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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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Landscape of Sequence Variations in Homologous Copies of FAD2 and FAD3 in Rapeseed(Brassica napus L.)Germplasm with High/Low Linolenic Acid Trait
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作者 Haoxue Wu Xiaohan Zhang +5 位作者 Xiaoyu Chen Kang Li Aixia Xu Zhen Huang Jungang Dong Chengyu Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期627-640,共14页
Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har... Genetic manipulation(either restraint or enhancement)of the biosynthesis pathway ofα-linolenic acid(ALA)in seed oil is an important goal in Brassica napus breeding.B.napus is a tetraploid plant whose genome often har-bors four and six homologous copies,respectively,of the two fatty acid desaturases FAD2 and FAD3,which con-trol the last two steps of ALA biosynthesis during seed oil accumulation.In this study,we compared their promoters,coding sequences,and expression levels in three high-ALA inbred lines 2006L,R8Q10,and YH25005,a low-ALA line A28,a low-ALA/high-oleic-acid accession SW,and the wildtype ZS11.The expression levels of most FAD2 and FAD3 homologs in the three high-ALA accessions were higher than those in ZS11 and much higher than those in A28 and SW.The three high-ALA accessions shared similar sequences with the pro-moters and CDSs of BnFAD3.C4 and BnFAD3.A3.In A28 and SW,substitution of three amino acid residues in BnFAD2.A5 and BnFAD2.C5,an absence of BnFAD2.C1 locus,and a 549 bp long deletion on the BnFAD3.A3 promoter were detected.The profile of BnFAD2 mutation in the two low-ALA accessions A28 and SW is different from that reported in previous studies.The mutations in BnFAD3 in the high-ALA accessions are reported for thefirst time.In identifying the sites of these mutations,we provide detailed information to aid the design of mole-cular markers for accelerated breeding schemes. 展开更多
关键词 Brassica napus linolenic acid FAD2 FAD3 promoter coding sequences mutation
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东北马鹿ELK1基因CDS序列克隆及其生物信息学分析
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作者 武世瑶 罗兆聪 +5 位作者 高仰 韩青 索靖媛 金庆梅 郑冬 刘学东 《黑龙江畜牧兽医》 CAS 北大核心 2023年第9期116-120,134,共6页
为探究东北马鹿ELK1基因CDS序列信息,试验进行了mRNA反转录、CDS序列扩增,测定ELK1基因CDS序列,克隆并构建蛋白表达载体,利用生物信息学方法对该基因编码的蛋白质结构及理化性质等进行了预测与分析。结果表明:东北马鹿ELK1基因转录产物... 为探究东北马鹿ELK1基因CDS序列信息,试验进行了mRNA反转录、CDS序列扩增,测定ELK1基因CDS序列,克隆并构建蛋白表达载体,利用生物信息学方法对该基因编码的蛋白质结构及理化性质等进行了预测与分析。结果表明:东北马鹿ELK1基因转录产物CDS序列全长为1323 bp(GenBank登录号为ON212657),编码440个氨基酸,分子量为46200.42 u。核酸序列具有进化保守性,与牛ELK1基因同源性最高,为97.99%。ELK1多肽链具有亲水性,没有分泌信号肽结构,等电点为5.81,蛋白质为不稳定蛋白。ELK1蛋白的二级结构由无规则卷曲、α-螺旋、延伸链、β-折叠组成,存在ETS DNA结合域,亚细胞定位于细胞核。 展开更多
关键词 马鹿 鹿茸 软骨 ELK1 cds序列 生物信息学分析
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Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern 被引量:4
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作者 WANG Zhi1, 2, WU Li-xin1, 2, LI Hui-ying3 1. College of Resources and Civil Engineering, Northeastern University, Shenyang 110004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 100875, China 3. College of Computer Science and Technology, Jilin University, Changchun 130012, China 《中国有色金属学会会刊:英文版》 CSCD 2011年第S3期570-576,共7页
Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navi... Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3D scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3D mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom. 展开更多
关键词 LIDAR CODED sequence pattern mobile POSITIONING SLAM ALGORITHM POSIT ALGORITHM
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The structural analysis of protein sequences based on the quasi-amino acids code 被引量:2
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作者 朱平 唐旭清 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期363-369,共7页
Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper stud... Proteomics is the study of proteins and their interactions in a cell. With the successful completion of the Human Cenome Project, it comes the postgenome era when the proteomics technology is emerging. This paper studies protein molecule from the algebraic point of view. The algebraic system (∑, +, *) is introduced, where ∑ is the set of 64 codons. According to the characteristics of (∑, +, *), a novel quasi-amino acids code classification method is introduced and the corresponding algebraic operation table over the set ZU of the 16 kinds of quasi-amino acids is established. The internal relation is revealed about quasi-amino acids. The results show that there exist some very close correlations between the properties of the quasi-amino acids and the codon. All these correlation relationships may play an important part in establishing the logic relationship between codons and the quasi-amino acids during the course of life origination. According to Ma F et al (2003 J. Anhui Agricultural University 30 439), the corresponding relation and the excellent properties about amino acids code are very difficult to observe. The present paper shows that (ZU, +,×) is a field. Furthermore, the operational results display that the eodon tga has different property from other stop codons. In fact, in the mitochondrion from human and ox genomic codon, tga is just tryptophane, is not the stop codon like in other genetic code, it is the case of the Chen W C et al (2002 Acta Biophysiea Siniea 18(1) 87). The present theory avoids some inexplicable events of the 20 kinds of amino acids code, in other words it solves the problem of 'the 64 codon assignments of mRNA to amino acids is probably completely wrong' proposed by Yang (2006 Progress in Modern Biomedicine 6 3). 展开更多
关键词 algebraic operation quasi-amino acids code protein sequences structural analysis
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GAUSS PERIODS AND CYCLIC CODES FROM CYCLOTOMIC SEQUENCES OF SMALL ORDERS 被引量:1
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作者 Hu Liqin Yue Qin Zhu Xiaomeng 《Journal of Electronics(China)》 2014年第6期537-546,共10页
Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, severa... Let p =ef +1 be an odd prime with positive integers e and f. In this paper, we calculate the values of Gauss periods of order e =3, 4, 6 over a finite field GF(q), where q is a prime with q≠p. As applications, several cyclotomic sequences of order e =3, 4, 6 are employed to construct a number of classes of cyclic codes over GF(q) with prime length. Under certain conditions, the linear complexity and reciprocal minimal polynomials of cyclotomic sequences are calculated, and the lower bounds on the minimum distances of these cyclic codes are obtained. 展开更多
关键词 sequence Cyclic code Weight distribution Gauss period CYCLOTOMY
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A reduced computational load protein coding predictor using equivalent amino acid sequence of DNA string with period-3 based time and frequency domain analysis 被引量:1
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作者 Jayakishan K. Meher Gananath N. Dash +1 位作者 Pramod Kumar Meher Mukesh Kumar Raval 《American Journal of Molecular Biology》 2011年第2期79-86,共8页
Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein codi... Development of efficient gene prediction algorithms is one of the fundamental efforts in gene prediction study in the area of genomics. In genomic signal processing the basic step of the identification of protein coding regions in DNA sequences is based on the period-3 property exhibited by nucleotides in exons. Several approaches based on signal processing tools and numerical representations have been applied to solve this problem, trying to achieve more accurate predictions. This paper presents a new indicator sequence based on amino acid sequence, called as aminoacid indicator sequence, derived from DNA string that uses the existing signal processing based time-domain and frequency domain methods to predict these regions within the billions long DNA