Next-generation sequencing technologies for environmental DNA research

Since 2005, advances in next-generation sequencing technologies have revolutionized biological science. The analysis of environmental DNA through the use of specific gene markers such as species-specific DNA barcodes has been a key application of next-generation sequencing technologies in ecological and environmental research. Access to parallel, massive amounts of sequencing data, as well as subsequent improvements in read length and throughput of different sequencing platforms, is leading to a better representation of sample diversity at a reasonable cost. New technologies are being developed rapidly and have the potential to dramatically accelerate ecological and environmental research. The fast pace of development and improvements in next-generation sequencing technologies can reflect on broader and more robust applications in environmental DNA research. Here, we review the advantages and limitations of current next-generation sequencing technologies in regard to their application for environmental DNA analysis.     

Single-molecule DNA sequencing technologies for future genomics research

During the current genomics revolution, the genomes of a large number of living organisms have been fully sequenced. However, with the advent of new sequencing technologies, genomics research is now at the threshold of a second revolution. Several second-generation sequencing platforms became available in 2007, but a further revolution in DNA resequencing technologies is being witnessed in 2008, with the launch of the first single-molecule DNA sequencer (Helicos Biosciences), which has already been used to resequence the genome of the M13 virus. This review discusses several single-molecule sequencing technologies that are expected to become available during the next few years and explains how they might impact on genomics research.     

高通量测序技术及其在微生物学研究中的应用

20世纪70年代发明的核酸测序技术为基因组学及其相关学科的发展做出了巨大贡献,本世纪初发展的以Illumina公司的HiSeq 2000,ABI公司的SOLID,和Roche公司的454技术为代表的高通量测序技术又为基因组学的发展注入了新活力.本文在阐述这些技术的基础上,着重讨论了新一代测序技术在微生物领域中的应用.     

分析植物应答环境因子的一种有效平台--DNA微阵列

随着植物基因组测序工程的迅速发展,大量的DNA序列不断地快速对外公布。如何把这庞大的核苷酸序列信息与植物的生命活动有机地联系起来?高通量的DNA微阵列技术是连接植物基因组序列信息和植物功能基因组的桥梁;而且,这一技术在分析基因表达谱和基因的功能上已经得到了应用。通过简要叙述DNA微阵列技术的几个特点,着重分析近几年来该技术在研究植物对环境胁迫的响应机制以及环境信号间相互作用方面的应用。     

乳酸菌基因芯片应用研究进展

基因芯片技术是上世纪90年代兴起的一种对成百上千甚至上万个基因同时进行检测的新技术,具有高通量、并行化的特点,广泛应用于基因表达谱测定、基因功能预测、基因突变检测和多态性分析等方面。多种乳酸菌基因组全序列以及其大量EST、16S rDNA、16S-23S基因间区和功能基因序列测定的完成,有力地推动了基因芯片技术在乳酸菌研究中的应用。介绍了基因芯片的基本原理及乳酸菌基因芯片在基因表达、种属鉴定等研究中的应用进展,以期更好地利用和开发乳酸菌基因芯片。     

非损伤性取样样品中富集宿主DNA的研究进展

非损伤性取样被广泛应用在动物保护遗传学、分子生态学和分子进化等研究领域。随着基因组测序技术的发展和基因组学时代的到来,如何从非损伤性取样样品中获取能够用于进行基因组测序的高质量DNA是研究者面临的难题。本文总结和比较了非损伤性取样中最常用的粪便样品和考古材料或博物馆标本两类样品中富集宿主DNA的方法及应用,以期为非损伤性取样在动物基因组学的研究和应用提供重要参考。     

DNA芯片技术研究进展

DNA芯片技术是近年来发展迅速的生物高技术 .其基本过程是采用寡核苷酸原位合成或显微打印手段 ,将大量探针片段有序地固化于支持物如硅芯片的表面 ,然后与扩增、标记的生物样品杂交 ,通过对杂交信号的检测分析 ,即可得出样品的遗传信息 .该技术不仅可以对遗传信息进行定性、定量分析 ,而且扩展到基因组研究和基因诊断等方面的应用 .尽管目前在硬件和软件上还面临一些困难 ,但其发展和应用的前景广阔 .     

