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1.
BMC Plant Biol ; 24(1): 86, 2024 Feb 03.
Article de Anglais | MEDLINE | ID: mdl-38310225

RÉSUMÉ

BACKGROUND: Early selection in tree breeding could be achieved by addressing the longevity of tree improvement activities. Genetic parameter changes and age-age correlations are essential for determining the optimal timing of early selection. Practical tracking of genetic parameters of Pinus koraiensis, a major timber species with economic and ecological value, has become feasible as its progeny testing has entered the mid-term age in Korea. However, research on the age-age correlation of P. koraiensis as progeny trials approach rotation age is limited. This study aimed to investigate genetic parameter trends and age-age correlations in P. koraiensis progeny. P. koraiensis progeny were assessed at two sites using a linear mixed-effects model with two-dimensional spatial autoregressive structure. Height, diameter, and volume growth were measured in 11 assessments over 40 years. RESULTS: Genetic parameters, such as height and diameter, showed different patterns of change. The heritability ranged for the three growth traits in 0.083-0.710, 0.288-0.781, and 0.299-0.755 across the sites and age. Height heritability and its coefficient of variance decreased, whereas the diameter and volume estimates remained relatively constant. Correlations with Age 40 for phenotypic, genetic, and rank of breeding values ranged between 0.16 and 0.92, 0.594 and 0.988, and 0.412 and 0.965, respectively. These correlations generally increased as the age approached Age 40, with particularly high levels observed at Age 26 and Age 30. CONCLUSION: The observed genetic trends in P. koraiensis progeny testing offer valuable insights for early and precise selection. Notably, selecting superior genotypes at Ages 26-30 is supported by discernible genetic gains and robust correlations. Future research should integrate unbalanced data for selecting mother trees or families and conduct a comprehensive economic analysis of early selection to validate its practical benefits.


Sujet(s)
Forêts , Pinus , Humains , Adulte , Pinus/génétique , Amélioration des plantes , Arbres , Phénotype
2.
Front Genet ; 14: 1289557, 2023.
Article de Anglais | MEDLINE | ID: mdl-38028631

RÉSUMÉ

The glycolytic pathway involves phosphofructokinase (PFK), a rate-limiting enzyme that catalyzes the phosphorylation of fructose-6-phosphate. In plants, the two PFK members are ATP-dependent phosphofructokinase (PFK) and pyrophosphate-fructose-6-phosphate phosphotransferase (PFP). However, the functions of the PFK family members in Quercus rubra are not well understood. The purpose of this study was to investigate the genome-wide distribution of the PFK family members and their roles in Q. rubra by performing a systematic study of the phylogenetic relationships, molecular characteristics, motifs, chromosomal and subcellular locations, and cis-elements of QrPFKs. We identified 14 QrPFK genes in the genome of Q. rubra, followed by examining their expression in different tissues, including the roots, stems, and leaves. The phylogenetic tree divided the 14 QrPFK genes into two groups: 11 belonging to PFK and three belonging to PFP. The expression profiles of all 14 proteins were relatively the same in leaves but differed between stems and roots. Four genes (Qurub.02G189400.1, Qurub.02G189400.2, Qurub.09G134300.1, and Qurub.09G134300.2) were expressed at very low levels in both stems and roots, while two (Qurub.05G235500.1 and Qurub.05G235500.1) were expressed at low levels and the others showed relatively high expression in all tissues.

3.
Plants (Basel) ; 12(18)2023 Sep 12.
Article de Anglais | MEDLINE | ID: mdl-37765403

RÉSUMÉ

Drought stress affects plant productivity by altering plant responses at the morphological, physiological, and molecular levels. In this study, we identified physiological and genetic responses in Populus alba × Populus glandulosa hybrid clones 72-30 and 72-31 after 12 days of exposure to drought treatment. After 12 days of drought treatment, glucose, fructose, and sucrose levels were significantly increased in clone 72-30 under drought stress. The Fv/Fo and Fv/Fm values in both clones also decreased under drought stress. The changes in proline, malondialdehyde, and H2O2 levels were significant and more pronounced in clone 72-30 than in clone 72-31. The activities of antioxidant-related enzymes, such as catalase and ascorbate peroxidase, were significantly higher in the 72-31 clone. To identify drought-related genes, we conducted a transcriptomic analysis in P. alba × P. glandulosa leaves exposed to drought stress. We found 883 up-regulated and 305 down-regulated genes in the 72-30 clone and 279 and 303 in the 72-31 clone, respectively. These differentially expressed genes were mainly in synthetic pathways related to proline, abscisic acid, and antioxidants. Overall, clone 72-31 showed better drought tolerance than clone 72-30 under drought stress, and genetic changes also showed different patterns.

