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Youli Zhang Dawei Wang Meiting Zhang Hong Wei Ying Lu Yaocheng Sun Meng Zhou Shuming Gu Wen Feng Huizhi Wang Jian Zeng Aihua Gong Min Xu 《Experimental cell research》2018,362(1):43-50
Protein arginine methyltransferase 1 (PRMT1) is up-regulated and promotes migration, invasion and proliferation in wide range of cancers. However, we for the first time identify that PRMT1 promotes migration and invasion and inhibits proliferation in gastric cancer cells, a phenomenon called “migration-proliferation dichotomy”. First, we find that PRMT1 overexpression promotes migration and invasion and inhibits proliferation, whereas PRMT1 knockdown reverses the above abilities. Next, PRMT1 reduces the expression of epithelial marker E-cadherin and increases the expression of mesenchymal markers including N-cadherin, Vimentin, snail and β-catenin in gastric cancer cells. Furthermore, our studies show that PRMT1 silencing promotes the phosphorylation of LATS1, and then induces YAP phosphorylation, while overexpression of PRMT1 down-regulates the phosphorylation of LATS1 and YAP, indicating that PRMT1 inhibits EMT probably via Hippo signaling. Collectively, the present study reveals important roles of PRMT1 in progression of gastric cancer. Given the dual functions of PRMT1, it is as a potential drug target of gastric cancer with extreme caution. 相似文献
123.
Li, Aihua, and Eugene E. Nattie. Focal centralchemoreceptor sensitivity in the RTN studied with aCO2 diffusion pipette in vivo.J. Appl. Physiol. 83(2): 420-428, 1997.We describe and use a CO2diffusion pipette to produce a quickly reversible focal acidosis in theretrotrapezoid nucleus region of the rat brain stem. No tissueinjection is made. Instead, artificial cerebrospinal fluid (aCSF)equilibrated with CO2 circulateswithin the micropipette, providing a source for continuedCO2 diffusion into the tissue fromthe pipette tip. Tissue pH electrodes show the acidosis is limited to500 µm from the tip. In controls (aCSF equilibrated with air), 1-minpipette perfusions increased tissue pH slightly and decreased phrenicnerve amplitude. In moderate- andhigh-CO2 groups (aCSF equilibratedwith 50 or 100% CO2), 1-minperfusions significantly decreased tissue pH and increased phrenicnerve amplitude in a dose-dependent manner. The responses developed andreversed within minutes. Compared with our prior use of medullary acetazolamide injections to produce a focal acidosis, in this approachthe acidosis 1) arises and reversesquickly and 2) its intensity can bevaried. This allows study of sensitivity and mechanism. We concludefrom this initial experiment that retrotrapezoid nucleus regionchemoreceptors operate within the normal physiological range ofCO2-induced tissue pH changes. 相似文献
124.
Xiaorong Liu Yongwei Qin Aihua Dai Yu Zhang Huaqing Xue Haidan Ni Lijian Han Liang Zhu Debin Yuan Tao Tao Maohong Cao 《Cellular and molecular neurobiology》2016,36(5):777-788
Initial exposure of macrophages to LPS induces hyporesponsiveness to a second challenge with LPS, a phenomenon termed LPS tolerance. Smad4 plays important roles in the induction of LPS tolerance. However, the function of Smad4 in microglia remains unknown. Here we show that expression of Smad4 was highly up-regulated in LPS-tolerized mouse cerebral cortex. Smad4 was mostly colocalized with microglia, rarely with neurons. Using a microglia cell line, BV2, we find that LPS activates endogenous Smad4, inducing its migration into the nucleus and increasing its expression. Smad4 significantly suppressed TLR-triggered production of proinflammatory cytokines (IL-6), increased anti-inflammatory cytokine in LPS-tolerized microglia. Moreover, IL-6 concentrations in culture supernatants after second LPS challenge are higher in SMAD4 small interfering RNA (siRNA) BV2 cells than control siRNA BV2 cells, indicating failure to induce tolerance in absence of Smad4 signaling. In our study, we conclude that both in vivo and in vitro, Smad4 signaling is required for maximal induction of endotoxin tolerance. 相似文献
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Jiang P Liu Y Yin X Yuan F Nie Y Luo M Aihua Z Liyin D Ding M Deng H 《Biochemical and biophysical research communications》2006,339(2):526-532
Recombinant viral vectors are useful tools for AIDS vaccine development. However, expression of HIV-1 envelope genes using viral vectors has not been successful in the induction of potent neutralizing antibodies in vivo. We took advantage of the strong immunogenicity of vesicular stomatitis virus (VSV)-based vector and expressed HIV-1 HXB2 gp120 gene in the recombinant VSV. Our results showed that HIV-1 gp120 protein expressed by the recombinant VSV retained the native conformation of the protein to some degree and was recognized by two well-characterized broad anti-HIV-1 neutralizing monoclonal antibodies b12, 2G12. We further showed that only one time intranasal immunization with the recombinant VSV led to production of anti-HIV-1 anti-sera in mice. In addition, we found that the anti-sera had the ability to neutralize not only HXB2 envelope-pseudotyped HIV-1 viruses but also HIV-1 pseudotyped viruses with JRFL envelopes. These results suggest that HIV-1 gp120 expressed by the recombinant VSV, in combination with the route of intranasal administration, is an effective strategy to evaluate the immunogenicity of HIV-1 envelope protein and its variants in mice. 相似文献
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Class II polypeptide release factor (eRF3), a ribosome and eRF1-dependent GTPase, is an important factor, which acts cooperatively with eRF1 to promote hydrolysis of the ester bond linking the polypeptide chain with the peptidyl site tRNA in process of termination of protein synthesis. We prepared antibodies against eRF3 of Euplotes octocarinatus, and performed localization studies by immunoelectron microscopy in the ciliate. Our results indicate that eRF3 is present both in the cytoplasm and the two types of nuclei of this organism. The functions of eRF3 in these nuclei were analyzed by RNA interference methods. The nuclei loose their shape in eRF3 gene-interfered Euplotes cells, suggesting that eRF3 is probably involved in the morphological organization of nuclei. This suggests that eRF3 is a multifunctional protein with roles additionals to its function in the process of termination of protein synthesis. 相似文献
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空气负离子对自发和环磷酰胺诱发的小鼠骨髓嗜多染性成红细胞微核率的影响 总被引:2,自引:0,他引:2
我们以前的研究表明负离子对~(60)Co-γ线诱发的急性和慢性损伤有明显的防护作用。本文以小鼠骨髓嗜多染性成红细胞(PCE)微核率为指标,探讨负离子对正常小鼠有无细胞毒性和对环磷酰胺(CP)诱发的遗传损伤有无防护作用。用负离子处理昆明小鼠60天后不注射CP直接取样;用负离子分别处理小鼠15天、30天和60天后注射CP,6小时后取样。镜检骨髓PCE微核并做统计处理。结果表明,负离子促进小鼠的生长发育且不导致潜在损伤;负离子对CP诱发的遗传损伤有明显的防护作用。 相似文献