Science.gov

Sample records for somatic embryogenesis induction

  1. Induction of direct somatic embryogenesis in garlic (Allium sativum).

    PubMed

    Sata, S J; Bagatharia, S B; Thaker, V S

    2000-01-01

    An efficient novel method of direct somatic embryogenesis from basal tissue of garlic clove was developed. The influence of plant growth regulators, basal medium and explant type on somatic embryo induction was examined. The best plant growth regulator combination was, 2,4-D and kinetin at 1.0 mg/L and 0.5 mg/L respectively, inducing direct somatic embryogenesis in 60% of explants. White's medium was used as basal medium and somatic embryos developed on explants after six weeks. The technique has potential applicability for problems associated with plant regeneration and virus elimination in garlic. PMID:11549942

  2. Induction of somatic embryogenesis in gum arabic tree [Acacia senegal (L.) Willd].

    PubMed

    Rathore, Jitendra Singh; Rai, Manoj K; Shekhawat, N S

    2012-10-01

    Factors affecting somatic embryogenesis from immature cotyledon of gum arabic tree [Acacia senegal (L.) Willd.] were investigated. Induction of somatic embryogenesis was influenced by plant growth regulator concentrations and addition of amino acids in medium. Best induction of somatic embryogenesis was obtained on MS medium supplemented with 0.45 μM 2, 4-D, 2.32 μM Kin and 15 mM L-glutamine. L-glutamine plays a significant role in the maturation of somatic embryos and most of embryos attained maturity only on L-glutamine (15 mM) containing medium. Maximum percent (75.0 ± 2.5) germination of somatic embryos was recorded on medium containing 0.22 μM BAP. PMID:24082503

  3. Possible involvement of abscisic acid in the induction of secondary somatic embryogenesis on seed-coat-derived carrot somatic embryos.

    PubMed

    Ogata, Yumiko; Iizuka, Misato; Nakayama, Daisuke; Ikeda, Miho; Kamada, Hiroshi; Koshiba, Tomokazu

    2005-06-01

    When seed coats (pericarps) were picked from 14-day-old carrot (Daucus carota) seedlings and cultured on agar plates, embryogenic cell clusters were produced very rapidly at a high frequency on the open side edge. Embryo induction progressed without auxin treatment; indeed treatment caused the formation of non-embryogenic callus. The embryogenic tissues (primary embryos) developed normally until the torpedo stage; however, after this a number of secondary somatic embryos were produced in the hypocotyl and root regions. "Tertiary" embryos were formed on some of the secondary embryos, but many developed into normal plantlets. The primary embryos contained significantly higher levels of abscisic acid (ABA) than the hypocotyl-derived normal and seed-coat-derived secondary embryos. Fluridone inhibited the induction of secondary embryogenesis, while exogenously supplied ABA induced not only "tertiary" embryogenesis on the seed-coat-derived secondary embryos, but also secondary embryos on the hypocotyl-derived normal somatic embryos. These results indicate that ABA is one of the important endogenous factors for the induction of secondary embryogenesis on carrot somatic embryos. Higher levels of indole-3-acetic acid (IAA) in primary embryos also suggest the presence of some concerted effect of ABA and IAA on the induction of secondary embryogenesis in primary embryos. PMID:15770487

  4. Protocol for Callus Induction and Somatic Embryogenesis in Moso Bamboo

    PubMed Central

    Wu, Xiao-Li; Gu, Xiao-Ping

    2013-01-01

    Moso bamboo [Phyllostachys heterocycla var. pubescens (Mazel ex J. Houz.) Ohwi] is one of the most important forest crops in China and the rest of Asia. Although many sympodial bamboo tissue culture protocols have been established, there is no protocol available for plantlet regeneration as indicated by callus induction for monopodial bamboos, such as Moso bamboo. In the present report, embryogenic callus induction, embryoid development, and germination were established for Moso bamboo from zygotic seed embryos. Callus was initiated from zygotic embryos after 10–20 d culture on MS media supplemented with 4.0 mg/L 2, 4-D and 0.1 mg/L zeatin (ZT). About 50% of the explants produced calli, and nearly 15% of the calli were found to be embryogenic in nature. These embryogenic calli can be subcultured for proliferation in the Murashige and Skoog media (MS) supplemented with 0.5–2.0 mg/L 2, 4-D. These calli were found to have maintained their capacity for regeneration even after one year of subculture. The viable somatic embryoids regenerated in medium containing 5.0–7.0 mg/L ZT. Nearly 5% of the calli were found capable of regenerating into plantlets directly in MS medium containing 5.0–7.0 mg/L ZT. Root growth was more pronounced when the plantlets were transferred to medium containing 2.0 mg/L NAA. After 30 days of subculture, the plantlets were transferred to a greenhouse. PMID:24349159

  5. 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

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

    PubMed Central

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

    2013-01-01

    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

  7. Application of Somatic Embryogenesis in Woody Plants.

    PubMed Central

    Guan, Yuan; Li, Shui-Gen; Fan, Xiao-Fen; Su, Zhen-Hong

    2016-01-01

    Somatic embryogenesis is a developmental process where a plant somatic cell can dedifferentiate to a totipotent embryonic stem cell that has the ability to give rise to an embryo under appropriate conditions. This new embryo can further develop into a whole plant. In woody plants, somatic embryogenesis plays a critical role in clonal propagation and is a powerful tool for synthetic seed production, germplasm conservation, and cryopreservation. A key step in somatic embryogenesis is the transition of cell fate from a somatic cell to embryo cell. Although somatic embryogenesis has already been widely used in a number of woody species, propagating adult woody plants remains difficult. In this review, we focus on molecular mechanisms of somatic embryogenesis and its practical applications in economic woody plants. Furthermore, we propose a strategy to improve the process of somatic embryogenesis using molecular means. PMID:27446166

  8. 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

  9. 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

  10. Somatic embryogenesis - Stress-induced remodeling of plant cell fate.

    PubMed

    Fehér, Attila

    2015-04-01

    Plants as sessile organisms have remarkable developmental plasticity ensuring heir continuous adaptation to the environment. An extreme example is somatic embryogenesis, the initiation of autonomous embryo development in somatic cells in response to exogenous and/or endogenous signals. In this review I briefly overview the various pathways that can lead to embryo development in plants in addition to the fertilization of the egg cell and highlight the importance of the interaction of stress- and hormone-regulated pathways during the induction of somatic embryogenesis. Somatic embryogenesis can be initiated in planta or in vitro, directly or indirectly, and the requirement for dedifferentiation as well as the way to achieve developmental totipotency in the various systems is discussed in light of our present knowledge. The initiation of all forms of the stress/hormone-induced in vitro as well as the genetically provoked in planta somatic embryogenesis requires extensive and coordinated genetic reprogramming that has to take place at the chromatin level, as the embryogenic program is under strong epigenetic repression in vegetative plant cells. Our present knowledge on chromatin-based mechanisms potentially involved in the somatic-to-embryogenic developmental transition is summarized emphasizing the potential role of the chromatin to integrate stress, hormonal, and developmental pathways leading to the activation of the embryogenic program. The role of stress-related chromatin reorganization in the genetic instability of in vitro cultures is also discussed. This article is part of a Special Issue entitled: Stress as a fundamental theme in cell plasticity. PMID:25038583

  11. 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

  12. 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

  13. 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...

  14. Somatic Embryogenesis in Peach Palm Using the Thin Cell Layer Technique: Induction, Morpho-histological Aspects and AFLP Analysis of Somaclonal Variation

    PubMed Central

    Steinmacher, D. A.; Krohn, N. G.; Dantas, A. C. M.; Stefenon, V. M.; Clement, C. R.; Guerra, M. P.

    2007-01-01

    Background and Aims The thin cell layer (TCL) technique is based on the use of very small explants and has allowed enhanced in vitro morphogenesis in several plant species. The present study evaluated the TCL technique as a procedure for somatic embryo production and plantlet regeneration of peach palm. Methods TCL explants from different positions in the shoot apex and leaf sheath of peach palm were cultivated in MS culture medium supplemented with 0–600 µm Picloram in the presence of activated charcoal. The production of primary calli and embryogenic calli was evaluated in these different conditions. Histological and amplified fragment length polymorphism (AFLP) analyses were conducted to study in vitro morphogenetic responses and genetic stability, respectively, of the regenerated plantlets. Key Results Abundant primary callus induction was observed from TCLs of the shoot meristem in culture media supplemented with 150–600 µm Picloram (83–97 %, respectively). The production of embryogenic calli depends on Picloram concentration and explant position. The best response observed was 43 % embryogenic callus production from shoot meristem TCL on 300 µm Picloram. In maturation conditions, 34 ± 4 somatic embryos per embryogenic callus were obtained, and 45·0 ± 3·4 % of these fully developed somatic embryos were converted, resulting in plantlets ready for acclimatization, of which 80 % survived. Histological studies revealed that the first cellular division events occurred in cells adjacent to vascular tissue, resulting in primary calli, whose growth was ensured by a meristematic zone. A multicellular origin of the resulting somatic embryos arising from the meristematic zone is suggested. During maturation, histological analyses revealed bipolarization of the somatic embryos, as well as the development of new somatic embryos. AFLP analyses revealed that 92 % of the regenerated plantlets were true to type. The use of TCL explants considerably improves the

  15. 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.

  16. 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.

  17. 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

  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. In vitro plant regeneration of Aster scaber via somatic embryogenesis.

    PubMed

    Boo, Kyung Hwan; Cao, Dang Viet; Pamplona, Reniel S; Lee, Doseung; Riu, Key-Zung; Lee, Dong-Sun

    2015-01-01

    We established an in vitro plant regeneration system via somatic embryogenesis of Aster scaber, an important source of various biologically active phytochemicals. We examined the callus induction and embryogenic capacities of three explants, including leaves, petioles, and roots, on 25 different media containing different combinations of α-naphthalene acetic acid (NAA) and 6-benzyladenine (BA). The optimum concentrations of NAA and BA for the production of embryogenic calli were 5.0 μM and 0.05 μM, respectively. Media containing higher concentrations of auxin and cytokinin (such as 25 μM NAA and 25 μM BA) were suitable for shoot regeneration, especially for leaf-derived calli, which are the most readily available calli and are highly competent. For root induction from regenerated shoots, supplemental auxin and/or cytokinin did not improve rooting, but instead caused unwanted callus induction or retarded growth of regenerated plants. Therefore, plant growth regulator-free medium was preferable for root induction. Normal plants were successfully obtained from calli under the optimized conditions described above. This is the first report of the complete process of in vitro plant regeneration of A. scaber via somatic embryogenesis. PMID:25640866

  20. 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

  1. Indirect somatic embryogenesis in cassava for genetic modification purposes.

    PubMed

    Raemakers, Krit; Pereira, Isolde; van Putten, Herma Koehorst; Visser, Richard

    2006-01-01

    In cassava both direct and indirect somatic embryogenesis is described. Direct somatic embryogenesis starts with the culture of leaf explants on Murashige and Skoog (MS) medium supplemented with auxins. Somatic embryos undergo secondary somatic embryogenesis when cultured on the same medium. Indirect somatic embryogenesis is initiated by subculture of directly induced embryogenic tissue on auxin-supplemented medium with Gresshoff and Doy salts and vitamins. A very fine friable embryogenic callus (FEC) is formed after a few rounds of subculture and stringent selection. This FEC is maintained by subculture on auxin supplemented medium. Lowering of the auxin concentration allows the FEC to form mature somatic embryos that develop into plants when transferred to a cytokinin-supplemented medium. PMID:16673909

  2. 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

  3. Relationship between ploidy variation of citrus calli and competence for somatic embryogenesis.

    PubMed

    Zhang, Jun-E; Guo, Wen-Wu; Deng, Xiu-Xin

    2006-07-01

    This study focuses on the relationship between the genetic variation of calli and the competence for somatic embryogenesis in citrus. The DNA content of 35 citrus calli of different genotypes was measured three times by flow cytometry during a period of four years. The results showed that 71.4 % of the genotypes had a progressive increase of varied cells, while those of Page tangelo, Shamouti sweet orange, Russ navel orange and Cleopatra decreased; significant difference in the variation degree (percentages) existed among genotypes. Studies carried out on the induction of somatic embryogenesis revealed that 9 out of the 35 genotypes had still kept the competence of somatic embryogenesis, and the rest 26 had lost the competence. Correlation analysis indicated that there was no significant relationship between the variation degree and the embryogenesis competence r = -0.10 (P < 0.01), neither for the relationship between the subculture duration and the regeneration capacity. PMID:16875323

  4. Somatic Embryogenesis of Abies cephalonica Loud.

    PubMed

    Krajňáková, 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

  5. Somatic embryogenesis in Picea suspension cultures.

    PubMed

    Stasolla, Claudio

    2006-01-01

    Generation of somatic embryos in spruce is achieved through the execution of five steps designated as: (1) induction of embryogenic tissue, (2) maintenance of embryogenic tissue, (3) embryo development, (4) embryo maturation, and (5) conversion into plants. Depending on species and genotypes within the same species, each step must be optimized for obtaining maximum results. In general, embryogenic tissue is generated from immature and mature zygotic embryos and maintained in either liquid or solid conditions in the presence of plant growth regulators auxin and cytokinin. Initiation of embryo development in suspension cultured is induced by removal of plant growth regulators, whereas continuation of development and completion of maturation require applications of abscisic acid and imposition of a desiccation period. Both treatments are needed for conferring morphological and physiological maturation to the embryos. Mature somatic embryos are germinated in the absence of plant regulators and embryo conversion (i.e., formation of a functional shoot and root, occurs after a few weeks in culture). PMID:16673908

  6. Callose deposition is required for somatic embryogenesis in plasmolyzed Eleutherococcus senticosus zygotic embryos.

    PubMed

    Tao, Lei; Yang, Yang; Wang, Qiuyu; You, Xiangling

    2012-01-01

    Dynamic changes in callose content, which is deposited as a plant defense response to physiological changes, were analyzed during somatic embryogenesis in Eleutherococcus senticosus zygotic embryos plasmolyzed in 1.0 M mannitol. During plasmolysis, callose deposition was clearly observed inside the plasma membrane of zygotic embryo epidermal cells using confocal laser scanning microscopy. The callose content of zygotic embryos gradually increased between 0 and 12 h plasmolysis and remained stable after 24 h plasmolysis. During eight weeks induction of somatic embryogenesis, the callose content of explants plasmolyzed for 12 h was slightly higher than explants plasmolyzed for 6 or 24 h, with the largest differences observed after 6 weeks culture, which coincided with the maximum callose content and highest number of globular somatic embryos. The highest frequency of somatic embryo formation was observed in explants plasmolyzed for 12 h. The somatic embryo induction rate and number of somatic embryos per explant were markedly different in zygotic embryos pretreated with plasmolysis alone (78.0%, 43 embryos per explant) and those pretreated with plasmolysis and the callose synthase inhibitor 2-deoxy-d-glucose (11.5%, 8 embryos per explant). This study indicates that callose production is required for somatic embryogenesis in plasmolyzed explants. PMID:23203053

  7. 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 α-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

  8. 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 ...

  9. 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

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

    PubMed

    da Silva, Jaime A Teixeira; Winarto, Budi

    2016-01-01

    The protocorm-like body (PLB) is the de facto somatic embryo in orchids. Here we describe detailed protocols for two orchid genera (hybrid Cymbidium Twilight Moon 'Day Light' and Dendrobium 'Jayakarta', D. 'Gradita 31', and D. 'Zahra FR 62') for generating PLBs. These protocols will most likely have to be tweaked for different cultivars as the response of orchids in vitro tends to be dependent on genotype. In addition to primary somatic embryogenesis, secondary (or repetitive) somatic embryogenesis is also described for both genera. The use of thin cell layers as a sensitive tissue assay is outlined for hybrid Cymbidium while the protocol outlined is suitable for bioreactor culture of D. 'Zahra FR 62'. PMID:26619873

  11. Molecular characterization of a Cyrtochilum loxense Somatic Embryogenesis Receptor-like Kinase (SERK) gene expressed during somatic embryogenesis.

    PubMed

    Cueva, Augusta; Concia, Lorenzo; Cella, Rino

    2012-06-01

    Somatic embryogenesis is crucial for the propagation of endangered Ecuadorian orchid species, among them Cyrtochilum loxense, in view of the fact that their number in nature or in collections is quite reduced. One of the genes expressed during somatic and zygotic embryogenesis is Somatic Embryogenesis Receptor-like Kinase (SERK). Despite the development of somatic embryogenesis protocols for orchids, no SERK genes have been isolated from this family. This is the first report on the isolation of a full-length orchid SERK sequence, namely that of Cyrtochilum loxense (ClSERK). The identity of ClSERK was inferred by the presence of all domains typical of SERK proteins: a signal peptide, a leucine zipper domain, five LRRs, a serine proline-rich domain, a transmembrane domain, a kinase domain, and the C-terminal region. We have observed that the ClSERK gene is highly expressed in embryogenic calluses generated from protocorms at the time of appearance of embryonic morphological features. At later stages when embryos become well visible on calluses, ClSERK gene expression decreases. Compared to early stages of embryo formation on calluses, the expression detected in leaf tissue is far lower, thus suggesting a role of this gene during development. PMID:22350407

  12. Somatic embryogenesis and plant regeneration in Carica papaya L. tissue culture derived from root explants.

    PubMed

    Chen, M H; Wang, P J; Maeda, E

    1987-10-01

    The regeneration potential of shoot tip, stem, leaf, cotyledon and root explants of two papaya cultivars (Carica papaya cv. 'Solo' and cv. 'Sunrise') were studed. Callus induction of these two cultivars of papaya showed that the shoot tips and stems are most suitable for forming callus, while leaves, cotyledons and roots are comparatively difficult to induce callus. Callus induction also varied with the varities. Somatic embryogenesis was obtained from 3-month-old root cultures. A medium containing half strength of MS inorganic salts, 160 mg/l adenine sulfate, 1.0 mg/1 NAA, 0.5 mg/1 kinetin and 1.0 mg/1 GA3 was optimal for embryogenesis. The callus maintained high regenerative capacity after two years of culture on this medium. Plants derived from somatic embryos were obtained under green-house conditions. PMID:24248842

  13. Role of trace elements in somatic embryogenesis A PIXE study

    NASA Astrophysics Data System (ADS)

    Saha, P.; Raychaudhuri, S.; Mishra, D.; Chakraborty, A.; Sudarshan, M.

    2008-03-01

    Proton induced X-ray emission was used to study the trace elemental profiles of embryogenic and non-embryogenic callus of an important cash crop of India - Plantago ovata. Somatic embryogenesis, a well-known process for plant regeneration and crop improvement is modulated by various factors such as ionizing radiation and micro nutrients in the growth media. The present work reports the trace element variation in normal and irradiated callus tissue of P. ovata. Embryogenic and non-embryogenic callus tissues were exposed to gamma rays from a 60Co gamma source. The absorbed dose ranged from 10 to 100 Gy. Subsequent experiments showed significant dose dependent alterations in K, Ca, Mn, Fe, Ni, Cu, Zn, Br, Sr in both the embryogenic and non-embryogenic callus. The precise involvement of these elements has been discussed in light of somatic embryogenesis of the selected medicinal plant.

  14. Alternative oxidase involvement in Daucus carota somatic embryogenesis.

    PubMed

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

    2009-12-01

    Plant alternative oxidase (AOX) is a mitochondrial inner membrane enzyme involved in alternative respiration. The critical importance of the enzyme during acclimation upon stress of plant cells is not fully understood and is still an issue of intensive research and discussion. Recently, a role of AOX was suggested for the ability of plant cells to change easily its fate upon stress. In order to get new insights about AOX involvement in cell reprogramming, quantitative real-time polymerase chain reaction (PCR) and inhibitor studies were performed during cell redifferentiation and developmental stages of Daucus carota L. somatic embryogenesis. Transcript level analysis shows that D. carota AOX genes (DcAOX1a and DcAOX2a) are differentially expressed during somatic embryogenesis. DcAOX1a shows lower expression levels, being mainly down-regulated, whereas DcAOX2a presented a large up-regulation during initiation of the realization phase of somatic embryogenesis. However, when globular embryos start to develop, both genes are down-regulated, being this state transient for DcAOX2a. In addition, parallel studies were performed using salicylhydroxamic acid (SHAM) in order to inhibit AOX activity during the realization phase of somatic embryogenesis. Embryogenic cells growing in the presence of the inhibitor were unable to develop embryogenic structures and its growth rate was diminished. This effect was reversible and concentration dependent. The results obtained contribute to the hypothesis that AOX activity supports metabolic reorganization as an essential part of cell reprogramming and, thus, enables restructuring and de novo cell differentiation. PMID:19863756

  15. Proteomic analysis of somatic embryogenesis in Vitis vinifera.

    PubMed

    Marsoni, Milena; Bracale, Marcella; Espen, Luca; Prinsi, Bhakti; Negri, Alfredo S; Vannini, Candida

    2008-02-01

    Two dimensional gel electrophoresis coupled to mass spectrometry has been used to study the somatic embryogenesis in Vitis vinifera, by comparing embryogenic and non embryogenic calluses of the Thompson seedless cv. More than 1,000 spots were reproducibly resolved in colloidal Coomassie brilliant blue stained gels over a pI nonlinear range of 3-10 in the first dimension and using homogeneous 12.5% polyacrylamide gels in the second dimension. The expression pattern of 35 spots differed significantly between the two samples. These spots were processed by mass spectrometry analysis and the protein identity was assigned by using both the non-redundant protein and EST databases. Several responsive proteins, some already known to be involved in the somatic embryogenesis process while others, for the first time put into relation with this process, have been described. Moreover, they have been subdivided in functional categories, and their putative role is discussed in terms of their relevance in the somatic embryogenesis process. PMID:17874111

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

    PubMed

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

    1996-01-01

    The plant regeneration ability of callus obtained from zygotic embryos of the monocot Alstroemeria spp. was studied. The best explants for somatic embryogenesis were immature zygotic embryos in half-ovules when the endosperm was still soft and white. For 2 genotypes embryogenic callus was induced on callus induction medium with a success rate of 54%. The best callus induction period was 10 weeks. The morphology of embryogenic callus was nodular. Somatic embryos were formed after transfer of the callus to regeneration medium. These somatic embryos revealed later on the typical features of zygotic Alstroemeria embryos. The total duration of the plant regeneration protocol, from inoculation till rooted plantlets ready for transfer to the greenhouse, was 28 weeks. PMID:24178361

  17. Plant regeneration via somatic embryogenesis and shoot organogenesis from immature cotyledons of Camellia nitidissima Chi.

    PubMed

    Lü, Jinfeng; Chen, Rong; Zhang, Muhan; da Silva, Jaime A Teixeira; Ma, Guohua

    2013-09-01

    Camellia nitidissima Chi (Theaceae) is a world-famous economic and ornamental plant with golden-yellow flowers. It has been classified as one of the rarest and most endangered plants in China. Our objective was to induce somatic embryogenesis, shoot organogenesis and plant regeneration for C. nitidissima. Three types of callus (whitish, reddish and yellowish) were induced from immature cotyledons on improved woody plant medium (WPM) with different plant growth regulators (PGRs). Among the callus, whitish callus was induced by 4.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and reddish and yellowish callus were induced by strongly active cytokinins, thidiazuron (TDZ) or 6-benzylaminopurine (BAP), singly or combined with weakly active auxin, α-naphthaleneacetic acid (NAA). The embryogenic callus could differentiate into somatic embryos, nodular embryogenic structures (large embryo-like structures) or adventitious shoots depending on the PGR used in WPM. BAP was best for adventitious buds and zeatin was best for somatic embryogenesis while kinetin (Kt) was best for the formation of nodular embryogenic structures. The three regeneration pathways often occurred in the same embryogenic callus clumps. Most shoots (80.0%) developed roots in WPM supplemented with 24.6 μM IBA and 0.3 μM NAA while 47.5% of somatic embryos could germinate directly and develop into plantlets on induction medium supplemented with 0.9 μM BAP and 0.1 μM NAA. The nodular embryogenic structures could be sub-cultured and cyclically developed in one of two differentiation pathways: shoot organogenesis or somatic embryogenesis. Plantlets derived from shoot buds rooted and somatic embryos germinated when transplanted into soil in a greenhouse; 66.7% of plantlets from shoot culture and 78.6% of plantlets from somatic embryos survived after 8 weeks' acclimatization. PMID:23790533

  18. 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...

  19. Somatic embryogenesis of a wild passion fruit species Passiflora cincinnata Masters: histocytological and histochemical evidences.

    PubMed

    Rocha, Diego Ismael; Vieira, Lorena Melo; Tanaka, Francisco André Ossamu; da Silva, Luzimar Campos; Otoni, Wagner Campos

    2012-07-01

    The characterization of cellular changes that occur during somatic embryogenesis is essential for understanding the factors involved in the transition of somatic cells into embryogenically competent cells and determination of cells and/or tissues involved. The present study describes the anatomical and ultrastructural events that lead to the formation of somatic embryos in the model system of the wild passion fruit (Passiflora cincinnata). Mature zygotic embryos were inoculated in Murashige and Skoog induction media supplemented with 2,4-dichlorophenoxyacetic acid and 6-benzyladenine. Zygotic embryo explants at different development stages were collected and processed by conventional methods for studies using light, scanning, and transmission electron microscopy (TEM). Histochemical tests were used to examine the mobilization of reserves. The differentiation of the somatic embryos began in the abaxial side of the cotyledon region. Protuberances were formed from the meristematic proliferation of the epidermal and mesophyll cells. These cells had large nuclei, dense cytoplasm with a predominance of mitochondria, and a few reserve compounds. The protuberances extended throughout the abaxial surface of the cotyledons. The ongoing differentiation of peripheral cells of these structures led to the formation of proembryogenic zones, which, in turn, dedifferentiated into somatic embryos of multicellular origin. In the initial stages of embryogenesis, the epidermal and mesophyll cells showed starch grains and less lipids and protein reserves than the starting explant. These results provide detailed information on anatomical and ultrastructural changes involved in the acquisition of embryogenic competence and embryo differentiation that has been lacking so far in Passiflora. PMID:21927886

  20. 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

  1. 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

  2. Decoding regulatory landscape of somatic embryogenesis reveals differential regulatory networks between japonica and indica rice subspecies

    PubMed Central

    Indoliya, Yuvraj; Tiwari, Poonam; Chauhan, Abhisekh Singh; Goel, Ridhi; Shri, Manju; Bag, Sumit Kumar; Chakrabarty, Debasis

    2016-01-01

    Somatic embryogenesis is a unique process in plants and has considerable interest for biotechnological application. Compare to japonica, indica rice has been less responsive to in vitro culture. We used Illumina Hiseq 2000 sequencing platform for comparative transcriptome analysis between two rice subspecies at six different developmental stages combined with a tag-based digital gene expression profiling. Global gene expression among different samples showed greater complexity in japonica rice compared to indica which may be due to polyphyletic origin of two rice subspecies. Expression pattern in initial stage indicate major differences in proembryogenic callus induction phase that may serve as key regulator to observe differences between both subspecies. Our data suggests that phytohormone signaling pathways consist of elaborate networks with frequent crosstalk, thereby allowing plants to regulate somatic embryogenesis pathway. However, this crosstalk varies between the two rice subspecies. Down regulation of positive regulators of meristem development (i.e. KNOX, OsARF5) and up regulation of its counterparts (OsRRs, MYB, GA20ox1/GA3ox2) in japonica may be responsible for its better regeneration and differentiation of somatic embryos. Comprehensive gene expression information in the present experiment may also facilitate to understand the monocot specific meristem regulation for dedifferentiation of somatic cell to embryogenic cells. PMID:26973288

  3. Decoding regulatory landscape of somatic embryogenesis reveals differential regulatory networks between japonica and indica rice subspecies.

    PubMed

    Indoliya, Yuvraj; Tiwari, Poonam; Chauhan, Abhisekh Singh; Goel, Ridhi; Shri, Manju; Bag, Sumit Kumar; Chakrabarty, Debasis

    2016-01-01

    Somatic embryogenesis is a unique process in plants and has considerable interest for biotechnological application. Compare to japonica, indica rice has been less responsive to in vitro culture. We used Illumina Hiseq 2000 sequencing platform for comparative transcriptome analysis between two rice subspecies at six different developmental stages combined with a tag-based digital gene expression profiling. Global gene expression among different samples showed greater complexity in japonica rice compared to indica which may be due to polyphyletic origin of two rice subspecies. Expression pattern in initial stage indicate major differences in proembryogenic callus induction phase that may serve as key regulator to observe differences between both subspecies. Our data suggests that phytohormone signaling pathways consist of elaborate networks with frequent crosstalk, thereby allowing plants to regulate somatic embryogenesis pathway. However, this crosstalk varies between the two rice subspecies. Down regulation of positive regulators of meristem development (i.e. KNOX, OsARF5) and up regulation of its counterparts (OsRRs, MYB, GA20ox1/GA3ox2) in japonica may be responsible for its better regeneration and differentiation of somatic embryos. Comprehensive gene expression information in the present experiment may also facilitate to understand the monocot specific meristem regulation for dedifferentiation of somatic cell to embryogenic cells. PMID:26973288

  4. 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

  5. Somatic Embryogenesis and Plant Regeneration in Sapindus mukorossi Gaertn. from Leaf-Derived Callus Induced with 6-Benzylaminopurine.

    PubMed

    Singh, Reetika; Rai, Manoj Kumar; Kumari, Nishi

    2015-09-01

    A somatic embryogenesis system was developed for Sapindus mukorossi Gaertn. from leaf explants obtained from fresh flushes of a mature tree. Callus was induced from the midrib region of leaf explants on Murashige and Skoog (MS) medium containing different concentrations of 2,4-dichlorophenoxyacetic acid or 6-benzylaminopurine. Callus induction and somatic embryogenesis was significantly influenced by the size, physiological age, and orientation of leaf explants on the culture medium and plant growth regulators. Adaxial-side-up orientation of leaf explants significantly promoted embryogenesis in comparison with abaxial-side-up orientation. Maximum number of somatic embryos was induced on MS medium supplemented with 8.88 μM 6-benzylaminopurine. Scanning electron microscopy of embryogenic callus revealed somatic embryo origin and the development of globular-, heart-, and cotyledonary-stage somatic embryos. The frequency of maturation as well as germination of somatic embryos was higher on MS medium containing 8.88 μM 6-benzylaminopurine than on medium without 6-benzylaminopurine. Plantlets which developed from somatic embryos were acclimatized successfully with 90 % survival. PMID:26208689

  6. Improved protocol for somatic embryogenesis and calcium alginate encapsulation in Anethum graveolens L.: a medicinal herb.

    PubMed

    Dhir, Richa; Shekhawat, G S; Alam, Afroz

    2014-08-01

    An improved procedure has been developed for efficient somatic embryogenesis in Anethum graveolens. Green friable embryogenic callus was obtained from hypocotyl segments on medium augmented with 2,4-dichlorophenoxyacetic acid (2,4-D). The highest embryogenic callus induction frequency of 87 % was obtained on Murashige and Skoog (MS) medium containing 1.13 μM 2,4-D. At lower concentration of 2,4-D (0.34 μM) callus turned dark in color and slow growing. Embryogenic cultures (76 %) responded with a mean number of 43 globular and 18 heart stage embryos. Somatic embryo maturation and subsequent conversion into plantlets took place on MS lacking growth regulators. Maximum number of somatic embryos developed on MS medium was 128.3 (per flask) and a plantlet conversion of 82 % was observed. Calcium alginate beads were produced by encapsulating somatic embryos. Highest percent germination (83 %) was observed on 0.8 % agar solidified MS medium with the plantlets acquiring an average length of 2.1 cm. Encapsulated somatic embryos could be stored at 4 °C up to 60 days with a conversion frequency of 49.3 %. Highest protein and proline content has been observed in embryogenic callus with small globular embryos. During morphological differentiation of the somatic embryos, changes in the antioxidant enzymatic system were observed. Superoxide dismutase (SOD) activity increased during initial stages and decreased catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) activities were detected. PMID:24974170

  7. 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

  8. 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 μM 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

  9. Somatic embryogenesis pathway for plant regeneration in Qinjiao (Gentiana macrophylla Pall.).

    PubMed

    Chen, Li Yu; Xu, Zi Qin

    2007-08-01

    Qinjiao (Gentiana macrophylla Pall.) is a perennial herbage native to northwestern China. It has been taken as a kind of Chinese herbs for more than one thousand years. The major secondary metabolite named as gentiopicroside accounts for 8% of the dry weight of roots. It has been used for medical purpose in the treatment with rheumatism, osteoarthritis, inflammatory or ulceration. Conventionally, Qinjiao is propagated by seeds, but the seeds should be planted in one year after harvesting and the germination rate is extremely low. These confine its spread by seeds after year-round storage. Therefore, plant regeneration from somatic cells will be an ideal way for its propagation. Plant regeneration from somatic cell can be divided into two ways: somatic embryogenesis and organogenesis. Similar to zygotic embryo, somatic embryo has a bipolar structure with both shoot and root poles. Somatic embryogenesis also goes through the same key stages as globular-, heart-, torpedo- and cotyledon-stages Somatic embryogenesis was first observed in carrot callus cells more than 45 years ago. Since then, plant regeneration via somatic embryogenesis has been studied in many important species. Though the plant regeneration of Qinjiao has been previously studied, there is no investigation of somatic embryogenesis reported in this plant. Therefore, the aim of our experiment is to confirm the somatic embryogenesis pathway of plant regeneration in Qinjiao. PMID:17966465

  10. Stress-induced somatic embryogenesis in vegetative tissues of Arabidopsis thaliana.

    PubMed

    Ikeda-Iwai, Miho; Umehara, Mikihisa; Satoh, Shinobu; Kamada, Hiroshi

    2003-04-01

    Somatic embryogenesis is an obvious experimental evidence of totipotency, and is used as a model system for studying the mechanisms of de-differentiation and re-differentiation of plant cells. Although Arabidopsis is widely used as a model plant for genetic and molecular biological studies, there is no available tissue culture system for inducing somatic embryogenesis from somatic cells in this plant. We established a new tissue culture system using stress treatment to induce somatic embryogenesis in Arabidopsis. In this system, stress treatment induced formation of somatic embryos from shoot-apical-tip and floral-bud explants. The somatic embryos grew into young plantlets with normal morphology, including cotyledons, hypocotyls, and roots, and some embryo-specific genes (ABI3 and FUS3) were expressed in these embryos. Several stresses (osmotic, heavy metal ion, and dehydration stress) induced somatic embryogenesis, but the optimum stress treatment differed between different stressors. When we used mannitol to cause osmotic stress, the optimal conditions for somatic embryogenesis were 6-9 h of culture on solid B5 medium containing 0.7 m mannitol, after which the explants were transferred to B5 medium containing 2,4-dichlorophenoxyacetic acid (2,4-D, 4.5 microm), but no mannitol. Using this tissue culture system, we induced somatic embryogenesis in three major ecotypes of Arabidopsis thaliana-Ws, Col, and Ler. PMID:12662313

  11. Clonal propagation of Cyclamen persicum via somatic embryogenesis.

    PubMed

    Winkelmann, Traud

    2010-01-01

    Cyclamen (Cyclamen persicum) is an economically important ornamental pot plant with local use as cut flower as well. Traditionally, it is propagated via seeds, but interest is given in vegetative propagation of parental lines as well as superior single plants. Somatic embryogenesis is an efficient in vitro propagation method for many cyclamen cultivars. Starting from ovules of unpollinated flowers, callus is induced and propagated in a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) and 6-(gamma,gamma-dimethylallylamino)purine (2iP). Transfer to hormone-free medium results in the differentiation of somatic embryos, which afterwards germinate on the same medium. These first culture stages take about 6-7 months and are carried out in complete darkness. Two to four months after the transfer to light, plantlets develop which can be acclimatized in the greenhouse. The regenerated plants are characterized by low percentages of somaclonal variation. This protocol has proven useful not only for clonal propagation, but also for artificial seed preparation, cryopreservation, genetic transformation and protoplast regeneration. PMID:20099110

  12. In vitro somatic embryogenesis and plantlet regeneration from immature male inflorescence of adult dura and tenera palms of Elaeis guineensis (Jacq.).

    PubMed

    Jayanthi, Madhavan; Susanthi, Bollarapu; Murali Mohan, Nandiganti; Mandal, Pranab Kumar

    2015-01-01

    We report here a method for plant regeneration through somatic embryogenesis from explants collected from immature male inflorescence of adult oil palm cultivated in India. Callus induction was successful from tissues of immature male inflorescence collected from both dura and tenera varieties of oil palm. A modified Y3 (Eeuwens) media supplemented with several additives and activated charcoal (3%) were used for the experiments. Out of four different auxin treatments, 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid (picloram) produced maximum callus induction (82%) and it was not significantly different from 2,4-dichlorophenoxyacetic acid (2,4-D) and a combination of 2,4-D + picloram. The callus induction obtained with auxin α-naphthalene acetic acid was only 54% and it was significantly low as compared to the other treatments. Highest embryogenesis was obtained with a combination of 2,4-D + picloram (4.9%) followed by picloram (3.4%). Genotypic variation in response to the same auxins was observed both for callus induction and embryogenesis. Callus induction and embryogenesis ranged from 42 to 72% and 6.8 to 9.35%, respectively in tenera. The formation of embryogenic calli was marked by the appearance of white to yellowish globular or nodular structures which subsequently formed clear somatic embryos. Somatic embryogenesis was asynchronous and at one time we could find different stages of embryogenesis like the globular, torpedo and the cotyledonary stages. The somatic embryos when exposed to light in the same basal media along with 6-benzyladenine (18 µM), abscisic acid (3.78 µM) and gibberellic acid (5.78 µM) regenerated into plantlets. To the best of our knowledge this is the first report o f callus induction and somatic embryogenesis from immature male inflorescence of oil palm. PMID:26085976

  13. 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

  14. Somatic embryogenesis in cultured immature zygotic embryos and leaf protoplasts of Arabidopsis thaliana ecotypes.

    PubMed

    Luo, Y; Koop, H U

    1997-01-01

    Immature zygotic embryos of six ecotypes (Nd-0, Ler, C24, Col-0, Nossen, Ws-2) of Arabidopsis thaliana (L.) Heynh. were cultured in vitro. The same ecotypes, except Nossen, were used for studies on leaf protoplast culture. Experimental conditions for the induction of somatic embryos were established in both culture systems. In the case of immature zygotic embryos, the parameters investigated were the influence of developmental stage of the explant, the ecotypes used, and various concentrations and combinations of growth regulatory substances (phytohormones). In the ecotype Ler, structures were discovered which were very similar to those found in the early stages of zygotic embryo-genesis: globular structures at the end of a suspensor-like single file of cells were frequently observed. In the case of leaf protoplasts, high efficiencies of colony formation and plant regeneration occurred in Ws-2 and C24. A novel type of cell division pattern was found in Col-0 and C24, again highly reminiscent of the early division patterns in zygotic embryos. Similarities and differences between zygotic and somatic embryogenesis are discussed. PMID:9232908

  15. Genetic variability of somatic embryogenesis in tissue cultures of sugar beet breeding lines.

    PubMed

    Golovko, A

    2001-01-01

    Genetic variability of callus initiation and plant regeneration has been investigated among three sugar beet genotypes. It was found that TDZ has a genotype-independent effect on callus initiation and is responsible for more than a two-fold increase in the friable callus induction rate and more than a three-fold increase in the shoot regeneration rate from this callus. Along with the genotype-independent organogenesis, regeneration from callus occasionally went through the process of somatic embryogenesis in a highly genotype-specific manner. Despite fast and uncontrollable conversion of embryos to normal plants, it was possible to select and maintain repetitive embryogenic culture without loosing regeneration and root formation capabilities. Extensive experimenting with medium composition and culture conditions resulted in an optimal medium for maintenance of repetitive embryos. Comparing with BAP, low concentrations of TDZ provide higher level of adventitious shoot formation and do not induce vitrification of tissues. PMID:11944321

  16. Moderate stress responses and specific changes in polyamine metabolism characterize Scots pine somatic embryogenesis.

    PubMed

    Salo, Heikki M; Sarjala, Tytti; Jokela, Anne; Häggman, Hely; Vuosku, Jaana

    2016-03-01

    Somatic embryogenesis (SE) is one of the methods with the highest potential for the vegetative propagation of commercially important coniferous species. However, many conifers, including Scots pine (Pinus sylvestris L.), are recalcitrant to SE and a better understanding of the mechanisms behind the SE process is needed. In Scots pine SE cultures, embryo production is commonly induced by the removal of auxin, addition of abscisic acid (ABA) and the desiccation of cell masses by polyethylene glycol (PEG). In the present study, we focus on the possible link between the induction of somatic embryo formation and cellular stress responses such as hydrogen peroxide protection, DNA repair, changes in polyamine (PA) metabolism and autophagy. Cellular PA contents and the expression of the PA metabolism genes arginine decarboxylase (ADC), spermidine synthase (SPDS), thermospermine synthase (ACL5) and diamine oxidase (DAO) were analyzed, as well as the expression of catalase (CAT), DNA repair genes (RAD51, KU80) and autophagy-related genes (ATG5, ATG8) throughout the induction of somatic embryo formation in Scots pine SE cultures. Among the embryo-producing SE lines, the expression of ADC, SPDS, ACL5, DAO, CAT, RAD51, KU80 and ATG8 showed consistent profiles. Furthermore, the overall low expression of the stress-related genes suggests that cells in those SE lines were not stressed but recognized the ABA+PEG treatment as a signal to trigger the embryogenic pathway. In those SE lines that were unable to produce embryos, cells seemed to experience the ABA+PEG treatment mostly as osmotic stress and activated a wide range of stress defense mechanisms. Altogether, our results suggest that the direction to the embryogenic pathway is connected with cellular stress responses in Scots pine SE cultures. Thus, the manipulation of stress response pathways may provide a way to enhance somatic embryo production in recalcitrant Scots pine SE lines. PMID:26786537

  17. Analysis of the rolC promoter region involved in somatic embryogenesis-related activation in carrot cell cultures.

    PubMed Central

    Fujii, N; Yokoyama, R; Uchimiya, H

    1994-01-01

    In cell cultures of carrot (Daucus carota L.), somatic embryogenesis can be induced by transferring cells from a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) to one devoid of 2,4-D. Previous analysis of transgenic carrot cells containing the 5' non-coding sequence of the Ri plasmid rolC and a structural gene for bacterial beta-glucuronidase (uidA) has shown that the chimeric gene is actively expressed after induction of somatic embryogenesis. In this study, we demonstrate that activation of the rolC promoter is dependent on the process of embryo development but not on the duration of the cell culture in 2,4-D-free medium. We also analyzed the cis region of the rolC promoter that is responsible for somatic embryogenesis-related activation (SERA), namely relatively low beta-glucuronidase (GUS) activity in calli and proembryogenic masses (PEM) and high GUS activity in heart- and torpedo-stage embryos. When the -255-bp region of the rolC gene was used, SERA was retained. Internal deletions within this -255-bp region did not alter SERA by the rolC promoter. Furthermore, when a rolC promoter fragment (-848 to -94 bp) was fused to the cauliflower mosaic virus (CaMV) 35S core region (-90 to +6 bp), it conferred relatively low GUS activity in calli and PEM but high GUS activity in heart and torpedo embryos. When -848 to -255-bp or -255- to -94-bp fragments of the rolC promoter were fused to the same CaMV 35S core region, GUS activity patterns were not related to somatic embryogenesis. These results suggest that the combination of several regulatory regions in the rolC promoter may be required for SERA in carrot cell cultures. PMID:8016259

  18. Extensive Modulation of the Transcription Factor Transcriptome during Somatic Embryogenesis in Arabidopsis thaliana

    PubMed Central

    Gliwicka, Marta; Nowak, Katarzyna; Balazadeh, Salma; Mueller-Roeber, Bernd; Gaj, Malgorzata D.

    2013-01-01

    Molecular mechanisms controlling plant totipotency are largely unknown and studies on somatic embryogenesis (SE), the process through which already differentiated cells reverse their developmental program and become embryogenic, provide a unique means for deciphering molecular mechanisms controlling developmental plasticity of somatic cells. Among various factors essential for embryogenic transition of somatic cells transcription factors (TFs), crucial regulators of genetic programs, are believed to play a central role. Herein, we used quantitative real-time polymerase chain reaction (qRT-PCR) to identify TF genes affected during SE induced by in vitro culture in Arabidopsis thaliana. Expression profiles of 1,880 TFs were evaluated in the highly embryogenic Col-0 accession and the non-embryogenic tanmei/emb2757 mutant. Our study revealed 729 TFs whose expression changes during the 10-days incubation period of SE; 141 TFs displayed distinct differences in expression patterns in embryogenic versus non-embryogenic cultures. The embryo-induction stage of SE occurring during the first 5 days of culture was associated with a robust and dramatic change of the TF transcriptome characterized by the drastic up-regulation of the expression of a great majority (over 80%) of the TFs active during embryogenic culture. In contrast to SE induction, the advanced stage of embryo formation showed attenuation and stabilization of transcript levels of many TFs. In total, 519 of the SE-modulated TFs were functionally annotated and transcripts related with plant development, phytohormones and stress responses were found to be most abundant. The involvement of selected TFs in SE was verified using T-DNA insertion lines and a significantly reduced embryogenic response was found for the majority of them. This study provides comprehensive data focused on the expression of TF genes during SE and suggests directions for further research on functional genomics of SE. PMID:23874927

  19. Interruption of Somatic Embryogenesis in Daucus carota L. by 5-Bromodeoxyuridine

    PubMed Central

    Thomas, John C.; Nessler, Craig; Katterman, Frank

    1989-01-01

    Embryogenic Daucus carota L. cells grown in 9 micromolar 2.4-dichlorophenoxyacetic acid are resistant to greater than 5 micromolar 5-bromodeoxyuridine (BrdU). In contrast, 5 micromolar BrdU strongly inhibits somatic embryogenesis within 24 hours after transfer of cells to an auxin-free medium. DNA synthesis rates in control and BrdU-treated cultures are rapid and similar; however, the DNA content does not reach levels as great in the presence of BrdU as in control cultures. BrdU substitutes for thymidine in the DNA in 28% of the available sites 48 hours after auxin removal. Following DNA repair, somatic embryogenesis resumes. BrdU DNA incorporation leads to somatic embryogenesis inhibition and provides an alternative to auxin treatment for the interruption of carrot cell culture differentiation. Images Figure 2 Figure 3 Figure 7 PMID:16666898

  20. Regeneration by somatic embryogenesis of triploid plants from endosperm of walnut, Juglans regia L. cv Manregian.

    PubMed

    Tulecke, W; McGranahan, G; Ahmadi, H

    1988-08-01

    Plants were regenerated by somatic embryogenesis from endosperm tissue of open-pollinated seeds of Juglans regia L. cv Manregian. These plants were obtained by growing endosperm tissue on media similar to those used for plant regeneration from walnut cotyledons (Tulecke and McGranahan 1985). The plants appear morphologically uniform and have a triploid chromosome number of 3n=48. Nine plants have been grown to a young sapling stage in soil. This embryogenic line from endosperm has been maintained in culture for two years by the process of repetitive somatic embryogenesis. PMID:24241869

  1. Analysis of genetic stability at SSR loci during somatic embryogenesis in maritime pine (Pinus pinaster).

    PubMed

    Marum, Liliana; Rocheta, Margarida; Maroco, João; Oliveira, M Margarida; Miguel, Célia

    2009-04-01

    Somatic embryogenesis (SE) is a propagation tool of particular interest for accelerating the deployment of new high-performance planting stock in multivarietal forestry. However, genetic conformity in in vitro propagated plants should be assessed as early as possible, especially in long-living trees such as conifers. The main objective of this work was to study such conformity based on genetic stability at simple sequence repeat (SSR) loci during somatic embryogenesis in maritime pine (Pinus pinaster Ait.). Embryogenic cell lines (ECLs) subjected to tissue proliferation during 6, 14 or 22 months, as well as emblings regenerated from several ECLs, were analyzed. Genetic variation at seven SSR loci was detected in ECLs under proliferation conditions for all time points, and in 5 out of 52 emblings recovered from somatic embryos. Three of these five emblings showed an abnormal phenotype consisting mainly of plagiotropism and loss of apical dominance. Despite the variation found in somatic embryogenesis-derived plant material, no correlation was established between genetic stability at the analyzed loci and abnormal embling phenotype, present in 64% of the emblings. The use of microsatellites in this work was efficient for monitoring mutation events during the somatic embryogenesis in P. pinaster. These molecular markers should be useful in the implementation of new breeding and deployment strategies for improved trees using SE. PMID:19153739

  2. 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

  3. 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

  4. 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

  5. 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...

