高质量植物基因组DNA的分离

Isolation of high-quality genomic DNA from plants

为了从富含多酚和多糖的药用植物组织中分离出高质量基因组DNA ,本文通过改良几种已经存在的分离方法 ,获得了一种以CTAB法为基础的分离高质量完整DNA的简便、快速方法。使用该方法从人参、西洋参及三七的新鲜或干燥根组织分离DNA时 ,A2 60 /A2 80 为 1.8左右 ,分子量大小约为 2 1.2kb ,由此所得的DNA可直接用于AFLP分析 ,即用EcoRⅠ /MseⅠ消化DNA后 ,用DNA的限制酶切片段经T4DNA连接酶连接 ,再用巢式PCR扩增 ,构建出可重复的、多态性丰富的人参、西洋参、三七基因组DNAAFLP指纹图谱。结果表明 ,该技术可有效地从富含多酚和多糖的药用植物组织中分离出高质量和高分子量DNA ,此法亦有望用于其它植物DNA的分离。

In order to isolate high quality genomic DNA from medicinal plant tissues enriching polyphenols and polysaccharides, a simple and rapid method based on CTAB extraction for isolating high quality intact DNA was established by modifying several existing methods. With this technique, the absorbance ratio (A 260 /A 280 ) of DNAs obtained from fresh and /or dried roots of Panax ginseng, P. Quinquefolius and P. notoginseng was 1.8 approximately. The restriction fragments of DNAs were directly digested with restriction enzyme (EcoRⅠ/MseⅠ), linked up by T 4DNA ligase and amplified by nested PCR. Reproducible amplified fragment length polymorphism (AFLP) genomic DNA fingerprinting profiles were established with the isolated DNAs. The results demonstrate that the modified technique may be efficient and reliable in isolating high quality and high molecular weight DNAs from fresh and/or dried medicinal plants containing a high content of polyphenols and polysaccharides. We expect that this method can also be applied to other plants.