直接从人工老化的菜心干种子中提取基因组DNA用于RAPD分析

利用 4 0℃、1 0 0 %RH对菜心种子进行人工加速老化处理获得了不同活力的种子批 ,利用平衡酚_氯仿法直接从人工老化的菜心干种子中提取基因组DNA ,并对提取的基因组DNA进行了RAPD扩增。结果表明 ,所提取的基因组DNA量多 ,而且比较整齐一致。引物S2 0 8扩增所获得的基因组DNA指纹图谱上的DNA带清晰、明亮 ,从而表明利用本方法从人工老化菜心干种子中直接提取的基因组DNA完全可以用于RAPD分析。     

丝状真菌组织DNA的提取

用CTAB法直接从丝状真菌的新鲜菌丝中提取DNA,并将所提取DNA进行随机引物多态性扩增(RAPD),得到了较清晰的扩增图谱,证明该法为提取真菌DNA以用于分子生物学研究的一种有效方法。     

直接从人工老化的菜心干种子中提取基因组DNA用于RAPD分析

利用40℃、100％朋对菜心种子进行人工加速老化处理获得了不同活力的种子批,利用平衡酚-氯仿法直接从人工老化的菜心干种子中提取基因组DNA,并对提取的基因组DNA进行了趾PD扩增。结果表明,所提取的基因组DNA量多,而且比较整齐一致。引物S208扩增所获得的基因组DNA指纹图谱上的DNA带清晰、明亮,从而表明利用本方法从人工老化菜心干种子中直接提取的基因组DNA完全可以用于RAPD分析。     

RAPD分析用白花丹参叶片DNA的提取方法

本研究采用改良CTAB法和SDS法提取新鲜白花丹参叶片的基因组DNA,初步筛选RAPD扩增引物。结果表明改良CTAB法提取的DNA较SDS法质量好,随机引物p2扩增条带相对较为清晰。再利用p2随机引物对2种方法提取的DNA进行RAPD检测比较,结果显示仅改良CTAB法能扩增出有效条带,说明改良CTAB法更适合用于白花丹参基因组DNA的RAPD检测分析。本文将为白花丹参叶片DNA的提取提供方法学参考。     

利用CTAB法和子囊孢子破壁法提取冬虫夏草菌DNA

通过CTAB法从冬虫夏草菌株和天然冬虫夏草不同部位提取DNA,并用PCR扩增进行验证,证明了CTAB法适合从冬虫夏草子座、菌核和冬虫夏草菌培养物中提取DNA。首次报道1种将子囊孢子破壁直接进行PCR扩增的方法,并比较了该方法和CTAB法在提取冬虫夏草DNA方面的差异。2种方法获得的DNA用于PCR扩增均能得到较好的结果。     

由小麦赤霉病菌菌丝快速提取DNA用于PCR扩增反应

采用加玻璃珠混合振荡1800r／min15分钟并95℃水浴加热10～20分钟的物理破壁方法由真菌菌丝直接提取DNA用于PCR扩增,具有所提DNA可扩增性好、提取方法简便易行、便宜等优点。相同引物或不同引物的二次扩增产物均好于一次扩增,且以引物B1和B3扩增后再用引物Fg1和Fg2扩增的效果最好。此法可广泛应用于大量样品的PCR和RAPD扩增实验。     

FTA-DNA直接提取法在病原真菌分子鉴定中的应用

目的建立并评价FTA-DNA直接提取法在病原真菌分子鉴定中的应用。方法采用whatman FTA-DNA直接提取法从25个不同种属的45株培养的菌株和6例临床标本中提取病原真菌DNA,用于病原真菌的测序鉴定。配制不同浓度的孢子悬液探索该方法的检测限和安全性。结果 45株菌株扩增后均能得到1条清晰的DNA扩增片段,并成功测序。应用该方法亦成功从腹水、胸水、口腔拭子、宫颈拭子来源的临床标本中直接提取DNA并成功鉴定病原真菌。该DNA提取方法联合降落PCR能检测到1.0×103个cell/mL的孢子悬液,1.0×104个cell/mL及以下浓度的孢子悬液可以被FTA卡完全灭活。结论 FTA-DNA直接提取法可快速有效地从培养的菌株及部分临床标本中提取并保存病原真菌DNA,用于病原真菌的测序鉴定。     

