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Computational Identification of Novel Family Members of MicroRNA Genes in Arabidopsis thaliana and Oryza sativa

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Acta Biochimica et Biophysica Sinica 2005年第2期37卷 7+76-87页

作者： Yang LI Wei LI You-Xin JIN State key laboratory of molecular biology,Institute of Biochemistry and Cell biology.Shanghai Institutes for Biological Sciences,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 Shanghai 200031 China

MicroRNAs(miRNAs)are a class of endogenous small RNAs that play important regulatoryroles in both animals and plants,miRNA genes have been intensively studied in animals,but not in *** study,we adopted a homology search approach to identify homologs of previously validated plantmiRNAs in Arabidopsis thaliana and Oryza *** identified 20 potential miRNA genes in Arabidopsisand 40 in ***,providing a relatively complete enumeration of family members for these miRNAs *** addition,a greater number of Arabidopsis miRNAs(MIR168,MIR159 and MIR172)were found tobe conserved in *** the novel homologs,most of the miRNAs have closely related fellow miRNAs andthe number of paralogs varies in the different miRNA ***,a probable functional segmenthighly conserved on the elongated stem of pre-miRNA fold-backs of MIR319 and MIR159 family *** results support a model of variegated miRNA regulation in plants,in which miRNAs withdifferent functional elements on their pre-miRNA fold-backs can differ in their function or regulation,andclosely related miRNAs can be diverse in their specificity or competence to downregulate target *** that the sophisticated regulation of miRNAs can achieve complex biological effects through qualita-tive and quantitative modulation of gene expression profiles in plants.

关键词： microRNA post-transcriptional gene silencing rice Arabidopsis

POLYMERIZATION OF ETHYLENE WITH UNSYMMETRIC 2,6-BIS(IMINO)PYRIDINE IRON(Ⅱ)COMPLEX

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Chinese Journal of Polymer Science 2002年第3期20卷 205-211页

作者： Zhi Ma Wen-hua Sun Zi-long Li Chang-xing Shao You-liang Hu State key laboratory of Engineering Plastics and the Center for molecular Sciences Institute of Chemistry Chinese Academy of Sciences, Beijing 100080 China State key Lab. of Engineering Plast. Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China

An unsymmetric 2,6-bis(imino)pyridine iron(II) complex 1' was synthesized. The relationship between catalyststructure and its activity in ethylene polymerization is discussed. The kinetic behavior of ethylene polymerization and theeffects of polymerization conditions such as temperature, aluminum/iron molar ratio on the activity of catalyst and thecharacteristics of polyethylene were reported. The unsymmetric catalyst 1' has a good catalytic performance of 3.47×10~6 gPE·mol^(-1)·Fe·h^(-1) at 40℃ with aluminum/iron molar ratio = 2500. A dependence of catalyst activity on themethylaluminoxane (MAO) concentration and reaction temperature was found. The molecular weight (MW) of polyethylenewith broad dispersity is about 10~4-10~5 g/mol. The melting temperature and branching of polyethylenes vary with changingreaction temperature and aluminum/iron molar ratio.

关键词： Unsymmetric 2,6-bis(imino)pyridine iron(Ⅱ) complex Ethylene polymerization Catalyst structure Catalytic activity

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Electron structure and substituent effects in o-,m-,p-IC_6H_4OCH_3 iodoanisoles

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Science China Chemistry 2009年第11期52卷 1932-1937页

作者： TONG ShengRui,WANG WeiGang,MA ChunPing,GE MaoFa & WANG DianXun Beijing National laboratory for molecular Sciences(BNLMS),State key laboratory for Structural Chemistry of Unstable and Stable Species,Institute of Chemistry,Chinese Academy of Sciences,Beijing 100190,China 1. Beijing National laboratory for molecular Sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China

The electronic structures and substituent effects in o-,m-,and p-iodoanisoles have been investigated by ultraviolet photoelectron spectroscopy(UPS).The observed UPS bands were analyzed by combining empirical arguments and theoretical *** to the electron-donating nature of both iodoand methoxy substituents,the first ionization potentials of the three iodoanisoles are lower than those of iodobenzene and *** presence of the two substituents in iodoanisoles leads to an electronrich structure,which might contribute to the observed high reactivity of iodoanisoles in a number of organic reactions.

关键词： electronic structures substituent effects ultraviolet photoelectron spectroscopy reactivity

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molecular mapping of QTLs for root response to phosphorus deficiency at seedling stage in wheat (Triticum aestivum L.)

