| The central role of chromatin modifying factors in the regulation of gene expression is well established, however little has been reported about how such factors are involved in DNA replication. GCN5 encodes one of the Histone Acetyl-transferases (HATs) genes in S. cerevisiae that functions as a coactivator in transcriptional regulation, and could also be implicated in centromere maintenance. Here I provide evidence that links Gcn5p with the regulation of DNA replication. I show that disruption of GCN5 decreases the stability of mini-chromosomes and that high copy of GCN5, TRA1 and SPT7 suppress the temperature sensitivity (Ts) and mini-chromosome instability phenotypes characteristic of the replication mutants orc2-1, orc5-1 and mcm5-461. Furthermore, I observed physical association between Gcn5p and origins of DNA replication, while its deletion leads to increased chromatin condensation at an origin of replication. |
