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1.
Genome-wide analysis of the SET DOMAIN GROUP family in grapevine   总被引:1,自引:0,他引:1  
The SET DOMAIN GROUP (SDG) proteins represent an evolutionarily-conserved family of epigenetic regulators present in eukaryotes and are putative candidates for the catalysis of lysine methylation in histones. Plant genomes analyses of this family have been performed in arabidopsis, maize, and rice and functional studies have shown that SDG genes are involved in the control of plant development. In this work, we describe the identification and structural characterization of SDG genes in the Vitis vinifera genome. This analysis revealed the presence of 33 putative SDG genes that can be grouped into different classes, as it has been previously described for plants. In addition to the SET domain, the proteins identified possessed other domains in the different classes. As part of our study regarding the growth and development of grapevine, we selected eight genes and their expression levels were analyzed in representative vegetative and reproductive organs of this species. The selected genes showed different patterns of expression during inflorescence and fruit development, suggesting that they participate in these processes. Furthermore, we showed that the expression of selected SDGs changes during viral infection, using as a model Grapevine Leafroll Associated Virus 3-infected symptomatic grapevine leaves and fruits. Our results suggest that developmental changes caused by this virus could be the result of alterations in SDG expression.  相似文献   
2.
The combined effect of ocean acidification and warming is expected to have significant effects on several traits of marine organisms. The gastropod Concholepas concholepas is a rocky shore keystone predator characteristic of the south-eastern Pacific coast of South America and an important natural resource exploited by small-scale artisanal fishermen along the coast of Chile and Peru. In this study, we used small juveniles of C. concholepas collected from the rocky intertidal habitats of southern Chile (39°S) to evaluate under laboratory conditions the potential consequences of projected near-future levels of ocean acidification and warming for important early ontogenetic traits. The individuals were exposed long-term (5.8 months) to contrasting pCO2 (ca. 500 and 1400 μatm) and temperature (15 and 19°C) levels. After this period we compared body growth traits, dislodgement resistance, predator-escape response, self-righting and metabolic rates. With respect to these traits there was no evidence of a synergistic interaction between pCO2 and temperature. Shell growth was negatively affected by high pCO2 levels only at 15°C. High pCO2 levels also had a negative effect on the predator-escape response. Conversely, dislodgement resistance and self-righting were positively affected by high pCO2 levels at both temperatures. High tenacity and fast self-righting would reduce predation risk in nature and might compensate for the negative effects of high pCO2 levels on other important defensive traits such as shell size and escape behaviour. We conclude that climate change might produce in C. concholepas positive and negative effects in physiology and behaviour. In fact, some of the behavioural responses might be a consequence of physiological effects, such as changes in chemosensory capacity (e.g. predator-escape response) or secretion of adhesive mucous (e.g. dislodgement resistance). Moreover, we conclude that positive behavioural responses may assist in the adaptation to negative physiological impacts, and that this may also be the case for other benthic organisms.  相似文献   
3.
This article contains a comparison of the profits of cultivating modern and traditional varieties of coconuts as a monocrop and as an intercrop, in ideal and in average growing conditions, with good and with average management. We carry out the analysis from a private (financial) and from a national (economic) perspective. The results show that intercropping generates more income than monocropping. In the conclusion we discuss why development organizations and Third World countries encourage monocropping.  相似文献   
4.
We have isolated RNA from sheep brain synaptosomes and mitochondria separated by an aqueous two-phase system composed of dextran and poly(ethylene glycol). RNA was fractionated through oligo(dT)-cellulose columns and analyzed by electrophoresis through agarose slab gels containing methylmercuric hydroxide and stained with ethidium bromide. The electrophoretic patterns of the poly(A)-containing RNA fraction from synaptosomes and mitochondria are very similar although some high molecular weight RNA species, clearly visible in the synaptosomal fraction, are scarcely detected in the mitochondrial preparations. The electrophoretic analysis of a cleaner RNA preparation from digitonin-treated free mitochondria (mitoplasts) showed that all the poly (A)-RNA species of the synaptosomal preparation are also present in mitoplast. These results strongly suggest that all the discrete poly(A)-RNA species identified in brain synaptosomes are of mitochondrial origin.  相似文献   
5.