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Progress in Natural Science:Materials International 2007年第10期17卷 1177-1184页

作者： Li Zhenxing, Ni Zhongfu, Peng Huiru, Liu Zhiyong, Nie Xiuling, Xu Shengbao, Liu Gang and Sun Qixin(key laboratory of Crop Heterosis and Utilization and State key laboratory for Agrobiotechnology, key laboratory of Crop Genomics and Genetic Improvement, Beijing key laboratory of Crop Genetic Improvement, Department of Plant Genetics & Breeding, China Agricultural University, Beijing 100094, China) key laboratory of Crop Heterosis and Utilization and State key laboratory for Agrobiotechnology Key Laboratory of Crop Genomics and Genetic Improvement Beijing Key Laboratory of Crop Genetic Improvement Department of Plant Genetics & Breeding China Agricultural University Beijing 100094 China

Phosphorus (P) deficiency in the soil is one of the major abiotic stresses that limit plant growth and crop productivity throughout the world. Development of cultivars with improved P-deficiency tolerance is an efficient strategy for sustainable agriculture. Plant roots play an important role in crop growth and development, especially in nutrient uptake and improvement of P-efficiency. Mapping quantitative trait loci (QTLs) for root traits and their response to low P stress at seedling stage will facilitate the development of P-efficient wheat cultivars. In this study, 30 QTLs (LOD>2.0) were mapped for the three root traits, such as root length, root number and root dry matter under different P supply conditions and their response to P-stress. These QTLs were distributed on 14 chromosomes, with each of the 5 QTLs explaining more than 10% phenotype variance. Analyses showed that root traits and their response to P-deficiency were controlled by different QTLs. In addition, alleles with positive effects were separated on both parents, and wheat cultivars with improved P-efficiency could be developed by accumulating these positive effect alleles together.

关键词： QTLs roots wheat seedling RIL P-deficiency.

Analysis of the Interaction between hPFTAIRE1 and PLZF in a Yeast Two-hybrid System

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Acta Biochimica et Biophysica Sinica 2006年第3期38卷 164-170页

作者： Yan-Kun GAO~# Mei JIANG~# Tao YANG Jiang-Ye CHEN~* State key laboratory of molecular biology,Institute of Biochemistry,and Cell biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Statekeylaboratoryofmolecularbiology InstituteofBiochemistryandCellBiologyShanghaiInstitutesforBiologicalSciencesChineseAcademyofSciencesShanghai200031China

hPFTAIRE1 is a Cdc2-related kinase family *** search its substrates and regulatoryproteins,hPFTAIRE1 was fused to LexA and used as a bait to screen a human brain LexA two-hybrid *** this screening,seven hPFTAIRE1 interacting proteins,including promyelocytic leukemia zinc finger (PLZF),were *** interaction between PLZF and hPFTAIRE1 was confirmed by β-galactosidase assay andLeu growth *** encodes a transcription factor belonging to the POZ/BTB domain and Krüppelzinc finger (POK) *** highly conserved POZ/BTB domain plays a critical role in *** deleted the POZ/BTB and Krüppel zinc finger domains,respectively,and observed the inter-action between hPFTAIRE1 and truncated PLZFs by liquid β-galactosidase activity assay.A weak interactionwas detected between hPFTAIRE1 and *** also observed the interaction between PLZF and anotherCdc2-related kinase,PCTAIRE1.A similar result was *** interaction between PLZF and hPFTAIRE1or PCTAIRE1 was confirmed by co-immunoprecipitation assay in a yeast *** is a phosphoproteinand plays multiple roles during cell *** results suggest that hPFTAIRE1 and PCTAIRE1 may playimportant roles in the functional regulation of PLZF.

关键词： hPFTAIRE1 PLZF PCTIARE1 yeast two-hybrid interaction

Characterization of ATPase Activity of Recombinant Human Pif1

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Acta Biochimica et Biophysica Sinica 2006年第5期38卷 335-341页

作者： Yu HUANG Deng-Hong ZHANG Jin-Qiu ZHOU Max-Planck Junior Research Group at the State key laboratory of molecular biology,Institute of Biochemistry and Cell biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China Max-Planck Junior Research Group at the State key laboratory of molecular biology Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesShanghai 200031China

Saccharomyces cerevisiae Piflp helicase is the founding member of the Pifl subfamily that isconserved from yeast to *** potential human homolog of the yeast PIFI gene has been cloned fromthe cDNA library of the Hek293 cell ***,we described a purification procedure of glutathione S-transferase（GST）-fused N terminal truncated human Pifl protein（hPif1ΔN）from yeast and characterizedthe enzymatic kinetics of its ATP hydrolysis *** ATPase activity of human Pif1 is dependent ondivalent cation,such as Mg2+,Ca2+and single-stranded *** for ATP for the ATPase activity isapproximately 200 μ*** the ATPase activity is essential for hPifl’s helicase activity,these results willfacilitate the further investigation on hPif1.

