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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,{2., china 2. Key Laboratory for Agro-Microbial Resource and Application of Agriculture Ministry, china agricultural university,{2., china 3. Chemical and biological School, ShenYang Normal university, Shenyang 110034, china 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

A 32. 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; 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 102.4 bp DNA sequence containing purD; nifBHDKENX was obtained by five rounds of inverse-PCR amplification. The predicted proteins of nifBHDKENX had high homology with those from other nitrogen-fixing bacteria. Only one putative σ[54]-dependent promoter sequence was detected upstream of the nifB gene; 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 [+]; O2.showed that the expression of nifB-lacZ was strongly inhibited by O2.

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

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,{2., beijing 100094, china 2.Vocational and Technologic college, Inner Mongolia Agriculture university, Baotou 014109, china 3 college of Veterinary Medicine,{2., 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 (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

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2. LIU GuoQuan2. LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering college, Shandong agricultural {2., Tai’an 2.1018, china 2.college of Materials science and Engineering, {2. of science and Technology, beijing 100083, china 3 college of Material science and Engineering, beijing {2. of Chemical Technology, beijing 10002., china Mechanical Electronic Engineering college Shandong Agricultural University Tai’an 271018 China college of Materials science Engineering University of Science Technology Beijing 100083 China college of Material science Engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

Genetic analysis on 3'- terminal flanking region of uncoupling protein 3 in different pig breeds

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Chinese science Bulletin 2002年第18期47卷 1541-1543页

作者： FANG Meiying, ZHAO Xingbo, LI Ning & WU Changxincollege of Animal science and Technology,{2., beijing 100094, china State Key Laboratory for Agrobiotechnology,{2., beijing 100094, china college of Animal science and Technology China Agricultural University Beijing China State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China

The 3’-terminal flanking region of porcine uncoupling protein 3 (UCP3) was cloned, the sequence data revealed 15 nucleotide substitutions among Landrace and three Chinese native pig breeds named Neijiang, Minpig and Erhualian. The continuous 9 polymorphic sites were checked by PCR-RFLP, the results indicated that Erhualian had extraordinary gene frequency, presented most significant difference by x2.test compared with Landrace, Largewhite, Neijiang and Minpig respectively, significant level compared with Meishan; and Meishan also had significant difference compared with Landrace and Minpig respectively. These results can be concluded that Taihu pigs have special genetic characteristics among pig breeds.

关键词： pig uncoupling protein gene clone PCR-RFLP.

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,{2., 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.

Research on the method for retrieving soil moisture using thermal inertia model

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science china Earth sciences 2006年第5期49卷 539-545页

作者： LIU Zhenhua1 & ZHAO Yingshi2.1. Information college, South china agricultural university, Guangzhou 510642.{2. 2. Graduate university of Chinese Academy of sciences, beijing 100049,{2. 1. Information college South China Agricultural University Guangzhou 510642 China 2. Graduate university of Chinese Academy of sciences Beijing 100049 China

In order to improve accuracy of soil moisture inversion using remote sensing, a new thermal inertia model is proposed in this paper. The improved model needs only surface maximum temperature as the temperature parameter input instead of input of the surface temperature difference, as well as the surface sensible and latent fluxes are introduced into boundary conditions of thermal conductivity equation. Furthermore, surface soil conductive heat transfer equation of two-layer model is used to solve the soil thermal inertia so that the remote sensing thermal inertia method can be ap- plied to regions with better-covered vegetation, but usually only for the bare areas or worse vegetation covered areas. The model has been tested at several locations in the area of west Inner Mongolia. Comparing the simulation of the new model with the measurements obtained by apparent thermal inertia and by field test, the result shows that the inertia thermal model can be used to estimate soil moisture in more reasonable accuracy.

关键词： thermal model, thermal conductivity equation, soil initial, sensible flux, latent flux, two-layer model.

Simulation study on the efficiencies of MOET nucleus breeding schemes applying marker assisted selection in dairy cattle

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science china(Life sciences) 2009年第3期52卷 296-306页

作者： LUO WeiZhen,WANG YaChun & ZHANG Yuan Department of Animal Genetics & Breeding,college of Animal science and Technology,{2. agricultural university,beijing 100094,{2. 1. Department of Animal Genetics & Breeding College of Animal Science and Technology China Agricultural University Beijing 100094 China

