During DNA replication, topoisomerase proteins (TOPs) play a critical role in making temporary DNA-strand breaks so they can be untangled and made accessible to the replication machinery. Some chemotherapies, such as camptothecin work by trapping TOPs on the DNA, causing sustained breaks and cell death. The TDP1 protein can help repair this damage, but it is not clear what other players may be involved in this process. A new study led by Huimin Zhang, Ph.D.,...