sequence of eukaryotic cells which reduces the computational load by one-third. It is known that each triplet of bases, called as codon, instructs the cell machinery to synthesize an amino acid. The codon sequence therefore uniquely identifies an amino acid sequence which defines a protein. Thus the protein coding region is attributed by the codons in amino acid sequence. This property is used for detection of period-3 regions using amino acid sequence. Physico-chemical properties of amino acids are used for numerical representation. Various accuracy measures such as exonic peaks, discriminating factor, sensitivity, specificity, miss rate, wrong rate and approximate correlation are used to demonstrate the efficacy of the proposed predictor. The proposed method is validated on various organisms using the standard data-set HMR195, Burset and Guigo and KEGG. The simulation result shows that the proposed method is an effective approach for protein coding prediction. 展开更多
关键词 GENOMICS Bioinformatics CODON coding region Amino Acid sequence Fourier Transform Antinotch Filter Periodicity-3 Indicator sequence
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Single cell RNA sequencing reveals mesenchymal heterogeneity and critical functions of Cd271 in tooth development
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作者 Yan-Yan Zhang Feng Li +6 位作者 Xiao-Ke Zeng Yan-Hui Zou Bing-Bing Zhu Jia-Jia Ye Yun-Xiao Zhang Qiu Jin Xin Nie 《World Journal of Stem Cells》 SCIE 2023年第6期589-605,共17页
BACKGROUND Accumulating evidence suggests that the maxillary process,to which cranial crest cells migrate,is essential to tooth development.Emerging studies indicate that Cd271 plays an essential role in odontogenesis... BACKGROUND Accumulating evidence suggests that the maxillary process,to which cranial crest cells migrate,is essential to tooth development.Emerging studies indicate that Cd271 plays an essential role in odontogenesis.However,the underlying mechanisms have yet to be elucidated.AIM To establish the functionally heterogeneous population in the maxillary process,elucidate the effects of Cd271 deficiency on gene expression differences.METHODS p75NTR knockout(Cd271-/-)mice(from American Jackson laboratory)were used to collect the maxillofacial process tissue of p75NTR knockout mice,and the wildtype maxillofacial process of the same pregnant mouse wild was used as control.After single cell suspension,the cDNA was prepared by loading the single cell suspension into the 10x Genomics Chromium system to be sequenced by NovaSeq6000 sequencing system.Finally,the sequencing data in Fastq format were obtained.The FastQC software is used to evaluate the quality of data and CellRanger analyzed the data.The gene expression matrix is read by R software,and Seurat is used to control and standardize the data,reduce the dimension and cluster.We search for marker genes for subgroup annotation by consulting literature and database;explore the effect of p75NTR knockout on mesenchymal stem cells(MSCs)gene expression and cell proportion by cell subgrouping,differential gene analysis,enrichment analysis and protein-protein interaction network analysis;understand the interaction between MSCs cells and the differentiation trajectory and gene change characteristics of p75NTR knockout MSCs by cell communication analysis and pseudo-time analysis.Last we verified the findings single cell sequencing in vitro.RESULTS We identified 21 cell clusters,and we re-clustered these into three subclusters.Importantly,we revealed the cell–cell communication networks between clusters.We clarified that Cd271 was significantly associated with the regulation of mineralization.CONCLUSION This study provides comprehensive mechanistic insights into the maxillary-process-derived MSCs and demonstrates that Cd271 is significantly associated with the odontogenesis in mesenchymal populations. 展开更多
关键词 cd271 Mesenchymal stem cells Single cell RNA sequencing OSTEOGENESIS MINERALIZATION Tooth development
