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991.
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993.
Tahina Rambolarimanana Lolona Ramamonjisoa Daniel Verhaegen Jean-Michel Leong Pock Tsy Laval Jacquin Tuong-Vi Cao-Hamadou Garel Makouanzi Jean-Marc Bouvet 《Tree Genetics & Genomes》2018,14(5):71
In forest tree genetic improvement, multi-trait genomic selection (GS) may have advantages in improving the accuracy of the genotype estimation and shortening selection cycles. For the breeding of Eucalyptus robusta, one of the most exotic planted species in Madagascar, volume at 49 months (V49), total lignin (TL), and holo-cellulose (Holo) were considered. For GS, 2919 single nucleotide polymorphisms (SNP) were used with the genomic best linear unbiased predictor (GBLUP) method, which was as efficient as the reproducing kernel Hilbert space (RKHS) and elastic net methods (EN), but more adapted to multi-trait modeling. The efficiency of individual I model, including the genomic data, was much higher than the provenance effect P model. For example, with V49, mean goodness-of-fit was: rI_Full =?0.79, rP_Full =?0.37 for I and P, respectively. The prediction accuracies using the cross-validation procedure were lower for V49: rI =?0.29 rP =?0.28. The genetic gains resulting from the indexes associating (V49, TL) and (V49, Holo) were higher using I than for the P model; for V49, the relative genetic gain was 37 and 20%, respectively, with 5% of selection intensity. The single-trait approach was as efficient as the multi-trait approach given the weak correlations between V49 and TL or Holo. The I model also brings greater diversity: for V49 the number of provenances represented in a selected population was two and three with the P model, and 6 and 16 with the I model. 相似文献
994.
Jean-Marc Lo-Guidice Hermann Herz Genevieve Lamblin Yves Plancke Philippe Roussel Michel Lhermitte 《Glycoconjugate journal》1997,14(1):113-125
Mucin glycopeptides were prepared from the respiratory mucus of a non-secretor, chronic bronchitic patient with blood group O, Lea+b-. Oligosaccharides were released by alkaline borohydride treatment and purified by anion-exchange chromatography, size-exclusion chromatography and high performance anion-exchange chromatography. Structural studies employed 400-MHz 1H-NMR spectroscopy and matrix assisted laser desorption/ionization mass spectrometry (MALDI-MS). Nine monosulfated oligosaccharides ranging in size from tetra- to hexasaccharide, were fully characterized in this study. The sulfate group occurs either on the C-3 of a terminal galactose residue or on the C-6 of a N-acetylglucosamine residue. In keeping with the non-secretor status of the patient, no structure with an (1-2)-linked fucose residue was found. Five of the structures had fucose present in (1-3)-linkage in the X determinant, while only one oligosaccharide (compound 7b) was seen with fucose (1-4)-linked in the Lea determinant. Eight structures isolated from the mucins of the non-secretor patient had not been found previously in the respiratory mucins; they are listed below. 相似文献
995.
Ethylene and fruit ripening 总被引:13,自引:0,他引:13
Jean-Marc Lelièvre Alain Latchè Brian Jones Mondher Bouzayen Jean-Claude Pech 《Physiologia plantarum》1997,101(4):727-739
The latest advances in our understanding of the relationship between ethylene and fruit ripening are reviewed. Considerable progress has been made in the characterisation of genes encoding the key ethylene biosynthetic enzymes, ACC synthase (ACS) and ACC oxidase (ACO) and in the isolation of genes involved in the ethylene signal transduction pathway, particularly those encoding ethylene receptors ( ETR ). These have allowed the generation of transgenic fruit with reduced ethylene production and the identification of the Nr tomato ripening mutant as an ethylene receptor mutant. Through these tools, a clearer picture of the role of ethylene in fruit ripening is now emerging. In climacteric fruit, the transition to autocatalytic ethylene production appears to result from a series of events where developmentally regulated ACO and ACS gene expression initiates a rise in ethylene production, setting in motion the activation of autocatalytic ethylene production. Differential expression of ACS and ACO gene family members is probably involved in such a transition. Finally, we discuss evidence suggesting that the NR ethylene perception and transduction pathway is specific to a defined set of genes expressed in ripening climacteric fruit and that a distinct ETR pathway regulates other ethylene-regulated genes in both immature and ripening climacteric fruit as well as in non-climacteric fruit. The emerging picture is one where both ethylene-dependent and -independent pathways coexist in both climacteric and non-climacteric fruits. Further work is needed in order to dissect the molecular events involved in individual ripening processes and to understand the regulation of the expression of both ethylene-dependent and -independent genes. 相似文献
996.
