80 research outputs found

    Location of chlorogenic acid biosynthesis pathway and polyphenol oxidase genes in a new interspecific anchored linkage map of eggplant

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    © Gramazio et al.; licensee BioMed Central. 2014. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated

    Characterising the CI and CI-like carbonaceous chondrites using thermogravimetric analysis and infrared spectroscopy

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    The CI and CI-like chondrites provide a record of aqueous alteration in the early solar system. However, the CI-like chondrites differ in having also experienced a late stage period of thermal metamorphism. In order to constrain the nature and extent of the aqueous and thermal alteration, we have investigated the bulk mineralogy and abundance of H2O in the CI and CI-like chondrites using thermogravimetric analysis and infrared spectroscopy. The CI chondrites Ivuna and Orgueil show significant mass loss (28.5–31.8 wt.%) upon heating to 1000 °C due to dehydration and dehydroxylation of abundant phyllosilicates and Fe-(oxy)hydroxides and the decomposition of Fe-sulphides, carbonates and organics. Infrared spectra for Ivuna and Orgueil have a prominent 3-μm feature due to bound −OH/H2O in phyllosilicates and Fe-(oxy)hydroxides and only a minor 11-μm feature from anhydrous silicates. These characteristics are consistent with previous studies indicating that the CI chondrites underwent near-complete aqueous alteration. Similarities in the total abundance of H2O and 3 μm/11 μm ratio suggest that there is no difference in the relative degree of hydration experienced by Ivuna and Orgueil. In contrast, the CI-like chondrites Y-82162 and Y-980115 show lower mass loss (13.8–18.8 wt.%) and contain >50 % less H2O than the CI chondrites. The 3-μm feature is almost absent from spectra of Y-82162 and Y-980115 but the 11-μm feature is intense. The CI-like chondrites experienced thermal metamorphism at temperatures >500 °C that initially caused dehydration and dehydroxylation of phyllosilicates before partial recrystallization back into anhydrous silicates. The surfaces of many C-type asteroids were probably heated through impact metamorphism and/or solar radiation, so thermally altered carbonaceous chondrites are likely good analogues for samples that will be returned by the Hayabusa-2 and OSIRIS-REx missions

    Comparison of transcriptome-derived simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers for genetic fingerprinting, diversity evaluation, and establishment of relationships in eggplants

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    [EN] Simple sequence repeat (SSR) and single nucleotide polymorphism (SNP) markers are amongst the most common markers of choice for studies of diversity and relationships in horticultural species. We have used 11 SSR and 35 SNP markers derived from transcriptome sequencing projects to fingerprint 48 accessions of a collection of brinjal (Solanum melongena), gboma (S. macrocarpon) and scarlet (S. aethiopicum) eggplant complexes, which also include their respective wild relatives S. incanum, S. dasyphyllum and S. anguivi. All SSR and SNP markers were polymorphic and 34 and 36 different genetic fingerprints were obtained with SSRs and SNPs, respectively. When combining both markers all accessions but two had different genetic profiles. Although on average SSRs were more informative than SNPs, with a higher number of alleles, genotypes and polymorphic information content (PIC), and expected heterozygosity (He) values, SNPs have proved highly informative in our materials. Low observed heterozygosity (Ho) and high fixation index (f) values confirm the high degree of homozygosity of eggplants. Genetic identities within groups of each complex were higher than with groups of other complexes, although differences in the ranks of genetic identity values among groups were observed between SSR and SNP markers. For low and intermediate values of pair-wise SNP genetic distances, a moderate correlation between SSR and SNP genetic distances was observed (r(2) = 0.592), but for high SNP genetic distances the correlation was low (r(2) = 0.080). The differences among markers resulted in different phenogram topologies, with a different eggplant complex being basal (gboma eggplant for SSRs and brinjal eggplant for SNPs) to the two others. Overall the results reveal that both types of markers are complementary for eggplant fingerprinting and that interpretation of relationships among groups may be greatly affected by the type of marker used.This work has been funded by European Union's Horizon 2020 Research and Innovation Programme under Grant Agreement No 677379 (G2P-SOL project: Linking genetic resources, genomes and phenotypes of Solanaceous crops) and by Spanish Ministerio de Economia y Competitividad and Fondo Europeo de Desarrollo Regional (Grant AGL2015-64755-R from MINECO/FEDER). Pietro Gramazio is grateful to Universitat Politecnica de Valencia for a pre-doctoral contract (Programa FPI de la UPV-Subprograma 1/2013 call). Mariola Plazas is grateful to Spanish Ministerio de Economia, Industria y Competitividad for a post-doctoral grant within the Juan de la Cierva-Formacion programme (FJCI-2015-24835).Gramazio, P.; Prohens Tomás, J.; Borras, D.; Plazas Ávila, MDLO.; Herraiz García, FJ.; Vilanova Navarro, S. 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    Presolar SiC abundances in primitive meteorites by NanoSIMS raster ion imaging of insoluble organic matter

