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991.
Guoqiang Zhang Mingtao Fan Qian Lv Yahui Li Yanlin Liu Shuangfeng Zhang Hua Zhang 《Annals of microbiology》2013,63(2):477-485
The effects of stress shocks on the freeze-drying viability, malolactic activity and membrane fatty acid composition of the Oenococcus oeni SD-2a cells were studied. O. oeni SD-2a cells after 2 h of stress exposure exhibited better freeze-drying viability and malolactic fermentation ability. A decrease in unsaturated fatty acids/saturated fatty acids (UFA/SFA) ratio and in the C18:1 relative concentration, and an increase in cyclopropane fatty acids (CFA) content mainly due to the increase in C19cyc11 relative concentration were observed in all stress shocked cells. There was a significant negative correlation between C19cyc11 and C18:lcis11, C16:0 in all stress shocks. The freeze-drying viability exhibited a significant positive correlation with the levels of C19cyc11 in cold and acid shocks. The only significant positive correlation between the ability of O. oeni SD-2a to conduct malic acid degradation and membrane composition existed with C14:0 in ethanol shocks. In general, freeze-drying viabilities were maximum for cells with low UFA/SFA ratio and high CFA levels, and, consequently, with low membrane fluidity. Moreover, CFA formation played a major role in protecting stress shocked cells from lyophilization. However, changes observed in membrane fatty acid composition are not enough to explain the greater freeze-drying viability of cells shocked at 8% ethanol. Thus, other mechanisms could be responsible for this increase in the bacterial resistance to lyophilization. 相似文献
992.
Pei Ge Pengchao Hao Min Cao Guangfang Guo Dongwen Lv Saminathan Subburaj Xiaohui Li Xing Yan Jitian Xiao Wujun Ma Yueming Yan 《Proteomics》2013,13(20):3046-3058
As an abundant ROS, hydrogen peroxide (H2O2) plays pivotal roles in plant growth and development. In this work, we conducted for the first time an iTRAQ‐based quantitative proteomic analysis of wheat seedling growth under different exogenous H2O2 treatments. The growth of seedlings and roots was significantly restrained by increased H2O2 concentration stress. Malondialdehyde, soluble sugar, and proline contents as well as peroxidase activity increased with increasing H2O2 levels. A total of 3 425 proteins were identified by iTRAQ, of which 157 showed differential expression and 44 were newly identified H2O2‐responsive proteins. H2O2‐responsive proteins were mainly involved in stress/defense/detoxification, signal transduction, and carbohydrate metabolism. It is clear that up‐regulated expression of signal transduction and stress/defence/detoxification‐related proteins under H2O2 stress, such as plasma membrane intrinsic protein 1, fasciclin‐like arabinogalactan protein, and superoxide dismutase, could contribute to H2O2 tolerance of wheat seedlings. Increased gluconeogenesis (phosphoenol‐pyruvate carboxykinase) and decreased pyruvate kinase proteins are potentially related to the higher H2O2 tolerance of wheat seedlings. A metabolic pathway of wheat seedling growth under H2O2 stress is presented. 相似文献
993.
Shoujun Huang Zhao Zhang Chunxia Zhang Xiangdong Lv Xiudeng Zheng Zhenping Chen Liwei Sun Hailong Wang Yuanxiang Zhu Jing Zhang Shuyan Yang Yi Lu Qinmiao Sun Yi Tao Feng Liu Yun Zhao Dahua Chen 《PLoS biology》2013,11(11)
Hedgehog signaling plays conserved roles in controlling embryonic development; its dysregulation has been implicated in many human diseases including cancers. Hedgehog signaling has an unusual reception system consisting of two transmembrane proteins, Patched receptor and Smoothened signal transducer. Although activation of Smoothened and its downstream signal transduction have been intensively studied, less is known about how Patched receptor is regulated, and particularly how this regulation contributes to appropriate Hedgehog signal transduction. Here we identified a novel role of Smurf E3 ligase in regulating Hedgehog signaling by controlling Patched ubiquitination and turnover. Moreover, we showed that Smurf-mediated Patched ubiquitination depends on Smo activity in wing discs. Mechanistically, we found that Smo interacts with Smurf and promotes it to mediate Patched ubiquitination by targeting the K1261 site in Ptc. The further mathematic modeling analysis reveals that a bidirectional control of activation of Smo involving Smurf and Patched is important for signal-receiving cells to precisely interpret external signals, thereby maintaining Hedgehog signaling reliability. Finally, our data revealed an evolutionarily conserved role of Smurf proteins in controlling Hh signaling by targeting Ptc during development. 相似文献
994.
995.
