植物荧光原位杂交技术的发展及其在植物基因组分析中的应用

荧光原位杂交(FISH)是在染色体、间期核和DNA纤维上定位特定DNA序列的一种有效而精确的分子细胞遗传学方法。20年来,植物荧光原位杂交技术发展迅速:以增加检测的靶位数为目的,发展了双色FISH、多色FISH和多探针FISH鸡尾酒技术;为增加很小染色体目标的检测灵敏度,发展了BAC-FISH和酪胺信号放大FISH(TSA-FISH)等技术;以提高相邻杂交信号的空间分辨力为主要目的,发展了高分辨的粗线期染色体FISH、间期核FISH、DNA纤维FISH和超伸展的流式分拣植物染色体FISH技术。在植物基因组分析中,FISH技术发挥了不可替代的重要作用,它可用于:物理定位DNA序列,并为染色体的识别提供有效的标记;对相同DNA序列进行比较物理定位,探讨植物基因组的进化;构建植物基因组的物理图谱;揭示特定染色体区域的DNA分子组织;分析间期核中染色质的组织和细胞周期中染色体的动态变化;鉴定植物转基因。

Progress of Plant FISH Technique and Its Applications in the Analysis of Plant Genome

Fluorescence in situ hybridization(FISH) is an effective and accurate molecular cytogenetic tool for mapping specific DNA sequences on chromosomes,interphase nuclei and DNA fibers.Rapid advances in plant FISH technique have been made in the past two decades.Dual FISH,multicolor FISH and multiprobe FISH cocktail have been developed to increase the number of detected targets;BAC-FISH and tyramide signal amplification FISH(TSA-FISH) have been applied to increase the detection(sensiti-)(vity) of very small chromosomal targets;and high resolution FISH such as pachytene FISH,interphase FISH,fiber FISH and FISH on super-stretched flow-sorted plant chromosome have been developed mainly to improve the spatial resolution of signals derived from flanking sequences.FISH have played important roles in the analysis of plant genome.It can physically map specific DNA sequences,provide effective marks for chromosome identification within a genome,investigate the evolution of plant genome by comparative mapping of the same DNA sequences in related species,construct the physical map of plant genome,directly reveals the DNA molecular organization of a specific chromosome regions,analyze the organization pattern of interphase chromatin and the dynamic changes of chromosomes in cell cycle,and characterize transgenes in plant genomes.