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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,{2., 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 A2., 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.

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 state 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 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.

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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.

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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 {2. {2. of Animal Genetics, Breeding and Reproduction, china Agricultural University, beijing 100094, china) [a]College of Life Science and Technology Southwest University for Nationalities Chengdu China [b]state key laboratory for agrobiotechnology and Ministry of Agriculture key {2. of Animal Genetics Breeding and Reproduction China Agricultural University Beijing China

Milk epithelial mucin (MUC1) of yaks was separated by SDS-polyacrylamide gel electrophoresis. A total of nine types of MUC1 were revealed in 42. 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 2.8 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.

Cloning and characterization of an up-regulated GA 2.-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 {2. of Crop Genomics and Genetic Improvement,Ministry of Agriculture/{2. key {2. of Crop Genetic Improvement,china Agricultural University,{2. 100094,china [a]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 2.-oxidase gene in a maize hybrid,designated ZmGA2.,was cloned. ZmGA2. contains an open reading frame (ORF) encoding 391 amino acid residues. BLASTX searches in GenBank revealed that the ZmGA2. is homologous to the sequences of GA2.ox proteins from different species,and analysis also indicated that ZmGA2. had typical features of GA 2.-oxidase proteins,including a "LPWKET" sequence. Semi-quantitative RT-PCR analysis showed that ZmGA2. was expressed in different tissues and/or organs. The expression level of ZmGA2. in the hybrid was higher than that in two parents (in roots,leaves,stems and embryo,and ears). The abundance of ZmGA2. 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 2.-oxidase Gene expression Maize Heterosis

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,{2., china b beijing Gene & Protein Biotechnology Co. LTD,{2., china c College of Animal Science and Technology, china Agricultural University,{2., 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

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 {2., 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 {2. 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 2., 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

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 {2. of Information Security,Graduate University of Chinese Academy of Sciences,{2. 100049,china china Academy of Space Technology,{2. 100094,china state key {2. 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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Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1,2., ZHANG Shaowen~1 and LI Qianshu~1**(1. state key {2. of Explosion Science and Technology, {2. Institute of Technology, {2. 100081, china 2. {2. Institute of Education, {2. 100044, china) [a]state key {2. of Explosion Science and Technology Beijing Institute of Technology Beijing China [b]beijing Institute of Education Beijing China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

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 agrobiotechnology,key {2. of Crop Heterosis and Utilization,Ministry of Education,key {2. of Crop Genomics and Genetic Improvement,Ministry of Agriculture/beijing key {2. 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 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