Two protein factors binding to the regulatory region of the pea chlorophyl a/b binding protein gene AB80 have been identified. One of these factors is found only in green tissue but not in etiolated or root tissue. The second factor (denominated ABF-2) binds to a DNA sequence element that contains a direct heptamer repeat TCTCAAA. It was found that presence of both of the repeats is essential for binding. ABF-2 is present in both green and etiolated tissue and in roots and factors analogous to ABF-2 are present in several plant species. Computer analysis showed that the TCTCAAA motif is present in the regulatory region of several plant genes.  相似文献   
6.
7.
Pathology of the human pulmonary paracoccidioidomycosis   总被引:1,自引:1,他引:0  
Lungs of twelve patients with chronic paracoccidioidomycosis (Pb) were studied in an attempt to understand the pathogenesis of the pulmonary disease. Ribbons of the lung parenchyma including the hilar region and directed towards apical, basal and lateral regions were subdivided into sections from the hilar, intermediate and peripheral segments. The following histopathological reactions directly or indirectly related to P. brasiliensis were described and analysed in relation to the number of slides studied and the pulmonary region involved: (1) pneumonic reaction; (2) early granulomatous formation; (3) mature and healed granulomata; (4) mixed pattern (early and mature granuloma in the same pulmonary area visualized in the slide); (5) pulmonary fibrosis.It was concluded that chronic pulmonary Pb is a recurrent disease affecting equally both lungs. Fibrosis was connected mainly with the progressive evolution of the granulomata towards cicatrization and to a lesser degree probably to a direct induction by the fungi. Based chiefly on the tendency of the fibrosis to run around bronchi and to make up septa interconnecting bronchi and vessels it was hipothesized that these findings were the result of a previous chronic specific lymphangitis by the fungi. Hilar fibrosis would be the result of this lymphangitis and/or of the progression of the specific granulomatous reaction seen in the hilar lymph nodes.Non specific forms of arteritis and areas of destructive emphysema related to granulomatous inflammation and fibrosis were described. Three cases developed pulmonary hypertension.  相似文献   
8.
We have characterized a new tomato cDNA, TAS14, inducible by salt stress and abscisic acid (ABA). Its nucleotide sequence predicts an open reading frame coding for a highly hydrophilic and glycine-rich (23.8%) protein of 130 amino acids. Southern blot analysis of tomato DNA suggests that there is one TAS14 structural gene per haploid genome. TAS14 mRNA accumulates in tomato seedlings upon treatment with NaCl, ABA or mannitol. It is also induced in roots, stems and leaves of hydroponically grown tomato plants treated with NaCl or ABA. TAS14 mRNA is not induced by other stress conditions such as cold and wounding. The sequence of the predicted TAS14 protein shows four structural domains similar to the rice RAB21, cotton LEA D11 and barley and maize dehydrin genes.  相似文献   
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10.
A bacterium, Pseudomonas sp. strain C1S1, able to grow on 2,4,6-trinitrotoluene (TNT), 2,4- and 2,6-dinitrotoluene, and 2-nitrotoluene as N sources, was isolated. The bacterium grew at 30 degrees C with fructose as a C source and accumulated nitrite. Through batch culture enrichment, we isolated a derivative strain, called Pseudomonas sp. clone A, which grew faster on TNT and did not accumulate nitrite in the culture medium. Use of TNT by these two strains as an N source involved the successive removal of nitro groups to yield 2,4- and 2,6-dinitrotoluene, 2-nitrotoluene, and toluene. Transfer of the Pseudomonas putida TOL plasmid pWW0-Km to Pseudomonas sp. clone A allowed the transconjugant bacteria to grow on TNT as the sole C and N source. All bacteria in this study, in addition to removing nitro groups from TNT, reduced nitro groups on the aromatic ring via hydroxylamine to amino derivatives. Azoxy dimers probably resulting from the condensation of partially reduced TNT derivatives were also found.  相似文献   
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