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

    PubMed

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

    2016-09-01

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

  7. Somatic embryogenesis and enhanced shoot organogenesis in Metabriggsia ovalifolia W. T. Wang.

    PubMed

    Ouyang, Yao; Chen, Yulu; Lü, Jinfeng; Teixeira da Silva, Jaime A; Zhang, Xinhua; Ma, Guohua

    2016-01-01

    An efficient protocol providing a dual regeneration pathway via direct shoot organogenesis and somatic embryogenesis for an endangered species, Metabriggsia ovalifolia W. T. Wang, was established from leaf explants. When applied at 2.5 μM, the cytokinins 6-benzyladenine (BA) or thidiazuron (TDZ) and the auxins indole-3-butyric acid (IBA), α-naphthaleneacetic acid (NAA) and indole-3-acetic acid (IAA) could induce shoots when on basal Murashige and Skoog (MS) medium. BA and TDZ could induce more adventitious shoots (19.1 and 31.2/explant, respectively) than NAA (4.6/explant), IBA (5.7/explant) or IAA (6.4/explant). BA and TDZ at 5-10 μM could induce both shoots and somatic embryos. A higher concentration of TDZ (25 μM) induced only somatic embryos (39.8/explant). The same concentration of BA induced both adventitious shoots (23.6/explant) and somatic embryos (9.7/explant). Thus, somatic embryogenesis in this plant needs a high cytokinin concentration (BA; TDZ), as evidenced by histology. Somatic embryos germinated easily when left on the same media, but formed adventitious roots in two weeks on MS supplemented with 0.5 μM NAA, 0.5 μM IBA and 0.1% activated charcoal. Over 93% of plantlets survived following acclimatization and transfer to a mixture of sand and vermiculite (1:1, v/v) in trays. PMID:27090564

  8. Somatic embryogenesis and enhanced shoot organogenesis in Metabriggsia ovalifolia W. T. Wang

    PubMed Central

    Ouyang, Yao; Chen, Yulu; Lü, Jinfeng; Teixeira da Silva, Jaime A.; Zhang, Xinhua; Ma, Guohua

    2016-01-01

    An efficient protocol providing a dual regeneration pathway via direct shoot organogenesis and somatic embryogenesis for an endangered species, Metabriggsia ovalifolia W. T. Wang, was established from leaf explants. When applied at 2.5 μM, the cytokinins 6-benzyladenine (BA) or thidiazuron (TDZ) and the auxins indole-3-butyric acid (IBA), α-naphthaleneacetic acid (NAA) and indole-3-acetic acid (IAA) could induce shoots when on basal Murashige and Skoog (MS) medium. BA and TDZ could induce more adventitious shoots (19.1 and 31.2/explant, respectively) than NAA (4.6/explant), IBA (5.7/explant) or IAA (6.4/explant). BA and TDZ at 5–10 μM could induce both shoots and somatic embryos. A higher concentration of TDZ (25 μM) induced only somatic embryos (39.8/explant). The same concentration of BA induced both adventitious shoots (23.6/explant) and somatic embryos (9.7/explant). Thus, somatic embryogenesis in this plant needs a high cytokinin concentration (BA; TDZ), as evidenced by histology. Somatic embryos germinated easily when left on the same media, but formed adventitious roots in two weeks on MS supplemented with 0.5 μM NAA, 0.5 μM IBA and 0.1% activated charcoal. Over 93% of plantlets survived following acclimatization and transfer to a mixture of sand and vermiculite (1:1, v/v) in trays. PMID:27090564

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

    PubMed

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

    1998-06-01

    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

  10. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  12. Regulation of organogenesis and somatic embryogenesis by auxin in melon, Cucumis melo L.

    PubMed

    Tabei, Y; Kanno, T; Nishio, T

    1991-08-01

    Various tissues of seeds and seedlings of melon were cultured in vitro to study the effects of auxin concentration on organogenesis and embryogenesis. Adventitious shoots and somatic embryos were formed from explants of cotyledons of mature seeds, hypocotyls of seedlings, and leaves and petioles of young plantlets. Expanded cotyledons of seedlings formed only adventitious shoots. All tissues responded similarly to the 2,4-D concentration in the media, that is, adventitious shoots were formed at low concentration, callus proliferated without differentiation at intermediate concentration and somatic embryos were induced at high concentration. Cotyledons of mature seeds formed both adventitious shoots and somatic embryos more efficiently than any other tissues cultured.Effects of three auxins, 2,4-D, NAA and IAA, on organogenesis and embryogenesis were compared using cotyledons of mature seeds. Adventitious shoots were formed at low level of auxins (0 to 0.01 mg/l 2,4-D; 0 to 0.1 mg/l NAA; 0 to 1.0 mg/l IAA), and embryos were formed at high level of auxins (1.0 to 2.0 mg/l 2,4-D; 3.0 to 10.0 mg/l NAA; 20.0 to 100.0 mg/l IAA). IAA gave more efficient shoot formation and embryogenesis than the other auxins. PMID:24221584

  13. 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

  14. Arabinogalactan-proteins stimulate somatic embryogenesis and plant propagation of Pelargonium sidoides.

    PubMed

    Duchow, Stefanie; Dahlke, Renate I; Geske, Thomas; Blaschek, Wolfgang; Classen, Birgit

    2016-11-01

    Root extracts of the medicinal plant Pelargonium sidoides, native to South Africa, are used globally for the treatment of common cold and cough. Due to an increasing economic commercialization of P. sidoides remedies, wild collections of root material should be accompanied by effective methods for plant propagation like somatic embryogenesis. Based on this, the influence of arabinogalactan-proteins (AGPs) on somatic embryogenesis and plant propagation of P. sidoides has been investigated. High-molecular weight AGPs have been isolated from dried roots as well as from cell cultures of P. sidoides with yields between 0.1% and 0.9%, respectively. AGPs are characterized by a 1,3-linked Galp backbone, branched at C6 to 1,6-linked Galp side chains terminated by Araf and to a minor extent by GlcpA, Galp or Rhap. Treatment of explants of P. sidoides with AGPs from roots or suspension culture over 5.5 weeks resulted in effective stimulation of somatic embryo development and plant regeneration. PMID:27516259

  15. Influence of low temperature preincubation on somatic embryogenesis and ethylene emanation from orchardgrass leaves

    NASA Technical Reports Server (NTRS)

    Tomaszewski, Z. Jr; Kuklin, A. I.; Sams, C. E.; Conger, B. V.

    1994-01-01

    The objectives of this study were to determine the effects of low temperature (4 degrees C) preincubation on somatic embryogenesis from orchardgrass (Dactylis glomerata L.) leaf cultures and to relate these effects to ethylene emanation during the preincubation and incubation periods. Experiments were also conducted with an ethylene biosynthesis inhibitor aminooxyacetic acid (AOA). Segments from the innermost two leaves were cultured on SH medium with 30 micromoles dicamba at 4 degrees C for 1 to 7 d before transfer to 21 degrees C. Results from a paired design showed that the embryogenic response of leaf segments preincubated at 4 degrees C was equal or superior to nonpreincubated leaves at all time periods. Ethylene emanation was decreased during the low temperature incubation. Transfer of leaf segments from 4 degrees C to 21 degrees C was accompanied by a burst of ethylene which rose to control levels within 30 min. AOA at 20 and 40 micromoles decreased ethylene emanation but did not stimulate the embryogenic response. We conclude that the stimulation of somatic embryogenesis by low temperature is probably due to factors other than suppression of ethylene biosynthesis.

  16. AGAMOUS-Like15 Promotes Somatic Embryogenesis in Arabidopsis and Soybean in Part by the Control of Ethylene Biosynthesis and Response1[C][W][OA

    PubMed Central

    Zheng, Qiaolin; Zheng, Yumei; Perry, Sharyn E.

    2013-01-01

    Many of the regulatory processes occurring during plant embryogenesis are still unknown. Relatively few cells are involved, and they are embedded within maternal tissues, making this developmental phase difficult to study. Somatic embryogenesis is a more accessible system, and many important regulatory genes appear to function similar to zygotic development, making somatic embryogenesis a valuable model for the study of zygotic processes. To better understand the role of the Arabidopsis (Arabidopsis thaliana) MADS factor AGAMOUS-Like15 (AGL15) in the promotion of somatic embryogenesis, direct target genes were identified by chromatin immunoprecipitation-tiling arrays and expression arrays. One potential directly up-regulated target was At5g61590, which encodes a member of the ethylene response factor subfamily B-3 of APETALA2/ETHYLENE RESPONSE FACTOR transcription factors and is related to Medicago truncatula SOMATIC EMBRYO-RELATED FACTOR1 (MtSERF1), which has been shown to be required for somatic embryogenesis in M. truncatula. Here, we report confirmation that At5g61590 is a directly expressed target of AGL15 and that At5g61590 is essential for AGL15’s promotion of somatic embryogenesis. Because At5g61590 is a member of the ETHYLENE RESPONSE FACTOR family, effects of ethylene on somatic embryogenesis were investigated. Precursors to ethylene stimulate somatic embryogenesis, whereas inhibitors of ethylene synthesis or perception reduce somatic embryogenesis. To extend findings to a crop plant, we investigated the effects of ethylene on somatic embryogenesis in soybean (Glycine max). Furthermore, we found that a potential ortholog of AGL15 in soybean (GmAGL15) up-regulates ethylene biosynthesis and response, including direct regulation of soybean orthologs of At5g61590/MtSERF1 named here GmSERF1 and GmSERF2, in concordance with the M. truncatula nomenclature. PMID:23457229

  17. 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. ...

  18. ROS Homeostasis Regulates Somatic Embryogenesis via the Regulation of Auxin Signaling in Cotton.

    PubMed

    Zhou, Ting; Yang, Xiyan; Guo, Kai; Deng, Jinwu; Xu, Jiao; Gao, Wenhui; Lindsey, Keith; Zhang, Xianlong

    2016-06-01

    Somatic embryogenesis (S.E.) is a versatile model for understanding the mechanisms of plant embryogenesis and a useful tool for plant propagation. To decipher the intricate molecular program and potentially to control the parameters affecting the frequency of S.E., a proteomics approach based on two-dimensional gel electrophoresis (2-DE) combined with MALDI-TOF/TOF was used. A total of 149 unique differentially expressed proteins (DEPs) were identified at different stages of cotton S.E. compared with the initial control (0 h explants). The expression profile and functional annotation of these DEPs revealed that S.E. activated stress-related proteins, including several reactive oxygen species (ROS)-scavenging enzymes. Proteins implicated in metabolic, developmental, and reproductive processes were also identified. Further experiments were performed to confirm the role of ROS-scavenging enzymes, suggesting the involvement of ROS homeostasis during S.E. in cotton. Suppressing the expression of specifically identified GhAPX proteins resulted in the inhibition of dedifferentiation. Accelerated redifferentiation was observed in the suppression lines of GhAPXs or GhGSTL3 in parallel with the alteration of endogenous ascorbate metabolism and accumulation of endogenous H2O2 content. Moreover, disrupting endogenous redox homeostasis through the application of high concentrations of DPI, H2O2, BSO, or GSH inhibited the dedifferentiation of cotton explants. Mild oxidation induced through BSO treatment facilitated the transition from embryogenic calluses (ECs) to somatic embryos. Meanwhile, auxin homeostasis was altered through the perturbation of ROS homeostasis by chemical treatments or suppression of ROS-scavenging proteins, along with the activating/suppressing the transcription of genes related to auxin transportation and signaling. These results show that stress responses are activated during S.E. and may regulate the ROS homeostasis by interacting with auxin signaling

  19. Histological analysis of indirect somatic embryogenesis in the Marsh clubmoss Lycopodiella inundata (L.) Holub (Pteridophytes).

    PubMed

    Atmane; Blervacq; Michaux-Ferriere; Vasseur

    2000-07-28

    An efficient in vitro plant regeneration method was developed for Lycopodiella inundata (L.) Holub, an endangered medicinal Lycopod (Pteridophytes). Vegetative apices were used as explant material. Nodular calluses were established after three cycles (13 weeks each) on a medium containing a few minerals and organic compounds and supplemented with 0.05 µM 3-indolebutyric acid (IBA) and 1.4 µM kinetin (Kin). Propagation was achieved every 13 weeks on this callus medium (CM). When nodular calluses were transferred on a medium supplemented with 2.5 µM IBA and 0.33 µM gibberellic acid (GA(3)) designated as embryogenic medium (EM), organized structures appeared and developed into plantlets. Development phases were characterized by histological studies. Some phases of zygotic embryogenesis previously described for Lycopods were observed in L. inundata. Histological analyses established that an indirect somatic embryo was derived from a single embryogenic cell by following the zygotic developmental pathway. As this phenomenon has not previously been reported in Lycopods, a comparison between somatic and zygotic embryos is discussed based upon morphology and histology. PMID:10936522

  20. Transcriptome profiling and digital gene expression by deep sequencing in early somatic embryogenesis of endangered medicinal Eleutherococcus senticosus Maxim.

    PubMed

    Tao, Lei; Zhao, Yue; Wu, Ying; Wang, Qiuyu; Yuan, Hongmei; Zhao, Lijuan; Guo, Wendong; You, Xiangling

    2016-03-01

    Somatic embryogenesis (SE) has been studied as a model system to understand molecular events in physiology, biochemistry, and cytology during plant embryo development. In particular, it is exceedingly difficult to access the morphological and early regulatory events in zygotic embryos. To understand the molecular mechanisms regulating early SE in Eleutherococcus senticosus Maxim., we used high-throughput RNA-Seq technology to investigate its transcriptome. We obtained 58,327,688 reads, which were assembled into 75,803 unique unigenes. To better understand their functions, the unigenes were annotated using the Clusters of Orthologous Groups, Gene Ontology, and Kyoto Encyclopedia of Genes and Genomes databases. Digital gene expression libraries revealed differences in gene expression profiles at different developmental stages (embryogenic callus, yellow embryogenic callus, global embryo). We obtained a sequencing depth of >5.6 million tags per sample and identified many differentially expressed genes at various stages of SE. The initiation of SE affected gene expression in many KEGG pathways, but predominantly that in metabolic pathways, biosynthesis of secondary metabolites, and plant hormone signal transduction. This information on the changes in the multiple pathways related to SE induction in E. senticosus Maxim. embryogenic tissue will contribute to a more comprehensive understanding of the mechanisms involved in early SE. Additionally, the differentially expressed genes may act as molecular markers and could play very important roles in the early stage of SE. The results are a comprehensive molecular biology resource for investigating SE of E. senticosus Maxim. PMID:26657036

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

    PubMed

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

    2016-10-01

    Somatic embryogenesis and organogenesis in Lilium pumilum were successfully regulated by picloram, α-naphthaleneacetic acid (NAA), and 6-benzyladenine (BA). In organogenesis, the highest shoot regeneration frequency (92.5%) was obtained directly from bulb scales on Murashige and Skoog (MS) medium containing 2.0 mg L(-1) BA and 0.2 mg L(-1) NAA, while organogenic callus (OC) formed from leaves on MS medium supplemented with 1.0 mg L(-1) BA and 0.5 mg L(-1) NAA. Following subculture, 76.7% of OC regenerated shoots. In somatic embryogenesis, the combination of picloram and NAA increased the amount of embryogenic callus (EC) that formed with a maximum on 90.7% of all explants which formed 11 somatic embryos (SEs) per explant. Differences between EC and OC in cellular morphology and cell differentiation fate were easily observed. SEs initially formed via an exogenous or an endogenous origin. The appearance of a protoderm in heart-shaped SE and the bipolar shoot-root development in oval-shaped SE indicated true somatic embryogenesis. This protocol provides a new and detailed regulation and histological examination of regeneration pattern in L. pumilum. PMID:27285948

  2. Stage and tissue-specific modulation of ten conserved miRNAs and their targets during somatic embryogenesis of Valencia sweet orange.

    PubMed

    Wu, Xiao-Meng; Liu, Mei-Ya; Ge, Xiao-Xia; Xu, Qiang; Guo, Wen-Wu

    2011-03-01

    Somatic embryogenesis (SE) is a remarkable process of plant somatic cells developing into an embryo capable of forming a complete plant. MiRNAs play important roles in plant development by regulating expression of their target genes, but its function in SE has rarely been studied. Herein, ten conserved miRNAs with critical functions in plant development are detected by stem-loop qRT-PCR in the SE system of Valencia sweet orange. Sixteen unigenes from citrus are predicted to be targeted by six of the miRNAs. Cleavage sites on 15 of these target mRNAs are mapped by 5'RACE, of which ten are reported in this study. Transcript abundances of the 16 target unigenes are detected by qRT-PCR during SE process. Stage and tissue-specific expressions of miRNAs and their targets suggest their possible modulation on SE of citrus callus: miR156, 168 and 171 exert regulatory function during somatic embryo induction process; miR159, 164, 390 and 397 are related to globular-shaped embryo formation; miR166, 167 and 398 are required for cotyledon-shaped embryo morphogenesis; in addition, target genes of miR164, 166 and 397 are associated with SE disability of nonembryogenic callus. Exploration of miRNA-mediated modulation on SE is expected to provide new insights into plant cell totipotency, as well as how to maintain and enhance the embryogenic capacity of somatic cells. PMID:21103993

  3. Analysis of trace elements during different developmental stages of somatic embryogenesis in Plantago ovata Forssk using energy dispersive X-ray fluorescence.

    PubMed

    Saha, Priyanka; Raychaudhuri, Sarmistha Sen; Sudarshan, Mathummal; Chakraborty, Anindita

    2010-06-01

    Energy dispersive X-ray fluorescence (ED-XRF) technique has been used for the determination of trace element profile during different developmental stages of somatic embryogenic callus of an economically important medicinal plant, Plantago ovata Forssk. Somatic embryogenesis is a plant tissue culture-based technique, which is used for plant regeneration and crop improvement. In the present investigation, elemental content was analysed using ED-XRF technique during different developmental stages and also determine the effect of additives--casein hydrolysate and coconut water on the trace elemental profile of embryogenic callus tissue of P. ovata. Subsequent experiments showed significant alteration in the concentration of K, Ca, Mn, Fe, Zn, Cu, Br, and Sr in both the embryogenic and non-embryogenic callus. Higher K, Ca, Fe, Cu, and Zn accumulation was in embryogenic tissue stage compared to other stages, suggesting these elements are crucial for successful embryogenesis. The results suggest that this information could be useful for formulating a media for in vitro embryo induction of P. ovata. PMID:19696971

  4. Unusual patterns of somatic embryogenesis in the domesticated carrot: developmental effects of exogenous auxins and auxin transport inhibitors.

    PubMed

    Schiavone, F M; Cooke, T J

    1987-06-01

    The effects of various exogenous auxins and polar auxin transport inhibitors on somatic embryogenesis in carrot cultures were investigated. Indole-3-acetic acid and 2,4-dichlorophenoxyacetic acid do not disrupt the sequence or the polarity of individual stages in embryo development, but tend to cause developing embryos to revert to undifferentiated callus, with increasing frequency in later embryo stages. The transport inhibitors, N-(1-naphthyl)phthalamic acid and 2,3,5-triiodobenzoic acid, block morphological transitions to the subsequent stage; for example, they cause the formation of enlarged globular and oblong embryos. Heart embryos in these treatments usually develop additional lateral growth axes. These results shed light on the role of auxin and its polar transport in somatic embryogenesis. PMID:3607884

  5. [Investigation of molecular-genetic heterogeneity of clematis plants (Clematis L.) obtained by organogenesis and somatic embryogenesis in vitro].

    PubMed

    Mitrofanova, I V; Galaev, A V; Sivolap, Iu M

    2003-01-01

    Genome variability of in vitro micropropagated Clematis plants was established. The optimum concentrations of BAP and zeatin in the culture medium regulating in vitro morphogenetic processes in clematis explants cv. Serenada Kryma were determined. Molecular-genetic analysis of Clematis plants obtained via in vitro somatic embryogenesis and organogenesis was carried out. Using ISSR primers 105 amplicons have been revealed, six of them were polymorphic. The mean index of heterogeneity of clematis plants was 5.7%. PMID:15067940

  6. Arabidopsis SOMATIC EMBRYOGENESIS RECEPTOR KINASES1 and 2 are essential for tapetum development and microspore maturation.

    PubMed

    Colcombet, Jean; Boisson-Dernier, Aurélien; Ros-Palau, Roc; Vera, Carlos E; Schroeder, Julian I

    2005-12-01

    Among the >200 members of the leucine-rich repeat receptor kinase family in Arabidopsis thaliana, only a few have been functionally characterized. Here, we report a critical function in anther development for the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 (SERK1) and SERK2 genes. Both SERK1 and SERK2 are expressed widely in locules until stage 6 anthers and are more concentrated in the tapetal cell layer later. Whereas serk1 and serk2 single insertion mutants did not show developmental phenotypes, serk1 serk2 double mutants were not able to produce seeds because of a lack of pollen development in mutant anthers. In young buds, double mutant anthers developed normally, but serk1 serk2 microsporangia produced more sporogenous cells that were unable to develop beyond meiosis. Furthermore, serk1 serk2 double mutants developed only three cell layers surrounding the sporogenous cell mass, whereas wild-type anthers developed four cell layers. Further confocal microscopic and molecular analyses showed that serk1 serk2 double mutant anthers lack development of the tapetal cell layer, which accounts for the microspore abortion and male sterility. Taken together, these findings demonstrate that the SERK1 and SERK2 receptor kinases function redundantly as an important control point for sporophytic development controlling male gametophyte production. PMID:16284306

  7. A Chimeric Arabinogalactan Protein Promotes Somatic Embryogenesis in Cotton Cell Culture1[W][OA

    PubMed Central

    Poon, Simon; Heath, Robyn Louise; Clarke, Adrienne Elizabeth

    2012-01-01

    Arabinogalactan proteins (AGPs) are a family of extracellular plant proteoglycans implicated in many aspects of plant growth and development, including in vitro somatic embryogenesis (SE). We found that specific AGPs were produced by cotton (Gossypium hirsutum) calli undergoing SE and that when these AGPs were isolated and incorporated into tissue culture medium, cotton SE was promoted. When the AGPs were partly or fully deglycosylated, SE-promoting activity was not diminished. Testing of AGPs separated by reverse-phase high-performance liquid chromatography revealed that the SE-promoting activity resided in a hydrophobic fraction. We cloned a full-length complementary DNA (cotton PHYTOCYANIN-LIKE ARABINOGALACTAN-PROTEIN1 [GhPLA1]) that encoded the protein backbone of an AGP in the active fraction. It has a chimeric structure comprising an amino-terminal signal sequence, a phytocyanin-like domain, an AGP-like domain, and a hydrophobic carboxyl-terminal domain. Recombinant production of GhPLA1 in tobacco (Nicotiana tabacum) cells enabled us to purify and analyze a single glycosylated AGP and to demonstrate that this chimeric AGP promotes cotton SE. Furthermore, the nonglycosylated phytocyanin-like domain from GhPLA1, which was bacterially produced, also promoted SE, indicating that the glycosylated AGP domain was unnecessary for in vitro activity. PMID:22858635

  8. Glutathione-S-Transferase is Detected During Somatic Embryogenesis in Chicory

    PubMed Central

    Galland, Rachel; Blervacq, Anne-Sophie; Blassiau, Christelle; Smagghe, Benoît; Decottignies, Jean-Pierre

    2007-01-01

    Glutathione S-tranferases (GSTs) are a heterogeneous family of proteins, which perform diverse pivotal catalytic and non-enzymatic functions during plant development and in plant stress responses. Previous studies have shown that a GST activity (EC 2.5.1.18) is closely linked with the precocious phases of somatic embryogenesis in leaf tissues of an interspecific chicory hybrid (Cichorium intybus L. var. sativa × C. endivia L. var. latifolia). In order to learn more about the involvement of this enzyme in this process, in situ-hybridization as well as immunolocalization were performed in parallel. GST-mRNAs and proteins were colocalized in small veins, particularly in young protoxylem cell walls. During cell reactivation, the in situ and protein signals became less intense and were associated with chloroplasts. The GST-mRNAs and corresponding proteins were not always colocalized in the same tissues. While high amounts of transcripts could be detected in multicellular embryos, the proteins were not well labeled. Our results indicated that GSTs belong to a complex anti-oxidant mechanism within the cell, and also at the cell wall level. GSTs presence in reactivated cell and multicellular embryos is discussed in relation to redox cell status. PMID:19516999

  9. Proteomic analysis of somatic embryogenesis in Valencia sweet orange (Citrus sinensis Osbeck).

    PubMed

    Pan, Zhiyong; Guan, Rui; Zhu, Shiping; Deng, Xiuxin

    2009-02-01

    Two dimensional gel electrophoresis combined with matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) was employed to study the somatic embryogenesis (SE) in Valencia sweet orange (Citrus sinensis Osbeck). Twenty-four differentially expressed proteins were identified at five time points of citrus SE (0, 1, 2, 3, 4 weeks after embryo initiation) covering globular, heart/torpedo and cotyledon-shaped embryo stages. The general expression patterns for these proteins were consistent with those appeared at 4 weeks of citrus SE. The most striking feature of our study was that five proteins were predicted to be involved in glutathione (GSH) metabolism and anti-oxidative stress, and they exhibited different expression patterns during SE. Based on that oxidative stress has been validated to enhance SE, the preferential representation for anti-oxidative proteins suggests that they could have a developmental role in citrus SE. Some proteins involved in cell division, photosynthesis and detoxification were also identified, and their possible roles in citrus SE were discussed. PMID:18989674

  10. 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 μM APM in liquid medium. However, the application of 25 μM in solid medium for 24 h produced the highest number of doubled haploid plants. Somatic regeneration from flower buds of haploid and mixoploid plants proved to be a successful approach for chromosome doubling, since diploid plants were obtained from the 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

  11. Jasmonic acid is a downstream component in the modulation of somatic embryogenesis by Arabidopsis Class 2 phytoglobin

    PubMed Central

    Mira, Mohamed M.; Wally, Owen S. D.; Elhiti, Mohamed; El-Shanshory, Adel; Reddy, Dhadi S.; Hill, Robert D.; Stasolla, Claudio

    2016-01-01

    Previous studies have shown that the beneficial effect of suppression of the Arabidopsis phytoglobin 2 gene, PGB2, on somatic embryogenesis occurs through the accumulation of nitric oxide (NO) within the embryogenic cells originating from the cultured explant. NO activates the expression of Allene oxide synthase (AOS) and Lipoxygenase 2 (LOX2), genes encoding two key enzymes of the jasmonic acid (JA) biosynthetic pathway, elevating JA content within the embryogenic tissue. The number of embryos in the single aos1-1 mutant and pgb2-aos1-1 double mutant declined, and was not rescued by increasing levels of NO stimulating embryogenesis in wild-type tissue. NO also influenced JA responses by up-regulating PLANT DEFENSIN 1 (PDF1) and JASMONATE-ZIM-PROTEIN (JAZ1), as well as down-regulating MYC2. The NO and JA modulation of MYC2 and JAZ1 controlled embryogenesis. Ectopic expression of JAZ1 or suppression of MYC2 promoted the formation of somatic embryos, while repression of JAZ1 and up-regulation of MYC2 reduced the embryogenic performance. Sustained expression of JAZ1 induced the transcription of several indole acetic acid (IAA) biosynthetic genes, resulting in higher IAA levels in the embryogenic cells. Collectively these data fit a model integrating JA in the PGB2 regulation of Arabidopsis embryogenesis. Suppression of PGB2 increases JA through NO. Elevated levels of JA repress MYC2 and induce JAZ1, favoring the accumulation of IAA in the explants and the subsequent production of somatic embryos. PMID:26962208

  12. 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

  13. Rorippa indica Regeneration via Somatic Embryogenesis Involving Frog Egg-like Bodies Efficiently Induced by the Synergy of Salt and Drought Stresses

    PubMed Central

    Xu, Kedong; Chang, Yunxia; Zhang, Yi; Liu, Kun; Zhang, Ju; Wang, Wei; Li, Zhanshuai; Wu, Jianxin; Ma, Shuya; Xin, Yuexing; Li, Chunjing; Zhou, Qianbei; Qiu, Hanhan; Pi, Yumei; Wang, Youwei; Tan, Guangxuan; Li, Chengwei

    2016-01-01

    Frog egg-like bodies (FELBs), novel somatic embryogenesis (SE) structures first observed in Solanum nigrum, were induced in Rorippa indica. NaCl-mediated salt and mannitol-mimicked drought stresses induced FELBs in R. indica, which is very different from the induction by plant growth regulators (PGRs) under low light condition that was used in S. nigrum FELB induction. It demonstrated that NaCl or mannitol supplements alone could induce FELBs in R. indica, but with low induction rates, while the synergy of NaCl and mannitol significantly increased the FELB induction rates. For the combination of 5.0 g/L mannitol and 10.0 g/L NaCl the highest FELB induction rate (100%) was achieved. It suggests that the synergy of drought and salt stresses can replace PGRs to induce FELBs in R. indica. On medium supplemented with 1.0 mg/L gibberellic acid all the inoculated in vitro FELBs developed into multiple plantlets. Morphological and histological analyses confirmed the identity of FELBs induced in R. indica and revealed that FELBs originate from root cortex cells. PMID:26796345

  14. Annotation of differentially expressed genes in the somatic embryogenesis of musa and their location in the banana genome.

    PubMed

    Maldonado-Borges, Josefina Ines; Ku-Cauich, José Roberto; Escobedo-Graciamedrano, Rosa Maria

    2013-01-01

    Analysis of cDNA-AFLP was used to study the genes expressed in zygotic and somatic embryogenesis of Musa acuminata Colla ssp. malaccensis, and a comparison was made between their differential transcribed fragments (TDFs) and the sequenced genome of the double haploid- (DH-) Pahang of the malaccensis subspecies that is available in the network. A total of 253 transcript-derived fragments (TDFs) were detected with apparent size of 100-4000 bp using 5 pairs of AFLP primers, of which 21 were differentially expressed during the different stages of banana embryogenesis; 15 of the sequences have matched DH-Pahang chromosomes, with 7 of them being homologous to gene sequences encoding either known or putative protein domains of higher plants. Four TDF sequences were located in all Musa chromosomes, while the rest were located in one or two chromosomes. Their putative individual function is briefly reviewed based on published information, and the potential roles of these genes in embryo development are discussed. Thus the availability of the genome of Musa and the information of TDFs sequences presented here opens new possibilities for an in-depth study of the molecular and biochemical research of zygotic and somatic embryogenesis of Musa. PMID:24027442

  15. Alterations in the transcriptome of soybean in response to enhanced somatic embryogenesis promoted by orthologs of Agamous-like15 and Agamous-like18.

    PubMed

    Zheng, Qiaolin; Perry, Sharyn E

    2014-03-01

    Somatic embryogenesis (SE) is a poorly understood process during which competent cells respond to inducing conditions, allowing the development of somatic embryos. It is important for the regeneration of transgenic plants, including for soybean (Glycine max). We report here that constitutive expression of soybean orthologs of the Arabidopsis (Arabidopsis thaliana) MADS box genes Agamous-like15 (GmAGL15) and GmAGL18 increased embryogenic competence of explants from these transgenic soybean plants. To understand how GmAGL15 promotes SE, expression studies were performed. Particular genes of interest involved in embryogenesis (abscisic acid-insensitive3 and FUSCA3) were found to be directly up-regulated by GmAGL15 by using a combination of quantitative reverse transcription-polymerase chain reaction and chromatin immunoprecipitation. To look more broadly at changes in gene expression in response to GmAGL15, we assessed the transcriptome using the Affymetrix Soybean Genome Array. Interestingly, the gene expression profile of 35Spro:GmAGL15 explants (0 d in culture) was found to resemble nontransgenic tissue that had been induced for SE by being placed on induction medium for 3 d, possibly explaining the more rapid SE development observed on 35Spro:GmAGL15 tissue. In particular, transcripts from genes related to the stress response showed increased transcript accumulation in explants from 35Spro:GmAGL15 tissue. These same genes also showed increased transcript accumulation in response to culturing nontransgenic soybean explants on the medium used to induce SE. Overexpression of GmAGL15 may enhance SE by making the tissue more competent to respond to 2,4-dichlorophenoxyacetic acid induction by differential regulation of genes such as those involved in the stress response, resulting in more rapid and prolific SE. PMID:24481137

  16. Thidiazuron induces shoot organogenesis at low concentrations and somatic embryogenesis at high concentrations on leaf and petiole explants of African violet (Saintpaulia ionantha Wendl).

    PubMed

    Mithila, J; Hall, J C; Victor, J M R; Saxena, P K

    2003-01-01

    Regeneration via shoot organogenesis and somatic embryogenesis was observed from thidiazuron (TDZ)-treated leaf and petiole explants of greenhouse- and in vitro-grown African violet plants. The response of cultures to other growth regulators over a range of 0.5 microM to 10 microM was 50% less than that observed with TDZ. A comparative study among several cultivars of African violet indicated that "Benjamin" and "William" had the highest regeneration potential. In "Benjamin", higher frequencies of shoot organogenesis (twofold) and somatic embryogenesis (a 50% increase) were observed from in vitro- and greenhouse-grown plants, respectively. At concentrations lower than 2.5 microM, TDZ induced shoot organogenesis, whereas at higher doses (5-10 microM) somatic embryos were formed. These findings provide the first report of simultaneous shoot organogenesis and somatic embryogenesis of African violet explants in response to TDZ. PMID:12789442

  17. 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

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

    PubMed

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

    2010-11-01

    Of the various alternatives for cloning elite conifers, somatic embryogenesis (SE) appears to be the best option. In recent years, significant areas of lodgepole pine (Pinus contorta) forest have been devastated by the mountain pine beetle (MPB) in Western Canada. In an attempt to establish an SE propagation system for MPB-resistant lodgepole pine, several families displaying varying levels of resistance were selected for experimentation involving shoot bud and immature seed explants. In bud cultures, eight embryogenic lines were induced from 2 of 15 genotypes following various treatments. Genotype had an important influence on embryogenic culture initiation, and this effect was consistent over time. These lines were identified by microscopic observation and genetic markers. Despite the abundance of early somatic embryos, the cultures have yet to develop into mature embryos. In contrast, immature zygotic embryos (ZEs) cultured from megagametophytes initiated SE at an early dominance stage via nodule-type callus in 1 of 10 genotypes. As part of the study, putative embryogenesis-specific genes, WOX2 (WUSCHELL homeobox 2) and HAP3A, were analyzed in cultures of both shoot bud explants and ZEs. On the basis of these analyses, we postulate that PcHAP3A was expressed mainly in callus and may be involved in cell division, whereas WOX2 was expressed mainly in embryonal mass (EM)-like tissues. The findings from this study, based on molecular assessment, suggest that the cell lines derived from bud cultures were truly EM. Moreover, these experimental observations suggest that PcWOX2 could be used as an early genetic marker to discriminate embryogenic cultures from callus. PMID:20935320

  19. Developmental and hormonal regulation of direct shoot organogenesis and somatic embryogenesis in sugarcane (Saccharum spp. interspecific hybrids) leaf culture.

    PubMed

    Lakshmanan, Prakash; Geijskes, R Jason; Wang, Lifang; Elliott, Adrian; Grof, Christopher P L; Berding, Nils; Smith, Grant R

    2006-10-01

    Rapid and efficient in vitro regeneration methods that minimise somaclonal variation are critical for the genetic transformation and mass propagation of commercial varieties. Using a transverse thin cell layer culture system, we have identified some of the developmental and physiological constraints that limit high-frequency regeneration in sugarcane leaf tissue. Tissue polarity and consequently the orientation of the explant in culture, size and developmental phase of explant, and auxin concentration play a significant role in determining the organogenic potential of leaf tissue in culture. Both adventitious shoot production and somatic embryogenesis occurred on the proximal cut surface of the explant, and a regeneration gradient, decreasing gradually from the basal to the distal end, exists in the leaf roll. Importantly, auxin, when added to the culture medium, reduced this spatial developmental constraint, as well as the effect of genotype on plant regeneration. Transverse sections (1-2 mm thick) obtained from young leaf spindle rolls and orienting explants with its distal end facing the medium (directly in contact with medium) are critical for maximum regeneration. Shoot regeneration was observed as early as 3 weeks on MS medium supplemented with alpha-naphthalenencetic acid (NAA) and 6-benzyladenine, while somatic embryogenesis or both adventitious shoot organogenesis and somatic embryogenesis occurred on medium with NAA and chlorophenoxyacetic acid. Twenty shoots or more could be generated from a single transverse section explant. These shoots regenerated roots and successfully established after transplanted to pots. Large numbers of plantlets can be regenerated directly and rapidly using this system. SmartSett, the registered name for this process and the plants produced, will have significant practical applications for the mass propagation of new cultivars and in genetic modification programs. The SmartSett system has already been used commercially to

  20. Isolation of putative glycoprotein gene from early somatic embryo of carrot and its possible involvement in somatic embryo development.

    PubMed

    Takahata, Kiminori; Takeuchi, Miyuki; Fujita, Minoru; Azuma, Junichi; Kamada, Hiroshi; Sato, Fumihiko

    2004-11-01

    Somatic embryogenesis is a unique process in plant cells. For example, embryogenic cells (EC) of carrot (Daucus carota) maintained in a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) regenerate whole plants via somatic embryogenesis after the depletion of 2,4-D. Although some genes such as C-ABI3 and C-LEC1 have been found to be involved in somatic embryogenesis, the critical molecular and cellular mechanisms for somatic embryogenesis are unknown. To characterize the early mechanism in the induction of somatic embryogenesis, we isolated genes expressed during the early stage of somatic embryogenesis after 2,4-D depletion. Subtractive hybridization screening and subsequent RNA gel blot analysis suggested a candidate gene, Carrot Early Somatic Embryogenesis 1 (C-ESE1). C-ESE1 encodes a protein that has agglutinin and S-locus-glycoprotein domains and its expression is highly specific to primordial cells of somatic embryo. Transgenic carrot cells with reduced expression of C-ESE1 had wide intercellular space and decreased polysaccharides on the cell surface and showed delayed development in somatic embryogenesis. The importance of cell-to-cell attachment in somatic embryogenesis is discussed. PMID:15574842

  1. New Insights into Somatic Embryogenesis: LEAFY COTYLEDON1, BABY BOOM1 and WUSCHEL-RELATED HOMEOBOX4 Are Epigenetically Regulated in Coffea canephora

    PubMed Central

    Nic-Can, Geovanny I.; López-Torres, Adolfo; Barredo-Pool, Felipe; Wrobel, Kazimierz; Loyola-Vargas, Víctor M.; Rojas-Herrera, Rafael; De-la-Peña, Clelia

    2013-01-01

    Plant cells have the capacity to generate a new plant without egg fertilization by a process known as somatic embryogenesis (SE), in which differentiated somatic cells can form somatic embryos able to generate a functional plant. Although there have been advances in understanding the genetic basis of SE, the epigenetic mechanism that regulates this process is still unknown. Here, we show that the embryogenic development of Coffea canephora proceeds through a crosstalk between DNA methylation and histone modifications during the earliest embryogenic stages of SE. We found that low levels of DNA methylation, histone H3 lysine 9 dimethylation (H3K9me2) and H3K27me3 change according to embryo development. Moreover, the expression of LEAFY COTYLEDON1 (LEC1) and BABY BOOM1 (BBM1) are only observed after SE induction, whereas WUSCHEL-RELATED HOMEOBOX4 (WOX4) decreases its expression during embryo maturation. Using a pharmacological approach, it was found that 5-Azacytidine strongly inhibits the embryogenic response by decreasing both DNA methylation and gene expression of LEC1 and BBM1. Therefore, in order to know whether these genes were epigenetically regulated, we used Chromatin Immunoprecipitation (ChIP) assays. It was found that WOX4 is regulated by the repressive mark H3K9me2, while LEC1 and BBM1 are epigenetically regulated by H3K27me3. We conclude that epigenetic regulation plays an important role during somatic embryogenic development, and a molecular mechanism for SE is proposed. PMID:23977240

  2. In vitro regeneration through organogenesis and somatic embryogenesis in pigeon pea [ Cajanus cajan (L.) Millsp.] cv. JKR105.

    PubMed

    Krishna, Gaurav; Reddy, P Sairam; Ramteke, Pramod W; Rambabu, Pogiri; Sohrab, Sayed S; Rana, Debashis; Bhattacharya, Parthasarathi

    2011-10-01

    In vitro regeneration of pigeon pea through organogenesis and somatic embryogenesis was demonstrated with pigeon pea cv. JKR105. Embryonic axes explants of pigeon pea showed greater regeneration of shoot buds on 2.5 mg L(-1) 6-benzylaminopurine (BAP) in the medium, followed by further elongation at lower concentrations. Rooting of shoots was observed on half-strength Murashige and Skoog (MS) medium with 2 % sucrose and 0.5 mg L(-1) 3-indolebutyric acid (IBA). On the other hand, the regeneration of globular embryos from cotyledon explant was faster and greater with thidiazuron (TDZ) than BAP with sucrose as carbohydrate source. These globular embryos were maturated on MS medium with abscisic acid (ABA) and finally germinated on half-strength MS medium at lower concentrations of BAP. Comparison of regeneration pathways in pigeon pea cv. JKR105 showed that the turnover of successful establishment of plants achieved through organogenesis was more compared to somatic embryogenesis, despite the production of more embryos than shoot buds. PMID:23573031

  3. 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

  4. High efficient somatic embryogenesis development from leaf cultures of Citrullus colocynthis (L.) Schrad for generating true type clones.

    PubMed

    Ramakrishna, D; Shasthree, T

    2016-04-01

    We report an efficient somatic embryogenesis and plant regeneration system using leaf cultures of Citrullus colocynthis (L.) and assessed the effect of plant growth regulators on the regeneration process. Initially leaf explants were cultured on Murashige and Skoog medium supplemented with different concentrations of auxins viz., 2,4-dichlorophenoxyacetic acid, 1-naphthaleneacetic acid, gibberellic acid alone and along with combination of 6-benzylaminopurine. The different forms of calli such as compact, white friable, creamy friable, brownish nodular, green globular and green calli were induced from the leaf explants on MS medium containing different concentrations of auxins and gibberellins. Subsequently initial callus was subcultured at 1.5 mg L(-1) BAP + 1.0 mg L(-1) 2,4-D which resulted in 25 % somatic embryos from 85 % nodular embryogenic nodular callus that is highest percentage. Similarly the lowest percentage of somatic embryos was recorded at 2.5 mg L(-1) BAP + 0.5 mg L(-1) NAA from 55 % embryogenic globular callus i.e., 16 %. High frequency of embryo development takes place at intermittent light when compared with continuous light in the individual subcultures. The cotyledonary embryos were developed into complete platelets on MS medium. In vitro regenerated plantlets were washed to remove the traces of agar and then transferred to sterile vermiculite and sand (2:1) containing pot. PMID:27436919

  5. 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

  6. Stress-related function of bHLH109 in somatic embryo induction in Arabidopsis.

    PubMed

    Nowak, Katarzyna; Gaj, Małgorzata D

    2016-04-01

    The bHLH109 gene of the bHLH family was identified among the transcription factor encoding genes that were differentially expressed in an embryogenic culture of Arabidopsis. A strong activation of bHLH109 expression was found to be associated with somatic embryogenesis (SE) induction. Several pieces of evidence suggested the involvement of bHLH109 in SE, including the high stimulation of the gene expression in SE-induced explants, which contrasts to the drastically lower level of the gene transcripts in the non-embryogenic callus and in tissue that is induced towards shoot regeneration via organogenesis. Moreover, in contrast to the overexpression of bHLH109, which has been indicated to enhance SE induction in a culture, the bhlh109 knock-out mutation was found to impair the embryogenic potential of explants. In order to identify the genes interacting with the bHLH109, the candidate co-expressed genes were identified in a yeast one hybrid assay. The in vitro regulatory interactions that were identified were verified through mutant and expression analysis. The results suggest that in SE bHLH109 acts as an activator of ECP63, a member of the LEA (LATE EMBRYOGENESIS ABUNDANT) family. Among the potential regulators of bHLH109, three candidates (At5g61620, bZIP4 and bZIP43) were indicated to possibly control bHLH109. The functions of all of the genes that are assumed to interact with bHLH109 are annotated to stress responses. Collectively, the results of the study provide new evidence that cell responses to stress that is imposed under in vitro conditions underlies the promotion of SE. bHLH109 may play a central role in the stress-related mechanism of SE induction via an increased accumulation of the LEA protein (ECP63), which results in the enhanced tolerance of the cells to stress. PMID:26973252

  7. 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

  8. Characterization of VvSERK1, VvSERK2, VvSERK3 and VvL1L genes and their expression during somatic embryogenesis of grapevine (Vitis vinifera L.).

    PubMed

    Schellenbaum, Paul; Jacques, Alban; Maillot, Pascale; Bertsch, Christophe; Mazet, Flore; Farine, Sibylle; Walter, Bernard

    2008-12-01

    Little is known about the genes expressed during grapevine somatic embryogenesis. Both groups of Somatic Embryogenesis Receptor Kinase (SERK) and Leafy Cotyledon (LEC and L1L) genes seem to play key roles during somatic embryogenesis in various plant species. Therefore, we identified and analysed the sequences of VvSERK and VvL1L (Leafy cotyledon1-Like) genes. The deduced amino acid sequences of VvSERK1, VvSERK2 and VvSERK3 are very similar to that of registered SERK proteins, with highest homologies for the kinase domain in the C-terminal region. The amino acid sequence of VvL1L presents all the domains that are characteristic for LEC1 and L1L proteins, particularly, the 16 amino acid residues that serve as signature of the B-domain. Phylogenetic analysis distinguishes members of subclass LEC1 and subclass L1L, and VvL1L is closely related to L1L proteins. Using semi-quantitative RT-PCR, we studied gene expression of VvSERK1, VvSERK2, VvSERK3 and VvL1L in calli and somatic embryos obtained from anther culture of Vitis vinifera L. cv Chardonnay. Expression of VvSERK2 is relatively stable during in vitro culture. In contrast, VvSERK1, VvSERK3 and VvL1L are expressed more 4 to 6 weeks after transfer of the calli onto embryo induction medium, before the visible appearance of embryos on the calli as seen by environmental scanning electron microscopy. Later on (8 weeks after transfer) VvSERK1 expression is maintained in the embryogenic calli and VvSERK3 in the embryos, whereas VvL1L expression is very low. All together, these data suggest the involvement of VvSERK and VvL1L genes in grapevine somatic embryogenesis. PMID:18766346

  9. Selective autophagic degradation of maternally-loaded germline P granule components in somatic cells during C. elegans embryogenesis.

    PubMed

    Zhao, Yu; Tian, E; Zhang, Hong

    2009-07-01

    Germline P granules are specialized protein/RNA aggregates that are found exclusively in germ cells in C. elegans. During the early embryonic divisions that generate germ blastomeres, aggregate-prone P granule components PGL-1 and PGL-3 that remain in the cytoplasm destined for somatic daughters are selectively removed by autophagy. Loss-of-function of components of the autophagy pathway, including the VPS-34/BEC-1 complex, causes accumulation of PGL-1 and PGL-3 into aggregates in somatic cells (termed PGL granules). Formation of PGL granules depends on SEPA-1, which is an integral component of these granules. SEPA-1 is preferentially degraded by autophagy and is also required for the autophagic degradation of PGL-1 and PGL-3. SEPA-1 functions as a bridging molecule in mediating degradation of P granule components by directly interacting with PGL-3 and also with the autophagy protein LGG-1/Atg8. The defect in embryonic development in autophagy mutants is suppressed by mutation of sepa-1, suggesting that autophagic degradation of PGL granule components may provide nutrients for embryogenesis and/or also prevent the formation of aggregates that could be toxic for animal development. Our study reveals a specific physiological function of selective autophagic degradation during C. elegans development. PMID:19372764

  10. Plant regeneration via somatic embryogenesis in the seeded diploid banana Musa ornata Roxb.

    PubMed

    Cronauer-Mitra, S S; Krikorian, A D

    1988-01-01

    Somatic embryos of a seeded diploid ornamental banana (Musa ornata Roxb.) were obtained from zygotic embryos cultured on semi-solid Murashige and Skoog (MS) (1962) medium with the auxin 2,4-D (0.5, 1, 2 mg/l) and 5% CW. Removal of 2,4-D and transferral to Schenk and Hildebrandt (SH) (1972) salts with CW followed by basal MS led to embryo germination and growth. Plantlet production was obtained using filter paper bridges in liquid half-strength SH medium with 1% sucrose. The remarkable phenotypic fidelity of somatic embryos to that of zygotic embryos and the presence of a haustorium-like outgrowth on the somatic embryos is described. PMID:11538845

  11. Cellular and molecular changes associated with competence acquisition during passion fruit somatic embryogenesis: ultrastructural characterization and analysis of SERK gene expression.

    PubMed

    Rocha, Diego Ismael; Pinto, Daniela Lopes Paim; Vieira, Lorena Melo; Tanaka, Francisco André Ossamu; Dornelas, Marcelo Carnier; Otoni, Wagner Campos

    2016-03-01

    The integration of cellular and molecular data is essential for understanding the mechanisms involved in the acquisition of competence by plant somatic cells and the cytological changes that underlie this process. In the present study, we investigated the dynamics and fate of Passiflora edulis Sims cotyledon explants that were committed to somatic embryogenesis by characterizing the associated ultrastructural events and analysing the expression of a putative P. edulis ortholog of the Somatic Embryogenesis Receptor-like Kinase (SERK) gene. Embryogenic calli were obtained from zygotic embryo explants cultured on Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid and 6-benzyladenine. Callus formation was initiated by the division of cells derived from the protodermal and subprotodermal cells on the abaxial side of the cotyledons. The isodiametric protodermal cells of the cotyledon explants adopted a columnar shape and became meristematic at the onset of PeSERK expression, which was not initially detected in explant cells. Therefore, we propose that these changes represent the first observable steps towards the acquisition of a competent state within this regeneration system. PeSERK expression was limited to the early stages of somatic embryogenesis; the expression of this gene was confined to proembryogenic zones and was absent in the embryos after the globular stage. Our data also demonstrated that the dynamics of the mobilization of reserve compounds correlated with the differentiation of the embryogenic callus. PMID:26008651

  12. Somatic and movement inductions phantom limb in non-amputees

    NASA Astrophysics Data System (ADS)

    Casas, D. M.; Gentiletti, G. G.; Braidot, A. A.

    2016-04-01

    The illusion of the mirror box is a tool for phantom limb pain treatment; this article proposes the induction of phantom limb syndrome on non-amputees upper limb, with a neurological trick of the mirror box. With two study situations: a) Somatic Induction is a test of the literature reports qualitatively, and novel proposal b) Motor Induction, which is an objective report by recording surface EEG. There are 3 cases proposed for Motor illusion, for which grasped movement is used: 1) Control: movement is made, 2) illusion: the mirror box is used, and 3) Imagination: no movement is executed; the subject only imagines its execution. Three different tasks are registered for each one of them (left hand, right hand, and both of them). In 64% of the subjects for somatic experience, a clear response to the illusion was observed. In the experience of motor illusion, cortical activation is detected in both hemispheres of the primary motor cortex during the illusion, where the hidden hand remains motionless. These preliminary findings in phantom limb on non-amputees can be a tool for neuro-rehabilitation and neuro-prosthesis control training.

  13. High expression of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE coincides with initiation of various developmental pathways in in vitro culture of Trifolium nigrescens.

