玉米DNA纤维的制备及端粒DNA的Fiber-FISH  

Preparation of DNA Fiber in Maize and Fiber-FISH of Telomere DNA

作　　者：赵丽娟[1] 刘良科[1] 李立家[2] 

机构地区：[1]怀化学院生物工程系,湖南怀化418008 [2]武汉大学生命科学学院植物发育生物学教育部重点实验室,湖北武汉430072

出　　处：《安徽农业科学》2008年第6期2251-2252,2258,共3页Journal of Anhui Agricultural Sciences

摘　　要：[目的]建立了一种快速制备DNA纤维的方法,用端粒DNA在玉米纤维上进行物理定位。[方法]采用刀切法从玉米嫩叶中提取细胞核。以端粒DNA为探针,在玉米DNA纤维上进行伸展DNA纤维的荧光原位杂交（Fiber-FISH）,研究端粒DNA重复序列在玉米染色体上的拷贝数。[结果]用刀切法提取玉米细胞核,提高了核的完整性,并改善了DNA纤维的制备效果。玉米细胞核裂解的最佳时间为8-9 min。玉米的Fiber-FISH试验结果表明,杂交信号为伸展的念珠状长链,玉米各条染色体端粒DNA的长度为7-103μm,各染色体端粒重复序列的拷贝数存在显著差异（为15~230 kb）。[结论]玉米各染色体中端粒的长度可能不同,而且随着玉米生长及环境的变化,各条染色体端粒DNA长度的变化也不一致。[Objective] The research aimed to establish a rapid preparation method of DNA fiber and use telomere DNA for physical location on maize fibers.[Method] Cell nucleus were extracted from tender leaves of maize by jackknife method.With telomere DNA as probes,the extended DNA fiber fluorescence in situ hybridization（Fiber-FISH） was made on DNA fiber in maize to study the copy number of the repeated sequences of telomere DNA on maize chromosome.[Result] Extracting cell nucleus from maize by jackknife method increased the integrality of nucleus and improved the preparation effects of DNA fibers.The optimum time for the cracking of cell nucleus in maize was 8～9 min.The results of Fiber-FISH test in maize indicated that the hybridization signal was the extended moniliform long chain,the length of telomere DNA in each chromosome of maize was 7～103 μm and the copy numbers of the repeated sequences of telomere among each chromosome had significant differences（15～230 kb）.[Conclusion] The telomere length in each ch romosome of maize was possibly different.With the growth of maize and the changes of the environment,the changes of telomere DNA in each chromosome were also inconsistent.

关 键 词：玉米 端粒DNA纤维荧光原位杂交 拷贝数 

分 类 号：S513[农业科学—作物学]