Advantages of breeding schemes using genetic marker information and/or multiple ovulation and embryo transfer(MOET) technology over the traditional approach were extensively evaluated through *** yield was the trait of interest and QTL was the genetic marker *** dairy cattle breeding scenarios were considered,i.e.,traditional progeny testing breeding scheme(denoted as STANPT),GASPT scheme including a pre-selection of young bulls entering progeny testing based on their own QTL information,MOETPT scheme using MOET technology to generate young bulls and a selection of young bulls limited within the full-sib family,GAMOPT scheme adopting both QTL pre-selection and MOET technology,COMBPT scheme using a mixed linear model which considered QTL genotype instead of the BLUP model in GAMOPT,and three non-progeny testing schemes,*** MOET,GAMO and COMB schemes,corresponding to MOETPT,GAMOPT and COMBPT with progeny testing being part of the *** were selected based on their breeding value which was estimated under an animal model *** selection over 17 years was performed in the simulations and 30 replicates were designed for each *** influences of using QTL information and MOET technology on favorable QTL allele frequency,true breeding values,polygenetic breeding values and the accumulated genetic superiority were extensively evaluated,for five different populations including active sires,lactating cows,bull dams,bull sires,and young *** results showed that the combined schemes significantly outperformed other approaches wherein accumulated true breeding value *** difference between schemes exclusively using QTL information or MOET technology was not *** STANPT scheme was the least efficient among the 8 *** schemes using MOET technology had a higher polygenetic response than others in the 17th *** increases of frequency of the favorable QTL allele varied more greatly across t

关键词： dairy cattle marker-assisted selection two-stage selection MOET QTL

Isolation and expression of an aquaporin-like gene VfPIP1 in Vicia faba

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Progress in Natural science:Materials International 2005年第6期15卷 496-501页

作者： CUI Xianghuan, HAO Fushun, CHEN Hui, CAI Jinghui, CHEN Jia and WANG Xuechen*(State Key Laboratory for Plant Physiology and Biochemistry, college of biological {2., china agricultural university, beijing 100094, china) State Key Laboratory for Plant Physiology and Biochemistry College of Biological Science China Agricultural University Beijing 100094 China

To explore the effects of aquaporins on stomatal movement, we isolated a full length cDNA of aquaporin-like gene VfPIP1 (Vicia faba plasma membrane intrinsic protein gene, GenBank accession number: AY667436), which encodes for a 2.0-amino-acid polypeptide, from Vicia faba leaf epidermis by 5′/3′ RACE (Rapid Amplification of cDNA Ends). The analyses of VfPIP1 transmembrane regions and amino acid sequence show that VfPIP1 owns six membrane-spanning domains and the special plasma membrane signature sequences GGGANXXXXGY and TGI/TNPARSL/FGAAI/VI/VF/YN, and it should be a member of PIP1 subfamily. The results of in situ hybridization and Northern blot indicate that VfPIP1 is strongly expressed in guard cells and induced by ABA. Hereby, VfPIP1 may be involved in the water-transmembrane movement of guard cells.

关键词： ABA aquaporin gene cloning Vicia faba guard cell.

Seasonal influence on the development of parthenotes and cloned embryos in pigs

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Progress in Natural science:Materials International 2007年第10期17卷 1172-1176页

作者： Zhang Kun1, Zhang Yunhai3,4, Pan Dengke5, Ma Yufang1, Wei Hengxi1, Zhang Jian6, Li Xuyang7, Wang Shaohua1, Li Yan2. Dai Yunping1,2.and Li Ning1(1. State Key Laboratory for Agrobiotechnology, college of biological {2., china agricultural university, beijing 100094, china 2. JiPulin Biotech Ltd., beijing 100094, china 3. Danish Institute of agricultural {2.s, 8830 Tjele, Denmark 4. college of Animal {2. and Technology, Anhui agricultural university, Hefei 2.0036, china 5. Institute of Animal {2.s, Chinese Academy of agricultural {2.s, beijing 100094, china 6. Animal Clinical Hospital, china agricultural university, beijing 100094, china 7. Hebei Minghui Group of Pigs Breeding, Sanhe 0652.0, china) State Key Laboratory for Agrobiotechnology College of Biological Science China Agricultural University Beijing 100094 China JiPulin Biotech Ltd. Beijing 100094 China Danish Institute of agricultural sciences 8830 Tjele Denmark college of Animal science and Technology Anhui Agricultural University Hefei 230036 China Institute of Animal sciences Chinese Academy of Agricultural Sciences Beijing 100094 China Animal Clinical Hospital China Agricultural University Beijing 100094 China 7. Hebei Minghui Group of Pigs Breeding Sanhe 065200 China

Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P<0.05). However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P<0.05). In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P<0.05), and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P<0.05). The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos.

关键词： pig cloned parthenogenetic season