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排序方式: 共有338条查询结果,搜索用时 171 毫秒
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Ikeda S Okubo T Takeda N Banba M Sasaki K Imaizumi-Anraku H Fujihara S Ohwaki Y Ohshima K Fukuta Y Eda S Mitsui H Hattori M Sato T Shinano T Minamisawa K 《Applied and environmental microbiology》2011,77(13):4399-4405
The effects of the Oryza sativa calcium/calmodulin-dependent protein kinase OsCCaMK genotype (dominant homozygous [D], heterozygous [H], recessive homozygous [R]) on rice root-associated bacteria, including endophytes and epiphytes, were examined by using a Tos17 rice mutant line under paddy and upland field conditions. Roots were sampled at the flowering stage and were subjected to clone library analyses. The relative abundance of Alphaproteobacteria was noticeably decreased in R plants under both paddy and upland conditions (0.8% and 3.0%, respectively) relative to those in D plants (10.3% and 17.4%, respectively). Population shifts of the Sphingomonadales and Rhizobiales were mainly responsible for this low abundance in R plants. The abundance of Anaerolineae (Chloroflexi) and Clostridia (Firmicutes) was increased in R plants under paddy conditions. The abundance of a subpopulation of Actinobacteria (Saccharothrix spp. and unclassified Actinosynnemataceae) was increased in R plants under upland conditions. Principal coordinate analysis revealed unidirectional community shifts in relation to OsCCaMK gene dosage under both conditions. In addition, shoot length, tiller number, and plant weight decreased as the OsCCaMK gene dosage decreased under upland conditions. These results suggest significant impacts of OsCCaMK on both the diversity of root-associated bacteria and rice plant growth under both paddy and upland field conditions. 相似文献
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Eri Asano Hitoki Hasegawa Toshinori Hyodo Satoko Ito Masao Maeda Dan Chen 《Cell cycle (Georgetown, Tex.)》2014,13(17):2744-2751
The centralspindlin complex, which is composed of MKLP1 and MgcRacGAP, is one of the crucial factors involved in cytokinesis initiation. Centralspindlin is localized at the middle of the central spindle during anaphase and then concentrates at the midbody to control abscission. A number of proteins that associate with centralspindlin have been identified. These associating factors regulate furrowing and abscission in coordination with centralspindlin. A recent study identified a novel centralspindlin partner, called Nessun Dorma, which is essential for germ cell cytokinesis in Drosophila melanogaster. SHCBP1 is a human ortholog of Nessun Dorma that associates with human centralspindlin. In this report, we analyzed the interaction of SHCBP1 with centralspindlin in detail and determined the regions that are required for the interaction. In addition, we demonstrate that the central region is necessary for the SHCBP1 dimerization. Both MgcRacGAP and MKLP1 are degraded once cells exit mitosis. Similarly, endogenous and exogenous SHCBP1 were degraded with mitosis progression. Interestingly, SHCBP1 expression was significantly reduced in the absence of centralspindlin, whereas centralspindlin expression was not affected by SHCBP1 knockdown. Finally, we demonstrate that SHCBP1 depletion promotes midbody structure disruption and inhibits abscission, a final stage of cytokinesis. Our study gives novel insight into the role of SHCBP in cytokinesis completion. 相似文献
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217.
Shinya Fukumoto Kiwamu Hanazono Dah-Renn Fu Yoshifumi Endo Tsuyoshi Kadosawa Hidetomo Iwano Tsuyoshi Uchide 《Biochemical and biophysical research communications》2013
L-type amino acid transporter 1 (LAT1), an isoform of amino acid transport system L, transports branched or aromatic amino acids essential for fundamental cellular activities such as cellular growth, proliferation and maintenance. This amino acid transporter recently has received attention because of its preferential and up-regulated expression in a variety of human tumors in contrast to its limited distribution and low-level expression in normal tissues. In this study, we explored the feasibility of using LAT1 inhibitor as a new therapeutic agent for human malignant melanomas (MM) using canine spontaneous MM as a model for human MM. A comparative study of LAT expression was performed in 48 normal tissues, 25 MM tissues and five cell lines established from MM. The study observed LAT1 mRNA levels from MM tissues and cell lines that were significantly (P < 0.01) higher than in normal tissues. Additionally, MM with distant metastasis showed a higher expression than those without distant metastasis. Functional analysis of LAT1 was performed on one of the five cell lines, CMeC-1. [3H]l-Leucine uptake and cellular growth activities in CMeC-1 were inhibited in a dose-dependent manner by selective LAT1 inhibitors (2-amino-2-norbornane-carboxylic acid, BCH and melphalan, LPM). Inhibitory growth activities of various conventional anti-cancer drugs, including carboplatin, cyclophosphamide, dacarbazine, doxorubicin, mitoxantrone, nimustine, vinblastine and vincristine, were significantly (P < 0.05) enhanced by combination use with BCH or LPM. These findings suggest that LAT1 could be a new therapeutic target for MM. 相似文献
218.