高温环境样品总DNA直接和间接提取方法的比较

分别采用两种环境总DNA直接提取法和一种间接提取法从6种温泉菌席样品中提取总DNA,以DNA粗产物的纯度、能否用于后续PCR扩增及PCR-DGGE(变性梯度凝胶电泳)所反映的微生物多样性为评价指标对两类方法进行比较和评价。研究发现,虽然间接提取法效率低下,但对于高温极端环境中生物量较小的样品,间接法能得到有研究价值的、纯度较高的环境样品总DNA,而直接法得到的DNA量小且不适于PCR扩增操作。在使用这2类方法都能得到可用于研究操作的DNA的情况下,间接提取法能更好的体现环境样品中微生物的多样性。     

穿山甲标本和甲片的DNA提取及PCR扩增

为验证经处理后的穿山甲(Manis spp.)标本和甲片是否可以用于种间分子鉴定标记的开发及个体识别工作,本文在样品的预处理、消化、提取后纯化等方面对传统提取方法进行了改进,分别从穿山甲剥制标本、干皮标本及甲片中提取总DNA;然后用Cyt b基因扩增通用引物、12S rRNA基因全序列扩增引物、RAPD引物及微卫星引物进行了PCR扩增,并对部分扩增结果进行了序列测定.结果表明,除剥制标本的脚底皮张组织外,其他样品基本都可以提取出DNA.以此为模板的PCR扩增中,2种线粒体基因引物扩增出明显目的条带,RAPD引物扩增出种间特异条带,测序结果可用于种间特异性引物及SCAR引物的开发;微卫星引物在甲片样品中扩增稳定,可用于个体识别工作.     

RAPD技术在黑糯玉米亲缘关系划分上的应用

以8个黑糯玉米自交系为试验材料,利用CTAB微量提取法从幼苗中提取DNA,进行RAPD扩增,筛选出3个能产生稳定遗传多态性的引物,分别是OP—A01、OP—A11和OP-006;利用这些引物的扩增出的指纹图谱,进行聚类分析,可将8个自交系划分为4个类群,与各个自交系的来源基本一致。表明RAPD可以用于黑糯玉米亲缘关系的划分。     

向日葵单染色体显微分离及特异文库的构建

采用玻璃针分离法,通过显微操作系统成功地分离到内葵杂3号三交种和单交种的随体染色体,经两轮LA．PCR扩增得到250～1500bp的DNA片段。用各自的基因组DNA标记成探针,与随体染色体扩增产物进行Southern杂交,显示杂交信号,证明内葵杂3号三交种和单交种随体染色体DNA已被成功扩增。将第2轮PCR产物构建质粒文库,得到三交种和单交种克隆数分别约为2．26×10^5和2．57×10^5。各随机挑取30个重组子进行分析,发现插入片段大小分别为200-700bp和200～500bp,平均插入片段大小分别为535bp和480bp。这是染色体微分离与微克隆技术首次在向日葵上的应用。     

Proboscidean DNA from Museum and Fossil Specimens: An Assessment of Ancient DNA Extraction and Amplification Techniques

Applications of reliable DNA extraction and amplification techniques to postmortem samples are critical to ancient DNA research. Commonly used methods for isolating DNA from ancient material were tested and compared using both soft tissue and bones from fossil and contemporary museum proboscideans. DNAs isolated using three principal methods served as templates in subsequent PCR amplifications, and the PCR products were directly sequenced. Authentication of the ancient origin of obtained nucleotide sequences was established by demonstrating reproducibility under a blind testing system and by phylogenetic analysis. Our results indicate that ancient samples may respond differently to extraction buffers or purification procedures, and no single method was universally successful. A CTAB buffer method, modified from plant DNA extraction protocols, was found to have the highest success rate. Nested PCR was shown to be a reliable approach to amplify ancient DNA templates that failed in primary amplification.     

