A mitotic bookmark coordinates transcription and replication in Drosophila embryos.

ABSTRACT: Collisions between advancing replication forks and elongating transcripts pose a universal threat. During the rapid nuclear division cycles in early Drosophila embryos, coordinating transcription and replication is critical to reduce the risk of collisions. In each cycle, replication begins immediately after mitosis, while transcription starts 3 min later, overlapping replication for the remainder of interphase. We previously showed that transcription depends on Brd4, which forms hubs at active genes. Here, we show that Brd4 persists on mitotic chromosomes as bookmarks of transcriptional activation. Upon anaphase entry, the replication initiation factor Cdc7 forms Brd4-dependent foci that promote early replication in the following interphase. Additionally, Cdc7 activity disperses Brd4 such

SUBMITTER: Cho CY 

PROVIDER: S-EPMC12754778 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature