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991.
Yu‐Jiao Jia Dan‐Dan Cheng Wei‐Bin Wang Hui‐Yuan Gao Ai‐Xin Liu Xin‐Min Li Qing‐Wei Meng 《Physiologia plantarum》2010,138(2):164-175
The purpose of this study was to explore the mechanisms by which Alternaria alternata damages tobacco (Nicotiana tabacum) leaves. Treatment with A. alternata metabolic products enhanced senescence in leaves of different ages, as indicated by the significant decrease in chlorophyll, soluble protein, photosynthetic O2 evolution and catalase (CAT, EC 1.11.1.6) activity as well as an increase in H2O2 content. The induction of senescence by A. alternata metabolic products increased as the age of the leaves increased. A. alternata metabolic products greatly influenced the behavior of photosystem II (PSII) in the leaves: oxygen evolving complex (OEC) activity and electron transport from primary quinone electron acceptor of PS II (QA) to secondary quinone electron acceptor of PS II (QB) were both significantly inhibited. This inhibition also became more pronounced in older leaves. In vitro experiments revealed that, without the influence of natural senescence, the A. alternata metabolic products directly inhibited the activity of a commercial CAT solution and inhibited photosynthetic O2 evolution, which resulted in excess PSII excitation pressure and an overaccumulation of H2O2 in leaf segments. These results suggest that the significant declines in photosynthesis and CAT activity induced by the metabolic products of A. alternata were important contributors to the overaccumulation of reactive oxygen species (ROS), which accelerated senescence in tobacco leaves. The fact that the enhancement of senescence was getting more pronounced with the age of tobacco leaves might be related to the fact that older leaves already had higher H2O2 levels and less antioxidant activity as reflected in lower CAT activity. 相似文献
992.
993.
H. F. Peng X. H. Chen Y. P. Lu Y. F. Peng B. H. Wan N. D. Chen B. Wu S. P. Xin G. Q. Zhang 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2010,120(5):1013-1020
The thermo-sensitive genic male sterility (TGMS) lines play a crucial role in two-line hybrid rice production. For a practical
TGMS line, the stability of male sterility is one of the most important technical indicators. In this study, XianS, a spontaneous
mutant with stable male sterility from an indica rice cultivar Xianhuangzhan, was classified as a non-pollen type TGMS line. The critical non-pollen sterility point temperature
of XianS was determined as 27°C. Genetic analysis demonstrated that the non-pollen sterility in XianS was controlled by a
single recessive gene. Using SSR markers and bulked segregant analysis, the TGMS gene in XianS was fine mapped to a 183 kb
interval between RMAN81 and RMX21 on chromosome 2. Two markers, 4039-1 and RMX14 completely cosegregated with this gene. Allelism
test indicated that the non-pollen phenotype in seven non-pollen type TGMS lines from different sources, XianS, AnnongS-1,
Q523S, Q524S, N28S, G421S, and Q527S is caused by the same TGMS gene. Although the location of TGMS gene in XianS is close
to the gene OsNAC6, a previously identified candidate gene of tms5 in AnnongS-1, the sequence of OsNAC6 and its promoter region was identical in TGMS line XianS, AnnongS-1, and wild-type Xianhuangzhan. These results suggest that
the non-pollen type TGMS trait probably be controlled by the same TGMS gene in different TGMS rice lines, but its real candidate
gene still need to be further studied and identified. 相似文献
994.
Mingming Xin Yu Wang Yingyin Yao Chaojie Xie Huiru Peng Zhongfu Ni Qixin Sun 《BMC plant biology》2010,10(1):123
Background
MicroRNAs (miRNAs) are a class of small non-coding regulatory RNAs that regulate gene expression by guiding target mRNA cleavage or translational inhibition. MiRNAs can have large-scale regulatory effects on development and stress response in plants. 相似文献995.
Jianhuang Wu Mingqiang Wei Yonghong Li Xin Ma Fucang Jia Qingmao Hu 《Biomedical engineering online》2010,9(1):75
Background
The effective geometric modeling of vascular structures is crucial for diagnosis, therapy planning and medical education. These applications require good balance with respect to surface smoothness, surface accuracy, triangle quality and surface size. 相似文献996.
Frédéric-Antoine Dauchy Sébastien Dégrange Alain Charron Michel Dupon Yi Xin Cécile Bébéar Jeanne Maugein 《BMC microbiology》2010,10(1):93
Background
Mycobacterium intracellulare, a species of the Mycobacterium avium complex, may be the cause of severe lung, lymphatic node, skin and bone/joint infections, as well as bacteriemia. The goal of this work was to identify Mycobacterial Interspersed Repetitive Unit-Variable Number Tandem Repeat (MIRU-VNTR) markers and to study their variability in a collection of isolates of M. intracellulare collected in humans. We studied 61 isolates collected in humans between 2001 and 2008, as well as the reference strain, M. intracellulare ATCC 13950. 相似文献997.
Background
Intracellular bacterial pathogens depend on acquisition of iron for their success as pathogens. The host cell requires iron as an essential component for cellular functions that include innate immune defense mechanisms. The transferrin receptor TfR1 plays an important part for delivering iron to the host cell during infection. Its expression can be modulated by infection, but its essentiality for bacterial intracellular survival has not been directly investigated. 相似文献998.
Sebastian Dolff Daniel Quandt Benjamin Wilde Thorsten Feldkamp Fan Hua Xin Cai Christof Specker Andreas Kribben Cees GM Kallenberg Oliver Witzke 《Arthritis research & therapy》2010,12(4):R150
Introduction
There is growing evidence that interleukin 17 (IL-17) producing T cells are involved in the pathogenesis of systemic lupus erythematosus (SLE). Previous studies showed that increased percentages of T-cell subsets expressing the costimulatory molecules CD80 and CD134 are associated with disease activity and renal involvement in SLE. The aim of this study was to investigate the distribution and phenotypical characteristics of IL-17 producing T-cells in SLE, in particular in patients with lupus nephritis, with emphasis on the expression of CD80 and CD134. 相似文献999.
1000.
PHD finger8(PHF8)蛋白是最新发现的一种带有PHD结构域和Jmjc结构域的蛋白。现有研究表明其可能在基因转录、组蛋白去甲基化等方面发挥重要作用。为研究其功能,本研究构建原核表达载体pET41b-PHF8(aa886-936),在大肠杆菌Escherichia coli BL21中诱导表达带有GST标签的PHF8(aa886-936)亲水片段融合蛋白,并纯化该片段作为抗原免疫家兔,再以CNBr活化Sepharose4B微珠纯化抗血清制备PHF8特异性多克隆抗体。Western blotting以及免疫荧光检测表明该抗体具有很好的特异性,同时免疫荧光染色的结果也表明PHF8蛋白定位于细胞核。 相似文献