in particular , the tetramer ( h4-h3 ) - ( h3-h4 ) is in close contact with the central part of the dna , but significant contacts are seen also between the histones h3 and the extremities of the super-helix , thus explaining the stability of a nucleosome-like particle depleted of h2a and h2b .
C0028623
nucleosome
C0019646
h2a