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pGL3-Basic-COX-2-promoter报告基因重组质粒的构建及其功能鉴定 被引量:3
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作者 李琦 周利红 +3 位作者 王炎 孙珏 高虹 范忠泽 《世界华人消化杂志》 CAS 北大核心 2008年第31期3498-3504,共7页
目的:构建COX-2基因启动子荧光素酶报告基因重组质粒pGL3-Basic-COX-2-promoter,并进行功能鉴定.方法:根据已知人的COX-2基因启动子序列设计两端引物,扩增人基因组DNA中的COX-2启动子.载体质粒pGL3-Basic和COX-2启动子分别用限制性内切... 目的:构建COX-2基因启动子荧光素酶报告基因重组质粒pGL3-Basic-COX-2-promoter,并进行功能鉴定.方法:根据已知人的COX-2基因启动子序列设计两端引物,扩增人基因组DNA中的COX-2启动子.载体质粒pGL3-Basic和COX-2启动子分别用限制性内切酶HindⅢ和BglⅡ双酶切,将COX-2基因启动子插入到pGL3-Basic报告载体中.构建的pGL3-Basic-COX-2-promoter重组质粒和内参质粒pRL-SV40瞬时共转染胃癌MKN45细胞,加入100倍细胞数量的Hpylori共培养不同时间后,检测双荧光素酶的活性.结果:成功构建COX-2基因启动子重组质粒pGL3-Basic-COX-2-promoter,质粒测序及酶切结果完全正确.瞬时转染实验显示,COX-2启动子在MKN45细胞中的转录表达随时间的变化而升高,转染后40h的双报告基因活性是转染后8h的3.5倍(P<0.01);加入Hpylori共培养后,同时间点的荧光素酶活性明显升高(P<0.05或0.01),转染后40h的活性是转染后8h的5倍(P<0.01).结论:pGL3-Basic-COX-2-promoter在胃癌MKN45细胞中能被转录激活,加入Hpylori刺激后COX-2活性显著增强,pGL3-Basic-COX-2-promoter可以用来鉴定和检测细胞中COX-2的水平. 展开更多
关键词 环氧合酶2 启动子 质粒 幽门螺杆菌 双荧光素酶
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Cdx2 expression and its promoter methylation during metaplasia-dysplasia-carcinoma sequence in Barrett's esophagus 被引量:5
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作者 Kenji Makita Riko Kitazawa +4 位作者 Shuho Semba Koto Fujiishi Miku Nakagawa Ryuma Haraguchi Sohei Kitazawa 《World Journal of Gastroenterology》 SCIE CAS 2013年第4期536-541,共6页
AIM:To examine how the expression of caudal type homebox transcription factor 2(Cdx2) is regulated in the development of malignancy in Barrett's esophagus.METHODS:Cdx2,mucin(MUC) series(MUC2,MUC5AC and MUC6),p53 a... AIM:To examine how the expression of caudal type homebox transcription factor 2(Cdx2) is regulated in the development of malignancy in Barrett's esophagus.METHODS:Cdx2,mucin(MUC) series(MUC2,MUC5AC and MUC6),p53 and E-cadherin expression in Barrett's esophagus and adenocarcinoma specimens were examined by immunostaining.Isolated clusters of cells from(1) MUC2 and Cdx2-positive intestinal metaplastic mucosa;(2) MUC5AC and MUC6-positive,and MUC2 and Cdx2-negative high-grade dysplasia(HD),or intramucosal adenocarcinoma(IMC);and(3) MUC5AC,MUC6 and Cdx2-positive poorly-differentiated invasive adenocarcinoma(PDA) were analyzed by methylationspecific polymerase chain reaction using sets of primers for detecting methylation status of the Cdx2 gene.RESULTS:Most of the non-neoplastic Barrett's esophageal mucosa showing intestinal-type metaplasia with or without low-grade dysplasia was positive for E-cadherin,MUC series and Cdx2,but negative for p53.A portion of the low-grade to HD was positive for E-cadherin,MUC5AC,MUC6 and p53,but negative for MUC2 and Cdx2.The definite IMC area was strongly positive for MUC5AC,MUC6 and p53,but negative for MUC2 and Cdx2.Methylation of the Cdx2 promoter was not observed in intestinal metaplasia,while hypermethylation of part of its promoter was observed in hot dipped and IMC.Hypermethylation of a large fraction of the Cdx2 promoter was observed in PDA.CONCLUSION:Cdx2 expression is restored irrespective of the methylation status of its promoter.Apparent positive immunohistochemical results can be a molecular mark for gene silencing memory. 展开更多
关键词 BARRETT ’s ESOPHAGUS CAUDAL type homebox transcription factor 2 Intestinal METAPLASIA promoter HYPERMETHYLATION
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Sp1 contributes to overexpression of stanniocalcin 2 through regulation of promoter activity in colon adenocarcinoma 被引量:3
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作者 Ji-Bin Li Zhe-Xian Liu +6 位作者 Rui Zhang Si-Ping Ma Tao Lin Yan-Xi Li Shi-Hua Yang Wan-Chuan Zhang Yong-Peng Wang 《World Journal of Gastroenterology》 SCIE CAS 2019年第22期2776-2787,共12页
BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the ... BACKGROUND Aberrant expression of stanniocalcin 2 (STC2) is implicated in colon adenocarcinoma (COAD). A previous study identified that STC2 functions as a tumor promoter to drive development of some cancers, but the role of its overexpression in the development of COAD remains unclear. AIM To evaluate the regulation mechanism of STC2 overexpression in COAD. METHODS The expression of STC2 in COAD was assessed by TCGA COAD database and GEO (GSE50760). Methylation level of the STC2 promoter was evaluated with beta value in UALCAN platform, and the correlation between STC2 expression and survival rate was investigated with TCGA COAD. Transcription binding site prediction was conducted by TRANSFAC and LASAGNA, and a luciferase reporter system was used to identify STC2 promoter activity in several cell