Fig. 4. Homologous recombination is impaired in TC expressing endothelial cells.

a Representative images showing endothelial cells that were left untreated, incubated with dox for 24 h to induce TC expression, or treated with 30 μM H₂O₂. Cells were stained with DAPI (nuclei; blue), γH2AX (magenta), and BRCA1 (green). b Ratio of mean BRCA1 to γH2AX nuclear fluorescence intensity from imaging experiments shown in (a). c Ratio of the overall percentage of γH2AX to BRCA1 foci positive endothelial cells from imaging experiments as shown in (a). d Representative images showing endothelial cells that were left untreated, incubated with dox for 24 h to induce TC expression, or treated with 30 μM H₂O₂. Cells were stained with DAPI (nuclei; blue), γH2AX (magenta), and RAD51 (green). e Ratio of mean RAD51 to γH2AX nuclear fluorescence intensity from imaging experiments shown in (d). f Ratio of the overall percentage of γH2AX to RAD51 foci positive endothelial cells from imaging experiments as presented in (d). All imaging was performed on a Zeiss fluorescence widefield microscope using a 63x oil immersion objective. Scale bars = 20 μm. A minimum of 150 cells per condition were quantified per experiment, n = 3. Statistical significance was calculated with an unpaired t test in all panels. In all panels error bars show SEM, and *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001.