking zygotic embryos as the reference and learning from the situation in seeds, somatic embryogenesis can be improved and optimized in order to make use of the enormous potential this regeneration pathway offers for plant propagation and breeding. PMID:26619857

  10. Somatic Embryogenesis in Crocus sativus L.

    PubMed

    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. PMID:26619871

  11. Somatic Embryogenesis in Lisianthus (Eustoma russellianum Griseb.).

    PubMed

    Ruffoni, Barbara; Bassolino, Laura

    2016-01-01

    Somatic embryogenesis is, for the main floricultural crops, a promising system for commercial scale-up, providing cloned material to be traded as seedlings.Somatic embryos, having the contemporary presence of root apical meristem and shoot apical meristem, can be readily acclimatized. For Lisianthus it is possible to induce embryogenic callus from leaf fragments of selected genotypes and to obtain embryos either in agarized substrate or in liquid suspension culture. The production of somatic embryos in liquid medium is high and can be modulated in order to synchronize the cycle and the size of the neoformed structures. The possibility to use the liquid substrate with high propagation rates reduces labor costs and could support the costs of eventual automation. In this paper we report a stepwise protocol for somatic embryogenesis in the species Eustoma russellianum. PMID:26619872

  12. Somatic embryogenesis in Hedychium bousigonianum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An efficient primary somatic embryo (SE) and secondary somatic embryo (SSE) production system was developed for the ornamental ginger Hedychium bousigonianum Pierre ex Gagnepain. Addition of two ethylene inhibitors, salicylic acid (SA) and silver nitrate (AgNO3), to the culture media improved the sy...

  13. Potential link between biotic defense activation and recalcitrance to induction of somatic embryogenesis in shoot primordia from adult trees of white spruce (Picea glauca)

    PubMed Central

    2013-01-01

    Background Among the many commercial opportunities afforded by somatic embryogenesis (SE), it is the ability to clonally propagate individual plants with rare or elite traits that has some of the most significant implications. This is particularly true for many long-lived species, such as conifers, but whose long generation times pose substantive challenges, including increased recalcitrance for SE as plants age. Identification of a clonal line of somatic embryo-derived trees whose shoot primordia have remained responsive to SE induction for over a decade, provided a unique opportunity to examine the molecular aspects underpinning SE within shoot tissues of adult white spruce trees. Results Microarray analysis was used to conduct transcriptome-wide expression profiling of shoot explants taken from this responsive genotype following one week of SE induction, which when compared with that of a nonresponsive genotype, led to the identification of four of the most differentially expressed genes within each genotype. Using absolute qPCR to expand the analysis to three weeks of induction revealed that differential expression of all eight candidate genes was maintained to the end of the induction treatment, albeit to differing degrees. Most striking was that both the magnitude and duration of candidate gene expression within the nonresponsive genotype was indicative of an intense physiological response. Examining their putative identities further revealed that all four encoded for proteins with similarity to angiosperm proteins known to play prominent roles in biotic defense, and that their high-level induction over an extended period is consistent with activation of a biotic defense response. In contrast, the more temperate response within the responsive genotype, including induction of a conifer-specific dehydrin, is more consistent with elicitation of an adaptive stress response. Conclusions While additional evidence is required to definitively establish an association between SE responsiveness and a specific physiological response, these results suggest that biotic defense activation may be antagonistic, likely related to the massive transcriptional and metabolic reprogramming that it elicits. A major issue for future work will be to determine how and if suppressing biotic defense activation could be used to promote a physiological state more conducive to SE induction. PMID:23937238

  14. Studies for Somatic Embryogenesis in Sweet Potato

    NASA Technical Reports Server (NTRS)

    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.

  15. Studies on Somatic Embryogenesis in Sweetpotato

    NASA Technical Reports Server (NTRS)

    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.

  16. Advances in Conifer Somatic Embryogenesis Since Year 2000.

    PubMed

    Klimaszewska, Krystyna; Hargreaves, Catherine; Lelu-Walter, Marie-Anne; Trontin, Jean-François

    2016-01-01

    This review compiles research results published over the last 14 years on conifer somatic embryogenesis (SE). Emphasis is placed on the newest findings that affect the response of seed embryos (typical explants) and shoot primordia (rare explants) to the induction of SE and long-term culture of early somatic embryos. Much research in recent years has focused on maturation of somatic embryos, with respect to both yield and quality, as an important stage for the production of a large number of vigorous somatic seedlings. Attempts to scale up somatic embryo production numbers and handling have resulted in a few bioreactor designs, the utility of which may prove beneficial for an industrial application. A few simplified cryopreservation methods for embryonal masses (EM) were developed as a means to ensure cost-efficient long-term storage of genotypes during clonal field testing. Finally, recent long-term studies on the growth of somatic trees in the field, including seed production yield and comparison of seed parameters produced by somatic versus seed-derived trees, are described. PMID:26619862

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

    PubMed

    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. PMID:26287694

  18. Spaceflight reduces somatic embryogenesis in orchardgrass (Poaceae)

    NASA Technical Reports Server (NTRS)

    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.

  19. Somatic Embryogenesis: Identified Factors that Lead to Embryogenic Repression. A Case of Species of the Same Genus

    PubMed Central

    Nic-Can, Geovanny I.; Galaz-Ávalos, Rosa M.; De-la-Peña, Clelia; Alcazar-Magaña, Armando; Wrobel, Kazimierz; Loyola-Vargas, Víctor M.

    2015-01-01

    Somatic embryogenesis is a powerful biotechnological tool for the mass production of economically important cultivars. Due to the cellular totipotency of plants, somatic cells under appropriate conditions are able to develop a complete functional embryo. During the induction of somatic embryogenesis, there are different factors involved in the success or failure of the somatic embryogenesis response. Among these factors, the origin of the explant, the culture medium and the in vitro environmental conditions have been the most studied. However, the secretion of molecules into the media has not been fully addressed. We found that the somatic embryogenesis of Coffea canephora, a highly direct embryogenic species, is disrupted by the metabolites secreted from C. arabica, a poorly direct embryogenic species. These metabolites also affect DNA methylation. Our results show that the abundance of two major phenolic compounds, caffeine and chlorogenic acid, are responsible for inhibiting somatic embryogenesis in C. canephora. PMID:26038822

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

    PubMed

    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. PMID:26619868

  1. Somatic Embryogenesis of Abies cephalonica Loud.

    PubMed

    Kraj?áková, Jana; Häggman, Hely

    2016-01-01

    Greek fir (Abies cephalonica Loudon) belongs to the Mediterranean fir species and is widely distributed in the mountains of Central and Southern Greece. Considering a climatic scenario, infestation by pathogens or insects and fire episodes, it has been proposed that Mediterranean firs could be in danger in some parts of their present range but, on the other hand, could also replace other species in more northern zones with temperate humid climates (e.g., silver fir, Abies alba Mill.). As fir species are generally highly productive and therefore important for commercial forestry, they have traditionally been involved in conventional tree improvement programs. A lot of effort has been put into the development of vegetative propagation methods for firs, in order to rapidly gain the benefits of traditional breeding to be utilized in reforestation. The present paper provides up to date information on protocols for somatic embryogenesis (i.e., the most promising in vitro method for vegetative propagation) of Greek fir. Moreover, the protocols for cryopreservation and long-term storage of embryogenic material are described as well. PMID:26619877

  2. Indirect somatic embryogenesis from petal explant of endangered wild population of Fritillaria imperialis.

    PubMed

    Mohammadi-Dehcheshmeh, Manijeh; Khalighi, Ahmad; Naderi, Roohangiz; Ebrahimie, Esmaeil; Sardari, Manoochehr

    2007-06-01

    Fritillaria imperialis is an endangered bulbous plant and therefore in vitro micropropagation of this plant will have a great importance for germplasm conservation and commercial production. Petal explants, for the first time, were cultured on media containing various concentrations of plant growth regulators. In addition, the effects of cold pretreatment and light on induction and regeneration of somatic embryogenesis trough callus were studied in detail. Cold pretreatment had inhibitory effects on somatic embryogenesis pathway. Among the different combinations of 6-Bnzylaminopurine (BAP), alpha-naphthaleneacetic acid (NAA) and indole-3-aceticacid (IAA) tested, B5 medium supplemented with 0.1 mg L(-1) BAP + 0.6 mg L(-1) NAA + 0.4 mg L(-1) IAA was the best treatment for bulblet production (6 bulblets per somatic embryogenesis callus). This research presents petal as a reliable material for micropropagation and germplasm conservation of Fritillaria imperialis. PMID:19086554

  3. Somatic embryogenesis and plant regeneration of cassava (Manihot esculenta Crantz) landraces from Cameroon.

    PubMed

    Mongomake, Kone; Doungous, Oumar; Khatabi, Behnam; Fondong, Vincent N

    2015-01-01

    A procedure to regenerate cassava (Manihot esculenta Crantz) cultivars from Cameroon via somatic embryogenesis (SE) was developed. Shoot apical meristems and immature leaf lobes were used as explants on Murashige and Skoog (MS) basal medium containing 33 or 50 µM of the auxins Picloram (Pic), 2,4-Dichlorophenoxyacetic acid (2,4-D), Dicamba (Dic), and ?-Naphthalene acetic acid. Cultivar performance was assessed using SE and number of somatic embryos produced. Overall, the frequency of primary somatic embryogenesis (PSE) and the mean number of somatic embryos produced varied considerably with genotype, type of auxin and concentration tested. For example, cultivar (cv.) Ngan Mbada showed the best performance on MS medium supplemented with 50 µM Pic with a SE frequency of 40 % and an average number of somatic embryos of 90. The second best performance was recorded in cv. Local Red on MS medium supplemented with 33 µM 2,4-D, where the SE frequency was 40 % and an average number of somatic embryos of 60.5. Cultivar Ekona Red recorded the best performance on medium supplemented with 50 µM Pic showing a SE frequency of 47 % and an average number of somatic embryos of 45. We further examined secondary and cyclic somatic embryogenesis (SSE, CSE) and both were also observed to vary with genotype, however, both exhibited significantly higher frequencies of SE compared with PSE. SE started to decline at the fourth cycle of embryogenesis. Examination of organogenesis showed that shoot bud induction from green cotyledons varied across cultivars and benzylaminopurine was shown to outperform Thidiazuron in the ability to induce organogenesis. Furthermore, the frequencies of bud induction were identical under light and dark conditions. Finally, regenerated plants grew easily in the greenhouse with 90-100 % survival rate and did not display detectable variation in morphology. PMID:26361578

  4. A temporary immersion system improves in vitro regeneration of peach palm through secondary somatic embryogenesis

    PubMed Central

    Steinmacher, D. A.; Guerra, M. P.; Saare-Surminski, K.; Lieberei, R.

    2011-01-01

    Background and Aims Secondary somatic embryogenesis has been postulated to occur during induction of peach palm somatic embryogenesis. In the present study this morphogenetic pathway is described and a protocol for the establishment of cycling cultures using a temporary immersion system (TIS) is presented. Methods Zygotic embryos were used as explants, and induction of somatic embryogenesis and plantlet growth were compared in TIS and solid culture medium. Light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to describe in vitro morphogenesis and accompany morpho-histological alterations during culture. Key Results The development of secondary somatic embryos occurs early during the induction of primary somatic embryos. Secondary somatic embryos were observed to develop continually in culture, resulting in non-synchronized development of these somatic embryos. Using these somatic embryos as explants allowed development of cycling cultures. Somatic embryos had high embryogenic potential (65·8 ± 3·0 to 86·2 ± 5·0 %) over the period tested. The use of a TIS greatly improved the number of somatic embryos obtained, as well as subsequent plantlet growth. Histological analyses showed that starch accumulation precedes the development of somatic embryos, and that these cells presented high nucleus/cytoplasm ratios and high mitotic indices, as evidenced by DAPI staining. Morphological and SEM observations revealed clusters of somatic embryos on one part of the explants, while other parts grew further, resulting in callus tissue. A multicellular origin of the secondary somatic embryos is hypothesized. Cells in the vicinity of callus accumulated large amounts of phenolic substances in their vacuoles. TEM revealed that these cells are metabolically very active, with the presence of numerous mitochondria and Golgi apparatuses. Light microscopy and TEM of the embryogenic sector revealed cells with numerous amyloplasts, large nuclei and nucleoli, and numerous plasmodesmata. Plantlets were obtained and after 3 months in culture their growth was significantly better in TIS than on solid culture medium. However, during acclimatization the survival rate of TIS-grown plantlets was lower. Conclusions The present study confirms the occurrence of secondary somatic embryos in peach palm and describes a feasible protocol for regeneration of peach palm in vitro. Further optimizations include the use of explants obtained from adult palms and improvement of somatic embryo conversion rates. PMID:21355009

  5. A microdroplet cell culture based high frequency somatic embryogenesis system for pigeonpea, Cajanus cajan (L.) Millsp.

    PubMed

    Kumar, Nagan Udhaya; Gnanaraj, Muniraj; Sindhujaa, Vajravel; Viji, Maluventhen; Manoharan, Kumariah

    2015-09-01

    A protocol for high frequency production of somatic embryos was worked out in pigeonpea, Cajanus cajan (L.) Millsp. The protocol involved sequential employment of embryogenic callus cultures, low density cell suspension cultures and a novel microdroplet cell culture system. The microdroplet cell cultures involved culture of a single cell in 10 ?I of Murashige and Skoog's medium supplemented with phytohormones, growth factors and phospholipid precursors. By employing the microdroplet cell cultures, single cells in isolation were grown into cell clones which developed somatic embryos. Further, 2,4-dichlorophenoxyacetic acid, kinetin, polyethylene glycol, putrescine, spermine, spermidine, choline chloride, ethanolamine and LiCl were supplemented to the low density cell suspension cultures and microdroplet cell cultures to screen for their cell division and somatic embryogenesis activity. Incubation of callus or the inoculum employed for low density cell suspension cultures and microdroplet cell cultures with polyethylene glycol was found critical for induction of somatic embryogenesis. Somatic embryogenesis at a frequency of 1.19, 3.16 and 6.51 per 10(6) cells was achieved in the callus, low density cell suspension cultures and microdroplet cell cultures, respectively. Advantages of employing microdroplet cell cultures for high frequency production of somatic embryos and its application in genetic transformation protocols are discussed. PMID:26548080

  6. Yield performance of cacao propagated by somatic embryogenesis and grafting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twelve cacao (Theobroma cacao) clones propagated by grafting and somatic embryogenesis and grown on an Ultisol soil were evaluated for five years under intensive management at Corozal, Puerto Rico. Preliminary data showed no significant differences between propagation methods for yield of dry beans ...

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

    PubMed

    Teixeira da Silva, Jaime A; 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'. PMID:26619873

  8. In vitro propagation of Lilium longiflorum var. ceb-dazzle through direct somatic embryogenesis.

    PubMed

    Khosravi, Solmaz; Azghandi, Ali Vatanpour; Mojtahedi, Narges; Haddad, Raheem

    2007-08-01

    Experiments were carried out to investigate the effects of various concentrations of Picloram (0, 1, 2, 3, 6 and 9 mg L(-1)), TDZ (0, 0.5, 1, 1.5 and 2 mg L(-1)), NAA (1.5 mg L(-1)) in combination with TDZ (0.08, 0.2 and 0.4 mg L(-1)), 2,4-D (2.5, 5 and 10 mg L(-1)) combined with BAP (0.25 mg L(-1)) and different types of explants (basal, central and distal part of the bulb scale) on direct somatic embryogenesis induction of Lilium longiflorum var. Ceb-Dazzle. The explants were surface sterilized and cultured on MS medium supplemented with 3% sucrose, 0.3% Phytagel and various concentrations of mentioned growth regulators. It was found that Picloram at a concentration of 2 mg L-' was the most effective treatment for induction of direct somatic embryogenesis and gave the highest number of embryos (18.6) on each explant. The explants from basal part of the bulb scale showed the best responses (19.9 embryos/explant). TDZ alone or combined with NAA in various concentrations was not able to induce somatic embryogenesis, but gave direct bulblet regeneration. Similar results were obtained for 2, 4-D and BAP combination treatments. Induced somatic embryos were transferred to MS medium without growth regulators for maturation and matured plantlets were successfully acclimatized and transferred to in vivo conditions. PMID:19070125

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

    PubMed Central

    Yang, Jingli; Wu, Songquan; Li, Chenghao

    2013-01-01

    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. PMID:23818829

  10. High efficiency secondary somatic embryogenesis in Hovenia dulcis Thunb. through solid and liquid cultures.

    PubMed

    Yang, Jingli; Wu, Songquan; Li, Chenghao

    2013-01-01

    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. PMID:23818829

  11. Somatic embryogenesis from leaf explants of Gladiolus anatolicus (Boiss.) Stapf.

    PubMed

    Emek, Yelda; Erdag, Bengi

    2007-04-15

    An in vitro micropropagation method by somatic embryogenesis was developed for Gladiolus anatolicus (Boiss.) Stapf using leaves of in vitro shoots obtained from lateral buds. Lateral buds removed from sterilized fresh corms were placed on Murashige and Skoog (MS) medium supplemented with various concentrations of N6-benzyladenine (BA) for shoot culture establishment. The highest number of shoot per lateral bud explant was on MS medium supplemented with 2 mg L(-1) BA (11.00 +/- 0.38). To induce somatic embryogenesis, leaves of in vitro shoots obtained from lateral buds were used as explant. Calli were obtained from middle and basal region of leaf explant cultured on MS basal medium supplemented with different concentrations of alpha-naphthaleneacetic acid: N6-benzyladenine (NAA:BA) ratio and without growth regulators. The highest rate of callus formation was obtained from basal part of leaves cultured on MS medium containing 5 mg L(-1) NAA in darkness (80 +/- 0.41%). Creamy-white and friable calli produced numerous somatic embryos on MS basal medium supplemented with 0.1 mg L(-1) BA within 4 weeks in light (On avarage 30 structures per callus). Well-developed somatic embryos were germinated on MS medium supplemented with 0.1 mg L(-1) BA and reduced sucrose concentration (20 g L(-1)). On this medium 40% of the somatic embryos developed into plantlets. Cormlet formation was observed on MS basal medium (30 g L(-1) sucrose) containing same concentration of BA. PMID:19069915

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  13. Somatic Embryogenesis in Peach-Palm (Bactris gasipaes) Using Different Explant Sources.

    PubMed

    Steinmacher, Douglas A; Heringer, Angelo Schuabb; Jiménez, Víctor M; Quoirin, Marguerite G G; Guerra, Miguel P

    2016-01-01

    Peach palm (Bactris gasipaes Kunth) is a member of the family Arecaceae and is a multipurpose but underutilized species. Nowadays, fruit production for subsistence and local markets, and heart-of-palm production for local, national, and international markets are the most important uses of this plant. Conventional breeding programs in peach palm are long-term efforts due to the prolonged generation time, large plant size, difficulties with controlled pollination and other factors. Although it is a caespitose palm, its propagation is currently based on seeds, as off-shoots are difficult to root. Hence, tissue culture techniques are considered to be the most likely strategy for efficient clonal plantlet regeneration of this species. Among various techniques, somatic embryogenesis offers the advantages of potential automated large-scale production and putative genetic stability of the regenerated plantlets. The induction of somatic embryogenesis in peach palm can be achieved by using different explant sources including zygotic embryos, immature inflorescences and thin cell layers from the young leaves and shoot meristems. The choice of a particular explant depends on whether clonal propagation is desired or not, as well as on the plant conditions and availability of explants. Protocols to induce and express somatic embryogenesis from different peach palm explants, up to acclimatization of plantlets, are described in this chapter. PMID:26619867

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

    PubMed Central

    De-la-Peña, Clelia; Nic-Can, Geovanny I.; Galaz-Ávalos, Rosa M.; Avilez-Montalvo, Randy; Loyola-Vargas, Víctor M.

    2015-01-01

    Somatic embryogenesis (SE) is a powerful tool for plant genetic improvement when used in combination with traditional agricultural techniques, and it is also an important technique 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 and 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 change in the genetic program of somatic cells, as well as moderating the transition between embryo developmental stages. In recent years, epigenetic mechanisms have emerged as critical factors during SE. Some early reports indicate that auxins and in vitro conditions 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 understanding of the role of epigenetic regulation of SE. In addition, we include a survey of different approaches to the study of SE, and new opportunities to focus SE studies. PMID:26347757

  15. Somatic Embryogenesis and Plant Regeneration of Brachiaria brizantha.

    PubMed

    Cabral, Glaucia B; Carneiro, Vera T C; Dusi, Diva M A; Martinelli, Adriana P

    2016-01-01

    The genus Brachiaria (Trin.) Griseb. belongs to the family Poaceae, order Poales, class Monocotyledonae. In Brachiaria brizantha (Hochst. ex A. Rich.) Stapf., embryogenic callus can be induced from seeds from apomictic plants, which results in high frequency somatic embryo development and plant regeneration. We report here a detailed protocol for callus induction from apomictic seed; followed by in vitro morphogenesis (somatic embryo and bud differentiation), plant regeneration, and acclimatization in the greenhouse. Important details regarding the positioning of seeds for callus induction and precautions to avoid endophytic contamination and the occurrence of albino plants are presented. PMID:26619875

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

    PubMed Central

    Heringer, Angelo Schuabb; Barroso, Tatiana; Macedo, Amanda Ferreira; Santa-Catarina, Claudete; Souza, Gustavo Henrique Martins Ferreira; Floh, Eny Iochevet Segal; de Souza-Filho, Gonçalo Apolinário; Silveira, Vanildo

    2015-01-01

    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. PMID:26035435

  17. Somatic Embryogenesis in Horse Chestnut (Aesculus hippocastanum L.).

    PubMed

    Capuana, Maurizio

    2016-01-01

    Embryogenic cultures of horse chestnut (Aesculus hippocastanum L.) can be obtained from different organs and tissues. We describe here the induction from stamen filaments and the procedures applied for the successive phases of somatic embryo development and maturation. Embryogenic tissues are obtained on Murashige and Skoog medium containing 9.0 ?M 2,4-dichlorophenoxyacetic acid. Somatic embryos develop after transfer to hormone-free medium enriched with glutamine. Maturation and germination of isolated embryos are achieved by transfer to medium containing polyethylene glycol 4000 and activated charcoal, successive desiccation treatment, and cold storage at 4 °C for 8 weeks. PMID:26619878

  18. High frequency regeneration via direct somatic embryogenesis and efficient Agrobacterium- mediated genetic transformation of tobacco

    PubMed Central

    Pathi, Krishna Mohan; Tula, Suresh; Tuteja, Narendra

    2013-01-01

    A direct somatic embryogenesis protocol was developed for four cultivars of Nicotiana species, by using leaf disc as an explant. Direct somatic embryogenesis of Nicotiana by using BAP and IAA has not been investigated so far. This method does not require formation of callus tissues which leads to somaclonal variations. The frequency of somatic embryogenesis was strongly influenced by the plant growth hormones. The somatic embryos developing directly from explant tissue were noticed after 6 d of culture. Somatic embryogenesis of a high frequency (87–96%) was observed in cultures of the all four genotypes (Nicotiana tabacum, N. benthamiyana, N. xanthi, N. t cv petihavana). The results showed that the best medium for direct somatic embryogenesis was MS supplemented with 2.5 mg/l, 0.2 mg/l IAA and 2% sucrose. Subculture of somatic embryos onto hormone free MS medium resulted in their conversion into plants for all genotypes. About 95% of the regenerated somatic embryos germinated into complete plantlets. The plants showed morphological and growth characteristics similar to those of seed-derived plants. Explants were transformed using Agrobacterium tumifacious LBA4404 plasmid pCAMBIA1301 harboring the GUS gene. The regenerated transgenic plants were confirmed by PCR analysis and histochemical GUS assay. The transformation efficiency obtained by using the Agrobacterium- mediated transformation was more than 95%. This method takes 6 wk to accomplish complete transgenic plants through direct somatic embryogenesis. The transgenic plantlets were acclimatized successfully with 98% survival in greenhouse and they showed normal morphological characteristics and were fertile. The regeneration and transformation method described herein is very simple, highly efficient and fast for the introduction of any foreign gene directly in tobacco through direct somatic embryogenesis. PMID:23518589

  19. High frequency regeneration via direct somatic embryogenesis and efficient Agrobacterium-mediated genetic transformation of tobacco.

    PubMed

    Pathi, Krishna Mohan; Tula, Suresh; Tuteja, Narendra

    2013-06-01

    A direct somatic embryogenesis protocol was developed for four cultivars of Nicotiana species, by using leaf disc as an explant. Direct somatic embryogenesis of Nicotiana by using BAP and IAA has not been investigated so far. This method does not require formation of callus tissues which leads to somaclonal variations. The frequency of somatic embryogenesis was strongly influenced by the plant growth hormones. The somatic embryos developing directly from explant tissue were noticed after 6 d of culture. Somatic embryogenesis of a high frequency (87-96%) was observed in cultures of the all four genotypes (Nicotiana tabacum, N. benthamiyana, N. xanthi, N. t cv petihavana). The results showed that the best medium for direct somatic embryogenesis was MS supplemented with 2.5 mg/l, 0.2 mg/l IAA and 2% sucrose. Subculture of somatic embryos onto hormone free MS medium resulted in their conversion into plants for all genotypes. About 95% of the regenerated somatic embryos germinated into complete plantlets. The plants showed morphological and growth characteristics similar to those of seed-derived plants. Explants were transformed using Agrobacterium tumifacious LBA4404 plasmid pCAMBIA1301 harboring the GUS gene. The regenerated transgenic plants were confirmed by PCR analysis and histochemical GUS assay. The transformation efficiency obtained by using the Agrobacterium- mediated transformation was more than 95%. This method takes 6 wk to accomplish complete transgenic plants through direct somatic embryogenesis. The transgenic plantlets were acclimatized successfully with 98% survival in greenhouse and they showed normal morphological characteristics and were fertile. The regeneration and transformation method described herein is very simple, highly efficient and fast for the introduction of any foreign gene directly in tobacco through direct somatic embryogenesis. PMID:23518589

  20. Proteomic Analysis of Immature Fraxinus mandshurica Cotyledon Tissues during Somatic Embryogenesis: Effects of Explant Browning on Somatic Embryogenesis

    PubMed Central

    Liu, Chun-Ping; Yang, Ling; Shen, Hai-Long

    2015-01-01

    Manchurian ash (Fraxinus mandshurica Rupr.) is a valuable hardwood species in Northeast China. In cultures of F. mandshurica, somatic embryos were produced mainly on browned explants. Therefore, we studied the mechanism of explant browning and its relationship with somatic embryogenesis (SE). We used explants derived from F. mandshurica immature zygotic embryo cotyledons as materials. Proteins were extracted from browned embryogenic explants, browned non-embryogenic explants, and non-brown explants, and then separated by 2-dimensional electrophoresis. Differentially and specifically expressed proteins were analyzed by mass spectrometry to identify proteins involved in the browning of explants and SE. Some stress response and defense proteins such as chitinases, peroxidases, aspartic proteinases, and an osmotin-like protein played important roles during SE of F. mandshurica. Our results indicated that explant browning might not be caused by the accumulation and oxidation of polyphenols only, but also by some stress-related processes, which were involved in programmed cell death (PCD), and then induced SE. PMID:26084048

  1. Influence of Abscisic Acid and Sucrose on Somatic Embryogenesis in Cactus Copiapoa tenuissima Ritt. forma mostruosa

    PubMed Central

    Lema-Rumi?ska, 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??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??M) and sucrose (1, 3, 5%). The results showed that a low concentration of ABA (0-1??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??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??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. PMID:23843737

  2. Calcium-mediated signaling during sandalwood somatic embryogenesis. Role for exogenous calcium as second messenger.

    PubMed

    Anil, V S; Rao, K S

    2000-08-01

    The possible involvement of Ca(2+)-mediated signaling in the induction/regulation of somatic embryogenesis from pro-embryogenic cells of sandalwood (Santalum album) has been investigated. (45)Ca(2+)-uptake studies and fura-2 fluorescence ratio photometry were used to measure changes in [Ca(2+)](cyt) of pro-embryogenic cells in response to culture conditions conducive for embryo development. Sandalwood pro-embryogenic cell masses (PEMs) are obtained in the callus proliferation medium that contains the auxin 2,4-dichlorophenoxyacetic acid. Subculture of PEMs into the embryo differentiation medium, which lacks 2,4-dichlorophenoxyacetic acid and has higher osmoticum, results in a 4-fold higher (45)Ca(2+) incorporation into the symplast. Fura-2 ratiometric analysis corroboratively shows a 10- to 16-fold increase in the [Ca(2+)](cyt) of PEMs, increasing from a resting concentration of 30 to 50 nM to 650 to 800 nM. Chelation of exogenous Ca(2+) with ethyleneglycol-bis(aminoethyl ether)-N,N'-tetraacetic acid arrests such an elevation in [Ca(2+)](cyt). Exogenous Ca(2+) when chelated or deprived also arrests embryo development and inhibits the accumulation of a sandalwood Ca(2+)-dependent protein kinase. However, such culture conditions do not cause cell death as the PEMs continue to proliferate to form larger cell clumps. Culture treatment with N-(6-aminohexyl)-5-chloro-1-naphthalene sulfonamide reduced embryogenic frequency by 85%, indicating that blockage of Ca(2+)-mediated signaling pathway(s) involving sandalwood Ca(2+)-dependent protein kinase and/or calmodulin causes the inhibition of embryogenesis. The observations presented are evidence to suggest a second messenger role for exogenous Ca(2+) during sandalwood somatic embryogenesis. PMID:10938349

  3. Somatic Embryogenesis in Olive (Olea europaea L. subsp. europaea var. sativa and var. sylvestris).

    PubMed

    Rugini, Eddo; Silvestri, Cristian

    2016-01-01

    Protocols for olive somatic embryogenesis from zygotic embryos and mature tissues have been described for both Olea europaea sub. europaea var. sativa and var. sylvestris. Immature zygotic embryos (no more than 75 days old), used after fruit collection or stored at 12-14 °C for 2-3 months, are the best responsive explants and very slightly genotype dependent, and one single protocol can be effective for a wide range of genotypes. On the contrary, protocols for mature zygotic embryos and for mature tissue of cultivars are often genotype specific, so that they may require many adjustments according to genotypes. The use of thidiazuron and cefotaxime seems to be an important trigger for induction phase particularly for tissues derived from cultivars. Up to now, however, the application of this technique for large-scale propagation is hampered also by the low rate of embryo germination; it proves nonetheless very useful for genetic improvement. PMID:26619870

  4. Somatic Embryogenesis in Broad-Leaf Woody Plants: What We Can Learn from Proteomics.

    PubMed

    Correia, Sandra I; Alves, Ana C; Veríssimo, Paula; Canhoto, Jorge M

    2016-01-01

    Proteomic approaches have been used to understand several regulatory aspects of plant development. Somatic embryogenesis is one of those developmental pathways that have beneficiated from the integration of proteomics data to the understanding of the molecular mechanisms that control embryogenic competence acquisition, somatic embryo development and conversion into viable plants. Nevertheless, most of the results obtained are based on the traditional model systems, very often not easily compared with the somatic embryogenesis systems of economical relevant woody species. The aim of this work is to summarize some of the applications of proteomics in the understanding of particular aspects of the somatic embryogenesis process in broad-leaf woody plants (model and non-model systems). PMID:26619861

  5. From Stress to Embryos: Some of the Problems for Induction and Maturation of Somatic Embryos.

    PubMed

    Ochatt, Sergio J; Revilla, Maria Angeles

    2016-01-01

    Although somatic embryogenesis has been successfully achieved in numerous plant species, little is known about the mechanism(s) underlying this process. Changes in the balance of growth regulators of the culture medium, osmolarity, or amino acids as well as the genotype and developmental stage of the tissue used as initial explant may have a pivotal influence on the induction of somatic embryogenic cultures. Moreover, different stress agents (ethylene, activated charcoal, cold or heat or electrical shocks), as well as abscisic acid, can also foster the induction or further development of somatic embryos. In the process, cells first return to a stem cell-like status and then either enter their new program or dye when the stress level exceeds cell tolerance. Recalcitrance to differentiation of somatic cells into embryos is frequently observed, and problems such as secondary or recurrent embryogenesis, embryo growth arrest (at the globular stage or during the transition from torpedo to cotyledonary stage), and development of only the aerial part of somatic embryos can appear, interfering with normal germination and conversion of embryos to plants. Some solutions to solve these problems associated to embryogenesis are proposed and two very efficient somatic embryogenesis protocols for two model plant species are detailed. PMID:26619886

  6. Somatic embryogenesis, maturation and DNA transfer in Pinus 

    E-print Network

    Marek, Kimberly Ann

    1994-01-01

    rapidly and maintained its embryogenic potential, was used for somatic embryo maturation. There was a high turnover of Stage 3 (crown and elongated) somatic embryos from embryogenic tissue with 65 plantlets recovered. Genotype, culture medium...

  7. Microarray Analysis of Siberian Ginseng Cyclic Somatic Embryogenesis Culture Systems Provides Insight into Molecular Mechanisms of Embryogenic Cell Cluster Generation

    PubMed Central

    Zhou, Chenguang; Liu, Likun; Li, Chenghao

    2014-01-01

    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. PMID:24743225

  8. Somatic embryogenesis, scanning electron microscopy, histology and biochemical analysis at different developing stages of embryogenesis in six date palm (Phoenix dactylifera L.) cultivars.

    PubMed

    Aslam, Junaid; Khan, Saeed Ahmad; Cheruth, Abdul Jaleel; Mujib, Abdul; Sharma, Maheshwar Pershad; Srivastava, Prem Shanker

    2011-10-01

    An efficient somatic embryogenesis system has been established in six date palm (Phoenix dactylifera L.) cultivars (Barhee, Zardai, Khalasah, Muzati, Shishi and Zart). Somatic embryogenesis (SE) was growth regulators and cultivars dependent. Friable embryogenic callus was induced from excised shoot tips on MS medium supplemented with various auxins particularly 2,4-dichlorophenoxyacetic acid (2,4-D, 1.5 mg 1(-l)). Suspension culture increased embryogenesis potentiality. Only a-naphthaleneacetic acid (NAA, 0.5 mg 1(-1)) produced somatic embryos in culture. Somatic embryos germinated and converted into plantlets in N(6)-benzyladenine (BAP, 0.75 mg 1(-l)) added medium following a treatment with thidiazuron (TDZ, 1.0 mg 1(-l)) for maturation. Scanning electron microscopy showed early stages of somatic embryo particularly, globular types, and was in masses. Different developing stages of embryogenesis (heart, torpedo and cotyledonary) were observed under histological preparation of embryogenic callus. Biochemical screening at various stages of somatic embryogenesis (embryogenic callus, somatic embryos, matured, germinated embryos and converted plantlets) of date palm cultivars has been conducted and discussed in detail. The result discussed in this paper indicates that somatic embryos were produced in numbers and converted plantlets can be used as a good source of alternative propagation. Genetic modification to the embryo precursor cell may improve the fruit quality and yield further. PMID:23961149

  9. Somatic embryogenesis, scanning electron microscopy, histology and biochemical analysis at different developing stages of embryogenesis in six date palm (Phoenix dactylifera L.) cultivars

    PubMed Central

    Aslam, Junaid; Khan, Saeed Ahmad; Cheruth, Abdul Jaleel; Mujib, Abdul; Sharma, Maheshwar Pershad; Srivastava, Prem Shanker

    2011-01-01

    An efficient somatic embryogenesis system has been established in six date palm (Phoenix dactylifera L.) cultivars (Barhee, Zardai, Khalasah, Muzati, Shishi and Zart). Somatic embryogenesis (SE) was growth regulators and cultivars dependent. Friable embryogenic callus was induced from excised shoot tips on MS medium supplemented with various auxins particularly 2,4-dichlorophenoxyacetic acid (2,4-D, 1.5 mg 1?l). Suspension culture increased embryogenesis potentiality. Only a-naphthaleneacetic acid (NAA, 0.5 mg 1?1) produced somatic embryos in culture. Somatic embryos germinated and converted into plantlets in N6-benzyladenine (BAP, 0.75 mg 1?l) added medium following a treatment with thidiazuron (TDZ, 1.0 mg 1?l) for maturation. Scanning electron microscopy showed early stages of somatic embryo particularly, globular types, and was in masses. Different developing stages of embryogenesis (heart, torpedo and cotyledonary) were observed under histological preparation of embryogenic callus. Biochemical screening at various stages of somatic embryogenesis (embryogenic callus, somatic embryos, matured, germinated embryos and converted plantlets) of date palm cultivars has been conducted and discussed in detail. The result discussed in this paper indicates that somatic embryos were produced in numbers and converted plantlets can be used as a good source of alternative propagation. Genetic modification to the embryo precursor cell may improve the fruit quality and yield further. PMID:23961149

  10. Regeneration of Solanum nigrum by Somatic Embryogenesis, Involving Frog Egg-Like Body, a Novel Structure

    PubMed Central

    Xu, Kedong; Chang, Yunxia; Liu, Kun; Wang, Feige; Liu, Zhongyuan; Zhang, Ting; Li, Tong; Zhang, Yi; Zhang, Fuli; Zhang, Ju; Wang, Yan; Niu, Wei; Jia, Shuzhao; Xie, Hengchang; Tan, Guangxuan; Li, Chengwei

    2014-01-01

    A new protocol was established for the regeneration of Solanum nigrum by frog egg-like bodies (FELBs), which are novel somatic embryogenesis (SE) structures induced from the root, stem, and leaf explants. The root, stem, and leaf explants (93.33%, 85.10%, and 100.00%, respectively) were induced to form special embryonic calli on Murashige and Skoog (MS) medium containing 1.0 mg/L 2,4-dichlorophenoxyacetic acid, under dark condition. Further, special embryonic calli from the root, stem, and leaf explants (86.97%, 83.30%, and 99.47%, respectively) were developed into FELBs. Plantlets of FELBs from the three explants were induced in vitro on MS medium supplemented with 5.0 mg/L 6-benzylaminopurine and 0.1 mg/L gibberellic acid, and 100.00% plantlet induction rates were noted. However, plantlet induction in vivo on MS medium supplemented with 20 mg/L thidiazuron showed rates of 38.63%, 15.63%, and 61.30% for the root, stem, and leaf explants, respectively, which were lower than those of the in vitro culture. Morphological and histological analyses of FELBs at different development stages revealed that they are a novel type of SE structure that developed from the mesophyll (leaf) or cortex (stem and root) cells of S. nigrum. PMID:24896090

  11. The effectiveness of somatic embryogenesis in eliminating the cocoa swollen shoot virus from infected cocoa trees.

    PubMed

    Quainoo, A K; Wetten, A C; Allainguillaume, J

    2008-04-01

    Investigations were undertaken on the use of somatic embryogenesis to generate cocoa swollen shoot virus (CSSV) disease free clonal propagules from infected trees. Polymerase chain reaction (PCR) capillary electrophoresis revealed the presence of CSSV in all the callus tissues induced from the CSSV-infected Amelonado cocoa trees (T1, T2 and T4). The virus was transmitted to primary somatic embryos induced from the infected callus tissues at the rate of 10 (19%), 18 (14%) and 16 (15%) for T1, T2 and T4, respectively. Virus free primary somatic embryos from the infected callus tissues converted into plantlets tested CSSV negative by PCR/capillary electrophoresis 2 years after weaning. Secondary somatic embryos induced from the CSSV-infected primary somatic embryos revealed the presence of viral fragments at the rate of 4 (4%) and 9 (9%) for T2 and T4, respectively. Real-time PCR revealed 23 of the 24 secondary somatic embryos contained no detectable virus. Based on these findings, it is proposed that progressive elimination of the CSSV in infected cocoa trees occurred from primary embryogenesis to secondary embryogenesis. PMID:18294704

  12. Somatic embryogenesis and organogenesis from cryopreserved shoot tips of Lilium Oriental hybrid ‘Siberia’

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Somatic embryogenesis and organogenesis were achieved from cryopreserved shoot tips of Lilium Oriental hybrid ‘Siberia’. Shoot tips (1.5-2 mm) were excised from adventitious shoots that were regenerated from basal leaf segments. Precultured shoot tips were then treated with MS containing 0.4 M sucro...

  13. Research note Putrescine enhances somatic embryogenesis and plant regeneration in upland

    E-print Network

    Chee, Peng W.

    production on the EMMS2-0.5 Putrescine treatment as compared to EMMS2 alone for cotton lines PD 97019 and GA ­ indole-3-acetic acid; BA ­ benzyladenine; 2,4-DD ­ 2,4-dichlorophenoxyacetic acid; MS ­ Murashige that are capable of inducing somatic embryogenesis (Mishra et al., 2003) and the efficiency of SE production were

  14. Control of somatic embryogenesis and embryo development by AP2 transcription factors.

    PubMed

    El Ouakfaoui, Souad; Schnell, Jaimie; Abdeen, Ashraf; Colville, Adam; Labbé, Hélène; Han, Shuyou; Baum, Bernard; Laberge, Serge; Miki, Brian

    2010-11-01

    Members of the AP2 family of transcription factors, such as BABY BOOM (BBM), play important roles in cell proliferation and embryogenesis in Arabidopsis thaliana (AtBBM) and Brassica napus (BnBBM) but how this occurs is not understood. We have isolated three AP2 genes (GmBBM1, GmAIL5, GmPLT2) from somatic embryo cultures of soybean, Glycine max (L.) Merr, and discovered GmBBM1 to be homologous to AtBBM and BnBBM. GmAIL5 and GmPLT2 were homologous to Arabidopsis AINTEGUMENTA-like5 (AIL5) and PLETHORA2 (PLT2), respectively. Constitutive expression of GmBBM1 in Arabidopsis induced somatic embryos on vegetative organs and other pleiotropic effects on post-germinative vegetative organ development. Sequence comparisons of BBM orthologues revealed the presence of ten sequence motifs outside of the AP2 DNA-binding domains. One of the motifs, bbm-1, was specific to the BBM-like genes. Deletion and domain swap analyses revealed that bbm-1 was important for somatic embryogenesis and acted cooperatively with at least one other motif, euANT2, in the regulation of somatic embryogenesis and embryo development in transgenic Arabidopsis. The results provide new insights into the mechanisms by which BBM governs embryogenesis. PMID:20798978

  15. Plant CellReports (1992)11:122-125 Repetitive somatic embryogenesis from peanut cultures in liquid medium

    E-print Network

    Parrott, Wayne

    1992-01-01

    Plant CellReports (1992)11:122-125 Repetitive somatic embryogenesis from peanut cultures in liquid. A regenerationsystembasedon repetitive somaticembryogenesiswasdevelopedfor peanut(Arachis hypogaeaL.). Embryogenic Plantregenerationfromculturedtissuesof peanut hasbeenreportedsporadicallyfor nearly 15years. Most of the earlier reports described

  16. Somatic embryogenesis in Arabidopsis thaliana is facilitated by mutations in genes repressing meristematic cell divisions.

    PubMed Central

    Mordhorst, A P; Voerman, K J; Hartog, M V; Meijer, E A; van Went, J; Koornneef, M; de Vries, S C

    1998-01-01

    Embryogenesis in plants can commence from cells other than the fertilized egg cell. Embryogenesis initiated from somatic cells in vitro is an attractive system for studying early embryonic stages when they are accessible to experimental manipulation. Somatic embryogenesis in Arabidopsis offers the additional advantage that many zygotic embryo mutants can be studied under in vitro conditions. Two systems are available. The first employs immature zygotic embryos as starting material, yielding continuously growing embryogenic cultures in liquid medium. This is possible in at least 11 ecotypes. A second, more efficient and reproducible system, employing the primordia timing mutant (pt allelic to hpt, cop2, and amp1), was established. A significant advantage of the pt mutant is that intact seeds, germinated in 2,4-dichlorophenoxyacetic acid (2, 4-D) containing liquid medium, give rise to stable embryonic cell cultures, circumventing tedious hand dissection of immature zygotic embryos. pt zygotic embryos are first distinguishable from wild type at early heart stage by a broader embryonic shoot apical meristem (SAM). In culture, embryogenic clusters originate from the enlarged SAMs. pt somatic embryos had all characteristic embryo pattern elements seen in zygotic embryos, but with higher and more variable numbers of cells. Embryogenic cell cultures were also established from seedling, of other mutants with enlarged SAMs, such as clavata (clv). pt clv double mutants showed additive effects on SAM size and an even higher frequency of seedlings producing embryogenic cell lines. pt clv double mutant plants had very short fasciated inflorescence stems and additive effects on the number of rosette leaves. This suggests that the PT and CLV genes act in independent pathways that control SAM size. An increased population of noncommitted SAM cells may be responsible for facilitated establishment of somatic embryogenesis in Arabidopsis. PMID:9611173

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

    PubMed

    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. PMID:25716878

  18. Identification of a transitional cell state in the developmental pathway to carrot somatic embryogenesis

    PubMed Central

    1992-01-01

    We have located a novel carbohydrate epitope in the cell walls of certain single cells in embryogenic, but not in non-embryogenic, suspension cultures of carrot. Expression of this epitope, recognized by the mAb JIM8, is regulated during initiation, proliferation, and prolonged growth of suspension cultures such that changes in the abundance of JIM8-reactive cells always precede equivalent changes in embryogenic potential. Therefore, a direct correlation exists between the presence of the JIM8-reactive cell wall epitope and somatic embryo formation. The JIM8-reactive cell wall epitope is expressed in the cell walls of three types of single cells and one type of cell cluster. One of the single cell types seems able to follow one of two phytohormone- controlled developmental pathways, either a cell elongation pathway that eventually leads to cell death, or a cell division pathway that gives rise to proembryogenic masses. We demonstrate that all JIM8- reactive cell types in embryogenic carrot suspension cultures are developmentally related, and that the switch by one of them to somatic embryogenesis is accompanied by the immediate dissipation of the JIM8- reactive cell wall epitope. The cell wall carbohydrate epitope recognized by JIM8 therefore represents a cell wall marker for a very early transitional cell state in the developmental pathway to carrot somatic embryogenesis. PMID:1280275

  19. Do Mitochondria Play a Central Role in Stress-Induced Somatic Embryogenesis?

    PubMed

    Arnholdt-Schmitt, Birgit; Ragonezi, Carla; Cardoso, Hélia

    2016-01-01

    This review highlights a four-step rational for the hypothesis that mitochondria play an upstream central role for stress-induced somatic embryogenesis (SE): (1) Initiation of SE is linked to programmed cell death (PCD) (2) Mitochondria are crucially connected to cell death (3) SE is challenged by stress per se (4) Mitochondria are centrally linked to plant stress response and its management. Additionally the review provides a rough perspective for the use of mitochondrial-derived functional marker (FM) candidates to improve SE efficiency. It is proposed to apply SE systems as phenotyping tool for identifying superior genotypes with high general plasticity under severe plant stress conditions. PMID:26619859

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

    PubMed Central

    Azad, Md. Abul Kalam; Rabbani, Md. Golam; Amin, Latifah

    2012-01-01

    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. PMID:23235330

  1. A mathematical model for the coreceptors SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE1 and SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE3 in BRASSINOSTEROID INSENSITIVE1-mediated signaling.

    PubMed

    van Esse, Wilma; van Mourik, Simon; Albrecht, Catherine; van Leeuwen, Jelle; de Vries, Sacco

    2013-11-01

    Brassinosteroids (BRs) are key regulators in plant growth and development. The main BR-perceiving receptor in Arabidopsis (Arabidopsis thaliana) is BRASSINOSTEROID INSENSITIVE1 (BRI1). Seedling root growth and hypocotyl elongation can be accurately predicted using a model for BRI1 receptor activity. Genetic evidence shows that non-ligand-binding coreceptors of the SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) family are essential for BRI1 signal transduction. A relatively simple biochemical model based on the properties of SERK loss-of-function alleles explains complex physiological responses of the BRI1-mediated BR pathway. The model uses BRI1-BR occupancy as the central estimated parameter and includes BRI1-SERK interaction based on mass action kinetics and accurately describes wild-type root growth and hypocotyl elongation. Simulation studies suggest that the SERK coreceptors primarily act to increase the magnitude of the BRI1 signal. The model predicts that only a small number of active BRI1-SERK complexes are required to carry out BR signaling at physiological ligand concentration. Finally, when calibrated with single mutants, the model predicts that roots of the serk1serk3 double mutant are almost completely brassinolide (BL) insensitive, while the double mutant hypocotyls remain sensitive. This points to residual BRI1 signaling or to a different coreceptor requirement in shoots. PMID:24072582

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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. ...

  3. Induction of somatic embryos in Arabidopsis requires local YUCCA expression mediated by the down-regulation of ethylene biosynthesis.

    PubMed

    Bai, Bo; Su, Ying Hua; Yuan, Jia; Zhang, Xian Sheng

    2013-07-01

    Somatic embryogenesis is an important experimental model for studying cellular and molecular mechanisms of early embryo development. Although it has long been known that removal of exogenous auxin from medium results in somatic embryogenesis, the mechanisms underlying the initiation of somatic embryos (SEs) are poorly understood. In this study, we showed that YUCCAs (YUCs) encoding key enzymes in auxin biosynthesis are required for SE induction in Arabidopsis. To identify other factors mediating SE initiation, we performed transcriptional profiling and gene expression analysis. The results showed that genes involved in ethylene biosynthesis and its responses were down-regulated during SE initiation. Ethylene level decreased progressively during SE initiation, whereas treatment with the metabolic precursor of ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), or mutation of ETHYLENE-OVERPRODUCTION1 (ETO1) disrupted SE induction, suggesting that ethylene plays a role in this process. Suppression of SE induction was also observed in the constitutive triple response 1 (ctr1) mutant, in which ethylene signaling was enhanced. These results indicate that down-regulation of not only ethylene biosynthesis, but also ethylene response is critical for SE induction. We further showed that ethylene disturbed SE initiation through inhibiting YUC expression that might be involved in local auxin biosynthesis and subsequent auxin distribution. Our results provide new information on the mechanisms of hormone-regulated SE initiation. PMID:23271028

  4. Doubled haploid production from Spanish onion (Allium cepa L.) germplasm: embryogenesis induction, plant regeneration and chromosome doubling

    PubMed Central

    Fayos, Oreto; Vallés, María P.; Garcés-Claver, Ana; Mallor, Cristina; Castillo, Ana M.

    2015-01-01

    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 2–3 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 ?M APM in liquid medium. However, the application of 25 ?M 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 four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis efficiency. PMID:26074944

  5. Doubled haploid production from Spanish onion (Allium cepa L.) germplasm: embryogenesis induction, plant regeneration and chromosome doubling.

    PubMed

    Fayos, Oreto; Vallés, María P; Garcés-Claver, Ana; Mallor, Cristina; Castillo, Ana M

    2015-01-01

    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 2-3 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 ?M APM in liquid medium. However, the application of 25 ?M 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 four regenerated lines. In this study, doubled haploid plants were produced from the four Spanish cultivars, however further improvements are needed to increase their gynogenesis efficiency. PMID:26074944

  6. Genome-wide identification, classification and analysis of HD-ZIP gene family in citrus, and its potential roles in somatic embryogenesis regulation.

    PubMed

    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. PMID:26232336

  7. Timing of bud set in Picea abies is regulated by a memory of temperature during zygotic and somatic embryogenesis.

    PubMed

    Kvaalen, Harald; Johnsen, Oystein

    2008-01-01

    It has been shown previously that height growth and bud phenology are influenced by the temperature during zygotic embryogenesis in Picea abies. To test whether this phenomenon operates within individual plants, clones produced through somatic embryogenesis were used. Seeds were from a full-sib family produced in both a cold (outdoor) and a warm (inside a glasshouse) environment. Embryogenic clones derived from mature zygotic embryos from both crossing environments were cultured at 18, 23 and 28 degrees C during the proliferation and embryo maturation steps. After the second growing season in a glasshouse, plants from the warm seed production environment were taller and had significantly later bud set. For the first time, it is also shown that plants are influenced by the in vitro temperature during somatic embryo development. The warmer the temperature, the later the plants formed terminal buds. The differences were similar to those produced by a provenance separation of 4-6 degrees of latitude. The results indicate that there exists a mechanism in P. abies that operates during embryo development and adjusts the timing of bud set in accordance with the temperature conditions in which the mother tree lives. This in turn counteracts negative effects of gene flow among populations located along altitudinal and latitudinal gradients. PMID:17924949

  8. Maize miRNA and target regulation in response to hormone depletion and light exposure during somatic embryogenesis

    PubMed Central

    Chávez-Hernández, Elva C.; Alejandri-Ramírez, Naholi D.; Juárez-González, Vasti T.; Dinkova, Tzvetanka D.

    2015-01-01

    Maize somatic embryogenesis (SE) is induced from the immature zygotic embryo in darkness and under the appropriate hormones' levels. Small RNA expression is reprogrammed and certain miRNAs become particularly enriched during induction while others, characteristic to the zygotic embryo, decrease. To explore the impact of different environmental cues on miRNA regulation in maize SE, we tested specific miRNA abundance and their target gene expression in response to photoperiod and hormone depletion for two different maize cultivars (VS-535 and H-565). The expression levels of miR156, miR159, miR164, miR168, miR397, miR398, miR408, miR528, and some predicted targets (SBP23, GA-MYB, CUC2, AGO1c, LAC2, SOD9, GR1, SOD1A, PLC) were examined upon staged hormone depletion in the presence of light photoperiod or darkness. Almost all examined miRNA, except miR159, increased upon hormone depletion, regardless photoperiod absence/presence. miR528, miR408, and miR398 changed the most. On the other hand, expression of miRNA target genes was strongly regulated by the photoperiod exposure. Stress-related miRNA targets showed greater differences between cultivars than development-related targets. miRNA/target inverse relationship was more frequently observed in darkness than light. Interestingly, miR528, but not miR159, miR168 or miR398, was located on polyribosome fractions suggesting a role for this miRNA at the level of translation. Overall our results demonstrate that hormone depletion exerts a great influence on specific miRNA expression during plant regeneration independently of light. However, their targets are additionally influenced by the presence of photoperiod. The reproducibility or differences observed for particular miRNA-target regulation between two different highly embryogenic genotypes provide clues for conserved miRNA roles within the SE process. PMID:26257760

  9. A Lower pH Value Benefits Regeneration of Trichosanthes kirilowii by Somatic Embryogenesis, Involving Rhizoid Tubers (RTBs), a Novel Structure

    PubMed Central

    Xu, Ke-dong; Chang, Yun-xia; Zhang, Ju; Wang, Pei-long; Wu, Jian-xin; Li, Yan-yan; Wang, Xiao-wen; Wang, Wei; Liu, Kun; Zhang, Yi; Yu, De-shui; Liao, Li-bing; Li, Yi; Ma, Shu-ya; Tan, Guang-xuan; Li, Cheng-wei

    2015-01-01

    A new approach was established for the regeneration of Trichosanthes kirilowii from root, stem, and leaf explants by somatic embryogenesis (SE), involving a previously unreported SE structure, rhizoid tubers (RTBs). During SE, special rhizoids were first induced from root, stem, and leaf explants with average rhizoid numbers of 62.33, 40.17, and 11.53 per explant, respectively, on Murashige and Skoog (MS) medium (pH 4.0) supplemented with 1.0?mg/L 1-naphthaleneacetic acid (NAA) under dark conditions. Further, one RTB was formed from each of the rhizoids on MS medium (pH 4.0) supplemented with 20?mg/L thidiazuron (TDZ) under light conditions. In the suitable range (pH 4.0–9.0), a lower pH value increased the induction of rhizoids and RTBs. Approximately 37.77, 33.47, and 31.07% of in vivo RTBs from root, stem, and leaf explants, respectively, spontaneously developed into multiple plantlets on the same MS medium (supplemented with 20?mg/L TDZ) for induction of RTBs, whereas >95.00% of in vitro RTBs from each kind of explant developed into multiple plantlets on MS medium supplemented with 5.0?mg/L 6-benzylaminopurine (BAP). Morphological and histological analyses revealed that RTB is a novel type of SE structure that develops from the cortex cells of rhizoids. PMID:25744384

  10. Characterization and expression analysis of SOMATIC EMBRYOGENESIS RECEPTOR KINASE (SERK) genes in sexual and apomictic Paspalum notatum.

    PubMed

    Podio, Maricel; Felitti, Silvina Andrea; Siena, Lorena Adelina; Delgado, Luciana; Mancini, Micaela; Seijo, José Guillermo; González, Ana María; Pessino, Silvina Claudia; Ortiz, Juan Pablo A

    2014-03-01

    The SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE (SERK) gene plays a fundamental role in somatic embryogenesis of angiosperms, and is associated with apomixis in Poa pratensis. The objective of this work was to isolate, characterize and analyze the expression patterns of SERK genes in apomictic and sexual genotypes of Paspalum notatum. A conserved 200-bp gene fragment was amplified from genomic DNA with heterologous primers, and used to initiate a chromosomal walking strategy for cloning the complete sequence. This procedure allowed the isolation of two members of the P. notatum SERK family; PnSERK1, which is similar to PpSERK1, and PnSERK2, which is similar to ZmSERK2 and AtSERK1. Phylogenetic analyses indicated that PnSERK1 and PnSERK2 represent paralogous sequences. Southern-blot hybridization indicated the presence of at least three copies of SERK genes in the species. qRT-PCR analyses revealed that PnSERK2 was expressed at significantly higher levels than PnSERK1 in roots, leaves, reproductive tissues and embryogenic calli. Moreover, in situ hybridization experiments revealed that PnSERK2 displayed a spatially and chronologically altered expression pattern in reproductive organs of the apomictic genotype with respect to the sexual one. PnSERK2 is expressed in nucellar cells of the apomictic genotype at meiosis, but only in the megaspore mother cell in the sexual genotype. Therefore, apomixis onset in P. notatum seems to be correlated with the expression of PnSERK2 in nucellar tissue. PMID:24146222

  11. Yield performance and bean quality traits of cacao propagated by somatic embryogenesis and grafting

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twelve cacao (Theobroma cacao) clones propagated by grafting and rooted cuttings of somatic embryo-derived plants were grown on an Ultisol soil at Corozal, Puerto Rico and evaluated for six years under intensive management. Year, variety, the year x variety and propagation treatment x variety intera...

  12. Transcript profiling reveals complex auxin signalling pathway and transcription regulation involved in dedifferentiation and redifferentiation during somatic embryogenesis in cotton

    PubMed Central

    2012-01-01

    Background Somatic embryogenesis (SE), by which somatic cells of higher plants can dedifferentiate and reorganize into new plants, is a notable illustration of cell totipotency. However, the precise molecular mechanisms regulating SE remain unclear. To characterize the molecular events of this unique process, transcriptome analysis, in combination with biochemical and histological approaches, were conducted in cotton, a typical plant species in SE. Genome-wide profiling of gene expression allowed the identification of novel molecular markers characteristic of this developmental process. Results RNA-Seq was used to identify 5,076 differentially expressed genes during cotton SE. Expression profile and functional assignments of these genes indicated significant transcriptional complexity during this process, associated with morphological, histological changes and endogenous indole-3-acetic acid (IAA) alteration. Bioinformatics analysis showed that the genes were enriched for basic processes such as metabolic pathways and biosynthesis of secondary metabolites. Unigenes were abundant for the functions of protein binding and hydrolase activity. Transcription factor–encoding genes were found to be differentially regulated during SE. The complex pathways of auxin abundance, transport and response with differentially regulated genes revealed that the auxin-related transcripts belonged to IAA biosynthesis, indole-3-butyric acid (IBA) metabolism, IAA conjugate metabolism, auxin transport, auxin-responsive protein/indoleacetic acid-induced protein (Aux/IAA), auxin response factor (ARF), small auxin-up RNA (SAUR), Aux/IAA degradation, and other auxin-related proteins, which allow an intricate system of auxin utilization to achieve multiple purposes in SE. Quantitative real-time PCR (qRT-PCR) was performed on selected genes with different expression patterns and functional assignments were made to demonstrate the utility of RNA-Seq for gene expression profiles during cotton SE. Conclusion We report here the first comprehensive analysis of transcriptome dynamics that may serve as a gene expression profile blueprint in cotton SE. Our main goal was to adapt the RNA-Seq technology to this notable development process and to analyse the gene expression profile. Complex auxin signalling pathway and transcription regulation were highlighted. Together with biochemical and histological approaches, this study provides comprehensive gene expression data sets for cotton SE that serve as an important platform resource for further functional studies in plant embryogenesis. PMID:22817809

  13. LEAFY COTYLEDON2 (LEC2) promotes embryogenic induction in somatic tissues of Arabidopsis, via YUCCA-mediated auxin biosynthesis.

    PubMed

    Wójcikowska, Barbara; Jaskó?a, Karolina; G?siorek, Przemys?aw; Meus, Magdalena; Nowak, Katarzyna; Gaj, Ma?gorzata D

    2013-09-01

    The LEAFY COTYLEDON2 (LEC2) transcription factor with a plant-specific B3 domain plays a central role in zygotic and somatic embryogenesis (SE). LEC2 overexpression induced in planta leads to spontaneous somatic embryo formation, but impairs the embryogenic response of explants cultured in vitro under auxin treatment. The auxin-related functions of LEC2 appear during SE induction, and the aim of the present study was to gain further insights into this phenomenon. To this end, the effect of LEC2 overexpression on the morphogenic responses of Arabidopsis explants cultured in vitro under different auxin treatments was evaluated. The expression profiles of the auxin biosynthesis genes were analysed in embryogenic cultures with respect to LEC2 activity. The results showed that LEC2 overexpression severely modifies the requirement of cultured explants for an exogenous auxin concentration at a level that is effective in SE induction and suggested an increase in the auxin content in 35S::LEC2-GR transgenic explants. The assumption of an LEC2 promoted increase in endogenous auxin in cultured explants was further supported by the expression profiling of the genes involved in auxin biosynthesis. The analysis indicated that YUCCAs and TAA1, working in the IPA-YUC auxin biosynthesis pathway, are associated with SE induction, and that the expression of three YUCCA genes (YUC1, YUC4 and YUC10) is associated with LEC2 activity. The results also suggest that the IAOx-mediated auxin biosynthesis pathway involving ATR1/MYB34 and CYP79B2 does not seem to be involved in SE induction. We conclude that de novo auxin production via the tryptophan-dependent IPA-YUC auxin biosynthesis pathway is implicated in SE induction, and that LEC2 plays a key role in this mechanism. PMID:23722561

  14. Somatic embryogenesis, tetraploidy, and variant leaf morphology in transgenic diploid strawberry (Fragaria vesca subspecies vesca ‘Hawaii 4’)

    PubMed Central

    2014-01-01

    Background The diploid (2n = 2x = 14) strawberry model plant Fragaria vesca ssp. vesca ‘Hawaii 4’ was employed for functional analysis of expressed DNA sequences initially identified as being unique to Fragaria and of unknown or poorly understood function. ‘Hawaii 4’ is prominent in strawberry research due to its ease of Agrobacterium-mediated transformation and regenerability, and its status as the source of the first complete strawberry genomic sequence. Our studies of a set of transformants have documented intriguing, construct-associated effects on leaf morphology, and provide important and unexpected insights into the performance of the ‘Hawaii 4’ transformation and regeneration system. Results Following Agrobacterium-mediated transformation of leaf explants with gene constructs carried by Gateway® vectors, plants were regenerated using a modified version of an established ‘Hawaii 4’ protocol. Expanding upon the findings of prior studies, we documented that plantlet regeneration was occurring via a somatic embryogenic rather than an organogenic developmental pathway. Among transformants, several variations in leaf morphology were observed. Unexpectedly, a particular leaf variant type, occurring in ~17% of all regenerants independent of construct type, was found to be attributable to tetraploidy. The tetraploidy-associated alteration in leaf morphology could be differentiated from the leaf morphology of diploid regenerants on the basis of a quantitative ratio of leaf dimensions: B/A, where B is the width of the central leaflet and A is the overall width of the trifoliate leaf. Variant effects on leaf morphology of four different transgenic constructs were also documented, and were in all cases distinguishable from the effects of tetraploidy. Conclusions These results define opportunities to optimize the existing ‘Hawaii 4’ protocol by focusing on treatments that specifically promote somatic embryogenesis. The reported morphological metric and descriptions will guide future transgenic studies using the ‘Hawaii 4’ model system by alerting researchers to the potential occurrence of polyploid regenerants, and to differentiating the effects on leaf morphology due to polyploidy versus transgenic manipulations. Finally, an intriguing spectrum of leaf morphology alterations resulting from manipulation of expressed sequences of uncertain function is documented, providing a foundation for detailed studies of the respective genes and their functional roles. PMID:24418064

  15. A Novel In Vitro Protocol for Inducing Direct Somatic Embryogenesis in Phalaenopsis aphrodite without Taking Explants

    PubMed Central

    Chen, Jen-Tsung

    2014-01-01

    An alternative in vitro protocol for embryo induction directly from intact living seedlings of Phalaenopsis aphrodite subspecies formosana was established in this study. Without the supplementation of plant growth regulators (PGRs), no embryos were obtained from all the seedlings when cultured on the solid medium. In contrast, embryos formed from the seedlings on the 2-layer medium and the 2-step culture system without the use of PGRs. It was found that the age of the seedlings affected embryo induction. The 2-month-old seedlings typically had higher embryogenic responses when compared with the 4-month-old seedlings in the 2-layer medium or 2-step system. For the 2-month-old seedlings, 1?mg/L TDZ resulted in the highest number of embryos at the distal site of the shoot. However, on the leaves' surface, 0.5?mg/L TDZ induced the highest number of embryos. When the 2-month-old seedlings were cultured using the 2-step method at 1?mg/L of TDZ, the highest embryogenic response was obtained, with an average of 44 embryos formed on each seedling. These adventitious embryos were able to convert into plantlets in a PGR-free 1/2 MS medium, and the plantlets had normal morphology and growth. PMID:24963505

  16. LEAFY COTYLEDON1-CASEIN KINASE I-TCP15-PHYTOCHROME INTERACTING FACTOR4 Network Regulates Somatic Embryogenesis by Regulating Auxin Homeostasis1[OPEN

    PubMed Central

    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

  17. Hsp70 and Hsp90 change their expression and subcellular localization after microspore embryogenesis induction in Brassica napus L.

