Detection of nucleolar organizer regions on chromosomes by flourescence in situ hybridization with human 28S rRNA gene and cloning of 28S rRNA gene in Sika deer

The number and loci of nucleolar organizer regions (NOR) on chromosomes in Sika deer (Cervus nippon centralis) were determined by fluorescence in situ hybridization with a human 28S ribosomal RNA (rRNA) gene as a probe. Sika deer that live in Nikko National Park and its neighboring areas (Asio and Seta) in Japan were used. All of the analyzed metaphases had three or four NOR at the end of the first and second longest telocentric autosomes. Nucleolar organizer region association, which is associated specifically on parts of NOR between chromosomes, was also observed clearly. A Sika deer 28S rRNA gene was produced by a polymerase chain reaction method. The nucleotide sequence of a Sika deer 28S rRNA gene determined by an automatic sequencer was 97 bp, and showed homogeneity of 88% for the human sequence.