Z4 proteins co-localize with and are sequestered by BRD4-NUT. A, Immunofluorescence of TC-797 cells using anti-NUT and anti-ZNF592 antibodies. (magnification: 1000×, scale bar = 10 μm.) B, Immunofluorescence of 797TRex cells with (+) or without (–) tetracycline induction of FLAG-BRD4-NUT-HA expression using anti-HA (visualizing FLAG-BRD4-NUT-HA), anti-ZNF532, anti-ZNF592 and anti-ZMYND8 antibodies. (magnification:1000×, scale bar = 10 μm.) C, Top: Immunofluorescence of U2OSTRex cells with (+) or without (–) tetracycline induction of FLAG-BRD4-NUT expression using anti-NUT, anti-ZNF592 and anti-ZMYND8 antibodies. (magnification:1000×, scale bar = 10 μm.) Bottom: Boxplots showing the number of foci formed by ZNF592 (left) or ZMYND8 (right) in U2OSTRex-FLAG-BRD4-NUT cells treated with ethanol vs. tetracycline. FLAG-BRD4-NUT expression was induced by tetracycline treatment for 36 hours. Up to 40 nuclei were counted. *p<0.01, Student’s t test.