植物的功能基因组学研究进展

基因组研究计划包括以全基因组测序为目标的结构基因组学和以基因功能鉴定为目标的功能基因组学两方面的内容。目前基因功能鉴定的方法主要有：基因表达的系统分析(SAGE)、cDNA微阵列、DNA(基因)芯片、蛋白组技术以及基于转座子标签和T_DNA标签的反求遗传学技术等。本文对上述各种技术的优缺点以及它们在植物基因功能鉴定中的应用进行了综述。 Abstract: The genome projects comprise the structural genomics focusing on determining the complete sequences of the genome and the functional genomics focusing on elucidating the biological function of genes.The rapidly evolving tools for functional genomics research include Serial Analysis of Gene Expression (SAGE),cDNA microarray,DNA (or gene) chips,proteome project and the reverse genetics technique based on the well-established transposon tagging and T?DNA tagging systems.In this paper,the advantages and disadvantages of such techniques and application of these techniques in plant functional genomics research are reviewed and future prospective are also presented.     

纳米孔测序信号处理及其在DNA数据存储的应用

随着高通量测序技术的不断更新,可以在单个分子水平读取核苷酸序列的第三代测序技术迅速发展,纳米孔测序技术是其具有代表性的单分子测序技术,该技术通过检测DNA单链分子穿过纳米孔时引起的跨膜电流信号的变化,实现碱基识别。纳米孔测序仪在便携性、碱基读取速度、测序读段长度等方面较传统的第一代与第二代测序技术都有明显优势。随着纳米孔测序技术的不断发展成熟,与其配套的各种信号处理与生物信息处理工具也迅速涌现,碱基识别和模型仿真是其中两个较为关键的研究方向。首先介绍纳米孔测序基本原理与信号处理流程,探讨其目前面临的挑战,归纳近年来在碱基识别与纳米孔模型仿真两个方面的主要进展与发展趋势,并用实测数据比较了不同碱基识别方法的性能。继而搭建了纳米孔测序集成仿真平台,为信号处理算法的评估提供支撑。进一步,随着全球数据量的爆发式增长,DNA数据存储正成为未来非常有潜力的海量数据存储方式,采用纳米孔测序读出是一种非常有效的方法。总结了纳米孔测序技术在DNA数据存储中的应用进展,分析了其可行性。分析了基于纳米孔测序实现的人工染色体数据存储的快速读出方法,探讨了与实际测序数据结合的纳米孔测序读段仿真在DNA数据存储中的应用,为开发适合DNA数据存储的方案提供参考。     

DNA microarray technology in toxicogenomics of aquatic models: methods and applications

Toxicogenomics represents the merging of toxicology with genomics and bioinformatics to investigate biological functions of genome in response to environmental contaminants. Aquatic species have traditionally been used as models in toxicology to characterize the actions of environmental stresses. Recent completion of the DNA sequencing for several fish species has spurred the development of DNA microarrays allowing investigators access to toxicogenomic approaches. However, since microarray technology is thus far limited to only a few aquatic species and derivation of biological meaning from microarray data is highly dependent on statistical arguments, the full potential of microarray in aquatic species research has yet to be realized. Herein we review some of the issues related to construction, probe design, statistical and bioinformatical data analyses, and current applications of DNA microarrays. As a model a recently developed medaka (Oryzias latipes) oligonucleotide microarray was described to highlight some of the issues related to array technology and its application in aquatic species exposed to hypoxia. Although there are known non-biological variations present in microarray data, it remains unquestionable that array technology will have a great impact on aquatic toxicology. Microarray applications in aquatic toxicogenomics will range from the discovery of diagnostic biomarkers, to establishment of stress-specific signatures and molecular pathways hallmarking the adaptation to new environmental conditions.     

