Fig. 2
asf1 KD does not affect oogenesis but frequently impairs meiotic divisions. a Stage 9 egg chambers from control w1118 (left) and asf1 KD (right) ovaries stained for ASF1 (green) and DNA (red). In control egg chambers, ASF1 accumulates in the germinal vesicle (arrows; n = 30). In ovaries expressing the asf1 shRNA in germ cells, ASF1 is still weakly detected in the oocyte nucleus (arrows) at the same stage (n = 14). Scale bar: 20 μm. n indicates the number of egg chambers analyzed. b A stage 9 egg chamber expressing V5-tagged ASF1 protein (green) from a genomic asf1-V5 transgene (g-asf1::V5). The ASF1::V5 protein accumulates in the germinal vesicle (arrow) but is also enriched in nurse cell nuclei (arrowhead) positive for the replication factor PCNA (red; n = 12). DNA is in blue. Scale bar: 20 μm. Color panels in a and b show merged stainings. c Chromosomal defects are frequently observed during the second meiotic division in asf1 KD eggs. The meiosis in the left panel appears normal but the one on the right shows a lagging chromosome (arrowhead) and a chromatin bridge (arrow). The chromatin bridge is more visible in the inset where the contrast has been intentionally increased. Scale bar: 20 μm. d Quantification of abnormal female meiotic divisions in asf1 KD eggs