Tightly-bound non-histone proteins in different nucleosome-like subpopulations from pig kidney chromatin.
By differential sucrose gradient centrifugation of pig kidney chromatin in the presence or absence of Na-EDTA and under varying ionic strength conditions, three nucleosome-like subpopulations with different buoyant densities can be obtained. These particles, on the basis of their histones and HMG protein pattern, of the 5-methylcytosine level of their DNA and of the RNA polymerase activity associated with them, can be considered as originating from chromatin fractions differently involved in gene expression. Two-dimensional electrophoresis of the tightly-bound non-histone proteins shows a distinct pattern for each subpopulation, such protein components being notably present in restricted numbers but in high amounts in the subpopulation which was apparently derived from condensed heterochromatin.
Caiafa
P
P
Dipartimenti di Biopatologia Umana e di Scienze Biochimiche, Università di Roma La Sapienza, Italy.
Tomassetti
A
A
Mastrantonio
S
S
Reale
A
A
Spinelli
M
M
Strom
R
R
D000818:Animals; D002499:Centrifugation, Density Gradient; D002843:Chromatin / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D004247:DNA / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D066298:In Vitro Techniques; D007668:Kidney / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism*; D013552:Swine
D002843:Chromatin; D002868:Chromosomal Proteins, Non-Histone; D009707:Nucleosomes; D004247:DNA