lines, including HEK293T, NCM460, HT29, SW480, and HCT116. Western blotting was performed to evaluate the role of Sp1 on the expression of STC2. RESULTS The central finding of this work is that STC2 is overexpressed in COAD tissues and positively correlated with poor prognosis. Importantly, the binding site of the transcription factor Sp1 is widely located in the promoter region of STC2. A luciferase reporter system was successfully constructed to analyze the transcription activity of STC2, and knocking down the expression of Sp1 significantly inhibited the transcription activity of STC2. Furthermore, inhibition of Sp1 remarkably decreased protein levels of STC2. CONCLUSION Our data provide evidence that the transcription factor Sp1 is essential for the overexpression of STC2 in COAD through activation of promoter activity. Taken together, our finding provides new insights into the mechanism of oncogenic function of COAD by STC2. 展开更多
关键词 Transcription factor SP1 STANNIOCALCIN 2 OVEREXPRESSION promoter activity COLON ADENOCARCINOMA
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Effects of Potassium and Manganese Promoters on Nitrogen-Doped Carbon Nanotube-Supported Iron Catalysts for CO_2 Hydrogenation 被引量:6
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作者 Praewpilin Kangvansura Ly May Chew +6 位作者 Chanapa Kongmark Phatchada Santawaja Holger Ruland Wei Xia Hans Schulz Attera Worayingyong Martin Muhler 《Engineering》 SCIE EI 2017年第3期385-392,共8页
Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted ... Nitrogen-doped carbon nanotubes (NCNTs) were used as a support for iron (Fe) nanoparticles applied in car- bon dioxide (CO_2) hydrogenation at 633 K and 25 bar (1 bar = 10-5 Pa). The Fe/NCNT catalyst promoted with both potassium (K) and manganese (Mn) showed high performance in CO_2 hydrogenation, reaching 34.9% conversion with a gas hourly space velocity (GHSV) of 3.1 L-(g·h)-1. Product selectivities were high for olefin products and low for short-chain alkanes for the K-promoted catalysts. When Fe/NCNT catalyst was promot- ed with both K and Mn, the catalytic activity was stable for 60 h of reaction time. The structural effect of the Mn promoter was demonstrated by X-ray diffraction (XRD), temperature-programmed reduction (TPR) with molecular hydrogen (H2), and in situ X-ray absorption near-edge structure (XANES) analysis. The Mn pro- moter stabilized wtistite (FeO) as an intermediate and lowered the TPR onset temperature. Catalytic ammo- nia (NH_3) decomposition was used as an additional probe reaction for characterizing the promoter effects. The Fe/NCNT catalyst promoted with both K and Mn had the highest catalytic activity, and the Mn-promoted Fe/NCNT catalysts had the highest thermal stability under reducing conditions. 展开更多
关键词 CO_2 hydrogenation Iron catalyst Nitrogen-doped carbon nanotubes Manganese promoter Potassium promoter
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Promoter methylation status of hMLH1,MGMT,and CDKN2A/p16 in colorectal adenomas 被引量:14
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作者 Vasiliki Psofaki Chryssoula Kalogera +4 位作者 Nikolaos Tzambouras Dimitrios Stephanou Epameinondas Tsianos Konstantin Seferiadis Georgios Kolios 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第28期3553-3560,共8页
AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma... AIM:To investigate aberrant DNA methylation of CpG islands and subsequent low-or high-level DNA microsatellite instability(MSI)which is assumed to drive colon carcinogenesis. METHODS:DNA of healthy individuals,adenoma(tu-bular or villous/tubulovillous)patients,and colorectal carcinoma patients who underwent colonoscopy was used for assessing the prevalence of aberrant DNA methylation of human DNA mismatch repair gene mutator L homologue 1(hMLH1),Cyclin-dependent kinase inhibitor 2A(CDKN2A/p16),and O-6-methylguanine DNA methyltransferase(MGMT),as well as their rela- tion to MSI. RESULTS:The frequency of promoter methylation for each locus increased in the sequence healthy tissue/adenoma/carcinoma.MGMT showed the highest frequency in each group.MGMT and CDKN2A/p16 presented a statistically significant increase in promoter methylation between the less and more tumorigenic forms of colorectal adenomas(tubular vs tubullovillous and villous adenomas).All patients with tubulovillous/villous adenomas,as well as all colorectal cancer patients,showed promoter methylation in at least one of the examined loci.These findings suggest a potentially crucial role for methylation in the polyp/adenoma to cancer progres- sion in colorectal carcinogenesis.MSI and methylation seem to be interdependent,as simultaneous hMLH1, CDKN2A/p16,and MGMT promoter methylation was present in 8/9 colorectal cancer patients showing the MSI phenotype. CONCLUSION:Methylation analysis of hMLH1,CD- KN2A/p16,and MGMT revealed specific methylation profiles for tubular adenomas,tubulovillous/villous adenomas,and colorectal cancers,supporting the use of these alterations in assessment of colorectal tumorigenesis. 展开更多
