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The cDNA and Genomic DNA Organization of a Novel Toxin SHT-I from Spider Ornithoctonus huwena

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 656-660页

作者： Peng QIAO, Xiao-Pan ZUO, Zhi-Fang CHAI, and Yong-Hua JI* Institute of Physiology, shanghai Institutes for Biological sciences, chinese academy of sciences, graduate school of the chinese academy of sciences, shanghai 20003., china Institute of Physiology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences

In present study the full-length cDNA of a novel toxin from the venom gland of spider Ornithoctonus huwena, named as SHT-I, has been cloned using the strategy of rapid amplification of cDNA ends, and then the whole genomic sequence of SHT-I (Selenocosmia huwena toxin-I) was determined using sequence-specific primers synthesized based on the acquired 3’ and 5’ ends of SHT-I cDNA sequence. It is unexpectedly found that intron was lacking in the genomic sequence of SHT-I. The result might evoke an interesting question whether the gene code of inhibitor cystine-knot peptides from spider venom is distinct from that of those known toxic peptides of scorpion and cone snail.

关键词： Ornithoctonus huwena spider cDNA genomic DNA peptide toxin ICK motif

Positive Charges on Lysine Residues of the Extrinsic 18 kDa Protein Are Important to Its Electrostatic Interaction with Spinach Photosystem Ⅱ Membranes

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Acta Biochimica et Biophysica Sinica 2005年第11期37卷 737-742页

作者： Jin-Peng GAO Zhen-Hua YONG Feng ZHANG Kang-Cheng RUAN Chun-He XU Gen-Yun CHEN Institute of Plant Physiology & Ecology.shanghai Institutes for Biological sciences,chinese academy of sciences,shanghai 20003.,china Laboratory of Proteomics,Institute of Biochemistry and Cell Biology,shanghai Institutes for Biological sciences,chinese academy of sciences,shanghai 20003.,china College of sciences,Zhejiang University.Hangzhou 310029,china graduate school of the chinese academy of sciences,shanghai 20003.,china Institute of Plant Physiology & Ecology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200032 China graduate school of the chinese academy of sciencesshanghai 20003. China College of sciences Zhejiang UniversityHangzhou 310029 China Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China

To determine the contribution of charged amino acids to binding with the photosystem Ⅱcomplex(PSⅡ),the amino or carboxyl groups of the extrinsic 18 kDa protein were modified with N-succinimidyl propionate(NSP)or glycine methyl ester(GME)in the presence of a water-soluble carbodiimide,*** on isoelectric point shift,4-10 and 10-14 amino groups were modified in the presence of2 and 4 mM NSP,***,3-4 carboxyl groups were modified by reaction with *** of negatively charged carboxyl groups with GME did not alter the binding activity of theextrinsic 18 kDa ***,the NSP-modified 18 kDa protein,in which the positively charged aminogroups had been modified to uncharged methyl esters,failed to bind with the PSⅡ membrane in the presenceof the extrinsic 23 kDa *** defect can not be attributed to structural or conformational alterationsimposed by chemical modification,as the fluorescence and circular dichroism spectra among native,GME-and NSP-modified extrinsic 18 kDa proteins were ***,we have concluded that the positive chargesof lysyl residues in the extrinsic 18 kDa protein are important for its interaction with PSⅡ membranes in thepresence of the extrinsic 23 kDa ***,it was found that the negative charges of carboxylgroups of this protein did not participate in binding with the extrinsic 23 kDa protein associated with PSⅡmembranes.

关键词： extrinsic 18 kDa protein circular dichroism electrostatic interaction chemical modification

Mass Spectrometric Evidence of Heparin Disaccharides for the Catalytic Characterization of A Novel Endolytic Heparinase

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 840-844页

作者： Yapeng CHAO1,3, Shaoxiang XIONG2, Xiulan CHENG1, and Shijun QIAN1* 1Institute of Microbiology, chinese academy of sciences, Beijing 100080, china 2Center of Mass Spectrometry, Institute of Chemistry, chinese academy of sciences, Beijing 100080, china 3graduate school of the chinese academy of sciences, Beijing 100039, china Institute of Microbiology Chinese Academy of SciencesBeijing 100080 China graduate school of the chinese academy of sciencesBeijing 100039 China Center of Mass Spectrometry Institute of Chemistry Chinese Academy of SciencesBeijing 100080 China

Heparinase from different sources can eliminate heparin or/and heparan sulfate into various low-molecular weight heparins with different characteristics. Porcine intestinal mucosa heparin was de- graded into a series of oligosaccharides by a novel heparinase from the species Sphingobacterium. Disaccha- ride components from the digests were separated and purified by ultrafiltration and HPLC. Five major peaks appeared as three types according to their retention time. The mass spectrometry of peak I mainly gave the non-sulfated disaccharide with the mass of 379 Da. Peak II and III were indicated as two major monosulfated disaccharides with molecular mass of 417 and 459 Da respectively. Moreover, the peak III represented an N- acetyl disaccharide. Both peak IV and V showed the same mass of 496 Da, hinting that they were disulfate- substituted disaccharides. No trisulfate-substituted disaccharides were detected in the mixture of the heparin digest though they were abundant in the heparin structure. The results revealed that the heparinase might specifically cut the sites with low sulfated domain in heparin.

