Figure 8.
Time-lapse imaging of YFP-SUMO chimeras during mitosis. Mitotic divisions of transgenic cells were recorded every 3 min after beginning of cell membrane constriction at late anaphase (designated as 0 min). Single metaphase pictures were taken not to induce artifacts or bleaching of signal while laser scanning. Upper right corner of metaphase pictures shows the time of capture before the start of cytokinesis. Insets at A and C show fixed metaphase cells, also stained with the DNA dye DAPI. YFP-SUMO-1 (A) differed from YFP-SUMO-2 (C) and SUMO-3 (E) with enhanced spindle signal and a distinct perinuclear enrichment. Nonconjugatable YFP-tagged SUMO1 (G) showed only a diffused cytoplasmic signal excluded from the chromosomal area at metaphase and anaphase. B, D, F, and H show corresponding DIC pictures of mitotic cells. Bars, 10 μm.