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Progress in Natural Science:Materials International 2007年第10期17卷 1166-1171页

作者： Xu Yufeng, Zhou Gongke, Li Yiqin and Liu Jinyuan(Laboratory of molecular biology and Protein Science Laboratory of the Ministry of Education, department of biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China) Laboratory of molecular biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+concentrations, expression of most members of OsMT-I family was increased, except the type 4 OsMT-Is (OsMT-I-4a, 4b and 4c). In roots, Zn2+significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3a. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance to Zn2+, and zinc accumulation in these yeast cells also increased. These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance of cells by direct binding Zn2+.

关键词： rice metallothionein induced expression Zn2+ tolerance.

EFFECT OF ACTIVE COMPOUNDS ISOLATED FROM PTERIS SEMIPINNATA L ON DNA TOPOISOMERASES AND TYROSINE PROTEIN KINASE AND EXPRESSION OF C-MYC IN LUNG ADENOCARCINOMA CELLS

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Chinese Journal of Cancer Research 2001年第2期13卷 105-109页

作者：李金华梁念慈莫丽儿张晓何承伟 Institute of Biochemistry and molecular biology department of chemistry Guangdong Medical College

Objective: To study the effect of active compound 6F and A from Pteris semipinnata L.(PsL) on the activities of DNA topoisomerase (TOPO) I and II, activities of cytosolic and membrane TPK, and expression of oncogene c-myc in lung adenocarcinoma cells. Methods: The effect of compound 6F and A on activities of cytosolic and membrane TPK was measured by scintillation counting; the effect of compound A on expression of oncogene c-myc was determined by flow cytometry indirect fluorimetry. Results: compound 6F and A could inhibit the activities of TOPO I, and they strongly inhibited the TOPO II in 0.01 mg/L and 10.0 mg/L respectively. Compound A slightly inhibited the activities of membrane TPK, but not the cytosolic one. Compound A could inhibit the expression of oncogene c-myc. Conclusion: Topoisomerases are target of compound 6F and A. Compound A could slightly inhibit the activities of TPK, and showed an inhibitory effect on the expression of oncogene c-myc.

关键词： Pteris semipinnata L. DNA topoisomerase Tyrosine protein kinase c-myc

Crystal Structure of the Coordination Polymer of Sodium with Hydrazone Derivant of Acetoacetanilide

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Chinese Journal of Structural chemistry 2016年第4期35卷 521-528页

作者：董金龙苏峰宋珍李好样任跃红任建国 department of chemistry Taiyuan Normal University School of chemistry and Chemical Engineering Shanxi University Institute of molecular Science Key Laboratory of Chemical Biology and Molecular Engineering of the Education MinistryShanxi University

One new polymer, [Na（NPHSNPAB）（CH3OH）]n, where NPHSNPAB stands for Nphenyl-2-[2-hydroxy-3-sulfo-5-nitrophenylhydrazone]butadione-1,3, has been synthesized and characterized by ^1H NMR and FTIR spectroscopy and single-crystal X-ray diffraction. For this complex： C（17）H（17）N4NaO9S, Mr = 476.39, triclinic system, space group P1, a = 8.8741（18）, b = 10.942（2）, c = 12.039（2） A, α = 65.74（3）, β = 77.49（3）, γ = 84.30（3）o, V = 1040.3（4） A3, Z = 2, Dc = 1.521 g/cm^3, λ = 0.71073 A, F（000） = 492, S = 1.106, R = 0.0614 and w R = 0.1423 for 2945 observed reflections with I 〉 2（I）. X-ray structural analysis revealed that the structure of NPHSNPAB framework was almost planar by C–H···O, N–H···O, O–H···O, and O–H···S hydrogen bonds. Moreover, sodium（I） center was bound by six O and one N atoms, forming the coordination polymer. The molecular packing diagram showed complicated hydrogen bonds and π···π stacking interaction in the polymer. The average bond distance of the two dicyclic units（3.768 A） indicated strong π···π stacking interaction. The complex displays greenyellow emission at room temperature.

关键词： sodium(Ⅰ) complex polymer hydrazone derivant crystal structure hydrogen bonds π···π stacking interaction

molecular cloning and characterization of a cotton phosphoenolpyruvate carboxylase gene

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Progress in Natural Science:Materials International 2008年第5期18卷 539-545页

