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31.
32.
该研究采用同源克隆与PCR扩增方法,从马铃薯品种‘Desiree’中克隆植物磺肽素受体基因StPSKR1和StPSKR2的全长cDNA,并对其进行生物信息学分析及亚细胞定位分析,为深入研究StPSKR1和StPSKR2基因在马铃薯生长发育和生物胁迫中的作用提供理论依据。结果发现:(1)通过同源克隆与PCR扩增获得StPSKR1和StPSKR2的全长cDNA片段,并将其克隆到pGWB5-GFP载体;测序结果显示这2个基因编码的蛋白质与数据库给定的蛋白质序列保持一致,表明成功克隆到StPSKR1和StPSKR2基因。(2)StPSKR1位于马铃薯1号染色体上,cDNA全长3 042 bp,编码1 013个氨基酸,预测蛋白相对分子质量为112.16 kD,理论等电点6.27;StPSKR2位于7号染色体,cDNA全长3 135 bp,编码1 044个氨基酸,相对分子量为114.99 kD,理论等电点6.19。(3)生物信息学分析显示,StPSKR1和StPSKR2都属于跨膜蛋白。(4)亚细胞定位结果显示,StPSKR1和StPSKR2均定位于细胞膜上。 相似文献
33.
中药有效成分治疗类风湿关节炎研究进展 总被引:3,自引:0,他引:3
中药治疗类风湿性关节炎(RA)有几千年的临床应用历史,积累了丰富的经验.近年来,国内外针对中药复方和单味药的抗RA作用开展了大量的实验研究工作,很多中药的活性成分(组分)和作用机制得到初步阐明,开发出青藤碱注射液、雷公藤多苷片和白芍总苷片等新型RA治疗药物.本文对中药有效成分在治疗RA方面的研究进展进行综述. 相似文献
34.
Gao Y Yue W Zhang P Li L Xie X Yuan H Chen L Liu D Yan F Pei X 《Biochemical and biophysical research communications》2005,335(2):343-350
spindlin1, a novel human gene recently isolated by our laboratory, is highly homologous to mouse spindlin gene. In this study, we cloned cDNA full-length of this novel gene and send it to GenBank database as spindlin1 (Homo sapiens spindlin1) with Accession No. AF317228. In order to investigate the function of spindlin1, we studied further the subcellular localization of Spindlin1 protein and the effects of spindlin1 overexpression in NIH3T3 cells. The results showed that the fusion protein pEGFP-N1-spindlin1 was located in the nucleus and the C-terminal is correlated with nuclear localization of Spindlin1 protein. NIH3T3 cells which could stably express spindlin1 as a result of RT-PCR analysis compared with the control cells displayed a complete morphological change; made cell growth faster; and increased the percentage of cells in G2/M and S phase. Furthermore, overexpressed spindlin1 cells formed colonies in soft agar in vitro and formed tumors in nude mice. Our findings provide direct evidence that spindlin1 gene may contribute to tumorigenesis. 相似文献
35.
Zhou L Liu Q Wang Q Ma Y Xu Y Yang Z Zhao Y Zhang Y 《Applied microbiology and biotechnology》2008,79(6):1027-1034
To synthesize and secrete heterologous proteins in an attenuated Vibrio anguillarum strain for potential multivalent live vaccine development, different antigen-delivery systems based on bacterial-originated secretion signal peptides (SPs) were designed and identified in this work. Four SPs were derived from hemolysin of Escherichia coli, RTX protein of V. cholerae, hemolysin of V. anguillarum, zinc-metalloprotease of V. anguillarum, respectively, and their abilities to support secretion of green fluorescent protein (GFP) in an attenuated V. anguillarum strain MVAV6203 were assayed. Immunodetection of GFP showed that the capability of the tested signal leaders to direct secretion of GFP varied greatly. Although all the four signal peptide-fused GFPs could be expressed correctly and trapped intracellularly in recombinant strains, only the EmpA signal peptide could confer efficient secretion to GFP. For the investigation of its potential application in live bacteria carrier vaccines, a heterologous protein EseB of Edwardsiella tarda was fused to the SP(empA) antigen-delivery system and introduced into the strain MVAV6203. Further analysis of EseB demonstrated that the constructed SP(empA) antigen-delivery system could be used to secrete foreign protein in attenuated V. anguillarum and be available for carrier vaccines development. 相似文献
36.