关键词： Pifl helicase telomere telomerase ATPase

Dynamics of RNA with A6 bulge loop

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Chinese Science Bulletin 2002年第12期47卷 1003-1006页

作者： LIANG Chongrong & LIU Ciquankey laboratory of Cellular & molecular Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming 650223, China biology Department, Jinan University, Guangzhou 510630, China key laboratory of Cellular & molecular Evolution Kunming Institute of Zoology Chinese Academy of Sciences Kunming China biology Department Jinan University Guangzhou China

In order to understand the behavior of RNAs with large bulges in solution, molecular dynamics was performed on the RNA molecule in water with A6 bulge. The result of simulation showed that nonstacked conformation is the main conformation in large bulges, and the backbone of large bulge is of great conformational flexibility, but bulges-induced bends are relatively rigid. The fluctuation in bulge has little influence on the bend angle of RNAs.

关键词： RNA large bulge conformation bend angle.

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TGF-β1-promoted epithelial-to-mesenchymal transformation and cell adhesion contribute to TGF-β1-enhanced cell migration in SMMC-7721 cells

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Cell Research 2003年第5期13卷 343-350页

作者： ZHEN XU, MIN XIONG SHEN, DONG ZHU MA, LI YING WANG, XI LIANG ZHA key laboratory of Glycoconjugate Research, Ministry of Public Health, Department of Biochemistry and molecular biology, Shanghai Medical College, Fudan University, Shanghai 200032, China 2 Medical School, Huzhou Teacher’s College, Huzhou Zhejiang 313000, China 1key laboratory of Glycoconjugate Research Ministry of Public Health Department of Biochemistry and Molecular Biology Shanghai Medical College Fudan University Shanghai 200032 China. Email: xlzha@*** 2Medical School Huzhou Teacher s College Huzhou Zhejiang 313000 China 1key laboratory of Glycoconjugate Research Ministry of Public Health Department of Biochemistry and Molecular Biology Shanghai Medical College Fudan University Shanghai 200032 China. Email: xlzha@*** 1key laboratory of Glycoconjugate Research Ministry of Public Health Department of Biochemistry and Molecular Biology Shanghai Medical College Fudan University Shanghai 200032 China. Email: xlzha@*** 1key laboratory of Glycoconjugate Research Ministry of Public Health Department of Biochemistry and Molecular Biology Shanghai Medical College Fudan University Shanghai 200032 China. Email: xlzha@***

Transforming growth factor-b 1 (TGF-β1), a multi-function polypeptide, is a double-edged sword in cancer. For some tumor cells, TGF-β1 is a potent growth inhibitor and apoptosis inducer. More commonly, TGF-β1 loses its growth-inhibitory and apoptosis-inducing effects, but stimulates the metastatic capacity of tumor cells. It is currently little known about TGF-β1-promoted cell migration in hepatocellular carcinoma (HCC) cells, let alone its mechanism. In this study, we found that TGF-β1 lost its tumor-suppressive effects, but significantly stimulated cell migration in SMMC-7721 human HCC cells. By FACS and Western blot analysis, we observed that TGF-β1 enhanced the expression of α5β1 integrin obviously, and subsequently stimulated cell adhesion onto fibronectin (Fn). Furthermore, we observed that TGF-β1 could also promote SMMC-7721 cells adhesion onto laminin (Ln). Our data also provided evidences that TGF-β1 induced epithelial-to-mesenchymal transformation (EMT) in SMMC-7721 cells. First, SMM

关键词： TGF-β1 cell migration epitheIial-to-mesenchymal transformation α5β1 integrin.

Identification and characterization of a new member of serpin family- Hon-grES1 in rat epididymis

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Cell Research 2002年第Z2期 407-410页

作者： ZHI HONG HU, QIANG LIU, QUAN SHANG, MIN ZHENG, JUN YANG, YONG LIAN ZHANGState key laboratory of molecular biology, Institute of Biochemistry and Cell biology, Shanghai Institutes for Biological Sciences, the Chinese Academy of Sciences, Shanghai 200031, China

A full length cDNA named HongrESl was isolated and cloned by screening rat epididymis cDNA library using a mouse EST as a probe and 5’RACE followed. It contained 1590bp nucleotides and its predicted protein had 415 amino acid residues including a serpin (serine protease inhibitor) conserved domain. Tissue distribution pattern showed it was specifically expressed in adult rat epididymis; moreover, in situ hybridyza-tion indicated this gene was expressed in a limited region of the cauda epididymis near vas deference. Such kind of expression pattern sugested that HongrESl had potential function in male reproduction.

关键词： HongrESl serpin epididymis α1-antitrypsin in situ hybridization.