Fig 6.

Model for Brc1 stabilizing replication forks in pericentromeric heterochromatin. Collisions between the replisome and RNA Pol II trigger γH2A formation by Rad3 (not shown), resulting in recruitment of Brc1. Stabilization of the replication fork by Brc1 favors RNAi-mediated disassociation of RNA Pol II from the chromosome, allowing fork restart by the Rik1-associated replisome (22). Loss of Brc1 destabilizes the fork and increases the frequency of HDR-mediated fork restart by a reassembled replisome that is not associated with the Rik1 complex. See the text for additional description.