Xiaowei Xu Sulin Ren Xiaoxiao Chen Jun Ge Zhenxing Xu Hongying Huang Honglin Sun Yue Gu Tong Zhou Jianqiang Li Hanmei Xu 《Virologica Sinica》2014,(6)
Despite the long availability of a traditional prophylactic vaccine containing the HBV surface antigen(HBsA g) and aluminum adjuvant, nearly 10% of the population remains unable to generate an effective immune response. Previous studies have indicated that hepatitis B virus(HBV) PreS 2-S is abundant in T/B cell epitopes, which induces a stronger immune response than HBsA g, particularly in terms of cytotoxic T lymphocyte(CTL) reaction. In the current study, the HBV PreS 2-S gene encoding an extra26 amino acids(PreS 2 C-terminus) located at the N-terminus of HBsA g was cloned into the pV CH1300 expression vector. Pre S2-S expressed in the methylotrophic yeast, Hansenula polymorpha, was produced at a yield of up to 250 mg/L. Subsequent purification steps involved hydrophobic adsorption to colloidal silica, ion-exchange chromatography and density ultracentrifugation. The final product was obtained with a total yield of ~15% and purity of ~99%. In keeping with previous studies, ~22 nm viruslike particles were detected using electron microscopy. The generated PreS 2-S antigen will be further studied for efficacy and safty in animals. 相似文献
37.
Zhen‐Yu Li Yu‐Cheng Gu Dianne Irwin Jacqueline Sheridan John Clough Ping Chen Shu‐Ying Peng Yi‐Ming Yang Yue‐Wei Guo 《化学与生物多样性》2009,6(10):1744-1750
Two new Daphniphyllum alkaloids, macropodumines J and K ( 1 and 2 , resp.), together with six known structurally related alkaloids, 3 – 8 , were isolated from the bark of Daphniphyllum macropodum Miq . The structures of the new compounds 1 and 2 were elucidated on the basis of a comprehensive analysis of their spectroscopic and chemical data. Macropodumine J ( 1 ) contains a CN group which is relatively rare in naturally occurring alkaloids. All isolated compounds were tested for their insecticidal activities against a number of insect species. Daphtenidine C ( 5 ) is the most active compound against Plutella xylostella. This is the first report of insecticidal properties of Daphniphyllum alkaloids. 相似文献
38.
Xi Jiang Jingyin Yue Huimei Lu Neil Campbell Qifeng Yang Shijie Lan Bruce G. Haffty Changji Yuan Zhiyuan Shen 《International journal of biological sciences》2013,9(1):67-77
Filamin-A cross-links actin filaments into dynamic orthogonal networks, and interacts with an array of proteins of diverse cellular functions. Because several filamin-A interaction partners are implicated in signaling of cell mobility regulation, we tested the hypothesis that filamin-A plays a role in cancer metastasis. Using four pairs of filamin-A proficient and deficient isogenic cell lines, we found that filamin-A deficiency in cancer cells significantly reduces their migration and invasion. Using a xenograft tumor model with subcutaneous and intracardiac injections of tumor cells, we found that the filamin-A deficiency causes significant reduction of lung, splenic and systemic metastasis in nude mice. We evaluated the expression of filamin-A in breast cancer tissues by immunohistochemical staining, and found that low levels of filamin-A expression in cancer cells of the tumor tissues are associated with a better distant metastasis-free survival than those with normal levels of filamin-A. These data not only validate filamin-A as a prognostic marker for cancer metastasis, but also suggest that inhibition of filamin-A in cancer cells may reduce metastasis and that filamin-A can be used as a therapeutic target for filamin-A positive cancer. 相似文献
39.
胞红蛋白是珠蛋白家族中的新成员,在组织中有广泛表达,但这种表达只限于成纤维细胞及其衍生细胞中,且定位在细胞质中.最初认为胞红蛋白与其它珠蛋白在功能上有一定的相似性,如携带氧至线粒体、作为氧的感受器等.但胞红蛋白的特殊结构及主要定位与上述功能并不完全相符.越来越多的研究认为胞红蛋白参与纤维化形成,并且其过表达可以对抗损伤导致的氧化应激,从而抑制自由基介导的成纤维细胞的活化及组织的纤维化. 相似文献
40.
本文论述了采自黑龙江省哈尔滨市和尚志县帽儿山附近污水沟和水塘内的裸藻,发现 8个新种、2新变种。新种为哈尔滨裸藻Euglena harbinica sp.nov,帽儿山裸藻E.maorshanica sp.nov,美丽裸藻E.pulchera sp.nov,匍匐裸藻E.repens sp.nov,点纹裸藻E.punctulata sp.nov,变形裸藻E.amoeboides sp.nov,龙江裸藻E.lonjianica sp.nov,梨形裸藻E.pyriformis sp.nov.;2新变种均为三棱裸藻E.tripteris(Duj.)Klebs的变种,即复合三棱裸藻var.complexa var.nov.和单粒三棱裸藻vnr.simplexa var.nov.。 相似文献