Studies on ColE1-plasmid DNA and its interactions with histones: sedimentation velocity studies of monodisperse complexes reconstituted with calf-thymus histones
- 1 January 1977
- journal article
- Published by Oxford University Press (OUP) in Nucleic Acids Research
- Vol. 4 (5), 1207-1224
- https://doi.org/10.1093/nar/4.5.1207
Abstract
Complexes between the four calf-thymus histones (H2A, H2B, H3 and H4) and colE1-plasmid DNA have been reconstituted using the procedure of Oudet et al. ((1975), Cell 4, 281-300). The sedimentation rates of the complexes formed were studied under a variety of conditions. In 0.4 MNaCL, 0.1 M Tris pH 7.50, 0.01 M EDTA and 0.02 M NaHSO3, the final dialy-sis-solvent in the reconstitution procedure, the sedimentation coefficients s23 were found to increase when the complexes were reconstituted at increasing histone to DNA ratios. True plateau regions were reached in the case of the relaxed circular and linear forms of the plasmid DNA. The sedimenting boundaries observed for the complexes at saturation are sharp, reflecting a narrow distribution of sedimentation coefficients and a homogeneity of the complex comparable to that of the uncomplexed DNA. Studies of the dependence of s 23 on the concentration of the complex at constant DNA to histones ratio have been undertaken at salt concentrations between 0.4 and 1.5 M NaCL in the above solvent. The formation of the complexes is reversible, at least at the higher ionic strengths. At salt concentrations below 0.36 M the complex precipitates from solution. Omission of histone H4 from the reconstitution mixture abolishes complex formation.Keywords
This publication has 23 references indexed in Scilit:
- Relaxation of chromatin structure by ethidium bromide binding: determined by viscometry and histone dissociation studiesBiochemistry, 1976
- Chromatin structure as probed by nucleases and proteases: Evidence for the central role of hitones H3 and H4Cell, 1976
- Nucleosome formation abolishes base-specific binding of histonesNature, 1975
- Folding of the DNA double helix in chromatin-like structures from simian virus 40.Proceedings of the National Academy of Sciences, 1975
- Preparation of ChromatinEuropean Journal of Biochemistry, 1974
- Chromatin Structure: A Repeating Unit of Histones and DNAScience, 1974
- Purification of the five main calf thymus histone fractions by gel exclusion chromatographyFEBS Letters, 1973
- Chromatin sub-structure. The digestion of chromatin DNA at regularly spaced sites by a nuclear deoxyribonucleaseBiochemical and Biophysical Research Communications, 1973
- The molecular structure of nucleohistone (DNH)Experimental Cell Research, 1970
- Ultracentrifugal analysis of dilute solutionsBiochimica et Biophysica Acta, 1957