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QUASI-SYNCHRONOUS MULTICARRIER DS-CDMA USING Z-COMPLEMENTARY SEQUENCES 被引量:1
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作者 Tu Yifeng Fan Pingzhi +1 位作者 Yuan Weina Hao Li 《Journal of Electronics(China)》 2009年第4期487-491,共5页
In this paper, a multicarrier DS-CDMA system which employs Z-Complementary Se- quences (ZCS) as spreading code is investigated. The new system can not only eliminate multipath interference and Multiple Access Interfer... In this paper, a multicarrier DS-CDMA system which employs Z-Complementary Se- quences (ZCS) as spreading code is investigated. The new system can not only eliminate multipath interference and Multiple Access Interference (MAI), but also support flexible number of users com- pared with system using Orthogonal Complementary (OC) codes. Multicarrier DS-CDMA using OC codes can be regarded as a special case of our proposed system. Zero Correlation Zone (ZCZ) of ZCS can be flexibly adjusted to meet the requirements on the user number and maximum multipath and in- ter-user delay, in this way, more users can be supported without losing interference-free property. The effectiveness of the proposed system is validated through theoretical analysis and simulation results. 展开更多
关键词 Orthogonal Complementary (OC) codes Multicarrier DS-cdMA Z-Complemen-tary sequences (ZCS) Zero Correlation Zone (ZCZ)
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Intrusion Detection Model Using Chaotic MAP for Network Coding Enabled Mobile Small Cells
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作者 Chanumolu Kiran Kumar Nandhakumar Ramachandran 《Computers, Materials & Continua》 SCIE EI 2024年第3期3151-3176,共26页
Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),a... Wireless Network security management is difficult because of the ever-increasing number of wireless network malfunctions,vulnerabilities,and assaults.Complex security systems,such as Intrusion Detection Systems(IDS),are essential due to the limitations of simpler security measures,such as cryptography and firewalls.Due to their compact nature and low energy reserves,wireless networks present a significant challenge for security procedures.The features of small cells can cause threats to the network.Network Coding(NC)enabled small cells are vulnerable to various types of attacks.Avoiding attacks and performing secure“peer”to“peer”data transmission is a challenging task in small cells.Due to the low power and memory requirements of the proposed model,it is well suited to use with constrained small cells.An attacker cannot change the contents of data and generate a new Hashed Homomorphic Message Authentication Code(HHMAC)hash between transmissions since the HMAC function is generated using the shared secret.In this research,a chaotic sequence mapping based low overhead 1D Improved Logistic Map is used to secure“peer”to“peer”data transmission model using lightweight H-MAC(1D-LM-P2P-LHHMAC)is proposed with accurate intrusion detection.The proposed model is evaluated with the traditional models by considering various evaluation metrics like Vector Set Generation Accuracy Levels,Key Pair Generation Time Levels,Chaotic Map Accuracy Levels,Intrusion Detection Accuracy Levels,and the results represent that the proposed model performance in chaotic map accuracy level is 98%and intrusion detection is 98.2%.The proposed model is compared with the traditional models and the results represent that the proposed model secure data transmission levels are high. 展开更多
关键词 Network coding small cells data transmission intrusion detection model hashed message authentication code chaotic sequence mapping secure transmission
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On the Angular Distribution of the Representative Points of Bases of Human Protein Coding Sequences
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作者 Zhou Guoxiang Wang Aikun He Wenchen(Mathematics and Physics Department,Hebei University of Technology, 300130, Tianjin, China) 《河北工业大学学报》 CAS 1997年第A01期1-4,共4页
