Missegregation of an ensheathed chromosome results in a micronucleus with a disrupted NE. (A) Confocal images showing examples of an intact or a disrupted micronucleus as indicated. Images show mCherry-BAF or LBR-mCherry (red) stably coexpressed with GFP-Sec61β (green) in RPE-1 cells; H3K27ac was detected by immunofluorescence (blue), and DNA was stained with DAPI. XY view is through the center of the micronucleus; YZ (right) and XZ (below) are orthogonal views at the positions indicated. Scale bar, 10 µm. (B) Scatter plots to show the fluorescence intensity of H3K27ac (blue) and either mCherry-BAF or LBR-mCherry (red) vs. GFP-Sec61β intensity. Data are plotted as the log₂ ratio of intensity at the micronucleus vs. main nucleus. For RPE1 GFP-Sec61β mCherry-BAF, n = 71 cells, and LBR-mCherry, n = 73 cells, from three independent experiments in each cell type.