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1.
Ana Rodríguez Takehiko Shimada Magdalena Cervera Ana Redondo Berta Alquézar María Jesús Rodrigo Lorenzo Zacarías Lluís Palou María M López Leandro Pe?a 《Plant signaling & behavior》2015,10(6)
Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores. 相似文献
2.
Miguel Angel Pujana Monica Gratacós Jordi Corral Isabel Banchs Aurora Sánchez David Genís Carlos Cervera Víctor Volpini X. Estivill 《Human genetics》1997,101(1):18-21
Genetic anticipation – increasing severity and a decrease in the age of onset with successive generations of a pedigree –
is clearly present in autosomal dominant cerebellar ataxia (ADCA). Anticipation is correlated with expansion of the CAG/CTG
repeat sequence to sizes above those in the normal range through the generations of a pedigree. Genetic heterogeneity has
been demonstrated for ADCA, with four cloned genes (SCA1, SCA2, SCA3/MJD, and SCA6) and three mapped loci (SCA4, SCA5 and
SCA7). Another related dominant ataxia, dentatorubral-pallidoluysian atrophy (DRPLA), presents anticipation with CAG/CTG repeat
expansions. We had previously analysed ADCA patients who had not shown repeat expansions in cloned genes for CAG/CTG repeat
expansions by the repeat expansion detection method (RED) and had detected expansions of between 48 and 88 units in 17 unrelated
familial cases. We present here an analysis of 13 genes and expressed sequence tags (ESTs) containing 10 or more CAG/ CTG
repeat sequences selected from public databases in the 17 unrelated ADCA patients. Of the 13 selected genes and ESTs, 9 were
found to be polymorphic with heterozygosities ranging between 0.09 and 0.80 and 2 to 17 alleles. In ADCA patients none of
the loci showed expansions above the normal range of the CAG/CTG repeat sequences, excluding them as the mutation causing
ADCA.
Received: 28 May 1997 / Accepted: 30 June 1997 相似文献
3.
Judyta Kruk Irena Baranowska Bogusaw Buszewski Sylwia Bajkacz Bartosz Kowalski Magdalena Ligor 《Chirality》2019,31(2):138-149
Plant material is a rich source of valuable compounds such as flavanones. Their different forms influence bioavailability and biological activity, causing problems with the selection of plant material for specific purposes. The purpose of this research was to determine selected flavanone (eriodictyol, naringenin, liquiritigenin, and hesperetin) enantiomer contents in free form and bonded to glycosides by an RP‐UHPLC‐ESI‐MS/MS method. Different parts (stems, leaves, and flowers) of goldenrod (Solidago virgaurea L.), lucerne (Medicago sativa L.), and phacelia (Phacelia tanacetifolia Benth.) were used. The highest content of eriodictyol was found in goldenrod flowers (13.1 μg/g), where it occurred mainly as the (S)‐enantiomer, and the greatest proportion of the total amount was bonded to glycosides. The richest source of naringenin was found to be lucerne leaves (4.7 μg/g), where it was mainly bonded to glycosides and with the (S)‐enantiomer as the dominant form. Liquiritigenin was determined only in lucerne, where the flowers contained the highest amount (1.2 μg/g), with the (R)‐enantiomer as dominant aglycone form and the (S)‐enantiomer as the dominant glycosylated form. The highest hesperetin content was determined in phacelia leaves (0.38 μg/g), where it was present in the form of a glycoside and only as the (S)‐enantiomer. A comparison of the different analyte forms occurring in different plant parts was performed for the first time. 相似文献
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Izabela Krzemińska Barbara Pawlik-Skowrońska Magdalena Trzcińska Jerzy Tys 《Bioprocess and biosystems engineering》2014,37(4):735-741
The effect of different photoperiods: 24 h illumination and a 12:12-h light/dark (12L:12D) cycle on the growth rate and biomass productivity was studied in five algal species: Neochloris conjuncta, Neochloris terrestris, Neochloris texensis, Botryococcus braunii and Scenedesmus obliquus. The green microalgae examined differ in the reproduction mode. Continuous illumination stimulated the growth of B. braunii and S. obliquus more effectively than the growth of the microalgal species from the genus Neochloris. However, under shorter duration of light of the same intensity (12L:12D cycle), the growth of all the three species of Neochloris was stimulated. Under continuous illumination, the specific growth rate in the first phase of B. braunii and S. obliquus cultures was higher than the growth rate of Neochloris, whereas under the 12L:12D cycle, the specific growth rate of all the three Neochloris species was generally higher than that in B. braunii and S. obliquus. As a result, the light regime influenced algal biomass productivity differently. The maximum biomass productivity was obtained in B. braunii and S. obliquus cultures carried out at continuous illumination. All the Neochloris species produced biomass more efficiently at the 12L:12D cycle, which was two–threefold higher than that of B. braunii and S. obliquus. The unicellular species of the green microalgae from the genus Neochloris, examined for the first time in this study, are promising prospective objects for algal biotechnology. 相似文献
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Stereologic techniques were used to analyse the density and distribution of Concanavalin-A (Con-A) receptor sites on the surface of isolated resting human peripheral-blood T lymphocytes using Con-A/colloidal-gold-labelled horseradish peroxidase. The T-lymphocyte surface appeared to be composed of microvilli, smooth areas and uncoated pits. Coated pits and coated vesicles, identified by the preferential staining of clathrin-containing membranes (tannic-acid/saponin fixation), were scarce. Quantitative analysis of the gold labelling on T lymphocytes after glutaraldehyde fixation indicated the presence of 2.13 +/- 0.46 gold particles per micron of cell surface and that these particles were preferentially located on uncoated pits. These results suggest the existence of cell-surface domains for these receptor sites in human resting T lymphocytes. 相似文献
8.
During cortical development, neurons generated at the same time in the ventricular zone migrate out into the cortical plate and form a cortical layer (Berry and Eayrs, 1963, Nature 197:984–985; Berry and Rogers, 1965, J. Anat. 99:691–709). We have been studying both the formation and maintenance of cortical layers in slice cultures from rat cortex. The bromodexyuridine (BrdU) method was used to label cortical neurons on their birthday in vivo. When slice cultures were prepared from animals at different embryonic and postnatal ages, all cortical layers that have already been established in vivo remained preserved for several weeks in vitro. In slice cultures prepared during migration in the cortex, cells contiuned to migrate towards the pial side of the cortical slice, however, migration ceased after about 1 week in culture. Thus, cortical cells reached their final laminar position only in slice cultures from postnatal animals, whereas in embryonic slices, migrating cells became scattered throughout the cortex. Previous studies demonstrated that radial glia fibers are the major substrate for migrating neurons (Rakic, 1972, J. Comp. Neurol. 145:61–84; Hatten and Mason, 1990, Experientia 46:907–916). Using antibodies directed against the intermediate filament Vimentin, radial glial cells were detected in all slice cutures where cell migration did occur. Comparable to the glia development in vivo, radial glial fibers disappeared and astrocytes containing the glia fibrillary-associated protein (GFAP) differentiated in slice cultures from postnatal cortex, after the neurons have completed their migration. In contrast, radial glial cells were detected over the whole culture period, and very few astrocytes differentiated in embryonic slices, where cortical neurons failed to finish their migration. The results of this study indicate that the local environment is sufficient to sustain the layered organization of the cortex and support the migration of cortical neurons. In addition, our results reveal a close relationship between cell migration and the developmental status of glial cells. © 1992 John Wiley & Sons, Inc. 相似文献
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