A.Experimental procedure. I-Cre was induced during 2nd larval instar papillar endocycles. Following endocycles (3rd larval instar), fancd2 RNAi was induced. On pupal Day 2 (D2), the first papillar mitosis was examined. B.EdU labeling (green, DNA in purple), showing S-phase in the 2nd instar larval rectum (area to right of white line). C.EdU/DNA labeling as in B, now showing endocycles are complete in the rectum by 3rd instar stage (note-endocycles continue in the ileum, left of the white line). D.Time-lapse of I-Cre/fancd2 RNAi#1 animal cultured under conditions shown in A. Example unaligned acentric DNA fragment (white arrow) that ends up in a micronucleus following cytokinesis (yellow arrow). Purple-kinetochores (KTs, CenpC Tomato) green-DNA (DNA, his GFP) and cell membranes (Memb, Moesin GFP). Time in minutes relative to anaphase onset. E.Graph of incidence of unaligned metaphase acentric DNA and micronuclei after anaphase in WT or fancd2 RNAi#1 following I-Cre expression, as in panel A. From N= 30-32 cells/condition. *=significant change by Chi-squared, p<.001. White scale bar=25 μm, Yellow scale bar=5μm.