    PubMed

    Pilarska, Maria; Malec, Przemysław; Salaj, Jan; Bartnicki, Filip; Konieczny, Robert

    2016-03-01

    The aim of this study was to identify and examine the expression pattern of the ortholog of SOMATIC EMBRYOGENESIS RECEPTOR-LIKE KINASE gene from Trifolium nigrescens (TnSERK) in embryogenic and non-regenerative cultures of immature cotyledonary-stage zygotic embryos (CsZEs). In the presence of 1-naphthaleneacetic acid and N(6)-[2-isopentenyl]-adenine, the CsZE regenerated embryoids directly and in a lengthy culture produced callus which was embryogenic or remained non-regenerative. As revealed by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR), the TnSERK was expressed in both embryogenic and non-regenerative cultures, but the expression level was significantly higher in embryogenic ones. An in situ RNA hybridization assay revealed that the expression of TnSERK preceded the induction of cell division in explants, and then, it was maintained exclusively in actively dividing cells from which embryoids, embryo-like structures (ELSs), callus or tracheary elements were produced. However, the cells involved in different morphogenic events differed in intensity of hybridization signal which was the highest in embryogenic cells. The TnSERK was up-regulated during the development of embryoids, but in cotyledonary embryos, it was preferentially expressed in the regions of the apical meristems. The occurrence of morphological and anatomical abnormalities in embryoid development was preceded by a decline in TnSERK expression, and this coincided with the parenchymatization of the ground tissue in developing ELSs. TnSERK was also down-regulated during the maturation of parenchyma and xylem elements in CsZE and callus. Altogether, these data suggest the involvement of TnSERK in the induction of various developmental programs related to differentiation/transdifferentiation and totipotent state of cell(s). PMID:25876517

  14. Partial characterization of genes whose transcripts accumulate preferentially in cell clusters at the earliest stage of carrot somatic embryogenesis.

    PubMed

    Yasuda, H; Nakajima, M; Ito, T; Ohwada, T; Masuda, H

    2001-04-01

    We attempted to identify genes that are preferentially expressed immediately after somatic cells divide to form cell clusters at the earliest stage of carrot somatic embryogenesis when they are not or barely expressed in non-embryogenic suspension-cultured cells in the presence of 2,4-D. Using the differential display technique, we isolated three cDNA clones, designated No. 43, No. 87 and No. 93. The No. 43 transcript was preferentially expressed in the earliest cell clusters, its level decreased drastically at the globular and heart-shaped and torpedo-shaped stages, and it was not detected in non-embryogenic suspension-cultured cells. No. 43 cDNA encoded a protein with homology to thaumatin-like proteins and the deduced positions of seven cysteine residues in the 63 amino acid sequence from the carboxyl terminus were identical to those in thaumatin-like proteins. The full-length nucleotide sequence of No. 93 cDNA was determined and its product was about 80% homologous to precursor of the 14 kDa proline-rich DC 2.15 protein of carrot at the amino acid level. However, the deduced amino acid sequence lacked the characteristic core of repeating Pro-X motifs found in DC 2.15. The No. 93 transcript accumulated preferentially in the earliest cell clusters but it was also detected at a low level in non-embryogenic suspension-cultured cells, unlike DC 2.15 transcripts that begin to accumulate in heart-shaped embryos before their level falls in torpedo-shaped embryos. No. 87 transcripts were expressed preferentially in the earliest cell clusters that has been incubated with 2,4-D but were also detected at a low level in suspension-cultured cells subcultured in the continued presence of 2,4-D. The No. 87 cDNA exhibited no significant homology to any sequences in databases. PMID:11430432

  15. Somatic embryogenesis and plant regeneration in tissue cultures of radish (Raphanus sativus L.).

    PubMed

    Jeong, W J; Min, S R; Liu, J R

    1995-07-01

    Hypocotyl segments of 2- to 3-week-old radish (Raphanus sativus L. cv. F1 Handsome Fall) seedlings produced yellowish compact calli when cultured on Murashige and Skoog's (MS) medium supplemented with 1 mgl(-1) 2,4-dichlorophenoxyacetic acid (2,4-D). Upon transfer onto medium containing 6-benzyladenine and α-naphthaleneacetic acid, up to 5.3% of the calli gave rise to a few somatic embryos. When subcultured for 3 to 6 months, 7% of the yellowish, compact calli produced white, compact calli which formed numerous embryos. These calli maintained their embryogenic capacity for over 18 months. When cultured on medium containing 0.1 to 3 mgl(-1) 2,4-D, up to 90% of longitudinally sliced somatic embryo halves produced calli with numerous secondary embryos. Embryos were transferred onto medium containing 0.1 mgl(-1) 2,4-D and 1 mgl(-1) abscisic acid where they developed into the cotyledonary stage. Upon transfer onto half-strength MS basal medium, approximately 90% of the embryos developed into plantlets. These plantlets were successfully transplanted in potting soil and after cold treatment they were grown to maturity in a phytotron. PMID:24194314

  16. Pretreatments, conditioned medium and co-culture increase the incidence of somatic embryogenesis of different Cichorium species

    PubMed Central

    Couillerot, Jean-Paul; Windels, David; Vazquez, Franck; Michalski, Jean-Claude; Hilbert, Jean-Louis; Blervacq, Anne-Sophie

    2012-01-01

    Somatic embryogenesis (SE) in Cichorium involves dedifferentiation and redifferentiation of single cells and can be induced by specific in vitro culture conditions. We have tested the effect of various treatments on the incidence of SE (ISE) of an interspecific embryogenic hybrid (C. endivia x C. intybus) and of different commercial chicories (C. endivia and C. intybus) that are typically recalcitrant to SE in standard culture conditions. We found that the ISE of the hybrid is significantly increased by pretreatment of tissues by submersion in solutions of glycerol, abscisic acid, spermine, putrescine or of combinations of these compounds. Interestingly, the most efficient of these pretreatments also had an unexpectedly high effect on the ISE of the C. intybus cultivars. The ISE of the hybrid and of the commercial chicories were increased when explants were co-cultured with highly embryogenic chicory explants or when they were cultured in conditioned medium. These observations established that unidentified SE-promoting factors are released in the culture medium. HPLC analyses of secreted Arabino-Galactan Proteins (AGPs), which are known to stimulate SE, did not allow identifying a fraction containing differentially abundant AGP candidates. However, pointing to their role in promoting SE, we found that the hybrid had a drastically higher ISE when amino sugars and L-Proline, the putative precursors of secreted AGPs, were both added to the medium. PMID:22301978

  17. Evolution of endogenous hormone concentration in embryogenic cultures of carrot during early expression of somatic embryogenesis.

    PubMed

    Jiménez, V M; Guevara, E; Herrera, J; Bangerth, F

    2005-01-01

    Embryogenic callus and suspension cultures of carrot (Daucus carota L., cv. Nantaise), growing on/in medium including 1 mg/l 2,4-dichlorophenoxy acetic acid (2,4-D), were transferred to medium with or without this plant growth regulator, to impair or induce, respectively, further development of somatic embryos. The endogenous hormone levels of the cultures were determined over 7 days by means of radio-immunoassay, to characterize their evolution in the initial stages of embryo development. In general, levels of indoleacetic acid (IAA) and abscisic acid (ABA) showed only short-lived differences among treatments during this time in both types of tissue analyzed (i.e., a peak of IAA in callus cultures in the absence of 2,4-D, 48 h after medium change, and higher ABA contents 144 h after subculture of suspension cultures in the presence of 2,4-D). Gibberellins (1, 3 and 20) were detected only in suspension cultures devoid of 2,4-D, starting 24 h after subculture. Concerning the evaluated cytokinins-zeatin/zeatin riboside and N6(Delta2-isopentenyl) adenine/N6(Delta2-isopentenyl) adenosine-the most remarkable observation is that high levels of the former generally coincided with low concentrations of the latter, indicating a shift from precursor to the active form, and vice versa. PMID:15375630

  18. 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

  19. Somatic embryogenesis, pigment accumulation, and synthetic seed production in Digitalis davisiana Heywood.

    PubMed

    Verma, Sandeep Kumar; Sahin, Gunce; Gurel, Ekrem

    2016-04-01

    Digitalis davisiana, commonly called Alanya foxglove, from Turkey, is an important medicinal herb as the main source of cardiac glycosides, cardenolides, anthraquinones, etc. It is also known in the Indian Medicine for treatment of wounds and burns. It has ornamental value as well. Overexploitation of D. davisiana has led this species to be declared protected, and thereby encouraged various methods for its propagation. In this study, an optimized and efficient plant tissue culture protocol was established using cotyledonary leaf, hypocotyl and root explants of D. davisiana. Callus tissues were obtained from the cotyledonary leaf, hypocotyl and root segments cultured on Murashige and Skoog's (MS) medium containing different plant growth regulators. The maximum number of somatic embryos were achieved by the MS medium containing 6-benzyladenine (1.0 mg/L BAP) or 2,4-dichlorophenoxy acetic acids (0.1 mg/L 2,4-D), which produced an average of 8.3 ± 1.5 or 5.3 ± 1.5 embryos per cotyledonary leaf, respectively. After 3 wk of culture in MS medium supplemented with 1.0 mg/L 2,4-D, callus showed a clear accumulation of orange pigmentation. Shoot regeneration was remarkably higher (14.3 indirect shoots) in a combination of α-naphthalene acetic acid (0.25 mg/L NAA) plus 3.0 mg/L BAP than 2.0 mg/L zeatin (10.3 ± 0.5 direct shoots) alone. The shoots were successfully rooted on MS medium supplemented with NAA (0.1-1.0 mg/L). In addition, synthetic seeds were produced by encapsulating shoot tips in 4% sodium alginate solution. Maximum conversion frequency of 76.6% was noted from encapsulated shoot tips cultured on 0.25 mg/L NAA with 1.0 mg/L BAP. The encapsulated shoot tips could be stored up to 60 days at 4 °C. Regenerated plantlets of D. davisiana were successfully acclimatized and transferred to soil. This study has demonstrated successful preservation of elite genotypes of D. davisiana. PMID:27295921

  20. Alterations in the Transcriptome of Soybean in Response to Enhanced Somatic Embryogenesis Promoted by Orthologs of AGAMOUS-Like15 and AGAMOUS-Like181[C][W][OPEN

    PubMed Central

    Zheng, Qiaolin; Perry, Sharyn E.

    2014-01-01

    Somatic embryogenesis (SE) is a poorly understood process during which competent cells respond to inducing conditions, allowing the development of somatic embryos. It is important for the regeneration of transgenic plants, including for soybean (Glycine max). We report here that constitutive expression of soybean orthologs of the Arabidopsis (Arabidopsis thaliana) MADS box genes AGAMOUS-Like15 (GmAGL15) and GmAGL18 increased embryogenic competence of explants from these transgenic soybean plants. To understand how GmAGL15 promotes SE, expression studies were performed. Particular genes of interest involved in embryogenesis (ABSCISIC ACID-INSENSITIVE3 and FUSCA3) were found to be directly up-regulated by GmAGL15 by using a combination of quantitative reverse transcription-polymerase chain reaction and chromatin immunoprecipitation. To look more broadly at changes in gene expression in response to GmAGL15, we assessed the transcriptome using the Affymetrix Soybean Genome Array. Interestingly, the gene expression profile of 35Spro:GmAGL15 explants (0 d in culture) was found to resemble nontransgenic tissue that had been induced for SE by being placed on induction medium for 3 d, possibly explaining the more rapid SE development observed on 35Spro:GmAGL15 tissue. In particular, transcripts from genes related to the stress response showed increased transcript accumulation in explants from 35Spro:GmAGL15 tissue. These same genes also showed increased transcript accumulation in response to culturing nontransgenic soybean explants on the medium used to induce SE. Overexpression of GmAGL15 may enhance SE by making the tissue more competent to respond to 2,4-dichlorophenoxyacetic acid induction by differential regulation of genes such as those involved in the stress response, resulting in more rapid and prolific SE. PMID:24481137

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

    PubMed

    Wójcikowska, Barbara; Jaskóła, Karolina; Gąsiorek, Przemysław; Meus, Magdalena; Nowak, Katarzyna; Gaj, Małgorzata 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

  2. 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

  3. Hormonally regulated overexpression of Arabidopsis WUS and conifer LEC1 (CHAP3A) in transgenic white spruce: implications for somatic embryo development and somatic seedling growth.

    PubMed

    Klimaszewska, Krystyna; Pelletier, Gervais; Overton, Catherine; Stewart, Don; Rutledge, Robert G

    2010-07-01

    Adult conifers are still recalcitrant in clonal propagation despite significant advances in forest tree biotechnology. Plant regeneration through somatic embryogenesis from explants older than mature zygotic embryos is either difficult or impossible to achieve. To investigate if ectopic expression of transcription factors involved in the induction of the embryogenic process would induce somatic embryogenesis in Picea glauca (white spruce) somatic plants, we used the LEAFY-COTYLEDON1 homolog cloned from Picea mariana, CHAP3A, and Arabidopsis thaliana WUS to transform embryonal mass of P. glauca. Ectopic gene expression was induced by 17-beta-estradiol during stages of somatic embryogenesis (early embryogenesis and late embryogenesis) and somatic seedling growth in the transgenics. Of the two transcription factors, only WUS produced severe phenotypes by disrupting the development of somatic embryos on the maturation medium and inhibiting germination. However, none of the transgenes induced ectopic somatic embryogenesis even in the presence of plant growth regulators. Absolute quantitative PCR confirmed the expression of both CHAP3A and WUS in transgenic embryonal mass and in all parts of somatic seedlings. A high expression of the transgenes did not influence expression profiles of any of the ten other transcription factors tested, some of which have been known to be involved in the process of embryogenesis. Implications of these results for further work are discussed. PMID:20424847

  4. Abscisic acid and stress treatment are essential for the acquisition of embryogenic competence by carrot somatic cells.

    PubMed

    Kikuchi, Akira; Sanuki, Nobuya; Higashi, Katsumi; Koshiba, Tomokazu; Kamada, Hiroshi

    2006-03-01

    Studies of carrot embryogenesis have suggested that abscisic acid (ABA) is involved in somatic embryogenesis. A relationship between endogenous ABA and the induction of somatic embryogenesis was demonstrated using stress-induced system of somatic embryos. The embryonic-specific genes C-ABI3 and embryogenic cell proteins (ECPs) were expressed during stress treatment prior to the formation of somatic embryos. The stress-induction system for embryogenesis was clearly distinguished by two phases: the acquisition of embryogenic competence and the formation of a somatic embryo. Somatic embryo formation was inhibited by the application of fluridone (especially at 10(-4) M), a potent inhibitor of ABA biosynthesis, during stress treatment. The inhibitory effect of fluridone was nullified by the simultaneous application of fluridone and ABA. The level of endogenous ABA increased transiently during stress. However, somatic embryogenesis was not significantly induced by the application of only ABA to the endogenous level, in the absence of stress. These results suggest that the induction of somatic embryogenesis, in particular the acquisition of embryogenic competence, is caused not only by the presence of ABA but also by physiological responses that are directly controlled by stresses. PMID:16160844

  5. Effect of Cryopreservation and Post-Cryopreservation Somatic Embryogenesis on the Epigenetic Fidelity of Cocoa (Theobroma cacao L.)

    PubMed Central

    Adu-Gyamfi, Raphael; Wetten, Andy; Marcelino Rodríguez López, Carlos

    2016-01-01

    While cocoa plants regenerated from cryopreserved somatic embryos can demonstrate high levels of phenotypic variability, little is known about the sources of the observed variability. Previous studies have shown that the encapsulation-dehydration cryopreservation methodology imposes no significant extra mutational load since embryos carrying high levels of genetic variability are selected against during protracted culture. Also, the use of secondary rather than primary somatic embryos has been shown to further reduce the incidence of genetic somaclonal variation. Here, the effect of in vitro conservation, cryopreservation and post-cryopreservation generation of somatic embryos on the appearance of epigenetic somaclonal variation were comparatively assessed. To achieve this we compared the epigenetic profiles, generated using Methylation Sensitive Amplified Polymorphisms, of leaves collected from the ortet tree and from cocoa somatic embryos derived from three in vitro conditions: somatic embryos, somatic embryos cryopreserved in liquid nitrogen and somatic embryos generated from cryoproserved somatic embryos. Somatic embryos accumulated epigenetic changes but these were less extensive than in those regenerated after storage in LN. Furthermore, the passage of cryopreserved embryos through another embryogenic stage led to further increase in variation. Interestingly, this detected variability appears to be in some measure reversible. The outcome of this study indicates that the cryopreservation induced phenotypic variability could be, at least partially, due to DNA methylation changes. Key message: Phenotypic variability observed in cryostored cocoa somatic-embryos is epigenetic in nature. This variability is partially reversible, not stochastic in nature but a directed response to the in-vitro culture and cryopreservation. PMID:27403857

  6. Conditions Favorable for the Somatic Embryogenesis in Carrot Cell Culture Enhance Expression of the roIC Promoter-GUS Fusion Gene.

    PubMed

    Fujii, N; Uchimiya, H

    1991-01-01

    We obtained carrot (Daucus carota) cells possessing the 5'-noncoding sequence of the ORF12 gene (roIC) of TL-DNA of the Ri plasmid and a structural gene of bacterial beta-glucuronidase by Agrobacterium-mediated transformation. When such cells were cultured in medium containing 2,4-dichlorophenoxyacetic acid, substantial reduction in beta-glucuronidase activity was observed. Upon transferring the cells from a 2,4-D-containing medium to one devoid of 2,4-dichlorophenoxyacetic acid, enhanced expression of beta-glucuronidase in somatic embryo development was recorded. Activation by gibberillic acid and suppression by abscisic acid of beta-glucuronidase activities, in concord with embryogenesis, were also noted. PMID:16667958

  7. Conditions Favorable for the Somatic Embryogenesis in Carrot Cell Culture Enhance Expression of the roIC Promoter-GUS Fusion Gene 1

    PubMed Central

    Fujii, Nobuharu; Uchimiya, Hirofumi

    1991-01-01

    We obtained carrot (Daucus carota) cells possessing the 5′-noncoding sequence of the ORF12 gene (roIC) of TL-DNA of the Ri plasmid and a structural gene of bacterial β-glucuronidase by Agrobacterium-mediated transformation. When such cells were cultured in medium containing 2,4-dichlorophenoxyacetic acid, substantial reduction in β-glucuronidase activity was observed. Upon transferring the cells from a 2,4-D-containing medium to one devoid of 2,4-dichlorophenoxyacetic acid, enhanced expression of β-glucuronidase in somatic embryo development was recorded. Activation by gibberillic acid and suppression by abscisic acid of β-glucuronidase activities, in concord with embryogenesis, were also noted. Images Figure 2 PMID:16667958

  8. Genomewide analysis of small RNAs in nonembryogenic and embryogenic tissues of citrus: microRNA- and siRNA-mediated transcript cleavage involved in somatic embryogenesis.

    PubMed

    Wu, Xiao-Meng; Kou, Shu-Jun; Liu, Yuan-Long; Fang, Yan-Ni; Xu, Qiang; Guo, Wen-Wu

    2015-04-01

    Somatic embryogenesis (SE) is a process of somatic cells becoming dedifferentiated and generating embryos. SE has been widely used in biotechnology as a powerful way of regeneration and a model system for studying plant embryogenesis, but the controlling mechanisms of SE are far from clear. Here, we show the genomewide profiles of miRNAs/siRNAs and their target genes in nonembryogenic and embryogenic tissues of 'Valencia' sweet orange. By high-throughput sequencing (HTS) of small RNAs and RNA degradome tags, we identified 50 known and 45 novel miRNAs, 130 miniature inverted-repeat transposable elements (MITEs) derived, 94 other and 235 phased small interfering RNAs (siRNAs), as well as 203 target genes. The majority of the abundantly expressed miRNAs/siRNAs exhibit lower expression levels in embryogenic callus (EC) or during SE process than in nonembryogenic callus (NEC), which is supposed to derepress the target genes that are involved in development and stress response, thus to activate the biological processes required for cell differentiation. However, the conserved csi-miR156a/b, miR164b and 171c directed suppression of specific transcription factors (TFs) are supposed to inactivate the postembryonic growth thus to maintain normal SE. In this study, miRNA- and siRNA-mediated silencing of target genes was found under sophisticated regulation in citrus SE system; the enhancement effect of specific conserved miRNAs on SE was discussed, providing new clues for future investigation of mechanisms that control SE. PMID:25615015

  9. Formulation of nutrient medium for in vitro somatic embryo induction in Plantago ovata forsk.

    PubMed

    Saha, Priyanka; Bandyopadhyay, Subhendu; Raychaudhuri, Sarmistha Sen

    2011-05-01

    A nutrient medium has been formulated by altering the macro- and micro-elemental concentration in the culture medium for in vitro somatic embryo induction of economically important medicinal plant Plantago ovata Forsk .A comparison was made between induced embryos with normal embryos (produced in Murashige and Skoog (MS) medium) to observe frequency of embryo induction and also to determine regeneration efficiency. In the present investigation, three different media have been formulated. Among them, FM3 (formulated media, treatment 3) was the most suitable for increasing the frequency of somatic embryo production and regeneration of P. ovata Forsk. Better result was obtained using formulated medium than with MS medium. PMID:20405339

  10. 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

  11. 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

  12. Induction of Pluripotency in Mouse Somatic Cells with Lineage Specifiers

    PubMed Central

    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

    2014-01-01

    SUMMARY 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

  13. An unusual abscisic acid and gibberellic acid synergism increases somatic embryogenesis, facilitates its genetic analysis and improves transformation in Medicago truncatula.

    PubMed

    Nolan, Kim E; Song, Youhong; Liao, Siyang; Saeed, Nasir A; Zhang, Xiyi; Rose, Ray J

    2014-01-01

    Somatic embryogenesis (SE) can be readily induced in leaf explants of the Jemalong 2HA genotype of the model legume Medicago truncatula by auxin and cytokinin, but rarely in wild-type Jemalong. Gibberellic acid (GA), a hormone not included in the medium, appears to act in Arabidopsis as a repressor of the embryonic state such that low ABA (abscisic acid): GA ratios will inhibit SE. It was important to evaluate the GA effect in M. truncatula in order to formulate generic SE mechanisms, given the Arabidopsis information. It was surprising to find that low ABA:GA ratios in M. truncatula acted synergistically to stimulate SE. The unusual synergism between GA and ABA in inducing SE has utility in improving SE for regeneration and transformation in M. truncatula. Expression of genes previously shown to be important in M. truncatula SE was not increased. In investigating genes previously studied in GA investigations of Arabidopsis SE, there was increased expression of GA2ox and decreased expression of PICKLE, a negative regulator of SE in Arabidopsis. We suggest that in M. truncatula there are different ABA:GA ratios required for down-regulating the PICKLE gene, a repressor of the embryonic state. In M. truncatula it is a low ABA:GA ratio while in Arabidopsis it is a high ABA:GA ratio. In different species the expression of key genes is probably related to differences in how the hormone networks optimise their expression. PMID:24937316

  14. 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

  15. 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, mi

  16. Transcriptional profiling of genes involved in embryogenic, non-embryogenic calluses and somatic embryogenesis of Valencia sweet orange by SSH-based microarray.

    PubMed

    Ge, Xiao-Xia; Chai, Li-Jun; Liu, Zheng; Wu, Xiao-Meng; Deng, Xiu-Xin; Guo, Wen-Wu

    2012-10-01

    Somatic embryogenesis (SE) is a most promising technology that is used for in vitro germplasm conservation and genetic improvement via biotechnological approaches in citrus. Herein, three suppression subtractive hybridization (SSH) libraries were constructed using calluses of Citrus sinensis cv. 'Valencia' to explore the molecular mechanisms that underlie the SE in citrus. A total of 880 unisequences were identified by microarray screening based on these three SSH libraries. Gene ontology analysis of the differentially expressed genes indicated that nucleolus associated regulation and biogenesis processes, hormone signal transduction, and stress factors might be involved in SE. Transcription factors might also play an important role. LEC1/B3 domain regulatory network genes (LEC1, L1L, FUS3, ABI3, and ABI5) were isolated in citrus SE. Some new transcription factors associated with citrus SE, like a B3 domain containing gene and HB4, were identified. To understand the influence of these isolated genes on SE competence, their expression profiles were compared among callus lines of seven citrus cultivars with different SE competence. The expression dynamics suggested that these genes could be necessary for the SE initiation and might play a role in embryogenic competence maintenance in different cultivars. On the basis of gene expression profiles, an overview of major physiological and biosynthesis processes at different developmental stages during citrus SE is presented. For the first time, these data provide a global resource for transcriptional events important for SE in citrus, and the specific genes offer new information for further investigation on citrus SE maintenance and development. PMID:22622359

  17. The Conformation of a Plasma Membrane-Localized Somatic Embryogenesis Receptor Kinase Complex Is Altered by a Potato Aphid-Derived Effector1[OPEN

    PubMed Central

    Peng, Hsuan-Chieh; Hicks, Glenn R.; Kaloshian, Isgouhi

    2016-01-01

    Somatic embryogenesis receptor kinases (SERKs) are transmembrane receptors involved in plant immunity. Tomato (Solanum lycopersicum) carries three SERK members. One of these, SlSERK1, is required for Mi-1.2-mediated resistance to potato aphids (Macrosiphum euphorbiae). Mi-1.2 encodes a coiled-coil nucleotide-binding leucine-rich repeat protein that in addition to potato aphids confers resistance to two additional phloem-feeding insects and to root-knot nematodes (Meloidogyne spp.). How SlSERK1 participates in Mi-1.2-mediated resistance is unknown, and no Mi-1.2 cognate pest effectors have been identified. Here, we study the mechanistic involvement of SlSERK1 in Mi-1.2-mediated resistance. We show that potato aphid saliva and protein extracts induce the Mi-1.2 defense marker gene SlWRKY72b, indicating that both saliva and extracts contain a Mi-1.2 recognized effector. Resistant tomato cultivar Motelle (Mi-1.2/Mi-1.2) plants overexpressing SlSERK1 were found to display enhanced resistance to potato aphids. Confocal microscopy revealed that Mi-1.2 localizes at three distinct subcellular compartments: the plasma membrane, cytoplasm, and nucleus. Coimmunoprecipitation experiments in these tomato plants and in Nicotiana benthamiana transiently expressing Mi-1.2 and SlSERK1 showed that Mi-1.2 and SlSERK1 colocalize only in a microsomal complex. Interestingly, bimolecular fluorescence complementation analysis showed that the interaction of Mi-1.2 and SlSERK1 at the plasma membrane distinctively changes in the presence of potato aphid saliva, suggesting a model in which a constitutive complex at the plasma membrane participates in defense signaling upon effector binding. PMID:27208261

  18. Evaluation of suitable reference genes for normalization of microRNA expression by real-time reverse transcription PCR analysis during longan somatic embryogenesis.

    PubMed

    Lin, Yu Ling; Lai, Zhong Xiong

    2013-05-01

    Accurate profiling of microRNAs (miRNAs) is an essential step for understanding both developmental and physiological functions of miRNAs. Real-time quantitative PCR (qPCR) is being widely used in miRNA expression studies, but choosing a suitable reference gene is a crucial factor for correct analysis of results. To date, there has been no systematic evaluation of qPCR reference genes for the study of miRNAs during somatic embryogenesis (SE) in the longan tree (Dimocarpus longan). Here, the most stably expressed miRNAs in synchronized longan tree embryogenic cultures at different developmental stages were determined using the geNorm and NormFinder algorithms. Validation qPCR experiments were performed for 24 miRNAs together with a snRNA (U6 snRNA), a rRNA (5S rRNA), and three housekeeping genes. It was found that small RNAs had better expression stability than protein-coding genes, and dlo-miR24 was identified as the most reliable reference gene, followed by dlo-miR168a*, dlo-miR2089*-1 and 5S rRNA. dlo-miR24 was recommended as a normalizer if only a single reference gene was to be used, while the combination of dlo-miR156c, dlo-2089*-1 and 5S rRNA was preferred to normalize miRNA expression data during longan SE. PMID:23454294

  19. The Conformation of a Plasma Membrane-Localized Somatic Embryogenesis Receptor Kinase Complex Is Altered by a Potato Aphid-Derived Effector.

    PubMed

    Peng, Hsuan-Chieh; Mantelin, Sophie; Hicks, Glenn R; Takken, Frank L W; Kaloshian, Isgouhi

    2016-07-01

    Somatic embryogenesis receptor kinases (SERKs) are transmembrane receptors involved in plant immunity. Tomato (Solanum lycopersicum) carries three SERK members. One of these, SlSERK1, is required for Mi-1.2-mediated resistance to potato aphids (Macrosiphum euphorbiae). Mi-1.2 encodes a coiled-coil nucleotide-binding leucine-rich repeat protein that in addition to potato aphids confers resistance to two additional phloem-feeding insects and to root-knot nematodes (Meloidogyne spp.). How SlSERK1 participates in Mi-1.2-mediated resistance is unknown, and no Mi-1.2 cognate pest effectors have been identified. Here, we study the mechanistic involvement of SlSERK1 in Mi-1.2-mediated resistance. We show that potato aphid saliva and protein extracts induce the Mi-1.2 defense marker gene SlWRKY72b, indicating that both saliva and extracts contain a Mi-1.2 recognized effector. Resistant tomato cultivar Motelle (Mi-1.2/Mi-1.2) plants overexpressing SlSERK1 were found to display enhanced resistance to potato aphids. Confocal microscopy revealed that Mi-1.2 localizes at three distinct subcellular compartments: the plasma membrane, cytoplasm, and nucleus. Coimmunoprecipitation experiments in these tomato plants and in Nicotiana benthamiana transiently expressing Mi-1.2 and SlSERK1 showed that Mi-1.2 and SlSERK1 colocalize only in a microsomal complex. Interestingly, bimolecular fluorescence complementation analysis showed that the interaction of Mi-1.2 and SlSERK1 at the plasma membrane distinctively changes in the presence of potato aphid saliva, suggesting a model in which a constitutive complex at the plasma membrane participates in defense signaling upon effector binding. PMID:27208261

  20. Stress-related variation in antioxidative enzymes activity and cell metabolism efficiency associated with embryogenesis induction in isolated microspore culture of triticale (x Triticosecale Wittm.).

    PubMed

    Zur, Iwona; Dubas, Ewa; Golemiec, Elzbieta; Szechyńska-Hebda, Magdalena; Gołebiowska, Gabriela; Wedzony, Maria

    2009-08-01

    Isolated microspore cultures of two spring triticale (x Triticosecale Wittm.) cultivars were used to examine the effect of various stress treatments (either high--32 degrees C or low--5 degrees C temperature with or without nitrogen/carbohydrate starvation) applied to excised anthers on the effectiveness of microspore embryogenesis induction. To quantify the effects of pretreatment conditions, the activity of antioxidative enzymes (catalase, peroxidase and superoxide dismutase) together with respiration rate and heat emission were measured. It was observed that heat shock treatment applied as the only one stress factor increased the activity of antioxidative enzymes which suggests intensive generation of reactive oxygen species. Such pretreatment effectively triggered microspore reprogramming but drastically decreased microspore viability. After low temperature treatment, the activity of antioxidative enzymes was similar to the control subjected only with the stress originated from the transfer to in vitro culture conditions. This pretreatment decreased the number of microspores entering embryogenesis but sustained cell viability and this effect prevailed in the final estimation of microspore embryogenesis effectiveness. For both, low- and high-temperature treatments, interaction with starvation stress was beneficial increasing microspore viability (at 5 degrees C) or efficiency of embryogenesis induction (at 32 degrees C). The latter treatment significantly reduced cell metabolic activity. Physiological background of these effects seems to be different and some hypothetical explanations have been discussed. Received data indicate that in triticale, anther preculture conditions could generate oxidative stress and change the cell metabolic activity which could next be reflected in the cell viability and the efficiency of microspore embryogenesis. PMID:19551385

  1. 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

  2. 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 Dl

  3. Protocols for Callus and Somatic Embryo Initiation for Hibiscus sabdariffa L. (Malvaceae): Influence of Explant Type, Sugar, and Plant Growth Regulators

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A significant work on callus induction and somatic embryogenesis was realized for Hibiscus sabdariffa. Two genotypes (Hibiscus sabdariffa and Hibiscus sabdariffa var. altissima) two sugars (sucrose and glucose) and three concentrations (1 %, 2%, 3%) of each sugar, 3 explant types (root, hypocotyl, c...

  4. Arabidopsis SOMATIC EMBRYOGENESIS RECEPTOR KINASES1 and 2 Are Essential for Tapetum Development and Microspore MaturationW⃞ 111111111111111111111111 100000000000000000000001 100001111000000001000001 100010000100000010100001 100100000010000010100001 101000000001000100010001 101000000001000100010001 101000000001001111111001 101000000001001000001001 100100000010001000001001 100010000100010000000101 100001111000010000000101 100000000000000000000001 111111111111111111111111

    PubMed Central

    Colcombet, Jean; Boisson-Dernier, Aurélien; Ros-Palau, Roc; Vera, Carlos E.; Schroeder, Julian I.

    2005-01-01

    Among the >200 members of the leucine-rich repeat receptor kinase family in Arabidopsis thaliana, only a few have been functionally characterized. Here, we report a critical function in anther development for the SOMATIC EMBRYOGENESIS RECEPTOR KINASE1 (SERK1) and SERK2 genes. Both SERK1 and SERK2 are expressed widely in locules until stage 6 anthers and are more concentrated in the tapetal cell layer later. Whereas serk1 and serk2 single insertion mutants did not show developmental phenotypes, serk1 serk2 double mutants were not able to produce seeds because of a lack of pollen development in mutant anthers. In young buds, double mutant anthers developed normally, but serk1 serk2 microsporangia produced more sporogenous cells that were unable to develop beyond meiosis. Furthermore, serk1 serk2 double mutants developed only three cell layers surrounding the sporogenous cell mass, whereas wild-type anthers developed four cell layers. Further confocal microscopic and molecular analyses showed that serk1 serk2 double mutant anthers lack development of the tapetal cell layer, which accounts for the microspore abortion and male sterility. Taken together, these findings demonstrate that the SERK1 and SERK2 receptor kinases function redundantly as an important control point for sporophytic development controlling male gametophyte production. PMID:16284306

  5. Analysis of expression profiles of selected genes associated with the regenerative property and the receptivity to gene transfer during somatic embryogenesis in Triticum aestivum L.

    PubMed

    Delporte, Fabienne; Muhovski, Yordan; Pretova, Anna; Watillon, Bernard

    2013-10-01

    The physiological, biochemical and molecular mechanisms regulating the initiation of a regenerative pathway remain partially unknown. Efforts to identify the biological features that confer transformation ability, or the tendency of some cells to induce transgene silencing, would help to improve plant genetic engineering. The objective of our study was to monitor the evolution of plant cell competencies in relation to both in vitro tissue culture regeneration and the genetic transformation properties. We used a simple wheat regeneration procedure as an experimental model for studying the regenerative capacity of plant cells and their receptivity to direct gene transfer over the successive steps of the regenerative pathway. Target gene profiling studies and biochemical assays were conducted to follow some of the mechanisms triggered during the somatic-to-embryogenic transition (i.e. dedifferentiation, cell division activation, redifferentiation) and affecting the accessibility of plant cells to receive and stably express the exogenous DNA introduced by bombardment. Our results seem to indicate that the control of cell-cycle (S-phase) and host defense strategies can be crucial determinants of genetic transformation efficiency. The results from studies conducted at macro-, micro- and molecular scales are then integrated into a holistic approach that addresses the question of tissue culture and transgenesis competencies more broadly. Through this multilevel analysis we try to establish functional links between both regenerative capacity and transformation receptiveness, and thereby to provide a more global and integrated vision of both processes, at the core of defense/adaptive mechanisms and survival, between undifferentiated cell proliferation and organization. PMID:24078158

  6. Nonimmunogenic radiation-induced lymphoma: immunity induction by a somatic cell hybrid

    SciTech Connect

    Yefenof, E.; Goldapfel, M.; Ber, R.

    1982-05-01

    The cell line designated PIR-2 is a nonimmunogenic X-ray-induced thymoma of C57BL/6 origin that is unable to induce antitumor immunity in syngeneic lymphocytes in vitro and in mice in vivo. Fusion of PIR-2 with an allogeneic universal fuser A9HT (clone 3c) resulted in the establishment of a somatic cell hybrid designated A9/PIR. C57BL/6 lymphocytes sensitized in vitro with A9/PIR could lyse parental PIR-2 cells, as well as other syngeneic tumors. However, immunization of mice with the hybrid significantly enhanced PIR-2 tumor takes while it partially protected the animals against a challenge with unrelated syngeneic tumors. The results imply that somatic cell hybridization can increase the immunogenicity of an otherwise nonimmunogenic tumor. However, in view of the enhancing effects of hybrid preimmunization on parental tumor cell growth, the possible application of this approach for immunotherapy is questionable.

  7. 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

  8. Screening of medicinal plants for induction of somatic segregation activity in Aspergillus nidulans.

    PubMed

    Ramos Ruiz, A; De la Torre, R A; Alonso, N; Villaescusa, A; Betancourt, J; Vizoso, A

    1996-07-01

    Knowledge about mutagenic properties of plants commonly used in traditional medicine is limited. A screening for genotoxic activity was carried out in aqueous or alcoholic extracts prepared from 13 medicinal plants widely used as folk medicine in Cuba: Lepidium virginicum L. (Brassicaceae): Plantago major L. and Plantago lanceolata L. (Plantaginaceae); Ortosiphon aristatus Blume, Mentha x piperita L., Melissa officinalis L. and Plectranthus amboinicus (Lour.) Spreng. (Lamiaceae); Cymbopogon citratus (DC.) Stapf (Poaceae); Passiflora incarnata L. (Passifloraceae); Zingiber officinale Roscoe (Zingiberaceae); Piper auritum HBK. (Piperaceae); Schinus terebinthifolius Raddi (Anacardeaceae) and Momordica charantia L. (Cucurbitaceae). A plate incorporation assay with Aspergillus nidulans was employed, allowing detection of somatic segregation as a result of mitotic crossing-over, chromosome malsegregation or clastogenic effects. Aspergillus nidulans D-30, a well-marked strain carrying four recessive mutations for conidial color in heterozygosity, which permitted the direct visual detection of segregants, was used throughout this study. As a result, only in the aqueous extract of one of the plants screened (Momordica charantia) a statistical significant increase in the frequency of segregant sectors per colony was observed, and consequently, a genotoxic effect is postulated. PMID:8771452

  9. Technological Overview of iPS Induction from Human Adult Somatic Cells

    PubMed Central

    Bayart, Emilie; Cohen-Haguenauer, Odile

    2013-01-01

    The unlimited proliferation capacity of embryonic stem cells (ESCs) combined with their pluripotent differentiation potential in various lineages raised great interest in both the scientific community and the public at large with hope for future prospects of regenerative medicine. However, since ESCs are derived from human embryos, their use is associated with significant ethical issues preventing broad studies and therapeutic applications. To get around this bottleneck, Takahashi and Yamanaka have recently achieved the conversion of adult somatic cells into ES-like cells via the forced expression of four transcription factors: Oct3/4, Sox2, Klf4 and c-Myc. This first demonstration attracted public attention and opened a new field of stem cells research with both cognitive – such as disease modeling - and therapeutic prospects. This pioneer work just received the 2012 Nobel Prize in Physiology or Medicine. Many methods have been reported since 2006, for the generation of induced pluripotent stem (iPS) cells. Most strategies currently under use are based on gene delivery via gamma-retroviral or lentiviral vectors; some experiments have also been successful using plasmids or transposons-based systems and few with adenovirus. However, most experiments involve integration in the host cell genome with an identified risk for insertional mutagenesis and oncogenic transformation. To circumvent such risks which are deemed incompatible with therapeutic prospects, significant progress has been made with transgene-free reprogramming methods based on e.g.: sendaï virus or direct mRNA or protein delivery to achieve conversion of adult cells into iPS. In this review we aim to cover current knowledge relating to both delivery systems and combinations of inducing factors including chemicals which are used to generate human iPS cells. Finally, genetic instability resulting from the reprogramming process is also being considered as a safety bottleneck for future clinical

  10. Technological overview of iPS induction from human adult somatic cells.

    PubMed

    Bayart, Emilie; Cohen-Haguenauer, Odile

    2013-04-01

    The unlimited proliferation capacity of embryonic stem cells (ESCs) combined with their pluripotent differentiation potential in various lineages raised great interest in both the scientific community and the public at large with hope for future prospects of regenerative medicine. However, since ESCs are derived from human embryos, their use is associated with significant ethical issues preventing broad studies and therapeutic applications. To get around this bottleneck, Takahashi and Yamanaka have recently achieved the conversion of adult somatic cells into ES-like cells via the forced expression of four transcription factors: Oct3/4, Sox2, Klf4 and c-Myc. This first demonstration attracted public attention and opened a new field of stem cells research with both cognitive - such as disease modeling - and therapeutic prospects. This pioneer work just received the 2012 Nobel Prize in Physiology or Medicine. Many methods have been reported since 2006, for the generation of induced pluripotent stem (iPS) cells. Most strategies currently under use are based on gene delivery via gamma-retroviral or lentiviral vectors; some experiments have also been successful using plasmids or transposons- based systems and few with adenovirus. However, most experiments involve integration in the host cell genome with an identified risk for insertional mutagenesis and oncogenic transformation. To circumvent such risks which are deemed incompatible with therapeutic prospects, significant progress has been made with transgene-free reprogramming methods based on e.g.: sendai virus or direct mRNA or protein delivery to achieve conversion of adult cells into iPS. In this review we aim to cover current knowledge relating to both delivery systems and combinations of inducing factors including chemicals which are used to generate human iPS cells. Finally, genetic instability resulting from the reprogramming process is also being considered as a safety bottleneck for future clinical translation

  11. Induction and repair of zinc-finger nuclease-targeted double-strand breaks in Caenorhabditis elegans somatic cells

    PubMed Central

    Morton, Jason; Davis, M. Wayne; Jorgensen, Erik M.; Carroll, Dana

    2006-01-01

    Zinc-finger nucleases are chimeric proteins consisting of engineered zinc-finger DNA-binding motifs attached to an endonuclease domain. These proteins can induce site-specific DNA double-strand breaks in genomic DNA, which are then substrates for cellular repair mechanisms. Here, we demonstrate that engineered zinc-finger nucleases function effectively in somatic cells of the nematode Caenorhabditis elegans. Although gene-conversion events were indistinguishable from uncut DNA in our assay, nonhomologous end joining resulted in mutations at the target site. A synthetic target on an extrachromosomal array was targeted with a previously characterized nuclease, and an endogenous genomic sequence was targeted with a pair of specifically designed nucleases. In both cases, ≈20% of the target sites were mutated after induction of the corresponding nucleases. Alterations in the extrachromosomal targets were largely products of end-filling and blunt ligation. By contrast, alterations in the chromosomal target were mostly deletions. We interpret these differences to reflect the abundance of homologous templates present in the extrachromosomal arrays versus the paucity of such templates for repair of chromosomal breaks. In addition, we find evidence for the involvement of error-prone DNA synthesis in both homologous and nonhomologous pathways of repair. DNA ligase IV is required for efficient end joining, particularly of blunt ends. In its absence, a secondary end-joining pathway relies more heavily on microhomologies in producing deletions. PMID:17060623

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

    PubMed

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

    2014-11-01

    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

  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. 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

  15. Comparative induction of somatic eye-color mutations and sex-linked recessive lethals in Drosophila melanogaster by tryptophan pyrolysates.

    PubMed

    Fujikawa, K; Inagaki, E; Uchibori, M; Kondo, S

    1983-12-01

    The mutagenicities of the products of pyrolysis of tryptophan, Trp-P-1 and Trp-P-2, on Drosophila melanogaster were examined by measuring the effects of these compounds in inducing recessive lethals and somatic eye-color mutations. Since negative results have already been obtained by the standard procedure in males, Trp-P-1 and Trp-P-2 (0.75 to 6 mg/ml) in sucrose solution were given to females for assay of recessive lethal mutations in X-chromosomes. These compounds caused a marginal increase above the control level in the mutation frequency. For the assay of effects on somatic eye-color mutations, Trp-P-1 (200 and 400 ppm) and Trp-P-2 (400 and 800 ppm) were fed to male larvae of a tester strain carrying a genetically unstable marker set of z and w+ on the X-chromosome. These compounds caused dose-dependent increases above the control level in somatic eye-color mutations in adults. It is concluded that, under the conditions used, the somatic eye-color mutation system was more sensitive than the recessive lethal system to the mutagenic effects of tryptophan pyrolysates. PMID:6419091

  16. Enhancement of American chestnut somatic seedling production.

    PubMed

    Andrade, G M; Merkle, S A

    2005-08-01

    Somatic embryogenesis holds promise for mass propagation of American chestnut trees bred or genetically engineered for resistance to chestnut blight. However, low germination frequency of chestnut somatic embryos has limited somatic seedling production for this forest tree. We tested the effects of culture regime (semi-solid versus liquid), cold treatment, AC and somatic embryo morphology (i.e., cotyledon number) on germination and conversion of the somatic embryos. Cold treatment for 12 weeks was critical for conversion of chestnut somatic embryos to somatic seedlings, raising conversion frequencies for one line to 47%, compared to 7% with no cold treatment. AC improved germination and conversion frequency for one line to 77% and 59%, respectively, and kept roots from darkening. For two lines that produced embryos with one, two or three-plus cotyledons, cotyledon number did not affect germination or conversion frequency. We also established embryogenic American chestnut suspension cultures and adapted a fractionation/plating system that allowed us to produce populations of relatively synchronous somatic embryos for multiple lines. Embryos derived from suspension cultures of two lines tested had higher conversion frequencies (46% and 48%) than those from cultures maintained on semi-solid medium (7% and 30%). The improvements in manipulation of American chestnut embryogenic cultures described in this study have allowed over a 100-fold increase in somatic seedling production efficiency over what we reported previously and thus constitute a substantial advance toward the application of somatic embryogenesis for mass clonal propagation of the tree. PMID:15789206

  17. 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

  18. Induction of mutations by tritiated water and 3H-thymidine in Drosophila melanogaster assayed by the somatic zeste-white eye mutation system.

    PubMed

    Rasmuson, A; Xamena, N; Creus, A; Marcos, R

    1988-01-01

    In order to study the mutagenic effect of exposure to tritium, Drosophila melanogaster larvae were treated with tritiated water (3H2O) or tritiated thymidine (3H-TdR) during development. Dose rates ranged from 0.0058 to 0.058 rad/h per nucleus for 3H-TdR and from 0.049 to 0.122 rad/h for 3H2O. Induction of mutations was measured by the appearance of somatic mutations in the eyes of an unstable strain of Drosophila melanogaster. Both substances caused a significant increase in mutation frequency. With the assumption that each mutation observed in this assay is caused by one DNA break, the effectiveness of tritium to create DNA breaks is estimated to be 0.20 breaks per decay for 3H-TdR and 0.27 breaks per decay for 3H2O. PMID:3128734

  19. Comparison of sister chromatid exchange induction in murine germinal and somatic cells by gamma radiation exposure in vivo

    SciTech Connect

    Morales-Ramirez, P.; Mendiola-Cruz, M.T.; Vallarino-Kelly, T.; Rodriguez-Reyes, R.

    1994-12-31

    Sister chromatid exchange (SCE) induction by gamma rays was determined in speratogonia irradiated before or after BrdU incorporation. Furthermore, the comparison of responses obtained in spermatogonia, bone marrow and salivary gland cells was carried out in the cells irradiated after BrdU incorporation, a condition which permits a higher SCE induction. Results indicate that gamma ray exposure of spermatogonia could induce a significant increase in SCE frequency with doses as low as 0.27 Gy, either before or after BrdU incorporation. However, the increase caused by radiation exposure after BrdU incorporation in spermatogonia was nearly three times lower than that obtained in both bone marrow and salivary gland cells. These data suggest that spermatogonia are either more efficient in repairing the gamma ray-induced lesions involved in SCE production or that these cells are less prone to the induction of such lesions. 53 refs., 2 figs., 3 tabs.

  20. Late embryogenesis abundant proteins

    PubMed Central

    Olvera-Carrillo, Yadira; Reyes, José Luis

    2011-01-01

    Late Embryogenesis Abundant (LEA) proteins accumulate at the onset of seed desiccation and in response to water deficit in vegetative plant tissues. The typical LEA proteins are highly hydrophilic and intrinsically unstructured. They have been classified in different families, each one showing distinctive conserved motifs. In this manuscript we present and discuss some of the recent findings regarding their role in plant adaptation to water deficit, as well as those concerning to their possible function, and how it can be related to their intrinsic structural flexibility. PMID:21447997

  1. Induction of Chronic Inflammation and Altered Levels of DNA Hydroxymethylation in Somatic and Germinal Tissues of CBA/CaJ Mice Exposed to (48)Ti Ions.

    PubMed

    Rithidech, Kanokporn Noy; Jangiam, Witawat; Tungjai, Montree; Gordon, Chris; Honikel, Louise; Whorton, Elbert B

    2016-01-01

    Although the lung is one of the target organs at risk for cancer induction from exposure to heavy ions found in space, information is insufficient on cellular/molecular responses linked to increased cancer risk. Knowledge of such events may aid in the development of new preventive measures. Furthermore, although it is known that germinal cells are sensitive to X- or γ-rays, there is little information on the effects of heavy ions on germinal cells. Our goal was to investigate in vivo effects of 1 GeV/n (48)Ti ions (one of the important heavy ions found in the space environment) on somatic (lung) and germinal (testis) tissues collected at various times after a whole body irradiation of CBA/CaJ mice (0, 0.1, 0.25, or 0.5 Gy, delivered at 1 cGy/min). We hypothesized that (48)Ti-ion-exposure induced damage in both tissues. Lung tissue was collected from each mouse from each treatment group at 1 week, 1 month, and 6 months postirradiation. For the testis, we collected samples at 6 months postirradiation. Hence, only late-occurring effects of (48)Ti ions in the testis were studied. There were five mice per treatment group at each harvest time. We investigated inflammatory responses after exposure to (48)Ti ions by measuring the levels of activated nuclear factor kappa B and selected pro-inflammatory cytokines in both tissues of the same mouse. These measurements were coupled with the quantitation of the levels of global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). Our data clearly showed the induction of chronic inflammation in both tissues of exposed mice. A dose-dependent reduction in global 5hmC was found in the lung at all time-points and in testes collected at 6 months postirradiation. In contrast, significant increases in global 5mC were found only in lung and testes collected at 6 months postirradiation from mice exposed to 0.5 Gy of 1 GeV/n (48)Ti ions. Overall, our data showed that (48)Ti ions may create health risks in both

  2. Induction of Chronic Inflammation and Altered Levels of DNA Hydroxymethylation in Somatic and Germinal Tissues of CBA/CaJ Mice Exposed to 48Ti Ions

    PubMed Central

    Rithidech, Kanokporn Noy; Jangiam, Witawat; Tungjai, Montree; Gordon, Chris; Honikel, Louise; Whorton, Elbert B.

