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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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Pseudo DNA Sequence Generation of Non-Coding Distributions Using Variant Maps on Cellular Automata
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作者 Jeffrey Zheng Jin Luo Wei Zhou 《Applied Mathematics》 2014年第1期153-174,共22页
In a recent decade, many DNA sequencing projects are developed on cells, plants and animals over the world into huge DNA databases. Researchers notice that mammalian genomes encoding thousands of large noncoding RNAs ... In a recent decade, many DNA sequencing projects are developed on cells, plants and animals over the world into huge DNA databases. Researchers notice that mammalian genomes encoding thousands of large noncoding RNAs (lncRNAs), interact with chromatin regulatory complexes, and are thought to play a role in localizing these complexes to target loci across the genome. It is a challenge target using higher dimensional tools to organize various complex interactive properties as visual maps. In this paper, a Pseudo DNA Variant MapPDVM is proposed following Cellular Automata to represent multiple maps that use four Meta symbols as well as DNA or RNA representations. The system architecture of key components and the core mechanism on the PDVM are described. Key modules, equations and their I/O parameters are discussed. Applying the PDVM, two sets of real DNA sequences from both the sample human (noncoding DNA) and corn (coding DNA) genomes are collected in comparison with two sets of pseudo DNA sequences generated by a stream cipher HC-256 under different modes to show their intrinsic properties in higher levels of similar relationships among relevant DNA sequences on 2D maps. Sample 2D maps are listed and their characteristics are illustrated under a controllable environment. Various distributions can be observed on both noncoding and coding conditions from their symmetric properties on 2D maps. 展开更多
关键词 Large Noncoding dna Analysis Stream CIPHER HC-256 Binary to dna PSEUDO dna sequence Visual Distribution VARIANT Map
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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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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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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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DNA存储场景下的大小喷泉码模型设计
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作者 崔竞松 蒋昌跃 郭迟 《计算机工程与科学》 CSCD 北大核心 2024年第1期72-82,共11页
在DNA存储等应用场景中,传统喷泉码算法需要占用额外信道资源将源文件分组数目K传递给解码端。在实际应用中,虽然可以将K嵌入在每一个编码数据分组中进行传递,但这种做法会严重浪费信道的带宽。针对上述问题,提出了一种大小喷泉码模型,... 在DNA存储等应用场景中,传统喷泉码算法需要占用额外信道资源将源文件分组数目K传递给解码端。在实际应用中,虽然可以将K嵌入在每一个编码数据分组中进行传递,但这种做法会严重浪费信道的带宽。针对上述问题,提出了一种大小喷泉码模型,通过增加小喷泉码这一带外信道来优化关键参数的传递。小喷泉码将每个编码分组中有关参数K所占用空间的粒度降至1 bit,有效减少了带宽资源的消耗。此外,小喷泉码还能适应由于DNA存储介质不均匀所导致的编码序列不定长的限制条件,一定条件下甚至可以完全不占用额外信道带宽。 展开更多
