Proteome

DNA replication factor CDT1

Proliferating cell nuclear antigen

Origin of replication

Biology

Control of chromosome duplication

Minichromosome maintenance

Replisome

Origin recognition complex

Replication factor C

Pre-replication complex

Computational biology

DNA replication

Cell biology

Genetics

Chromatin

Eukaryotic DNA replication

Cell Reports

Identifying proteins that function at replication forks is essential to understanding DNA replication, chromatin assembly, and replication-coupled DNA repair mechanisms. Combining quantitative mass spectrometry in multiple cell types with stringent statistical cutoffs, we generated a high-confidence catalog of 593 proteins that are enriched at replication forks and nascent chromatin. Loss-of-function genetic analyses indicate that 85% yield phenotypes that are consistent with activities in DNA and chromatin replication or already have described functions in these processes. We illustrate the value of this resource by identifying activities of the BET family proteins BRD2, BRD3, and BRD4 in controlling DNA replication. These proteins use their extra-terminal domains to bind and inhibit the ATAD5 complex and thereby control the amount of PCNA on chromatin.

Functional Analysis of the Replication Fork Proteome Identifies BET Proteins as PCNA Regulators