关键词 promoter methylation Microsatellite instability Human DNA mismatch repair gene mutator L homologue 1 O-6-methylguanine DNA methyltransferase Cyclin-dependent kinase inhibitor 2A
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A novel SATB1 binding site in the BCL2 promoter region possesses transcriptional regulatory function 被引量:3
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作者 Feiran Gong 《The Journal of Biomedical Research》 CAS 2010年第6期452-459,共8页
BCL2 is a key regulator of apoptosis.Our previous work has demonstrated that special AT-rich sequence-binding protein 1 (SATB1) is positively correlated with BCL2 expression.In the present study,we report a new SATB... BCL2 is a key regulator of apoptosis.Our previous work has demonstrated that special AT-rich sequence-binding protein 1 (SATB1) is positively correlated with BCL2 expression.In the present study,we report a new SATB1 binding site located between P1 and P2 promoters of the BCL2 gene.The candidate SATB1 binding sequence predicted by bioinformatic analysis was investigated in vitro and in vivo by electrophoretic gel mobility shift assays (EMSA) and chromatin immunoprecipitation (ChIP).One 25-bp sequence,named SB1,was confirmed to be SATB1 binding site.The regulatory function of SB1 and its relevance to SATB1 were further examed with dual-luciferase reporter assay system in Jurkat cells.We found that SB1 could negatively regulate reporter gene activity.Mutation of SATB1 binding site further repressed the activity.Knockdown of SATB1 also enhanced this negative effect of SB1.Our data indicate that the SB1 sequence possesses negative transcriptional regulatory function and this function can be antagonized by SATB1. 展开更多
关键词 BCL2 promoter special AT-rich sequence-binding protein 1 transcriptional regulation
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Insight into MgO promoter with low concentration for the carbon-deposition resistance of Ni-based catalysts in the CO_2 reforming of CH_4 被引量:4
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作者 Xiangdong Feng Jie Feng Wenying Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期88-98,共11页
The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction o... The CO2reforming of CH4is studied over MgO‐promoted Ni catalysts,which were supported on alumina prepared from hydrotalcite.This presents an improved stability compared with non‐promoted catalysts.The introduction of the MgO promoter was achieved through the‘‘memory effect’’of the Ni‐Al hydrotalcite structure,and ICP‐MS confirmed that only0.42wt.%of Mg2+ions were added into the Ni‐Mg/Al catalyst.Although no differences in the Ni particle size and basicity strength were observed,the Ni‐Mg/Al catalyst showed a higher catalytic stability than the Ni/Al catalyst.A series of surface reaction experiments were used and showed that the addition of a MgO promoter with low concentration can promote CO2dissociation to form active surface oxygen arising from the formation of the Ni‐MgO interface sites.Therefore,the carbon‐resistance promotion by nature was suggested to contribute to an oxidative environment around Ni particles,which would increase the conversion of carbon residues from CH4cracking to yield CO on the Ni metal surface.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 CO2 reforming of CH4 Carbon‐deposition resistant Activation of CO2 Ni‐based catalyst Low concentration MgO promoter
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Enhanced stability of Pt/Al_(2)O_(3) modified by Zn promoter for catalytic dehydrogenation of ethane 被引量:2
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作者 Xiaoyu Li Yanliang Zhou +6 位作者 Botao Qiao Xiaoli Pan Chaojie Wang Liru Cao Lin Li Jian Lin Xiaodong Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期14-20,共7页
