Monopolar Aur-B122R oocytes underwent anaphase I and anaphase II. (A, top) Time series (side view) of a representative oocyte injected with wild-type Aur-B (as control), depicting metaphase I (00:04), anaphase I (00:08 and 00:12), and cytokinesis (00:14 and 00:18). See Video 3 for the entire series. The far right image (metaphase II) was from a different oocyte in the same experiment. (A, bottom) Time series (side view) of a representative Aur-B122R mRNA-injected oocyte exhibiting a monopolar spindle (00:14), monopolar anaphase (00:17 and 00:26), and metaphase II with another monopolar spindle (01:06). Cross-sectional views of selective time points are also shown to depict the transient membrane protrusion (00:26, arrows). The schematic depicts the position of the monopolar spindle/chromosomes in live oocyte. See Video 4 for the entire series (n = 9). (B, top) Time series (side view) of a control oocyte undergoing meiosis I, via imaging chromosomes (H2B) and the spindle poles (Alexa Fluor 488 anti–Aur-A). See Video 5 for the entire series (n = 9). (B, bottom) Time series (side view) of a representative monopolar Aur-B122R oocyte, depicting chromosome poleward movement (00:15 and 00:27) followed by the formation of another monopolar (meiosis II) spindle (00:48). See Video 6 for the entire series (n = 13). (C) Karyotype analyses of monopolar Aur-B122R oocytes at metaphase I (top), metaphase II (middle), and 15 min after prick activation (bottom). (D) Monopolar Aur-B122R oocytes were karyotyped between 110 and 145 min after GVBD. The graph summarizes >10 experiments (n = 72).