Genome. 1993 Apr;36(2):310-6. doi: 10.1139/g93-043.
We have localized the major ribosomal DNA (rDNA) loci on metaphase chromosomes and in interphase nuclei of white spruce (2n = 24) by fluorescence in situ hybridization. Hybridization sites of the biotin-labelled rDNA probe were detected using antibody-fluorochrome conjugates and a confocal laser scanning microscope. White spruce has at least 12, and possibly as many as 14, rDNA sites, 1 site present on each of seven separate chromosome pairs. This is one of the highest numbers of rDNA loci yet reported among plant species. The position of the rDNA loci together with secondary constriction patterns permit, for the first time, all homologous pairs of white spruce chromosomes to be distinguished. We discuss the application of molecular cytogenetics in studies relating to the organization and evolution of DNA sequences within conifer genomes.
我们通过荧光原位杂交技术将主要核糖体 DNA(rDNA) 基因座定位到了白松（2n=24）的中期染色体和间期核上。生物素标记的 rDNA 探针的杂交位点使用抗体-荧光染料缀合物和共聚焦激光扫描显微镜进行检测。白松至少有 12 个，也可能有多达 14 个 rDNA 位点，每个单独的 7 对染色体上都有 1 个位点。这是迄今为止在植物物种中报道的 rDNA 基因座数量最多的之一。rDNA 基因座的位置和二级缢痕模式使得白松染色体的所有同源对第一次能够被区分开来。我们讨论了分子细胞遗传学在与 DNA 序列在针叶树基因组中的组织和进化有关的研究中的应用。