4.
Plants (Basel) ; 11(24)2022 Dec 15.
Article de Anglais | MEDLINE | ID: mdl-36559641

RÉSUMÉ

Physiological response and transcriptome changes were observed to investigate the effects on the growth, metabolism and genetic changes of Pinus densiflora grown for a long time in an environment with an elevated atmospheric CO2 concentration. Pine trees were grown at ambient (400 ppm) and elevated (560 ppm and 720 ppm) CO2 concentrations for 10 years in open-top chambers. The content of nonstructural carbohydrates was significantly increased in elevated CO2. It was notable that the contents of chlorophylls significantly decreased at an elevated CO2. The activities of antioxidants were significantly increased at an elevated CO2 concentration of 720 ppm. We analyzed the differences in the transcriptomes of Pinus densiflora at ambient and elevated CO2 concentrations and elucidated the functions of the differentially expressed genes (DEGs). RNA-Seq analysis identified 2415 and 4462 DEGs between an ambient and elevated CO2 concentrations of 560 ppm and 720 ppm, respectively. Genes related to glycolysis/gluconeogenesis and starch/sucrose metabolism were unchanged or decreased at an elevated CO2 concentration of 560 ppm and tended to increase at an elevated CO2 concentration of 720 ppm. It was confirmed that the expression levels of genes related to photosynthesis and antioxidants were increased at an elevated CO2 concentration of 720 ppm.

5.
J Plant Physiol ; 268: 153584, 2022 Jan.
Article de Anglais | MEDLINE | ID: mdl-34890847

RÉSUMÉ

Down-regulation of leaf N and Rubisco under elevated CO2 (eCO2) are accompanied by increased non-structural carbohydrates (NSC) due to the sink-source imbalance. Here, to investigate whether the canopy position affects the down-regulation of Rubisco, we measured leaf N, NSC and N allocation in two species with different heights at maturity [Fraxinus rhynchophylla (6.8 ± 0.3 m) and Sorbus alnifolia (3.6 ± 0.2 m)] from 2017 to 2019. Since 2009, both species were grown at three different CO2 concentrations in open-top chambers: ambient CO2 (400 ppm; aCO2); ambient CO2 × 1.4 (560 ppm; eCO21.4); and ambient CO2 × 1.8 (720 ppm; eCO21.8). Leaf N per unit mass (Nmass) decreased under eCO2, except under eCO21.8 in S. alnifolia and coincided with increased NSC. NSC increased under eCO2 in F. rhynchophylla, but the increment of NSC was greater in the upper canopy of S. alnifolia. Conversely, Rubisco content per unit area was reduced under eCO2 in S. alnifolia and there was no interaction between CO2 and canopy position. In contrast, the reduction of Rubisco content per unit area was greater in the upper canopy of F. rhynchophylla, with a significant interaction between CO2 and canopy position. Rubisco was negatively correlated with NSC only in the upper canopy of F. rhynchophylla, and at the same NSC, Rubisco was lower under eCO2 than under aCO2. Contrary to Rubisco, chlorophyll increased under eCO2 in both species, although there was no interaction between CO2 and canopy position. Finally, photosynthetic N content (Rubisco + chlorophyll + PSII) was reduced and consistent with down-regulation of Rubisco. Therefore, the observed Nmass reduction under eCO2 was associated with dilution due to NSC accumulation. Moreover, down-regulation of Rubisco under eCO2 was more sensitive to NSC accumulation in the upper canopy. Our findings emphasize the need for the modification of the canopy level model in the context of climate change.


Sujet(s)
Carbone/métabolisme , Azote/métabolisme , Photosynthèse , Ribulose bisphosphate carboxylase , Arbres , Dioxyde de carbone , Chlorophylle , Fraxinus , Feuilles de plante/métabolisme , Ribulose bisphosphate carboxylase/métabolisme , Sorbus , Arbres/croissance et développement , Arbres/métabolisme
6.
J Plant Physiol ; 265: 153489, 2021 Oct.
Article de Anglais | MEDLINE | ID: mdl-34416600

