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The Application of Nicotiana benthamiana as a Transient Expression Host to Clone the Coding Sequences of Plant Genes
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作者 Jianzhong Huang Peng Jia +3 位作者 Xiaoju Zhong Xiuying Guan Hongbin Zhang Honglei Ruan 《American Journal of Molecular Biology》 CAS 2024年第2期54-65,共12页
Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using co... Coding sequences (CDS) are commonly used for transient gene expression, in yeast two-hybrid screening, to verify protein interactions and in prokaryotic gene expression studies. CDS are most commonly obtained using complementary DNA (cDNA) derived from messenger RNA (mRNA) extracted from plant tissues and generated by reverse transcription. However, some CDS are difficult to acquire through this process as they are expressed at extremely low levels or have specific spatial and/or temporal expression patterns in vivo. These challenges require the development of alternative CDS cloning technologies. In this study, we found that the genomic intron-containing gene coding sequences (gDNA) from Arabidopsis thaliana, Oryza sativa, Brassica napus, and Glycine max can be correctly transcribed and spliced into mRNA in Nicotiana benthamiana. In contrast, gDNAs from Triticum aestivum and Sorghum bicolor did not function correctly. In transient expression experiments, the target DNA sequence is driven by a constitutive promoter. Theoretically, a sufficient amount of mRNA can be extracted from the N. benthamiana leaves, making it conducive to the cloning of CDS target genes. Our data demonstrate that N. benthamiana can be used as an effective host for the cloning CDS of plant genes. 展开更多
关键词 Coding sequence Genomic sequence Nicotiana benthamiana Plant Genes
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Pig pangenome graph reveals functional features of non‑reference sequences
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作者 Jian Miao Xingyu Wei +6 位作者 Caiyun Cao Jiabao Sun Yuejin Xu Zhe Zhang Qishan Wang Yuchun Pan Zhen Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期956-970,共15页
Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non... Background The reliance on a solitary linear reference genome has imposed a significant constraint on our compre-hensive understanding of genetic variation in animals.This constraint is particularly pronounced for non-reference sequences(NRSs),which have not been extensively studied.Results In this study,we constructed a pig pangenome graph using 21 pig assemblies and identified 23,831 NRSs with a total length of 105 Mb.Our findings revealed that NRSs were more prevalent in breeds exhibiting greater genetic divergence from the reference genome.Furthermore,we observed that NRSs were rarely found within coding sequences,while NRS insertions were enriched in immune-related Gene Ontology terms.Notably,our investigation also unveiled a close association between novel genes and the immune capacity of pigs.We observed substantial differences in terms of frequencies of NRSs between Eastern and Western pigs,and the heat-resistant pigs exhibited a substantial number of NRS insertions in an 11.6 Mb interval on chromosome X.Additionally,we discovered a 665 bp insertion in the fourth intron of the TNFRSF19 gene that may be associated with the ability of heat tolerance in South-ern Chinese pigs.Conclusions Our findings demonstrate the potential of a graph genome approach to reveal important functional features of NRSs in pig populations. 展开更多
关键词 Heat tolerance Immune ability Non-reference sequences Pig pangenome
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Phylogenetic, phylogeographic and divergence time analysis of Anopheles subpictus species complex using ITS2 and COI sequences
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作者 Lihini Sandaleka Muthukumarana Methsala Madurangi Wedage +1 位作者 Samanthika Rathnayake Nissanka Kolitha De Silva 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第5期214-225,I0004-I0038,共47页
Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Tran... Objective:To address the phylogenetic and phylogeographic relationship between different lineages of Anopheles(An.)subpictus species complex in most parts of the Asian continent by maximum utilization of Internal Transcriber Spacer 2(ITS2)and cytochrome C oxidase I(COI)sequences deposited at the GenBank.Methods:Seventy-five ITS2,210 COI and 26 concatenated sequences available in the NCBI database were used.Phylogenetic analysis was performed using Bayesian likelihood trees,whereas median-joining haplotype networks and time-scale divergence trees were generated for phylogeographic analysis.Genetic diversity indices and genetic differentiation were also calculated.Results:Two genetically divergent molecular forms of An.subpictus species complex corresponding to sibling species A and B are established.Species A evolved around 37-82 million years ago in Sri Lanka,India,and the Netherlands,and species B evolved around 22-79 million years ago in Sri Lanka,India,and Myanmar.Vietnam,Thailand,and Cambodia have two molecular forms:one is phylogenetically similar to species B.Other forms differ from species A and B and evolved recently in the above mentioned countries,Indonesia and the Philippines.Genetic subdivision among Sri Lanka,India,and the Netherlands is almost absent.A substantial genetic differentiation was obtained for some populations due to isolation by large geographical distances.Genetic diversity indices reveal the presence of a long-established stable mosquito population,at mutation-drift equilibrium,regardless of population fluctuations.Conclusions:An.subpictus species complex consists of more than two genetically divergent molecular forms.Species A is highly divergent from the rest.Sri Lanka and India contain only species A and B. 展开更多
关键词 Molecular systematics ITS2 COI DNA sequences Phylogeny PHYLOGEOGRAPHY
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On power series statistical convergence and new uniform integrability of double sequences
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作者 Sevda Y■ld■z Kamil Demirci 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第3期519-532,共14页
In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p... In the present paper,we mostly focus on P_(p)^(2)-statistical convergence.We will look into the uniform integrability via the power series method and its characterizations for double sequences.Also,the notions of P_(p)^(2)-statistically Cauchy sequence,P_(p)^(2)-statistical boundedness and core for double sequences will be described in addition to these findings. 展开更多
关键词 power series methods statistical convergence uniform integrability double sequences
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Secure Transmission of Compressed Medical Image Sequences on Communication Networks Using Motion Vector Watermarking
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作者 Rafi Ullah Mohd Hilmi bin Hasan +1 位作者 Sultan Daud Khan Mussadiq Abdul Rahim 《Computers, Materials & Continua》 SCIE EI 2024年第3期3283-3301,共19页
Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all whil... Medical imaging plays a key role within modern hospital management systems for diagnostic purposes.Compression methodologies are extensively employed to mitigate storage demands and enhance transmission speed,all while upholding image quality.Moreover,an increasing number of hospitals are embracing cloud computing for patient data storage,necessitating meticulous scrutiny of server security and privacy protocols.Nevertheless,considering the widespread availability of multimedia tools,the preservation of digital data integrity surpasses the significance of compression alone.In response to this concern,we propose a secure storage and transmission solution for compressed medical image sequences,such as ultrasound images,utilizing a motion vector watermarking scheme.The watermark is generated employing an error-correcting code known as Bose-Chaudhuri-Hocquenghem(BCH)and is subsequently embedded into the compressed sequence via block-based motion vectors.In the process of watermark embedding,motion vectors are selected based on their magnitude and phase angle.When embedding watermarks,no specific spatial area,such as a region of interest(ROI),is used in the images.The embedding of watermark bits is dependent on motion vectors.Although reversible watermarking allows the restoration of the original image sequences,we use the irreversible watermarking method.The reason for this is that the use of reversible watermarks may impede the claims of ownership and legal rights.The restoration of original data or images may call into question ownership or other legal claims.The peak signal-to-noise ratio(PSNR)and structural similarity index(SSIM)serve as metrics for evaluating the watermarked image quality.Across all images,the PSNR value exceeds 46 dB,and the SSIM value exceeds 0.92.Experimental results substantiate the efficacy of the proposed technique in preserving data integrity. 展开更多