    2016-01-01

    Although the lung is one of the target organs at risk for cancer induction from exposure to heavy ions found in space, information is insufficient on cellular/molecular responses linked to increased cancer risk. Knowledge of such events may aid in the development of new preventive measures. Furthermore, although it is known that germinal cells are sensitive to X- or γ-rays, there is little information on the effects of heavy ions on germinal cells. Our goal was to investigate in vivo effects of 1 GeV/n 48Ti ions (one of the important heavy ions found in the space environment) on somatic (lung) and germinal (testis) tissues collected at various times after a whole body irradiation of CBA/CaJ mice (0, 0.1, 0.25, or 0.5 Gy, delivered at 1 cGy/min). We hypothesized that 48Ti-ion-exposure induced damage in both tissues. Lung tissue was collected from each mouse from each treatment group at 1 week, 1 month, and 6 months postirradiation. For the testis, we collected samples at 6 months postirradiation. Hence, only late-occurring effects of 48Ti ions in the testis were studied. There were five mice per treatment group at each harvest time. We investigated inflammatory responses after exposure to 48Ti ions by measuring the levels of activated nuclear factor kappa B and selected pro-inflammatory cytokines in both tissues of the same mouse. These measurements were coupled with the quantitation of the levels of global 5-methylcytosine (5mC) and 5-hydroxymethylcytosine (5hmC). Our data clearly showed the induction of chronic inflammation in both tissues of exposed mice. A dose-dependent reduction in global 5hmC was found in the lung at all time-points and in testes collected at 6 months postirradiation. In contrast, significant increases in global 5mC were found only in lung and testes collected at 6 months postirradiation from mice exposed to 0.5 Gy of 1 GeV/n 48Ti ions. Overall, our data showed that 48Ti ions may create health risks in both lung and

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

    PubMed Central

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

    2016-01-01

    Embryogenesis is an important component in the life cycle of most plant species. Due to the difficulty in embryo isolation, the global gene expression involved in plant embryogenesis, especially the early events following fertilization are largely unknown in radish. In this study, three cDNA libraries from ovules of radish before and after fertilization were sequenced using the Digital Gene Expression (DGE) tag profiling strategy. A total of 5,777 differentially expressed transcripts were detected based on pairwise comparison in the three libraries (0_DAP, 7_DAP and 15_DAP). Results from Gene Ontology (GO) and pathway enrichment analysis revealed that these differentially expressed genes (DEGs) were implicated in numerous life processes including embryo development and phytohormones biosynthesis. Notably, some genes encoding auxin response factor (ARF ), Leafy cotyledon1 (LEC1) and somatic embryogenesis receptor-like kinase (SERK ) known to be involved in radish embryogenesis were differentially expressed. The expression patterns of 30 genes including LEC1-2, AGL9, LRR, PKL and ARF8-1 were validated by qRT-PCR. Furthermore, the cooperation between miRNA and mRNA may play a pivotal role in the radish embryogenesis process. This is the first report on identification of DEGs profiles related to radish embryogenesis and seed development. These results could facilitate further dissection of the molecular mechanisms underlying embryogenesis and seed development in radish. PMID:26902837

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

    PubMed

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

    2016-01-01

    Embryogenesis is an important component in the life cycle of most plant species. Due to the difficulty in embryo isolation, the global gene expression involved in plant embryogenesis, especially the early events following fertilization are largely unknown in radish. In this study, three cDNA libraries from ovules of radish before and after fertilization were sequenced using the Digital Gene Expression (DGE) tag profiling strategy. A total of 5,777 differentially expressed transcripts were detected based on pairwise comparison in the three libraries (0_DAP, 7_DAP and 15_DAP). Results from Gene Ontology (GO) and pathway enrichment analysis revealed that these differentially expressed genes (DEGs) were implicated in numerous life processes including embryo development and phytohormones biosynthesis. Notably, some genes encoding auxin response factor (ARF ), Leafy cotyledon1 (LEC1) and somatic embryogenesis receptor-like kinase (SERK ) known to be involved in radish embryogenesis were differentially expressed. The expression patterns of 30 genes including LEC1-2, AGL9, LRR, PKL and ARF8-1 were validated by qRT-PCR. Furthermore, the cooperation between miRNA and mRNA may play a pivotal role in the radish embryogenesis process. This is the first report on identification of DEGs profiles related to radish embryogenesis and seed development. These results could facilitate further dissection of the molecular mechanisms underlying embryogenesis and seed development in radish. PMID:26902837

  5. Initiation of somatic embryos and regeneration of plants from primordial shoots of 10-year-old somatic white spruce and expression profiles of 11 genes followed during the tissue culture process.

    PubMed

    Klimaszewska, Krystyna; Overton, Catherine; Stewart, Don; Rutledge, Robert G

    2011-03-01

    Adult conifers are notoriously recalcitrant in vegetative propagation and micropropagation that would result in the regeneration of juvenile propagules through somatic embryogenesis (SE) has not been demonstrated to date. Because SE-derived material is more amenable in subsequent tissue culture experiments compared with seed-derived material, a multi-year study was conducted to investigate induction of SE from primordial shoot (PS) explants that were excised from shoot buds of somatic embryo-derived white spruce. The SE induction experiments were carried out first with greenhouse-grown and later with field-grown trees each year from 2002 (2-year-old) to 2010 (10-year-old). Of the four genotypes tested, 893-2 and 893-12 never responded, 893-1 responded up to year 4 and 893-6 consistently responded every year. In 2010, for the first time, three of the 17 893-6 clonal trees produced male strobili as well as SE from cultured PS explants. SE induction was associated with formation of a nodule on the surface of an elongated needle primordium or in callus. Early somatic embryos were detectable after about 3 weeks of culture. Of 11 genes whose expression profiles were followed during the PS cultures, CHAP3A, VP1, WOX2 and SAP2C were expressed exclusively in the early stages of SE, and could potentially be used as markers of embryogenecity. Mature somatic embryos and plants were produced from the explants of responding genotype. Implication of these results for future research on adult conifer recalcitrance in micropropagation is discussed. PMID:21136075

  6. Molecular aspects of somatic-to-embryogenic transition in plants.

    PubMed

    Karami, Omid; Aghavaisi, Behzad; Mahmoudi Pour, Aghil

    2009-11-01

    Somatic embryogenesis (SE) is a model system for understanding the physiological, biochemical, and molecular biological events occurring during plant embryo development. Plant somatic cells have the ability to undergo sustained divisions and give rise to an entire organism. This remarkable feature is called plant cell totipotency. SE is a notable illustration of plant totipotency and involves reprogramming of development in somatic cells toward the embryogenic pathway. Plant growth regularities, especially auxins, are key components as their exogenous application recapitulates the embryogenic potential of the mitotically quiescent somatic cells. It has been observed that there are genetic and also physiological factors that trigger in vitro embryogenesis in various types of plant somatic cells. Analysis of the proteome and transcriptome has led to the identification and characterization of certain genes involved in SE. Most of these genes, however, are upregulated only in the late developmental stages, suggesting that they do not play a direct role in the vegetative-to-embryogenic transition. However, the molecular bases of those triggering factors and the genetic and biochemical mechanisms leading to in vitro embryogenesis are still unknown. Here, we describe the plant factors that participate in the vegetative-to-embryogenic transition and discuss their possible roles in this process. PMID:19763658

  7. A new microspore embryogenesis system under low temperature which mimics zygotic embryogenesis initials, expresses auxin and efficiently regenerates doubled-haploid plants in Brassica napus

    PubMed Central

    2012-01-01

    Background Microspore embryogenesis represents a unique system of single cell reprogramming in plants wherein a highly specialized cell, the microspore, by specific stress treatment, switches its fate towards an embryogenesis pathway. In Brassica napus, a model species for this phenomenon, incubation of isolated microspores at 32°C is considered to be a pre-requisite for embryogenesis induction. Results We have developed a new in vitro system at lower temperature (18°C) to efficiently induce microspore embryogenesis throughout two different developmental pathways: one involving the formation of suspensor-like structures (52.4%) and another producing multicellular embryos without suspensor (13.1%); additionally, a small proportion of non-responsive microspores followed a gametophytic-like development (34.4%) leading to mature pollen. The suspensor-like pathway followed at 18°C involved the establishment of asymmetric identities from the first microspore division and an early polarity leading to different cell fates, suspensor and embryo development, which were formed by cells with different organizations and endogenous auxin distribution, similar to zygotic embryogenesis. In addition, a new strategy for germination of microspore derived embryos was developed for achieving more than 90% conversion of embryos to plantlets, with a predominance of spontaneous doubled haploids plants. Conclusion The present work reveals a novel mechanism for efficient microspore embryogenesis induction in B. napus using continuous low temperature treatment. Results indicated that low temperature applied for longer periods favours an embryogenesis pathway whose first division originates asymmetric cell identities, early polarity establishment and the formation of suspensor-like structures, mimicking zygotic embryogenesis. This new in vitro system provides a convenient tool to analyze in situ the mechanisms underlying different developmental pathways during the microspore reprogramming

  8. Human somatic cells subjected to genetic induction with six germ line-related factors display meiotic germ cell-like features

    PubMed Central

    Medrano, Jose V.; Martínez-Arroyo, Ana M.; Míguez, Jose M.; Moreno, Inmaculada; Martínez, Sebastián; Quiñonero, Alicia; Díaz-Gimeno, Patricia; Marqués-Marí, Ana I.; Pellicer, Antonio; Remohí, Jose; Simón, Carlos

    2016-01-01

    The in vitro derivation of human germ cells has attracted interest in the last years, but their direct conversion from human somatic cells has not yet been reported. Here we tested the ability of human male somatic cells to directly convert into a meiotic germ cell-like phenotype by inducing them with a combination of selected key germ cell developmental factors. We started with a pool of 12 candidates that were reduced to 6, demonstrating that ectopic expression of the germ line-related genes PRDM1, PRDM14, LIN28A, DAZL, VASA and SYCP3 induced direct conversion of somatic cells (hFSK (46, XY), and hMSC (46, XY)) into a germ cell-like phenotype in vitro. Induced germ cell-like cells showed a marked switch in their transcriptomic profile and expressed several post-meiotic germ line related markers, showed meiotic progression, evidence of epigenetic reprogramming, and approximately 1% were able to complete meiosis as demonstrated by their haploid status and the expression of several post-meiotic markers. Furthermore, xenotransplantation assays demonstrated that a subset of induced cells properly colonize the spermatogonial niche. Knowledge obtained from this work can be used to create in vitro models to study gamete-related diseases in humans. PMID:27112843

  9. 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

  10. 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 μM 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 μM) 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 μM) 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

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

    PubMed

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

    2014-11-01

    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 μM 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 μM) 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 μM) 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

  12. 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

  13. 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

  14. 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

  15. 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...

  16. (Why) Does Evolution Favour Embryogenesis?

    PubMed

    Rensing, Stefan A

    2016-07-01

    Complex multicellular organisms typically possess life cycles in which zygotes (formed by gamete fusion) and meiosis occur. Canonical animal embryogenesis describes development from zygote to birth. It involves polarisation of the egg/zygote, asymmetric cell divisions, establishment of axes, symmetry breaking, formation of organs, and parental nutrition (at least in early stages). Similar developmental patterns have independently evolved in other eukaryotic lineages, including land plants and brown algae. The question arises whether embryo-like structures and associated developmental processes recurrently emerge because they are local optima of the evolutionary landscape. To understand which evolutionary principles govern complex multicellularity, we need to analyse why and how similar processes evolve convergently - von Baer's and Haeckel's phylotypic stage revisited in other phyla. PMID:26987708

  17. Linker histone variants control chromatin dynamics during early embryogenesis

    PubMed Central

    Saeki, Hideaki; Ohsumi, Keita; Aihara, Hitoshi; Ito, Takashi; Hirose, Susumu; Ura, Kiyoe; Kaneda, Yasufumi

    2005-01-01

    Complex transitions in chromatin structure produce changes in genome function during development in metazoa. Linker histones, the last component of nucleosomes to be assembled into chromatin, comprise considerably divergent subtypes as compared with core histones. In all metazoa studied, their composition changes dramatically during early embryogenesis concomitant with zygotic gene activation, leading to distinct functional changes that are still poorly understood. Here, we show that early embryonic linker histone B4, which is maternally expressed, is functionally different from somatic histone H1 in influencing chromatin structure and dynamics. We developed a chromatin assembly system with nucleosome assembly protein-1 as a linker histone chaperone. This assay system revealed that maternal histone B4 allows chromatin to be remodeled by ATP-dependent chromatin remodeling factor, whereas somatic histone H1 prevents this remodeling. Structural analysis shows that histone B4 does not significantly restrict the accessibility of linker DNA. These findings define the functional significance of developmental changes in linker histone variants. We propose a model that holds that maternally expressed linker histones are key molecules specifying nuclear dynamics with respect to embryonic totipotency. PMID:15821029

  18. Visualization of somatic deletions mediated by R/RS site-specific recombination and induction of germinal deletions caused by callus differentiation and regeneration in rice.

    PubMed

    Toriyama, K; Chiba, A; Nakagawa, Y

    2003-02-01

    A transgenic rice plant expressing the recombinase of Zygosaccharomyces rouxii under the control of the CaMV 35S promoter was crossed with a transgenic plant carrying a cryptic (beta-glucuronidase) GUS reporter gene, which was activated by recombinase-mediated deletions between two specific recombination sites ( RSs). In F(1) plants, GUS activity was observed as blue spots and stripes in vascular bundles in several parts of the leaves. GUS expression was detected in all of the calli induced from F(1) seeds and throughout the regenerated plants. DNA analysis using the polymerase chain reaction and Southern blotting showed that R/ RS-mediated deletions occurred in all of the cells of the regenerated plants. Stable GUS expression was confirmed in the progeny resulting from self-pollination. Thus, the deletions obtained in the regenerated plants were genetically equivalent to the germinal deletions. These results indicate that the induction of callus differentiation and shoot regeneration is an effective manner to activate the R/ RS system and to produce plants with chromosomal deletions. PMID:12789437

  19. [Relationship between epigenetics of sperm and embryogenesis].

    PubMed

    He, Yan-Fang; Ma, Jie-Hua; Pan, Lian-Jun; Huang, Yu-Feng

    2014-08-01

    Epigenetics comprises the modifications made in gene expressions without changing the DNA sequence itself. Significant epigenetic changes take place during spermatogenesis and fertilization and exert direct influences on embryogenesis. This article provides an overview of the latest researches on epigenetics of male germ cells and a brief discussion on the correlation of sperm with embryogenesis in four aspects: DNA methylation, histone modification, regulation of non-coding RNAs, and genomic imprinting. PMID:25195372

  20. 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

  1. New theory of uterovaginal embryogenesis

    PubMed Central

    Makiyan, Zograb

    2016-01-01

    ABSTRACT Background: The explanation of uterine and vaginal embryogenesis in humans still poses many controversies, because it is difficult to assess early stages of an embryo. The literature review revealed many disagreements in Mullerian theory, inciting some authors to propose new embryological hypotheses. In the original Mullerian theory: the paramesonephral ducts form the Fallopian tubes, uterus and vagina; the mesonephral ducts regress in female embryos. Aims: The aim of this article is to investigate the development of Mullerian ducts in humans, using comparative analysis of fundamental embryological theory and various utero-vaginal anomalies. Material and methods: Between 1998 and 2015, 434 patients with various uterovaginal malformations had been operated on at the Scientific Centre of Obstetrics Gynaecology and Perynatology in Moscow. The anatomies of the uterovaginal malformations in these patients were diagnosed with ultrasound and MRI and then verified during surgical correction by laparoscopy. Results: A systematic comparison of uterovaginal malformations to those in the literature has allowed us to formulate a new theory of embryonic morphogenesis. The new theory is significantly different: ovary, ovarian ligamentum proprium, and ligamentum teres uteri derive from gonadal ridges; Fallopian tubes and vagina completely develop from mesonephral ducts. The uterus develops in the area of intersection between the mesonephral ducts with gonadal ridges by the fusion of the two. Conclusions: The new theory may to induce future embryological studies. The hypothetic possibility that the ovary and endometrium derive from the gonadal ridges could be the key to understanding the enigmatic aetiologies of extragenital and ovarian endometriosis. PMID:26900909

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

    PubMed

    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

  3. 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

  4. Origin of somatic embryos from repetitively embryogenic cultures of walnut (Juglans regia L.): Implications forAgrobacterium-mediated transformation.

    PubMed

    Polito, V S; McGranahan, G; Pinney, K; Leslie, C

    1989-04-01

    Early stages of somatic embryo development from embryogenic cultures ofJuglans regia (Persian or English walnut) are described. Histological examination reveals that secondary somatic embryos arise from cotyledons and hypocotyls of primary embryos cultured in the dark. The embryos originate by transverse to oblique divisions of surface cells. Single-cell origin of the secondary embryos confirms the potential of the repetitive embryogenesis system forAgrobacterium-mediated transformation and regeneration of non-chimeric, transgenic walnut plants. PMID:24233141

  5. Somatic symptom disorder

    MedlinePlus

    ... disorder References American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders . 5th ed. Arlington, VA: American Psychiatric Publishing, 2013. Ferri F. Somatization disorder. In: Ferri FF, ...

  6. 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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  8. Transcript Profiling and Identification of Molecular Markers for Early Microspore Embryogenesis in Brassica napus1[W][OA

    PubMed Central

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

    2007-01-01

    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. Mass production of somatic embryos expressing Escherichia coli heat-labile enterotoxin B subunit in Siberian ginseng.

    PubMed

    Kang, Tae-Jin; Lee, Won-Seok; Choi, Eun-Gyung; Kim, Jae-Whune; Kim, Bang-Geul; Yang, Moon-Sik

    2006-01-24

    The B subunit of Escherichia coli heat-labile toxin (LTB) is a potent mucosal immunogen and immunoadjuvant for co-administered antigens. In order to produce large scale of LTB for the development of edible vaccine, we used transgenic somatic embryos of Siberian ginseng, which is known as medicinal plant. When transgenic somatic embryos were cultured in 130L air-lift type bioreactor, they were developed to mature somatic embryos through somatic embryogenesis and contained approximately 0.36% LTB of the total soluble protein. Enzyme-linked immunosorbent assay indicated that the somatic embryo-synthesized LTB protein bound specifically to GM1-ganglioside, suggesting the LTB subunits formed active pentamers. Therefore, the use of the bioreactor system for expression of LTB proteins in somatic embryos allows for continuous mass production in a short-term period. PMID:16174540

  10. Somatization, Paranoia, and Language.

    ERIC Educational Resources Information Center

    Oxman, Thomas E.; And Others

    1988-01-01

    Free speech of subjects with somatization and paranoia was analyzed to identify and compare self-concept dimensions reflected in their lexical choices. The somatization disorder group conveyed a sense of negativism, distress, and preoccupation with an uncertain self-identity. The paranoid patients portrayed an artificially positive, grandiose…

  11. Defined nuclear changes accompany the reprogramming of the microspore to embryogenesis.

    PubMed

    Testillano, P S; Coronado, M J; Seguí, J M; Domenech, J; González-Melendi, P; Raska, I; Risueño, M C

    2000-04-01

    The switch of the gametophytic developmental program toward pollen embryogenesis to form a haploid plant represents an important alternative for plant breeding. In the present study, the switch of the gametophytic developmental program toward a sporophytic pathway, "embryogenesis," has been studied in three different plant species, Brassica, tobacco, and pepper. The switch has been induced by stress (heat shock) at the very responsive stage of the microspore, which is the vacuolate period. As a result, the cell nucleus undergoes striking structural changes with regard to late gametophytic development, including alterations of biosynthetic activities and proliferative activity. An enrichment in HSP70 heat-shock protein and in the presence of Ntf6-MAP kinase was observed after inductive treatment in the nuclei during early embryogenesis. This apparently reflected the possible roles of these proteins, specifically the protective role of HSP70 for the nuclear machinery, and signal transduction of Ntf6-MAPK for the entry of cells into proliferation. Importantly, the observed nuclear changes were similar in the three species investigated and represented convenient markers for early monitoring of embryogenesis and selection purposes for obtaining double-haploid plants in plant breeding. PMID:10806072

  12. 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

  13. Somatic Literacy. Bringing Somatic Education into Physical Education.

    ERIC Educational Resources Information Center

    Linden, Paul

    1994-01-01

    Examines the profession of physical education and what it could become if it embraced somatic work, explaining the basic concepts and processes of somatic education. Somatic education focuses on the interactions of posture, movement, emotion, thought, self-concept, and cultural values. A case study details somatic education in practice. (SM)

  14. Somatic symptom disorder

    MedlinePlus

    ... disorders; Somatization disorder; Somatiform disorders; Briquet syndrome; Illness anxiety disorder ... and emotionally sensitive to pain and other sensations Family ... to illness anxiety disorder . This is when a person is overly ...

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

    PubMed

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

    2016-02-01

    The freshwater crustacean genus Daphnia has been used extensively in ecological, developmental and ecotoxicological studies. Daphnids produce only female offspring by parthenogenesis under favorable conditions, but in response to various unfavorable conditions and external stimuli, they produce male offspring. Although we reported that exogenous exposure to juvenile hormones and their analogs can induce male offspring even under female-producing conditions, we recently established a male induction system in the Daphnia pulex WTN6 strain simply by changing day-length. This male and female induction system is suitable for understanding the innate mechanisms of sexual dimorphic development in daphnids. Embryogenesis has been described as a normal plate (developmental staging) in various daphnid species; however, all studies have mainly focused on female development. Here, we describe the developmental staging of both sexes during embryogenesis in two representative daphnids, D. pulex and D. magna, based on microscopic time-course observations. Our findings provide the first detailed insights into male embryogenesis in both species, and contribute to the elucidation of the mechanisms underlying sexual differentiation in daphnids. PMID:26853866

  16. Somatic symptoms in depression

    PubMed Central

    Kapfhammer, Hans-Peter

    2006-01-01

    Both painful and nonpainful somatic symptoms essentially characterize clinical states of depressive mood. So far, this well-established psychopathological knowledge has been appreciated only insufficiently by the official diagnostic sys-terms of the Diagnostic and Statistical Manual of Mental Disorders, 4th edition, Text Revision (DSM-IVTR) and the ICD-10 Classification of Mental and Behavioral Disorders. Clinical Descriptions and Diagnostic Guidelines (ICD-10). From a perspective of primary care services, this unmet diagnostic need is deplorable, as the main mode of presenting a depression is by reporting somatic symptoms. This somatic form of presentation, however, significantly contributes to low rates of recognition in primary care. A diagnostic challenge may be seen in the differentiation of a depression with prevailing somatic symptoms from anxiety, somatoform disorders, and medical conditions. When somatic symptoms, particularly painful physical conditions, accompany the already debilitating psychiatric and behavioral symptoms of depression, the course of the illness may be more severe, implying a higher risk of early relapse, chronicity suicide, or mortality due to other natural causes, the economic burden increases considerably, the functional status may be hampered heavily, and health-related quality of life may be lowered dramatically. The neurobiological underpinnings of somatic symptoms in depression may guide more promising treatment approaches. PMID:16889108

  17. Ectopic expression of the Brassica SHOOTMERISTEMLESS attenuates the deleterious effects of the auxin transport inhibitor TIBA on somatic embryo number and morphology.

    PubMed

    Elhiti, Mohamed; Stasolla, Claudio

    2011-02-01

    The auxin transport inhibitor 2,3,5-triiodobenzoic acid (TIBA) is a useful compound for investigating the role of auxin flow during plant growth and development. In Arabidopsis lines, applications of TIBA during the induction phase of somatic embryogenesis inhibit embryo development and induce the differentiation of the meristematic cells of the shoot apical meristem (SAM), leading to the fusion of the cotyledons. These abnormalities were associated to changes in the expression levels of auxin transporter genes (PINs) and endogenous distribution of IAA. Treatments of TIBA caused a rapid accumulation of IAA within the epidermal and cortical root cells of the explants (bent-cotyledon zygotic embryos), as well as in the apical and sub-apical cells of the callus generated by the surface of the cotyledons of the explants. Within the callus only a few cells acquired meristematic characteristics, and this was associated to low expression levels of genes involved in embryogenic cell fate acquisition, such as WUSCHEL (WUS), LEAFY COTYLEDON 1 and 2. All these deleterious effects were attenuated when TIBA was administered to lines over-expressing SHOOT MERISTEMLESS (STM) isolated from Brassica oleracea (Bo), B. napus (Bn), and B. rapa (Br). Of interest, TIBA-treated explants of Arabidopsis lines over-expressing the Brassica STM were able to produce a large number of embryogenic cells and somatic embryos which exhibited a normal morphology and two distinct cotyledons. A proposed reason for this behaviour was ascribed to the ability of the transformed tissue to retain a normal distribution of auxin in the presence of TIBA. Proper localization of auxin might be required for the normal expression of several genes needed for the acquisition of embryogenic competence and formation of somatic embryos. PMID:21421384

  18. Periderm prevents pathological epithelial adhesions during embryogenesis

    PubMed Central

    Richardson, Rebecca J.; Hammond, Nigel L.; Coulombe, Pierre A.; Saloranta, Carola; Nousiainen, Heidi O.; Salonen, Riitta; Berry, Andrew; Hanley, Neil; Headon, Denis; Karikoski, Riitta; Dixon, Michael J.

    2014-01-01

    Appropriate development of stratified, squamous, keratinizing epithelia, such as the epidermis and oral epithelia, generates an outer protective permeability barrier that prevents water loss, entry of toxins, and microbial invasion. During embryogenesis, the immature ectoderm initially consists of a single layer of undifferentiated, cuboidal epithelial cells that stratifies to produce an outer layer of flattened periderm cells of unknown function. Here, we determined that periderm cells form in a distinct pattern early in embryogenesis, exhibit highly polarized expression of adhesion complexes, and are shed from the outer surface of the embryo late in development. Mice carrying loss-of-function mutations in the genes encoding IFN regulatory factor 6 (IRF6), IκB kinase-α (IKKα), and stratifin (SFN) exhibit abnormal epidermal development, and we determined that mutant animals exhibit dysfunctional periderm formation, resulting in abnormal intracellular adhesions. Furthermore, tissue from a fetus with cocoon syndrome, a lethal disorder that results from a nonsense mutation in IKKA, revealed an absence of periderm. Together, these data indicate that periderm plays a transient but fundamental role during embryogenesis by acting as a protective barrier that prevents pathological adhesion between immature, adhesion-competent epithelia. Furthermore, this study suggests that failure of periderm formation underlies a series of devastating birth defects, including popliteal pterygium syndrome, cocoon syndrome, and Bartsocas-Papas syndrome. PMID:25133425

  19. Somatization, paranoia, and language.

    PubMed

    Oxman, T E; Rosenberg, S D; Schnurr, P P; Tucker, G J

    1988-02-01

    Somatization and paranoia are circumscribed distortions of reality that are impervious to the normative process of consensual validation. These distortions are often postulated as a means of bolstering lowered self-esteem. We used computerized content analysis of the free speech of patients with these disorders in order to identify and compare dimensions of self-concept reflected in their lexical choices. Interestingly, patients with these disorders differed in the themes prominent in their speech. The higher frequency categories used by the somatization disorder group conveyed an overwhelming sense of negativism, distress, and a preoccupation with an uncertain self-identity. In contrast, the categories used by the paranoid patients portrayed an artificially positive, grandiose self-image and a defensive abstractness. Our exploratory analysis suggests that circumscribed distortions of reality in somatization and paranoid disorders are not associated with the same common defensive style attempting to bolster self-esteem. PMID:3343385

  20. 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...

  1. Reprogramming mammalian somatic cells.

    PubMed

    Rodriguez-Osorio, N; Urrego, R; Cibelli, J B; Eilertsen, K; Memili, E

    2012-12-01

    Somatic cell nuclear transfer (SCNT), the technique commonly known as cloning, permits transformation of a somatic cell into an undifferentiated zygote with the potential to develop into a newborn animal (i.e., a clone). In somatic cells, chromatin is programmed to repress most genes and express some, depending on the tissue. It is evident that the enucleated oocyte provides the environment in which embryonic genes in a somatic cell can be expressed. This process is controlled by a series of epigenetic modifications, generally referred to as "nuclear reprogramming," which are thought to involve the removal of reversible epigenetic changes acquired during cell differentiation. A similar process is thought to occur by overexpression of key transcription factors to generate induced pluripotent stem cells (iPSCs), bypassing the need for SCNT. Despite its obvious scientific and medical importance, and the great number of studies addressing the subject, the molecular basis of reprogramming in both reprogramming strategies is largely unknown. The present review focuses on the cellular and molecular events that occur during nuclear reprogramming in the context of SCNT and the various approaches currently being used to improve nuclear reprogramming. A better understanding of the reprogramming mechanism will have a direct impact on the efficiency of current SCNT procedures, as well as iPSC derivation. PMID:22979962

  2. 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…

  3. 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.

  4. 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

  5. Somatic mutations in the variable regions of a human IgG anti-double-stranded DNA autoantibody suggest a role for antigen in the induction of systemic lupus erythematosus.

    PubMed

    van Es, J H; Gmelig Meyling, F H; van de Akker, W R; Aanstoot, H; Derksen, R H; Logtenberg, T

    1991-02-01

    The processes that govern the generation of pathogenic anti-DNA autoantibodies in human systemic lupus erythematosus (SLE) are largely unknown. Autoantibodies may arise as a consequence of polyclonal B cell activation and/or antigen-driven B cell activation and selection. The role of these processes in humoral autoimmunity may be studied by molecular genetic analysis of immunoglobulin (Ig) variable (V) regions of antibodies that are characteristic of SLE. We have analyzed the gene elements that encode a high affinity, IgG anti-double-stranded DNA autoantibody secreted by a monoclonal Epstein-Barr virus (EBV)-transformed cell line derived from a patient with active SLE. In addition, we have identified, cloned, and sequenced the germline counterparts of the VH and VL genes expressed in this autoantibody. The comparison of both sets of gene elements shows that the autoantibody VH and VL regions harbor numerous somatic mutations characteristic of an antigen-driven immune response. The light chain expressed in this autoantibody is a somatically mutated variant of the kv325 germline gene that is frequently associated with paraproteins having autoantibody activity and with Ig molecules produced by malignant B cells that express the CD5 antigen. Furthermore, the utilized DH segment has been repeatedly found in multireactive, low affinity IgM anti-DNA autoantibodies from SLE patients and healthy individuals. These results suggest that pathogenic IgG anti-DNA autoantibodies in human SLE may arise through antigen-driven selection of somatic mutations in the gene elements that frequently encode multireactive IgM autoantibodies. PMID:1899104

  6. 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.

  7. 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.

  8. Somatic embryogenesis and massive shoot regeneration from immature embryo explants of tef.

    PubMed

    Gugsa, Likyelesh; Kumlehn, Jochen

    2011-01-01

    Tef (Eragrostis tef) provides a major source of human nutrition in the Horn of Africa, but biotechnology has had little impact on its improvement to date. Here, we report the elaboration of an in vitro regeneration protocol, based on the use of immature zygotic embryos as explant. Explant size was an important determinant of in vitro regeneration efficiency, as was the formulation of the culture medium. Optimal results were obtained by culturing 0.2-0.35 mm embryo explants on a medium containing KBP minerals, 9.2-13.8 μM 2,4-dichlorophenoxyacetic acid, 6 mM glutamine, and 0.5% Phytagel. Although this protocol was effective for both the improved cultivar "DZ-01-196" and the landrace "Fesho", the former produced consistently more embryogenic tissue and a higher number of regenerants. An average of more than 2,800 shoots could be obtained from each "DZ-01-196" explant after 12 weeks of in vitro culture. These shoots readily formed roots, and plantlets transferred to soil were able to develop into morphologically normal, fertile plants. This regeneration and multiplication system should allow for the application of a range of biotechnological methods to tef. PMID:22028975

  9. Aneuploidy in mammalian somatic cells in vivo.

    PubMed

    Cimino, M C; Tice, R R; Liang, J C

    1986-01-01

    Aneuploidy is an important potential source of human disease and of reproductive failure. Nevertheless, the ability of chemical agents to induce aneuploidy has been investigated only sporadically in intact (whole-animal) mammalian systems. A search of the available literature from the EMCT Aneuploidy File (for years 1970-1983) provided 112 papers that dealt with aneuploidy in mammalian somatic cells in vivo. 59 of these papers did not meet minimal criteria for analysis and were rejected from subsequent review. Of the remaining 53 papers that dealt with aneuploidy induction by chemical agents in mammalian somatic cells in vivo, only 3 (6%) contained data that were considered to be supported conclusively by adequate study designs, execution, and reporting. These 3 papers dealt with 2 chemicals, one of which, mercury, was negative for aneuploidy induction in humans, and the other, pyrimethamine, was positive in an experimental rodent study. The majority of papers (94%) were considered inconclusive for a variety of reasons. The most common reasons for calling a study inconclusive were (a) combining data on hyperploidy with those on hypoploidy and/or polyploidy, (b) an inadequate or unspecified number of animals and/or cells per animal scored per treatment group, and (c) poor data presentation such that animal-to-animal variability could not be assessed. Suggestions for protocol development are made, and the future directions of research into aneuploidy induction are discussed. PMID:3941670

  10. Isolation of an embryogenic line from non-embryogenic Brassica napus cv. Westar through microspore embryogenesis

    PubMed Central

    Malik, Meghna R.; Wang, Feng; Dirpaul, Joan M.; Zhou, Ning; Hammerlindl, Joe; Keller, Wilf; Abrams, Suzanne R.; Ferrie, Alison M. R.; Krochko, Joan E.

    2008-01-01

    Brassica napus cultivar Westar is non-embryogenic under all standard protocols for induction of microspore embryogenesis; however, the rare embryos produced in Westar microspore cultures, induced with added brassinosteroids, were found to develop into heritably stable embryogenic lines after chromosome doubling. One of the Westar-derived doubled haploid (DH) lines, DH-2, produced up to 30% the number of embryos as the highly embryogenic B. napus line, Topas DH4079. Expression analysis of marker genes for embryogenesis in Westar and the derived DH-2 line, using real-time reverse transcription-PCR, revealed that the timely expression of embryogenesis-related genes such as LEAFY COTYLEDON1 (LEC1), LEC2, ABSCISIC ACID INSENSITIVE3, and BABY BOOM1, and an accompanying down-regulation of pollen-related transcripts, were associated with commitment to embryo development in Brassica microspores. Microarray comparisons of 7 d cultures of Westar and Westar DH-2, using a B. napus seed-focused cDNA array (10 642 unigenes), identified highly expressed genes related to protein synthesis, translation, and response to stimulus (Gene Ontology) in the embryogenic DH-2 microspore-derived cell cultures. In contrast, transcripts for pollen-expressed genes were predominant in the recalcitrant Westar microspores. Besides being embryogenic, DH-2 plants showed alterations in morphology and architecture as compared with Westar, for example epinastic leaves, non-abscised petals, pale flower colour, and longer lateral branches. Auxin, cytokinin, and abscisic acid (ABA) profiles in young leaves, mature leaves, and inflorescences of Westar and DH-2 revealed no significant differences that could account for the alterations in embryogenic potential or phenotype. Various mechanisms accounting for the increased capacity for embryogenesis in Westar-derived DH lines are considered. PMID:18552352

  11. Isolation of an embryogenic line from non-embryogenic Brassica napus cv. Westar through microspore embryogenesis.

    PubMed

    Malik, Meghna R; Wang, Feng; Dirpaul, Joan M; Zhou, Ning; Hammerlindl, Joe; Keller, Wilf; Abrams, Suzanne R; Ferrie, Alison M R; Krochko, Joan E

    2008-01-01

    Brassica napus cultivar Westar is non-embryogenic under all standard protocols for induction of microspore embryogenesis; however, the rare embryos produced in Westar microspore cultures, induced with added brassinosteroids, were found to develop into heritably stable embryogenic lines after chromosome doubling. One of the Westar-derived doubled haploid (DH) lines, DH-2, produced up to 30% the number of embryos as the highly embryogenic B. napus line, Topas DH4079. Expression analysis of marker genes for embryogenesis in Westar and the derived DH-2 line, using real-time reverse transcription-PCR, revealed that the timely expression of embryogenesis-related genes such as LEAFY COTYLEDON1 (LEC1), LEC2, ABSCISIC ACID INSENSITIVE3, and BABY BOOM1, and an accompanying down-regulation of pollen-related transcripts, were associated with commitment to embryo development in Brassica microspores. Microarray comparisons of 7 d cultures of Westar and Westar DH-2, using a B. napus seed-focused cDNA array (10 642 unigenes), identified highly expressed genes related to protein synthesis, translation, and response to stimulus (Gene Ontology) in the embryogenic DH-2 microspore-derived cell cultures. In contrast, transcripts for pollen-expressed genes were predominant in the recalcitrant Westar microspores. Besides being embryogenic, DH-2 plants showed alterations in morphology and architecture as compared with Westar, for example epinastic leaves, non-abscised petals, pale flower colour, and longer lateral branches. Auxin, cytokinin, and abscisic acid (ABA) profiles in young leaves, mature leaves, and inflorescences of Westar and DH-2 revealed no significant differences that could account for the alterations in embryogenic potential or phenotype. Various mechanisms accounting for the increased capacity for embryogenesis in Westar-derived DH lines are considered. PMID:18552352

  12. Late Embryogenesis Abundant (LEA) proteins in legumes

    PubMed Central

    Battaglia, Marina; Covarrubias, Alejandra A.

    2013-01-01

    Plants are exposed to different external conditions that affect growth, development, and productivity. Water deficit is one of these adverse conditions caused by drought, salinity, and extreme temperatures. Plants have developed different responses to prevent, ameliorate or repair the damage inflicted by these stressful environments. One of these responses is the activation of a set of genes encoding a group of hydrophilic proteins that typically accumulate to high levels during seed dehydration, at the last stage of embryogenesis, hence named Late Embryogenesis Abundant (LEA) proteins. LEA proteins also accumulate in response to water limitation in vegetative tissues, and have been classified in seven groups based on their amino acid sequence similarity and on the presence of distinctive conserved motifs. These proteins are widely distributed in the plant kingdom, from ferns to angiosperms, suggesting a relevant role in the plant response to this unfavorable environmental condition. In this review, we analyzed the LEA proteins from those legumes whose complete genomes have been sequenced such as Phaseolus vulgaris, Glycine max, Medicago truncatula, Lotus japonicus, Cajanus cajan, and Cicer arietinum. Considering their distinctive motifs, LEA proteins from the different groups were identified, and their sequence analysis allowed the recognition of novel legume specific motifs. Moreover, we compile their transcript accumulation patterns based on publicly available data. In spite of the limited information on these proteins in legumes, the analysis and data compiled here confirm the high correlation between their accumulation and water deficit, reinforcing their functional relevance under this detrimental conditions. PMID:23805145

  13. Late Embryogenesis Abundant (LEA) proteins in legumes.

    PubMed

    Battaglia, Marina; Covarrubias, Alejandra A

    2013-01-01

    Plants are exposed to different external conditions that affect growth, development, and productivity. Water deficit is one of these adverse conditions caused by drought, salinity, and extreme temperatures. Plants have developed different responses to prevent, ameliorate or repair the damage inflicted by these stressful environments. One of these responses is the activation of a set of genes encoding a group of hydrophilic proteins that typically accumulate to high levels during seed dehydration, at the last stage of embryogenesis, hence named Late Embryogenesis Abundant (LEA) proteins. LEA proteins also accumulate in response to water limitation in vegetative tissues, and have been classified in seven groups based on their amino acid sequence similarity and on the presence of distinctive conserved motifs. These proteins are widely distributed in the plant kingdom, from ferns to angiosperms, suggesting a relevant role in the plant response to this unfavorable environmental condition. In this review, we analyzed the LEA proteins from those legumes whose complete genomes have been sequenced such as Phaseolus vulgaris, Glycine max, Medicago truncatula, Lotus japonicus, Cajanus cajan, and Cicer arietinum. Considering their distinctive motifs, LEA proteins from the different groups were identified, and their sequence analysis allowed the recognition of novel legume specific motifs. Moreover, we compile their transcript accumulation patterns based on publicly available data. In spite of the limited information on these proteins in legumes, the analysis and data compiled here confirm the high correlation between their accumulation and water deficit, reinforcing their functional relevance under this detrimental conditions. PMID:23805145

  14. Specification of the somatic musculature in Drosophila†

    PubMed Central

    Dobi, Krista C.; Schulman, Victoria K.; Baylies, Mary K.

    2015-01-01

    The somatic muscle system formed during Drosophila embryogenesis is required for larvae to hatch, feed, and crawl. This system is replaced in the pupa by a new adult muscle set, responsible for activities such as feeding, walking, and flight. Both the larval and adult muscle systems are comprised of distinct muscle fibers to serve these specific motor functions. In this way, the Drosophila musculature is a valuable model for patterning within a single tissue: while all muscle cells share properties such as the contractile apparatus, properties such as size, position, and number of nuclei are unique for a particular muscle. In the embryo, diversification of muscle fibers relies first on signaling cascades that pattern the mesoderm. Subsequently, the combinatorial expression of specific transcription factors leads muscle fibers to adopt particular sizes, shapes, and orientations. Adult muscle precursors (AMPs), set aside during embryonic development, proliferate during the larval phases and seed the formation of the abdominal, leg, and flight muscles in the adult fly. Adult muscle fibers may either be formed de novo from the fusion of the AMPs, or are created by the binding of AMPs to an existing larval muscle. While less is known about adult muscle specification compared to the larva, expression of specific transcription factors is also important for its diversification. Increasingly, the mechanisms required for the diversification of fly muscle have found parallels in vertebrate systems and mark Drosophila as a robust model system to examine questions about how diverse cell types are generated within an organism. PMID:25728002

  15. Somatization disorders in dermatology.

    PubMed

    Gupta, Madhulika A

    2006-02-01

    This paper reviews a wide range of somatization-related symptoms that are encountered in dermatology. These include the unexplained cutaneous sensory syndromes especially the cutaneous dysesthesias associated with pain, numbness and pruritus; traumatic memories in post-traumatic stress disorder (PTSD) which are experienced on a sensory level as 'body memories' and may present as local or generalized pruritic states, urticaria and angioedema; and unexplained flushing reactions and profuse perspiration, in addition to unexplained exacerbations of stress-reactive dermatoses such as psoriasis and atopic eczema secondary to the autonomic hyperarousal in PTSD; classic 'pseudoneurologic' symptoms associated with dissociation including unexplained loss of touch or pain, in addition to the self-induced dermatoses such as dermatitis artefacta and trichotillomania that are encountered with dissociative states; and body dysmorphic disorder where the patient often presents with a somatic preoccupation involving the skin or hair. PMID:16451879

  16. AID AND SOMATIC HYPERMUTATION

    PubMed Central

    Maul, Robert W.; Gearhart, Patricia J.

    2010-01-01

    In response to an assault by foreign organisms, peripheral B cells can change their antibody affinity and isotype by somatically mutating their genomic DNA. The ability of a cell to modify its DNA is exceptional in light of the potential consequences of genetic alterations to cause human disease and cancer. Thus, as expected, this mechanism of antibody diversity is tightly regulated and coordinated through one protein, activation induced deaminase (AID). AID produces diversity by converting cytosine to uracil within the immunoglobulin loci. The deoxyuracil residue is mutagenic when paired with deoxyguanosine, since it mimics thymidine during DNA replication. Additionally, B cells can manipulate the DNA repair pathways so that deoxyuracils are not faithfully repaired. Therefore, an intricate balance exists which is regulated at multiple stages to promote mutation of immunoglobulin genes, while retaining integrity of the rest of the genome. Here we discuss and summarize the current understanding of how AID functions to cause somatic hypermutation. PMID:20510733

  17. Reprogramming of somatic cells.

    PubMed

    Rajasingh, Johnson

    2012-01-01

    Reprogramming of adult somatic cells into pluripotent stem cells may provide an attractive source of stem cells for regenerative medicine. It has emerged as an invaluable method for generating patient-specific stem cells of any cell lineage without the use of embryonic stem cells. A revolutionary study in 2006 showed that it is possible to convert adult somatic cells directly into pluripotent stem cells by using a limited number of pluripotent transcription factors and is called as iPS cells. Currently, both genomic integrating viral and nonintegrating nonviral methods are used to generate iPS cells. However, the viral-based technology poses increased risk of safety, and more studies are now focused on nonviral-based technology to obtain autologous stem cells for clinical therapy. In this review, the pros and cons of the present iPS cell technology and the future direction for the successful translation of this technology into the clinic are discussed. PMID:22917226

  18. 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

  19. 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 μM) 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

  20. 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 μM) 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

  1. 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

  2. Somatic complaints in frontotemporal dementia

    PubMed Central

    Landqvist Waldö, Maria; Santillo, Alexander Frizell; Gustafson, Lars; Englund, Elisabet; Passant, Ulla

    2014-01-01

    Frontotemporal dementia (FTD) is associated with a broad spectrum of clinical characteristics. The objective of this study was to analyze the prevalence of unexplained somatic complaints in neuropathologically verified FTD. We also examined whether the somatic presentations correlated with protein pathology or regional brain pathology and if the patients with these somatic features showed more depressive traits. Ninety-seven consecutively neuropathologically verified FTLD patients were selected. All 97 patients were part of a longitudinal study of FTD and all medical records were systematically reviewed. The somatic complaints focused on were headache, musculoskeletal, gastro/urogenital and abnormal pain response. Symptoms of somatic character (either somatic complaints and/or abnormal pain response) were found in 40.2%. These patients did not differ from the total group with regard to gender, age at onset or duration. Six patients showed exaggerated reactions to sensory stimuli, whereas three patients showed reduced response to pain. Depressive traits were present in 38% and did not correlate with somatic complaints. Suicidal behavior was present in 17 patients, in 10 of these suicidal behavior was concurrent with somatic complaints. No clear correlation between somatic complaints and brain protein pathology, regional pathology or asymmetric hemispherical atrophy was found. Our results show that many FTD patients suffer from unexplained somatic complaints before and/or during dementia where no clear correlation can be found with protein pathology or regional degeneration. Somatic complaints are not covered by current diagnostic criteria for FTD, but need to be considered in diagnostics and care. The need for prospective studies with neuropathological follow up must be stressed as these phenomena remain unexplained, misinterpreted, bizarre and, in many cases, excruciating. PMID:25232513

  3. Estrogen receptors bind to and activate the HOXC4/HoxC4 promoter to potentiate HoxC4-mediated activation-induced cytosine deaminase induction, immunoglobulin class switch DNA recombination, and somatic hypermutation.

