Nucleolus segregation is not equal in TbAGO1-/- cells. Immunofluorescence of trypanosomes stained with the anti-nucleolus marker L1C6 monoclonal antibody and counterstained with DAPI to show nuclear and mitochondrial DNA. A. Wild-type trypanosomes, B. TbAGO1-/- trypanosomes. In both cases, the top series shows a phase contrast image superimposed onto the DAPI image (blue), and the bottom series shows the DAPI image (blue) merged with nucleolus staining (red). Left panels, cells at the anaphase stage of nuclear mitosis. Middle and right panels, cells at the telophase stage of nuclear mitosis. In wild-type cells (A), both nuclei inherit similar amounts of nucleolar material, whereas clear differences are visible between the two nuclei in a large number of binucleated cells from the TbAGO1-/- mutant (B).