关键词 Block matching algorithm(BMA) compression full-search algorithm motion vectors ultrasound image sequence WATERMARKING
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Molecular Phylogeny of the Lardizabalaceae Based on TrnL-F Sequences and Combined Chloroplast Data 被引量:5
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作者 王峰 李德铢 杨俊波 《Acta Botanica Sinica》 CSCD 2002年第8期971-977,共7页
The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and... The molecular phylogeny of the Lardizabalaceae is reconstructed based on chloroplast trn L_F sequences alone and combined trn L_F and rbc L sequences. The phylogenetic topologies agree well with Qin's and Takhtajan's tribal classification in both analyses. Decaisneae and Sinofranchetieae are basal clades in the phylogenetic trees and external to all other taxa in the family. Lardizabaleae consisting of Boquila and Lardizabala are well supported in both trn L_F (100%) analysis and trn L_F and rbc L combined analysis (99%). Tribe Akebieae are strongly supported by a bootstrap value of 100% in both trn L_F analysis and trn L_F and rbc L combined analysis. However, the new genus Archakebia is nested within the genus Akebia in the trn L_F trees. In the combined trees, Archakebia is sister to Akebia with high bootstrap support. The inter_relationships among three closely related genera Parvatia , Holboellia and Stauntonia are still problematic. P. brunoniana ssp. elliptica is sister to H. latifolia in both analyses with low bootstrap support. H. parviflora is nested within the Stauntonia and sister to S. cavalerieana . Therefore, these three genera of tribe Akebieae may not be monophylytic and their generic boundary and delimitation need to be further studied, by exploring more molecular data, together with more morphological characters. 展开更多
关键词 LARDIZABALACEAE molecular phylogeny trn L_F sequences rbc L sequences
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ITS1 SEQUENCES OF NUCLEAR RIBOSOMAL DNA IN WILD RICES AND CULTIVATED RICES OF CHINA AND THEIR PHYLOGENETIC IMPLICATIONS 被引量:22
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作者 周毅 邹喻苹 +2 位作者 洪德元 周骏马 陈受宜 《Acta Botanica Sinica》 CSCD 1996年第10期785-791,共7页
The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced wi... The first internal transcribed spacer(ITS1) of nuclear ribosomal DNA of three wild rice species and two subspecies of cultivated rice, which are distributed in China, was amplified using PCR technique and sequenced with automated fluorescent sequencing. The sequences of ITS1 ranged from 193 bp to 218 bp in size and G/C content varied from 69.3% to 72.7%. In pairwise comparisons among the five taxa, sequence site divergence ranged from 1.5% to 10.6%. Phylogenetic analysis of ITS1 sequences using Wagner parsimony generated a single well resolved tree, which revealed that Oryza rufipogon was much more closely related to cultivated rice species than to the other two wild species. Oryza granulata was less closely related to either cultivated rice species or the other two wild species, and might be a unique and isolated taxon in the genus Oryza. The phylogenetic relationships of the three wild rice species and two cultivated rice subspecies inferred from ITS1 sequences is highly concordant with those based on the molecular evidence from isozyme, chloroplast DNA (cpDNA), mitochondrial DNA(mtDNA) and nuclear DNA (nDNA) of the genus Oryza . 展开更多
关键词 Wild rice Cultivated rice ITS1 of rDNA sequence analysis PHYLOGENY
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Characterization of Two Groups of Low_copy and Specific DNA Sequences Isolated from Chromosome 7B of Common Wheat 被引量:2
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作者 刘振兰 董玉柱 刘宝 《Acta Botanica Sinica》 CSCD 2002年第8期946-950,共5页
