4种滑叶铁线莲基因组DNA提取方法比较(英文)

[目的]对4种滑叶铁线莲基因组DNA提取方法进行比较研究,建立滑叶铁线莲最适的DNA提取方法。[方法]以滑叶铁线莲叶片为材料,比较改良CTAB法Ⅰ、改良CTAB法Ⅱ、改良CTAB法Ⅲ、改良SDS法这4种基因组DNA提取法在提取的DNA纯度、浓度和提取时间等方面的不同。[结果]4种方法都可提取滑叶铁线莲基因组DNA。改良CTAB法Ⅰ提取DNA纯度最高,但浓度最低且提取时间最长;改良SDS法提取DNA浓度最高,所需时间较短,但纯度较低;改良CTAB法Ⅲ提取所需时间最短。[结论]建立了铁线莲最适DNA提取方法,为运用分子生物学手段对其研究提供支持。     

橡胶树MSAP反应体系的建立及其对无性系DNA的甲基化分析

采用改良CTAB法提取橡胶树幼嫩叶片的基因组DNA,通过电泳检测酶切与连接、预扩增和选择性扩增等,建立橡胶树MSAP甲基化敏感扩增多态性(MSAP)分析体系,并利用MSAP技术在基因组水平上对橡胶树幼态优势的形成机理进行研究。结果表明:利用该体系可获得扩增位点多、条带清晰、重复性好的图谱(共扩增出740个条带,404个甲基化位点,平均多态性比例为54.6%),并能有效区分基因组DNA甲基化的状态,为开展橡胶树同一品种不同类型种植材料的表观遗传变异研究奠定了基础。     

金黄色葡萄球菌基因组DNA提取方法的比较

为寻求一种较为实用的金黄色葡萄球菌（Staphylococcus aureus）基因组DNA提取方法,对酶解法、十二烷基硫酸钠（Sodium dodecyl sulfate,SDS）法、FDA法、热裂解法等常见的4种不同提取方法进行了改良和比较.结果表明,4种方法中,SDS法提取的DNA质量最好,检测灵敏度高,当金黄色葡萄球菌的DNA稀释至2.95 pg或更少时,SDS法还能够通过PCR将其检测出来;并且该方法的稳定性好,经济性高,是金黄色葡萄球菌基因组DNA理想的提取方法.     

Role of exogenous phytohormones on growth and plumbagin accumulation in Plumbago indica hairy roots and conservation of elite root clones via synthetic seeds

The present study describes the role of different exogenous hormones on morphology and plumbagin production in Plumbago indica hairy roots. It was also aimed to conserve elite root clones via synthetic seed technology. Insertion of rolB gene in transformed roots was confirmed by polymerase chain reaction followed by southern blot analysis. Hairy roots were treated with single or in combination of different phytohormones viz. IAA, IBA, 2, 4-D, NAA, BAP, GA₃ and ABA. Cultures incubated with GA₃ (0.5 mg l⁻¹) yielded highest root growth due to formation of profuse lateral branching while NAA (0.5 mg l⁻¹) treatment caused highest plumbagin accumulation. Cultures incubated with 2, 4-D exhibited highest inhibitory effect in terms of both root growth and plumbagin production. All phytohormones were found to be effective at lower concentration. In combinatorial study, GA₃ + NAA (0.5 mg l⁻¹, each) was found optimum for root biomass and plumbagin production at earlier stage of culture. Different combinations of auxins and BAP induced different morphologies ranging from reduction of lateral branching to rapid disorganization of root matrix. The combinations of ABA and selected auxins were not found promising at any of selected concentration. Based on the effect of exogenous hormones on hairy root culture, elite root clones were selected and encapsulated with sodium alginate matrix. Uniform shaped alginate coated synthetic seeds were conserved up to 6 months exhibited high regeneration potential without disturbing plumbagin content.     