关键词 dna存储 喷泉码 LT码 规避序列
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新型超声快速处理活检标本保存不同年限对DNA质量的影响
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作者 石晨曦 朱卫东 +3 位作者 李三恩 李秀明 师逢 丁亚云 《中国组织工程研究》 CAS 北大核心 2025年第13期2655-2660,共6页
背景:新型超声组织处理技术越来越多地被用来进行分子生物学分析,研究新型超声处理不同存储年限组织DNA的质量,对进一步分子检测的标本质控具有重要意义。目的:探讨新型超声处理活检标本存储不同年限对DNA质量的影响,以期为分子检测探... 背景:新型超声组织处理技术越来越多地被用来进行分子生物学分析,研究新型超声处理不同存储年限组织DNA的质量,对进一步分子检测的标本质控具有重要意义。目的:探讨新型超声处理活检标本存储不同年限对DNA质量的影响,以期为分子检测探索最佳的标本存储时间。方法:收集40例乳腺穿刺小活检组织,采用超声技术制作石蜡标本,按照存储年限分为4组:<1年组、1-3年组、>3-5年组及>5年组,每组10例,对石蜡标本进行切片,每张切片厚3μm,切片10-15张,提取DNA后通过Nanophotometer N60超微量分光光度计和Qubit 4.0荧光计检测DNA的质量浓度,记录A_(260)/A_(280)比值判定DNA的纯度,利用全自动毛细管电泳核酸分析仪(Qsep 100)检测DNA片段完整性,以评估DNA片段的质量。结果与结论:4组样本A_(260)/A_(280)均值在1.8-2.0之间,达到纯度要求,无明显差异。4组样本的DNA质量浓度(Qubit浓度)均值分别为30.39,14.33,2.52,1.95 ng/μL;DNA的平均N/Q比值分别为6.48,14.18,24.56,29.86;DNA质量数均值分别为5.64,1.76,1.24,0.80;大片段占比均值分别为56.08%,17.72%,12.68%,7.90%。PCR检测内控基因Ct均值分别为15.32,17.09,18.39,21.24。与<1年组相比,其余3组DNA浓度显著降低,N/Q比值显著增加,DNA质量数和大片段占比均值显著降低,Ct值升高,差异有显著性意义(P<0.05)。实验结果表明,对于新型超声处理活检标本,应优先选择存储<1年的样本进行日常分子检测,储存3年内的样本可满足二代测序等检测要求,5年内样本仅可尝试进行PCR等检测,存储超过5年的样本不建议进行后续分子检测。 展开更多
关键词 超声处理 存储年限 dna质量 片段完整性 降解程度 二代测序
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循环肿瘤DNA在膀胱癌中的研究进展及临床价值
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作者 张勇 李伟宏 王毓斌 《现代泌尿外科杂志》 CAS 2024年第6期555-559,共5页
随着生物技术的发展,液体活检技术在肿瘤方面的研究逐渐深入,循环肿瘤DNA(ctDNA)作为液体活检的主要方式之一,以其非侵入性、可重复性及可早期发现病变等特点备受关注。目前有研究表明ctDNA在膀胱癌(BCa)的早期诊断和分级、靶向治疗的... 随着生物技术的发展,液体活检技术在肿瘤方面的研究逐渐深入,循环肿瘤DNA(ctDNA)作为液体活检的主要方式之一,以其非侵入性、可重复性及可早期发现病变等特点备受关注。目前有研究表明ctDNA在膀胱癌(BCa)的早期诊断和分级、靶向治疗的选择和疗效分析、肿瘤的复发及进展等方面有一定的潜能,本文结合ctDNA的特点及其近年来在BCa中的研究进展和临床价值进行综述。ctDNA检测技术近年不断发展,人们在测序、突变测定技术发展及在增强其作为癌症检测生物标志物能力方面做出多项进展与尝试。对血浆样本中ctDNA的检测有助于在早期BCa的诊断中实现准确分类,但由于ctDNA含量低,需要更先进检测技术的支持;基于靶向测序的ctDNA分析是预测非肌层浸润性膀胱癌(NMIBC)患者疾病复发和侵袭性的一种有希望的方法。在晚期BCa患者中,可以应用ctDNA收集特有突变类型的特点,有针对性地指导用药、调整治疗及监测预后。尽管ctDNA在BCa的应用仍存在挑战,但已表现出广泛的应用前景。 展开更多
关键词 液体活检 循环肿瘤dna 膀胱癌 测序 靶向 突变 辅助治疗 靶向治疗
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DNA测序首段信号数据特别处理方法研究
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作者 贾二惠 张欣欣 +1 位作者 管桦 李明 《分析仪器》 CAS 2024年第4期59-63,共5页
针对荧光标记毛细管电泳DNA测序开始一段序列的信号杂乱特性以及不同碱基通道信号间的相对偏移问题,提出了一种用于首段信号特别处理的电泳迁移率自适应校正方法。分析设计基于四通道首段信号间峰重叠程度估计的运筹决策目标函数,通过... 针对荧光标记毛细管电泳DNA测序开始一段序列的信号杂乱特性以及不同碱基通道信号间的相对偏移问题,提出了一种用于首段信号特别处理的电泳迁移率自适应校正方法。分析设计基于四通道首段信号间峰重叠程度估计的运筹决策目标函数,通过目标函数动态寻优计算确定不同碱基通道信号的相对偏移系数,从而实现DNA测序首段信号的相对偏移校正,为提高首段信号碱基的合理判读及后续DNA精准排序提供了可靠的过程数据。 展开更多
关键词 dna测序 毛细管电泳 首段信号 数据处理 目标函数 动态寻优
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Molecular hallmarks of long non-coding RNAs in aging and its significant effect on aging-associated diseases 被引量:6
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作者 Syed Aoun Mehmood Sherazi Asim Abbasi +9 位作者 Abdullah Jamil Mohammad Uzair Ayesha Ikram Shanzay Qamar Adediji Ayomide Olamide Muhammad Arshad Peter J.Fried Milos Ljubisavljevic Ran Wang Shahid Bashir 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期959-968,共10页