    PubMed

    Seguí-Simarro, J M; Testillano, P S; Risueño, M C

    2003-06-01

    A stress treatment of 32 degrees C for at least 8h was able to change the gametophytic program of the microspore, switching it to embryogenesis in Brassica napus, an interesting model for studying this process in vitro. After induction, some microspores started symmetric divisions and became haploid embryos after a few days, whereas other microspores, not sensitive to induction, followed their original gametophytic development. In this work the distribution and ultrastructural localization of two heat-shock proteins (Hsp70 and Hsp90) throughout key stages before and after embryogenesis induction were studied. Both Hsp proteins are rapidly induced, localizing in the nucleus and the cytoplasm. Immunogold labeling showed changes in the distribution patterns of these proteins, these changes being assessed by a quantitative analysis. Inside the nucleus, Hsp70 was found in association with RNP structures in the interchromatin region and in the nucleolus, whereas nuclear Hsp90 was mostly found in the interchromatin region. For Hsp70, the accumulation after the inductive treatment was accompanied by a reversible translocation from the cytoplasm to the nucleus, in both induced (embryogenic) and noninduced (gametophytic) microspores. However, the translocation was higher in embryogenic microspores, suggesting a possible additional role for Hsp70 in the switch to embryogenesis. In contrast, Hsp90 increase was similar in all microspores, occurring faster than for Hsp70 and suggesting a more specific role for Hsp90 in the stress response. Hsp70 and Hsp90 colocalized in clusters in the cytoplasm and the nucleus, but not in the nucleolus. Results indicated that stress proteins are involved in the process of microspore embryogenesis induction. The differential appearance and distribution of the two proteins and their association at specific stages have been determined between the two systems coexisting in the same culture: embryogenic development (induced cells) and development of gametes (noninduced cells). PMID:12781665

  18. Plant regeneration by somatic embryogenesis from cultured immature embryos of oak (Querem robur L.) and linden (Tilia cordata Mill.).

    PubMed

    Chalupa, V

    1990-11-01

    Embryogenic cultures and somatic embryos were obtained from immature zygotic embryos of oak (Quercus robur L.) cultured on a modified MS medium and WPM containing BAP (1 mg·l(-1)) and GA3 (1 mg·l(-1)) or BAP and IBA. Germination and conversion of oak somatic embryos into plantlets was achieved on WPM containing a reduced concentration of cytokinin. Linden (Tilia cordata Mill.) somatic embryos developed in embryogenic tissues initiated from immature zygotic embryos cultured on a modified MS medium supplemented with 2,4-D (0.3-2.0 mg·l(-1)). Germination of linden somatic embryos and plantlet formation occurred on MS medium containing a low concentration of IBA. Oak and linden plantlets produced from somatic embryos were successfully established in soil. Somatic embryos and plantlets were also regenerated from embryogenic cultures of Quercus petraea and Tilia platyphyllos. PMID:24227064

  19. INDUCTION OF SOMATIC EMBRYOGENESIS IN O'HENRY CULTIVAR OF PEACH (PRUNUS PERSICA)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The peach industry plays an important role in the agricultural economy of the southeastern United States, annually producing 35% of the American peach crop. Peach tree short life (PTSL) syndrome results in the drastic decline in peach tree population and orchard longevity. It prematurely kills trees...

  20. Induction of pluripotency in mouse somatic cells with lineage specifiers.

    PubMed

    Shu, Jian; Wu, Chen; Wu, Yetao; Li, Zhiyuan; Shao, Sida; Zhao, Wenhui; Tang, Xing; Yang, Huan; Shen, Lijun; Zuo, Xiaohan; Yang, Weifeng; Shi, Yan; Chi, Xiaochun; Zhang, Hongquan; Gao, Ge; Shu, Youmin; Yuan, Kehu; He, Weiwu; Tang, Chao; Zhao, Yang; Deng, Hongkui

    2013-05-23

    The reprogramming factors that induce pluripotency have been identified primarily from embryonic stem cell (ESC)-enriched, pluripotency-associated factors. Here, we report that, during mouse somatic cell reprogramming, pluripotency can be induced with lineage specifiers that are pluripotency rivals to suppress ESC identity, most of which are not enriched in ESCs. We found that OCT4 and SOX2, the core regulators of pluripotency, can be replaced by lineage specifiers that are involved in mesendodermal (ME) specification and in ectodermal (ECT) specification, respectively. OCT4 and its substitutes attenuated the elevated expression of a group of ECT genes, whereas SOX2 and its substitutes curtailed a group of ME genes during reprogramming. Surprisingly, the two counteracting lineage specifiers can synergistically induce pluripotency in the absence of both OCT4 and SOX2. Our study suggests a "seesaw model" in which a balance that is established using pluripotency factors and/or counteracting lineage specifiers can facilitate reprogramming. PMID:23706735

  1. Factors influencing somatic embryogenesis, regeneration, and Agrobacterium-mediated transformation of cassava (Manihot esculenta Crantz) cultivar TME14.

    PubMed

    Nyaboga, Evans N; Njiru, Joshua M; Tripathi, Leena

    2015-01-01

    Routine production of large numbers of transgenic plants is required to fully exploit advances in cassava biotechnology and support development of improved germplasm for deployment to farmers. This article describes an improved, high-efficiency transformation protocol for recalcitrant cassava cultivar TME14 preferred in Africa. Factors that favor production of friable embryogenic calli (FEC) were found to be use of DKW medium, crushing of organized embryogenic structures (OES) through 1-2 mm sized metal wire mesh, washing of crushed OES tissues and short exposure of tyrosine to somatic embryos; and transformation efficiency was enhanced by use of low Agrobacterium density during co-cultivation, co-centrifugation of FEC with Agrobacterium, germination of paramomycin resistant somatic embryos on medium containing BAP with gradual increase in concentration and variations of the frequency of subculture of cotyledonary-stage embryos on shoot elongation medium. By applying the optimized parameters, FEC were produced for cassava cultivar TME14 and transformed using Agrobacterium strain LBA4404 harboring the binary vector pCAMBIA2301. About 70-80 independent transgenic lines per ml settled cell volume (SCV) of FEC were regenerated on selective medium. Histochemical GUS assays confirmed the expression of gusA gene in transformed calli, somatic embryos and transgenic plants. The presence and integration of the gusA gene were confirmed by PCR and Southern blot analysis, respectively. RT-PCR analysis of transgenic plants confirmed the expression of gusA gene. This protocol demonstrates significantly enhanced transformation efficiency over existing cassava transformation protocols and could become a powerful tool for functional genomics and transferring new traits into cassava. PMID:26113851

  2. Factors influencing somatic embryogenesis, regeneration, and Agrobacterium-mediated transformation of cassava (Manihot esculenta Crantz) cultivar TME14

    PubMed Central

    Nyaboga, Evans N.; Njiru, Joshua M.; Tripathi, Leena

    2015-01-01

    Routine production of large numbers of transgenic plants is required to fully exploit advances in cassava biotechnology and support development of improved germplasm for deployment to farmers. This article describes an improved, high-efficiency transformation protocol for recalcitrant cassava cultivar TME14 preferred in Africa. Factors that favor production of friable embryogenic calli (FEC) were found to be use of DKW medium, crushing of organized embryogenic structures (OES) through 1–2 mm sized metal wire mesh, washing of crushed OES tissues and short exposure of tyrosine to somatic embryos; and transformation efficiency was enhanced by use of low Agrobacterium density during co-cultivation, co-centrifugation of FEC with Agrobacterium, germination of paramomycin resistant somatic embryos on medium containing BAP with gradual increase in concentration and variations of the frequency of subculture of cotyledonary-stage embryos on shoot elongation medium. By applying the optimized parameters, FEC were produced for cassava cultivar TME14 and transformed using Agrobacterium strain LBA4404 harboring the binary vector pCAMBIA2301. About 70–80 independent transgenic lines per ml settled cell volume (SCV) of FEC were regenerated on selective medium. Histochemical GUS assays confirmed the expression of gusA gene in transformed calli, somatic embryos and transgenic plants. The presence and integration of the gusA gene were confirmed by PCR and Southern blot analysis, respectively. RT-PCR analysis of transgenic plants confirmed the expression of gusA gene. This protocol demonstrates significantly enhanced transformation efficiency over existing cassava transformation protocols and could become a powerful tool for functional genomics and transferring new traits into cassava. PMID:26113851

  3. Development of grapevine somatic embryogenesis using an air-lift bioreactor as an efficient tool in the generation of transgenic plants.

    PubMed

    Tapia, Eduardo; Sequeida, Alvaro; Castro, Alvaro; Montes, Christian; Zamora, Pablo; López, Reinaldo; Acevedo, Fernando; Prieto, Humberto

    2009-01-01

    The grapevine genetic transformation programs have relayed on the use of solid media-based somatic embryogenesis. To reach a high throughput of candidate gene evaluation in 'Thompson Seedless', a semi-automatic system allowing viable transformation of explants was designed. An intermediate procedure using liquid media and agitated flasks was first characterized, leading to reduction in the biomass duplication time of pro-embryogenic (PE) cells from 30 d in dishes to 14 d. The oxygen transfer coefficient value in this system was 213h(-1) at 120rpm and 25 degrees C with a 16/8-h (light/darkness) photoperiod. The scaling-up to the air-lift bioreactor decreased the biomass duplication time of PE cells up to 5.3 d post-inoculation (pi) and an average volumetric productivity of 1.6g/(dxL). Although slight browning was seen in the explants during the phase of 8-14 d pi, no losses in their viability and regenerative capability were observed. Cultured cells showed normal elongation in the transition from heart- to the torpedo-shape and finally to advanced developmental stages, with radicle emergence and whole plant generation. Agrobacterium-mediated transformation of cells was efficiently incorporated after this multiplication process by use of conventional procedures in dishes, allowing the generation of transgenic plantlets confirmed by PCR. PMID:18984020

  4. Endogenous target mimics down-regulate miR160 mediation of ARF10, -16, and -17 cleavage during somatic embryogenesis in Dimocarpus longan Lour

    PubMed Central

    Lin, Yuling; Lai, Zhongxiong; Tian, Qilin; Lin, Lixia; Lai, Ruilian; Yang, Manman; Zhang, Dongmin; Chen, Yukun; Zhang, Zihao

    2015-01-01

    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 (SA) and heat stress. The pri-miR160 was down-regulated in response to SA 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 friable-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 2,4-D 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 eTMs, miR160, and ARF10, -16, and -17 exhibited tissue specificity in ‘Sijimi’ longan vegetative and reproductive organs, but were not significant negatively correlated. These results provide insights into the possible role of the eTM-miR160-ARF10-16-17 pathway in longan somatic embryo development. PMID:26594219

  5. Induction of Embryogenesis in Brassica Napus Microspores Produces a Callosic Subintinal Layer and Abnormal Cell Walls with Altered Levels of Callose and Cellulose

    PubMed Central

    Parra-Vega, Verónica; Corral-Martínez, Patricia; Rivas-Sendra, Alba; Seguí-Simarro, Jose M.

    2015-01-01

    The induction of microspore embryogenesis produces dramatic changes in different aspects of the cell physiology and structure. Changes at the cell wall level are among the most intriguing and poorly understood. In this work, we used high pressure freezing and freeze substitution, immunolocalization, confocal, and electron microscopy to analyze the structure and composition of the first cell walls formed during conventional Brassica napus microspore embryogenesis, and in cultures treated to alter the intracellular Ca2+ levels. Our results revealed that one of the first signs of embryogenic commitment is the formation of a callose-rich, cellulose-deficient layer beneath the intine (the subintinal layer), and of irregular, incomplete cell walls. In these events, Ca2+ may have a role. We propose that abnormal cell walls are due to a massive callose synthesis and deposition of excreted cytoplasmic material, and the parallel inhibition of cellulose synthesis. These features were absent in pollen-like structures and in microspore-derived embryos, few days after the end of the heat shock, where abnormal cell walls were no longer produced. Together, our results provide an explanation to a series of relevant aspects of microspore embryogenesis including the role of Ca2+ and the occurrence of abnormal cell walls. In addition, our discovery may be the explanation to why nuclear fusions take place during microspore embryogenesis. PMID:26635844

  6. MicroRNA390-Directed TAS3 Cleavage Leads to the Production of tasiRNA-ARF3/4 During Somatic Embryogenesis in Dimocarpus longan Lour

    PubMed Central

    Lin, Yuling; Lin, Lixia; Lai, Ruilian; Liu, Weihua; Chen, Yukun; Zhang, Zihao; XuHan, Xu; Lai, Zhongxiong

    2015-01-01

    Trans-acting short-interfering RNAs (tasiRNAs) originate from TAS3 families through microRNA (miRNA) 390-guided cleavage of primary transcripts and target auxin response factors (ARF3/-4), which are involved in the normal development of lateral roots and flowers in plants. However, their roles in embryo development are still unclear. Here, the pathway miR390-TAS3-ARF3/-4 was identified systematically for the first time during somatic embryo development in Dimocarpus longan. We identified the miR390 primary transcript and promoter. The promoter contained cis-acting elements responsive to stimuli such as light, salicylic acid, anaerobic induction, fungal elicitor, circadian control, and heat stress. The longan TAS3 transcript, containing two miR390-binding sites, was isolated; the miR390- guided cleavage site located near the 3? end of the TAS3 transcript was verified. Eight TAS3-tasiRNAs with the 21-nucleotides phase were found among longan small RNA data, further confirming that miR390-directed TAS3 cleavage leads to the production of tasiRNA in longan. Among them, TAS3_5?D5+ and 5?D6+ tasiRNAs were highly abundant, and verified to target ARF3 and -4, implying that miR390-guided TAS3 cleavage with 21-nucleotides phase leading to the production of tasiRNA-ARF is conserved in plants. Pri-miR390 was highly expressed in friable-embryogenic callus (EC), and less expressed in incomplete compact pro-embryogenic cultures, while miR390 showed its lowest expression in EC and highest expression in torpedo-shaped embryos (TEs). DlTAS3 and DlARF4 both exhibited their lowest expressions in EC, and reached their peaks in the globular embryos stage, which were mainly inversely proportional to the expression of miR390, especially at the globular embryos to cotyledonary embryos (CEs) stages. While DlARF3 showed little variation from the EC to TEs stages, and exhibited its lowest expression in the CEs stage. There was a general lack of correlation between the expressions of DlARF3 and miR390. In addition, pri-miR390, DlTAS3, DlARF3 and -4 were up-regulated by 2,4-D in a concentration-dependent manner. They were also preferentially expressed in roots, pulp, and seeds of ‘Sijimi’ longan, implying their extended roles in the development of longan roots and fruit. This study provided insights into a possible role of miR390-tasiRNAs-ARF in plant somatic embryo development.

  7. Recent Advances on Genetic and Physiological Bases of In Vitro Somatic Embryo Formation.

    PubMed

    Altamura, Maria Maddalena; Della Rovere, Federica; Fattorini, Laura; D'Angeli, Simone; Falasca, Giuseppina

    2016-01-01

    Somatic embryogenesis involves a broad repertoire of genes, and complex expression patterns controlled by a concerted gene regulatory network. The present work describes this regulatory network focusing on the main aspects involved, with the aim of providing a deeper insight into understanding the total reprogramming of cells into a new organism through a somatic way. To the aim, the chromatin remodeling necessary to totipotent stem cell establishment is described, as the activity of numerous transcription factors necessary to cellular totipotency reprogramming. The eliciting effects of various plant growth regulators on the induction of somatic embryogenesis is also described and put in relation with the activity of specific transcription factors. The role of programmed cell death in the process, and the related function of specific hemoglobins as anti-stress and anti-death compounds is also described. The tools for biotechnology coming from this information is highlighted in the concluding remarks. PMID:26619858

  8. Comparison of Somatic Embryogenesis?derived Coffee (Coffea arabica L.) Plantlets Regenerated in vitro or ex vitro: Morphological, Mineral and Water Characteristics

    PubMed Central

    BARRY?ETIENNE, D.; BERTRAND, B.; VASQUEZ, N.; ETIENNE, H.

    2002-01-01

    Coffea arabica L. plantlets obtained ex vitro after sowing somatic embryos produced in a bioreactor in horticultural substrate were compared with those obtained in vitro from the same embryo population under conventional culturing conditions on semi?solid media. The intensity and quality of aerial and root system development were compared. Shoot emergence was more efficient in vitro but rooting frequencies were low. In contrast, all ex vitro?regenerated embryos rooted. The cotyledon area of mature embryos produced in a bioreactor positively affected plantlet development when regeneration was carried out ex vitro. Embryos with an intermediate cotyledon area (0·86 cm2) had the highest rates of plant conversion ex vitro (63 %), and also resulted in vigorous plantlets. Mortality was higher in nursery conditions, but better plant development was obtained. The quality of plantlets produced under ex vitro conditions was reflected in better growth of the aerial and root systems, and also by similar morphological, mineral and water status characteristics to seedlings. Unlike roots formed on semi?solid media, those produced in soil were branched, fine (30–50 % had a diameter of less than 0·5 mm) and they bore root hairs. Leaves of plantlets regenerated ex vitro had a histological structure similar to that of seedling leaves, and a lower stomatal density (100 vs. 233 mm–2). Moreover, they were more turgid, as indicated by higher pressure potential (?P) (0·91 vs. 0·30 MPa) and relative water content values (97 vs. 93 %). Furthermore, under in vitro conditions, leaves had larger stomata which were abnormally round and raised. Direct sowing of germinated somatic embryos resulted in the rapid production of vigorous plantlets under ex vitro conditions, whilst removing the need for problematical and costly conventional acclimatization procedures. PMID:12125775

  9. [Induction by mycotoxins of somatic mosaicism in Drosophila and DNA repair in mammalian liver cell cultures].

    PubMed

    Belitski?, G A; Khovanova, E M; Budunova, I V; Sharunich, E G

    1983-07-01

    The genotoxic activity of four mycotoxins has been studied. High level of somatic mutagenesis in imaginal discs of Drosophila melanogaster larvae and DNA repair synthesis in human embryo and adult rat liver cell cultures were inducible only by highly carcinogenic aflatoxin B1. Patulin, a weak direct-action carcinogenic substance, slightly elevated the mutagenesis in somatic cells of Drosophila but did not induce DNA repair synthesis in liver cell cultures. Citrinin that did not exhibit any carcinogenic properties when used alone and stachybotrotoxin with non-reported carcinogenic activity appeared inactive in the test-systems applied. The possibilities of rapid recognition of carcinogenic mycotoxins by detecting their genotoxic properties are discussed. PMID:6409185

  10. Histological and transcript analyses of intact somatic embryos in an elite maize (Zea mays L.) inbred line Y423.

    PubMed

    Liu, Beibei; Su, Shengzhong; Wu, Ying; Li, Ying; Shan, Xiaohui; Li, Shipeng; Liu, Hongkui; Dong, Haixiao; Ding, Meiqi; Han, Junyou; Yuan, Yaping

    2015-07-01

    Intact somatic embryos were obtained from an elite maize inbred line Y423, bred in our laboratory. Using 13-day immature embryos after self-pollination as explants, and after 4-5 times subculture, a large number of somatic embryos were detected on the surface of the embryonic calli on the medium. The intact somatic embryos were transferred into the differential medium, where the plantlets regenerated with shoots and roots forming simultaneously. Histological analysis and scanning electron micrographs confirmed the different developmental stages of somatic embryogenesis, including globular-shaped embryo, pear-shaped embryo, scutiform embryo, and mature embryo. cDNA-amplified fragment length polymorphism (cDNA-AFLP) was used for comparative transcript profiling between embryogenic and non-embryogenic calli of a new elite maize inbred line Y423 during somatic embryogenesis. Differentially expressed genes were cloned and sequenced. Gene Ontology analysis of 117 candidate genes indicated their involvement in cellular component, biological process and molecular function. Nine of the candidate genes were selected. The changes in their expression levels during embryo induction and regeneration were analyzed in detail using quantitative real-time PCR. Two full-length cDNA sequences, encoding ZmSUF4 (suppressor of fir 4-like protein) and ZmDRP3A (dynamin-related protein), were cloned successfully from intact somatic embryos of the elite inbred maize line Y423. Here, a procedure for maize plant regeneration from somatic embryos is described. Additionally, the possible roles of some of these genes during the somatic embryogenesis has been discussed. This study is a systematic analysis of the cellular and molecular mechanism during the formation of intact somatic embryos in maize. PMID:25931320

  11. Bioreactors for Plant Embryogenesis and Beyond.

    PubMed

    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. PMID:26619865

  12. Induction of somatic instability in stable yellow leaf mutant of rice by ion beam irradiation

    NASA Astrophysics Data System (ADS)

    Maekawa, M.; Hase, Y.; Shikazono, N.; Tanaka, A.

    2003-05-01

    Any class II type active transposons have not been discovered in rice though transposon (mobile element) is very useful for gene isolation in several plant species. In order to capture somatic instability induced by an endogenous active transposon in rice, stable yellow leaf plants derived from a variegated yellow leaf ( yl-v) mutant found in F2 of a cross between distantly related rice varieties were irradiated with carbon and helium ion beams. In M1 plants derived from the seeds irradiated with 50 Gy of 220 MeV carbon ions, a variegated yl plant was generated and this plant showed small or large sectors in leaves expanded later. Most of panicle-row M2 lines segregated into variegated and stable yl plants. In total, the ratio of variegated to stable yl plants was 3:1, suggesting that clear variegation observed on M1 plants might be caused by activation of a cryptic inactive autonomous element by carbon ion beam irradiation.

  13. Vitamin C deficiency improves somatic embryo development through distinct gene regulatory networks in Arabidopsis

    PubMed Central

    Becker, Michael G.; Chan, Ainsley; Mao, Xingyu; Girard, Ian J.; Lee, Samantha; Elhiti, Mohamed; Stasolla, Claudio; Belmonte, Mark F.

    2014-01-01

    Changes in the endogenous ascorbate redox status through genetic manipulation of cellular ascorbate levels were shown to accelerate cell proliferation during the induction phase and improve maturation of somatic embryos in Arabidopsis. Mutants defective in ascorbate biosynthesis such as vtc2-5 contained ~70 % less cellular ascorbate compared with their wild-type (WT; Columbia-0) counterparts. Depletion of cellular ascorbate accelerated cell division processes and cellular reorganization and improved the number and quality of mature somatic embryos grown in culture by 6-fold compared with WT tissues. To gain insight into the molecular mechanisms underlying somatic embryogenesis (SE), we profiled dynamic changes in the transcriptome and analysed dominant patterns of gene activity in the WT and vtc2-5 lines across the somatic embryo culturing process. Our results provide insight into the gene regulatory networks controlling SE in Arabidopsis based on the association of transcription factors with DNA sequence motifs enriched in biological processes of large co-expressed gene sets. These data provide the first detailed account of temporal changes in the somatic embryo transcriptome starting with the zygotic embryo, through tissue dedifferentiation, and ending with the mature somatic embryo, and impart insight into possible mechanisms for the improved culture of somatic embryos in the vtc2-5 mutant line. PMID:25151615

  14. Somatic Crossing over in GLYCINE MAX (L.) Merrill: Effect of Some Inhibitors of DNA Synthesis on the Induction of Somatic Crossing over and Point Mutations.

    PubMed

    Vig, B K

    1973-04-01

    Glycine max (soybean) is the only known higher plant with a definitely established occurrence of somatic crossing over. This material lends itself to the analysis of somatic crossing over, gross chromosomal aberrations and mutations, all of which may be induced by the same treatment of the mutagen given to seeds. This is made possible because gene Y(11) for chlorophyll development in the variety L65-1237 is incompletely dominant over its allele y(11), so that twin or double spots composed of a dark green (Y(11)Y(11)) and a yellow (y(11)y(11)) component can be observed adjacent to and as mirror images of each other on the light green Y(11)y(11) leaves in the areas of complementary exchange for these genes. Lack of growth of either component of this double spot as well as several types of chromosomal disturbances give rise to single spots resembling phenotypes of y(11)y(11) or Y(11)Y(11) leaves. Point mutations can be studied by looking for green sectors originating from Y(11)y(11) genotype on the y(11)y(11) plants. Seeds obtained from heterozygous plants were treated with caffeine, cytosine arabinoside, actinomycin D and 5-fluoro-deoxyuridine, all known inhibitors of DNA synthesis, and puromycin, an inhibitor of synthesis of proteins. The treatments with caffeine and actinomycin D increased the frequency of somatic crossing over as measured by the frequency of double spots on Y(11)y(11) leaves, but cytosine arabinoside, 5-fluorodeoxyuridine and puromycin did not. Thus somatic crossing over was induced only by those chemicals which are known to allow rejoining of chromosomes, thereby suggesting a correlation between the two phenomena. These observations indicate that it is not the mere inhibition of DNA synthesis, but some rather more specific event in DNA repair which is responsible for complementary exchanges. Some of these results differ from studies carried out with fungi. The main effect of all chemicals tested, except caffeine and actinomycin D, was inferred to be the production of deletions in Y(11)y(11) plants which raised the frequency of single (dark green or yellow) spots relative to the doubles. Caffeine was the only chemical which constantly increased the frequency of specific point mutations. In the control material, the great majority of spots are found on the upper surface of the leaf. This picture could not be changed in any of the treated materials, thus indicating uniform resistance of spongy mesophyll tissue to the mutagens applied. PMID:17248598

  15. Somatic Crossing over in GLYCINE MAX (L.) Merrill: Effect of Some Inhibitors of DNA Synthesis on the Induction of Somatic Crossing over and Point Mutations

    PubMed Central

    Vig, B. K.

    1973-01-01

    Glycine max (soybean) is the only known higher plant with a definitely established occurrence of somatic crossing over. This material lends itself to the analysis of somatic crossing over, gross chromosomal aberrations and mutations, all of which may be induced by the same treatment of the mutagen given to seeds. This is made possible because gene Y11 for chlorophyll development in the variety L65-1237 is incompletely dominant over its allele y11, so that twin or double spots composed of a dark green (Y11Y11) and a yellow (y11y11) component can be observed adjacent to and as mirror images of each other on the light green Y11y11 leaves in the areas of complementary exchange for these genes. Lack of growth of either component of this double spot as well as several types of chromosomal disturbances give rise to single spots resembling phenotypes of y11y11 or Y11Y11 leaves. Point mutations can be studied by looking for green sectors originating from Y11y11 genotype on the y11y11 plants. Seeds obtained from heterozygous plants were treated with caffeine, cytosine arabinoside, actinomycin D and 5-fluoro-deoxyuridine, all known inhibitors of DNA synthesis, and puromycin, an inhibitor of synthesis of proteins. The treatments with caffeine and actinomycin D increased the frequency of somatic crossing over as measured by the frequency of double spots on Y11y11 leaves, but cytosine arabinoside, 5-fluorodeoxyuridine and puromycin did not. Thus somatic crossing over was induced only by those chemicals which are known to allow rejoining of chromosomes, thereby suggesting a correlation between the two phenomena. These observations indicate that it is not the mere inhibition of DNA synthesis, but some rather more specific event in DNA repair which is responsible for complementary exchanges. Some of these results differ from studies carried out with fungi. The main effect of all chemicals tested, except caffeine and actinomycin D, was inferred to be the production of deletions in Y11y11 plants which raised the frequency of single (dark green or yellow) spots relative to the doubles. Caffeine was the only chemical which constantly increased the frequency of specific point mutations. In the control material, the great majority of spots are found on the upper surface of the leaf. This picture could not be changed in any of the treated materials, thus indicating uniform resistance of spongy mesophyll tissue to the mutagens applied. PMID:17248598

  16. Dying with Style: Death Decision in Plant Embryogenesis.

    PubMed

    Huang, Shuanglong; Mira, Mohamed M; Stasolla, Claudio

    2016-01-01

    Embryogenesis is a fascinating event during the plant life cycle encompassing several steps whereby the zygote develops into a fully developed embryo which, in angiosperms, is composed of an axis separating the apical meristems, and two cotyledons. Recapitulation of embryogenesis can also occur in vitro through somatic embryogenesis, where somatic cells are induced to form embryos, and androgenesis, in which embryos originate from immature male gametophytes. Besides cell division and differentiation, embryo patterning in vivo and in vitro requires the dismantling and selective elimination of cells and tissues via programmed cell death (PCD). While the manifestation of the death program has long been acknowledged in vivo, especially in relation to the elimination of the suspensor during the late phases of embryo development, PCD during in vitro embryogenesis has only been described in more recent years. Independent studies using the gymnosperm Norway spruce and the angiosperm maize have shown that the death program is crucial for the proper formation and further development of immature somatic embryos. This chapter summarizes the recent advances in the field of PCD during embryogenesis and proposes novel regulatory mechanisms activating the death program in plants. PMID:26619860

  17. Rapid tumor induction in zebrafish by TALEN-mediated somatic inactivation of the retinoblastoma1 tumor suppressor rb1

    PubMed Central

    Solin, Staci L.; Shive, Heather R.; Woolard, Kevin D.; Essner, Jeffrey J.; McGrail, Maura

    2015-01-01

    Investigating the in vivo role of tumor suppressor genes in cancer is technically challenging due to their essential requirement during early animal development. To address this bottleneck, we generated genetic mosaic adult zebrafish using TALEN genome editing and demonstrate somatic inactivation of the tumor suppressor retinoblastoma1 (rb1) induces tumorigenesis at high frequency. 11–33% of 1-cell stage embryos injected with TALEN mRNAs targeting rb1 exon 2 or 3 develop tumors beginning as early as 3.5 months of age. Lesions predominantly arise in the brain and show features of neuroectodermal-like and glial-like tumors. Mutant allele analysis is consistent with tumor initiation due to somatic inactivation of rb1, revealing a conserved role for rb1 in tumor suppression across vertebrates. In contrast to genetic mosaics, heterozygous rb1?/+ adults show no evidence of neoplasia, while homozygous mutant rb1?/? are larval lethal. This is the first demonstration that somatic inactivation of a tumor suppressor causes cancer in zebrafish, and highlights the utility of site-specific nucleases to create genetic mosaic zebrafish for tumor suppressor gene discovery. Somatic inactivation with site-directed nucleases in zebrafish presents a rapid and scalable strategy to study tumor suppressor gene function in cancer. PMID:26345384

  18. Rapid tumor induction in zebrafish by TALEN-mediated somatic inactivation of the retinoblastoma1 tumor suppressor rb1.

    PubMed

    Solin, Staci L; Shive, Heather R; Woolard, Kevin D; Essner, Jeffrey J; McGrail, Maura

    2015-01-01

    Investigating the in vivo role of tumor suppressor genes in cancer is technically challenging due to their essential requirement during early animal development. To address this bottleneck, we generated genetic mosaic adult zebrafish using TALEN genome editing and demonstrate somatic inactivation of the tumor suppressor retinoblastoma1 (rb1) induces tumorigenesis at high frequency. 11-33% of 1-cell stage embryos injected with TALEN mRNAs targeting rb1 exon 2 or 3 develop tumors beginning as early as 3.5 months of age. Lesions predominantly arise in the brain and show features of neuroectodermal-like and glial-like tumors. Mutant allele analysis is consistent with tumor initiation due to somatic inactivation of rb1, revealing a conserved role for rb1 in tumor suppression across vertebrates. In contrast to genetic mosaics, heterozygous rb1-/+ adults show no evidence of neoplasia, while homozygous mutant rb1-/- are larval lethal. This is the first demonstration that somatic inactivation of a tumor suppressor causes cancer in zebrafish, and highlights the utility of site-specific nucleases to create genetic mosaic zebrafish for tumor suppressor gene discovery. Somatic inactivation with site-directed nucleases in zebrafish presents a rapid and scalable strategy to study tumor suppressor gene function in cancer. PMID:26345384

  19. A Comparison of In Vitro and In Vivo Asexual Embryogenesis.

    PubMed

    Hand, Melanie L; de Vries, Sacco; Koltunow, Anna M G

    2016-01-01

    In plants, embryogenesis generally occurs through the sexual process of double fertilization, which involves a haploid sperm cell fusing with a haploid egg cell to ultimately give rise to a diploid embryo. Embryogenesis can also occur asexually in the absence of fertilization, both in vitro and in vivo. Somatic or gametic cells are able to differentiate into embryos in vitro following the application of plant growth regulators or stress treatments. Asexual embryogenesis also occurs naturally in some plant species in vivo, from either ovule cells as part of a process defined as apomixis, or from somatic leaf tissue in other species. In both in vitro and in vivo asexual embryogenesis, the embryo precursor cells must attain an embryogenic fate without the act of fertilization. This review compares the processes of in vitro and in vivo asexual embryogenesis including what is known regarding the genetic and epigenetic regulation of each process, and considers how the precursor cells are able to change fate and adopt an embryogenic pathway. PMID:26619856

  20. Oocyte induction of EGF responsiveness in somatic cells is associated with the acquisition of porcine oocyte developmental competence.

    PubMed

    Ritter, Lesley J; Sugimura, Satoshi; Gilchrist, Robert B

    2015-06-01

    Oocytes progressively acquire the competence to support embryo development as oogenesis proceeds with ovarian folliculogenesis. The objectives of this study were to investigate oocyte-secreted factor (OSF) participation in the development of somatic cell epidermal growth factor (EGF) responsiveness associated with oocyte developmental competence. A well-established porcine model was employed using oocytes from small (<4 mm) vs medium sized (>4 mm) antral follicles, representing low vs moderate developmental competence, respectively. Cumulus-oocyte complexes (COCs) were treated in vitro with inducers of oocyte maturation, and cumulus cell functions and oocyte developmental competence were assessed. COCs from small follicles responded to FSH but, unlike COCs from larger follicles, were incapable of responding to EGF family growth factors known to mediate oocyte maturation in vivo, exhibiting perturbed cumulus expansion and expression of associated transcripts (HAS2 and TNFAIP6). Low and moderate competence COCs expressed equivalent levels of EGF receptor (EGFR) mRNA; however, the former had less total EGFR protein leading to failed activation of phospho-EGFR and phospho-ERK1/2, despite equivalent total ERK1/2 protein levels. Native OSFs from moderate, but not from low, competence oocytes established EGF responsiveness in low competence COCs. Four candidate recombinant OSFs failed to mimic the actions of native OSFs in regulating cumulus expansion. Treatment with OSFs and EGF enhanced oocyte competence but only of the low competence COCs. These data suggest that developmental acquisition by the oocyte of capacity to regulate EGF responsiveness in the oocyte's somatic cells is a major milestone in the oocyte's developmental program and contributes to coordinated oocyte and somatic cell development. PMID:25849729

  1. Systems Biology of Embryogenesis

    PubMed Central

    Edelman, Lucas B.; Chandrasekaran, Sriram; Price, Nathan D.

    2010-01-01

    The development of a complete organism from a single cell involves extraordinarily complex orchestration of biological processes that vary intricately across space and time. Systems biology seeks to describe how all elements of a biological system interact in order to understand, model, and ultimately predict aspects of emergent biological processes. Embryogenesis represents an extraordinary opportunity – and challenge – for the application of systems biology. Systems approaches have already been used successfully to study various aspects of development, from complex intracellular networks to 4D models of organogenesis. Going forward, great advancements and discoveries can be expected from systems approaches applied to embryogenesis and developmental biology. PMID:20003850

  2. Cyanogenesis in somatic embryos and plantlets of cassava (Manihot esculenta Crantz)

    E-print Network

    Yeoh, Hock Hin

    Cyanogenesis in somatic embryos and plantlets of cassava (Manihot esculenta Crantz) Tessy Joseph cyclic somatic embryogenesis and plant regeneration for the cassava variety PRC 60a. Linamarin content. This system would be useful for investigating cyanogenesis in cassava. # 1999 Society of Chemical Industry

  3. Abstract Soybean [Glycine max (L.) Merrill] somatic embryos of the cultivar Jack underwent histodifferentia-

    E-print Network

    Parrott, Wayne

    Abstract Soybean [Glycine max (L.) Merrill] somatic embryos of the cultivar Jack underwent growth occur (Merkle et al. 1995). Germination and conversion of soybean somatic embryos usually do of a simple and more rapid protocol for soybean so- matic embryogenesis could accelerate efficient recovery

  4. Genetic variation in somatic embryogenesis of Rosa Hybrida L. 

    E-print Network

    Burrell, Anna Mildred

    2004-09-30

    An in vitro technique was adapted for screening the ability of Rosa hybrida L. genotypes to form embryogenic callus to elucidate the inheritance of this ability. Filament and leaf petiole explants of modern rose cultivars ...

  5. THE REGENERATION OF BLACK GRAMA PLANTS VIA SOMATIC EMBRYOGENESIS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seeds of Bouteloua eropida, (Torr.) Torr. were surface disinfested and germinated on a carbon mineral rich medium. Callus was initiated from embryonic shoots excised from the roots on auxin supplemented medium. After callus multiplication, embryos were induced from callus. They developed into nor...

  6. From Somatic Embryo to Synthetic Seed in Citrus spp. Through the Encapsulation Technology.

    PubMed

    Micheli, Maurizio; Standardi, Alvaro

    2016-01-01

    In vitro propagation by somatic embryogenesis represents an efficient alternative method to produce high-quality and healthy plants in Citrus species. The regenerated somatic embryos need protection from mechanical damages during manipulation and transport, as well as nutritive support for their evolution in plantlets after sowing. The encapsulation technology allows to obtain synthetic seeds by covering somatic embryos with a gel of calcium alginate enriched by nutrients. This chapter describes the procedure for producing synthetic seeds containing somatic embryos from different Citrus genotypes. PMID:26619885

  7. Somatic embryo mediated mass production of Catharanthus roseus in culture vessel (bioreactor) – A comparative study

    PubMed Central

    Mujib, A.; Ali, Muzamil; Isah, Tasiu; Dipti

    2014-01-01

    The purpose of this study was to evaluate and compare the use of liquid and solid Murashige and Skoog (MS) medium in different culture vessels for mass production of Catharanthus roseus, an important source of anticancerous compounds, vincristine and vinblastine. Three media conditions i.e. agar-solidified medium (S), liquid medium in agitated conical flask (L) and growtek bioreactor (B) were used. Rapid propagation was achieved through in vitro somatic embryogenesis pathway. The process of embryogenesis has been categorized into induction, proliferation, maturation and germination stages. All in vitro embryogenesis stages were conducted by withdrawing spent liquid medium and by adding fresh MS medium. In optimized 4.52 ?M 2,4-D added MS, the callus biomass growth was low in solid (1.65 g) compared to liquid medium in agitated conical flask (1.95 g) and in bioreactor (2.11 g). The number of normal somatic embryos was more in solid medium (99.75/50 mg of callus mass) compared to liquid medium used in conical flask (83.25/callus mass) and growtek bioreactor (84.88/callus mass). The in vitro raised embryos maturated in GA3 (2.60 ?M) added medium; and in bioreactor the embryo growth was high, a maximum length of 9.82 mm was observed at the end of four weeks. These embryos germinated into seedlings in BAP (2.22 ?M) added medium and the embryo germination ability was more (59.41%) in bioreactor compared to liquid medium in conical flask (55.5%). Shoot length (11.25 mm) was also high in bioreactor compared to agitated conical flask. The liquid medium used in agitated conical flask and bioreactor increased seedling production efficiency, at the same time it also reduced plant recovery time. The embryo generated plants grew normally in outdoor conditions. The exploitation of medium to large culture vessel or bioreactor may make the process more efficient in getting large number of Catharanthus plant as it is the only source of anti-cancerous alkaloids, vincristine and vinblastine. PMID:25313279

  8. Transcript profiling and identification of molecular markers for early microspore embryogenesis in Brassica napus.

    PubMed

    Malik, Meghna R; Wang, Feng; Dirpaul, Joan M; Zhou, Ning; Polowick, Patricia L; Ferrie, Alison M R; Krochko, Joan E

    2007-05-01

    Isolated microspores of Brassica napus are developmentally programmed to form gametes; however, microspores can be reprogrammed through stress treatments to undergo appropriate divisions and form embryos. We are interested in the identification and isolation of factors and genes associated with the induction and establishment of embryogenesis in isolated microspores. Standard and normalized cDNA libraries, as well as subtractive cDNA libraries, were constructed from freshly isolated microspores (0 h) and microspores cultured for 3, 5, or 7 d under embryogenesis-inducing conditions. Library comparison tools were used to identify shifts in metabolism across this time course. Detailed expressed sequence tag analyses of 3 and 5 d cultures indicate that most sequences are related to pollen-specific genes. However, semiquantitative and real-time reverse transcription-polymerase chain reaction analyses at the initial stages of embryo induction also reveal expression of embryogenesis-related genes such as BABYBOOM1, LEAFY COTYLEDON1 (LEC1), and LEC2 as early as 2 to 3 d of microspore culture. Sequencing results suggest that embryogenesis is clearly established in a subset of the microspores by 7 d of culture and that this time point is optimal for isolation of embryo-specific expressed sequence tags such as ABSCISIC ACID INSENSITIVE3, ATS1, LEC1, LEC2, and FUSCA3. Following extensive polymerase chain reaction-based expression profiling, 16 genes were identified as unequivocal molecular markers for microspore embryogenesis in B. napus. These molecular marker genes also show expression during zygotic embryogenesis, underscoring the common developmental pathways that function in zygotic and gametic embryogenesis. The quantitative expression values of several of these molecular marker genes are shown to be predictive of embryogenic potential in B. napus cultivars (e.g. 'Topas' DH4079, 'Allons,' 'Westar,' 'Garrison'). PMID:17384168

  9. Proliferation, Maturation and Germination of Castanea sativa Mill. Somatic Embryos Originated from Leaf Explants

    PubMed Central

    CORREDOIRA, E.; BALLESTER, A.; VIEITEZ, A. M.

    2003-01-01

    Experiments were performed to determine the influence of proliferation medium on the maintenance of embryogenic competence and on repetitive embryogenesis in Castanea sativa Mill. somatic embryos derived from leaf explants. Somatic embryo proliferation was carried out by both direct secondary embryogenesis and by the culture of nodular callus tissue originated from cotyledons of somatic embryos. Both systems led to the production of cotyledonary somatic embryos on Murashige and Skoog proliferation medium supplemented with 0·1 mg l–1 benzyladenine and 0·1 mg l–1 naphthaleneacetic acid. Carbon source and concentration had a marked influence on maturation and subsequent germination ability of chestnut somatic embryos. Plantlet conversion was achieved in embryos matured on media with 6 % sucrose, and on 3 or 6 % maltose, whereas mean shoot length, root length and leaf number of produced plants were not significantly affected by these maturation media. Overall, the best results were obtained with 3 % maltose?matured somatic embryos, giving rise to 6 % plant recovery in addition to 33 % of embryos exhibiting only shoot development. The application of a 2?month cold treatment at 4 °C to somatic embryos matured on medium with 3 % maltose was necessary for achieving plant conversion, while partial desiccation did not appear to influence this response. A total of 39 % of embryos eventually produced plants either through conversion to plantlets or indirectly through rooting of shoots. Shoots formed by somatic embryos could be excised, multiplied and rooted following the micropropagation procedures previously developed for chestnut. PMID:12763755

  10. SYCHRONIZED SOMATIC EMBRYO DEVELOPMENT IN EMBRYOGENIC SUSPENSIONS OF GRAPEVINE (MUSCADINIA ROTUNDIFOLIA SMALL AND VITIS VINIFERA L.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The full advantages of somatic embryogenesis as a regeneration system and essential model for performing functional genomics studies and understanding molecular aspect of the ontogenesis of higher plants are demonstrated only in high-frequency, synchronous embryogenic system in liquid culture. In t...

  11. vasa and piwi are required for mitotic integrity in early embryogenesis in the spider Parasteatoda tepidariorum.

    PubMed

    Schwager, Evelyn E; Meng, Yue; Extavour, Cassandra G

    2015-06-15

    Studies in vertebrate and invertebrate model organisms on the molecular basis of primordial germ cell (PGC) specification have revealed that metazoans can specify their germ line either early in development by maternally transmitted cytoplasmic factors (inheritance), or later in development by signaling factors from neighboring tissues (induction). Regardless of the mode of PGC specification, once animal germ cells are specified, they invariably express a number of highly conserved genes. These include vasa and piwi, which can play essential roles in any or all of PGC specification, development, or gametogenesis. Although the arthropods are the most speciose animal phylum, to date there have been no functional studies of conserved germ line genes in species of the most basally branching arthropod clade, the chelicerates (which includes spiders, scorpions, and horseshoe crabs). Here we present the first such study by using molecular and functional tools to examine germ line development and the roles of vasa and piwi orthologues in the common house spider Parasteatoda (formerly Achaearanea) tepidariorum. We use transcript and protein expression patterns of Pt-vasa and Pt-piwi to show that primordial germ cells (PGCs) in the spider arise during late embryogenesis. Neither Pt-vasa nor Pt-piwi gene products are localized asymmetrically to any embryonic region before PGCs emerge as paired segmental clusters in opisthosomal segments 2-6 at late germ band stages. RNA interference studies reveal that both genes are required maternally for egg laying, mitotic progression in early embryos, and embryonic survival. Our results add to the growing body of evidence that vasa and piwi can play important roles in somatic development, and provide evidence for a previously hypothesized conserved role for vasa in cell cycle progression. PMID:25257304

  12. Influence of growth regulators on callogenesis and somatic embryo development in date palm (Phoenix dactylifera L.) Sahelian cultivars.

    PubMed

    Sané, Djibril; Aberlenc-Bertossi, Frédérique; Diatta, Léopold Ibrahima Djitiningo; Guèye, Badara; Daher, Abdourahman; Sagna, Maurice; Duval, Yves; Borgel, Alain

    2012-01-01

    This study provides a physiological analysis of somatic embryogenesis in four elite cultivars of date palms: Ahmar, Amsekhsi, Tijib, and Amaside, from the initial callogenesis to establishment and proliferation of embryogenic suspension cultures. Somatic embryos development and in vitro plants rooting were also studied. For each step, auxins and cytokinins concentrations were optimised. The primary callogenesis from leaf explants of seedlings appeared highly dependent on genotype. Ahmar (80%) and Amsekhsi (76%) appeared highly callogenic, whereas Tijib (10%) and Amaside (2%) produced low amounts of calluses. 2,4-Dichlorophenoxyacetic acid appeared favorable to the induction of primary callogenesis and its effect was enhanced by the addition of benzyl adenine or adenine sulfate. Secondary friable calli obtained from chopped granular calli were used to initiate embryogenic cell suspensions in media supplied with 2,4-dichlorophenoxyacetic acid. Suspension cultures showed a growth rate of fourfold after four subcultures in presence of 2,4-dichlorophenoxyacetic acid 2 mg/L. Our results showed that a seven-day transitory treatment with benzyl adenine 0,5 mg/L was necessary to optimize embryos development. Naphthalene acetic acid induced the development of primary orthogravitropic roots during embryos germination. The comparison with cytofluorometry of nuclear DNA amounts showed no significant difference in ploidy level between regenerated plants and seedlings. PMID:22629211

  13. Scriptaid Treatment Decreases DNA Methyltransferase 1 Expression by Induction of MicroRNA-152 Expression in Porcine Somatic Cell Nuclear Transfer Embryos

    PubMed Central

    Liang, Shuang; Zhao, Ming-Hui; Choi, Jeong-woo; Kim, Nam-Hyung; Cui, Xiang-Shun

    2015-01-01

    Abnormal epigenetic reprogramming of donor nuclei after somatic cell nuclear transfer (SCNT) is thought to be the main cause of low cloning efficiencies. A growing body of evidence has demonstrated a positive role of Scriptaid, a histone deacetylase inhibitor (HDACi) that belongs to an existing class of hydroxamic acid-containing HDACis, on the development competence of cloned embryos in many species. The present study investigated the effects of Scriptaid on the development of porcine SCNT embryos in vitro and its mechanism. Treatment with 300 or 500 nM Scriptaid for 20 h after activation significantly increased the percentage of SCNT embryos that developed to the blastocyst stage and the total number of cells per blastocyst and significantly decreased the percentage of apoptotic cells in blastocysts. Scriptaid treatment significantly increased the level of histone H3 acetylated at K9 and the conversion of 5-methylcytosine into 5-hydroxymethylcytosine and significantly decreased the level of histone H3 trimethylated at K9 at the pronuclear stage. As a potential mechanism for the DNA methylation changes, our results showed that the expression of DNA methyltransferase 1 was frequently down-regulated in Scriptaid-treated embryos in comparison with untreated embryos and was inversely correlated to endogenous microRNA-152 (miR-152). Taken together, these findings illustrated a crucial functional crosstalk between miR-152 and DNMT1. Meanwhile, mRNA and protein levels of POU5F1 and CDX2 were increased in Scriptaid-treated embryos. mRNA levels of Caspase3, and Bax were significantly decreased and that of Bcl-xL was significantly increased in Scriptaid-treated embryos. In conclusion, these observations would contribute to uncover the nuclear reprogramming mechanisms underlying the effects of Scriptaid on the improvement of porcine SCNT embryos. PMID:26261994

  14. Metabolite profiling of somatic embryos of Cyclamen persicum in comparison to zygotic embryos, endosperm, and testa

    PubMed Central

    Winkelmann, Traud; Ratjens, Svenja; Bartsch, Melanie; Rode, Christina; Niehaus, Karsten; Bednarz, Hanna

    2015-01-01

    Somatic embryogenesis has been shown to be an efficient in vitro plant regeneration system for many crops such as the important ornamental plant Cyclamen persicum, for which this regeneration pathway of somatic embryogenesis is of interest for the vegetative propagation of parental lines as well as elite plants. However, somatic embryogenesis is not commercially used in many crops due to several unsolved problems, such as malformations, asynchronous development, deficiencies in maturation and germination of somatic embryos. In contrast, zygotic embryos in seeds develop and germinate without abnormalities in most cases. Instead of time-consuming and labor-intensive experiments involving tests of different in vitro culture conditions and plant growth regulator supplements, we follow a more directed approach. Zygotic embryos served as a reference and were compared to somatic embryos in metabolomic analyses allowing the future optimization of the in vitro system. The aims of this study were to detect differences in the metabolite profiles of torpedo stage somatic and zygotic embryos of C. persicum. Moreover, major metabolites in endosperm and testa were identified and quantified. Two sets of extracts of two to four biological replicates each were analyzed. In total 52 metabolites were identified and quantified in the different tissues. One of the most significant differences between somatic and zygotic embryos was that the proline concentration in the zygotic embryos was about 40 times higher than that found in somatic embryos. Epicatechin, a scavenger for reactive oxygen species, was found in highest abundance in the testa. Sucrose, the most abundant metabolite was detected in significantly higher concentrations in zygotic embryos. Also, a yet unknown trisaccharide, was significantly enriched in zygotic embryos. PMID:26300898

  15. Hemoglobin Control of Cell Survival/Death Decision Regulates in Vitro Plant Embryogenesis1[W][OPEN

    PubMed Central

    Huang, Shuanglong; Hill, Robert D.; Wally, Owen S.D.; Dionisio, Giuseppe; Ayele, Belay T.; Jami, Sravan Kumar; Stasolla, Claudio

    2014-01-01

    Programmed cell death (PCD) in multicellular organisms is a vital process in growth, development, and stress responses that contributes to the formation of tissues and organs. Although numerous studies have defined the molecular participants in apoptotic and PCD cascades, successful identification of early master regulators that target specific cells to live or die is limited. Using Zea mays somatic embryogenesis as a model system, we report that the expressions of two plant hemoglobin (Hb) genes (ZmHb1 and ZmHb2) regulate the cell survival/death decision that influences somatic embryogenesis through their cell-specific localization patterns. Suppression of either of the two ZmHbs is sufficient to induce PCD through a pathway initiated by elevated NO and Zn2+ levels and mediated by production of reactive oxygen species. The effect of the death program on the fate of the developing embryos is dependent on the localization patterns of the two ZmHbs. During somatic embryogenesis, ZmHb2 transcripts are restricted to a few cells anchoring the embryos to the subtending embryogenic tissue, whereas ZmHb1 transcripts extend to several embryonic domains. Suppression of ZmHb2 induces PCD in the anchoring cells, allowing the embryos to develop further, whereas suppression of ZmHb1 results in massive PCD, leading to abortion. We conclude that regulation of the expression of these ZmHbs has the capability to determine the developmental fate of the embryogenic tissue during somatic embryogenesis through their effect on PCD. This unique regulation might have implications for development and differentiation in other species. PMID:24784758

  16. High Efficiency Somatic Embrogenesis and Plant Regeneration in Suspension Cultures of an Ornamental Ginger Hybrid (Hedychium muluense x cv ‘Starburst’)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Plants were successfully regenerated via somatic embryogenesis from shoot apex-derived callus of an ornamental ginger hybrid, Hedychium muluense x cv ‘Starburst’. H. muluense is a dwarf species and ‘Starburst’ is a hybrid cultivar with white and very fragrant flowers in a circular, wheel-like arrang...

  17. Epigenetic and hormonal profile during maturation of Quercus Suber L. somatic embryos.

    PubMed

    Pérez, Marta; Viejo, Marcos; LaCuesta, Maite; Toorop, Peter; Cañal, María Jesús

    2014-09-17

    Somatic embryogenesis is a powerful alternative to conventional mass propagation of Quercus suber L. However, poor quality and incomplete maturation of somatic embryos restrict any application. Given that epigenetic and hormonal control govern many developmental stages, including maturation of zygotic embryos, global DNA methylation and abscisic acid (ABA) were analyzed during development and maturation of cork oak somatic embryos. Our results indicated that development of somatic embryos concurred with a decrease in 5-mdC. In contrast, endogenous ABA content showed a transient increase with a peak in immature E2 embryos denoting the onset of the maturation phase. A cold stratification phase was necessary for embryos to acquire germination ability, which coincided with a significant decrease in 5-mdC and ABA content. Immunohistochemical analyses showed that there was a specific spatial-temporal regulation during embryogenesis, particularly after the cold treatment. The acquisition of germination capacity concurred with a general low 5-mdC signal in the root meristem, while retention of the 5-mdC signal was mainly located in the shoot meristem and provascular tissues. Conversely, ABA immunolocalization was mainly located in the root and shoot apical meristems. Furthermore, a strong decrease in the ABA signal was observed in the root cap after the stratification treatment suggesting a role for the root cap during development of somatic embryos. These results suggest that, in addition to ABA, epigenetic control appears to play an important role for the correct maturation and subsequent germination of cork oak somatic embryos. PMID:25462078

  18. Somatic symptom disorder

    MedlinePLUS

    ... related disorders; Somatization disorder; Somatiform disorders; Briquet syndrome; Illness anxiety disorder ... a history of abuse. SSD is similar to illness anxiety disorder . This is when a person is ...

  19. Microspore-derived embryogenesis in pepper (Capsicum annuum L.): subcellular rearrangements through development.

    PubMed

    Bárány, Ivett; González-Melendi, Pablo; Fadón, Begoña; Mitykó, Judit; Risueño, María C; Testillano, Pilar S

    2005-09-01

    Background information. In vitro-cultured microspores, after an appropriate stress treatment, can switch towards an embryogenic pathway. This process, known as microspore embryogenesis, is an important tool in plant breeding. Basic studies on this process in economically interesting crops, especially in recalcitrant plants, are very limited and the sequence of events is poorly understood. In situ studies are very convenient for an appropriate dissection of microspore embryogenesis, a process in which a mixture of different cell populations (induced and non-induced) develop asynchronically.Results. In the present study, the occurrence of defined subcellular rearrangements has been investigated during early microspore embryogenesis in pepper, an horticultural crop of agronomic interest, in relation to proliferation and differentiation events. Haploid plants of Capsicum annuum L. (var. Yolo Wonder B) have been regenerated from in vitro anther cultures by a heat treatment at 35 degrees C for 8 days. Morphogenesis of microspore-derived embryos has been analysed, at both light and electron microscopy levels, using low-temperature-processed, well-preserved specimens. The comparison with the normal gametophytic development revealed changes in cell organization after embryogenesis induction, and permitted the characterization of the time sequence of a set of structural events, not previously defined in pepper, related to the activation of proliferative activity and differentiation. These changes mainly affected the plastids, the vacuolar compartment, the cell wall and the nucleus. Further differentiation processes mimicked that of the zygotic development.Conclusions. The reported changes can be considered as markers of the microspore embryogenesis. They have increased the understanding of the mechanisms controlling the switch and progression of the microspore embryogenesis, which could help to improve its efficiency and to direct strategies, especially in agronomically interesting crops. PMID:15910280

  20. Somatic cell genetics

    SciTech Connect

    Davidson, R.L.

    1984-01-01

    This volume traces the major developments of somatic cell genetics via 47 critical papers on somatic cell hybridization, gene transfer, and mutant mammalian cells. Recognized authorities emphasize the importance of applying the combined approach of cell genetics and recombinant DNA to questions of developments, regulations, and growth of both normal and tumor cells.

  1. Isolation and characterization of a diverse set of genes from carrot somatic embryos.

    PubMed Central

    Lin, X; Hwang, G J; Zimmerman, J L

    1996-01-01

    The early events in plant embryogenesis are critical for pattern formation, since it is during this process that the primary apical meristems and the embryo polarity axis are established. However, little is known about the molecular events that are unique to the early stages of embryogenesis. This study of gene expression during plant embryogenesis is focused on identifying molecular markers from carrot (Daucus carota) somatic embryos and characterizing the expression and regulation of these genes through embryo development. A cDNA library, prepared from polysomal mRNA of globular embryos, was screened using a subtracted probe; 49 clones were isolated and preliminarily characterized. Sequence analysis revealed a large set of genes, including many new genes, that are expressed in a variety of patterns during embryogenesis and may be regulated by different molecular mechanisms. To our knowledge, this group of clones represents the largest collection of embryo-enhanced genes isolated thus far, and demonstrates the utility of the subtracted-probe approach to the somatic embryo system. It is anticipated that many of these genes may serve as useful molecular markers for early embryo development. PMID:8938424

  2. Hepatocystin is Essential for TRPM7 Function During Early Embryogenesis

    PubMed Central

    Overton, Jeffrey D.; Komiya, Yuko; Mezzacappa, Courtney; Nama, Kaushik; Cai, Na; Lou, Liping; Fedeles, Sorin V.; Habas, Raymond; Runnels, Loren W.

    2015-01-01

    Mutations in protein kinase C substrate 80K-H (PRKCSH), which encodes for an 80?KDa protein named hepatocystin (80K-H, PRKCSH), gives rise to polycystic liver disease (PCLD). Hepatocystin functions as the noncatalytic beta subunit of Glucosidase II, an endoplasmic reticulum (ER)-resident enzyme involved in processing and quality control of newly synthesized glycoproteins. Patients harboring heterozygous germline mutations in PRKCSH are thought to develop renal cysts as a result of somatic loss of the second allele, which subsequently interferes with expression of the TRP channel polycystin-2 (PKD2). Deletion of both alleles of PRKCSH in mice results in embryonic lethality before embryonic day E11.5. Here, we investigated the function of hepatocystin during Xenopus laevis embryogenesis and identified hepatocystin as a binding partner of the TRPM7 ion channel, whose function is required for vertebrate gastrulation. We find that TRPM7 functions synergistically with hepatocystin. Although other N-glycosylated proteins are critical to early development, overexpression of TRPM7 in Xenopus laevis embryos was sufficient to fully rescue the gastrulation defect caused by loss of hepatocystin. We observed that depletion of hepatocystin in Xenopus laevis embryos decreased TRPM7 expression, indicating that the early embryonic lethality caused by loss of hepatocystin is mainly due to impairment of TRPM7 protein expression. PMID:26671672

  3. Left-Right Asymmetry in Animal Embryogenesis

    E-print Network

    Levin, Michael

    1 Left-Right Asymmetry in Animal Embryogenesis Michael Levin Cell Biology dept. Bldg. C1, rm. 403 of a given type) differences between the left and right sides of an animal's morphology. This specifically of an organism looking the same to some level of detail on either side of a symmetry line). Animal body- plans

  4. Two waves of programmed cell death occur during formation and development of somatic embryos in the gymnosperm, Norway spruce.

    PubMed

    Filonova, L H; Bozhkov, P V; Brukhin, V B; Daniel, G; Zhivotovsky, B; von Arnold, S

    2000-12-01

    In the animal life cycle, the earliest manifestations of programmed cell death (PCD) can already be seen during embryogenesis. The aim of this work was to determine if PCD is also involved in the elimination of certain cells during plant embryogenesis. We used a model system of Norway spruce somatic embryogenesis, which represents a multistep developmental pathway with two broad phases. The first phase is represented by proliferating proembryogenic masses (PEMs). The second phase encompasses development of somatic embryos, which arise from PEMs and proceed through the same sequence of stages as described for their zygotic counterparts. Here we demonstrate two successive waves of PCD, which are implicated in the transition from PEMs to somatic embryos and in correct embryonic pattern formation, respectively. The first wave of PCD is responsible for the degradation of PEMs when they give rise to somatic embryos. We show that PCD in PEM cells and embryo formation are closely interlinked processes, both stimulated upon withdrawal or partial depletion of auxins and cytokinins. The second wave of PCD eliminates terminally differentiated embryo-suspensor cells during early embryogeny. During the dismantling phase of PCD, PEM and embryo-suspensor cells exhibit progressive autolysis, resulting in the formation of a large central vacuole. Autolytic degradation of the cytoplasm is accompanied by lobing and budding-like segmentation of the nucleus. Nuclear DNA undergoes fragmentation into both large fragments of about 50 kb and multiples of approximately 180 bp. The tonoplast rupture is delayed until lysis of the cytoplasm and organelles, including the nucleus, is almost complete. The protoplasm then disappears, leaving a cellular corpse represented by only the cell wall. This pathway of cell dismantling suggests overlapping of apoptotic and autophagic types of PCD during somatic embryogenesis in Norway spruce. PMID:11082033

  5. Shusterman on Somatic Experience

    ERIC Educational Resources Information Center

    Maattanen, Pentti

    2010-01-01

    Richard Shusterman's "Body Consciousness" aims at formulating a theory of somaesthetics and somatic experience. There has indeed been a growing interest in the role of the body in experience. Shusterman examines the arguments of six important writers who have been influential in this discussion. The emphasis on the body is natural for a…

  6. Selection of Norway spruce somatic embryos by computer vision

    NASA Astrophysics Data System (ADS)

    Hamalainen, Jari J.; Jokinen, Kari J.

    1993-05-01

    A computer vision system was developed for the classification of plant somatic embryos. The embryos are in a Petri dish that is transferred with constant speed and they are recognized as they pass a line scan camera. A classification algorithm needs to be installed for every plant species. This paper describes an algorithm for the recognition of Norway spruce (Picea abies) embryos. A short review of conifer micropropagation by somatic embryogenesis is also given. The recognition algorithm is based on features calculated from the boundary of the object. Only part of the boundary corresponding to the developing cotyledons (2 - 15) and the straight sides of the embryo are used for recognition. An index of the length of the cotyledons describes the developmental stage of the embryo. The testing set for classifier performance consisted of 118 embryos and 478 nonembryos. With the classification tolerances chosen 69% of the objects classified as embryos by a human classifier were selected and 31$% rejected. Less than 1% of the nonembryos were classified as embryos. The basic features developed can probably be easily adapted for the recognition of other conifer somatic embryos.

  7. Mitogen-activated protein kinases are developmentally regulated during stress-induced microspore embryogenesis in Brassica napus L.

    PubMed

    Seguí-Simarro, José M; Testillano, Pilar S; Jouannic, Stefan; Henry, Yves; Risueño, Maria C

    2005-06-01

    Plant mitogen-activated protein kinase (MAPK) cascades are involved in extracellular stress signalling pathways, leading to different cellular responses. Stress-induced microspore embryogenesis involves the internalization of an extracellular stress signal, generating a number of cellular responses where MAPK cascades might be involved. These responses include a change of the developmental programme, the entry into an early proliferative stage and, subsequently, into differentiation stages during haploid embryogenesis. In this work we studied the expression during microspore embryogenesis of several kinases, to assess their putative role in these events. The known Brassica napus MAP kinase kinase kinases (MAP3Ks BnMAP3Kalpha1, BnMAP3Kbeta1 and BnMAP3Kepsilon, the BnBSKtheta kinase and B. napus extracellular signal-regulated kinase (ERK) homologues were analysed by electron microscope (EM) in situ hybridization, immuno-gold labelling, immunofluorescence and western blotting. The differential in situ expression of these kinases suggests a role for them during embryogenesis. Two different expression patterns were observed, indicating a different regulation. BnMAP3Kalpha1, BnMAP3Kepsilon, and the ERKs showed a pattern consistent with a role mainly in proliferative events. Conversely, BnMAP3Kbeta1 and BnBSKtheta, presented a pattern that suggested an involvement in differentiation stages. In addition, ERK homologues migrate to the nucleus immediately after induction, being found in a phosphorylated state in a larger amount. PMID:15895239

  8. Genetic Regulatory Networks in Embryogenesis and Evolution

    NASA Technical Reports Server (NTRS)

    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.

