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961.
962.
We characterized the proteomes of murine N2a cells following infection with three rabies virus (RV) strains, characterized by distinct virulence phenotypes (i.e., virulent BD06, fixed CVS-11, and attenuated SRV9 strains), and identified 35 changes to protein expression using two-dimensional gel electrophoresis in whole-cell lysates. The annotated functions of these proteins are involved in various cytoskeletal, signal transduction, stress response, and metabolic processes. Specifically, a-enolase, prx-4, vimentin, cytokine-induced apoptosis inhibitor 1 (CIAPIN1) and prx-6 were significantly up-regulated, whereas Trx like-1 and galectin-1 were down-regulated following infection of N2a cells with all three rabies virus strains. However, comparing expressions of all 35 proteins affected between BD06-, CVS-11-, and SRV9-infected cells, specific changes in expression were also observed. The up-regulation of vimentin, CIAPIN1, prx-4, and 14-3-3 theta/delta, and downregulation of NDPK-B and HSP-1 with CVS and SRV9 infection were ≥ 2 times greater than with BD06. Meanwhile, Zfp12 protein, splicing factor, and arginine/serine-rich 1 were unaltered in the cells infected with BD06 and CVS- 11, but were up-regulated in the group infected with SRV9. The proteomic alterations described here may suggest that these changes to protein expression correlate with the rabies virus' adaptability and virulence in N2a cells, and hence provides new clues as to the response of N2a host cells to rabies virus infections, and may also aid in uncovering new pathways in these cells that are involved in rabies infections. Further characterization of the functions of the affected proteins may contribute to our understanding of the mechanisms of RV infection and pathogenesis.  相似文献   
963.
964.
965.
对子莲(Nelumbo nucifera Gaertn.)新品种‘武植子莲1号’和‘武植子莲2号’与其他12个主栽子莲品种的莲子产量和品质性状进行分析,并通过隶属函数分析法对他们的营养品质性状进行综合评价。结果显示:不同子莲品种的产量和营养品质性状差异显著,同一品种在不同发育时期莲子的可溶性糖和淀粉含量等营养指标差异较大;鲜莲子的可溶性糖含量显著高于成熟莲子,而蛋白质和淀粉含量显著低于成熟莲子。与12个主栽子莲品种相比,‘武植子莲1号’在产量上较为突出,成熟莲子的淀粉含量达52.15%,是生产天然淀粉的优良品种;‘武植子莲2号’鲜莲子的直链淀粉和支链淀粉含量低,可溶性糖含量达23.43%,适合鲜食。隶属函数分析结果表明,‘武植子莲1号’和‘武植子莲2号’的综合营养品质较好,具有很高的应用价值。  相似文献   
966.
Cui  Kai-Cheng  Liu  Min  Ke  Gui-Hua  Zhang  Xing-Yuan  Mu  Bo  Zhou  Min  Hu  Yang  Wen  Ying-Qiang 《Plant Cell, Tissue and Organ Culture》2021,146(3):621-633

As one of the most economically important fruit crops in the world, the grapevine (Vitis vinifera) suffers significant yield losses from various pathogens including powdery mildew caused by Erysiphe necator. In contrast, several wild Chinese grapevines, including Vitis pseudoreticulata accession Baihe-35-1, are highly resistant to powdery mildew pathogens. Here, we identified a grapevine gene CSN5 (COP9 signalosome complex subunit 5), designated VvCSN5, that was differentially expressed between the resistant ‘Baihe-35-1’ and susceptible ‘Thompson Seedless’ during powdery mildew isolate Erysiphe necator NAFU1 infection. Moreover, transient silencing of VvCSN5 in ‘Thompson Seedless’ leaves enhanced resistance to En NAFU1. This resistance manifested in cell wall callose deposition at attempted infection sites and hypersensitive response-like cell death of penetrated epidermal cells. Several defense-related marker genes (VvPR1, VvPR3, VvPAD4, and VvRBOHD) had higher basal expression levels in VvCSN5-silenced leaves. In addition, we found the structure and activity of CSN5 promoters in ‘Thompson Seedless’ and ‘Baihe-35-1’ were different, which may have been behind their different resistances to powdery mildew infection. Taken together, these results implied that grapevine CSN5 plays an important role in the response to powdery mildew infection.

