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41.
Overexpression of Hsp90 from grass carp (Ctenopharyngodon idella) increases thermal protection against heat stress 总被引:1,自引:0,他引:1
With homologous DNA probes, we had screened a grass carp heat shock protein 90 gene (CiHsp90). The full sequence of CiHsp90 cDNA was 2793 bp, which could code a 798 amino acids peptide. The phylogenetic analysis demonstrated that CiHsp90 shared the high homology with Zebrafish Grp94. Quantitative RT-PCR analysis showed that CiHsp90 was ubiquitously expressed at lower levels in all detected tissues and up-regulated after heat shock at 34 °C or cold stress at 4 °C. To understand the function of CiHsp90 involving in thermal protection, an expression vector containing coding region cDNA was expressed in E. coli BL21 (DE3) plysS. Upon transfer from 37 °C to 42 °C, these cells that accumulated CiHsp90 peptides displayed greater thermoresistance than the control cells. While incubated at 4°C for different periods, it could also improve the cell viability. After transient transfected recombinant plasmid pcDNA3.1/CiHsp90 into mouse myeloma cell line SP2/0, we found that CiHsp90 could contribute to protecting cells against both thermal and cold extremes. On the contrary, the mutant construct ΔN-CiHsp90 (256-798aa) could abolish the protection activity both in prokaryotic cells and eukaryotic cells. Additionally, both CiHsp90 and ΔN-CiHsp90 peptides could reduce the level of citrate synthase aggregation at the high temperature. 相似文献
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PLNPK is a pentapeptide compound extracted from pig spleen with a Pro-Leu-Asn-Pro-Lys molecular structure. The spleen is the biggest immune organ in the body, in which there are lots of immunocytes and immune molecules. Our pilot study showed that PLNPK could suppress the transformation and proliferation of T lymphocytes and the production of antibodies in mice. It is widely accepted that most types of glomerulonephritis are immunological diseases caused by the reaction of antigen and antibody. Both humoral immunity and cell-mediated immunity contribute to the progress of these diseases, and suppression of immunoreactions and inflammation is important to ameliorate nephritis. After the immunosuppressive effects of this compound were discovered, this study also examined whether PLNPK had beneficial effects on a rat model of glomerulonephritis. The results suggested PLNPK (200microg/kg/d and 400microg/kg/d) reduced urinary protein excretion, lessened the deposit of autoantibodies along the glomerular basement membrane (GBM), reduced formation of crescent and protein casts, and ameliorated glomerular fibrosis and GBM injury. After treatment with PLNPK (200microg/kg/d and 400microg/kg/d) for 7 days, macrophage infiltration in the glomeruli was markedly reduced. Our results suggest that PLNPK has a beneficial effect on rat anti-GBM nephritis. 相似文献
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15-Deoxy-Delta 12,14-prostaglandin J2 (15d-PGJ2), a cyclopentenone prostaglandin, displays a potent anti-inflammatory effect at micromolar concentrations (>2 microM) through direct inhibition of nuclear factor (NF)-kappa B activation. Here we show that at submicromolar concentrations (0.1-0.5 microM) 15d-PGJ2 retains the ability to suppress the production of tumor necrosis factor-alpha (TNF-alpha) and nitric oxide (NO) in lipopolysaccharide (LPS)-activated murine J774 macrophages under the conditions of a prolonged incubation (>12 h). Western blot analysis revealed that the expression of the cytoprotective enzyme, heme oxygenase-1 (HO-1), was induced and coincident with the anti-inflammatory action of 15d-PGJ2. Inhibition of HO-1 activity or scavenging carbon monoxide (CO), a byproduct derived from heme degradation, significantly attenuated the suppressive