Rationalizing molecular analysis of field-collected roots for assessing diversity of arbuscular mycorrhizal fungi: to pool, or not to pool, that is the question

For rationalizing molecular analysis of field-collected roots in diversity studies on arbuscular mycorrhiza, we compared three different approaches. After DNA extraction from 50 root samples of Plantago lanceolata grown on monoculture plots at a former arable field site, (1) DNAs were amplified separately by nested PCR and each amplicon was cloned separately; (2) DNAs were amplified separately by nested PCR, 1 μl of each amplicon was pooled, and a single cloning was made from the resulting amplicons mix; and (3) DNAs were pooled and the single amplicon derived from the nested PCR was cloned. Based on these three different methods, 109 nuclear ribosomal internal transcribed spacer sequences were obtained. Methods 1 and 2 enabled the detection of almost similar levels of arbuscular mycorrhizal fungal diversity. However, method 1 was expensive and time-consuming as much more cloning had to be done. Method 3 was completely biased by preferential amplification of nontarget organisms, which were only detected in low frequencies by the other methods.     

1种小麦白粉病菌DNA基因组的微量简捷提取方法

为了寻找适合小麦白粉菌基因组DNA微量提取的方法,分别采用改进破壁法,液氮研磨法和溶菌酶消化法进行破壁,提取专性寄生菌小麦白粉菌DNA。结果表明,用改进的破壁方法,仅用3~10 mg的分生孢子粉所获得DNA的收率为（12.23±3.46）~（40.32±5.67）ng/mg,且OD260/OD280比值为1.71~1.92之间,说明该破壁方法获得的DNA收率大且纯度高。通过PCR反应获得了良好的效果。同时该方法也适用于小麦条锈菌和大麦白粉菌专性寄生菌DNA的提取。     

向日葵品种鉴定和纯度分析的AFLP研究

从杂交油葵A15及其亲本的1/2粒干种子中提取基因组DNA,选用17对引物组合进 行AFLP分析,构建了它们的指纹图谱。17对引物在A系与R系当中共扩增出1125条扩增产物,其中144条带表现出多态性,平均每对引物扩增66条带,不同引物组合产生的DNA片段数目在50～70之间,大小分布于100bp～500bp,多态性比率为12.8%。从中筛选出的2对引物E_AAC/M_CTC和E_ACG/M_CTG可将亲本和子代区分开：引物对E_AAC/M_CTC在A系中扩增出440bp、190bp、160bp 3条特征谱带,在R系中扩增出380bp、350bp、225bp、180bp 4条特征谱带,E_ACG/M_CTG在A系中扩增出了2条特征带480bp和265bp,在R系中扩增出490bp、220bp、205bp、125bp 4条特征谱带,且上述谱带均在子代中出现。用引物组合E_ACG/M_CTG对A15、双亲以及与A15外型十分相似的10个常用油葵杂交种进行AFLP分析,不仅表现出良好的多态性,并能够清楚地将它们加以区分。以其对50粒A15杂交种子进行纯度鉴定,得到与大田纯度检测一致的结果,说明使用AFLP标记检测油用向日葵的品种和纯度是可行的。对现行种子纯度和品种鉴定的方法进行了讨论。     

Efficient Detection of Leptosphaeria maculans from Infected Seed lots of Oilseed Rape

An efficient DNA extraction protocol and polymerase chain reaction (PCR) assay for detecting Leptosphaeria maculans from infected seed lots of oilseed rape were developed. L. maculans, the causal agent of blackleg, a damaging disease in oilseeds rape/canola worldwide, was listed as a quarantine disease by China in 2009. China imports several millions of tons of oilseeds every year. So there is a high risk that this pathogen will be introduced to China via contaminated seeds. Seed contamination is one of the most significant factors in the global spread of phytopathogens. Detection of L. maculans in infected seed lots by PCR assay is difficult due to the low level of pathogen mycelium/spores on seeds and PCR inhibitors associated with the seeds of oilseed rape. In our study, these two major obstacles were overcome by the development of a two‐step extraction protocol combined with a nested PCR. This extraction protocol (kit extraction after CTAB method) can efficiently extract high‐quality DNA for PCR. Amplification results showed that the detection threshold for conventional PCR and nested PCR was, respectively, 1 ng and 10 fg of DNA per μl in mycelia samples. On contaminated seed lots of oilseed rape, the detection threshold of conventional and nested PCR was 709 fg/μl and 709 ag/μl of DNA, respectively. The DNA extraction protocol and PCR assay developed in this study can be used for rapid and reliable detection of L. maculans from infected seeds of oilseed rape .     

