The Greene lab investigates how a cell’s DNA repair machinery corrects errors made during DNA replication. When cells copy their chromosomes, replication machinery occasionally makes mistakes. Most of these errors are fixed by a system that removes the faulty nucleotide and replaces it with the correct one, but if missed by the repair machinery the errors can cause diseases such as cancer. Combining biochemical, molecular biology and cell biological methods with a state-of-the-art microscopic technique developed in Dr. Greene’s lab, I will track the movement of repair proteins to see whether they follow on the heels of the replication machinery and whether the replication halts while mistakes are corrected. These findings could provide insights into the biology of cancers that are associated with a failure of this corrective system.