Histone H3.1 is a chromatin-embedded redox sensor triggered by tumor cells developing adaptive phenotypic plasticity and multidrug resistance

Raw data for panels 5A-D. Py230, Py8119 cells expressing roGFP2-Orp1 and inducible TET-ON NLS-catalase were treated with 200 nM doxorubicin (DXR) or 10 nM paclitaxel (PTX) for 15 days after seeding. The expression of NLS-catalase occurred by treating the cells with 100 ng/mL doxycycline. The redox state of the nucleus and cell death/proliferation were measured daily using the Lionheart FX microscope (Biotek). roGFP2-Orp1 was excited sequentially at 405 nm and 488 nm and the emission was recorded at 525 nm. The generated images were analyzed using FIJI ImageJ. Each channel was converted to 8-bit, and Median (radius = 2 pixels) and Gaussian blur (radius = 2 pixels) were applied. The background was subtracted and a threshold was set to avoid artifacts. Only the nuclear area was considered for the analysis. Oxidation levels were then determined on a pixel by pixel basis using the Imaging Expressing Parser tool. Final values were obtained using Analyzing particles tool (size: 10 μm2 - infinity; circularity: 0.10–1.00).