Aging is linked to the deterioration of many physical and cognitive abilities and is the leading risk factor for Alzheimer’s disease. The growing aging population is a significant healthcare problem globally that res... Aging is linked to the deterioration of many physical and cognitive abilities and is the leading risk factor for Alzheimer’s disease. The growing aging population is a significant healthcare problem globally that researchers must investigate to better understand the underlying aging processes. Advances in microarrays and sequencing techniques have resulted in deeper analyses of diverse essential genomes(e.g., mouse, human, and rat) and their corresponding cell types, their organ-specific transcriptomes, and the tissue involved in aging. Traditional gene controllers such as DNA-and RNA-binding proteins significantly influence such programs, causing the need to sort out long non-coding RNAs, a new class of powerful gene regulatory elements. However, their functional significance in the aging process and senescence has yet to be investigated and identified. Several recent researchers have associated the initiation and development of senescence and aging in mammals with several well-reported and novel long non-coding RNAs. In this review article, we identified and analyzed the evolving functions of long non-coding RNAs in cellular processes, including cellular senescence, aging, and age-related pathogenesis, which are the major hallmarks of long non-coding RNAs in aging. 展开更多
关键词 AGING Alzheimer’s disease dna sequence EPIGENETICS immune non-coding RNA OLIGONUCLEOTIDES telomere-associated
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水生生物环境DNA监测技术的发展、应用与标准化 被引量:2
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作者 谷思雨 陈凯 +13 位作者 金小伟 李文攀 陈晓飞 熊晶 汤敏喆 姜传奇 熊杰 李涛 张琪 崔永德 曾宏辉 何舜平 王业耀 缪炜 《水生生物学报》 CAS CSCD 北大核心 2024年第8期1443-1458,共16页
水生态系统是保障国家生态安全的重要基础。水生生物在水生态系统中扮演着核心角色,是研究水体演变的重要依据,是维护水生态健康的关键。传统水生生物调查和监测通常采用形态学方法,但其存在专业知识要求高、难以标准化和自动化及费时... 水生态系统是保障国家生态安全的重要基础。水生生物在水生态系统中扮演着核心角色,是研究水体演变的重要依据,是维护水生态健康的关键。传统水生生物调查和监测通常采用形态学方法,但其存在专业知识要求高、难以标准化和自动化及费时耗力等缺陷。环境DNA(Environmental DNA,简称eDNA)技术是一种通过监测环境中存在的DNA片段来识别特定生物物种的方法,可以实现基于水体中DNA分子进行水生生物的鉴定和监测,为水生生物的常态化监测提供了一个准确、便捷、可标准化和自动化实施的方案。文章介绍了eDNA技术的基本原理,总结回顾了eDNA技术从萌芽到广泛科研应用的发展历史和过程,介绍了基于eDNA的宏条形码和宏基因组等各类水生生物鉴定监测技术;阐述了eDNA技术在保护种、入侵种及生物类群监测和水生态评估等各领域的应用;分析了eDNA技术当前面临的物种参考序列数据库不完善等各类挑战;提出了通过优化完善数据库、样品采集方法、评价指标和参数、样品保藏、数据分析和存储等来推动eDNA技术标准化和自动化,以解决当前面临的挑战。同时,基于eDNA技术当前的发展阶段,提出了在我国水体结合专业形态分类鉴定开展水生生物eDNA技术标准化监测的实施建议。 展开更多
关键词 环境dna技术 标准化 水生生物监测 宏条形码测序技术 宏基因组测序技术 edna数据库
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DNA存储技术:挑战与未来 被引量:1
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作者 褚利康 何磊 韩达 《集成技术》 2024年第3期116-127,共12页
随着全球数据呈现指数级增长,当前的信息存储技术面临维护成本高昂、存储寿命有限等多个缺陷,逐渐无法满足日益凸显的需求。因此,迫切需要引入新的信息存储方法来解决这一问题。DNA作为一种天然的遗传信息载体,具备高存储密度、潜在低... 随着全球数据呈现指数级增长,当前的信息存储技术面临维护成本高昂、存储寿命有限等多个缺陷,逐渐无法满足日益凸显的需求。因此,迫切需要引入新的信息存储方法来解决这一问题。DNA作为一种天然的遗传信息载体,具备高存储密度、潜在低维护成本和长寿命等优势,因此被视为一种有潜力的新型信息存储介质。该文对DNA数据存储技术的基本原理和流程进行了概述,并回顾了其历史发展。同时,对当前基于DNA存储的领域仍面临的挑战进行了总结,如缓慢的数据写入和读取速度等,以及应对这些挑战的一些潜在策略。最后,为了满足全球对新存储方法的需求,该文指出了DNA数据存储技术的未来发展方向。 展开更多
