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31.
Dingpei Long Weijian Lu Zhanzhang Hao Zhonghuai Xiang Aichun Zhao 《Transgenic research》2016,25(6):795-811
Efficient and inducible recombinase-mediated DNA excision is an optimal technology for automatically deleting unwanted DNA sequences, including selection marker genes. However, this methodology has yet to be established in transgenic silkworms. To achieve efficient and inducible FLP recombinase-mediated DNA excision in transgenic silkworms, one transgenic target strain (TTS) containing an FRT-flanked silkworm cytoplasmic actin 3 gene promoter (A3)-enhanced green fluorescent protein (EGFP) expression cassette, as well as two different types of FLP recombinase expression helper strains were generated. Then, the FLP recombinase was introduced into the TTS silkworms by pre-blastoderm microinjection and sexual hybridization. Successful recombinase-mediated deletion of the A3-EGFP expression cassette was observed in the offspring of the TTS, and the excision efficiencies of the FLP expression vector and FLP mRNA pre-blastoderm microinjection were 2.38 and 13.3 %, respectively. The excision efficiencies resulting from hybridization between the TTS and the helper strain that contained a heat shock protein 70 (Hsp70)-FLP expression cassette ranged from 32.14 to 36.67 % after heat shock treatment, while the excision efficiencies resulting from hybridization between the TTS and the helper strain containing the A3-FLP expression cassette ranged from 97.01 to 100 %. These results demonstrate that the FLP/FRT system can be used to achieve highly efficient and inducible post-integration excision of unwanted DNA sequences in transgenic silkworms in vivo. Our present study will facilitate the development and application of the FLP/FRT system for the functional analysis of unknown genes, and establish the safety of transgenic technologies in the silkworm and other lepidopteran species. 相似文献
32.
双效表达载体的构建及其U6启动子的功能效率鉴定 总被引:1,自引:0,他引:1
利用pBudcE4.1双表达载体构建shRNA与蛋白共表达载体,为双效疫苗的研制提供新的研究思路.以含U6启动子的载体为模板,PCR扩增得到U6启动子,用其置换载体pBudcE4.1内的CMV启动子的核心部分构建shRNA与蛋白共表达载体.用干扰绿色荧光蛋白表达的方法鉴定重组载体中的U6启动子能否启动shRNA的表达.经PCR扩增、双酶切鉴定及DNA测序证明成功构建了载体pBudcE4.1-U6.用干扰载体pBudcE4.1-U6-eGFPshRNA与含eGFP的载体共转染293T细胞后,荧光显微镜观察显示eGFP的表达量下降;流式细胞仪检测细胞的转染效率降低.研究结果证明U6启动子正常发挥作用. 成功构建RNAi与蛋白共表达载体,为利用该载体研制动物双效疫苗奠定了基础. 相似文献
33.
以广西弄岗北热带喀斯特季节性雨林15 hm2森林动态监测样地为对象,结合2011年和2016年两次调查数据,分析5年间样地树木死亡个体的数量、径级结构和空间格局特征等。结果显示:2011年至2016年,样地有86.5%的树种出现了个体死亡的现象,死亡个体占个体总数的14.4%;死亡个体的聚集程度随空间尺度的增大而逐渐减弱;小径级个体死亡与周边邻体和环境的关联性较大;竞争是影响弄岗北热带喀斯特季节性云林树木死亡的主要因素。综合来看,北热带喀斯特季节性雨林内树木死亡并非是一个完全随机的过程,而是树木本身特征和生物与非生物环境共同作用的结果。 相似文献
34.
35.
Hui Liu Xiang Li Matthew D. Dun Sam Faulkner Chen Chen Jiang Hubert Hondermarck 《Proteomics》2020,20(10)
Pancreatic cancer has a dismal prognosis and to date there are no targeted therapies for this malignancy. Using shotgun proteomics, the mRNA binding protein cold shock domain containing E1 (CSDE1), also called upstream‐of‐N‐Ras, is detected in pancreatic cancer cell lines but not in normal pancreatic epithelial cells. The expression of CSDE1 in pancreatic cancer cells is confirmed by Western blotting and immunohistochemistry of human pancreatic tumors. In vitro functional assays show that siRNA downregulation of CSDE1 or gene knockout using CRISPR‐Cas9 significantly reduce the invasiveness of pancreatic cancer cells. Together, this study reveals that CSDE1 is overexpressed in pancreatic cancer and is a potential therapeutic target to inhibit pancreatic cancer cell invasion. 相似文献
36.
