Yokota H, van den Engh G, Mostert M, Trask B J
Department of Molecular Biotechnology, University of Washington, Seattle 98195, USA.
Genomics. 1995 Jan 20;25(2):485-91. doi: 10.1016/0888-7543(95)80049-r.
Interphase fluorescence in situ hybridization (FISH) has been shown to be a means to map DNA sequences relative to each other in the 100 kb to 1-2 Mb genomic-separation range. At distances below 0.1 Mb, probe sites are infrequently resolved in interphase chromatin. In the 0.1- to 1-Mb range, interphase chromatin can be modeled as a freely flexible chain. The mean square interphase distance between two probes is proportional to the genomic separation between the probes on the linear DNA molecule. Above 1-2 Mb, the relationship between interphase distance and genomic separation changes abruptly and appears to level off. We have used alkaline-borate treatment to expand the capability of interphase FISH mapping. We show here that alkaline-borate treatment increases nuclear diameter, the interphase distance between probes on homologous chromosomes, and the distance between probes on the same chromosome. We also show that the mean square distance between hybridization sites in borate-treated nuclei is proportional to genomic separation up to 4 Mb. Thus, alkaline-borate treatment enhances the capability of interphase FISH mapping by increasing the absolute distance between probes and extending the range of the simple relationship between interphase distance and genomic separation.
间期荧光原位杂交（FISH）已被证明是一种在100 kb至1 - 2 Mb基因组间隔范围内绘制相对DNA序列图谱的方法。在距离低于0.1 Mb时，探针位点在间期染色质中很少能分辨出来。在0.1至1 Mb范围内，间期染色质可被模拟为自由柔性链。两个探针之间的平均平方间期距离与线性DNA分子上探针之间的基因组间隔成正比。在1 - 2 Mb以上，间期距离与基因组间隔之间的关系突然变化，似乎趋于平稳。我们使用碱性硼酸盐处理来扩展间期FISH图谱绘制的能力。我们在此表明，碱性硼酸盐处理会增加细胞核直径、同源染色体上探针之间的间期距离以及同一染色体上探针之间的距离。我们还表明，硼酸盐处理的细胞核中杂交位点之间的平均平方距离与高达4 Mb的基因组间隔成正比。因此，碱性硼酸盐处理通过增加探针之间的绝对距离并扩展间期距离与基因组间隔之间简单关系的范围，增强了间期FISH图谱绘制的能力。
