Open AccessChemical and physical properties of fractionated chromatin.
Author(s) -
Ellen M. Berkowitz,
Paul Doty
Publication year - 1975
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.72.9.3328
Subject(s) - chromatin , rna , fraction (chemistry) , dna , histone , biology , biochemistry , microbiology and biotechnology , chemistry , chromatography , gene
Sonicated chicken reticulocyte chromatin was fractionated into transcriptionally active and transcriptionally repressed components. The active fraction is 8% of the whole chromatin but contains 70% of the newly synthesized chromosomal RNA. This RNA has five times as many hemoglobin RNA sequences as does the RNA in the repressed fraction. The amount of the active fraction in the chromatins of several tissues correlates with their synthetic activity. The molecular weight of the DNA of the repressed fraction is approximately twice that of the active fraction. Moreover, the configuration of repressed chromatin is much more compact, consistent with a much larger sedimentation constant. The transcriptionally active fraction displays a 6 degrees lower melting profile and is highly susceptible to DNase I relative to the repressed fraction. The active fraction contains twice as much non-histone protein and 15% less histone than the repressed fraction and is lacking the lysine-rich and much of the arginine-rich histones.