“…The nucleosome core is a fragile object (van Holde, 1988). Systematic study of the stability of nucleosome cores isolated from the nuclei of somatic cells has determined the temperature, pH, and salt concentrations at which histone-DNA interactions are disrupted (Zama et al, 1978;Gordon et al, 1979;Libertini and Small, 1980;Burch and Martinson, 1980;Burton et al, 1978;Walker and Wolffe, 1984). An important aspect of nucleosome core stability is the sensitivity of histone-DNA interactions to dilution.…”