RÉSUMÉ

Down-regulation of photosynthesis under elevated CO2 (eCO2) concentrations could be attributed to the depletion of nitrogen (N) availability after long-term exposure to eCO2 (progressive nitrogen limitation, PNL) or leaf N dilutions due to excessive accumulation of nonstructural carbohydrates. To determine the mechanism underlying this down-regulation, we investigated N availability, photosynthetic characteristics, and N allocation in leaves of Pinus densiflora (shade-intolerant species, evergreen tree), Fraxinus rhynchophylla (intermediate shade-tolerant species, deciduous tree), and Sorbus alnifolia (shade-tolerant species, deciduous tree). The three species were grown under three different CO2 concentrations in open-top chambers, i.e., ambient 400 ppm (aCO2); ambient × 1.4, 560 ppm (eCO21.4); and ambient × 1.8, 720 ppm (eCO21.8), for 11 years. Unlike previous studies that addressed PNL, after 11 years of eCO2 exposure, N availability remained higher under eCO21.8, and chlorophyll and photosynthetic N use efficiency increased under eCO2. In the case of nonstructural carbohydrates, starch and soluble sugar showed significant increases under eCO2. The maximum carboxylation rate, leaf N per mass (Nmass), and ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) were low under eCO21.8. The ratio of RuBP regeneration to the carboxylation rate as well as that of chlorophyll N to Rubisco N increased with CO2 concentrations. Based on the reduction in Nmass (not in Narea) that was diluted by increase in nonstructural carbohydrate, down-regulation of photosynthesis was found to be caused by the dilution rather than PNL. The greatest increases in chlorophyll under eCO2 were observed in S. alnifolia, which was the most shade-tolerant species. This study could help provide more detailed, mechanistically based processes to explain the down-regulation of photosynthesis by considering two hypotheses together and showed N allocation seems to be flexible against changes in CO2 concentration.


Sujet(s)
Adaptation oculaire/physiologie , Dioxyde de carbone/effets indésirables , Régulation négative/physiologie , Azote/métabolisme , Photosynthèse/physiologie , Feuilles de plante/métabolisme , Fraxinus/physiologie , Pinus/physiologie , Ribulose bisphosphate carboxylase/métabolisme , Sorbus/physiologie
7.
Sci Rep ; 8(1): 16935, 2018 11 16.
Article de Anglais | MEDLINE | ID: mdl-30446714

RÉSUMÉ

Online mind-body training (MBT) programs can improve the psychological capabilities of practitioners. Although there has been a lot of effort to understand the neural mechanisms underlying the therapeutic effects of meditation, little is known about changes in electroencephalographic (EEG) functional connectivity that accompany mind-body training. The present study aimed to investigate how an online MBT program alters EEG functional connectivity in the default mode network (DMN). We assessed a group of healthcare providers, including 14 females who participated in the 4-week MBT program and 15 females who underwent a 4-week of waiting period. EEG data and information about psychological states were obtained at baseline and 4 weeks. The result was that the intervention group showed significant reductions in anxiety and trait anger that were accompanied by increased global DMN network strengths in the theta and alpha (but not beta and delta) frequency bands; these changes were not observed in the control group. Other variables including state anger, positive and negative affect, and self-esteem have not been changed over time in both groups. These findings suggest that practicing the mind-body training could have a relevance to the functional differences in network related to stress and anxiety reaction.


Sujet(s)
Encéphale/physiopathologie , Enseignement à distance , Thérapies corps-esprit , Analyse de variance , Cartographie cérébrale , Électroencéphalographie , Humains , Imagerie par résonance magnétique , Thérapies corps-esprit/méthodes
8.
Phys Rev E ; 95(5-1): 052319, 2017 May.
Article de Anglais | MEDLINE | ID: mdl-28618580

RÉSUMÉ

The organization of international trades is highly complex under the collective efforts towards economic profits of participating countries given inhomogeneous resources for production. Considering the trade flux as the probability of exporting a product from a country to another, we evaluate the entropy of the world trades in the period 1950-2000. The trade entropy has increased with time, and we show that it is mainly due to the extension of trade partnership. For a given number of trade partners, the mean trade entropy is about 60% of the maximum possible entropy, independent of time, which can be regarded as a characteristic of the trade fluxes' heterogeneity and is shown to be derived from the scaling and functional behaviors of the universal trade-flux distribution. The correlation and time evolution of the individual countries' gross-domestic products and the number of trade partners show that most countries achieved their economic growth partly by extending their trade relationship.

9.
Org Biomol Chem ; 6(8): 1498-501, 2008 Apr 21.
Article de Anglais | MEDLINE | ID: mdl-18385856

RÉSUMÉ

A concise, stereocontrolled synthesis of (+)-polyoxamic acid was achieved. Starting from trans-oxazoline as a chiral building block, the key step involves diastereoselective oxazine formation catalyzed by palladium(0).


Sujet(s)
Acides aminés/synthèse chimique , Oxazines/synthèse chimique , Oses acides/synthèse chimique , Acides aminés/composition chimique , Conformation moléculaire , Oxazines/composition chimique , Stéréoisomérie , Oses acides/composition chimique
10.
11.
Chemosphere ; 65(4): 541-6, 2006 Oct.
Article de Anglais | MEDLINE | ID: mdl-16603226

