Fig. 7.

A model for functions of Isw2 and Ino80 at stalled replication forks. (a) In the absence of replication stress, the replisome (green rectangle) moves smoothly. Isw2 and Ino80 physically interact with RPA (blue circles) independently of replication stress and DNA. Gray circles denote nucleosomes. (b) When a replication fork encounters replication stress, the fork stalls. RPA then accumulates and targets Isw2, Ino80, and checkpoint proteins. Isw2 and Ino80 at stalled replication forks attenuate the S phase checkpoint response and facilitate the subsequent deactivation process.