the nucleosomes released by a brief micrococcal nuclease digestion were fractionated by hgii-affinity chromatography to separate the unfolded nucleosomes of transcriptionally active genes ( in which the sulfhydryl groups of histone h3 are accessible for binding to hgii ) from the compactly beaded nucleosomes of transcriptionally inert dna sequences ( in which the h3 sulfhydryl groups are not accessible ) .
C0019647
histone h3
C0028623
nucleosomes