关键词 dna 数据存储 dna序列 dna纳米技术 信息加密
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Pse-in-One 2.0: An Improved Package of Web Servers for Generating Various Modes of Pseudo Components of DNA, RNA, and Protein Sequences 被引量:12
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作者 Bin Liu Hao Wu Kuo-Chen Chou 《Natural Science》 2017年第4期67-91,共25页
Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and compr... Pse-in-One 2.0 is a package of web-servers evolved from Pse-in-One (Liu, B., Liu, F., Wang, X., Chen, J. Fang, L. & Chou, K.C. Nucleic Acids Research, 2015, 43:W65-W71). In order to make it more flexible and comprehensive as suggested by many users, the updated package has incorporated 23 new pseudo component modes as well as a series of new feature analysis approaches. It is available at http://bioinformatics.hitsz.edu.cn/Pse-in-One2.0/. Moreover, to maximize the convenience of users, provided is also the stand-alone version called “Pse-in-One-Analysis”, by which users can significantly speed up the analysis of massive sequences. 展开更多
关键词 PSEUDO COMPONENTS dna sequences RNA sequences Protein sequences
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DNA甲基化修饰对金钱鱼卵巢Cyp17a1表达水平的影响 被引量:1
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作者 周一帆 江政霆 +5 位作者 李雨 焦开智 潘书慧 许芮 李广丽 江东能 《广东海洋大学学报》 CAS CSCD 北大核心 2024年第2期46-53,共8页
【目的】分析DNA甲基化修饰对金钱鱼(Scatophagus argus)卵巢Cyp17a1表达的影响,进一步认识卵巢发育成熟相关基因表达的调控机制。【方法】分别取卵巢发育III、IV期的金钱鱼,以及投喂添加0(对照)、50、100μg/g雌二醇饲料30 d的2龄雌鱼,... 【目的】分析DNA甲基化修饰对金钱鱼(Scatophagus argus)卵巢Cyp17a1表达的影响,进一步认识卵巢发育成熟相关基因表达的调控机制。【方法】分别取卵巢发育III、IV期的金钱鱼,以及投喂添加0(对照)、50、100μg/g雌二醇饲料30 d的2龄雌鱼,用MethPrimer软件分析其Cyp17a1基因CpG二核苷酸位点分布特征,并预测CpG岛;采用亚硫酸氢盐测序法检测不同发育时期卵巢以及投喂雌二醇个体卵巢中的Cyp17a1的DNA甲基化修饰水平,并用实时荧光定量PCR分析Cyp17a1基因表达水平。【结果】金钱鱼Cyp17a1翻译起始位点2000 bp后无CpG岛,取第1外显子含有5个CpG位点(翻译起始位点后106、116、129、148和203 bp处)的区域用于DNA甲基化水平检测。金钱鱼III期卵巢Cyp17a1外显子1的DNA甲基化修饰水平显著高于IV期卵巢(P<0.05),与其mRNA表达水平呈负相关。116、129和203 bp处DNA甲基化存在发育时期差异,但106和148 bp处差异不显著(P>0.05)。投喂雌二醇后,金钱鱼卵巢Cyp17a1 mRNA表达水平和第1外显子CpG富集区域整体DNA甲基化修饰水平无显著变化(P>0.05),但雌激素处理雌鱼翻译起始位点后148、203 bp处甲基化水平明显上升(P<0.05)。【结论】金钱鱼卵巢Cyp17a1第一个外显子CpG富集区的整体甲基化水平与基因表达呈负相关,饲料E2可上调Cyp17a1第一个外显子148、205 bp处甲基化水平,表明甲基化修饰参与金钱鱼Cyp17a1的表达调控。 展开更多
关键词 金钱鱼 Cyp17a1 基因表达 亚硫酸氢盐测序法 dna甲基化
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Molecular Taxonomy of Conogethes punctiferalis and Conogethes pinicolalis(Lepidoptera: Crambidae) Based on Mitochondrial DNA Sequences 被引量:6
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作者 WANG Jing ZHANG Tian-tao +3 位作者 WANG Zhen-ying HE Kang-lai LIU Yong LI Jing 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2014年第9期1982-1989,共8页