Catalytic ethane dehydrogenation(EDH) to ethylene over Pt-based catalysts has received increasing interests in recent years as it is a potential alternative route to conventional steam cracking. However, the catalysts... Catalytic ethane dehydrogenation(EDH) to ethylene over Pt-based catalysts has received increasing interests in recent years as it is a potential alternative route to conventional steam cracking. However, the catalysts used in this reaction often suffer from rapid deactivation due to serious coke deposition and metal sintering. Herein, we reported the effects of Zn modification on the stability of Pt/Al2 O3 for EDH.The Zn-modified sample(PtZn2/Al2 O3) exhibits stable ethane conversion(20%) with over 95% ethylene selectivity. More importantly, it exhibits a significantly low deactivation rate of only 0.003 h-1 at 600 °C for70 h, which surpasses most of previously reported catalysts. Detailed characterizations including in situ FT-IR, ethylene adsorption microcalorimetry, and HAADF-STEM etc. reveal that Zn modifier reduces the number of Lewis acid sites on the catalyst surface. Moreover, it could modify Pt sites and preferentially cover the step sites, which decrease surface energy and retard the sintering of Pt particle, then prohibiting the further dehydrogenation of ethylene to ethylidyne. Consequently, the good stability is realized due to anti-sintering and the decrease of coke formation on the Pt Zn2/Al2 O3 catalyst. 展开更多
关键词 Catalytic dehydrogenation of ethane STABILITY PtZn/Al2O3 Zn promoter COKE
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Revealing the Promoting Eff ect of CeO_(2)on the Cu/ZnO Catalyst for Methanol Steam Reforming
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作者 Mengyuan Zhu Didi Li +5 位作者 Zhaocong Jiang Shiqing Jin Qing Zhang Haoyuan Gu Yi-Fan Han Minghui Zhu 《Transactions of Tianjin University》 EI CAS 2024年第6期544-552,共9页
Cu-based catalysts have been extensively used in methanol steam reforming(MSR)reactions because of their low cost and high effi ciency.ZnO is often used in commercial Cu-based catalysts as both a structural and an ele... Cu-based catalysts have been extensively used in methanol steam reforming(MSR)reactions because of their low cost and high effi ciency.ZnO is often used in commercial Cu-based catalysts as both a structural and an electronic promoter to stabilize metal Cu nanoparticles and modify metal–support interfaces.Still,the further addition of chemical promoters is essential to further enhance the MSR reaction performance of the Cu/ZnO catalyst.In this work,CeO_(2)-doped Cu/ZnO catalysts were prepared using the coprecipitation method,and the eff ects of CeO_(2)on Cu-based catalysts were systematically investigated.Doping with appropriate CeO_(2)amounts could stabilize small Cu nanoparticles through a strong interaction between CeO_(2)and Cu,leading to the formation of more Cu+–ZnO x interfacial sites.However,higher CeO_(2)contents resulted in the formation of larger Cu nanoparticles and an excess of Cu+–CeO x interfacial sites.Consequently,the Cu/5CeO_(2)/ZnO catalyst with maximal Cu–ZnO interfaces exhibited the highest H 2 production rate of 94.6 mmolH2/(gcat·h),which was 1.5 and 10.2 times higher than those of Cu/ZnO and Cu/CeO_(2),respectively. 展开更多
关键词 Methanol steam reforming Cu/ZnO catalyst CeO_(2)promoter Metal–support interaction Interfacial site
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Methylation of hMLH1 and hMSH2 promoters in gastric carcinomas 被引量:1
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作者 房殿春 罗元辉 《Journal of Medical Colleges of PLA(China)》 CAS 2002年第2期143-146,共4页
Objective: To study the correlation of the methylation of the promoters of hMLH1 and hMSH2 with microsatellite instability (MSI) in the tissues of gastric carcinomas. Methods: A total of 68 sporadic cases of gastric c... Objective: To study the correlation of the methylation of the promoters of hMLH1 and hMSH2 with microsatellite instability (MSI) in the tissues of gastric carcinomas. Methods: A total of 68 sporadic cases of gastric carcinoma were studied. Ten specimens of normal gastric mucosa served as control. Methylation of hMLHl and hMSH2 was observed with methylation-specific PCR, and MSI analyzed with PCR-based techniques. Results: No methylation of hMLHl and hMSH2 was found in 10 specimens of normal gastric mucosa. Methylation of hMLHl was detected in 11 cases (16. 2%) of gastric cancers and MSI in at least one locus was found in 17 cases (25%) of the 68 with aid of 5 microsatellite markers, in which eight were MSI-H (≥2loci showed instability) nine MSI-L (only one locus showed instability), and fifty-one were MSS (no instability at any marker). The frequency of methylation was significantly high in MSI-H (87. 5%) than in MSI-L (11.1%) and MSS (5. 9%). CP<0. 01 - 0. 001) but there was no difference of methylation frequency between the cases with MSI-L and those with MSS. Conclusion: Methylation of hMLHl promoter is involved to the MSI pathway but not to the loss of heterozygosity (LOH) pathway in gastric carcinogenesis. 展开更多