  9. Embryogenesis of brassica rapa l. under clinorotation

    NASA Astrophysics Data System (ADS)

    Popova, A.; Ivanenko, G.

    Investigation of reproductive development of higher plants in spaceflight represents scientific interest first of all with the necessity to work out the plant space technologies for creation of controlled life-support systems. In such systems mainly the higher plants are considered to be an important component that makes it necessary to obtain the several generations of higher plants with their full ontogenesis. As a rule, seeds obtained in three species of the higher plants in a series of experiments differ from the control by some parameters (Merkis, Laurinavichius, 1983; Musgrave et al., 1998; 2000; Levinskikh et all. 1999; Stankovich et al., 2002). It was shown, that immature embryos generated in microgravity were at a range of developmental stage, while the ground control embryos had all reached the premature stage of development (Kuang et al., 2003). Besides, the distinctions in a degree of nutrient substances accumulation in them were revealed (Kuang et al., 2000). Therefore, the elucidation of the possible reasons for distortion of plant reproduction in microgravity demands the further research. In this study we examined embryogenesis of higher plant Brassica rapa L. with an application of slow horizontal clinostats, that allows to deprive the plants the opportunity to perceive the gravitational stimulus. Some plants were clinorotated from the moment sowing of seeds; in other series the experiment plants were placed on clinostats after formation of flower buds. Temporal fixation of the material was used in these experiments, which allow to obtain material for studying of consecutive stages of embryogenesis. The development of 2-21 day-old embryos was studied. Comparative embryological analysis has shown a similarity in the main of process of embryo differentiation produced under clinorotation and in the stationary control. At the early stages of embryogenesis, the distortion in suspensor formation was observed more frequently. Embryos generated in clinorotation variant had a wider range of developmental stages in comparison with the stationary control. At the stage of embryo maturation the various deviations in embryo differentiation were revealed. These distortions were connected both with cotyledon and radicle development. Possible reasons for deviations in the process of embryogenesis in condition of altered gravity are discussed.

  10. Somatic embryogenesis of carrot in hormone-free medium: external pH control over morphogenesis

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1990-01-01

    Cultures of preglobular stage proembryos (PGSPs) were initiated from mechanically wounded mature zygotic embryos of carrot, Daucus carota, on a hormone-free, semisolid medium. These PGSPs have been maintained and multiplied for extended periods without their progression into later embryo stages on the same hormone-free medium containing 1 mM NH4+ as the sole nitrogen source. Sustained maintenance of cultures comprised exclusively of PGSPs was dependent on medium pH throughout the culture period. Best growth and multiplication of PGSP cultures occurred when the pH of unbuffered, hormone-free medium fell from 4.5 to 4 over a 2-week period or when buffered medium was titrated to pH 4. If the hormone-free medium was buffered to sustain a pH at or above 4.5, PGSPs developed into later embryo stages. Maintenance with continuous multiplication of PGSPs occurred equally well on medium containing NH4+ or NH4+ and NO3-, but growth was poor with NO3- alone. Additional observations on the effects of medium components such as various nitrogen sources and levels, sucrose concentration, semisolid supports, type of buffer, borate concentration, activated charcoal, and initial pH that permit optimum maintenance of the PGSPs or foster their continued developmental progression into mature embryos and plantlets are reported. The influence of the pH of the hormone-free medium as a determinant in maintaining cultures as PGSPs or allowing their continued embryonic development are unequivocally demonstrated by gross morphology, scanning electron microscopy, and histological preparations.

  11. Effect of weightlessness conditions on the somatic embryogenesis in the culture of carrot cells

    NASA Technical Reports Server (NTRS)

    Butenko, R. G.; Dmitriyeva, N. N.; Ongko, V.; Basyrova, L. V.

    1977-01-01

    A carrot cell culture seeded in Petri dishes in the United States and transported to the USSR was subjected to weightlessness for 20 days during the flight of Kosmos 782. The controls were cultures placed on a centrifuge (1 g) inside the satellite and cultures left on ground in the U.S.S.R. and the United States. A count of structures in the dishes after the flight showed that the number of developing embryonic structures and the extent of their differentiation in weightlessness did not reliably differ from the number and extent of differentiation in structures developed on the ground. Structures with long roots developed in weightlessness. Analysis of the root zones showed that these roots differed by the increased size of the zone of differentiated cells. The increased size of the zones of differentiated cells can indicate earlier development of embryonic structures.

  12. Mutual inductance Mutual induction

    E-print Network

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    Mutual inductance Mutual induction ­ current in one coil induces emf in other coil Distinguish from = #12;Mutual inductance Rearrange equation Vary i1 with time Faraday's law Induced emf in coil 2 due = dt d N 21 2 -=2 dt di M 1 21-=2 #12;Mutual inductance Reverse roles of coils What is induced emf

  13. Control of Wild Carrot Somatic Embryo Development by Antioxidants 1

    PubMed Central

    Earnshaw, Brent A.; Johnson, Morris A.

    1987-01-01

    As we previously reported for glutathione (GSH), both ascorbic acid (AA) and vitamin E were observed to suppress wild carrot (Daucus carota L.) somatic embryogenesis with little concomitant effect on biomass. Endogenous concentrations of AA were lower during embryo development than during cell proliferation, exhibiting a temporal pattern nearly identical to that of GSH. GSSG (oxidized GSH) reductase was found to be considerably more active in proliferating than in developing cultures, whereas no difference was evident in the case of dehydroascorbate (DHA) reductase. Both GSH and AA concentrations in these cells are governed by 2,4-D. These results show that redox status is a strong determinant of proliferative versus developmental growth and indicate that the mode of action of 2,4-D in this system may be explained at least in part by its influence on endogenous antioxidant levels. PMID:16665669

  14. Rhizobium Lipooligosaccharides Rescue a Carrot Somatic Embryo Mutant.

    PubMed Central

    De Jong, AJ; Heidstra, R; Spaink, HP; Hartog, MV; Meijer, EA; Hendriks, T; Schiavo, FL; Terzi, M; Bisseling, T; Van Kammen, A; De Vries, SC

    1993-01-01

    At a nonpermissive temperature, somatic embryos of the temperature-sensitive (ts) carrot cell mutant ts11 only proceed beyond the globular embryo stage in the presence of medium conditioned by wild-type embryos. The causative component in the conditioned medium has previously been identified as a 32-kD acidic endochitinase. In search of a function for this enzyme in plant embryogenesis, several compounds that contain oligomers of N-acetylglucosamine were tested for their ability to promote ts11 embryo formation. Of these compounds, only the Rhizobium lipooligosaccharides or nodulation (Nod) factors were found to be effective in rescuing the formation of ts11 embryos. These results suggest that N-acetylglucosamine-containing lipooligosaccharides from bacterial origin can mimic the effect of the carrot endochitinase. This endochitinase may therefore be involved in the generation of plant analogs of the Rhizobium Nod factors. PMID:12271077

  15. Comparative proteomic analysis of somatic embryo maturation in Carica papaya L.

    PubMed Central

    2014-01-01

    Background Somatic embryogenesis is a complex process regulated by numerous factors. The identification of proteins that are differentially expressed during plant development could result in the development of molecular markers of plant metabolism and provide information contributing to the monitoring and understanding of different biological responses. In addition, the identification of molecular markers could lead to the optimization of protocols allowing the use of biotechnology for papaya propagation and reproduction. This work aimed to investigate the effects of polyethylene glycol (PEG) on somatic embryo development and the protein expression profile during somatic embryo maturation in papaya (Carica papaya L.). Results The maturation treatment supplemented with 6% PEG (PEG6) resulted in the greatest number of somatic embryos and induced differential protein expression compared with cultures grown under the control treatment. Among 135 spots selected for MS/MS analysis, 76 spots were successfully identified, 38 of which were common to both treatments, while 14 spots were unique to the control treatment, and 24 spots were unique to the PEG6 treatment. The identified proteins were assigned to seven categories or were unclassified. The most representative class of proteins observed in the control treatment was associated with the stress response (25.8%), while those under PEG6 treatment were carbohydrate and energy metabolism (18.4%) and the stress response (18.4%). Conclusions The differential expression of three proteins (enolase, esterase and ADH3) induced by PEG6 treatment could play an important role in maturation, and these proteins could be characterized as candidate biomarkers of somatic embryogenesis in papaya. PMID:25076862

  16. 5-azacytidine promotes microspore embryogenesis initiation by decreasing global DNA methylation, but prevents subsequent embryo development in rapeseed and barley

    PubMed Central

    Solís, María-Teresa; El-Tantawy, Ahmed-Abdalla; Cano, Vanesa; Risueño, María C.; Testillano, Pilar S.

    2015-01-01

    Microspores are reprogrammed by stress in vitro toward embryogenesis. This process is an important tool in breeding to obtain double-haploid plants. DNA methylation is a major epigenetic modification that changes in differentiation and proliferation. We have shown changes in global DNA methylation during microspore reprogramming. 5-Azacytidine (AzaC) cannot be methylated and leads to DNA hypomethylation. AzaC is a useful demethylating agent to study DNA dynamics, with a potential application in microspore embryogenesis. This work analyzes the effects of short and long AzaC treatments on microspore embryogenesis initiation and progression in two species, the dicot Brassica napus and the monocot Hordeum vulgare. This involved the quantitative analyses of proembryo and embryo production, the quantification of DNA methylation, 5-methyl-deoxy-cytidine (5mdC) immunofluorescence and confocal microscopy, and the analysis of chromatin organization (condensation/decondensation) by light and electron microscopy. Four days of AzaC treatments (2.5 ?M) increased embryo induction, response associated with a decrease of DNA methylation, modified 5mdC, and heterochromatin patterns compared to untreated embryos. By contrast, longer AzaC treatments diminished embryo production. Similar effects were found in both species, indicating that DNA demethylation promotes microspore reprogramming, totipotency acquisition, and embryogenesis initiation, while embryo differentiation requires de novo DNA methylation and is prevented by AzaC. This suggests a role for DNA methylation in the repression of microspore reprogramming and possibly totipotency acquisition. Results provide new insights into the role of epigenetic modifications in microspore embryogenesis and suggest a potential benefit of inhibitors, such as AzaC, to improve the process efficiency in biotechnology and breeding programs. PMID:26161085

  17. 5-azacytidine promotes microspore embryogenesis initiation by decreasing global DNA methylation, but prevents subsequent embryo development in rapeseed and barley.

    PubMed

    Solís, María-Teresa; El-Tantawy, Ahmed-Abdalla; Cano, Vanesa; Risueño, María C; Testillano, Pilar S

    2015-01-01

    Microspores are reprogrammed by stress in vitro toward embryogenesis. This process is an important tool in breeding to obtain double-haploid plants. DNA methylation is a major epigenetic modification that changes in differentiation and proliferation. We have shown changes in global DNA methylation during microspore reprogramming. 5-Azacytidine (AzaC) cannot be methylated and leads to DNA hypomethylation. AzaC is a useful demethylating agent to study DNA dynamics, with a potential application in microspore embryogenesis. This work analyzes the effects of short and long AzaC treatments on microspore embryogenesis initiation and progression in two species, the dicot Brassica napus and the monocot Hordeum vulgare. This involved the quantitative analyses of proembryo and embryo production, the quantification of DNA methylation, 5-methyl-deoxy-cytidine (5mdC) immunofluorescence and confocal microscopy, and the analysis of chromatin organization (condensation/decondensation) by light and electron microscopy. Four days of AzaC treatments (2.5 ?M) increased embryo induction, response associated with a decrease of DNA methylation, modified 5mdC, and heterochromatin patterns compared to untreated embryos. By contrast, longer AzaC treatments diminished embryo production. Similar effects were found in both species, indicating that DNA demethylation promotes microspore reprogramming, totipotency acquisition, and embryogenesis initiation, while embryo differentiation requires de novo DNA methylation and is prevented by AzaC. This suggests a role for DNA methylation in the repression of microspore reprogramming and possibly totipotency acquisition. Results provide new insights into the role of epigenetic modifications in microspore embryogenesis and suggest a potential benefit of inhibitors, such as AzaC, to improve the process efficiency in biotechnology and breeding programs. PMID:26161085

  18. Direct somatic lineage conversion.

    PubMed

    Tanabe, Koji; Haag, Daniel; Wernig, Marius

    2015-10-19

    The predominant view of embryonic development and cell differentiation has been that rigid and even irreversible epigenetic marks are laid down along the path of cell specialization ensuring the proper silencing of unrelated lineage programmes. This model made the prediction that specialized cell types are stable and cannot be redirected into other lineages. Accordingly, early attempts to change the identity of somatic cells had little success and was limited to conversions between closely related cell types. Nuclear transplantation experiments demonstrated, however, that specialized cells even from adult mammals can be reprogrammed into a totipotent state. The discovery that a small combination of transcription factors can reprogramme cells to pluripotency without the need of oocytes further supported the view that these epigenetic barriers can be overcome much easier than assumed, but the extent of this flexibility was still unclear. When we showed that a differentiated mesodermal cell can be directly converted to a differentiated ectodermal cell without a pluripotent intermediate, it was suggested that in principle any cell type could be converted into any other cell type. Indeed, the work of several groups in recent years has provided many more examples of direct somatic lineage conversions. Today, the question is not anymore whether a specific cell type can be generated by direct reprogramming but how it can be induced. PMID:26416679

  19. High genetic and epigenetic stability in Coffea arabica plants derived from embryogenic suspensions and secondary embryogenesis as revealed by AFLP, MSAP and the phenotypic variation rate.

    PubMed

    Bobadilla Landey, Roberto; Cenci, Alberto; Georget, Frédéric; Bertrand, Benoît; Camayo, Gloria; Dechamp, Eveline; Herrera, Juan Carlos; Santoni, Sylvain; Lashermes, Philippe; Simpson, June; Etienne, Hervé

    2013-01-01

    Embryogenic suspensions that involve extensive cell division are risky in respect to genome and epigenome instability. Elevated frequencies of somaclonal variation in embryogenic suspension-derived plants were reported in many species, including coffee. This problem could be overcome by using culture conditions that allow moderate cell proliferation. In view of true-to-type large-scale propagation of C. arabica hybrids, suspension protocols based on low 2,4-D concentrations and short proliferation periods were developed. As mechanisms leading to somaclonal variation are often complex, the phenotypic, genetic and epigenetic changes were jointly assessed so as to accurately evaluate the conformity of suspension-derived plants. The effects of embryogenic suspensions and secondary embryogenesis, used as proliferation systems, on the genetic conformity of somatic embryogenesis-derived plants (emblings) were assessed in two hybrids. When applied over a 6 month period, both systems ensured very low somaclonal variation rates, as observed through massive phenotypic observations in field plots (0.74% from 200,000 plant). Molecular AFLP and MSAP analyses performed on 145 three year-old emblings showed that polymorphism between mother plants and emblings was extremely low, i.e. ranges of 0-0.003% and 0.07-0.18% respectively, with no significant difference between the proliferation systems for the two hybrids. No embling was found to cumulate more than three methylation polymorphisms. No relation was established between the variant phenotype (27 variants studied) and a particular MSAP pattern. Chromosome counting showed that 7 of the 11 variant emblings analyzed were characterized by the loss of 1-3 chromosomes. This work showed that both embryogenic suspensions and secondary embryogenesis are reliable for true-to-type propagation of elite material. Molecular analyses revealed that genetic and epigenetic alterations are particularly limited during coffee somatic embryogenesis. The main change in most of the rare phenotypic variants was aneuploidy, indicating that mitotic aberrations play a major role in somaclonal variation in coffee. PMID:23418563

  20. Oil body biogenesis during Brassica napus embryogenesis.

    PubMed

    He, Yu-Qing; Wu, Yan

    2009-08-01

    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 turn 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. PMID:19686376

  1. The freshwater planarian Schmidtea mediterranea: embryogenesis, stem cells and regeneration

    E-print Network

    Alvarado, Alejandro Sánchez

    The freshwater planarian Schmidtea mediterranea: embryogenesis, stem cells and regeneration Commentary Alejandro Sa´ nchez Alvarado Planarians have been used as a model to study development and pharmacological manipulations. Recently, the dissection of planarians has become more molecular in nature

  2. Detection of Epigenetic Modifications During Microspore Embryogenesis: Analysis of DNA Methylation Patterns Dynamics.

    PubMed

    Testillano, Pilar S; Risueño, María Carmen

    2016-01-01

    Methylation of 5-deoxy-cytidines of DNA constitutes a prominent epigenetic modification of the chromatin fiber which is locked in a transcriptionally inactive conformation. Changes in global DNA methylation are involved in many plant developmental processes during proliferation and differentiation events. The analysis of the changes of global DNA methylation distribution patterns during microspore embryogenesis induction and progression will inform on the regulatory mechanisms of the process, helping in the design of protocols to improve its efficiency in different species. To investigate the DNA methylation dynamics during microspore embryogenesis in the different cell types present in the cultures, the analysis of spatial and temporal pattern of nuclear distribution of 5-methyl-deoxy-cytidine (5mdC) constitutes a potent approach. The immunolocalization of 5mdC on sections and subsequent confocal laser microscopy analysis have been developed for in situ cellular analysis of a variety of plant samples, including embryogenic microspore and anther cultures. Quantification of 5mdC immunofluorescence intensity by image analysis software also permits to estimate differences in global DNA methylation levels among different cell types during development. PMID:26619883

  3. Metabolome Analysis of Drosophila melanogaster during Embryogenesis

    PubMed Central

    An, Phan Nguyen Thuy; Yamaguchi, Masamitsu; Bamba, Takeshi; Fukusaki, Eiichiro

    2014-01-01

    The Drosophila melanogaster embryo has been widely utilized as a model for genetics and developmental biology due to its small size, short generation time, and large brood size. Information on embryonic metabolism during developmental progression is important for further understanding the mechanisms of Drosophila embryogenesis. Therefore, the aim of this study is to assess the changes in embryos’ metabolome that occur at different stages of the Drosophila embryonic development. Time course samples of Drosophila embryos were subjected to GC/MS-based metabolome analysis for profiling of low molecular weight hydrophilic metabolites, including sugars, amino acids, and organic acids. The results showed that the metabolic profiles of Drosophila embryo varied during the course of development and there was a strong correlation between the metabolome and different embryonic stages. Using the metabolome information, we were able to establish a prediction model for developmental stages of embryos starting from their high-resolution quantitative metabolite composition. Among the important metabolites revealed from our model, we suggest that different amino acids appear to play distinct roles in different developmental stages and an appropriate balance in trehalose-glucose ratio is crucial to supply the carbohydrate source for the development of Drosophila embryo. PMID:25121768

  4. Characterization of conservative somatic instability of the CAG repeat region in Huntington`s disease

    SciTech Connect

    Schaefer, F.V.; Calikoglu, A.S.; Whetsell, L.H.

    1994-09-01

    Instability and enlargement of a CAG repeat region at the beginning of the huntingtin gene (IT-15) has been linked with Huntington`s disease. The CAG repeat size shows a highly significant correlation with age-of-onset of clinicial features in individuals with 40 or more repeats who have Huntington disease. The clinical status of nonsymptomatic individuals with 30 to 39 CAG repeats is considered ambiguous. In order to define more carefully the nature of the HD expansion instability, we examined patients in our HD population using a discriminating fluorescence-based PCR approach. The degree of somatic mutation increases with both earlier age of onset and the size of the inherited allele. A single prominent band one repeat larger than the index peak was typical in individuals with 40-41 CAG repeats. Three to four larger bands are typically discerned in individuals with 50 or more repeats. In an extreme example, an individual with approximately 95 repeats had at least 8 prominent bands. Plotting the degree of somatic mutation relative to the size of the HD allele shows somatic mutation activity increases with size. By this approach 40-60% of the alleles in a 40-41 CAG repeat HD loci is represented in the primary allele. In contrast, the primary allele represents a relatively minor proportion of the total alleles for expansions greater than 50 CAG repeats (10-20%). The limited range of somatic mutation suggest that the instability is restricted to very early stages of embryogenesis before tissue development diverges or that persistent somatic instability occurs at a slow rate. Therefore, the properties of somatic instability in Huntington`s disease have aspects that are both in common but also different from that found in other trinucleotide repeat expanding diseases such as myotonic muscular dystrophy and fragile X syndrome.

  5. Pollen embryogenesis to induce, detect, and analyze mutants

    SciTech Connect

    Constantin, M.J.

    1981-01-01

    The development of fully differentiated plants from individual pollen grains through a series of developmental phases that resemble embryogenesis beginning with the zygote was demonstrated during the mid-1960's. This technology opened the door to the use of haploid plants (sporophytes with the gametic number of chromosomes) for plant breeding and genetic studies, biochemical and metabolic studies, and the selection of mutations. Although pollen embryogenesis has been demonstrated successfully in numerous plant genera, the procedure cannot as yet be used routinely to generate large populations of plants for experiments. Practical results from use of the technology in genetic toxicology research to detect mutations have failed to fully realize the theoretical potential; further developments of the technology could overcome the limitations. Pollen embryogenesis could be used to develop plants from mutant pollen grains to verify that genetic changes are involved. Through either spontaneous or induced chromosome doubling, these plants can be made homozygous and used to analyze genetically the mutants involved. The success of this approach will depend on the mutant frequency relative to the fraction of pollen grains that undergo embryogenesis; these two factors will dictate population size needed for success. Research effort is needed to further develop pollen embryogenesis for use in the detection of genotoxins under both laboratory and in situ conditions.

  6. Are Early Somatic Embryos of the Norway Spruce (Picea abies (L.) Karst.) Organised?

    PubMed Central

    Petrek, Jiri; Zitka, Ondrej; Adam, Vojtech; Bartusek, Karel; Anjum, Naser A.; Pereira, Eduarda; Havel, Ladislav; Kizek, Rene

    2015-01-01

    Background Somatic embryogenesis in conifer species has great potential for the forestry industry. Hence, a number of methods have been developed for their efficient and rapid propagation through somatic embryogenesis. Although information is available regarding the previous process-mediated generation of embryogenic cells to form somatic embryos, there is a dearth of information in the literature on the detailed structure of these clusters. Methodology/Principal Findings The main aim of this study was to provide a more detailed structure of the embryogenic tissue clusters obtained through the in vitro propagation of the Norway spruce (Picea abies (L.) Karst.). We primarily focused on the growth of early somatic embryos (ESEs). The data on ESE growth suggested that there may be clear distinctions between their inner and outer regions. Therefore, we selected ESEs collected on the 56th day after sub-cultivation to dissect the homogeneity of the ESE clusters. Two colourimetric assays (acetocarmine and fluorescein diacetate/propidium iodide staining) and one metabolic assay based on the use of 2,3,5-triphenyltetrazolium chloride uncovered large differences in the metabolic activity inside the cluster. Next, we performed nuclear magnetic resonance measurements. The ESE cluster seemed to be compactly aggregated during the first four weeks of cultivation; thereafter, the difference between the 1H nuclei concentration in the inner and outer clusters was more evident. There were clear differences in the visual appearance of embryos from the outer and inner regions. Finally, a cluster was divided into six parts (three each from the inner and the outer regions of the embryo) to determine their growth and viability. The innermost embryos (centripetally towards the cluster centre) could grow after sub-cultivation but exhibited the slowest rate and required the longest time to reach the common growth rate. To confirm our hypothesis on the organisation of the ESE cluster, we investigated the effect of cluster orientation on the cultivation medium and the influence of the change of the cluster’s three-dimensional orientation on its development. Maintaining the same position when transferring ESEs into new cultivation medium seemed to be necessary because changes in the orientation significantly affected ESE growth. Conclusions and Significance This work illustrated the possible inner organisation of ESEs. The outer layer of ESEs is formed by individual somatic embryos with high metabolic activity (and with high demands for nutrients, oxygen and water), while an embryonal group is directed outside of the ESE cluster. Somatic embryos with depressed metabolic activity were localised in the inner regions, where these embryonic tissues probably have a very important transport function. PMID:26624287

  7. Globin gene expression in somatic cell hybrids.

    PubMed

    Anderson, W F; Chiang, Y L; Sanders-Haigh, L; Ley, T J

    1983-01-01

    Fusions between somatic cell lines have previously yielded evidence for the existence of trans-acting gene regulatory factors. For this reason, we developed a cell line containing a "locked in" human 11-X translocation chromosome (containing the beta-globin-like gene cluster) in MEL cells. The human 11-X chromosome is stably integrated in the "M11-X" cell line, and single-copy human gamma and beta genes are present. After induction with HMBA, M11-X cells produced 500 copies per cell of correctly initiated, processed, and terminated human beta-globin mRNA; authentic human beta-globin chains were also produced at a low level. Despite the presence of normally arranged human gamma-globin genes, no gamma-globin mRNA could be detected after HMBA induction. However, cytosine residues near the gamma-globin gene promoters are completely methylated in these cells, suggesting that the gamma-globin genes may be repressed in part by DNA methylation. The pattern of human globin gene expression in M11-X cells may be affected by methylation and/or by trans-acting factors produced by these tetraploid cells. PMID:6320217

  8. Psychopharmacotherapy of somatic symptoms disorders.

    PubMed

    Somashekar, Bettahalasoor; Jainer, Ashok; Wuntakal, Balaji

    2013-02-01

    Somatic symptoms are often common causes for medical consultation. The treatment of somatic symptoms disorders is complicated by lack of boundary, conceptual clarity, and overemphasis on psychosocial causation and effectiveness of psychological treatments. In clinical practice all classes of psychotropics are used to treat somatic symptoms disorder. Five principal groups of drugs such as tricyclic antidepressants (TCA), serotonin reuptake inhibitors (SSRI), serotonin and noradrenalin reuptake inhibitors (SNRI), atypical antipsychotics and herbal medication are systematically studied. The evidence indicates that all five groups are effective in a wide range of disorders. All classes of antidepressants seem to be effective against somatoform and related disorders. SSRIs are more effective against hypochondriasis and body dysmorphic disorder (BDD), and SNRIs appear to be more effective than other antidepressants when pain is the predominant symptom. Research leaves many unanswered questions regarding dosing, duration of treatment, sustainability of improvement in the long term and differential response to different class drugs. Further studies need to focus on treatments based on clinical features/psychopathology and collaborative research with other specialists in understanding the relation of somatic symptom disorders and functional somatic syndromes (FSS), and comparing psychotropics and non-psychotropics and combinations treatments. PMID:23383672

  9. Muscle formation during embryogenesis of the polychaete Ophryotrocha diadema (Dorvilleidae) – new insights into annelid muscle patterns

    PubMed Central

    Bergter, Annette; Brubacher, John L; Paululat, Achim

    2008-01-01

    Background The standard textbook information that annelid musculature consists of oligochaete-like outer circular and inner longitudinal muscle-layers has recently been called into question by observations of a variety of complex muscle systems in numerous polychaete taxa. To clarify the ancestral muscle arrangement in this taxon, we compared myogenetic patterns during embryogenesis of Ophryotrocha diadema with available data on oligochaete and polychaete myogenesis. This work addresses the conflicting views on the ground pattern of annelids, and adds to our knowledge of the evolution of lophotrochozoan taxa. Results Somatic musculature in Ophryotrocha diadema can be classified into the trunk, prostomial/peristomial, and parapodial muscle complexes. The trunk muscles comprise strong bilateral pairs of distinct dorsal and ventral longitudinal strands. The latter are the first to differentiate during myogenesis. They originate within the peristomium and grow posteriorly through the continuous addition of myocytes. Later, the longitudinal muscles also expand anteriorly and form a complex arrangement of prostomial muscles. Four embryonic parapodia differentiate in an anterior-to-posterior progression, significantly contributing to the somatic musculature. Several diagonal and transverse muscles are present dorsally. Some of the latter are situated external to the longitudinal muscles, which implies they are homologous to the circular muscles of oligochaetes. These circular fibers are only weakly developed, and do not appear to form complete muscle circles. Conclusion Comparison of embryonic muscle patterns showed distinct similarities between myogenetic processes in Ophryotrocha diadema and those of oligochaete species, which allows us to relate the diverse adult muscle arrangements of these annelid taxa to each other. These findings provide significant clues for the interpretation of evolutionary changes in annelid musculature. PMID:18171469

  10. Genotoxic effects of cisplatin in somatic tissue of Drosophila melanogaster

    SciTech Connect

    Katz, A.J.

    1987-01-01

    Third instar larvae of Drosophila melanogaster transdihybrid for mwh and flr were exposed to varying concentrations of cisplatin by feeding on dry media wetted with aqueous solutions of the test compound. Larval feeding continued until pupation, and surviving transdihybrid adults were collected seven days following commencement of feeding. Wings of adults were removed and scored under 400X magnification for the presence of twin spots and single spots comprised of clones of cells possessing malformed wing hairs. Cisplatin was found to induce both twin spots and single spots, and significant linear concentration-response relationships were obtained with respect to the induction of all endpoints. This capacity to induce mitotic exchange in the somatic tissue of Drosophila compares well with the compound's reported ability to induce chromosome breaks in Drosophila germ cells. However, not all compounds possess similar genotoxic profiles in the somatic an germ tissue of Drosophila.

  11. GENOMIC ANALYSIS OF CANCER TISSUE REVEALS THAT SOMATIC MUTATIONS COMMONLY OCCUR IN A SPECIFIC MOTIF

    PubMed Central

    Makridakis, Nick M; Ferraz, Lúcio Fábio Caldas; Reichardt, Juergen KV

    2009-01-01

    Somatic mutations are hallmarks of cancer progression. We sequenced 26 matched human prostate tumor and constitutional DNA samples for somatic alterations in the SRD5A2, HPRT, and HSD3B2 genes, and identified 71 nucleotide substitutions. 79% (56/71) of these substitutions occur within a WKVnRRRnVWK sequence (THEMIS motif; W= A/T, K= G/T, V= G/A/C, R= purine (A/G) and n= any nucleotide), with one mismatch allowed. Literature searches identified this motif with one mismatch allowed in 66% (37/ 56) of the somatic prostate cancer mutations and in 74% (90/ 122) of the somatic breast cancer mutations found in all human genes analyzed. We also found the THEMIS motif with one allowed mismatch in 88% (23/26) of the ras1 gene somatic mutations formed in the SENCAR (SENsitive to skin CARcinogenesis) mouse model, after induction of error-prone DNA repair following mutagenic treatment. The high prevalence of the motif in each of the above mentioned cases cannot be explained by chance (p < 0.046). We further identified 27 somatic mutations in the error-prone DNA polymerase genes pol ?, pol ? and pol ? in these prostate cancer patients. The data suggest that most somatic nucleotide substitutions in human cancer may occur in sites that conform to the THEMIS motif. These mutations may be caused by “mutator” mutations in error-prone DNA polymerase genes. PMID:18623241

  12. Axes, planes and tubes, or the geometry of embryogenesis.

    PubMed

    Brauckmann, Sabine

    2011-12-01

    The paper presents selected figures of chick embryogenesis as depicted in the classic studies of Caspar Friedrich Wolff (1734-1794), Christian Heinrich Pander (1794-1865) and Karl Ernst von Baer (1792-1786). My main objective here is (1) to demonstrate how the imagery of Wolff, Pander and Baer attempted to project an image of a 3-dimensional rotating body into static figures on paper by means of linear contours, and (2) to ponder on the efficacy and pervasiveness of dots, lines and arrows for depicting embryogenesis. PMID:22035710

  13. A model system for analyzing somatic

    E-print Network

    Cai, Long

    and, possibly, aging1. Somatic muta- genesis is difficult to study in higher organisms, with mostA model system for analyzing somatic mutations in Drosophila melanogaster Ana Maria Garcia1 model for studying a broad range of somatic mutations by inserting a lacZ plasmid reporter construct (p

  14. Detection of somatic mosaicism in DMD using computer-assisted laser densitometry

    SciTech Connect

    Sutherland, J.E.; Allingham-Hawkins, D.J.; MacKenzie, J.

    1994-09-01

    Approximately two-thirds of Duchenne muscular dystrophy (DMD) patients have a deletion in the dystrophin gene located at Xp21.1. Two PCR-based multiplex systems have been developed which detect 98% of deletions in affected males. Diagnosis of carrier females requires densitometry of PCR products following gel electrophoresis to calculate dosage of specific exons. We have developed a system in which fluorescently labelled PCR products are analysed using a GENESCANNER automated fragment analyser (ABI). Dosage is determined using computer-assisted laser densitometry (CALD). Recently, we diagnosed somatic mosaicism in the mother of an affected boy using this method. PCR analysis showed that the patient had a deletion that included exons 47-51 of his dystrophin gene. CALD analysis on the patient`s 36-year-old mother revealed a 29-34% reduction in the intensity of the bands corresponding to the deleted region of the gene rather than the 50% reduction normally seen in carrier females. A skin biopsy was obtain and monoclonal fibroblast colonies were tested by CALD for the deletion. Four of the twenty colonies screened were found to be deleted while the remaining colonies had two intact copies of the gene. We conclude that this patient is a somatic mosaic for DMD and that the mutation was the result of a post-zygotic event. This is the only case of somatic mosaicism detected among 800 women from 400 DMD families tested using CALD in our laboratory. At least one other case of possible somatic mosaicism has been reported but not confirmed. Germinal mosaicism is thought to occur in approximately 10% of mothers of sporadic DMD patients. Our findings indicate that somatic mosaicism is a much rarer condition among DMD carriers, thus suggesting that mitotic mutations in the dystrophin gene are more likely to occur later in embryogenesis after differentiation of the germline.

  15. Spatio-temporal accumulation and activity of calcium-dependent protein kinases during embryogenesis, seed development, and germination in sandalwood.

    PubMed

    Anil, V S; Harmon, A C; Rao, K S

    2000-04-01

    Western-blot analysis and protein kinase assays identified two Ca(2+)-dependent protein kinases (CDPKs) of 55 to 60 kD in soluble protein extracts of embryogenic cultures of sandalwood (Santalum album L.). However, these sandalwood CDPKs (swCDPKs) were absent in plantlets regenerated from somatic embryos. swCDPKs exhibited differential expression (monitored at the level of the protein) and activity in different developmental stages. Zygotic embryos, seedlings, and endosperm showed high accumulation of swCDPK, but the enzyme was not detected in the soluble proteins of shoots and flowers. swCDPK exhibited a temporal pattern of expression in endosperm, showing high accumulation and activity in mature fruit and germinating stages; the enzyme was localized strongly in the storage bodies of the endosperm cells. The study also reports for the first time to our knowledge a post-translational inhibition/inactivation of swCDPK in zygotic embryos during seed dormancy and early stages of germination. The temporal expression of swCDPK during somatic/zygotic embryogenesis, seed maturation, and germination suggests involvement of the enzyme in these developmental processes. PMID:10759499

  16. Bovine somatic cell nuclear transfer.

    PubMed

    Ross, Pablo J; Cibelli, Jose B

    2010-01-01

    Somatic cell nuclear transfer (SCNT) is a technique by which the nucleus of a differentiated cell is introduced into an oocyte from which its genetic material has been removed by a process called enucleation. In mammals, the reconstructed embryo is artificially induced to initiate embryonic development (activation). The oocyte turns the somatic cell nucleus into an embryonic nucleus. This process is called nuclear reprogramming and involves an important change of cell fate, by which the somatic cell nucleus becomes capable of generating all the cell types required for the formation of a new individual, including extraembryonic tissues. Therefore, after transfer of a cloned embryo to a surrogate mother, an offspring genetically identical to the animal from which the somatic cells where isolated, is born. Cloning by nuclear transfer has potential applications in agriculture and biomedicine, but is limited by low efficiency. Cattle were the second mammalian species to be cloned after Dolly the sheep, and it is probably the most widely used species for SCNT experiments. This is, in part due to the high availability of bovine oocytes and the relatively higher efficiency levels usually obtained in cattle. Given the wide utilization of this species for cloning, several alternatives to this basic protocol can be found in the literature. Here we describe a basic protocol for bovine SCNT currently being used in our laboratory, which is amenable for the use of the nuclear transplantation technique for research or commercial purposes. PMID:20336522

  17. [Functional somatization: a conceptual review].

    PubMed

    Fabião, Cristina; Fleming, Manuela; Barbosa, António

    2011-01-01

    The authors have brought together and analised texts about the history of the concept of hysteria. In these texts hysteria is fundamentally considered a disease of organic origin (of the womb), and, in the Middle Age, evidence of demonic possession. From the XVII century onwards, apart from the etiopathogenic concepts, also taken into consideration are aspects connected to the differential diagnosis with other similar entities and the therapy used each period. Even, in subsequent centuries, authors such as Syndenham, who consider hysteria to be a multidimensional entity, are rare. Empiricism has contributed to discoveries in biology and physiology, both general and of the nervous system itself, and given birth to the formulation of the Spinal Irritation Theory and Reflex Theory. These theories have led to strictly organic treatment of hysteria, in the same way that hysterectomies were performed to alleviate somatic symptoms connected to this disease. The introduction of hypnosis in medical practice, with Charcot in X1X century, allowed for the element of suggestion to be observed ( a non organic element) which accompanies the symptoms of hysteria. Two of his disciples, Janet and Freud, would define and isolate psychic mechanisms in the symptoms of hysteria: Dissociation of the consciousness (Janet) and Conversion (Freud). The last one developed a therapeutic method of a psychological nature for hysteria. The therapeutic implications and the pertinence of the distinction between unspecific somatization or functional (of somatic origin) somatization and somatization linked to disassociation mechanisms and conversion (psychic origin) are discussed as well as the evolution of international classification systems of somatization and the questions posed by the algorithms chosen for the cataloguing of symptoms. A revision of the relevant empirical studies about the association of somatization with depressive and anxiety disorders, within the general population, is made. The characteristics that permeate the clinical descriptions of somatoform disorders (whose validity criteria remain weak) and are not integrated within the diagnostic criteria for somatoform disorders are considered. We draw conclusions about the difficulties and consequences of the changes that some authors advocate in relation to the new classification system for somatoform syndromes. PMID:22525627

  18. Introduction Building tissues and organs during embryogenesis involves a

    E-print Network

    Parkhurst, Susan

    (reviewed by Grinnell, 1992; Martin, 1997; Werner and Grose, 2003). The deeper connective tissue is replaced of collagen within the healed connective tissue. Tissue repair in the mouse embryo involves largely the same3021 Introduction Building tissues and organs during embryogenesis involves a series of exquisite

  19. Somatic Mutation, Genomic Variation, and Neurological Disease

    PubMed Central

    Poduri, Annapurna; Evrony, Gilad D.; Cai, Xuyu; Walsh, Christopher A.

    2014-01-01

    Genetic mutations causing human disease are conventionally thought to be inherited through the germ line from one’s parents and present in all somatic (body) cells, except for most cancer mutations, which arise somatically. Increasingly, somatic mutations are being identified in diseases other than cancer, including neurodevelopmental diseases. Somatic mutations can arise during the course of prenatal brain development and cause neurological disease—even when present at low levels of mosaicism, for example—resulting in brain malformations associated with epilepsy and intellectual disability. Novel, highly sensitive technologies will allow more accurate evaluation of somatic mutations in neurodevelopmental disorders and during normal brain development. PMID:23828942

  20. Expression of the Hsp23 chaperone during Drosophila embryogenesis: association to distinct neural and glial lineages

    PubMed Central

    Michaud, Sébastien; Tanguay, Robert M

    2003-01-01

    Background In addition to their strong induction following stress, small heat shock proteins (Hsp) are also expressed during development in a wide variety of organisms. However, the precise identity of cell(s) expressing these proteins and the functional contribution of small heat shock proteins in such developmental context remain to be determined. The present study provides a detailed description of the Drosophila small heat shock protein Hsp23 expression pattern during embryogenesis and evaluates its functional contribution to central nervous system development. Results Throughout embryogenesis, Hsp23 is expressed in a stage-specific manner by a restricted number of neuronal and glial lineages of the central nervous system. Hsp23 is also detected in the amnioserosa and within a single lateral chordotonal organ. Its expression within the MP2 lineage does not require the presence of a functional midline nor the activity of the Notch signaling pathway. Transactivation assays demonstrate that transcription factors implicated in the differentiation of the midline also regulate hsp23 promoter activity. Phenotypic analysis of a transgenic line exhibiting loss of Hsp23 expression in the central nervous system suggests that Hsp23 is not required for development and function of this tissue. Likewise, its overexpression does not cause deleterious effects, as development remains unaffected. Conclusions Based on the presented data, we suggest that the tightly regulated developmental expression of Hsp23 is not actively involved in cell differentiation and central nervous system development per se but rather reflects a putative role in preventive "pre-stress" neuroprotection or in non-vital process(es) common to the identified cell lineages. PMID:14617383

  1. The effects of Ostertagia occidentalis somatic antigens on ovine TLR2 and TLR4 expression

    PubMed Central

    BORJI, Hassan; HAGHPARAST, Alireza; SOLEIMANI, Nooshinmehr; AZIZZADEH, Mohammad; NAZEMSHIRAZI, Mohammad Hossein

    2015-01-01

    Background: Recognition of helminth-derived pathogen associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs), including toll like receptors (TLRs) is the first step towards initiating anti–helminth immune responses. Methods : Using somatic antigens of Ostertagia occidentalis, an important abomasal parasite of ruminants, the expression of ovine TLR2 and TLR4 in peripheral blood mononuclear cells (PBMCs) was analyzed by real-time quatitative reverse-transcription polymerase chain reaction (qRT-PCR). Somatic antigens of O. occidentalis were prepared to stimulate ovine PBMCs in a time and dose dependent manner. Results : A high expression of TLR2 and TLR4 was observed in PBMCs cultured with somatic antigens of the parasites specially when PBMCs were cultured with 100 µg/ml of somatic antigens and incubated for 2h. Up-regulation of TLR2 expression was more pronounced and evident in our study. Conclsusion : Somatic antigens of O. occidentalis have immunostimulatory and dominant role on peripheral immune cells. This study provide for the first time evidence of induction of TLRs in ovine PBMCs by somatic antigen of O. occidentalis PMID:26622306

  2. Molecular Aspects of Conifer Zygotic and Somatic Embryo Development: A Review of Genome-Wide Approaches and Recent Insights.

    PubMed

    Trontin, Jean-François; Klimaszewska, Krystyna; Morel, Alexandre; Hargreaves, Catherine; Lelu-Walter, Marie-Anne

    2016-01-01

    Genome-wide profiling (transcriptomics, proteomics, metabolomics) is providing unprecedented opportunities to unravel the complexity of coordinated gene expression during embryo development in trees, especially conifer species harboring "giga-genome." This knowledge should be critical for the efficient delivery of improved varieties through seeds and/or somatic embryos in fluctuating markets and to cope with climate change. We reviewed "omics" as well as targeted gene expression studies during both somatic and zygotic embryo development in conifers and tentatively puzzled over the critical processes and genes involved at the specific developmental and transition stages. Current limitations to the interpretation of these large datasets are going to be lifted through the ongoing development of comprehensive genome resources in conifers. Nevertheless omics already confirmed that master regulators (e.g., transcription and epigenetic factors) play central roles. As in model angiosperms, the molecular regulation from early to late embryogenesis may mainly arise from spatiotemporal modulation of auxin-, gibberellin-, and abscisic acid-mediated responses. Omics also showed the potential for the development of tools to assess the progress of embryo development or to build genotype-independent, predictive models of embryogenesis-specific characteristics. PMID:26619863

  3. Cracking the egg: virtual embryogenesis of real robots.

    PubMed

    Cussat-Blanc, Sylvain; Pollack, Jordan

    2014-01-01

    All multicellular living beings are created from a single cell. A developmental process, called embryogenesis, takes this first fertilized cell down a complex path of reproduction, migration, and specialization into a complex organism adapted to its environment. In most cases, the first steps of the embryogenesis take place in a protected environment such as in an egg or in utero. Starting from this observation, we propose a new approach to the generation of real robots, strongly inspired by living systems. Our robots are composed of tens of specialized cells, grown from a single cell using a bio-inspired virtual developmental process. Virtual cells, controlled by gene regulatory networks, divide, migrate, and specialize to produce the robot's body plan (morphology), and then the robot is manually built from this plan. Because the robot is as easy to assemble as Lego, the building process could be easily automated. PMID:24730763

  4. Essential elements for translation: the germline factor Vasa functions broadly in somatic cells.

    PubMed

    Yajima, Mamiko; Wessel, Gary M

    2015-06-01

    Vasa is a conserved RNA-helicase found in the germ lines of all metazoans tested. Whereas Vasa presence is often indicated as a metric for germline determination in animals, it is also expressed in stem cells of diverse origin. Recent research suggests, however, that Vasa has a much broader function, including a significant role in cell cycle regulation. Results herein indicate that Vasa is utilized widely, and often induced transiently, during development in diverse somatic cells and adult precursor tissues. We identified that Vasa in the sea urchin is essential for: (1) general mRNA translation during embryogenesis, (2) developmental re-programming upon manipulations to the embryo and (3) larval wound healing. We also learned that Vasa interacted with mRNAs in the perinuclear area and at the spindle in an Importin-dependent manner during cell cycle progression. These results suggest that, when present, Vasa functions are essential to contributing to developmental regulation. PMID:25977366

  5. Interactions between ?-tocopherol, polyunsaturated fatty acids, and lipoxygenases during embryogenesis.

    PubMed

    Lebold, Katie M; Traber, Maret G

    2014-01-01

    ?-Tocopherol is a lipid-soluble antioxidant that is specifically required for reproduction and embryogenesis. However, since its discovery, ?-tocopherol's specific biologic functions, other than as an antioxidant, and the mechanism(s) mediating its requirement for embryogenesis remain unknown. As an antioxidant, ?-tocopherol protects polyunsaturated fatty acids (PUFAs) from lipid peroxidation. ?-Tocopherol is probably required during embryonic development to protect PUFAs that are crucial to development, specifically arachidonic (ARA) and docosahexaenoic (DHA) acids. Additionally, ARA and DHA are metabolized to bioactive lipid mediators via lipoxygenase enzymes, and ?-tocopherol may directly protect, or it may mediate the production and/or actions of, these lipid mediators. In this review, we discuss how ?-tocopherol (1) prevents the nonspecific, radical-mediated peroxidation of PUFAs, (2) functions within a greater antioxidant network to modulate the production and/or function of lipid mediators derived from 12- and 12/15-lipoxygenases, and (3) modulates 5-lipoxygenase activity. The application and implication of such interactions are discussed in the context of ?-tocopherol requirements during embryogenesis. PMID:23920314

  6. Mcm10 is required for oogenesis and early embryogenesis in Drosophila.

    PubMed

    Reubens, Michael C; Biller, Megan D; Bedsole, Sidney E; Hopkins, Lucas T; Ables, Elizabeth T; Christensen, Tim W

    2015-11-01

    Efficient replication of the genome and the establishment of endogenous chromatin states are processes that are essential to eukaryotic life. It is well documented that Mcm10 is intimately linked to both of these important biological processes; therefore, it is not surprising that Mcm10 is commonly misregulated in many human cancers. Most of the research regarding the biological roles of Mcm10 has been performed in single-cell or cell-free in-vitro systems. Though these systems are informative, they are unable to provide information on the cell-specific function of Mcm10 in the context of the tissue and organ systems that comprise multicellular eukaryotes. We therefore sought to identify the potential biological functions of Mcm10 in the context of a complex multicellular organism by continuing our analysis in Drosophila using three novel hypomorphic alleles. Observation of embryonic nuclear morphology and quantification of embryo hatch rates reveal that maternal loading of Mcm10 is required for embryonic nuclear stability, and suggest a role for Mcm10 post zygotic transition. Contrary to the essential nature of Mcm10 depicted in the literature, it does not appear to be required for adult viability in Drosophila if embryonic requirements are met. Although not required for adult somatic viability, analysis of fecundity and ovarian morphology in mutant females suggest that Mcm10 plays a role in maintenance of the female germline. Taken together, our results demonstrate critical roles for Mcm10 during early embryogenesis, and mark the first data linking Mcm10 to female specific reproduction in multicellular eukaryotes. PMID:26369283

  7. PlantCellReports (1993)12:125-128 Repetitive somatic embryogenesis and plant recovery in white clover

    E-print Network

    Parrott, Wayne

    1993-01-01

    clover A. KeytonWeissingerII andWayneA. Parrott Departmentof Agronomy,The Universityof Georgia Swnmary. Breedingand selectionwasusedto generate a populationof white clover (Trifolium repensL.) from, and inclusionor exclusionof activatedcharcoalwereevaluated. Repeatedsubcultureof white clover somaticembryoson EC6

  8. Biochemical Relationship Between Otolith and Somatic

    E-print Network

    Biochemical Relationship Between Otolith and Somatic Growth in the Rainbow Trout Oncorhynchus- ination of otolith growth-somatic growth relationship was conducted in rainbow trout Oncorhynchu.s my- kiss. The rate of otolith growth was defined by calcium deposition on oto- liths in an in 11it

  9. Somatic Mosaicism in the Human Genome

    PubMed Central

    Freed, Donald; Stevens, Eric L.; Pevsner, Jonathan

    2014-01-01

    Somatic mosaicism refers to the occurrence of two genetically distinct populations of cells within an individual, derived from a postzygotic mutation. In contrast to inherited mutations, somatic mosaic mutations may affect only a portion of the body and are not transmitted to progeny. These mutations affect varying genomic sizes ranging from single nucleotides to entire chromosomes and have been implicated in disease, most prominently cancer. The phenotypic consequences of somatic mosaicism are dependent upon many factors including the developmental time at which the mutation occurs, the areas of the body that are affected, and the pathophysiological effect(s) of the mutation. The advent of second-generation sequencing technologies has augmented existing array-based and cytogenetic approaches for the identification of somatic mutations. We outline the strengths and weaknesses of these techniques and highlight recent insights into the role of somatic mosaicism in causing cancer, neurodegenerative, monogenic, and complex disease. PMID:25513881

  10. Perfluoroheptanoic acid affects amphibian embryogenesis by inducing the phosphorylation of ERK and JNK.

    PubMed

    Kim, Miran; Park, Mi Seon; Son, Jungeun; Park, Inji; Lee, Hyun-Kyung; Kim, Chowon; Min, Byung-Hwa; Ryoo, Jaewoong; Choi, Kwang Shik; Lee, Dong-Seok; Lee, Hyun-Shik

    2015-12-01

    Perfluoroalkyl compounds (PFCs) are globally distributed synthetic compounds that are known to adversely affect human health. Developmental toxicity assessment of PFCs is important to facilitate the evaluation of their environmental impact. In the present study, we assessed the developmental toxicity and teratogenicity of PFCs with different numbers of carbon atoms on Xenopus embryogenesis. An initial frog embryo teratogenicity assay-Xenopus (FETAX) assay was performed that identified perfluorohexanoic (PFHxA) and perfluoroheptanoic (PFHpA) acids as potential teratogens and developmental toxicants. The mechanism underlying this teratogenicity was also investigated by measuring the expression of tissue-specific biomarkers such as phosphotyrosine?binding protein, xPTB (liver); NKX2.5 (heart); and Cyl18 (intestine). Whole?mount in situ hybridization, reverse transcriptase?polymerase chain reaction (RT-PCR), and histologic analyses detected severe defects in the liver and heart following exposure to PFHxA or PFHpA. In addition, immunoblotting revealed that PFHpA significantly increased the phosphorylation of extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK), while PFHxA slightly increased these, as compared with the control. These results suggest that PFHxA and PFHpA are developmental toxicants and teratogens, with PFHpA producing more severe effects on liver and heart development through the induction of ERK and JNK phosphorylation. PMID:26459765

  11. The use of centrifugation to study early Drosophila embryogenesis

    NASA Technical Reports Server (NTRS)

    Abbott, M. K.; Spooner, B. S. (Principal Investigator)

    1993-01-01

    By the end of 10th nuclear cycle, the somatic nuclei of the Drosophila embryo have migrated to the periphery of the egg. Centrifugation of embryos did not result in the displacement of these nuclei, since cytoskeletal elements anchor them to the cortex. But, mild centrifugal forces displace the centrally located, nascent yolk nuclei. If this increased sensitivity to hypergravity occurs before the beginning of nuclear differentiation during cycle 8, when the nascent yolk and somatic nuclei physically separate, then it would mark the earliest functional difference between these two lineages.

  12. Epithelial self-organization in fruit fly embryogenesis

    NASA Astrophysics Data System (ADS)

    Hutson, M. Shane

    2010-03-01

    During fruit fly embryogenesis, there are several morphogenetic events in which sheets of epithelial cells expand, contract and bend due to coordinated intra- and intercellular forces. This tissue-level reshaping is accompanied by changes in the shape and arrangement of individual cells -- changes that can be measured quantitatively and dynamically using modern live-cell imaging techniques. Such data sets represent rich targets for computational modeling of self-organization; however, reproducing the observed cell- and tissue-level reshaping is not enough. The inverse problem of using cell shape changes to determine cell-level forces is ill-posed -- yielding non-unique solutions that cannot discriminate between active changes in cell shape and passive deformation. These non-unique solutions can be tested experimentally using in vivo laser-microsurgery -- i.e., cutting a targeted region of an epithelium and carefully tracking the temporal and spatial dependence of the subsequent strain relaxation. This technique uses a variety of incisions (hole, line or closed curve) to probe different aspects of epithelial mechanics: the local mesoscopic strain; the distribution of intracellular forces; changes in the cell-level power-law rheology; and the question of active versus passive deformation. I will discuss my group's work using laser-microsurgery to investigate two morphogenetic events in fruit fly embryogenesis: germband retraction and dorsal closure. In both cases, we find a substantial active mechanical role for the amnioserosa -- an epithelium that undergoes apoptosis near the end of embryogenesis and makes no part of the fly larva -- in reshaping an adjacent epithelium that becomes the larval epidermis. In these examples, self-organization of the fly embryo relies not only on self-organization of individual tissues, but also on the mechanical interactions between tissues.

  13. Early Zebrafish Embryogenesis Is Susceptible to Developmental TDCPP Exposure

    PubMed Central

    McGee, Sean P.; Cooper, Ellen M.; Stapleton, Heather M.

    2012-01-01

    Background: Chlorinated phosphate esters (CPEs) are widely used as additive flame retardants for low-density polyurethane foams and have frequently been detected at elevated concentrations within indoor environmental media. Objectives: To begin characterizing the potential toxicity of CPEs on early vertebrate development, we examined the developmental toxicity of four CPEs used in polyurethane foam: tris(1,3-dichloro-2-propyl) phosphate (TDCPP), tris(2-chloroethyl) phosphate (TCEP), tris(1-chloro-2-propyl) phosphate (TCPP), and 2,2-bis(chloromethyl)propane-1,3-diyl tetrakis(2-chlorethyl) bis(phosphate) (V6). Methods: Using zebrafish as a model for vertebrate embryogenesis, we first screened the potential teratogenic effects of TDCPP, TCEP, TCPP, and V6 using a developmental toxicity assay. Based on these results, we focused on identification of susceptible windows of developmental TDCPP exposure as well as evaluation of uptake and elimination of TDCPP and bis(1,3-dichloro-2-propyl)phosphate (BDCPP, the primary metabolite) within whole embryos. Finally, because TDCPP-specific genotoxicity assays have, for the most part, been negative in vivo and because zygotic genome remethylation is a key biological event during cleavage, we investigated whether TDCPP altered the status of zygotic genome methylation during early zebrafish embryogenesis. Results: Overall, our findings suggest that the cleavage period during zebrafish embryogenesis is susceptible to TDCPP-induced delays in remethylation of the zygotic genome, a mechanism that may be associated with enhanced developmental toxicity following initiation of TDCPP exposure at the start of cleavage. Conclusions: Our results suggest that further research is needed to better understand the effects of a widely used and detected CPE within susceptible windows of early vertebrate development. PMID:23017583

  14. Somatic Complaints and Chinese-American Adolescents: Examining the Role of Parent-child Relationships 

    E-print Network

    Kao, Grace Sung-Tzu

    2013-06-05

    in response to the child?s undesired behaviors. Forms of this type of control have been identified by Barber and Harmon (2002) as guilt induction, love withdrawal, instilling anxiety, and invalidation of the child?s perspective. Parental psychological...-1 SOMATIC COMPLAINTS AND CHINESE-AMERICAN ADOLESCENTS: EXAMINING THE ROLE OF PARENT-CHILD RELATIONSHIPS A Dissertation by GRACE S. KAO Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements...

  15. Abscisic acid and sucrose increase the protein content in date palm somatic embryos, causing changes in 2-DE profile.

    PubMed

    Sghaier-Hammami, Besma; Jorrín-Novo, Jesús V; Gargouri-Bouzid, Radhia; Drira, Noureddine

    2010-08-01

    Various supplements (abscisic acid (ABA) or sucrose) were added to the initial embryo culture medium (M3) with the aim of improving the vigour of vitroplants deriving from date palm somatic embryogenesis. ABA (20 and 40 microM) and sucrose (90 g/l) applied for 4 and 2 weeks respectively increased embryo thickness, with no apparent difference in length. ABA (5-40 microM) increased embryo proliferation rate. Somatic embryos maintained in modified M3 (M3 supplemented with ABA and an increased sucrose concentration) contained a higher amount of protein than those maintained in initial M3 (no ABA, 30 g/l of sucrose), with a 1.5-1.7-fold increase depending on the compound and concentration assayed. The 1-D and 2-DE protein profiles showed qualitative and quantitative differences between the somatic embryos cultured in initial M3 (control) and in modified M3. Statistical analysis of spot intensity was performed by principal component analysis, yielding two accurate groups of samples and determining the most discriminating spots. Samples were also clustered using Euclidean distance with an average linkage algorithm. Thirty-four variable spots were identified using mass spectrometry analysis. Identified proteins were classified into the following functional categories: energy metabolism (five proteins); protein translation, folding and degradation (9); redox maintenance (5); cytoskeleton (3); storage protein (2); and with no assigned function as (10). While "up-regulation" of stress-related proteins and "down-regulation" of energy metabolism proteins were observed in somatic embryos matured in M3 supplemented with ABA, storage proteins (legumin) were "up-regulated" in somatic embryos matured in M3 supplemented with increased sucrose. PMID:20605176

  16. Comparison of developmental trajectories in the starlet sea anemone Nematostella vectensis: embryogenesis, regeneration,

    E-print Network

    Finnerty, John R.

    reproduction, (2) asexual reproduction via physal pinching, (3) asexual reproduction via polarity reversal sequences of embryogenesis, asexual reproduction, and regenera- tion have not been explicitly compared: embryogenesis, regeneration, and two forms of asexual fission Adam M. Reitzel, Patrick M. Burton, Cassandra

  17. Expression of the c-ret proto-oncogene during mouse embryogenesis.

    PubMed

    Pachnis, V; Mankoo, B; Costantini, F

    1993-12-01

    The c-ret proto-oncogene encodes a receptor tyrosine kinase whose normal function has yet to be determined. To begin to investigate the potential role of this gene in vertebrate development, we have isolated cDNA clones representing the murine c-ret gene, and have analyzed the pattern of expression during mouse embryogenesis, using northern blotting, in situ hybridization to histological sections and whole-mount hybridization histochemistry. c-ret transcripts were detected beginning at day 8.5 of embryogenesis, and were observed in a number of cell lineages in the developing peripheral and central nervous systems, as well as in the excretory system. In the cranial region at day 8.5-9.5, c-ret mRNA was restricted to a population of neural crest cells migrating from rhombomere 4 and forming the anlage of the facioacoustic ganglion, as well as to a closely associated domain of surface ectoderm and pharyngeal endoderm. At later stages (10.5-14.5 days), c-ret mRNA was observed in all cranial ganglia. In the peripheral nervous system of the trunk, c-ret was expressed in the autonomic ganglia and in subsets of cells in the dorsal root ganglia. In the enteric nervous system, c-ret was expressed in the presumptive enteric neuroblasts of the vagal crest (day 9.0-11.5), and in the myenteric ganglia of the gut (day 13.5-14.5). c-ret mRNA was observed in several regions of the central nervous system, including the undifferentiated neuroepithelial cells of the ventral neural tube (8.5 days), the motor neurons in the spinal cord and the hindbrain (10.5-14.5 days), the embryonic neuroretina (day 13.5) and the layers of the postnatal retina containing ganglion, amacrine and horizontal cells. Outside the nervous system, c-ret was expressed in the nephric (Wolffian) duct at day 8.5-10.5, the ureteric bud epithelium (but not the surrounding metanephric mesenchyme) at day 11.0-11.5, and the growing tips of the renal collecting ducts (but not the previously formed, subcortical portions of the collecting ducts, or the mesenchyme-derived renal vesicles) at day 13.5-17.5. Our results suggest that the c-ret gene may encode the receptor for a factor involved in the proliferation, migration, differentiation or survival of a variety of neuronal cell lineages, as well as in inductive interactions during organogenesis of the kidney. PMID:8306871

  18. Expression of strawberry notch family genes during zebrafish embryogenesis.

    PubMed

    Takano, Ai; Zochi, Riyo; Hibi, Masahiko; Terashima, Toshio; Katsuyama, Yu

    2010-06-01

    Our previous study suggested a possible role for Sbno1, a mouse homologue of strawberry notch gene during brain development. In this report, we cloned the zebrafish homologues of sbno, and examined their expression pattern during embryogenesis by whole-mount in situ hybridization. Zebrafish have three sbno genes: one Sbno1 homologue and two Sbno2 homologues, sbno2a and sbno2b. We observed that the expression of sbno1 and sbno2a was initially ubiquitous and gradually became predominant in the central nervous system as development progressed. The expression of sbno2b was observed in non-neural tissues in contrast to the other two genes. sbno1 and sbno2a exhibited higher expression in distinct regions within the nervous system of pharyngula-stage embryos, suggesting possible differing roles for sbno1 and sbno2a during later stages of embryogenesis. Together, the observed gene expression patterns suggest an important role of sbno-family genes during development of the vertebrate central nervous system. PMID:20503374

  19. Knockdown of NLRP5 arrests early embryogenesis in sows.

    PubMed

    Peng, Hui; Liu, Fang; Li, Wenhao; Zhang, Wenchang

    2015-12-01

    NLRP (NLR family, Pyrin domain containing) genes have both immunization- and reproduction-related clades in mammals. Nlrp5 is a reproduction-related gene, originally identified in the mouse, which plays a key role in mouse early embryogenesis. Previous studies estimated that the porcine NLRP5 gene is assigned to the long arm of chromosome 6 and expressed in oocytes. However, the expression pattern of the NLRP5 gene in the porcine reproductive tract, and the localization and function of NLRP5 protein in porcine preimplantation embryos are still unknown. Here, we show that NLRP5 transcripts and protein are detected exclusively in the ovary in the porcine reproductive tract. Furthermore, the transcripts display a sharp decline in porcine preimplantation embryos before zygotic genome activation, but the protein remains present through to the blastocyst stage, localize in the cytoplasm and close to the subcortex of porcine oocytes and preimplantation embryos. Moreover, the knockdown of NLRP5 expression in zygotes using RNA interference arrested early embryonic development. These results provide the first evidence that the NLRP5 gene is required for early embryogenesis in sows, suggesting that this gene might play an essential role in zygotic genome activation. PMID:26585895

  20. Somatic retrotransposition in the cancer genome

    E-print Network

    Helman, Elena

    2014-01-01

    Cancer is a complex disease of the genome exhibiting myriad somatic mutations, from single nucleotide changes to various chromosomal rearrangements. The technological advances of next-generation sequencing enable high-throughput ...

  1. (Somatic mutations in nuclear and mitochondrial DNA)

    SciTech Connect

    Not Available

    1992-01-01

    The study is concerned the design of new assays that may detect rare somatic mutations in nuclear and mitochondrial DNA, which may increase upon exposure to mutagens, and thus become a marker of human exposure to such mutagens. Two assays for somatic mutation were presented, one for mitochondrial DNA deletions which was developed by the author, and one for deletions of the ADA gene which resides in the nucleus.

  2. Human somatic cell nuclear transfer and cloning.

    PubMed

    2012-10-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer (cloning)," last published in Fertil Steril 2000;74:873-6. PMID:22795681

  3. Somatic Complaints in Anxious Youth

    PubMed Central

    Crawley, Sarah A.; Caporino, Nicole E.; Birmaher, Boris; Ginsburg, Golda; Piacentini, John; Albano, Anne Marie; Sherrill, Joel; Sakolsky, Dara; Compton, Scott N.; Rynn, Moira; McCracken, James; Gosch, Elizabeth; Keeton, Courtney; March, John; Walkup, John T.; Kendall, Philip C.

    2013-01-01

    This study examined (a) demographic and clinical characteristics associated with physical symptoms in anxiety-disordered youth and (b) the impact of cognitive-behavioral therapy (Coping Cat), medication (sertraline), their combination, and pill placebo on physical symptoms. Youth (N = 488, ages 7–17 years) with a principal diagnosis of generalized anxiety disorder, separation anxiety disorder, or social phobia participated as part of a multi-site, randomized controlled trial and received treatment delivered over 12 weeks. Diagnostic status, symptom severity, and impairment were assessed at baseline and week 12. The total number and severity of physical symptoms was associated with age, principal diagnosis, anxiety severity, impairment, and the presence of comorbid internalizing disorders. Common somatic complaints were headaches, stomachaches, head cold or sniffles, sleeplessness, and feeling drowsy or too sleepy. Physical symptoms decreased over the course of treatment, and were unrelated to treatment condition. Clinical implications and directions for future research are discussed. (ClinicalTrials.gov number, NCT00052078) PMID:24129543

  4. Polyamine and Its Metabolite H2O2 Play a Key Role in the Conversion of Embryogenic Callus into Somatic Embryos in Upland Cotton (Gossypium hirsutum L.)

