Fig. 5.

Models for regulation of cohesion by sororin and Eco2 cohesin (green clamps) associates with chromatin (blue) before DNA replication. DNA replication either promotes activation of the Eco2 acetyltransferase (orange) directly, causing it to modify the cohesin complex, or causes a change in the cohesin complex (indicated as opening of the complex), which makes it a good Eco2 substrate. Once the cohesin complex is modified by Eco2 it can be bound by sororin (yellow) (A). Eco2 added after DNA replication is able to bind chromatin, but unable to modify cohesin and generate the sororin-binding site (B).