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Complete nucleotide sequence of a novel porcine circovirus-like agent and its infectivity in vitro

Science china(Life Sciences) 2008年第5期51卷 453-458页

作者： WEN LiBin1, HE KongWang1, YANG HanChun2, NI YanXiu1, ZHANG XueHan1, GUO RongLi1 & PAN QunXin1 1 key laboratory of Animal and Poultry Diseases Diagnostic of the ministry of agriculture, Jiangsu Academy of agricultural Sciences, Nanjing 210014, china 2 key laboratory of preventive veterinary medicine of ministry of agriculture, college of veterinary medicine, china agricultural university, beijing 100094, china key laboratory of Animal and Poultry Diseases Diagnostic of the ministry of agriculture Jiangsu Academy of Agricultural Sciences Nanjing China key laboratory of preventive veterinary medicine of ministry of agriculture College of Veterinary Medicine China Agricultural University Beijing China

A novel agent (hence termed as P2) was isolated from pig sera in china, which contained covalently bound circular genomic DNAs of 993 nucleotides. Sequence analyses indicated that the agent was closely related to the porcine circovirus (PCV). The molecular clone of P2 was constructed subsequently and used for the following studies. Intracytoplasmic inclusions and intranuclear inclusions were only found in PK-15 cells transfected with the tandem dimer of P2 molecular DNA clone. Intracytoplasmic inclusions were round or irregular in shape and 0.1-0.4 μm in diameter, and intranuclear inclusions were electronically denser than intracytoplasmic inclusions and had two general shapes: round/small (0.1 μm in diameter) and hexagonal/large (0.5―1.4 μm in diameter). The inclusions were not membranously bound. The cells transfected with the tandem dimer of P2 molecular DNA clone were tested positive for P2 DNA at passages 5. The P2 antigen could be detected in both transfected and passaged PK-15 cells. This is the first report regarding the complete nucleotide sequence of a small DNA genome in a circovirus-like infectious agent in vitro.

关键词： P2 porcine circovirus molecular clone PK-15 cells

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Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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Science china(Life Sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, ZHANG HuaiQiang2, SHEN JianZhong3 & GAO PeiJi2 1 Institute of Animal Science and veterinary medicine, Shandong Academy of agricultural Science, Jinan 250100, china 2 State key laboratory of Microbial Technology, Shandong university, Jinan 250100, china 3 college of veterinary medicine, china agricultural university, beijing 100094, china Institute of Animal Science and veterinary medicine Shandong Academy of Agricultural Science Jinan China college of veterinary medicine China Agricultural University Beijing China State key laboratory of Microbial Technology Shandong University Jinan China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC249 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase and declining phase, in each of which obvious variation in physiological and biochemical properties was detected, including total DNA, total protein, and MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic sus- ceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N0/{1+exp[r?(x-BC50)]}, showing as normal distribution at the indi- vidual cell level for an internal population, in which the median bactericidal concentration BC50 repre- sents the mean level of susceptivity, while the bactericidal span BC1-99=(2lnN0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC249 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase and declining phase all increased com- pared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity and research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

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Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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Science china(Life Sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 college of Animal Science and Technology, china agricultural university, beijing 100094, china 2 Vocational and Technologic college, Inner Mongolia agriculture university, Baotou 014109, china 3 college of veterinary medicine, china agricultural university, beijing 100094, china college of Animal Science and Technology China Agricultural University Beijing China Vocational and Technologic college Inner Mongolia Agriculture University Baotou China college of veterinary medicine China Agricultural University Beijing China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

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Tn5-mutagenesis and identification of atr operon and trpE gene responsible for indole-3-acetic acid synthesis in Azospirillum brasilense Yu62

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Progress in Natural Science:Materials International 2006年第4期16卷 366-372页

作者： XIE Baoen and CHEN Sanfeng State key laboratory for Agrobiotechnology, college of Biological Sciences, china agricultural university, beijing 100094, china State key laboratory for Agrobiotechnology College of Biological Sciences China Agricultural University Beijing 100094 China

To bring more information about synthesis of indole-3-acetic acid (IAA) from Azospirillum brasilense, a Tn5-insertion library of A. brasilense Yu62 was constructed and subjected to screening for IAA producing mutants. Two mutants with decreased IAA levels, named as A3 and A24, were isolated. The sequence analysis of loci tagged showed that the Tn5-1063a was located in the atrA gene encoding GntR family transcriptional regulator and trpE gene encoding component I of anthranilate synthase respectively. At the same time. atrB encoding phosphotransferase and atrC encoding aminotransferase were cloned downstream the atrA gene and atrA, atrB and atrC were clustered in an operon. Mutagenesis and complementation studies showed that atrA and atrC were involved in IAA synthesis. IAA levels of trpE mutant and wild-type strain could be improved by adding anthranilate into the medium.

