The effect of DNA sequence on nucleosome binding. Runs of two or more adjacent A=T base pairs facilitate the bending of DNA, whereas runs of two or more G≡C base pairs have the opposite effect. When spaced at about 10 bp intervals, consecutive A=T base pairs help bend DNA into a circle. When consecutive G≡C base pairs are spaced 10 bp apart and offset by 5 bp from runs of A=T base pairs, the DNA binds tightly to the nucleosome.