[Nucleotides of rat liver cells: electron microscope analysis].

Nucleoids of rat hepatocytes have been studied with the aid of electron microscopy. Proceeding from a morphologic comparison of nucleoids obtained at different conditions, it has been inferred that rosette-like structures are the basic element of nuclear DNA loop organization detected by sedimentation and fluorescent methods. Divalent metal ions play a significant role in stabilizing rosette-like structures. A scheme for DNA organization in the somatic cell interphase nucleus is suggested.