    PubMed

    Mai, Thach; Zan, Hong; Zhang, Jinsong; Hawkins, J Seth; Xu, Zhenming; Casali, Paolo

    2010-11-26

    Estrogen enhances antibody and autoantibody responses through yet to be defined mechanisms. It has been suggested that estrogen up-regulates the expression of activation-induced cytosine deaminase (AID), which is critical for antibody class switch DNA recombination (CSR) and somatic hypermutation (SHM), through direct activation of this gene. AID, as we have shown, is induced by the HoxC4 homeodomain transcription factor, which binds to a conserved HoxC4/Oct site in the AICDA/Aicda promoter. Here we show that estrogen-estrogen receptor (ER) complexes do not directly activate the AID gene promoter in B cells undergoing CSR. Rather, they bind to three evolutionarily conserved and cooperative estrogen response elements (EREs) we identified in the HOXC4/HoxC4 promoter. By binding to these EREs, ERs synergized with CD154 or LPS and IL-4 signaling to up-regulate HoxC4 expression, thereby inducing AID and CSR without affecting B cell proliferation or plasmacytoid differentiation. Estrogen administration in vivo significantly potentiated CSR and SHM in the specific antibody response to the 4-hydroxy-3-nitrophenylacetyl hapten conjugated with chicken γ-globulin. Ablation of HoxC4 (HoxC4(-/-)) abrogated the estrogen-mediated enhancement of AID gene expression and decreased CSR and SHM. Thus, estrogen enhances AID expression by activating the HOXC4/HoxC4 promoter and inducing the critical AID gene activator, HoxC4. PMID:20855884

  4. 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

  5. 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 Central

    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

  6. Expression of developmental genes during early embryogenesis of Hydra.

    PubMed

    Fröbius, Andreas C; Genikhovich, Gregory; Kürn, Ulrich; Anton-Erxleben, Friederike; Bosch, Thomas C G

    2003-09-01

    Hydra is a classical model to study key features of embryogenesis such as axial patterning and stem cell differentiation. In contrast to other organisms where these mechanisms are active only during embryonic development, in Hydra they can be studied in adults. The underlying assumption is that the machinery governing adult patterning mimics regulatory mechanisms which are also active during early embryogenesis. Whether, however, Hydra embryogenesis is governed by the same mechanisms which are controlling adult patterning, remains to be shown. In this paper, in precisely staged Hydra embryos, we examined the expression pattern of 15 regulatory genes shown previously to play a role in adult patterning and cell differentiation. RT-PCR revealed that most of the genes examined were expressed in rather late embryonic stages. In situ hybridization, nuclear run-on experiments, and staining of nucleolar organizer region-associated proteins indicated that genes expressed in early embryos are transcribed in the engulfed "nurse cells" (endocytes). This is the first direct evidence that endocytes in Hydra not only provide nutrients to the developing oocyte but also produce maternal factors critical for embryogenesis. Our findings are an initial step towards understanding the molecular machinery controlling embryogenesis of a key group of basal metazoans and raise the possibility that in Hydra there are differences in the mechanisms controlling embryogenesis and adult patterning. PMID:12883882

  7. Somatic mosaicism and variable expressivity.

    PubMed

    Gottlieb, B; Beitel, L K; Trifiro, M A

    2001-02-01

    For more than 50 years geneticists have assumed that variations in phenotypic expression are caused by alterations in genotype. Recent evidence shows that 'simple' mendelian disorders or monogenic traits are often far from simple, exhibiting phenotypic variation (variable expressivity) that cannot be explained entirely by a gene or allelic alteration. In certain cases of androgen insensitivity syndrome caused by identical mutations in the androgen receptor gene, phenotypic variability is caused by somatic mosaicism, that is, somatic mutations that occur only in certain androgen-sensitive cells. Recently, more than 30 other genetic conditions that exhibit variable expressivity have been linked to somatic mosaicism. Somatic mutations have also been identified in diseases such as prostate and colorectal cancer. Therefore, the concept of somatic mutations and mosaicism is likely to have far reaching consequences for genetics, in particular in areas such as genetic counseling. PMID:11173116

  8. Possible effect from shear stress on maturation of somatic embryos of Norway spruce (Picea abies).

    PubMed

    Sun, Hong; Aidun, Cyrus K; Egertsdotter, Ulrika

    2011-05-01

    Somatic embryogenesis is the only method with the potential for industrial scale clonal propagation of conifers. Implementation of the method has so far been hampered by the extensive manual labor required for development of the somatic embryos into plants. The utilization of bioreactors is limited since the somatic embryos will not mature and germinate under liquid culture conditions. The negative effect on mature embryo yields from liquid culture conditions has been previously described. We have described the negative effects of shear stress on the development of early stage somatic embryos (proembryogenic masses; PEMs) at shear stresses of 0.086 and 0.14 N/m(2). In the present study, additional flow rates were studied to determine the effects of shear stress at lower rates resembling shear stress in a suspension culture flask. The results showed that shear stress at 0.009, 0.014, and 0.029 N/m(2) inhibited the PEM expansions comparing with the control group without shear stress. This study also provides validation for the cross-correlation method previously developed to show the effect of shear stress on early stage embryo suspensor cell formation and polarization. Furthermore, shear stress was shown to positively affect the uptake of water into the cells. The results indicate that the plasmolyzing effect from macromolecules added to liquid culture medium to stimulate maturation of the embryos are affected by liquid culture conditions and thus can affect the conversion of PEMs into mature somatic embryos. PMID:21449024

  9. Requirement of SLD5 for Early Embryogenesis

    PubMed Central

    Nagahama, Yumi; Gong, Zhi-Yuan; Asano, Masahide; Oshima, Hiroko; Oshima, Masanobu; Fujio, Yasushi; Takakura, Nobuyuki

    2013-01-01

    SLD5 forms a GINS complex with PSF1, PSF2 and PSF3, which is essential for the initiation of DNA replication in lower eukaryotes. Although these components are conserved in mammals, their biological function is unclear. We show here that targeted disruption of SLD5 in mice causes a defect in cell proliferation in the inner cell mass, resulting in embryonic lethality at the peri-implantation stage, indicating that SLD5 is essential for embryogenesis. Moreover, this phenotype of SLD5 mutant mice is quite similar compared with that of PSF1 mutant mice. We have previously reported that haploinsufficiency of PSF1 resulted in failure of acute proliferation of bone marrow hematopoietic stem cells (HSCs) during reconstitution of bone marrow ablated by 5-FU treatment. Since SLD5 was highly expressed in bone marrow, we investigated its involvement in bone marrow reconstitution after bone marrow ablation as observed in PSF1 heterozygous mutant mice. However, heterozygous deletion of the SLD5 gene was found not to significantly affect bone marrow reconstitution. On the other hand, abundant SLD5 expression was observed in human cancer cell lines and heterozygous deletion of the gene attenuated tumor progression in a murine model of spontaneous gastric cancer. These indicated that requirement and dependency of SLD5 for cell proliferation is different in different cell types. PMID:24244394

  10. Environmental magnetic fields: Influences on early embryogenesis

    SciTech Connect

    Cameron, I.L.; Hardman, W.E.; Winters, W.D.; Zimmerman, S.; Zimmerman, A.M. )

    1993-04-01

    A 10-mG, 50 to 60-Hz magnetic field is in the intensity and frequency range that people worldwide are often exposed to in homes and in the workplace. Studies about the effects of 50- to 100-Hz electromagnetic fields on various species of animal embryos (fish, chick, fly, sea urchin, rat, and mouse) indicate that early stages of embryonic development are responsive to fluctuating magnetic fields. Chick, sea urchin, and mouse embryos are responsive to magnetic field intensities of 10-100 mG. Results from studies on sea urchin embryos indicate that exposure to conditions of rotating 60-Hz magnetic fields, e.g., similar to those in our environment, interferes with cell proliferation at the morula stage in a manner dependent on field intensity. The cleavage stages, prior to the 64-cell stage, were not delayed by this rotating 60-Hz magnetic field suggesting that the ionic surges, DNA replication, and translational events essential for early cleavage stages were not significantly altered. Studies of histone synthesis in early sea urchin embryos indicated that the rotating 60-Hz magnetic field decreased zygotic expression of early histone genes at the morula stage and suggests that this decrease in early histone production was limiting to cell proliferation. Whether these comparative observations from animal development studies will be paralleled by results from studies of human embryogenesis, as suggested by some epidemiology studies, has yet to be established. 38 refs.

  11. Gene expression throughout a vertebrate's embryogenesis

    PubMed Central

    2011-01-01

    Background Describing the patterns of gene expression during embryonic development has broadened our understanding of the processes and patterns that define morphogenesis. Yet gene expression patterns have not been described throughout vertebrate embryogenesis. This study presents statistical analyses of gene expression during all 40 developmental stages in the teleost Fundulus heteroclitus using four biological replicates per stage. Results Patterns of gene expression for 7,000 genes appear to be important as they recapitulate developmental timing. Among the 45% of genes with significant expression differences between pairs of temporally adjacent stages, significant differences in gene expression vary from as few as five to more than 660. Five adjacent stages have disproportionately more significant changes in gene expression (> 200 genes) relative to other stages: four to eight and eight to sixteen cell stages, onset of circulation, pre and post-hatch, and during complete yolk absorption. The fewest differences among adjacent stages occur during gastrulation. Yet, at stage 16, (pre-mid-gastrulation) the largest number of genes has peak expression. This stage has an over representation of genes in oxidative respiration and protein expression (ribosomes, translational genes and proteases). Unexpectedly, among all ribosomal genes, both strong positive and negative correlations occur. Similar correlated patterns of expression occur among all significant genes. Conclusions These data provide statistical support for the temporal dynamics of developmental gene expression during all stages of vertebrate development. PMID:21356103

  12. Embryogenesis of bladder exstrophy: A new hypothesis

    PubMed Central

    Kulkarni, Bharati; Chaudhari, Navin

    2008-01-01

    Aims and Objective: To postulate a hypothesis to explain the embryogenesis of exstrophy bladder based on our clinical observations. Materials and Methods: In 27 cases of exstrophy, we measured the distance between the lowermost inguinal skin crease to the root of the penis (clitoris) (B) and the distance between the penis (clitoris) and the scrotum (labia majora) (C). These were compared with age, height and XP distance (distance between xiphisternum and symphysis pubis) matched control group of normal children. The distance between the lowermost inguinal skin crease and the penis (clitoris) (A) was measured in control group. Results: The observation was A = B + C. This implies that in exstrophy bladder, the position of the penis (clitoris) has moved cephalad from the lower border of A to the junction of B and C. Conclusion: Based on the observations, we postulate that abnormal origin of genital tubercle may be the cause of exstrophy bladder. The abnormal origin of primordia of the genital tubercle in more cephalad direction than normal causes wedge effect, which will interfere with the medial migration of the mesoderm as well as the midline approximation of mesodermal structures in the lower abdominal wall, thereby resulting in the exstrophy of bladder. PMID:20011468

  13. Somatic Cell Dedifferentiation/Reprogramming for Regenerative Medicine

    PubMed Central

    Ramesh, Thiyagarajan; Lee, Sun-Hee; Lee, Choon-Soo; Kwon, Yoo-Wook; Cho, Hyun-Jai

    2009-01-01

    The concept of dedifferentiation or reprogramming of a somatic cell into a pluripotent embryonic stem cell-like cell (ES-like cell), which give rise to three germ layers and differentiate various cell types, opens a new era in stem cell biology and provides potential therapeutic modality in regenerative medicine. Here, we outline current dedifferentiation/reprogramming methods and their technical hurdles, and the safety and therapeutic applications of reprogrammed pluripotent stem cells in regenerative medicine. This review summarizes the concept and data of somatic cell nuclear transfer, fusion of somatic cells with ES cells, viral or non-viral transduction of pluripotency-related genes into somatic cells, introduction of extract (or proteins) of pluripotent cells into somatic cells. Dedifferentiated/reprogrammed ES-like cells could be a perfect genetic match (autologous or tailored pluripotent stem cells) for future applications. Further studies regarding technical refinements as well as mechanistic analysis of dedifferentiation induction and re-differentiation into specific cell types will provide us with the substantial application of pluripotent stem cells to therapeutic purposes. PMID:24855516

  14. 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

  15. 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.

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

    PubMed Central

    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. PMID:7460882

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

    PubMed Central

    Zúñiga, Alejandro; Hödar, Christian; Hanna, Patricia; Ibáñez, Freddy; Moreno, Pablo; Pulgar, Rodrigo; Pastenes, Luis; González, Mauricio; Cambiazo, Verónica

    2009-01-01

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

  18. Characterization of Somatically-Eliminated Genes During Development of the Sea Lamprey (Petromyzon marinus).

    PubMed

    Bryant, Stephanie A; Herdy, Joseph R; Amemiya, Chris T; Smith, Jeramiah J

    2016-09-01

    The sea lamprey (Petromyzon marinus) is a basal vertebrate that undergoes developmentally programmed genome rearrangements (PGRs) during early development. These events facilitate the elimination of ∼20% of the genome from the somatic cell lineage, resulting in distinct somatic and germline genomes. Thus far only a handful of germline-specific genes have been definitively identified within the estimated 500 Mb of DNA that is deleted during PGR, although a few thousand germline-specific genes are thought to exist. To improve our understanding of the evolutionary/developmental logic of PGR, we generated computational predictions to identify candidate germline-specific genes within a new transcriptomic dataset derived from adult germline and the early embryonic stages during which PGR occurs. Follow-up validation studies identified 44 germline-specific genes and further characterized patterns of transcription and DNA loss during early embryogenesis. Expression analyses reveal that many of these genes are differentially expressed during early embryogenesis and presumably function in the early development of the germline. Ontology analyses indicate that many of these germline-specific genes play known roles in germline development, pluripotency, and oncogenesis (when misexpressed). These studies provide support for the theory that PGR serves to segregate molecular functions related to germline development/pluripotency in order to prevent their potential misexpression in somatic cells. This larger set of eliminated genes also allows us to extend the evolutionary/developmental breadth of this theory, as some deleted genes (or their gnathostome homologs) appear to be associated with the early development of somatic lineages, perhaps through the evolution of novel functions within gnathostome lineages. PMID:27288344

  19. Function of retinoid nuclear receptors: lessons from genetic and pharmacological dissections of the retinoic acid signaling pathway during mouse embryogenesis.

    PubMed

    Mark, Manuel; Ghyselinck, Norbert B; Chambon, Pierre

    2006-01-01

    Retinoic acid (RA) is involved in vertebrate morphogenesis, growth, cellular differentiation, and tissue homeostasis. The use of in vitro systems initially led to the identification of nuclear receptor RXR/RAR heterodimers as possible transducers of the RA signal. To unveil the physiological functions of RARs and RXRs, genetic and pharmacological studies have been performed in the mouse. Together, their results demonstrate that (a) RXR/RAR heterodimers in which RXR is either transcriptionally active or silent are involved in the transduction of the RA signal during prenatal development, (b) specific RXRalpha/RAR heterodimers are required at many distinct stages during early embryogenesis and organogenesis, (c) the physiological role of RA and its receptors cannot be extrapolated from teratogenesis studies using retinoids in excess. Additional cell type-restricted and temporally controlled somatic mutagenesis is required to determine the functions of RARs and RXRs during postnatal life. PMID:16402912

  20. Vitellin processing and protein synthesis during cricket embryogenesis.

    PubMed

    Handley, H L; Estridge, B H; Bradley, J T

    1998-11-01

    At the start of insect embryogenesis most of the protein mass of the egg cytoplasm exists as vitellin (Vt) obtained endocytically during vitellogenesis. Of the new embryo polypeptides (EP) appearing in the egg during embryogenesis, many are synthesized de novo, while, in some species, others derive from developmentally programmed partial proteolysis of Vt. Earlier we showed that by the end of vitellogenesis the two native Vts in Acheta domesticus exist in opposing gradients along the longitudinal axis of the egg. Here we hypothesize that this ooplasmic Vt distribution presents a milieu for Vt processing out of which region-specific regulatory molecules could arise. The metabolic origin and stage-specific patterns of seven predominant EPs (EP 1-7) identified by SDS-PAGE were examined and the results correlated with developmental morphology during the 14 days of embryogenesis. Based on antibody reactivity, peptide mapping and in vitro radiolabeling, we determined that EPs 1-3, 6 and 7 are Vt-derived, while EPs 4 and 5 are produced de novo by the embryo. The five Vt-derived EPs appear during the first 24 h of embryogenesis when migrating cleavage nuclei and associated cytoplasm form the cellular blastoderm, and levels of EPs 4 and 5 increase during days 4-6 of embryogenesis when katatrepsis and yolk mass contraction occur. Positive periodic acid-Schiff staining indicated that EPs 1-3 and their Vt-precursor polypeptides are glycoproteins. This work shows that developmental stage-specific Vt processing occurs during A. domesticus embryogenesis and points next to investigation of the functional significance of Vt cleavage products during development. PMID:9818388

  1. 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

  2. Chimerism in humans after intragenic recombination at the haptoglobin locus during early embryogenesis.

    PubMed

    Asakawa, J; Kodaira, M; Nakamura, N; Satoh, C; Fujita, M

    1999-08-31

    The human haptoglobin (HP) HP*2 allele contains a 1.7-kilobase (kb) intragenic duplication that arose after a unique nonhomologous recombination between the prototype HP*1 alleles. During a genetic screening of 13,000 children of survivors exposed to atomic-bomb radiation and 10,000 children of unexposed persons, two children suspected of carrying de novo mutations at the haptoglobin locus were identified (one in each group). DNA analyses of single-cell-derived colonies of Epstein-Barr virus-transformed B cells revealed that the two children were mosaics comprising HP*2/HP*2 and HP*2/HP*1 cells at a ratio of approximately 3:1. We infer that the latter cells are caused by reversion of one HP*2 allele to HP*1 through an intramolecular homologous recombination between the duplicated segments of the Hp*2 allele that excised one of the segments. Because the mosaicism is substantial (approximately 25%), this recombination must have occurred in early embryogenesis. The frequency of finding these children and the extent of their mosaicisms corresponds to an HP*2 to HP*1 reversion rate of 8 x 10(-6) per cell during development. This leads to the prediction that the HP*1 allele also will be represented, although usually at a very low frequency, in any HP2-2 person. We tested this prediction by using PCR for a single individual and found the HP*1 allele at frequencies of 4 x 10(-6) and 3 x 10(-6) in somatic and sperm cells. The HP*1 allele was detected by PCR in all four other HP2-2 individuals, which supports the regular but rare occurrence somatically of homologous recombination within duplicated regions in humans, in agreement with previous observations in mouse and Drosophila. PMID:10468605

  3. 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.

  4. Physiological inputs regulate species-specific anatomy during embryogenesis and regeneration

    PubMed Central

    Sullivan, Kelly G.; Emmons-Bell, Maya; Levin, Michael

    2016-01-01

    ABSTRACT A key problem in evolutionary developmental biology is identifying the sources of instructive information that determine species-specific anatomical pattern. Understanding the inputs to large-scale morphology is also crucial for efforts to manipulate pattern formation in regenerative medicine and synthetic bioengineering. Recent studies have revealed a physiological system of communication among cells that regulates pattern during embryogenesis and regeneration in vertebrate and invertebrate models. Somatic tissues form networks using the same ion channels, electrical synapses, and neurotransmitter mechanisms exploited by the brain for information-processing. Experimental manipulation of these circuits was recently shown to override genome default patterning outcomes, resulting in head shapes resembling those of other species in planaria and Xenopus. The ability to drastically alter macroscopic anatomy to that of other extant species, despite a wild-type genomic sequence, suggests exciting new approaches to the understanding and control of patterning. Here, we review these results and discuss hypotheses regarding non-genomic systems of instructive information that determine biological growth and form. PMID:27574538

  5. Physiological inputs regulate species-specific anatomy during embryogenesis and regeneration.

    PubMed

    Sullivan, Kelly G; Emmons-Bell, Maya; Levin, Michael

    2016-01-01

    A key problem in evolutionary developmental biology is identifying the sources of instructive information that determine species-specific anatomical pattern. Understanding the inputs to large-scale morphology is also crucial for efforts to manipulate pattern formation in regenerative medicine and synthetic bioengineering. Recent studies have revealed a physiological system of communication among cells that regulates pattern during embryogenesis and regeneration in vertebrate and invertebrate models. Somatic tissues form networks using the same ion channels, electrical synapses, and neurotransmitter mechanisms exploited by the brain for information-processing. Experimental manipulation of these circuits was recently shown to override genome default patterning outcomes, resulting in head shapes resembling those of other species in planaria and Xenopus. The ability to drastically alter macroscopic anatomy to that of other extant species, despite a wild-type genomic sequence, suggests exciting new approaches to the understanding and control of patterning. Here, we review these results and discuss hypotheses regarding non-genomic systems of instructive information that determine biological growth and form. PMID:27574538

  6. Drosophila Embryogenesis Scales Uniformly across Temperature in Developmentally Diverse Species

    PubMed Central

    Kuntz, Steven G.; Eisen, Michael B.

    2014-01-01

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

  7. 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

  8. NO, ROS, and cell death associated with caspase-like activity increase in stress-induced microspore embryogenesis of barley

    PubMed Central

    Rodríguez-Serrano, María; Bárány, Ivett; Prem, Deepak; Coronado, María-José; Risueño, María C.; Testillano, Pilar S.

    2012-01-01

    Under specific stress treatments (cold, starvation), in vitro microspores can be induced to deviate from their gametophytic development and switch to embryogenesis, forming haploid embryos and homozygous breeding lines in a short period of time. The inductive stress produces reactive oxygen species (ROS) and nitric oxide (NO), signalling molecules mediating cellular responses, and cell death, modifying the embryogenic microspore response and therefore, the efficiency of the process. This work analysed cell death, caspase 3-like activity, and ROS and NO production (using fluorescence probes and confocal analysis) after inductive stress in barley microspore cultures and embryogenic suspension cultures, as an in vitro system which permitted easy handling for comparison. There was an increase in caspase 3-like activity and cell death after stress treatment in microspore and suspension cultures, while ROS increased in non-induced microspores and suspension cultures. Treatments of the cultures with a caspase 3 inhibitor, DEVD-CHO, significantly reduced the cell death percentages. Stress-treated embryogenic suspension cultures exhibited high NO signals and cell death, while treatment with S-nitrosoglutathione (NO donor) in control suspension cultures resulted in even higher cell death. In contrast, in microspore cultures, NO production was detected after stress, and, in the case of 4-day microspore cultures, in embryogenic microspores accompanying the initiation of cell divisions. Subsequent treatments of stress-treated microspore cultures with ROS and NO scavengers resulted in a decreasing cell death during the early stages, but later they produced a delay in embryo development as well as a decrease in the percentage of embryogenesis in microspores. Results showed that the ROS increase was involved in the stress-induced programmed cell death occurring at early stages in both non-induced microspores and embryogenic suspension cultures; whereas NO played a dual role after

  9. The effect of auxin type and concentration on pecan (Carya illinoinensis) somatic embryo morphology and subsequent conversion into plants.

    PubMed

    Rodriguez, A P; Wetzstein, H Y

    1994-08-01

    Embryogenic cultures were initiated from immature pecan zygotic embryos. Explants were induced for one week on Woody Plant Medium with either α-naphthaleneacetic acid or 2,4-dichlorophenoxyacetic acid at 2, 6 or 12 mg/l, then subcultured monthly to fresh basal medium. Observations were made on callus production, embryo formation, and embryo morphology. Somatic embryo morphology and overall callus proliferation were affected by auxin type. Callus proliferation was less extensive and more somatic embryos resembling zygotic embryos were obtained from cultures initiated with α-naphthaleneacetic acid than with 2,4-dichlorophenoxyacetic acid. Repetitive somatic embryogenesis was obtained in all auxin treatments. Conversion into plantlets was affected by somatic embryo morphology in that embryos with poorly developed apices exhibited lower percentages of conversion than those with well developed single or multiple apices. Consequently, although more embryos were obtained with 2,4-dichlorophenoxyacetic acid, naphthaleneacetic acid was the superior auxin for production of somatic embryos more likely to convert into plants. PMID:24196238

  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. Somatic Symptom and Related Disorders

    MedlinePlus

    ... and symptoms a person feels are related to psychological factors. These symptoms can't be traced to a specific physical cause. In people who have a somatic symptom and related disorder, medical test results are either normal or don't explain ...

  12. 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

  13. [Somatic trends in Moscow children].

    PubMed

    Fedotova, T K

    2008-01-01

    Somatic trends was considered in Moscow children in a wide age range of 3 to 17 years, by attracting several series of data since the 1990s. To have the greater informative value in data analyses, investigators use the normalized rather than absolute values of various anthropometric signs in the considered data series versus the 2005 data in the age range of 3 to 7 years and versus the 1980s data in the range of 8 to 17 years. The overall somatic tendency in Moscow children aged 3 to 17 years in past decades is towards a transverse body development and some dolichomorphism with a continuous increase in longitudinal skeletal sizes. These processes are most pronounced in girls than in boys and preschool children than in school ones. The stronger somatic trend in preschool children can be associated with that they are, as compared with schoolchildren, neophytes in the compact anthropogenic space and have been, in the past decades, involved in the neurogenic growth stimulators world (a computer and computer games, unlimited TV seeing, inevitable intensive preparation for new-generation schools--increased intellectual-load lyceums and colleges). The decreased transverse body development and overall constitution asthenization seem to result from somatic muscular component abatement with no clear trends in adipopexis in schoolchildren and with an increase in subcutaneous fat deposition in preschool children. PMID:18507175

  14. 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 η, pol κ and pol β 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

  15. 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

  16. 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.

  17. 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

  18. Morphogenesis of the somatic musculature in Drosophila melanogaster

    PubMed Central

    Schulman, Victoria K.; Dobi, Krista C.; Baylies, Mary K.

    2015-01-01

    In Drosophila melanogaster, the somatic muscle system is first formed during embryogenesis, giving rise to the larval musculature. Later during metamorphosis, this system is destroyed and replaced by an entirely new set of muscles in the adult fly. Proper formation of the larval and adult muscles is critical for basic survival functions such as hatching and crawling (in the larva), walking and flying (in the adult), and feeding (at both larval and adult stages). Myogenesis, from mononucleated muscle precursor cells to multinucleated functional muscles, is driven by a number of cellular processes that have begun to be mechanistically defined. Once themesodermal cells destined for themyogenic lineage have been specified, individual myoblasts fuse together iteratively to form syncytial myofibers. Combining cytoplasmic contents demands a level of intracellular reorganization that, most notably, leads to redistribution of the myonuclei to maximize internuclear distance. Signaling from extending myofibers induces terminal tendon cell differentiation in the ectoderm, which results in secure muscle-tendon attachments that are critical formuscle contraction. Simultaneously, muscles become innervated and undergo sarcomerogenesis to establish the contractile apparatus that will facilitate movement. The cellular mechanisms governing these morphogenetic events share numerous parallels to mammalian development, and the basic unit of all muscle, the myofiber, is conserved from flies to mammals. Thus, studies of Drosophila myogenesis and comparisons to muscle development in other systems highlight conserved regulatory programs of biomedical relevance to general muscle biology and studies of muscle disease. PMID:25758712

  19. DNA methylation dynamics and MET1a-like gene expression changes during stress-induced pollen reprogramming to embryogenesis

    PubMed Central

    Testillano, Pilar S.

    2012-01-01

    Stress-induced plant cell reprogramming involves changes in global genome organization, being the epigenetic modifications key factors in the regulation of genome flexibility. DNA methylation, accomplished by DNA methyltransferases, constitutes a prominent epigenetic modification of the chromatin fibre which is locked in a transcriptionally inactive conformation. Changes in DNA methylation accompany the reorganization of the nuclear architecture during plant cell differentiation and proliferation. After a stress treatment, in vitro-cultured microspores are reprogrammed and change their gametophytic developmental pathway towards embryogenesis, the process constituting a useful system of reprogramming in isolated cells for applied and basic research. Gene expression driven by developmental and stress cues often depends on DNA methylation; however, global DNA methylation and genome-wide expression patterns relationship is still poorly understood. In this work, the dynamics of DNA methylation patterns in relation to nuclear architecture and the expression of BnMET1a-like DNA methyltransferase genes have been analysed during pollen development and pollen reprogramming to embryogenesis in Brassica napus L. by a multidisciplinary approach. Results showed an epigenetic reprogramming after microspore embryogenesis induction which involved a decrease of global DNA methylation and its nuclear redistribution with the change of developmental programme and the activation of cell proliferation, while DNA methylation increases with pollen and embryo differentiation in a cell-type-specific manner. Changes in the presence, abundance, and distribution of BnMET1a-like transcripts highly correlated with variations in DNA methylation. Mature zygotic and pollen embryos presented analogous patterns of DNA methylation and MET1a-like expression, providing new evidence of the similarities between both developmental embryogenic programmes. PMID:23175669

  20. Labor Induction

    MedlinePlus

    ... QUESTIONS FAQ154 LABOR, DELIVERY, AND POSTPARTUM CARE Labor Induction • What is labor induction? • Why is labor induced? • What is the Bishop ... oxytocin? • What are the risks associated with labor induction? • Is labor induction always effective? • Glossary What is ...

  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. Attachment in romantic relationships and somatization.

    PubMed

    Neumann, Eva; Sattel, Heribert; Gündel, Harald; Henningsen, Peter; Kruse, Johannes

    2015-02-01

    Adult attachment representations have been considered to play a role in the development and treatment of somatizing behavior. In this study, the associations between the two attachment dimensions avoidance and anxiety and dimensions of psychopathology (somatization, depression, and general anxiety) were explored. The sample consists of 202 outpatients diagnosed with a somatoform disorder. Data were collected via self-report measures. A path analysis shows that the two attachment dimensions are not directly associated with somatization. There are, however, significant indirect associations between attachment and somatization mediated by depression and general anxiety, which are more pronounced for attachment anxiety than for attachment avoidance. The findings reveal that a low level of attachment security in romantic relationships, especially an anxious stance toward the partner, comes along with poor mental health, which in turn is related to a preoccupation with somatic complaints. Implications for the treatment of somatizing patients are discussed. PMID:25594785

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

    PubMed Central

    Yajima, Mamiko; Wessel, Gary M.

    2015-01-01

    ABSTRACT 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. 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.

  6. Immunological detection of potential signal-transduction proteins expressed during wheat somatic tissue culture.

    PubMed

    Nato, A; Mirshahi, A; Tichtinsky, G; Mirshahi, M; Faure, J P; Lavergne, D; De Buyser, J; Jean, C; Ducreux, G; Henry, Y

    1997-03-01

    An immunochemical approach was used to detect the expression of putative guanine nucleotide-binding proteins (G-proteins), arrestin, and nucleoside diphosphate kinases during wheat (Triticum aestivum) tissue culture initiated from immature embryos. Both the soluble and membrane extracts from the immature embryos revealed bands of 58, 40, and 16 kD with antibodies to G-protein (alpha subunit), arrestin, and nucleoside diphosphate kinase, respectively. These proteins were overexpressed in vitro in both nonembryogenic callus and embryogenic cultures. An additional soluble protein (32 kD) was detected by anti-G alpha antibodies in cultured tissues but not in immature embryos, suggesting a possible function in cell multiplication. Moreover, somatic embryogenesis was associated with the appearance of a 29-kD protein reactive with anti-arrstin antibodies, both in soluble and membrane fractions. Tissue-cultured genetic stocks of Chinese Spring wheat, including the disomic, 36 ditelosomic, and 6 nullisomic-tetrasomic wheat lines, were used to ascertain the chromosomal location of the genes encoding the 29-kD arrestin-like protein. The lack of a signal with the nonembryogenic ditelosomic 3 D short chromosome arm line suggests that the 3 D long chromosome arm possesses at least one gene involved in the expression of the 29-kD protein. The putative role of the 29-kD protein in signal-transduction regulating embryogenesis is discussed. PMID:9085574

  7. Immunological detection of potential signal-transduction proteins expressed during wheat somatic tissue culture.

    PubMed Central

    Nato, A; Mirshahi, A; Tichtinsky, G; Mirshahi, M; Faure, J P; Lavergne, D; De Buyser, J; Jean, C; Ducreux, G; Henry, Y

    1997-01-01

    An immunochemical approach was used to detect the expression of putative guanine nucleotide-binding proteins (G-proteins), arrestin, and nucleoside diphosphate kinases during wheat (Triticum aestivum) tissue culture initiated from immature embryos. Both the soluble and membrane extracts from the immature embryos revealed bands of 58, 40, and 16 kD with antibodies to G-protein (alpha subunit), arrestin, and nucleoside diphosphate kinase, respectively. These proteins were overexpressed in vitro in both nonembryogenic callus and embryogenic cultures. An additional soluble protein (32 kD) was detected by anti-G alpha antibodies in cultured tissues but not in immature embryos, suggesting a possible function in cell multiplication. Moreover, somatic embryogenesis was associated with the appearance of a 29-kD protein reactive with anti-arrstin antibodies, both in soluble and membrane fractions. Tissue-cultured genetic stocks of Chinese Spring wheat, including the disomic, 36 ditelosomic, and 6 nullisomic-tetrasomic wheat lines, were used to ascertain the chromosomal location of the genes encoding the 29-kD arrestin-like protein. The lack of a signal with the nonembryogenic ditelosomic 3 D short chromosome arm line suggests that the 3 D long chromosome arm possesses at least one gene involved in the expression of the 29-kD protein. The putative role of the 29-kD protein in signal-transduction regulating embryogenesis is discussed. PMID:9085574

  8. 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.

  9. 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

  10. Regulation of germ layer formation by pluripotency factors during embryogenesis

    PubMed Central

    2013-01-01

    The classical pluripotency factors Oct4, Klf4, Sox2, and Nanog are required for the maintenance of pluripotency and self-renewal of embryonic stem (ES) cells and can reprogram terminally differentiated cells into a pluripotent state. Alteration in the levels of these factors in ES cells will cause differentiation into different lineages, suggesting that they are critical determinants of cell fates. These factors show dynamic expression patterns during embryogenesis, in particular in the pluripotent or multipotent cells of an early stage embryo, implying that they are involved in the cell fate decision during early embryonic development. Functions and the underlying molecular mechanisms have been extensively studied for these factors in ES cells under cultured conditions. However, this does not mean that the results also hold true for intact embryos. In the review, I have summarized and discussed the findings on the functions and the underlying mechanisms of the classical pluripotency factors during early embryogenesis, in particular during germ layer formation. PMID:23497659

  11. Autophagy and apoptosis are redundantly required for C. elegans embryogenesis.

    PubMed

    Borsos, Eva; Erdélyi, Péter; Vellai, Tibor

    2011-05-01

    Apoptosis, the main form of regulated (or programmed) cell death, allows the organism to tightly control cell numbers and tissue size, and to protect itself from potentially damaging cells. This type of cellular self-killing has long been assumed to be essential for early development. In the nematode Caenorhabditis elegans, however, the core apoptotic cell death pathway appears to be dispensable for embryogenesis when most developmental cell deaths take place: mutant nematodes defective for apoptosis develop into adulthood, with superficially normal morphology and behavior. Accumulating evidence indicates a similar situation in mammalian systems as well. For example, apoptosis-deficient mice can grow as healthy, fertile adults. These observations raise the possibility that alternative cell death mechanisms may compensate for the lack of apoptotic machinery in developing embryos. Interestingly, C. elegans embryogenesis can also occur without autophagy, an alternative form of cellular self-destruction (also called autophagic cell death). In an upcoming paper we report that simultaneous inactivation of the autophagic and apoptotic gene cascades in C. elegans arrests development at early stages, and the affected embryos exhibit severe morphological defects. Double-mutant nematode embryos deficient in both autophagy and apoptosis are unable to undergo body elongation or to arrange several tissues correctly. This novel function of autophagy genes in morphogenesis indicates a more fundamental role for cellular self-digestion in tissue patterning than previously thought. PMID:21285529

  12. Systematic determination of patterns of gene expression during Drosophila embryogenesis

    PubMed Central

    Tomancak, Pavel; Beaton, Amy; Weiszmann, Richard; Kwan, Elaine; Shu, ShengQiang; Lewis, Suzanna E; Richards, Stephen; Ashburner, Michael; Hartenstein, Volker; Celniker, Susan E; Rubin, Gerald M

    2002-01-01

    Background Cell-fate specification and tissue differentiation during development are largely achieved by the regulation of gene transcription. Results As a first step to creating a comprehensive atlas of gene-expression patterns during Drosophila embryogenesis, we examined 2,179 genes by in situ hybridization to fixed Drosophila embryos. Of the genes assayed, 63.7% displayed dynamic expression patterns that were documented with 25,690 digital photomicrographs of individual embryos. The photomicrographs were annotated using controlled vocabularies for anatomical structures that are organized into a developmental hierarchy. We also generated a detailed time course of gene expression during embryogenesis using microarrays to provide an independent corroboration of the in situ hybridization results. All image, annotation and microarray data are stored in publicly available database. We found that the RNA transcripts of about 1% of genes show clear subcellular localization. Nearly all the annotated expression patterns are distinct. We present an approach for organizing the data by hierarchical clustering of annotation terms that allows us to group tissues that express similar sets of genes as well as genes displaying similar expression patterns. Conclusions Analyzing gene-expression patterns by in situ hybridization to whole-mount embryos provides an extremely rich dataset that can be used to identify genes involved in developmental processes that have been missed by traditional genetic analysis. Systematic analysis of rigorously annotated patterns of gene expression will complement and extend the types of analyses carried out using expression microarrays. PMID:12537577

  13. 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

  14. Depression, Life Events and Somatic Symptoms.

    ERIC Educational Resources Information Center

    Rozzini, Renzo; And Others

    1988-01-01

    Investigated the relationship between somatic symptoms, depression, and life events (health status, function, social satisfaction, income) in a population of 1,201 elderly persons living at home. Found depression was the most important factor in the appearance of somatic complaints; however, life events were important cofactors in defining…

  15. 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

  16. Somatic Cell Counts in Bovine Milk

    PubMed Central

    Dohoo, I. R.; Meek, A. H.

    1982-01-01

    Factors which influence somatic cell counts in bovine milk are reviewed and guidelines for their interpretation are presented. It is suggested that the thresholds of 300 000 and 250 000 cells/mL be used to identify infected quarters and cows respectively. However, it is stressed that somatic cell counts are general indicators of udder health which are subject to the influence of many factors. Therefore the evaluation of several successive counts is preferable to the interpretation of an individual count. Relationships between somatic cell counts and both milk production and milk composition are discussed. Subclinical mastitis reduces milk quality and decreases yield although the relationship between production loss and somatic cell count requires clarification. Finally the availability of somatic cell counting programs in Canada is presented. PMID:17422127

  17. Early-stage epigenetic modification during somatic cell reprogramming by Parp1 and Tet2.

    PubMed

    Doege, Claudia A; Inoue, Keiichi; Yamashita, Toru; Rhee, David B; Travis, Skylar; Fujita, Ryousuke; Guarnieri, Paolo; Bhagat, Govind; Vanti, William B; Shih, Alan; Levine, Ross L; Nik, Sara; Chen, Emily I; Abeliovich, Asa

    2012-08-30

    Somatic cells can be reprogrammed into induced pluripotent stem cells (iPSCs) by using the pluripotency factors Oct4, Sox2, Klf4 and c-Myc (together referred to as OSKM). iPSC reprogramming erases somatic epigenetic signatures—as typified by DNA methylation or histone modification at silent pluripotency loci—and establishes alternative epigenetic marks of embryonic stem cells (ESCs). Here we describe an early and essential stage of somatic cell reprogramming, preceding the induction of transcription at endogenous pluripotency loci such as Nanog and Esrrb. By day 4 after transduction with OSKM, two epigenetic modification factors necessary for iPSC generation, namely poly(ADP-ribose) polymerase-1 (Parp1) and ten-eleven translocation-2 (Tet2), are recruited to the Nanog and Esrrb loci. These epigenetic modification factors seem to have complementary roles in the establishment of early epigenetic marks during somatic cell reprogramming: Parp1 functions in the regulation of 5-methylcytosine (5mC) modification, whereas Tet2 is essential for the early generation of 5-hydroxymethylcytosine (5hmC) by the oxidation of 5mC (refs 3,4). Although 5hmC has been proposed to serve primarily as an intermediate in 5mC demethylation to cytosine in certain contexts, our data, and also studies of Tet2-mutant human tumour cells, argue in favour of a role for 5hmC as an epigenetic mark distinct from 5mC. Consistent with this, Parp1 and Tet2 are each needed for the early establishment of histone modifications that typify an activated chromatin state at pluripotency loci, whereas Parp1 induction further promotes accessibility to the Oct4 reprogramming factor. These findings suggest that Parp1 and Tet2 contribute to an epigenetic program that directs subsequent transcriptional induction at pluripotency loci during somatic cell reprogramming. PMID:22902501

  18. Hypothesis: Somatic Mosaicism and Parkinson Disease

    PubMed Central

    Kim, Han-Joon

    2014-01-01

    Mutations causing genetic disorders can occur during mitotic cell division after fertilization, which is called somatic mutations. This leads to somatic mosaicism, where two or more genetically distinct cells are present in one individual. Somatic mutations are the most well studied in cancer where it plays an important role and also have been associated with some neurodegenerative disorders. The study of somatic mosaicism in Parkinson disease (PD) is only in its infancy, and a case with somatic mutation has not yet been described. However, we can speculate that a somatic mutation affecting cells in the central nervous system including substantia nigra dopaminergic neurons could lead to the development of PD through the same pathomechanisms of genetic PD even in the absence of a germ-line mutation. Theoretically, a number of genes could be candidates for genetic analysis for the presence of somatic mosaicism. Among them, SNCA and PARK2 could be the best candidates to analyze. Because analyzing brain tissues in living patients is impossible, alternative tissues could be used to indicate the genetic status of the brain. Performance of the technology is another factor to consider when analyzing the tissues. PMID:25548528

  19. 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

  20. Developmental regulation of Tbx5 in zebrafish embryogenesis.

    PubMed

    Begemann, G; Ingham, P W

    2000-02-01

    T-box (tbx) genes constitute a large family of transcriptional regulators involved in developmental patterning processes. In tetrapods, tbx5 has been implicated in specifying forelimb type identity. Here, we report the cloning of the zebrafish tbx5.1 gene and characterise its expression during zebrafish embryogenesis and early larval development of wild type and mutant embryos that affect pectoral fin patterning. tbx5.1 is expressed during development of the heart, the pectoral fins and the eye. Notably, its expression in the lateral plate mesoderm defines a single and continuous region of heart and pectoral fin precursor cells, and constitutes the earliest specific marker for pectoral fin development in the zebrafish. PMID:10640716

  1. 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

  2. Current insights into hormonal regulation of microspore embryogenesis

    PubMed Central

    Żur, 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

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

    PubMed

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

    2016-04-01

    Embryogenesis in rice is different from that of most dicotolydonous plants in that it shows a non-stereotypic cell division pattern, formation of dorsal-ventral polarity, and endogenous initiation of the radicle. To reveal the transcriptional features associated with developmental events during rice early embryogenesis, we used microarray analysis coupled with laser microdissection to obtain both spatial and temporal transcription profiles. Our results allowed us to determine spatial expression foci for each expressed gene in the globular embryo, which revealed the importance of phytohormone-related genes and a suite of transcription factors to early embryogenesis. Our analysis showed the polarized expression of a small number of genes along the apical-basal and dorsal-ventral axes in the globular embryo, which tended to fluctuate in later developmental stages. We also analyzed gene expression patterns in the early globular embryo and how this relates to expression in embryonic organs at later stages. We confirmed the accuracy of the expression patterns found by microarray analysis of embryo subdomains usingin situhybridization. Our study identified homologous genes fromArabidopsis thalianawith known functions in embryogenesis in addition to unique and uncharacterized genes that show polarized expression patterns during embryogenesis. The results of this study are presented in a database to provide a framework for spatiotemporal gene expression during rice embryogenesis, to serve as a resource for future functional analysis of genes, and as a basis for comparative studies of plant embryogenesis. PMID:26903508

  4. 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

  5. Dynamic Nucleosome Organization at hox Promoters during Zebrafish Embryogenesis

    PubMed Central

    Weicksel, Steven E.; Xu, Jia; Sagerström, Charles G.

    2013-01-01

    Nucleosome organization at promoter regions plays an important role in regulating gene activity. Genome-wide studies in yeast, flies, worms, mammalian embryonic stem cells and transformed cell lines have found well-positioned nucleosomes flanking a nucleosome depleted region (NDR) at transcription start sites. This nucleosome arrangement depends on DNA sequence (cis-elements) as well as DNA binding factors and ATP-dependent chromatin modifiers (trans-factors). However, little is understood about how the nascent embryonic genome positions nucleosomes during development. This is particularly intriguing since the embryonic genome must undergo a broad reprogramming event upon fusion of sperm and oocyte. Using four stages of early embryonic zebrafish development, we map nucleosome positions at the promoter region of 37 zebrafish hox genes. We find that nucleosome arrangement at the hox promoters is a progressive process that takes place over several stages. At stages immediately after fertilization, nucleosomes appear to be largely disordered at hox promoter regions. At stages after activation of the embryonic genome, nucleosomes are detectable at hox promoters, with positions becoming more uniform and more highly occupied. Since the genomic sequence is invariant during embryogenesis, this progressive change in nucleosome arrangement suggests that trans-factors play an important role in organizing nucleosomes during embryogenesis. Separating hox genes into expressed and non-expressed groups shows that expressed promoters have better positioned and occupied nucleosomes, as well as distinct NDRs, than non-expressed promoters. Finally, by blocking the retinoic acid-signaling pathway, we disrupt early hox gene transcription, but observe no effect on nucleosome positions, suggesting that active hox transcription is not a driving force behind the arrangement of nucleosomes at the promoters of hox genes during early development. PMID:23671670

  6. [Somatization disorder - an overdiagnosed but underestimated illness].

    PubMed

    Karvonen, Juha T; Läksy, Kristian; Räsänen, Sami

    2016-01-01

    Physical symptoms often occur in the absence of physical illness. This is termed somatization when the symptoms are caused by psychic factors. When abundant symptoms affect the functional capacity and cause subjective harm and seeking healthcare services, a psychic disorder may be in question. Somatization may be associated with numerous psychic disorders. It may, however, also be a question of a somatoform disorder having a physical symptom picture. Somatization disorder is one of the somatoform disorders. Recognition of the disorder is often the problem in its treatment. Establishing a long-term treatment relationship actually forms the basis for therapy. PMID:26951025

  7. Regulation of somatic cell reprogramming through inducible mir-302 expression.

    PubMed

    Lin, Shi-Lung; Chang, Donald C; Lin, Chun-Hung; Ying, Shao-Yao; Leu, Davey; Wu, David T S

    2011-02-01

    Global demethylation is required for early zygote development to establish stem cell pluripotency, yet our findings reiterate this epigenetic reprogramming event in somatic cells through ectopic introduction of mir-302 function. Here, we report that induced mir-302 expression beyond 1.3-fold of the concentration in human embryonic stem (hES) H1 and H9 cells led to reprogramming of human hair follicle cells (hHFCs) to induced pluripotent stem (iPS) cells. This reprogramming mechanism functioned through mir-302-targeted co-suppression of four epigenetic regulators, AOF2 (also known as KDM1 or LSD1), AOF1, MECP1-p66 and MECP2. Silencing AOF2 also caused DNMT1 deficiency and further enhanced global demethylation during somatic cell reprogramming (SCR) of hHFCs. Re-supplementing AOF2 in iPS cells disrupted such global demethylation and induced cell differentiation. Given that both hES and iPS cells highly express mir-302, our findings suggest a novel link between zygotic reprogramming and SCR, providing a regulatory mechanism responsible for global demethylation in both events. As the mechanism of conventional iPS cell induction methods remains largely unknown, understanding this microRNA (miRNA)-mediated SCR mechanism may shed light on the improvements of iPS cell generation. PMID:20870751

  8. 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

  9. Pilates, Mindfulness and Somatic Education

    PubMed Central

    Caldwell, Karen; Quin, Rebecca; Harrison, Mandy; Greeson, Jeffrey

    2014-01-01

    The Pilates Method is a form of somatic education with the potential to cultivate mindfulness – a mental quality associated with overall well-being. However, controlled studies are needed to determine whether changes in mindfulness are specific to the Pilates Method or also result from other forms of exercise. This quasi-experimental study compared Pilates Method mat classes and recreational exercise classes on measures of mindfulness and well-being at the beginning, middle and end of a 15 week semester. Total mindfulness scores increased overall for the Pilates Method group but not for the exercise control group, and these increases were directly related to end of semester ratings of self-regulatory self-efficacy, perceived stress and mood. Findings suggest that the Pilates Method specifically enhances mindfulness, and these increases are associated with other measures of wellness. The changes in mindfulness identified in this study support the role of the Pilates Method in the mental well-being of its practitioners and its potential to support dancers’ overall well-being. PMID:25328542

  10. Pilates, Mindfulness and Somatic Education.

    PubMed

    Caldwell, Karen; Adams, Marianne; Quin, Rebecca; Harrison, Mandy; Greeson, Jeffrey

    2013-12-01

    The Pilates Method is a form of somatic education with the potential to cultivate mindfulness - a mental quality associated with overall well-being. However, controlled studies are needed to determine whether changes in mindfulness are specific to the Pilates Method or also result from other forms of exercise. This quasi-experimental study compared Pilates Method mat classes and recreational exercise classes on measures of mindfulness and well-being at the beginning, middle and end of a 15 week semester. Total mindfulness scores increased overall for the Pilates Method group but not for the exercise control group, and these increases were directly related to end of semester ratings of self-regulatory self-efficacy, perceived stress and mood. Findings suggest that the Pilates Method specifically enhances mindfulness, and these increases are associated with other measures of wellness. The changes in mindfulness identified in this study support the role of the Pilates Method in the mental well-being of its practitioners and its potential to support dancers' overall well-being. PMID:25328542

  11. Processed pseudogenes acquired somatically during cancer development.

    PubMed

    Cooke, Susanna L; Shlien, Adam; Marshall, John; Pipinikas, Christodoulos P; Martincorena, Inigo; Tubio, Jose M C; Li, Yilong; Menzies, Andrew; Mudie, Laura; Ramakrishna, Manasa; Yates, Lucy; Davies, Helen; Bolli, Niccolo; Bignell, Graham R; Tarpey, Patrick S; Behjati, Sam; Nik-Zainal, Serena; Papaemmanuil, Elli; Teixeira, Vitor H; Raine, Keiran; O'Meara, Sarah; Dodoran, Maryam S; Teague, Jon W; Butler, Adam P; Iacobuzio-Donahue, Christine; Santarius, Thomas; Grundy, Richard G; Malkin, David; Greaves, Mel; Munshi, Nikhil; Flanagan, Adrienne M; Bowtell, David; Martin, Sancha; Larsimont, Denis; Reis-Filho, Jorge S; Boussioutas, Alex; Taylor, Jack A; Hayes, Neil D; Janes, Sam M; Futreal, P Andrew; Stratton, Michael R; McDermott, Ultan; Campbell, Peter J

    2014-01-01

    Cancer evolves by mutation, with somatic reactivation of retrotransposons being one such mutational process. Germline retrotransposition can cause processed pseudogenes, but whether this occurs somatically has not been evaluated. Here we screen sequencing data from 660 cancer samples for somatically acquired pseudogenes. We find 42 events in 17 samples, especially non-small cell lung cancer (5/27) and colorectal cancer (2/11). Genomic features mirror those of germline LINE element retrotranspositions, with frequent target-site duplications (67%), consensus TTTTAA sites at insertion points, inverted rearrangements (21%), 5' truncation (74%) and polyA tails (88%). Transcriptional consequences include expression of pseudogenes from UTRs or introns of target genes. In addition, a somatic pseudogene that integrated into the promoter and first exon of the tumour suppressor gene, MGA, abrogated expression from that allele. Thus, formation of processed pseudogenes represents a new class of mutation occurring during cancer development, with potentially diverse functional consequences depending on genomic context. PMID:24714652

  12. Processed pseudogenes acquired somatically during cancer development

    PubMed Central

    Cooke, Susanna L.; Shlien, Adam; Marshall, John; Pipinikas, Christodoulos P.; Martincorena, Inigo; Tubio, Jose M.C.; Li, Yilong; Menzies, Andrew; Mudie, Laura; Ramakrishna, Manasa; Yates, Lucy; Davies, Helen; Bolli, Niccolo; Bignell, Graham R.; Tarpey, Patrick S.; Behjati, Sam; Nik-Zainal, Serena; Papaemmanuil, Elli; Teixeira, Vitor H.; Raine, Keiran; O’Meara, Sarah; Dodoran, Maryam S.; Teague, Jon W.; Butler, Adam P.; Iacobuzio-Donahue, Christine; Santarius, Thomas; Grundy, Richard G.; Malkin, David; Greaves, Mel; Munshi, Nikhil; Flanagan, Adrienne M.; Bowtell, David; Martin, Sancha; Larsimont, Denis; Reis-Filho, Jorge S.; Boussioutas, Alex; Taylor, Jack A.; Hayes, Neil D.; Janes, Sam M.; Futreal, P. Andrew; Stratton, Michael R.; McDermott, Ultan; Campbell, Peter J.; Provenzano, Elena; van de Vijver, Marc; Richardson, Andrea L.; Purdie, Colin; Pinder, Sarah; Mac Grogan, Gaetan; Vincent-Salomon, Anne; Larsimont, Denis; Grabau, Dorthe; Sauer, Torill; Garred, Øystein; Ehinger, Anna; Van den Eynden, Gert G.; van Deurzen, C.H.M; Salgado, Roberto; Brock, Jane E.; Lakhani, Sunil R.; Giri, Dilip D.; Arnould, Laurent; Jacquemier, Jocelyne; Treilleux, Isabelle; Caldas, Carlos; Chin, Suet-Feung; Fatima, Aquila; Thompson, Alastair M.; Stenhouse, Alasdair; Foekens, John; Martens, John; Sieuwerts, Anieta; Brinkman, Arjen; Stunnenberg, Henk; Span, Paul N.; Sweep, Fred; Desmedt, Christine; Sotiriou, Christos; Thomas, Gilles; Broeks, Annegein; Langerod, Anita; Aparicio, Samuel; Simpson, Peter T.; van ’t Veer, Laura; Erla Eyfjörd, Jórunn; Hilmarsdottir, Holmfridur; Jonasson, Jon G.; Børresen-Dale, Anne-Lise; Lee, Ming Ta Michael; Wong, Bernice Huimin; Tan, Benita Kiat Tee; Hooijer, Gerrit K.J.

