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71.
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Exploring natural variation of Pinus pinaster Aiton using metabolomics: Is it possible to identify the region of origin of a pine from its metabolites? 下载免费PDF全文
Mónica Meijón Isabel Feito Michal Oravec Carolina Delatorre Wolfram Weckwerth Juan Majada Luis Valledor 《Molecular ecology》2016,25(4):959-976
Natural variation of the metabolome of Pinus pinaster was studied to improve understanding of its role in the adaptation process and phenotypic diversity. The metabolomes of needles and the apical and basal section of buds were analysed in ten provenances of P. pinaster, selected from France, Spain and Morocco, grown in a common garden for 5 years. The employment of complementary mass spectrometry techniques (GC‐MS and LC‐Orbitrap‐MS) together with bioinformatics tools allowed the reliable quantification of 2403 molecular masses. The analysis of the metabolome showed that differences were maintained across provenances and that the metabolites characteristic of each organ are mainly related to amino acid metabolism, while provenances were distinguishable essentially through secondary metabolism when organs were analysed independently. Integrative analyses of metabolome, environmental and growth data provided a comprehensive picture of adaptation plasticity in conifers. These analyses defined two major groups of plants, distinguished by secondary metabolism: that is, either Atlantic or Mediterranean provenance. Needles were the most sensitive organ, where strong correlations were found between flavonoids and the water regime of the geographic origin of the provenance. The data obtained point to genome specialization aimed at maximizing the drought stress resistance of trees depending on their origin. 相似文献
73.
The contribution of Erich von Tschermak-Seysenegg (1871?C1962) to the beginning of classical genetics is a matter of dispute. The aim of this study is to analyse, based on newly accessible archive materials, the relevance of his positions and theoretical views in a debate between advocates of early Mendelian explanation of heredity and proponents of biometry, which took place in England around 1901?C1906. We challenge not only his role of an ??external consultant??, which at the time de facto confirmed his status of ??rediscoverer?? of Mendel??s work but also analyse his ambivalent positions which are to be seen as a part of ??further development?? (Weiterführung), a development of Mendel??s legacy as he understood it. Second, there is an interesting aspect of establishing connections within an ??experimental culture?? along the Mendel??s lines of thought that was parallel to the first step of institutionalizing the new discipline of Genetics after 1905/06. Part of the study is also the analysis of contribution of his older brother Armin von Tschermak-Seysenegg (1870?C1952) who??much like in the case of ??rediscovery?? of 1900?C1901??was for his younger brother an important source of theoretical knowledge. In this particular case, it regarded Bateson??s ??Defence?? of Mendel from 1902. 相似文献
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Ido Wolf Shiri Shahmoon Michal Ben Ami Yael Levy-Shraga Kineret Mazor-Aronovitch Orit Pinhas-Hamiel Yonatan Yeshayahu Rina Hemi Hannah Kanety Tami Rubinek Dalit Modan-Moses 《PloS one》2014,9(9)
Objective
Klotho is an aging-modulating protein expressed mainly in the kidneys and choroid plexus, which can also be shed, released into the circulation and act as a hormone. Klotho deficient mice are smaller compared to their wild-type counterparts and their somatotropes show marked atrophy and reduced number of secretory granules. Recent data also indicated an association between klotho levels and growth hormone (GH) levels in acromegaly. We aimed to study the association between klotho levels and GH deficiency (GHD) in children with growth impairment.Design
Prospective study comprising 99 children and adolescents (aged 9.0±3.7 years, 49 male) undergoing GH stimulation tests for short stature (height-SDS = −2.1±0.6). Klotho serum levels were measured using an α-klotho ELISA kit.Results
Klotho levels were significantly lower (p<0.001) among children with organic GHD (n = 11, 727±273 pg/ml) compared to both GH sufficient participants (n = 59, 1497±754 pg/ml) and those with idiopathic GHD (n = 29, 1645±778 pg/ml). The difference between GHS children and children with idiopathic GHD was not significant. Klotho levels positively correlated with IGF-1- standard deviation scores (SDS) (R = 0.45, p<0.001), but were not associated with gender, pubertal status, age or anthropometric measurements.Conclusions
We have shown, for the first time, an association between low serum klotho levels and organic GHD. If validated by additional studies, serum klotho may serve as novel biomarker of organic GHD. 相似文献76.
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Telleria J Lafay B Virreira M Barnabé C Tibayrenc M Svoboda M 《Experimental parasitology》2006,114(4):279-288
The comparisons of 170 sequences of kinetoplast DNA minicircle hypervariable region obtained from 19 stocks of Trypanosoma cruzi and 2 stocks of Trypanosoma cruzi marenkellei showed that only 56% exhibited a significant homology one with other sequences. These sequences could be grouped into homology classes showing no significant sequence similarity with any other homology group. The 44% remaining sequences thus corresponded to unique sequences in our data set. In the DTU I ("Discrete Typing Units") 51% of the sequences were unique. In contrast, in the DTU IId, 87.5% of sequences were distributed into three classes. The results obtained for T. cruzi marinkellei, showed that all sequences were unique, without any similarity between them and T. cruzi sequences. Analysis of palindromes in all sequence sets show high frequency of the EcoRI site. Analysis of repetitive sequences suggested a common ancestral origin of the kDNA. The editing mechanism that occurs in kinetoplastidae is discussed. 相似文献
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Calreticulin is a Ca2+-buffering ER chaperone that also modulates cell adhesiveness. In order to study the effect of calreticulin on the expression
of adhesion-related genes, we created a calreticulin inducible Human Embryonic Kidney (HEK) 293 cell line. We found that fibronectin
mRNA and both intra- and extra-cellular fibronectin protein levels increased following calreticulin induction. However, despite
this increase in fibronectin, HEK293 cells did not assemble an extracellular fibrillar fibronectin matrix regardless of the
level of calreticulin expression. Furthermore, HEK293 cells exhibited a poorly organized actin cytoskeleton, did not have
clustered fibronectin receptors at the cell surface, and did not form focal contacts. This likely accounts for the lack of
fibronectin matrix deposition by these cells regardless of calreticulin expression level. Vinculin abundance did not appreciably
increase upon calreticulin induction and the level of active c-Src, a regulatory kinase of focal contacts, was found to be
abundant and unregulated by calreticulin induction in these cells. The inability to form stable focal contacts and to commence
fibronectin fibrillogenesis due to high c-Src activity may be responsible for the poor adhesive phenotype of HEK 293 cells.
Thus, we show here that HEK293 cells are not suitable for microscopical studies of cell-substratum adhesions, but are best
suited for biochemical studies.
S. Papp and M. P. Fadel have contributed equally to this work. 相似文献