关键词 gastric carcinoma METHYLATION promoter of hMLH1 promoter of hMSH2 microsatellite instability
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Cloning the Promoter of BcNA1 from Brassica napus and Fad2 Gene from Arabidopsis thaliana and Construction of the Plant Expression Vector 被引量:1
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作者 石东乔 《High Technology Letters》 EI CAS 2000年第1期83-90,共8页
The upstream regulatory region of a seed specific gene was isolated from the genomic DNA of Brassica napus by PCR amplification. The cloned fragment contained 1755 nucleotides, and shared a sequence homology of 99.6%... The upstream regulatory region of a seed specific gene was isolated from the genomic DNA of Brassica napus by PCR amplification. The cloned fragment contained 1755 nucleotides, and shared a sequence homology of 99.6% with the reported data. The coding region of oleic acid desaturase gene was then cloned from Arabidopsis thaliana. The sequencing analysis indicated that the sequence of the PCR product was just the same as reported before. In addition, the plant expression vector harboring the seed specific promoter and trans Fad2 gene was constructed. 展开更多
关键词 BRASSICA NAPUS Arabidopsis THALIANA seed specific promoter FAD2 gene plant expression vector
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Cloning and characterization of an apolipoprotein C2 promoter in the mouse central nervous system 被引量:1
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作者 Zhaoyang Li Bing Du +5 位作者 Shengyang Li Xiangchuan Lv Shenglai Zhou Yang Yu Wei Wang Zhihong Zheng 《Neural Regeneration Research》 SCIE CAS CSCD 2013年第2期156-161,共6页
Apolipoprotein C2 is an important member of the apolipoprotein C family, and is a potent activator of lipoprotein lipase. In the central nervous system, apolipoprotein C2 plays an important role in the catabolism of t... Apolipoprotein C2 is an important member of the apolipoprotein C family, and is a potent activator of lipoprotein lipase. In the central nervous system, apolipoprotein C2 plays an important role in the catabolism of triglyceride-rich lipoproteins. Studies into the exact regulatory mechanism of mouse apolipoprotein C2 expression have not been reported. In this study, seven luciferase expression vectors, which contained potential mouse apolipoprotein C2 gene promoters, were constructed and co-transfected with pRL-TK into HEK293T cells to investigate apolipoprotein C2 promoter activity. Luciferase assays indicated that the apolipoprotein C2 promoter region was mainly located in the +104 bp to +470 bp region. The activity of the different lengths of apolipoprotein C2 promoter region varied. This staggered negative-positive-negative arrangement indicates the complex regulation of apolipoprotein C2 expression and provides important clues for elucidating the regulatory mechanism of apolipoprotein C2 gene transcription. 展开更多
关键词 neural regeneration basic research apolipoprotein C2 promoter dual-luciferase reporter assay transcriptional activity regulatory elements grants-supported paper NEUROREGENERATION
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Elucidating the effect of barium halide promoters on La_(2)O_(3)/CaO catalyst for oxidative coupling of methane 被引量:1
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作者 Yue Wang Xiao Yang +6 位作者 Fumin Yin Kai Zhang Hongfei Guo Guowei Wang Guiyuan Jiang Chunyi Li Xiaolin Zhu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期49-59,I0003,共12页
The industrialization of oxidative coupling of methane(OCM)is restricted by the low once through yield of C_(2)hydrocarbons.Recently,the halogen-assisted OCM process has been attempted to overcome this issue,but the r... The industrialization of oxidative coupling of methane(OCM)is restricted by the low once through yield of C_(2)hydrocarbons.Recently,the halogen-assisted OCM process has been attempted to overcome this issue,but the reaction stability was poor due to the rapid loss of gas-phase halides or molten alkali halides.In this work,the barium salts,particularly barium halides(BaCl_(2)and BaF_(2)),were demonstrated to be efficient promoters to improve the OCM reactivity of La_(2)O_(3)/CaO catalyst by increasing both C_(2)selectivity and C_(2)H_(4)/C_(2)H_(6)ratio,and simultaneously achieving outstanding reaction stability.The promoting mechanism can be understood in two aspects.On the one hand,the introduction of barium salts increased the amount of surface electrophilic oxygen species,serving as the alkaline active sites for selective methane activation.On the other hand,the barium halide additives induced the in-situ formation of methyl halide intermediates facilitating C_(2)H_(6)dehydrogenation,and their intimate contact with catalyst substrate restricted the rapid halogen loss and thereby improved the catalytic stability.This work not only provides a class of efficient OCM catalyst,but also offers a highly stable halogen-assisted reaction strategy. 展开更多