    2014-01-01

    Cancer evolves by mutation, with somatic reactivation of retrotransposons being one such mutational process. Germline retrotransposition can cause processed pseudogenes, but whether this occurs somatically has not been evaluated. Here we screen sequencing data from 660 cancer samples for somatically acquired pseudogenes. We find 42 events in 17 samples, especially non-small cell lung cancer (5/27) and colorectal cancer (2/11). Genomic features mirror those of germline LINE element retrotranspositions, with frequent target-site duplications (67%), consensus TTTTAA sites at insertion points, inverted rearrangements (21%), 5′ truncation (74%) and polyA tails (88%). Transcriptional consequences include expression of pseudogenes from UTRs or introns of target genes. In addition, a somatic pseudogene that integrated into the promoter and first exon of the tumour suppressor gene, MGA, abrogated expression from that allele. Thus, formation of processed pseudogenes represents a new class of mutation occurring during cancer development, with potentially diverse functional consequences depending on genomic context. PMID:24714652

  13. Stress and Somatic Complaints in Low-Income Urban Adolescents.

    ERIC Educational Resources Information Center

    Reynolds, Linda K.; O'Koon, Jeffrey H.; Papademetriou, Eros; Szczygiel, Sylvia; Grant, Kathryn E.

    2001-01-01

    Studied rates of somatic complaints and the association between stress and somatic complaints for 1,030 low-income urban adolescents in grades 6 through 8. For both boys and girls, somatization was the most commonly reported internalizing symptom, and heightened rates of urban stress predicted heightened rates of somatic complaints. (SLD)

  14. (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.

  15. Multicellularity makes somatic differentiation evolutionarily stable

    PubMed Central

    Wahl, Mary E.; Murray, Andrew W.

    2016-01-01

    Many multicellular organisms produce two cell lineages: germ cells, whose descendants produce the next generation, and somatic cells, which support, protect, and disperse the germ cells. This germ-soma demarcation has evolved independently in dozens of multicellular taxa but is absent in unicellular species. A common explanation holds that in these organisms, inefficient intercellular nutrient exchange compels the fitness cost of producing nonreproductive somatic cells to outweigh any potential benefits. We propose instead that the absence of unicellular, soma-producing populations reflects their susceptibility to invasion by nondifferentiating mutants that ultimately eradicate the soma-producing lineage. We argue that multicellularity can prevent the victory of such mutants by giving germ cells preferential access to the benefits conferred by somatic cells. The absence of natural unicellular, soma-producing species previously prevented these hypotheses from being directly tested in vivo: to overcome this obstacle, we engineered strains of the budding yeast Saccharomyces cerevisiae that differ only in the presence or absence of multicellularity and somatic differentiation, permitting direct comparisons between organisms with different lifestyles. Our strains implement the essential features of irreversible conversion from germ line to soma, reproductive division of labor, and clonal multicellularity while maintaining sufficient generality to permit broad extension of our conclusions. Our somatic cells can provide fitness benefits that exceed the reproductive costs of their production, even in unicellular strains. We find that nondifferentiating mutants overtake unicellular populations but are outcompeted by multicellular, soma-producing strains, suggesting that multicellularity confers evolutionary stability to somatic differentiation. PMID:27402737

  16. Multicellularity makes somatic differentiation evolutionarily stable.

    PubMed

    Wahl, Mary E; Murray, Andrew W

    2016-07-26

    Many multicellular organisms produce two cell lineages: germ cells, whose descendants produce the next generation, and somatic cells, which support, protect, and disperse the germ cells. This germ-soma demarcation has evolved independently in dozens of multicellular taxa but is absent in unicellular species. A common explanation holds that in these organisms, inefficient intercellular nutrient exchange compels the fitness cost of producing nonreproductive somatic cells to outweigh any potential benefits. We propose instead that the absence of unicellular, soma-producing populations reflects their susceptibility to invasion by nondifferentiating mutants that ultimately eradicate the soma-producing lineage. We argue that multicellularity can prevent the victory of such mutants by giving germ cells preferential access to the benefits conferred by somatic cells. The absence of natural unicellular, soma-producing species previously prevented these hypotheses from being directly tested in vivo: to overcome this obstacle, we engineered strains of the budding yeast Saccharomyces cerevisiae that differ only in the presence or absence of multicellularity and somatic differentiation, permitting direct comparisons between organisms with different lifestyles. Our strains implement the essential features of irreversible conversion from germ line to soma, reproductive division of labor, and clonal multicellularity while maintaining sufficient generality to permit broad extension of our conclusions. Our somatic cells can provide fitness benefits that exceed the reproductive costs of their production, even in unicellular strains. We find that nondifferentiating mutants overtake unicellular populations but are outcompeted by multicellular, soma-producing strains, suggesting that multicellularity confers evolutionary stability to somatic differentiation. PMID:27402737

  17. Microspore embryogenesis and programmed cell death in barley: effects of copper on albinism in recalcitrant cultivars.

    PubMed

    Jacquard, Cédric; Nolin, Frédérique; Hécart, Carine; Grauda, Dace; Rashal, Isaak; Dhondt-Cordelier, Sandrine; Sangwan, Rajbir S; Devaux, Pierre; Mazeyrat-Gourbeyre, Florence; Clément, Christophe

    2009-09-01

    Albinism remains a major problem in cereal improvement programs that rely on doubled haploid (DH) technology, and the factors controlling the phenomenon are not well understood. Here we report on the positive influence of copper on the production of DH plants obtained through microspore embryogenesis (ME) in recalcitrant cultivars of barley (Hordeum vulgare L.). The presence of copper sulphate in the anther pre-treatment medium improved green DH plant regeneration from cultivars known to produce exclusively albino plants using classical procedures. In plastids, the effect of copper was characterized by a decrease in starch and a parallel increase in internal membranes. The addition of copper sulphate in the ME pre-treatment medium should enable breeders to exploit the genetic diversity of recalcitrant cultivars through DH technology. We examined programmed cell death (PCD) during microspore development to determine whether PCD may interfere with the induction of ME and/or the occurrence of albinism. By examining the fate of nuclei in various anther cell layers, we demonstrated that the kinetics of PCD in anthers differed between the barley cultivars Igri and Cork that show a low and a high rate of albinism, respectively. However, no direct correlation between PCD in the anther cell layers and the rate of albinism was observed and copper had no influence on the PCD kinetic in these cultivars. It was concluded that albinism following ME was not due to PCD in anthers, but rather to another unknown phenomenon that appears to specifically affect plastids during microspore/pollen development. PMID:19529940

  18. Protocols for Obtaining Zygotic and Somatic Embryos for Studying the Regulation of Early Embryo Development in the Model Legume Medicago truncatula.

    PubMed

    Kurdyukov, Sergey; Song, Youhong; Tiew, Terence W-Y; Wang, Xin-Ding; Nolan, Kim E; Rose, Ray J

    2015-01-01

    Early embryogenesis starting from a single cell zygote goes through rapid cell division and morphogenesis, and is morphologically characterized by pre-globular, globular, heart, torpedo and cotyledon stages. This progressive development is under the tight regulation of a complex molecular network. Harvesting sufficient early embryos at a similar stage of development is essential for investigating the cellular and molecular regulation of early embryogenesis. This is not straightforward since early embryogenesis undergoes rapid morphogenesis in a short while e.g. 8 days for Medicago truncatula to reach the early cotyledon stage. Here, we address the issue by two approaches. The first one establishes a linkage between embryo development and pod morphology in helping indicate the stage of the zygotic embryo. This is particularly based on the number of pod spirals and development of the spines. An alternative way to complement the in vivo studies is via culturing leaf explants to produce somatic embryos. The medium includes an unusual hormone combination - an auxin (1-naphthaleneacetic acid), a cytokinin (6-benzylaminopurine), abscisic acid and gibberellic acid. The different stages can be discerned growing out of the callus without dissection. PMID:26131626

  19. Somatic presentation of psychiatric morbidity in general practice.

    PubMed Central

    Weich, S; Lewis, G; Donmall, R; Mann, A

    1995-01-01

    BACKGROUND. Twenty per cent of new illnesses in general practice, and 3% of consecutive attenders, are incident cases of 'pure' somatization. AIM. This study set out to estimate the prevalence of consultations by patients with psychiatric morbidity who present only somatic symptoms (somatic presentation), and to compare this with the likely prevalence of pure somatization. METHOD. A cross-sectional survey of consecutive general practice attenders was carried out. Psychiatric morbidity was measured using the general health questionnaire. Pure somatization was defined as medical consultation for somatic symptoms that were judged by a psychiatrist during an interview to be aetiologically attributable to an underlying psychiatric disorder but which were not recognized as such by the patient. RESULTS. Of attenders 25% were identified as somatic presenters. Of the somatic presenters interviewed one in six were estimated to be pure somatizers, which would extrapolate to 4% of attenders. Though all somatic presenters were probable cases of psychiatric disorder, subjects in this group had lower scores on the general health questionnaire than those who presented with psychological symptoms. General practitioner recognition of psychiatric morbidity was significantly lower among somatic presenters than for other subjects with psychiatric morbidity. CONCLUSION. General practitioner recognition of psychiatric morbidity could be improved for all types of somatic presentation, regardless of the aetiology of patients' somatic symptoms. There is a danger that concentrating attention on pure somatization may mean that psychiatric morbidity in the more common undifferentiated form of somatic presentation will be overlooked. PMID:7772392

  20. Effect of light conditions on anatomical and biochemical aspects of somatic and zygotic embryos of hybrid larch (Larix × marschlinsii)

    PubMed Central

    von Aderkas, Patrick; Teyssier, Caroline; Charpentier, Jean-Paul; Gutmann, Markus; Pâques, Luc; Le Metté, Claire; Ader, Kevin; Label, Philippe; Kong, Lisheng; Lelu-Walter, Marie-Anne

    2015-01-01

    Background and Aims In conifers, mature somatic embryos and zygotic embryos appear to resemble one another physiologically and morphologically. However, phenotypes of cloned conifer embryos can be strongly influenced by a number of in vitro factors and in some instances clonal variation can exceed that found in nature. This study examines whether zygotic embryos that develop within light-opaque cones differ from somatic embryos developing in dark/light conditions in vitro. Embryogenesis in larch is well understood both in situ and in vitro and thus provides a suitable system for addressing this question. Methods Features of somatic and zygotic embryos of hybrid larch, Larix × marschlinsii, were quantified, including cotyledon numbers, protein concentration and phenol chemistry. Somatic embryos were placed either in light or darkness for the entire maturation period. Embryos at different developmental stages were embedded and sectioned for histological analysis. Key Results Light, and to a lesser degree abscisic acid (ABA), influenced accumulation of protein and phenolic compounds in somatic and zygotic embryos. Dark-grown mature somatic embryos had more protein (91·77 ± 11·26 µg protein mg–1 f.wt) than either dark-grown zygotic embryos (62·40 ± 5·58) or light-grown somatic embryos (58·15 ± 10·02). Zygotic embryos never accumulated phenolic compounds at any stage, whereas somatic embryos stored phenolic compounds in the embryonal root caps and suspensors. Light induced the production of quercetrin (261·13 ± 9·2 µg g–1 d.wt) in somatic embryos. Mature zygotic embryos that were removed from seeds and placed on medium in light rapidly accumulated phenolics in the embryonal root cap and hypocotyl. Delaying germination with ABA delayed phenolic compound accumulation, restricting it to the embryonal root cap. Conclusions In larch embryos, light has a negative effect on protein accumulation, but a positive effect on phenol

  1. Induction voidmeter

    DOEpatents

    Anderson, Thomas T.; Roop, Conard J.; Schmidt, Kenneth J.; Brewer, John

    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.

  2. 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.

  3. 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

  4. Epicardial-Derived Adrenomedullin Drives Cardiac Hyperplasia During Embryogenesis

    PubMed Central

    Wetzel-Strong, Sarah E.; Li, Manyu; Klein, Klara R.; Nishikimi, Toshio; Caron, Kathleen M.

    2014-01-01

    Background Growth promoting signals from the epicardium are essential for driving myocardial proliferation during embryogenesis. In adults, these signals become reactivated following injury and promote angiogenesis and myocardial repair. Therefore, identification of such paracrine factors could lead to novel therapeutic strategies. The multi-functional peptide adrenomedullin (Adm = gene, AM = protein) is required for normal heart development. Moreover, elevated plasma AM following myocardial infarction offers beneficial cardioprotection and serves as a powerful diagnostic and prognostic indication of disease severity. Results Here, we developed a new model of Adm overexpression by stabilizing the Adm mRNA through gene-targeted replacement of the endogenous 3′ untranslated region. As expected, Admhi/hi mice express three-times more AM than controls in multiple tissues, including the heart. Despite normal blood pressures, Admhi/hi mice unexpectedly showed significantly enlarged hearts due to increased cardiac hyperplasia during development. The targeting vector was designed to allow for reversion to wild-type levels by means of Cre-mediated modification. Using this approach, we demonstrate that AM derived from the epicardium, but not the myocardium or cardiac fibroblast, is responsible for driving cardiomyocyte hyperplasia. Conclusions AM is produced by the epicardium and drives myocyte proliferation during development, thus representing a novel and clinically relevant factor potentially related to mechanisms of cardiac repair after injury. PMID:24123312

  5. 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 μm^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.

  6. 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

  7. 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

  8. 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.

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

    NASA Astrophysics Data System (ADS)

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

    1994-08-01

    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 intrduction 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 spaceflight, and show that extensive degress of development can take place in this microgravity environment.

  10. The Velten Mood Induction Procedure: Effects on Mood and Memory.

    ERIC Educational Resources Information Center

    Riskind, John H.; And Others

    1982-01-01

    Examined the hypothesis that the self-devaluative aspects of the Velton Mood Induction Procedure (VMIP) do not lower mood but that the depression-related somatic states of the VMIP do lower mood. Found that both aspects of the VMIP have a powerful impact on mood. (Author/RC)

  11. GA3 stimulates the formation and germination of somatic embryos and the expression of a KNOTTED-like homeobox gene of Cocos nucifera (L.).

    PubMed

    Montero-Córtes, M; Sáenz, Luis; Córdova, I; Quiroz, A; Verdeil, J-L; Oropeza, C

    2010-09-01

    The micropropagation of coconut palm has progressed rapidly; yet, there are constraints with regard to the number of somatic embryos formed and their germination. To overcome these, we tested the effect of gibberellic acid and characterized genes of the KNOX family. Gibberellic acid at 0.5 muM increased 1.5-fold the number of calli forming somatic embryos and twofold the number of somatic embryos per callus, calli with germinating embryos and the number of germinating somatic embryos per callus. With regard to the study of KNOX family genes, the complete sequences of two KNOX-like genes were obtained for CnKNOX1 and CnKNOX2. The deduced amino acid sequence of both showed highly conserved domains characteristic of KNOX genes. CnKNOX1 showed high homology with KNOX class I proteins. CnKNOX1 expression was detected throughout the embryogenesis process except in somatic embryos at the pro-globular stage, and was highest in somatic embryos at the coleoptilar stage. No detection of CnKNOX1 expression occurred in calli with aberrant embryos. The addition of gibberellic acid stimulated the expression of CnKNOX1 earlier and the relative expression at all stages was higher. CnKNOX2 expression occurred at all stages peaking at the globular stage, but gibberellic acid treatment decreased the expression. Gene expression was also analyzed in tissues of different organs of adult palms. With CnKNOX1, high level of expression was found in tissues of organs with, but not in those without, meristem, whereas CnKNOX2 expression was detected in tissues with and also in those without meristem. PMID:20582418

  12. Somatic markers, working memory, and decision making.

    PubMed

    Hinson, John M; Jameson, Tina L; Whitney, Paul

    2002-12-01

    The somatic marker hypothesis formulated by Damasio (e.g., 1994; Damasio, Tranel, & Damasio, 1991) argues that affective reactions ordinarily guide and simplify decision making. Although originally intended to explain decision-making deficits in people with specific frontal lobe damage, the hypothesis also applies to decision-making problems in populations without brain injury. Subsequently, the gambling task was developed by Bechara (Bechara, Damasio, Damasio, & Anderson, 1994) as a diagnostic test of decision-making deficit in neurological populations. More recently, the gambling task has been used to explore implications of the somatic marker hypothesis, as well as to study suboptimal decision making in a variety of domains. We examined relations among gambling task decision making, working memory (WM) load, and somatic markers in a modified version of the gambling task. Increased WM load produced by secondary tasks led to poorer gambling performance. Declines in gambling performance were associated with the absence of the affective reactions that anticipate choice outcomes and guide future decision making. Our experiments provide evidence that WM processes contribute to the development of somatic markers. If WM functioning is taxed, somatic markers may not develop, and decision making may thereby suffer. PMID:12641178

  13. Cryopreservation of Arachis pintoi (leguminosae) somatic embryos.

    PubMed

    Rey, H Y; Faloci, M; Medina, R; Dolce, N; Engelmann, F; Mroginski, L

    2013-01-01

    In this study, we successfully cryopreserved cotyledonary somatic embryos of diploid and triploid Arachis pintoi cytotypes using the encapsulation-dehydration technique. The highest survival rates were obtained when somatic embryos were encapsulated in calcium alginate beads and precultured in agitated (80 rpm) liquid establishment medium (EM) with daily increasing sucrose concentration (0.50, 0.75, and 1.0 M). The encapsulated somatic embryos were then dehydrated with silica gel for 5 h to 20% moisture content (fresh weight basis) and cooled either rapidly (direct immersion in liquid nitrogen, LN) or slowly (1 degree C per min from 25 degree C to -30 degree C followed by immersion in LN). Beads were kept in LN for a minimum of 1 h and then were rapidly rewarmed in a 30 degree C water-bath for 2 min. Finally, encapsulated somatic embryos were post-cultured in agitated (80 rpm) liquid EM with daily decreasing sucrose concentration (0.75 and 0.5 M) and transferred to solidified EM. Using this protocol, we obtained 26% and 30% plant regeneration from cryopreserved somatic embryos of diploid and triploid cytotypes. No morphological abnormalities were observed in any of the plants regenerated from cryopreserved embryos and their genetic stability was confirmed with 10 isozyme systems and nine RAPD profiles. PMID:24441368

  14. Toward establishing a morphological and ultrastructural characterization of proembryogenic masses and early somatic embryos of Araucaria angustifolia (Bert.) O. Kuntze.

    PubMed

    Steiner, Neusa; Farias-Soares, Francine L; Schmidt, Éder C; Pereira, Maria L T; Scheid, Bruna; Rogge-Renner, Gladys D; Bouzon, Zenilda L; Schmidt, Daniela; Maldonado, Sara; Guerra, Miguel P

    2016-03-01

    Somatic embryogenesis is a morphogenetic route useful for the study of embryonic development, as well as the large-scale propagation of endangered species, such as the Brazilian pine (Araucaria angustifolia). In the present study, we investigated the morphological and ultrastructural organization of A. angustifolia somatic embryo development by means of optical and electron microscopy. The proembryogenic stage was characterized by the proliferation of proembryogenic masses (PEMs), which are cellular aggregates composed of embryogenic cells (ECs) attached to suspensor-like cells (SCs). PEMs proliferate through three developmental stages, PEM I, II, and III, by changes in the number of ECs and SCs. PEM III-to-early somatic embryo (SE) transition was characterized by compact clusters of ECs growing out of PEM III, albeit still connected to it by SCs. Early SEs showed a dense globular embryonic mass (EM) and suspensor region (SR) connected by embryonic tube cells (TCs). By comparison, early somatic and zygotic embryos showed similar morphology. ECs are round with a large nucleus, nucleoli, and many cytoplasmic organelles. In contrast, TCs and SCs are elongated and vacuolated with cellular dismantling which is associated with programmed cell death of SCs. Abundant starch grains were observed in the TCs and SCs, while proteins were more abundant in the ECs. Based on the results of this study, a fate map of SE development in A. angustifolia is, for the first time, proposed. Additionally, this study shows the cell biology of SE development of this primitive gymnosperm which may be useful in evolutionary studies in this area. PMID:25968333

  15. 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

  16. Cellular Mechanisms of Somatic Stem Cell Aging

    PubMed Central

    Jung, Yunjoon

    2014-01-01

    Tissue homeostasis and regenerative capacity rely on rare populations of somatic stem cells endowed with the potential to self-renew and differentiate. During aging, many tissues show a decline in regenerative potential coupled with a loss of stem cell function. Cells including somatic stem cells have evolved a series of checks and balances to sense and repair cellular damage to maximize tissue function. However, during aging the mechanisms that protect normal cell function begin to fail. In this review, we will discuss how common cellular mechanisms that maintain tissue fidelity and organismal lifespan impact somatic stem cell function. We will highlight context-dependent changes and commonalities that define aging, by focusing on three age-sensitive stem cell compartments: blood, neural, and muscle. Understanding the interaction between extrinsic regulators and intrinsic effectors that operate within different stem cell compartments is likely to have important implications for identifying strategies to improve health span and treat age-related degenerative diseases. PMID:24439814

  17. Cellular mechanisms of somatic stem cell aging.

    PubMed

    Jung, Yunjoon; Brack, Andrew S

    2014-01-01

    Tissue homeostasis and regenerative capacity rely on rare populations of somatic stem cells endowed with the potential to self-renew and differentiate. During aging, many tissues show a decline in regenerative potential coupled with a loss of stem cell function. Cells including somatic stem cells have evolved a series of checks and balances to sense and repair cellular damage to maximize tissue function. However, during aging the mechanisms that protect normal cell function begin to fail. In this review, we will discuss how common cellular mechanisms that maintain tissue fidelity and organismal lifespan impact somatic stem cell function. We will highlight context-dependent changes and commonalities that define aging, by focusing on three age-sensitive stem cell compartments: blood, neural, and muscle. Understanding the interaction between extrinsic regulators and intrinsic effectors that operate within different stem cell compartments is likely to have important implications for identifying strategies to improve health span and treat age-related degenerative diseases. PMID:24439814

  18. Somatic Mutation Favors the Evolution of Diploidy

    PubMed Central

    Orr, H. A.

    1995-01-01

    Explanations of diploidy have focused on advantages gained from masking deleterious mutations that are inherited. Recent theory has shown that these explanations are flawed. Indeed, we still lack any satisfactory explanation of diploidy in species that are asexual or that recombine only rarely. Here I consider a possibility first suggested by EFROIMSON in 1932, by MULLER in 1964 and by CROW and KIMURA in 1965: diploidy may provide protection against somatic, not inherited, mutations. I both compare the mean fitness of haploid and diploid populations that are asexual and investigate the invasion of ``diploidy'' alleles in sexual populations. When deleterious mutations are partially recessive and somatic mutation is sufficiently common, somatic mutation provides a clear advantage to diploidy in both asexual and sexual species. PMID:7768451

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

    PubMed

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

    2012-01-01

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

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

    PubMed Central

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

    2012-01-01

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

  1. Early molecular effects of ethanol during vertebrate embryogenesis.

    PubMed

    Yelin, Ronit; Kot, Hadas; Yelin, Dvir; Fainsod, Abraham

    2007-06-01

    Fetal alcohol spectrum disorder (FASD) is the combination of developmental, morphological, and neurological defects that result from exposing human embryos to ethanol (EtOH). Numerous embryonic structures are affected, leading to a complex viable phenotype affecting among others, the anterior/posterior axis, head, and eye formation. Recent studies have provided evidence suggesting that EtOH teratogenesis is mediated in part through a reduction in retinoic acid (RA) levels, targeting mainly the embryonic organizer (Spemann's organizer) and its subsequent functions. EtOH-treated Xenopus embryos were subjected to an analysis of gene expression patterns. Analysis of organizer-specific genes revealed a transient delay in the invagination of gsc- and chordin-positive cells that eventually reach their normal rostro-caudal position. Dorsal midline genes show defects along the rostro-caudal axis, lacking either their rostral (Xbra and Xnot2) or caudal (FoxA4b and Shh) expression domains. Head-specific markers like Otx2, en2, and Shh show abnormal expression patterns. Otx2 exhibits a reduction in expression levels, while en2 becomes restricted along the dorsal/ventral axis. During neurula stages, Shh becomes up-regulated in the rostral region and it is expressed in an abnormal pattern. These results and histological analysis suggest the existence of malformations in the brain region including a lack of the normal fore brain ventricle. An increase in the size of both the prechordal plate and the notochord was observed, while the spinal cord is narrower. The reduction in head and eye size was accompanied by changes in the eye markers, Pax6 and Tbx3. Our results provide evidence for the early molecular changes induced by EtOH exposure during embryogenesis, and may explain some of the structural changes that are part of the EtOH teratogenic phenotype also in FASD individuals. PMID:17286601

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

    PubMed Central

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

    2012-01-01

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

  3. Calcineurin-NFAT Signaling Controls Somatic Cell Reprogramming in a Stage-Dependent Manner.

    PubMed

    Sun, Ming; Liao, Bing; Tao, Yu; Chen, Hao; Xiao, Feng; Gu, Junjie; Gao, Shaorong; Jin, Ying

    2016-05-01

    Calcineurin-NFAT signaling is critical for early lineage specification of mouse embryonic stem cells and early embryos. However, its roles in somatic cell reprogramming remain unknown. Here, we report that calcineurin-NFAT signaling has a dynamic activity and plays diverse roles at different stages of reprogramming. At the early stage, calcineurin-NFAT signaling is transiently activated and its activation is required for successful reprogramming. However, at the late stage of reprogramming, activation of calcineurin-NFAT signaling becomes a barrier for reprogramming and its inactivation is critical for successful induction of pluripotency. Mechanistically, calcineurin-NFAT signaling contributes to the reprogramming through regulating multiple early events during reprogramming, including mesenchymal to epithelial transition (MET), cell adhesion and emergence of SSEA1(+) intermediate cells. Collectively, this study reveals for the first time the important roles of calcineurin-NFAT signaling during somatic cell reprogramming and provides new insights into the molecular regulation of reprogramming. PMID:26448199

  4. 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…

  5. Sexual Abuse: Somatic and Emotional Reactions.

    ERIC Educational Resources Information Center

    Rimza, Mary Ellen; And Others

    1988-01-01

    Chart reviews and telephone interviews with 72 sexual abuse victims found that 48 of the children had symptoms similar to the "rape trauma" syndrome. Two-thirds of victims commonly had somatic complaints (such as abdominal pain) and emotional/behavioral problems (runaway behavior, suicide attempts). (DB)

  6. Somatic cell nuclear transfer in zebrafish.

    PubMed

    Siripattarapravat, Kannika; Pinmee, Boonya; Venta, Patrick J; Chang, Chia-Cheng; Cibelli, Jose B

    2009-10-01

    We developed a method for somatic cell nuclear transfer in zebrafish using laser-ablated metaphase II eggs as recipients, the micropyle for transfer of the nucleus and an egg activation protocol after nuclear reconstruction. We produced clones from cells of both embryonic and adult origins, although the latter did not give rise to live adult clones. PMID:19718031

  7. Somatic Disorders of Childhood and Adolescence.

    ERIC Educational Resources Information Center

    Siegel, Lawrence J.

    1990-01-01

    Briefly reviews number of theories which address role of psychological factors in etiology of somatic disorders. Focuses on psychological treatment approaches that have been used to alleviate or reduce symptomatic behaviors associated with eating disorders, elimination disorders, and headaches in children. Discusses role of school psychologists in…

  8. Autophagy SEPArates germline and somatic cells.

    PubMed

    Baehrecke, Eric H

    2009-01-23

    Cellular determinants of the germline selectively accumulate in germ cell precursors and influence cell fate during early development in many organisms. Zhang et al. (2009) now report that targeted autophagy mediated by the SEPA-1 protein depletes germplasm proteins from somatic cells during early development of the nematode. PMID:19167322

  9. Psychosomatic or allergic symptoms? High levels for somatization in patients with drug intolerance.

    PubMed

    Hassel, Jessica C; Danner, Daniel; Hassel, Alexander J

    2011-10-01

    Patients with dermatological diseases often have associated psychological problems. For patients with allergic diseases, only a few publications have focused on psychological aspects. The objective of this study was to assess the psychometric profile, including somatization, depression, anxiety and health-related quality of life (HRQoL), of patients suffering from drug intolerance or hymenoptera venom allergies. In a prospective cohort study design, patients who were admitted to hospital for a challenge test for an alternative drug (n = 49, 24.5% men) or for induction of desensitization therapy with hymenoptera venom (n = 58, 37.9% men) were included. Psychometric screening questionnaires focusing on somatization (Symptom Check List), depression and anxiety (Hospital Anxiety Depression Scale), and also on HRQoL (Short Form questionnaire) were assessed. The scores were compared with population scores and between the two groups. Both groups had significantly higher somatization scores (P ≤ 0.003) than the normal population, and the challenge-test group had lower HRQoL than the normal population. Between-group analysis revealed significantly higher somatization scores in the challenge-test group (P = 0.011) and more impaired HRQoL (physical health domain P < 0.001). Anxiety/depression scores were not significantly different from those of the normal population, or between groups, although abnormally high scores for anxiety were frequent (18% and 12% for the challenge-test and allergy groups, respectively). Somatization, reduced HRQoL and anxiety seem to be part of the symptoms of patients with allergic diseases, especially for patients with drug intolerance. Standardized questionnaires could help to discover patients who may need psychological support. This may help to improve the patients' symptoms and quality of life. PMID:21767296

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

    PubMed

    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

  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. piggyBac transposon somatic mutagenesis with an activated reporter and tracker (PB-SMART) for genetic screens in mice.

    PubMed

    Landrette, Sean F; Cornett, Jonathan C; Ni, Thomas K; Bosenberg, Marcus W; Xu, Tian

    2011-01-01

    Somatic forward genetic screens have the power to interrogate thousands of genes in a single animal. Retroviral and transposon mutagenesis systems in mice have been designed and deployed in somatic tissues for surveying hematopoietic and solid tumor formation. In the context of cancer, the ability to visually mark mutant cells would present tremendous advantages for identifying tumor formation, monitoring tumor growth over time, and tracking tumor infiltrations and metastases into wild-type tissues. Furthermore, locating mutant clones is a prerequisite for screening and analyzing most other somatic phenotypes. For this purpose, we developed a system using the piggyBac (PB) transposon for somatic mutagenesis with an activated reporter and tracker, called PB-SMART. The PB-SMART mouse genetic screening system can simultaneously induce somatic mutations and mark mutated cells using bioluminescence or fluorescence. The marking of mutant cells enable analyses that are not possible with current somatic mutagenesis systems, such as tracking cell proliferation and tumor growth, detecting tumor cell infiltrations, and reporting tissue mutagenesis levels by a simple ex vivo visual readout. We demonstrate that PB-SMART is highly mutagenic, capable of tumor induction with low copy transposons, which facilitates the mapping and identification of causative insertions. We further integrated a conditional transposase with the PB-SMART system, permitting tissue-specific mutagenesis with a single cross to any available Cre line. Targeting the germline, the system could also be used to conduct F1 screens. With these features, PB-SMART provides an integrated platform for individual investigators to harness the power of somatic mutagenesis and phenotypic screens to decipher the genetic basis of mammalian biology and disease. PMID:22039523

  13. Induction machine

    DOEpatents

    Owen, Whitney H.

    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.

  14. Autosomal dominant polycystic kidney disease caused by somatic and germline mosaicism.

    PubMed

    Tan, A Y; Blumenfeld, J; Michaeel, A; Donahue, S; Bobb, W; Parker, T; Levine, D; Rennert, H

    2015-04-01

    Autosomal dominant polycystic kidney disease (ADPKD) is a heterogeneous genetic disorder caused by loss of function mutations of PKD1 or PKD2 genes. Although PKD1 is highly polymorphic and the new mutation rate is relatively high, the role of mosaicism is incompletely defined. Herein, we describe the molecular analysis of ADPKD in a 19-year-old female proband and her father. The proband had a PKD1 truncation mutation c.10745dupC (p.Val3584ArgfsX43), which was absent in paternal peripheral blood lymphocytes (PBL). However, very low quantities of this mutation were detected in the father's sperm DNA, but not in DNA from his buccal cells or urine sediment. Next generation sequencing (NGS) analysis determined the level of this mutation in the father's PBL, buccal cells and sperm to be ∼3%, 4.5% and 10%, respectively, consistent with somatic and germline mosaicism. The PKD1 mutation in ∼10% of her father's sperm indicates that it probably occurred early in embryogenesis. In ADPKD cases where a de novo mutation is suspected because of negative PKD gene testing of PBL, additional evaluation with more sensitive methods (e.g. NGS) of the proband PBL and paternal sperm can enhance detection of mosaicism and facilitate genetic counseling. PMID:24641620

  15. 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.

  16. 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

  17. 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.

  18. Reprogrammed pluripotent stem cells from somatic cells.

    PubMed

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-06-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-like pluripotency by transferring somatic cell nuclei into oocytes, by cell fusion with pluripotent cells. Retroviral-mediated introduction of four factors, Oct4, Sox2, Klf4 and c-Myc can successfully reprogram somatic cells into ES cell-like pluripotent stem cells, known as induced pluripotent stem (iPS) cells. These cells closely resemble ES cells in gene expression pattern, cell biologic and phenotypic characteristics. However, to reach the eventual goal of clinical application, it is necessary to overcome the major drawbacks such as low reprogramming efficiency and genomic alterations due to viral integration. In this review, we discuss the current reprogramming techniques and mechanisms of nuclear reprogramming induced by transcription factor transduction. PMID:24298328

  19. Somatic cell nuclear transfer in the mouse.

    PubMed

    Kishigami, Satoshi; Wakayama, Teruhiko

    2009-01-01

    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. PMID:19085136

  20. 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…

  1. 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...

  2. Autophagy induction by sera from women undergoing an in vitro fertilization cycle varies with subsequent outcome.

    PubMed

    Sisti, Giovanni; Kanninen, Tomi T; Di Tommaso, Mariarosaria; Witkin, Steven S; Spandorfer, Steven D

    2016-09-01

    Autophagy maintains intracellular homeostasis during placental development and embryogenesis. We evaluated if differences in the autophagy-inducing capacity of sera from women undergoing an in vitro fertilization (IVF) cycle predicted subsequent pregnancy outcome. In this retrospective study, sera collected from 94 women at the time of intrauterine embryo implantation were incubated with peripheral blood mononuclear cells (PBMCs) from healthy donors. The PBMCs were lysed and autophagy induction measured by determination of the p62 concentration. A reduced capacity for autophagy induction was associated with defective implantation while an elevated level of autophagy was associated with ectopic pregnancy. PMID:27343871

  3. 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, β-alanine metabolism, and protein export are intensively activated in the embryos of middle age. The old embryos (48-72 h) elevated expression of proteins implicated in fatty acid metabolism and morphogenesis indicate their functionality for the formation and development of organs and dorsal closure, in which the biological pathways of fatty acid metabolism and RNA transport are highly activated. These findings add novel understanding to the molecular details of honey bee embryogenesis, in which the programmed activation of the proteome matches with the physiological transition observed during

  4. 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, β-alanine metabolism, and protein export are intensively activated in the embryos of middle age. The old embryos (48–72 h) elevated expression of proteins implicated in fatty acid metabolism and morphogenesis indicate their functionality for the formation and development of organs and dorsal closure, in which the biological pathways of fatty acid metabolism and RNA transport are highly activated. These findings add novel understanding to the molecular details of honey bee embryogenesis, in which the programmed activation of the proteome matches with the physiological transition observed during

  5. Germ-granule components prevent somatic development in the C. elegans germline

    PubMed Central

    Knutson, Andrew Kekūpa'a; Egelhofer, Thea A.; Campbell, Anne C.; Strome, Susan

    2014-01-01

    Summary Specialized ribonucleoprotein organelles collectively known as germ granules are found in the germline cytoplasm from worms to humans [1]. In Drosophila, germ granules have been implicated in germline determination [2]. C. elegans germ granules, known as P granules, do not appear to be required for primordial germ cell (PGC) determination [3], but their components are still needed for fertility [4–6]. One potential role for P granules is to maintain germline fate and totipotency. This is suggested by the loss of P granules from germ cells that transform into somatic cell types, e.g. in germlines lacking MEX-3 and GLD-1 or upon neuronal induction by CHE-1 [7, 8]. However, it has not been established whether loss of P granules is the cause or effect of cell-fate transformation. To test cause-effect, we severely compromised P granules by simultaneously knocking down factors that nucleate granule formation (PGL-1 and PGL-3) and promote their perinuclear localization (GLH-1 and GLH-4) [9], and investigated if that causes germ cells to lose totipotency and initiate somatic reprogramming. We found that compromising P granules causes germ cells to express neuronal and muscle markers and send out neurite-like projections, suggesting that P granules maintain totipotency and germline identity by antagonizing somatic fate. PMID:24746798

  6. Callus induction and plant regeneration from mature zygotic embryos of a tetraploid Alstroemeria (A. pelegrina × A. psittacina).

    PubMed

    Hutchinson, M J; Tsujita, J M; Saxena, P K

    1994-12-01

    A simple procedure was developed to induce callus growth and whole plant regeneration for a tetraploid cultivar of Alstroemeria. The callus, induced from mature zygotic embryos cultured on a medium supplemented with 20 μM kinetin with 10 or 20 μM NAA, could be maintained for one year without any loss of regeneration potential. Maximum frequency of regeneration (40%) was obtained with calli maintained on the medium containing 20 μM kinetin and 20 μM NAA. Whole plant regeneration occurred via somatic embryogenesis in the absence of growth regulators and the plantlets grew to maturity and flowered in the greenhouse conditions. PMID:24192891

  7. A matter of identity - Phenotype and differentiation potential of human somatic stem cells.

    PubMed

    New, S E P; Alvarez-Gonzalez, C; Vagaska, B; Gomez, S G; Bulstrode, N W; Madrigal, A; Ferretti, P

    2015-07-01

    Human somatic stem cells with neural differentiation potential can be valuable for developing cell-based therapies, including treatment of birth-related defects, while avoiding issues associated with cell reprogramming. Precisely defining the "identity" and differentiation potential of somatic stem cells from different sources, has proven difficult, given differences in sets of specific markers, protocols used and lack of side-by-side characterization of these cells in different studies. Therefore, we set to compare expression of mesenchymal and neural markers in human umbilical cord-derived mesenchymal stem cells (UC-MSCs), pediatric adipose-derived stem cells (p-ADSCs) in parallel with human neural stem cells (NSCs). We show that UC-MSCs at a basal level express mesenchymal and so-called "neural" markers, similar to that we previously reported for the p-ADSCs. All somatic stem cell populations studied, independently from tissue and patient of origin, displayed a remarkably similar expression of surface markers, with the main difference being the restricted expression of CD133 and CD34 to NSCs. Expression of certain surface and neural markers was affected by the expansion medium used. As predicted, UC-MSCs and p-ADSCs demonstrated tri-mesenchymal lineage differentiation potential, though p-ADSCs display superior chondrogenic differentiation capability. UC-MSCs and p-ADSCs responded also to neurogenic induction by up-regulating neuronal markers, but crucially they appeared morphologically immature when compared with differentiated NSCs. This highlights the need for further investigation into the use of these cells for neural therapies. Crucially, this study demonstrates the lack of simple means to distinguish between different cell types and the effect of culture conditions on their phenotype, and indicates that a more extensive set of markers should be used for somatic stem cell characterization, especially when developing therapeutic approaches. PMID:25957945

  8. 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.

  9. A SOMATIC-MARKER THEORY OF ADDICTION

    PubMed Central

    Verdejo-García, Antonio; Bechara, Antoine

    2009-01-01

    Similar to patients with ventromedial prefrontal cortex (VMPC) lesions, substance abusers show altered decision-making, characterized by a tendency to choose the immediate reward, at the expense of negative future consequences. The somatic-marker model proposes that decision-making depends on neural substrates that regulate homeostasis, emotion and feeling. According to this model, there should be a link between alterations in processing emotions in substance abusers, and their impairments in decision-making. A growing evidence from neuroscientific studies indicate that core aspects of addiction may be explained in terms of abnormal emotional/homeostatic guidance of decision-making. Behavioural studies have revealed emotional processing and decision-making deficits in substance abusers. Neuroimaging studies have shown that altered decision-making in addiction is associated with abnormal functioning of a distributed neural network critical for the processing of emotional information, and the experience of “craving”, including the VMPC, the amygdala, the striatum, the anterior cingulate cortex, and the insular/somato-sensory cortices, as well as non-specific neurotransmitter systems that modulate activities of neural processes involved in decision-making. The aim of this paper is to review this growing evidence, and to examine the extent of which these studies support a somatic-marker theory of addiction. We conclude that there are at least two underlying types of dysfunctions where emotional signals (somatic-markers) turns in favor of immediate outcomes in addiction: (1) a hyperactivity in the amygdala or impulsive system, which exaggerates the rewarding impact of available incentives, and (2) hypoactivity in the prefrontal cortex or reflective system, which forecasts the long-term consequences of a given action. PMID:18722390

  10. [Stress theories and the somatization process].

    PubMed

    Dantzer, R

    1995-12-01

    Stress theories aim at understanding pathophysiology of psychosomatic disorders. The first stress theories have been inspired by the principles of homeostasis. They view the response to stressors as a quasi reflex reaction which aims at normalizing disturbed homeostasis. More modern stress theories emphasize the intermediate role of cognitive and behavioural processes in the determinism of neuroendocrine and neurovegetative responses to stressors. Active attempts to control the situation are associated with activation of the sympathetic and adrenal medullary system whereas loss of control is associated with activation of the hypothalamic-pituitary-adrenal axis. Since the functional consequences of the activation of each of these physiological systems are not the same, the risk factors corresponding to each coping strategy are not the same. Whatever their details, physiological and psychobiological stress theories all emphasize the influence of psychic factors on bodily functions. However, mental states do not function independently of bodily functions. In the case of the influences of stress on immunity for instance, it has been shown that these influences represent the counterpart of feedback regulatory mechanisms in which the ability of the brain to regulate immune responses depends on the capacity of the immune system to influence brain functions. Activation of the immune system during infection or inflammation is accompanied by profound metabolic, neuroendocrine and behavioural changes which are mediated by the effects of immune products known as cytokines on brain cell targets. In view of the reciprocal relationships between peripheral organic systems and the brain, a purely psychosomatic view, from the psyche to the soma, is therefore no longer tenable. In addition, biological accounts of somatization processes run into the risk of minimizing the importance of perception and representation of somatic symptoms. Amplification of somatic symptoms is a common

  11. 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

  12. Clarifying tetrapod embryogenesis, a physicist's point of view

    NASA Astrophysics Data System (ADS)

    Fleury, V.

    2009-03-01

    The origin of tetrapods is a complex question that webs together genetic, paleontological, developmental and physical facts. Basically, the development of embryos is described by a complex mix of mechanical movements and biochemical inductions of genetic origin. It is difficult to sort out in this scientific question what are the fundamental features imposed by conservation laws of physics, and by force equilibria, and what can be ascribed to successive, very specific, stop-and-go inductions of genetic nature. A posteriori, evolution selects the parameters of this process as found in the observed species. Whether there is a general law to animal formation seems out of the question. However, several concepts developed in biology, like the concept of “organizer” seem questionable from a physics point of view, since the entire deformation and force field should be the “organizer” of development, and one can hardly ascribe such a role to a single small area of the embryo body. In the same spirit, the concept of “positional information” encapsulated in concentration of chemicals seems questionable since the deformation and force fields in embryonic tissues are tensors. Finally, the concept of a development organized in space along three orthogonal (“Cartesian”) axes associated to chemical gradients seems also questionable, since early embryo development is driven by complex vortex fields, with hyperbolic trajectories which span the entire embryo. Such hyperbolic trajectories are best understood by a description in terms of dipolar components of the morphogenetic forces, whose projections along orthogonal axe have no specific meaning except as a mathematical tool. I review here the present state of description of several aspects of tetrapods morphogenesis and evolution, from the point of view of physics. It is getting clear that several basic features of tetrapods body are a direct consequences of fundamental laws of physics. Several lines of work

  13. 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

  14. Confidence-based somatic mutation evaluation and prioritization.

    PubMed

    Löwer, Martin; Renard, Bernhard Y; de Graaf, Jos; Wagner, Meike; Paret, Claudia; Kneip, Christoph; Türeci, Ozlem; Diken, Mustafa; Britten, Cedrik; Kreiter, Sebastian; Koslowski, Michael; Castle, John C; Sahin, Ugur

    2012-01-01

    Next generation sequencing (NGS) has enabled high throughput discovery of somatic mutations. Detection depends on experimental design, lab platforms, parameters and analysis algorithms. However, NGS-based somatic mutation detection is prone to erroneous calls, with reported validation rates near 54% and congruence between algorithms less than 50%. Here, we developed an algorithm to assign a single statistic, a false discovery rate (FDR), to each somatic mutation identified by NGS. This FDR confidence value accurately discriminates true mutations from erroneous calls. Using sequencing data generated from triplicate exome profiling of C57BL/6 mice and B16-F10 melanoma cells, we used the existing algorithms GATK, SAMtools and SomaticSNiPer to identify somatic mutations. For each identified mutation, our algorithm assigned an FDR. We selected 139 mutations for validation, including 50 somatic mutations assigned a low FDR (high confidence) and 44 mutations assigned a high FDR (low confidence). All of the high confidence somatic mutations validated (50 of 50), none of the 44 low confidence somatic mutations validated, and 15 of 45 mutations with an intermediate FDR validated. Furthermore, the assignment of a single FDR to individual mutations enables statistical comparisons of lab and computation methodologies, including ROC curves and AUC metrics. Using the HiSeq 2000, single end 50 nt reads from replicates generate the highest confidence somatic mutation call set. PMID:23028300

  15. Confidence-based Somatic Mutation Evaluation and Prioritization

    PubMed Central

    de Graaf, Jos; Wagner, Meike; Paret, Claudia; Kneip, Christoph; Türeci, Özlem; Diken, Mustafa; Britten, Cedrik; Kreiter, Sebastian; Koslowski, Michael; Castle, John C.; Sahin, Ugur

    2012-01-01

    Next generation sequencing (NGS) has enabled high throughput discovery of somatic mutations. Detection depends on experimental design, lab platforms, parameters and analysis algorithms. However, NGS-based somatic mutation detection is prone to erroneous calls, with reported validation rates near 54% and congruence between algorithms less than 50%. Here, we developed an algorithm to assign a single statistic, a false discovery rate (FDR), to each somatic mutation identified by NGS. This FDR confidence value accurately discriminates true mutations from erroneous calls. Using sequencing data generated from triplicate exome profiling of C57BL/6 mice and B16-F10 melanoma cells, we used the existing algorithms GATK, SAMtools and SomaticSNiPer to identify somatic mutations. For each identified mutation, our algorithm assigned an FDR. We selected 139 mutations for validation, including 50 somatic mutations assigned a low FDR (high confidence) and 44 mutations assigned a high FDR (low confidence). All of the high confidence somatic mutations validated (50 of 50), none of the 44 low confidence somatic mutations validated, and 15 of 45 mutations with an intermediate FDR validated. Furthermore, the assignment of a single FDR to individual mutations enables statistical comparisons of lab and computation methodologies, including ROC curves and AUC metrics. Using the HiSeq 2000, single end 50 nt reads from replicates generate the highest confidence somatic mutation call set. PMID:23028300

  16. 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

  17. Evaluation of Nine Somatic Variant Callers for Detection of Somatic Mutations in Exome and Targeted Deep Sequencing Data

    PubMed Central

    Krøigård, Anne Bruun; Thomassen, Mads; Lænkholm, Anne-Vibeke; Kruse, Torben A.; Larsen, Martin Jakob

    2016-01-01

    Next generation sequencing is extensively applied to catalogue somatic mutations in cancer, in research settings and increasingly in clinical settings for molecular diagnostics, guiding therapy decisions. Somatic variant callers perform paired comparisons of sequencing data from cancer tissue and matched normal tissue in order to detect somatic mutations. The advent of many new somatic variant callers creates a need for comparison and validation of the tools, as no de facto standard for detection of somatic mutations exists and only limited comparisons have been reported. We have performed a comprehensive evaluation using exome sequencing and targeted deep sequencing data of paired tumor-normal samples from five breast cancer patients to evaluate the performance of nine publicly available somatic variant callers: EBCall, Mutect, Seurat, Shimmer, Indelocator, Somatic Sniper, Strelka, VarScan 2 and Virmid for the detection of single nucleotide mutations and small deletions and insertions. We report a large variation in the number of calls from the nine somatic variant callers on the same sequencing data and highly variable agreement. Sequencing depth had markedly diverse impact on individual callers, as for some callers, increased sequencing depth highly improved sensitivity. For SNV calling, we report EBCall, Mutect, Virmid and Strelka to be the most reliable somatic variant callers for both exome sequencing and targeted deep sequencing. For indel calling, EBCall is superior due to high sensitivity and robustness to changes in sequencing depths. PMID:27002637

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

    PubMed

    Dasmahapatra, Asok K; Khan, Ikhlas A

    2015-01-01

    We aimed to investigate the impact of the epigenome in inducting fetal alcohol spectrum disorder (FASD) phenotypes in Japanese rice fish embryogenesis. One of the significant events in epigenome is DNA methylation which is catalyzed by DNA methyltransferase (DNMT) enzymes. We analyzed DNMT enzyme mRNA expressions in Japanese rice fish development starting from fertilized eggs to hatching and also in embryos exposed for first 48h of development either to ethanol (300mM) or to 5-azacytidine (5-azaC; 2mM), an inhibitor of DNMT enzyme activity. As observed in FASD phenotypes, 5-azaC exposure was able to induce microcephaly and craniofacial cartilage deformities in Japanese rice fish. Moreover, we have observed that expression of DNMTs (dnmt1, dnmt3aa, and dnmt3bb.1) are developmentally regulated; high mRNA copies were found in early stages (1-2day-post-fertilization, dpf), followed by gradual reduction until hatched. In ethanol-treated embryos, compared to controls, dnmt1 mRNA is in reduced level in 2dpf and in enhanced level in 6dpf embryos. While dnmt3aa and 3bb.1 remained unaltered. In contrast, embryos exposed to 5-azaC have an enhanced level of dnmt1 and dnmt3bb.1 mRNAs both in 2 and 6dpf embryos while dnmt3aa is enhanced only in 6dpf embryos. Moreover, endocannabinoid receptor 1a (cnr1a) mRNA which was found to be reduced by ethanol remained unaltered and cnr1b and cnr2 mRNAs, which were remained unaltered by ethanol, were increased significantly by 5-azaC in 6dpf embryos. This study indicates that the craniofacial defects observed in FASD phenotypes are the results of dysregulations in DNMT expressions. PMID:26183885

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

    PubMed

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

    2016-01-01

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

  20. Germline and somatic mutations in meningiomas.

    PubMed

    Smith, Miriam J

    2015-04-01

    Meningiomas arise from the arachnoid layer of the meninges that surround the brain and spine. They account for over one third of all primary central nervous system tumors in adults and confer a significant risk of location-dependent morbidity due to compression or displacement. A significant increase in risk of meningiomas is associated with neurofibromatosis type 2 (NF2) disease through mutation of the NF2 gene. In addition, approximately 5% of individuals with schwannomatosis disease develop meningiomas, through mutation of the SWI/SNF chromatin remodeling complex subunit, SMARCB1. Recently, a second SWI/SNF complex subunit, SMARCE1, was identified as a cause of clear cell meningiomas, indicating a wider role for this complex in meningioma disease. The sonic hedgehog (SHH)-GLI1 signaling pathway gene, SUFU, has also been identified as the cause of hereditary multiple meningiomas in a large Finnish family. The recent identification of somatic mutations in components of the SHH-GLI1 and AKT1-MTOR signaling pathways indicates the potential for cross talk of these pathways in the development of meningiomas. This review describes the known meningioma predisposition genes and their links to the recently identified somatic mutations. PMID:25857641

  1. [Behavioral somatic disorders in hospitalized children].