  相似文献   
967.
Much data implicate saturated fatty acids in deleterious processes associated with obesity, diabetes, and the metabolic syndrome. Many of these changes may be due to aberrant generation of bioactive lipids when saturated fatty acid availability to tissues is increased. On the other hand, studies are emerging that implicate the monounsaturated fatty acid oleate in protection from saturated fat mediated toxicity; however, the mechanisms are not well understood. Our data demonstrate a novel role for palmitate in increasing mRNA encoding DES1, which is the enzyme responsible for generating ceramide from its precursor dihydroceramide and thus controls synthesis of the bioactive lipid ceramide. Moreover, co-treatment with oleate prevented the increase in ceramide, and this occurred through attenuation of the increase in message and activity of DES1. Knockdown of DES1 also protected from palmitate-induced insulin resistance, and overexpression of this enzyme ameliorated the protective effect of oleate. Together, these findings provide insight into the mechanisms of oleate-mediated protection against metabolic disease and provide novel evidence for fatty acid-mediated regulation of a key enzyme of ceramide biosynthesis.  相似文献   
968.
肚倍是一种商品化的五倍子,富含鞣质、没食子酸等重要成分,具有重要的药用价值及工业用途。研究不同生长发育时期五倍子主要成分的含量变化,探索变化规律对肚倍更深入的研究具有长远意义。本文以湖北省竹山县溢水镇东川苗圃、文峰乡肖家垭、德胜镇王家湾生产的肚倍为样品,每隔10天采摘一次,称重并测定其主要成分的含量,直至虫瘿成熟爆裂。经测定,3个产地的肚倍含有丰富的鞣质(约70.0%)、游离没食子酸(约5.0%)、1,2,3,4,6-五-O-没食子酰-β-葡萄糖(β-PGG,约6.0%)、可溶性总糖(约8.2%)、氨基酸(约7.5%)等,在不同的生长期,这些主要成分的含量无大的差异,而且主要的几种重金属元素铁(Fe)、锌(Zn)、铜(Cu)、钡(Ba)、铅(Pb)和砷(As)在生长过程中也不会累积,不影响采摘时间。综合考虑肚倍的生长情况和经济价值,肚倍适宜在其个头最大,即体积基本不再增长且未爆裂、无霉烂时采摘。  相似文献   
969.

Background

Genome variability can have a profound influence on the virulence of pathogenic microbes. The availability of genome sequences for two strains of the AIDS-associated fungal pathogen Cryptococcus neoformans presented an opportunity to use comparative genome hybridization (CGH) to examine genome variability between strains of different mating type, molecular subtype, and ploidy.

Results

Initially, CGH was used to compare the approximately 100 kilobase MAT a and MATα mating-type regions in serotype A and D strains to establish the relationship between the Log2 ratios of hybridization signals and sequence identity. Subsequently, we compared the genomes of the environmental isolate NIH433 (MAT a) and the clinical isolate NIH12 (MATα) with a tiling array of the genome of the laboratory strain JEC21 derived from these strains. In this case, CGH identified putative recombination sites and the origins of specific segments of the JEC21 genome. Similarly, CGH analysis revealed marked variability in the genomes of strains representing the VNI, VNII, and VNB molecular subtypes of the A serotype, including disomy for chromosome 13 in two strains. Additionally, CGH identified differences in chromosome content between three strains with the hybrid AD serotype and revealed that chromosome 1 from the serotype A genome is preferentially retained in all three strains.

Conclusion

The genomes of serotypes A, D, and AD strains exhibit extensive variation that spans the range from small differences (such as regions of divergence, deletion, or amplification) to the unexpected disomy for chromosome 13 in haploid strains and preferential retention of specific chromosomes in naturally occurring diploids.  相似文献   
970.
Cynaroside is a flavonoid compound proved to possess antioxidant activity, but its protective effect on age‐related macular degeneration still remains unclear. In this study, the protective effects of cynaroside on oxidative stress and apoptosis in retinal pigment epithelial (RPE) cells induced by hydrogen peroxide (H2O2) were investigated. Results showed that cynaroside effectively attenuated the decrease of cell activity induced by H2O2. The total reactive oxygen species can be remitted by decreasing malondialdehyde level, as well as increasing glutathione level, and superoxide dismutase and catalase activities. In addition, Western blot analysis indicated that cynaroside protected ARPE‐19 cells from apoptosis through downregulation of caspase‐3 protein activation which was controlled by the upstream proteins Bcl‐2 and Bax. It was finally proved that cynaroside could enhance the antioxidant and antiapoptotic ability in ARPE‐19 cells by promoting the expression of p‐Akt.  相似文献   
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