关键词： electrospray ionization-mass spectrometry heparin disaccharides heparinase high perfor- mance liquid chromatography Sphingobacterium sp.

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 20003., 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

An Effective Method for Raising Antisera Against β-defensins: Double-copy Protein Expression of mBin1b in E. coli

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Acta Biochimica et Biophysica Sinica 2004年第8期36卷 571-576页

作者： Li-Qing XIAO, Ai-Hua LIU, and Yong-Lian ZHANG 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 20003., 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

Bin1b is a rat epididymis specific β-defensin which may have fertility related functions in addition to its antimicrobial activity. β-defensins are cysteine-rich cationic antimicrobial peptides that have their important implications in innate and adaptive immunity. Though considerable numbers of new β-defensins have been discovered, few corresponding antibodies have been reported. The small peptide with special structure and antimicrobial nature of β-defensins make them very difficult to express in prokaryotic system. Here we adopted a double-copy protein expression scheme based on which not only the mBin1b protein was successfully expressed but also the immunity of the antigen was enhanced. The validity of the antisera was verified by using Western blotting and immunohistochemical analyses. It will be a useful tool for deeply investigating the roles of Bin1b and also provide a simple but effective method in raising antisera against other members of the β-defensin gene family.

关键词： Bin1b epididymis β-defensin double-copy protein polyclonal antiserum

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2,3 and Xin-Wu Cao1,2 1 shanghai Astronomical Observatory, chinese academy of sciences, shanghai 20003., china 2 Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC, shanghai 20003., china 3 graduate school of the chinese academy of sciences, Beijing 100049, china shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint Institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the chinese academy of sciences Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2 cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 278 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Spectral analysis of quasi-stationary sea surface topography from GRACE mission

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Science china Earth sciences 2005年第11期48卷 2040-2048页

作者： ZHANG Zizhan1,2 & LU Yang1,3 1. Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 3. Unite Center for Astro-geodymics Research, chinese academy of sciences, shanghai 20003., china 1. Institute of Geodesy and Geophysics Chinese Academy of Sciences 430077 Wuhan China 2. graduate school of the chinese academy of sciences 100039 Beijing China 3. Unite Center for Astro-geodymics Research Chinese Academy of Sciences 200030 Shanghai China

During the last two decades satellite altimetry has offered an abundance of meas-urements of the sea surface resulting in the improvement of global mean sea surface height (MSSH) and marine geoid determination. On the other hand, with the launching of new genera-tion gravity satellites, some high accuracy long-wavelength gravity models are available. These breakthroughs give us a great opportunity for new estimation of quasi-stationary sea surface topography (QSST). In this paper, the new gravity model GGM01C derived from GRACE mission is briefly presented, and a new global high precision and high-resolution QSST is determined based on the GGM01C model and the global MSSH. The spectral features of the QSST esti-mated by GGM01C and EGM96 gravity model to degree/order 200 are discussed by spectral analysis. As a result, the QSST is mainly composed of long waves, medium waves partially and short waves scarcely, its power spectral structures are different between the zonal direction and the meridional direction, there are great differences between the two models, which maybe ex-plain why the ocean currents derived from the two gravity models by Tapley show different pat-terns.

关键词： quasi-stationary sea surface topography, mean sea surface height, GGM01, fast Fourier transform, spectral analysis

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Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, china graduate school, chinese academy of sciences, Beijing 100080, china 1. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. graduate school Chinese Academy of Sciences 100080 Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

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Detection of Tumor Marker CA125 in Ovarian Carcinoma Using Quantum Dots

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 681-686页

作者： Hui-Zhi WANG, Hai-Yan WANG, Ru-Qiang LIANG, and Kang-Cheng RUAN* Key Laboratory of Proteomics, Institute of Biochemistry and Cell Biology, shanghai Institutes for Biological sciences,chinese academy of sciences, graduate school of the chinese academy of sciences, shanghai 20003., china Key Laboratory of Proteomics Institute of Biochemistry and Cell BiologyShanghai Institutes for Biological SciencesChinese Academy of SciencesGraduate School of the Chinese Academy of SciencesShanghai 200031China

Semiconductor quantum dots (QDs) offer several advantages over organic dyes in fluores- cence-imaging applications, such as higher quantum yield, exceptional photostability, and a narrow, tunable, and symmetric emission spectrum. To explore whether QDs could specifically and effectively label tumor markers and be used in immunohistochemistry as a novel type of fluorescent probe, we used quantum dots with maximum emission wavelength 605 nm (QD605) to detect the ovarian carcinoma marker CA125 in specimens of different types (fixed cells, tissue sections, and xenograft piece). Additionally, we compared the photostability of QD signals with that of a conventional organic dye, FITC. All labeling signals of QDs were found to be more specific and brighter than those of FITC. Moreover, the QDs exhibited exceptional photostability during continuous illumination for 1 h by a high-intensity laser (Ar laser power 100 mW) at 488 nm, while the FITC signals faded very quickly and became undetectable after 24 min of illumination. These results indicate that QD-based probes can offer substantial advantages over existing fluorophores in many applications, and can be used effectively in immunohistochemistry as a novel class of fluorescent probes.

关键词： quantum dots detection of tumor marker CA125 ovarian carcinoma