Recent work revealed that, in the genomes of polyploid wheat, there exists a class of low_copy and chromosome_specific sequences that are labile upon polyploid formation. This class of sequences was proposed to play ... Recent work revealed that, in the genomes of polyploid wheat, there exists a class of low_copy and chromosome_specific sequences that are labile upon polyploid formation. This class of sequences was proposed to play a critical role in the stabilization and establishment of nascent plant polyploids as new species. To further study this issue, five wheat chromosome 7B_specific sequences, isolated from common wheat (Triticum aestivum L.) by chromosome microdissection, were characterized. The sequences were studied by genomic Southern hybridizations on a collection of polyploid wheats and their diploid progenitors. Four sequences hybridized to all polyploid species, but at the diploid level to only species closely related to the B_genome of polyploid wheat. This indicates that these sequences originated with the divergence of the diploid species, and was then vertically transmitted to polyploids. One sequence hybridized to all species at both the diploid and polyploid levels, suggesting its elimination after the polyploid wheat formation. The hybridization of this sequence to two synthetic polyploid wheats indicated that sequence elimination is a rapid event and probably related to methylation status of the sequence. Based on the above results, we suggest that selective changes of low_copy sequences occur rapidly after polyploid formation, which may contribute to the differentiation of chromosomes in newly formed allopolyploid wheats. 展开更多
关键词 polyploid wheat chromosome_specific DNA sequences sequence elimination DNA methylation genome evolution
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Isolation of Zizania latifolia Species-specific DNA Sequences and Their Utility in Identification of Z. latifolia DNA Introgressed into Rice 被引量:5
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作者 刘振兰 董玉柱 刘宝 《Acta Botanica Sinica》 CSCD 2000年第3期324-326,共3页
根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)Turcz.exStapf... 根据两个植物抗病基因N和RPS2中核酸结合位点 (NBS)和富亮氨酸重复区 (LRR)中的保守序列设计了一对特异引物 ,用PCR从具有水稻 (OryzasativaL .)改良所需要的许多优良性状的水稻近缘野生种菰 (Zizanialatifolia(Griseb .)Turcz.exStapf)的基因组DNA中扩增同源片段。PCR产物经克隆后 ,分别以菰和水稻的基因组DNA为探针 ,通过点杂交对所得克隆进行了分析。点杂交结果表明 ,在所分析的 6 0个克隆中有 2个克隆是菰专化的序列 ,即它们与水稻无杂交信号。基因组DNA的Southern杂交进一步证实了这 2个克隆的专化性。为了验证一些可能的“水稻_菰”渐渗杂交系是否确实含有源自供体菰的DNA ,以这 2个克隆为探针 ,与经EcoRⅠ酶切的 5个可能的渐渗杂交系进行了Southern杂交。结果表明 ,这 2个克隆均能检测出其中的一个系含有其同源序列。这一结果为曾经报道的经一种非常规有性杂交方法将菰DNA导入水稻提供了确凿的证据。 展开更多
关键词 species_specific DNA sequence introgression lines Zizania latifolia RICE
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MINER RULE CONSIDERING FUZZINESS OF STRESS DAMAGE UNDER DIFFERENT LOAD SEQUENCES 被引量:7
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作者 王旭亮 聂宏 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第3期182-186,共5页
Since the traditional Miner rule ignores the influence of the load sequence on the fatigue life, the fuzzy rules are used to analyze the fuzziness of the fatigue damage caused by the stress nearby the fatigue limit un... Since the traditional Miner rule ignores the influence of the load sequence on the fatigue life, the fuzzy rules are used to analyze the fuzziness of the fatigue damage caused by the stress nearby the fatigue limit under different load sequences. The improved fuzzy Miner rule can reflect the influence of the load sequence on the fatigue life. Results of the example show that the prediction error can be reduced from 61.6% to 21.7%. 展开更多
关键词 atigue damage fuzzy rules membership functions load sequence Miner rule
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Classification and Identification of Marine Penicillium Species Based on ITS Sequences of rDNA 被引量:3
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作者 曲凌云 田黎 孙修勤 《Agricultural Science & Technology》 CAS 2009年第4期101-104,共4页
[ Objective ] The aim of this study is to identify 6 marine fungi species by analyzing ITS nucleotide sequence, which had been primarily identified as penicillium based on morphological characteristics. [ Method ] The... [ Objective ] The aim of this study is to identify 6 marine fungi species by analyzing ITS nucleotide sequence, which had been primarily identified as penicillium based on morphological characteristics. [ Method ] The ITS regions of these species were cloned by molecule biology method and phylogenetic analyzed using ClustalX1.83 software. [ Result] The ITS regions of these species were sequenced, and phylogenetic analysis between the yield sequences and the ITS sequences assessed in GenBank showed that the 6 strains all belonged to penicillium. [ Condusion] The present study suggests ITS sequence analysis could not be used as an only proof, but it is a very useful supplementary tool for the classification and identification of marine peniciUium combined with morphological characteristics. 展开更多
关键词 Marine penicillium ITS sequence Phylogenetic analysis
