拟步甲昆虫基因组DNA提取的比较研究

对拟步甲科8种昆虫的新鲜标本及无水乙醇浸泡标本，分别用SDS-蛋白酶K消化法和乙酸钾抽提法进行基因组总DNA的提取．经5次重复实验，结果表明，用两种方法均能从新鲜标本中获得较完整的DNA，且DNA得率较高；而对于无水乙醇保存的标本，提取出的DNA用琼脂糖凝胶电泳检测不出DNA条带，说明标本在保存过程中DNA可能发生了变化，致使提取出的DNA量太少或未分离出DNA．通过对比实验，分析原因，阐明了两种方法的优缺点，并提出了该类昆虫用于DNA提取的标本的保存方法．     

瓢虫的16SrDNA序列扩增

提取酒精浸泡六斑月瓢虫标本的DNA,探讨酒精浸泡鞘翅目瓢虫科昆虫标本的核酸的提取方法,对提取得到的核酸进行PCR扩增,得到500bp大小的16SrDNA片段,确定这一方法提取的核酸进行PCR反应时的循环参数。     

固定标本的DNA提取及PCR扩增

报道富尔马林、酒精固定的日本绒螯蟹标本的ＤＮＡ提取及ＰＣＲ扩增，并与冷冻、煮沸标本进行了比较。结果表明，福尔马林固定标本与酒精固定标本一样可以撮加入的蛋白酶Ｋ量越多，ＤＮＡ的回收率越高。以提取的ＤＮＡ为模板，进行了线粒体ＤＮＡ１２ＳrＲＮＡ和Ｄ－１ooＰ基因片段的ＰＣＲ扩增，经琼脂糖产电泳ＰＣＲ扩增产物后均得到了与期待的碱基长度相一致的清晰谱带。     

一种简便高效的古代动物毛皮DNA提取方法

采用试剂盒QIAamp DNA Mini Kit从距今4000年前新疆小河墓地出土的黄牛毛皮中提取出古DNA,并对黄牛线粒体D-loop区部分片段进行了PCR扩增和序列测定.结果表明:所提取的古DNA真实可信;且该方法简便、高效,适用于古代动物毛皮DNA的提取.     

一种改进的昆虫基因组DNA的提取方法

就昆虫总DNA的提取,介绍了一种简便、快速的提取方法,此方法既可对新鲜标本进行DNA提取、也可对冷冻标本、干标本、酒精泡制标本进行DNA提取,均能得到较完整的大分子DNA片段,并且得率较高.改进的昆虫总DNA提取方法简便、快速,对设备和试剂的要求都不高.     

蚁科昆虫分子系统学研究进展

概述了蚁科昆虫分子系统学的研究进展，包括已测序的分类单元和序列片段，蚁科昆虫与其他远缘生物之间互利共生现象的比较研究，与蚁科昆虫相关的分子系统学研究方法的发展，并介绍用于分子系统学研究的昆虫标本的保存方法．     

从福尔马林固定的癌组织中提取RNA的方法

目的:寻求从福尔马林固定的癌组织中提取RNA的合理方法.方法:运用Trizol法从福尔马林固定的胃癌组织中提取RNA,用分光光度计测定RNA的产量和纯度;通过RT-PCR对不同长度的管家基因-actin进行扩增.结果:100 bp和300 bp的-actin均能顺利扩增出特异性条带,500 bp的-actin未能扩增.结论:用Trizol法从福尔马林固定的癌组织中提取RNA是可行的;进行RT-PCR时应尽量设计小片段引物(100~300 bp)以获得更好的扩增效果.     

鸟类陈旧标本DNA提取方法的研究

应用3种DNA提取方法(蛋白酶K法, Chelex 100法, 硅颗粒法),从馆藏湿地鸟类陈旧标本的羽毛、皮肤、骨骼组织中提取基因组DNA,经PCR扩增后对线粒体12S rDNA部分片段进行测序和Genbank查对,以探讨鸟类陈旧标本DNA的最佳提取方法和提取组织.结果表明,利用鸟类陈旧标本能够提取到基因组DNA.蛋白酶K法和硅颗粒法能够从白鹭(Egretta garzetta)标本的骨骼组织中提取到DNA并获得长度425 bp的线粒体12S rDNA序列(Genbank接收号AY766387),蛋白酶K法还能够从白鹳(Ciconia ciconia)标本的羽毛中获得长度263 bp的线粒体12S rDNA序列(Genbank接收号AY766388),Chelex 100法不能从鸟类标本中提取到DNA.蛋白酶K法的DNA提取量较大,但是步骤繁琐而导致DNA被污染的几率增大,因此,实验过程中要注意防止污染,且提取骨组织DNA要经过纯化.硅颗粒法的步骤简单,污染几率降低,提取骨骼组织DNA不需经过纯化,但是其DNA提取量较少,不能用于羽毛DNA的提取.因此,硅颗粒法是从鸟类陈旧标本骨骼组织提取DNA的理想方法,蛋白酶K法可用于鸟类陈旧标本羽毛的DNA提取.     

