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Cell Research 1998年第3期8卷 209-218页

作者： YAN ZHI JIANG ruo lan qian(Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai 200051, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai 200031 China

The nucleax mains attachment regions(MARs) and the binding nuclear matrix proteins in the 5'-flalildng cisacting elements of the humanε-globin gene have been examined. Using in vitro DNA-matrix binding assay,it has been shown that the positive stage-specific regulatory element (ε-PREII, -446bp-419bp) upstream of this gene could specifically associate with the nuclear matrix from K562 cells, indicating thatε-PREII mad be an erythroidspecilic facultstive MAR. In gel mobility shift assay and Southwestern blotting assal an eothroid-specific nuclear matrix protein (ε-NMPk) in K562 cells has been revealed to bind to this positive regulatory element (E-PREII). Furthermore, we demonstrated that the silencer (-392hp -177bp) uP8tream of the humanε-globin gene could associate with the nuclear matrices from K562, HEL and Raji cells. In addition, the nucleax matrix proteins prepared from these three cell lines could also bind to this silencer, suggesting that this silencer element linght be a constitutive nuclear mains attachment region (constitutive MAR). Our results demonstrated that the nucleax madrid and nuclear mains proteins lxilght play an important role in the regulation of the human 5-globin gene expression.

关键词： Human ε-globin gene nuclear matrix attachment regions nuclear matrix proteins K562 cells

Trans-acting factors from the human fetal liver bindingto the human ε-globin gene silencer

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Cell Research 1997年第2期7卷 151-159页

作者： YAN ZHI JIANG CHU JIANG ruo lan qian(Shanghai Institute of Cell Biology, Chinese Academy ofSciences, Shanghai 200031, China) Shanghai Institute of Cell Biology Chinese Academy of Sciences.

The developmental stage-specific silencing of the human ε-globin gene during embryonic life is controlled, inpart, by the silencer (-392bp～-177bp) upstream of thisgene. In order to elucidate its role, the nuclear extractfrom the human fetal liver has been prepared and the interactions between trans-acting factors and this silencerelement have been examined. By using DNasel footprinting assay, a major protected region from -278bp to -235bpwithin this silencer element was identified. Furthermore,we found in gel mobility shift assay and Southwestern blotting assay that there were at least four trans-acting factors (MW ≈ 32, 28, 26 and 22kD) in the nuclear extractisolated from the human fetal liver, which could specifically bind to this region. Our results suggested that thesetrans-acting factors might play an important role in silencing the human embryonic ε-globin gene expression at thefetal stage through the interactions with this silencer.

关键词： Human ε-globin gene silencer transacting factor

The apoptosis of HEL cells induced by hydroxyurea

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Cell Research 1997年第1期7卷 91-97页

作者： GUI CHANG YUN CHU JIANG HENG YUE XIE ruo lan qian(Shanghai Institute of Cell Biology, Chinese Academy of Sciences, Shanghai 200031) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai 200031&#x0002A Dedicated to Professor Lu Ji SHI's 80th birthday† The project was supported by National Natural Science Foundation of ChinaReceived 19March1997 Revised 9April1997 Accepted 5June1997

Hydroxyurea has been used to synchronize cultured cells to S-phase and used to treat patients with sicklecell anemia. Recently, we found that hydroxyurea can induce the apoptosis of HEL (human erythroleukemia) *** induced HEL cells showed ultrastructurally chromatin condensation with regular crescents at the nuclear edges and apoptotic bodies. However, the cells of K562, another human erythroleukemia cell line, did not show such morphological changes. Under fluoroscope, the HEL cells after induction often displayed a clear reduction in nuclear diameter and nuclear chromatin cleavage and condensation and the presence of nuclear ring and apoptotic bodies. Analysis with flow cytometry showed that the percentage of apoptotic cells is about 30-40% after HEL cells were induced by hydroxyurea for 3 days. DNA ladder can be observed by electrophoretic analysis.