生物芯片应用与发展

生物芯片具有高通量、高信息量、快速、所需样品少等优点,已经成为科学研究的热点之一。本文介绍生物芯片的概念,并综述4种生物芯片的主要应用领域及应用现状,同时分析生物芯片技术中存在的问题。尽管生物芯片受到很多相关技术的制约,但仍具有非常广阔的应用前景。     

芭蕉属植物cpDNAL16序列限制性片段长度多态性研究

采用限制性内切酶Sau3AI、MspI、TaqαI、AluI分别对获得的L16基因序列进行理论酶切。通过限制性内切酶酶切后,酶切片段大小相同的记为1,不同的记为0。相似系数和聚类分析应用NTSYS-pc2.01数据分析软件进行,采用Nei的方法计算相似系数,UPGMA方法聚类,绘制树状图。结果表明芭蕉属种间存在较为丰富的cpDNA PCR-RFLP多态性,种内差异性不明显,有些亚种间无法区分开。而M. acuminata 具有丰富的亚种和变种,遗传差异大,多样性丰富。     

木材DNA条形码鉴定研究进展

木材种属鉴定具备显著的生物学与经济意义, 但传统的以显微特征观察为主的方法已不能适应高通量和精细化鉴别的需要。DNA条形码是根据特定基因片段的序列差异, 利用生物信息学技术对生物物种进行快速分类与鉴别的方法。近年来, DNA条形码技术已被陆续应用于木本植物及相应木材的种质鉴定, 在目标基因选择、木材DNA提取及生物信息学分析等方面均取得显著进展。在使用优化的微量DNA提取技术的前提下, 干燥木材中也可提取出满足扩增要求的DNA。经过生命条形码联盟等国际机构的长期努力, 确定了rbcL+ matK组合等通用植物条形码标记及ITS2等补充标记, 并建立了BOLD等数据库系统。传统的条形码序列分析主要通过BLAST比对、遗传距离分析及系统进化分析来实现, 近年来随着生物信息学的发展, DNA条码数据库不断完善, 新的数据分析方法和软件正不断涌现。文中在总结现有研究成果和实施规范的基础上, 综述国内外应用DNA条形码技术进行木材鉴别的新进展, 并着重阐述新型序列分析方法和相应的生物信息学工具。     

濒危竹种小蓬竹（Drepanostachyum luodianense） RAPD PCR反应体系优化

为了建立小蓬竹（Drepanostachyum luodianense） RAPD PCR反应的最优体系,以小蓬竹基因组DNA为模板,对影响其RAPD扩增的dNTPs浓度、模板DNA浓度、Taq DNA聚合酶量、引物浓度、Mg2+浓度等重要参数进行了单因子和正交试验。试验得出小蓬竹RAPD最优反应体系为: 20 μL反应体系,10×PCR buffer为1/10体积,dNTPs为100 μmol·L-1,模板DNA量为30 ng,Taq DNA聚合酶为10 U,引物浓度为02 μmol·L-1,Mg2+浓度为15 mmol·L-1。优化后的RAPD PCR反应程序为: 94℃预变性5 min,然后进入35个循环,即94℃变性1 min,35℃退火30 s,72℃延伸90 s,循环完毕后于72℃延伸7 min,最后在4℃保持。     

Molecular Taxonomy of Conogethes punctiferalis and Conogethes pinicolalis (Lepidoptera: Crambidae) Based on Mitochondrial DNA Sequences

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. pinicolalis and C. punctiferalis are significantly different.     

Global Analysis of Cytosine Methylation and Proteome Under Cold Treatment in Brassica napus

Cytosine methylation/demethylation plays pivotal roles in regulating gene expression at a genome-wide level. However, limited reports are available to reveal correlating changes of cytosine methylation and proteomic expression in Brassica napus so far. Therefore, in the present study, global cytosine methylation and proteome were analysed in B. napus after cold treatment by methylation-sensitive amplified polymorphism （MSAP） and two-dimensional protein electrophoresis technology （2-DE）. The results showed that the lowered genome-wide DNA methylation status was revealed after cold treatment, and about 0.88% of discrepancy in DNA methylation was detected between the non-flowering and flowering plants after cold treatment. Moreover, the 52 significantly up-regulated proteins emerged in comparison with the 36 down-regulated proteins, as well as the 14 proteins exclusively detected in the flowering plants. Intriguingly the 8 specifically expressed proteins in the non-flowering plants disappeared in the flowering plants with cold treatment. Therefore, these present data proved that the correlating changes of cytosine methylation and proteomic expression were evidenced under cold treatment in B. napus.