作者： Zhixin Qiao, Jin-Yuan Liu Laboratory of molecular biology and Protein Science Laboratory of the Ministry of Education, department of biological Sciences and Biotechnology, Tsinghua University, Beijing 100084, China Laboratory of molecular biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Phosphoenolpyruvate carboxylase (PEPC) plays diverse physiological functions during plant development. In this study, a new phos- phoenolpyruvate carboxylase gene GhPEPC2 is isolated from cotton (Gossypium hirsutum cv. zhongmian 35) by RACE-PCR. The cloned cDNA of GhPEPC2 is 3364 bp in length, and has an open reading frame of 2913 bp, encoding for 971 putative amino acids with a calculated molecular mass of 110.6 kD and pI of 5.56. The deduced amino acid sequence of GhPEPC2 shares high similarity with other reported plant PEPCs. Southern blot analysis indicates that the cotton PEPC exists as a small gene family and the GhPEPC2 might have two copies in the cotton genome. The semi-quantitative RT-PCR reveals that GhPEPC2 constitutively expresses in all the tissues of cot- ton and accumulated highly in roots, owers and embryos but relatively low in stems and bers. In addition, the recombinant GhPEPC2 has been puri ed by expressing it in Escherichia coli and the catalytic properties of it were also investigated. The results showed that GhPEPC2 is a typical C3 PEPC with a higher Km (83.6 lM) and lower Vmax (8.0 lmol min 1 mg 1) compared with the C3 PEPCs pre- viously reported.

关键词： Phosphoenolpyruvate carboxylase Recombinant protein Southern blot Cotton

Interactions Between Metal Ions and Carbohydrates: Coordination Behavior of D Ribose to Lanthanide Ions

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Journal of Rare Earths 2002年第5期20卷 339-342页

作者：苏允兰杨丽敏翁诗甫吴瑾光 The State Key Laboratory of Rare Earth Materials chemistry and Applications Department of Chemical Biology College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Lanthanum chloride α D ribopyranose pentahydrate complex was prepared and speculated its structure from the similar IR spectra of corresponding praseodymium and neodymium D ribose complexes, which reveal the coordination behavior of D ribose to lanthanide ions and give us a model of the interactions between metal ions and carbohydrates.

关键词： rare earths lanthanide complexation α D ribopyranose FT IR

A Stable Upstream Stem-loop Structure Enhances Selection of the First 5'-ORF-AUG as a Main Start Codon for Translation Initiation of Human ACAT1 mRNA

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 259-268页

作者： Li YANG, Jiang CHEN, Catherine C. Y. CHANG1, Xin-Ying YANG, Zhen-Zhen WANG,Ta-Yuan CHANG1, and Bo-Liang LI* State Key Laboratory of molecular biology, Institute of Biochemistry and Cell biology, Shanghai Institutes for biological Sciences, the Chinese Academy of Sciences, Shanghai 200031, China department of Biochemistry, Dartmouth Medical School, Hanover, NH 03756, USA 1 State Key Laboratory of molecular biology Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciencesthe Chinese Academy of Sciences Shanghai 200031 China department of Biochemistry Dartmouth Medical School Hanover

Human ACAT1 cDNA K1 was first cloned and functionally expressed in 1993. There are two adjacent in-frame AUG codons, AUG1397–1399 and AUG1415–1417, at 5'-terminus of the open reading frame (ORF, nt 1397–3049) of human ACAT1 mRNA corresponding to cDNA K1. In current work, these two adjacent in- frame AUGs at 5'-terminus of the predicted ORF (5'-ORF-AUGs) as start codons for translation initiation of human ACAT1 mRNA were characterized in detail. Codon mutations indicated that both of these two adja- cent 5'-ORF-AUGs can be selected as start codons but the first 5'-ORF-AUG1397–1399 is a main start codon consistent with that of the predicted ORF of human ACAT1 mRNA. Further deletion and mutation analyses demonstrated that a stable upstream stem-loop structure enhanced the selection of the first 5'-ORF-AUG1397– as a main start codon, in addition to upstream nucleotide A in the –3 position, which is a key site of Kozak 1399 sequence. In addition, result of ACAT1 enzymatic activity assay showed no obvious difference between these two ACAT1 proteins respectively initiated from the two adjacent 5'-ORF-AUGs. This work showed that a stable upstream stem-loop structure could modulate the start codon selection during translation initiation of mRNAs that contain adjacent multi-5'-ORF-AUGs.

关键词： ACAT1 start codon Kozak sequence stem-loop structure

Isolation of the promoter of a cotton β-galactosidase gene (GhGal1) and its expression in transgenic tobacco plants

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Science China(Life Sciences) 2006年第2期49卷 105-114页

作者： WU Aimin LIU Jinyuan Laboratory of molecular biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China Laboratory of Molecular Biology and Protein Science Laboratory of the Ministry of Education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

β-galactosidases (EC 3.***.1.23) constitute a widespread family of glycosyl hydrolases in plants and are thought to be involved in metabolism of cell wall polysaccharides. A cDNA of the cotton (Gossypium hirsutum) β-galactosidase gene, designated GhGal1, has previously been identified and its transcripts are highly abundant at the elongation stage of the cotton fiber. To examine the temporal and spatial control of GhGal1 expression, a transcriptional fusion of the GhGal1 promoter region (1770 bp) with the β-glucuronidase (GUS) reporter gene was introduced into tobacco plants by the Agrobacterium infection method. The resulting transgenic plants showed higher GUS activity of fruit in the transgenic plants than that in the negative and positive controls. Histochemical localization of GUS activity demonstrated that the expression of the GUS gene could be found in the meristem zones of roots, cotyledons, vascular tissues, fruit and trichomes in transgenic tobacco plants. Additionally, se-quence analysis of the regulatory region also revealed several conserved motifs among which some were shared with previously reported fruit/seed-specific elements and the others were related with trichome expression. These results indicated the temporal and spatial expression characterization of the GhGal1 promoter in transgenic tobacco plants and provided an important insight into the roles of GhGal1 in cotton fiber development.

