Dual functional regulators coordinate DNA replication and gene expression in proliferating cells.

Gene products for cell growth must meet the pace of DNA replication and vice versa during the cell division cycle, therefore coordination of DNA replication and gene expression is vital to proliferating cells. During development in multicellular organisms when rapid cell divisions must be accompanied by the expression of particular gene sets in differentiating tissues, this coordination is even more crucial. Undoubtedly, multiple strategies are used to ensure the coordination of gene expression and DNA replication.

Mcm1 promotes replication initiation by binding specific elements at replication origins.

Minichromosome maintenance protein 1 (Mcm1) is required for efficient replication of autonomously replicating sequence (ARS)-containing plasmids in yeast cells. Reduced DNA binding activity in the Mcm1-1 mutant protein (P97L) results in selective initiation of a subset of replication origins and causes instability of ARS-containing plasmids. This plasmid instability in the mcm1-1 mutant can be overcome for a subset of ARSs by the inclusion of flanking sequences.

Mcm1 binds replication origins.

Mcm1 is an essential protein required for the efficient replication of minichromosomes and the transcriptional regulation of early cell cycle genes in Saccharomyces cerevisiae. In this study, we report that Mcm1 is an abundant protein that associates globally with chromatin in a punctate pattern. We show that Mcm1 is localized at replication origins and plays an important role in the initiation of DNA synthesis at a chromosomal replication origin in vivo.