Differential accumulation of two glycine-rich proteins during cold-acclimation alfalfa 总被引:9,自引:0,他引:9
997.
Viviane Dumur Radj Gervais Jean-Marc Rigot Elisabeth Delomel-Vinner Bertrand Decaestecker Jean-Jacques Lafitte Philippe Roussel 《Human genetics》1996,97(1):7-10
To assess better the link between congenital bilateral absence of the vas deferens (CBAVD) and cystic fibrosis (CF), we compared sweat chloride values, analysis of the CFTR intron 8 poly(T) tract length and analysis of 10 exons in a population of 38 patients with CBAVD. The data indicate that this population can be divided into three groups of patients. In the first group of 15 patients with abnormal sweat chloride (> 60 mmol/l), the frequency of CF mutations is high. In the second group of 18 patients with equivocal sweat chloride (between 40 and 60 mmol/l), the frequency of the 5T variant is high; 6 patients have a F508 mutation and a 5T variant and 1 patient is homozygous for the 5T variant; a 5T variant has been detected in 3 other patients, and a F508 mutation in another patient. A third group of 5 patients is probably not related to CF: these patients have other congenital abnormalities of the urogenital tract, low chloride values (< 40 mmol/l) and apparently no abnormality of the CF gene. 相似文献
998.
Purification and characterization of a novel protease from culture filtrates of a Streptomyces sp. 总被引:2,自引:0,他引:2
999.
The variations of leaf carbohydrate concentration, carbon isotopediscrimination () of leaf soluble carbohydrate, gas-exchangeand growth during a soil drying cycle under 350 and 700 µmolmol-1 CO2 concentrations ([CO2]) inQuercus robur seedlings wereanalysed. In well-watered conditions, a doubling of [CO2] causedan increase of CO2 assimilation rate (A) ( +47%) and a decreaseof stomatal conductance for water vapour (g) (25%),anddoubled the intrinsic water-use efficiency (A/g). The valuesof A were not affected by elevated [CO2] which was consistentwith the 2-fold increase of A/g. Elevated [CO2 also significantlyincreased sucrose and starch leaf concentrations as well asaerial growth and plant dry weight. The stimulating effect ofCO2 enrichment on A and A/g was maintained in moderate droughtconditions, but disappeared in the most severe drought conditions.Drought induced an increase of hexose concentrations in both[CO2], but this effect was more pronounced under elevated [CO2],which may contribute to increase osmoregulation. From the onsetof drought, starch was depleted in both [CO2]. Carbon isotopediscrimination decreased in response to drought, which correspondedto an increase in A/g according to the two-step model of isotopicdiscrimination. In contrast, the A/g values derived from instantaneousleaf gas-exchange measurements decreased along the drying cycle.The discrepancy observed between the two independent estimatesof water-use efficiency is discussed in terms of time-scaleintegration. The results obtained with the isotopic approachusing soluble carbohydrate suggest a predominant stomatal limitationof CO2 assimilation in response to drought. Soil drying cycle,elevated CO2, leaf gas-exchange, leaf carbohydrate concentrations,carbon isotope discrimination, growth, Quercus robur. Key words: soil drying cycle, elevated CO2, leaf gas-exchange, leaf carbohydrate concentrations, carbon isotope discrimination, growth, Quercus robur 相似文献
1000.
Grard F. Blanchard Jean-Marc Guarini Philippe Gros Pierre Richard 《Journal of phycology》1997,33(5):723-728
The response of the photosynthetic capacity (Pmax) of microphytobenthos to short-term variations of temperature (in the range 5–35° C) was assessed on a seasonal basis. The relationship is described mathematically, and relevant physiological parameters are identified: PMAX, the maximum value of Pmax achieved at Topl, the optimum temperature. Estimated values of Topt do not change significantly throughout the year and remain close to 25° C. It is thus concluded that Topt is not influenced by seasonal variations in the daily range of mud surface temperature. Identical conclusions hold for Tmax (ca. 38° C), the thermal threshold beyond which no photosynthesis occurs. Conversely, PMA estimates exhibit substantial variability: PMAX (mean ± root mean square error) is highest in April (11.18 ± 0.42 [μg C · [μg Chl a]?1· h?1) during the beginning of the annual increase in temperature, photoperiod, and maximum irradiance and is lowest in December (3.04 ± 0.16 μg C · [μg Chl a]?1· h?l). From an ecological point of view, the short-term and seasonal variations of PMAX suggest that the microphytobenthic community takes advantage of the abiotic spring environmental conditions, allowing the onset of the bloom. Nevertheless, no “acclimation strategy” (i.e. shifts in Topt and Tmax that prevent temperature inhibition in summer or improve photosynthetic rates in winter) is apparent from our results. 相似文献