    PubMed Central

    Cheng, Wen-Han; Wang, Fan-Long; Cheng, Xin-Qi; Zhu, Qian-Hao; Sun, Yu-Qiang; Zhu, Hua-Guo; Sun, Jie

    2015-01-01

    The objective of this study was to increase understanding about the mechanism by which polyamines (PAs) promote the conversion of embryogenic calli (EC) into somatic embryos in cotton (Gossypium hirsutum L.). We measured the levels of endogenous PAs and H2O2, quantified the expression levels of genes involved in the PAs pathway at various stages of cotton somatic embryogenesis (SE), and investigated the effects of exogenous PAs and H2O2 on differentiation and development of EC. Putrescine (Put), spermidine (Spd), and spermine (Spm) significantly increased from the EC stage to the early phase of embryo differentiation. The levels of Put then decreased until the somatic embryo stage whereas Spd and Spm remained nearly the same. The expression profiles of GhADC genes were consistent with changes in Put during cotton SE. The H2O2 concentrations began to increase significantly at the EC stage, during which time both GhPAO1 and GhPAO4 expressions were highest and PAO activity was significantly increased. Exogenous Put, Spd, Spm, and H2O2 not only enhanced embryogenic callus growth and embryo formation, but also alleviated the effects of D-arginine and 1, 8-diamino-octane, which are inhibitors of PA synthesis and PAO activity. Overall, the results suggest that both PAs and their metabolic product H2O2 are essential for the conversion of EC into somatic embryos in cotton. PMID:26697030

  5. Induction voidmeter

    DOEpatents

    Anderson, T.T.; Roop, C.J.; Schmidt, K.J.; Brewer, J.

    1983-12-21

    An induction voidmeter for detecting voids in a conductive fluid may comprise: a four arm bridge circuit having two adjustable circuit elements connected as opposite arms of said bridge, an input branch, and an output branch; two induction coils, bifilarly wound together, connected as the remaining two opposing arms of said bridge circuit and positioned such that the conductive fluid passes through said coils; means for applying an AC excitation signal to said input branch; and means for detecting the output signal generated in response to said excitation signal across said output branch. The induction coils may be located outside or inside a non-magnetic pipe containing the conductive fluid.

  6. Induction voidmeter

    DOEpatents

    Anderson, Thomas T. (Downers Grove, IL); Roop, Conard J. (Lockport, IL); Schmidt, Kenneth J. (Midlothian, IL); Brewer, John (Oak Lawn, IL)

    1986-01-01

    An induction voidmeter for detecting voids in a conductive fluid may comprise: a four arm bridge circuit having two adjustable circuit elements connected as opposite arms of said bridge circuit, an input branch, and an output branch; two induction coils, bifilarly wound together, connected as the remaining two opposing arms of said bridge circuit and positioned such that the conductive fluid passes through said coils; applying an AC excitation signal to said input branch; and detecting the output signal generated in response to said excitation signal across said output branch. The induction coils may be located outside or inside a non-magnetic pipe containing the conductive fluid.

  7. Wild worm embryogenesis harbors ubiquitous polygenic modifier variation.

    PubMed

    Paaby, Annalise B; White, Amelia G; Riccardi, David D; Gunsalus, Kristin C; Piano, Fabio; Rockman, Matthew V

    2015-01-01

    Embryogenesis is an essential and stereotypic process that nevertheless evolves among species. Its essentiality may favor the accumulation of cryptic genetic variation (CGV) that has no effect in the wild-type but that enhances or suppresses the effects of rare disruptions to gene function. Here, we adapted a classical modifier screen to interrogate the alleles segregating in natural populations of Caenorhabditis elegans: we induced gene knockdowns and used quantitative genetic methodology to examine how segregating variants modify the penetrance of embryonic lethality. Each perturbation revealed CGV, indicating that wild-type genomes harbor myriad genetic modifiers that may have little effect individually but which in aggregate can dramatically influence penetrance. Phenotypes were mediated by many modifiers, indicating high polygenicity, but the alleles tend to act very specifically, indicating low pleiotropy. Our findings demonstrate the extent of conditional functionality in complex trait architecture. PMID:26297805

  8. Current insights into hormonal regulation of microspore embryogenesis

    PubMed Central

    ?ur, Iwona; Dubas, Ewa; Krzewska, Monika; Janowiak, Franciszek

    2015-01-01

    Plant growth regulator (PGR) crosstalk and interaction with the plant’s genotype and environmental factors play a crucial role in microspore embryogenesis (ME), controlling microspore-derived embryo differentiation and development as well as haploid/doubled haploid plant regeneration. The complexity of the PGR network which could exist at the level of biosynthesis, distribution, gene expression or signaling pathways, renders the creation of an integrated model of ME-control crosstalk impossible at present. However, the analysis of the published data together with the results received recently with the use of modern analytical techniques brings new insights into hormonal regulation of this process. This review presents a short historical overview of the most important milestones in the recognition of hormonal requirements for effective ME in the most important crop plant species and complements it with new concepts that evolved over the last decade of ME studies. PMID:26113852

  9. Embryogenesis and Plant Regeneration from Isolated Wheat Zygotes.

    PubMed

    Kumlehn, Jochen

    2016-01-01

    Wheat zygotes can be mechanically isolated and cultivated to continue their development in vitro. Since each zygote needs to be individually isolated, only relatively few of these cells are available per experiment. To facilitate embryonic growth despite of this limitation, the zygotes are kept within a culture insert placed in a larger dish which itself contains embryogenic pollen cocultivated for continuous medium conditioning. This setup ensures that the two cultures, while being physically separated from one another, can exchange essential intercellular signal molecules passing through the bottom of the insert which is made of a permeable membrane. Thanks to the natural fate of zygotes, which is to form an embryo followed by the generation of a plant, embryogenesis and plant regeneration are achieved at much higher efficiency as compared to other single-cell systems. While the method is largely independent of the genotype, it allows for the nondestructive observation, manipulation, and individual analysis of zygotes and very young embryos. PMID:26619884

  10. Differential expression of two scribble isoforms during Drosophila embryogenesis.

    PubMed

    Li, M; Marhold, J; Gatos, A; Török, I; Mechler, B M

    2001-10-01

    The tumour suppressor gene scribble (scrib) is required for epithelial polarity and growth control in Drosophila. Here, we report the identification and embryonic expression pattern of two Scrib protein isoforms resulting from alternative splicing during scrib transcription. Both proteins are first ubiquitously expressed during early embryogenesis. Then, during morphogenesis each Scrib protein displays a specific pattern of expression in the central and peripheral nervous systems, CNS and PNS, respectively. During germ band extension, the expression of the longer form Scrib1 occurs predominantly in the neuroblasts derived from the neuro-ectoderm and becomes later restricted to CNS neurones as well as to the pole cells in the gonads. By contrast, the shorter form Scrib2 is strongly expressed in the PNS and a subset of CNS neurones. PMID:11578873

  11. Wild worm embryogenesis harbors ubiquitous polygenic modifier variation

    PubMed Central

    Paaby, Annalise B; White, Amelia G; Riccardi, David D; Gunsalus, Kristin C; Piano, Fabio; Rockman, Matthew V

    2015-01-01

    Embryogenesis is an essential and stereotypic process that nevertheless evolves among species. Its essentiality may favor the accumulation of cryptic genetic variation (CGV) that has no effect in the wild-type but that enhances or suppresses the effects of rare disruptions to gene function. Here, we adapted a classical modifier screen to interrogate the alleles segregating in natural populations of Caenorhabditis elegans: we induced gene knockdowns and used quantitative genetic methodology to examine how segregating variants modify the penetrance of embryonic lethality. Each perturbation revealed CGV, indicating that wild-type genomes harbor myriad genetic modifiers that may have little effect individually but which in aggregate can dramatically influence penetrance. Phenotypes were mediated by many modifiers, indicating high polygenicity, but the alleles tend to act very specifically, indicating low pleiotropy. Our findings demonstrate the extent of conditional functionality in complex trait architecture. DOI: http://dx.doi.org/10.7554/eLife.09178.001 PMID:26297805

  12. Eyelid Closure in Embryogenesis Is Required for Ocular Adnexa Development

    PubMed Central

    Meng, Qinghang; Mongan, Maureen; Carreira, Vinicius; Kurita, Hisaka; Liu, Chia-yang; Kao, Winston W.-Y.; Xia, Ying

    2014-01-01

    Purpose. Mammalian eye development requires temporary fusion of the upper and lower eyelids in embryogenesis. Failure of lid closure in mice leads to an eye open at birth (EOB) phenotype. Many genetic mutant strains develop this phenotype and studies of the mutants lead to a better understanding of the signaling mechanisms of morphogenesis. The present study investigates the roles of lid closure in eye development. Methods. Seven mutant mouse strains were generated by different gene ablation strategies that inactivated distinct signaling pathways. These mice, including systemic ablation of Map3k1 and Dkk2, ocular surface epithelium (OSE) knockout of c-Jun and Egfr, conditional knockout of Shp2 in stratified epithelium (SE), as well as the Map3k1/Jnk1 and Map3k1/Rhoa compound mutants, all exhibited defective eyelid closure. The embryonic and postnatal eyes in these mice were characterized by histology and immunohistochemistry. Results. Some eye abnormalities, such as smaller lens in the Map3k1-null mice and Harderian gland hypoplasia in the Dkk2-null mice, appeared to be mutant strain–specific, whereas other abnormalities were seen in all mutants examined. The common defects included corneal erosion/ulceration, meibomian gland hypoplasia, truncation of the eyelid tarsal muscles, failure of levator palpebrae superioris (LPS) extension into the upper eyelid and misplacement of the inferior oblique (IO) muscle and inferior rectus (IR) muscle. The muscle defects were traced to the prenatal fetuses. Conclusions. In addition to providing a protective barrier for the ocular surface, eyelid closure in embryogenesis is required for the development of ocular adnexa, including eyelid and extraocular muscles. PMID:25377219

  13. A Reverse Genetic Approach to Test Functional Redundancy During Embryogenesis

    PubMed Central

    Rikin, Amir; Rosenfeld, Gabriel E.; McCartin, Kellie; Evans, Todd

    2010-01-01

    Gene function during embryogenesis is typically defined by loss-of-function experiments, for example by targeted mutagenesis (knockout) in the mouse. In the zebrafish model, effective reverse genetic techniques have been developed using microinjection of gene-specific antisense morpholinos. Morpholinos target an mRNA through specific base-pairing and block gene function transiently by inhibiting translation or splicing for several days during embryogenesis (knockdown). However, in vertebrates such as mouse or zebrafish, some gene functions can be obscured by these approaches due to the presence of another gene that compensates for the loss. This is especially true for gene families containing sister genes that are co-expressed in the same developing tissues. In zebrafish, functional compensation can be tested in a relatively high-throughput manner, by co-injection of morpholinos that target knockdown of both genes simultaneously. Likewise, using morpholinos, a genetic interaction between any two genes can be demonstrated by knockdown of both genes together at sub-threshold levels. For example, morpholinos can be titrated such that neither individual knockdown generates a phenotype. If, under these conditions, co-injection of both morpholinos causes a phenotype, a genetic interaction is shown. Here we demonstrate how to show functional redundancy in the context of two related GATA transcription factors. GATA factors are essential for specification of cardiac progenitors, but this is revealed only by the loss of both Gata5 and Gata6. We show how to carry out microinjection experiments, validate the morpholinos, and evaluate the compensated phenotype for cardiogenesis. PMID:20736915

  14. Knockdown of Brm and Baf170, Components of Chromatin Remodeling Complex, Facilitates Reprogramming of Somatic Cells.

    PubMed

    Jiang, Zongliang; Tang, Yong; Zhao, Xueming; Zhang, Mingyuan; Donovan, David M; Tian, Xiuchun Cindy

    2015-10-01

    The SWI/SNF (SWItch/Sucrose NonFermentable or BAF, Brg/Brahma-associated factors) complexes are epigenetic modifiers of chromatin structure and undergo progressive changes in subunit composition during cellular differentiation. For example, in embryonic stem cells, esBAF contains Brg1 and Baf155, while their homologs, Brm and Baf170, are present in BAF of somatic cells. In this study, we sought to determine whether Brm and Baf170 play any roles in induced pluripotent stem cell (iPSC) reprogramming by using shRNA-mediated knockdown studies in the mouse model. We found that knocking down Brm during early, mid, and late stages (days 3, 6, and 9 after initial iPSC induction) and knocking down Baf170 during late-stage (day 9) reprogramming improve the numbers of iPSC colonies formed. We further showed that inhibition of these somatic BAF components also promotes complete reprogramming of partially reprogrammed somatic cells (pre-iPSCs). Finally, we found that the expression of Brm and Baf170 during reprogramming was regulated by Jak/Stat3 activity. Taken together, these data suggest that inhibiting somatic BAF improves complete reprogramming by facilitating the activation of the pluripotency circuitry. PMID:26121422

  15. Somatic Mutations in Cerebral Cortical Malformations

    PubMed Central

    Jamuar, Saumya S.; Lam, Anh-Thu N.; Kircher, Martin; D'Gama, Alissa M.; Wang, Jian; Barry, Brenda J.; Zhang, Xiaochang; Hill, Robert Sean; Partlow, Jennifer N.; Rozzo, Aldo; Servattalab, Sarah; Mehta, Bhaven K.; Topcu, Meral; Amrom, Dina; Andermann, Eva; Dan, Bernard; Parrini, Elena; Guerrini, Renzo; Scheffer, Ingrid E.; Berkovic, Samuel F.; Leventer, Richard J.; Shen, Yiping; Wu, Bai Lin; Barkovich, A. James; Sahin, Mustafa; Chang, Bernard S.; Bamshad, Michael; Nickerson, Deborah A.; Shendure, Jay; Poduri, Annapurna; Yu, Timothy W.; Walsh, Christopher A.

    2014-01-01

    BACKGROUND Although there is increasing recognition of the role of somatic mutations in genetic disorders, the prevalence of somatic mutations in neurodevelopmental disease and the optimal techniques to detect somatic mosaicism have not been systematically evaluated. METHODS Using a customized panel of known and candidate genes associated with brain malformations, we applied targeted high-coverage sequencing (depth, ?200×) to leukocyte-derived DNA samples from 158 persons with brain malformations, including the double-cortex syndrome (subcortical band heterotopia, 30 persons), polymicrogyria with megalencephaly (20), periventricular nodular heterotopia (61), and pachygyria (47). We validated candidate mutations with the use of Sanger sequencing and, for variants present at unequal read depths, subcloning followed by colony sequencing. RESULTS Validated, causal mutations were found in 27 persons (17%; range, 10 to 30% for each phenotype). Mutations were somatic in 8 of the 27 (30%), predominantly in persons with the double-cortex syndrome (in whom we found mutations in DCX and LIS1), persons with periventricular nodular heterotopia (FLNA), and persons with pachygyria (TUBB2B). Of the somatic mutations we detected, 5 (63%) were undetectable with the use of traditional Sanger sequencing but were validated through subcloning and subsequent sequencing of the subcloned DNA. We found potentially causal mutations in the candidate genes DYNC1H1, KIF5C, and other kinesin genes in persons with pachygyria. CONCLUSIONS Targeted sequencing was found to be useful for detecting somatic mutations in patients with brain malformations. High-coverage sequencing panels provide an important complement to whole-exome and whole-genome sequencing in the evaluation of somatic mutations in neuropsychiatric disease. (Funded by the National Institute of Neurological Disorders and Stroke and others.) PMID:25140959

  16. Induction of pluripotency.

    PubMed

    Heffernan, Corey; Liu, Jun; Sumer, Huseyin; Malaver-Ortega, Luis F; Verma, Rajneesh; Carvalho, Edmund; Verma, Paul J

    2013-01-01

    The molecular and phenotypic irreversibility of mammalian cell differentiation was a fundamental principle of developmental biology at least until the 1980s, despite numerous reports dating back to the 1950s of the induction of pluripotency in amphibian cells by nuclear transfer (NT). Landmark reports in the 1980s and 1990s in sheep progressively challenged this dogmatic assumption; firstly, embryonic development of reconstructed embryos comprising whole (donor) blastomeres fused to enucleated oocytes, and famously, the cloning of Dolly from a terminally differentiated cell. Thus, the intrinsic ability of oocyte-derived factors to reverse the differentiated phenotype was confirmed. The concomitant elucidation of methods for human embryonic stem cell isolation and cultivation presented opportunities for therapeutic cell replacement strategies, particularly through NT of patient nuclei to enucleated oocytes for subsequent isolation of patient-specific (autologous), pluripotent cells from the resulting blastocysts. Associated logistical limitations of working with human oocytes, in addition to ethical and moral objections prompted exploration of alternative approaches to generate autologous stem cells for therapy, utilizing the full repertoire of factors characteristic of pluripotency, primarily through cell fusion and use of pluripotent cell extracts. Stunningly, in 2006, Japanese scientists described somatic cell reprogramming through delivery of four key factors (identified through a deductive approach from 24 candidate genes). Although less efficient than previous approaches, much of current stem cell research adopts this focused approach to cell reprogramming and (autologous) cell therapy. This chapter is a quasi-historical commentary of the various aforementioned approaches for the induction of pluripotency in lineage-committed cells, and introduces transcriptional and epigenetic changes occurring during reprogramming. PMID:23696349

  17. Bully victims: psychological and somatic aftermaths.

    PubMed

    Sansone, Randy A; Sansone, Lori A

    2008-06-01

    Bullying is a well-known adversity among school-age children. According to data, approximately 10 percent of US children and adolescents are the victims of frequent bullying by peers. In the aftermath of being bullied, victims may develop a variety of psychological as well as somatic symptoms, some of which may persist into adulthood. Psychological symptoms may include social difficulties, internalizing symptoms, anxiety, depression, suicidal ideation, and eating disorders (i.e., anorexia or bulimia nervosa). Somatic symptoms may include poor appetite, headaches, sleep disturbances, abdominal pain, and fatigue. In both mental health and primary care settings, being aware of these types of psychological and somatic symptoms in vulnerable children and adolescents may expedite the identification and eradication of these abusive experiences.This ongoing column is dedicated to the challenging clinical interface between psychiatry and primary care-two fields that are inexorably linked. PMID:19727287

  18. Somatic mutation in cancer and normal cells.

    PubMed

    Martincorena, Iñigo; Campbell, Peter J

    2015-09-25

    Spontaneously occurring mutations accumulate in somatic cells throughout a person's lifetime. The majority of these mutations do not have a noticeable effect, but some can alter key cellular functions. Early somatic mutations can cause developmental disorders, whereas the progressive accumulation of mutations throughout life can lead to cancer and contribute to aging. Genome sequencing has revolutionized our understanding of somatic mutation in cancer, providing a detailed view of the mutational processes and genes that drive cancer. Yet, fundamental gaps remain in our knowledge of how normal cells evolve into cancer cells. We briefly summarize a number of the lessons learned over 5 years of cancer genome sequencing and discuss their implications for our understanding of cancer progression and aging. PMID:26404825

  19. Coherent Somatic Mutation in Autoimmune Disease

    PubMed Central

    Ross, Kenneth Andrew

    2014-01-01

    Background Many aspects of autoimmune disease are not well understood, including the specificities of autoimmune targets, and patterns of co-morbidity and cross-heritability across diseases. Prior work has provided evidence that somatic mutation caused by gene conversion and deletion at segmentally duplicated loci is relevant to several diseases. Simple tandem repeat (STR) sequence is highly mutable, both somatically and in the germ-line, and somatic STR mutations are observed under inflammation. Results Protein-coding genes spanning STRs having markers of mutability, including germ-line variability, high total length, repeat count and/or repeat similarity, are evaluated in the context of autoimmunity. For the initiation of autoimmune disease, antigens whose autoantibodies are the first observed in a disease, termed primary autoantigens, are informative. Three primary autoantigens, thyroid peroxidase (TPO), phogrin (PTPRN2) and filaggrin (FLG), include STRs that are among the eleven longest STRs spanned by protein-coding genes. This association of primary autoantigens with long STR sequence is highly significant (). Long STRs occur within twenty genes that are associated with sixteen common autoimmune diseases and atherosclerosis. The repeat within the TTC34 gene is an outlier in terms of length and a link with systemic lupus erythematosus is proposed. Conclusions The results support the hypothesis that many autoimmune diseases are triggered by immune responses to proteins whose DNA sequence mutates somatically in a coherent, consistent fashion. Other autoimmune diseases may be caused by coherent somatic mutations in immune cells. The coherent somatic mutation hypothesis has the potential to be a comprehensive explanation for the initiation of many autoimmune diseases. PMID:24988487

  20. The psychological significance of somatic complaints.

    PubMed

    Anstett, R; Collins, M

    1982-02-01

    Patients experiencing psychological distress often come to their physicians with primarily somatic complaints. While patients provide their physicians with multiple clues that there is a functional cause to their complaints, physicians often fail to recognize these. Psychological states, including depression, schizophrenia, hypochondriasis, malingering, conversion reactions, anxiety states, the "identified patient" in a dysfunctional family, and the patient with a "hidden agenda" are examples of this somatization process. Physicians may recognize these problems and avoid needless interventions if they consider these diagnostic possibilities and ask their patients questions that differentiate the various psychological possibilities. PMID:7057147

  1. GISH, AFLP and PCR-RFLP analysis of an intergeneric somatic hybrid combining Goutou sour orange and Poncirus trifoliata.

    PubMed

    Fu, C H; Chen, C L; Guo, W W; Deng, X X

    2004-11-01

    Intergeneric somatic hybrids combining Goutou sour orange (Citrus aurantium L.) with trifoliate orange Poncirus trifoliata (L.) Raf] were produced by electrofusion and their genetic inheritance analyzed by amplified fragment length polymorphism (AFLP), genomic in situ hybridization (GISH), and PCR-restriction fragment length polymorphism (PCR-RFLP). Sixteen mini-calluses were obtained after 20 days of culture; they all developed into embryoids on EME500 medium. Following several subcultures on shoot induction medium for a total culture period of 6 months, shoots regenerated. The plants grew vigorously with a well-developed root system and exhibited the trifoliate leaf character of P. trifoliata. Ploidy analysis verified that all of the regenerates were tetraploids (2 n=4 x=36) as expected. GISH analysis confirmed that 18 chromosomes came from trifoliate orange and the remaining 18 from Goutou sour orange, as with most symmetric somatic hybrid plants; moreover, chromosome translocations were also observed in one plant. AFLP analysis of 16 regenerates and their fusion parents indicated that all of the somatic hybrids except one were genetically uniform. Analysis of the somatic hybrid cytoplasmic genomes with universal primers revealed that their chloroplast DNA (cpDNA) banding patterns were identical to those of the mesophyll parent trifoliate orange, while their mitochondria (mt) genomes were of the callus parent sour orange. The potential of GISH in Citrus somatic hybrid analysis is discussed. PMID:15252694

  2. Expression of TMEM16 paralogs during murine embryogenesis.

    PubMed

    Rock, Jason R; Harfe, Brian D

    2008-09-01

    The TMEM16 protein family has recently been identified through several different experimental strategies including bioinformatic and microarray-based approaches. In mice and humans, there exist 10 paralogs with each containing eight putative transmembrane domains and a conserved C-terminal domain of unknown function. Mutation of at least one member of this family is associated with a human disorder, and several members of this gene family are overexpressed in different types of cancer. Despite their apparent relevance to normal development and disease, little is known about the expression of TMEM16 paralogs during embryonic development. Here, we provide a phylogenetic analysis of mouse and human TMEM16 paralogs and report the expression of Tmem16a, Tmem16b, Tmem16c, Tmem16f, Tmem16h, Tmem16j, and Tmem16k during murine embryogenesis with an emphasis on the respiratory, digestive, skeletal, and integumentary systems. These data should encourage investigations into the functions of TMEM16 paralogs in vertebrate development. PMID:18729231

  3. Early embryogenesis of the pinewood nematode Bursaphelenchus xylophilus.

    PubMed

    Hasegawa, Koichi; Futai, Kazuyoshi; Miwa, Satsuki; Miwa, Johji

    2004-04-01

    The early embryogenesis and cell lineage of the pinewood nematode Bursaphelenchus xylophilus was followed from a single-cell zygote to a 46-cell embryo under Nomarski optics, and elongation of the microtubules was studied by immunostaining. As a B. xylophilus oocyte matures, it passes through a passage connecting the oviduct with the quadricolumella, the distal part of the uterus, and reaches the quadricolumella where it stays for a few minutes and is fertilized. After fertilization, the germinal vesicle disappears, an eggshell is formed, and the male and female pronuclei appear. The pronuclei move toward each other and fuse at the center of the egg. Around this time, the microtubule-organizing center appears. The presumptive region of sperm entry into the oocyte becomes the future anterior portion of the embryo. This anterior-posterior axis determination is opposite to that of Caenorhabditis elegans, where the sperm entry site becomes the posterior portion of the embryo. The optimal growth temperatures of these two nematodes also differ in that temperatures of about 30 degrees C afford the fastest growth rate and highest hatching frequency in B. xylophilus. Otherwise, the lineage resembles that of C. elegans with respect to timing, positioning and the axis orientation of each cell division. PMID:15066194

  4. Expression of evolutionarily conserved eye specification genes during Drosophila embryogenesis

    PubMed Central

    Kumar, Justin P.; Moses, Kevin

    2009-01-01

    Eye specification in Drosophila is thought be controlled by a set of seven nuclear factors that includes the Pax6 homolog, Eyeless. This group of genes is conserved throughout evolution and has been repeatedly recruited for eye specification. Several of these genes are expressed within the developing eyes of vertebrates and mutations in several mouse and human orthologs are the underlying causes of retinal disease syndromes. Ectopic expression in Drosophila of any one of these genes is capable of inducing retinal development, while loss-of-function mutations delete the developing eye. These nuclear factors comprise a complex regulatory network and it is thought that their combined activities are required for the formation of the eye. We examined the expression patterns of four eye specification genes, eyeless (ey), sine oculis (so), eyes absent (eya), and dachshund (dac) throughout all time points of embryogenesis and show that only eyeless is expressed within the embryonic eye anlagen. This is consistent with a recently proposed model in which the eye primordium acquires its competence to become retinal tissue over several time points of development. We also compare the expression of Ey with that of a putative antennal specifying gene Distal-less (Dll). The expression patterns described here are quite intriguing and raise the possibility that these genes have even earlier and wide ranging roles in establishing the head and visual field. PMID:11685574

  5. ER71 directs mesodermal fate decisions during embryogenesis

    PubMed Central

    Rasmussen, Tara L.; Kweon, Junghun; Diekmann, Mackenzie A.; Belema-Bedada, Fikru; Song, Qingfeng; Bowlin, Kathy; Shi, Xiaozhong; Ferdous, Anwarul; Li, Tongbin; Kyba, Michael; Metzger, Joseph M.; Koyano-Nakagawa, Naoko; Garry, Daniel J.

    2011-01-01

    Er71 mutant embryos are nonviable and lack hematopoietic and endothelial lineages. To further define the functional role for ER71 in cell lineage decisions, we generated genetically modified mouse models. We engineered an Er71-EYFP transgenic mouse model by fusing the 3.9 kb Er71 promoter to the EYFP reporter gene. Using FACS and transcriptional profiling, we examined the EYFP+ population of cells in Er71 mutant and wild-type littermates. In the absence of ER71, we observed an increase in the number of EYFP-expressing cells, increased expression of the cardiac molecular program and decreased expression of the hemato-endothelial program, as compared with wild-type littermate controls. We also generated a novel Er71-Cre transgenic mouse model using the same 3.9 kb Er71 promoter. Genetic fate-mapping studies revealed that the ER71-expressing cells give rise to the hematopoietic and endothelial lineages in the wild-type background. In the absence of ER71, these cell populations contributed to alternative mesodermal lineages, including the cardiac lineage. To extend these analyses, we used an inducible embryonic stem/embryoid body system and observed that ER71 overexpression repressed cardiogenesis. Together, these studies identify ER71 as a critical regulator of mesodermal fate decisions that acts to specify the hematopoietic and endothelial lineages at the expense of cardiac lineages. This enhances our understanding of the mechanisms that govern mesodermal fate decisions early during embryogenesis. PMID:21989919

  6. Modeling cell-cycle synchronization during embryogenesis in Xenopus laevis

    NASA Astrophysics Data System (ADS)

    McIsaac, R. Scott; Huang, K. C.; Sengupta, Anirvan; Wingreen, Ned

    2010-03-01

    A widely conserved aspect of embryogenesis is the ability to synchronize nuclear divisions post-fertilization. How is synchronization achieved? Given a typical protein diffusion constant of 10 ?m^2sec, and an embryo length of 1mm, it would take diffusion many hours to propagate a signal across the embryo. Therefore, synchrony cannot be attained by diffusion alone. We hypothesize that known autocatalytic reactions of cell-cycle components make the embryo an ``active medium'' in which waves propagate much faster than diffusion, enforcing synchrony. We report on robust spatial synchronization of components of the core cell cycle circuit based on a mathematical model previously determined by in vitro experiments. In vivo, synchronized divisions are preceded by a rapid calcium wave that sweeps across the embryo. Experimental evidence supports the hypothesis that increases in transient calcium levels lead to derepression of a negative feedback loop, allowing cell divisions to start. Preliminary results indicate a novel relationship between the speed of the initial calcium wave and the ability to achieve synchronous cell divisions.

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

    NASA Technical Reports Server (NTRS)

    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.

  8. The ?-Tocopherol Transfer Protein Is Essential for Vertebrate Embryogenesis

    PubMed Central

    Miller, Galen W.; Ulatowski, Lynn; Labut, Edwin M.; Lebold, Katie M.; Manor, Danny; Atkinson, Jeffrey; Barton, Carrie L.; Tanguay, Robert L.; Traber, Maret G.

    2012-01-01

    The hepatic ?-tocopherol transfer protein (TTP) is required for optimal ?-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 ?-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. PMID:23077608

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

    NASA Astrophysics Data System (ADS)

    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

  10. Structural analysis of embryogenesis of Leiarius marmoratus (Siluriformes: Pimelodidae).

    PubMed

    Oliveira-Almeida, Isângela Rodrigues; Buzollo, Hellen; Costa, Raphael da Silva; Veríssimo-Silveira, Rosicleire; Porto-Foresti, Fábio; Ninhaus-Silveira, Alexandre

    2015-10-01

    Embryological studies in fish species are useful to the understanding of their biology and systematics. The available biological data in Leiarius marmoratus are scarce and additional information about its reproductive biology is needed, mainly because this species has been commercially exploited and used in production of hybrid lineages. In order to evaluate the temporal-morphological embryonic modifications in L. marmoratus, samples of nearly 200 embryos were collected at random at different stages of development, starting from fecundation (time zero). Embryos were fixed in modified Karnovsk's solution and 2.5% glutaraldehyde, processed and analysed under optic and electron microscopy. The incubation period of L. marmoratus was equal to 14.42 h at a mean temperature of 28.3 ± 0.07°C. The following stages of embryonic development were established: zygote, cleavage, gastrula, organogenesis and hatching. These stages were divided into phases, as follows: cleavage - phases of 2, 4, 8, 16, 32 and 64 cells and morula; gastrula - phases of 25, 50, 75 and 90% of epiboly and blastopore closure; and organogenesis - neurula, segmentation and pre-larval phases. The embryogenesis of L. marmoratus was typical of neotropical teleosteans, with peculiarities in species development. PMID:25213196

  11. An optimized procedure for plant recovery from somatic embryos significantly facilitates the genetic improvement of Vitis

    PubMed Central

    Li, Zhijian T; Kim, Kyung-Hee; Dhekney, Sadanand A; Jasinski, Jonathan R; Creech, Matthew R; Gray, Dennis J

    2014-01-01

    Plant regeneration from grapevine (Vitis spp.) via somatic embryogenesis typically is poor. Recovery of plants from Vitis rotundifolia Michx. (muscadine grape) is particularly problematic due to extremely low efficiency, including extended culture durations required for embryo–plant conversion. Poor plant recovery is an obstacle to the selection of improved genetically modified lines. Somatic embryos (SEs) of V. rotundifolia cultivar Delicious (Del-HS) and Vitis vinifera L cultivar Thompson Seedless (TS) were used to identify culture media and conditions that promoted embryo differentiation and plant conversion; this resulted in a two-step culture system. In comparative culture experiments, C2D medium containing 6% sucrose was the most effective, among four distinct formulae tested, for inducing precocious SE germination and cell differentiation. This medium, further supplemented with 4?µM 6-benzylaminopurine (C2D4B), was subsequently determined to enhance post-germinative growth of SE. MS medium supplemented with 0.5?µM 1-naphthaleneacetic acid (MSN) was then utilized to stimulate root and shoot growth of germinated SE. An average of 35% and 80% ‘Del-HS’ and ‘TS’ SE, respectively, developed into plants. All plants developed robust root and shoot systems and exhibited excellent survival following transfer to soil. Over 150 plants of ‘Del-HS’ were regenerated and established within 2.5?months, which is a dramatic reduction from the 6- to 12-month time period previously required. Similarly, 88 ‘TS’ plant lines were obtained within the same time period. Subsequently, seven out of eight Vitis cultivars exhibited significantly increased plant conversion percentages, demonstrating broad application of the two-step culture system to produce the large numbers of independent plant lines needed for selection of desired traits. PMID:26504540

  12. [Somatization, migration and culture: common assumptions and alternative strategies].

    PubMed

    Dominicé, Dao Melissa

    2012-06-27

    This article wishes to deconstruct the stereotype of the "somatizing migrant" by reexamining the process of somatization in a cultural perspective and by pointing out the factors that may jeopardize the therapeutic relationship with a migrant patient. It offers suggestions to broaden the clinician's perspective of his patient, and argues for multiple interpretations of the somatization process. PMID:22872941

  13. Treating Somatic Fixation: A Biopsychosocial Approach

    PubMed Central

    McDaniel, Susan H.; Campbell, Thomas; Seaburn, David

    1991-01-01

    Somatic fixation occurs when the patient or physician focuses exclusively on the biomedical aspects of a complex illness. Individual, family, and cultural factors promote the expression of emotional experience through physical symptoms. The physician or treatment team establishes a collaborative relationship with the patient and family, integrating biomedical and psychosocial evaluations and respecting the patient's defenses. PMID:21228995

  14. Somatic Symptoms in Traumatized Children and Adolescents

    ERIC Educational Resources Information Center

    Kugler, Brittany B.; Bloom, Marlene; Kaercher, Lauren B.; Truax, Tatyana V.; Storch, Eric A.

    2012-01-01

    Childhood exposure to trauma has been associated with increased rates of somatic symptoms (SS), which may contribute to diminished daily functioning. One hundred and sixty-one children residing at a residential treatment home who had experienced neglect and/or abuse were administered the Trauma Symptom Checklist for Children (TSCC), the…

  15. Attribution of somatic symptoms in hypochondriasis.

    PubMed

    Neng, Julia M B; Weck, Florian

    2015-01-01

    The misinterpretation of bodily symptoms as an indicator of a serious illness is a key feature of the criteria and the cognitive-behavioural models of hypochondriasis. Previous research suggests that individuals suffering from health anxiety endorse attributions of physical disease, whereas persons with elevated general anxiety have the tendency to attribute psychological causes to their symptoms. However, whether a somatic attribution style is specific to patients with hypochondriasis, as opposed to those with anxiety disorders, has not yet been investigated and is therefore part of the present study. Fifty patients with hypochondriasis, 50 patients with a primary anxiety disorder and 50 healthy participants were presented with nine common bodily sensations and had to spontaneously attribute possible causes to the symptoms. Patients with hypochondriasis differed from patients with anxiety disorders and healthy controls in giving significantly fewer normalizing explanations, but attributing more often in terms of moderate or serious diseases. Patients with anxiety disorders also made significantly fewer normalizing attributions and more somatic attributions to a severe illness than healthy controls. There were no differences between the groups in the frequency of psychological attributions and somatic attributions concerning mild diseases. The present study demonstrates that hypochondriasis is associated with a disorder-specific attribution style connecting somatic symptoms primarily with moderate and serious diseases. By contrast, normalizing attributions are largely omitted from consideration by patients with hypochondriasis. The findings conform with the cognitive conception of hypochondriasis and support the strategy of modifying symptom attributions, as practiced in cognitive-behavioural therapy. PMID:24123559

  16. RBE for late somatic effects in mice irradiated with 60 MeV protons relative to X-rays.

    NASA Technical Reports Server (NTRS)

    Darden, E. B., Jr.; Clapp, N. K.; Bender, R. S.; Jernigan, M. C.; Upton, A. C.

    1971-01-01

    Investigation of the relative biological effectiveness of energetic protons for the induction of somatic effects in a mammal (mice) following whole body irradiation. The proton energy used approximates the mean energy for proton spectra accompanying solar events. The effects on longevity and the incidence of major neoplastic diseases are summarized. The results obtained suggest that medium energy proton irradiation is no more effective, and on the whole, probably less effective, than conventional X radiation for the induction of late radiation effects in the mouse.

  17. Effect of ovary induction on bread wheat anther culture: ovary genotype and developmental stage, and candidate gene association

    PubMed Central

    Castillo, Ana M.; Sánchez-Díaz, Rosa A.; Vallés, María P.

    2015-01-01

    Ovary pre-conditioned medium and ovary co-culture increased the efficiency of green doubled haploid plant production in bread wheat anther culture. The positive effect of this medium led to a 6- and 11-fold increase in the numbers of embryos and green plants, respectively, having a greater effect on a medium-low responding cultivar. Ovary genotype and developmental stage significantly affected microspore embryogenesis. By the use of Caramba ovaries it was possible to reach a 2-fold increase in the number of embryos and green plants, and to decrease the rate of albinism. Mature ovaries from flowers containing microspores at a late binucleate stage raised the number of embryos and green plants by 25–46% as compared to immature ovaries (excised from flowers with microspores at a mid-late uninucleate stage). The highest numbers of embryos and green plants were produced when using mature Caramba ovaries. Ovaries from Galeón, Tigre, and Kilopondio cultivars successfully induced microspore embryogenesis at the same rate as Caramba ovaries. Moreover, Tigre ovaries raised the percentage of spontaneous chromosome doubling up to 71%. Attempts were made to identify molecular mechanisms associated to the inductive effect of the ovaries on microspore embryogenesis. The genes TAA1b, FLA26, and WALI6 associated to wheat microspore embryogenesis, the CGL1 gene involved in glycan biosynthesis or degradation, and the FER gene involved in the ovary signaling process were expressed and/or induced at different rates during ovary culture. The expression pattern of FLA26 and FER could be related to the differences between genotypes and developmental stages in the inductive effect of the ovary. Our results open opportunities for new approaches to increase bread wheat doubled haploid production by anther culture, and to identify the functional components of the ovary inductive effect on microspore embryogenesis. PMID:26150821

  18. Effect of ovary induction on bread wheat anther culture: ovary genotype and developmental stage, and candidate gene association.

    PubMed

    Castillo, Ana M; Sánchez-Díaz, Rosa A; Vallés, María P

    2015-01-01

    Ovary pre-conditioned medium and ovary co-culture increased the efficiency of green doubled haploid plant production in bread wheat anther culture. The positive effect of this medium led to a 6- and 11-fold increase in the numbers of embryos and green plants, respectively, having a greater effect on a medium-low responding cultivar. Ovary genotype and developmental stage significantly affected microspore embryogenesis. By the use of Caramba ovaries it was possible to reach a 2-fold increase in the number of embryos and green plants, and to decrease the rate of albinism. Mature ovaries from flowers containing microspores at a late binucleate stage raised the number of embryos and green plants by 25-46% as compared to immature ovaries (excised from flowers with microspores at a mid-late uninucleate stage). The highest numbers of embryos and green plants were produced when using mature Caramba ovaries. Ovaries from Galeón, Tigre, and Kilopondio cultivars successfully induced microspore embryogenesis at the same rate as Caramba ovaries. Moreover, Tigre ovaries raised the percentage of spontaneous chromosome doubling up to 71%. Attempts were made to identify molecular mechanisms associated to the inductive effect of the ovaries on microspore embryogenesis. The genes TAA1b, FLA26, and WALI6 associated to wheat microspore embryogenesis, the CGL1 gene involved in glycan biosynthesis or degradation, and the FER gene involved in the ovary signaling process were expressed and/or induced at different rates during ovary culture. The expression pattern of FLA26 and FER could be related to the differences between genotypes and developmental stages in the inductive effect of the ovary. Our results open opportunities for new approaches to increase bread wheat doubled haploid production by anther culture, and to identify the functional components of the ovary inductive effect on microspore embryogenesis. PMID:26150821

  19. Lipidomics: The Function of Vital Lipids in Embryogenesis Preventing Autism Spectrum Disorders, Treating Sterile Inflammatory Diatheses with a Lymphopoietic Central Nervous System Component

    PubMed Central

    Tallberg, Thomas; Dabek, Jan; Hallamaa, Raija; Atroshi, Faik

    2011-01-01

    The central role performed by billions of vital central nervous system (CNS) lipids “lipidomics” in medical physiology is usually overlooked. A metabolic deficiency embracing these vital lipids can form the aetiology for a variety of diseases. CNS lipids regulate embryogenesis, cell induction, mental balance by preventing autism spectrum disorders, depression, burn-out syndromes like posttraumatic stress disease PTSD, by guarding normal immunity, treating sterile inflammatory diatheses with a titanium containing lymphopoietic CNS lipid component. The propaganda driving for unphysiological fat-free diets is dangerous and can cause serious health problems for a whole generation. This article presents a broad list of various mental and motor bodily functions of which the healthy function depends on these vital CNS lipids. A rigorous fat-free diet can provoke these metabolic lipid deficiencies but they can fortunately be compensated by dietary supplementation, but not by pharmacologic treatment. PMID:21490796

  20. Induction machine

    DOEpatents

    Owen, Whitney H. (Ogden, UT)

    1980-01-01

    A polyphase rotary induction machine for use as a motor or generator utilizing a single rotor assembly having two series connected sets of rotor windings, a first stator winding disposed around the first rotor winding and means for controlling the current induced in one set of the rotor windings compared to the current induced in the other set of the rotor windings. The rotor windings may be wound rotor windings or squirrel cage windings.

  1. Chromatin dynamics in pollen mother cells underpin a common scenario at the somatic-to-reproductive fate transition of both the male and female lineages in Arabidopsis

    PubMed Central

    She, Wenjing; Baroux, Célia

    2015-01-01

    Unlike animals, where the germline is established early during embryogenesis, plants set aside their reproductive lineage late in development in dedicated floral organs. The specification of pollen mother cells (PMC) committed to meiosis takes place in the sporogenous tissue in anther locules and marks the somatic-to-reproductive cell fate transition toward the male reproductive lineage. Here we show that Arabidopsis PMC differentiation is accompanied by large-scale changes in chromatin organization. This is characterized by significant increase in nuclear volume, chromatin decondensation, reduction in heterochromatin, eviction of linker histones and the H2AZ histone variant. These structural alterations are accompanied by dramatic, quantitative changes in histone modifications levels compared to that of surrounding somatic cells that do not share a sporogenic fate. All these changes are highly reminiscent of those we have formerly described in female megaspore mother cells (MMC). This indicates that chromatin reprogramming is a common underlying scenario in the somatic-to-reproductive cell fate transition in both male and female lineages. PMID:25972887

  2. Chromatin dynamics in pollen mother cells underpin a common scenario at the somatic-to-reproductive fate transition of both the male and female lineages in Arabidopsis.

    PubMed

    She, Wenjing; Baroux, Célia

    2015-01-01

    Unlike animals, where the germline is established early during embryogenesis, plants set aside their reproductive lineage late in development in dedicated floral organs. The specification of pollen mother cells (PMC) committed to meiosis takes place in the sporogenous tissue in anther locules and marks the somatic-to-reproductive cell fate transition toward the male reproductive lineage. Here we show that Arabidopsis PMC differentiation is accompanied by large-scale changes in chromatin organization. This is characterized by significant increase in nuclear volume, chromatin decondensation, reduction in heterochromatin, eviction of linker histones and the H2AZ histone variant. These structural alterations are accompanied by dramatic, quantitative changes in histone modifications levels compared to that of surrounding somatic cells that do not share a sporogenic fate. All these changes are highly reminiscent of those we have formerly described in female megaspore mother cells (MMC). This indicates that chromatin reprogramming is a common underlying scenario in the somatic-to-reproductive cell fate transition in both male and female lineages. PMID:25972887

  3. LEAPdb: a database for the late embryogenesis abundant proteins

    PubMed Central

    2010-01-01

    Background Late Embryogenesis Abundant Proteins database (LEAPdb) contains resource regarding LEAP from plants and other organisms. Although LEAP are grouped into several families, there is no general consensus on their definition and on their classification. They are associated with abiotic stress tolerance, but their actual function at the molecular level is still enigmatic. The scarcity of 3-D structures for LEAP remains a handicap for their structure-function relationships analysis. Finally, the growing body of published data about LEAP represents a great amount of information that needs to be compiled, organized and classified. Results LEAPdb gathers data about 8 LEAP sub-families defined by the PFAM, the Conserved Domain and the InterPro databases. Among its functionalities, LEAPdb provides a browse interface for retrieving information on the whole database. A search interface using various criteria such as sophisticated text expression, amino acids motifs and other useful parameters allows the retrieving of refined subset of entries. LEAPdb also offers sequence similarity search. Information is displayed in re-ordering tables facilitating the analysis of data. LEAP sequences can be downloaded in three formats. Finally, the user can submit his sequence(s). LEAPdb has been conceived as a user-friendly web-based database with multiple functions to search and describe the different LEAP families. It will likely be helpful for computational analyses of their structure - function relationships. Conclusions LEAPdb contains 769 non-redundant and curated entries, from 196 organisms. All LEAP sequences are full-length. LEAPdb is publicly available at http://forge.info.univ-angers.fr/~gh/Leadb/index.php. PMID:20359361

  4. Live-cell imaging and optical manipulation of Arabidopsis early embryogenesis.

    PubMed

    Gooh, Keita; Ueda, Minako; Aruga, Kana; Park, Jongho; Arata, Hideyuki; Higashiyama, Tetsuya; Kurihara, Daisuke

    2015-07-27

    Intercellular communications are essential for cell proliferation and differentiation during plant embryogenesis. However, analysis of intercellular communications in living material in real time is difficult owing to the restricted accessibility of the embryo within the flower. We established a live-embryo imaging system to visualize cell division and cell fate specification in Arabidopsis thaliana from zygote division in real time. We generated a cell-division lineage tree for early embryogenesis in Arabidopsis. Lineage analysis showed that both the direction and time course of cell division between sister cells differed along the apical-basal or radial axes. Using the Arabidopsis kpl mutant, in which single-fertilization events are frequent, we showed that endosperm development is not required for pattern formation during early embryogenesis. Optical manipulation demonstrated that damage to the embryo initial cell induces cell fate conversion of the suspensor cell to compensate for the disrupted embryo initial cell even after cell fate is specified. PMID:26166301

  5. Somatic Cell Reprogramming into Cardiovascular Lineages

    PubMed Central

    Chen, Jenny X.; Plonowska, Karolina; Wu, Sean M.

    2015-01-01

    Ischemic cardiac disease is the leading cause of death in the developed world. The inability of the adult mammalian heart to adequately repair itself has motivated stem cell researchers to explore various strategies to regenerate cardiomyocytes after myocardial infarction. Over the past century, progressive gains in our knowledge about the cellular mechanisms governing fate determination have led to recent advances in cellular reprogramming. The identification of specific factors capable of inducing pluripotent phenotype in somatic cells as well as factors that can directly reprogram somatic cells into cardiomyocytes suggests the potential for these approaches to translate into clinical therapies in the future. While conceptually appealing, the field of cell lineage reprogramming is in its infancy and further research will be needed to improve the efficiency of the reprogramming process and the fidelity of the reprogrammed cells to their in vivo counterpart. PMID:24764131

  6. Emerging patterns of somatic mutations in cancer

    PubMed Central

    Watson, Ian R.; Takahashi, Koichi; Futreal, P. Andrew; Chin, Lynda

    2014-01-01

    The advance in technological tools for massively parallel, high-throughput sequencing of DNA has enabled the comprehensive characterization of somatic mutations in large number of tumor samples. Here, we review recent cancer genomic studies that have assembled emerging views of the landscapes of somatic mutations through deep sequencing analyses of the coding exomes and whole genomes in various cancer types. We discuss the comparative genomics of different cancers, including mutation rates, spectrums, and roles of environmental insults that influence these processes. We highlight the developing statistical approaches used to identify significantly mutated genes, and discuss the emerging biological and clinical insights from such analyses as well as the challenges ahead translating these genomic data into clinical impacts. PMID:24022702

  7. Maternal brain death and somatic support.

    PubMed

    Farragher, Rachel A; Laffey, John G

    2005-01-01

    Brain death is a concept used in situations in which life-support equipment obscures the conventional cardiopulmonary criteria of death, and it is legally recognized in most countries worldwide. Brain death during pregnancy is an occasional and tragic occurrence. The mother and fetus are two distinct organisms, and the death of the mother mandates consideration of the well-being of the fetus. Where maternal brain death occurs after the onset of fetal viability, the benefits of prolonging the pregnancy to allow further fetal maturation must be weighed against the risks of continued time in utero, and preparations must be made to facilitate urgent cesarean section and fetal resuscitation at short notice. Where the fetus is nonviable, one must consider whether continuation of maternal organ supportive measures in an attempt to attain fetal viability is appropriate, or whether it constitutes futile care. Although the gestational age of the fetus is central to resolving this issue, there is no clear upper physiological limit to the prolongation of somatic function after brain death. Furthermore, medical experience regarding prolonged somatic support is limited and can be considered experimental therapy. This article explores these issues by considering the concept of brain death and how it relates to somatic death. The current limits of fetal viability are then discussed. The complex ethical issues and the important variations in the legal context worldwide are considered. Finally, the likelihood of successfully sustaining maternal somatic function for prolonged periods and the medical and obstetric issues that are likely to arise are examined. PMID:16174876

  8. Somatic SETBP1 mutations in myeloid malignancies.

    PubMed

    Makishima, Hideki; Yoshida, Kenichi; Nguyen, Nhu; Przychodzen, Bartlomiej; Sanada, Masashi; Okuno, Yusuke; Ng, Kwok Peng; Gudmundsson, Kristbjorn O; Vishwakarma, Bandana A; Jerez, Andres; Gomez-Segui, Ines; Takahashi, Mariko; Shiraishi, Yuichi; Nagata, Yasunobu; Guinta, Kathryn; Mori, Hiraku; Sekeres, Mikkael A; Chiba, Kenichi; Tanaka, Hiroko; Muramatsu, Hideki; Sakaguchi, Hirotoshi; Paquette, Ronald L; McDevitt, Michael A; Kojima, Seiji; Saunthararajah, Yogen; Miyano, Satoru; Shih, Lee-Yung; Du, Yang; Ogawa, Seishi; Maciejewski, Jaroslaw P

    2013-08-01

    Here we report whole-exome sequencing of individuals with various myeloid malignancies and identify recurrent somatic mutations in SETBP1, consistent with a recent report on atypical chronic myeloid leukemia (aCML). Closely positioned somatic SETBP1 mutations encoding changes in Asp868, Ser869, Gly870, Ile871 and Asp880, which match germline mutations in Schinzel-Giedion syndrome (SGS), were detected in 17% of secondary acute myeloid leukemias (sAML) and 15% of chronic myelomonocytic leukemia (CMML) cases. These results from deep sequencing demonstrate a higher mutational detection rate than reported with conventional sequencing methodology. Mutant cases were associated with advanced age and monosomy 7/deletion 7q (-7/del(7q)) constituting poor prognostic factors. Analysis of serially collected samples indicated that SETBP1 mutations were acquired during leukemic evolution. Transduction with mutant Setbp1 led to the immortalization of mouse myeloid progenitors that showed enhanced proliferative capacity compared to cells transduced with wild-type Setbp1. Somatic mutations of SETBP1 seem to cause gain of function, are associated with myeloid leukemic transformation and convey poor prognosis in myelodysplastic syndromes (MDS) and CMML. PMID:23832012

  9. Somatic Cell Nuclear Transfer in the Mouse

    NASA Astrophysics Data System (ADS)

    Kishigami, Satoshi; Wakayama, Teruhiko

    Somatic cell nuclear transfer (SCNT) has become a unique and powerful tool for epigenetic reprogramming research and gene manipulation in animals since “Dolly,” the first animal cloned from an adult cell was reported in 1997. Although the success rates of somatic cloning have been inefficient and the mechanism of reprogramming is still largely unknown, this technique has been proven to work in more than 10 mammalian species. Among them, the mouse provides the best model for both basic and applied research of somatic cloning because of its abounding genetic resources, rapid sexual maturity and propagation, minimal requirements for housing, etc. This chapter describes a basic protocol for mouse cloning using cumulus cells, the most popular cell type for NT, in which donor nuclei are directly injected into the oocyte using a piezo-actuated micromanipulator. In particular, we focus on a new, more efficient mouse cloning protocol using trichostatin A (TSA), a histone deacetylase (HDAC) inhibitor, which increases both in vitro and in vivo developmental rates from twofold to fivefold. This new method including TSA will be helpful to establish mouse cloning in many laboratories.

  10. Cloned mice derived from somatic cell nuclei.

    PubMed

    Hosaka, K; Ohi, S; Ando, A; Kobayashi, M; Sato, K

    2000-12-01

    In 1997, a cloned sheep "Dolly" was produced by nuclear transfer of somatic cell. The first birth of cloned mice derived from some somatic cells were succeeded in 1998. At present, it is shown that somatic cells, cumulus cells, fibroblasts and Sertoli cells can be used to the study of cloned animal as nuclear donor. In this study investigation was designed to compare with efficiency on the production of cloned embryos by using the microinjection and the electrofusion methods for nuclear transfer. Oocyte enucleation was performed with a micromanipulator. The oocyte was held by holding pipette, and was enucleated using a beveled pipette. Microinjection method: Cell's nucleus injection was carried out by piezo-micromanipulator. Cytochalasin B treated cumulus cell was aspirated into a injection pipette, and was broken its plasma membrane using the injection pipette. Then, the cumulus cell was injected into the enucleated ooplasm directly. Electrofusion method: The cell was aspirated into a beveled pipette, and then an aspirated cell was inserted into perivitelline space. Then, the pair of enucleated oocyte and cell was fused using electrical cell fusion apparatus. The reconstituted embryos were activated after nuclear transfer using St2+. Reconstituted embryos had been produced by the microinjection showed the embryonic development to over 8-cell stages. But, the rate of fragmentation of reconstituted embryos by the microinjection showed a little high rate in comparison with the electrofusion. When some reconstituted embryos by the microinjection were transplanted to pseudopregnant females' oviduct, 9 fetuses were observed at 14 days post coitum. PMID:11329940

  11. The ?-cyclin expression at early stages of embryogenesis of Brassica rapa L. under clinorotation

    NASA Astrophysics Data System (ADS)

    Artemenko, O. A.; Popova, A. F.

    We present some results of comparison studying of Brassica embryo development and the ?-cyclin genes expression under slow horizontal clinorotation and in the laboratory control. Some backlog of the ?1-cyclin genes expression at early stages of embryogenesis under clinorotation was revealed in comparison with the laboratory control. The similar level of the ?3-cyclin expression at all stages of embryo formation (from one to nine days) in both variants is shown. Some delays in the rate of Brassica rapa embryo development under clinorotation in comparison with the laboratory control can be a result of decrease of a level and some backlog of the ?1-cyclin expression at early stages of embryogenesis.

  12. Regional specification during embryogenesis in the inarticulate brachiopod Discinisca.

    PubMed

    Freeman, G

    1999-05-15

    The process of embryogenesis is described for the inarticulate brachiopod Discinisca strigata of the family Discinidae. A fate map has been constructed for the early embryo. The animal half of the egg forms the dorsal ectoderm of the apical and mantle lobes. The vegetal half forms mesoderm and endoderm and is the site of gastrulation; it also forms the ectoderm of the ventral regions of the apical and mantle lobes of the larva. The plane of the first cleavage goes through the animal-vegetal axis of the egg along the future plane of bilateral symmetry of the larva. The timing of regional specification in these embryos was examined by isolating animal, vegetal, or lateral regions at different times from the 2-cell stage through gastrulation. Animal halves isolated at the 8-cell and blastula stages formed an epithelial vesicle and did not gastrulate. When these halves were isolated from blastulae they formed the cell types typical of apical and mantle lobes. Vegetal halves isolated at all stages gastrulated and formed a more or less normal larva; the only defect these larvae had was the lack of an apical tuft, which normally forms from cells at the animal pole of the embryo. When lateral isolates were created at all developmental stages, these halves gastrulated. Cuts which separated presumptive anterior and posterior regions generated isolates at the 4-cell and blastula stages that formed essentially normal larvae; however, at the midgastrula stage these halves formed primarily anterior or posterior structures indicating that regional specification had taken place along the anterior-posterior axis. The plane of the first cleavage, which predicts the plane of bilateral symmetry, can be shifted by either changing the cleavage pattern that generates the bilateral 16-cell blastomere configuration or by isolating embryo halves prior to, or during, the 16-cell stage. These results indicate that while the plane of the first cleavage predicts the axis of bilateral symmetry, the axis is not established until the fourth cleavage. The development of Discinisca is compared to development in the inarticulate brachiopod Glottidia of the family Lingulidae and to Phoronis in the phylum Phoronida. PMID:10328924

  13. Family background and sexual abuse associated with somatization.

    PubMed

    Kinzl, J F; Traweger, C; Biebl, W

    1995-01-01

    To help clarify the complex association between negative childhood experiences and somatization, the authors examined the possible relationship between self-reported childhood sexual abuse, dysfunctional family background and several types of somatization in a nonclinical sample. Three anonymous questionnaires were completed by 202 female university students (average age 22 years). The findings confirm that severe or repeated childhood sexual victimization and a familial deficiency syndrome in childhood may be important in the pathogenesis of somatization. PMID:8559957

  14. Human somatic mutation assays as biomarkers of carcinogenesis

    SciTech Connect

    Compton, P.J.E.; Smith, M.T. ); Hooper, K. )

    1991-08-01

    This paper describes four assays that detect somatic gene mutations in humans: the hypoxanthine-guanine phosphoribosyl transferase assay, the glycophorin A assay, the HLA-A assay, and the sickle cell hemoglobin assay. Somatic gene mutations can be considered a biomarker of carcinogenesis, and assays for somatic mutation may assist epidemiologists in studies that attempt to identify factors associated with increased risks of cancer. Practical aspects of the use of these assays are discussed.

  15. Shoot regeneration and embryogenesis in lily shoot tips cryopreserved by droplet vitrification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shoot regeneration and embryogenesis were, for the first time, achieved directly in shoot tips of Lilium Oriental hybrid ‘Siberia’ following cryopreservation by droplet-vitrification. Shoot tips (2 mm in length) including 2-3 leaf primordia were excised from 4-week-old adventitious shoots directly r...

  16. Cytokinin and auxin interaction in root stem-cell specification during early embryogenesis

    E-print Network

    Sheen, Jen

    LETTERS Cytokinin and auxin interaction in root stem-cell specification during early embryogenesis Bruno Mu¨ller1 & Jen Sheen1 Plant stem-cell pools, the source for all organs, are first established regeneration in cultured tissue1 . Auxin has a critical role in root stem-cell specification in zygotic

  17. Noncanonical expression of caudal during early embryogenesis in the pea aphid Acyrthosiphon pisum

    E-print Network

    Wu, Yih-Min

    Noncanonical expression of caudal during early embryogenesis in the pea aphid Acyrthosiphon pisum embryos of the parthenogenetic and viviparous pea aphid Acyrthosiphon pisum, suggesting that the breaking posterior development in the asexual pea aphid, we cloned and analysed the developmental expression

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

    ERIC Educational Resources Information Center

    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…

  19. VERTEBRAL ABNORMALITIES IN JUVENILE INLAND SILVERSIDES, MENIDIA BERYLLINA, EXPOSED TO TERBUFOS DURING EMBRYOGENESIS

    EPA Science Inventory

    Embryos of the inland silverside, Menidia beryllina, were exposed to nominal concentration of 50 ug terbufos 1-1 during the first five days of embryogenesis. ilversides were maintained in clean dilute seawater until 37 days after hatching. adiographs revealed compressed and use v...

  20. Repression of somatic cell fate in the germline.

    PubMed

    Robert, Valérie J; Garvis, Steve; Palladino, Francesca

    2015-10-01

    Germ cells must transmit genetic information across generations, and produce gametes while also maintaining the potential to form all cell types after fertilization. Preventing the activation of somatic programs is, therefore, crucial to the maintenance of germ cell identity. Studies in Caenorhabditis elegans, Drosophila melanogaster, and mouse have revealed both similarities and differences in how somatic gene expression is repressed in germ cells, thereby preventing their conversion into somatic tissues. This review will focus on recent developments in our understanding of how global or gene-specific transcriptional repression, chromatin regulation, and translational repression operate in the germline to maintain germ cell identity and repress somatic differentiation programs. PMID:26043973

  1. Release of somatic embryogenic potential from excised zygotic embryos of carrot and maintenance of proembryonic cultures in hormone-free medium

    NASA Technical Reports Server (NTRS)

    Smith, D. L.; Krikorian, A. D.

    1989-01-01

    Excised zygotic embryos, mericarps ("seeds") and hypocotyls of seedlings of cultivated carrot Daucus carota cv. Scarlet Nantes were evaluated for their ability to generate somatic embryos on a semisolid hormone-free nutrient medium. Neither intact zygotic embryos nor hypocotyls ever produced somatic embryos. However, mericarps and broken zygotic embryos were excellent sources for somatic embryo production (response levels as high as 86%). Somatic embryo formation was highest from cotyledons, but was also observed on isolated hypocotyls and root tips of mature zygotic embryos. On media containing unreduced nitrogen, somatic embryo formation led to the generation of vigorous cultures comprised entirely of somatic embryos at various stages of development which in turn proliferated still other somatic embryos. However, a medium was devised which when 1-5 mM NH4+ was the sole nitrogen source, led only to a proliferation of globular proembryos. Sustained subculturing of these proembryos at 2-3 week intervals enabled establishment of highly uniform cultures in which no further development into more mature stages of embryonic development occurred. These have been maintained, without decline, as morphogenetically competent proembryonic globules for over ten months. A basal medium containing from 1-5 mM NH4+ as the sole nitrogen source appears not to be inductive to somatic proembryo formation. Instead, such a medium is best thought of as permissive to the expression of embryogenically determined cells within zygotic embryos. By excising and breaking or wounding zygotic embryos, constituent cells are probably released from positional or chemical restraints and thus are able to express their innate embryogenic potential. Once a proembryonic culture is established, this medium containing 1-5 mM NH4+ as the sole nitrogen source provides a nonpermissive environment to the development and growth of later embryonic stages, but it does allow the continued formation and multiplication of globular somatic proembryos. The sequence of events leading from excised broken zygotic embryos to the formation of somatic embryos and the maintenance of somatic proembryos are demonstrated by scanning electron microscopy and histological preparations. Germination levels from intact zygotic embryos on media with varying levels and ratios of unreduced vs. reduced inorganic nitrogen were determined as well and provided baseline or control data on the type of response obtained from nonwounded material.

  2. Ancient origin of somatic and visceral neurons

    PubMed Central

    2013-01-01

    Background A key to understanding the evolution of the nervous system on a large phylogenetic scale is the identification of homologous neuronal types. Here, we focus this search on the sensory and motor neurons of bilaterians, exploiting their well-defined molecular signatures in vertebrates. Sensorimotor circuits in vertebrates are of two types: somatic (that sense the environment and respond by shaping bodily motions) and visceral (that sense the interior milieu and respond by regulating vital functions). These circuits differ by a small set of largely dedicated transcriptional determinants: Brn3 is expressed in many somatic sensory neurons, first and second order (among which mechanoreceptors are uniquely marked by the Brn3+/Islet1+/Drgx+ signature), somatic motoneurons uniquely co-express Lhx3/4 and Mnx1, while the vast majority of neurons, sensory and motor, involved in respiration, blood circulation or digestion are molecularly defined by their expression and dependence on the pan-visceral determinant Phox2b. Results We explore the status of the sensorimotor transcriptional code of vertebrates in mollusks, a lophotrochozoa clade that provides a rich repertoire of physiologically identified neurons. In the gastropods Lymnaea stagnalis and Aplysia californica, we show that homologues of Brn3, Drgx, Islet1, Mnx1, Lhx3/4 and Phox2b differentially mark neurons with mechanoreceptive, locomotory and cardiorespiratory functions. Moreover, in the cephalopod Sepia officinalis, we show that Phox2 marks the stellate ganglion (in line with the respiratory — that is, visceral— ancestral role of the mantle, its target organ), while the anterior pedal ganglion, which controls the prehensile and locomotory arms, expresses Mnx. Conclusions Despite considerable divergence in overall neural architecture, a molecular underpinning for the functional allocation of neurons to interactions with the environment or to homeostasis was inherited from the urbilaterian ancestor by contemporary protostomes and deuterostomes. PMID:23631531

  3. Mechanisms and models of somatic cell reprogramming

    PubMed Central

    Buganim, Yosef; Faddah, Dina A.; Jaenisch, Rudolf

    2014-01-01

    Conversion of somatic cells to pluripotency by defined factors is a long and complex process that yields embryonic stem cell-like cells that vary in their developmental potential. To improve the quality of resulting induced pluripotent stem cells (iPSCs), which is important for potential therapeutic applications, and to address fundamental questions about control of cell identity, molecular mechanisms of the reprogramming process must be understood. Here we discuss recent discoveries regarding the role of reprogramming factors in remodeling the genome, including new insights into the function of c-Myc, and describe the different phases, markers and emerging models of reprogramming. PMID:23681063

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

    PubMed

    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 (<24 h) stronger expression of 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, ?-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 pathways and key node proteins allow for further functional analysis and genetic manipulation for both the honey bee embryos and other eusocial insects. PMID:24895377

  5. In-depth Proteomics Characterization of Embryogenesis of the Honey Bee Worker (Apis mellifera ligustica) *

    PubMed Central

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

    2014-01-01

    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 (<24 h) stronger expression of 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, ?-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 pathways and key node proteins allow for further functional analysis and genetic manipulation for both the honey bee embryos and other eusocial insects. PMID:24895377

  6. Arabinogalactan protein profiles and distribution patterns during microspore embryogenesis and pollen development in Brassica napus.

