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151.
152.
Zuzana Majkova Michal Toborek Bernhard Hennig 《Journal of cellular and molecular medicine》2010,14(10):2359-2370
Complications of vascular diseases, including atherosclerosis, are the number one cause of death in Western societies. Dysfunction of endothelial cells is a critical underlying cause of the pathology of atherosclerosis. Lipid rafts, and especially caveolae, are enriched in endothelial cells, and down-regulation of the caveolin-1 gene may provide protection against the development of atherosclerosis. There is substantial evidence that exposure to environmental pollution is linked to cardiovascular mortality, and that persistent organic pollutants can markedly contribute to endothelial cell dysfunction and an increase in vascular inflammation. Nutrition can modulate the toxicity of environmental pollutants, and evidence suggests that these affect health and disease outcome associated with chemical insults. Because caveolae can provide a regulatory platform for pro-inflammatory signalling associated with vascular diseases such as atherosclerosis, we suggest a link between atherogenic risk and functional changes of caveolae by environmental factors such as dietary lipids and organic pollutants. For example, we have evidence that endothelial caveolae play a role in uptake of persistent organic pollutants, an event associated with subsequent production of inflammatory mediators. Functional properties of caveolae can be modulated by nutrition, such as dietary lipids (e.g. fatty acids) and plant-derived polyphenols (e.g. flavonoids), which change activation of caveolae-associated signalling proteins. The following review will focus on caveolae providing a platform for pro-inflammatory signalling, and the role of caveolae in endothelial cell functional changes associated with environmental mediators such as nutrients and toxicants, which are known to modulate the pathology of vascular diseases. 相似文献
153.
A multiplex PCR approach to simultaneously genotype potato towards the resistance alleles Ry-f
sto
and Ns 总被引:1,自引:0,他引:1
Kamil Witek Danuta Strzelczyk-Żyta Jacek Hennig Waldemar Marczewski 《Molecular breeding : new strategies in plant improvement》2006,18(3):273-275
A simple and robust multiplex PCR approach was developed for detection of the alleles Ry-f
sto
and Ns conferring resistance of potato to Potato Virus Y (PVY) and Potato Virus S (PVS), respectively. Cleaved amplified polymorphic sequence (CAPS) markers GP122564 linked to Ry-f
sto
and SC811260 linked to Ns were amplified in one PCR reaction and identified after simultaneous digestion of the amplicons with restriction enzymes EcoRV and MboI. Effectiveness of this procedure for marker-assisted selection was confirmed in 55 potato cultivars. 相似文献
154.
155.
We investigated whether ranges in continental biota are nested. We propose a test for nested subset structure which can detect nestedness even if there are several sets of nested subsets as expected on a larger geographical scale. The test is based on a Monte Carlo simulation with a null model that considers spatial autocorrelation of the occurrences of a taxon. The number of cases in which the occurrences of a species form a subset of the occurrences of another species is used as test statistic. In a case study we show that the ranges of north-west European land snail species are significantly nested. The geographic centres of the sets of nested subsets correlate with glacial refuges. The differential immigration of taxa restricted to southern refuges during the glacials was probably an important mechanism resulting in the observed nestedness of the ranges of the north-west European land snail species. Some species which were more widespread during Pleistocene glacials contribute little to the nested subset pattern and are not nested among themselves. A comparison between groups of species differing in their dispersal abilities indicates that differences in the degree of nestedness are primarily due to differences in the variance of range sizes and not in dispersal abilities. We found a very weak correlation between dispersal ability and the rank of ranges in the sets of nested subsets indicating that nestedness might in part be caused by differential dispersal abilities. We assume that the graded variation of environmental parameters might be more important in generating the nestedness of ranges of north-west European land snail species than their differential dispersal abilities. 相似文献
156.