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Phylogenetic Relationships of Caragana(Fabaceae) by the Use of nrITS Sequences 被引量:2
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作者 康红梅 白娟 +1 位作者 陈康 王刚 《Agricultural Science & Technology》 CAS 2012年第1期36-39,共4页
[Objective] The aim was to explore the phylogenetic relationships of Cara- gana (Fabaceae) by the use of nrlTS sequences. [Method] Internal transcribed spac- er (ITS) sequences of nuclear ribosomal DNA (nrDNA) f... [Objective] The aim was to explore the phylogenetic relationships of Cara- gana (Fabaceae) by the use of nrlTS sequences. [Method] Internal transcribed spac- er (ITS) sequences of nuclear ribosomal DNA (nrDNA) from 29 taxa of Caragana species and seven close relatives (all belong to Astralinae (Adens) Benth) were used for phylogenetic analysis. [Result] Length of the entire ITS region ranges from 611 to 614 bp in Caragana species. The aligned sequences nrlTS of Caragana are 655 bp, and 170 sites are variable, with 107 phylogenetically informative sites. The phylogenetically informative sites are 16.3% of the total aligned sequences. The ITS sequences data are useful to resolve some relationships at lower taxonomic levels within Caragana. The Caragana Fabr. is not a monophyletic group with very close connection with Calophaca tianschanica. The ITS data revealed that the species of Sect. tragacanthoides were dispersed in MP tree or ME tree. Although the morphol- ogy of C. ordosica is similar to C. tibetica, the ITS results revealed an unexpectedly close relativeship to C. roborovskyi. The ITS data also indicate C. davazamcii, C. korshinskii, C. intermedia, and C. microphylla are different species. [Conclusion] ITS sequences have an important reference value in exploring the relationships of Cara- gana. 展开更多
关键词 Caragana Fabr. ITS sequence Phylogenetic relationships
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SECURITY ANALYSIS BASED ON OVERSAMPLED CHAOTIC BINARY SEQUENCES 被引量:1
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作者 张宏涛 王慧云 丁润涛 《Transactions of Tianjin University》 EI CAS 2001年第2期123-126,共4页
Some chaotic sequences generated from maps conjugated with tent map can be reconstructed precisely by short sequence prediction,since the problem of finite precision degrades the statistical properties of chaotic ma... Some chaotic sequences generated from maps conjugated with tent map can be reconstructed precisely by short sequence prediction,since the problem of finite precision degrades the statistical properties of chaotic maps.This paper discusses the topological conjugation properties of the chaotic maps;analyzes in detail the reconstruction process of the chaotic sequences and the security of the oversampled chaotic map (OSCM) binary sequences.The result demonstrates that OSCM binary sequences can sustain the attack of the short sequence prediction,that is,they cant be reconstructed.Furthermore,all attack strategies aiming at the chaotic systems based on synchronization will fail,meaning that they are secure. 展开更多
关键词 SECURITY OSCM sequences topological conjugation
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Cloning and Expression of Conserved Sequences of cry Gene in E.coli Strain Rosetta(DE3) 被引量:1
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作者 罗翠平 李金华 +1 位作者 谢烨明 曾万勇 《Agricultural Science & Technology》 CAS 2012年第5期958-961,996,共5页
[Objective] The aim was to clone the conserved sequences of cry gene and express them in Rosetta (DE3). [Method] Specific primers were designed according to NCBI database information and the conserved sequences of c... [Objective] The aim was to clone the conserved sequences of cry gene and express them in Rosetta (DE3). [Method] Specific primers were designed according to NCBI database information and the conserved sequences of cry gene were amplified by PCR from Bt transgenic cotton. Then recombinant plasmids were constructed and expressed in E. coil strain Rosetta (DE3). Finally, the effects of different concentrations and inducing time of IPTG on the expression level of protein were investigated. [Result] Two conserved sequences (304 and 853 bp respectively) of cry gene were amplified. The result of SDS-PAGE confirmed that the recombinant plasmids pGEX-4t-I-304 and pGEX-4t-1-853 could express fusion proteins by IPTG induction and the molecular weight of protein products was 39 and 62.4 kDa respectively, which was in accordance with predicted result. The optimal protein ex- pression conditions were confirmed as induction with 0.15 mmol/L IPTG for 7 h. [Conclusion] This study prepared the ground for the further detection of Bt transgenic crops. 展开更多