    PubMed

    El-Tantawy, Ahmed-Abdalla; Solís, María-Teresa; Da Costa, Mario L; Coimbra, Silvia; Risueño, María-Carmen; Testillano, Pilar S

    2013-09-01

    Arabinogalactan proteins (AGPs), present in cell walls, plasma membranes and extracellular secretions, are massively glycosylated hydroxyproline-rich proteins that play a key role in several plant developmental processes. After stress treatment, microspores cultured in vitro can reprogramme and change their gametophytic developmental pathways towards embryogenesis, thereby producing embryos which can further give rise to haploid and double haploid plants, important biotechnological tools in plant breeding. Microspore embryogenesis constitutes a convenient system for studying the mechanisms underlying cell reprogramming and embryo formation. In this work, the dynamics of both AGP presence and distribution were studied during pollen development and microspore embryogenesis in Brassica napus, by employing a multidisciplinary approach using monoclonal antibodies for AGPs (LM2, LM6, JIM13, JIM14, MAC207) and analysing the expression pattern of the BnAGP Sta 39-4 gene. Results showed the developmental regulation and defined localization of the studied AGP epitopes during the two microspore developmental pathways, revealing different distribution patterns for AGPs with different antigenic reactivity. AGPs recognized by JIM13, JIM14 and MAC207 antibodies were related to pollen maturation, whereas AGPs labelled by LM2 and LM6 were associated with embryo development. Interestingly, the AGPs labelled by JIM13 and JIM14 were induced with the change of microspore fate. Increases in the expression of the Sta 39-4 gene, JIM13 and JIM14 epitopes found specifically in 2-4 cell stage embryo cell walls, suggested that AGPs are early molecular markers of microspore embryogenesis. Later, LM2 and LM6 antigens increased progressively with embryo development and localized on cell walls and cytoplasmic spots, suggesting an active production and secretion of AGPs during in vitro embryo formation. These results give new insights into the involvement of AGPs as potential regulating/signalling molecules in microspore reprogramming and embryogenesis. PMID:23729197

  7. Reprogramming of human somatic cells by bacteria.

    PubMed

    Ito, Naofumi; Ohta, Kunimasa

    2015-05-01

    In general, it had been believed that the cell fate restriction of terminally differentiated somatic cells was irreversible. In 1952, somatic cell nuclear transfer (SCNT) was introduced to study early embryonic development in frogs. So far, various mammalian species have been successfully cloned using the SCNT technique, though its efficiency is very low. Embryonic stem (ES) cells were the first pluripotent cells to be isolated from an embryo and have a powerful potential to differentiate into more than 260 types of cells. The generation of induced pluripotent stem (iPS) cells was a breakthrough in stem cell research, and the use of these iPS cells has solved problems such as low efficiency and cell fate restriction. These cells have since been used for clinical application, disease investigation, and drug selection. As it is widely accepted that the endosymbiosis of Archaea into eukaryotic ancestors resulted in the generation of eukaryotic cells, we examined whether bacterial infection could alter host cell fate. We previously showed that when human dermal fibroblast (HDF) cells were incorporated with lactic acid bacteria (LAB), the LAB-incorporated HDF cells formed clusters and expressed a subset of common pluripotent markers. Moreover, LAB-incorporated cell clusters could differentiate into cells derived from each of the three germinal layers both in vivo and in vitro, indicating successful reprogramming of host HDF cells by LAB. In the current review, we introduce the existing examples of cellular reprogramming by bacteria and discuss their nuclear reprogramming mechanisms. PMID:25866152

  8. The linear process of somatic evolution Martin A. Nowak*

    E-print Network

    . This design can slow down the rate of somatic evolution dramatically and therefore delay the onset of cancerThe linear process of somatic evolution Martin A. Nowak* , Franziska Michor*, and Yoh Iwasa Cancer Center at Johns Hopkins, Baltimore, MD, and approved October 16, 2003 (received for review August

  9. Somatics in the Dance Studio: Embodying Feminist/Democratic Pedagogy

    ERIC Educational Resources Information Center

    Burnidge, Anne

    2012-01-01

    Since the 1970s, somatics have increasingly become a part of the dance training landscape. Although the psychophysical benefits seem sufficient in themselves to warrant inclusion in dance, this article explores another possible outcome of embracing somatic pedagogical principles, a change that affects not "what" is taught in a dance class, but…

  10. Development of the Ghent Multidimensional Somatic Complaints Scale

    ERIC Educational Resources Information Center

    Beirens, Koen; Fontaine, Johnny R. J.

    2010-01-01

    The present study aimed at developing a new scale that operationalizes a hierarchical model of somatic complaints. First, 63 items representing a wide range of symptoms and sensations were compiled from somatic complaints scales and emotion literature. These complaints were rated by Belgian students (n = 307) and Belgian adults (n = 603).…

  11. CHAPTER 1. GENE EXPRESSION PATTERNS DURING SOMATIC EMBRYO DEVELOPMENT AND

    E-print Network

    Carriquiry, Alicia

    1 CHAPTER 1. GENE EXPRESSION PATTERNS DURING SOMATIC EMBRYO DEVELOPMENT AND GERMINATION IN MAIZE Hi generated from embryogenic calli induced to undergo embryo maturation and germination. Over 1,000 genes in the 12,060 element arrays showed significant time variation during somatic embryo develop- ment

  12. Somatic Symptoms in Children from Three Ethnic Groups.

    ERIC Educational Resources Information Center

    Canino, Glorisa; Gonzalez, Gloria; Ramirez, Rafael

    A study compared the rates of somatic symptoms associated with anxiety disorder in African Americans, Hispanics residing in Puerto Rico, and European American children. A total of 1,285 children were interviewed, along with their primary caretakers. Headaches were the most frequently endorsed somatic symptom, with half of the total sample…

  13. Reprogramming of human somatic cells to pluripotency with defined factors

    E-print Network

    Brutlag, Doug

    in somatic cells by nuclear transfer into oocytes1 and fusion with embryonic stem cells2 , and for male germARTICLES Reprogramming of human somatic cells to pluripotency with defined factors In-Hyun Park1. William Lensch1 & George Q. Daley1 Pluripotency pertains to the cells of early embryos that can generate

  14. Recent advancements in cloning by somatic cell nuclear transfer

    PubMed Central

    Ogura, Atsuo; Inoue, Kimiko; Wakayama, Teruhiko

    2013-01-01

    Somatic cell nuclear transfer (SCNT) cloning is the sole reproductive engineering technology that endows the somatic cell genome with totipotency. Since the first report on the birth of a cloned sheep from adult somatic cells in 1997, many technical improvements in SCNT have been made by using different epigenetic approaches, including enhancement of the levels of histone acetylation in the chromatin of the reconstructed embryos. Although it will take a considerable time before we fully understand the nature of genomic programming and totipotency, we may expect that somatic cell cloning technology will soon become broadly applicable to practical purposes, including medicine, pharmaceutical manufacturing and agriculture. Here we review recent progress in somatic cell cloning, with a special emphasis on epigenetic studies using the laboratory mouse as a model. PMID:23166393

  15. A Digital Framework to Build, Visualize and Analyze a Gene Expression Atlas with Cellular Resolution in Zebrafish Early Embryogenesis

    E-print Network

    Luengo-Oroz, Miguel A.

    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, ...

  16. Development of coffee somatic and zygotic embryos to plants differs in the morphological, histochemical and hydration aspects.

    PubMed

    Etienne, Hervé; Bertrand, Benoît; Georget, Frédéric; Lartaud, Marc; Montes, Fabienne; Dechamp, Eveline; Verdeil, Jean-Luc; Barry-Etienne, Dominique

    2013-06-01

    In Coffea arabica L., the development of direct sowing of somatic embryos (SE) in planting substrate, with subsequent nursery production of plants, has promoted the industrialization of somatic embryogenesis. However, plant conversion rates are still low and require improvements to enhance the cost-effectiveness of commercial micropropagation. With the aim of improving plant regeneration from SE, we studied the morphological and histological criteria and water characteristics during germination and plant conversion of zygotic embryos (ZE) and SE. At the cotyledonary stage, SE produced in a 1 l RITA(®) temporary immersion bioreactor (area 55.8 cm(2)) were morphologically similar in size (2-3 mm) but abnormal as compared with mature ZE. Protein and starch reserve levels were extremely low throughout germination and conversion to plantlets, while the water status remained steady [water content (WC) from 76 to 87%, ? from -0.37 to -0.47 MPa, pressure potential from 0.69 to 0.24 MPa]. In ZE, spectacular hydration occurred during the first 3 weeks (WC from 37 to 75%; ? from -6.24 to -1.0 MPa). Cotyledons remained undifferentiated for 10 weeks after sowing. Conversely, after only 3 weeks under germination conditions in a RITA(®) bioreactor, spongy and palisade parenchyma and stomata formed in SE cotyledons. The ZE plant conversion was faster than that of SE (14 vs. 22 weeks) and more efficient (rates 96 vs. 55%), with much more substantial hypocotyl and cotyledon development. The use of a new 5 l MATIS(®) bioreactor (area 355 cm(2)), designed especially to favor embryo dispersion and light transmittance to SE, markedly improved the embryo-to-plantlet conversion rate (91%). These results highlight the morphological heterogeneity and lack of protein reserves in SE at the beginning of the germination phase and marked differences in water characteristics. However, they also reveal high phenotypic plasticity, leading to a highly efficient plantlet conversion rate due to better embryo dispersion and light transmittance in more horizontal bioreactors. PMID:23729274

  17. An iTRAQ-Based Proteomics Approach to Clarify the Molecular Physiology of Somatic Embryo Development in Prince Rupprecht's Larch (Larix principis-rupprechtii Mayr)

    PubMed Central

    Zhao, Jian; Li, Hui; Fu, Shuangbin; Chen, Bo; Sun, Wenting; Zhang, Junqi; Zhang, Jinfeng

    2015-01-01

    Prince Rupprecht's larch (Larix principis-rupprechtii Mayr) is a native high-value forest tree species in North China whose clonal propagation through somatic embryogenesis (SE) has the potential to rapidly capture the benefits of breeding or genetic engineering programs and to improve raw material uniformity and quality. To date, research has focused on clarifying the molecular mechanism of SE, but proteomic studies are still in the early stages. In this study, isobaric tags for relative and absolute quantitation (iTRAQ) analysis was performed on three developmental stages of SE in L. principis-rupprechtii in an attempt to identify a wide range of proteins that are regulated differentially during this process. Proteins were extracted and analyzed from the pro-embryogenic mass (PEM), globular embryo (GE), and cotyledon embryo (CE) stages of embryo development. We detected 503 proteins in total and identified 96 proteins expressed differentially during different developmental stages. The identified proteins were analyzed further to provide information about their expression patterns and functions during SE. Four clusters of proteins based on shared expression profiles were generated. Functional analysis showed that proteins involved in primary metabolism, phosphorylation, and oxidation reduction were upregulated during somatic embryo development. This work provides novel insights into the process of larch embryo development in vitro and a basis for further study of the biological process and opportunities for practical application of this knowledge. PMID:25781987

  18. Light-emitting diodes and their potential in callus growth, plantlet development and saponin accumulation during somatic embryogenesis of Panax vietnamensis Ha et Grushv.

    PubMed Central

    Nhut, Duong Tan; Huy, Nguyen Phuc; Tai, Ngo Thanh; Nam, Nguyen Ba; Luan, Vu Quoc; Hien, Vu Thi; Tung, Hoang Thanh; Vinh, Bui The; Luan, Tran Cong

    2015-01-01

    In recent years, LED (light-emitting diode) has been the subject of research within the field of plant growth and development. However, there has been little discussion about using LED in vitro cultures of Panax vietnamensis, one of the important medicinal plants belonging to the Panax genus. This study examines the influence of various LED lamps on callus growth and plant formation of P. vietnamensis. Results show significant differences in growth and development, as various light conditions were suitable for different stages. Callus of 70 mg in fresh weight cultured under yellow LEDs resulted in growth of 1197 mg in fresh weight and 91.7 mg of dry weight, within a period of three months. The most effective plant formation was obtained when embryogenic calli were cultured under the combination of 60% red LED and 40% blue LED with an average of 11.21 plantlets per explant; the shoot clump fresh weight and dry weight were of 1147 and 127 mg, respectively, and the average plant height was 3.1 cm. It was also shown that this light condition was the most efficient for P. vietnamensis in vitro plant growth and development. This study provided additional evidence regarding the influence of different LEDs on ginsenoside production applying high-performance liquid chromatography (HPLC) analysis with photo-diode array (PDA) detection at ultraviolet (UV) wavelength 203 nm. The highest MR2 content was recorded when plants maintained under 20% red LED combined with 80% blue LED. However, the highest Rg1 and Rb1 content was found under fluorescent light. The results presented might provide new strategies using LEDs for adequate micropropagation protocols of P. vietnamensis. PMID:26019644

  19. Somatic symptoms in traumatized children and adolescents.

    PubMed

    Kugler, Brittany B; Bloom, Marlene; Kaercher, Lauren B; Truax, Tatyana V; Storch, Eric A

    2012-10-01

    Childhood exposure to trauma has been associated with increased rates of somatic symptoms (SS), which may contribute to diminished daily functioning. One hundred and sixty-one children residing at a residential treatment home who had experienced neglect and/or abuse were administered the Trauma Symptom Checklist for Children (TSCC), the Multidimensional Anxiety Scale for Children, and the Children's Depression Inventory (CDI). Primary caregivers completed the Child Behavior Checklist. Two composite measures of SS were formed to represent both child- and caregiver-rated SS. Over 95% of children endorsed at least one SS on the child-rated measure. Children who had experienced sexual abuse had higher rates of SS relative to children who had not. Child-rated SS were highly correlated with the CDI total score and the TSCC subscales of anxiety, depression, posttraumatic stress, dissociation, and anger. The TSCC anxiety subscale mediated the relationship between sexual abuse and child-rated SS. PMID:22395849

  20. The Somatic Genomic Landscape of Glioblastoma

    PubMed Central

    Brennan, Cameron W.; Verhaak, Roel G.W.; McKenna, Aaron; Campos, Benito; Noushmehr, Houtan; Salama, Sofie R.; Zheng, Siyuan; Chakravarty, Debyani; Sanborn, J. Zachary; Berman, Samuel H.; Beroukhim, Rameen; Bernard, Brady; Wu, Chang-Jiun; Genovese, Giannicola; Shmulevich, Ilya; Barnholtz-Sloan, Jill; Zou, Lihua; Vegesna, Rahulsimham; Shukla, Sachet A.; Ciriello, Giovanni; Yung, WK; Zhang, Wei; Sougnez, Carrie; Mikkelsen, Tom; Aldape, Kenneth; Bigner, Darell D.; Van Meir, Erwin G.; Prados, Michael; Sloan, Andrew; Black, Keith L.; Eschbacher, Jennifer; Finocchiaro, Gaetano; Friedman, William; Andrews, David W.; Guha, Abhijit; Iacocca, Mary; O’Neill, Brian P.; Foltz, Greg; Myers, Jerome; Weisenberger, Daniel J.; Penny, Robert; Kucherlapati, Raju; Perou, Charles M.; Hayes, D. Neil; Gibbs, Richard; Marra, Marco; Mills, Gordon B.; Lander, Eric; Spellman, Paul; Wilson, Richard; Sander, Chris; Weinstein, John; Meyerson, Matthew; Gabriel, Stacey; Laird, Peter W.; Haussler, David; Getz, Gad; Chin, Lynda

    2013-01-01

    We describe the landscape of somatic genomic alterations based on multi-dimensional and comprehensive characterization of more than 500 glioblastoma tumors (GBMs). We identify several novel mutated genes as well as complex rearrangements of signature receptors including EGFR and PDGFRA. TERT promoter mutations are shown to correlate with elevated mRNA expression, supporting a role in telomerase reactivation. Correlative analyses confirm that the survival advantage of the proneural subtype is conferred by the G-CIMP phenotype, and MGMT DNA methylation may be a predictive biomarker for treatment response only in classical subtype GBM. Integrative analysis of genomic and proteomic profiles challenges the notion of therapeutic inhibition of a pathway as an alternative to inhibition of the target itself. These data will facilitate the discovery of therapeutic and diagnostic target candidates, the validation of research and clinical observations and the generation of unanticipated hypotheses that can advance our molecular understanding of this lethal cancer. PMID:24120142

  1. Division plane determination during plant somatic cytokinesis.

    PubMed

    Van Damme, Daniel

    2009-12-01

    Division plane determination in plant cells involves the transformation of the cortical microtubular array into a preprophase band (PPB) with the nucleus anchored at the center. This likely occurs through polarity cues controlling proteins affecting cytoskeletal dynamics. Crosstalk with cell cycle machinery should assure that this happens in concert with cell cycle progression. Before PPB breakdown, targeted deposition of factors at the position of the PPB translates this position into a signal which remains present throughout cytokinesis and directs the centrifugal growing cell plate to the correct cortical position. Anchoring and maturation of the cell plate ultimately divides the two daughter cells. This review aims to provide an up-to-date overview of the mechanisms and molecular players in division plane determination in plant somatic cytokinesis. PMID:19850508

  2. Susceptible periods during embryogenesis of the heart and endocrine glands.

    PubMed Central

    Sadler, T W

    2000-01-01

    One of the original principles of teratology states that, "Susceptibility to teratogenesis varies with the developmental stage at the time of exposure to an adverse influence" [Wilson JG. Environment and Birth Defects. New York:Academic Press, 1973]. The time of greatest sensitivity encompasses the period of organ formation during weeks 3-8 following fertilization in human gestation. At this time, stem cell populations for each organ's morphogenesis are established and inductive events for the initiation of differentiation occur. Structural defects of the heart and endocrine system are no exception to this axiom and have their origins during this time frame. Although the function and maturation of these organs may be affected at later stages, structural defects and loss of cell types usually occur during these early phases of development. Thus, to determine critical windows for studying mechanisms of teratogenesis, it is essential to understand the developmental processes that establish these organs. Images Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10 Figure 11 Figure 12 PMID:10852854

  3. Dorsomorphin inhibits BMP signals required for embryogenesis and iron metabolism

    PubMed Central

    Yu, Paul B; Hong, Charles C; Sachidanandan, Chetana; Babitt, Jodie L; Deng, Donna Y; Hoyng, Stefan A; Lin, Herbert Y; Bloch, Kenneth D; Peterson, Randall T

    2009-01-01

    Bone morphogenetic protein (BMP) signals coordinate developmental patterning and have essential physiological roles in mature organisms. Here we describe the first known small-molecule inhibitor of BMP signaling—dorsomorphin, which we identified in a screen for compounds that perturb dorsoventral axis formation in zebrafish. We found that dorsomorphin selectively inhibits the BMP type I receptors ALK2, ALK3 and ALK6 and thus blocks BMP-mediated SMAD1/5/8 phosphorylation, target gene transcription and osteogenic differentiation. Using dorsomorphin, we examined the role of BMP signaling in iron homeostasis. In vitro, dorsomorphin inhibited BMP-, hemojuvelin- and interleukin 6–stimulated expression of the systemic iron regulator hepcidin, which suggests that BMP receptors regulate hepcidin induction by all of these stimuli. In vivo, systemic challenge with iron rapidly induced SMAD1/5/8 phosphorylation and hepcidin expression in the liver, whereas treatment with dorsomorphin blocked SMAD1/5/8 phosphorylation, normalized hepcidin expression and increased serum iron levels. These findings suggest an essential physiological role for hepatic BMP signaling in iron-hepcidin homeostasis. PMID:18026094

  4. Evidence for active maintenance of phylotranscriptomic hourglass patterns in animal and plant embryogenesis.

    PubMed

    Drost, Hajk-Georg; Gabel, Alexander; Grosse, Ivo; Quint, Marcel

    2015-05-01

    The developmental hourglass model has been used to describe the morphological transitions of related species throughout embryogenesis. Recently, quantifiable approaches combining transcriptomic and evolutionary information provided novel evidence for the presence of a phylotranscriptomic hourglass pattern across kingdoms. As its biological function is unknown it remains speculative whether this pattern is functional or merely represents a nonfunctional evolutionary relic. The latter would seriously hamper future experimental approaches designed to test hypotheses regarding its function. Here, we address this question by generating transcriptome divergence index (TDI) profiles across embryogenesis of Danio rerio, Drosophila melanogaster, and Arabidopsis thaliana. To enable meaningful evaluation of the resulting patterns, we develop a statistical test that specifically assesses potential hourglass patterns. Based on this objective measure we find that two of these profiles follow a statistically significant hourglass pattern with the most conserved transcriptomes in the phylotypic periods. As the TDI considers only recent evolutionary signals, this indicates that the phylotranscriptomic hourglass pattern is not a rudiment but possibly actively maintained, implicating the existence of some linked biological function associated with embryogenesis in extant species. PMID:25631928

  5. Traces of embryogenesis are the same in monozygotic and dizygotic twins: not compatible with double ovulation

    PubMed Central

    Boklage, Charles E.

    2009-01-01

    Common knowledge of over a century has it that monozygotic and dizygotic twinning events occur by unrelated mechanisms: monozygotic twinning ‘splits’ embryos, producing anomalously re-arranged embryogenic asymmetries; dizygotic twinning begins with independent ovulations yielding undisturbed parallel embryogeneses with no expectation of departures from singleton outcomes. The anomalies statistically associated with twin births are due to the re-arranged embryos of the monozygotics. Common knowledge further requires that dizygotic pairs are dichorionic; monochorionicity is exclusive to monozygotic pairs. These are fundamental certainties in the literature of twin biology. Multiple observations contradict those common knowledge understandings. The double ovulation hypothesis of dizygotic twinning is untenable. Girl–boy twins differ subtly from all other humans of either sex, absolutely not representative of all dizygotics. Embryogenesis of dizygotic twins differs from singleton development at least as much as monozygotic embryogenesis does, and in the same ways, and the differences between singletons and twins of both zygosities represent a coherent system of re-arranged embryogenic asymmetries. Dizygotic twinning and monozygotic twinning have the same list of consequences of anomalous embryogenesis. Those include an unignorable fraction of dizygotic pairs that are in fact monochorionic, plus many more sharing co-twins’ cells in tissues other than a common chorion. The idea that monozygotic and dizygotic twinning events arise from the same embryogenic mechanism is the only plausible hypothesis that might explain all of the observations. PMID:19252194

  6. Evidence for Active Maintenance of Phylotranscriptomic Hourglass Patterns in Animal and Plant Embryogenesis

    PubMed Central

    Drost, Hajk-Georg; Gabel, Alexander; Grosse, Ivo; Quint, Marcel

    2015-01-01

    The developmental hourglass model has been used to describe the morphological transitions of related species throughout embryogenesis. Recently, quantifiable approaches combining transcriptomic and evolutionary information provided novel evidence for the presence of a phylotranscriptomic hourglass pattern across kingdoms. As its biological function is unknown it remains speculative whether this pattern is functional or merely represents a nonfunctional evolutionary relic. The latter would seriously hamper future experimental approaches designed to test hypotheses regarding its function. Here, we address this question by generating transcriptome divergence index (TDI) profiles across embryogenesis of Danio rerio, Drosophila melanogaster, and Arabidopsis thaliana. To enable meaningful evaluation of the resulting patterns, we develop a statistical test that specifically assesses potential hourglass patterns. Based on this objective measure we find that two of these profiles follow a statistically significant hourglass pattern with the most conserved transcriptomes in the phylotypic periods. As the TDI considers only recent evolutionary signals, this indicates that the phylotranscriptomic hourglass pattern is not a rudiment but possibly actively maintained, implicating the existence of some linked biological function associated with embryogenesis in extant species. PMID:25631928

  7. Developmental biochemistry of cottonseed embryogenesis and germination. XIII. Regulation of biosynthesis of principal storage proteins

    SciTech Connect

    Dure, L. III; Galau, G.A.

    1981-07-01

    The synthesis of the principal cottonseed storage proteins during embryogenesis was followed by analyses of protein synthesized in vivo and from purified RNA in vitro in the wheat germ system. The kinetics of in vivo labeling as well as immunochemical cross-reactivity indicate that the 52- and 48-kilodalton mature storage protein sets are derived from 70- and 67-kilodalton precursor protein sets that are abundant proteins in embryonic cotyledons and disappear in late embryogenesis. Identification of the initial translation products of the storage protein mRNA has not been clearly established although products of apparent molecular weights of 69,000 and 60,000 are the likely storage protein precursors. Storage protein synthesis falls off markedly in late embryogenesis simultaneously with the loss of a superabundant class of mRNAs that are presumed to be those for the storage proteins. The synthesis of these proteins ceases abruptly when immature embryos are removed from the boll and allowed to germinate precociously or when this precocious germination is prevented by incubation in abscisic acid. Thus, abscisic acid is not implicated in the expression of the storage protein genes. A scheme involving co-translational processing into vesicles, glycosylation, and slow in situ cleavage to produce the mature storage proteins is proposed.

  8. Oxygen changes drive non-uniform scaling in Drosophila melanogaster embryogenesis

    PubMed Central

    Kuntz, Steven G.; Eisen, Michael B.

    2015-01-01

    We previously demonstrated that, while changes in temperature produce dramatic shifts in the time elapsed during Drosophila melanogaster embryogenesis, the relative timing of events within embryogenesis does not change. However, it was unclear if this uniform scaling is an intrinsic property of developing embryos, or if it is specific to thermal fluctuations. To investigate this, here we characterize the embryonic response to changes in oxygen concentration, which also impact developmental rate, using time-lapse imaging, and find it fundamentally different from the temperature response. Most notably, changes in oxygen levels drive developmental heterochrony, with the timing of several morphological processes showing distinct scaling behaviors. Gut formation is severely slowed by decreases in oxygen, while head involution and syncytial development are less impacted than the rest of development, and the order of several developmental landmarks is inverted at different oxygen levels. These data reveal that the uniform scaling seen with changes in temperature is not a trivial consequence of adjusting developmental rate. The developmental rate changes produced by changing oxygen concentrations dwarf those induced by temperature, and greatly impact survival. While extreme temperatures increase early embryo mortality, mild hypoxia increases arrest and death during mid-embryogenesis and mild hyperoxia increases survival over normoxia. PMID:26673611

  9. Nuclear lamins and peripheral nuclear antigens during fertilization and embryogenesis in mice and sea urchins

    NASA Technical Reports Server (NTRS)

    Schatten, G.; Schatten, H.; Simerly, C.; Maul, G. G.; Chaly, N.

    1985-01-01

    Nuclear structural changes during fertilization and embryogenesis in mice and sea urchins are traced using four antibodies. The oocytes from virgin female mice, morulae and blastocytes from mated females, and gametes from the sea urchin Lytechnius variegatis are studied using mouse monoclonal antibodies to nuclear lamin A/C, monoclonal antibody to P1, human autoimmune antibodies to lamin A/C, and to lamin B. The mouse fertilization data reveal no lamins on the oocyte; however, lamins are present on the pronuclei, and chromosomes are found on the oocytes and pronuclei. It is detected that on the sea urchin sperm the lamins are reduced to acrosomal and centriolar fossae and peripheral antigens are around the sperm nucleus. The mouse sperm bind lamin antibodies regionally and do not contain antigens. Lamins and antigens are observed on both pronuclei and chromosomes during sea urchin fertilization. Mouse embryogenesis reveals that lamin A/C is not recognized at morula and blastocyst stages; however, lamin B stains are retained. In sea urchin embryogenesis lamin recognition is lost at the blastrula, gastrula, and plutei stages. It is noted that nuclear lamins lost during spermatogenesis are restored at fertilization and peripheral antigens are associated with the surface of chromosomes during meiosis and mitosis and with the periphery of the pronuclei and nuclei during interphase.

  10. Nuclear lamins and peripheral nuclear antigens during fertilization and embryogenesis in mice and sea urchins

    SciTech Connect

    Schatten, G.; Schatten, H.; Simerly, C.; Maul, G.G.; Chaly, N.

    1985-07-01

    Nuclear structural changes during fertilization and embryogenesis in mice and sea urchins are traced using four antibodies. The oocytes from virgin female mice, morulae and blastocytes from mated females, and gametes from the sea urchin Lytechnius variegatis are studied using mouse monoclonal antibodies to nuclear lamin A/C, monoclonal antibody to P1, human autoimmune antibodies to lamin A/C, and to lamin B. The mouse fertilization data reveal no lamins on the oocyte; however, lamins are present on the pronuclei, and chromosomes are found on the oocytes and pronuclei. It is detected that on the sea urchin sperm the lamins are reduced to acrosomal and centriolar fossae and peripheral antigens are around the sperm nucleus. The mouse sperm bind lamin antibodies regionally and do not contain antigens. Lamins and antigens are observed on both pronuclei and chromosomes during sea urchin fertilization. Mouse embryogenesis reveals that lamin A/C is not recognized at morula and blastocyst stages; however, lamin B stains are retained. In sea urchin embryogenesis lamin recognition is lost at the blastrula, gastrula, and plutei stages. It is noted that nuclear lamins lost during spermatogenesis are restored at fertilization and peripheral antigens are associated with the surface of chromosomes during meiosis and mitosis and with the periphery of the pronuclei and nuclei during interphase. 32 references.

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

    PubMed Central

    Marchini, Chiara; Airi, Valentina; Fontana, Roberto; Tortorelli, Giada; Rocchi, Marta; Falini, Giuseppe; Levy, Oren; Dubinsky, Zvy; Goffredo, Stefano

    2015-01-01

    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. PMID:26513159

  12. Insomnia in relation to depression and somatic symptoms.

    PubMed

    El-Anzi, Freih O

    2006-08-01

    A sample of 358 Kuwaiti volunteer college students responded to the Insomnia Scale, the Somatic Symptoms Inventory, and the Center for Epidemiologic Studies-Depression Scale. The only significant sex difference was in somatic symptoms on which women had a higher mean score than the men. Correlations between scores on the Insomnia Scale and both Depression scales were .51 and .54 and for Somatic Symptoms were .53 and .61 (p < .01) among men and women, respectively. The factor analysis of the intercorrelations yielded a highly loaded general factor for Psychological Disorder in both samples. PMID:17037463

  13. Age and sex differences in somatic complaints associated with depression.

    PubMed

    Berry, J M; Storandt, M; Coyne, A

    1984-07-01

    Following the procedure used by Zemore and Eames (1979) with the Beck Depression Inventory, the 20 items of the Zung Self-Rating Depression Scale were categorized as either somatic or psychological symptoms of depression. Scores of 179 college students and 462 community-dwelling older adults revealed significant, though small, age differences in somatic complaints. Somatic complaints were especially prominent in older women. Age differences in psychological symptoms of depression were not significant. Diagnosis of depression in later life, especially in women, may be confounded by the use of physical symptoms of depression that are comparable to physical changes that accompany the aging process. PMID:6588128

  14. Computer Science Induction to

    E-print Network

    Berger, Ulrich

    Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Supervision Regulations Progression Regulations Computer Science Induction to Postgraduate Research Studies Ulrich Berger Head of Postgraduate Research Department of Computer Science Swansea

  15. Electromagnetic induction methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Electromagnetic induction geophysical methods are finding greater and greater use for agricultural purposes. Electromagnetic induction methods measure the electrical conductivity (or resistivity) for a bulk volume of soil directly beneath the surface. An instrument called a ground conductivity meter...

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

    PubMed

    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 ?-(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. PMID:25907568

  17. Reprogramming of somatic cells induced by fusion of embryonic stem cells using hemagglutinating virus of Japan envelope (HVJ-E)

    SciTech Connect

    Yue, Xiao-shan; Department of Biomolecular Engineering, Graduate School of Bioscience and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501 ; Fujishiro, Masako; Toyoda, Masashi; Akaike, Toshihiro; Ito, Yoshihiro; Department of Biomolecular Engineering, Graduate School of Bioscience and Technology, Tokyo Institute of Technology, Nagatsuta-cho, Midori-ku, Yokohama-shi, Kanagawa 226-8501

    2010-04-16

    In this research, hemagglutinating virus of Japan envelope (HVJ-E) was used to reprogram somatic cells by fusion with mouse embryonic stem (ES) cells. Neomycin-resistant mouse embryonic fibroblasts (MEFs) were used as somatic cells. Nanog-overexpressing puromycin-resistant EB3 cells were used as mouse ES cells. These two cells were fused by exposing to HVJ-E and the generated fusion cells were selected by puromycin and G418 to get the stable fusion cell line. The fusion cells form colonies in feeder-free culture system. Microsatellite analysis of the fusion cells showed that they possessed genes from both ES cells and fibroblasts. The fusion cells were tetraploid, had alkali phosphatase activity, and expressed stem cell marker genes such as Pou5f1, Nanog, and Sox2, but not the fibroblast cell marker genes such as Col1a1 and Col1a2. The pluripotency of fusion cells was confirmed by their expression of marker genes for all the three germ layers after differentiation induction, and by their ability to form teratoma which contained all the three primary layers. Our results show that HVJ-E can be used as a fusion reagent for reprogramming of somatic cells.

  18. Reprogramming human somatic cells to pluripotency using RNA

    E-print Network

    Angel, Matthew (Matthew M.)

    2012-01-01

    Somatic cells can be reprogrammed to a pluripotent stem-cell state by ectopic expression of defined proteins. However, existing reprogramming methods take several weeks, suffer from low efficiencies, and most use DNA-based ...

  19. Inference of Tumor Phylogenies with Improved Somatic Mutation Discovery

    E-print Network

    Sidow, Arend

    Inference of Tumor Phylogenies with Improved Somatic Mutation Discovery RAHELEH SALARI,1 SYED tumors, current methods do not exploit available phylogenetic infor- mation to improve the accuracy words: cancer evolution, genetic variations, tumor phylogeny. 1. INTRODUCTION Next-generation genome

  20. INTRODUCTION A hierarchy of regulatory genes controls somatic sex

    E-print Network

    Baker, Bruce S.

    the fruitless (fru) gene (Ryner et al., 1996). dsx is required for all known aspects of somatic sexual of fru appears to be required for the sexual differentiation of only a small set of cells in the CNS

  1. Anxiety, depression, and somatization in DSM-III hypochondriasis.

    PubMed

    Kellner, R; Abbott, P; Winslow, W W; Pathak, D

    1989-01-01

    To assess the severity of distress and of somatization in hypochondriasis, the authors administered several validated self-rating scales of depression, anxiety, somatic symptoms, and anger/hostility to 21 psychiatric outpatients with the DSM-III diagnosis of hypochondriasis and to matched groups of other nonpsychotic psychiatric patients, family practice patients, and employees. Anxiety and somatic symptoms were highest in hypochondriacal patients; depression and anger/hostility did not differ from those of other psychiatric patients but were higher than in the other groups. The findings do not support the theory that hypochondriasis is a defense against anxiety or that it is a masked depression or depressive equivalent. The findings are consistent with the view that the interaction of severe anxiety and severe somatic symptoms is a common feature of the psychopathology of hypochondriasis. PMID:2913598

  2. Modality specific neural correlates of auditory and somatic hallucinations

    PubMed Central

    Shergill, S; Cameron, L; Brammer, M; Williams, S; Murray, R; McGuire, P

    2001-01-01

    Somatic hallucinations occur in schizophrenia and other psychotic disorders, although auditory hallucinations are more common. Although the neural correlates of auditory hallucinations have been described in several neuroimaging studies, little is known of the pathophysiology of somatic hallucinations. Functional magnetic resonance imaging (fMRI) was used to compare the distribution of brain activity during somatic and auditory verbal hallucinations, occurring at different times in a 36 year old man with schizophrenia. Somatic hallucinations were associated with activation in the primary somatosensory and posterior parietal cortex, areas that normally mediate tactile perception. Auditory hallucinations were associated with activation in the middle and superior temporal cortex, areas involved in processing external speech. Hallucinations in a given modality seem to involve areas that normally process sensory information in that modality.?? PMID:11606687

  3. Human Embryonic Stem Cells Derived by Somatic Cell Nuclear Transfer

    PubMed Central

    Tachibana, Masahito; Amato, Paula; Sparman, Michelle; Gutierrez, Nuria Marti; Tippner-Hedges, Rebecca; Ma, Hong; Kang, Eunju; Fulati, Alimujiang; Lee, Hyo-Sang; Sritanaudomchai, Hathaitip; Masterson, Keith; Larson, Janine; Eaton, Deborah; Sadler-Fredd, Karen; Battaglia, David; Lee, David; Wu, Diana; Jensen, Jeffrey; Patton, Phillip; Gokhale, Sumita; Stouffer, Richard L.; Wolf, Don; Mitalipov, Shoukhrat

    2013-01-01

    SUMMARY Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state. PMID:23683578

  4. [Somatic mutations in nuclear and mitochondrial DNA]. Progress report

    SciTech Connect

    Not Available

    1992-09-01

    The study is concerned the design of new assays that may detect rare somatic mutations in nuclear and mitochondrial DNA, which may increase upon exposure to mutagens, and thus become a marker of human exposure to such mutagens. Two assays for somatic mutation were presented, one for mitochondrial DNA deletions which was developed by the author, and one for deletions of the ADA gene which resides in the nucleus.

  5. Selection against somatic parasitism can maintain allorecognition in fungi.

    PubMed

    Czárán, Tamas; Hoekstra, Rolf F; Aanen, Duur K

    2014-12-01

    Fusion between multicellular individuals is possible in many organisms with modular, indeterminate growth, such as marine invertebrates and fungi. Although fusion may provide various benefits, fusion usually is restricted to close relatives by allorecognition, also called heterokaryon or somatic incompatibility in fungi. A possible selective explanation for allorecognition is protection against somatic parasites. Such mutants contribute less to colony functions but more to reproduction. However, previous models testing this idea have failed to explain the high diversity of allorecognition alleles in nature. These models did not, however, consider the possible role of spatial structure. We model the joint evolution of allorecognition and somatic parasitism in a multicellular organism resembling an asexual ascomycete fungus in a spatially explicit simulation. In a 1000-by-1000 grid, neighbouring individuals can fuse, but only if they have the same allotype. Fusion with a parasitic individual decreases the total reproductive output of the fused individuals, but the parasite compensates for this individual-level fitness reduction by a disproportional share of the offspring. Allorecognition prevents the invasion of somatic parasites, and vice versa, mutation towards somatic parasitism provides the selective conditions for extensive allorecognition diversity. On the one hand, if allorecognition diversity did not build up fast enough, somatic parasites went to fixation; conversely, once parasites had gone to fixation no allorecognition diversity built up. On the other hand, the mere threat of parasitism could select for high allorecognition diversity, preventing invasion of somatic parasites. Moderate population viscosity combined with weak global dispersal was optimal for the joint evolution of allorecognition and protection against parasitism. Our results are consistent with the widespread occurrence of allorecognition in fungi and the low degree of somatic parasitism. We discuss the implications of our results for allorecognition in other organism groups. PMID:25305337

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

    PubMed

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

    2015-09-01

    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. PMID:26260241

  7. Somatic mosaicism in plants with special reference to somatic crossing over

    PubMed Central

    Vig, Baldev K.

    1978-01-01

    Plant systems in use for the detection of environmental mutagens appear capable of detecting all types of genetic effects which can be studied in animals. The study of somatic mosaicism, however, is better developed in plants than in higher animals. A case is presented here which shows the ability of plant systems in analyzing a host of genetic end points, including chromosome aberrations like deletions, somatic crossing over, numerical inequality, gene conversion, paramutations and point mutations. The systems in general use utilize certain varieties of Tradescantia, Glycine max, Nicotiana tabacum, Antirrhinum majus, Petunia hybrida, and Arabidopsis thaliana. Heterozygous plants or their homozygous counterparts with gene markers affecting chlorophyll development or anthocyanin in floral parts are exploited in these studies. Mutagens produce different frequencies of different types of spots typical of the mode of action of the agent. Analysis of these parameters may be used to predict, at least qualitatively, the kind of genetic damage that might be produced in man. Besides, one can test the validity of interpretation by traditional progeny tests of plants raised from tissue culture from sectors as in Nicotiana and/or by precursor analysis as done in Antirrhinum. The study of mosaicism in plants offers quite inexpensive, rapid, and reliable tests of mutagenicity at least as a preliminary eukaryotic test system. ImagesFIGURE 1.FIGURE 1.FIGURE 2.FIGURE 9. PMID:367771

  8. The Maize MADS Box Gene ZmMADS3 Affects Node Number and Spikelet Development and Is Co-Expressed with ZmMADS1 during Flower Development, in Egg Cells, and Early Embryogenesis1

    PubMed Central

    Heuer, Sigrid; Hansen, Susanne; Bantin, Jörg; Brettschneider, Reinhold; Kranz, Erhard; Lörz, Horst; Dresselhaus, Thomas

    2001-01-01

    MADS box genes represent a large gene family of transcription factors with essential functions during flower development and organ differentiation processes in plants. Addressing the question of whether MADS box genes are involved in the regulation of the fertilization process and early embryo development, we have isolated two novel MADS box cDNAs, ZmMADS1 and ZmMADS3, from cDNA libraries of maize (Zea mays) pollen and egg cells, respectively. The latter gene is allelic to ZAP1. Transcripts of both genes are detectable in egg cells and in in vivo zygotes of maize. ZmMADS1 is additionally expressed in synergids and in central and antipodal cells. During early somatic embryogenesis, ZmMADS1 expression is restricted to cells with the capacity to form somatic embryos, and to globular embryos at later stages. ZmMADS3 is detectable only by more sensitive reverse transcriptase-PCR analyses, but is likewise expressed in embryogenic cultures. Both genes are not expressed in nonembryogenic suspension cultures and in isolated immature and mature zygotic embryos. During flower development, ZmMADS1 and ZmMADS3 are co-expressed in all ear spikelet organ primordia at intermediate stages. Among vegetative tissues, ZmMADS3 is expressed in stem nodes and displays a gradient with highest expression in the uppermost node. Transgenic maize plants ectopically expressing ZmMADS3 are reduced in height due to a reduced number of nodes. Reduction of seed set and male sterility were observed in the plants. The latter was due to absence of anthers. Putative functions of the genes during reproductive and vegetative developmental processes are discussed. PMID:11553732

  9. Identification of genomic regions required for DNA replication during Drosophila embryogenesis.

    PubMed

    Smith, A V; King, J A; Orr-Weaver, T L

    1993-11-01

    A collection of Drosophila deficiency stocks was examined by bromodeoxyuridine (BrdU) labeling of embryos to analyze the DNA replication patterns in late embryogenesis. This permitted us to screen 34% of the genome for genes that when absent in homozygous deficiencies affect the cell cycle or DNA replication. We found three genomic intervals that when deleted result in cessation of DNA replication in the embryo, 39D2-3;E2-F1, 51E and 75C5-7;F1. Embryos deleted for the 75C5-7;F1 region stop DNA replication at the time in embryogenesis when a G1 phase is added to the mitotic cell cycle and the larval tissues begin to become polytene. Thus, this interval may contain a gene controlling these cell cycle transitions. DNA replication arrests earlier in embryos homozygous for deletions for the other two regions. Analysis of the effects of deletions in the 39D2-3;E2-F1 region on DNA replication showed that the block to DNA replication correlates with deletion of the histone genes. We were able to identify a single, lethal complementation group in 51E, l(2)51Ec, that is responsible for the cessation of replication observed in this interval. Deficiencies that removed one of the Drosophila cdc2 genes and the cyclin A gene had no effect on replication during embryogenesis. Additionally, our analysis identified a gene, pimples, that is required for the proper completion of mitosis in the post-blastoderm divisions of the embryo. PMID:8293981

  10. Identification of Genomic Regions Required for DNA Replication during Drosophila Embryogenesis

    PubMed Central

    Smith, A. V.; King, J. A.; Orr-Weaver, T. L.

    1993-01-01

    A collection of Drosophila deficiency stocks was examined by bromodeoxyuridine (BrdU) labeling of embryos to analyze the DNA replication patterns in late embryogenesis. This permitted us to screen 34% of the genome for genes that when absent in homozygous deficiencies affect the cell cycle or DNA replication. We found three genomic intervals that when deleted result in cessation of DNA replication in the embryo, 39D2-3;E2-F1, 51E and 75C5-7;F1. Embryos deleted for the 75C5-7;F1 region stop DNA replication at the time in embryogenesis when a G(1) phase is added to the mitotic cell cycle and the larval tissues begin to become polytene. Thus, this interval may contain a gene controlling these cell cycle transitions. DNA replication arrests earlier in embryos homozygous for deletions for the other two regions. Analysis of the effects of deletions in the 39D2-3;E2-F1 region on DNA replication showed that the block to DNA replication correlates with deletion of the histone genes. We were able to identify a single, lethal complementation group in 51E, l(2)51Ec, that is responsible for the cessation of replication observed in this interval. Deficiencies that removed one of the Drosophila cdc2 genes and the cyclin A gene had no effect on replication during embryogenesis. Additionally, our analysis identified a gene, pimples, that is required for the proper completion of mitosis in the post-blastoderm divisions of the embryo. PMID:8293981

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

    PubMed

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

    2015-07-01

    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 3?g/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 30?g/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 30?g/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. PMID:25929836

  12. In Vitro Fertilization with Isolated, Single Gametes Results in Zygotic Embryogenesis and Fertile Maize Plants.

    PubMed Central

    Kranz, E; Lorz, H

    1993-01-01

    We demonstrate here the possibility of regenerating phenotypically normal, fertile maize plants via in vitro fertilization of isolated, single sperm and egg cells mediated by electrofusion. The technique leads to the highly efficient formation of polar zygotes, globular structures, proembryos, and transition-phase embryos and to the formation of plants from individually cultured fusion products. Regeneration of plants occurs via embryogenesis and occasionally by polyembryony and organogenesis. Flowering plants can be obtained within 100 days of gamete fusion. Regenerated plants were studied by karyological and morphological analyses, and the segregation of kernel color was determined. The hybrid nature of the plants was confirmed. PMID:12271084

  13. Morphology, Oviposition, and Embryogenesis in an Australian Population of Acrobeloides nanus

    PubMed Central

    Bird, Alan F.; De Ley, Paul; Bird, Jean

    1993-01-01

    A population of Acrobeloides nanus in Australia is described and illustrated, based on light and scanning electron microscopy. Embryogenesis from egg laying to hatching is followed over a wide range of temperatures. At 15 C, hatching occurs in about 125 hours and at 35 and 37.5 C after about 40 hours. At 40 C, egg development ceases early in cleavage. The capacity of A. nanus to develop over such a range of temperatures, and its anhydrobiotic capabilities, are discussed in relation to its survival and wide distribution in Australia. PMID:19279817

  14. [Reactivity of microvessels in the cerebral hemispheres and the skeletal muscles in chicken during second half of embryogenesis].

    PubMed

    Belichenko, V M; Turganbaeva, A S; Shoshenko, K A

    2014-02-01

    At Leghorn hens in the second half of embryogenesis and in 4-day-old chicks are studied reaction volume flow velocity (VF) in the superficial layers of the cerebral hemispheres and in skeletal muscle (Lazer Doppler FIowmetry) after the local influence of norepinephrine and sodium nitroprusside. It is shown that the response to these substances begins to manifest itself in the hemisphere in the last quarter of embryogenesis and authentically expressed by the end of it and in the chickens. It is noted that the response to these substances skeletal muscle VF (according to the new and previously published data on gastrocnemius and pectoral muscle) is also clearly manifested by the end of embryogenesis. PMID:25470895

  15. Sequential inductive learning

    SciTech Connect

    Gratch, J.

    1996-12-31

    This article advocates a new model for inductive learning. Called sequential induction, it helps bridge classical fixed-sample learning techniques (which are efficient but difficult to formally characterize), and worst-case approaches (which provide strong statistical guarantees but are too inefficient for practical use). Learning proceeds as a sequence of decisions which are informed by training data. By analyzing induction at the level of these decisions, and by utilizing the only enough data to make each decision, sequential induction provides statistical guarantees but with substantially less data than worst-case methods require. The sequential inductive model is also useful as a method for determining a sufficient sample size for inductive learning and as such, is relevant to learning problems where the preponderance of data or the cost of gathering data precludes the use of traditional methods.

  16. Assessing the New DSM-5 Diagnosis of Somatic Symptom Disorder.

    PubMed

    Barsky, Arthur J

    2016-01-01

    The conceptualization of somatization and what were previously termed somatoform disorders has changed substantially in the DSM-5 compared with previous diagnostic systems. The current diagnostic criteria for somatic symptom disorder (SSD) require the presence of symptoms (Criterion A) combined with a substantial impact of these symptoms on thoughts, emotions, and behaviors (Criterion B). In this issue of Psychosomatic Medicine, Toussaint et al. describe the development and empirical validation of a self-report questionnaire -the SSD-12- to assess the new psychological criteria (the "B criteria") of DSM-5 SSD. This is an important contribution because previously there was no questionnaire available to assess the B Criterion of SSD. The new DSM-5 criteria for SSD no longer require the absence of an adequate medical explanation for a somatic symptom, but rather define positive diagnostic criteria, focusing on the psychological impact of the somatic symptoms rather than their purported (medical) cause. Although this new conceptualization of somatization-related disorders has several advantages, seriously ill medical patients may well score high on the B Criterion for SSD on that basis alone and not because their psychological response to the medical illness is disproportionate or excessive. Measures of medical morbidity therefore need to be included in the interpretation of the SSD in individuals with severe medical conditions. Given the revised DSM-5 criteria, the newly developed and validated SSD-12 is a useful tool for diagnosing and monitoring treatment response in SSD. PMID:26599912

  17. Identification of somatic gene mutations in penile squamous cell carcinoma.

    PubMed

    Ferrándiz-Pulido, Carla; Hernández-Losa, Javier; Masferrer, Emili; Vivancos, Ana; Somoza, Rosa; Marés, Roso; Valverde, Claudia; Salvador, Carlos; Placer, Jose; Morote, Juan; Pujol, Ramon M; Ramon y Cajal, Santiago; de Torres, Ines; Toll, Agusti; García-Patos, Vicente

    2015-10-01

    There is a lack of studies on somatic gene mutations and cell signaling driving penile carcinogenesis. Our objective was to analyze somatic mutations in genes downstream of EGFR in penile squamous cell carcinomas, especially the mTOR and RAS/MAPK pathways. We retrospectively analyzed somatic mutations in 10 in situ and 65 invasive penile squamous cell carcinomas by using Sequenom's Mass Spectrometry iPlex Technology and Oncocarta v1.0 Panel. The DNA was extracted from FFPE blocks and we identified somatic missense mutations in three in situ tumors and in 19 invasive tumors, mostly in PIK3CA, KRAS, HRAS, NRAS, and PDGFA genes. Somatic mutations in the PIK3CA gene or RAS family genes were neither associated with tumor grade, stage or outcome, and were equally often identified in hrHPV positive and in hrHPV negative tumors that showed no p53 expression. Mutations in PIK3CA, KRAS, and HRAS are frequent in penile squamous cell carcinoma and likely play a role in the development of p53-negative tumors. Although the presence of these mutations does not seem to correlate with tumoral behavior or outcome, they could be biomarkers of treatment failure with anti-EGFR mAb in patients with penile squamous cell carcinoma. PMID:26216163

  18. Behavioural and psychological management of somatic symptom disorders: an overview.

    PubMed

    Sharma, Mahendra P; Manjula, M

    2013-02-01

    The number of patients who seek help at primary and secondary care for somatic symptoms which cannot be explained by any known medical condition is enormous. It has been proposed to rename 'somatoform disorders' in DSM-IV as 'somatic symptom disorders' in DSM-5. This is supposed to include disorders such as somatization disorder, hypochondriasis, undifferentiated somatoform disorder, pain disorder and factitious disorder. The reason for the renaming and grouping is that all these disorders involve presentation of physical symptoms and/or concern about medical illness. In the literature, there is considerable variation adopted with respect to diagnosis and in the approaches adopted for intervention. However, the common feature of these disorders is the chronicity, social dysfunction, occupational difficulties and the increased healthcare use and high level of dissatisfaction for both the clinician and the patient. A number of behavioural and psychological interventions for somatic symptoms have been carried out at primary, secondary and tertiary care settings and recently there have been more attempts to involve the primary care physicians in the psychological interventions. This review aims at giving an overview of the components of the behavioural and other psychological interventions available for addressing medically unexplained somatic symptoms and to present their efficacy. PMID:23383673

  19. A heat-inducible CRE/LOXP gene induction system in medaka.

    PubMed

    Kobayashi, Kayo; Kamei, Yasuhiro; Kinoshita, Masato; Czerny, Thomas; Tanaka, Minoru

    2013-01-01

    We established three lines of transgenic medaka, a heat-shock element (HSE) monitor line (hse-GFP line), heat-inducible driver lines (hse-cre lines), and effector lines (gapdh-loxP[DsRed]-GFP lines). We employed these to comprehensively analyze gene induction at different time points in various tissues. These analyses demonstrate a good response of synthetic HSEs by heat treatment during embryogenesis and the mosaic gene induction by cre/loxP-mediated recombination, thus providing practical information regarding the feasibility of a heat-inducible cre/loxP-mediated system in medaka. We also activated recombination by local heat-treatment using a metal probe and an infrared laser. Our results collectively indicate that these lines allow us to perform lineage tracing and mosaic analysis and provide the platform to investigate gene functions at later developmental stage and adult. PMID:23019184

  20. Time to Reconsider Stem Cell Induction Strategies

    PubMed Central

    Denker, Hans-Werner

    2012-01-01

    Recent developments in stem cell research suggest that it may be time to reconsider the current focus of stem cell induction strategies. During the previous five years, approximately, the induction of pluripotency in somatic cells, i.e., the generation of so-called ‘induced pluripotent stem cells’ (iPSCs), has become the focus of ongoing research in many stem cell laboratories, because this technology promises to overcome limitations (both technical and ethical) seen in the production and use of embryonic stem cells (ESCs). A rapidly increasing number of publications suggest, however, that it is now possible to choose instead other, alternative ways of generating stem and progenitor cells bypassing pluripotency. These new strategies may offer important advantages with respect to ethics, as well as to safety considerations. The present communication discusses why these strategies may provide possibilities for an escape from the dilemma presented by pluripotent stem cells (self-organization potential, cloning by tetraploid complementation, patenting problems and tumor formation risk). PMID:24710555

  1. Time to reconsider stem cell induction strategies.

    PubMed

    Denker, Hans-Werner

    2012-01-01

    Recent developments in stem cell research suggest that it may be time to reconsider the current focus of stem cell induction strategies. During the previous five years, approximately, the induction of pluripotency in somatic cells, i.e., the generation of so-called 'induced pluripotent stem cells' (iPSCs), has become the focus of ongoing research in many stem cell laboratories, because this technology promises to overcome limitations (both technical and ethical) seen in the production and use of embryonic stem cells (ESCs). A rapidly increasing number of publications suggest, however, that it is now possible to choose instead other, alternative ways of generating stem and progenitor cells bypassing pluripotency. These new strategies may offer important advantages with respect to ethics, as well as to safety considerations. The present communication discusses why these strategies may provide possibilities for an escape from the dilemma presented by pluripotent stem cells (self-organization potential, cloning by tetraploid complementation, patenting problems and tumor formation risk). PMID:24710555

  2. 3D Light-Sheet Fluorescence Microscopy of Cranial Neurons and Vasculature during Zebrafish Embryogenesis

    PubMed Central

    Park, Ok Kyu; Kwak, Jina; Jung, Yoo Jung; Kim, Young Ho; Hong, Hyun-Seok; Hwang, Byung Joon; Kwon, Seung-Hae; Kee, Yun

    2015-01-01

    Precise 3D spatial mapping of cells and their connections within living tissues is required to fully understand developmental processes and neural activities. Zebrafish embryos are relatively small and optically transparent, making them the vertebrate model of choice for live in vivo imaging. However, embryonic brains cannot be imaged in their entirety by confocal or two-photon microscopy due to limitations in optical range and scanning speed. Here, we use light-sheet fluorescence microscopy to overcome these limitations and image the entire head of live transgenic zebrafish embryos. We simultaneously imaged cranial neurons and blood vessels during embryogenesis, generating comprehensive 3D maps that provide insight into the coordinated morphogenesis of the nervous system and vasculature during early development. In addition, blood cells circulating through the entire head, vagal and cardiac vasculature were also visualized at high resolution in a 3D movie. These data provide the foundation for the construction of a complete 4D atlas of zebrafish embryogenesis and neural activity. PMID:26429501

  3. Fetal hematopoietic stem cells express MFG-E8 during mouse embryogenesis

    PubMed Central

    Lee, Jaehun; Choi, Byung-il; Park, Seo Young; An, Su Yeon; Han, Jiyou; Kim, Jong-Hoon

    2015-01-01

    The milk fat globule-EGF-factor 8 protein (MFG-E8) has been identified in various tissues, where it has an important role in intercellular interactions, cellular migration, and neovascularization. Previous studies showed that MFG-E8 is expressed in different cell types under normal and pathophysiological conditions, but its expression in hematopoietic stem cells (HSCs) during hematopoiesis has not been reported. In the present study, we investigated MFG-E8 expression in multiple hematopoietic tissues at different stages of mouse embryogenesis. Using immunohistochemistry, we showed that MFG-E8 was specifically expressed in CD34+ HSCs at all hematopoietic sites, including the yolk sac, aorta-gonad-mesonephros region, placenta and fetal liver, during embryogenesis. Fluorescence-activated cell sorting and polymerase chain reaction analyses demonstrated that CD34+ cells, purified from the fetal liver, expressed additional HSC markers, c-Kit and Sca-1, and that these CD34+ cells, but not CD34? cells, highly expressed MFG-E8. We also found that MFG-E8 was not expressed in HSCs in adult mouse bone marrow, and that its expression was confined to F4/80+ macrophages. Together, this study demonstrates, for the first time, that MFG-8 is expressed in fetal HSC populations, and that MFG-E8 may have a role in embryonic hematopoiesis. PMID:26206421

  4. Toxicity of lead, cadmium and mercury on embryogenesis, survival, growth and metamorphosis of Meretrix meretrix larvae.

    PubMed

    Wang, Qing; Liu, Baozhong; Yang, Hongsheng; Wang, Xiaoyu; Lin, Zhihua

    2009-10-01

    In order to assess the toxicity of heavy metals on the early development of Meretrix meretrix, the effects of mercury (Hg), cadmium (Cd) and lead (Pb) on embryogenesis, survival, growth and metamorphosis of larvae were investigated. The EC(50) for embryogenesis was 5.4 microg l(-1) for Hg, 1014 microg l(-1) for Cd and 297 microg l(-1) for Pb, respectively. The 96 h LC(50) for D-shaped larvae was 14.0 microg l(-1) for Hg, 68 microg l(-1) for Cd and 353 microg l(-1) for Pb, respectively. Growth was significantly retarded at 18.5 microg l(-1) (0.1 microM) for Hg, 104 microg l(-1) (1 microM) for Cd and 197 microg l(-1) (1 microM) for Pb, respectively. The EC(50) for metamorphosis, similar to 48 h LC(50), was higher than 96 h LC(50). Our results indicate that the early development of M. meretrix is highly sensitive to heavy metals and can be used as a test organism for ecotoxicology bioassays in temperate and subtropical regions. PMID:19504184

  5. The low molecular weight fraction of compounds released from immature wheat pistils supports barley pollen embryogenesis

    PubMed Central

    Lippmann, Rico; Friedel, Swetlana; Mock, Hans-Peter; Kumlehn, Jochen

    2015-01-01

    Pollen embryogenesis provides a useful means of generating haploid plants for plant breeding and basic research. Although it is well-established that the efficacy of the process can be enhanced by the provision of immature pistils as a nurse tissue, the origin and compound class of the signal molecule(s) involved is still elusive. Here, a micro-culture system was established to enable the culturing of populations of barley pollen at a density too low to allow unaided embryogenesis to occur, and this was then exploited to assess the effect of using various parts of the pistil as nurse tissue. A five-fold increase in the number of embryogenic calli formed was obtained by simply cutting the pistils in half. The effectiveness of the pistil-conditioned medium was transitory, since it needed replacement at least every 4 days to measurably ensure embryogenic development. The differential effect of various size classes of compounds present in the pistil-conditioned medium showed that the relevant molecule(s) was of molecular weight below 3 kDa. This work narrows down possible feeder molecules to lower molecular weight compounds and showed that the cellular origin of the active compound(s) is not specific to any tested part of the pistil. Furthermore, the increased recovery of calli during treatment with cut pistils may provide a useful tool for plant breeders and researchers using haploid technology in barley and other plant species. PMID:26217352

  6. Biological and biochemical properties of two Xenopus laevis N-acetylgalactosaminyltransferases with contrasting roles in embryogenesis

    PubMed Central

    Voglmeir, Josef; Laurent, Nicolas; Flitsch, Sabine L.; Oelgeschläger, Michael; Wilson, Iain B.H.

    2015-01-01

    The biosynthesis of mucin-type O-linked glycans in animals is initiated by members of the large family of polypeptide N-acetylgalactosaminyltransferases (GalNAc-Ts), which play important roles in embryogenesis, organogenesis, adult tissue homeostasis and carcinogenesis. Until now, the mammalian forms of these enzymes have been the best characterized. However, two N-acetylgalactosaminyltransferases (xGalNAc-T6 and xGalNAc-T16) from the African clawed frog (Xenopus laevis), which are most homologous to those encoded by the human GALNT6 and GALNT16 (GALNTL1) genes, were shown to have contrasting roles in TGF-?/BMP signaling in embryogenesis. In this study we have examined these two enzymes further and show differences in their in vivo function during X. laevis embyrogenesis as evidenced by in situ hybridization and overexpression experiments. In terms of enzymatic activity, both enzymes were found to be active towards the EA2 peptide, but display differential activity towards a peptide based on the sequence of ActR-IIB, a receptor relevant to TGF-?/BMP signaling. In summary, these data demonstrate that these two enzymes from different branches of the N-acetylgalactosaminyltransferase do not only display differential substrate specificities, but also specific and distinct expression pattern and biological activities in vivo. PMID:25447273

  7. Embryogenesis and Larval Biology of the Cold-Water Coral Lophelia pertusa

    PubMed Central

    Strömberg, Susanna M.; Dahl, Mikael P.; Lundälv, Tomas; Brooke, Sandra

    2014-01-01

    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. PMID:25028936

  8. 3D Light-Sheet Fluorescence Microscopy of Cranial Neurons and Vasculature during Zebrafish Embryogenesis.

    PubMed

    Park, Ok Kyu; Kwak, Jina; Jung, Yoo Jung; Kim, Young Ho; Hong, Hyun-Seok; Hwang, Byung Joon; Kwon, Seung-Hae; Kee, Yun

    2015-11-30

    Precise 3D spatial mapping of cells and their connections within living tissues is required to fully understand developmental processes and neural activities. Zebrafish embryos are relatively small and optically transparent, making them the vertebrate model of choice for live in vivo imaging. However, embryonic brains cannot be imaged in their entirety by confocal or two-photon microscopy due to limitations in optical range and scanning speed. Here, we use light-sheet fluorescence microscopy to overcome these limitations and image the entire head of live transgenic zebrafish embryos. We simultaneously imaged cranial neurons and blood vessels during embryogenesis, generating comprehensive 3D maps that provide insight into the coordinated morphogenesis of the nervous system and vasculature during early development. In addition, blood cells circulating through the entire head, vagal and cardiac vasculature were also visualized at high resolution in a 3D movie. These data provide the foundation for the construction of a complete 4D atlas of zebrafish embryogenesis and neural activity. PMID:26429501

  9. Dynamics of enhancer chromatin signatures mark the transition from pluripotency to cell specification during embryogenesis

    PubMed Central

    Bogdanovi?, Ozren; Fernandez-Miñán, Ana; Tena, Juan J.; de la Calle-Mustienes, Elisa; Hidalgo, Carmen; van Kruysbergen, Ila; van Heeringen, Simon J.; Veenstra, Gert Jan C.; Gómez-Skarmeta, José Luis

    2012-01-01

    The generation of distinctive cell types that form different tissues and organs requires precise, temporal and spatial control of gene expression. This depends on specific cis-regulatory elements distributed in the noncoding DNA surrounding their target genes. Studies performed on mammalian embryonic stem cells and Drosophila embryos suggest that active enhancers form part of a defined chromatin landscape marked by histone H3 lysine 4 mono-methylation (H3K4me1) and histone H3 lysine 27 acetylation (H3K27ac). Nevertheless, little is known about the dynamics and the potential roles of these marks during vertebrate embryogenesis. Here, we provide genomic maps of H3K4me1/me3 and H3K27ac at four developmental time-points of zebrafish embryogenesis and analyze embryonic enhancer activity. We find that (1) changes in H3K27ac enrichment at enhancers accompany the shift from pluripotency to tissue-specific gene expression, (2) in early embryos, the peaks of H3K27ac enrichment are bound by pluripotent factors such as Nanog, and (3) the degree of evolutionary conservation is higher for enhancers that become marked by H3K27ac at the end of gastrulation, suggesting their implication in the establishment of the most conserved (phylotypic) transcriptome that is known to occur later at the pharyngula stage. PMID:22593555

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

    PubMed

    Larsson, Ann I; Järnegren, Johanna; Strömberg, Susanna M; Dahl, Mikael P; Lundälv, Tomas; Brooke, Sandra

    2014-01-01

    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. PMID:25028936

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

    NASA Technical Reports Server (NTRS)

    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.