关键词： cotton, β-galactosidase, transgenic tobacco, promoter activity, fruit and trichome expression.

Composite magnetic nanoparticles:Synthesis and cancer-related applications

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Chinese Physics B 2014年第11期23卷 27-32页

作者：蔡苹陈洪敏谢晋 department of chemistry University of Georgia College of chemistry and molecular Sciences Wuhan University

Recent advances in the preparation and applications of composite magnetic nanoparticles are reviewed and summa- rized, with a focus on cancer-related applications.

关键词： magnetic nanoparticles composite nanoparticles bio-applications surface modification

Tetrandrine inhibits Ca2+-activated chloride channel in cultured human umbilical vein endothelial cells

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Acta Pharmacologica Sinica 2004年第3期25卷 73-79页

作者： Qi-zhi FANG1,2,Ning ZHONG1,3,Yi ZHANG1,Zhao-nian ZHOU1,4 1Physiological Lab of Hypoxia,Shanghai Institute of biologicalSciences,Chinese Academy ofSciences,Shanghai200031,China 3department of molecular and Cell biology,University of California at Berkeley,Berkeley,CA 94720,USA 2 Now in CardiovascularResearch Institute,University of Cali- fornia at San Francisco,San Francisco,CA 94143,USA Physiological Lab of Hypoxia Shanghai Institute of Biological Sciences Chinese Academy of Sciences Shanghai 200031 China department of molecular and Cell biology University of California at Berkeley

AIM: To characterize the electrophysiological and kinetic properties of Ca2+-activated chloride channel (CaCC) in cultured human umbilical vein endothelial cell line (HUVEC), and test the inhibitory effects of tetrandrine (Tet) on CaCC. METHODS: Ca2+-activated Cl- currents (ICl,Ca) were recorded by patch-clamp whole cell configurations. [Ca2+]i was measured via intracellular Fura-2 fluorescence intensities. RESULTS: ICl,Ca was activated by increasing [Ca2+]i via direct elevation of intracellular calcium. ICl,Ca showed an apparent outward rectification properties, and it was activated in a voltage- and calcium-dependent mode. Tet dose-dependently inhibited ICl,Ca, the IC50 was (5.2±0.4) μmol/L (n=8 cells). Tet suppressed both voltage-dependent and calcium-dependent activation of ICl,Ca. The activa- tion time constant was (326±12) ms [in the presence of 10 μmol/L Tet, compared to control (175±17) ms, at +100 mV], and Ca2+ concentration for half maximal activation was (387±61) nmol/L for Tet (compared to control (287±36) nmol/L. CONCLUSIONS: Tet effectively blocked ICl,Ca, and such effects might be due to its inhibitory effects on the activation process of Ca2+-activated chloride channel.

关键词： chloride channels endothelium tetrandrine patch-clamp techniques calcium

Synthesis and antitumor activity of α-aminophosphonate derivatives containing thieno[2,3-d]pyrimidines

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Chinese Chemical Letters 2015年第6期26卷 755-758页

作者： Yan-Chun Guo Jing Li Jiao-Li Ma Zhi-Ran Yu Hai-Wei Wang Wen-Juan Zhu Xin-Cheng Liao Yu-Fen Zhao The College of chemistry and molecular Engineering The Key Laboratory of Chemical Biology and Organic Chemistry of Henan ProvinceZhengzhou University department of chemistry College of Chemistry and Chemical EngineeringThe Key Laboratory for Chemical Biology of Fujian ProvinceXiamen University

Two series of thieno[2,3-d]pyrimidine derivatives were designed and synthesized, in which bioactive α-aminophosphonate subunits were introduced at the N3 position through an N-N bond connection. The in vitro cytotoxic activity of the novel compounds was tested against human esophageal carcinoma cells （EC109）, human hepatocarcinoma cells （HepG2）, human gastric carcinoma cells （MGC-803）, respectively, by the MTT method. The evaluation results revealed that compounds fimb, 6mf, 6mg, 6rid and 6nh exerted the most potent inhibition against HepG2, MGC-803 and EC109 cells, respectively. In particular, compound 6rag presented excellent inhibitory effect against HepG2 （91.2%） and MGC-803 （94.4%） cells.

关键词： α-Aminophosphonate derivatives Thieno[2 3-d]pyrimidine Synthesis Antitumor