Histones F2a1 and F3 interact reversibly and cooperatively with DNA to form an equimolar complex in chromatin

The establishment of a reversible thermodynamic equilibrium has an important bearing on the question of salt induced histone rearrangements recently studied. It has been argued on the basis of these results that the structural properties of depleted nucleohistones prepared by salt dissociation bear little relation to the properties of the native chromatin on account of the extensive rearrangements of histones which take place under the effect of the salt. From a structural point of view such rearrangements become unimportant if it can be shown that the histones, DNA and salt are in rapid, reversible equilibrium. This study shows that this is the case for f2a1 and f3.