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Protein & Cell 2010年第4期1卷 363-370页

作者： Xue Yao Shasha Fang Wentao Qiao yunqi geng Yuequan Shen Tianjin Key Laboratory of Protein Science College of Life SciencesNankai University94 Weijin RoadTianjin 300071China Key Laboratory of Molecular Microbiology and Biotechnology(Ministry of Education) the College of Life ScienceNankai University94 Weijin RoadTianjin 300071China

Integrase plays a critical role in the recombination of viral DNA into the host ***,over the past decade,it has been a hot target of drug design in the fight against type 1 human immunodeficiency virus(HIV-1).Bovine immunodeficiency virus(BIV)integrase has the same function as HIV-1 *** have determined crystal structures of the BIV integrase catalytic core domain(CCD)in two different crystal forms at a resolution of 2.45Åand 2.2Å,*** crystal form I,BIV integrase CCD forms a back-to-back dimer,in which the two active sites are on opposite *** has also been seen in many of the CCD structures of HIV-1 integrase that were determined ***,in crystal form II,BIV integrase CCD forms a novel face-toface dimer in which the two active sites are close to each ***,the distance separating the two active sites is approximately 20Å,a distance that perfectly matches a 5-base pair *** on these data,we propose a model for the interaction of integrase with its target DNA,which is also supported by many published biochemical *** results provide important clues for designing new inhibitors against HIV-1.

关键词： bovine immunodeficiency virus integrase catalytic core domain crystal structure dimerization

Borf-1 protein identified as a transcriptional trans-activator of bovine foamy virus

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Chinese Science Bulletin 1999年第11期44卷 1017-1021页

作者： Jiajian Liu Shuhong Liu Qimin Chen yunqi geng Nankai Univ Coll Life Sci Tianjin 300071 Peoples R China

Bovine foamy virus (BFV), a member of the spumavirus subfamily of retroviruses,contains two open reading frames (ORF-1 and ORF-2) in addition to the genes coding for gag,po/and env. Borf-1 protein, encoded by BFV ORF-1, is identified as a transcriptional transactivator, which augments gene expression directed by the viral long terminal repeat (LTR).Further investigations in transient expression assays reveal that the Borf-1 responsive elements are located in the U3 domain of the LTR, upstream from position -140 ( + 1 represents the transcription initiation site), and the BFV RU5 region has an inhibitory effect in LTR-directed gene expression.

关键词： bovine foamy virus (BFV )3026 China Strain transcriptional trans-activator transient expression assay.

MicroRNAs and their role in viral infection

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Frontiers in Biology 2007年第1期2卷 15-20页

作者： MU Junjie YAO Xue CHEN Qimin geng yunqi QIAO Wentao College of Life Science and Tianjin State Laboratory of Microbial Functional Genomics Nankai UniversityTianjin 300071China

Recently,a class of about 22 nucleotides(nt)small RNA has been discovered in many eukaryotes,termed microRNAs(miRNAs),which have a variety of *** recent findings have demonstrated that viruses can also encode their own ***,other findings reveal a relationship between host miRNA and viral *** findings suggest a tight relationship between host and viral infection via miRNA *** article introduces the miRNAs encoded by viruses and reviews the advances of the interaction of the mammalian host miRNAs and viral infection.

关键词： microRNA(miRNA) viral infection small RNA

cis-acting element located in the bovine foamy virus internal promoter possesses the properties of a transcrip-tional enhancer

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Chinese Science Bulletin 2002年第13期47卷 1108-1112页

作者： Wentao Qiao Chunguang Guo Shuhui Wang Jinzhong Wang Qimin Chen yunqi geng Nankai Univ Coll Life Sci Tianjin 300071 Peoples R China

Bovine foamy virus encodes a transcriptional transactivitor, Tas or Borf-1, which governs the level of viral transcripts initiated by both the promoter in the long terminal repeat (LTR) and the internal promoter (IP) located in the env gene through their cis-acting targets. We have identified and characterized a 72 bp TBS (Borf-1) responsive element located in BFV3026, internal promoter (TREIP) by deletion mutant and transient expression assay. This cis-acting target element in the internal promoter has the properties of a transcriptional enhancer which functions independently of its orientation, position and also in heterologous promoters (BFV LTR and bovine immunodeficiency virus, BIV LTR). Alignments reveal that there are positional similarity and sequence homology among BFV TREIP, SFV-1 TREIP proximal element and SFV-3 TREIPH, which suggests that this kind of cis-acting elements possesses some common functional character.