关键词： HEL cells hydroxyurea apoptosis

Functional Analysis of Multiple Transcription Factor Sites in a Regulatory Element of Human ε-Globin Gene

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 673-680页

作者： Chun-Hui HOU, Jian HUANG, and ruo-lan qian* State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai 200031, China State Key Laboratory of Molecular Biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

The developmental control of the human ε-globin gene expression is mediated by transcrip- tional regulatory elements in the 5’ flanking DNA of this gene. A previously identified negative regulatory element (–3028 to –2902 bp, termed ε-NRAII) was analyzed and one putative NF-κB site and two GATA sites locate at –3004 bp, –2975 bp and –2948 bp were characterized. Electrophoresis mobility shift assay (EMSA) showed that the putative NF-κB site was specifically bound by nuclear proteins of K562 cells. Data obtained from transient transfection showed that the expression of reporter gene could be upregulated about 50% or 100% respectively when ε-NRAII was inserted upstream of the SV40 promoter or ε-globin gene proximal promoter (–177 bp to +1 bp), suggesting that ε-NRAII might not be a classic silencer. Mutation in the putative NF-κB site or in the GATA site (at –2975 bp) slightly reduced the expression of reporter gene driven by SV40 promoter or ε-globin gene proximal promoter. However, the mutation of GATA site at –2948 bp remarkably reduced the reporter gene activity driven by SV40 promoter, but not by ε-globin gene proximal promoter. Further mutation analysis showed that the negative effect of mutation in GATA site at –2948 bp on SV40 promoter was not affected by the mutation of the putative NF-κB site, whereas it could be abolished by the mutation of GATA site at –2975 bp. Furthermore, the mutation of both GATA sites could synergistically reduce the reporter gene activity driven by ε-globin gene proximal promoter. Those results suggested that ε- NRAII might function differently on the SV40 promoter and ε-globin gene proximal promoter.

关键词： ε-globin gene regulatory element NF-κB GATA

Tunable Phase Structure of Side-chain Liquid Crystalline Polymers Enabled by Molecular Engineering of Dual Mesogenic Cores

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Chinese Journal of Polymer Science 2024年第10期42卷 1459-1469,I0009页

作者： Wen-Huan Yao lan-Sheng Liu Jie Zhao Yan-Xia Wang An-Zhi Ma Zheng-Rui Ma lan-Ying Zhang ruo-Chen lan College of Chemistry and Chemical Engineering Hunan UniversityChangsha410082China Key Laboratory of Eco-Functional Polymer Materials of the Ministry of Education Key Laboratory of Eco-Environmental Polymer Materials of Gansu ProvinceCollege of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou730070China Department of Materials Science and Engineering College of EngineeringPeking UniversityBeijing100871China Institute of Advanced Materials&Key Lab of Fluorine and Silicon for Energy Materials and Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China

A series of novel side-chain liquid crystalline(SCLC)copolymers were synthesized by attaching two distinct mesogenic units,namely a chiral cholesteryl-based monomer(M1)and an achiral biphenyl-based monomer(M2),to a poly(3-mercaptopropylmethylsiloxane)(PMMS)backbone via thiol-ene click *** influence of side chain composition on the self-assembly behavior and phase structures of these SCLC copolymers was systematically investigated using different *** indicate that three distinct liquid crystalline phases and four unique molecular configurations were identified within the polymer series,with the emergence of the liquid crystalline phase being a synergistic outcome of the two distinct side *** study underscores the critical influence of side chain dimensions,rigidity,and spatial volume on the self-assembly structures and phase characteristics of liquid crystalline polymers,providing valuable insights for the rational design and development of advanced functional materials with tailored properties.

