Fig 2: CSN subunits localize in distinct structures at the midbody during cytokinesis. (a) Representative images of EGFP-tagged CSN4, CSN5 and CSN6 expression at the midbody, which are identified using differential interference contrast (DIC) (black arrows). Boxed areas represent magnified images in the y/z orientation of the midbody for each fluorescence micrograph shown above in the x/y orientation. (b) Representative midbodies found in the image at the far left (white box) are shown at the right magnified to highlight the expression pattern of CSN subunits in both the x/y and y/z orientation. Double co-localization using transiently expressed EGFP-CSN5 (green), paired with mRuby2-CSN4 or CSN6 (red) at midbodies, as identified with MKLP1 antibody staining (blue). Line scan plots of the signal intensity across the midbody (bounded by opposite-facing arrowheads) are shown for each fluorescent channel. (c) Mean EGFP fluorescent signal intensity of all CSN subunits at midbodies was scored and compared with EGFP alone, with the data represented as vertical scatter plots with mean, SEM. The number of measurements made from individual cells (N), collated from three replicates, are shown below each scatter plot. Significance was determined using an unpaired Student’s t-test with Welch’s correction. ns = not significant, *** = p < 0.001, and ** = p < 0.01.