关键词： bovine foamy virus (BFV) internal promoter (IP) Tas responsive element (TRE) enhancer.

Membrane-spanning domain of bovine foamy virus transmembrane protein having cytotoxicity

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Frontiers in Biology 2006年第4期1卷 353-356页

作者： MA Yonggang YU Hong WANG Jinzhong CHEN Qimin geng yunqi College of Life Sciences Nankai UniversityTianjin 300071China

Foamy viruses(FVs)have broad cellular tropism infecting vertebrates from fish to human being,which indicates that Env protein has a high capability for membrane *** features in all FV transmembrane(TM)proteins include a region of hydrophobic domain called membrane-spanning domain(MSD),which contains several stretches of hydrophobic amino *** investigate whether these features were associated with the cytotoxicity effect of TM on Escherichia coli,a series of mutants were constructed and expressed in the *** BL21(DE3)using pET-32a(+)as expressing *** results showed that only TM3 without MSD was expressed in ***,whereas the other two containing full or part of the MSD(TM1 and TM2)could not be ***,the bacterial amount and living bacteria analysis revealed that the cytotoxicity of TM was dependent on its MSD,especially on the stretches of hydrophobic amino *** blotting analysis showed that TM3 protein was purified with affinity purification.

关键词： bovine foamy virus(BFV) membrane-spanning domain(MSD) cytotoxicity

On the structure of AP-4 responsive element in the LTR of Jembrana disease virus

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Chinese Science Bulletin 2003年第2期48卷 1247-1250页

作者： Zijing Liu Hongyan Yin Gang Deng Yuhua Yuan Jinzhong Wang yunqi geng Qimin Chen Nankai Univ Coll Life Sci Tianjin 300071 Peoples R China

Previous studies with deletion and sequence analysis of JDV LTR showed that there is a putative AP-4 responsive element in LTR. By antisense transient assay and gel shifting assay, we for the first time demonstrated that AP-4 modulated JDV gene expression by binding DNA di-rectly to bovine cells. The results, derived from site-directed mutagenesis experiments, suggest that the six base pairs of AP-4 binding site (CAGCTG) have different effects on JDV gene expression. When the first two base pairs changed to GC, JDV gene expression is severely decreased.

关键词： JDV cellular factor AP-4 trans-activator (Tat) LTR site-directed mutagenesis.

Synthesis of Large-Area, Few-Layer Graphene on Iron Foil by Chemical Vapor Deposition

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Nano Research 2011年第12期4卷 1208-1214页

作者： Yunzhou Xue Bin Wu Yunlong Guo Liping Huang Lang Jiang Jianyi Chen Dechao geng yunqi Liu Wenping Hu Gui Yu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy ofSciences Beijing 100190 China

We demonstrate a simple and controllable way to synthesize large-area, few-layer graphene on iron substrates by an optimized chemical vapor deposition （CVD） method using a mixture of methane and hydrogen. Based on an analysis of the Fe-C phase diagram, a suitable procedure for the successful synthesis of graphene on Fe surfaces was designed. An appropriate temperature and cooling process were found to be very important in the synthesis of highly crystalline few-layer graphene. Graphene-based field-effect transistor （FET） devices were fabricated using the resulting few-layer graphene, and showed good quality with extracted mobilities of 300-1150 cm2/（V.s）.

关键词： Graphene iron foil chemical vapor deposition (CVD) method Raman spectroscopy field-effect transistor (FET)

牛泡沫病毒LTR的反式激活因子靶序列研究(英文)

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南开大学学报（自然科学版） 1999年第2期32卷 87-92页

作者：刘佳建耿运琪南开大学生命科学学院

牛泡沫病毒（ＢＦＶ）是反转录病毒科泡沫病毒属成员之一．其基因组除编码ｇａｇ，ｐｏｌ，ｅｎｖ三个结构基因外，在ｅｎｖ和３＇ＬＴＲ之间有２个ＯＲＦ（ＯＲＦ－１和ＯＲＦ－２），编码自身的反式激活因子Ｔａｓ等调节蛋白．本研究... 详细信息

