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71.
采用酶切连接和重叠PCR连接两种方法将抗黑色素瘤单链抗体基因和去除N端信号肽的金黄色葡萄球菌肠毒素A基因进行融合,并将融合基因克隆于pET28a表达载体上,转化大肠杆菌BL21(DE3)。用NiNTA系统对表达产物进行分离、纯化。MTT法检测融合蛋白对黑色素瘤细胞的体外抑制率。结果表明6HisScFvSEA融合蛋白可在E.coli BL21(DE3)中稳定表达,表达量占菌体蛋白的30%,主要以包涵体的形式存在。融合蛋白可通过激活效应细胞对表达相关抗原的黑色素瘤细胞发挥抑制作用。 相似文献
72.
Hai-bo Qiu Li-yi Zhang Chao Ren Zhao-lei Zeng Wen-jing Wu Hui-yan Luo Zhi-wei Zhou Rui-hua Xu 《PloS one》2013,8(3)
Purpose
Gastric cancer remains one of the leading causes of cancer death worldwide. Patients usually present late with local invasion or metastasis, for which there are no effective therapies available. Following previous studies that identified the adhesion molecule Cadherin-17(CDH17) as a potential marker for gastric carcinoma, we performed proof-of-principle studies to develop rational therapeutic approaches targeting CDH17 for treating this disease.Methods
Immunohistochemistry was used to study the expression of CDH17 in 156 gastric carcinomas, and the relationship between survival and CDH17 expression was studied by multivariate analyses. The effect of RNA interference–mediated knockdown of CDH17 on proliferation of gastric carcinoma cell lines was examined in vitro and in vivo, as well as the effects on downstream signaling by immunoblotting.Results
CDH17 was consistently up-regulated in human gastric cancers, and overall survival in patients with CDH17 upregulation was poorer than in those without expression of this gene (5 yrs overall survival rate 29.0% vs. 45.0%, P<0.01). Functional assays demonstrated that CDH17 knockdown inhibited cell proliferation, adhesion, migration, invasion, clonogenicity and induce G0/G1 arrest. In mice, shRNA-mediated CDH17 knockdown markedly inhibits tumor growth; intratumoral injection of CDH17 shRNAs results in significant antitumor effects on transplanted tumor models. The antitumor mechanisms underlying CDH17 inhibition involve inactivation of Wnt/β-catenin signaling.Conclusion
Our results identify CDH17 as a biomarker of gastric carcinoma and attractive therapeutic target for this aggressive malignancy. 相似文献73.
Sébastien Besseau Franziska Kellner Arnaud Lanoue Antje M.K. Thamm Vonny Salim Bernd Schneider Fernando Geu-Flores René H?fer Grégory Guirimand Anthony Guihur Audrey Oudin Ga?lle Glevarec Emilien Foureau Nicolas Papon Marc Clastre Nathalie Giglioli-Guivarc’h Benoit St-Pierre Danièle Werck-Reichhart Vincent Burlat Vincenzo De Luca Sarah E. O’Connor Vincent Courdavault 《Plant physiology》2013,163(4):1792-1803
74.
FANCJ/BRIP1 encodes a helicase that has been implicated in the maintenance of genomic stability. Here, to better understand
FANCJ function in DNA damage responses, we have examined the regulation of its cellular localization. FANCJ nuclear foci assemble
spontaneously during S phase and are induced by various stresses. FANCJ foci colocalize with the replication fork following
treatment with hydroxyurea, but not spontaneously. Using FANCJ mutants, we find that FANCJ helicase activity and the capacity
to bind BRCA1 are both involved in FANCJ recruitment. Given similarities to the recruitment of another Fanconi anemia protein,
FANCD2, we tested for colocalization of FANCJ and FANCD2. Importantly, these proteins show substantial colocalization, and
FANCJ promotes the assembly of FANCD2 nuclear foci. This process is linked to the proper localization of FANCJ itself since
both FANCJ and FANCD2 nuclear foci are compromised by FANCJ mutants that abrogate its helicase activity or interaction with
BRCA1. Our results suggest that FANCJ is recruited in response to replication stress and that FANCJ/BRIP1 may serve to link
FANCD2 to BRCA1. 相似文献
75.