A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture i... A novel diagrammtic method is proposed to show the angular distribution of bases of human protein sequences. Using this method, the distribution sphere[1-4] is divided into four regions with same volume. The picture is clearer and more intuitive than that in [1] .A rule on the angular distribution of the representative points of bases of protein sequences is given. Besides, in 300 representative pointS of human protein sequence samples we find that there are three (not only one) points outside the sphere. 展开更多
关键词 ANGULAR DISTRIBUTION REPRESENTATIVE point of BASES of protein coding sequence/ DISTRIBUTION SPHERE
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BIT-CORRELATION MATCHING FUNCTION FOR IMAGE SEQUENCE CODING
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作者 Chang Yilin Li Bingbing Sun Xianpu Li Feipeng(Xidian University, Xi’an 710071) 《Journal of Electronics(China)》 1996年第2期134-139,共6页
This paper proposes a new block matching criterion called the bit-correlation matching function for image sequence coding. When using the identical fast searching algorithm, the bit-correlation matching function not o... This paper proposes a new block matching criterion called the bit-correlation matching function for image sequence coding. When using the identical fast searching algorithm, the bit-correlation matching function not only results in nearly the same accuracy in displacement estimation as the mean square error function, but also makes the algorithm low in computation complexity and easy to parallel implementation, thus reducing the coding time of image sequence efficiently. 展开更多
关键词 Image sequence coding DISPLACEMENT estimation Matching CRITERION
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USING ERROR-CORRECTING ENCODERS TO DESIGN LOCAL-RANDOM SEQUENCE GENERATORS
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作者 杨义先 《Journal of Electronics(China)》 1995年第1期9-14,共6页
This paper proved the statement that a good linear block encoder is in fact a good local-random sequence generator. Furthermore, this statement discovers the deep relationship between the error-correcting coding theor... This paper proved the statement that a good linear block encoder is in fact a good local-random sequence generator. Furthermore, this statement discovers the deep relationship between the error-correcting coding theory and the modern cryptography. 展开更多
关键词 Error-correcting coding CRYPTOGRAPHY RANDOM sequenceS
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Screen image sequence compression method utilizing adaptive block size coding and hierarchical GOP structure
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作者 武星 梅亮 +2 位作者 袭奇 张申生 陈延伟 《Journal of Central South University》 SCIE EI CAS 2010年第4期786-794,共9页
To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra... To compress screen image sequence in real-time remote and interactive applications,a novel compression method is proposed.The proposed method is named as CABHG.CABHG employs hybrid coding schemes that consist of intra-frame and inter-frame coding modes.The intra-frame coding is a rate-distortion optimized adaptive block size that can be also used for the compression of a single screen image.The inter-frame coding utilizes hierarchical group of pictures(GOP) structure to improve system performance during random accesses and fast-backward scans.Experimental results demonstrate that the proposed CABHG method has approximately 47%-48% higher compression ratio and 46%-53% lower CPU utilization than professional screen image sequence codecs such as TechSmith Ensharpen codec and Sorenson 3 codec.Compared with general video codecs such as H.264 codec,XviD MPEG-4 codec and Apple's Animation codec,CABHG also shows 87%-88% higher compression ratio and 64%-81% lower CPU utilization than these general video codecs. 展开更多
