Frontier Research Institute for Interdisciplinary Sciences
Tohoku University

During each cell division, genomic information must be efficiently replicated and subsequently segregated at mitosis. However, the process of replication is not without incident - it is well established that the replication machinery encounters various obstacles and is designed to have a degree of flexibility, allowing cells to tolerate the problem within limited time during S phase. There are more than 10 DNA polymerases encoded in eukaryotic cells and two polymerase (Polδ and Polε) replicate the bulk of parental DNA. On the other hand, some of other polymerases are less processive but tolerant replication blockage. However, we know little about how activities of DNA polymerases are coordinated during genome replication. We principally tackle this issue in fission yeast; the sophisticated genetics available in this model organism allows careful characterization of various DNA polymerases and how they confer flexibility in DNA replication is examined at a genome-wide level.

Failure in the process of DNA replication leads to genetic changes in daughter cells and potentially causes cancer predisposition in our body. Mutations were frequently found in polymerase genes in cancer cells, implicating that variation in function of DNA polymerase(s) contributes to the development of cancer. Therefore we also characterise properties of DNA replication in cancer cells and then try to develop new insights about potential causes, treatments and biomarkers of cancer.