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111.
The protein p53 plays a crucial role in the regulation of cellular responses to diverse stresses. Thus, a major priority in cell biology is to define the mechanisms that regulate p53 activity in response to stresses or maintain it at basal levels under normal conditions. Moreover, further investigation is required to establish whether RNA participates in regulating p53's interaction with other proteins. Here, by conducting systematic experiments, we discovered a p53 interactor—hnRNPC—that directly binds to p53, destabilizes it, and prevents its activation under normal conditions. Upon doxorubicin treatment, the lncRNA SNHG1 is retained in the nucleus through its binding with nucleolin and it competes with p53 for hnRNPC binding, which upregulates p53 levels and promotes p53‐dependent apoptosis by impairing hnRNPC regulation of p53 activity. Our results indicate that a balance between lncRNA SNHG1 and hnRNPC regulates p53 activity and p53‐dependent apoptosis upon doxorubicin treatment, and further indicate that a change in lncRNA subcellular localization under specific circumstances is biologically significant.  相似文献   
112.
摘要:【目的】:探讨海洋芽孢杆菌(Bacillus marinus)B-9987菌株的代谢产物BMME-1,对植物病原真菌茄链格孢菌的抑菌作用机理。【方法】分别使用分光光法、气相色谱-质谱GC-MS联用技术、红外光谱法等,检测了BMME-1处理病原真菌后,菌体渗透性、细胞壁及细胞膜成份的变化。【结果】BMME-1对茄链格孢菌的抑菌中浓度(MIC50)为6.2 mg/L,最小杀菌浓度(MFC)为50 mg/L,在MIC50浓度或高于此浓度处理靶标菌,将导致菌体蛋白质、核酸等大分子物质的外流;处理菌株葡聚糖结  相似文献   
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南京城市公园绿地不同植被类型土壤呼吸的变化   总被引:9,自引:0,他引:9  
子2007年10月-2008年9月,利用Li-6400便携式光合作用仪配合土壤呼吸气室对南京中山植物园内草坪、疏林和近自然林3种植被类型的土壤呼吸速率的季节变化及其影响因子进行了测定.结果表明:不同植被类型土壤呼吸速率具有明显的季节变化,夏季(8月)较高,近自然林、疏林和草坪类型分别为3.28、4.07和7.58 μmol·m~(-2)·s~(-1),冬季(12月)最低,近自然林、疏林和草坪类型分别为0.82、0.99和1.42 μmol·m~(-2)·s~(-1);不同植被类型的年均土壤呼吸速率有显著差异(P<0.05),平均土壤呼吸速率大小排序为草坪>疏林>近自然林;不同植被类型的土壤呼吸速率与土壤温度呈显著性指数相关关系,与土壤含水率无显著相关关系;Q_(10)值均随着土层深度的增加而增加;不同植被类型的Q_(10)值存在一定程度的差异,近自然林类型的Q_(10)值大于草坪和疏林类型的Q_(10)值.研究表明,城市如果大量发展草坪可能增加土壤CO_2的排放.
Abstract:
By using Li-6400 portable photosynthetic apparatus connected to soil chamber,the soil respiration rate under three vegetation types(lawn,open woodland,and close-to-nature forest)in Nanjing Zhongshan Botanical Garden was measured from October 2007 to September 2008,with related affecting factors analyzed.The soil respiration rate had obvious seasonal fluctuation,being the highest in summer(August)and the lowest in winter(December).For the close-to-nature forest,open woodland,and lawn,their soil respiration rate in summer was 3.28,4.07,and 7.58μmol·m~(-2)·s~(-1),and that in winter was 0.82,0.99,and 1.42μmol·m~(-2)·s~(-1),respectively.The annual mean soil respiration rate differed significantly with vegetation type(P<0.05),which was in order of close-to-nature forest<open woodland<lawn.The soil respiration rate had significant exponential correlation with soil temperature,but no correlation with soil moisture.The Q_(10) value increased with increasing soil depth,and was larger in close-tonature forest than in open woodland and lawn.Our results indicated that the rapid development of lawn in urban green space could increase the urban soil CO_2 emission.  相似文献   
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水分胁迫降低了甘薯叶肉细胞的光合能力。在有解偶联剂存在时,水分胁迫对叶肉细胞的光合电子传递没有影响,但在无解偶联剂存在下,水分胁迫促进了甘薯叶肉细胞的光合电子传递,表现出明显的解偶联效应。水分胁迫伤害了甘薯叶绿体偶联因子结构,使ATP合成受阻,叶肉细胞的光合滞后期加长。  相似文献   
118.
The relationship between vegetation and soil erosion deserves attention due to its scientific importance and practical applications. A great deal of information is available about the mechanisms and benefits of vegetation in the control of soil erosion, but the effects of soil erosion on vegetation development and succession is poorly documented. Research shows that soil erosion is the most important driving force for the degradation of upland and mountain ecosystems. Soil erosion interferes with the process of plant community development and vegetation succession, commencing with seed formation and impacting throughout the whole growth phase and affecting seed availability, dispersal, germination and establishment, plant community structure and spatial distribution. There have been almost no studies on the effects of soil erosion on seed development and availability, of surface flows on seed movement and redistribution, and their influences on soil seed bank and on vegetation establishment and distribution. However, these effects may be the main cause of low vegetation cover in regions of high soil erosion activity and these issues need to be investigated. Moreover, soil erosion is not only a negative influence on vegetation succession and restoration, but also a driving force of plant adaptation and evolution. Consequently, we need to study the effects of soil erosion on ecological processes and on development and regulation of vegetation succession from the points of view of pedology and vegetation, plant and seed ecology, and to establish an integrated theory and technology for deriving practical solutions to soil erosion problems.  相似文献   
119.
研究人二倍体细胞甲型肝炎灭活疫苗的纯化方法。 经人二倍体细胞培养的病毒液经澄清、浓缩后制成粗制疫苗,采用Sephacryl S 400、DEAE Sepharose FF、Sephadex G 10等柱层析手段进行纯化。试验证明甲型肝炎病毒粗制疫苗经以上3种层析柱纯化后,抗原组分单一,收率达到85%,杂蛋白去除率达85%以上,蛋白总含量、牛血清残留量各项指标符合中国药典要求,适用于大规模生产。  相似文献   
120.
Animal cloning can be achieved by somatic cell nuclear transfer(SCNT), but the resulting live birth rate is relatively low. We previously improved the efficiency of bovine SCNT by exogenous melatonin treatment or by overexpression of lysine-specific demethylase 4D(KDM4D) and 4E(KDM4E). In this study, we revealed abundant alternative splicing(AS) transitions during fertilization and embryonic genome activation, and demonstrated abnormal AS in bovine SCNT embryos compared with in vitro fertilized ...  相似文献   
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