关键词： indole-3-acetic acid (IAA) IAA mutants Azospirillum brasilense atrABC cluster trpE Tn5 transposon.

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Highly Pathogenic H5N1 Influenza Virus Infection in Migratory Birds

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中国实验动物学报 2005年第S1期13卷 11-12页

作者： Jinhua Liu et al.college of veterinary medicine, china agricultural university, beijing 100094, china.

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Protein phosphorylation is involved in the water stress-induced ABA accumulation in the roots of Malus hupehensis Rehd

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Chinese Science Bulletin 2001年第10期46卷 855-858页

作者： ZHANG Dapeng, YANG Hongqiang, JIA Wensuo & HUANG Conglin1. laboratory of Molecular Developmental Biology of Fruit Trees, china agricultural university, beijing 100094, china 2. The key laboratory of Plant Physiology and Biochemistry of agricultural ministry, china agricultural university, beijing 100094, china laboratory of Molecular Developmental Biology of Fruit Trees China Agricultural University Beijing China The key laboratory of Plant Physiology and Biochemistry of agricultural ministry China Agricultural University Beijing China

Water stress-induced ABA accumulation plays a key role in the root to shoot communication and/or the cell to cell signaling under the soil stresses. The signaling of the water stress itself that leads to the accumulation, however, is less known. In this study, we subjected the roots of Malus hupehensis seedlings to water stress treatment and investigated the ABA accumulation in relation to protein phos-phorylation. Our results showed that ABA accumulation could be substantially triggered in 40 min and reached 4 folds in 100 min after treatment with 30% PEG 6000 (polyethylene glycol). The water stress treatment also led to a substantial enhancement of total kinase activity, assessed with histone-111 as substrate, in 15 min and a maximum enhancement in 30 min before it declined to initial level. The Ca2+-dependent kinase activity showed a similar, if not more sensitive, trend. When the roots were fed with labeled 32P-ATP, water stress enhanced the labeling of proteins, which showed a maximum labeling at

关键词： ABA (abscisic acid) water stress protein kinases Malus hupehensis Rehd.

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疱疹病毒膜融合的分子机制

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生物化学与生物物理进展 2010年第6期37卷 583-588页

作者：王晓佳中国农业大学动物医学院农业部人畜共患病重点开放实验室北京100193

囊膜病毒与宿主细胞的膜融合是病毒入侵宿主细胞的重要过程,这一过程涉及到病毒囊膜表面糖蛋白与宿主细胞表面受体之间的相互作用和构象变化.疱疹病毒有多个糖蛋白及不同类型的细胞作用受体,相应的受体-糖蛋白复合体构成方式也有多种,... 详细信息

囊膜病毒与宿主细胞的膜融合是病毒入侵宿主细胞的重要过程,这一过程涉及到病毒囊膜表面糖蛋白与宿主细胞表面受体之间的相互作用和构象变化.疱疹病毒有多个糖蛋白及不同类型的细胞作用受体,相应的受体-糖蛋白复合体构成方式也有多种,其引致的膜融合机制被认为是目前病毒融合机制研究中最复杂的,近年来被广泛研究并取得突破性进展.从病毒糖蛋白与相应受体的结构与功能、受体-糖蛋白复合体的形成与入侵途径,以及膜融合模式几个方面,全面综述疱疹病毒膜融合的分子机制,并展望了未来研究趋势.

关键词：疱疹病毒受体-糖蛋白复合体结构与功能膜融合

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Genetic polymorphisms of milk epithelial mucin of yaks

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Progress in Natural Science:Materials International 2006年第11期16卷 1222-1226页

作者： ZHENG Yucai~1, ZHAO Xingbo~2**, JIN Suyu~1, PENG Xianwen~1 and BAI Wenlin~1 (1. college of Life Science and Technology, Southwest university for Nationalities, Chengdu 610041, china 2. State key laboratory for Agrobiotechnology and ministry of agriculture key laboratory of Animal Genetics, Breeding and Reproduction, china agricultural university, beijing 100094, china) college of Life Science and Technology Southwest University for Nationalities Chengdu 610041 China State key laboratory for Agrobiotechnology Ministry of Agriculture Key Laboratory of Animal Genetics Breeding and Reproduction China Agricultural University Beijing 100094 China

