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151.
Moloney leukemia virus 10 protein (MOV10) is an interferon (IFN)-inducible RNA helicase implicated in antiviral activity against RNA viruses, yet its role in herpesvirus infection has not been investigated. After corneal inoculation of mice with herpes simplex virus 1 (HSV-1), we observed strong upregulation of both MOV10 mRNA and protein in acutely infected mouse trigeminal ganglia. MOV10 suppressed HSV-1 replication in both neuronal and non-neuronal cells, and this suppression required the N-terminus, but not C-terminal helicase domain of MOV10. MOV10 repressed expression of the viral gene ICP0 in transfected cells, but suppressed HSV-1 replication independently of ICP0. MOV10 increased expression of type I IFN in HSV-1 infected cells with little effect on IFN downstream signaling. Treating the cells with IFN-α or an inhibitor of the IFN receptor eliminated MOV10 suppression of HSV-1 replication. MOV10 enhanced IFN production stimulated by cytoplasmic RNA rather than DNA. IKKε co-immunoprecipitated with MOV10 and was required for MOV10 restriction of HSV-1 replication. Mass spectrometry identified ICP27 as a viral protein interacting with MOV10. Co-immunoprecipitation results suggested that this interaction depended on the RGG box of ICP27 and both termini of MOV10. Overexpressed ICP27, but not its RGG-Box deletion mutant, rendered MOV10 unable to regulate HSV-1 replication and type I IFN production. In summary, MOV10 is induced to restrict HSV-1 lytic infection by promoting the type I IFN response through an IKKε-mediated RNA sensing pathway, and its activity is potentially antagonized by ICP27 in an RGG box dependent manner.  相似文献   
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153.
Phenotypic plasticity and local adaptation are viewed as the main factors that result in between-population variation in phenotypic traits,but contributions of ...  相似文献   
154.
Adenovirus vectors with E1 deleted of the human serotype 5 (AdHu5) and the chimpanzee serotype 68 (AdC68) expressing the glycoprotein of the Evelyn Rokiniki Abelseth strain of rabies virus were tested upon oral application for induction of systemic and mucosal transgene product-specific antibody responses in mice. Both vectors induced systemic and mucosal antibodies to rabies virus, including virus-neutralizing antibodies and protection against a severe intracerebral challenge with a mouse-adapted strain of rabies virus. Pre-existing immunity of AdHu5 virus, which dampens induction of transgene product-specific immunity elicited by AdHu5 vectors given systemically did not impair the response induced by oral vaccination. Oral priming-boosting regimens with either heterologous or homologous adenoviral vectors used sequentially increased both mucosal and systemic antibody titers to rabies virus [corrected]  相似文献   
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156.
随着质谱技术和NMR等仪器测定技术的飞速发展,利用大规模质谱技术可以得到海量蛋白质的质谱数据。同时,利用NMR技术也可获得蛋白质的精确三维结构数据。这些数据以及面向这些数据的分析方法使得蛋白质组研究迅速发展,其基础理论和技术方法,都在不断地进步和完善。利用信息工程技术辅助生物学家开展面向质谱技术的高温量蛋白识别,面向NMR的蛋白质三维结构识别,以及功能发现研究,已经成为蛋白质组中的生命科学与信息科学交叉研究的热点和挑战问题。本文侧重从信息技术的角度对上述问题进行综述,并提出我们解决问题的思路和方法。  相似文献   
157.
热球菌目(Thermococcales)是一类分离自浅海热泉或者深海热液口的超嗜热微生物,包括火球菌(Pyrococcus)、热球菌(Thermococcus)、古老球菌(Palaeococcus)。研究其生命活动的分子机制,基因的功能等必须借助遗传操作系统。由于选择标记的限制,Thermococcales遗传操作系统落后于其他菌株。近年来,在Thermococcales发现了内源质粒并可以将其改造用作遗传工具。如在Thermococcus kodakarensis及Pyrococcus furious等菌株内都建立了成熟的遗传系统,并用于基因敲除以及基因表达。将就Thermococcales内源质粒的发现和遗传操作系统的发展与应用加以阐述。  相似文献   
158.
重组人干扰素—β的中试研究   总被引:1,自引:0,他引:1  
从大肠杆菌中大规模纯化新型干扰素β(IFN-βser17).首先建立IFN-βser17发酵和纯化工艺,连续大量纯化三批,并对纯化终产品进行全面鉴定.建立了稳定的发酵和纯化工艺流程,中试三批菌产量平均为4.33g/L,IFNβser17的表达量平均为20%,经破碎、粗提、精制后IFN-βser17的比活达2×107IU/mg以上,纯度超过96%,其他检定项目也均符合规程要求.  相似文献   
159.
Lack of guidelines for personalized chemotherapy treatment after surgery has caused gastric cancer (GC) patients' unnecessary exposure to toxicity and the financial burden of chemotherapy treatments. In our study, we aimed to identify potential biomarkers to predict GC patients' susceptibility to platinum-based on Gene Expression Omnibus (GEO) data sets. A total of 603 differentially expressed genes (DEGs) were identified between platinum-resistant cell lines and platinum-sensitive cell lines based on the Cancer Cell Line Encyclopedia (CCLE) data sets. A total of 253 patients who had accepted radical gastrectomy were recruited, of which 97 received platinum-based chemotherapy and 156 were untreated. Three biomarkers (BRMS1, ND6, SRXN1) were then selected by univariate and multivariate Cox regression analysis to establish the predictive models using nomogram. Then this model was further validated through the GEO data set (GSE62254) which showed that this model could precisely predict the disease-free survival and overall survival of patients treated with platinum-based chemotherapy after surgery compared with untreated GC patients (P < 0.0001). This predictive model might provide helpful messages about the patients' susceptibility to platinum to guide personalized chemotherapy.  相似文献   
160.
花生幼胚在含2,4-D的诱导培养基中,形成近球状的致密的胚性愈伤组织、杆状两极结构及子叶期体胚。继代培养也有体胚发生。光照明显抑制体胚发生类似于自然栽培的情况。成熟培养基中诱导体胚根、芽两极发育完全。光下,具有根、芽的体胚于再生培养基中长成小植株后移栽于盛沙土的盆中正常生长、结实。在较好的影响因素(光照、幼胚长度、激素、切分方式、接种密度)组合下,体胚发生频率达75%以上,每子叶形成体胚3个以上。该体细胞胚高效再生系统与合子胚的发育相似,是遗传转化和胚发育研究的良好系统。  相似文献   
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