关键词： Liquid crystalline copolymers Self-assembly Phase structure Chiral molar ratio

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Studies on DNA-protein interactions in the upstream regulatory region of the human ε-globin gene promoter

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Cell Research 1996年第2期6卷 101-114页

作者： YAN ZHI JIANG YA DI CHEN ruo lan qian (Shanghai Institute of Cell Biology, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China)( To whom correspondence should be addressed) Shanghai Institute of Cell Biology Chinese Academy of Sciences Shanghai China

The erythroid- and developmental stage-specific expression of the human ε-globin gene is controlled, in part,by the 5'-flanking DNA sequence of this gene. In the present study, we have used DNA-protein binding assays to identify trans-acting factors which regulate the temporal expression of the human ε-globin gene during development. Using gel mobility shift assays and DNasel footprinting assays, a nuclear protein factor (termed ε-SSF1) in the nuclear extracts from mouse haematopoietic tissues at d 11 and d 13 of gestation was identified. It could specifically bind to the positive control region (between -535 and -453bp) of the human ε-globin gene. We speculated that the E-SSF1 might be an erythroid- and developmental stage-specific activator. In addition, we found another nuclear protein factor (termed ε-R1) in the nuclear extract from mouse fetal liver at d 18 of gestation, which could strongly bind to the silencer region (between -392 and -177bp) of this gene. Therefore, we speculated that the ε-R1 might be an erythroid- and developmental stagespecific repressor. Our data suggest that both ε-SSF1 and ε-R1 might play important roles in developmental regulation of the human ε-globin gene expression during the early embryonic life. On the other hand, we observed that the binding patterns of nuclear proteins from three cell lines (K562, HEL and Raji) to these regulatory regions were partially different. These results suggest that different trans-acting factors in K562, HEL and Raji cells might be responsible for activating or silencing the human ε-globin gene in three different cell lines.

关键词： Human ε-globin gene positive control region silencer trans-acting factor

Direct Conversion of Methane to Propylene

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Research 2024年第2期2023卷 463-472页

作者： Yunpeng Hou Yuxiang lan Chao qian Shaodong Zhou College of Chemical and Biological Engineering Zhejiang Provincial Key Laboratory of Advanced Chemical Engineering Manufacture TechnologyZhejiang University310027 HangzhouP.R.China Zhejiang Provincial Innovation Center of Advanced Chemicals Technology Institute of Zhejiang University-Quzhou324000 QuzhouP.R.China

Nonoxidative coupling of methane exhibits promising prospect in that it affords value-added hydrocarbons and hydrogen with high atom ***,challenge remains in direct,selective conversion of methane to more valuable hydrocarbons like *** current work presents a catalyst with well-dispersed Ta atoms anchored by graphitic C_(3)N_(4)-supported *** a catalyst is able to convert methane selectively to ethylene and propylene at a relatively low temperature(350℃).The conception of the active center and construction of the catalyst have been described,and the origins of the catalytic performance are discussed.

关键词： methane catalyst hydrocarbons

Function of GATA transcription factors in hydroxyurea-induced HEL cells

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Cell Research 2001年第4期11卷 301-310页

作者： ZHANG SHU BING, QI YE HE, HUI ZHAO, CHANG YUN GUI, CHU JIANG, ruo lan qian Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yueyang Road, Shanghai 200031, China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China. Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences 320 Yueyang Road Shanghai 200031 China.

HEL cells, a human erythroleukemia cell line, mainly express the fetal (r)globin gene and trace amount of the embryonic (E)globin gene, but not adult (B) globin gene. Here we show that hydroxyurea (HU) can induce HEL cells to express adult (B) globin gene and lead these cells to terminal differentiation. Results showed in Gel mobility shift assays that GATA factors could specifically bind to the regulatory elements of human B- globin gene, including the proximal regulatory element (the B- promoter) and the distal regulatory elements (the DNase I hypersensitive sites in the LCR, HS2-HS4 core sequences). However, the DNA binding patterns of GATA factors were quite different between HU-induced and uninduced HEL cells. Western-blot analysis of nuclear extracts from both the uninduced and HU- induced HEL cells revealed that the level of GATA-2 transcription factor decreased, whereas the level of GATA-1 transcription factor increased following the time of hydroxyurea induction. Furthermore, using RT-PCR analysis the expression of human B-globin gene in HU-induced HEL cells could be blocked again when HEL cells were incubated in the presence of antisense oligonucleotides for hGATA-1, suggesting that the upregulation of hGATA-1 transcription factor might be critical for the expression of human β- globin gene in HU-induced HEL cells.