Arabidopsis MSI1 is required for epigenetic maintenance of reproductive development 总被引:13,自引:0,他引:13
Hennig L Taranto P Walser M Schönrock N Gruissem W 《Development (Cambridge, England)》2003,130(12):2555-2565
WD40 repeat proteins similar to yeast MSI1 are conserved in animals and plants, in which they participate in complexes involved in chromatin metabolism. Although MSI1-like proteins are well characterised biochemically, their function in the development of multicellular eukaryotes is not well understood. We constructed Arabidopsis plants in which the AtMSI1 protein level was altered. Strong ectopic expression of AtMSI1 produced no visible altered phenotype, but reduction of AtMSI1 dramatically affected development. The primary shoot apical meristem was unable to develop organs after the transition to flowering. Flowers that developed on floral shoots from axillary meristems experienced a progressive loss of floral morphology, including a reduction in size of the petals and stamens and the development of carpel-like sepals. Ovule development was disrupted in all flowers, resulting in complete female sterility. Molecular analysis of the mutant plants revealed that AtMSI1 is required to maintain the correct temporal and organ-specific expression of homeotic genes, including AGAMOUS and APETALA2. In contrast, FAS1 and FAS2, which together with AtMSI1 form the chromatin assembly complex CAF-1, are not required for repression of these genes. Therefore, AtMSI1 has specific functions in addition to CAF-1-mediated chromatin assembly. Efficient formation of heterochromatin, but not methylation of centromeric DNA repeats, depends on AtMSI1 presence demonstrating a key role of AtMSI1 in maintenance of chromatin structure. 相似文献
157.
Merroun M Hennig C Rossberg A Geipel G Reich T Selenska-Pobell S 《Biochemical Society transactions》2002,30(4):669-672
A combination of EXAFS, transmission electron microscopy and energy-dispersive X-ray was used to conduct a molecular and atomic analysis of the uranium complexes formed by Acidithiobacillus ferrooxidans. The results demonstrate that this bacterium accumulates uranium as phosphate compounds. We suggest that at toxic levels when the uranium enters the bacterial cells, A. ferrooxidans can detoxify and efflux this metal by a process in which its polyphosphate bodies are involved. 相似文献
158.
Chen C Hennig GE Whiteley HE Manautou JE 《Journal of biochemical and molecular toxicology》2002,16(5):227-234
Mice pretreated with the peroxisome proliferator clofibrate (CFB) are highly resistant to acetaminophen (APAP)-induced hepatotoxicity. The objective of the present study was to investigate whether the increase in hepatic catalase activity following CFB pretreatment plays a role in this hepatoprotection. An irreversible inhibitor, 3-amino-1,2,4-triazole (3-AT), was used to modulate catalase activity. Hepatic catalase activity in mice pretreated with CFB (500 mg/kg, i.p., for 10 days) was significantly inhibited by 3-AT (100 or 500 mg/kg, i.p.). In addition, the lower dose of 3-AT (100 mg/kg) had minimal effect on biliary and urinary excretion of APAP metabolites generated from a nontoxic dose, suggesting that APAP metabolism was not modulated by this dose of 3-AT. The mortality rate of corn-oil-pretreated mice challenged with APAP (800 mg/kg, p.o.) was significantly increased by 3-AT (100 mg/kg, i.p.) given 1 h before APAP. As expected, CFB pretreatment conferred full protection against APAP-induced hepatotoxicity. The same 3-AT treatment, however, did not abolish hepatoprotection in CFB-pretreated mice, despite the marked inhibition of hepatic catalase activity. In conclusion, these results indicate that elevated catalase activity in mice exposed to CFB does not appear to mediate the hepatoprotection, suggesting that other cellular defense mechanisms are involved. 相似文献
159.
160.
Marczewski W Hennig J Gebhardt C 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2002,105(4):564-567
The dominant allele Ns confers in potato resistance to Potato virus S (PVS). To identify the chromosomal location of Ns, we mapped the Ns-linked marker SCG17448 and the ISSR marker UBC811600 to linkage group VIII of the RFLP map of a population that did not segregate for Ns. The map position of the Ns locus on chromosome VIII was confirmed with the detection of linkage between Ns and three RFLP markers, GP126, GP189 and CP16, known to be located in a corresponding region on potato chromosome VIII. PCR-based assays were developed for these RFLP markers. The PCR primers specific for GP126 generated polymorphic products (STS marker). In the case of markers GP189 and CP16, informative polymorphism was revealed in the Ns population after digestion with the restriction enzymes HaeIII and HindIII, respectively. The genetic distance between Ns and the closest CP16 locus was 4.2 cM. 相似文献