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Longxi Mao Shilian Le Xin Jin Guoliang Liu Jun Chen Junwen Hu 《Experimental cell research》2019,374(2):274-281
COP9 signalosome subunit 5 (CSN5) has been involved in the progression of diverse human cancers. MMP2 plays an important role in the metastasis of cancer cells. However, the roles and relationship of in pancreatic cancer (PC) is still unknown. Here, our data shown that both CSN5 and MMP2 were significantly upregulated in PC compared with the corresponding adjacent tissues, where a positive correlation in their expression and associated malignant characteristics were found. Further, silencing of CSN5 expression markedly inhibited PC invasion and metastasis in vitro and in vivo, accompanied by decreased MMP2 expression. Moreover, the anti-metastasis role of CSN5 silence was reversed by MMP2 overexpression, whereas knockdown of MMP2 decreased PC metastasis driven by upregulation of CSN5. Further investigation revealed that CSN5 regulated MMP2 expression via activation of FOXM1 in PC cells. Mechanistically, CSN5 directly bound FOXM1 and decreased its ubiquitination to enhance the protein stability of FOXM1. Taken together, the results indicate that CSN5 can contribute to PC invasion and metastasis through activation of FOXM1/MMP2 axis. 相似文献
63.
Retracted: Screening of candidate genes and fine mapping of drought tolerance quantitative trait loci on chromosome 4 in rice (Oryza sativa L.) under drought stress 下载免费PDF全文
Yuan‐Yuan Nie Lin Zhang Yun‐Hua Wu Hao‐Jie Liu Wei‐Wei Mao Juan Du Hai‐Lin Xiu Xiao‐Yu Wu Xia Li Yu‐Wei Yan Guo‐Lan Liu Hong‐Yan Liu Song‐Ping Hu 《Ecology and evolution》2015,5(21):5007-5015
Due to severe water resource shortage, genetics of and breeding for DT (drought tolerance) in rice (Oryza sativa L.) have become one of the hot research topics. Identification of grain yield QTLs (quantitative trait loci) directly related to the DT trait of rice can provide useful information for breeding new drought‐resistant and water‐saving rice varieties via marker‐assisted selection. A population of 105 advanced BILs (backcross introgression lines) derived from a cross between Zhenshan97B and IRAT109 in Zhenshan97B background were grown under drought stress in a field experiment and phenotypic traits were investigated. The results showed that in the target interval of RM273‐RM255 on chromosome 4, three main‐effect QTLs related to panicle length, panicle number, and spikelet number per panicle were identified (LOD [logarithm of the odds] > 2.0). The panicle length‐related QTL had two loci located in the neighboring intervals of RM17308‐RM17305 and RM17349‐RM17190, which explained 18.80% and 20.42%, respectively, of the phenotypic variation, while the panicle number‐related QTL was identified in the interval of RM1354‐RM17308, explaining 11.47% of the phenotypic variation. As far as the spikelet number per panicle‐related QTL was concerned, it was found to be located in the interval of RM17308‐RM17305, which explained 28.08% of the phenotypic variation. Using the online Plant‐GE query system, a total of 13 matched ESTs (expressed sequence tags) were found in the target region, and of the 13 ESTs, 12 had corresponding predicted genes. For instance, the two ESTs CB096766 and CA765747 were corresponded to the same predicted gene LOC_Os04g46370, while the other four ESTs, CA754286, CB000011, CX056247, and CX056240, were corresponded to the same predicted gene LOC_Os04g46390. 相似文献
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Shu-Yu Yu Bao-Lin Mao Ping Xiao Wei-Ping Yu Ying-Long Wang Chang-Zhi Huang Wang-Qiu Chen Xiang-Zhan Xuan 《Biological trace element research》1990,24(2-3):105-108
This pilot study evaluated the feasibility and effectiveness of conducting a double-blind clinical trial for the prevention of lung cancer with selenium (Se) in Yunnan Tin Corporation, the People's Republic of China, where the incidence rates of lung cancer are extraordinarily high among the miners. Forty healthy miners were randomized to either 300 μg of Se in high Se malt cakes or an identical placebo of malt cakes daily for one year. Subjects consumed their usual daily diet. The low Se concentrations in plasma (0.05±0.008 μg/mL) and hair (0.442±0.085 μg/g) reflected their low dietary Se intake in the control subjects. In Se-supplemented group, the Se status was increased by 178% for serum and 194.8% for hair. The serum GSHpx activity was increased by 155.7%, whereas the lipid peroxide level was reduced by 74.5% compared to the placebo. The results of UDS assay indicated that the lymphocyte DNA damage induced by ultraviolet irradiation and carcinogen 3,4-benzpyrene could be protected by Se supplementation. Se-supplementation did not affect the liver function test (SGPT), as well as the concentrations of hemoglobin, albumin, and cholesterol. Thus, daily intake of 300 μg Se in form of Se-malt as a chemopreventive measure is safe and effective to humans with low Se status. 相似文献
65.