  12. Mind-Body Interactions in Anxiety and Somatic Symptoms.

    PubMed

    Mallorquí-Bagué, Núria; Bulbena, Antonio; Pailhez, Guillem; Garfinkel, Sarah N; Critchley, Hugo D

    2016-01-01

    Anxiety and somatic symptoms have a high prevalence in the general population. A mechanistic understanding of how different factors contribute to the development and maintenance of these symptoms, which are highly associated with anxiety disorders, is crucial to optimize treatments. In this article, we review recent literature on this topic and present a redefined model of mind-body interaction in anxiety and somatic symptoms, with an emphasis on both bottom-up and top-down processes. Consideration is given to the role played in this interaction by predisposing physiological and psychological traits (e.g., interoception, anxiety sensitivity, and trait anxiety) and to the levels at which mindfulness approaches may exert a therapeutic benefit. The proposed model of mind-body interaction in anxiety and somatic symptoms is appraised in the context of joint hypermobility syndrome, a constitutional variant associated with autonomic abnormalities and vulnerability to anxiety disorders. PMID:26713718

  13. The Great Recession, somatic symptomatology and alcohol use and abuse.

    PubMed

    Vijayasiri, Ganga; Richman, Judith A; Rospenda, Kathleen M

    2012-09-01

    While most research has examined the long-term effects of alcohol consumption on health, the current study examines how health status impacts on drinking behavior. Using data from a national study conducted between 2010 and 2011 to assess the impact of the recession on drinking behavior, this study examines how economic hardships linked to the recent economic recession affect physical health, and how physical health may in turn affect alcohol use. Structural equation models were used to test the predicted associations. The data demonstrate that many of the economic stressors linked to the recession are associated with increased somatic symptoms. Somatic symptoms are also associated with increased drinking for men, but not for women. These findings suggest that men may use alcohol to self medicate somatic symptomatology. The current findings are consistent with gender role-based explanations that account for gender disparities in the utilization of medical care. PMID:22632797

  14. [Psychiatric illness does not protect against a somatic disease].

    PubMed

    Mulder, T; de Reus, R

    2001-07-14

    In four patients, two women aged 68 and 73 years and two men aged 65 and 57 years, serious diseases were not recognised because of more prominent psychiatric symptoms. Three of the patients had malignancies and one was suffering from dehydration with a urinary tract infection and de novo diabetes mellitus. The patient with a meningioma recovered after surgery, the other three patients died despite treatment. Somatic diseases may not be recognised in patients with psychiatric illness because doctors may be more likely to ascribe the symptoms to a psychiatric cause. Patients may also present their symptoms in an unusual way. It is important not only to diagnose the psychiatric disease but also to check the patient's physical condition. This applies particularly to elderly patients, because they are more likely to have somatic diseases. Good education of psychiatrists in terms of somatic diseases remains important. PMID:11484427

  15. The recent history of somatic cloning in mammals.

    PubMed

    Brem, Gottfried; Kühholzer, Birgit

    2002-01-01

    The history of somatic cell nuclear transfer (NT) in mammals is full of exciting experiments and findings regarding the technique and outcome of NT, despite only covering a period of 6 years. The production of Dolly, for the first time demonstrating cloning from an adult somatic cell, had a great impact on subsequent studies. However, the more progress we make, the more obvious it becomes how little we know about the processes during NT, specifically how reprogramming events occur. Therefore, it is certainly challenging to continue investigating every step of somatic cell NT more intensively, starting from the donor cell, (type, cell cycle, synchronization, population doublings) and continuing until the cloned offspring are born and even further, to see how and if NT has an influence on health, viability, quantitative traits, and reproduction of cloned individuals. PMID:12006157

  16. From Somatic Cells to Oocytes: A Novel Yolk Protein Produced by Ovarian Somatic Cells in a Stony Coral, Euphyllia ancora.

    PubMed

    Shikina, Shinya; Chiu, Yi-Ling; Lee, Yan-Horn; Chang, Ching-Fong

    2015-09-01

    To gain a better understanding of how corals form their eggs at both the molecular and cellular levels, we performed a differential screen (suppression subtractive hybridization) to identify genes related to oocyte development in a stony coral, Euphyllia ancora. Through the course of screening, a novel gene that contains three alternate repeats of fibronectin domain 2 and epidermal growth factor (EGF)-like domains, as well as an additional calcium-binding EGF-like domain (EGF-CA), was identified and tentatively named euphy after the scientific name of the coral, E. ancora. Quantitative RT-PCR revealed that expression levels of euphy increased in female colonies as the coral approached reproductive season. Tissue distribution analysis followed by mRNA in situ hybridization revealed that euphy is highly expressed in the ovarian (mesenterial) somatic cells in the body of E. ancora. Staining of tissue sections with an antibody against euphy protein (Euphy) revealed Euphy immunoreactivity in both ovarian somatic cells and oocytes. Subsequent Western blotting demonstrated the presence of abundant Euphy in unfertilized mature eggs. These results indicate that Euphy produced in the ovarian somatic cells is transported to and accumulates within oocytes as a yolk protein during oogenesis. We previously showed that two major yolk proteins, vitellogenin and egg protein, are similarly produced by ovarian somatic cells. Hence, the present study uncovered the third ovarian somatic-derived yolk protein in corals. Our data provide new information that contributes to a more comprehensive understanding of coral egg formation. PMID:26178717

  17. Functional Evaluation of ES–Somatic Cell Hybrids In Vitro and In Vivo

    PubMed Central

    Kim, Kitai; Liu, Jun; Ng, Kitwa; Daley, George Q.; Verma, Paul J.

    2014-01-01

    Abstract Embryonic stem cells (ESCs) have previously been reported to reprogram somatic cells following fusion. The resulting ES–somatic cell hybrids have been shown to adopt the transcriptional profile of ESCs, suggesting that the pluripotent program is dominant. ES–somatic cell hybrids have most characteristics of pluripotent cells in vitro; however, it remains unclear whether the somatic genome is an active partner in the hybrid cells or simply retained predominately as silent cargo. Furthermore, the functional properties of ES–somatic cell hybrids in vivo have been limited to studies on their contribution to teratomas and developing embryos/chimeras. The extent of their pluripotency remains largely unclear. Here we determined that the somatic genome is actively transcribed by generating ES–somatic cell hybrids using Rag2-deficient ESCs fused to autologous wild-type somatic cells. Rag2 expression was detected during in vitro differentiation, suggesting that the somatic genome follows the correct temporal cues during differentiation. Furthermore, ES–somatic cell hybrids maintain their tetraploid state following 4 weeks of differentiation in vivo and are immune tolerated when transferred into matched individuals. The ES–somatic cell hybrids can efficiently differentiate into hematopoietic precursors in both myeloid and lymphoid lineages in vitro, suggesting that the somatic genome is actively transcribed following cell fusion based reprogramming. However, the ES–somatic cell hybrids showed an altered hematopoietic potential following in vitro differentiation and were unable to show hematopoietic engraftment in a mouse model. PMID:24787484

  18. Analysis of glucocorticoid-resistant human leukemic cells by somatic cell hybridization.

    PubMed

    Harmon, J M; Thompson, E B; Baione, K A

    1985-04-01

    Glucocorticoid-resistant mutants isolated form the glucocorticoid-sensitive human leukemic cell line CEM-C7 can be divided into three phenotypes: those with almost no glucocorticoid-binding activity (r-); those whose steroid-receptor complexes are unstable during attempted activation but are stabilized by the presence of sodium molybdate (actl:molybdate-sensitive); and those whose steroid-receptor complexes are unstable during attempted activation but are insensitive to the presence of molybdate (actl:molybdate-resistant). To determine if these phenotypes represent different mutations within the glucocorticoid receptor locus itself or reflect alterations in other components modifying receptor function, somatic hybrids were constructed between wild-type cells and all three classes of resistant mutants, as well as between various classes of resistant mutants. Hybrids were analyzed for chromosome content, steroid-induced growth inhibition, induction of the enzyme glutamine synthetase, and glucocorticoid receptor content. Hybrids constructed between wild-type cells and any of the three classes of resistant cells were growth-inhibited in the presence of dexamethasone, displayed normal levels of glutamine synthetase induction, and contained a quantity of glucocorticoid receptor approximately equal to the sum of the glucocorticoid receptor concentrations of the parental cell lines. Hybrids constructed between various classes of resistant cells were not growth-inhibited by dexamethasone, displayed no glutamine synthetase induction, and also contained the sum of the glucocorticoid receptor concentration of the individual parents. Thus, each phenotype is recessive, and there is no complementation between phenotypes. We conclude that the three phenotypes are the result of different mutations within the glucocorticoid receptor locus itself and do not represent the presence of dominant receptor-inactivating factors or the absence of positive regulatory components. PMID:2858265

  19. Botulinum toxin for the treatment of somatic tinnitus.

    PubMed

    Láinez, Miguel J A; Piera, Anna

    2007-01-01

    Subjective tinnitus is an auditory sensation experienced in the absence of external or internal acoustic stimuli. It causes significant morbidity and can progress to a chronic debilitating condition. Somatic tinnitus is tinnitus that can be modulated by stimulation of the somatic sensory system. It occurs because of interactions between the auditory and the somatosensory system that may occur at several levels of the central nervous system. In the present chapter, we discuss how botulinum toxin can improve tinnitus and discuss the mechanism of its action, and how it relates to its effects on chronic pain. PMID:17956797

  20. Somatic-cell mutation induced by short exposures to cigarette smoke in urate-null, oxidative stress-sensitive Drosophila.

    PubMed

    Uchiyama, Tomoyo; Koike, Ryota; Yuma, Yoko; Okamoto, Keinosuke; Arimoto-Kobayashi, Sakae; Suzuki, Toshinori; Negishi, Tomoe

    2016-01-01

    We previously reported that a urate-null strain of Drosophila is hypersensitive to cigarette smoke (CS), and we suggested that CS induces oxidative stress in Drosophila because uric acid is a potent antioxidant. Although the carcinogenic risk of CS exposure is widely recognized; documentation of in vivo genotoxic activity of environmental CS, especially gaseous-phase CS, remains inconclusive. To date, somatic-cell mutations in Drosophila resulting from exposure to CS have not been detected via the somatic mutation and recombination test (wing spot test) with wild-type flies, a widely used Drosophila assay for the detection of somatic-cell mutation; moreover, genotoxicity has not been documented via a DNA repair test that involves DNA repair-deficient Drosophila. In this study, we used a new Drosophila strain (y v ma-l; mwh) to examine the mutagenicity induced by gaseous-phase CS; these flies are urate-null due to a mutation in ma-l, and they are heterozygous for multiple wing hair (mwh), a mutation that functions as a marker for somatic-cell mutation. In an assay with this newly developed strain, a superoxide anion-producing weed-killer, paraquat, exhibited significant mutagenicity; in contrast, paraquat was hardly mutagenic with a wild-type strain. Drosophila larvae were exposed to CS for 2, 4 or 6h, and then kept at 25°C on instant medium until adulthood. After eclosion, mutant spots, which consisted of mutant hairs on wings, were scored. The number of mutant spots increased significantly in an exposure time-dependent manner in the urate-null females (ma-l (-/-)), but not in the urate-positive females (ma-l (+/-)). In this study, we showed that short-term exposure to CS was mutagenic in this in vivo system. In addition, we obtained suggestive data regarding reactive oxygen species production in larva after CS exposure using the fluorescence probe H2DCFDA. These results suggest that oxidative damage, which might be countered by uric acid, was partly responsible for induction of somatic cell mutations in Drosophila larvae exposed to CS. PMID:26138228

  1. Genotoxic effects of two-generational selenium deficiency in mouse somatic and testicular cells.

    PubMed

    Graupner, Anne; Instanes, Christine; Andersen, Jill M; Brandt-Kjelsen, Anicke; Dertinger, Stephen D; Salbu, Brit; Brunborg, Gunnar; Olsen, Ann-Karin

    2015-03-01

    Many studies have investigated genotoxic effects of high Se diets but very few have addressed the genotoxicity of Se deprivation and its consequences in germ cells and none in somatic cells. To address these data gaps, C57BL/6 male mice were subjected to Se deprivation starting in the parental generation, i.e. before conception. Mice were given a diet of either low (0.01mg Se/kg diet) or normal (0.23mg Se/kg diet) Se content. Ogg1-deficient (Ogg1 (-/-) ) mice were used as a sensitive model towards oxidative stress due to their reduced capacity to repair oxidised purines. Ogg1 (-/-) mice also mimic the repair characteristics of human post-meiotic male germ cells which have a reduced ability to repair such lesions. The genotoxicity of Se deficiency was addressed by measuring DNA lesions with the alkaline single cell gel electrophoresis (+ Fpg to detect oxidised DNA lesions) in somatic cells (nucleated blood cells and lung cells) and male germ cells (testicular cells). Total Se concentration in liver and GPx activity in plasma and testicular cells were measured. Gene mutation was evaluated by an erythrocyte-based Pig-a assay. We found that Se deprivation of F1 from their conception and until early adulthood led to the induction of DNA lesions in testicular and lung cells expressed as significantly increased levels of DNA lesions, irrespective of the mouse genotype. In blood cells, Se levels did not appear to affect DNA lesions or mutant cell frequencies. The results suggest that the testis was the most sensitive tissue. Thus, genotoxicity induced by the low Se diet in the spermatozoal genome has potential implications for the offspring. PMID:25358475

  2. Induction tool resolution

    SciTech Connect

    Zhou, Q.; Beard, D.; Hilliker, D.J.

    1994-12-31

    The economics of oil production today require more accurate estimates of the saturation and movability of hydrocarbons in relatively thin formation structures. The advent of array type induction sondes in petroleum well logging increases the information available. However, the ability to resolve thin beds in a complex borehole environment is defined by the physics of the induction method. The information content measured by a hypothetical induction array having all coil spacings is analyzed, and a quantitative expression for the decrease in vertical resolution with radial depth is derived. The pseudo 2-D model used has conductivity variation in the z-direction on a cylindrical shell centered about the tool axis. The radial dependence of the vertical resolution is examined by varying the radius of the cylindrical shell. For brevity in mathematical expressions, a two-coil induction tool is considered as a basic unit. Combinations of the basic unit are studied to quantify the resolution limit and facilitate the induction tool design.

  3. The Spectra of Somatic Mutations Across Many Tumor Types - Michael Lawrence, TCGA Scientific Symposium 2011

    Cancer.gov

    Home News and Events Multimedia Library Videos The Spectra of Somatic Mutations Across Many Tumor Types - Michael Lawrence The Spectra of Somatic Mutations Across Many Tumor Types - Michael Lawrence, TCGA Scientific Symposium 2011 You will need Adobe

  4. Comparison and Validation of Somatic Mutation Callers - Andrey Sivachenko, TCGA Scientific Symposium 2011

    Cancer.gov

    Home News and Events Multimedia Library Videos Comparison and Validation of Somatic Mutation Callers - Andrey Sivachenko Comparison and Validation of Somatic Mutation Callers - Andrey Sivachenko, TCGA Scientific Symposium 2011 You will need Adobe

  5. Somatic complaints in older adults: aging process or symptoms of depression 

    E-print Network

    Gentry, Ruth Anne

    2013-02-22

    This study examined the efficacy of somatic symptoms on a new measure of depression designed specifically for older adults. Resent research has shown somatic symptoms to be accurate predictors of depression in older adults, yet they have been...

  6. The Landscape of Somatic Structural Rearrangements in RAS Pathway Genes - Angeliki Pantazi, TCGA Scientific Symposium 2015

    Cancer.gov

    Home News and Events Multimedia Library Videos The Landscape of Somatic Structural Rearrangements in RAS Pathway Genes - Angeliki Pantazi, TCGA The Landscape of Somatic Structural Rearrangements in RAS Pathway Genes - Angeliki Pantazi, TCGA Scientific

  7. The Somatic Genomic Landscape of Glioblastoma Multiforme - Roel Verhaak, TCGA Scientific Symposium 2012

    Cancer.gov

    Home News and Events Multimedia Library Videos The Somatic Genomic Landscape of Glioblastoma Multiforme - Roel Verhaak The Somatic Genomic Landscape of Glioblastoma Multiforme - Roel Verhaak, TCGA Scientific Symposium 2012 You will need Adobe Flash

  8. Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter, TCGA Scientific Symposium 2011

    Cancer.gov

    Home News and Events Multimedia Library Videos Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter, TCGA Scientific Symposium 2011 You

  9. Analysis of Somatic Mutations Across Many Tumor Types - Petar Stojanov, TCGA Scientific Symposium 2012

    Cancer.gov

    Home News and Events Multimedia Library Videos Analysis of Somatic Mutations Across Many Tumor Types - Petar Stojanov Analysis of Somatic Mutations Across Many Tumor Types - Petar Stojanov, TCGA Scientific Symposium 2012 You will need Adobe Flash

  10. Somatic Copy Number Alterations and Aneuploidy Events in Uveal Melanoma- Juliann Shih, TCGA Scientific Symposium 2015

    Cancer.gov

    Home News and Events Multimedia Library Videos Somatic Copy Number Alterations and Aneuploidy Events in Uveal Melanoma- Juliann Shih, TCGA 2015 Somatic Copy Number Alterations and Aneuploidy Events in Uveal Melanoma- Juliann Shih, TCGA Scientific

  11. Calibrating and adjusting expectations in life: A grounded theory on how elderly persons with somatic health problems maintain control and balance in life and optimize well-being

    PubMed Central

    Helvik, Anne-Sofie; Iversen, Valentina Cabral; Steiring, Randi; Hallberg, Lillemor R-M

    2011-01-01

    Aim This study aims at exploring the main concern for elderly individuals with somatic health problems and what they do to manage this. Method In total, 14 individuals (mean=74.2 years; range=68–86 years) of both gender including hospitalized and outpatient persons participated in the study. Open interviews were conducted and analyzed according to grounded theory, an inductive theory-generating method. Results The main concern for the elderly individuals with somatic health problems was identified as their striving to maintain control and balance in life. The analysis ended up in a substantive theory explaining how elderly individuals with somatic disease were calibrating and adjusting their expectations in life in order to adapt to their reduced energy level, health problems, and aging. By adjusting the expectations to their actual abilities, the elderly can maintain a sense of that they still have the control over their lives and create stability. The ongoing adjustment process is facilitated by different strategies and result despite lower expectations in subjective well-being. The facilitating strategies are utilizing the network of important others, enjoying cultural heritage, being occupied with interests, having a mission to fulfill, improving the situation by limiting boundaries and, finally, creating meaning in everyday life. Conclusion The main concern of the elderly with somatic health problems was to maintain control and balance in life. The emerging theory explains how elderly people with somatic health problems calibrate their expectations of life in order to adjust to reduced energy, health problems, and aging. This process is facilitated by different strategies and result despite lower expectation in subjective well-being. PMID:21468299

  12. Expression of the Ku70 subunit (XRCC6) and protection from low dose ionizing radiation during zebrafish embryogenesis.

    PubMed

    Bladen, Catherine L; Navarre, Sammy; Dynan, William S; Kozlowski, David J

    2007-07-11

    The Ku70 protein, a product of the XRCC6 gene, is a component of the nonhomologous end-joining (NHEJ) pathway of DNA repair, which protects cells from the effects of radiation-induced DNA damage. Although the spatial expression of Ku70 during vertebrate embryogenesis has not been described, DNA repair proteins are generally considered to be "housekeeping" genes, which are required for radioprotection in all cells. Here, we report the cloning and characterization of the zebrafish Ku70 ortholog. In situ hybridization and RT-PCR analyses demonstrate that Ku70 mRNA is maternally provided and expressed uniformly among embryonic blastomeres. Later during embryogenesis, zygotically transcribed Ku70 mRNA specifically accumulates in neural tissue, including the retina and proliferative regions of the developing brain. In the absence of genotoxic stress, morpholino-mediated knockdown of Ku70 expression does not affect zebrafish embryogenesis. However, exposure of Ku70 morpholino-injected embryos to low doses of ionizing radiation leads to marked cell death throughout the developing brain, spinal cord, and tail. These results suggest that Ku70 protein plays a crucial role in protecting the developing nervous system from radiation-induced DNA damage during embryogenesis. PMID:17630212

  13. Quantitative and ultrastructural analysis of the chondriome in ovogenesis and embryogenesis of the sea urchin Paracentrotus lividus. 2. Growth and proliferation of mitochondria in embryogenesis.

    PubMed

    Sukhomlinova MYu; Kireyev, I I; Fais, D; Giudice, G; Polyakov VYu

    2001-07-01

    The dynamics of structural changes of the chondriome in the early development of the sea urchin Paracentrotus lividus was studied. Mature eggs and embryos at various stages of cleavage were used for quantitative and ultrastructural analysis based on computerized 3D reconstruction from serial ultrathin sections. The following structural transformations of the chondriome were shown to occur in the course of embryogenesis: (i) 15 min after fertilization, mitochondrial clusters disintegrate, and mitochondrial division is induced. At the stage of two blastomeres the population of mitochondria increases twofold; (ii) the mitochondria divide by means of the contraction of both outer and inner membranes. The forming furrow divides the "parental" mitochondrion into two equal "daughter" parts; (iii) at the four-cell stage the division ceases, and mitochondria start to grow, so that the mitochondrial length increases; (iv) cell differentiation further stimulates elongation of rod-shaped mitochondria, and the ratio of rod-shaped to spherical mitochondria changes; (v) in an unfertilised egg, the mitochondria are in a condensed form; after fertilisation all the mitochondria acquire a conventional form. Modern concepts of chondriome proliferation in eukaryotic cells are discussed. PMID:11699864

  14. SOMATIC CELL COUNTS OF MILK FROM DAIRY HERD IMPROVEMENT HERDS DURING 2005

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2005 were examined to assess the status of national milk quality. Cows with records failing AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to somat...

  15. Reprogramming of murine and human somatic cells using a single polycistronic vector

    E-print Network

    Saha, Krishanu

    concerns associated with somatic cell nuclear transfer (SCNT) and human embryonic stem (hES) cellsReprogramming of murine and human somatic cells using a single polycistronic vector Bryce W. Careya, 2008) Directed reprogramming of somatic cells by defined factors pro- vides a novel method

  16. Genetic and somatic effects in animals maintained on tritiated water

    SciTech Connect

    Carsten, A.L.; Brooks, A.; Commerford, S.L.; Cronkite, E.P.

    1981-01-01

    The possible genetic (dominant lethal mutations (DLM) and cytogenetic changes in the regenerating liver) and somatic (hematopoietic stem cell changes, growth and nonspecific life time shortening) effects in mice maintained on tritiated water (HTO) over two generations was investigated. Results to date are summarized. (ACR)

  17. The histone chaperone CAF-1 safeguards somatic cell identity.

    PubMed

    Cheloufi, Sihem; Elling, Ulrich; Hopfgartner, Barbara; Jung, Youngsook L; Murn, Jernej; Ninova, Maria; Hubmann, Maria; Badeaux, Aimee I; Euong Ang, Cheen; Tenen, Danielle; Wesche, Daniel J; Abazova, Nadezhda; Hogue, Max; Tasdemir, Nilgun; Brumbaugh, Justin; Rathert, Philipp; Jude, Julian; Ferrari, Francesco; Blanco, Andres; Fellner, Michaela; Wenzel, Daniel; Zinner, Marietta; Vidal, Simon E; Bell, Oliver; Stadtfeld, Matthias; Chang, Howard Y; Almouzni, Genevieve; Lowe, Scott W; Rinn, John; Wernig, Marius; Aravin, Alexei; Shi, Yang; Park, Peter J; Penninger, Josef M; Zuber, Johannes; Hochedlinger, Konrad

    2015-12-01

    Cellular differentiation involves profound remodelling of chromatic landscapes, yet the mechanisms by which somatic cell identity is subsequently maintained remain incompletely understood. To further elucidate regulatory pathways that safeguard the somatic state, we performed two comprehensive RNA interference (RNAi) screens targeting chromatin factors during transcription-factor-mediated reprogramming of mouse fibroblasts to induced pluripotent stem cells (iPS cells). Subunits of the chromatin assembly factor-1 (CAF-1) complex, including Chaf1a and Chaf1b, emerged as the most prominent hits from both screens, followed by modulators of lysine sumoylation and heterochromatin maintenance. Optimal modulation of both CAF-1 and transcription factor levels increased reprogramming efficiency by several orders of magnitude and facilitated iPS cell formation in as little as 4 days. Mechanistically, CAF-1 suppression led to a more accessible chromatin structure at enhancer elements early during reprogramming. These changes were accompanied by a decrease in somatic heterochromatin domains, increased binding of Sox2 to pluripotency-specific targets and activation of associated genes. Notably, suppression of CAF-1 also enhanced the direct conversion of B cells into macrophages and fibroblasts into neurons. Together, our findings reveal the histone chaperone CAF-1 to be a novel regulator of somatic cell identity during transcription-factor-induced cell-fate transitions and provide a potential strategy to modulate cellular plasticity in a regenerative setting. PMID:26659182

  18. A mathematical framework to determine the temporal sequence of somatic

    E-print Network

    at unprecedented throughput and resolution (1­3). Computational algorithms designed to filter random genetic events transformed stage (Fig. 1). Model RESIC is based on the principles of population genetics--the mathematicalA mathematical framework to determine the temporal sequence of somatic genetic events in cancer

  19. Somatic deletions implicated in functional diversity of brain cells of

    E-print Network

    Lee, Doheon

    of chromosome 1, 18 and X in the brain of individuals with schizophrenia and a somatic mutation in AKT3 has been may occur in the same zygote8 . Numerous neuropathological abnormalities have been described with schizophrenia as compared to unaffected controls. Furthermore, these abnormalities have been associated

  20. Genetics of Somatic Fusion in PHYSARUM POLYCEPHALUM: the Ppii Strain

    PubMed Central

    Collins, O'Neil Ray; Haskins, Edward F.

    1972-01-01

    Plasmodial (somatic) fusion in a strain of Physarum polycephalum, a true slime mold, is controlled by four loci, each of which displays simple dominance. Two diploid plasmodia fuse with each other only if they are phenotypically or genotypically identical for all four fusion loci. PMID:17248576

  1. BRIEF COMMUNICATION Somatic INK4a-ARF Locus Mutations

    E-print Network

    Tsai, Ming-Daw

    BRIEF COMMUNICATION Somatic INK4a-ARF Locus Mutations: A Signi®cant Mechanism of Gene Inactivation, Columbus, Ohio The INK4a-ARF locus is located on human chromosome 9p21 and is known to encode two functionally distinct tumor-suppressor genes. The p16INK4a (p16) tumor-suppressor gene product is a negative

  2. Research Focus The Iowa Gambling Task and the somatic marker

    E-print Network

    McClelland, James L. "Jay"

    Research Focus The Iowa Gambling Task and the somatic marker hypothesis: some questions and answersClelland on participants' knowledge in the Iowa Gambling Task suggests a different interpretation for an experiment we]. The development of the Iowa Gambling Task (IGT) offered further experi- mental support for the SMH, in ours [2

  3. More Frequent than Desired: Midgut Stem Cell Somatic Mutations.

    PubMed

    Li, Qi; Ip, Y Tony

    2015-12-01

    The accumulation of somatic mutations in adult stem cells contributes to the decline of tissue functions and cancer initiation. In this issue of Cell Stem Cell, Siudeja et al. (2015) investigate the rate and mechanism of naturally occurring mutations in Drosophila midgut intestinal stem cells during aging and find high-frequency mutations arising from multiple mechanisms. PMID:26637937

  4. ORIGINAL PAPER Regeneration and plantlet development from somatic tissues

    E-print Network

    dePamphilis, Claude

    ORIGINAL PAPER Regeneration and plantlet development from somatic tissues of Aristolochia fimbriata, rooting, and acclimation of tissue culture- derived plants. Two varieties of Aristolochia were multi- plied in vitro and rooted with 100% efficiency. Shoot regeneration was achieved within 1 month

  5. DOES FAMILY OF ORIGIN FUNCTIONING PREDICT ADULT SOMATIC COMPLAINTS?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    It has long been believed that adult somatic complaints are associated with early family dysfunction. Yet few studies have examined this hypothesis in community samples, where medically unexplained symptom complaints are estimated to be very common. Given the potential population-wide impact of subt...

  6. Reshaping the Transcriptional Frontier: Epigenetics and Somatic Cell Nuclear Transfer

    PubMed Central

    LONG, CHARLES R.; WESTHUSIN, MARK E.; GOLDING, MICHAEL C.

    2014-01-01

    SUMMARY Somatic-cell nuclear transfer (SCNT) experiments have paved the way to the field of cellular reprogramming. The demonstrated ability to clone over 20 different species to date has proven that the technology is robust but very inefficient, and is prone to developmental anomalies. Yet, the offspring from cloned animals exhibit none of the abnormalities of their parents, suggesting the low efficiency and high developmental mortality are epigenetic in origin. The epigenetic barriers to reprogramming somatic cells into a totipotent embryo capable of developing into a viable offspring are significant and varied. Despite their intimate relationship, chromatin structure and transcription are often not uniformly reprogramed after nuclear transfer, and many cloned embryos develop gene expression profiles that are hybrids between the donor cell and an embryonic blastomere. Recent advances in cellular reprogramming suggest that alteration of donor-cell chromatin structure towards that found in an normal embryo is actually the rate-limiting step in successful development of SCNT embryos. Here we review the literature relevant to the transformation of a somatic-cell nucleus into an embryo capable of full-term development. Interestingly, while resetting somatic transcription and associated epigenetic marks are absolutely required for development of SCNT embryos, life does not demand perfection. PMID:24167064

  7. Somatic Attractiveness: As in Other Things, Moderation is Best.

    ERIC Educational Resources Information Center

    Freeman, Harvey R.

    1985-01-01

    Investigated whether a physical attractiveness stereotype exists when "attractive" is defined in terms of physique and "positive" is defined in terms of sex role characteristics and future life happiness. Sex role and life happiness were rated highest for those of intermediate attractiveness. Results for somatic beauty are discussed. (Author/BL)

  8. Somatic, Affective and Behavioral Distress Reactions across Cultures

    ERIC Educational Resources Information Center

    Canel-Cinarbas, Deniz; Aegisdottir, Stefania

    2010-01-01

    The purpose of the present study was to compare the expression and frequency of somatic, affective and cognitive symptoms of distress across Turkish and U.S. university students. An open-ended free-list question was used to elicit distress responses from 827 Turkish and U.S. participants. The coding was done using classical content analysis. It…

  9. Somatic Symptoms in Children and Adolescents with Anxiety Disorders

    ERIC Educational Resources Information Center

    Ginsburg, Golda S.; Riddle, Mark A.; Davies, Mark

    2006-01-01

    Objective: To evaluate the prevalence of somatic symptoms (SSs) in children and adolescents with anxiety disorders; the relationship between SSs and anxiety severity, impairment, and child global functioning; and the impact of fluvoxamine (FLV) versus pill placebo (PBO) on reducing SSs. Method: As part of a double-blind, placebo-controlled trial,…

  10. Somatic Mosaicism in Cases with Small Supernumerary Marker Chromosomes

    PubMed Central

    Liehr, Thomas; Karamysheva, Tatyana; Merkas, Martina; Brecevic, Lukrecija; Hamid, Ahmed B.; Ewers, Elisabeth; Mrasek, Kristin; Kosyakova, Nadezda; Weise, Anja

    2010-01-01

    Somatic mosaicism is something that is observed in everyday lives of cytogeneticists. Chromosome instability is one of the leading causes of large-scale genome variation analyzable since the correct human chromosome number was established in 1956. Somatic mosaicism is also a well-known fact to be present in cases with small supernumerary marker chromosomes (sSMC), i.e. karyotypes of 47,+mar/46. In this study, the data available in the literature were collected concerning the frequency mosaicism in different subgroups of patients with sSMC. Of 3124 cases with sSMC 1626 (52%) present with somatic mosaicism. Some groups like patients with Emanuel-, cat-eye- or i(18p)- syndrome only tend rarely to develop mosaicism, while in Pallister-Killian syndrome every patient is mosaic. In general, acrocentric and non-acrocentric derived sSMCs are differently susceptible to mosaicism; non-acrocentric derived ones are hereby the less stable ones. Even though, in the overwhelming majority of the cases, somatic mosaicism does not have any detectable clinical effects, there are rare cases with altered clinical outcomes due to mosaicism. This is extremely important for prenatal genetic counseling. Overall, as mosaicism is something to be considered in at least every second sSMC case, array-CGH studies cannot be offered as a screening test to reliably detect this kind of chromosomal aberration, as low level mosaic cases and cryptic mosaics are missed by that. PMID:21358988

  11. Somatic gene therapy. Present situation and future perspective.

    PubMed

    Gottschalk, U; Chan, S

    1998-11-01

    The ultimate goal in the management of inherited as well as acquired diseases is a rational therapy with the aim to eliminate the underlying biochemical defects, rather than a symptomatic treatment. Among other approaches somatic gene therapy is a promising candidate to meet these objectives and appears to have the potential to revolutionize modern medicine. Gene therapy is characterized by the transfer of genetic information to a patient through the use of recombinant DNA technology. Several strategies for the treatment of monogenetic disorders as well as chronical diseases like cancer and AIDS have been used in various somatic gene therapy projects. So far, 329 clinical studies (phases I, I/II and II) with over 2500 patients have been initiated worldwide since 1989. No significant toxicity and adverse side effects have been observed. To allow efficient transfer of the therapeutic genes, a variety of gene delivery techniques have been developed based on viral and non-viral vector systems. For the success of this technology it is vital to achieve regulated and sustained expression of foreign genes in specific target tissues. This will be crucial for the widespread application of somatic gene therapy. So far none for the gene delivery systems is able to meet the requirements of safety, efficiency and specificity demonstrating that vector research will be an important focus in the development of optimized transfer methods. From a regulatory point of view pharmaceutical DNA-products can be regarded as drugs and are therefore subject to the same regulations. Human gene therapy must, however, be limited to manipulations affecting somatic, differentiated cells to prevent the transferred gene from being transmitted to the individual's descendants. Applications for the purpose of 'enhancement' and not for the treatment of diseases are also not acceptable. Under these prerequisites, somatic gene therapy does not raise any new ethical concerns and can be interpreted as a special form of an organ transplantation. A comparison of the different regulatory situations of gene therapy in Europe and the United States demonstrates that for the European countries a uniform regulation is desired. Today somatic gene therapy is still in its infancy. It will continue to be scientifically and technically challenging until simple and effective procedures will have been developed. Demonstration of its clinical efficacy especially in the long term will have to be the next step. Looking at the history of biotechnology and the success of the biotechnology industry that is now providing safe and efficient products from recombinant DNA-technology there is little doubt that gene therapy will become a successful treatment for various indications in the next decade. The purpose of this article is to review the current status of the development in somatic gene therapy. PMID:9850435

  12. Direct reading inductance meter

    NASA Technical Reports Server (NTRS)

    Kolby, R. B. (inventor)

    1977-01-01

    A direct reading inductance meter comprised of a crystal oscillator and an LC tuned oscillator is presented. The oscillators function respectively to generate a reference frequency, f(r), and to generate an initial frequency, f(0), which when mixed produce a difference equal to zero. Upon connecting an inductor of small unknown value in the LC circuit to change its resonant frequency to f(x), a difference frequency (f(r)-f(x)) is produced that is very nearly a linear function of the inductance of the inductor. The difference frequency is measured and displayed on a linear scale in units of inductance.

  13. The induction motor

    NASA Astrophysics Data System (ADS)

    Redinz, José Arnaldo

    2015-09-01

    We obtain analytical expressions for the torques and angular speed of an induction motor with a simple geometry, resembling the geometry of the first induction motor investigated by Arago in 1824. The rotor is a conducting disc rotating between the magnetic poles of two off-axis solenoids, displaced in space by 90^\\circ from each other. We apply our results to discuss a theory for the ubiquitous electromechanical watt-hour meter. For comparison of the theoretical result for the angular speed with measurements, we propose a simple experiment in which an induction motor with an aluminum disc rotor is constructed.

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

    PubMed

    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. PMID:26619882

  15. Characterization of two novel small molecules targeting melanocyte development in zebrafish embryogenesis.

    PubMed

    Chen, Lu; Ren, Xi; Liang, Fang; Li, Song; Zhong, Hanbing; Lin, Shuo

    2012-07-01

    Melanocytes are pigment cells that are closely associated with many skin disorders, such as vitiligo, piebaldism, Waardenburg syndrome, and the deadliest skin cancer, melanoma. Through studies of model organisms, the genetic regulatory network of melanocyte development during embryogenesis has been well established. This network also seems to be shared with adult melanocyte regeneration and melanoma formation. To identify chemical regulators of melanocyte development and homeostasis, we screened a small-molecule library of 6000 compounds using zebrafish embryos and identified five novel compounds that inhibited pigmentation. Here we report characterization of two compounds, 12G9 and 36E9, which disrupted melanocyte development. TUNEL assay indicated that these two compounds induced apoptosis of melanocytes. Furthermore, compound 12G9 specifically inhibited the viability of mammalian melanoma cells in vitro. These two compounds should be useful as chemical biology tools to study melanocytes and could serve as drug candidates against melanocyte-related diseases. PMID:22574862

  16. Tryptophan-independent auxin biosynthesis contributes to early embryogenesis in Arabidopsis

    PubMed Central

    Wang, Bing; Chu, Jinfang; Yu, Tianying; Xu, Qian; Sun, Xiaohong; Yuan, Jia; Xiong, Guosheng; Wang, Guodong; Wang, Yonghong; Li, Jiayang

    2015-01-01

    The phytohormone auxin regulates nearly all aspects of plant growth and development. Tremendous achievements have been made in elucidating the tryptophan (Trp)-dependent auxin biosynthetic pathway; however, the genetic evidence, key components, and functions of the Trp-independent pathway remain elusive. Here we report that the Arabidopsis indole synthase mutant is defective in the long-anticipated Trp-independent auxin biosynthetic pathway and that auxin synthesized through this spatially and temporally regulated pathway contributes significantly to the establishment of the apical–basal axis, which profoundly affects the early embryogenesis in Arabidopsis. These discoveries pave an avenue for elucidating the Trp-independent auxin biosynthetic pathway and its functions in regulating plant growth and development. PMID:25831515

  17. Interaction of Cardiopulmonary and Somatic Reflexes in Humans

    PubMed Central

    Walker, John L.; Abboud, Francois M.; Mark, Allyn L.; Thames, Marc D.

    1980-01-01

    Activation of cardiopulmonary receptors with vagal afferents results predominantly in reflex inhibition of efferent sympathetic activity, whereas activation of somatic receptors reflexly increases sympathetic activity to the heart and circulation. Previous studies in experimental animals indicate that there is an important interaction between these excitatory and inhibitory reflexes in the control of the renal circulation. The purpose of this study was to determine whether there is a similar interaction between somatic and cardiopulmonary reflexes in humans. The activity of the cardiopulmonary receptors was altered (reduced) with lower body negative pressure (?5 mm Hg), which causes a decrease in cardiac filling pressure and a small reflex increase in forearm vascular resistance without accompanying changes in arterial pressure. Activation of somatic receptors by isometric handgrip for 2 min at 10 and 20% of maximum voluntary contraction resulted in reflex vasoconstriction in the nonexercising arm. Lower body negative pressure at ?5 mm Hg produced a threefold augmentation in the forearm vasoconstrictor response to isometric handgrip in the nonexercising arm. This increase in resistance was significantly greater (P < 0.05) than the algebraic sum of the increases in resistance resulting from lower body suction alone plus isometric handgrip alone. Furthermore, it occurred despite a greater rise in arterial pressure, which would be expected to decrease forearm vascular resistance through activation of arterial baroreceptors and through passive dilatation of forearm vessels. Thus, removal of the inhibitory influence of cardiopulmonary receptors by pooling blood in the lower extremities enhances the somatic reflex. These data suggest an interaction between cardiopulmonary and somatic reflexes in the control of forearm vascular resistance in man. PMID:7410553

  18. Common Somatic Alterations Identified in Maffucci Syndrome by Molecular Karyotyping

    PubMed Central

    Amyere, Mustapha; Dompmartin, Anne; Wouters, Vinciane; Enjolras, Odile; Kaitila, Ilkka; Docquier, Pierre-Louis; Godfraind, Catherine; Mulliken, John Butler; Boon, Laurence Myriam; Vikkula, Miikka

    2014-01-01

    Maffucci syndrome (MS) is a rare congenital disorder characterized by multiple central cartilaginous tumors (enchondromas) in association with cutaneous spindle cell hemangiomas. These patients have a high incidence of malignant transformation. No familial case is known and the etiopathogenic cause remains unknown. In enchondromatosis (Ollier disease, OD), which is comprised of enchondromas only, 4 mutations in the PTHR1 gene have been identified in 4 patients; 3 were somatic and 1 was germline. No PTHR1 mutations have been detected in MS, whereas somatic IDH1 and, more rarely, IDH2 mutations have been observed in 77% of patients with MS and 81% of patients with OD. These genetic alterations are shared with other tumors, including glioma, leukemia and carcinoma. To search for underlying somatic genomic causes, we screened MS tissues using Affymetrix SNP-chips. We looked for CNVs, LOH and uniparental isodisomy (UPID) by performing pairwise analyses between allelic intensities in tumoral DNA versus the corresponding blood-extracted DNA. While common chromosomal anomalies were absent in constitutional DNA, several shared CNVs were identified in MS-associated tumors. The most frequently encountered somatic alterations were localized in 2p22.3, 2q24.3 and 14q11.2, implicating these chromosomal rearrangements in the formation of enchondromas and spindle cell hemangiomas in MS. In one chondrosarcoma specimen, large amplifications and/or deletions were observed in chromosomes 3, 6, 9, 10, 12, 13, and 19. Some of these genetic changes have been reported in other chondrosarcomas suggesting an etiopathogenic role. No LOH/UPID was observed in any Maffucci tissue. Our findings identify frequent somatic chromosomal rearrangements on 2p22.3, 2q24.3 and 14q11.2, which may unmask mutations leading to the lesions pathognomonic of MS. PMID:25565925

  19. Exploring nervous system transcriptomes during embryogenesis and metamorphosis in Xenopus tropicalis using EST analysis

    PubMed Central

    Fierro, Ana C; Thuret, Raphaël; Coen, Laurent; Perron, Muriel; Demeneix, Barbara A; Wegnez, Maurice; Gyapay, Gabor; Weissenbach, Jean; Wincker, Patrick; Mazabraud, André; Pollet, Nicolas

    2007-01-01

    Background The western African clawed frog Xenopus tropicalis is an anuran amphibian species now used as model in vertebrate comparative genomics. It provides the same advantages as Xenopus laevis but is diploid and has a smaller genome of 1.7 Gbp. Therefore X. tropicalis is more amenable to systematic transcriptome surveys. We initiated a large-scale partial cDNA sequencing project to provide a functional genomics resource on genes expressed in the nervous system during early embryogenesis and metamorphosis in X. tropicalis. Results A gene index was defined and analysed after the collection of over 48,785 high quality sequences. These partial cDNA sequences were obtained from an embryonic head and retina library (30,272 sequences) and from a metamorphic brain and spinal cord library (27,602 sequences). These ESTs are estimated to represent 9,693 transcripts derived from an estimated 6,000 genes. Comparison of these cDNA sequences with protein databases indicates that 46% contain their start codon. Further annotation included Gene Ontology functional classification, InterPro domain analysis, alternative splicing and non-coding RNA identification. Gene expression profiles were derived from EST counts and used to define transcripts specific to metamorphic stages of development. Moreover, these ESTs allowed identification of a set of 225 polymorphic microsatellites that can be used as genetic markers. Conclusion These cDNA sequences permit in silico cloning of numerous genes and will facilitate studies aimed at deciphering the roles of cognate genes expressed in the nervous system during neural development and metamorphosis. The genomic resources developed to study X. tropicalis biology will accelerate exploration of amphibian physiology and genetics. In particular, the model will facilitate analysis of key questions related to anuran embryogenesis and metamorphosis and its associated regulatory processes. PMID:17506875

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

    SciTech Connect

    Homma, Taihei; Shimizu, Miho; Kuroda, Reiko; Kuroda Chiromorphology Team, ERATO-SORST, JST, Komaba, Meguro-ku, Tokyo 153-8902; Department of Life Sciences, Graduate School of Arts and Sciences, The University of Tokyo, Komaba, Meguro-ku, Tokyo 153-8902

    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.

  1. Coordinated metabolic transitions during Drosophila embryogenesis and the onset of aerobic glycolysis.

    PubMed

    Tennessen, Jason M; Bertagnolli, Nicolas M; Evans, Janelle; Sieber, Matt H; Cox, James; Thummel, Carl S

    2014-05-01

    Rapidly proliferating cells such as cancer cells and embryonic stem cells rely on a specialized metabolic program known as aerobic glycolysis, which supports biomass production from carbohydrates. The fruit fly Drosophila melanogaster also utilizes aerobic glycolysis to support the rapid growth that occurs during larval development. Here we use singular value decomposition analysis of modENCODE RNA-seq data combined with GC-MS-based metabolomic analysis to analyze the changes in gene expression and metabolism that occur during Drosophila embryogenesis, spanning the onset of aerobic glycolysis. Unexpectedly, we find that the most common pattern of co-expressed genes in embryos includes the global switch to glycolytic gene expression that occurs midway through embryogenesis. In contrast to the canonical aerobic glycolytic pathway, however, which is accompanied by reduced mitochondrial oxidative metabolism, the expression of genes involved in the tricarboxylic cycle (TCA cycle) and the electron transport chain are also upregulated at this time. Mitochondrial activity, however, appears to be attenuated, as embryos exhibit a block in the TCA cycle that results in elevated levels of citrate, isocitrate, and ?-ketoglutarate. We also find that genes involved in lipid breakdown and ?-oxidation are upregulated prior to the transcriptional initiation of glycolysis, but are downregulated before the onset of larval development, revealing coordinated use of lipids and carbohydrates during development. These observations demonstrate the efficient use of nutrient stores to support embryonic development, define sequential metabolic transitions during this stage, and demonstrate striking similarities between the metabolic state of late-stage fly embryos and tumor cells. PMID:24622332

  2. Genomewide identification of target genes of histone methyltransferase dG9a during Drosophila embryogenesis.

    PubMed

    Shimaji, Kouhei; Konishi, Takahiro; Tanaka, Shintaro; Yoshida, Hideki; Kato, Yasuko; Ohkawa, Yasuyuki; Sato, Tetsuya; Suyama, Mikita; Kimura, Hiroshi; Yamaguchi, Masamitsu

    2015-11-01

    Post-translational modification of the histone plays important roles in epigenetic regulation of various biological processes. Among the identified histone methyltransferases (HMTases), G9a is a histone H3 Lys 9 (H3K9)-specific example active in euchromatic regions. Drosophila G9a (dG9a) has been reported to feature H3K9 dimethylation activity in vivo. Here, we show that the time required for hatching of a homozygous dG9a null mutant and heteroallelic combination of dG9a null mutants is delayed, suggesting that dG9a is at least partially responsible for progression of embryogenesis. Immunocytochemical analyses of the wild-type and the dG9a null mutant flies indicated that dG9a localizes in cytoplasm up to nuclear division cycle 7 where it is likely responsible for di-methylation of nucleosome-free H3K9. From cycles 8-11, dG9a moves into the nucleus and is responsible for di-methylating H3K9 in nucleosomes. RNA-sequence analysis utilizing early wild-type and dG9a mutant embryos showed that dG9a down-regulates expression of genes responsible for embryogenesis. RNA fluorescent in situ hybridization analysis further showed temporal and spatial expression patterns of these mRNAs did not significantly change in the dG9a mutant. These results indicate that dG9a controls transcription levels of some zygotic genes without changing temporal and spatial expression patterns of the transcripts of these genes. PMID:26334932

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

    PubMed

    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. PMID:26316337

  4. Acidocalcisomes as Calcium- and Polyphosphate-Storage Compartments during Embryogenesis of the Insect Rhodnius prolixus Stahl

    PubMed Central

    Ramos, Isabela; Gomes, Fabio; Koeller, Carolina M.; Saito, Katsuharu; Heise, Norton; Masuda, Hatisaburo; Docampo, Roberto; de Souza, Wanderley

    2011-01-01

    Background The yolk of insect eggs is a cellular domain specialized in the storage of reserve components for embryo development. The reserve macromolecules are stored in different organelles and their interactions with the embryo cells are mostly unknown. Acidocalcisomes are lysosome-related organelles characterized by their acidic nature, high electron density and large content of polyphosphate bound to several cations. In this work, we report the presence of acidocalcisome-like organelles in eggs of the insect vector Rhodnius prolixus. Methodology/Principal findings Characterization of the elemental composition of electron-dense vesicles by electron probe X-ray microanalysis revealed a composition similar to that previously described for acidocalcisomes. Following subcellular fractionation experiments, fractions enriched in acidocalcisomes were obtained and characterized. Immunofluorescence showed that polyphosphate polymers and the vacuolar proton translocating pyrophosphatase (V-H+-PPase, considered as a marker for acidocalcisomes) are found in the same vesicles and that these organelles are mainly localized in the egg cortex. Polyphosphate quantification showed that acidocalcisomes contain a significant amount of polyphosphate detected at day-0 eggs. Elemental analyses of the egg fractions showed that 24.5±0.65% of the egg calcium are also stored in such organelles. During embryogenesis, incubation of acidocalcisomes with acridine orange showed that these organelles are acidified at day-3 (coinciding with the period of yolk mobilization) and polyphosphate quantification showed that the levels of polyphosphate tend to decrease during early embryogenesis, being approximately 30% lower at day-3 compared to day-0 eggs. Conclusions We found that acidocalcisomes are present in the eggs and are the main storage compartments of polyphosphate and calcium in the egg yolk. As such components have been shown to be involved in a series of dynamic events that may control embryo growth, results reveal the potential involvement of a novel organelle in the storage and mobilization of inorganic elements to the embryo cells. PMID:22096545

  5. Induction melter apparatus

    DOEpatents

    Roach, Jay A [Idaho Falls, ID; Richardson, John G [Idaho Falls, ID; Raivo, Brian D [Idaho Falls, ID; Soelberg, Nicholas R [Idaho Falls, ID

    2008-06-17

    Apparatus and methods of operation are provided for a cold-crucible-induction melter for vitrifying waste wherein a single induction power supply may be used to effect a selected thermal distribution by independently energizing at least two inductors. Also, a bottom drain assembly may be heated by an inductor and may include an electrically resistive heater. The bottom drain assembly may be cooled to solidify molten material passing therethrough to prevent discharge of molten material therefrom. Configurations are provided wherein the induction flux skin depth substantially corresponds with the central longitudinal axis of the crucible. Further, the drain tube may be positioned within the induction flux skin depth in relation to material within the crucible or may be substantially aligned with a direction of flow of molten material within the crucible. An improved head design including four shells forming thermal radiation shields and at least two gas-cooled plenums is also disclosed.

  6. Induction heating coupler

    NASA Technical Reports Server (NTRS)

    Fox, Robert L. (inventor); Copeland, Carl E. (inventor); Swaim, Robert J. (inventor); Coultrip, Robert H. (inventor); Johnston, David F. (inventor); Phillips, W. Morris (inventor); Johnson, Samuel D. (inventor); Dinkins, James R. (inventor); Buckley, John D. (inventor)

    1994-01-01

    An induction heating device includes a handle having a hollow interior and two opposite ends, a wrist connected to one end of the handle, a U-shaped pole piece having two spaced apart ends, a tank circuit including an induction coil wrapped around the pole piece and a capacitor connected to the induction coil, a head connected to the wrist and including a housing for receiving the U-shaped pole piece, the two spaced apart ends of the pole piece extending outwardely beyond the housing, and a power source connected to the tank circuit. When the tank circuit is energized and a susceptor is placed in juxtaposition to the ends of the U-shaped pole piece, the susceptor is heated by induction heating due to magnetic flux passing between the two ends of the pole piece.

  7. Linear induction accelerator

    DOEpatents

    Buttram, M.T.; Ginn, J.W.

    1988-06-21

    A linear induction accelerator includes a plurality of adder cavities arranged in a series and provided in a structure which is evacuated so that a vacuum inductance is provided between each adder cavity and the structure. An energy storage system for the adder cavities includes a pulsed current source and a respective plurality of bipolar converting networks connected thereto. The bipolar high-voltage, high-repetition-rate square pulse train sets and resets the cavities. 4 figs.

  8. Doubly fed induction machine

    DOEpatents

    Skeist, S. Merrill; Baker, Richard H.

    2005-10-11

    An electro-mechanical energy conversion system coupled between an energy source and an energy load including an energy converter device having a doubly fed induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer coupled to the energy converter device to control the flow of power or energy through the doubly fed induction machine.

  9. Induction launcher design considerations

    NASA Technical Reports Server (NTRS)

    Driga, M. D.; Weldon, W. F.

    1989-01-01

    New concepts in the design of induction accelerators and their power supplies for space and military applications are discussed. Particular attention is given to a piecewise-rising-frequency power supply in which each elementary generator (normal compulsator or rising frequency generator) has a different base frequency. A preliminary design of a coaxial induction accelerator for a hypersonic real gas facility is discussed to illustrate the concepts described.

  10. Induction as Knowledge Integration

    NASA Technical Reports Server (NTRS)

    Smith, Benjamin D.; Rosenbloom, Paul S.

    1996-01-01

    Two key issues for induction algorithms are the accuracy of the learned hypothesis and the computational resources consumed in inducing that hypothesis. One of the most promising ways to improve performance along both dimensions is to make use of additional knowledge. Multi-strategy learning algorithms tackle this problem by employing several strategies for handling different kinds of knowledge in different ways. However, integrating knowledge into an induction algorithm can be difficult when the new knowledge differs significantly from the knowledge the algorithm already uses. In many cases the algorithm must be rewritten. This paper presents Knowledge Integration framework for Induction (KII), a KII, that provides a uniform mechanism for integrating knowledge into induction. In theory, arbitrary knowledge can be integrated with this mechanism, but in practice the knowledge representation language determines both the knowledge that can be integrated, and the costs of integration and induction. By instantiating KII with various set representations, algorithms can be generated at different trade-off points along these dimensions. One instantiation of KII, called RS-KII, is presented that can implement hybrid induction algorithms, depending on which knowledge it utilizes. RS-KII is demonstrated to implement AQ-11, as well as a hybrid algorithm that utilizes a domain theory and noisy examples. Other algorithms are also possible.

  11. Linear induction accelerators

    SciTech Connect

    Briggs, R.J.

    1986-06-01

    The development of linear induction accelerators has been motivated by applications requiring high-pulsed currents of charged particles at voltages exceeding the capability of single-stage, diode-type accelerators and at currents too high for rf accelerators. In principle, one can accelerate charged particles to arbitrarily high voltages using a multi-stage induction machine, but the 50-MeV, 10-kA Advanced Test Accelerator (ATA) at LLNL is the highest voltage machine in existence at this time. The advent of magnetic pulse power systems makes sustained operation at high-repetition rates practical, and this capability for high-average power is very likely to open up many new applications of induction machines in the future. This paper surveys the US induction linac technology with primary emphasis on electron machines. A simplified description of how induction machines couple energy to the electron beam is given, to illustrate many of the general issues that bound the design space of induction linacs.

  12. TRYCAT pathways link peripheral inflammation, nicotine, somatization and depression in the etiology and course of Parkinson's disease.

    PubMed

    Anderson, George; Maes, Michael

    2014-02-01

    Increased depression, somatization, gut inflammation and wider peripheral inflammation are all associated with the early stages of Parkinson's disease (PD). Classically such concurrent conditions have been viewed as "comorbidities", driven by high levels of stress in a still poorly understood and treated disorder. Here we review the data on how oxidative and nitrosative stress in association with immuno-inflammatory responses, drives alteration in tryptophan catabolites, including kynurenine, kynurenic acid and quinolinic acid that drive not only the 'comorbidities" of PD but also important processes in the etiology and course of PD per se. The induction of indoleamine 2,3-dioxygenase, leading to the driving of tryptophan into neuroregulatory tryptophan catabolite products and away from serotonin and melatonin production, has significant implications for understanding the role of nicotine, melatonin, and caffeine in regulating PD susceptibility. Tryptophan catabolite pathway activation will also regulate blood-brain barrier permeability, glia and mast cell reactivity as well as wider innate and adaptive immune cell responses, all relevant to the course of PD. As such, the "comorbidities" of PD such as depression, somatization and peripheral inflammatory disorders can all be conceptualized as being an intricate part of the biological underpinnings of both the etiology and course of PD. As a consequence, the data reviewed here has treatment implications; relevant to both the course of PD and in the management of L-DOPA induced dyskinesias. PMID:23844687

  13. [Hypochondriac symptoms in late-onset depression: the relationship between hypochondria and somatic state of patients].

    PubMed

    Ivanets, N N; Avdeeva, T I; Kinkul'kina, M A

    2013-01-01

    Authors studied 276 women with late-onset depression. Concomitant chronic somatic diseases were identified in 90%. The presence of disease and its nosological definition did not impact on the development of hypochondriac symptoms in patients with late-onset depression. Patients with hypochondriac late-onset depression more often had disability pension due to somatic disease because they more often referred to internists in case of similar objective severity of somatic pathology. It was singled out three variants of the relationship between hypochondria and somatic state: hypernosognostic (a complete coincidence of hypochondria content with actual somatic pathology; anosognostic (a lack of coincidence) and disharmonic (a partial coincidence). The themes of hypochondria in late-nset depressions were correlated with a total number of somatic diseases and their severity. At the same time, there was no correlation between the content of hypochondria and the character of somatic disease. PMID:24077545

  14. Effective combination of aligned nanocomposite nanofibers and human unrestricted somatic stem cells for bone tissue engineering

    PubMed Central

    Bakhshandeh, Behnaz; Soleimani, Masoud; Ghaemi, Nasser; Shabani, Iman

    2011-01-01

    Aim: Bioartificial bone tissue engineering is an increasingly popular technique to solve bone defect challenges. This study aimed to investigate the interactions between matrix composition and appropriate cell type, focusing on hydroxyapatite (HA), to achieve a more effective combination for bone regeneration. Methods: Human unrestricted somatic stem cells (USSCs) were isolated from placental cord blood. The cellular and molecular events during the osteo-induction of USSCs were evaluated for 21 d under the following conditions: (1) in basal culture, (2) supplemented with hydroxyapatite nanoparticle (nHA) suspension, and (3) seeded on electrospun aligned nanofibrous poly-?-caprolactone/poly-L-lactic acid/nHA (PCL/PLLA/nHA) scaffolds. The scaffolds were characterized using scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR) and tensile test. Results: Maintenance of USSCs for 21 d in basal or osteogenic culture resulted in significant increase in osteoblast differentiation. With nHA suspension, even soluble osteo-inductive additives were ineffective, probably due to induced apoptosis of the cells. In contrast to the hindrance of proliferation by nHA suspension, the scaffolds improved cell growth. The scaffolds mimic the nanostructure of natural bone matrix with the combination of PLLA/PCL (organic phase) and HA (inorganic phase) offering a favorable surface topography, which was demonstrated to possess suitable properties for supporting USSCs. Quantitative measurement of osteogenic markers, enzymatic activity and mineralization indicated that the scaffolds did not disturb, but enhanced the osteogenic potential of USSCs. Moreover, the alignment of the fibers led to cell orientation during cell growth. Conclusion: The results demonstrated the synergism of PCL/PLLA/nHA nanofibrous scaffolds and USSCs in the augmentation of osteogenic differentiation. Thus, nHA grafted into PCL/PLLA scaffolds can be a suitable choice for bone tissue regeneration. PMID:21516135

  15. Biolistic transformation of cotton embryogenic cell suspension cultures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic transformation of cotton is highly dependent on the ability to regenerate fertile plants from transgenic cells through somatic embryogenesis. Induction of embryogenic cell cultures is genotype-dependant. However, once embryogenic cell cultures are available, they can be effectively used fo...

  16. Clock-like mutational processes in human somatic cells.

    PubMed

    Alexandrov, Ludmil B; Jones, Philip H; Wedge, David C; Sale, Julian E; Campbell, Peter J; Nik-Zainal, Serena; Stratton, Michael R

    2015-12-01

    During the course of a lifetime, somatic cells acquire mutations. Different mutational processes may contribute to the mutations accumulated in a cell, with each imprinting a mutational signature on the cell's genome. Some processes generate mutations throughout life at a constant rate in all individuals, and the number of mutations in a cell attributable to these processes will be proportional to the chronological age of the person. Using mutations from 10,250 cancer genomes across 36 cancer types, we investigated clock-like mutational processes that have been operating in normal human cells. Two mutational signatures show clock-like properties. Both exhibit different mutation rates in different tissues. However, their mutation rates are not correlated, indicating that the underlying processes are subject to different biological influences. For one signature, the rate of cell division may influence its mutation rate. This study provides the first survey of clock-like mutational processes operating in human somatic cells. PMID:26551669

  17. Determination of somatic mutations in human erythrocytes by cytometry

    SciTech Connect

    Jensen, R.H.; Langlois, R.G.; Bigbee, W.L.

    1985-06-21

    Flow cytometric assays of human erythrocytes labeled with monoclonal antibodies specific for glycophorin A were used to enumerate variant cells that appear in peripheral blood as a result of somatic gene-loss mutations in erythrocyte precursor cells. The assay was performed on erythrocytes from 10 oncology patients who had received at least one treatment from radiation or mutagenic chemotherapy at least 3 weeks before being assayed. The patients were suffering from many different malignancies (e.g., breast, renal, bone, colon and lung), and were treated with several different mutagenic therapeutics (e.g., cisplatinum, adriamycin, daunomycin, or cyclophosphamide). The frequency of these variant cells is an indication of the amount of mutagenic damage accumulated in the individual's erythropoietic cell population. Comparing these results to HPRT clonogenic assays, we find similar baseline frequencies of somatic mutation as well as similar correlation with mutagenic exposures. 9 refs., 3 figs., 1 tab.

  18. Patterns of somatic mutation in human cancer genomes

    PubMed Central

    Greenman, Christopher; Stephens, Philip; Smith, Raffaella; Dalgliesh, Gillian L.; Hunter, Christopher; Bignell, Graham; Davies, Helen; Teague, Jon; Butler, Adam; Stevens, Claire; Edkins, Sarah; O'Meara, Sarah; Vastrik, Imre; Schmidt, Esther E.; Avis, Tim; Barthorpe, Syd; Bhamra, Gurpreet; Buck, Gemma; Choudhury, Bhudipa; Clements, Jody; Cole, Jennifer; Dicks, Ed; Forbes, Simon; Gray, Kris; Halliday, Kelly; Harrison, Rachel; Hills, Katy; Hinton, Jon; Jenkinson, Andy; Jones, David; Menzies, Andy; Mironenko, Tatiana; Perry, Janet; Raine, Keiran; Richardson, Dave; Shepherd, Rebecca; Small, Alexandra; Tofts, Calli; Varian, Jennifer; Webb, Tony; West, Sofie; Widaa, Sara; Yates, Andy; Cahill, Daniel P.; Louis, David N.; Goldstraw, Peter; Nicholson, Andrew G.; Brasseur, Francis; Looijenga, Leendert; Weber, Barbara L.; Chiew, Yoke-Eng; deFazio, Anna; Greaves, Mel F.; Green, Anthony R.; Campbell, Peter; Birney, Ewan; Easton, Douglas F.; Chenevix-Trench, Georgia; Tan, Min-Han; Khoo, Sok Kean; Teh, Bin Tean; Yuen, Siu Tsan; Leung, Suet Yi; Wooster, Richard; Futreal, P. Andrew; Stratton, Michael R.

