Three-dimensional reconstruction of pericentromeric (1q12) DNA and ribosomal RNA sequences in HL60 cells after double-target in situ hybridization and confocal microscopy.

A fluorescent in situ hybridization procedure was applied to simultaneously label intranuclear pericentromeric (1q12) sequences of the chromosomes 1 and cytoplasmic ribosomal RNA sequences in whole cells of the promyelocytic HL60 cell line. For this purpose biotinated chromosome 1-specific (1q12) repetitive satellite DNA and 28S ribosomal ssRNA probes were used. The entire procedure was performed in suspension to preserve nuclear morphology. The result was studied by three-dimensional analysis, as provided by a scanning laser confocal microscope. The intracellular positions of both cytoplasmic rRNA and intranuclear centromere 1 DNA could easily be distinguished. This approach could be useful as a framework for the study of the 3-D localization of genes and gene transcripts.