The histone chaperone CAF-1 prevents homologous recombination-mediated instability of the budding yeast ribosomal DNA during replication-coupled DNA double-strand break repair.

ABSTRACT: DNA replication-coupled chromatin assembly is crucial to maintain genome integrity. Here, we demonstrate that the absence of the budding yeast histone chaperone CAF-1 induces the production of extrachromosomal ribosomal RNA gene (rDNA) circles (ERCs), accompanied by chromosomal rDNA copy number changes, in a manner dependent on Fob1-mediated DNA replication fork arrest in the rDNA, the homologous recombination (HR) protein Rad52, and its interaction with proliferating cell nuclear antigen. In the caf-1 mutant, ERC production is triggered partly by increased transcription from the regulatory promoter E-pro, but is also affected by defects independent of E-pro misregulation. Absence of CAF-1 accumulates resected DNA double-strand breaks (DSBs) formed at arrested replication forks, repair of

SUBMITTER: Futami H 

PROVIDER: S-EPMC12657057 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature