71 research outputs found

    Site-Specific Insertion Polymorphism of the MITE Alex-1 in the Genus Coffea Suggests Interspecific Gene Flow

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    Miniature Inverted-repeat Transposable Elements (MITEs) are small nonautonomous class-II transposable elements distributed throughout eukaryotic genomes. We identified a novel family of MITEs (named Alex) in the Coffea canephora genome often associated with expressed sequences. The Alex-1 element is inserted in an intron of a gene at the CcEIN4 locus. Its mobility was demonstrated by sequencing the insertion site in C. canephora accessions and Coffea species. Analysis of the insertion polymorphism of Alex-1 at this locus in Coffea species and in C. canephora showed that there was no relationship between the geographical distribution of the species, their phylogenetic relationships, and insertion polymorphism. The intraspecific distribution of C. canephora revealed an original situation within the E diversity group. These results suggest possibly greater gene flow between species than previously thought. This MITE family will enable the study of the C. canephora genome evolution, phylogenetic relationships, and possible gene flows within the Coffea genus

    Microcollinearity in an ethylene receptor coding gene region of the Coffea canephora genome is extensively conserved with Vitis vinifera and other distant dicotyledonous sequenced genomes

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    Background: Coffea canephora, also called Robusta, belongs to the Rubiaceae, the fourth largest angiosperm family. This diploid species (2x = 2n = 22) has a fairly small genome size of approximate to 690 Mb and despite its extreme economic importance, particularly for developing countries, knowledge on the genome composition, structure and evolution remain very limited. Here, we report the 160 kb of the first C. canephora Bacterial Artificial Chromosome (BAC) clone ever sequenced and its fine analysis. Results: This clone contains the CcEIN4 gene, encoding an ethylene receptor, and twenty other predicted genes showing a high gene density of one gene per 7.8 kb. Most of them display perfect matches with C. canephora expressed sequence tags or show transcriptional activities through PCR amplifications on cDNA libraries. Twenty-three transposable elements, mainly Class II transposon derivatives, were identified at this locus. Most of these Class II elements are Miniature Inverted-repeat Transposable Elements (MITE) known to be closely associated with plant genes. This BAC composition gives a pattern similar to those found in gene rich regions of Solanum lycopersicum and Medicago truncatula genomes indicating that the CcEIN4 regions may belong to a gene rich region in the C. canephora genome. Comparative sequence analysis indicated an extensive conservation between C. canephora and most of the reference dicotyledonous genomes studied in this work, such as tomato (S. lycopersicum), grapevine (V. vinifera), barrel medic M. truncatula, black cottonwood (Populus trichocarpa) and Arabidopsis thaliana. The higher degree of microcollinearity was found between C. canephora and V. vinifera, which belong respectively to the Asterids and Rosids, two clades that diverged more than 114 million years ago. Conclusion: This study provides a first glimpse of C. canephora genome composition and evolution. Our data revealed a remarkable conservation of the microcollinearity between C. canephora and V. vinifera and a high conservation with other distant dicotyledonous reference genomes. Altogether, these results provide valuable information to identify candidate genes in C. canephora genome and serve as a foundation to establish strategies for whole genome sequencing. Future large-scale sequence comparison between C. canephora and reference sequenced genomes will help in understanding the evolutionary history of dicotyledonous plants

    Resistance to paclitaxel in a cisplatin-resistant ovarian cancer cell line is mediated by P-glycoprotein

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    The IGROVCDDP cisplatin-resistant ovarian cancer cell line is also resistant to paclitaxel and models the resistance phenotype of relapsed ovarian cancer patients after first-line platinum/taxane chemotherapy. A TaqMan low-density array (TLDA) was used to characterise the expression of 380 genes associated with chemotherapy resistance in IGROVCDDP cells. Paclitaxel resistance in IGROVCDDP is mediated by gene and protein overexpression of P-glycoprotein and the protein is functionally active. Cisplatin resistance was not reversed by elacridar, confirming that cisplatin is not a P-glycoprotein substrate. Cisplatin resistance in IGROVCDDP is multifactorial and is mediated in part by the glutathione pathway and decreased accumulation of drug. Total cellular glutathione was not increased. However, the enzyme activity of GSR and GGT1 were up-regulated. The cellular localisation of copper transporter CTR1 changed from membrane associated in IGROV-1 to cytoplasmic in IGROVCDDP. This may mediate the previously reported accumulation defect. There was decreased expression of the sodium potassium pump (ATP1A), MRP1 and FBP which all have been previously associated with platinum accumulation defects in platinum-resistant cell lines. Cellular localisation of MRP1 was also altered in IGROVCDDP shifting basolaterally, compared to IGROV-1. BRCA1 was also up-regulated at the gene and protein level. The overexpression of P-glycoprotein in a resistant model developed with cisplatin is unusual. This demonstrates that P-glycoprotein can be up-regulated as a generalised stress response rather than as a specific response to a substrate. Mechanisms characterised in IGROVCDDP cells may be applicable to relapsed ovarian cancer patients treated with frontline platinum/taxane chemotherapy