Li‐Juan Wang Lin He Lu Hao Hong‐Lei Guo Xiang‐Peng Zeng Ya‐Wei Bi Guo‐Tao Lu Zhao‐Shen Li Liang‐Hao Hu 《Journal of cellular and molecular medicine》2020,24(17):9667-9681
Chronic pancreatitis (CP) is characterized by persistent inflammation of the pancreas that results in progressive loss of the endocrine and exocrine compartment owing to atrophy and/or replacement with fibrotic tissue. Currently, the clinical therapeutic scheme of CP is mainly symptomatic treatment including pancreatic enzyme replacement, glycaemic control and nutritional support therapy, lacking of specific therapeutic drugs for prevention and suppression of inflammation and fibrosis aggravating in CP. Here, we investigated the effect of isoliquiritigenin (ILG), a chalcone‐type dietary compound derived from licorice, on pancreatic fibrosis and inflammation in a model of caerulein‐induced murine CP, and the results indicated that ILG notably alleviated pancreatic fibrosis and infiltration of macrophages. Further in vitro studies in human pancreatic stellate cells (hPSCs) showed that ILG exerted significant inhibition on the proliferation and activation of hPSCs, which may be due to negative regulation of the ERK1/2 and JNK1/2 activities. Moreover, ILG significantly restrained the M1 polarization of macrophages (RAW 264.7) via attenuation of the NF‐κB signalling pathway, whereas the M2 polarization was hardly affected. These findings indicated that ILG might be a potential anti‐inflammatory and anti‐fibrotic therapeutic agent for CP. 相似文献
37.
Bairen Yang Ke Du Chuanhua Yang Lili Xiang Ying Xu Chen Cao Junhui Zhang Wenneng Liu 《Journal of cellular and molecular medicine》2020,24(6):3431-3437
CircPRTM5 is associated with cell proliferation and migration in many kinds of malignancies. However, the functions and mechanisms of CircPRTM5 in CRC progression remain unclear. We explored the role and the mechanisms of CircPRTM5 in the development of CRC. Tissues of CRC patients and matched adjacent non-tumour tissues were collected to evaluate the expression of CircPRTM5. The expression of CircPRTM5 in CRC tissues was significantly higher than that in adjacent tissues. The biological functions of CircPRTM5 in CRC were determined by overexpression and down-regulation of CircPRTM5 in CRC cells in vitro and in vivo. The results indicate that knockdown of CircPRTM5 can significantly inhibit the proliferation of CRC cells. The potential mechanisms of CircPRTM5 in CRC development were identified by RT-qPCR, Western blotting analysis and luciferase reporter assay. CircPRTM5 competitively regulates the expression of E2F3 by capillary adsorption of miR-377. CircPRMT5 regulates CRC proliferation by regulating the expression of E2F3, which affects the expression of the cell cycle-associated proteins cyclinD1 and CDK2. CircPRTM5 exerts critical regulatory role in CRC progression by sponging miR-377 to induce E2F3 expression. 相似文献
38.
Jialing Rong Xianqun Xu Yang Xiang Guohua Yang Xinliang Ming Siying He Bin Liang Xiaokang Zhang Fang Zheng 《Journal of cellular and molecular medicine》2020,24(6):3560-3571
Numerous studies have demonstrated that thioredoxin-interacting protein (TXNIP) expression of peripheral blood leucocytes is increased in coronary artery disease (CAD). However, the molecular mechanism of this phenomenon remained unclear. DNA methylation plays important roles in the regulation of gene expression. Therefore, we speculated there might be a close association between the expression of TXNIP and methylation. In this study, we found that compared with controls, DNA methylation at cg19693031 was decreased in CAD, while mRNA expressions of TXNIP and inflammatory factors, NLRP3, IL-1β, IL-18, were increased. Methylation at cg19693031 was negatively associated with TXNIP expression in the cohort, THP-1 and macrophages/foam cells. Furthermore, Transwell assay and co-cultured adhesion assay were performed to investigate functions of TXNIP on the migration of THP-1 or the adhesion of THP-1 on the surface of endothelial cells, respectively. Notably, overexpressed TXNIP promoted the migration and adhesion of THP-1 cells and expressions of NLRP3, IL-18 and IL-1β. Oppositely, knock-down TXNIP inhibited the migration and adhesion of THP-1 and expressions of NLRP3, IL-18. In conclusion, increased TXNIP expression, related to cg19693031 demethylation orientates monocytes towards an inflammatory status through the NLRP3 inflammasome pathway involved in the development of CAD. 相似文献
39.
40.
Ba Limin Wang Zhenbao Liu William J Wu Dongxun Xiang Wangzhen Qi Peng Dong Chunna Hu Yanxin Lu Ping Xiao Jin Yu Changyuan 《中国科学:生命科学英文版》2020,63(10):1604-1607
正Dear Editor,Swine major histocompatibility complex (MHC) is a highly polymorphic gene in pigs and is also called swine leukocyte antigen (SLA)(Fan et al., 2018). SLA is divided into three major categories, SLA Ⅰ (SLA-1,-2,-3), SLA Ⅱ, and SLA Ⅲ(Smith et al., 2005). SLA Ⅰ plays an important role in cellular immunity which can eliminate viruses and other foreign 相似文献