Changes in stable nitrogen and carbon isotope ratios of plants and soil across a boreal forest fire chronosequence 总被引:1,自引:0,他引:1
Fujio Hyodo Soichiro Kusaka David A. Wardle Marie-Charlotte Nilsson 《Plant and Soil》2013,364(1-2):315-323
Background and Aim
Nitrogen (N) and carbon (C) isotopic signatures (δ15N and δ13C) serve as powerful tools for understanding temporal changes in ecosystem processes, but how these signatures change across boreal forest chronosequences is poorly understood.Methods
The δ15N, δ13C, and C/N ratio of foliage of eight dominant plant species, including trees, understory shrubs, and a moss, as well as humus, were examined across a 361 years fire-driven chronosequence in boreal forest in northern Sweden.Results
The δ13C and C/N ratio of plants and humus increased along the chronosequence, suggesting increasing plant stress through N limitation. Despite increasing biological N fixation by cyanobacteria associated with feather mosses, δ15N showed an overall decline, and δ15N of the feather moss and associated vascular plants diverged over time from that of atmospheric N2.Conclusions
Across this chronosequence the N fixed by cyanobacteria is unlikely to be used by mosses and vascular plants without first undergoing mineralization and mycorrhizal transport, which would cause a change in δ15N signature due to isotopic fractionation. The decreasing trend of δ15N suggests that as the chronosequence proceeds, the plants may become more dependent on N transferred from mycorrhizal fungi or from N deposition. 相似文献219.
Kenji Tagai Maiko Ono Manabu Kubota Soichiro Kitamura Keisuke Takahata Chie Seki Yuhei Takado Hitoshi Shinotoh Yasunori Sano Yasuharu Yamamoto Kiwamu Matsuoka Hiroyuki Takuwa Masafumi Shimojo Manami Takahashi Kazunori Kawamura Tatsuya Kikuchi Maki Okada Haruhiko Akiyama Hitoshi Shimada 《Neuron》2021,109(1):42-58.e8
220.
Nakasone C Yamamoto N Nakamatsu M Kinjo T Miyagi K Uezu K Nakamura K Higa F Ishikawa H O'brien RL Ikuta K Kaku M Fujita J Kawakami K 《Microbes and infection / Institut Pasteur》2007,9(3):251-258
The present study was designed to elucidate the role of Vgamma4(+) gammadelta T cells, a major subset of pulmonary gammadelta T cells, in host defense against infection with Streptococcus pneumoniae. The proportion and number of whole gammadelta T cells, identified as CD3(+) and TCR-delta(+) cells, and Vgamma4(+) gammadelta T cells, identified as CD3(+) and TCR-Vgamma4(+) cells, increased in the lungs at 3, 6 and 12h post-infection. Survival of infected mice and lung bacterial clearance were severely impaired in TCR-Vgamma4(-/-) mice compared with control wild-type (WT) mice. The impaired host protection in TCR-Vgamma4(-/-) mice correlated well with attenuated recruitment of neutrophils in lungs. MIP-2 and TNF-alpha synthesis in the infected tissues was significantly reduced in TCR-Vgamma4(-/-) mice compared with WT mice. Similar results were noted in the synthesis of TNF-alpha, but not clearly of MIP-2, by lung leukocytes stimulated with live bacteria. Our results demonstrate that Vgamma4(+) gammadelta T cells play an important role in the neutrophil-mediated host defense against S. pneumoniae infection by promoting the synthesis of TNF-alpha and possibly of MIP-2 in the lungs. 相似文献