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61.
The function of NS4B is incompletely understood. The aim of the study is to understand the influence of NS4B on anti-viral response. After cell line stably expressing NS4B established, the influence of IFN-alpha of different concentration on VSV was studied using plaque assay; cell expression profiling caused by NS4B was studied using DNA microarray, and the IFNGR1 fluorescence intensity was analyzed. Our data showed that HCV-NS4B could suppress immuno-associated gene expression, in particular, IFN-gamma receptor signal transduction-related genes. Taken together, NS4B could play some roles in HCV resistance to IFN therapy. 相似文献
62.
Apple Sucrose Transporter SUT1 and Sorbitol Transporter SOT6 Interact with Cytochrome b5 to Regulate Their Affinity for Substrate Sugars 总被引:1,自引:0,他引:1
Ren-Chun Fan Chang-Cao Peng Yan-Hong Xu Xiao-Fang Wang Yan Li Yi Shang Shu-Yuan Du Rui Zhao Xiao-Yan Zhang Ling-Yun Zhang Da-Peng Zhang 《Plant physiology》2009,150(4):1880-1901
Sugar transporters are central machineries to mediate cross-membrane transport of sugars into the cells, and sugar availability may serve as a signal to regulate the sugar transporters. However, the mechanisms of sugar transport regulation by signal sugar availability remain unclear in plant and animal cells. Here, we report that a sucrose transporter, MdSUT1, and a sorbitol transporter, MdSOT6, both localized to plasma membrane, were identified from apple (Malus domestica) fruit. Using a combination of the split-ubiquitin yeast two-hybrid, immunocoprecipitation, and bimolecular fluorescence complementation assays, the two distinct sugar transporters were shown to interact physically with an apple endoplasmic reticulum-anchored cytochrome b5 MdCYB5 in vitro and in vivo. In the yeast systems, the two different interaction complexes function to up-regulate the affinity of the sugar transporters, allowing cells to adapt to sugar starvation. An Arabidopsis (Arabidopsis thaliana) homolog of MdCYB5, AtCYB5-A, also interacts with the two sugar transporters and functions similarly. The point mutations leucine-73 → proline in MdSUT1 and leucine-117 → proline in MdSOT6, disrupting the bimolecular interactions but without significantly affecting the transporter activities, abolish the stimulating effects of the sugar transporter-cytochrome b5 complex on the affinity of the sugar transporters. However, the yeast (Saccharomyces cerevisiae) cytochrome b5 ScCYB5, an additional interacting partner of the two plant sugar transporters, has no function in the regulation of the sugar transporters, indicating that the observed biological functions in the yeast systems are specific to plant cytochrome b5s. These findings suggest a novel mechanism by which the plant cells tailor sugar uptake to the surrounding sugar availability. 相似文献
63.
细胞因子Midkine(简称MK)是新发现的一类肝素结合因子家族中的一员。1988年,Kadamatsu等利用差异杂交法在经维甲酸诱导分化的小鼠畸胎瘤细胞株HM-1中首先克隆到小鼠MK基因。人MK基因则最早是从λgt10人胚肾(20-24周)cDNA库和EMBL-3人胎盘基因组库获得。成熟 相似文献
64.
65.
Jianxin Fu Shuai Qi Liwen Yang Yi Dai Silan Dai 《Plant Molecular Biology Reporter》2014,32(3):740-749
The MADS-box gene SOC1/TM3 (SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1/ Tomato MADS-box gene 3) is a main integrator in the Arabidopsis flowering pathway; its structure and function are highly conserved in many plant species. SOC1-like genes have been isolated in chrysanthemum, one of the most well-known ornamental plants, but it has not been well characterized thus far. We isolated and characterized ClSOC1-1 and ClSOC1-2, two putative orthologs of Arabidopsis SOC1, from the wild diploid chrysanthemum, Chrysanthemum lavandulifolium, to investigate the regulatory mechanisms of flowering time control in chrysanthemum. Expression analysis indicated that ClSOC1-1 and ClSOC1-2 were expressed in all examined organs/tissues (leaves, shoot apices, petioles, stems and roots) with different expression levels, and with high expression in the shoot apices and leaves during the early stage of floral transition. The expression levels of ClSOC1-1 and ClSOC1-2 in the shoot apices increased at different developmental stages with the highest expression levels after 7 days of short-day treatment. Overexpression of ClSOC1-1 and ClSOC1-2 in wild-type Arabidopsis resulted in early flowering, which was coupled with the upregulation of one of the flowering promoter genes LEAFY. Our results suggested that the ClSOC1-1 and ClSOC1-2 genes play an evolutionarily conserved role in promoting flowering in Chrysanthemum lavandulifolium and could serve as a vital target for the genetic manipulation of flowering time in the chrysanthemum. 相似文献
66.
