[Effect of heparin polyanion on chromatin preparations obtained in solutions of low ionic strength]

DNP obtained in low ionic strength solutions (0.7 mM Na-phosphate buffer, pH 7.0) was found to be dissociated under the effect of heparin. The dissociation order of the three histone fractions was established: H2a, H1, H4. The following order of histones is assumed: H2a, H2b, H1, H3, H4. Activation of the DNA and RNA synthesis in the eucaryotic cells, their nuclei and chromatin under the effect of low heparin doses should be associated not with the H1 histone dissociation, but with the dissociation of histones moderately rich in lysine--H2a, and, probably, H2b.