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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 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

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 (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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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 1. Institute of Animal Science and veterinary medicine Shandong Academy of Agricultural Science Jinan 250100 China 3. college of veterinary medicine China Agricultural University Beijing 100094 China 2. State Key Laboratory of Microbial Technology Shandong University Jinan 250100 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; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2lnN 0)/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; declining phase all increased compared 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; 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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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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Neuroglobin mutation associated with hypoxia adaptation in Tibet chicken

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Progress in Natural Science:Materials International 2007年第12期17卷 1419-1424页

作者： Zhang Lifan1, Liu Chong2, Lian Linsheng3, Zhao Chunjiang1, Bao Haigang1 and Wu Changxin1(1. college of Animal Science and Technology, china agricultural university, beijing 100094, china 2. college of Biological Science, china agricultural university, beijing 100094, china 3. college of Animal Science and Technology, Yunnan agricultural university, Kunming 650201, china) college of Animal Science and Technology China Agricultural University Beijing 100094 China college of Biological Science China Agricultural University Beijing 100094 China college of Animal Science and Technology Yunnan Agricultural University Kunming 650201 China

Globin protein family plays an important role in storing and transporting oxygen. As a newly reported globin, the revealed function of neuroglobin includes binding and storing oxygen as well as facilitating the utilization of oxygen in neuronal cells. In the present study, mutations in exons of chicken Ngb gene were identified with the method of sequencing and created restriction site PCR in Tibet chicken and other four lowland chicken breeds. The mutations of Lys-2224(E4)-Asn and Ser-2279(E4)-Gly were identified in exon 4 of the gene. The Lys-2224(E4)-Asn mutation existed only in Tibet chicken and the mutation frequencies increased with increasing altitude. Analysis of the haplotype and diplotype of the two mutations in Tibet chicken populations of different altitudes showed that the frequencies of TG haplotype and TTGG diplotype also increased with increasing altitude, while the reverse tendency was found on GGAA diplotype. Under the hypoxic simulation incubation, the main haplotype was TG in living embryos and GA in dead embryos. The results showed that the Lys-2224(E4)-Asn mutation may be a specific mutation associated with hypoxia adaptation in Tibet chicken.

关键词： Tibet chicken neuroglobin hypoxia adaptation Ngb gene mutation.

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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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Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural Science:Materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (college of Agronomy and Biotechnology, china agricultural university, beijing 100094, china) college of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in china have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： Macrosiphum miscanti microsatellite gene flow migration.

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A five-fold pig bacterial artificial chromosome library:a resource for positional cloning and physical mapping

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Progress in Natural Science:Materials International 2006年第08期16卷 889-892页

作者： LIU Wei, ZHANG Ying, LIU Zhaoliang, GUO Li, WANG Xiaobo, FEI Jing, FENG Jidong, ZHAO Rui, HU Xiaoxiang and LI Ning (The State Key Laboratory for Agro-Biotechnology, college of Biology, china agricultural university, beijing 100094, china college of Animal Science and Technology, china agricultural university, beijing 100094, china) [a]The State Key Laboratory for Agno-Biotechnology College of Biology China Agricultural University Beijing China [b]college of Animal Science and Technology China Agricultural University Beijing China

A pig BAC library was constructed with genomic DNA from a male Erhualian pig. After partial digestion with HindⅢor BamHⅠthe fragments obtained were cloned into the pBeloBAC11 vector. The library consists of 184320 clones which stored in 480 pieces 384-well plates (20 plates per superpool). A two-step 4-dimension PCR screening system was established to screen the positive clones. An average insert size of 128 kb was estimated from 105 randomly isolated clones, which indicates that the library is more than five times of genomic coverage. For the demonstration of the probability to pick out any unique genes or DNA markers from the library, 10 single-copy genes were screened out and the positive clones were yielded between 1 and 8 with an average of 3.6. Positive superpools were obtained for 32 microsatellite markers selected from different regions of pig genome. The number of positive superpools for each marker varies from 1 to 9 with an average of 4.78. This BAC library provides an additional resource for pig physical mapping and gene identifica-

关键词： pig BAC library PCR screening system.

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Aberrant histone H4 acetylation in dead somatic cell-cloned calves

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Progress in Natural Science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, beijing 100094, china b beijing Gene & Protein Biotechnology Co. LTD, beijing 100094, china c college of Animal Science and Technology, china agricultural university, beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China college of Animal Science and Technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

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

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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 Poultry Diseases Diagnostic of the Ministry of Agriculture Jiangsu Academy of Agricultural Sciences Nanjing 210014 China Key Laboratory of Preventive veterinary medicine of Ministry of Agriculture College of Veterinary Medicine China Agricultural University Beijing 100094 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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Enhancement of monacolin K production via intergeneric protoplast fusion between Aspergillus terreus and Monascus anka

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Progress in Natural Science:Materials International 2007年第6期17卷 703-707页

作者： Chen Zhi, Lin Wen, Yu Ping and Song Yuan(Department of Microbiology, college of Biological Sciences, china agricultural university, beijing 100094, china) Department of Microbiology College of Biological Sciences China Agricultural University Beijing 100094 China

Intergenric protoplast fusion between Aspergillus terreus CA99 and Monascus anka M-3, the high and low producers of monacolin K respectively,was performed for enhancement of monacolin K production. The 24-hour-old mycelia of A. terreus CA99 and M. anka M-3 were treated with 0.5% lywallzyme, 0.3% snailase and 0.3% cellulase at 34℃ for 5 h and at 30℃ for 3.5 h, and their protoplasts formation reached 1.76×107/mL and 1.68×107/mL respectively. Parental protoplasts were irradiated with a 30 W UV light away from 30 cm for 3 min and then mixed. The mixture was incubated with 30% PEG 6000 for 15 min. The reviving fusants were isolated on the regeneration plates. Of the 363 fusants isolated, over 100 showed enhanced monacolin K production compared with the parental strain M. anka M-3. Ten of them produced monacolin K about 1.6-fold of that *** M-3 does and the monacolin K titer of two fusants (F49 and F104) increased by about 1-fold. The monacolin K yields of F49 and F104 were 460 μg/mL and 457 μg/mL respectively. In optimized fermentation medium, the monacolin K titer of F49 reached 1216 μg/mL.

关键词： monacolin K Monascus anka Aspergillus terreus protoplast fusion fermentation.

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