Conogethes punctiferalis(Guenée)(Lepidoptera: Crambidae) was originally considered as one species with fruit-feeding type(FFT) and pinaceae-feeding type(PFT), but it has subsequently been divided into tw... Conogethes punctiferalis(Guenée)(Lepidoptera: Crambidae) was originally considered as one species with fruit-feeding type(FFT) and pinaceae-feeding type(PFT), but it has subsequently been divided into two different species of Conogethes punctiferalis and Conogethes pinicolalis. The relationship between the two species was investigated by phylogenetic reconstruction using maximum-likelihood(ML) parameter estimations. The phylogenetic tree and network were constructed based upon sequence data from concatenation of three genes of mitochondrial cytochrome c oxidase subunits I, II and cytochrome b which were derived from 118 samples of C. punctiferalis and 24 samples of C. pinicolalis. The phylogenetic tree and network showed that conspecific sequences were clustering together despite intraspecific variability. Here we report the results of a combined analysis of mitochondrial DNA sequences from three genes and morphological data representing powerful evidence that C. pinicolalisand C. punctiferalis are significantly different. 展开更多
关键词 yellow peach moth Conogethes punctiferalis Conogethes pinicolalis mitochondrial dna sequence
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Sequences Characterization of Microsatellite DNA Sequences in Pacific Abalone(Haliotis discus hannai) 被引量:3
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作者 Kijima Akihiro 《Journal of Ocean University of China》 SCIE CAS 2007年第1期47-52,共6页
The microsatellite-enriched library was constructed using magnetic bead hybridization selection method, and the mi-crosatellite DNA sequences were analyzed in Pacific abalone Haliotis discus hannai. Three hundred and ... The microsatellite-enriched library was constructed using magnetic bead hybridization selection method, and the mi-crosatellite DNA sequences were analyzed in Pacific abalone Haliotis discus hannai. Three hundred and fifty white colonies were screened using PCR-based technique, and 84 clones were identified to potentially contain microsatellite repeat motif. The 84 clones were sequenced, and 42 microsatellites and 4 minisatellites with a minimum of five repeats were found (13.1% of white colonies screened). Besides the motif of CA contained in the oligoprobe, we also found other 16 types of microsatellite repeats including a dinucleotide repeat, two tetranucleotide repeats, twelve pentanucleotide repeats and a hexanucleotide repeat. According to Weber (1990), the microsatellite sequences obtained could be categorized structurally into perfect repeats (73.3%), imperfect repeats (13.3%), and compound repeats (13.4%). Among the microsatellite repeats, relatively short arrays (< 20 repeats) were most abundant, accounting for 75.0%. The largest length of microsatellites was 48 repeats, and the average number of repeats was 13.4. The data on the composition and length distribution of microsatellites obtained in the present study can be useful for choosing the repeat motifs for microsatellite isolation in other abalone species. 展开更多
关键词 HALIOTIS DISCUS HANNAI MICROSATELLITE dna sequence CHARACTERIZATION