Xiaowei Guo Xiali Mao Wu Yu Liujun Xiao Mingming Wang Shuai Zhang Jinyang Zheng Hangxin Zhou Lun Luo Jinfeng Chang Zhou Shi Zhongkui Luo 《Global Change Biology》2023,29(3):909-920
Soil biogeochemical processes may present depth-dependent responses to climate change, due to vertical environmental gradients (e.g., thermal and moisture regimes, and the quantity and quality of soil organic matter) along soil profile. However, it is a grand challenge to distinguish such depth dependence under field conditions. Here we present an innovative, cost-effective and simple approach of field incubation of intact soil cores to explore such depth dependence. The approach adopts field incubation of two sets of intact soil cores: one incubated right-side up (i.e., non-inverted), and another upside down (i.e., inverted). This inversion keeps soil intact but changes the depth of the soil layer of same depth origin. Combining reciprocal translocation experiments to generate natural climate shift, we applied this incubation approach along a 2200 m elevational mountainous transect in southeast Tibetan Plateau. We measured soil respiration (Rs) from non-inverted and inverted cores of 1 m deep, respectively, which were exchanged among and incubated at different elevations. The results indicated that Rs responds significantly (p < .05) to translocation-induced climate shifts, but this response is depth-independent. As the incubation proceeds, Rs from both non-inverted and inverted cores become more sensitive to climate shifts, indicating higher vulnerability of persistent soil organic matter (SOM) to climate change than labile components, if labile substrates are assumed to be depleted with the proceeding of incubation. These results show in situ evidence that whole-profile SOM mineralization is sensitive to climate change regardless of the depth location. Together with measurements of vertical physiochemical conditions, the inversion experiment can serve as an experimental platform to elucidate the depth dependence of the response of soil biogeochemical processes to climate change. 相似文献
66.
Long Xing‐yu Gong Jiang‐ning Deng Mao Wu Di Chen Zhuo Xia Pin‐hua Gong Xiao‐jian Deng Qin Shi Zhi‐hui Yan Xue‐mei Tian Ru‐qing Jiang Cai‐yun 《Luminescence》2019,34(3):316-323
A novel, rapid and sensitive chemiluminescence (CL) method for the determination of oxytetracycline hydrochloride (OTCH) is described in this paper. The presented method was based on the fact that OTCH could immensely enhance the CL of the reaction of cerium sulfate and tris(2,2‐bipyridyl) ruthenium (II) in acidic medium. Under optimal experimental conditions, CL intensity was favorably linear for OTCH in the range 5.0 × 10?7 to 5.0 × 10?5 g/ml, with a detection limit of 1.5 × 10?7 g/ml (S/N = 3). The relative standard detection was 4.76% for 5.0 × 10?6 g/ml (n = 11). This method was successfully applied to the analysis of OTCH in milk and egg white samples. According to the results of the kinetic curves for OTCH in the Ru(bipy)32+–Ce(SO4)2 CL system, together with CL and ultraviolet (UV)–visible spectra, the possible mechanism of the CL reaction is discussed briefly. 相似文献
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SnRK2基因对植物的逆境胁迫具有重要的调节作用,以马铃薯‘陇薯3号’(Solanum tuberosum)为试材,采用RT-PCR方法从马铃薯试管苗中克隆得到1个SnRK2.1基因cDNA,命名为StSnRK2.1,提交GenBank注册,注册号为JX280911。通过生物信息学分析,该基因开放阅读框全长1 008 bp,编码335个氨基酸。预测蛋白质分子量约为37.77 kD,等电点为5.37,蛋白质二级结构预测α-螺旋42.39%,延伸链16.42%,β-折叠7.46%,无规卷曲33.73%,具有疏水性,为膜内蛋白。亚细胞定位显示该基因出现在细胞质及微体中的可能性较大。肽链可能有7处丝氨酸磷酸化位点,2处苏氨酸磷酸化位点,以及3处酪氨酸磷酸化位点,因此推测该基因在植物抗逆中有重要的作用。 相似文献
70.
Xia Wei Chan Feng Xiao‐Hui Li Xing‐Xin Mao Hai‐Bin Luo Dong‐Mei Zhang Li Rong Zhen‐Yu Xie Xin Yu Jie Li Wen‐Cai Ye Xiao‐Jun Huang Cui‐Xian Zhang 《化学与生物多样性》2019,16(6)
One new racemic mixture, penicilliode A ( 1 ) and four pairs of enantiomeric polyketides, penicilliode B and C ( 2 and 3 ) and coniochaetone B and C ( 4 and 5 ), were obtained from the starfish‐derived symbiotic fungus Penicillium sp. GGF16‐1‐2. Interestingly, the strain GGF16‐1‐2 can produce enantiomers. The absolute configuration of 1 was determined by X‐ray diffraction (XRD) analysis, and the absolute configurations of 2 – 4 were determined by the optical rotation (OR) values and electronic circular dichroism (ECD) calculations. Compounds 1 – 5 were firstly isolated from the marine‐derived fungus Penicillium as racemates, and 2 – 5 were separated by HPLC with a chiral stationary phase. All the compounds were evaluated for their antibacterial, cytotoxic and inhibitory activities against PDE4D2. 相似文献