Novel method for preparation of the template DNA and selection of primers to differentiate the material rice cultivars of rice wine by PCR

As many rice wine brewers label the name of the cultivar of the material rice, authentication technology is necessary. The problems are (1) decomposition of DNAs during the fermentation, (2) contamination of DNAs from microorganisms, (3) co-existence of PCR inhibitors, such as polyphenols. The present authors improved the PCR method by (1) lyophilizing and pulverizing the rice wine to concentrate DNAs, (2) decomposition of starches and proteins so as not to inhibit DNA extraction by the use of heat-resistant amylase and proteinase K, (3) purification of the template DNA by the combination of CTAB method and fractional precipitation by 70% EtOH. To prevent the amplification of microorganism's DNAs during PCR, the present authors selected the suitable plant-specific primers. It became possible to prepare the template DNAs for PCR from the rice wine. The sequences of the amplified DNAs by PCR were ascertained to be same with those of material rice. Mislabeling of material rice cultivar was detected by PCR using the commercial rice wine. It became possible to extract and purify the template DNAs for PCR from the rice wine and to differentiate the material rice cultivars by the PCR using the rice wine as a sample.     

Optimization of microbial DNA extraction and purification from raw wastewater samples for downstream pathogen detection by microarrays

Numerous waterborne pathogens are difficult to detect and enumerate with accuracy due to methodological limitations and high costs of direct culturing. The purity of DNA extracted from wastewater samples is an important issue in the sensitivity and the usefulness of molecular methods such as polymerase chain reaction (PCR) and hybridizations on DNA microarrays. Ten different DNA extraction procedures, including physical and chemical extraction and purification steps, were examined to ascertain their relative effectiveness for extracting bacterial DNA from wastewater samples. The quality of the differentially extracted DNAs was subsequently assessed by PCR amplification and microarray hybridization. Our results showed that great differences existed among the ten procedures and only a few of the methods gave satisfactory results when applied to bacterial pathogens. This observation suggested that the extraction method needed to be carefully selected to produce significant and confident results in the detection of pathogens from environmental samples.     

快速、高效的羊绒羊毛织品DNA提取方法的建立

目的：建立一种快速、高效的羊绒羊毛纺织品DNA提取的方法。方法：采用chelex-100法的3种处理、试剂盒法分别提取羊绒羊毛织品的DNA,用18S rDNA片段、山羊和绵羊源性成分PCR扩增结果来比较提取效果。结果：试剂盒法提取DNA的效果优于chelex-100法,整个提取过程约需2h。9种供试材料均提取到DNA,且含有山羊和/或绵羊源性成分,与显微镜观察结果的符合率为100%。结论：建立的试剂盒法是一种快速、高效的适用于羊绒羊毛织品DNA提取的方法,为应用分子生物学方法鉴别山羊绒和绵羊毛奠定了基础。     

A Rapid DNA Extraction Method for RFLP and PCR Analysis from a Single Dry Seed

A single-seed DNA extraction method was developed for rapid identification of plant genotype. The method was applied to 12 plant species, including the oil seeds sesame and soybean. The results were comparable to those obtained for oil-less seeds such as rice. This method will be useful for genotypic selection which requires rapid screening of large populations. It can also be used to identify varietal purity of seed stocks by PCR and RFLP analysis. The method includes two major steps, (i) treatment by proteinase K in an SDS extraction buffer, and (ii) grinding of a single half seed in the buffer after incubation. About 1.5–2 µg of DNA per half seed (the endosperm part) of rice was obtained and more than 200 half seed samples could be handled by one person in a day. The DNA could be used for fingerprinting and detection of target genes in a transgenic plant by PCR. The amplified PCR products from the half seed DNA exhibited the same banding patterns as those from leaf DNA. Yield and quality of DNA extracted from half seeds of rice was also sufficient for RFLP analysis. The remnant half seeds containing the embryo can be maintained for later germination of selected genotypes.