    2009-01-01

    Cancers arise owing to mutations in a subset of genes that confer growth advantage. The availability of the human genome sequence led us to propose that systematic resequencing of cancer genomes for mutations would lead to the discovery of many additional cancer genes. Here we report more than 1,000 somatic mutations found in 274 megabases (Mb) of DNA corresponding to the coding exons of 518 protein kinase genes in 210 diverse human cancers. There was substantial variation in the number and pattern of mutations in individual cancers reflecting different exposures, DNA repair defects and cellular origins. Most somatic mutations are likely to be ‘passengers’ that do not contribute to oncogenesis. However, there was evidence for ‘driver’ mutations contributing to the development of the cancers studied in approximately 120 genes. Systematic sequencing of cancer genomes therefore reveals the evolutionary diversity of cancers and implicates a larger repertoire of cancer genes than previously anticipated. PMID:17344846

  19. A Cell Electrofusion Chip for Somatic Cells Reprogramming

    PubMed Central

    Wu, Wei; Zeng, Yuxiao; Yang, Jun; Xu, Haiwei; Yin, Zheng Qin

    2015-01-01

    Cell fusion is a potent approach to explore the mechanisms of somatic cells reprogramming. However, previous fusion methods, such as polyethylene glycol (PEG) mediated cell fusion, are often limited by poor fusion yields. In this study, we developed a simplified cell electrofusion chip, which was based on a micro-cavity/ discrete microelectrode structure to improve the fusion efficiency and to reduce multi-cell electrofusion. Using this chip, we could efficiently fuse NIH3T3 cells and mouse embryonic stem cells (mESCs) to induce somatic cells reprogramming. We also found that fused cells demethylated gradually and 5-hydroxymethylcytosine (5hmC) was involved in the demethylation during the reprogramming. Thus, the cell electrofusion chip would facilitate reprogramming mechanisms research by improving efficiency of cell fusion and reducing workloads. PMID:26177036

  20. A model system for analyzing somatic mutations in Drosophila melanogaster.

    PubMed

    Garcia, Ana Maria; Derventzi, Anastasia; Busuttil, Rita; Calder, R Brent; Perez, Ernesto; Chadwell, Linda; Dollé, Martijn E T; Lundell, Martha; Vijg, Jan

    2007-05-01

    Presently there are no good assays for comparing somatic mutation frequencies and spectra between different vertebrate and invertebrate organisms. Here we describe a new lacZ mutation reporter system in D. melanogaster, which complements existing systems in the mouse. The results obtained with the new model indicate two-to threefold higher frequencies of spontaneous mutations than in the mouse, with most of the mutations characterized as large genome rearrangements. PMID:17435764

  1. Recurrent Somatic Structural Variations Contribute to Tumorigenesis in Pediatric Osteosarcoma

    PubMed Central

    Chen, Xiang; Bahrami, Armita; Pappo, Alberto; Easton, John; Dalton, James; Hedlund, Erin; Ellison, David; Shurtleff, Sheila; Wu, Gang; Wei, Lei; Parker, Matthew; Rusch, Michael; Nagahawatti, Panduka; Wu, Jianrong; Mao, Shenghua; Boggs, Kristy; Mulder, Heather; Yergeau, Donald; Lu, Charles; Ding, Li; Edmonson, Michael; Qu, Chunxu; Wang, Jianmin; Li, Yongjin; Navid, Fariba; Daw, Najat; Mardis, Elaine R.; Wilson, Richard K.; Downing, James R.; Zhang, Jinghui; Dyer, Michael A.

    2014-01-01

    Osteosarcoma is a neoplasm of mesenchymal origin with features of osteogenic differentiation. Patients with recurrent or metastatic disease have a very poor prognosis. To define the landscape of somatic mutations in pediatric osteosarcoma, we performed whole-genome sequencing of DNA from 20 osteosarcoma tumor samples and matched normal tissue (obtained from 19 patients) in the discovery cohort as well as 14 samples from 13 patients in the validation cohort. Our results demonstrate that pediatric osteosarcoma is characterized by multiple somatic chromosomal lesions, including structural variations (SVs) and copy number alterations (CNAs). Moreover, single nucleotide variations (SNVs) exhibit a pattern of localized hypermutation called “kataegis” in 50% of the tumors. Despite these regions of kataegis across the osteosarcoma genomes, we detected relatively few recurrent SNVs, and only when SVs were included did we identify the major pathways that are mutated in osteosarcoma. We identified p53 pathway lesions in all 19 patient’s tumors in the discovery cohort, 9 of which were translocations in the first intron of the TP53 gene, leading to gene inactivation. This mechanism of p53 gene inactivation is unique to osteosarcoma among pediatric cancers. In an additional cohort of 32 patients, TP53 gene alterations were identified in 29 of those tumors. Beyond TP53, the RB1, ATRX and DLG2 genes showed recurrent somatic alterations (SNVs and/or SVs) in 29–53% of the tumors. These data highlight the power of whole-genome sequencing in identifying recurrent somatic alterations in cancer genomes that may be missed using other methods. PMID:24703847

  2. Human brain somatic representation: a functional magnetic resonance mapping

    NASA Astrophysics Data System (ADS)

    Romero-Romo, Juan; Rojas, Rafael; Salgado, Perla; Sánchez-Cortázar, Julián; Vazquez-Vela, Arturo; Barrios, Fernando A.

    2001-10-01

    Central nervous system studies of injury and plasticity for the reorganization in the phantom limb sensation area presented. In particular functional magnetic resonance imaging (fMRI) mapping of the somatic and motor cortex of amputee patients, in the case of referred sensations. Using fMRI we can show the correlation between structure and functional field and study the reorganization due to plasticity in the brain.

  3. Review of somatic symptoms in post-traumatic stress disorder.

    PubMed

    Gupta, Madhulika A

    2013-02-01

    Post-traumatic stress disorder (PTSD) is associated with both (1) 'ill-defined' or 'medically unexplained' somatic syndromes, e.g. unexplained dizziness, tinnitus and blurry vision, and syndromes that can be classified as somatoform disorders (DSM-IV-TR); and (2) a range of medical conditions, with a preponderance of cardiovascular, respiratory, musculoskeletal, neurological, and gastrointestinal disorders, diabetes, chronic pain, sleep disorders and other immune-mediated disorders in various studies. Frequently reported medical co-morbidities with PTSD across various studies include cardiovascular disease, especially hypertension, and immune-mediated disorders. PTSD is associated with limbic instability and alterations in both the hypothalamic- pituitary-adrenal and sympatho-adrenal medullary axes, which affect neuroendocrine and immune functions, have central nervous system effects resulting in pseudo-neurological symptoms and disorders of sleep-wake regulation, and result in autonomic nervous system dysregulation. Hypervigilance, a central feature of PTSD, can lead to 'local sleep' or regional arousal states, when the patient is partially asleep and partially awake, and manifests as complex motor and/or verbal behaviours in a partially conscious state. The few studies of the effects of standard PTSD treatments (medications, CBT) on PTSD-associated somatic syndromes report a reduction in the severity of ill-defined and autonomically mediated somatic symptoms, self-reported physical health problems, and some chronic pain syndromes. PMID:23383670

  4. Functional somatic symptoms and hypochondriasis. A survey of empirical studies.

    PubMed

    Kellner, R

    1985-08-01

    Empirical studies suggest the following main conclusions: functional somatic symptoms are extremely common; a large proportion appear to be caused by physiologic activity and tend to be aggravated by emotion. Hypochondriacal patients misunderstand the nature and significance of these symptoms and believe that they are evidence of serious disease. Hypochondriasis can be a part of another syndrome, usually an affective one, or it can be a primary disorder. The prevalence differs between cultures and social classes. Constitutional factors, disease in the family in childhood, and previous disease predispose to hypochondriasis. Various stressors can be precipitating events. Selective perception of symptoms, motivated by fear of disease, and subsequent increase in anxiety with more somatic symptoms appear to be links in the vicious cycle of the hypochondriacal reaction. Psychotherapy as well as psychotropic drugs are effective in the treatment of functional somatic symptoms. There are no adequate controlled studies of psychotherapy in hypochondriasis, and the recommended treatments are based on studies with similar disorders. The prognosis of treated hypochondriasis is good in a substantial proportion of patients. PMID:2861797

  5. Stem cells and somatic cells: reprogramming and plasticity.

    PubMed

    Estrov, Zeev

    2009-01-01

    Recent seminal discoveries have significantly advanced the field of stem cell research and received worldwide attention. Improvements in somatic cell nuclear transfer (SCNT) technology, enabling the cloning of Dolly the sheep, and the derivation and differentiation of human embryonic stem cells raised hopes that normal cells could be generated to replace diseased or injured tissue. At the same time, in vitro and in vivo studies demonstrated that somatic cells of one tissue are capable of generating cells of another tissue. It was theorized that any cell might be reprogrammed, by exposure to a new environment, to become another cell type. This concept contradicts two established hypotheses: (1) that only specific tissues are generated from the endoderm, mesoderm, and ectoderm and (2) that tissue cells arise from a rare population of tissue-specific stem cells in a hierarchical fashion. SCNT, cell fusion experiments, and most recent gene transfer studies also contradict these hypotheses, as they demonstrate that mature somatic cells can be reprogrammed to regain pluripotent (or even totipotent) stem cell capacity. On the basis of the stem cell theory, hierarchical cancer stem cell differentiation models have been proposed. Cancer cell plasticity is an established phenomenon that supports the notion that cellular phenotype and function might be altered. Therefore, mechanisms of cellular plasticity should be exploited and the clinical significance of the cancer stem cell theory cautiously assessed. PMID:19778860

  6. Somatic Activation of AKT3 Causes Hemispheric Developmental Brain Malformations

    PubMed Central

    Poduri, Annapurna; Evrony, Gilad D.; Cai, Xuyu; Elhosary, Princess Christina; Beroukhim, Rameen; Lehtinen, Maria K.; Hills, L. Benjamin; Heinzen, Erin L.; Hill, Anthony; Hill, R. Sean; Barry, Brenda J.; Bourgeois, Blaise F.D.; Riviello, James J.; Barkovich, A. James; Black, Peter M.; Ligon, Keith L.; Walsh, Christopher A.

    2012-01-01

    Summary Hemimegalencephaly (HMG) is a developmental brain disorder characterized by an enlarged, malformed cerebral hemisphere, typically causing epilepsy that requires surgical resection. We studied resected HMG tissue to test whether the condition might reflect somatic mutations affecting genes critical to brain development. We found that 2/8 HMG samples showed trisomy of chromosome 1q, encompassing many genes, including AKT3, which is known to regulate brain size. A third case showed a known activating mutation in AKT3 (c.49G?A, creating p.E17K) that was not present in the patient’s blood cells. Remarkably, the E17K mutation in AKT3 is exactly paralogous to E17K mutations in AKT1 and AKT2 recently discovered in somatic overgrowth syndromes. We show that AKT3 is the most abundant AKT paralogue in brain during neurogenesis and that phosphorylated AKT is abundant in cortical progenitor cells. Our data suggest that somatic mutations limited to brain could represent an important cause of complex neurogenetic disease. PMID:22500628

  7. Diagnostic criteria for psychosomatic research and somatic symptom disorders.

    PubMed

    Sirri, Laura; Fava, Giovanni A

    2013-02-01

    The Diagnostic Criteria for Psychosomatic Research (DCPR) were introduced in 1995 by an international group of investigators to expand the traditional domains of the disease model. The DCPR are a set of 12 'psychosomatic syndromes' which provide operational tools for psychosocial variables with prognostic and therapeutic implications in clinical settings. Eight syndromes concern the main manifestations of abnormal illness behaviour: somatization, hypochondriacal fears and beliefs, and illness denial. The other four syndromes (alexithymia, type A behaviour, demoralization and irritable mood) refer to the domain of psychological factors affecting medical conditions. This review describes the conceptual bases of the DCPR and the main findings concerning their application, with particular reference to the incremental information they added to the customary psychiatric classification. The DCPR were also compared with the provisional DSM-5 somatic symptom disorders. The DCPR were found to be more sensitive than DSM-IV in identifying subthreshold psychological distress and characterizing patients' psychological response to medical illness. DSM-5 somatic symptom disorders seem to neglect important clinical phenomena, such as illness denial, resulting in a narrow view of patients' functioning. The additional information provided by the DCPR may enhance the decision-making process. PMID:23383664

  8. LONO1 Encoding a Nucleoporin Is Required for Embryogenesis and Seed Viability in Arabidopsis1[C][W][OA

    PubMed Central

    Braud, Christopher; Zheng, Wenguang; Xiao, Wenyan

    2012-01-01

    Early embryogenesis in Arabidopsis (Arabidopsis thaliana) is distinguished by a predictable pattern of cell divisions and is a good system for investigating mechanisms of developmental pattern formation. Here, we identified a gene called LONO1 (LNO1) in Arabidopsis in which mutations can abolish the first asymmetrical cell division of the zygote, alter planes and number of cell divisions in early embryogenesis, and eventually arrest embryo development. LNO1 is highly expressed in anthers of flower buds, stigma papilla of open flowers, and embryo and endosperm during early embryogenesis, which is correlated with its functions in reproductive development. The homozygous lno1-1 seed is not viable. LNO1, a homolog of the nucleoporin NUP214 in human (Homo sapiens) and Nup159 in yeast (Saccharomyces cerevisiae), encodes a nucleoporin protein containing phenylalanine-glycine repeats in Arabidopsis. We demonstrate that LNO1 can functionally complement the defect in the yeast temperature-sensitive nucleoporin mutant nup159. We show that LNO1 specifically interacts with the Arabidopsis DEAD-box helicase/ATPase LOS4 in the yeast two-hybrid assay. Furthermore, mutations in AtGLE1, an Arabidopsis homolog of the yeast Gle1 involved in the same poly(A) mRNA export pathway as Nup159, also result in seed abortion. Our results suggest that LNO1 is a component of the nuclear pore complex required for mature mRNA export from the nucleus to the cytoplasm, which makes LNO1 essential for embryogenesis and seed viability in Arabidopsis. PMID:22898497

  9. Three forms of somatization in primary care: prevalence, co-occurrence, and sociodemographic characteristics.

    PubMed

    Kirmayer, L J; Robbins, J M

    1991-11-01

    Three definitions of somatization were operationalized: (a) high levels of functional somatic distress, measured by the Somatic Symptom Index (SSI) of the Diagnostic Interview Schedule; (b) hypochondriasis measured by high scores on a measure of illness worry in the absence of evidence for serious illness; and (c) exclusively somatic clinical presentations among patients with current major depression or anxiety. Of 685 patients attending two family medicine clinics, 26.3% met criteria for one or more forms of somatization. While DSM-III somatization disorder had a prevalence of only 1% in this population, 16.6% of the patients met abridged criteria for subsyndromal somatization disorder (SSI 4,6). Hypochondriacal worry had a prevalence of 7.7% in the clinic sample. Somatized presentations of current major depression or anxiety disorder had a prevalence of 8%. The three forms of somatization were associated with different sociodemographic and illness behavior characteristics. A majority of patients met criteria for only one type of somatization, suggesting that distinct pathogenic processes may be involved in each of the three types. PMID:1940887

  10. Kinetic Inductance Magnetometer

    E-print Network

    Luomahaara, Juho; Grönberg, Leif; Hassel, Juha

    2014-01-01

    Ultrasensitive magnetic field detection is utilized in the fields of science, medicine and industry. We report on a novel magnetometer relying on the kinetic inductance of superconducting material. The kinetic inductance exhibits a non-linear response with respect to DC current, a fact that is exploited by applying magnetic flux through a superconducting loop to generate a shielding current and a change in the inductance of the loop. The magnetometer is arranged into a resonator, allowing readout through a transmission measurement that makes the device compatible with radio frequency multiplexing techniques. The device is fabricated using a single thin-film layer of NbN, simplifying the fabrication process compared to existing magnetometer technologies considerably. Our experimental data, supported by theory, demonstrates a magnetometer having potential to replace established technology in applications requiring ultra-high sensitivity.

  11. Wrapper Induction Software

    Energy Science and Technology Software Center (ESTSC)

    2011-08-18

    Wrapper Induction is a software package that allows for unsupervised, semi-supervised, and manual extraction of social media data independent of language or site architecture. A large range of blog formats is available to individuals as means of publishing data to the internet. Blogs are a source of rich information for analysts. With a growing volume of information and blog engines, there is an increased need for automatic or semi-automatic extraction of that data for processingmore »to help deliver results to analysts. Wrapper Induction is designed to automatically or semi-automatically create a template that can be used to harvest blog data from websites. Blogs are in a variety of formats and languages. Wrapper Induction creates a template and extracts blog data in a way that is independent of a specified blog format or language.« less

  12. Wrapper Induction Software

    SciTech Connect

    2011-08-18

    Wrapper Induction is a software package that allows for unsupervised, semi-supervised, and manual extraction of social media data independent of language or site architecture. A large range of blog formats is available to individuals as means of publishing data to the internet. Blogs are a source of rich information for analysts. With a growing volume of information and blog engines, there is an increased need for automatic or semi-automatic extraction of that data for processing to help deliver results to analysts. Wrapper Induction is designed to automatically or semi-automatically create a template that can be used to harvest blog data from websites. Blogs are in a variety of formats and languages. Wrapper Induction creates a template and extracts blog data in a way that is independent of a specified blog format or language.

  13. Stress Responsive Proteins Are Actively Regulated during Rice (Oryza sativa) Embryogenesis as Indicated by Quantitative Proteomics Analysis

    PubMed Central

    Zi, Jin; Zhang, Jiyuan; Wang, Quanhui; Zhou, Baojin; Zhong, Junyan; Zhang, Chaoliang; Qiu, Xuemei; Wen, Bo; Zhang, Shenyan; Fu, Xiqin; Lin, Liang; Liu, Siqi

    2013-01-01

    Embryogenesis is the initial step in a plant’s life, and the molecular changes that occur during embryonic development are largely unknown. To explore the relevant molecular events, we used the isobaric tags for relative and absolute quantification (iTRAQ) coupled with the shotgun proteomics technique (iTRAQ/Shotgun) to study the proteomic changes of rice embryos during embryogenesis. For the first time, a total of 2 165 unique proteins were identified in rice embryos, and the abundances of 867 proteins were actively changed based on the statistical evaluation of the quantitative MS/MS signals. The quantitative data were then confirmed using multiple reactions monitoring (MRM) and were also supported by our previous study based on two-dimensional gel electrophoresis (2 DE). Using the proteome at 6 days after pollination (DAP) as a reference, cluster analysis of these differential proteins throughout rice embryogenesis revealed that 25% were up-regulated and 75% were down-regulated. Gene Ontology (GO) analysis implicated that most of the up-regulated proteins were functionally categorized as stress responsive, mainly including heat shock-, lipid transfer-, and reactive oxygen species-related proteins. The stress-responsive proteins were thus postulated to play an important role during seed maturation. PMID:24058531

  14. Carbohydrate metabolism of eggs of the whitefish, Coregonus spp. during embryogenesis and its relationship with egg quality.

    PubMed

    Lahnsteiner, Franz

    2005-09-01

    The present study investigated the changes in carbohydrate metabolism of eggs of the whitefish, Coregonus spp. during embryogenesis (unfertilized eggs to embryos in the eyed stage). Occurrence of glycolysis was proved by activities of phosphofructokinase (PFK-1) and pyruvate kinase and by decreasing levels of hexose, pentose phosphate pathway by transaldolase (non-oxidative path) and glucose-6-phosphate dehydrogenase activities (oxidative path) and by increasing ribose levels, fructose synthesis (polyol pathway) by sorbitol dehydrogenase activities, gluconeogenesis by activities of glucose-6-phosphatase. Glycolysis and pentose phosphate pathway had highest activities up to the epiboly stage, gluconeogenesis from epiboly stage to the eyed embryo stage. Coregonus spp. eggs contained hexoses, ketoses, 6-deoxyhexoses, heptoses and uronic acids with hexoses, ketoses, and 6-deoxysugars occurring free and in bound form. Hexoses were found in highest quantities, followed by ketoses, and 6-deoxyhexoses. Levels of these compounds changed in a specific way during embryogenesis. During all investigated stages of embryogenesis, the levels of ribose, heptose, and ketose were correlated with the percentage of eyed stage embryos developing out of the fertilized eggs (egg viability). In distinct embryonic stages, the levels of hexoses and 6-deoxyhexoses and the activities of glucose-6-phosphatase were also correlated with egg quality. This ascertains the importance of carbohydrate metabolism for developing eggs. PMID:16046162

  15. Expression patterns of esophageal cancer deregulated genes in C57BL/6J mouse embryogenesis

    PubMed Central

    Zhang, Jian; Gao, Fu-Lu; Zhi, Hui-Ying; Luo, Ai-Ping; Ding, Fang; Wu, Min; Liu, Zhi-Hua

    2004-01-01

    AIM: To investigate the expression patterns of esophageal squamous cell cancer deregulated genes in mid to late stages of C57BL/6J mouse embryogenesis, and the correlation between these genes in embryonic development and tumorigenesis of esophageal squamous cell cancer. METHODS: Reverse northern screening was performed to examine the expression patterns of esophageal cancer deregulated genes in C57BL/6J mouse embryogenesis. To confirm the gene expression patterns, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was carried out for 3 of the randomly picked differentially expressed genes. RESULTS: Within these esophageal cancer deregulated genes, 4 patterns of expression were observed at 3 stages embryonic d 11.5 (E11.5), embryonic d 13.5 (E13.5) and postnatal d1 (P1). (1) Up-regulation during the E11.5 period, down- regulation during the E13.5 and P1 period (up-down-down), the 10 up-regulated genes during the E11.5 period could be classified into 6 known genes and 4 unknown genes. The known genes included differentiation related genes (S100A8), immunity related gene (IGL), translation and transcription regulation genes (RPL15, EEF1A1), cytoskeletal protein (TUBA1), cysteine protease inhibitor (cystatin B). (2) Up-regulation during the E13.5 and P1 period (down-up-up), such as the SPRR2A which was down-regulated at E11.5. (3) Down-regulation during the E11.5 and E13.5 period (down-down-up), such as RHCG and keratin 4. (4) Fluctuating expression, down initially, up at E13.5, and then down again (down-up-down). EMP1 belonged to such a gene, which was highly expressed at E13.5. CONCLUSION: The results will be helpful for understanding the function of esophageal squamous cell carcinoma (ESCC) deregulated genes in embryonic development and tumorigenesis. S100A8 and S100A9 may play different roles in early embryonic development. IGL may be an oncofetal protein, and EMP1 relates with neurogenesis at E13.5. The genes identified pertinent to embryonic development may serve as candidate susceptibility genes for inherited esophageal cancer disorders as well as for various heritable disorders of embryonic development. PMID:15069704

  16. 3D early embryogenesis image filtering by nonlinear partial differential equations.

    PubMed

    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 are artificially connected due to acquisition error intrinsically linked to physics of LSM. In all studied aspects it turned out that the nonlinear diffusion filter which is called geodesic mean curvature flow (GMCF) has the best performance. PMID:20457535

  17. A Synthetic Lethal Screen Identifies a Role for Lin-44/Wnt in C. elegans Embryogenesis

    PubMed Central

    Hartin, Samantha N.; Hudson, Martin L.; Yingling, Curtis; Ackley, Brian D.

    2015-01-01

    Background The C. elegans proteins PTP-3/LAR-RPTP and SDN-1/Syndecan are conserved cell adhesion molecules. Loss-of-function (LOF) mutations in either ptp-3 or sdn-1 result in low penetrance embryonic developmental defects. Work from other systems has shown that syndecans can function as ligands for LAR receptors in vivo. We used double mutant analysis to test whether ptp-3 and sdn-1 function in a linear genetic pathway during C. elegans embryogenesis. Results We found animals with LOF in both sdn-1 and ptp-3 exhibited a highly penetrant synthetic lethality (SynLet), with only a small percentage of animals surviving to adulthood. Analysis of the survivors demonstrated that these animals had a synergistic increase in the penetrance of embryonic developmental defects. Together, these data strongly suggested PTP-3 and SDN-1 function in parallel during embryogenesis. We subsequently used RNAi to knockdown ~3,600 genes predicted to encode secreted and/or transmembrane molecules to identify genes that interacted with ptp-3 or sdn-1. We found that the Wnt ligand, lin-44, was SynLet with sdn-1, but not ptp-3. We used 4-dimensional time-lapse analysis to characterize the interaction between lin-44 and sdn-1. We found evidence that loss of lin-44 caused defects in the polarization and migration of endodermal precursors during gastrulation, a previously undescribed role for lin-44 that is strongly enhanced by the loss of sdn-1. Conclusions PTP-3 and SDN-1 function in compensatory pathways during C. elegans embryonic and larval development, as simultaneous loss of both genes has dire consequences for organismal survival. The Wnt ligand lin-44 contributes to the early stages of gastrulation in parallel to sdn-1, but in a genetic pathway with ptp-3. Overall, the SynLet phenotype provides a robust platform to identify ptp-3 and sdn-1 interacting genes, as well as other genes that function in development, yet might be missed in traditional forward genetic screens. PMID:25938228

  18. HIGH GRADIENT INDUCTION ACCELERATOR

    SciTech Connect

    Caporaso, G J; Sampayan, S; Chen, Y; Blackfield, D; Harris, J; Hawkins, S; Holmes, C; Krogh, M; Nelson, S; Nunnally, W; Paul, A; Poole, B; Rhodes, M; Sanders, D; Selenes, K; Sullivan, J; Wang, L; Watson, J

    2007-06-21

    A new type of compact induction accelerator is under development at the Lawrence Livermore National Laboratory that promises to increase the average accelerating gradient by at least an order of magnitude over that of existing induction machines. The machine is based on the use of high gradient vacuum insulators, advanced dielectric materials and switches and is stimulated by the desire for compact flash x-ray radiography sources. Research describing an extreme variant of this technology aimed at proton therapy for cancer will be described. Progress in applying this technology to several applications will be reviewed.

  19. Replication of somatic micronuclei in bovine enucleated oocytes

    PubMed Central

    2012-01-01

    Background Microcell-mediated chromosome transfer (MMCT) was developed to introduce a low number of chromosomes into a host cell. We have designed a novel technique combining part of MMCT with somatic cell nuclear transfer, which consists of injecting a somatic micronucleus into an enucleated oocyte, and inducing its cellular machinery to replicate such micronucleus. It would allow the isolation and manipulation of a single or a low number of somatic chromosomes. Methods Micronuclei from adult bovine fibroblasts were produced by incubation in 0.05 ?g/ml demecolcine for 46 h followed by 2 mg/ml mitomycin for 2 h. Cells were finally treated with 10 ?g/ml cytochalasin B for 1 h. In vitro matured bovine oocytes were mechanically enucleated and intracytoplasmatically injected with one somatic micronucleus, which had been previously exposed [Micronucleus- injected (+)] or not [Micronucleus- injected (?)] to a transgene (50 ng/?l pCX-EGFP) during 5 min. Enucleated oocytes [Enucleated (+)] and parthenogenetic [Parthenogenetic (+)] controls were injected into the cytoplasm with less than 10 pl of PVP containing 50 ng/?l pCX-EGFP. A non-injected parthenogenetic control [Parthenogenetic (?)] was also included. Two hours after injection, oocytes and reconstituted embryos were activated by incubation in 5 ?M ionomycin for 4 min + 1.9 mM 6-DMAP for 3 h. Cleavage stage and egfp expression were evaluated. DNA replication was confirmed by DAPI staining. On day 2, Micronucleus- injected (?), Parthenogenetic (?) and in vitro fertilized (IVF) embryos were karyotyped. Differences among treatments were determined by Fisher?s exact test (p?0.05). Results All the experimental groups underwent the first cell divisions. Interestingly, a low number of Micronucleus-injected embryos showed egfp expression. DAPI staining confirmed replication of micronuclei in most of the evaluated embryos. Karyotype analysis revealed that all Micronucleus-injected embryos had fewer than 15 chromosomes per blastomere (from 1 to 13), while none of the IVF and Parthenogenetic controls showed less than 30 chromosomes per spread. Conclusions We have developed a new method to replicate somatic micronuclei, by using the replication machinery of the oocyte. This could be a useful tool for making chromosome transfer, which could be previously targeted for transgenesis. PMID:23173571

  20. Regulation of growth-blocking peptide expression during embryogenesis of the cabbage army worm

    SciTech Connect

    Tsuzuki, Seiji; Sekiguchi, Shiroh; Hayakawa, Yoichi . E-mail: hayakayo@cc.saga-u.ac.jp

    2005-10-07

    Growth-blocking peptide (GBP) is an insect cytokine with diverse biological functions. Northern blot analysis revealed high heterogeneity in the size distribution of GBP mRNAs as well as in the tissues where they are detected. The s patio-temporal transcription pattern is dynamic, especially during embryogenesis. Gel shift assays demonstrated that the cabbage army worm embryo nuclear extract specifically binds to a 178-bp element, at position +234 to +411 from the transcription start site of the 1.3 kb GBP transcript, in which two Drosophila Deformed (DfD) binding sites are repeated in tandem. The specific binding between this element and Dfd was demonstrated using recombinant cabbage armyworm Dfd protein. Silencing the Dfd expression in embryos by treating with DfD double-stranded RNA did not reduce the expression level of GBP, but ectopic GBP expression was observed in the lateral region of the embryo, suggesting that DD could serve as a transcriptional repressor for the GBP gene.

  1. Membrane-type MMPs enable extracellular matrix permissiveness and mesenchymal cell proliferation during embryogenesis

    PubMed Central

    Shi, Joanne; Son, Mi-Young; Yamada, Susan; Szabova, Ludmila; Kahan, Stacie; Chrysovergis, Kaliopi; Wolf, Lauren; Surmak, Andrew; Holmbeck, Kenn

    2008-01-01

    Peri-cellular remodeling of mesenchymal extracellular matrices is considered a prerequisite for cell proliferation, motility and development. Here we demonstrate that membrane-type 3 MMP, MT3-MMP, is expressed in mesenchymal tissues of the skeleton and in peri-skeletal soft connective tissue. Consistent with this localization, MT3-MMP-deficient mice display growth inhibition tied to a decreased viability of mesenchymal cells in skeletal tissues. We document that MT3-MMP works as a major collagenolytic enzyme, enabling cartilage and bone cells to cleave high-density fibrillar collagen and modulate their resident matrix to make it permissive for proliferation and migration. Collectively, these data uncover a novel extracellular matrix remodeling mechanism required for proper function of mesenchymal cells. The physiological significance of MT3-MMP is highlighted in mice double deficient for MT1-MMP and MT3-MMP. Double deficiency transcends the combined effects of the individual single deficiencies and leads to severe embryonic defects in palatogenesis and bone formation incompatible with life. These defects are directly tied to loss of indispensable collagenolytic activities required in collagen-rich mesenchymal tissues for extracellular matrix remodeling and cell proliferation during embryogenesis. PMID:18022611

  2. Loss of Foxm1 Results in Reduced Somatotrope Cell Number during Mouse Embryogenesis

    PubMed Central

    Bailey, Brock; Jung, Deborah O.; Navratil, Amy M.; Ellsworth, Buffy S.

    2015-01-01

    FOXM1, a member of the forkhead box transcription factor family, plays a key role in cell cycling progression by regulating the expression of critical G1/S and G2/M phase transition genes. In vivo studies reveal that Foxm1 null mice have a 91% lethality rate at e18.5 due to significant cardiovascular and hepatic hypoplasia. Thus, FOXM1 has emerged as a key protein regulating mitotic division and cell proliferation necessary for embryogenesis. In the current study, we assess the requirement for Foxm1 in the developing pituitary gland. We find that Foxm1 is expressed in the pituitary at embryonic days 10.5-e18.5 and localizes with markers for active cell proliferation (BrdU). Interestingly, direct analysis of Foxm1 null mice at various embryonic ages, reveals no difference in gross pituitary morphology or cell proliferation. We do observe a downward trend in overall pituitary cell number and a small reduction in pituitary size in e18.5 embryos suggesting there may be subtle changes in pituitary proliferation not detected with our proliferation makers. Consistent with this, Foxm1 null mice have reductions in both the somatotrope and gonadotrope cell populations. PMID:26075743

  3. Creatine synthesis and transport during rat embryogenesis: Spatiotemporal expression of AGAT, GAMT and CT1

    PubMed Central

    Braissant, Olivier; Henry, Hugues; Villard, Anne-Marie; Speer, Oliver; Wallimann, Theo; Bachmann, Claude

    2005-01-01

    Background Creatine (Cr) is synthesized by a two-step mechanism involving arginine:glycine amidinotransferase (AGAT) and guanidinoacetate methyltransferase (GAMT), and is taken up by cells through a specific Cr transporter, CT1. Recently, genetic defects of this pathway have been described, that lead to Cr deficiency, neurological symptoms in early infancy and severe neurodevelopmental delay. To investigate the involvement of Cr synthesis and uptake pathways during embryonic development, we determined the spatiotemporal expression of AGAT, GAMT and CT1 during the rat embryogenesis, at the mRNA and protein level. Results We show that AGAT and GAMT are expressed in hepatic primordium as soon as 12.5 days, then progressively acquire their adult pattern of expression, with high levels of AGAT in kidney and pancreas, and high levels of GAMT in liver and pancreas. AGAT and CT1 are prominent in CNS, skeletal muscles and intestine, where they appear earlier than GAMT. High levels of CT1 are found in epithelia. Conclusion Our results suggest that de novo synthesis of Cr by AGAT and GAMT, as well as cellular Cr uptake by CT1, are essential during embryonic development. This work provides new clues on how creatine can be provided to developing tissues, and suggests that Cr deficiencies might induce irreversible damages already in utero, particularly on the nervous system. PMID:15918910

  4. Reproduction and embryogenesis of the mandi-amarelo catfish, Pimelodus maculatus (Pisces, Pimelodidae), in captivity.

    PubMed

    Arantes, F P; Borçato, F L; Sato, Y; Rizzo, E; Bazzoli, N

    2013-02-01

    To study reproduction and embryogenesis, Pimelodus maculatus specimens were kept in captivity and captured bimonthly during 1 year. Gonads samples (211 specimens) were collected and submitted to routine histological techniques. Pimelodus maculatus prepared to reproduce when water temperature was high, and even reached advanced maturation but did not spawn in captivity. Spent fish gonads were not documented, and atretic follicles were frequent (60%) in late maturation females. When then submitted to hypophysation, 70% of the females responded positively to hormonal treatment. Oocyte extrusion occurred 8 h after a second hormonal injection at 26°C. The fertilisation rate was 65.1 ± 9.2% at 24°C. Recently spawned oocytes of P. maculatus were spherical, non-adhesive, yellow in colour, with an average diameter of 1113.92 ± 37.02 ?m and covered by a thick gelatinous layer. Blastopore closure occurred 7 h and 30 min after fertilisation. Embryonic development was completed within 18 h after fertilisation. The results of this work provide important knowledge for the handling and cultivation of not only P. maculatus, but other species of potential value for fish culture. PMID:22612443

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

    SciTech Connect

    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.

  6. Regulation of embryogenesis by light and its ecological significance in the Asian Tadpole shrimp Triops granarius.

    PubMed

    Horiguchi, Tsutomu; Ito, Chihiro; Numata, Hideharu

    2009-07-01

    Triops granarius (Lucas) (Notostraca: Triopsidae) lives In paddy fields from the Kanto district to northern Kyushu, Japan. Changes in the size distribution of this species were examined in the paddy fields and then the effect of light on hatching was examined under quasi-natural and laboratory conditions. Adult tadpole shrimps were found about one week after irrigation and plowing in two paddy fields in Sakai, Japan. They developed rapidly and disappeared altogether about one month later. Under conditions of natural daylength and temperature, eggs laid in the soil did not hatch without being removed from the soil. Under constant light at 25 degrees C, the lower the light intensity was, the longer the eggs took to hatch. Moreover, most eggs kept in constant darkness did not hatch, but many of them hatched within a short period after being transferred to constant light with an intensity of 0.3 W/m(2) or more. Because a 1-h light pulse was found to induce hatching, light is considered necessary for the resumption of embryonic development. These results suggest that eggs of T. granarius laid in the soil do not hatch without exposure to light; consequently, this species has a univoltine life cycle in the paddy fields. Histological observations revealed that under constant darkness, embryonic development was arrested at an early stage of organogenesis, in which the nauplius eye had not yet formed. We discuss the role of light in the regulation of embryogenesis in T. granarius. PMID:19663643

  7. CHD1 acts via the Hmgpi pathway to regulate mouse early embryogenesis.

    PubMed

    Suzuki, Shinnosuke; Nozawa, Yusuke; Tsukamoto, Satoshi; Kaneko, Takehito; Manabe, Ichiro; Imai, Hiroshi; Minami, Naojiro

    2015-07-01

    The protein CHD1 is a member of the family of ATPase-dependent chromatin remodeling factors. CHD1, which recognizes trimethylated histone H3 lysine 4, has been implicated in transcriptional activation in organisms ranging from yeast to humans. It is required for pre-mRNA maturation, maintenance of mouse embryonic stem cell pluripotency and rapid growth of the mouse epiblast. However, the function(s) of CHD1 in mouse preimplantation embryos has not yet been examined. Here, we show that loss of CHD1 function led to embryonic lethality after implantation. In mouse embryos in which Chd1 was targeted by siRNA microinjection, the expression of the key regulators of cell fate specification Pou5f1 (also known as Oct4), Nanog and Cdx2 was dramatically decreased, starting at mid-preimplantation gene activation (MGA). Moreover, expression of Hmgpi and Klf5, which regulate Pou5f1, Nanog and Cdx2, was also significantly suppressed at zygotic gene activation (ZGA). Suppression of Hmgpi expression in Chd1-knockdown embryos continued until the blastocyst stage, whereas suppression of Klf5 expression was relieved by the morula stage. Next, we rescued HMGPI expression via Hmgpi mRNA microinjection in Chd1-knockdown embryos. Consequently, Pou5f1, Nanog and Cdx2 expression was restored at MGA and live offspring were recovered. These findings indicate that CHD1 plays important roles in mouse early embryogenesis via activation of Hmgpi at ZGA. PMID:26092847

  8. The GYF domain protein CD2BP2 is critical for embryogenesis and podocyte function.

    PubMed

    Albert, Gesa I; Schell, Christoph; Kirschner, Karin M; Schäfer, Sebastian; Naumann, Ronald; Müller, Alexandra; Kretz, Oliver; Kuropka, Benno; Girbig, Mathias; Hübner, Norbert; Krause, Eberhard; Scholz, Holger; Huber, Tobias B; Knobeloch, Klaus-Peter; Freund, Christian

    2015-10-01

    Scaffolding proteins play pivotal roles in the assembly of macromolecular machines such as the spliceosome. The adaptor protein CD2BP2, originally identified as a binding partner of the adhesion molecule CD2, is a pre-spliceosomal assembly factor that utilizes its glycine-tyrosine-phenylalanine (GYF) domain to co-localize with spliceosomal proteins. So far, its function in vertebrates is unknown. Using conditional gene targeting in mice, we show that CD2BP2 is crucial for embryogenesis, leading to growth retardation, defects in vascularization, and premature death at embryonic day 10.5 when absent. Ablation of the protein in bone marrow-derived macrophages indicates that CD2BP2 is involved in the alternative splicing of mRNA transcripts from diverse origins. At the molecular level, we identified the phosphatase PP1 to be recruited to the spliceosome via the N-terminus of CD2BP2. Given the strong expression of CD2BP2 in podocytes of the kidney, we use selective depletion of CD2BP2, in combination with next-generation sequencing, to monitor changes in exon usage of genes critical for podocyte functions, including VEGF and actin regulators. CD2BP2-depleted podocytes display foot process effacement, and cause proteinuria and ultimately lethal kidney failure in mice. Collectively, our study defines CD2BP2 as a non-redundant splicing factor essential for embryonic development and podocyte integrity. PMID:26082520

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

    PubMed

    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. PMID:22327190

  10. Sexual dimorphism in the early embryogenesis of the chicken (Gallus Gallus domesticus).

    PubMed

    Tagirov, Makhsud; Golovan, Serguei

    2015-05-01

    Studies of dioecious animals suggest that sex-specific development occurs from the onset of embryogenesis. This must be accounted for when addressing issues involving sex-ratio regulation in domestic animals and conservation biology. We investigated the occurrence of growth-rate sexual dimorphism in 84 chicken embryos incubated for 30 hr and nucleic-acid abundance in 99 embryos incubated for 4 hr. Comparative expression of the genes engaged in cell-cycle regulation (16 genes), embryo growth (10 genes), metabolic activity (2 genes), and epigenetic regulation (4 genes) in 4-hr male and female embryos were further analyzed by reverse-trancriptase quantitative PCR. At the stage when somite structure commences, males are growing faster than females. DNA and RNA yields at 4 hr are elevated in males compared to females, and most cell-proliferation-promoting genes are overexpressed in males. Expression of key metabolic genes (G6PD and HPRT) and the principal genes responsible for DNA methylation (DNMTs), however, does not differ between the sexes. These data suggest that the faster growth of early male embryos is conserved among mammalian and bird phyla, and may have an evolutionary importance. PMID:25772689

  11. The E3 Ubiquitin Ligase Activity of Trip12 Is Essential for Mouse Embryogenesis

    PubMed Central

    Kajiro, Masashi; Tsuchiya, Mai; Kawabe, Yoh-ichi; Furumai, Ryohei; Iwasaki, Naoya; Hayashi, Yuki; Katano, Miyuki; Nakajima, Yuka; Goto, Natsuka; Watanabe, Tatsuya; Murayama, Akiko; Oishi, Hisashi; Ema, Masatsugu; Takahashi, Satoru; Kishimoto, Hiroyuki; Yanagisawa, Junn

    2011-01-01

    Protein ubiquitination is a post-translational protein modification that regulates many biological conditions [1], [2], [3], [4]. Trip12 is a HECT-type E3 ubiquitin ligase that ubiquitinates ARF and APP-BP1 [5], [6]. 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 (Trip12mt/mt) that disrupts the ubiquitin ligase activity resulted in embryonic lethality in the middle stage of development. Trip12mt/mt embryos exhibited growth arrest and increased expression of the negative cell cycle regulator p16 [7], [8], [9], [10]. In contrast, Trip12mt/mt ES cells were viable. They had decreased proliferation, but maintained both the undifferentiated state and the ability to differentiate. Trip12mt/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. PMID:22028794

  12. Galactolipid synthesis in chloroplast inner envelope is essential for proper thylakoid biogenesis, photosynthesis, and embryogenesis.

    PubMed

    Kobayashi, Koichi; Kondo, Maki; Fukuda, Hiroaki; Nishimura, Mikio; Ohta, Hiroyuki

    2007-10-23

    The biogenesis of thylakoid membranes, an indispensable event for the photoautotrophic growth of plants, requires a significant increase in the level of the unique thylakoid membrane lipid monogalactosyldiacylglycerol (MGDG), which constitutes the bulk of membrane lipids in chloroplasts. The final step in MGDG biosynthesis occurs in the plastid envelope and is catalyzed by MGDG synthase. Here we report the identification and characterization of an Arabidopsis mutant showing a complete defect in MGDG synthase 1. The mutant seeds germinated as small albinos only in the presence of sucrose. The seedlings lacked galactolipids and had disrupted photosynthetic membranes, leading to the complete impairment of photosynthetic ability and photoautotrophic growth. Moreover, invagination of the inner envelope, which is not seen in mature WT chloroplasts, was observed in the mutant, supporting an old hypothesis that envelope invagination is a major event in early chloroplast biogenesis. In addition to the defective seedling phenotype, embryo development was arrested in the mutant, although seeds with impaired embryos could germinate heterotrophically. These results demonstrate the importance of galactolipids not only in photosynthetic growth but also in embryogenesis. PMID:17940034

  13. Levels of free PABP are limited by newly polyadenylated mRNA in early Spisula embryogenesis

    PubMed Central

    de Melo Neto, Osvaldo P.; Walker, James A.; de Sa, Cezar Martins; Standart, Nancy

    2000-01-01

    The poly(A) tail of eukaryotic mRNAs regulates translation and RNA stability through an association with the poly(A)-binding protein (PABP). The role of PABP in selective polyadenylation/deadenylation and translational recruitment/repression of maternal mRNAs that occurs in early development is not fully understood. Here, we report studies including UV-crosslinking and immunoblotting assays to characterise PABP in the early developmental stages of the clam Spisula solidissima. A single, 70 kDa PABP, whose sequence is highly homologous to vertebrate, yeast and plant PABPs, is detected in oocytes. The levels of clam PABP are constant in early embryogenesis, although its ability to crosslink labelled poly(A) is ‘masked’ shortly after fertilisation and remains so until the larval stage. Full RNA-binding potential of PABP in embryo lysates was achieved by brief denaturation with guanidinium hydrochloride followed by dilution for binding and crosslinking or by controlled treatment of lysates with Ca2+-dependent micrococcal nuclease. Masking of PABP, which accompanies cytoplasmic polyadenylation in maturing oocytes and in in vitro activated oocyte lysates, is very likely due to an association with mRNAs that bear new PABP target binding sites and thus prevent protein binding to the labelled A-rich probe. Functional implications of these findings as well as the potential application of this unmasking method to other RNA-binding proteins is discussed. PMID:10954604

  14. Plasticity in Cell Division Patterns and Auxin Transport Dependency during in Vitro Embryogenesis in Brassica napus.

    PubMed

    Soriano, Mercedes; Li, Hui; Jacquard, Cédric; Angenent, Gerco C; Krochko, Joan; Offringa, Remko; Boutilier, Kim

    2014-06-20

    In Arabidopsis thaliana, zygotic embryo divisions are highly regular, but it is not clear how embryo patterning is established in species or culture systems with irregular cell divisions. We investigated this using the Brassica napus microspore embryogenesis system, where the male gametophyte is reprogrammed in vitro to form haploid embryos in the absence of exogenous growth regulators. Microspore embryos are formed via two pathways: a zygotic-like pathway, characterized by initial suspensor formation followed by embryo proper formation from the distal cell of the suspensor, and a pathway characterized by initially unorganized embryos lacking a suspensor. Using embryo fate and auxin markers, we show that the zygotic-like pathway requires polar auxin transport for embryo proper specification from the suspensor, while the suspensorless pathway is polar auxin transport independent and marked by an initial auxin maximum, suggesting early embryo proper establishment in the absence of a basal suspensor. Polarity establishment in this suspensorless pathway was triggered and guided by rupture of the pollen exine. Irregular division patterns did not affect cell fate establishment in either pathway. These results confirm the importance of the suspensor and suspensor-driven auxin transport in patterning, but also uncover a mechanism where cell patterning is less regular and independent of auxin transport. PMID:24951481

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

    SciTech Connect

    Jia, Fengjuan Qi, Shengdong Li, Hui Liu, Pu Li, Pengcheng Wu, Changai Zheng, Chengchao Huang, Jinguang

    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.

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

    NASA Astrophysics Data System (ADS)

    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. Dachsous1b cadherin regulates actin and microtubule cytoskeleton during early zebrafish embryogenesis.

    PubMed

    Li-Villarreal, Nanbing; Forbes, Meredyth M; Loza, Andrew J; Chen, Jiakun; Ma, Taylur; Helde, Kathryn; Moens, Cecilia B; Shin, Jimann; Sawada, Atsushi; Hindes, Anna E; Dubrulle, Julien; Schier, Alexander F; Longmore, Gregory D; Marlow, Florence L; Solnica-Krezel, Lilianna

    2015-08-01

    Dachsous (Dchs), an atypical cadherin, is an evolutionarily conserved regulator of planar cell polarity, tissue size and cell adhesion. In humans, DCHS1 mutations cause pleiotropic Van Maldergem syndrome. Here, we report that mutations in zebrafish dchs1b and dchs2 disrupt several aspects of embryogenesis, including gastrulation. Unexpectedly, maternal zygotic (MZ) dchs1b mutants show defects in the earliest developmental stage, egg activation, including abnormal cortical granule exocytosis (CGE), cytoplasmic segregation, cleavages and maternal mRNA translocation, in transcriptionally quiescent embryos. Later, MZdchs1b mutants exhibit altered dorsal organizer and mesendodermal gene expression, due to impaired dorsal determinant transport and Nodal signaling. Mechanistically, MZdchs1b phenotypes can be explained in part by defective actin or microtubule networks, which appear bundled in mutants. Accordingly, disruption of actin cytoskeleton in wild-type embryos phenocopied MZdchs1b mutant defects in cytoplasmic segregation and CGE, whereas interfering with microtubules in wild-type embryos impaired dorsal organizer and mesodermal gene expression without perceptible earlier phenotypes. Moreover, the bundled microtubule phenotype was partially rescued by expressing either full-length Dchs1b or its intracellular domain, suggesting that Dchs1b affects microtubules and some developmental processes independent of its known ligand Fat. Our results indicate novel roles for vertebrate Dchs in actin and microtubule cytoskeleton regulation in the unanticipated context of the single-celled embryo. PMID:26160902

  18. Acid stress mediated adaptive divergence in ion channel function during embryogenesis in Rana arvalis

    PubMed Central

    Shu, Longfei; Laurila, Anssi; Räsänen, Katja

    2015-01-01

    Ion channels and pumps are responsible for ion flux in cells, and are key mechanisms mediating cellular function. Many environmental stressors, such as salinity and acidification, are known to severely disrupt ionic balance of organisms thereby challenging fitness of natural populations. Although ion channels can have several vital functions during early life-stages (e.g. embryogenesis), it is currently not known i) how developing embryos maintain proper intracellular conditions when exposed to environmental stress and ii) to what extent environmental stress can drive intra-specific divergence in ion channels. Here we studied the moor frog, Rana arvalis, from three divergent populations to investigate the role of different ion channels and pumps for embryonic survival under acid stress (pH 4 vs 7.5) and whether populations adapted to contrasting acidities differ in the relative role of different ion channel/pumps. We found that ion channels that mediate Ca2+ influx are essential for embryonic survival under acidic pH, and, intriguingly, that populations differ in calcium channel function. Our results suggest that adaptive divergence in embryonic acid stress tolerance of amphibians may in part be mediated by Ca2+ balance. We suggest that ion flux may mediate adaptive divergence of natural populations at early life-stages in the face of environmental stress. PMID:26381453

  19. Morphogenetic fields in embryogenesis, regeneration, and cancer: Non-local control of complex patterning

    PubMed Central

    Levin, Michael

    2012-01-01

    Establishment of shape during embryonic development, and the maintenance of shape against injury or tumorigenesis, requires constant coordination of cell behaviors toward the patterning needs of the host organism. Molecular cell biology and genetics have made great strides in understanding the mechanisms that regulate cell function. However, generalized rational control of shape is still largely beyond our current capabilities. Significant instructive signals function at long range to provide positional information and other cues to regulate organism-wide systems properties like anatomical polarity and size control. Is complex morphogenesis best understood as the emergent property of local cell interactions, or as the outcome of a computational process that is guided by a physically-encoded map or template of the final goal state? Here I review recent data and molecular mechanisms relevant to morphogenetic fields: large-scale systems of physical properties that have been proposed to store patterning information during embryogenesis, regenerative repair, and cancer suppression that ultimately controls anatomy. Placing special emphasis on the role of endogenous bioelectric signals as an important component of the morphogenetic field, I speculate on novel approaches for the computational modeling and control of these fields with applications to synthetic biology, regenerative medicine, and evolutionary developmental biology. PMID:22542702

  20. Somatic deletions implicated in functional diversity of brain cells of individuals with schizophrenia and unaffected controls

    PubMed Central

    Kim, Junho; Shin, Jong-Yeon; Kim, Jong-Il; Seo, Jeong-Sun; Webster, Maree J.; Lee, Doheon; Kim, Sanghyeon

    2014-01-01

    While somatic DNA copy number variations (CNVs) have been identified in multiple tissues from normal people, they have not been well studied in brain tissues from individuals with psychiatric disorders. With ultrahigh depth sequencing data, we developed an integrated pipeline for calling somatic deletions using data from multiple tissues of the same individual or a single tissue type taken from multiple individuals. Using the pipelines, we identified 106 somatic deletions in DNA from prefrontal cortex (PFC) and/or cerebellum of two normal controls subjects and/or three individuals with schizophrenia. We then validated somatic deletions in 18 genic and in 1 intergenic region. Somatic deletions in BOD1 and CBX3 were reconfirmed using DNA isolated from non-pyramidal neurons and from cells in white matter using laser capture microdissection (LCM). Our results suggest that somatic deletions may affect metabolic processes and brain development in a region specific manner. PMID:24448323

  1. Iteration, Not Induction

    ERIC Educational Resources Information Center

    Dobbs, David E.

    2009-01-01

    The main purpose of this note is to present and justify proof via iteration as an intuitive, creative and empowering method that is often available and preferable as an alternative to proofs via either mathematical induction or the well-ordering principle. The method of iteration depends only on the fact that any strictly decreasing sequence of…

  2. Using Continuity Induction

    ERIC Educational Resources Information Center

    Hathaway, Dan

    2011-01-01

    Here is a technique for proving the fundamental theorems of analysis that provides a unified way to pass from local properties to global properties on the real line, just as ordinary induction passes from local implication (if true for "k", the theorem is true for "k" + 1) to a global conclusion in the natural numbers.

  3. Metallic induction reaction engine

    NASA Astrophysics Data System (ADS)

    Hart, Douglas; Mongeau, Peter P.; Kolm, Henry H.

    1985-11-01

    Metal rings placed close to a pulsed field coil have been accelerated at 200 million gee to 5 km/s in a 2 cm length by Bandoletov in the USSR Bandoletov, 1977. We have studied the basic phenomena and ultimate limitations of the pulsed induction process both theoretically and experimentally to determine its usefulness as a reaction engine. It is possible in principle to accelerate metal rings at high efficiency, and impart sufficient energy to ensure melting and evaporation, so that the reaction mass is ultimately ejected in the form of plasma. In practice the process is limited by electrical, mechanical and thermal failure of the induction coil. Over a hundred shots were fired including several in which 12 gram rings were accelerated to over 700 m/s at efficiencies above 30 percent. This is equivalent to the performance of a high power rifle with a one inch long barrel. An unexpected result of these studies is the discovery that to achieve maximum velocity, the mutual inductance gradient between induction coil and projectile ring in the firing position must be reduced to minimize the initial acceleration. This reduces the back voltage and increases the interaction time, resulting in maximum energy transfer.

  4. Educational Inductive Gravimeter

    ERIC Educational Resources Information Center

    Nunn, John

    2014-01-01

    A simple inductive gravimeter constructed from a rigid plastic pipe and insulated copper wire is described. When a magnet is dropped through the vertically mounted pipe it induces small alternating voltages. These small signals are fed to the microphone input of a typical computer and sampled at a typical rate of 44.1 kHz using a custom computer…

  5. From “Directed Differentiation” to “Neuronal Induction”: Modeling Neuropsychiatric Disease

    PubMed Central

    Ho, Seok-Man; Topol, Aaron; Brennand, Kristen J

    2015-01-01

    Aberrant behavior and function of neurons are believed to be the primary causes of most neurological diseases and psychiatric disorders. Human postmortem samples have limited availability and, while they provide clues to the state of the brain after a prolonged illness, they offer limited insight into the factors contributing to disease onset. Conversely, animal models cannot recapitulate the polygenic origins of neuropsychiatric disease. Novel methods, such as somatic cell reprogramming, deliver nearly limitless numbers of pathogenic human neurons for the study of the mechanism of neuropsychiatric disease initiation and progression. First, this article reviews the advent of human induced pluripotent stem cell (hiPSC) technology and introduces two major methods, “directed differentiation” and “neuronal induction,” by which it is now possible to generate neurons for modeling neuropsychiatric disease. Second, it discusses the recent applications, and the limitations, of these technologies to in vitro studies of psychiatric disorders. PMID:26045654

  6. Inductive Reasoning: A Training Approach

    ERIC Educational Resources Information Center

    Klauer, Karl Josef; Phye, Gary D.

    2008-01-01

    Researchers have examined inductive reasoning to identify different cognitive processes when participants deal with inductive problems. This article presents a prescriptive theory of inductive reasoning that identifies cognitive processing using a procedural strategy for making comparisons. It is hypothesized that training in the use of the…

  7. RESTRICTION SEMIGROUPS AND INDUCTIVE CONSTELLATIONS

    E-print Network

    Gould, Victoria

    RESTRICTION SEMIGROUPS AND INDUCTIVE CONSTELLATIONS VICTORIA GOULD AND CHRISTOPHER HOLLINGS with appropriate morphisms, is isomorphic to a category of partial semigroups we dub inductive constellations a theory of partial action and expansion for inductive constellations, along the lines of that of Gilbert

  8. Transition from somatic embryo to friable embryogenic callus in cassava: dynamic changes in cellular structure, physiological status, and gene expression profiles

    PubMed Central

    Ma, Qiuxiang; Zhou, Wenzhi; Zhang, Peng

    2015-01-01

    Friable embryogenic callus (FEC) is considered as the most suitable material for efficient genetic transformation of cassava. Heavy genotype dependence of FEC induction and amenability to somaclonal variation limits the production and maintenance of reliable FEC. Identifying key elements involved in biological processes from somatic embryos (SEs) to FEC at different stages provides critical insights for FEC improvement. Cytological observation showed a dramatic change of subcellular structures among SEs, fresh FEC (FFEC), and old FEC (OFEC). Decrease of sucrose and increase of fructose and glucose were detected in OFEC. A total of 6871 differentially expressed genes (DEGs) were identified from SEs, FFEC, and OFEC by RNA-seq. Analysis of the DEGs showed that FEC induction was accompanied by the process of dedifferentiation, whereas the epigenetics modification occurred during the continuous subculturing process. The cell structure was reconstructed, mainly including the GO terms of “cell periphery” and “external encapsulating structure”; in parallel, the internal mechanisms changed correspondingly, including the biological process of glycolysis and metabolisms of alanine, aspartate, and glutamate. The significant reduction of genomic DNA methylation in OFEC indicated altered gene expression via chromatin modification. These results indicate that the induction and long-term subculture of FEC is a complicated biological process involving changes of genome modification, gene expression, and subcellular reconstruction. The findings will be useful for improving FEC induction and maintenance from farmer-preferred cassava cultivars recalcitrant to genetic transformation, hence improving cassava through genetic engineering. PMID:26500668

  9. Transition from somatic embryo to friable embryogenic callus in cassava: dynamic changes in cellular structure, physiological status, and gene expression profiles.

    PubMed

    Ma, Qiuxiang; Zhou, Wenzhi; Zhang, Peng

    2015-01-01

    Friable embryogenic callus (FEC) is considered as the most suitable material for efficient genetic transformation of cassava. Heavy genotype dependence of FEC induction and amenability to somaclonal variation limits the production and maintenance of reliable FEC. Identifying key elements involved in biological processes from somatic embryos (SEs) to FEC at different stages provides critical insights for FEC improvement. Cytological observation showed a dramatic change of subcellular structures among SEs, fresh FEC (FFEC), and old FEC (OFEC). Decrease of sucrose and increase of fructose and glucose were detected in OFEC. A total of 6871 differentially expressed genes (DEGs) were identified from SEs, FFEC, and OFEC by RNA-seq. Analysis of the DEGs showed that FEC induction was accompanied by the process of dedifferentiation, whereas the epigenetics modification occurred during the continuous subculturing process. The cell structure was reconstructed, mainly including the GO terms of "cell periphery" and "external encapsulating structure"; in parallel, the internal mechanisms changed correspondingly, including the biological process of glycolysis and metabolisms of alanine, aspartate, and glutamate. The significant reduction of genomic DNA methylation in OFEC indicated altered gene expression via chromatin modification. These results indicate that the induction and long-term subculture of FEC is a complicated biological process involving changes of genome modification, gene expression, and subcellular reconstruction. The findings will be useful for improving FEC induction and maintenance from farmer-preferred cassava cultivars recalcitrant to genetic transformation, hence improving cassava through genetic engineering. PMID:26500668

  10. Somatic amplifications and deletions in genome of papillary thyroid carcinomas.

    PubMed

    Passon, Nadia; Bregant, Elisa; Sponziello, Marialuisa; Dima, Maria; Rosignolo, Francesca; Durante, Cosimo; Celano, Marilena; Russo, Diego; Filetti, Sebastiano; Damante, Giuseppe

    2015-11-01

    Somatic gene copy number variation contributes to tumor progression. Using comparative genomic hybridization (CGH) array, the presence of genomic imbalances was evaluated in a series of 27 papillary thyroid carcinomas (PTCs). To detect only somatic imbalances, for each sample, the reference DNA was from normal thyroid tissue of the same patient. The presence of the BRAF V600E mutation was also evaluated. Both amplifications and deletions showed an uneven distribution along the entire PTC cohort; amplifications were more frequent than deletions (mean values of 17.5 and 7.2, respectively). Number of aberration events was not even among samples, the majority of them occurring only in a small fraction of PTCs. Most frequent amplifications were detected at regions 2q35, 4q26, and 4q34.1, containing FN1, PDE5A, and GALNTL6 genes, respectively. Most frequent deletions occurred at regions 6q25.2, containing OPMR1 and IPCEF1 genes and 7q14.2, containing AOAH and ELMO1 genes. Amplification of FN1 and PDE5A genomic regions was confirmed by quantitative PCR. Frequency of amplifications and deletions was in relationship with clinical features and BRAF mutation status of tumor. In fact, according to the American Joint Committee on Cancer stage and American Thyroid Association (ATA) risk classification, amplifications are more frequent in higher risk samples, while deletions tend to prevail in the lower risk tumors. Analysis of single aberrations according to the ATA risk grouping shows that amplifications containing PDE5A, GALNTL6, DHRS3, and DOCK9 genes are significantly more frequent in the intermediate/high risk group than in the low risk group. Thus, our data would indicate that analysis of somatic genome aberrations by CGH array can be useful to identify additional prognostic variables. PMID:25863487

  11. Somatic second-hit mutations leads to polycystic liver diseases.

    PubMed

    Banales, Jesús M; Munoz-Garrido, Patricia; Bujanda, Luis

    2013-01-01

    Polycystic liver diseases (PCLDs) are a heterogeneous group of genetic disorders characterized by the development of multiple fluid-filled cysts in the liver, which derive from cholangiocytes, the epithelial cells lining the bile ducts. When these cysts grow, symptoms such as abdominal distension, nausea, and abdominal pain may occur. PCLDs may exist isolated (i.e., autosomal dominant polycystic liver disease, ADPLD) or in combination with renal cystogenesis (i.e., autosomal dominant polycystic kidney disease and autosomal recessive polycystic liver disease). The exact prevalence of PCLDs is unknown, but is estimated to occur in approximately 1:1000 persons. Although the pathogenesis of each form of PCLD appears to be different, increasing evidences indicate that hepatic cystogenesis is a phenomenon that may involve somatic loss of heterozygosity (LOH) in those pathological conditions inherited in a dominant form. A recent report, using highly sophisticated methodology, demonstrated that ADPLD patients with a germline mutation in the protein kinase C substrate 80K-H (PRKCSH) gene mostly develop hepatic cystogenesis through a second somatic mutation. While hepatocystin, the PRKCSH-encoding protein, was absent in the hepatic cysts with LOH, it was still expressed in the heterozygous cysts. On the other hand, no additional trans-heterozygous mutations on the SEC63 homolog (S. cerevisiae/SEC63) gene (also involved in the development of PCLDs) were observed. These data indicate that PCLD is recessive at the cellular level, and point out the important role of hepatocystin loss in cystogenesis. In this commentary, we discuss the knowledge regarding the role of somatic second-hit mutations in the development of PCLDs, and the most relevant findings have been highlighted. PMID:23326178

  12. Germ-line and somatic DICER1 mutations in pineoblastoma

    PubMed Central

    de Kock, Leanne; Sabbaghian, Nelly; Druker, Harriet; Weber, Evan; Hamel, Nancy; Miller, Suzanne; Choong, Catherine S.; Gottardo, Nicholas G.; Kees, Ursula R.; Rednam, Surya P.; van Hest, Liselotte P.; Jongmans, Marjolijn C.; Jhangiani, Shalini; Lupski, James R.; Zacharin, Margaret; Bouron-Dal Soglio, Dorothée; Huang, Annie; Priest, John R.; Perry, Arie; Mueller, Sabine; Albrecht, Steffen; Malkin, David; Grundy, Richard G.

    2015-01-01

    Germ-line RB-1 mutations predispose to pineoblastoma (PinB), but other predisposing genetic factors are not well established. We recently identifed a germ-line DICER1 mutation in a child with a PinB. This was accompanied by loss of heterozygosity (LOH) of the wild-type allele within the tumour. We set out to establish the prevalence of DICER1 mutations in an opportunistically ascertained series of PinBs. Twenty-one PinB cases were studied: eighteen cases had not undergone previous testing for DICER1 mutations; three patients were known carriers of germ-line DICER1 mutations. The eighteen PinBs were sequenced by Sanger and/or Fluidigm-based next-generation sequencing to identify DICER1 mutations in blood gDNA and/or tumour gDNA. Testing for somatic DICER1 mutations was also conducted on one case with a known germ-line DICER1 mutation. From the eighteen PinBs, we identified four deleterious DICER1 mutations, three of which were germ line in origin, and one for which a germ line versus somatic origin could not be determined; in all four, the second allele was also inactivated leading to complete loss of DICER1 protein. No somatic DICER1 RNase IIIb mutations were identified. One PinB arising in a germ-line DICER1 mutation carrier was found to have LOH. This study suggests that germ-line DICER1 mutations make a clinically significant contribution to PinB, establishing DICER1 as an important susceptibility gene for PinB and demonstrates PinB to be a manifestation of a germ-line DICER1 mutation. The means by which the second allele is inactivated may differ from other DICER1-related tumours. PMID:25022261

  13. A somatic gene rearrangement contributing to genetic diversity in maize

    SciTech Connect

    Das, O.P.; Levi-Minzi, S.; Koury, M.; Benner, M.; Messing, J. )

    1990-10-01

    The authors have discovered a somatic genomic rearrangement that occurs at high frequency at a duplicated zein locus in certain cultures of the maize inbred line A188. The rearranged allele arises from the duplication by a two-step process involving a homologous recombination and a second event, which may be a deletion, inversion, or insertion; both steps always occur together. The frequency of rearrangement is lower in homozygous states of the parental allele than in heterozygotes. In both cases, the rearrangement is shown to be mitotic. The rearranged product can be transmitted through meiosis, providing another mechanism for genome evolution in higher eukaryotes.