    The Influence of Manga on the Graphic Novel

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    This material has been published in The Cambridge History of the Graphic Novel edited by Jan Baetens, Hugo Frey, Stephen E. Tabachnick. This version is free to view and download for personal use only. Not for re-distribution, re-sale or use in derivative works. © Cambridge University PressProviding a range of cogent examples, this chapter describes the influences of the Manga genre of comics strip on the Graphic Novel genre, over the last 35 years, considering the functions of domestication, foreignisation and transmedia on readers, markets and forms

    Broyage et abrasion au néolithique ancien (caractérisation technique et fonctionnelle de l'outillage en grÚs du bassin parisien)

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    L'avÚnement du Néolithique ancien se traduit par un renouveau des activités de broyage, mouture et abrasion sur les sites d 'habitat du Bassin parisien. La caractérisation des modes d'exploitation des grÚs est appréhendée à travers une analyse pétrographique. Les modes de fabrication et de gestion démontrent de véritables cycles d'entretien et de réutilisation des supports. L'analyse des caractÚres morphologiques et métriques souligne l'existence de modules " standards " de meules et molettes. Une méthode originale de reconnaissance des traces d'utilisation permet de formuler de nouvelles hypothÚses quant à leur fonction. Une évolution de la maßtrise des procédés de transformation des céréales est perceptible entre le Rubané et le Villeneuve-Saint-Germain. L'augmentation de la part des activités de mouture se fait en parallÚle de celle de la consommation de la faune domestique. La distribution du mobilier en grÚs dans l'espace villageois reflÚte une partition des activités. L'étude de l'outillage en grÚs contribue ainsi à notre connaissance des modes de subsistance et du fonctionnement socio-économique des premiÚres sociétés néolithiques dans la moitié Nord de la France.PARIS1-BU Pierre MendÚs-France (751132102) / SudocSudocFranceF

    Properties of Photosystem II lacking the PsbJ subunit

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    International audienceAbstract Photosystem II (PSII), the oxygen-evolving enzyme, consists of 17 trans-membrane and 3 extrinsic membrane proteins. Other subunits bind to PSII during assembly, like Psb27, Psb28, Tsl0063. The presence of Psb27 has been proposed (Zabret et al. 2021; Huang et al. 2021; Xiao et al. 2021) to prevent the binding of PsbJ, a single transmembrane α-helix close to the quinone Q B binding site. Consequently, a PSII rid of Psb27, Psb28 and Tsl0034 prior to the binding of PsbJ would logically correspond to an assembly intermediate. The present work describes experiments aiming at further characterizing such a ΔPsbJ-PSII, purified from the thermophilic Thermosynechococcus elongatus , by means of MALDI-TOF spectroscopy, Thermoluminescence, EPR spectroscopy and UV-visible time-resolved spectroscopy. In the purified ΔPsbJ-PSII, an active Mn 4 CaO 5 cluster is present in 60-70 % of the centers. In these centers, although the forward electron transfer seems not affected, the Em of the Q B /Q B - couple increases by ≄ 120 mV thus disfavoring the electron coming back on Q A . The increase of the energy gap between Q A /Q A - and Q B /Q B - could contribute in a protection against the charge recombination between the donor side and Q B - , identified at the origin of photoinhibition under low light (Keren et al. 1997), and possibly during the slow photoactivation process

    Poisoning exposure from non-pharmaceutical products in residents of structured living facilities

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    International audienceObjective The objectives of this study were to describe poisonings occurring in older or disabled patients residing in structured living facilities, identify risk factors, and propose preventive measures. Method This was a prospective and observational study, covering all cases of poisoning occurring in structured living facilities in the Brittany region of France. All calls were received at the Grand Ouest Poison Control Centre (PCC) of Angers and were recorded from 1 February 2019 to 31 January 2020. The clinical severity of the poisonings was assessed using the Poisoning Severity Score (PSS). Clinical severity was compared by univariate and multivariate analyses using the following dependent variables: PSS score < 2 and PSS >= 2. Results This study included 158 residents with a median age of 83 years (5-116 years old). The average number of residents supervised by a member of the supervisory staff was 11 (+/-10.7). The substance ingested was a personal hygiene product or a cleaning product in 48% and 25% of cases, respectively. The most frequently ingested product was a bar of soap (n = 20). All moderate to severe cases (4.6%, n = 8 including one death) occurred in residents with dementia living in nursing homes for elderly patients, and 9% of residents required hospital treatment. In more than 50% of cases (n = 83), the product was provided by the facility and in 23% (n = 40), it was brought in by the family. Ingestion of a bar of soap or a product brought in by the family was significantly associated with higher poisoning severity (PSS >= 2). After adjustment for age, sex and the number of residents per supervisor, the severity of poisoning was significantly greater after ingestion of a bar of soap (OR = 12.33, CI95 [2.12, 71.63], p = 0.005). Conclusion Older adults residing in medical facilities who have a history of dementia and/or cognitive impairment are more at risk of non-medicinal product poisoning. Clinical severity and the hospitalisation rate were greater when bar soap was ingested
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