Figure 7.

Nuf2-RNAi leads to misaligned chromosomes, precocious polar body extrusion, and aneuploidy. (A) Levels of Nuf2 mRNA in siRNA injected oocytes. GV stage oocytes were microinjected with negative control siRNA or Nuf2 siRNA and incubated for 24 h in M2 medium containing 2.5 μM milrinone before collecting the oocytes for real time quantitative PCR. (B) Rates of fist polar body extrusion in siRNA-injected oocytes cultured for various times after release from milrinone. Data are expressed as mean ± SEM of at least 3 independent experiments. *Significantly different (P < 0.05). (C) Spindle morphology and chromosome alignments in MII oocytes after microinjection of Nuf2 siRNA. In the control group, most oocytes showed normal chromosome alignment, while in the siRNA injection oocytes, most oocytes showed slight or severely misaligned chromosomes and different kinds of morphologically defective spindles. α-tubulin (green); DNA (blue). Scale bars: 10 µm. (D and E) The rates of oocytes with abnormal spindles or misaligned chromosomes in the siRNA injection and control group. Data are expressed as mean ± SEM of at least 3 independent experiments. *Significantly different (P < 0.05). (F and G) Chromosome spreading was performed in control and RNAi oocytes. The numbers of univalents in the oocytes in E a; b are 20; 16, respectively. Scale bars: 10 µm.