关键词 Oxidative coupling of methane La_(2)O_(3)/CaO catalyst Barium halide promoters Active oxygen species Methyl halide intermediates
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Hepatitis B virus X protein regulates the mEZH2 promoter via the E2F1-binding site in AML12 cells 被引量:1
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作者 Xiao-Yan Shi Ying-Ying Zhang +3 位作者 Xiao-Wei Zhou Jian-Sheng Lu Ze-Kun Guo Pei-Tang Huang 《Chinese Journal of Cancer》 SCIE CAS CSCD 北大核心 2011年第4期273-279,共7页
Histone lysine methyltransferase EZH2 has been reported to be frequently overexpressed in hepatocellular carcinoma(HCC) tissues and associated with hepatocarcinogenesis.However,the exact mechanism of EZH2 up-regulatio... Histone lysine methyltransferase EZH2 has been reported to be frequently overexpressed in hepatocellular carcinoma(HCC) tissues and associated with hepatocarcinogenesis.However,the exact mechanism of EZH2 up-regulation in HCC has not been determined.In this study,we used murine hepatocyte AML12 cells to investigate the role of hepatitis B virus X protein(HBx) in regulating the expression of mEZH2.Western blot analysis demonstrated that the expression level of mEZH2 protein in AML12 cells was up-regulated by HBx in a dose-dependent manner.To further investigate the mechanism of mEZH2 overexpression,the 2500 bp regulatory sequence upstream from the first exon of the mEZH2 gene was amplified from AML12 genomic DNA and constructed into a luciferase reporter plasmid.The luciferase activity of the mEZH2 promoter significantly increased in AML12 cells co-transfected with HBx plasmid,and deleting the-486/-214 promoter region decreased HBx-induced mEZH2 promoter activation by nearly 50%.The-486/-214 region was then analyzed in the TRANSFAC 6.0 database and a typical E2F1-binding site was found.Mutation of this E2F1-binding site or knockdown of E2F1 expression by RNAi led to a dramatic decrease in HBx-induced activation of the mEZH2 promoter and mEZH2 overexpression in AML12 cells.These results provide evidence that HBx up-regulates mEZH2 expression by transactivating the mEZH2 promoter through E2F1 transcription factor,thereby providing new epigenetic evidence for the carcinogenic effect of HBx. 展开更多
关键词 乙型肝炎病毒 肝细胞癌 结合位点 组蛋白 启动子 BLOT分析 过度表达 质粒构建
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Evaluation of Uncertainty in Measuring the Content of CaM V35S Promoter in Genetically Modified Soybean,GTS40-3-2,by Real-time Quantitative PCR
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作者 Dong WANG Jun SONG +5 位作者 Ling'an GUO Shaorong LEI Wenjuan LIU Lijuan CHANG Quan YIN Fuli ZHANG 《Agricultural Biotechnology》 CAS 2015年第1期23-26,30,共5页
[ Objective ] This study aimed to investigate the major contributors to the measurement uncertainty in quantitative analysis of genetically modified ingreclients and improve the quality of quantitative detection of ge... [ Objective ] This study aimed to investigate the major contributors to the measurement uncertainty in quantitative analysis of genetically modified ingreclients and improve the quality of quantitative detection of genetically modified components. [ Method] The content of CaMV35S promoter (parameter) in GTS40- 3-2 soybean powder samples was measured to estimate the measurement uncertainty preliminarily. [ Result] Type A uncertainty (uA) ' type B uncertainty (uB) and combined standard uncertainty (Uc) were 0.0 004, 0.002 and 0.002, respectively. At a confidence level ofp = 95% and freedom degree of Voff = 3 251, coverage factor k = 1.96, expanded uncertainty U = 0.004. The final measurement result was C = 0.028 ± 0. 004, which was dose to the conventional true value (0.03). Thus, the measurement uncertainty was relatively small, indicating a high quality of measurement. In this study, uncertainty evaluation indicated that the deviation of micro liquid transfer made the greatest contribution to the measurement uncertainty. [ Cludusion ] The deviation of micro liquid transfer should be reduced to im- prove the quality of measurement. 展开更多
关键词 Genetically modified soybean GTS40-3 -2 Content of CaM-V35S promoter UNCERTAINTY EVALUATION
