Delineation of DNA replication time zones by fluorescence in situ hybridization.

摘要: Abstract Fluorescence in situ hybridization has been used to visualize specific genomic DNA sequences interphase nuclei. In normal diploid cells, unreplicated segments give singlet signals while replicated loci are characterized by doublets. The distribution of these two patterns unsynchronized cell populations can be determine the S phase replication time any sequence. validity this approach was established analyzing genes whose profiles expressing and non-expressing cells had determined previously conventional methods. Using technique it possible map timing topography within flanking cystic fibrosis (CF) gene locus on chromosome 7. itself is located a defined zone which approximately 500 kb length under developmental control. It early replicating express CF but late other types. These zones probably represent basic units structure.