[Study of acid soluble proteins of metaphase chromosomes isolated from KB cells before and after 5-BrdU incorporation].

Metaphase chromosomes and interphase nuclei have been isolated by two different procedures, using either acidic or alkaline media. The morphological integrity of the isolated material has been monitored by electron microscopy. In the acidic procedure the thickness of the chromosome fibers is reduced but the chromosome gross structure is preserved. However, electrophoretic analysis indicates complete disappearance of histones H1 and partial loss of H2A and H2B. No significant modification of acid-soluble proteins isolated from chromosomes or nuclei was observed after 5-BrdU incorporation for 72 hours.