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161.
Sheath blight (ShB) severely threatens rice cultivation and production; however, the molecular mechanism of rice defence against ShB remains unclear. Screening of transposon Ds insertion mutants identified that Calcineurin B-like protein-interacting protein kinase 31 (CIPK31) mutants were more susceptible to ShB, while CIPK31 overexpressors (OX) were less susceptible. Sequence analysis indicated two haplotypes of CIPK31: Hap_1, with significantly higher CIPK31 expression, was less sensitive to ShB than the Hap_2 lines. Further analyses showed that the NAF domain of CIPK31 interacted with the EF-hand motif of respiratory burst oxidase homologue (RBOHA) to inhibit RBOHA-induced H2O2 production, and RBOHA RNAi plants were more susceptible to ShB. These data suggested that the CIPK31-mediated increase in resistance is not associated with RBOHA. Interestingly, the study also found that CIPK31 interacted with catalase C (CatC); cipk31 mutants accumulated less H2O2 while CIPK31 OX accumulated more H2O2 compared to the wild-type control. Further analysis showed the interaction of the catalase domain of CatC with the NAF domain of CIPK31 by which CIPK31 inhibits CatC activity to accumulate more H2O2.  相似文献   
162.
Global food security is one of the utmost essential challenges in the 21st century in providing enough food for the growing population while coping with the already stressed environment. High temperature (HT) is one of the main factors affecting plant growth, development and reproduction and causes male sterility in plants. In male reproductive tissues, metabolic changes induced by HT involve carbohydrates, lipids, hormones, epigenetics and reactive oxygen species, leading to male sterility and ultimately reducing yield. Understanding the mechanism and genes involved in these pathways during the HT stress response will provide a new path to improve crops by using molecular breeding and biotechnological approaches. Moreover, this review provides insight into male sterility and integrates this with suggested strategies to enhance crop tolerance under HT stress conditions at the reproductive stage.  相似文献   
163.
Nonalcoholic fatty liver disease (NAFLD) is a strong stimulant of cardiovascular diseases, affecting one-quarter of the world's population. TBC1 domain family member 25 (TBC1D25) regulates the development of myocardial hypertrophy and cerebral ischemia–reperfusion injury; however, its effect on NAFLD/nonalcoholic steatohepatitis (NASH) has not been reported. In this study, we demonstrated that TBC1D25 expression is upregulated in NASH. TBC1D25 deficiency aggravated hepatic steatosis, inflammation, and fibrosis in NASH. In vitro tests revealed that TBC1D25 overexpression restrained NASH responses. Subsequent mechanistic validation experiments demonstrated that TBC1D25 interfered with NASH progression by inhibiting abnormal lipid accumulation and inflammation. TBC1D25 deficiency significantly promoted NASH occurrence and development. Therefore, TBC1D25 may potentially be used as a clinical therapeutic target for NASH treatment.  相似文献   
164.
165.
A number of serious hereditary disorders are now known to be associated with defective expression of collagen genes, and these findings have underscored the important and varied roles that the collagen family of genes must play during normal mammalian development. Although the activities of genes encoding the quantitatively major types of collagen are fairly well characterized, functions of the many minor types of collagen remain a matter of speculation. As a first step toward a functional analysis of type XI collagen, a member of this class of poorly understand minor collagen proteins which is expressed primarily in hyaline cartilage, we have used human probes for the gene encoding the protein's 2-subunit (COL11A2) to isolate and map homologous murine DNA sequences. Our results demonstrate that Col11a-2 is embedded within the major histocompatibility complex (MHC), within 8.4 kb of the class II pseudogene locus, Pb, and confirm that human and murine 2(XI) collagen genes are located in very similar genomic environments. The conserved location of these genes raises the possibility that type XI collagen genes may contribute to one or more of the diverse hereditary disorders known to be linked to the MHC in mouse and human.  相似文献   
166.
本研究旨在建立一种简便、快捷、可直观检测小反刍兽疫病毒(peste des petits ruminants virus,PPRV)抗体的检测方法。将pET-32a-N重组质粒转化至大肠杆菌(Escherichia coli) Rosetta(DE3)感受态细胞中进行诱导表达,以纯化的PPRVN蛋白免疫8周龄BALB/c小鼠,取其脾细胞与SP2/0骨髓瘤细胞进行融合,间接酶联免疫吸附试验(enzyme-linked immunosorbent assays, ELISA)筛选及亚克隆,获得了抗PPRV N蛋白的单克隆抗体。将PPRV N蛋白分别作为金标抗原及检测线(T线)包被抗原、单克隆抗体作为质控线(C线)包被抗体,组装成检测PPRVN蛋白抗体的胶体金免疫层析试纸条。结果显示:成功获得1株能稳定分泌抗N蛋白抗体的杂交瘤细胞株,命名为1F1;间接ELISA检测1F1腹水效价为1:128000;亚类鉴定结果为IgG1,轻链为kappa链。Westernblotting结果显示,1F1能与PPRV N蛋白特异性结合;间接免疫荧光(indirect immunofluorescent ass...  相似文献   
167.
儿童最大有氧活动能力的发展特征   总被引:4,自引:1,他引:3  
本文报告了我国463名10-19岁儿童青少年的最大有氧活动能力的发展特征。在青春早期,男女童的最大吸氧量绝对值均随年龄增长而增加,男童由1.75升/分增至3.10升/分,女童由1.44升/分增至2.07升/分,女童增长较少;以后女童即稳定于这一水平,男童仍略有增长。按身高及按最大心率计标的相对值与其有相似的特征。按体重和瘦体重计算的相对值,在男女童都未见随年龄增长的规律。男童VO2max绝对值及各  相似文献   
168.
细胞腊脂流动性在不同类属细胞存在着差异,其差异的程度取决于细胞的生理和生化特性。正常淋巴细胞、肺腺癌、肺鳞癌细胞以及结核细胞膜脂流动发生 分别为2.517±0.267、22.557±3.771,32.875±9.709和4.026±0.722。细胞分裂动力学与膜脂质流动性有关系。细胞分裂及其程度是膜脂质流动性差异的物质基础,同时并受细胞膜脂质的组成,脂蛋白生化以及外界因素的pH、Ca^2+等影响,  相似文献   
169.
国家公园是我国推进生态文明建设的重大制度创新,如何科学地对国家公园进行类型划分及空间识别,是国家公园布局和建设中的基础性工作,既有必要性也有紧迫性。本研究以中国国情为基础,参考国际经验,将国家公园划分为荒野导向型、生态优先型、游憩导向型与遗产导向型,构建了一个比较完整的国家公园分类体系。并以自然和人文多样化程度较高的云南为案例,以“双评价”为基础建立了一套指标体系和区划规则,利用人工神经网络建立土地利用演化学习算法,利用融入自适应惯性机制的元胞自动机展开时空模拟,对云南全域进行高分辨率不同类型国家公园的空间辨识,并通过收缩-膨胀原理对识别区域进行比较、修正和优化,进而提出未来云南国家公园布局的综合方案。结果表明: 云南省国家公园主要集中在三江地区与横断山区、滇西以及西南部地区,这3类地区可作为未来国家公园区划与分类保护的重点。本研究所建立的国家公园类型划分和空间识别的一般性可推广的研究范式和工作流程可作为全国应用的参考。  相似文献   
170.
沙面结皮形成与微环境变化   总被引:31,自引:0,他引:31  
研究结果表明沙坡头地区的大气年降尘(d相似文献   
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