Mitochondrial fission in asexual blood-stage parasites. Immunofluorescence assay on MitoRed schizonts stained with anti-GAP45 antibody (green) to visualize IMC and DAPI (DNA, blue). The mito-mScarlet signal is shown in magenta. Four different stages of schizont maturity are distinguished: pre-segmentation (pre seg), schizonts still undergo nuclear division (nuclei are large and irregularly shaped) and there is no or very little IMC staining without clear curvature. Early-segmentation (early seg): schizonts have (almost completely) finished nuclear division (nuclei are small and round) and there is a clear IMC signal that has a curved shape at the apical end of the forming merozoites but is less than halfway formed. Mid-segmentation (mid seg): the IMC of the segmenting merozoites in these schizonts is more than halfway formed, but there is still a clear opening at the basal end of the merozoite. Late-segmentation (late seg): in these schizonts the IMC seems to be completely formed with no clear opening at the basal end of the forming merozoites. Images are single slices of a Z-stack taken with an Airyscan confocal microscope. Images of the mito-mScarlet signal in the seventh column are maximum intensity projections (MIPs) (41 slices, 150 nm interval). Images in the eighth column are crops of the GAP45 signal depicted in the first column, indicated by the dotted-line areas. Scale bars, 2 μm; scale bars crops, 1 μm.