The chromosomal localisation of satellite DNA in Ptyas mucosus (Ophidia, Colubridae).

Ptyas mucosus male DNA has a repetitious DNA satellite (p = 1.700 g cm-3) constituting 5% of the haploid genome. In situ hybridisation of radioactive complementary RNA (cRNA) has revealed that satellite sequences are located in the centromeric region of one pair of macrochromosomes and in the terminal region of 8 pairs of microchromosomes. These regions are constitutively heterochromatic as revealed by C-banding. The possibility of involvement of satellite rich microchromosomes in nucleolus organisation is discussed.