Replisome unloading: mechanism and importance for cell biology

Every time a human cell divides, it must copy its entire genome—and the molecular machinery that does the copying must then be dismantled, or the cell risks genetic chaos. Despite six decades of research into DNA replication, scientists still do not understand how this dismantling process works in human cells. The machinery that copies DNA, called the replisome, is a complex of dozens of proteins. If it is not properly disassembled after replication finishes, the consequences can include genetic disease, cancer, and premature ageing. Yet the mechanism of replisome disassembly has never been studied in human cells. This project will be the first to describe how replisome disassembly is accomplished and coordinated in human cells. The researchers will combine biochemical experiments using frog egg extracts with cell biology studies in immortalised human cell lines. They aim to identify new regulators of the process and determine what happens when it goes wrong. This is fundamental science. There is no immediate practical application. But understanding how cells safeguard their genome during every division is essential groundwork. Similar fundamental discoveries about DNA repair and replication have, over decades, directly informed cancer therapies and genetic diagnostics. A deeper grasp of replisome disassembly could eventually open new avenues for targeting diseases driven by genome instability.