Milk epithelial mucin (MUC1) of yaks was separated by SDS-polyacrylamide gel electrophoresis. A total of nine types of MUC1 were revealed in 427 yaks from five yak breeds including Maiwa yak, Jiulong yak, Tianzhu white yak, Qinghai yak and Tibetan yak. The molecular weights of MUC1 are from 163 kD to 208 kD, most of which are larger than those of bovine. Population genetic analysis shows that the gene frequency and genotype frequency of yak MUC1 differ among breeds, with relatively high gene heterozygosity. The five yak breeds studied fall into two groups according to their milk MUC1 gene frequency, suggesting that milk MUC1 exhibits specificities for local yak groups.

关键词： yak milk genetic polymorphism MUC1.

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Cloning and sequencing of nifBHDKENX genes of Paenibacillus massiliensis T7 and its nif promoter analysis

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Science china(Life Sciences) 2006年第2期49卷 115-122页

作者： ZHAO Hongxin1,2,3, XIE Baoen2 & CHEN Sanfeng1,2 1. State key laboratory for Agrobiotechnology and Biological School, china agricultural university, beijing 100094, china 2. key laboratory for Agro-Microbial Resource and Application of agriculture ministry, china agricultural university, beijing 100094, china 3. Chemical and Biological School, ShenYang Normal university, Shenyang 110034, china State key laboratory for Agrobiotechnology and Biological School China Agricultural University Beijing China key laboratory for Agro-Microbial Resource and Application of agriculture ministry China Agricultural University Beijing China Chemical and Biological School ShenYang Normal University Shenyang China

A 324 bp of nifH fragment was PCR amplified from Paenibacillus massiliensis T7 using the universal degenerate primers. The PCR-amplified nifH fragment was labeled with DIG and then used as a probe in Southern blot analysis. Southern blot result showed that there were two positive signals, indicating that there might be two copies of nifH in P. massiliensis T7. A total of 10254 bp DNA sequence containing purD and nifBHDKENX was obtained by five rounds of inverse-PCR amplifica-tion. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ54-dependent promoter sequence was detected upstream of the nifB gene and nifBHDKENX were likely to be organized in one operon. Assays of β-galactosidase activity of P. massiliensis T7PB carrying a nifB-lacZ fusion under different concentrations of NH4+ and O2 showed that the expression of nifB-lacZ was strongly inhibited by O2.

关键词： Paenibacillus massiliensis T7, nifBHDKENX, nifB-lacZ, inverse-PCR.

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Cloning and characterization of an up-regulated GA 20-oxidase gene in hybrid maize

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Progress in Natural Science:Materials International 2009年第2期19卷 161-166页

作者： Jinkun Du,Yingyin Yao,Zhongfu Ni,Qixin Sun Department of Plant Genetics & Breeding and State key laboratory for Agrobiotechnology,key laboratory of Crop Genomics and Genetic Improvement,ministry of agriculture/beijing key laboratory of Crop Genetic Improvement,china agricultural university,beijing 100094,china Department of Plant Genetics & Breeding and State key laboratory for Agrobiotechnology Key Laboratory of Crop Genomics and Genetic Improvement Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China

Previous studies revealed that GA content and metabolism are positively correlated with a faster shoot growth rate of hybrid,and recently,genes participating in both GA biosynthesis and GA response pathways were also found to be differentially expressed between wheat hybrid and its parental inbreds. In this study,an up-regulated GA 20-oxidase gene in a maize hybrid,designated ZmGA20,was cloned. ZmGA20 contains an open reading frame (ORF) encoding 391 amino acid residues. BLASTX searches in GenBank revealed that the ZmGA20 is homologous to the sequences of GA20ox proteins from different species,and analysis also indicated that ZmGA20 had typical features of GA 20-oxidase proteins,including a "LPWKET" sequence. Semi-quantitative RT-PCR analysis showed that ZmGA20 was expressed in different tissues and/or organs. The expression level of ZmGA20 in the hybrid was higher than that in two parents (in roots,leaves,stems and embryo,and ears). The abundance of ZmGA20 transcript was equal to that of the highly expressed parents,which provided molecular evidence for the observed GA content heterosis in maize hybrids.

关键词： GA 20-oxidase Gene expression Maize Heterosis

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