牛泡沫病毒（ＢＦＶ）是反转录病毒科泡沫病毒属成员之一．其基因组除编码ｇａｇ，ｐｏｌ，ｅｎｖ三个结构基因外，在ｅｎｖ和３＇ＬＴＲ之间有２个ＯＲＦ（ＯＲＦ－１和ＯＲＦ－２），编码自身的反式激活因子Ｔａｓ等调节蛋白．本研究利用我们实验室分离鉴定的ＢＦＶ３０２６中国毒株［１２］为材料，克隆Ｏｒｆ－１基因，构建ｐＢＦＶＯＲＦ－１表达质粒，通过带有ｌｕｃ基因的ＬＴＲ系列缺失质粒与ｐＢＦＶＯＲＦ－１共转染，瞬时表达分析结果将ＢＦＶＬＴＲ上Ｔａｓ应答元件（ＴＲＥ）定位于－９８３／－６６８（ＴＲＥＩ），－４７０／－１４０（ＴＲＥＩ）和ＲＵ５区．其中ＴＲＥＩ、ＴＲＥＩＩ为正调控区域，ＲＵ５为负调控区域，并进一步证明ＲＵ５在异源启动子（ＢＩＶＬＴＲ）上具有抑制其下游基因表达的功能．这些结果表明ＢＦＶＴａｓ作用机理与慢病毒（Ｔａｔ）。

关键词：牛病毒泡沫病毒长末端重复序列反式激活因子

Characterization of a full-length infectious clone of bovine foamy virus 3026

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Virologica Sinica 2014年第2期29卷 94-102页

作者： Tiejun Bing Hong Yu Yue Li Lei Sun Juan Tan yunqi geng Wentao Qiao Key Laboratory of Molecular Microbiology and Biotechnology (Ministry of Education) and Key Laboratory of Microbial Functional Genomics (Tianjin) College of Life Sciences Nankai University Department of Molecular and Cellular Pharmacology the Vascular Biology Institute University of Miami School of Medicine National Laboratory of Biomacromolecules Center for Biological Imaging Institute of Biophysics Chinese Academy of Sciences

The biological features of most foamy viruses(FVs) are poorly understood, including bovine foamy virus(BFV). BFV strain 3026(BFV3026) was isolated from the peripheral blood mononuclear cells of an infected cow in Zhangjiakou, China. A full-length genomic clone of BFV3026 was obtained from BFV3026-infected cells, and it exhibited more than 99% amino acid(AA) homology to another BFV strain isolated in the USA. Upon transfection into fetal canine thymus cells, the full-length BFV3026 clone produced viral structural and auxiliary proteins, typical cytopathic effects, and virus particles. These results demonstrate that the full-length BFV3026 clone is fully infectious and can be used in further BFV3026 research.

关键词： bovine foamy virus infectious clone syncytium electron microscopy

转座子Tn917在短小芽孢杆菌中的转座作用

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微生物学报 1992年第4期32卷 305-307页

作者：耿运琪蒋如璋南开大学生物系生物工程研究室

粪链球菌(Streptococcus faecalis)转座子 Tn917已成为枯草芽孢杆菌(***)遗传操作中的一个很有用的工具。Tn917长度为5.4 kb,携带可诱导的红霉素抗性基因,并具有与革兰氏阴性细菌 Tn3族转座子类似的末端重复序列。质粒 pTV32是 pTV1的... 详细信息

粪链球菌(Streptococcus faecalis)转座子 Tn917已成为枯草芽孢杆菌(***)遗传操作中的一个很有用的工具。Tn917长度为5.4 kb,携带可诱导的红霉素抗性基因,并具有与革兰氏阴性细菌 Tn3族转座子类似的末端重复序列。质粒 pTV32是 pTV1的一个衍生质粒,它保留着质粒 pTV1的复制温度敏感特性,并可形成 lacZ 基因转座融合,因而可用来研究有关基因的表达调控机制。本文报道了载体质粒 pTV32在短小芽孢杆菌(***)中的稳定性和 Tn917的转座及其插入诱变效应。

关键词：转座子短小芽孢杆菌转座作用