利用不同植物进行DNA损伤彗星实验的方法比较

为了研究彗星实验在植物DNA损伤检测中的应用,以多种植物材料为对象,进行了植物彗星实验的比较研究.分别分离了蚕豆、菠菜、洋葱、菜豆、大蒜、水稻等植物组织的细胞核,并以彗星实验方法研究了H2O2引起的植物细胞核DNA损伤.电泳后发现H2O2处理组植物细胞核出现明显拖尾,而对照组没有出现拖尾或拖尾较小.研究结果表明彗星实验是一种可以在单细胞水平上研究植物DNA损伤程度的手段,具有灵敏、简单、快速的优点.采用合适的细胞核分离方法,能够将彗星实验应用于多种植物,研究其DNA损伤.蚕豆、菠菜、洋葱、菜豆、大蒜等植物的根尖和叶片都可以应用于植物彗星实验,但在本实验条件下利用水稻组织进行彗星试实验并没有获得明显的彗星图像,能否进行彗星实验可能受植物本身性质或实验条件等多种因素的影响.

A Comparation Study Using Comet Assay to Detect DNA Damages in Different Plant Species

The comet assay using plant nuclei isolated from different plant species was proved to be a promising tool for genotoxicity assay. The plant nuclei isolated from the roots or the leaves of Vicia faba,Spinacia oleracea,Allium cepa,Phaseolus vulgaris,Allium sativum,and Oryza sativa were used in the comet assay to detect DNA damage induced by H2O2. After electrophoresis the nuclei from plants treated with H2O2 showed a large number of DNA strand breaks and appeared as clear comets whereas the control nuclei appeared nearly circular or with only slight comet tails. The comet assay using plant materials could quantify DNA damages in genotoxicity study of chemicals and chemical mixtures. The comet assay has been successful for Vicia faba,Spinacia oleracea,Allium cepa,Phaseolus vulgaris and Allium sativum,but had some problems for Oryza sativa. The use of comet assay has some limitations so a further study should be done to improve the method. In conclusion it was proved that the comet assay using plant nuclei is a fast,reliable,and inexpensive test as sensitive as the comet assay using animal cells to detect DNA strand breaks in some plants.