RÉSUMÉ

We investigated alleviation of Cd toxicity and changes in the physiological characteristics of Betula schmidtii seedlings following application of composted sewage sludge to Cd-treated plants. Plants were grown under four test conditions: control, Cd treatment, sludge amendment, and Cd treatment with sludge amendment. B. schmidtii treated with Cd only accumulated the greatest amount of Cd in the leaves, but absorbed Cd was also highly concentrated in the roots. In contrast, Cd concentrations in the Cd and sludge amendment treated seedlings were the lowest in the roots. Since sludge amendment increased the growth of seedlings, it may have alleviated toxicity by dilution of Cd. Additionally, the absorbed Cd was more widely distributed since it was transported from the roots and accumulated in the stems and leaves of Cd and sludge treated plants. Cd treatment inhibited the growth and physiological functions of B. schmidtii seedlings, but sludge amendment compensated for these effects and improved growth and physiological functions in both Cd-treated and control plants. SOD activity in the leaves of seedlings was increased in the Cd-treated plants, but not in the Cd and sludge amendment treated seedlings. In conclusion, alleviation of Cd toxicity in response to sludge amendment may be related to a dilution effect, in which the Cd concentration in the tissues was effectively lowered by the improved growth performance of the seedlings.


Sujet(s)
Betula/croissance et développement , Cadmium/toxicité , Engrais , Eaux d'égout/composition chimique , Polluants du sol/toxicité , Betula/effets des médicaments et des substances chimiques , Betula/enzymologie , Chlorophylle/métabolisme , Photosynthèse/effets des médicaments et des substances chimiques , Plant/effets des médicaments et des substances chimiques , Plant/enzymologie , Plant/croissance et développement , Superoxide dismutase/métabolisme
12.
Arch Pharm Res ; 28(2): 151-8, 2005 Feb.
Article de Anglais | MEDLINE | ID: mdl-15789742

RÉSUMÉ

Palladium(II)-catalyzed carboxylation of chiral olefins 6a-d has been examined under various conditions. In the weak basic condition (K2CO3), 7a-d were obtained in good yields. Alternatively, in the strong basic condition, pyrrolidinones 8a-d were obtained resulting in excellent yields and with high diastereoselectivity.


Sujet(s)
Antinéoplasiques/synthèse chimique , Antinéoplasiques/pharmacologie , Pyrrolidones/synthèse chimique , Pyrrolidones/pharmacologie , Alcènes/composition chimique , Catalyse , Chromatographie sur gel , Indicateurs et réactifs , Spectroscopie par résonance magnétique , Palladium/composition chimique , Solvants , Stéréoisomérie
13.
Arch Pharm Res ; 27(2): 136-42, 2004 Feb.
Article de Anglais | MEDLINE | ID: mdl-15022712

RÉSUMÉ

In this study, a highly diastereoselective synthesis of anti-1,2-aminoalcohol was explored starting from L-amino acids as chiral sources. The higher yield and diastereoselectivity was shown when the aza-Claisen rearrangement was performed with allylic trichloroacetimidate 6a in the presence of palladium(II) catalyst.


Sujet(s)
Aminoalcools/synthèse chimique , Composés aza/composition chimique , Palladium/composition chimique , Catalyse , Hydroxylation , Indicateurs et réactifs , Stéréoisomérie
14.
Org Lett ; 4(25): 4403-5, 2002 Dec 12.
Article de Anglais | MEDLINE | ID: mdl-12465898

RÉSUMÉ

[reaction: see text] A concise, stereocontrolled synthesis of sphingofungin F was achieved. Key features involve diastereoselective oxazoline formation catalyzed by palladium(0), MgBr(2)-promoted gamma-alkoxy allylic stannane addition, and palladium(0)-catalyzed coupling of a vinyl iodide with an organozinc reagent.


Sujet(s)
Acides aminés/composition chimique , Acides aminés/synthèse chimique , Antifongiques/composition chimique , Antifongiques/synthèse chimique , Acides gras insaturés/composition chimique , Acides gras insaturés/synthèse chimique , Catalyse , Structure moléculaire , Palladium/composition chimique , Stéréoisomérie
16.
Arch Pharm Res ; 25(1): 49-52, 2002 Feb.
Article de Anglais | MEDLINE | ID: mdl-11885691

RÉSUMÉ

Syntheses of (+/-)-homoepibatidine analogues (2), which contain the 8-azabicyclo [3.2.1]octane ring system, were achieved by using palladium-catalyzed reductive-coupling reaction from 3 and the analgesic activity was tested by Mouse writhing antinociceptive assay.


Sujet(s)
Analgésiques non narcotiques/synthèse chimique , Composés hétérocycliques bicycliques/synthèse chimique , Agonistes nicotiniques/synthèse chimique , Pyridines/synthèse chimique , Analgésiques non narcotiques/pharmacologie , Animaux , Composés hétérocycliques bicycliques/pharmacologie , Catalyse , Indicateurs et réactifs , Spectroscopie par résonance magnétique , Mâle , Souris , Souris de lignée ICR , Agonistes nicotiniques/pharmacologie , Palladium , Pyridines/pharmacologie
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