  14. Environmental epigenetic transgenerational inheritance and somatic epigenetic mitotic stability.

    PubMed

    Skinner, Michael K

    2011-07-01

    The majority of environmental factors can not modify DNA sequence, but can influence the epigenome. The mitotic stability of the epigenome and ability of environmental epigenetics to influence phenotypic variation and disease, suggests environmental epigenetics will have a critical role in disease etiology and biological areas such as evolutionary biology. The current review presents the molecular basis of how environment can promote stable epigenomes and modified phenotypes, and distinguishes the difference between epigenetic transgenerational inheritance through the germ line versus somatic cell mitotic stability. PMID:21637037

  15. Somatic thrombopoietin (THPO) gene mutations in childhood myeloid leukemias.

    PubMed

    Houwing, Maite E; Koopman-Coenen, Eva A; Kersseboom, Rogier; Gooskens, Saskia; Appel, Inge M; Arentsen-Peters, Susan T C J M; de Vries, Andrica C H; Reinhardt, Dirk; Stary, Jan; Baruchel, André; de Haas, Valerie; Blink, Marjolein; Lopes Cardozo, Rob H; Pieters, Rob; Michel Zwaan, C; van den Heuvel-Eibrink, Marry M

    2015-07-01

    We report, for the first time, a non-syndromic infant with a reversible myeloproliferative disease that harbors a germline hereditary thrombopoietin (THPO) gene mutation, a condition that is known to induce familial thrombocytosis at increasing age. In order to investigate whether somatic THPO gene mutations play a role in sporadic pediatric myeloproliferative diseases, we performed a mutation screening of a large representative cohort of pediatric acute myeloid leukemia, myeloid leukemia of Down syndrome, and juvenile myelomonocytic leukemia samples and show that gain-of-function THPO mutations are extremely rare in sporadic pediatric myeloproliferative diseases. PMID:25728710

  16. Mosaicism: The embryo as a target for induction of mutations leading to cancer and genetic disease

    SciTech Connect

    Mohrenweiser, H.; Zingg, B.

    1995-12-31

    Mosaicismhas been observed in both germinal and somatic tissues of several species, including humans. Mutational events occurring during early embryogenesis can give rise to an organism with a significant number of cells with the mutant genotype in one or more tissues. In the F{sub 1} generation, this event will usually be perceived as a de novo germinal mutation rather than a transmitted variant allele, unless significant effort is directed toward detecting the mosaicism. Similarly, mutations in oncogenes and tumor-suppressor genes in proliferating somatic cells can generate populations of cells that are at increased risk of transforming into tumor cells. The number of potential preneoplastic cells is larger when the mutagenic event occurs in early development than if it occurs in the mature adult. Experimental data confirm that treatment of the developing embryo or fetus with carcinogenic and mutagenic agents increases the cancer incidence in these animals and the frequency of mutations in the offspring of the animals that were exposed in utero. The available data are conclusive that the developing organism is at risk from exposure to mutagenic and carcinogenic agents. However, the data are insufficient to estimate the level of risk associated with similar exposures to the adult organism. The potential risk from exposure of the developing embryo is increased relative to the risk from adult exposure if the sensitivity of the individual cells to damage in the adult and the embryo are equivalent. It seems apparent that the potential risks of cancer and heritable disease following in utero exposure are sufficient to warrant additional attention. It is important to obtain data for estimating the relative contribution of in utero exposure to mutagenic and carcinogenic agents to the total health burden and for the subsequent development of appropriate regulations. 60 refs., 2 figs.

  17. Inductive Position Sensor

    NASA Technical Reports Server (NTRS)

    Youngquist, Robert C. (Inventor); Simmons, Stephen M. (Inventor)

    2015-01-01

    An inductive position sensor uses three independent inductors inductively coupled by a common medium such as air. First and second inductors are separated by a fixed distance with the first inductor's axial core and second inductor's axial core maintained parallel to one another. A third inductor is disposed between the first and second inductors with the third inductor's axial core being maintained parallel to those of the first and second inductors. The combination of the first and second inductors are configured for relative movement with the third inductor's axial core remaining parallel to those of the first and second inductors as distance changes from the third inductor to each of the first inductor and second inductor. An oscillating current can be supplied to at least one of the three inductors, while voltage induced in at least one of the three inductors not supplied with the oscillating current is measured.

  18. Superconducting kinetic inductance radiometer

    SciTech Connect

    Sauvageau, J.E.; McDonald, D.G.; Grossman, E.N. )

    1991-03-01

    We are developing a bolometer based on a differential thermometer that senses temperature changes through changes in the kinetic inductance of a superconducting thin film. The temperature transducer is an inductance bridge patterned as an integrated circuit on a 1 cm{sup 2} Si substrate. Two inductors from opposite arms of the bridge are patterned on a 2 mm{sup 2} thermally isolated Si island which is supported by a 9 {mu}m thick Si:B membrane. The bridge is excited with audio frequency current and the bridge imbalance is detected with a commercial DC SQUID amplifier. The bridge is balanced by applying power to the thermally isolated island. This thermometer is the sensor for a prototype radiometer that will provide an absolute measure of IR power.

  19. Induction plasma tube

    DOEpatents

    Hull, D.E.

    1982-07-02

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  20. Induction plasma tube

    DOEpatents

    Hull, Donald E. (Los Alamos, NM)

    1984-01-01

    An induction plasma tube having a segmented, fluid-cooled internal radiation shield is disclosed. The individual segments are thick in cross-section such that the shield occupies a substantial fraction of the internal volume of the plasma enclosure, resulting in improved performance and higher sustainable plasma temperatures. The individual segments of the shield are preferably cooled by means of a counterflow fluid cooling system wherein each segment includes a central bore and a fluid supply tube extending into the bore. The counterflow cooling system results in improved cooling of the individual segments and also permits use of relatively larger shield segments which permit improved electromagnetic coupling between the induction coil and a plasma located inside the shield. Four embodiments of the invention, each having particular advantages, are disclosed.

  1. Induction motor control

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1990-01-01

    Electromechanical actuators developed to date have commonly ultilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilized induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high-frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high-frequency power distribution and management techniques developed by NASA for Space Station Freedom.

  2. Induction motor control

    NASA Technical Reports Server (NTRS)

    Hansen, Irving G.

    1990-01-01

    Electromechanical actuators developed to date have commonly utilized permanent magnet (PM) synchronous motors. More recently switched reluctance (SR) motors have been advocated due to their robust characteristics. Implications of work which utilizes induction motors and advanced control techniques are discussed. When induction motors are operated from an energy source capable of controlling voltages and frequencies independently, drive characteristics are obtained which are superior to either PM or SR motors. By synthesizing the machine frequency from a high frequency carrier (nominally 20 kHz), high efficiencies, low distortion, and rapid torque response are available. At this time multiple horsepower machine drives were demonstrated, and work is on-going to develop a 20 hp average, 40 hp peak class of aerospace actuators. This effort is based upon high frequency power distribution and management techniques developed by NASA for Space Station Freedom.

  3. Personality traits influencing somatization symptoms and social inhibition in the elderly

    PubMed Central

    Wongpakaran, Tinakon; Wongpakaran, Nahathai

    2014-01-01

    Purpose Somatization is a common symptom among the elderly, and even though personality disorders have been found to be associated with somatization, personality traits have not yet been explored with regard to this symptom. The aim of this study is to investigate the relationship between personality traits and somatization, and social inhibition. Patients and methods As part of a cross-sectional study of a community sample, 126 elderly Thais aged 60 years or over completed self-reporting questionnaires related to somatization and personality traits. Somatization was elicited from the somatization subscale when using the Symptom Checklist SCL-90 instrument. Personality traits were drawn from the 16 Personality Factor Questionnaire and social inhibition was identified when using the inventory of interpersonal problems. In addition, path analysis was used to establish the influence of personality traits on somatization and social inhibition. Results Of the 126 participants, 51% were male, 55% were married, and 25% were retired. The average number of years in education was 7.6 (standard deviation =5.2). “Emotional stability” and “dominance” were found to have a direct effect on somatization, as were age and number of years in education, but not sex. Also, 35% of the total variance could be explained by the model, with excellent fit statistics. Dominance was found to have an indirect effect, via vigilance, on social inhibition, which was also influenced by number of years in education and emotional stability. Social inhibition was not found to have any effect on somatization, although hypothetically it should. Conclusion “Emotional stability”, “dominance”, and “vigilance”, as well as age and the number of years in education, were found to have an effect on somatization. Attention should be paid to these factors in the elderly with somatization. PMID:24477217

  4. Diagnostics for induction accelerators

    SciTech Connect

    Fessenden, T.J.

    1996-04-01

    The induction accelerator was conceived by N. C. Christofilos and first realized as the Astron accelerator that operated at LLNL from the early 1960`s to the end of 1975. This accelerator generated electron beams at energies near 6 MeV with typical currents of 600 Amperes in 400 ns pulses. The Advanced Test Accelerator (ATA) built at Livermore`s Site 300 produced 10,000 Ampere beams with pulse widths of 70 ns at energies approaching 50 MeV. Several other electron and ion induction accelerators have been fabricated at LLNL and LBNL. This paper reviews the principal diagnostics developed through efforts by scientists at both laboratories for measuring the current, position, energy, and emittance of beams generated by these high current, short pulse accelerators. Many of these diagnostics are closely related to those developed for other accelerators. However, the very fast and intense current pulses often require special diagnostic techniques and considerations. The physics and design of the more unique diagnostics developed for electron induction accelerators are presented and discussed in detail.

  5. Spatial anisotropies and temporal fluctuations in extracellular matrix network texture during early embryogenesis.

    PubMed

    Loganathan, Rajprasad; Potetz, Brian R; Rongish, Brenda J; Little, Charles D

    2012-01-01

    Early stages of vertebrate embryogenesis are characterized by a remarkable series of shape changes. The resulting morphological complexity is driven by molecular, cellular, and tissue-scale biophysical alterations. Operating at the cellular level, extracellular matrix (ECM) networks facilitate cell motility. At the tissue level, ECM networks provide material properties required to accommodate the large-scale deformations and forces that shape amniote embryos. In other words, the primordial biomaterial from which reptilian, avian, and mammalian embryos are molded is a dynamic composite comprised of cells and ECM. Despite its central importance during early morphogenesis we know little about the intrinsic micrometer-scale surface properties of primordial ECM networks. Here we computed, using avian embryos, five textural properties of fluorescently tagged ECM networks--(a) inertia, (b) correlation, (c) uniformity, (d) homogeneity, and (e) entropy. We analyzed fibronectin and fibrillin-2 as examples of fibrous ECM constituents. Our quantitative data demonstrated differences in the surface texture between the fibronectin and fibrillin-2 network in Day 1 (gastrulating) embryos, with the fibronectin network being relatively coarse compared to the fibrillin-2 network. Stage-specific regional anisotropy in fibronectin texture was also discovered. Relatively smooth fibronectin texture was exhibited in medial regions adjoining the primitive streak (PS) compared with the fibronectin network investing the lateral plate mesoderm (LPM), at embryonic stage 5. However, the texture differences had changed by embryonic stage 6, with the LPM fibronectin network exhibiting a relatively smooth texture compared with the medial PS-oriented network. Our data identify, and partially characterize, stage-specific regional anisotropy of fibronectin texture within tissues of a warm-blooded embryo. The data suggest that changes in ECM textural properties reflect orderly time-dependent rearrangements of a primordial biomaterial. We conclude that the ECM microenvironment changes markedly in time and space during the most important period of amniote morphogenesis--as determined by fluctuating textural properties. PMID:22693609

  6. Sex steroid dynamics during embryogenesis and sexual differentiation in Eurasian perch, Perca fluviatilis.

    PubMed

    Rougeot, C; Krim, A; Mandiki, S N M; Kestemont, P; Mélard, C

    2007-03-15

    It is widely accepted that sex steroid hormones play an important and a specific role during the process of sex differentiation in fish. In order to describe the role of the three main sex steroid hormones (testosterone--T, 17beta-estradiol--E2 and 11keto-testosterone--11KT) during embryogenesis and sex differentiation in Eurasian perch, Perca fluviatilis, eggs, larvae and juveniles originating from two mixed-sex and two all-female progenies were regularly sampled from fertilization to hatching (D0) and from hatching to day 70 post-hatching (D70). Just after spawning, a significant amount of sex steroids [T (1634.2pgg(-1)), E2 (554.4pgg(-1)) and 11KT (1513.2pgg(-1))] was measured in non-fertilised eggs suggesting a maternal transmission of these steroids. From D2 to D70 post-hatching, E2 levels were significantly higher in mixed-sex progenies (median: 725.7pgg(-1)) than in all-female progenies (156.2pgg(-1)) and significantly increased after the onset of the histological differentiation of the gonad in both progenies (D35). Levels of 11KT were significantly higher in mixed-sex (median: 431.5pgg(-1)) than in all-female progenies (below the limit of assay detection) and significantly increased at D35 in all-female progenies (median value: 343.2pgg(-1)). Mean 11KT to E2 ratio was six-fold higher in mixed-sex progenies (1.35) than in all-female progenies (0.24). The data suggest that the 11-oxygenated androgen (11KT) plays a major role in the male differentiation process, and that sex differentiation in Eurasian perch is probably determined by the 11KT to E2 ratio. PMID:17270265

  7. Enhancer of zeste acts as a major developmental regulator of Ciona intestinalis embryogenesis

    PubMed Central

    Le Goff, Emilie; Martinand-Mari, Camille; Martin, Marianne; Feuillard, Jérôme; Boublik, Yvan; Godefroy, Nelly; Mangeat, Paul; Baghdiguian, Stephen; Cavalli, Giacomo

    2015-01-01

    ABSTRACT The paradigm of developmental regulation by Polycomb group (PcG) proteins posits that they maintain silencing outside the spatial expression domains of their target genes, particularly of Hox genes, starting from mid embryogenesis. The Enhancer of zeste [E(z)] PcG protein is the catalytic subunit of the PRC2 complex, which silences its targets via deposition of the H3K27me3 mark. Here, we studied the ascidian Ciona intestinalis counterpart of E(z). Ci-E(z) is detected by immunohistochemistry as soon as the 2- and 4-cell stages as a cytoplasmic form and becomes exclusively nuclear thereafter, whereas the H3K27me3 mark is detected starting from the gastrula stage and later. Morpholino invalidation of Ci-E(z) leads to the total disappearance of both Ci-E(z) protein and its H3K27me3 mark. Ci-E(z) morphants display a severe phenotype. Strikingly, the earliest defects occur at the 4-cell stage with the dysregulation of cell positioning and mitotic impairment. At later stages, Ci-E(z)-deficient embryos are affected by terminal differentiation defects of neural, epidermal and muscle tissues, by the failure to form a notochord and by the absence of caudal nerve. These major phenotypic defects are specifically rescued by injection of a morpholino-resistant Ci-E(z) mRNA, which restores expression of Ci-E(z) protein and re-deposition of the H3K27me3 mark. As observed by qPCR analyses, Ci-E(z) invalidation leads to the early derepression of tissue-specific developmental genes, whereas late-acting developmental genes are generally down-regulated. Altogether, our results suggest that Ci-E(z) plays a major role during embryonic development in Ciona intestinalis by silencing early-acting developmental genes in a Hox-independent manner. PMID:26276097

  8. Tissue-specific SMARCA4 binding at active and repressed regulatory elements during embryogenesis.

    PubMed

    Attanasio, Catia; Nord, Alex S; Zhu, Yiwen; Blow, Matthew J; Biddie, Simon C; Mendenhall, Eric M; Dixon, Jesse; Wright, Crystal; Hosseini, Roya; Akiyama, Jennifer A; Holt, Amy; Plajzer-Frick, Ingrid; Shoukry, Malak; Afzal, Veena; Ren, Bing; Bernstein, Bradley E; Rubin, Edward M; Visel, Axel; Pennacchio, Len A

    2014-06-01

    The SMARCA4 (also known as BRG1 in humans) chromatin remodeling factor is critical for establishing lineage-specific chromatin states during early mammalian development. However, the role of SMARCA4 in tissue-specific gene regulation during embryogenesis remains poorly defined. To investigate the genome-wide binding landscape of SMARCA4 in differentiating tissues, we engineered a Smarca4(FLAG) knock-in mouse line. Using ChIP-seq, we identified ?51,000 SMARCA4-associated regions across six embryonic mouse tissues (forebrain, hindbrain, neural tube, heart, limb, and face) at mid-gestation (E11.5). The majority of these regions was distal from promoters and showed dynamic occupancy, with most distal SMARCA4 sites (73%) confined to a single or limited subset of tissues. To further characterize these regions, we profiled active and repressive histone marks in the same tissues and examined the intersection of informative chromatin states and SMARCA4 binding. This revealed distinct classes of distal SMARCA4-associated elements characterized by activating and repressive chromatin signatures that were associated with tissue-specific up- or down-regulation of gene expression and relevant active/repressed biological pathways. We further demonstrate the predicted active regulatory properties of SMARCA4-associated elements by retrospective analysis of tissue-specific enhancers and direct testing of SMARCA4-bound regions in transgenic mouse assays. Our results indicate a dual active/repressive function of SMARCA4 at distal regulatory sequences in vivo and support its role in tissue-specific gene regulation during embryonic development. PMID:24752179

  9. Zfyve9a regulates the proliferation of hepatic cells during zebrafish embryogenesis.

    PubMed

    Liu, Nian; Li, Zhuo; Pei, Duanqing; Shu, Xiaodong

    2013-01-01

    Zfyve9 is a FYVE domain protein first identified as a binding partner for SMAD2/3. In vitro studies indicate that it can function either positively or negatively in the TGF-beta signaling pathway depending on the cell lines used. However, the in vivo function of this protein remains to be investigated. We first analyzed the tissue distribution of zebrafish zfyve9a by in situ hybridization. To investigate the in vivo function of this gene, we performed morpholino mediated loss-of-function assays. We analyzed the expression patterns of liver (cp and fabp10a), pancreas (trypsin and insulin) or gut (fabp2) specific markers to determine whether the formation of these organs is affected by zfyve9a knockdown. We determined the specification of hepatoblast in the zfyve9a morphants (prox1a) and investigated the proliferation and survival of hepatic cells in the morphants by P-H3 staining and TUNEL assay respectively. We report here that zfyve9a is enriched in the zebrafish embryonic liver and required for hepatogenesis. Morpholino mediated knockdown of zfyve9a inhibits the formation of liver by day 4 while the other endoderm-derived organs appear unaffected. We demonstrated that the specification of hepatoblasts is normal in the zfyve9a morphants; however, the proliferation rate of these cells is reduced. Thus, our results reveal the liver-specific function of zfyve9a during early embryogenesis and indicate that the zfyve9a mediated signal is essential for the proliferation of hepatic cells during the expansion of liver bud. PMID:24307302

  10. Spatial Anisotropies and Temporal Fluctuations in Extracellular Matrix Network Texture during Early Embryogenesis

    PubMed Central

    Loganathan, Rajprasad; Potetz, Brian R.; Rongish, Brenda J.; Little, Charles D.

    2012-01-01

    Early stages of vertebrate embryogenesis are characterized by a remarkable series of shape changes. The resulting morphological complexity is driven by molecular, cellular, and tissue-scale biophysical alterations. Operating at the cellular level, extracellular matrix (ECM) networks facilitate cell motility. At the tissue level, ECM networks provide material properties required to accommodate the large-scale deformations and forces that shape amniote embryos. In other words, the primordial biomaterial from which reptilian, avian, and mammalian embryos are molded is a dynamic composite comprised of cells and ECM. Despite its central importance during early morphogenesis we know little about the intrinsic micrometer-scale surface properties of primordial ECM networks. Here we computed, using avian embryos, five textural properties of fluorescently tagged ECM networks — (a) inertia, (b) correlation, (c) uniformity, (d) homogeneity, and (e) entropy. We analyzed fibronectin and fibrillin-2 as examples of fibrous ECM constituents. Our quantitative data demonstrated differences in the surface texture between the fibronectin and fibrillin-2 network in Day 1 (gastrulating) embryos, with the fibronectin network being relatively coarse compared to the fibrillin-2 network. Stage-specific regional anisotropy in fibronectin texture was also discovered. Relatively smooth fibronectin texture was exhibited in medial regions adjoining the primitive streak (PS) compared with the fibronectin network investing the lateral plate mesoderm (LPM), at embryonic stage 5. However, the texture differences had changed by embryonic stage 6, with the LPM fibronectin network exhibiting a relatively smooth texture compared with the medial PS-oriented network. Our data identify, and partially characterize, stage-specific regional anisotropy of fibronectin texture within tissues of a warm-blooded embryo. The data suggest that changes in ECM textural properties reflect orderly time-dependent rearrangements of a primordial biomaterial. We conclude that the ECM microenvironment changes markedly in time and space during the most important period of amniote morphogenesis—as determined by fluctuating textural properties. PMID:22693609

  11. Vitamin C modulates TET1 function during somatic cell reprogramming.

    PubMed

    Chen, Jiekai; Guo, Lin; Zhang, Lei; Wu, Haoyu; Yang, Jiaqi; Liu, He; Wang, Xiaoshan; Hu, Xiao; Gu, Tianpeng; Zhou, Zhiwei; Liu, Jing; Liu, Jiadong; Wu, Hongling; Mao, Shi-Qing; Mo, Kunlun; Li, Yingying; Lai, Keyu; Qi, Jing; Yao, Hongjie; Pan, Guangjin; Xu, Guo-Liang; Pei, Duanqing

    2013-12-01

    Vitamin C, a micronutrient known for its anti-scurvy activity in humans, promotes the generation of induced pluripotent stem cells (iPSCs) through the activity of histone demethylating dioxygenases. TET hydroxylases are also dioxygenases implicated in active DNA demethylation. Here we report that TET1 either positively or negatively regulates somatic cell reprogramming depending on the absence or presence of vitamin C. TET1 deficiency enhances reprogramming, and its overexpression impairs reprogramming in the context of vitamin C by modulating the obligatory mesenchymal-to-epithelial transition (MET). In the absence of vitamin C, TET1 promotes somatic cell reprogramming independent of MET. Consistently, TET1 regulates 5-hydroxymethylcytosine (5hmC) formation at loci critical for MET in a vitamin C-dependent fashion. Our findings suggest that vitamin C has a vital role in determining the biological outcome of TET1 function at the cellular level. Given its benefit to human health, vitamin C should be investigated further for its role in epigenetic regulation. PMID:24162740

  12. Somatic Uniparental Isodisomy Explains Multifocality of Glomuvenous Malformations

    PubMed Central

    Amyere, Mustapha; Aerts, Virginie; Brouillard, Pascal; McIntyre, Brendan A.S.; Duhoux, François P.; Wassef, Michel; Enjolras, Odile; Mulliken, John B.; Devuyst, Olivier; Antoine-Poirel, Hélène; Boon, Laurence M.; Vikkula, Miikka

    2013-01-01

    Inherited vascular malformations are commonly autosomal dominantly inherited with high, but incomplete, penetrance; they often present as multiple lesions. We hypothesized that Knudson’s two-hit model could explain this multifocality and partial penetrance. We performed a systematic analysis of inherited glomuvenous malformations (GVMs) by using multiple approaches, including a sensitive allele-specific pairwise SNP-chip method. Overall, we identified 16 somatic mutations, most of which were not intragenic but were cases of acquired uniparental isodisomy (aUPID) involving chromosome 1p. The breakpoint of each aUPID is located in an A- and T-rich, high-DNA-flexibility region (1p13.1–1p12). This region corresponds to a possible new fragile site. Occurrences of these mutations render the inherited glomulin variant in 1p22.1 homozygous in the affected tissues without loss of genetic material. This finding demonstrates that a double hit is needed to trigger formation of a GVM. It also suggests that somatic UPID, only detectable by sensitive pairwise analysis in heterogeneous tissues, might be a common phenomenon in human cells. Thus, aUPID might play a role in the pathogenesis of various nonmalignant disorders and might explain local impaired function and/or clinical variability. Furthermore, these data suggest that pairwise analysis of blood and tissue, even on heterogeneous tissue, can be used for localizing double-hit mutations in disease-causing genes. PMID:23375657

  13. Somatization: social control and illness production in a religious cult.

    PubMed

    Kliger, R

    1994-06-01

    The aim of this ethnographic work is twofold: first, to document the specifics of the illness experience within the highly controlling milieu of a religious cult; second, to explore the connection between somatization and social control in this particular context. Anthropologists have long realized that in order to comprehend disease etiology, one must examine both biological and sociocultural processes, as both are implicated in the production of illness. Illness experiences of those members of the cult described here appeared to be direct responses to extreme intrapsychic and social control: that is, members were required to be celibate, unmarried, and detached from their pre-cult identity and the emotional support structure of family and friends. Additionally, members were subjected to constant surveillance by peers and were often punished for expressing views that were in conflict with the ideology of the leader, thereby encouraging the somatization of distress. This research is based upon two years of participant observation within the milieu, during which time more than 100 participants were interviewed; however, this paper specifically discusses in-depth interviews with eight individuals whose health problems exemplify those experienced by other members of the cult. PMID:7924401

  14. Somatic mutations activating STAT3 in human inflammatory hepatocellular adenomas

    PubMed Central

    Pilati, Camilla; Amessou, Mohamed; Bihl, Michel P.; Balabaud, Charles; Van Nhieu, Jeanne Tran; Paradis, Valérie; Nault, Jean Charles; Izard, Tina; Bioulac-Sage, Paulette; Couchy, Gabrielle; Poussin, Karine

    2011-01-01

    Inflammatory hepatocellular adenomas (IHCAs) are benign liver tumors. 60% of these tumors have IL-6 signal transducer (IL6ST; gp130) mutations that activate interleukin 6 (IL-6) signaling. Here, we report that 12% of IHCA subsets lacking IL6ST mutations harbor somatic signal transducer and activator of transcription 3 (STAT3) mutations (6/49). Most of these mutations are amino acid substitutions in the SH2 domain that directs STAT3 dimerization. In contrast to wild-type STAT3, IHCA STAT3 mutants constitutively activated the IL-6 signaling pathway independent of ligand in hepatocellular cells. Indeed, the IHCA STAT3 Y640 mutant homodimerized independent of IL-6 and was hypersensitive to IL-6 stimulation. This was associated with phosphorylation of tyrosine 705, a residue required for IL-6–induced STAT3 activation. Silencing or inhibiting the tyrosine kinases JAK1 or Src, which phosphorylate STAT3, impaired constitutive activity of IHCA STAT3 mutants in hepatocellular cells. Thus, we identified for the first time somatic STAT3 mutations in human tumors, revealing a new mechanism of recurrent STAT3 activation and underscoring the role of the IL-6–STAT3 pathway in benign hepatocellular tumorigenesis. PMID:21690253

  15. Interspecies Somatic Cell Nuclear Transfer: Advancements and Problems

    PubMed Central

    Lagutina, Irina; Fulka, Helena; Lazzari, Giovanna

    2013-01-01

    Abstract Embryologists working with livestock species were the pioneers in the field of reprogramming by somatic cell nuclear transfer (SCNT). Without the “Dolly experiment,” the field of cellular reprogramming would have been slow and induced plutipotent cells (iPSCs) would not have been conceived. The major drive of the work in mammalian cloning was the interest of the breeding industry to propagate superior genotypes. Soon it was realized that the properties of oocytes could be used also to clone endangered mammalian species or to reprogram the genomes of unrelated species through what is known as interspecies (i) SCNT, using easily available oocytes of livestock species. iSCNT for cloning animals works only for species that can interbreed, and experiments with taxonomically distant species have not been successful in obtaining live births or deriving embryonic stem cell (ESC) lines to be used for regenerative medicine. There are controversial reports in the literature, but in most cases these experiments have underlined some of the cellular and molecular mechanisms that are incomplete during cell nucleus reprogramming, including the failure to organize nucleoli, silence somatic cell genes, activate the embryonic genome, and resume mitochondrial replication and function, thus indicating nucleus–cytoplasmic incompatibility. PMID:24033141

  16. Infection and inflammation in somatic maintenance, growth and longevity

    PubMed Central

    Kopp, Elizabeth B; Medzhitov, Ruslan

    2009-01-01

    All organisms must display a certain degree of environmental adaptability to survive and reproduce. Growth and reproduction are metabolically expensive and carry other costs that contribute to aging. Therefore, animals have developed physiologic strategies to assess the harshness of the environment before devoting resources to reproduction. Presumably, these strategies maximize the possibility for offspring survival. Current views of aging reflect a trade-off between reproductive fitness and somatic maintenance whereby environmental stress induces an adaptive metabolic response aimed at preserving cellular integrity while inhibiting growth, whereas favorable environmental conditions (abundance of food and water, and optimal temperature, etc.) promote growth and reproductive maturity but simultaneously increase cellular damage and aging. Here we propose that the prevalence of infectious pathogens in a given niche represents an additional environmental factor that, via innate immune pathways, actively shifts this balance in favor of somatic maintenance at the expense of reproduction and growth. We additionally propose the construction of a genetic model system with which to test this hypothesis. PMID:25567853

  17. Mutations to Ku Reveal Differences in Human Somatic Cell Lines

    PubMed Central

    Fattah, Kazi R.; Ruis, Brian L.; Hendrickson, Eric A.

    2008-01-01

    NHEJ (non-homologous end joining) is the predominant mechanism for repairing DNA double-stranded breaks in human cells. One essential NHEJ factor is the Ku heterodimer, which is composed of Ku70 and Ku86. Here we have generated heterozygous loss-of-function mutations for each of these genes in two different human somatic cell lines, HCT116 and NALM-6 using gene targeting. Previous work had suggested that phenotypic differences might exist between the genes and/or between the cell lines. By providing a side-by-each comparison of the four cell lines, we demonstrate that there are indeed subtle differences between loss-of-function mutations for Ku70 versus Ku86, which is accentuated by whether the mutations were derived in the HCT116 or NALM-6 genetic background. Overall, however, the phenotypes of the four lines are quite similar and they provide a compelling argument for the hypothesis that Ku loss-of-function mutations in human somatic cells result in demonstrable haploinsufficiencies. Collectively, these studies demonstrate the importance of proper biallelic expression of these genes for NHEJ and telomere maintenance and they provide insights into why these genes are uniquely essential for primates. PMID:18387344

  18. Somatic Activating PIK3CA Mutations Cause Venous Malformation.

    PubMed

    Limaye, Nisha; Kangas, Jaakko; Mendola, Antonella; Godfraind, Catherine; Schlögel, Matthieu J; Helaers, Raphael; Eklund, Lauri; Boon, Laurence M; Vikkula, Miikka

    2015-12-01

    Somatic mutations in TEK, the gene encoding endothelial cell tyrosine kinase receptor TIE2, cause more than half of sporadically occurring unifocal venous malformations (VMs). Here, we report that somatic mutations in PIK3CA, the gene encoding the catalytic p110? subunit of PI3K, cause 54% (27 out of 50) of VMs with no detected TEK mutation. The hotspot mutations c.1624G>A, c.1633G>A, and c.3140A>G (p.Glu542Lys, p.Glu545Lys, and p.His1047Arg), frequent in PIK3CA-associated cancers, overgrowth syndromes, and lymphatic malformation (LM), account for >92% of individuals who carry mutations. Like VM-causative mutations in TEK, the PIK3CA mutations cause chronic activation of AKT, dysregulation of certain important angiogenic factors, and abnormal endothelial cell morphology when expressed in human umbilical vein endothelial cells (HUVECs). The p110?-specific inhibitor BYL719 restores all abnormal phenotypes tested, in PIK3CA- as well as TEK-mutant HUVECs, demonstrating that they operate via the same pathogenic pathways. Nevertheless, significant genotype-phenotype correlations in lesion localization and histology are observed between individuals with mutations in PIK3CA versus TEK, pointing to gene-specific effects. PMID:26637981

  19. Deflection of Ihc Stereocilia in Response to Somatic Ohc Electromotility

    NASA Astrophysics Data System (ADS)

    Chiaradia, Caio; Nowotny, Manuela; Gummer, Anthony W.

    2009-02-01

    Nowotny and Gummer [1] have recently shown that for stimulus frequencies less than about 3 kHz, the somatic electromotility of the outer hair cells (OHCs) leads to anti-phasic motion of the reticular lamina (RL) and tectorial membrane (TM) in the region of the inner hair cells (IHCs). This motion is predicted to cause displacement of the fluid inside the subtectorialspace, the radial component of which is believed to deflect the IHC stereocilia. We performed experiments in an in-vitro preparation of the guinea-pig cochlea to measure IHC stereocilia motion in response to intracochlear electrical stimulation. The present results show that 1) stereocilia deflection amplitude is high-pass filtered relative to OHC transversal displacement, attaining on average 6 dB and 2) OHC contraction causes IHC stereociliary deflection in the excitatory direction. In summary, in addition to high-frequency tuned amplification, there exists a second "amplifying" process in the cochlea, operating below about 3 kHz, which positively couples somatic electromotility directly to the IHC stereocilia.

  20. Continuity of Functional-Somatic Symptoms from Late Childhood to Young Adulthood in a Community Sample

    ERIC Educational Resources Information Center

    Steinhausen, Hans-Christoph; Metzke, Christa Winkler

    2007-01-01

    Background: The goal of this study was to assess the course of functional-somatic symptoms from late childhood to young adulthood and the associations of these symptoms with young adult psychopathology. Methods: Data were collected in a large community sample at three different points in time (1994, 1997, and 2001). Functional-somatic symptoms…

  1. Fungal Infection Increases the Rate of Somatic Mutation in Scots Pine (Pinus sylvestris L.).

    PubMed

    Ranade, Sonali Sachin; Ganea, Laura-Stefana; Razzak, Abdur M; García Gil, M R

    2015-01-01

    Somatic mutations are transmitted during mitosis in developing somatic tissue. Somatic cells bearing the mutations can develop into reproductive (germ) cells and the somatic mutations are then passed on to the next generation of plants. Somatic mutations are a source of variation essential to evolve new defense strategies and adapt to the environment. Stem rust disease in Scots pine has a negative effect on wood quality, and thus adversely affects the economy. It is caused by the 2 most destructive fungal species in Scandinavia: Peridermium pini and Cronartium flaccidum. We studied nuclear genome stability in Scots pine under biotic stress (fungus-infected, 22 trees) compared to a control population (plantation, 20 trees). Stability was assessed as accumulation of new somatic mutations in 10 microsatellite loci selected for genotyping. Microsatellites are widely used as molecular markers in population genetics studies of plants, and are particularly used for detection of somatic mutations as their rate of mutation is of a much higher magnitude when compared with other DNA markers. We report double the rate of somatic mutation per locus in the fungus-infected trees (4.8×10(-3) mutations per locus), as compared to the controls (2.0×10(-3) mutations per locus) when individual samples were analyzed at 10 different microsatellite markers. Pearson's chi-squared test indicated a significant effect of the fungal infection which increased the number of mutations in the fungus-infected trees (?(2) = 12.9883, df = 1, P = 0.0003134). PMID:25890976

  2. SOMATIC TRANSFORMATION EFFICIENCIES AND EXPRESSION PATTERNS USING THE JCDNV AND PIGGYBAC TRANSPOSON GENE VECTORS IN INSECTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A somatic transformation gene vector has been developed utilizing the integration of viral sequences into insect cells in vivo. The JcDNV somatic transformation vectors are derivatives of plasmids that include the interrupted genome of the Junonia coenia densovirus. Microinjection of these plasmids ...

  3. The somatic cost of reproduction: what determines reproductive effort in prime-aged fallow bucks?

    E-print Network

    Obbard, Darren

    The somatic cost of reproduction: what determines reproductive effort in prime-aged fallow bucks ABSTRACT The somatic costs of reproduction are important for understanding the relationship between sexual of reproductive effort in ungulates. The terminal investment hypothesis predicts that reproductive effort should

  4. Somatic Cell Counts of Milk from Dairy Herd Improvement Herds during 2006

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2006 were examined to assess the status of national milk quality. Cows with records failing some AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to ...

  5. Consequence of changing standards for somatic cell count on US Dairy Herd Improvement herds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Consequence of noncompliance with European Union (EU) and current US standards for somatic cell count (SCC) as well as SCC standards proposed by the National Milk Producers Federation was examined for US herds. Somatic cell scores (SCS) from 14,854 Dairy Herd Improvement (DHI) herds were analyzed. H...

  6. Shyness as a Risk-Factor for Somatic Complaints among Norwegian Adolescents

    ERIC Educational Resources Information Center

    Henriksen, Roger E.; Murberg, Terje A.

    2009-01-01

    The associations between shyness, school-related stress, social support and somatic complaints, were assessed in a sample of 501 pupils from two secondary schools in Norway. The main finding from this cross-sectional study revealed a positive significant association between shyness and somatic complaints. Findings also showed a significant…

  7. Somatic Cell Counts of Milk from Dairy Herd Improvement Herds during 2007

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2007 were examined to assess the status of national milk quality. Cows with records failing some AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to ...

  8. SOMATIC CELL COUNTS OF MILK FROM DAIRY HERD IMPROVEMENT HERDS DURING 2001

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2001 was examined to assess the status of national milk quality. Cows with records failing AIPL editing procedures were excluded. Somatic cell score (SCS) is reported to AIPL and was converted to somati...

  9. The permissibility of using somatic cell nuclear transfer techniques on nonhuman animals 

    E-print Network

    Gatliff, Jason R

    2000-01-01

    Somatic cell nuclear transfer is the process of cloning that produced Dolly. In order to clone an animal using somatic cell nuclear transfer, a donor cell is collected from an animal that one wants to clone and placed in a culture with a very low...

  10. Patterns of Proliferative Activity in the Colonic Crypt Determine Crypt Stability and Rates of Somatic Evolution

    E-print Network

    of Somatic Evolution Rui Zhao, Franziska Michor* Department of Biostatistics and Computational Biology, Dana-Farber Cancer Institute, and Department of Biostatistics, Harvard School of Public Health, Boston, Massachusetts that the proliferation patterns of cells may determine the stability of crypts as well as the rates of somatic evolution

  11. Integrating Fundamental Principles Underlying Somatic Practices into the Dance Technique Class

    ERIC Educational Resources Information Center

    Brodie, Julie; Lobel, Elin

    2004-01-01

    Integrating somatic practices into the dance technique class by bringing awareness to the bodily processes of breathing, sensing, connecting, and initiating can help students reconnect the mind with the body within the context of the classroom environment. Dance educators do not always have the resources to implement separate somatics courses…

  12. Pervasive Developmental Disorder Behavior in Adolescents with Intellectual Disability and Co-Occurring Somatic Chronic Diseases

    ERIC Educational Resources Information Center

    Oeseburg, B.; Groothoff, J. W.; Dijkstra, G. J.; Reijneveld, S. A.; Jansen, D. E. M. C.

    2010-01-01

    Evidence on the association between somatic chronic diseases in ID-adolescents and the full range of pervasive developmental disorder behavior (PDD behavior) is scarce. The aim of the present study is to assess the association between somatic chronic diseases in ID-adolescents and mild PDD behavior. We obtained data on 1044 ID-adolescents, aged…

  13. Factors leading to the reporting of 'functional' somatic symptoms by general practice attenders.

    PubMed Central

    Mumford, D B; Devereux, T A; Maddy, P J; Johnston, J V

    1991-01-01

    The aim of this study was to examine the prevalence of 'functional' somatic symptoms in general practice and the factors associated with reporting these symptoms. During a one month period, all attenders aged 16 years and over at a general practice near Leeds were screened for functional somatic symptoms using the Bradford somatic inventory. The general practitioner recorded the patients' personal data and diagnostic assessment. Data were analysed from 670 Europid patients who completed the Bradford somatic inventory at their first attendance during the month. Higher mean numbers of functional somatic symptoms were found in patients with psychiatric and functional syndromes than in patients with organic illness or in well patients. The symptom score on the Bradford somatic inventory was significantly related to five factors: current anxious mood, current depressed mood, sex, chronic physical illness in a parent and a history of depressive illness. Using multiple linear regression analysis, all five factors were found to be independent predictors of symptom scores on the Bradford somatic inventory. This study highlights the multifactorial aetiology of functional somatic symptoms reported by general practice attenders. PMID:1807304

  14. Parental Reports of Somatic Symptoms in Preschool Children: Prevalence and Associations in a Spanish Sample.

    ERIC Educational Resources Information Center

    Domenech-Llaberia, Edelmira; Jane, Claustre; Canals, Josepa; Ballespi, Sergi; Esparo, Griselda; Garralda, Elena

    2004-01-01

    Objective: To document prevalence and associations of somatic symptoms in Spanish preschool children. Method: Subjects were 3- to 5-year-olds attending nurseries (8 urban, 30 rural). Parental questionnaires (response rate 77%) were used to inquire about somatic symptoms in the child in the 2 weeks prior to assessment, about preschool absence and…

  15. Use of cow culling to help meet compliance for somatic cell standards

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Stricter somatic cell count (SCC) standards are expected in the United States. This study examines the degree to which a single high test increases the risk of non-compliance, and whether culling strategies can help keep the herd in compliance. Source of data was somatic cell scores (SCS) from 14,34...

  16. Smell, Odor, and Somatic Work: Sense-Making and Sensory Management

    ERIC Educational Resources Information Center

    Waskul, Dennis D.; Vannini, Phillip

    2008-01-01

    Sensation (noun) is emergent in joint acts of sensing (verb). To sense, in other words, is to make sense, and sense making entails what we call "somatic work." We investigate these dynamics in the context of olfaction, highlighting how olfaction intersects with social, cultural, and moral order--thus compelling reflexive forms of somatic work by…

  17. The tissue distribution of murine Abcc6 (Mrp6) during embryogenesis indicates that the presence of Abcc6 in elastic tissues is not required for elastic fiber assembly.

    PubMed

    Beck, Konstanze; Dang, Kaohimanu; Boyd, Charles D

    2005-03-01

    Mutations in the gene coding for the ABC transporter, ABCC6, in humans cause Pseudoxanthoma elasticum, which is characterized by the deposition of aberrant elastic fibers. To investigate whether the presence of ABCC6 in tissues synthesizing elastin is required for elastin deposition and elastic fiber assembly, we have compared the steady-state levels and tissue distribution of Abcc6 and tropoelastin mRNAs during mouse embryogenesis. Whereas tropoelastin mRNA levels rose during embryogenesis and were the highest in neonatal mice, Abcc6 mRNA levels remained constantly low throughout embryogenesis. In some tissues, both Abcc6 and tropoelastin mRNA were detected. However, Abcc6 mRNA and protein were not detected in neonatal aorta and arteries, which produce large amounts of elastin indicating that the presence of Abcc6 in elastic tissues is not required for elastic fiber assembly. PMID:15900406

  18. Production of transgenic dairy goat expressing human ?-lactalbumin by somatic cell nuclear transfer.

    PubMed

    Feng, Xiujing; Cao, Shaoxian; Wang, Huili; Meng, Chunhua; Li, Jingxin; Jiang, Jin; Qian, Yong; Su, Lei; He, Qiang; Zhang, Qingxiao

    2015-02-01

    Production of human ?-lactalbumin (h?-LA) transgenic cloned dairy goats has great potential in improving the nutritional value and perhaps increasing the yield of dairy goat milk. Here, a mammary-specific expression vector 5A, harboring goat ?-lactoglobulin (?LG) promoter, the h?-LA gene, neo(r) and EGFP dual markers, was constructed. Then, it was effectively transfected into goat mammary epithelial cells (GMECs) and the expression of h?-LA was investigated. Both the h?-LA transcript and protein were detected in the transfected GMECs after the induction of hormonal signals. In addition, the 5A vector was introduced into dairy goat fetal fibroblasts (transfection efficiency ?60-70%) to prepare competent transgenic donor cells. A total of 121 transgenic fibroblast clones were isolated by 96-well cell culture plates and screened with nested-PCR amplification and EGFP fluorescence. After being frozen for 8 months, the transgenic cells still showed high viabilities, verifying their ability as donor cells. Dairy goat cloned embryos were produced from these h?-LA transgenic donor cells by somatic cell nuclear transfer (SCNT), and the rates of fusion, cleavage, and the development to blastocyst stages were 81.8, 84.4, and 20.0%, respectively. A total of 726 reconstructed embryos derived from the transgenic cells were transferred to 74 recipients and pregnancy was confirmed at 90 days in 12 goats. Of six female kids born, two carried h?-LA and the h?-LA protein was detected in their milk. This study provides an effective system to prepare SCNT donor cells and transgenic animals for human recombinant proteins. PMID:25139669

  19. Isolation of the human chromosomal band Xq28 within somatic cell hybrids by fragile X site breakage.

    PubMed Central

    Warren, S T; Knight, S J; Peters, J F; Stayton, C L; Consalez, G G; Zhang, F P

    1990-01-01

    The chromosomal fragile-site mapping to Xq27.3 is associated with a frequent form of mental retardation and is prone to breakage after induced deoxyribonucleotide pool perturbation. The human hypoxanthine phosphoribosyltransferase (HPRT) and glucose-6-phosphate dehydrogenase (G6PD) genes flank the fragile X chromosome site and can be used to monitor integrity of the site in human-hamster somatic cell hybrids deficient in the rodent forms of these activities. After induction of the fragile X site, negative selection for HPRT and positive enrichment for G6PD resulted in 31 independent colonies of HPRT-,G6PD+ phenotype. Southern blot analysis demonstrated the loss of all tested markers proximal to the fragile X site with retention of all tested human Xq28 loci in a majority of the hybrids. In situ hybridization with a human-specific probe demonstrated the translocation of a small amount of human DNA to rodent chromosomes in these hybrids, suggesting chromosome breakage at the fragile X site and the subsequent translocation of Xq28. Southern blot hybridization of hybrid-cell DNA, resolved by pulsed-field gel electrophoresis, for human-specific repetitive sequences revealed abundant CpG-islands within Xq28, consistent with its known gene density. The electrophoretic banding patterns of human DNA among the hybrids were remarkably consistent, suggesting that fragile X site breakage is limited to a relatively small region in Xq27-28. These somatic cell hybrids, containing Xq27.3-qter as the sole human DNA, will aid the search for DNA associated with the fragile X site and will augment the high resolution genomic analysis of Xq28, including the identification of candidate genes for genetic-disease loci mapping to this region. Images PMID:2339126

  20. RetroSeq: A Tool To Discover Somatic Insertion of Retrotransposons - Elena Helman, TCGA Scientific Symposium 2011

    Cancer.gov

    Home News and Events Multimedia Library Videos RetroSeq: A Tool To Discover Somatic Insertion of Retrotransposons - Elena Helman RetroSeq: A Tool To Discover Somatic Insertion of Retrotransposons - Elena Helman, TCGA Scientific Symposium 2011 You

  1. High-Throughput Somatic Variant Impact Phenotyping Using Gene Expression Signatures - Angela Brooks, TCGA Scientific Symposium 2015

    Cancer.gov

    Home News and Events Multimedia Library Videos High-Throughput Somatic Variant Impact Phenotyping Using Gene Expression Signatures - Angela Brooks, High-Throughput Somatic Variant Impact Phenotyping Using Gene Expression Signatures - Angela Brooks,

  2. Somatic Alterations In Clinically Relevant Cancer Genes Among 12 TCGA Tumor Types - Ali Amin-Mansour, TCGA Scientific Symposium 2014

    Cancer.gov

    Home News and Events Multimedia Library Videos Somatic Alterations In Clinically Relevant Cancer Genes Among 12 TCGA Tumor Types - Ali Amin-Mansour Somatic Alterations In Clinically Relevant Cancer Genes Among 12 TCGA Tumor Types - Ali Amin-Mansour,

  3. The ICGC-TCGA DREAM Somatic Mutation Calling Challenge: Initial Results - Paul Boutros, TCGA Scientific Symposium 2014

    Cancer.gov

    Home News and Events Multimedia Library Videos The ICGC-TCGA DREAM Somatic Mutation Calling Challenge: Initial Results - Paul Boutros The ICGC-TCGA DREAM Somatic Mutation Calling Challenge: Initial Results - Paul Boutros, TCGA Scientific Symposium

  4. Pathway and Network Analysis of Somatic Mutations Across Cancer Types in TCGA - Ben Rafael, TCGA Scientific Symposium 2012

    Cancer.gov

    Home News and Events Multimedia Library Videos Pathway and Network Analysis of Somatic Mutations Across Cancer Types in TCGA - Ben Rafael Pathway and Network Analysis of Somatic Mutations Across Cancer Types in TCGA - Ben Rafael, TCGA Scientific

  5. Chromosome microduplication in somatic cells decreases the genetic stability of human reprogrammed somatic cells and results in pluripotent stem cells

    PubMed Central

    Yu, Yang; Chang, Liang; Zhao, Hongcui; Li, Rong; Fan, Yong; Qiao, Jie

    2015-01-01

    Human pluripotent stem cells, including cloned embryonic and induced pluripotent stem cells, offer a limitless cellular source for regenerative medicine. However, their derivation efficiency is limited, and a large proportion of cells are arrested during reprogramming. In the current study, we explored chromosome microdeletion/duplication in arrested and established reprogrammed cells. Our results show that aneuploidy induced by somatic cell nuclear transfer technology is a key factor in the developmental failure of cloned human embryos and primary colonies from implanted cloned blastocysts and that expression patterns of apoptosis-related genes are dynamically altered. Overall, ~20%–53% of arrested primary colonies in induced plurpotent stem cells displayed aneuploidy, and upregulation of P53 and Bax occurred in all arrested primary colonies. Interestingly, when somatic cells with pre-existing chromosomal mutations were used as donor cells, no cloned blastocysts were obtained, and additional chromosomal mutations were detected in the resulting iPS cells following long-term culture, which was not observed in the two iPS cell lines with normal karyotypes. In conclusion, aneuploidy induced by the reprogramming process restricts the derivation of pluripotent stem cells, and, more importantly, pre-existing chromosomal mutations enhance the risk of genome instability, which limits the clinical utility of these cells. PMID:25965553

  6. Chromosome microduplication in somatic cells decreases the genetic stability of human reprogrammed somatic cells and results in pluripotent stem cells.

    PubMed

    Yu, Yang; Chang, Liang; Zhao, Hongcui; Li, Rong; Fan, Yong; Qiao, Jie

    2015-01-01

    Human pluripotent stem cells, including cloned embryonic and induced pluripotent stem cells, offer a limitless cellular source for regenerative medicine. However, their derivation efficiency is limited, and a large proportion of cells are arrested during reprogramming. In the current study, we explored chromosome microdeletion/duplication in arrested and established reprogrammed cells. Our results show that aneuploidy induced by somatic cell nuclear transfer technology is a key factor in the developmental failure of cloned human embryos and primary colonies from implanted cloned blastocysts and that expression patterns of apoptosis-related genes are dynamically altered. Overall, ~20%-53% of arrested primary colonies in induced plurpotent stem cells displayed aneuploidy, and upregulation of P53 and Bax occurred in all arrested primary colonies. Interestingly, when somatic cells with pre-existing chromosomal mutations were used as donor cells, no cloned blastocysts were obtained, and additional chromosomal mutations were detected in the resulting iPS cells following long-term culture, which was not observed in the two iPS cell lines with normal karyotypes. In conclusion, aneuploidy induced by the reprogramming process restricts the derivation of pluripotent stem cells, and, more importantly, pre-existing chromosomal mutations enhance the risk of genome instability, which limits the clinical utility of these cells. PMID:25965553

  7. Low inductance gas switching.

    SciTech Connect

    Chavez, Ray; Harjes, Henry Charles III; Wallace, Zachariah; Elizondo, Juan E.

    2007-10-01

    The laser trigger switch (LTS) is a key component in ZR-type pulsed power systems. In ZR, the pulse rise time through the LTS is > 200 ns and additional stages of pulse compression are required to achieve the desired <100 ns rise time. The inductance of the LTS ({approx}500nH) in large part determines the energy transfer time through the switch and there is much to be gained in improving system performance and reducing system costs by reducing this inductance. The current path through the cascade section of the ZR LTS is at a diameter of {approx} 6-inches which is certainly not optimal from an inductance point of view. The LTS connects components of much greater diameter (typically 4-5 feet). In this LDRD the viability of switch concepts in which the diameter of cascade section is greatly increased have been investigated. The key technical question to be answered was, will the desired multi-channel behavior be maintained in a cascade section of larger diameter. This LDRD proceeded in 2 distinct phases. The original plan for the LDRD was to develop a promising switch concept and then design, build, and test a moderate scale switch which would demonstrate the key features of the concept. In phase I, a switch concept which meet all electrical design criteria and had a calculated inductance of 150 nH was developed. A 1.5 MV test switch was designed and fabrication was initiated. The LDRD was then redirected due to budgetary concerns. The fabrication of the switch was halted and the focus of the LDRD was shifted to small scale experiments designed to answer the key technical question concerning multi-channel behavior. In phase II, the Multi-channel switch test bed (MCST) was designed and constructed. The purpose of MCST was to provide a versatile, fast turn around facility for the study the multi-channel electrical breakdown behavior of a ZR type cascade switch gap in a parameter space near that of a ZR LTS. Parameter scans on source impedance, gap tilt, gap spacing and electrode diameter were conducted.

  8. Aryl organophosphate flame retardants induced cardiotoxicity during zebrafish embryogenesis: by disturbing expression of the transcriptional regulators.

    PubMed

    Du, Zhongkun; Wang, Guowei; Gao, Shixiang; Wang, Zunyao

    2015-04-01

    As a result of the ban on some brominated flame retardants (BFRs), the use of organophosphate flame retardants (OPFRs) increases, and they are detected in multi-environment media at higher frequency and concentrations. However, the toxicity data of OPFRs, especially those on developmental toxicology are quite limited, which prevents an accurate evaluation of their environmental and health risk. Because a previous study reported that two aryl-OPFRs induced cardiotoxicity during zebrafish embryogenesis, we designed experiments to compare the heart developmental toxicity of a series of aryl-OPFRs with alkyl-OPFRs and explored possible internal mechanism. First, acute toxicity of 9 frequently used OPFRs were studied with zebrafish embryos (2-96 hpf). By comparing the LC50 and EC50 (pericardium edema) data, two aryl-OPFRs, triphenyl phosphate (TPhP) and cresyl diphenyl phosphate (CDP) showed greater heart developmental toxicity than the others. It was also found that the acute toxicity of OPFRs varied mainly depending on their hydrophobicity. Further study on the cardiotoxicity of TPhP and CDP showed that the cardiac looping progress can be impeded by 0.10mg/L TPhP or CDP exposure. Bradycardia and reduction of myocardium were also observed in 0.50 and 1.0mg/L TPhP groups and 0.10, 0.50, and 1.0mg/L CDP groups. 0-48 hpf is the vulnerable window of zebrafish cardiogenesis that can be easily affected by TPhP and CDP. RT-qPCR measurement on the expressions of key transcriptional regulators in cardiogenesis showed that BMP4, NKX2-5, and TBX5 were significantly inhibited at the exposure points of 12 hpf and 24 hpf which may be the internal factors related to the heart developmental toxicity. As zebrafish is a good model organism for human health study, the present results call for a greater attention to the health risk of fetus in pregnant women exposed to such OPFRs. PMID:25661707

  9. Macondo crude oil from the Deepwater Horizon oil spill disrupts specific developmental processes during zebrafish embryogenesis

    PubMed Central

    2012-01-01

    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 hydrocarbon components of the oil. Conclusions Whether these teratogenic effects are unique to the oil from the Deepwater Horizon oil spill or generalizable for most crude oil types remains to be determined. This work establishes a model for further investigation into the molecular mechanisms behind crude oil mediated deformations. In addition, due to the high conservation of genetic and cellular processes between zebrafish and other vertebrates, our work also provides a platform for more focused assessment of the impact that the Deepwater Horizon oil spill has had on the early life stages of native fish species in the Gulf of Mexico and the Atlantic Ocean. PMID:22559716

  10. Effects of doxycycline on heartworm embryogenesis, transmission, circulating microfilaria, and adult worms in microfilaremic dogs.

    PubMed

    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 were ever positive for microfilariae or antigen, and none had worms at necropsy; three control dogs were positive for microfilariae and antigen and had many live worms. These data indicate that doxycycline treatment of microfilaremic dogs gradually reduces numbers of microfilariae and blocks further transmission of heartworms. This latter effect should be highly effective in reducing the rate of selection of heartworms with genes that confer resistance to macrocyclic lactone preventives and microfilaricides. The data also suggest that doxycycline has a slow-kill effect on adult heartworms. PMID:25458121

  11. Identification of QTLs Associated with Callogenesis and Embryogenesis in Oil Palm Using Genetic Linkage Maps Improved with SSR Markers

    PubMed Central

    Ting, Ngoot-Chin; Jansen, Johannes; Nagappan, Jayanthi; Ishak, Zamzuri; Chin, Cheuk-Weng; Tan, Soon-Guan; Cheah, Suan-Choo; Singh, Rajinder

    2013-01-01

    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. PMID:23382832

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

    PubMed Central

    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. PMID:26682887

  13. G-protein-coupled estrogen receptor 1 is involved in brain development during zebrafish (Danio rerio) embryogenesis

    SciTech Connect

    Shi, Yanan; Liu, Xiaochun; Zhu, Pei; Li, Jianzhen; Sham, Kathy W.Y.; Cheng, Shuk Han; Li, Shuisheng; Zhang, Yong; Cheng, Christopher H.K.; Lin, Haoran; College of Ocean, Hainan University, Haikou 570228, Hainan

    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.

  14. Overexpression and mechanistic characterization of blastula protease 10, a metalloprotease involved in sea urchin embryogenesis and development.

    PubMed

    da Silva, Giordano F Z; Reuille, Rae L; Ming, Li-June; Livingston, Brian T

    2006-04-21

    Blastula protease 10 (BP10) is a metalloenzyme involved in sea urchin embryogenesis, which has been assigned to the astacin family of zinc-dependent endopeptidases. It shows greatest homology with the mammalian tolloid-like genes and contains conserved structural motifs consistent with astacin, tolloid, and bone morphogenetic protein 1. Astacin, a crustacean digestive enzyme, has been proposed to carry out hydrolysis via a metal-centered mechanism that involves a metal-coordinated "tyrosine switch." It has not been determined if the more structurally complex members of this family involved in eukaryotic development share this mechanism. The recombinant BP10 has been overexpressed in Escherichia coli, its metalloenzyme nature has been confirmed, and its catalytic properties have been characterized through kinetic studies. BP10 shows significant hydrolysis toward gelatin both in its native zinc-containing form and copper derivative. The copper derivative of BP10 shows a remarkable 960% rate acceleration toward the hydrolysis of the synthetic substrate N-benzoyl-arginine-p-nitroanilide when compared with the zinc form. The enzyme also shows calcium-dependent activation. These are the first thorough mechanistic studies reported on BP10 as a representative of the more structurally complex members of astacin-type enzymes in deuterostomes, which can add supporting data to corroborate the metal-centered mechanism proposed for astacin and the role of the coordinated Tyr. We have demonstrated the first mechanistic study of a tolloid-related metalloenzyme involved in sea urchin embryogenesis. PMID:16492671

  15. A change of developmental program induces the remodeling of the interchromatin domain during microspore embryogenesis in Brassica napus L.

    PubMed

    Seguí-Simarro, J M; Corral-Martínez, P; Corredor, E; Raska, I; Testillano, P S; Risueño, M C

    2011-05-15

    After a stress treatment, in vitro-cultured pollen changes its normal gametophytic developmental pathway towards embryogenesis producing multicellular embryos from which, finally, haploid and double haploid plants develop. The architecture of the well-organized nuclear functional domains changes in response to DNA replication, RNA transcription, processing and transport dynamics. A number of subnuclear structures present in the interchromatin region (IR, the nuclear domain between chromosome territories) have been shown as involved, either directly or indirectly, in transcriptional regulation. These structures include the interchromatin granule clusters (IGCs), perichromatin fibrils (PFs), Cajal bodies (CBs) and perichromatin granules (PGs). In this work, we present a cytochemical, immunocytochemical, quantitative and morphometric analysis at the light, confocal and electron microscopy levels to characterize the changes in the functional architecture of the nuclear interchromatin domain during two developmental programs followed by the microspore: differentiation to mature pollen grains (transcriptionally inactive), and microspore embryogenesis involving proliferation in the first stages (highly engaged in transcription). Our results revealed characteristic changes in size, shape and distribution of the different interchromatin structures as a consequence of the reprogramming of the microspore, allowing us to relate the remodeling of the interchromatin domain to the variations in transcriptional activities during proliferation and differentiation events, and suggesting that RNA-associated structures could be a regulatory mechanism in the process. In addition, we document the presence of two structurally different types of CBs, and of IGC and CB-associated regions, similar to those present in animal cells, and not yet described in plants. PMID:21216028

  16. Induction of autophagy improves embryo viability in cloned mouse embryos.

    PubMed

    Shen, XingHui; Zhang, Na; Wang, ZhenDong; Bai, GuangYu; Zheng, Zhong; Gu, YanLi; Wu, YanShuang; Liu, Hui; Zhou, DongJie; Lei, Lei

    2015-01-01

    Autophagy is an essential cellular mechanism that degrades cytoplasmic proteins and organelles to recycle their components. Moreover, autophagy is essential for preimplantation development in mammals. Here we show that autophagy is also important for reprogramming in somatic cell nuclear transfer (SCNT). Our data indicate that unlike fertilized oocytes, autophagy is not triggered in SCNT embryos during 6?hours of activation. Mechanistically, the inhibited autophagic induction during SCNT activation is due to the cytochalasin B (CB) caused depolymerization of actin filaments. In this study, we induced autophagy during SCNT activation by rapamycin and pp242, which could restore the expected level of autophagy and significantly enhance the development of SCNT embryos to the blastocyst stage when compared with the control (68.5% and 68.7% vs. 41.5%, P?induction during SCNT activation might be one of the serious causes of low efficiency of SCNT. PMID:26643778

  17. Induction of autophagy improves embryo viability in cloned mouse embryos

    PubMed Central

    Shen, XingHui; Zhang, Na; Wang, ZhenDong; Bai, GuangYu; Zheng, Zhong; Gu, YanLi; Wu, YanShuang; Liu, Hui; Zhou, DongJie; Lei, Lei

    2015-01-01

    Autophagy is an essential cellular mechanism that degrades cytoplasmic proteins and organelles to recycle their components. Moreover, autophagy is essential for preimplantation development in mammals. Here we show that autophagy is also important for reprogramming in somatic cell nuclear transfer (SCNT). Our data indicate that unlike fertilized oocytes, autophagy is not triggered in SCNT embryos during 6?hours of activation. Mechanistically, the inhibited autophagic induction during SCNT activation is due to the cytochalasin B (CB) caused depolymerization of actin filaments. In this study, we induced autophagy during SCNT activation by rapamycin and pp242, which could restore the expected level of autophagy and significantly enhance the development of SCNT embryos to the blastocyst stage when compared with the control (68.5% and 68.7% vs. 41.5%, P?induction during SCNT activation might be one of the serious causes of low efficiency of SCNT. PMID:26643778

  18. Teaching engineering ethics by conceptual design: the somatic marker hypothesis.

    PubMed

    Kallenberg, Brad J

    2009-12-01

    In 1998, a lead researcher at a Midwestern university submitted as his own a document that had 64 instances of strings of 10 or more words that were identical to a consultant's masters thesis and replicated a data chart, all of whose 16 entries were identical to three and four significant figures. He was fired because his actions were wrong. Curiously, he was completely unable to see that his actions were wrong. This phenomenon is discussed in light of recent advances in neuroscience and used to argue for a change in the standard way engineering ethics is taught. I argue that engineering ethics is better taught in the form of a design course in order to maximize "somatic" learning. PMID:19360482

  19. Sterile mutants of Schizosaccharomyces pombe: Analysis by somatic hybridization.

    PubMed

    Girgsdies, O

    1982-12-01

    Sixteen sterile mutants of Schizosaccharomyces pombe, isolated from homothallic h (90)strains, were examined. It was found that they are blocked either in copulation and meiosis or in copulation alone.Protoplasts of the sterile strains were fused with protoplasts of h(+N), h(-S) or h (90)strains. In these somatic crosses, eight of the sterile strains yielded hybrids which were able to form azygotic asci. Tetrad analyses revealed that seven of these sterile strains contain a single mutation; the mutations represent at least five sterility genes (ste2, ste3, ste4, ste5, ste6). One sterile strain contains two unlinked mutations which do not represent sterility genes, but genes the interaction of which results in a sterile phenotype. PMID:24186549

  20. Somatically segregating clone of apomictic maize-tripsacum hybrid

    SciTech Connect

    Yudin, B.F.; Lukina, L.A.

    1988-11-01

    The results of further study on clone AM-5, isolated in the progeny of /gamma/-irradiated plants of the apomictic hybrid of maize with tripsacum (2n = 38) are reported. The variegated-leaf seedlings of the clone segregate somatically and produce variegated, mottled, green (phenotypically normal) plants in different ratios in the apomictic progenies. The variegated, and to a lesser degree, green segregants segregate further. The mottled apomictics as well as mottled branches of variegated seedlings maintain their phenotype on transplantation, however, these is a progressive enhancement of the characters of vegetative lethality. Lethals of two extra maize genomes to the AM-5 nucleus does not affect significantly the scope and nature of segregation. At the same time, the loss of tripsacum genome restores normal phenotype. Clone AM-5 is an example of hybrid apomictic form causing significant morphological variability, which is, nevertheless, not related with apomictic and reversion to the sexual process.