关键词： GATA transcription factors human β-gobin gene HEL cells hydroxyurea.

Identification of a NF-кB site in the negative regulatory element (ε-NRAII) of human ε-globin gene and its binding protein NF-кB p50 in the nuclei of K562 cells

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Cell Research 2002年第1期12卷 79-82页

作者： CHUN Hui HOU, JIAN HUANG, ruo lan qian Group of Globin Gene Expression and Regulation, State Key Labortory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai Group of Globin Gene Expression and Regulation Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences State Key Labortory of Molecular Biology 上海 200031 Group of Globin Gene Expression and Regulation Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences State Key Labortory of Molecular Biology 上海 200031

The developmental control of the human e-globin gene expression is mediated by transcription regulatory elements in the 5’ flanking DNA of this gene. Sequence analysis has revealed a DNA motif (GGGGAATTTGCT) similar to NF-кB consensus sequence resides in the negative regulatory element (-3028bp～ -2902bp, termed ε-NRAII) 5’ to the cap site of this gene. NRF DNA fragment (-3010bp～ -2986bp) containing the NF-кB motif similar sequence was synthesized and used in electrophoresis mobility shift assay (EMSA) and competitive analysis. Data showed that a protein factor from nuclear extracts of K562 cells specifically interacted with NRF DNA fragment. The synthetic NF DNA fragment (containing NF-кB consensus sequence) could competed for the protein binding, but MNF DNA fragment (mutated NF-кB motif) could not, suggesting that the binding protein is a member of NF-кB/Rel family. Western blot assay demonstrated that the molecular weight of NF-кB protein in the nuclei of K562 cells is 50ku. We suggested that NF-кB p50 may play an important role in the regulation of human c-globin gene expression.

关键词： Human ε-globin gene negative regulatory element NE-кB p50.

Challenges and countermeasures for developing countries in addressing loss and damage caused by climate change

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Advances in Climate Change Research 2024年第2期15卷 353-363页

作者： Shuo LIU Yu-E LI Bin WANG An-Dong CAI Chao FENG Hua lan ruo-Chen ZHAO Institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural SciencesBeijing 100081China Key Laboratory of Agricultural Environment Ministry of Agriculture and Rural AffairsBeijing 100081China China Clean Development Mechanism Fund Management Center Beijing 100045China School of International Law China University of Political Science and LawBeijing 100088China

Loss and damage caused by extreme climate events have attracted increasing *** 28th Conference of the Parties to the United Nations Framework Convention on Climate Change(hereinafter referred to as the Convention)has agreed to adopt Loss and Damage Fund agreement,which identified the source of funding and the funds to be entrusted to the World ***,there is still ambiguous that how to allocate the funds could accelerate the effectiveness of meeting the needs for developing ***-disaster prevention and preparedness is one of the most effective measures to deal with loss and damage,which closely related to *** studies rarely analyzed quantitatively the financial needs of pre-disaster prevention and preparedness relating to adaptation to reduce loss and *** on the official reports submitted by countries under the Convention,this study analyzes the annual change in the total financial support provided by developed countries to developing countries,the proportion of pre-disaster prevention and preparedness in the adaptation needs of developing countries,and the progress in raising the current annual funding target of 100 billion USD for developed countries,to reveal the financial and technical challenges facing by developing countries on addressing loss and *** results show that by 2030,the total adaptation financial needs of developing countries are estimated to be about 3.8 trillion USD,of which pre-disaster prevention matters account for about 9%.Therefore,by 2030,developing countries will need about 342 billion USD in pre-disaster prevention and preparedness finance to withstand loss and *** addition,developing countries face a lack of technical methods to quantify information about their *** on the above analysis,this study puts forward countermeasures and suggestions,including strengthening the allocation amount of loss and damage fund on pre-disaster warning,prevention and control actions,and

关键词： Loss and damage Funding mechanism Pre-disaster warning and preparedness Convention negotiations Countermeasures