[DNA from chromatin-nuclear membrane complex: reassociation kinetics at different stages of the cell cycle]

Base composition and reassociation kinetics of DNA from chromatin-nuclear membrane complex of rat liver cells at different stages of the cell cycle. The complex isolated in low ionic strength solutions contains about 9% of total nuclear DNA, and its density in sucrose solution is 1.27 g/cm2. DNA, isolated from the complex, is homogenous in its molecular weight (approximately 2-10(6) daltons) and is similar in its base composition to total nuclear DNA. However, DNAs from complexes, isolated at interphase and different S-phases of the cell cycle, differ from total nuclear DNA in reassociation kinetics: DNAs from complexes are enriched by approximately 10% with unique nucleotide sequences. It is concluded from the similarity of reassociation kinetics, that molecular population of nuclear membrane-bound DNA does not change considerably throughout the cell cycle.