Fig. 2: Nondisjunction of centromere-active B chromosomes results in the formation of micronuclei.
a Anaphase with lagging Bs after immunostaining of CENH3 (in purple) and α-tubulin (in green), for further details see Supplementary Movie 1. Scale bar, 5 µm. FISH signals of the B-specific probes AesTR-183 and AesTR-205 are shown in yellow. Scale bar, 10 µm. The enlarged regions (b, c) are marked by rectangles. Interaction of α-tubulin with the CENH3-positive centromeres of (b) A- and (c) B chromosomes. Scale bar, 1 µm. In total 7 anaphase cells with lagging B chromosomes were analyzed in 3 embryos using super resolution microscopy. On 5 from those cells interaction of α-tubulin with the CENH3-positive centromeres was consistently observed. d Formation of B-containing micronuclei during telophase. Note the position of centromeres on the opposite sides of the micronuclei resulting from the spindle microtubule tension during anaphase. The centromeric signals were observed for 60 micronuclei in 10 embryos. Scale bar, 10 µm. e Box plot showing CENH3 signal volumes (Y-axis, µm3) on A- and B centromeres at anaphase. Measurements are performed for 7 anaphase cells and data are statistically treated. Because the data failed the normality test, a Mann–Whitney test for comparison of both centromere types was performed. The data were not significantly different (P = 0.363). The box indicates the 25th–75th percentiles, the line marks the median. The error bars indicate the 10th and 90th percentiles and the open circles the outlying points. Source data underlying e are provided as a Source data file.