activity of 15d-PGJ2. Furthermore, LPS-induced NF-kappa B activation assessed by the inhibitory protein of NF-kappa B(I kappa B) degradation and p50 nuclear translocation was diminished in cells subjected to prolonged treatment with the low concentration of 15d-PGJ2. Treatment of cells with the protein synthesis inhibitor, cycloheximide, or the specific p38 MAP kinase inhibitor, SB203580, blocked the induction of HO-1 and suppression of LPS-induced I kappa B degradation mediated by 15d-PGJ2. Likewise, HO inhibitor and CO scavenger were effective in abolishing the inhibitory effects of 15d-PGJ2 on NF-kappa B activation induced by LPS. The functional role of CO was further demonstrated by the use of a CO releasing molecule, tricarbonyldichlororuthenium(II) dimer, which significantly suppressed LPS-induced nuclear translocation of p50 as assessed by confocal immunofluorescence. Collectively, these data suggest that even at submicromolar concentrations 15d-PGJ2 can exert an anti-inflammatory effect in macrophages through a mechanism that involves the action of HO/CO. 相似文献
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Hui-Ling Jiang Hui-Hui Yang Yu-Biao Liu Jia-Xi Duan Xin-Xin Guan Chen-Yu Zhang Wen-Jing Zhong Ling Jin Dai Li Qing Li Yong Zhou Cha-Xiang Guan 《Journal of cellular physiology》2024,239(2):e31169
Alveolar epithelial cell (AEC) necroptosis is critical to disrupt the alveolar barrier and provoke acute lung injury (ALI). Here, we define calcitonin gene-related peptide (CGRP), the most abundant endogenous neuropeptide in the lung, as a novel modulator of AEC necroptosis in lipopolysaccharide (LPS)-induced ALI. Upon LPS-induced ALI, overexpression of Cgrp significantly mitigates the inflammatory response, alleviates lung tissue damage, and decreases AEC necroptosis. Similarly, CGRP alleviated AEC necroptosis under the LPS challenge in vitro. Previously, we identified that long optic atrophy 1 (L-OPA1) deficiency mediates mitochondrial fragmentation, leading to AEC necroptosis. In this study, we discovered that CGRP positively regulated mitochondrial fusion through stabilizing L-OPA1. Mechanistically, we elucidate that CGRP activates AMP-activated protein kinase (AMPK). Furthermore, the blockade of AMPK compromised the protective effect of CGRP against AEC necroptosis following the LPS challenge. Our study suggests that CRGP-mediated activation of the AMPK/L-OPA1 axis may have potent therapeutic benefits for patients with ALI or other diseases with necroptosis. 相似文献
46.
Hui-Ling Ma Selim Kermasha Jin-Ming Gao Rogelio Morales Borges Xiu-zhu Yu 《Journal of Molecular Catalysis .B, Enzymatic》2009,57(1-4):89-95
Rhus vernificera laccase-catalyzed oxidation of phenolic compounds, i.e., (+)-catechin, (−)-epicatechin and catechol, was carried out in selected organic solvents to search for the favorable reaction medium. The investigation on reaction parameters showed that optimal laccase activity was obtained in hexane at 30 °C, pH 7.75 for the oxidation of (+)-catechin as well as for (−)-epicatechin, and in toluene at 35 °C, pH 7.25 for the oxidation of catechol. Ea and Q10 values of the biocatalysis in the reaction media of the larger log p solvents like isooctane and hexane were relatively higher than those in the reaction media of lower log p solvents like toluene and dichloromethane. Maximum laccase activity in the organic media was found with 6.5% of buffer as co-solvent. A wider range of 0–28 μg protein/ml in hexane than that of 0–16.7 μg protein/ml in aqueous medium was observed for the linear increasing conversion of (+)-catechin. The kinetic studies revealed that in the presence of isooctane, hexane, toluene and dichloromethane, the Km values were 0.77, 0.97, 0.53 and 2.9 mmol/L for the substrate of (+)-catechin; 0.43, 0.34, 0.14 and 3.4 mmol/L for (−)-epicatechin; 2.9, 1.8, 0.61 and 1.1 mmol/L for catechol, respectively, while the corresponding Vmax values were 2.1 × 10−2, 2.3 × 10−2, 0.65 × 10−2 and 0.71 × 10−2 δA/μg protein min); 1.8 × 10−2, 0.88 × 10−2, 0.19 × 10−2 and 1.0 × 10−2 δA/μg protein min); 0.48 × 10−2, 0.59 × 10−2, 0.67 × 10−2 and 0.54 × 10−2 δA/μg protein min), respectively. FT-IR indicated the formation of probable dimer from (+)-catechin in organic solvent. These results suggest that this laccase has higher catalytic oxidation capacity of phenolic compounds in suitable organic media and favorite oligomers could be obtained. 相似文献
