Denaturation of mouse satellite and ribosomal DNA during hydroxyapatite thermal chromatography of chromatin.

Mouse DNA and chromatin were melted on hydroxyapatite and the denaturation profiles of ribosomal and satellite DNAs were followed by hybridization with their complementary RNAs. Neither ribosomal nor bulk DNA had significantly different melting profiles in chromatin as compared to DNA. However, most of satellite DNA eluted at higher temperature from chromatin than from purified DNA. One explaination for the higher melting temperature of mouse satellite DNA in chromatin suggests that the complex between this particular DNA component and at least some proteins in chromatin is more stable than the average DNA-protein interaction.