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Chaos game representation(CGR)-walk model for DNA sequences 被引量:4
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作者 高洁 徐振源 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第1期370-376,共7页
Chaos game representation (CGR) is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their ... Chaos game representation (CGR) is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their positions in a continuous space. This distribution of positions has two features: one is unique, and the other is source sequence that can be recovered from the coordinates so that the distance between positions may serve as a measure of similarity between the corresponding sequences. A CGR-walk model is proposed based on CGR coordinates for the DNA sequences. The CGR coordinates are converted into a time series, and a long-memory ARFIMA (p, d, q) model, where ARFIMA stands for autoregressive fractionally integrated moving average, is introduced into the DNA sequence analysis. This model is applied to simulating real CGR-walk sequence data of ten genomic sequences. Remarkably long-range correlations are uncovered in the data, and the results from these models are reasonably fitted with those from the ARFIMA (p, d, q) model. 展开更多
关键词 CGR-walk model dna sequence LONG-MEMORY ARFIMA(p d q) model
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Phylogeny of Ptychostomum (Bryaceae,Musci) inferred from sequences of nuclear ribosomal DNA internal transcribed spacer (ITS) and chloroplast rps4 被引量:2
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作者 Chen-Ying WANG Jian-Cheng ZHAO 《Journal of Systematics and Evolution》 SCIE CSCD 北大核心 2009年第4期311-320,共10页
The phylogeny of Ptychostomum was first spacer (ITS) region of the nuclear ribosomal (nr) DNA DNA rps4 sequences. Maximum parsimony, maximum undertaken based on analysis of the internal transcribed and by combinin... The phylogeny of Ptychostomum was first spacer (ITS) region of the nuclear ribosomal (nr) DNA DNA rps4 sequences. Maximum parsimony, maximum undertaken based on analysis of the internal transcribed and by combining data from nrDNA ITS and chloroplast likelihood, and Bayesian analyses all support the conclusion that the reinstated genus Ptychostomum is not monophyletic. Ptychostomum funkii (Schwagr.) J. R. Spence (≡ Bryum funkii Schwaigr.) is placed within a clade containing the type species of Bryum, B. argenteum Hedw. The remaining members of Ptychostomum investigated in the present study constitute another well-supported clade. The results are congruent with previous molecular analyses. On the basis of phylogenetic evidence, we agree with transferring B. amblyodon Mull. Hal. (≡ B. inclinatum (Brid.) Turton≡ Bryum archangelicum Bruch & Schimp.), Bryum lonchocaulon Mull. Hal., Bryum pallescens Schleich. ex Schwaigr., and Bryum pallens Sw. to Ptychostomum. 展开更多
关键词 Bryum molecular phylogeny nuclear ribosomal dna internal transcribed spacer sequences Ptychostomum rps4 sequences.