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Analysis on Cloning and Expression of Promoter of Flowering Time GmFT2a in Soybean
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作者 Liu Tian-meng Li Xin +3 位作者 Wang Qi Fan Yu-huan Liu Zheng-ya Zhao Lin 《Journal of Northeast Agricultural University(English Edition)》 CAS 2022年第1期1-8,共8页
Soybean(Glycine max)is short-day(SD)plant.Flowering time is a key agronomic trait that determines the transition from vegetative to reproductive growth.The study on the expression and regulation mechanism of flowering... Soybean(Glycine max)is short-day(SD)plant.Flowering time is a key agronomic trait that determines the transition from vegetative to reproductive growth.The study on the expression and regulation mechanism of flowering time gene in soybean photoperiod control of flowering pathway is particularly theoretically significant for soybean genetic improvement.In this study,a dual-luciferase reporter gene system with the GmFT2a gene promoter as promoter sequence was constructed,and the method of Agrobacterium tumefaciens injection into tobacco leaves was selected to study the effects of long and short days on the activity of the GmFT2a gene promoter.The results of transient expression analysis showed that the GmFT2a promoter was strongly induced under the SD conditions in tobacco.Furthermore,analysis of the GmFT2a promoter sequence revealed several cis-acting elements,including G-Box,Box 4,GT1-motif and TCT-motif by PlantCARE search.It was speculated that these elements might promote the expression of GmFT2a gene in the SDs and played a role in promoting flowering.The results of this study provided a basis for a better understanding of the function of the GmFT2a gene and further exploration of the complex flowering mechanism of soybean. 展开更多
关键词 SOYBEAN promoter GmFT2a light-induced response element PHOTOPERIOD
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Preparation of Nanoporous Carbonaceous Promoters for Enhanced CO2 Absorption in Tertiary Amines
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作者 Masood S.Alivand Omid Mazaheri +3 位作者 Yue Wu Geoffrey W.Stevens Colin A.Scholes Kathryn A.Mumford 《Engineering》 SCIE EI 2020年第12期1381-1394,共14页
Aqueous solutions of tertiary amines are promising absorbents for CO2 capture,as they are typically characterized by a high absorption capacity,low heat of reaction,and low corrosivity.However,tertiary amines also exh... Aqueous solutions of tertiary amines are promising absorbents for CO2 capture,as they are typically characterized by a high absorption capacity,low heat of reaction,and low corrosivity.However,tertiary amines also exhibit very low kinetics of CO2 absorption,which has made them unattractive options for large-scale utilization.Here,a series of novel nanoporous carbonaceous promoters(NCPs)with different properties were synthesized,characterized,and used as rate promoters for CO2 absorption in aqueous N,N-diethylethanolamine(DEEA)solutions.To prepare a DEEA–NCP nanofluid,NCPs were dispersed into aqueous 3 mol∙L1 DEEA solution using ultrasonication.The results revealed that among microporous(GC)and mesoporous(GS)carbonaceous structures functionalized with ethylenediamine(EDA)and polyethyleneimine(PEI)molecules,the GC–EDA promoter exhibited the best performance.A comparison between DEEA–GC–EDA nanofluid and typical aqueous DEEA solutions highlighted that the GC-EDA promoter enhances the rate of CO2 absorption at 40C by 38.6%(36.8–50.7 kPamin1)and improves the equilibrium CO2 absorption capacity(15 kPa;40C)by 13.2%(0.69–0.78 mol of CO2 per mole of DEEA).Moreover,the recyclability of DEEA–GC–EDA nanofluid was determined and a promotion mechanism is suggested.The outcomes demonstrate that NCP–GC–EDA in tertiary amines is a promising strategy to enhance the rate of CO2 absorption and facilitate their large-scale deployment. 展开更多
关键词 CO2 absorption NANOFLUID N N-diethylethanolamine Nanoporous carbonaceous promoters Polyamine functionalization
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Specific activation of 2'-5'oligoadenylate synthetase gene promoter by hepatitis C virus-core protein:A potential for developing hepatitis C virus targeting gene therapy
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作者 Ying Wang Shan-Shan Mao +3 位作者 Qiong-Qiong He Yuan Zi Ji-Fang Wen De-Yun Feng 《World Journal of Gastroenterology》 SCIE CAS CSCD 2009年第25期3178-3182,共5页