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为调查广东地区汉族人群中是否存在着亚群结构,对来自广州、佛山、东莞、江门和中山-珠海5个不同地区的471随机个体血样本进行15个STR的基因分型,并作Hardy-Weinberg平衡检验,比较群体之间的等位基因频率,计算这个5个地区人群间的共祖系数。结果显示,广东汉族人群没有明显的Hardy-Weinberg不平衡,5个地区人群的等位基因分布均没有差异,他们之间的共祖系数小于0.01。因此,广东地区汉族人群中没有明显的亚群结构。
Abstract:To investigate the subpopulation structure within the Han Population in Guandong area,a total of 471 DNA samples from five populations in Guandong Province,including Guangzhou,Foshan,Dongguan,Jiangmen and Zhongshan-Zhuhai region,were genotyped at 15 STR(short tandem repeats) markers.Hardy-Weinberg tests were performed,allele frequencies were compared,and the genetic coancestry coefficient(FST ) was estimated.The results did not show significant departure from Hardy-Weinberg equilibrium in the total population.Difference of allele frequencies among these populations was not observed,and the coancestry coefficient(FST)was less than 0.01.Subpopulation structure within Han Population in Guandong Province could not be detected. 相似文献
49.
Yun-Feng Zhang Chun-Yong Zhang Ting Zhang Hui-Ling Guan Sheng-Qi Yan 《Plant Systematics and Evolution》2010,285(3-4):245-257
Campanumoea is a small genus in the family Campanulaceae, with species divided into sections Campanumoea and Cyclocodon. Sixteen accessions from Campanumoea and related genera native to China were used to study their karyotype. The results showed that chromosome characteristics were different between the two sections. For Campanumoea, the karyotypic formula was 2n = 2X = 2m + 12sm + 2st = 16,3A and for Cyclocodon it was 2n = 2X = 6m + 12sm = 18,3B. These data, combined with chromosomal length characteristics, support the restoration of section Cyclocodon as a genus. However, the incorporation of section Campanumoea into Codonopsis requires more evidence. Comparison of chromosomal length and haploid set length revealed that chromosomal segment rearrangements occurred within sections of Campanumoea and between genera, with the difference within sections being greater than that between genera. Therefore, chromosomal segment rearrangements are present in Campanulaceae, implying that chromosomal segment rearrangement plays an important role in the evolution of diversity in Campanulaceae. By comparing the chromosomal characteristic in section Campanumoea and the genus Adenophora, we concluded that the secondary chromosome type such as n = 17, 18 would be derived by autopolyploidization of n = 9, and by chromosome fusion. 相似文献
50.
Proviral progeny of heterodimeric virions reveal a high crossover rate for human immunodeficiency virus type 2 下载免费PDF全文
Human immunodeficiency virus type 1 (HIV-1), the causative agent of AIDS in humans, exhibits a very high rate of recombination. Bearing in mind the significant epidemiological and clinical contrast between HIV-2 and HIV-1 as well as the critical role that recombination plays in viral evolution, we examined the nature of HIV-2 recombination. Towards this end, a strategy was devised to measure the rate of crossover of HIV-2 by evaluating recombinant progeny produced exclusively by heterodimeric virions. The results showed that HIV-2 exhibits a crossover rate similar to that of HIV-1 and murine leukemia virus, indicating that the extremely high rate of crossover is a common retroviral feature. 相似文献