Ren J Pashkova N Winistorfer S Piper RC 《The Journal of biological chemistry》2008,283(31):21599-21611
Ubiquitin (Ub) is a sorting signal that targets integral membrane proteins to the interior of the vacuole/lysosome by directing them into lumenal vesicles of multivesicular bodies (MVBs). The Vps27-Hse1 complex, which is homologous to the Hrs-STAM complex in mammalian cells, serves as a Ub-sorting receptor at the surface of early endosomes. We have found that Hse1 interacts with Doa1/Ufd3. Doa1 is known to interact with Cdc48/p97 and Ub and is required for maintaining Ub levels. We find that the Hse1 Src homology 3 domain binds directly to the central PFU domain of Doa1. Mutations in Doa1 that block Hse1 binding but not Ub binding do not alter Ub levels but do result in the missorting of the MVB cargo GFP-Cps1. Loss of Doa1 also causes a synthetic growth defect when combined with loss of Vps27. Unlike the loss of Doa1 alone, the doa1Delta vps27Delta double mutant phenotype is not suppressed by Ub overexpression, demonstrating that the effect is not due to indirect consequence of lowered Ub levels. Loss of Doa1 results in a defect in the accumulation of GFP-Ub within yeast vacuoles, implying that there is a reduction in the flux of ubiquitinated membrane proteins through the MVB pathway. This defect was also reflected by an inability to properly sort Vph1-GFP-Ub, a modified subunit of the multiprotein vacuolar ATPase complex, which carries an in-frame fusion of Ub as an MVB sorting signal. These results reveal novel roles for Doa1 in helping to process ubiquitinated membrane proteins for sorting into MVBs. 相似文献
76.
Wei Li Yuan-ying Shen Xuan-rong Zhang Lai-feng Ren Qiang Li Ru Shen Hai-ping Zhao 《中国病毒学》2008,23(1):57-62
To investigate the distribution of hepatitis B virus (HBV) genotypes and subgenotypes among the Bai nationality in Dali, a total of 100 serum samples from patients with chronic HBV-infection were collected for the detection of HBV genotypes and subgenotypes by genotype-specific primers and restriction fragment length polymorphism (RLFP), respectively. Among the 100 samples, the proportions of genotype B, C and mixed genotype (B C) were 41%, 25% and 34%, respectively. All the genotype B strains belonged to subgenotype Ba. In genotype C, 84% were Subgenotype Cs and 12% were subgenotype Ce. The distribution of genotypes B, C and B C showed no significant difference between male and female patients (P=0.182) and among the age groups of patients (P=0.812). The rates of HBeAg/HBeAg positivity were no significantly different among genotypes B, genotype C and mixed genotype (B C) (P=0.077/P=0.663). In Dali, genotypes B, B C and C existed among Bai nationality with chronic HBV-infection, and genotype B was the major genotype. Subgenotypes Ba and Cs were the predominant strains in patients with HBV genotype B/C infection. The most prominent characteristic was the higher prevalent rate of mixed genotype (B C) in patients. 相似文献
77.
黄连木五倍子的生态研究与利用 总被引:1,自引:0,他引:1
一、产地自然概况黄连木五倍子最早发现于河南省南部信阳市郊贤山脚下(东经114°0′,,北纬32°10′)。该地为低山丘陵,海拔90一320m,南部紧连鸡公山厂傍依南湾水库和狮河。 相似文献
78.
Biftu T Feng D Ponpipom M Girotra N Liang GB Qian X Bugianesi R Simeone J Chang L Gurnett A Liberator P Dulski P Leavitt PS Crumley T Misura A Murphy T Rattray S Samaras S Tamas T Mathew J Brown C Thompson D Schmatz D Fisher M Wyvratt M 《Bioorganic & medicinal chemistry letters》2005,15(13):3296-3301
Several analogs of 2,3-diaryl pyrroles were synthesized and evaluated as inhibitors of Eimeria tenella cGMP-dependent protein kinase and in in vivo anticoccidial assays. A 4-fluorophenyl group enhances both in vitro and in vivo activities. The most potent analogs are the 5-(N-methyl, N-ethyl, and N-methylazetidine methyl) piperidyl derivatives 12, 23, and 34. These compounds have a broad spectrum of activity. Based on the in vivo efficacy and cost of synthesis, the N-ethyl analog 23 was chosen as a novel anticoccidial agent for a field trial. 相似文献
79.
Ren Liang Zhou Pengpeng Zhu Yuanmin Zhang Ruijiao Yu Longjiang 《Applied microbiology and biotechnology》2017,101(9):3769-3780
Applied Microbiology and Biotechnology - Eicosapentaenoic acid (EPA) is an essential polyunsaturated fatty acid for human beings. At present, the production of commercially available long-chain... 相似文献
80.
Aolin Jia Yan Ren Fengmei Gao Guihong Yin Jindong Liu Lu Guo Jizhou Zheng Zhonghu He Xianchun Xia 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2018,131(5):1063-1071