Conte R A, Verma R S
Division of Genetics, Long Island College Hospital-SUNY Health Science Center at Brooklyn 11201.
Histochemistry. 1994 Dec;102(6):433-5. doi: 10.1007/BF00269574.
Numerous selective and differential staining techniques have been used to investigate the hierarchical organisation of the human genome. This investigation demonstrates the unique characteristics that are produced on fixed human chromosomes when sequential procedures involving restriction endonuclease TaqI. distamycin A (DA) and 4',6-diamidino-2-phenylindole (DAPI) are employed. TaqI produces extensive gaps in the heterochromatic regions associated with satellite II and III DNAs of human chromosomes 1, 9, 15, 16 and Y. DA/DAPI selectively highlights, as brightly fluorescent C-bands, the heterochromatin associated with the alpha, beta, satellite II and III DNAs of these chromosomes. When DA and DAPI are used on chromosomes before TaqI digestion, and then stained with Giemsa, the centromeric regions appear to be more resistant, producing a distinct C-banding pattern and gaps in the heterochromatin regions. Sequential use of the DA/DAPI technique after TaqI treatment produces a bright fluorescence on the remaining pericentromeric regions of chromosomes 1, 9, 16 and Y, which also displayed a cytochemically unique banding pattern. This approach has produced specific enhanced chromosomal bands, which may serve as tools to characterize genomic heterochromatin at a fundamental level.
众多选择性和差异性染色技术已被用于研究人类基因组的层次结构。本研究展示了在固定的人类染色体上，当采用涉及限制性内切酶TaqI、放线菌素A（DA）和4',6-二脒基-2-苯基吲哚（DAPI）的连续程序时所产生的独特特征。TaqI在与人类1、9、15、16号染色体和Y染色体的卫星II和III DNA相关的异染色质区域产生大量间隙。DA/DAPI选择性地将与这些染色体的α、β、卫星II和III DNA相关的异染色质作为明亮荧光C带突出显示。当在TaqI消化之前将DA和DAPI用于染色体，然后用吉姆萨染色时，着丝粒区域似乎更具抗性，在异染色质区域产生独特的C带模式和间隙。在TaqI处理后依次使用DA/DAPI技术，在1、9、16号染色体和Y染色体的剩余着丝粒周围区域产生明亮荧光，这些区域也显示出细胞化学上独特的带型模式。这种方法产生了特定的增强染色体带，可作为在基本水平上表征基因组异染色质的工具。