    PubMed

    Guasco, G; Gugliada, D; Gamalero, G

    1989-01-01

    The research has investigated the occurrence of somatic and behavioural disorders in 100 hospitalised children. A hundred subjects, 55 males & 45 females, aged between 6 and 14 years were asked to fill in questionnaires. These, which were of a completely new type, related to 12 situations in a typical day. The results showed statistically significant differences between the two sexes. Girls manifested a much higher percentage of disorders than did boys. Further, young children and especially pre-adolescents (subjects aged 10-11) manifested more disturbances than did those in the adolescent category. Of the subjects 32% showed a number of disorders below the norm; 36% of the cases were within normal values, 17% were above the norm and the remaining 15% of the subjects were considered to be of particular interest. The most frequent somatic disorders were in heart-rate variations, abnormal sweating (especially of the hands when being orally tested at school), abdominal-aches and headaches. Of the behavioural disorders the most frequent were in the inability to stand still and nail-biting. Also worthy of note, though less frequent, were disorders in eating and in sleeping. It was especially at the end of the day ("before going to sleep") that all these problems occurred. They were also frequent, however, during the periods "at school", "during oral tests" and "watching television". The results obtained in parallel research on 125 primary school children confirm all of the above findings. PMID:2636381

  2. 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

  3. The IMD innate immunity pathway of Drosophila influences somatic sex determination via regulation of the Doa locus.

    PubMed

    Zhao, Yunpo; Cocco, Claudia; Domenichini, Severine; Samson, Marie-Laure; Rabinow, Leonard

    2015-11-15

    The IMD pathway induces the innate immune response to infection by gram-negative bacteria. We demonstrate strong female-to-male sex transformations in double mutants of the IMD pathway in combination with Doa alleles. Doa encodes a protein kinase playing a central role in somatic sex determination through its regulation of alternative splicing of dsx transcripts. Transcripts encoding two specific Doa isoforms are reduced in Rel null mutant females, supporting our genetic observations. A role for the IMD pathway in somatic sex determination is further supported by the induction of female-to-male sex transformations by Dredd mutations in sensitized genetic backgrounds. In contrast, mutations in either dorsal or Dif, the two other NF-κB paralogues of Drosophila, display no effects on sex determination, demonstrating the specificity of IMD signaling. Our results reveal a novel role for the innate immune IMD signaling pathway in the regulation of somatic sex determination in addition to its role in response to microbial infection, demonstrating its effects on alternative splicing through induction of a crucial protein kinase. PMID:26434917

  4. The δ-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 δ-cyclin genes expression under slow horizontal clinorotation and in the laboratory control. Some backlog of the δ1-cyclin genes expression at early stages of embryogenesis under clinorotation was revealed in comparison with the laboratory control. The similar level of the δ3-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 δ1-cyclin expression at early stages of embryogenesis.

  5. Notum is required for neural and head induction via Wnt deacylation, oxidation and inactivation

    PubMed Central

    Zhang, Xinjun; Cheong, Seong-Moon; Amado, Nathalia G.; Reis, Alice H.; MacDonald, Bryan T.; Zebisch, Matthias; Jones, E. Yvonne; Abreu, Jose Garcia; He, Xi

    2015-01-01

    Summary Secreted Wnt morphogens are essential for embryogenesis and homeostasis, and require a lipid/palmitoleoylate modification for receptor binding and activity. Notum is a secreted Wnt antagonist that belongs to the α/β hydrolase superfamily, but its mechanism of action and roles in vertebrate embryogenesis are not fully understood. Here we report that Notum hydrolyzes the Wnt palmitoleoylate adduct extracellularly, resulting in inactivated Wnt proteins that form oxidized oligomers incapable of receptor binding. Thus Notum is a Wnt deacylase, and palmitoleoylation is obligatory for the Wnt structure that maintains its active monomeric conformation. Notum is expressed in naïve ectoderm and neural plate in Xenopus and is required for neural and head induction. These findings suggest that distinct mechanisms of Wnt inactivation by the Tiki protease in the Organizer and the Notum deacylase in presumptive neuroectoderm orchestrate vertebrate brain development. PMID:25771893

  6. Convergent occurrence of the developmental hourglass in plant and animal embryogenesis?

    PubMed Central

    Cridge, Andrew G.; Dearden, Peter K.; Brownfield, Lynette R.

    2016-01-01

    Background The remarkable similarity of animal embryos at particular stages of development led to the proposal of a developmental hourglass. In this model, early events in development are less conserved across species but lead to a highly conserved ‘phylotypic period’. Beyond this stage, the model suggests that development once again becomes less conserved, leading to the diversity of forms. Recent comparative studies of gene expression in animal groups have provided strong support for the hourglass model. How and why might such an hourglass pattern be generated? More importantly, how might early acting events in development evolve while still maintaining a later conserved stage? Scope The discovery that an hourglass pattern may also exist in the embryogenesis of plants provides comparative data that may help us explain this phenomenon. Whether the developmental hourglass occurs in plants, and what this means for our understanding of embryogenesis in plants and animals is discussed. Models by which conserved early-acting genes might change their functional role in the evolution of gene networks, how networks buffer these changes, and how that might constrain, or confer diversity, of the body plan are also discused. Conclusions Evidence of a morphological and molecular hourglass in plant and animal embryogenesis suggests convergent evolution. This convergence is likely due to developmental constraints imposed upon embryogenesis by the need to produce a viable embryo with an established body plan, controlled by the architecture of the underlying gene regulatory networks. As the body plan is largely laid down during the middle phases of embryo development in plants and animals, then it is perhaps not surprising this stage represents the narrow waist of the hourglass where the gene regulatory networks are the oldest and most robust and integrated, limiting species diversity and constraining morphological space. PMID:27013176

  7. Expression of the Xenopus GTP-binding protein gene Ran during embryogenesis.

    PubMed

    Onuma, Y; Nishihara, R; Takahashi, S; Tanegashima, K; Fukui, A; Asashima, M

    2000-06-01

    The Ran gene family encodes small GTP binding proteins that are associated with a variety of nuclear processes. We isolated a Xenopus Ran cDNA and analyzed the pattern of expression of this gene during embryogenesis. Ran is expressed maternally and later in the CNS, neural crest, mesenchyme, eyes, and otic vesicles. However, expression is not detected in the somites or the notochord. PMID:11180838

  8. 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

  9. 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

  10. Key roles of the Broad-Complex gene in insect embryogenesis.

    PubMed

    Piulachs, Maria-Dolors; Pagone, Viviana; Bellés, Xavier

    2010-06-01

    The Broad-Complex (BR-C) is a primary response gene in the ecdysteroid signaling pathway which encodes a family of transcription factors that play a key role in metamorphic processes. With the aim of studying the possible functions of BR-C in the embryogenesis of a short germ band insect, we cloned BR-C cDNAs in the cockroach Blattella germanica (BgBR-C) and obtained the full coding region of six BR-C isoforms (Z1-Z6) of which, Z1-Z5 have homologous sequences in other insects, whereas Z6 is new. Temporal-expression patterns indicate that BgBR-C isoforms are present throughout the embryogenesis of B. germanica, although with weak fluctuations. Silencing all BgBR-C isoforms in the embryo through parental RNAi elicited a diversity of phenotypes. These phenotypes suggest roles for BgBR-C in different embryogenesis processes of B. germanica, mainly in the formation of the germ band, in the transition from 30% to 35% of total development, when the amnion and serosa rupture and the secondary dorsal organ is formed, and in the hatching process, which involves neural, endocrine and muscular coordination. PMID:20403438

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

    PubMed Central

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

    2016-01-01

    TAF4 (TATA-binding protein-associated factor 4) and its paralogue TAF4b are components of the TFIID core module. We inactivated the murine Taf4a gene to address Taf4 function during embryogenesis. Here we show that Taf4a−/− embryos survive until E9.5 where primary germ layers and many embryonic structures are identified showing Taf4 is dispensable for their specification. In contrast, Taf4 is required for correct patterning of the trunk and anterior structures, ventral morphogenesis and proper heart positioning. Overlapping expression of Taf4a and Taf4b during embryogenesis suggests their redundancy at early stages. In agreement with this, Taf4a−/− embryonic stem cells (ESCs) are viable and comprise Taf4b-containing TFIID. Nevertheless, Taf4a−/− ESCs do not complete differentiation into glutamatergic neurons and cardiomyocytes in vitro due to impaired preinitiation complex formation at the promoters of critical differentiation genes. We define an essential role of a core TFIID TAF in differentiation events during mammalian embryogenesis. PMID:27026076

  12. 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.

  13. Interactions between alpha-tocopherol, polyunsaturated fatty acids, and lipoxygenases during embryogenesis

    PubMed Central

    Lebold, Katie M; Traber, Maret G

    2013-01-01

    α-Tocopherol is a lipid-soluble antioxidant that is specifically required for reproduction and embryogenesis. However, since its discovery, α-tocopherol’s specific biologic functions, other than as an antioxidant, and the mechanism(s) mediating its requirement for embryogenesis, remain unknown. As an antioxidant, α-tocopherol protects polyunsaturated fatty acids (PUFAs) from lipid peroxidation. α-Tocopherol is likely 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 α-tocopherol may directly protect, or it may mediate the production and/or actions of these lipid mediators. In this review, we discuss how α-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-lipoxygenase and 3) modulates 5-lipoxygenase activity. The application and implication of such interactions with be discussed in the context α-tocopherol requirements during embryogenesis. PMID:23920314

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

    PubMed

    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

  15. Sox2/Oct4: A delicately balanced partnership in pluripotent stem cells and embryogenesis.

    PubMed

    Rizzino, Angie; Wuebben, Erin L

    2016-06-01

    Considerable progress has been made in understanding the roles of Sox2 and Oct4 in embryonic stem cells and mammalian embryogenesis. Specifically, significant progress has been made in answering three questions about the functions of Sox2 and Oct4, which are the focus of this review. 1) Are the first or second cell lineage decisions during embryogenesis controlled by Oct4 and/or Sox2? 2) Do the levels of Oct4 and Sox2 need to be maintained within narrow limits to promote normal development and to sustain the self-renewal of pluripotent stem cells? 3) Do Oct4 and Sox2 work closely together or is the primary role of Sox2 in pluripotent cells to ensure the expression of Oct4? Although significant progress has been made in answering these questions, additional studies are needed to resolve several important remaining issues. Nonetheless, the preponderance of the evidence suggests there is considerable crosstalk between Sox2 and Oct4, and further suggests Sox2 and Oct4 function as molecular rheostats and utilize negative feedback loops to carefully balance their expression and other critical genes during embryogenesis. This article is part of a Special Issue entitled: The Oct transcription factor family, edited by Dr. Dean Tantin. PMID:26992828

  16. 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

  17. 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.

  18. 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.

  19. 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…

  20. Human somatic cell nuclear transfer is alive and well.

    PubMed

    Cibelli, Jose B

    2014-06-01

    In this issue, Chung et al. (2014) generate human embryonic stem cells by fusing an adult somatic cell to a previously enucleated human oocyte, in agreement with recent reports by the Mitalipov and Egli groups. We can now safely say that human somatic cell nuclear transfer is alive and well. PMID:24905159

  1. Expressive Writing Intervention for Adolescents' Somatic Symptoms and Mood

    ERIC Educational Resources Information Center

    Soliday, Elizabeth; Garofalo, John P.; Rogers, Debra

    2004-01-01

    The effects of a widely used expressive writing intervention on adolescents' somatic symptoms, distress, and positive psychological functioning were evaluated. Eighth-grade (n = 106) students were randomly assigned to write about either an emotional or a neutral topic for 3 consecutive days. Students completed measures of somatic symptoms, medical…

  2. 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).…

  3. Changes in somatic cell structure during senescence of Volvox carteri.

    PubMed

    Pommerville, J C; Kochert, G D

    1981-06-01

    Senescence of the terminally differentiated somatic cells of the green alga, Volvox carteri f. weismannia, was investigated by light, fluorescence, and electron microscopy. Viability of the somatic cell population, as determined by trypan blue or erythrosin B exclusion, showed a sharp reduction beginning 144 h after the somatic cells had lost the ability to divide. This increased mortality rate was correlated at the light microscopic level with a retraction of the somatic cell cytoplasm, a reduction in chloroplast autofluorescence (and total chlorophyll content), and a decline in the number of vacuoles which could be localized with 9-aminoacridine fluorescence microscopy. Nuclear fluorescence with acridine orange remained unaffected during this time. Lipid bodies increased in older cells, and total lipid analysis showed a sharp increase beginning 96 h after the somatic cells had stopped dividing. Electron microscopic comparison between young (48--72 h) and old (168 h) somatic cells showed a disorganization of chloroplast structure, a decline in the number of cytoplasmic ribosomes, and, substantiating the light microscopy, and accumulation of lipid bodies in the cytoplasm of the older cells. The results demonstrate progressive changes in somatic cell structure with age and are suggestive of cells under nutrient stress even though they are in nutrient medium. Therefore senescence and death of the V. carteri somatic cells may be caused, in part, by an inability to take up or utilize nutrients present in the culture medium. PMID:7285941

  4. 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…

  5. Depression, Health, and Somatic Complaints in Older Adults.

    ERIC Educational Resources Information Center

    Mahurin, Kathleen A.; Gatz, Margaret

    Although depression is considered to be common in the elderly, reliable rates of prevalence are lacking. Studies have shown that age differences on measures of depressive symptomatology can be attributed to higher levels of somatic complaints. In order to examine whether the association between somatic and depressive symptoms varies as a function…

  6. Links among emotional awareness, somatic awareness and autonomic homeostatic processing.

    PubMed

    Kanbara, Kenji; Fukunaga, Mikihiko

    2016-01-01

    Emotional awareness and somatic interoceptive awareness are essential processes for human psychosomatic health. A typical trait of lacking emotional awareness related to psychosomatic symptoms is alexithymia. In contrast, alexisomia refers to the trait of lacking somatic awareness. Links between emotional and somatic awareness and homeostatic processing are also significant for the psychosomatic health. The purpose of the present paper is to review the links among emotional awareness, somatic interoceptive awareness and autonomic homeostatic processing. On the basis of the collected evidence, the following arguments were presented(1): (1) The main subcortical neural substrates for these processes are limbic-related systems, which are also responsible for autonomic functions for optimization of homeostatic efficiency. (2) Considerable studies have shown that autonomic activity and/or reactivity to stress correlate with both emotional and interoceptive awareness. A hypothesis was advocated about the links between the two types of awareness and autonomic function: Autonomic dysfunction, especially high sympathetic tone at baseline and/or attenuated reactivity or variability to stress, appears to be involved in disturbance of emotional and interoceptive awareness. (3) Several studies suggest that a link or a cooperative relationship exists between emotional and somatic awareness, and that somatic awareness is the more fundamental of the two types of awareness. Emotional awareness, somatic awareness and autonomic homeostatic processing generally occur in parallel or concurrently. However, some complex features of pathologies include coexistence of reduced interoceptive awareness and somatosensory amplification. The autonomic homeostatic process is fundamentally involved in emotional and somatic awareness. Investigation of these types of awareness with both neuroimaging evaluations and estimation of peripheral autonomic function are required as next steps for exploration

  7. Somatic cell genetic approaches to Down's syndrome.

    PubMed

    Patterson, D; Jones, C; Scoggin, C; Miller, Y E; Graw, S

    1982-01-01

    Somatic cell genetic analysis of mutants of Chinese hamster ovary cells with deficient purine synthesis and of hybrids between these mutants and human cells is described. Data are presented substantiating that two genes for enzymes of purine synthesis, AdeC and AdeG, can be coordinately regulated in mammalian cells. Analysis of a human-hamster hybrid cell, Ade C/21, which contains a normal complement of hamster chromosomes and human chromosome 21 as its only human genetic component recognizable by electrophoretic and immunogenetic techniques demonstrates that genes associated with the presence of human chromosome 21 and required for the synthesis of specific polypeptides and specific human lethal cell surface antigens can be detected in these hybrids. PMID:6217778

  8. 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

  9. How Somatic Adult Tissues Develop Organizer Activity.

    PubMed

    Vogg, Matthias C; Wenger, Yvan; Galliot, Brigitte

    2016-01-01

    The growth and patterning of anatomical structures from specific cellular fields in developing organisms relies on organizing centers that instruct surrounding cells to modify their behavior, namely migration, proliferation, and differentiation. We discuss here how organizers can form in adult organisms, a process of utmost interest for regenerative medicine. Animals like Hydra and planarians, which maintain their shape and fitness thanks to a highly dynamic homeostasis, offer a useful paradigm to study adult organizers in steady-state conditions. Beside the homeostatic context, these model systems also offer the possibility to study how organizers form de novo from somatic adult tissues. Both extracellular matrix remodeling and caspase activation play a key role in this transition, acting as promoters of organizer formation in the vicinity of the wound. Their respective roles and the crosstalk between them just start to be deciphered. PMID:26970630

  10. 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 α-(p-chlorophenoxy) isobutyric acid (PCIB) during Brassica napus microspore embryogenesis. The results indicated de novo auxin synthesis after stress-induced microspore reprogramming and embryogenesis initiation, accompanying the first cell divisions. The progressive increase of auxin concentration during progression of embryogenesis correlated with the expression patterns of TAA1 and NIT2 genes of auxin biosynthetic pathways. Auxin was evenly distributed in early embryos, whereas in heart/torpedo embryos auxin was accumulated in apical and basal embryo regions. Auxin efflux carrier PIN1-like gene expression was induced in early multicellular embryos and increased at the globular/torpedo embryo stages. Inhibition of polar auxin transport (PAT) and action, by NPA and PCIB, impaired embryo development, indicating that PAT and auxin action are required for microspore embryo progression. NPA also modified auxin embryo accumulation patterns. These findings indicate that endogenous auxin biosynthesis, action and polar transport are required in stress-induced microspore reprogramming, embryogenesis initiation and progression. PMID:25907568

  11. Diethylnitrosamine-induced expression of germline-specific genes and pluripotency factors, including vasa and oct4, in medaka somatic cells.

    PubMed

    Shen, Jialing; Yokota, Shinpei; Yokoi, Hayato; Suzuki, Tohru

    2016-09-16

    Various methods have been developed to reprogram mammalian somatic cells into pluripotent cells as well as to directly reprogram somatic cells into other cell lineages. We are interested in applying these methods to fish, and here, we examined whether mRNA expression of germline-specific genes (vasa, nanos2, -3) and pluripotency factors (oct4, sox2, c-myc, nanog) is inducible in somatic cells of Japanese medaka (Oryzias latipes). We found that the expression of vasa is induced in the gut and regenerating fin by exposure to a carcinogen, diethylnitrosamine (DEN). Induction of vasa in the gut started on the 5th day of treatment with >50 ppm DEN. In addition, nanos2, -3, oct4, sox2, klf4, c-myc, and nanog were also expressed simultaneously in some vasa-positive gut and regenerating fin samples. Vasa-positive cells were detected by immunohistochemistry (IHC) in the muscle surrounding the gut and in the wound epidermis, blastema, and fibroblast-like cells in regenerating fin. In vasa:GFP transgenic medaka, green fluorescent protein (GFP) fluorescence appeared in the wound epidermis and fibroblast-like cells in the regenerating fin following DEN exposure, in agreement with the IHC data. Our data show that mRNA expression of genes relevant to germ cell specification and pluripotency can be induced in fish somatic cells by exposure to DEN, suggesting the possibility of efficient and rapid cell reprogramming of fish somatic cells. PMID:27514449

  12. Peer emotion socialization and somatic complaints in adolescents.

    PubMed

    Parr, Naomi J; Zeman, Janice; Braunstein, Kara; Price, Natalee

    2016-07-01

    Somatic symptoms tend to increase during early adolescence and although youth's social environments and emotional functioning play a role in somatic symptoms, few studies have examined mechanisms through which social interaction could influence youth's somatic wellbeing. Participants were 132 youth (61.6% girls, Mage = 12.61 years, 84.7% Caucasian) and their mothers. Reciprocated best-friend dyads participated in a video-taped problem discussion task to assess peer emotion socialization responses. Two supportive friend responses (i.e., emotion-focused, problem-focused) and two unsupportive responses (i.e., punitive, neglect) were examined. Mothers reported on their child's somatic complaints. Friends who provided emotion-focused, problem-focused, punitive, and neglect responses to their close friend's emotional disclosures had significantly fewer somatic symptoms. However, youth who received punitive responses to their emotional disclosures from their close friends had more somatic complaints. These findings provide initial evidence of a link between emotion socialization responses within close friendships and somatic complaints in early adolescence. PMID:27176784

  13. Somatic mutations in disorders with disrupted brain connectivity

    PubMed Central

    Lee, Jeong Ho

    2016-01-01

    Mutations occur during cell division in all somatic lineages. Because neurogenesis persists throughout human life, somatic mutations in the brain arise during development and accumulate with the aging process. The human brain consists of 100 billion neurons that form an extraordinarily intricate network of connections to achieve higher level cognitive functions. Due to this network architecture, perturbed neuronal functions are rarely restricted to a focal area; instead, they are often spread via the neuronal network to affect other connected areas. Although somatic diversity is an evident feature of the brain, the extent to which somatic mutations affect the neuronal structure and function and their contribution to neurological disorders associated with disrupted brain connectivity remain largely unexplored. Notably, recent reports indicate that brain somatic mutations can indeed play a critical role that leads to the structural and functional abnormalities of the brain observed in several neurodevelopmental disorders. Here, I review the extent and significance of brain somatic mutations and provide my perspective regarding these mutations as potential molecular lesions underlying relatively common conditions with disrupted brain connectivity. Moreover, I discuss emerging technical platforms that will facilitate the detection of low-frequency somatic mutations and validate the biological functions of the identified mutations in the context of brain connectivity. PMID:27282107

  14. Somatic mutations in disorders with disrupted brain connectivity.

    PubMed

    Lee, Jeong Ho

    2016-01-01

    Mutations occur during cell division in all somatic lineages. Because neurogenesis persists throughout human life, somatic mutations in the brain arise during development and accumulate with the aging process. The human brain consists of 100 billion neurons that form an extraordinarily intricate network of connections to achieve higher level cognitive functions. Due to this network architecture, perturbed neuronal functions are rarely restricted to a focal area; instead, they are often spread via the neuronal network to affect other connected areas. Although somatic diversity is an evident feature of the brain, the extent to which somatic mutations affect the neuronal structure and function and their contribution to neurological disorders associated with disrupted brain connectivity remain largely unexplored. Notably, recent reports indicate that brain somatic mutations can indeed play a critical role that leads to the structural and functional abnormalities of the brain observed in several neurodevelopmental disorders. Here, I review the extent and significance of brain somatic mutations and provide my perspective regarding these mutations as potential molecular lesions underlying relatively common conditions with disrupted brain connectivity. Moreover, I discuss emerging technical platforms that will facilitate the detection of low-frequency somatic mutations and validate the biological functions of the identified mutations in the context of brain connectivity. PMID:27282107

  15. Cognitive Mechanisms Reciprocally Transmit Vulnerability between Depressive and Somatic Symptoms

    PubMed Central

    Harding, Kaitlin A.; Murphy, Karly M.

    2015-01-01

    Despite high comorbidity between depressive and somatic symptoms, cognitive mechanisms that transmit vulnerability between symptom clusters are largely unknown. Dampening, positive rumination, and brooding are three cognitive predictors of depression, with rumination theoretically indicated as a transdiagnostic vulnerability through amplifying and diminishing affect in response to events. Specifically, the excess negative affect and lack of positive affect characteristic of depressive symptoms and underlying somatic symptoms may cause and be caused by cognitive responses to events. Therefore, the current study examined whether comorbidity between depressive and somatic symptoms may be explained by the cognitive mechanisms of dampening and positive rumination in response to positive events and brooding in response to negative events among adults (N = 321) across eight weeks of assessment. We hypothesized that greater dampening and brooding would reciprocally predict greater depressive and somatic symptoms, while greater positive rumination would reciprocally predict fewer depressive and somatic symptoms. Mediation analyses in AMOS 22 indicated that dampening and brooding mediated reciprocal pathways between depressive and somatic symptoms, but positive rumination did not. Findings propose dampening and brooding as mechanisms of the reciprocal relationship between depressive and somatic symptoms through diminishing positive affect and amplifying negative affect in response to positive and negative events. PMID:26783455

  16. 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

  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

    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. Regeneration of flax ( Linum usitatissimum L.) plants from anther culture and somatic tissue with increased resistance to Fusarium oxysporum.

    PubMed

    Rutkowska-Krause, I; Mankowska, G; Lukaszewicz, M; Szopa, J

    2003-09-01

    The aim of this study was to establish a protocol for the efficient production of flax plants of microspore origin. The results were compared to those obtained for plants regenerated from somatic explants from hypocotyls, cotyledons, leaves, stems and roots. All the plants obtained during the experiments were regenerated from callus that was grown for periods from a few weeks to a few months before the regeneration was achieved. Anther cultures were less effective in plant regeneration than somatic cell cultures. However, regenerants derived from anther cells showed valuable breeding features, including increased resistance to fungal wilt. The age of the donor plants and the season they grew in had a noticeable effect on their anther callusing and subsequent plant regeneration. Low temperature had a negative effect and dark pre-treatment a positive effect on callusing and plant regeneration. Different media were most effective for callus induction, shoot induction and rooting. For callus induction two carbon sources (2.5% sucrose and 2.5% glucose) were most effective; for shoots, only sucrose at lower concentration (2%) was effective. Rooting was most efficient in 1% sucrose and reduced (50%) mineral concentration in the medium. It was found that the length of in vitro cultivation significantly increases the ploidy and affects such features as regenerant morphological characteristics, petal colour, and resistance to Fusarium oxysporum-induced fungal wilt. The established plant regeneration system provides a basis for the creation of transgenic flax. PMID:12827441

  19. Cotyledonary somatic embryos of Pinus pinaster Ait. most closely resemble fresh, maturing cotyledonary zygotic embryos: biological, carbohydrate and proteomic analyses.

    PubMed

    Morel, Alexandre; Trontin, Jean-François; Corbineau, Françoise; Lomenech, Anne-Marie; Beaufour, Martine; Reymond, Isabelle; Le Metté, Claire; Ader, Kevin; Harvengt, Luc; Cadene, Martine; Label, Philippe; Teyssier, Caroline; Lelu-Walter, Marie-Anne

    2014-11-01

    Cotyledonary somatic embryos (SEs) of maritime pine are routinely matured for 12 weeks before being germinated and converted to plantlets. Although regeneration success is highly dependent on SEs quality, the date of harvesting is currently determined mainly on the basis of morphological features. This empirical method does not provide any accurate information about embryo quality with respect to storage compounds (proteins, carbohydrates). We first analyzed SEs matured for 10, 12 and 14 weeks by carrying out biological (dry weight, water content) and biochemical measurements (total protein and carbohydrate contents). No difference could be found between collection dates, suggesting that harvesting SEs after 12 weeks is appropriate. Cotyledonary SEs were then compared to various stages, from fresh to fully desiccated, in the development of cotyledonary zygotic embryos (ZEs). We identified profiles that were similar using hierarchical ascendant cluster analysis (HCA). Fresh and dehydrated ZEs could be distinguished, and SEs clustered with fresh ZEs. Both types of embryo exhibited similar carbohydrate and protein contents and signatures. This high level of similarity (94.5 %) was further supported by proteome profiling. Highly expressed proteins included storage, stress-related, late embryogenesis abundant and energy metabolism proteins. By comparing overexpressed proteins in developing and cotyledonary SEs or ZEs, some (23 proteins) could be identified as candidate biomarkers for the late, cotyledonary stage. This is the first report of useful generic protein markers for monitoring embryo development in maritime pine. Our results also suggest that improvements of SEs quality may be achieved if the current maturation conditions are refined. PMID:25115559

  20. 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

  1. Roles of gangliosides in mouse embryogenesis and embryonic stem cell differentiation

    PubMed Central

    Kwak, Dong Hoon; Seo, Byoung Boo; Chang, Kyu Tae

    2011-01-01

    Gangliosides have been suggested to play important roles in various functions such as adhesion, cell differentiation, growth control, and signaling. Mouse follicular development, ovulation, and luteinization during the estrous cycle are regulated by several hormones and cell-cell interactions. In addition, spermatogenesis in seminiferous tubules of adult testes is also regulated by several hormones, including follicle-stimulating hormone (FSH) and luteinizing hormone (LH) and cell-cell interactions. The regulation of these processes by hormones and cell-cell interactions provides evidence for the importance of surface membrane components, including gangliosides. During preimplantation embryo development, a mammalian embryo undergoes a series of cleavage divisions whereby a zygote is converted into a blastocyst that is sufficiently competent to be implanted in the maternal uterus and continue its development. Mouse embryonic stem (mES) cells are pluripotent cells derived from mouse embryo, specifically, from the inner cell mass of blastocysts. Differentiated neuronal cells are derived from mES cells through the formation of embryonic bodies (EBs). EBs recapitulate many aspects of lineage-specific differentiation and temporal and spatial gene expression patterns during early embryogenesis. Previous studies on ganglioside expression during mouse embryonic development (including during in vitro fertilization, ovulation, spermatogenesis, and embryogenesis) reported that gangliosides were expressed in both undifferentiated and differentiated (or differentiating) mES cells. In this review, we summarize some of the advances in our understanding of the functional roles of gangliosides during the stages of mouse embryonic development, including ovulation, spermatogenesis, and embryogenesis, focusing on undifferentiated and differentiated mES cells (neuronal cells). PMID:21654188

  2. Consequences of the recurrent MYD88(L265P) somatic mutation for B cell tolerance.

    PubMed

    Wang, James Q; Jeelall, Yogesh S; Beutler, Bruce; Horikawa, Keisuke; Goodnow, Christopher C

    2014-03-10

    MYD88(L265P) has recently been discovered as an extraordinarily frequent somatic mutation in benign monoclonal IgM gammopathy, Waldenström's macroglobulinemia, and diffuse large B cell lymphoma. In this study, we analyze the consequences for antigen-activated primary B cells of acquiring MYD88(L265P). The mutation induced rapid B cell division in the absence of exogenous TLR ligands and was inhibited by Unc93b1(3d) mutation and chloroquine or TLR9 deficiency, indicating continued dependence on upstream TLR9 activation. Proliferation and NF-κB activation induced by MYD88(L265P) were nevertheless rapidly countered by the induction of TNFAIP3, an NF-κB inhibitor frequently inactivated in MYD88(L265P)-bearing lymphomas, and extinguished by Bim-dependent apoptosis. MYD88(L265P) caused self-reactive B cells to accumulate in vivo only when apoptosis was opposed by Bcl2 overexpression. These results reveal checkpoints that fortify TLR responses against aberrant B cell proliferation in response to ubiquitous TLR and BCR self-ligands and suggest that tolerance failure requires the accumulation of multiple somatic mutations. PMID:24534189

  3. Global expression profiling reveals genetic programs underlying the developmental divergence between mouse and human embryogenesis

    PubMed Central

    2013-01-01

    Background Mouse has served as an excellent model for studying human development and diseases due to its similarity to human. Advances in transgenic and knockout studies in mouse have dramatically strengthened the use of this model and significantly improved our understanding of gene function during development in the past few decades. More recently, global gene expression analyses have revealed novel features in early embryogenesis up to gastrulation stages and have indeed provided molecular evidence supporting the conservation in early development in human and mouse. On the other hand, little information is known about the gene regulatory networks governing the subsequent organogenesis. Importantly, mouse and human development diverges during organogenesis. For instance, the mouse embryo is born around the end of organogenesis while in human the subsequent fetal period of ongoing growth and maturation of most organs spans more than 2/3 of human embryogenesis. While two recent studies reported the gene expression profiles during human organogenesis, no global gene expression analysis had been done for mouse organogenesis. Results Here we report a detailed analysis of the global gene expression profiles from egg to the end of organogenesis in mouse. Our studies have revealed distinct temporal regulation patterns for genes belonging to different functional (Gene Ontology or GO) categories that support their roles during organogenesis. More importantly, comparative analyses identify both conserved and divergent gene regulation programs in mouse and human organogenesis, with the latter likely responsible for the developmental divergence between the two species, and further suggest a novel developmental strategy during vertebrate evolution. Conclusions We have reported here the first genome-wide gene expression analysis of the entire mouse embryogenesis and compared the transcriptome atlas during mouse and human embryogenesis. Given our earlier observation that genes

  4. 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

  5. Constitutive heterochromatin reorganization during somatic cell reprogramming

    PubMed Central

    Fussner, Eden; Djuric, Ugljesa; Strauss, Mike; Hotta, Akitsu; Perez-Iratxeta, Carolina; Lanner, Fredrik; Dilworth, F Jeffrey; Ellis, James; Bazett-Jones, David P

    2011-01-01

    Induced pluripotent stem (iPS) cell reprogramming is a gradual epigenetic process that reactivates the pluripotent transcriptional network by erasing and establishing repressive epigenetic marks. In contrast to loci-specific epigenetic changes, heterochromatin domains undergo epigenetic resetting during the reprogramming process, but the effect on the heterochromatin ultrastructure is not known. Here, we characterize the physical structure of heterochromatin domains in full and partial mouse iPS cells by correlative electron spectroscopic imaging. In somatic and partial iPS cells, constitutive heterochromatin marked by H3K9me3 is highly compartmentalized into chromocentre structures of densely packed chromatin fibres. In contrast, chromocentre boundaries are poorly defined in pluripotent embryonic stem and full iPS cells, and are characterized by unusually dispersed 10 nm heterochromatin fibres in high Nanog-expressing cells, including pluripotent cells of the mouse blastocyst before differentiation. This heterochromatin reorganization accompanies retroviral silencing during conversion of partial iPS cells by MEK/GSK3 2i inhibitor treatment. Thus, constitutive heterochromatin is compacted in partial iPS cells but reorganizes into dispersed 10 nm chromatin fibres as the fully reprogrammed iPS cell state is acquired. PMID:21468033

  6. Dysphoria and somatization in Iranian culture.

    PubMed Central

    Pliskin, K L

    1992-01-01

    Iranians express dysphoria through an undifferentiated term called narahati, meaning depressed, ill at ease, nervous, inconvenienced, or anxious. People try masking this emotion or express it in specific ways nonverbally, such as sulking or not eating. Two other dysphoric affects, sadness and anger, are not masked. Because of the social conception of persons being emotionally sensitive, the expression of narahati is guarded: expressing it not only could show that one is socially vulnerable, it could also make another sensitive empathic person narahat. The body is also sensitive, but to the physical world. Physical health is maintained by balancing a diet of "hot" and "cold" foods and avoiding exposure to cold and moisture. With the social and cultural problems brought on by revolution, war, immigration, and accommodation to a new society, Iranian refugees experience changes in family, role, status, finances, language, and other sociocultural ways of being that cause them to feel narahat and to express it verbally, nonverbally, or through somatization. Understanding Iranian conceptions of emotional and physical sensitivity will help clinicians in treating Iranian patients. PMID:1413773

  7. Cytogenetic analysis of human somatic cell haploidization.

    PubMed

    Galat, V; Ozen, S; Rechitsky, S; Kuliev, A; Verlinsky, Y

    2005-02-01

    Despite recent interest in the derivation of female and male gametes through somatic cell nuclear transfer, there is still insufficient data on chromosomal analysis of these gametes resulting from haploidization, especially involving a human nuclear donor and recipient oocytes. The objective of this study was to investigate the fidelity of chromosomal separation during haploidization of human cumulus cells by in-vitro matured human enucleated MII oocytes. A total of 129 oocytes were tested 4-7, 8-14, or 15-21 h after nuclear transfer (NT) followed by electro-stimulation, resulting in 71.3% activation efficiency on average. Haploidization was documented by the formation of two separate groups of chromosomes, originating from either polar body/pronucleus (PB/PN), or only 2PN, which were tested by 5-colour FISH, or DNA analysis for copy number of chromosomes 13, 16, 18, 21, 22 and X. Two PN were formed more frequently than PB/PN, irrespective of incubation time. In agreement with recent reports on mouse oocytes, as many as 90.2% of the resulting haploid sets tested showed abnormal chromosome segregation, suggesting unsuitability of the resulting artificial gametes for practical application at the present time. PMID:15823223

  8. High-throughput Phenotyping of Lung Cancer Somatic Mutations.

    PubMed

    Berger, Alice H; Brooks, Angela N; Wu, Xiaoyun; Shrestha, Yashaswi; Chouinard, Candace; Piccioni, Federica; Bagul, Mukta; Kamburov, Atanas; Imielinski, Marcin; Hogstrom, Larson; Zhu, Cong; Yang, Xiaoping; Pantel, Sasha; Sakai, Ryo; Watson, Jacqueline; Kaplan, Nathan; Campbell, Joshua D; Singh, Shantanu; Root, David E; Narayan, Rajiv; Natoli, Ted; Lahr, David L; Tirosh, Itay; Tamayo, Pablo; Getz, Gad; Wong, Bang; Doench, John; Subramanian, Aravind; Golub, Todd R; Meyerson, Matthew; Boehm, Jesse S

    2016-08-01

    Recent genome sequencing efforts have identified millions of somatic mutations in cancer. However, the functional impact of most variants is poorly understood. Here we characterize 194 somatic mutations identified in primary lung adenocarcinomas. We present an expression-based variant-impact phenotyping (eVIP) method that uses gene expression changes to distinguish impactful from neutral somatic mutations. eVIP identified 69% of mutations analyzed as impactful and 31% as functionally neutral. A subset of the impactful mutations induces xenograft tumor formation in mice and/or confers resistance to cellular EGFR inhibition. Among these impactful variants are rare somatic, clinically actionable variants including EGFR S645C, ARAF S214C and S214F, ERBB2 S418T, and multiple BRAF variants, demonstrating that rare mutations can be functionally important in cancer. PMID:27478040

  9. Somatic treatments excluding psychopharmacology in obsessive- compulsive disorder: a review.

    PubMed

    Atmaca, Murad

    2013-06-01

    Somatic treatments other than psychotropic drugs are increasingly used in the patients with obsessive compulsive disorder (OCD), however there has been little systematic review of them. Therefore, the present review deals with a variety of somatic treatment methods excluding psychotropic drugs. A literature search was performed on the PubMed database from the beginning of 1980, to September 2012, for published English, Turkish and French-language articles of somatic treatment approaches (excluding psychopharmacological agents) in the treatment of OCD. The search was carried out by using some terms in detail. Afterwards, the obtained investigations on electroconvusive therapy (ECT), deep brain stimulation (DBS), neurosurgical methods and transcranial magnetic stimulation (TMS) were presented. Although psychopharmacological treatment and psychotherapeutic approaches are primary treatment modalities in the management of OCD, other somatic treatment options seem to be used as alternatives, especially for patients with treatmentresistant OCD. PMID:24032546

  10. 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

  11. [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.

  12. Chromatin remodeling in somatic cells injected into mature pig oocytes.

    PubMed

    Bui, Hong-Thuy; Van Thuan, Nguyen; Wakayama, Teruhiko; Miyano, Takashi

    2006-06-01

    We examined the involvement of histone H3 modifications in the chromosome condensation and decondensation of somatic cell nuclei injected into mature pig oocytes. Nuclei of pig granulosa cells were transferred into in vitro matured intact pig oocytes, and histone H3 phosphorylation, acetylation, and methylation were examined by immunostaining with specific antibodies in relation to changes in chromosome morphology. In the condensed chromosomes of pig oocytes at metaphase II, histone H3 was phosphorylated at serine 10 (H3-S10) and serine 28 (H3-S28), and methylated at lysine 9 (H3-K9), but was not acetylated at lysine 9, 14 and 18 (H3-K9, H3-K14 and H3-K18). During the first 2 h after nuclear transfer, a series of events were observed in the somatic nuclei: nuclear membrane disassembly; chromosome condensation to form a metaphase-like configuration; an increase in histone H3 phosphorylation levels (H3-S10 and H3-S28). Next, pig oocytes injected with nuclei of somatic cells were electroactivated and the chromosome morphology of oocytes and somatic cells was examined along with histone modifications. Generally, chromosomes of the somatic cells showed a similar progression of cell cycle stage to that of oocytes, through anaphase II- and telophase II-like stages then formed pronucleus-like structures, although the morphology of the spindles differed from that of oocyte spindles. The chromosomes of somatic cells also showed changes in histone H3 dephosphorylation and reacetylation, similar to oocytes. In contrast, histone H3 methylation (H3-K9) of somatic cell nuclei did not show any significant change after injection and electroactivation of the oocytes. These results suggest that nuclear remodeling including histone H3 phosphorylation and acetylation of injected somatic nuclei took place in the oocytes under regulation by the oocyte cytoplasm. PMID:16735543

  13. Teaching at the interface of dance science and somatics.

    PubMed

    Geber, Pamela; Wilson, Margaret

    2010-01-01

    This article introduces a combined scientific and somatic approach to teaching and learning about the body, and explains how it can be of benefit to dancers and dance educators. The study of the science of movement (kinesiology) and a somatic approach to teaching are initially defined and described as distinct entities; following this, a model for integration of the two is presented. The authors advocate for such a combination in order to enhance dancing. PMID:20507721

  14. Age-related somatic mutations in the cancer genome

    PubMed Central

    Milholland, Brandon; Auton, Adam; Suh, Yousin; Vijg, Jan

    2015-01-01

    Aging is associated with an increased risk of cancer, possibly in part because of an age-related increase in mutations in normal tissues. Due to their extremely low abundance, somatic mutations in normal tissues frequently escape detection. Tumors, as clonal expansions of single cells, can provide information about the somatic mutations present in these cells prior to tumorigenesis. Here, we used data from The Cancer Genome Atlas (TCGA), to systematically study the frequency and spectrum of somatic mutations in a total of 6,969 patients and 34 different tumor types as a function of the age of the patient. After using linear modeling to control for the age structure of different tumor types, we found that the number of identified somatic mutations increases exponentially with age. Using additional data from the literature, we found that accumulation of somatic mutations is associated with cell division rate, cancer risk and cigarette smoking, with the latter also associated with a distinct spectrum of mutations. Our results confirm that aging is associated with the accumulation of somatic mutations, and strongly suggest that the level of genome instability of normal cells, modified by both endogenous and environmental factors, is the main risk factor for cancer. PMID:26384365

  15. Preliminary study of a scale measuring depression and somatic symptoms.

    PubMed

    Hung, Ching-I; Weng, Li-Jen; Su, Yi-Jen; Liu, Chia-Yih

    2006-10-01

    This description concerns the development of a scale measuring depression and somatic symptoms and the selection of its items for a Taiwanese sample. 102 Taiwanese outpatients (28 men, 74 women) with major depressive disorder completed a 44-item preliminary scale. All had experienced a major depressive episode but had not been treated by antidepressants within the prior two weeks. The Hamilton Depression Rating Scale was administered to evaluate the validity of the Depression and Somatic Symptoms Scale (DSSS). Items, 12 for the Depression Subscale and 10 for the Somatic Subscale, were selected for the Depression and Somatic Symptoms Scale according to their frequency and their association with rated severity of depression and clinical practices. The mean Hamilton Depression score was 23.9 (SD = 5.2) versus 38.4 (SD = 11.3) for the total DSSS; means for the Depression subscale were 23.5 +/- 6.0 and the Somatic subscale 14.9 +/- 6.8. Cronbach alpha was .88 for the total DSSS, .78 for the Depression subscale, and .86 for the Somatic subscale. The Pearson correlation coefficient for the two scales was .59 (p <.01). The new scale had adequate internal consistency reliability and convergent validity. Much study is required to assess its structure, item characteristics, and in judging its applicability and limitations, and sensitivity to cultural differences in clinical settings. PMID:17153806

  16. 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...

  17. Early somatic embryo induction events in alfalfa callus cultures. [Medicago sativa

    SciTech Connect

    El-Bakry, A.A.; Hildebrand, D.F.

    1987-04-01

    High and low regenerating alfalfa Medicago sativa L. cv Regen S full sibs were isolated from a callus culture screen on modified Blaydes medium. The average number of embryos per ovary were thirty and zero for the high and low genotypes respectively after six weeks in culture. Proembryonic cell masses (4-8 celled) were observed after 4-5 days in culture and maximum meristematic activity was at 6-7 days in culture, for the high regenerating genotypes. Well formed globular embryos, both epidermal and subepidermal in origin, were observed after 2 weeks is culture. Samples in culture for 3, 6 and 14 days from the high and low regenerating genotypes were radiolabeled in vivo with /sup 35/S-methionine and run both on one and two dimension gels. The results will be discussed in relation to differences in proteins between the high and low regenerating genotypes at the stage of maximum meristematic activity (day 6) and differences occurring relative to the appearance of globular stage embryos (day 14) will be presented.

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

    SciTech Connect

    Yue, Xiao-shan; Fujishiro, Masako; Toyoda, Masashi; Akaike, Toshihiro; Ito, Yoshihiro

    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.