关键词 Bt gene Conserved sequence CLONING Prokaryotic expression
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Isolation of the Flanking Sequences Adjacent to Transgenic T-DNA in Brassica napus Genome by an Improved Inverse PCR Method 被引量:2
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作者 杨坤 吴学龙 +1 位作者 朗春秀 陈锦清 《Agricultural Science & Technology》 CAS 2010年第2期65-68,139,共5页
[Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the ... [Objective] The research aimed to isolate flanking sequences adjacent to the transgenic T-DNA in Brassica napus by an improved inverse PCR method.[Method] Using single clone of transgenic FS4 in Brassica napus as the research materials,total DNA was extracted from transgenic Brassica napus by using modified CTAB method.After enzyme digestion and purification,self-joining was made.Two circles of nested PCR and the sequence alignment were carried out.[Result] A fragement with the size of 4.0 kb was amplified ... 展开更多
关键词 Inverse PCR(IPCR) Flanking sequences Improved CTAB method Transgenic Brassica napus
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Microdissection of Haynaldia villosa Telosome 6VS and Cloning of Species-specific DNA Sequences 被引量:3
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作者 孔凡晶 陈孝 +4 位作者 马有志 辛志勇 李连成 张增艳 林志姗 《Acta Botanica Sinica》 CSCD 2002年第3期307-313,共7页
The material T240_6 derived from SC 2 young embryo of the combination CA9211/RW15 (6D/6V alien substitution) was telosomic substitution line of 6VS identified by GISH (genomic in situ hybridization) analysis. The 6V... The material T240_6 derived from SC 2 young embryo of the combination CA9211/RW15 (6D/6V alien substitution) was telosomic substitution line of 6VS identified by GISH (genomic in situ hybridization) analysis. The 6VS was microdissected with a needle and transferred into a 0.5 mL Ep tube. In the 'single tube', all the subsequence steps were conducted. After two round of LA (Linker adaptor)_PCR amplification, the size of PCR bands ranged from 100 to 3 000 bp, with predominate bands 600-1 500 bp. The products were confirmed by Southern blotting analysis using Haynaldia villosa (L.) Schur. genomic DNA labeled with 32 P as probe. The PCR products were purified and ligated into clone vector-pGEM_T easy vector. Then, the plasmids were transformed into competence E. coli JM109 with cool CaCl 2. It was estimated that there were more than 17 000 white clones in the library. The size of insert fragments distributed from 100-1 500 bp, with average of 600 bp. Using H. villosa genomic DNA as probe, dot blotting results showed that 37% clones displayed strong and medium positive signals, and 63% clones had faint or no signals. It is demonstrated that there were about 37% repeat sequence clones and 67% single/unique sequence clones in the library. Eight H. villosa_specific clones were screened from the library, and two clones pHVMK22 and pHVMK134 were used for RFLP analysis and sequencing. Both of them were H. villosa specific clones. The pHVMK22 was a unique sequence clone, and the pHVMK134 was a repeat sequence clone. When the pHVMK22 was used as a probe for Southern hybridization, all the powdery mildew resistance materials showed a special band of 2 kb, while all the susceptible ones not. The pHVMK22 may be applied to detect the existence of Pm21. 展开更多
关键词 microdissection and microcloning of chromosome Haynaldia villosa genomic in situ hybridization alien substitution of telosome species_specific DNA sequences RFLP
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Preliminary Study on the ITS Sequences of nrDNA from Rhodiola alsia
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作者 高庆波 张得钧 +2 位作者 段义忠 张发起 陈世龙 《Agricultural Science & Technology》 CAS 2008年第5期63-65,149,共4页
