Chromosomal DNA synthesis begins at origins of replication, with some origins activating earlier than others during S-phase. Neither the mechanism by which origin activation time is determined nor the biological significance of this temporal program is fully understood. Interestingly centromeres, sites where kinetochore complexes form to correctly separate chromosomes during mitosis, replicate early. In the budding yeast Saccharomyces cerevisiae, centromeres actively promote their own early replication by advancing the activation time of their neighboring origins. We previously showed, in cells lacking the mitotic checkpoint, an artificially delayed, late replicating centromere causes a dramatic increase in chromosome instability. In this study, I am investigating the function of centromere-like regions (CLRs) in S. cerevisiae. These sequences can bind the centromeric histone (Cse4), especially when CSE4 is overexpressed. Under this condition, additional kinetochore proteins can build up and CLRs take on some of the properties of functional centromeres. Because the kinetochore protein Ctf19 recruits a replication initiation factor, I hypothesize that the centromere-mimicking DNA sequences are also capable of recruiting the kinetochore protein associated with early replication to advance the initiation time of nearby origins. To test this possibility, I will examine the effects of the CLR on replication origin activation using a plasmid that contains two identical origins. I will clone a CLR next to one of the origins and determine whether this origin is now the earlier activated origin on the plasmid when CSE4 is overexpressed. The CLR I will use resides in an early replicating part of the yeast genome. In a complementary experiment I will delete the genomic copy of this CLR and measure its effect on firing time of the adjacent origins. The results of this study will provide us deeper insights on how cells orchestrate when and where in their genome to start duplication.