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Research of blastocyte-like structure in chicken

Science china(Life Sciences) 2005年第5期48卷 481-486页

作者： LI Jia1, PAN Qiuzhen1, LI Junying1, HAN Hongbing1, SUN Shufeng1, YANG Jun1, XU Shuguang, TIAN Liang, LIAN Zhengxing1,2, YANG Ning1,2 & LI Ning2,3.1. College of Animal Science and Technology, china Agricultural University, beijing 100094, china 2. {3. of Animal Genetics and Breeding, Ministry of Agriculture, beijing 100094, china 3. state key laboratory of agrobiotechnology, beijing 100094, china 1. College of Animal Science and Technology China Agricultural University 100094 Beijing China 2. laboratory of Animal Genetics and Breeding Ministry of Agriculture 100094 Beijing China 3. state key laboratory of agrobiotechnology 100094 Beijing China

The chicken embryo is a classic model used to investigate embryonic development, gene expression, and tissue differentiation, and is also an important research tool in studying the animal functional genomics. The whole blastoderms of fresh unincubated eggs from White Leg-horn chickens were collected with a paper ring, mechanically broken into small pieces and cul-tured in medium. Then the small pieces would develop into blastocyte-like structures (BLS), which could be facilitated by an addition of fetal bovine serum (FBS) to the primary culture and their diameter was nearly doubled from 12 to 24 h. The additional yolk had no positive effect on the development in the first 12 h but encouraged the BLSs attaching and inner cells differentiat-ing instead in 24 h. The inner cells of the BLS showing a high alkaline-phosphatase activity similar to those in mouse embryonic stem (ES) cells and also expressing a large amount of the specific stage embryonic antigen-1 (SSEA-1) on the surface, which was known to be the char-acteristic of non-differentiated mouse and avian ES cells, could finally differentiate into nerve-like cells, fibroblast cells and so on in the medium. Leukemia inhibitory factor (LIF) facilitated the cells’ proliferation and prevented differentiation in the suspended culture of the BLSs. So we drew the conclusion that the BLS obtained from broken blastoderm can be used to amplify avian ES cells so as to initiate a new method of producing transgenic chickens.

关键词： BLS, blastocyst-like structure, embryonic stem cells, ES cells, chicken.

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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 {3., College of Biological Sciences, china Agricultural University, beijing 100094, china state key laboratory for {3. 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 Tn5-1063. 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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Measuring-basis-encrypted six-state quantum key distribution scheme

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Progress in Natural Science:Materials International 2006年第1期16卷 84-89页

作者： CHEN Pan1, DENG Fuguo1, WANG Pingxiao1 and LONG Guilu1,2 (key laboratory for Quantum Information and Measurements and Department of Physics, Tsinghua University, beijing 100084,{3. 2. key laboratory for Atomic and Molecular NanoSciences, Tsinghua University, beijing 100084,{3.) [a]Department of Physics Tsinghua University Key Laboratory for Quantum Information and Measurements Beijing China [b]Tsinghua University Key Laboratory for Atomic and Molecular NanoSciences Beijing China

A six-state quantum key distribution scheme with measuring-basis encryption technique, which is based on the six-state protocol and the MBE protocol, is proposed. In this modified six-state quantum key distribution protocol, Alice and Bob use a control key to synchronize the use of their measuring-basis so that they always use the same measuring-basis. This modified six-state quantum key distribution protocol retains the advantage of higher security and at the same time has a higher efficiency.

关键词： quantum key distribution measuring-basis encrypted six-state security.

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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, china Agricultural University, beijing 100094, china {3. key laboratory for agrobiotechnology, china Agricultural University, beijing 100094, china College of Animal Science and Technology China Agricultural University Beijing China state key laboratory for {3. 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.

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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 {3.,key laboratory of Crop Genomics and Genetic Improvement,Ministry of Agriculture/beijing key laboratory of Crop Genetic Improvement,china Agricultural University,beijing 100094,china [a]Department of Plant Genetics & Breeding and state key laboratory for {3. 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 3.1 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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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 {3. 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 11003., china 1. state key laboratory for {3. 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 3.4 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 10254 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.