蝴蝶干标本DNA的提取及RAPD分析

通过对3种基因组DNA提取方法的实验比较,提出了适合蝴蝶干标本基因组DNA的提取方法,并成功地应用于RAPD-PCR的扩增,表明该方法可行．     

聚合酶链反应检测石蜡切片中金黄色葡萄球菌DNA的研究

目的　探讨聚合酶链反应技术 (PCR)在检测石蜡包埋组织中金黄色葡萄球菌DNA的应用及价值。方法　利用PCR技术 ,对 55例福尔马林固定、石蜡包埋小鼠组织中SA DNA进行了检测。结果　 55例石蜡包埋的小鼠组织中均检测到SA DNA ,这与临床病理诊断为金黄色葡萄球菌 (S .aureus)感染相一致。结论　PCR技术可用于检测石蜡包埋组织中的SA DNA片段 ,为鼠S .aureus感染的回顾性分析提供了有效手段     

中国漠王族干标本DNA提取及部分类群发育关系

为了降低昆虫分子系统学研究中的成本,提高资源利用率,本实验利用干制标本提取基因组DNA.通过对河北大学馆藏30年的漠甲亚科不同保存期干标本与液浸标本DNA的提取和特定基因片段PCR(聚合酶链式反应)扩增,获得一致效果.通过细胞色素B(Cytb)基因片段序列信息构建系统树并与传统分类学做比较,探讨了漠王族部分种类的系统进化关系,研究结果支持Reitter(1893)建立的Platyopini和Pimeliini是2个独立族的观点,而不同意Beutle等(2005)将它们合并为1个族的观点.研究结果为利用鞘翅目昆虫干标本进行分子系统学研究提供了借鉴.     

几种榕属(Ficus)植物标本的DNA提取及PCR扩增

植物标本作为一种非常重要的DNA资源受到越来越多的关注.由于其储存时间久远及储存手段局限,使得植物标本DNA提取和扩增相当困难.本研究以桑科榕属的9个种作为研究对象,采用4种DNA提取方法,比较其产物的数量和质量,并将所提取的DNA作为模版进行PCR扩增ITS和trnL-F片段.通过比较,得出以下结论:①标本的制作和储存条件对于植物标本DNA的质量有重要影响;②改进的CTAB法对于桑科榕属植物的DNA提取最为适合;③DNA模版的质量较之其他因素对PCR扩增的影响更大,适当缩短扩增片段的长度对实验的成功是至关重要的.     

不同保存方式下金龟甲虫DNA提取方法及28S rDNA序列分析

通过电泳检测和PCR扩增28SrDNA核基因序列的结果,比较了无水乙醇、75%乙醇、针插干制3种金龟甲虫标本的保存方式和SDS-蛋白酶K法、CTAB法、饱和NaCl法3种提取DNA方法.结果显示,SDS-蛋白酶K法、CTAB法提取3种保存方式的标本时,可成功提取DNA并有效扩增目的基因;饱和NaCl法仅能提取无水乙醇保存标本的DNA并扩增目的基因,而75%乙醇保存标本和干制标本的DNA提取和基因扩增均不理想.     

A pH-activatable fluorescent aptamer probe for imaging of target cancer cells

Early cancer diagnosis in molecular level shows great promise in relevant prevention and clinical treatment. Herein, we developed a novel method to detect and evaluate biomarkers on cancer cell surface. Based on the excellent selectivity of AS1411 aptamer to targeted nucleolin-overexpressed cells, we used a fluorescent probe with a pH-sensitive function to label the AS1411 aptamer modified with azide by click-reaction. The spectral characteristics of fluorophore naphthalimide has a good pH dependence. By this way, nucleolin-overexpressed cell could be discriminated from normal cell. Further, this strategy could also discriminate the breast cancer tissue from the adjacent benign tissue in formalin-fixed and parrffin- embedded (FFPE) tissue specimens. It is considered that our method has the potential to be applied in medical detection.     

Molecular identification and phylogenetic position of Cuora yunnanensis

The Yunnan box turtle (Cuora yunnanensis, Boulenger, 1906), which has drawn much attention in conservation biology, was regarded as extinct since it was previously known only from 12 specimens collected in Yunnan, China, before 1908. Recently, live specimens have been discovered which are suggested to be C. yunnanensis. To determine whether the newly discovered specimens are really C. yunnanensis, we have established a molecular phylogeny, with a 1725-bp fragment of mitochondrial DNA, using samples from three live individuals of C. yunnanensis, together with sequence data from a museum specimen of C. yunnanensis (MNHN 1907.10) and other members of the genus Cuora. We found that the three newly discovered individuals and the old museum specimen of C. yunnanensis are very similar both in morphology and in mitochondrial DNA sequence, suggesting that the three new individuals are the very C. yunnanensis, and thus the species is not extinct. Our phylogenetic analysis also demonstrates that C. yunnanensis is not of recent hybrid origin, but rather represents a distinct evolutionary lineage.     

Pitfalls in the analysis of ancient human mtDNA

The retrieval of DNA from ancient human specimens is not always successful owing to DNA deterioration and contamination although it is vital to provide new insights into the genetic structure of ancient people and to reconstruct the past history. Normally, only short DNA fragments can be retrieved from the ancient specimens. How to identify the authenticity of DNA obtained and to uncover the information it contained are difficult. We employed the ancient mtDNAs reported from Central Asia (including Xinjiang, China) as an example to discern potentially extraneous DNA contamination based on the updated mtDNA phylogeny derived from mtDNA control region, coding region, as well as complete sequence information. Our results demonstrated that many mtDNAs reported are more or less problematic.Startim, from a reliable mtDNA phylogeney and combining the available modern data into analysis, one can ascertain the authenticity of the ancient DNA, distinguish the potential errors in a data set, and efficiently decipher the meager information it harbored. The reappraisal of the mtDNAs with the age of more than 2000 years from Central Asia gave support to the suggestion of extensively (pre)historical gene admixture in this region.     

昆虫标本DNA提取的研究进展

昆虫标本是研究昆虫遗传变异的重要资源,在昆虫起源与进化和昆虫物种多样性研究中应用越来越广泛。本文综述了造成多年保存的昆虫标本DNA降解的原因,以及昆虫标本DNA的提取方法。