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    Here we present results obtained with NanoSIMS raster ion imaging to determine the abundance of presolar SiC in the insoluble organic matter (IOM) extracted from a number of different classes of chondrites (both carbonaceous and ordinary). This builds on previous work [1] aimed at obtaining SiC abundances in primitive meteorites by SIMS and comparing them with noble gas analyses. Both IOM and presolar grains are found in similar CI-like relative abundances in the matrices of the most primitive chondrites [2, 3], indicating that a homogeneous mixture of grains was incorporated in the various parent bodies [3]. Both are then subjected to thermal and hydrothermal processing after parent body formation [4]. However, there are significant variations in the matrix-normalized abundances of SiC grains estimated from noble gases carried by presolar grains, which suggest that the primitive chondrites did not form from a well-mixed reservoir of presolar grains. Variations in the source material were attributed to the destruction of presolar grains by heating in the solar nebula (temperatures that may have exceeded 700°C) and were linked to the volatile element fractionations in chondrites [5]. The CR chondrites have amongst the lowest matrix-normalized SiC abundances, and largest volatile element ractionations, reported in the carbonaceous chondrites [5]. However, they contain the most primitive IOM of any chondrite class [6-7], which has experienced peak temperatures of <300°C [8]. These lowtemperatures could not have affected the SiC grains or their noble gas concentrations, indicating that either the IOM escaped heating (implying that it is not presolar)or SiC was degassed/destroyed at low temperatures, perhaps during parent body processing [3]. Thus, in order to resolve this contradiction, it is necessary to determine SiC abundances independently of noble gases. Ion imaging of SiC grains is a direct technique that has been shown to successfully identify presolar SiC grains amongst others

    The potential for crop to wild hybridization in eggplant (Solanum melongena ; solanaceae) in southern India

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    Premise of the study: In India and elsewhere, transgenic Bt eggplant (Solanum melongena) has been developed to reduce insect herbivore damage, but published studies of the potential for pollen-mediated, crop-to-wild gene flow are scant. This information is useful for risk assessments as well as in situ conservation strategies for wild germplasm. Methods: In 2010-2014, we surveyed 23 populations of wild/weedy eggplant (Solanum insanum; known as wild brinjal), carried out hand-pollination experiments, and observed pollinators to assess the potential for crop-to-wild gene flow in southern India. Key results: Wild brinjal is a spiny, low-growing perennial commonly found in disturbed sites such as roadsides, wastelands, and sparsely vegetated areas near villages and agricultural fields. Fourteen of the 23 wild populations in our study occurred within 0.5 km of cultivated brinjal and at least nine flowered in synchrony with the crop. Hand crosses between wild and cultivated brinjal resulted in seed set and viable F-1 progeny. Wild brinjal flowers that were bagged to exclude pollinators did not set fruit, and fruit set from manual self-pollination was low. The exserted stigmas of wild brinjal are likely to promote outcrossing. The most effective pollinators appeared to be bees (Amegilla, Xylocopa, Nomia, and Heterotrigona spp.), which also were observed foraging for pollen on crop brinjal. Conclusion: Our findings suggest that hybridization is possible between cultivated and wild brinjal in southern India. Thus, as part of the risk assessment process, we assume that transgenes from the crop could spread to wild brinjal populations that occur nearby

    Placentas from pregnancies conceived by IVF/ICSI have a reduced DNA methylation level at the H19 and MEST differentially methylated regions

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    Does IVF/ICSI have an effect on the epigenetic regulation of the human placenta? We found a reduced DNA methylation level at the H19 and MEST differentially methylated regions (DMRs), and an increased RNA expression of H19 in placentas from pregnancies conceived by IVF/ICSI when compared with placentas from spontaneous conception. Changes in fetal environment are associated with adverse health outcomes. The placenta is pivotal for intrauterine environment. Animal studies show that epigenetic regulation plays an important role in these environment-induced phenotypic effects. Also, the preimplantation embryo environment affects birthweight as well as the risk of chronic adult diseases. Epigenetic processes are sensitive to the environment, especially during the period around conception. Placental tissue was collected from 35 spontaneously conceived pregnancies and 35 IVF/ICSI (5 IVF, 30 ICSI) derived pregnancies. We quantitatively analysed the DNA methylation patterns of a number of consecutive CpGs in the core regions of DMRs and other regulatory regions of imprinted genes, since these are involved in placental and fetal growth and development. By using pyrosequencing, the DNA methylation at seven germline-derived primary DMRs was analysed quantitatively. Five of these are maternally methylated (MEST isoform and , PEG3, KCNQ1OT1 and SNRPN) and two are paternally methylated [H19 DMR and the intergenic region between DLK1 and MEG3 (IG-DMR)]. The post-fertilization-derived secondary DMRs, IGF2 (DMR0 and 2) and IG-DMR (CG7, also called MEG3 DMR), and the MEG3 promoter region were examined as well. In case of differential methylation between the two groups, the effect on gene expression was assessed by quantitative real-time PCR. Both the promoter region of MEST isoform and and the 6th CTCF binding site within the H19 DMR were significantly hypomethylated in the IVF/ICSI group. The phenomenon was consistently observed over all CpG sites analysed and not restricted to single CpG sites. The other primary and secondary DMRs were not affected. Expression of H19 was increased in the IVF/ICSI group, while that of IGF2 and MEST remained similar. In the IVF/ICSI group, mostly ICSI pregnancies were investigated. The ICSI technique or male subfertility could be a confounding factor. Therefore, our results are less generalizable to IVF pregnancies. The clinical effects of the observed placental hypomethylations on the developmental programming of the IVF/ICSI progeny, if any, are as yet unknown. Whether the hypomethylation is an adaptation of the placenta to maintain fetal supply and ameliorate the effects of environmental cues, or whether it is a deregulation leading to deranged developmental programming with or without increased vulnerability for disease, consistent with the developmental origins of health and disease hypothesis, needs further investigation. Partly funded by an unrestricted research grant by Organon BV (now MSD BV) without any role in study design, data collection and analysis, or preparation of the manuscript. No conflict of interests to declare. Dutch Trial Registry (NTR) number 1298
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