单细胞基因组学分析的技术前沿

基因组学已经深刻地改变了生命科学的诸多领域的面貌。目前它的主要内容是新的全基因组碱基序列的测定和在全基因组范围内鉴定那些在不同水平上影响生命活动的基因群的功能和相互作用。为达此要求,近年出现的第二代测序(深度测序)技术和基因芯片技术发挥了关键作用,但是两者都需要足够的高质量的核酸样品。所以,在只有或只能用单细胞或极少量细胞的情况下,如果没有特殊手段,上述分析往往不能常规、方便地进行。文章以DNA扩增为主线,综合阐述了目前在单细胞(特别是微生物)全基因组测序和大基因组的靶向重测序,以及对单细胞或微量细胞进行的基于深度测序或芯片杂交的功能基因组分析,如转录组、ChIP和DNA的CpG甲基化分析等的最新策略和技术,评价了单细胞基因组测序和功能基因组学各技术的特点并对发展前景进行了展望。     

History of chloroplast genomics

The presence of chloroplast DNA was established in 1963. With the development of recombinant DNA technologies, chloroplast DNA was selected as one of the first candidates for genome sequencing. The first physical map was reported for maize chloroplasts in 1976. As tobacco has been popular as an experimental system, tobacco chloroplast DNA has been extensively analyzed and the complete nucleotide sequence was established in 1986. This sequencing and the availability of tobacco chloroplast transformation techniques and of in vitro expression systems have formed the basis of an ongoing functional genomics program. This revised version was published online in August 2006 with corrections to the Cover Date.     

合成基因组学：设计与合成的艺术

随着基因组相关技术(测序、编辑、合成等)和知识(功能基因组学)的日益成熟,合成基因组学在本世纪迎得了发展的契机。病毒、原核生物的全基因组相继被化学合成并支持生命的存活,第1个真核生物合成基因组计划已经完成过半,人类基因组编写计划提上日程。在基因组合成的实践过程中,研究者们不断探索对基因组进行重编和设计所应遵循的规则,提高从头合成、组装和替换基因组的技术手段。合成基因组在工业、环境、健康和基础研究领域有着广阔的应用前景,同时也带来了相应的伦理问题。结合在Sc2.0计划中的基因组合成研究和近期合成基因组学所取得的重大进展,本文综述了基因组设计和合成相关的科学、技术和伦理内容,并探讨了未来发展所面对的挑战。作为合成生物学最重要的领域之一,合成基因组学方兴未艾。     

Progress in the detection of human genome structural variations

The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3 Mb in the human genome. These variants include copy number variations (CNVs), inversions, insertions, deletions and other complex rearrangements of DNA sequences. This paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential influences. Particularly, we highlight the array-based, PCR-based and sequencing-based assays, including array-based comparative genomic hybridization (aCGH), representational oligonucleotide microarray analysis (ROMA), multiplex amplifiable probe hybridization (MAPH), multiplex ligation-dependent probe amplification (MLPA), paired-end mapping (PEM), and next-generation DNA sequencing technologies. Furthermore, we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable. Supported by the National High Technology Research and Development Program of China (Grant No. 2006AA020704).     

The impact of next-generation sequencing on genomics

This article reviews basic concepts,general applications,and the potential impact of next-generation sequencing(NGS)technologies on genomics,with particular reference to currently available and possible future platforms and bioinformatics.NGS technologies have demonstrated the capacity to sequence DNA at unprecedented speed,thereby enabling previously unimaginable scientific achievements and novel biological applications.But,the massive data produced by NGS also presents a significant challenge for data storage,analyses,and management solutions.Advanced bioinformatic tools are essential for the successful application of NGS technology.As evidenced throughout this review,NGS technologies will have a striking impact on genomic research and the entire biological field.With its ability to tackle the unsolved challenges unconquered by previous genomic technologies,NGS is likely to unravel the complexity of the human genome in terms of genetic variations,some of which may be confined to susceptible loci for some common human conditions.The impact of NGS technologies on genomics will be far reaching and likely change the field for years to come.     

精准高效外源DNA整合技术研究进展

精准高效整合技术是将外源DNA片段插入到目的细胞基因组特定位置的一项转基因技术。早期通过细胞基因组与外源DNA同源序列发生重组来完成靶向整合的目的。伴随基因编辑技术发展,特别是CRISPR/Cas9技术的出现,精准高效的外源DNA整合技术日益成熟,广泛应用到功能基因组学、转基因动物及遗传疾病治疗的研究中。围绕基因编辑研究进展、引导RNA修饰技术、单碱基整合技术、转座子技术和外源DNA整合效率等方面对精准靶向和高效整合技术进行综述。