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961.
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963.
M.N. Dourado P.F. Martins M.C. Quecine F.A. Piotto L.A. Souza M.R. Franco T. Tezotto R.A. Azevedo 《The Annals of applied biology》2013,163(3):494-507
Cadmium (Cd) can enter soil through the use of fertilisers, calcareous, pesticides and industrial and/or domestic effluents. Cd can leach into groundwater and be taken up by plants, potentially leading to reductions in plant growth and yield. In soil, plant roots interact with heavy metal (HM)‐tolerant microorganisms that may promote plant growth. Soil microorganisms may also be able to solubilise or mobilise soil metals, thereby acting as bioremediators. A better understanding of the interaction among plants, metals, microorganisms and soil will lead to improved plant tolerance. Two multi‐tolerant bacteria from the Burkholderia genus were isolated from Cd‐contaminated and Cd‐uncontaminated soil of a coffee plantation. In addition to its high tolerance to Cd, the strain SCMS54 produces indole‐acetic acid (IAA), solubilises inorganic phosphate and produces siderophores, demonstrating its potential to contribute to beneficial plant–microorganism interactions. When interacting with tomato plants exposed to Cd, the bacterium led to decreases in plant peroxide and chlorosis levels, promoted relative plant growth and decreased the root absorption of Cd, resulting in increased plant tolerance to this highly toxic HM. The results indicated that the inoculation of tomato plants with Burkholderia sp. SCMS54 promotes better growth in plants cultivated in the presence of Cd. This phenomenon appears to be attributed to a mechanism that decreases Cd concentrations in the roots via a beneficial interaction between the bacteria and the plant roots. 相似文献
964.
Jessica Tiedke Ceyda CubukThorsten Burmester 《Biochemical and biophysical research communications》2013
Animals in many aquatic ecosystems must cope with changing environmental parameters, such as temperature, oxygen availability or pH. We have investigated the molecular responses to acidification in the gills and body of zebrafish (Danio rerio) by means of quantitative real-time PCR. Expression levels of typical stress genes and genes for antioxidant defense were strongly enhanced in gills, and to lesser extents in the body, suggesting that acidification leads to oxidative stress. Surprisingly, the globins were found to be among the most prominent stress–responsive proteins in our study. Myoglobin showed the strongest response of all investigated genes in the gills, as confirmed by Western blotting. These findings agree with the role of globins in oxidative energy metabolism, but may also hint at a specific function in antioxidative defense. 相似文献
965.
966.
Guoguo Zhu Yingcheng Zheng Lianglu Zhang Yingying Shi Wenhua Li Zhongchun Liu Biwen Peng Jun Yin Wanhong Liu Xiaohua He 《Biochemical and biophysical research communications》2013
Coxsackievirus A16 (CA16) infection, which is responsible for hand, foot and mouth disease (HFMD), has become a common health problem in Asia due to the prevalence of the virus. Thus, it is important to understand the pathogenesis of CA16 infection. Viruses that induce endoplasmic reticulum (ER) stress are confronted with the unfolded protein response (UPR), which may lead to apoptotic cell death and influence viral replication. In this study, we found that CA16 infection could induce apoptosis and ER stress in RD cells. Interestingly, apoptosis via the activation of caspase-3, -8 and -9 in the extrinsic or intrinsic apoptotic pathways in RD cells was inhibited by 4-phenyl butyric acid (4PBA), a chemical chaperone that reduces ER stress. These results suggest that CA16 infection leads to ER stress, which in turn results in prolonged ER stress-induced apoptosis. This study provides a new basis for understanding CA16 infection and host responses. 相似文献
967.
