连翘干叶片和鲜叶片DNA提取方法和质量比较研究

Total Genomic DNA Extraction from Dried and Fresh Leaves of Forsythia Suspensa(Thunb.) Vahl and Quality Comparison

目的探讨三种DNA提取方法对连翘干叶片和鲜叶片DNA质量的影响,比较干叶片和鲜叶片DNA提取质量。方法采用常规CTAB法、高盐低pH法和新改良CTAB法提取连翘干叶片和鲜叶片DNA,进行A260/A280测定、琼脂糖凝胶电泳检测和RAPD扩增分析。结果新改良CTAB法提取的连翘干叶片和鲜叶片DNA的A260/A280比值在1.8～2.0之间,电泳条带清晰无拖尾,选用随机引物(S7)对上述DNA样品进行RAPD扩增,可获得具有一定多态性扩增谱带。对连翘干叶片和鲜叶片DNA样品综合比较,结果显示由干叶片获得的DNA质量高于鲜叶片。结论新改良CTAB法是一种分离高质量完整DNA的简便、快速方法,该方法得到的干叶片DNA质量较鲜叶片更适合下一步分子生物学研究。

Objective To explore the quality of genomic DNA from dried and fresh leaves of Forsythia suspense with three extraction methods of DNA,and to compare the DNA quality.Methods The CTAB,high salt and low pH method and new modified CTAB method were used to get DNA,and the ratio of A260/A280,agarose gel electrophoresis and RAPD amplification were tested.Results The A260/A280 ratios of DNA extracted by using the new modified CTAB method were between 1.8~2.0 and the agarose gel electrophoresis results showed that the bands of the DNA were both tight and distinct.Random primers（S7） was used in RAPD amplification of the DNA samples above and distinct bands of amplicates with some diversity were found.Compared with the DNA samples from fresh leaves,results showed that DNA quality from dried leaves was more higher.Conclusion New modified CTAB is a simple and fast method of the complete DNA in high quantity and DNA quality from dried leaves obtained by the method is more suitable for further studies of molecular biology than fresh leaves.