[Objective] The study aimed to analyze the ITS sequences of nrDNA from Rhodiola alisa and investigate the difference of evolution rate between nrDNA and trnS-trnG and rpl20-rps12 sequences of cpDNA(chloroplast DNA).[M... [Objective] The study aimed to analyze the ITS sequences of nrDNA from Rhodiola alisa and investigate the difference of evolution rate between nrDNA and trnS-trnG and rpl20-rps12 sequences of cpDNA(chloroplast DNA).[Method]Total DNA was extracted from silica-dried leaves of R.alsia by using modified CTAB method.With the extracted DNA sample as template,nrDNA ITS region was amplified,then purified and sequenced.In addition,the yielded ITS sequences were also compared with the known trnS-trnG and rpl20-rps12 sequences of cpDNA from R.alsia.[Result]The ITS sequence of nrDNA from R.alsia was 701 bp in length,of which 13 variable sites were found with a percentage of 1.85%.Of the 13 variable sites,8 were caused by point mutations,5 were the results of insertions or deletions.The(A+T)content and(G+C)content were 46.9% and 53.1%,respectively.The nucleotide diversity(π)was 0.004 27.[Conclusion]The ITS region of nrDNA from R.alsia was more conservative and evolved more slowly than the trnS-trnG and rpl20-rps12 sequences of its cpDNA. 展开更多
关键词 RHODIOLA alsia ITS sequencE trnS-trnG sequencE rpl20-rps12 sequencE
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Characteristic atom sequences of Nb-Mo alloys system in BCC structure and properties of disordered alloys
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作者 彭红建 武青 +1 位作者 李小波 谢佑卿 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第5期1190-1196,共7页
Comprehensively considering energy, volume and electronic structure of alloys, the ninth equation was determined as the interaction function of Nb-Mo alloys system in BCC structure on the basis of idea of systematic s... Comprehensively considering energy, volume and electronic structure of alloys, the ninth equation was determined as the interaction function of Nb-Mo alloys system in BCC structure on the basis of idea of systematic science of alloys, experimental lattice constants and heats of formation of disordered Nb(1-x)Mox alloys. The structural parameters and properties of Nb and Mo characteristic atoms sequences and corresponding characteristic crystals sequences were determined in Nb-Mo alloys system. The electronic structure and physical properties of disordered Nb(1-x)Mox alloys system were calculated according to concentration of characteristic atoms of disordered alloys. The change trend of physical properties is the same as that of electronic structure. 展开更多
关键词 Nb-Mo alloys system characteristic atom sequences disordered alloys properties
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Auto-selection order of Markov chain for background sequences with chi-square test
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作者 谢雪英 孙啸 陆祖宏 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期311-316,共6页
Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher ... Modeling non coding background sequences appropriately is important for the detection of regulatory elements from DNA sequences. Based on the chi square statistic test, some explanations about why to choose higher order Markov chain model and how to automatically select the proper order are given in this paper. The chi square test is first run on synthetic data sets to show that it can efficiently find the proper order of Markov chain. Using chi square test, distinct higher order context dependences inherent in ten sets of sequences of yeast S.cerevisiae from other literature have been found. So the Markov chain with higher order would be more suitable for modeling the non coding background sequences than an independent model. 展开更多
关键词 non coding sequences regulatory elements chi square test Markov chain
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Sequencing and Analysis of ITS Sequences of Bangia atropurpurea
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作者 李峰 冯佳 谢树莲 《Agricultural Science & Technology》 CAS 2010年第9期45-46,192,共3页
[Object]To providing new data for phylogenesis of Bangia atropurpurea by the sequencing of internal transcribed spacer(ITS region)of rDNA.[Method]B.atropurpurea was collected from Niangziguan Spring in Shanxi,the DN... [Object]To providing new data for phylogenesis of Bangia atropurpurea by the sequencing of internal transcribed spacer(ITS region)of rDNA.[Method]B.atropurpurea was collected from Niangziguan Spring in Shanxi,the DNA was extracted and the primers were designed for PCR amplification so as to obtain ITS gene sequence.[Result]The homology of ITS region between B.atropurpurea and Porphyra oligospermatangia was 75%,which was 79% between B.atropurpurea and P.yezoensis.[Conclusion]Compared with other genes,the ITS sequence had a greater evolution rate.The differences in classification and distribution resulted in the sequence diversity. 展开更多
关键词 Bangia atropurpurea ITS1-5.8SrDNA-ITS2 sequencE
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