DNA Ligase IV Prevents Replication Fork Stalling and Promotes Cellular Proliferation in Triple Negative Breast Cancer

Figure 4

Lig4 depletion alters basal levels of replication. (a, b) BT549 cells were treated with siRNA targeting either Lig4 or scrambled control (NT) and DNA replication was assessed using the DNA fiber assay. Briefly, cells were sequentially pulsed with thymidine analogs IdU and CldU and the DNA fiber assay was conducted [10]. For each treatment, stalled, new and restarted replication forks were scored after blinding for treatment. Percent of stalled, new and restarted replication forks in Lig4 depleted cells were compared with respective NT control cells (p<0.05).