Figure 3.

TUM is required for proper localization of Subito to the central spindle and chromosome segregation during meiosis I. (A) Protocol used to induce RNAi expression late in oogenesis to bypass the early requirement of TUM in oocyte development. The heat-shock treatment caused some mild karyosome defects in the controls. However, these were occasionally observed in wild type, and the mutant defects were qualitatively different because they involved spindle organization defects not observed in the controls. (B–E) Wild-type and tum RNAi females were heat-shocked and examined for central spindle components. DNA is shown in blue, tubulin in green, and Subito in red in merged images. (B) Subito localizes to the central spindle region in wild type. (C–E) tum RNAi oocytes showing diffuse Subito staining all along the length of the spindle (C); frayed spindles are in D, and monopolar spindles are in E. (F) Wild-type and tum RNAi oocytes showing FISH probes AACAC (chromosome 2) in red and Dodeca (chromosome 3) in white. (G) Summary of mono-orientation frequency in tum RNAi oocytes compared to wild type. Asterisk indicates significantly different values. P-values are calculated by Fisher’s exact test (Table 3). Bars, 5 µm.