Figure 3.

Effects of the presence of centromeric nucleosomes (in red) in the loop extrusion process. (A) Blocking and anchoring effects. In both, one centromeric nucleosome blocks the motion in its direction, but the opposite side of the LE (in yellow) continues to reel. In the blocking effect the LE interacting with the centromeric nucleosome can unbind, but in the anchoring effect the LE is permanently bound to the centromeric nucleosome. (B) For comparison, centromeric nucleosomes that do not interact with the LE can pass through it.