Shifeng Cheng Erik van den Bergh Peng Zeng Xiao Zhong Jiajia Xu Xin Liu Johannes Hofberger Suzanne de Bruijn Amey S. Bhide Canan Kuelahoglu Chao Bian Jing Chen Guangyi Fan Kerstin Kaufmann Jocelyn C. Hall Annette Becker Andrea Br?utigam Andreas P.M. Weber Chengcheng Shi Zhijun Zheng Wujiao Li Mingju Lv Yimin Tao Junyi Wang Hongfeng Zou Zhiwu Quan Julian M. Hibberd Gengyun Zhang Xin-Guang Zhu Xun Xu M. Eric Schranz 《The Plant cell》2013,25(8):2813-2830
The Brassicaceae, including Arabidopsis thaliana and Brassica crops, is unmatched among plants in its wealth of genomic and functional molecular data and has long served as a model for understanding gene, genome, and trait evolution. However, genome information from a phylogenetic outgroup that is essential for inferring directionality of evolutionary change has been lacking. We therefore sequenced the genome of the spider flower (Tarenaya hassleriana) from the Brassicaceae sister family, the Cleomaceae. By comparative analysis of the two lineages, we show that genome evolution following ancient polyploidy and gene duplication events affect reproductively important traits. We found an ancient genome triplication in Tarenaya (Th-α) that is independent of the Brassicaceae-specific duplication (At-α) and nested Brassica (Br-α) triplication. To showcase the potential of sister lineage genome analysis, we investigated the state of floral developmental genes and show Brassica retains twice as many floral MADS (for MINICHROMOSOME MAINTENANCE1, AGAMOUS, DEFICIENS and SERUM RESPONSE FACTOR) genes as Tarenaya that likely contribute to morphological diversity in Brassica. We also performed synteny analysis of gene families that confer self-incompatibility in Brassicaceae and found that the critical SERINE RECEPTOR KINASE receptor gene is derived from a lineage-specific tandem duplication. The T. hassleriana genome will facilitate future research toward elucidating the evolutionary history of Brassicaceae genomes. 相似文献
996.
997.
Ren Yijing Lv Cheng Zhang Jing Zhang Beibei Yue Bei Luo Xiaoping Yu Zhilun Wang Hao Ren Junyu Wang Zhengtao Dou Wei 《Molecular and cellular biochemistry》2021,476(12):4387-4403
Molecular and Cellular Biochemistry - Colorectal cancer (CRC) is one of the most common human malignancies in the digestive tract with high mortality. Alantolactone (ATL), as a plant-derived... 相似文献
998.
999.
【目的】本试验测定了两个奶牛场健康乳汁和乳房炎乳汁中微生物菌群的变化,以揭示不同奶牛场之乳汁菌群的异同,评估其对乳汁代谢的影响是否相同。【方法】采用16S rRNA高通量测序技术,分别测定两个奶牛场6头健康奶牛和6头乳房炎奶牛乳汁中微生物16S rRNA V4区序列,并对菌群群落结构和多样性进行比较,分析场内及场间的乳汁菌群差异。【结果】四组乳汁样本共获得4013234条原始序列,经过滤后获得2887024条优化序列。Alpha多样性Chao指数、Ace指数、Shannon指数、Simpson指数差异均不显著(P0.05);Beta多样性四组样本均分别聚类;在场1和场2中,引起奶牛乳房炎的优势菌属分别是克雷伯氏菌属和埃希氏菌属;在2个奶牛场的健康乳汁中,场2的埃希氏菌属、葡萄球菌属的丰度显著高于场1;在2个奶牛场的乳房炎乳汁中,场2的埃希氏菌属、乳球菌属的丰度显著高于场1;2个奶牛场健康乳汁中的嗜冷菌总丰度分别为31.87%和38.72%;关联分析及功能预测分析表明,2个奶牛场健康乳汁与乳房炎乳汁优势物种之间的关系差异较大;场1无论是Level 1还是Level 2水平,均发现显著性差异的代谢通路,而场2均未发现显著性差异的代谢通路。【结论】本试验研究了两个奶牛场健康乳汁和乳房炎乳汁微生物菌群之间的异同,为两个奶牛场在乳房炎的预防工作以及原料奶在冷链运输过程中质量控制提供理论依据。 相似文献
1000.
Lijia Zhang Lifang Lv Nan Zheng Ruotong Li Rui Yang Tianyu Li Yingnan Li Yingqi Liu Hongwei Luo Xuelian Li Yuhong Zhou Hongli Shan Bing Bai Haihai Liang 《Journal of cellular physiology》2021,236(2):1094-1104
Sox4 participates in the progression of embryo development and regulation of apoptosis in tumors. However, the effect and mechanism of Sox4 in myocardial infarction (MI) remains unclear. Therefore, we aimed at examining the role and molecular mechanism of Sox4 in the process of cardiomyocytes apoptosis during MI. The expression of Sox4 were obviously increased both in MI mice and in neonatal mouse cardiomyocytes treated with H2O2. Overexpression of Sox4 promoted cardiomyocyte apoptosis with or without H2O2, whereas knocking down of Sox4 alleviated H2O2‐induced apoptosis in cardiomyocytes. Furthermore, silencing Sox4 by AAV‐9 carried short hairpin RNA targeting Sox4 (AAV‐9‐sh‐Sox4) markedly decreased cardiac infarct area, imprfoved cardiac dysfunction, and reversed apoptosis in MI mice. Mechanistically, there is a potential Sox4‐binding site in the promoter region of Bim, and forced expression of Sox4 significantly promoted Bim expression in cultured cardiomyocytes with or without H2O2, whereas knocking down of Sox4 inhibited the expression of Bim. Further studies showed that silencing Bim attenuated Sox4‐induced apoptosis in cardiomyocytes, indicating that Sox4 promoted cardiomyocytes apoptosis through regulation of Bim expression, which can be used as a potential therapeutic target for MI. 相似文献