染色体制备与识别技术是遗传学研究的重要手段, 而寡核苷酸荧光原位杂交(oligo-FISH)是近年来兴起的染色体识别技术。灵活高效的探针是荧光原位杂交过程中的关键因素。传统的单链寡核苷酸探针标记过程复杂, 且获得单个探针的成本较高。在单链寡核苷酸探针的基础上进行改良, 利用靶向全染色体(片段)的特异性引物进行扩增, 将获得产物纯化, 即可得到目的探针, 简化了探针标记过程, 降低了成本, 并提高了标记效率。该文详述了水稻(Oryza sativa)改良后的双链寡核苷酸探针文库的合成及标记方法、有丝分裂时期染色体制片和探针杂交过程。通过设计梯度实验发现水稻中寡核苷酸荧光原位杂交技术染色体和寡核苷酸探针的最佳变性时间与温度分别为85°C 3分钟30秒及90°C 6分钟。该研究在水稻中建立染色体双链寡核苷酸荧光原位杂交技术, 可为多种植物染色体制备与精准识别提供有力的工具。

The technique of identification and preparation of chromosome(s) are important tools in genetic research. Oligonucleotide fluorescence in situ hybridization (oligo-FISH) is an emerging chromosome identification technique in recent years. Flexible and efficient probes are the key factors in the process of oligo-FISH. The labelling process of traditional single-stranded oligo probes (ss-oligos) is complicated and the cost of obtaining individual probes is high. By improving the ss-oligo probes labelling process, we obtain the probes by PCR amplification with specific primers targeting the whole chromosome (fragment), which simplifies the probe labelling process, reduces the cost and improves the labelling efficiency. In this study, we describe in detail the synthesis and labelling of a modified double-stranded labelled oligo probes (ds-oligos) library in rice (Oryza sativa), the preparation of mitotic chromosomes and the hybridization process of ds-oligo probes. By designing gradient experiments, the optimal denaturation time and temperature of chromosome and oligo probe in rice were found to be 85°C for 3.5 min and 90°C for 6 min, respectively. This is the first study to establish a chromosomal double-stranded labelled oligo-FISH system in rice, which provides a powerful tool for the preparation and precise identification of chromosomes in a variety of plants.