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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 {3., 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 {3. 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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Genomic and genic sequence variation in synthetic hexaploid wheat (AABBDD) as compared to their parental species

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Progress in Natural Science:Materials International 2008年第5期18卷 533-538页

作者： Lihong Nie, Zongfu Han, Lahu Lu, Yingyin Yao, Qixin Sun, Zhongfu Ni key laboratory of Crop Heterosis and Utilization (MOE) and state key laboratory for agrobiotechnology, key laboratory of Crop Genomics and Genetic Improvement (MOA), 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 (MOE) and state key laboratory for agrobiotechnology Key Laboratory of Crop Genomics and Genetic Improvement (MOA) Beijing Key Laboratory of Crop Genetic Improvement Department of Plant Genetics & Breeding China Agricultural University Beijing 100094 China

In order to understand the genomic changes during the evolution of hexaploid wheat, two sets of synthetic hexaploid wheat from hybridization between maternal tetraploid wheat (AABB) and paternal diploid goat grass (DD) were used for DNA-AFLP and single strand conformation polymorphism (SSCP) analysis to determine the genomic and genic variation in the synthetic hexaploid wheat. Results indicated that more DNA sequences from paternal diploid species were eliminated in the synthetic hexaploid wheat than from maternal tetraploid wheat, suggesting that genome from parental species of lower ploidity tends to be eliminated preferentially. However, sequence variation detected by SSCP procedure was much lower than those detected by DNA-AFLP, which indicated that much less variation in the genic regions occurred in the synthetic hexaploid wheat, and sequence variations detected by DNA-AFLP could be derived mostly from non-coding regions and repetitive sequences. Our results also indicated that sequence variation in 4 genes can be detected in hybrid F1, which suggested that this type of sequence variation could be resulted from distant hybridization. It was interesting to note that 3.out of the 4 genes were mapped and clustered on the long arm of chromosome 2D, which indicated that variation in genic sequences in synthetic hexaploid wheat might not be a randomized process.

关键词： Synthetic hexaploid wheat Polyploidy Genome Sequence variation

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Research on applying physical chaos generator to spacecraft information security

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Science china(Technological Sciences) 2009年第5期52卷 1463-1470页

作者： ZHAO HePing state key laboratory of Information Security,Graduate University of Chinese Academy of Sciences,{3. 100049,china china Academy of Space Technology,{3. 100094,china state key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China china Academy of Space Technology Beijing 100094 China

The effectiveness of a short-length message extension method based on physical chaos generator was analyzed and the entropy of the extended message was calculated in this *** analysis demon-strated that with the mentioned method the entropy of short-length messages,which are repeatedly used in spacecraft data systems,is obviously increased,and the security of transmission is enhanced as *** paper also presented an improvement of the protocol for secret key agreement presented by *** and *** of depending on characteristics of communication channel,this method takes advantage of the random data produced by physical chaos generator to preset the initial parameters of the procedure on both sides of communication,so that the procedure and quantity of cipher key can be precisely *** method can be used to cipher key management of se-cure communication between long life-span spacecraft and ground system.

关键词： physical chaos generator spacecraft information security message extension cipher key management

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Cloning and expression profiles of 15 genes encoding WRKY transcription factor in wheat (Triticum aestivem L.)

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Progress in Natural Science:Materials International 2008年第6期18卷 697-705页

作者： Hualing Wu,Zhongfu Ni,Yingyin Yao,Ganggang Guo,Qixin Sun* Department of Plant Genetics&Breeding and state key laboratory for {3.,key laboratory of Crop Heterosis and Utilization,Ministry of Education,key laboratory of Crop Genomics and Genetic Improvement,Ministry of Agriculture/beijing key laboratory of Crop Genetic Improvement,china Agricultural University,beijing {13.,china Department of Plant Genetics & Breeding and state key laboratory for {3. Key Laboratory of Crop Heterosis and Utilization Ministry of Education Key Laboratory of Crop Genomics and Genetic Improvement Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement China Agricultural University Beijing 100094 China

WRKY proteins are involved in various physiological processes,including biotic and abiotic stress responses,hormone responses and ***,no systematic identification,expression and function analysis of WRKY genes in wheat were *** this study,we isolated 15 wheat cDNAs with complete open reading frame(ORF)encoding putative WRKY proteins using in silico *** analysis indicated that the 15 wheat WRKY genes belonged to three major WRKY *** analysis revealed that most genes expressed drastically in leaf,except TaWRKY10 which expressed in crown *** genes were strongly up-reg-ulated with the senescence of *** genes were responsive to low temperature,high temperature,NaCl or PEG ***-over,dierential expression patterns were also observed between wheat hybrid and its parents,and some genes were more responsive to PEG treatment in the *** results demonstrated that wheat WRKY genes are involved in leaf senescing and abiotic *** the changed expression of these WRKY genes in hybrid might contribute to the heterosis by improving the stress tolerance in hybrids.

关键词： Wheat WRKY transcription factor Gene cloning Gene expression Heterosis

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