关键词 screen image sequence compression adaptive block size hierarchical GOP structure intra-frame coding inter-frame coding
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基于CDS..join特征域的Exon/Intron数据库的构建 被引量:2
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作者 金鹰 邓小元 《华南师范大学学报(自然科学版)》 CAS 北大核心 2009年第1期91-94,共4页
基因进化的研究和重构通常是在序列水平上进行的,包括比对它们的基因序列或蛋白序列.而对基因外显子/内含子结构的分析能够提供更多有价值的信息,比如绘制更为可靠的系统发生图谱,或更精确地阐明内含子的进化.为此,本文设计了相应的Per... 基因进化的研究和重构通常是在序列水平上进行的,包括比对它们的基因序列或蛋白序列.而对基因外显子/内含子结构的分析能够提供更多有价值的信息,比如绘制更为可靠的系统发生图谱,或更精确地阐明内含子的进化.为此,本文设计了相应的Perl脚本程序来提取、比较和搜索基因说明文档中CDS..join特征域的Exon/Intron结构.通过该方法,可构建相关物种的Exon/Intron数据库(EID),其主要内容包括内含子的相位,Exon或Intron的数量和大小,剪接位点的模式以及选择性剪接(Alternative splicing,AS)的相关信息. 展开更多
关键词 编码序列 外显子 内含子 外显子/内含子数据库 选择性剪接
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DESIGN AND PERFORMANCE OF SYMBOL/SEQUENCE TCM FOR DS/SSMA SYSTEM OVER MOBILE RADIO CHANNEL
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作者 仰枫帆 毕光国 许宗泽 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期26-32,共7页
A novel kind of multidimension symbol/sequence trellis coded modulation (TCM) based on TCM of lower coding rate has been constructed. The redundancy of this new kind of TCM is provided not only by the modulated symbo... A novel kind of multidimension symbol/sequence trellis coded modulation (TCM) based on TCM of lower coding rate has been constructed. The redundancy of this new kind of TCM is provided not only by the modulated symbol sequence but also by the PN sequences for spreading spectrum as well. The performance of direct sequence spread spectrum multiple access (DS/SSMA) system with this symbol/sequence TCM over flat Rayleigh fading channel has been investigated by theoretical analysis and numerical simulation. The results obtained in this research demonstrate the performance improvements of this system in comparison with that of the DS/SSMA system with conventional TCM under the same conditions. 展开更多
关键词 TRELLIS coded modulation direct sequence spread spectrun multiple access RAYLEIGH fading channel MAXIMAL LIKELIHOOD decaling probability of bit error rate
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GenBank中CDS..join特征域研究初步 被引量:2
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作者 金鹰 《华南师范大学学报(自然科学版)》 CAS 2008年第2期95-99,共5页
由NCBI建立和维护的大型公用数据库GenBank是进行生物学研究最为重要的工具之一.其DNA序列数据库的每条记录描述了相关基因的详细特征,其中的CDS(Coding Sequence)特征域被认为是DNA生成蛋白质的翻译指令,它对GenBank中每条基因的组装... 由NCBI建立和维护的大型公用数据库GenBank是进行生物学研究最为重要的工具之一.其DNA序列数据库的每条记录描述了相关基因的详细特征,其中的CDS(Coding Sequence)特征域被认为是DNA生成蛋白质的翻译指令,它对GenBank中每条基因的组装进行了详细的说明.通过CDS可以很容易在互联网上进行多序列搜索,并获得相关的基因序列、编码蛋白序列及种属特异性信息.利用CDS特征域构建外显子-内含子数据库(Exon-Intron Database,EID)是研究内含子起源、进化和功能的重要手段,本文试图以CDS为线索,解决建库初期从GenBank海量数据中提取相关序列的问题. 展开更多
关键词 GENBANK 编码序列 外显子 内含子 EID
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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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原核生物基因组的CDS与ORF序列的几点分析
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作者 沈世镒 高建召 +1 位作者 胡刚 王奎 《生物数学学报》 CSCD 北大核心 2009年第1期33-39,共7页
基因组的开放阅读框(ORF)是基因识别与基因组分析的基础,有多种软件包给出了它们的生成算法,但结果与指标并不统一.本文给出了po-MORF的定义与它的生成算法,证明了由基因组所确定的po-MORF集合的存在与唯一性,并由该生成算法可以得到全... 基因组的开放阅读框(ORF)是基因识别与基因组分析的基础,有多种软件包给出了它们的生成算法,但结果与指标并不统一.本文给出了po-MORF的定义与它的生成算法,证明了由基因组所确定的po-MORF集合的存在与唯一性,并由该生成算法可以得到全部po-MORF序列.我们还比较了若干原核生物基因组中所有CDS与po-MORF序列的相互关系,并讨论了关于基因识别中的有关问题. 展开更多
关键词 基因组的p_0-MORF序列 MORF生成算法 cds与ORF序列集合的相互关系
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多用户MCDS-CDMA系统中的时频域信道估计方法 被引量:3
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作者 居美艳 冉明 《电子与信息学报》 EI CSCD 北大核心 2008年第10期2537-2540,共4页
该文提出了一种用于多用户MC DS-CDMA系统的信道估计方法,该方法在平均时域估计的基础上迭代一次平均频域信道估计,较好地改善了信道估计的性能。仿真结果表明,经过平均时域信道估计方法能较大程度地滤除多址干扰(MAI)和噪声,提高信道... 该文提出了一种用于多用户MC DS-CDMA系统的信道估计方法,该方法在平均时域估计的基础上迭代一次平均频域信道估计,较好地改善了信道估计的性能。仿真结果表明,经过平均时域信道估计方法能较大程度地滤除多址干扰(MAI)和噪声,提高信道估计的准确性。再经过迭代一次平均频域信道估计,系统的误码率(BER)性能还可进一步改善,经过两次信道估计,系统取得的性能已很接近理想估计的性能。 展开更多
关键词 MC DS—cdMA 信道估计 时域信道估计 频域信道估计
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