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重叠延伸PCR生成长重复DNA序列及其在纳米孔测序中的应用
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作者 宋子婷 程冰晓 +2 位作者 胡坤灵 安然 梁兴国 《中国海洋大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第9期157-164,共8页
短链DNA的纳米孔测序存在孔道利用率低、数据质量差等问题。因此,亟需建立一种用纳米孔测序技术准确测定短链DNA序列的方法。本研究以1 nmol/L完全互补的序列为引物,以短链DNA为模板,在72℃退火温度下进行PCR,实现了短链DNA的重叠延伸,... 短链DNA的纳米孔测序存在孔道利用率低、数据质量差等问题。因此,亟需建立一种用纳米孔测序技术准确测定短链DNA序列的方法。本研究以1 nmol/L完全互补的序列为引物,以短链DNA为模板,在72℃退火温度下进行PCR,实现了短链DNA的重叠延伸,最终生成长串联重复序列,其产物长度为原始长度的5~20倍。生成的长链DNA可直接测序,仅需对齐单个或少数几个Reads进行简单分析即可获得精确的序列信息。本研究所开发的重叠延伸法将纳米孔One read精确度提高至99.28%,这对提高纳米孔测序的精度具有重要作用。 展开更多
关键词 短链dna 重复序列 纳米孔测序 重叠延伸 高精度
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不同单细胞全基因组扩增体系扩增牛微量血液DNA效果评价
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作者 牛一凡 李崇阳 +7 位作者 杨柏高 张培培 张航 冯肖艺 曹建华 余洲 马友记 赵学明 《畜牧兽医学报》 CAS CSCD 北大核心 2024年第8期3436-3445,共10页
旨在通过二代测序技术评估不同单细胞全基因组扩增(single cell whole genome amplification,scWGA)体系对牛微量血液基因组DNA的扩增效果,建立微量DNA全基因组扩增体系。本研究分别采用MDA(multiple displacement amplification)和MALB... 旨在通过二代测序技术评估不同单细胞全基因组扩增(single cell whole genome amplification,scWGA)体系对牛微量血液基因组DNA的扩增效果,建立微量DNA全基因组扩增体系。本研究分别采用MDA(multiple displacement amplification)和MALBAC(multiple annealing and looping-based amplification cycles)两种scWGA体系对华西牛1 ng血液基因组DNA进行全基因组扩增,随后基于两种体系的扩增产物以及原始未稀释血液DNA构建测序文库,利用DNBSEQ-T7RS测序平台进行全基因组测序(whole genome sequencing,WGS),通过比较扩增产物片段大小、浓度、总质量评估扩增效率,通过分析GC含量、测序覆盖度、基因分型一致率、基因型检出率等评估两种体系的扩增效果。结果显示,MDA体系的扩增产物片段大于MALBAC体系(8 kb vs.0.2~2 kb),产物浓度和总质量显著高于MALBAC体系(P<0.05)。基于测序数据,1×和5×测序深度下,MDA体系的基因组覆盖度显著高于MALBAC体系(P<0.05),此外,MDA体系的分型一致率、检出率显著高于MALBAC体系,而等位基因缺失率、假阳性率显著低于MALBAC体系(P<0.05)。综上,本研究揭示了MDA和MALBAC两种扩增体系基于华西牛1 ng血液基因组DNA扩增的体系特点,为改进现有华西牛胚胎基因组选择中的关键扩增技术提供理论依据,促进华西牛遗传育种进展。 展开更多
关键词 全基因组扩增 MDA MALBAC 微量dna扩增体系
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