AIM: TO examine whether 2'-5'oligoadenylate synthetase (OAS) gene promoter can be specifically activated by hepatitis C virus (HCV)-core protein. METHODS: Human embryo hepatic cell line L02 was transfected wit... AIM: TO examine whether 2'-5'oligoadenylate synthetase (OAS) gene promoter can be specifically activated by hepatitis C virus (HCV)-core protein. METHODS: Human embryo hepatic cell line L02 was transfected with pcDNA3.1-core plasmid and selected by G418. Expression of HCV-core was detected by reverse transcription polymerase chain reaction and Western blotting. The OAS promoter sequence was amplified from the genomic DNA and inserted into pGL3-basic vector. The resultant pGL3-OAS-Luci plasmid was transiently transfected into L02/core cells and luciferase activity was assayed. I^ESULTS: L02/core cell line stably expressing HCV- core protein was established. The pGL3-OAS-Luci construct exhibited significant transcriptional activity in the L02/core cells but not in the L02 cells. CONCLUSION: HCV-core protein activates the OAS gene promoter specifically and effectively. Utilization of OAS gene promoter would be an ideal strategy for developing HCV-specific gene therapy. 展开更多
关键词 Hepatitis C virus Gene promoter Gene therapy CORE 2'-5'oligoadenylate synthetase
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A stage-specific protein factor binding to a CACCC motif in both human β-globin gene promoter and 5'-HS2region
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作者 SUN TONG- YADI CHEN YULONG HU +1 位作者 CHANGHONGDAI RUOLAN QIAN.(Shanghai Institute of Cell Biology, Academia Sinica,Shanghai 200031- China) 《Cell Research》 SCIE CAS CSCD 1994年第2期135-143,共9页
The DNasel hypersensitive site 2 (HS2) of human β-globin locus control region (LCR) is required fOr the high level expression of human d-globin genes. In the present study, a stage-specific protein factor (LPF-β) wa... The DNasel hypersensitive site 2 (HS2) of human β-globin locus control region (LCR) is required fOr the high level expression of human d-globin genes. In the present study, a stage-specific protein factor (LPF-β) was identified in the nuclear extract prepared from mouse fetal liver at d 18 of gestation, which could bind to the HS2 region of humanβ-globin LCRt We also found that the shift band of LPF-βfactor could be competed by humanβ-globin promoter. However, it couldn’t be competed by human E-globin promoter or by human Aβ-globin promoter. Furthermore, our data demonstrated that the binding-sequence of LPF-d factor is 5’CACACCCTA 3’,which is located at the HS2 region ofβ-LCR (from -10845 to -10853 bp) and humanβ-globin promoter (from -92 to -84 bp). We speculated that these regions containing the CACCC box in both the humallβ-globin promoter and HS2 might function as stage selector elements in the regulation of humanβd-globin switching and the LPF-βfactor might be a stage-specific protein factor involved in the regulation of humanβ-globin gene expression. 展开更多
关键词 β-globin promoter HS2 of β-globin LCR trans-acting factor
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Bioinformatics Analysis of the Human TCF7L2 Gene Promoter Region
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作者 Siyuan BAO 《Agricultural Biotechnology》 CAS 2020年第6期11-16,21,共7页
[Objectives]This study was conducted to investigate characteristics of the human TCF7 L2 gene promoter.[Methods]The 2000 bp sequence of the 5’regulatory region of the human TCF7 L2 gene was obtained from the UCSC gen... [Objectives]This study was conducted to investigate characteristics of the human TCF7 L2 gene promoter.[Methods]The 2000 bp sequence of the 5’regulatory region of the human TCF7 L2 gene was obtained from the UCSC genome database.The promoter,transcription factor binding sites,CpG islands,SNPs and so on were analyzed by a variety of online softwares.[Results]The bioinformatics analysis results showed there were at least 5 potential promoters in the positive-sense strand of the 2000 bp sequence,among which-242--192 bp,-853--803 bp might contain core promoters.A TATA box and a CpG island with a length of 499 bp were found.241,944 and 1035(positive-sense strand)transcription factor binding sites were predicted by the AliBaba2.1,PROMO and JASPAR softwares,respectively.207 common transcription factor binding sites in the conserved region of human and mouse homologous TCF7 L2 gene promoter were identified with CONREAL program,involving 66 kinds of transcription factors.Two SNPs were found in the promoter region.[Conclusions]The promoter of the human TCF7 L2 gene was analyzed by bioinformatics,and the promoter characteristics were obtained. 展开更多
关键词 TCF7L2 promoter Transcription factor Transcription factor binding sites BIOINFORMATICS
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