小鼠子宫颈部位输卵管蛋白表达的初步研究 总被引:2,自引:0,他引:2
用RT-PCR及免疫印迹法检测证实小鼠子宫颈粘膜上皮细胞具表达输卵管蛋白的能力,宫颈部所获得的输卵管蛋白转录产物, 310到 714的405bp的cDNA片段经序列测定及blast比较表明与输卵管部位表达的输卵管蛋白完全一致(100%)。小鼠子宫颈输卵管蛋白在动情周期的表达波动情况与输卵管粘膜上皮的类似,其表达于小鼠动情期明显增加。Westernblot显示小鼠子宫颈提取物中存在两种不同分子量(60KD,30KD)的输卵管蛋白。原位杂交结果则提示子宫颈粘膜上皮细胞含丰富的输卵管蛋白mRNA信号。通过"原体中风"实验未发现输卵管蛋白在体外对精子活动有影响,其功能尚须进一步分析。 相似文献
67.
68.
Artesunate exerts an anti‐immunosuppressive effect on cervical cancer by inhibiting PGE2 production and Foxp3 expression 下载免费PDF全文
69.
Pei Y Hancock PJ Zhang H Bartz R Cherrin C Innocent N Pomerantz CJ Seitzer J Koser ML Abrams MT Xu Y Kuklin NA Burke PA Sachs AB Sepp-Lorenzino L Barnett SF 《RNA (New York, N.Y.)》2010,16(12):2553-2563
Effective small interfering RNA (siRNA)-mediated therapeutics require the siRNA to be delivered into the cellular RNA-induced silencing complex (RISC). Quantitative information of this essential delivery step is currently inferred from the efficacy of gene silencing and siRNA uptake in the tissue. Here we report an approach to directly quantify siRNA in the RISC in rodents and monkey. This is achieved by specific immunoprecipitation of the RISC from tissue lysates and quantification of small RNAs in the immunoprecipitates by stem-loop PCR. The method, expected to be independent of delivery vehicle and target, is label-free, and the throughput is acceptable for preclinical animal studies. We characterized a lipid-formulated siRNA by integrating these approaches and obtained a quantitative perspective on siRNA tissue accumulation, RISC loading, and gene silencing. The described methodologies have utility for the study of silencing mechanism, the development of siRNA therapeutics, and clinical trial design. 相似文献
70.
Al Atalah B Rougé P Smith DF Proost P Lasanajak Y Van Damme EJ 《Glycoconjugate journal》2012,29(7):467-479
Rice (Oryza sativa) expresses different putative carbohydrate-binding proteins belonging to the class of lectins containing an Euonymus lectin (EUL)-related domain, one of them being OrysaEULS2. The OrysaEULS2 sequence consists of a 56 amino acid N-terminal domain followed by the EUL sequence. In this paper the original sequence of the EUL domain of OrysaEULS2 and some mutant forms have been expressed in Pichia pastoris. Subsequently, the recombinant proteins were purified and their carbohydrate binding properties determined. Analysis of the original protein on the glycan array revealed interaction with mannose containing structures and to a lesser extent with glycans containing lactosamine related structures. It was shown that mutation of tryptophan residue 134 into leucine resulted in an almost complete loss of carbohydrate binding activity of OrysaEULS2. Our results show that the EUL domain in OrysaEULS2 interacts with glycan structures, and hence can be considered as a lectin. However, the binding of the protein with the array is much weaker than that of other EUL-related lectins. Furthermore, our results indicate that gene divergence within the family of EUL-related lectins lead to changes in carbohydrate binding specificity. 相似文献