  19. 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

  20. Protein N-terminal acetylation is required for embryogenesis in Arabidopsis.

    PubMed

    Feng, Jinlin; Li, Ruiqi; Yu, Junya; Ma, Shuangshuang; Wu, Chunyan; Li, Yan; Cao, Ying; Ma, Ligeng

    2016-08-01

    Early embryonic development generates precursors of all major cell types in Arabidopsis. Among these precursors, the hypophysis divides asymmetrically to form the progenitors of the quiescent center and columella stem cells. A great deal has been learnt about the mechanisms that control the asymmetric division of the hypophysis and embryogenesis at the transcriptional level; however, no evidence of regulation at the co- or post-translational level has been reported. Here, we show that mutation of the catalytic subunit (Naa10) or auxiliary subunit (Naa15) of NatA, an N-terminal acetyltransferase that catalyzes protein N-terminal acetylation, produces an embryo-lethal phenotype. In addition, Naa10 and Naa15 were found to interact physically in planta Further analysis revealed that the observed embryonic patterning defects started at the early globular stage and that the asymmetric division of the hypophysis was irregular; thus, no quiescent center progenitor cells were generated in naa10 and naa15 embryos. We further observed that the polar distributions of auxin and its efflux carrier PIN1 were disturbed in naa10 embryos. Our results suggest that NatA is required for asymmetric division of the hypophysis and early embryonic patterning in Arabidopsis, and provides a link between protein N-terminal acetylation and embryogenesis in plants. PMID:27385766

  1. 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-β/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-β/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

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

    PubMed

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

    1995-11-01

    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. PMID:11539283

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

    PubMed

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

    2013-05-01

    Mitochondrial DNA (mtDNA) content is thought to remain stable over the preimplantation period of human embryogenesis that is, therefore, suggested to be entirely dependent on ooplasm mtDNA capital. We have explored the impact of two disease-causing mutations [m.3243A>G myopathy, encephalopathy, lactic acidosis and stroke-like syndrome (MELAS) and m.8344A>G myoclonic epilepsy associated with ragged-red fibers (MERRF)] on mtDNA amounts in human oocytes and day 4-5 preimplantation embryos. The mtDNA amount was stable in MERRF and control materials, whereas gradually increasing from the germinal vesicle of oogenesis to the blastocyst stage of embryogenesis in MELAS cells, MELAS embryos carrying ∼3-fold higher mtDNA amount than control embryos (P = 0.0003). A correlation between mtDNA copy numbers and mutant loads was observed in MELAS embryos (R(2) = 0.42, P < 0.0013), suggestive of a compensation for the respiratory chain defect resulting from high mutation levels. These results suggest that mtDNA can replicate in early embryos and emphasize the need for sufficient amount of wild-type mtDNA to sustain embryonic development in humans. PMID:23390135

  4. Cellular dynamics during early barley pollen embryogenesis revealed by time-lapse imaging

    PubMed Central

    Daghma, Diaa Eldin S.; Hensel, Goetz; Rutten, Twan; Melzer, Michael; Kumlehn, Jochen

    2014-01-01

    Plants display a remarkable capacity for cellular totipotency. An intriguing and useful example is that immature pollen cultured in vitro can pass through embryogenic development to form haploid or doubled haploid plants. However, a lack of understanding the initial mechanisms of pollen embryogenesis hampers the improvement and more effective and widespread employment of haploid technology in plant research and breeding. To investigate the cellular dynamics during the onset of pollen embryogenesis, we used time-lapse imaging along with transgenic barley expressing nuclear localized Green Fluorescent Protein. The results enabled us to identify nine distinct embryogenic and non-embryogenic types of pollen response to the culture conditions. Cell proliferation in embryogenic pollen normally started via a first symmetric mitosis (54.3% of pollen observed) and only rarely did so via asymmetric pollen mitosis I (4.3% of pollen observed). In the latter case, proliferation generally originated from the vegetative-like cell, albeit the division of the generative-like cell was observed in few types of pollen. Under the culture conditions used, fusion of cell nuclei was the only mechanism of genome duplication observed. PMID:25538715

  5. Changes in lipid droplet localization during embryogenesis of the silkworm, Bombyx mori.

    PubMed

    Yamahama, Yumi; Seno, Keiji; Hariyama, Takahiko

    2008-06-01

    Lipid droplets are considered one of the most important energy sources in lepidopteran eggs during late embryogenesis, but the process of their incorporation into the embryo is as yet unknown. The present study focused on the process of transition of lipid droplets from the extraembryonic yolk to the embryo of the silkworm Bombyx mori, using morphological and biochemical approaches. The morphological study revealed that the incorporation of lipid droplets from the extraembryonic yolk into the embryo occurs at three points and in three different ways during the development of the embryo. Some lipid droplets were translocated directly from the extraembryonic yolk to the embryo before the blastokinesis stage. However, the majority of lipid droplets together with the other components of the extraembryonic yolk were incorporated in the embryo via both morphogenetic inclusion during dorsal closure and ingestion of the extraembyonic yolk by the developing caterpillar prior to hatching. Similar results were obtained from the biochemical study. Thus, we propose that there are three steps in the incorporation of lipid droplets from the extraembryonic yolk into the embryo. In addition, morphological and biochemical data concerning the total amount of lipid droplets in the egg suggested that lipid droplets were mainly consumed during late embryogenesis, seeming to synchronize with tracheal development. PMID:18624568

  6. Global analyses of mRNA translational control during early Drosophila embryogenesis

    PubMed Central

    Qin, Xiaoli; Ahn, Soyeon; Speed, Terence P; Rubin, Gerald M

    2007-01-01

    Background In many animals, the first few hours of life proceed with little or no transcription, and developmental regulation at these early stages is dependent on maternal cytoplasm rather than the zygotic nucleus. Translational control is critical for early Drosophila embryogenesis and is exerted mainly at the gene level. To understand post-transcriptional regulation during Drosophila early embryonic development, we used sucrose polysomal gradient analyses and GeneChip analysis to illustrate the translation profile of individual mRNAs. Results We determined ribosomal density and ribosomal occupancy of over 10,000 transcripts during the first ten hours after egg laying. Conclusion We report the extent and general nature of gene regulation at the translational level during early Drosophila embryogenesis on a genome-wide basis. The diversity of the translation profiles indicates multiple mechanisms modulating transcript-specific translation. Cluster analyses suggest that the genes involved in some biological processes are co-regulated at the translational level at certain developmental stages. PMID:17448252

  7. 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.

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

    PubMed

    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

  9. Protein N-terminal acetylation is required for embryogenesis in Arabidopsis

    PubMed Central

    Feng, Jinlin; Li, Ruiqi; Yu, Junya; Ma, Shuangshuang; Wu, Chunyan; Li, Yan; Cao, Ying; Ma, Ligeng

    2016-01-01

    Early embryonic development generates precursors of all major cell types in Arabidopsis. Among these precursors, the hypophysis divides asymmetrically to form the progenitors of the quiescent center and columella stem cells. A great deal has been learnt about the mechanisms that control the asymmetric division of the hypophysis and embryogenesis at the transcriptional level; however, no evidence of regulation at the co- or post-translational level has been reported. Here, we show that mutation of the catalytic subunit (Naa10) or auxiliary subunit (Naa15) of NatA, an N-terminal acetyltransferase that catalyzes protein N-terminal acetylation, produces an embryo-lethal phenotype. In addition, Naa10 and Naa15 were found to interact physically in planta. Further analysis revealed that the observed embryonic patterning defects started at the early globular stage and that the asymmetric division of the hypophysis was irregular; thus, no quiescent center progenitor cells were generated in naa10 and naa15 embryos. We further observed that the polar distributions of auxin and its efflux carrier PIN1 were disturbed in naa10 embryos. Our results suggest that NatA is required for asymmetric division of the hypophysis and early embryonic patterning in Arabidopsis, and provides a link between protein N-terminal acetylation and embryogenesis in plants. PMID:27385766

  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. 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

  12. LEAFY COTYLEDON1 Is an Essential Regulator of Late Embryogenesis and Cotyledon Identity in Arabidopsis.

    PubMed Central

    West, MAL.; Yee, K. M.; Danao, J.; Zimmerman, J. L.; Fischer, R. L.; Goldberg, R. B.; Harada, J. J.

    1994-01-01

    LEAFY COTYLEDON1 (LEC1) is an embryo defective mutation that affects cotyledon identity in Arabidopsis. Mutant cotyledons possess trichomes that are normally a leaf trait in Arabidopsis, and the cellular organization of these organs is intermediate between that of cotyledons and leaves from wild-type plants. We present several lines of evidence that indicate that the control of late embryogenesis is compromised by the mutation. First, mutant embryos are desiccation intolerant, yet embryos can be rescued before they dry to yield homozygous recessive plants that produce defective embryos exclusively. Second, although many genes normally expressed during embryonic development are active in the mutant, at least one maturation phase-specific gene is not activated. Third, the shoot apical meristem is activated precociously in mutant embryos. Fourth, in mutant embryos, several genes characteristic of postgerminative development are expressed at levels typical of wild-type seedlings rather than embryos. We conclude that postgerminative development is initiated prematurely and that embryonic and postgerminative programs operate simultaneously in mutant embryos. The pleiotropic effects of the mutation indicate that the LEC1 gene plays a fundamental role in regulating late embryogenesis. The role of LEC1 and its relationship to other genes involved in controlling late embryonic development are discussed. PMID:12244233

  13. Lateral congenital anomalies of the pharyngeal apparatus: part I. Normal developmental anatomy (embryogenesis) for the surgeon.

    PubMed

    Mirilas, Petros

    2011-09-01

    Knowledge of the embryogenesis of the pharyngeal apparatus is the only means of understanding the "architecture" of the neck. The embryonic pharynx (which includes future oral and nasal cavities) is a much more extensive area than the adult pharynx. The main feature of the developing pharynx is a series of arches, internal pouches, and external clefts, which together comprise the pharyngeal apparatus. This structure is associated with other developing splanchna of the neck, e.g., the thyroid and parathyroid glands, tonsils, and thymus. Within each of the pharyngeal arches are the developing aortic arches and, specific for each arch, cranial nerves. The complex relations of the mesenchymal derivatives of arches (muscles, cartilage, bones) with the neurovascular bundles within each arch are presented and explained. The pharyngeal apparatus undergoes dramatic transformations: pouches and clefts disappear without interruption (interruption would produce gills and support the misnomer "branchial apparatus"). In addition, in the lateroventral neck, somites migrate to produce other muscles such as sternocleidomastoid and trapezius innervated by spinal nerves. Lateral congenital anomalies largely rely on persistence of a cleft/and or pouch or communication between the two. Their tracts have a "crooked" course among other entities generated by alterations that take place during embryogenesis. PMID:21944634

  14. Genotoxic effects of bisphenol A on somatic cells of female mice, alone and in combination with X-rays.

    PubMed

    Gajowik, Aneta; Radzikowska, Joanna; Dobrzyńska, Małgorzata M

    2013-10-01

    Bisphenol A (BPA), a monomer used in the manufacture of epoxy, polycarbonate, and polystyrene resins, is a xenoestrogen present in many consumer products. We investigated the effects of 2-week exposure to BPA, either alone or in combination with X-rays, on the induction of DNA damage in somatic cells of female mice in vivo. The micronucleus and alkaline comet assays were used to evaluate genotoxicity. BPA induced DNA strand breaks in lung cells but not in bone marrow lymphocytes, liver, kidney, or spleen cells. Induction of micronuclei was observed only in polychromatic reticulocytes of peripheral blood. Levels of damage following combination exposure to ionizing radiation plus BPA depended on tissue, assay, and time. PMID:23954285

  15. Pituitary Volumes Are Reduced in Patients with Somatization Disorder

    PubMed Central

    Yildirim, Hanefi; Sirlier, Burcu; Kayali, Alperen

    2012-01-01

    Objective Despite of the suggested physiological relationship between somatoform disorder and disturbances in HPA axis function no volumetric study of pituitary volumes in somatization disorder has been carried out. Therefore, we aimed to use structural MRI to evaluate the pituitary volumes of the patients with somatization disorder. Methods Eighteen female patients with somatization disorder according to DSM-IV and same number of healthy controls were included into the study. All subjects were scanned using a 1.5-T General Electric (GE; Milwaukee, USA) scanner. Pituitary volume measurements were determined by using manuallly tracings according to standard antomical atlases. Results It was found significantly smaller pituitary volumes of the whole group of somatization patients compared to healthy (t=-3.604, p=0.001). ANCOVA predicting pituitary volumes demonstrated a significant main effect of diagnostic group (F=13.530, p<0.001) but TBV (F=1.924, p>0.05) or age (F=1.159, p>0.05). It was determined that there was no significant correlation between smaller pituitary volumes and the duration of illness (r=0.16, p>0.05) in the patient group. Conclusion In conclusion, we suggest that the patients with somatization disorder might have significantly smaller pituitary volumes compared to healthy control subjects. PMID:22993528

  16. Brain somatic mutations: the dark matter of psychiatric genetics?

    PubMed

    Insel, T R

    2014-02-01

    Although inherited DNA sequences have a well-demonstrated role in psychiatric disease risk, for even the most heritable mental disorders, monozygotic twins are discordant at a significant rate. The genetic variation associated with mental disorders has heretofore been based on the search for rare or common variation in blood cells. This search is based on the premise that every somatic cell shares an identical DNA sequence, so that variation found in lymphocytes should reflect variation present in brain cells. Evidence from the study of cancer cells, stem cells and now neurons demonstrate that this premise is false. Somatic mutation is common in human cells and has been implicated in a range of diseases beyond cancer. The exuberant proliferation of cortical precursors during fetal development provides a likely environment for somatic mutation in neuronal and glial lineages. Studies of rare neurodevelopmental disorders, such as hemimegencephaly, demonstrate somatic mutations in affected cortical cells that cannot be detected in unaffected parts of the brain or in peripheral cells. This perspective argues for the need to investigate somatic variation in the brain as an explanation of the discordance in monozygotic twins, a proximate cause of mental disorders in individuals with inherited risk, and a potential guide to novel treatment targets. PMID:24342990

  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. Developmental regulation of neuroligin genes in Japanese rice fish (oryzias latipes) embryogenesis maintains the rhythym during ethanol-in

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although prenatal alcohol exposure is the potential cause of fetal alcohol spectrum disorder (FASD) in humans, the molecular mechanism(s) of FASD is yet unknown. We have used Japanese rice fish (Oryzias latipes) embryogenesis as an animal model of FASD and reported that this model has effectively ge...

  19. Molecular characterization of zebrafish embryogenesis via DNA microarrays and multiplatform time course metabolomics studies.

    PubMed

    Soanes, Kelly H; Achenbach, John C; Burton, Ian W; Hui, Joseph P M; Penny, Susanne L; Karakach, Tobias K

    2011-11-01

    One of the greatest strengths of "-omics" technologies is their ability to capture a molecular snapshot of multiple cellular processes simultaneously. Transcriptomics, proteomics, and metabolomics have, individually, been used in wide-ranging studies involving cell lines, tissues, model organisms, and human subjects. Nonetheless, despite the fact that their power lies in the global acquisition of parallel data streams, these methods continue to be employed separately. We highlight work done to merge transcriptomics and metabolomics technologies to study zebrafish (Danio rerio) embryogenesis. We combine information from three bioanalytical platforms, that is, DNA microarrays, (1)H nuclear magnetic resonance ((1)H NMR), and mass spectrometry (MS)-based metabolomics, to identify and provide insights into the organism's developmental regulators. We apply a customized approach to the analysis of such time-ordered measurements to provide temporal profiles that depict the modulation of metabolites and gene transcription. Initially, the three data sets were analyzed individually but later they were fused to highlight the advantages gained through such an integrated approach. Unique challenges posed by fusion of such data are discussed given differences in the measurement error structures, the wide dynamic range for the molecular species, and the analytical platforms used to measure them (i.e., fluorescence ratios, NMR, and MS intensities). Our data analysis reveals that changes in transcript levels at specific developmental stages correlate with previously published data with over 90% accuracy. In addition, transcript profiles exhibited trends that were similar to the accumulation of metabolites over time. Profiles for metabolites such as choline-like compounds (Trimethylamine-N-oxide, phosphocholine, betaine), creatinine/creatine, and other metabolites involved in energy metabolism exhibited a steady increase from 15 hours post fertilization (hpf) to 48 hpf. Other

  20. E3 ubiquitin ligases promote progression of differentiation during C. elegans embryogenesis.

    PubMed

    Du, Zhuo; He, Fei; Yu, Zidong; Bowerman, Bruce; Bao, Zhirong

    2015-02-15

    Regulated choice between cell fate maintenance and differentiation provides decision points in development to progress toward more restricted cell fates or to maintain the current one. Caenorhabditis elegans embryogenesis follows an invariant cell lineage where cell fate is generally more restricted upon each cell division. EMS is a progenitor cell in the four-cell embryo that gives rise to the endomesoderm. We recently found that when ubiquitin-mediated protein degradation is compromised, the anterior daughter of EMS, namely MS, reiterates the EMS fate. This observation demonstrates an essential function of ubiquitin-mediated protein degradation in driving the progression of EMS-to-MS differentiation. Here we report a genome-wide screen of the ubiquitin pathway and extensive lineage analyses. The results suggest a broad role of E3 ligases in driving differentiation progression. First, we identified three substrate-binding proteins for two Cullin-RING ubiquitin ligase (CRL) E3 complexes that promote the progression from the EMS fate to MS, namely LIN-23/β-TrCP and FBXB-3 for the CRL1/SCF complex and ZYG-11/ZYG-11B for the CRL2 complex. Genetic analyses suggest these E3 ligases function through a multifunctional protein OMA-1 and the endomesoderm lineage specifier SKN-1 to drive differentiation. Second, we found that depletion of components of the CRL1/SCF complex induces fate reiteration in all major founder cell lineages. These data suggest that regulated choice between self-renewal and differentiation is widespread during C. elegans embryogenesis as in organisms with regulative development, and ubiquitin-mediated protein degradation drives the choice towards differentiation. Finally, bioinformatic analysis of time series gene expression data showed that expression of E3 genes is transiently enriched during time windows of developmental stage transitions. Transcription factors show similar enrichment, but not other classes of regulatory genes. Based on these

  1. E3 ubiquitin ligases promote progression of differentiation during C. elegans embryogenesis

    PubMed Central

    Du, Zhuo; He, Fei; Yu, Zidong; Bowerman, Bruce; Bao, Zhirong

    2014-01-01

    Regulated choice between cell fate maintenance and differentiation provides decision points in development to progress toward more restricted cell fates or to maintain the current one. C. elegans embryogenesis follows an invariant cell lineage where cell fate is generally more restricted upon each cell division. EMS is a progenitor cell in the four-cell embryo that gives rise to the endomesoderm. We recently found that when ubiquitin-mediated protein degradation is compromised, the anterior daughter of EMS, namely MS, reiterates the EMS fate. This observation demonstrates an essential function of ubiquitin-mediated protein degradation in driving the progression of EMS-to-MS differentiation. Here we report a genome-wide screen of the ubiquitin pathway and extensive lineage analyses. The results suggest a broad role of E3 ligases in driving differentiation progression. First, we identified three substrate-binding proteins for two CRL (Cullin-RING ubiquitin Ligase) E3 complexes that promote the progression from the EMS fate to MS, namely LIN-23/β-TrCP and FBXB-3 for the CRL1/SCF complex and ZYG-11/ZYG-11B for the CRL2 complex. Genetic analyses suggest these E3 ligases function through a multifunctional protein OMA-1 and the endomesoderm lineage specifier SKN-1 to drive differentiation. Second, we found that depletion of components of the CRL1/SCF complex induces fate reiteration in all major founder cell lineages. These data suggest that regulated choice between self-renewal and differentiation is widespread during C. elegans embryogenesis as in organisms with regulative development, and ubiquitin-mediated protein degradation drives the choice towards differentiation. Finally, bioinformatic analysis of time series gene expression data showed that expression of E3 genes is transiently enriched during time windows of developmental stage transitions. Transcription factors show similar enrichment, but not other classes of regulatory genes. Based on these findings we

  2. Bovine ooplasm partially remodels primate somatic nuclei following somatic cell nuclear transfer.

    PubMed

    Wang, Kai; Beyhan, Zeki; Rodriguez, Ramon M; Ross, Pablo J; Iager, Amy E; Kaiser, German G; Chen, Ying; Cibelli, Jose B

    2009-03-01

    Interspecies somatic cell nuclear transfer (iSCNT) has the potential to become a useful tool to address basic questions about the nucleus-cytoplasm interactions between species. It has also been proposed as an alternative for the preservation of endangered species and to derive autologous embryonic stem cells. Using chimpanzee/ bovine iSCNT as our experimental model we studied the early epigenetic events that take place soon after cell fusion until embryonic genome activation (EGA). Our analysis suggested partial EGA in iSCNT embryos at the eight-cell stage, as indicated by Br-UTP incorporation and expression of chimpanzee embryonic genes. Oct4, Stella, Crabp1, CCNE2, CXCL6, PTGER4, H2AFZ, c-MYC, KLF4, and GAPDH transcripts were expressed, while Nanog, Glut1, DSC2, USF2, Adrbk1, and Lin28 failed to be activated. Although development of iSCNT embryos did not progress beyond the 8- to 16-cell stage, chromatin remodeling events, monitored by H3K27 methylation, H4K5 acetylation, and global DNA methylation, were similar in both intra- and interspecies SCNT embryos. However, bisulfite sequencing indicated incomplete demethylation of Oct4 and Nanog promoters in eight-cell iSCNT embryos. ATP production levels were significantly higher in bovine SCNT embryos than in iSCNT embryos, TUNEL assays did not reveal any difference in the apoptotic status of the nuclei from both types of embryos. Collectively, our results suggest that bovine ooplasm can partially remodel chimpanzee somatic nuclei, and provides insight into some of the current barriers iSCNT must overcome if further embryonic development is to be expected. PMID:19196039

  3. Neuronal generation from somatic stem cells: current knowledge and perspectives on the treatment of acquired and degenerative central nervous system disorders.

    PubMed

    Corti, S; Locatelli, F; Strazzer, S; Guglieri, M; Comi, G P

    2003-06-01

    Stem cell transplantation through cell replacement or as vector for gene delivery is a potential strategy for the treatment of neurodegenerative diseases. Several studies have reported the transdifferentiation of different somatic stem cells into neurons in vitro or after transplantation into animal models. This observation has pointed out the perspective of using an ethical and accessible cell source to "replace" damaged neurons or provide support to brain tissue. However, recent findings such as the cell fusion phenomenon have raised some doubts about the real existence of somatic stem cell plasticity. In this review, we will discuss current evidence and controversial issues about the neuroneogenesis from various sources of somatic cells focusing on the techniques of isolation, expansion in vitro as well as the inductive factors that lead to transdifferentiation in order to identify the factors peculiar to this process. The morphological, immunochemical, and physiological criteria to correctly judge whether the neuronal transdifferentation occurred are critically presented. We will also discuss the transplantation experiments that were done in view of a possible clinical therapeutic application. Animal models of stroke, spinal cord and brain trauma have improved with Mesenchymal Stem Cells or Bone Marrow transplantation. This improvement does not seem to depend on the replacement of the lost neurons but may be due to increased expression levels of neurotrophic factors, thus suggesting a beneficial effect of somatic cells regardless of transdifferentiation. Critical understanding of available data on the mechanisms governing the cell fate reprogramming is a necessary achievement toward an effective cell therapy. PMID:12762483

  4. Somatic cells count in cow's bulk tank milk.

    PubMed

    Olechnowicz, Jan; Jaśkowski, Jedrzej M

    2012-06-01

    The objective of this study was therefore to present factors affecting somatic cell counts in bovine bulk milk as a result of intramammary infections as well as non-infectious factors. The paper presents also the impact of on-farm management practices on the level of bulk milk somatic cell counts and presents quality indicators in bulk tank milk. At the farm level bulk milk bacterial infection takes place through three main sources: bacterial contamination from the external surface of the udder and teats, from the surface of the milking equipment, and from mastitis microorganisms within the udder. The threshold of 200,000 cells/ml identifies bacteriological negative quarters of the udder. The counts of mammary pathogens in bulk tank milk are relatively low, on average not exceeding 1,000 cfu/ml. Environmental pathogens predominate in bulk tank milk samples with somatic cells count <300 × 10(3) ml. PMID:22230979

  5. 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

  6. Dynamics and regulation of bulk milk somatic cell counts.

    PubMed Central

    Schukken, Y H; Weersink, A; Leslie, K E; Martin, S W

    1993-01-01

    Somatic cell count (SCC) in milk is inversely related to dairy cow productivity and milk quality. In an effort to improve product quality, and indirectly farm productivity, regulatory limits on somatic cell counts have been established by many of the major dairy producing countries. The purpose of this paper was to assess the impact of regulations on bulk milk somatic cell counts in Ontario and to assist producers in meeting regulatory limits through development of prediction models. Through the use of a transfer function model, provincial SCC was found to have dropped by approximately 60,000 as a result of the reduction program. Limits of the regulatory program, seasonality and herd characteristics were found through time series cross-sectional models to have an impact on prediction of SCC at the farm level, but the major influence was historical SCC levels. PMID:8490807

  7. [Somatic complaints, mood states, and emotional awareness in adolescents].

    PubMed

    Rieffe, Carolien; Villanueva, Lidón; Adrián, Juan E; Górriz, Ana B

    2009-08-01

    Health complaints are a common problem in adolescents, but a medical cause can only be found in few cases. Therefore, increasing attention is paid to psychological factors that might be related. Two areas of emotional functioning are frequently referred to in this respect: negative mood and emotional awareness. In this study, we examined whether emotional awareness contributes uniquely to the prediction of somatic complaints over and above negative mood. Self-report questionnaires of somatic complaints, mood states, and emotional awareness were completed in class by 441 adolescents, between 13 and 15 years old. Results showed that emotional awareness only presents a limited unique contribution to the prediction of somatic complaints. This contribution is moderated by mood states, except for two aspects of emotional awareness: bodily awareness of emotions and attending to others' emotions. This strengthens the hypothesis that emotional awareness precedes affective states, which, in turn, have an effect on youngsters' health perceptions. PMID:19622329

  8. The Great Recession, Somatic Symptomatology and Alcohol Use and Abuse

    PubMed Central

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

    2012-01-01

    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

  9. 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

  10. 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

  11. 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

  12. The role of CYP26 enzymes in defining appropriate retinoic acid exposure during embryogenesis.

    PubMed

    Pennimpede, Tracie; Cameron, Don A; MacLean, Glenn A; Li, Hui; Abu-Abed, Suzan; Petkovich, Martin

    2010-10-01

    Retinoic acid (RA) is a pleiotropic derivative of vitamin A, or retinol, which is responsible for all of the bioactivity associated with this vitamin. The teratogenic influences of vitamin A deficiency and excess RA in rodents were first observed more than 50 years ago. Efforts over the last 15-20 years have refined these observations by defining the molecular mechanisms that control RA availability and signaling during murine embryonic development. This review will discuss our current understanding of the role of RA in teratogenesis, with specific emphasis on the essential function of the RA catabolic CYP26 enzymes in preventing teratogenic consequences caused by uncontrolled distribution of RA. Particular focus will be paid to the RA-sensitive tissues of the caudal and cranial regions, the limb, and the testis, and how genetic mutation of factors controlling RA distribution have revealed important roles for RA during embryogenesis. PMID:20842651

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

    PubMed

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

    2015-08-15

    Embryogenesis is the coordinated assembly of tissues during morphogenesis through changes in individual cell behaviors and collective cell movements. Dynamic imaging, combined with quantitative analysis, is ideal for investigating fundamental questions in developmental biology involving cellular differentiation, growth control and morphogenesis. However, a reliable amniote model system that is amenable to the rigors of extended, high-resolution imaging and cell tracking has been lacking. To address this shortcoming, we produced a novel transgenic quail that ubiquitously expresses nuclear localized monomer cherry fluorescent protein (chFP). We characterize the expression pattern of chFP and provide concrete examples of how Tg(PGK1:H2B-chFP) quail can be used to dynamically image and analyze key morphogenetic events during embryonic stages X to 11. PMID:26209648

  14. Transcriptomic Analysis Brings New Insight into the Biological Role of the Prion Protein during Mouse Embryogenesis

    PubMed Central

    Khalifé, Manal; Young, Rachel; Passet, Bruno; Halliez, Sophie; Vilotte, Marthe; Jaffrezic, Florence; Marthey, Sylvain; Béringue, Vincent; Vaiman, Daniel; Le Provost, Fabienne; Laude, Hubert; Vilotte, Jean-Luc

    2011-01-01

    The biological function of the Prion protein remains largely unknown but recent data revealed its implication in early zebrafish and mammalian embryogenesis. To gain further insight into its biological function, comparative transcriptomic analysis between FVB/N and FVB/N Prnp knockout mice was performed at early embryonic stages. RNAseq analysis revealed the differential expression of 73 and 263 genes at E6.5 and E7.5, respectively. The related metabolic pathways identified in this analysis partially overlap with those described in PrP1 and PrP2 knockdown zebrafish embryos and prion-infected mammalian brains and emphasize a potentially important role for the PrP family genes in early developmental processes. PMID:21858045

  15. [Effect of several inhibitors of atmospheric metal corrosion (amines of the polymethylene series) on embryogenesis].

    PubMed

    Bariliak, I R; Paustovskaia, V V; Torbin, V F

    1978-01-01

    The influence of some polymethylene amines (inhibitors protecting metals from atmospheric corrosion) on the generative function in general and on the embryogenesis in particular was studied. Such inhibitors as MCDA-II (dicyclohexylamine salt dissolving in oil), HDA (dicyclohexylamine nitrate) and M-I (cyclohexylamine salt dissolving in oil) were investigated by intraorganic injection during the whole course of gestation (21 days), 2 and 4 months. The compounds in question were stated to possess a pronounced gonado- and embryotoxic effect depending on the dose and chemical composition of the substance. The least active was M-I inhibitor. Doses not affecting rat gonades were: for HDA--0.825 mg/kg, MCDA-II--4.7 mg/kg, M-I--34.9 mg/kg; their embryonic effects were 0.54, 2.35 and 349 mg/kg respectively. PMID:646657

  16. 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.

  17. Coordinated Metabolic Transitions During Drosophila Embryogenesis and the Onset of Aerobic Glycolysis

    PubMed Central

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

    2014-01-01

    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 α-ketoglutarate. We also find that genes involved in lipid breakdown and β-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

  18. 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

  19. Thermal manipulations of turkey embryos: The effect on thermoregulation and development during embryogenesis.

    PubMed

    Piestun, Y; Zimmerman, I; Yahav, S

    2015-02-01

    Previous studies conducted on meat-type chickens in our laboratory showed that thermal manipulations (TMS:) of the embryo during the time window of the hypothalamus-hypophysis-thyroid axis development and maturation significantly reduced the metabolic rates of the embryo and the chicken, improving the posthatch feed conversion rate (FCR:). The aim of the present study was to investigate the effect of intermittent TMs during turkey embryogenesis on embryo development. Fertile turkey eggs were divided into three treatments: control; 6H--with TM by elevation of temperature and RH by 1.7°C and 9%, respectively, above the control conditions for 6 h/d, from E10 through E22, i.e., 240 through 552 h of incubation; and 12H--with TM as above, for 12 h/d, during the same time period. From E0 through E10 and from E23 onward all eggs were incubated under control conditions. The embryo growth rate was not negatively affected by TM. During TM eggshell temperature, the embryonic heart rate and oxygen consumption were elevated by the manipulation while the embryos were in their ectothermic phase. However, by the end of the TM period and until hatch (the endothermic phase) these parameters were significantly lower in both TM treatments than in the control, indicating a lower metabolic rate and heat production. The TM embryos hatched approximately 10 h earlier than the controls, without any negative effects on chick body weight or hatchability. Nevertheless, TM treatments resulted in a higher proportion of chicks with unhealed navels. Body temperature at hatch was significantly lower in the TM chicks than in the controls, suggesting lower heat production and metabolic rate, which might affect the energy requirements for posthatch maintenance. It was concluded that TM during turkey embryogenesis might have altered the thermoregulatory set point, and thus lowered the embryo metabolic rate, which might have a long-lasting posthatch effect. PMID:25630674

  20. Disruption of Circulation by Ethanol Promotes Fetal Alcohol Spectrum Disorder (FASD) in Medaka (Oryzias latipes) Embryogenesis

    PubMed Central

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

    2008-01-01

    Japanese medaka (Oryzias latipes) embryos exposed to ethanol have developed craniofacial, cardiovascular and skeletal defects which can be compared with the phenotypic features of fetal alcohol spectrum disorder (FASD) observed in human. The present experiment was designed to show that the disruption in circulation by ethanol during embryogenesis is a potential cause of FASD. Fertilized eggs were exposed to ethanol (0, 100 and/or 400 mM) for 24 or 48 h at various developmental stages (Iwamatsu stages 4–30) and were analyzed at 6 day post fertilization (dpf). It was observed that controls and the embryos exposed to 100 mM ethanol were in circulating state; however, a significant number of embryos of stages 4–24 exposed to 400 mM ethanol had disrupted circulation. Compared to controls, protein and RNA contents were significantly reduced in non-circulating embryos. Lipid peroxidation (LPO) analysis was made at 3, 6, 24, 48, 96 and 144 hour post fertilization (hpf). LPO was increased with the advancement of morphogenesis; however, ethanol or the circulation status had no effect. We further analyzed alcohol dehydrogenase (Adh 5 and adh8) and aldehyde dehydrogenase (Aldh9A and Aldh1A2) enzyme mRNAs in the embryos exposed to 400 mM ethanol for 24h. A developmental stage specific reduction in these enzyme mRNAs by ethanol was observed. We conclude that ethanol-induced disruption in circulation during embryogenesis is a potential cause of the development of FASD features in medaka. PMID:18621148

  1. Induction Therapy for Thymoma.

    PubMed

    Ahmad, Usman; Huang, James

    2016-08-01

    Thymomas are uncommon tumors that can present as locally advanced tumors in approximately 30% of the patients. Stage and complete resection are the strongest prognostic factors. For locally advanced tumors, induction treatment may improve the ability to achieve a complete resection. Combination treatment with cisplatin, doxorubicin, and cyclophosphamide is the most commonly used induction regimen. Similar rates of resectability are noted with the use of induction chemotherapy and chemoradiation therapy; however, more tumor necrosis is noted with the addition of radiation. PMID:27427527

  2. Epstein-Barr virus nuclear protein EBNA3C directly induces expression of AID and somatic mutations in B cells.

    PubMed

    Kalchschmidt, Jens S; Bashford-Rogers, Rachael; Paschos, Kostas; Gillman, Adam C T; Styles, Christine T; Kellam, Paul; Allday, Martin J

    2016-05-30

    Activation-induced cytidine deaminase (AID), the enzyme responsible for induction of sequence variation in immunoglobulins (Igs) during the process of somatic hypermutation (SHM) and also Ig class switching, can have a potent mutator phenotype in the development of lymphoma. Using various Epstein-Barr virus (EBV) recombinants, we provide definitive evidence that the viral nuclear protein EBNA3C is essential in EBV-infected primary B cells for the induction of AID mRNA and protein. Using lymphoblastoid cell lines (LCLs) established with EBV recombinants conditional for EBNA3C function, this was confirmed, and it was shown that transactivation of the AID gene (AICDA) is associated with EBNA3C binding to highly conserved regulatory elements located proximal to and upstream of the AICDA transcription start site. EBNA3C binding initiated epigenetic changes to chromatin at specific sites across the AICDA locus. Deep sequencing of cDNA corresponding to the IgH V-D-J region from the conditional LCL was used to formally show that SHM is activated by functional EBNA3C and induction of AID. These data, showing the direct targeting and induction of functional AID by EBNA3C, suggest a novel role for EBV in the etiology of B cell cancers, including endemic Burkitt lymphoma. PMID:27217538

  3. Green Fluorescent Protein as a Visual Marker in Somatic Hybridization

    PubMed Central

    OLIVARES‐FUSTER, O.; PEÑA, L.; DURAN‐VILA, N.; NAVARRO, L.

    2002-01-01

    Using a transgenic citrus plant expressing Green Fluorescent Protein (GFP) as a parent in somatic fusion experiments, we investigated the suitability of GFP as an in vivo marker to follow the processes of protoplast fusion, regeneration and selection of hybrid plants. A high level of GFP expression was detected in transgenic citrus protoplasts, hybrid callus, embryos and plants. It is demonstrated that GFP can be used for the continuous monitoring of the fusion process, localization of hybrid colonies and callus, and selection of somatic hybrid embryos and plants. PMID:12096810

  4. 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

  5. Response to Nodal morphogen gradient is determined by the kinetics of target gene induction

    PubMed Central

    Dubrulle, Julien; Jordan, Benjamin M; Akhmetova, Laila; Farrell, Jeffrey A; Kim, Seok-Hyung; Solnica-Krezel, Lilianna; Schier, Alexander F

    2015-01-01

    Morphogen gradients expose cells to different signal concentrations and induce target genes with different ranges of expression. To determine how the Nodal morphogen gradient induces distinct gene expression patterns during zebrafish embryogenesis, we measured the activation dynamics of the signal transducer Smad2 and the expression kinetics of long- and short-range target genes. We found that threshold models based on ligand concentration are insufficient to predict the response of target genes. Instead, morphogen interpretation is shaped by the kinetics of target gene induction: the higher the rate of transcription and the earlier the onset of induction, the greater the spatial range of expression. Thus, the timing and magnitude of target gene expression can be used to modulate the range of expression and diversify the response to morphogen gradients. DOI: http://dx.doi.org/10.7554/eLife.05042.001 PMID:25869585

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

    PubMed Central

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

    2015-01-01

    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

  7. Induction: Making the Leap

    ERIC Educational Resources Information Center

    Ling, Lorraine M.

    2009-01-01

    This article provides a critical examination of a variety of approaches to induction focusing especially upon Australia and other Pacific Rim countries. The question of the purposes induction serves for graduate teachers, experienced teachers and education systems is addressed in terms of whether it is a technical exercise which preserves the…

  8. 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

  9. Somatization and fashionable diagnoses: illness as a way of life.

    PubMed

    Ford, C V

    1997-01-01

    The history of "nondisease" dates back, at least 4000 years, to early descriptions of hysteria. More recently somatization became a part of the official diagnostic nomenclature by creation of the DSM III category, "somatoform disorders." Somatization can serve as a rationalization for psychosocial problems or as a coping mechanism, and for some illness, becomes a way of life. One variation of somatization can be the "fashionable diagnosis", for example, fibromyalgia, multiple chemical sensitivities, dysautonomia, and, in the past, "reactive hypoglycemia". These disorders are phenomenologically related to environmental or occupational syndromes and mass psychogenic illness. Fashionable illnesses are characterized by (i) vague, subjective multisystem complaints, (ii) a lack of objective laboratory findings, (iii) quasi-scientific explanations, (iv) overlap from one fashionable diagnosis to another, (v) symptoms consistent with depression or anxiety or both, (vi) denial of psychosocial distress or attribution of it to the illness. Fashionable diagnoses represent a heterogeneous collection of physical diseases, somatization, and anxiety or depression. They are final common symptomatic pathways for a variety of influences including environmental factors, intrapersonal distress and solutions to social problems. A fashionable diagnosis allows psychosocial distress to be comfortably hidden from both the patient and the physician, but premature labeling can also mask significant physical disease. Hysteria remains alive and well and one contemporary hiding place is fashionable illness. PMID:9456062

  10. 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

  11. 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,…

  12. Predictors of Somatic Symptoms in Younger Rural Adolescents

    ERIC Educational Resources Information Center

    Christiansen, Lois M.; Copeland, Ellis P.; Stapert, Erika B.

    2008-01-01

    This study investigated the presence and strength of the relationship between daily hassles, coping style, negative mood regulations, and somatic symptomatology in junior high rural adolescents. Five paper-and-pencil instruments assessing perceived daily hassles, coping strategies, ability to successfully alleviate a negative mood state, degree of…

  13. Embodied Cognition: Somatic Markers, Purposes and Emotional Orientations

    ERIC Educational Resources Information Center

    Brown, Laurinda; Reid, David A.

    2006-01-01

    We describe the "somatic marker hypothesis" proposed by Damasio (1996) to account for the ability of most people to make decisions quickly and continually in the course of their lives. We relate this hypothesis to two other theoretical constructs, emotional orientations and purposes, which we have used in our research on students' reasoning and…

  14. 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)

  15. Integrated analysis of germline and somatic variants in ovarian cancer.

    PubMed

    Kanchi, Krishna L; Johnson, Kimberly J; Lu, Charles; McLellan, Michael D; Leiserson, Mark D M; Wendl, Michael C; Zhang, Qunyuan; Koboldt, Daniel C; Xie, Mingchao; Kandoth, Cyriac; McMichael, Joshua F; Wyczalkowski, Matthew A; Larson, David E; Schmidt, Heather K; Miller, Christopher A; Fulton, Robert S; Spellman, Paul T; Mardis, Elaine R; Druley, Todd E; Graubert, Timothy A; Goodfellow, Paul J; Raphael, Benjamin J; Wilson, Richard K; Ding, Li

    2014-01-01

    We report the first large-scale exome-wide analysis of the combined germline-somatic landscape in ovarian cancer. Here we analyse germline and somatic alterations in 429 ovarian carcinoma cases and 557 controls. We identify 3,635 high confidence, rare truncation and 22,953 missense variants with predicted functional impact. We find germline truncation variants and large deletions across Fanconi pathway genes in 20% of cases. Enrichment of rare truncations is shown in BRCA1, BRCA2 and PALB2. In addition, we observe germline truncation variants in genes not previously associated with ovarian cancer susceptibility (NF1, MAP3K4, CDKN2B and MLL3). Evidence for loss of heterozygosity was found in 100 and 76% of cases with germline BRCA1 and BRCA2 truncations, respectively. Germline-somatic interaction analysis combined with extensive bioinformatics annotation identifies 222 candidate functional germline truncation and missense variants, including two pathogenic BRCA1 and 1 TP53 deleterious variants. Finally, integrated analyses of germline and somatic variants identify significantly altered pathways, including the Fanconi, MAPK and MLL pathways. PMID:24448499

  16. Integrated Analysis of Germline and Somatic Variants in Ovarian Cancer

    PubMed Central

    Kanchi, Krishna L.; Johnson, Kimberly J.; Lu, Charles; McLellan, Michael D.; Leiserson, Mark D.M.; Wendl, Michael C.; Zhang, Qunyuan; Koboldt, Daniel C.; Xie, Mingchao; Kandoth, Cyriac; McMichael, Joshua F.; Wyczalkowski, Matthew A.; Larson, David E.; Schmidt, Heather K.; Miller, Christopher A.; Fulton, Robert S.; Spellman, Paul T.; Mardis, Elaine R.; Druley, Todd E.; Graubert, Timothy A.; Goodfellow, Paul J.; Raphael, Benjamin J.; Wilson, Richard K.; Ding, Li

    2014-01-01

    We report the first large-scale exome-wide analysis of the combined germline-somatic landscape in ovarian cancer. Here we analyze germline and somatic alterations in 429 ovarian carcinoma cases and 557 controls. We identify 3,635 high confidence, rare truncation and 22,953 missense variants with predicted functional impact. We find germline truncation variants and large deletions across Fanconi pathway genes in 20% of cases. Enrichment of rare truncations is shown in BRCA1, BRCA2, and PALB2. Additionally, we observe germline truncation variants in genes not previously associated with ovarian cancer susceptibility (NF1, MAP3K4, CDKN2B, and MLL3). Evidence for loss of heterozygosity was found in 100% and 76% of cases with germline BRCA1 and BRCA2 truncations respectively. Germline-somatic interaction analysis combined with extensive bioinformatics annotation identifies 237 candidate functional germline truncation and missense variants, including 2 pathogenic BRCA1 and 1 TP53 deleterious variants. Finally, integrated analyses of germline and somatic variants identify significantly altered pathways, including the Fanconi, MAPK, and MLL pathways. PMID:24448499

  17. Somatic alterations in lung cancer: Do environmental factors matter?

    PubMed

    Gibelin, Cécilia; Couraud, Sébastien

    2016-10-01

    Lung cancer is the leading cause of cancer-related death worldwide and smoking tobacco is now definitively established as the dominant risk factor for the malignancy. However, lung cancer can and does occur in never smokers, thus illustrating the existence of other risk factors. Many of these latter are environmental, such as workplace and home carcinogens, air pollution, radon and certain infectious agents. One of the most remarkable advances in thoracic oncology is the recent identification of somatic oncogenic molecular abnormalities, some of which are candidates for targeted therapies. Active smoking is now known to cause a particular somatic profile distinct from that found in never-smokers. This has logically led researchers to consider the possibility that exposure to other lung cancer risk factors may also engender a unique somatic profile. Thus, with the present work, we sought to review current knowledge on somatic profiles in the setting of bronchial cancer (for targetable mutations such as EGFR, ALK, BRAF and HER2, as well as some non-targetable mutations such as TP53, and KRAS) and their associations with environmental risk factors for the malignancy. PMID:27597280

  18. 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

    2015-12-10

    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

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

    PubMed Central

    Cheloufi, Sihem; Elling, Ulrich; Hopfgartner, Barbara; Jung, Youngsook L; Murn, Jernej; Ninova, Maria; Hubmann, Maria; Badeaux, Aimee I; Ang, Cheen Euong; 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; Penninger, Josef M; Zuber, Johannes; Hochedlinger, Konrad

    2016-01-01

    Cellular differentiation involves profound remodeling 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 RNAi screens targeting chromatin factors during transcription factor-mediated reprogramming of mouse fibroblasts to induced pluripotent stem cells (iPSCs). Remarkably, subunits of the chromatin assembly factor-1 (CAF-1) complex 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 iPSC 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 as 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

  20. Photodynamic inactivation of somatic frog nerve ex vivo

    NASA Astrophysics Data System (ADS)

    Akchurin, Garif G.; Seliverstov, George A.; Akchurin, George G.; Kudryashova, Svetlana Y.

    2004-06-01

    New techniques research mechanisms of photdynamic reactions at somatic frog nerve was approved. Dosimetry PDT with minimum time resolution ~1ms determined by changing the amplitude of compound action potential of somatic frog nerve. Light-induced inactivation of dynamic response of somatic frog nerve on electrical pulsed excitation was study ex vivo. The light-sensitive dyes: methylene blue (Mb), Indocianin green and eryhtrocin-B has been used on photodynamic induced inactivation of the processes generation nerve pulses. Inactivation of consequence action potential of somatic frog nerve using excitation of electical pulsed was achieved by irradiation with He-Ne laser light in a red spectral region (λ=633 nm, power level 2-20 mW), diode laser (λ=805 nm, P<0.1-1 W/cm2) in the case of Indocianin green and YAG:Nd laser (λ=532 nm, P~1mW) for eryhtrocin-B. It was discovered that methylene blue, Indocainine green and erytrocin-B decrease of the amplitude compound action potential of the ensemble neurons. The possible cell death mechanism was connected with damage of the sodium potassium adenosine triphosphatase (K-Na ATP) active transport which decrease of amplitude of compound action potential and decrease lifetime ionic channel of membrane nerve.

  1. 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…

  2. 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)

  3. 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...

  4. Principles of Induction Accelerators

    NASA Astrophysics Data System (ADS)

    Briggs*, Richard J.

    The basic concepts involved in induction accelerators are introduced in this chapter. The objective is to provide a foundation for the more detailed coverage of key technology elements and specific applications in the following chapters. A wide variety of induction accelerators are discussed in the following chapters, from the high current linear electron accelerator configurations that have been the main focus of the original developments, to circular configurations like the ion synchrotrons that are the subject of more recent research. The main focus in the present chapter is on the induction module containing the magnetic core that plays the role of a transformer in coupling the pulsed power from the modulator to the charged particle beam. This is the essential common element in all these induction accelerators, and an understanding of the basic processes involved in its operation is the main objective of this chapter. (See [1] for a useful and complementary presentation of the basic principles in induction linacs.)

  5. Progress in Induction Linacs

    SciTech Connect

    Caporaso, G J

    2000-09-27

    This presentation will be a broad survey of progress in induction technology over the past four years. Much work has been done on accelerators for hydrodynamic test radiography and other applications. Solid-state pulsers have been developed which can provide unprecedented flexibility and precision in pulse format and accelerating voltage for both ion and electron induction machines. Induction linacs can now be built which can operate with MHz repetition rates. Solid-state technology has also made possible the development of fast kickers for precision control of high current beams. New insulator technology has been developed which will improve conventional induction linacs in addition to enabling a new class of high gradient induction linacs.

  6. 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

    for induction of somatic cell mutations in Drosophila larvae exposed to CS. PMID:26138228

  7. 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%, Ψ 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%; Ψ 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

  8. Somatic cell counts of milk from Dairy Herd Improvement herds during 2010

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Test-day data from all herds enrolled in Dairy Herd Improvement (DHI) somatic cell testing during 2010 were examined to assess the status of national milk quality. Somatic cell score (SCS) is reported to AIPL and was converted to somatic cell count (SCC) for calculating herd and State averages. The ...

  9. Somatization and Malingering for Workers' Compensation Applicants: A Cross-Cultural MMPI Study.

    ERIC Educational Resources Information Center

    DuAlba, Les; Scott, Ronald L.

    1993-01-01

    Conducted post hoc analysis of 60 Hispanics and 60 Caucasians who had filed under workers' compensation to examine cross-cultural differences of somatization and malingering as assessed by Minnesota Multiphasic Personality Inventory. Significant differences were found for somatization; Hispanics were more likely to somatize. Minimal differences…

  10. Parkinson disease (PARK) genes are somatically mutated in cutaneous melanoma

    PubMed Central

    Samuels, Yardena; Azizi, Esther; Qutob, Nouar; Inzelberg, Lilah; Domany, Eytan; Schechtman, Edna; Friedman, Eitan

    2016-01-01

    Objective: To assess whether Parkinson disease (PD) genes are somatically mutated in cutaneous melanoma (CM) tissue, because CM occurs in patients with PD at higher rates than in the general population and PD is more common than expected in CM cohorts. Methods: We cross-referenced somatic mutations in metastatic CM detected by whole-exome sequencing with the 15 known PD (PARK) genes. We computed the empirical distribution of the sum of mutations in each gene (Smut) and of the number of tissue samples in which a given gene was mutated at least once (SSampl) for each of the analyzable genes, determined the 90th and 95th percentiles of the empirical distributions of these sums, and verified the location of PARK genes in these distributions. Identical analyses were applied to adenocarcinoma of lung (ADENOCA-LUNG) and squamous cell carcinoma of lung (SQUAMCA-LUNG). We also analyzed the distribution of the number of mutated PARK genes in CM samples vs the 2 lung cancers. Results: Somatic CM mutation analysis (n = 246) detected 315,914 mutations in 18,758 genes. Somatic CM mutations were found in 14 of 15 PARK genes. Forty-eight percent of CM samples carried ≥1 PARK mutation and 25% carried multiple PARK mutations. PARK8 mutations occurred above the 95th percentile of the empirical distribution for SMut and SSampl. Significantly more CM samples harbored multiple PARK gene mutations compared with SQUAMCA-LUNG (p = 0.0026) and with ADENOCA-LUNG (p < 0.0001). Conclusions: The overrepresentation of somatic PARK mutations in CM suggests shared dysregulated pathways for CM and PD. PMID:27123489

  11. 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

  12. Abscisic Acid-Dependent and -Independent Expression of the Carrot Late-Embryogenesis-Abundant-Class Gene Dc3 in Transgenic Tobacco Seedlings1

    PubMed Central

    Siddiqui, Najeeb U.; Chung, Hwa-Jee; Thomas, Terry L.; Drew, Malcolm C.

    1998-01-01

    We studied the expression of three promoter 5′ deletion constructs (−218, −599, and −1312) of the LEA (late embryogenesis abundant)-class gene Dc3 fused to β-glucuronidase (GUS), where each construct value refers to the number of base pairs upstream of the transcription start site at which the deletion occurred. The Dc3 gene is noted for its induction by abscisic acid (ABA), but its response to other plant hormones and various environmental stresses has not been reported previously for vegetative cells. Fourteen-day-old transgenic tobacco (Nicotiana tabacum L.) seedlings were exposed to dehydration, hypoxia, salinity, exogenous ethylene, or exogenous methyl jasmonate (MeJa). GUS activity was quantified fluorimetrically and expression was observed by histochemical staining of the seedlings. An increase in GUS activity was observed in plants with constructs −599 and −1312 in response to dehydration and s