Distribution of non-histone proteins between micrococcal nuclease sensitive and nuclease resistant chromatin from chicken cells with active and inactive genomes.

Chicken liver and erythrocyte nuclei were separated by mild treatment with micrococcal nuclease into nuclease sensitive (NS) and nuclease resistant (NR) fractions, differing in chemical composition and transcriptional activity in vitro. Nuclei, NS and NR fractions of both tissues were fractionated by hydroxyapatite chromatography into three groups of non-histone chromatin proteins (NHCP) and characterized by SDS-polyacrylamide gel electrophoresis. Some differences in the molecular distribution of non-histone proteins of chicken liver and erythrocytes between nuclease sensitive and resistant parts of chromatin have been described.