Figure 2.

Nuclear migration dynamics of diploid cnm67Δ cells. Mitotic cell cycles were observed by in vivo time-lapse fluorescence microscopy. Nuclear positioning of the preanaphase nucleus to the bud neck is usually similar to wild type (e.g., 0′, cell A). Unlike in wild type, spindle elongation during anaphase is mostly restricted to the mother cell (e.g., 18′, cell A). Elongation of the anaphase spindle usually occurs along the mother–bud axis (e.g., 18′, cell A) and is normally followed by a successful nuclear movement into the bud (e.g., 27′ and 42′, cell A). In case of spindle misalignment (192′, cell A), the subsequent nuclear migration often fails (201′–345′, cell A) leading to a binucleate cell with an anucleate bud. Nuclear divisions in binucleated cells occur simultaneously (354′, cell A, and 498′, cell B). After successful transit of a nucleus into the bud, separation can be observed by a change of the position of the bud relative to the mother cell during cytokinesis (e.g., 42′ and 63′, cell A). Anucleate buds (marked with asterisks) are not separated from the mother cell (cell A from 300′ and cell B from 360′). Bar, 10 μm. Movie 2: Nuclear dynamics as seen in Hhf2-GFP–labeled cnm67Δ cells followed for 8 h. Acquisition interval, 1 min; movie speed, 10 frames per second = 10 min/s. One z-axis plane fluorescence image was acquired.