Oxidative damage associated with obesity is prevented by overexpression of CuZn- or Mn-superoxide dismutase 总被引:1,自引:0,他引:1
Yuhong Liu Wenbo Qi Arlan Richardson Holly Van Remmen Yuji Ikeno Adam B. Salmon 《Biochemical and biophysical research communications》2013
The development of insulin resistance is the primary step in the etiology of type 2 diabetes mellitus. There are several risk factors associated with insulin resistance, yet the basic biological mechanisms that promote its development are still unclear. There is growing literature that suggests mitochondrial dysfunction and/or oxidative stress play prominent roles in defects in glucose metabolism. Here, we tested whether increased expression of CuZn-superoxide dismutase (Sod1) or Mn-superoxide dismutase (Sod2) prevented obesity-induced changes in oxidative stress and metabolism. Both Sod1 and Sod2 overexpressing mice were protected from high fat diet-induced glucose intolerance. Lipid oxidation (F2-isoprostanes) was significantly increased in muscle and adipose with high fat feeding. Mice with increased expression of either Sod1 or Sod2 showed a significant reduction in this oxidative damage. Surprisingly, mitochondria from the muscle of high fat diet-fed mice showed no significant alteration in function. Together, our data suggest that targeting reduced oxidative damage in general may be a more applicable therapeutic target to prevent insulin resistance than is improving mitochondrial function. 相似文献
968.
Genetic studies of social behaviour have currently received new impetus from models including indirect genetic effects (IGEs) of social partners. This study aimed at investigating the contribution of conspecifics in social dominance, considered as response of dyadic interaction that is, winning (dominant individual) or losing (subordinate). A genetic correlation of −1 is expected between the attitude to win and the attitude to loose, and because a population always accounts for half winners and half losers, the heritability of the dominant status should be close to zero. Specifically, social dominance was studied in Aosta Chestnut and Aosta Black Pied (Bos taurus) breeds, alpine rustic cattle famous for traditional tournaments where pairs of cows assess dominant status in bloodless fights. The outcomes of 25 590 dyadic interactions performed by 8159 individuals in 11 years were analysed by applying a classical quantitative model and models including indirect effects. Data were analysed via Bayesian approach on a threshold trait. The assessment of variances revealed a genetic correlation of −0.976 between direct and indirect genetic components. The heritability measured on a liability scale was 0.122 for direct phenotype, but decreased to 0.014 when the total heritable variance (TBV) was considered. The trend of estimated breeding values showed that the total TBV was constant over the years, even though its direct component increased and the indirect part decreased. This result confirms the relevance of IGEs on social behaviour and the assumption that the mean individual social dominance cannot evolve within a population, due to the evolutionary constraints imposed by the ‘social environment''. 相似文献
969.
Alexey V. Shpilyov Vladislav V. Zinchenko Bernhard Grimm Heiko Lokstein 《The Plant journal : for cell and molecular biology》2013,73(2):336-346
In oxygenic phototrophic organisms, the phytyl ‘tail’ of chlorophyll a is formed from a geranylgeranyl residue by the enzyme geranylgeranyl reductase. Additionally, in oxygenic phototrophs, phytyl residues are the tail moieties of tocopherols and phylloquinone. A mutant of the cyanobacterium Synechocystis sp. PCC 6803 lacking geranylgeranyl reductase, ΔchlP, was compared to strains with specific deficiencies in either tocopherols or phylloquinone to assess the role of chlorophyll a phytylatation (versus geranylgeranylation). The tocopherol‐less Δhpt strain grows indistinguishably from the wild‐type under ‘standard’ light photoautotrophic conditions, and exhibited only a slightly enhanced rate of photosystem I degradation under strong irradiation. The phylloquinone‐less ΔmenA mutant also grows photoautotrophically, albeit rather slowly and only at low light intensities. Under strong irradiation, ΔmenA retained its chlorophyll content, indicative of stable photosystems. ΔchlP may only be cultured photomixotrophically (due to the instability of both photosystems I and II). The increased accumulation of myxoxanthophyll in ΔchlP cells indicates photo‐oxidative stress even under moderate illumination. Under high‐light conditions, ΔchlP exhibited rapid degradation of photosystems I and II. In conclusion, the results demonstrate that chlorophyll a phytylation is important for the (photo)stability of photosystems I and II, which, in turn, is necessary for photoautotrophic growth and tolerance of high light in an oxygenic environment. 相似文献
970.