THE CHROMATIN NETWORK - IMAGE-ANALYSIS OF DIFFERENTIATING CHICK-EMBRYO CHONDROCYTES

The chromatin network was revealed in DNA stained cell imprints of dev eloping chick embryo chondrocytes using the recently developed method of TV image processing. The network consists of two classes of alveole s. The large alveoles, which accompany large chromocentres, are concen trated at the centromeric nuclear pole representing the most stable pa rt of the network. The small alveoles, connected with the small chromo centres and located around the chromosome arms and telomeric ends, are dynamic. These smaller alveoles appear in differentiating chondroblas ts and disappear in ageing chondrocytes. Ectopic conjunctions involvin g constitutive and intercalary heterochromatin are responsible for the network formation.