Fig. 7. Oocyte chromosomes do not maintain a diakinetic arrangement upon WEE-1.3 depletion. (A-F) Wild-type (A,B), WEE-1.3-depleted (C-E), and emo-1 (F) animals were DAPI stained to visualize oocyte chromosomes. Arrows and white boxes mark the normal diakinetic arrangement of chromosomes in growing oocytes; those marked with a white box are enlarged in B,D. White lines mark the spermatheca and the highly condensed sperm chromosomes. Carets (^) in C mark the most proximal oocyte chromosomes that have coalesced. (E) The -3 oocyte has stringy chromosomes and is flanked by normal diakinetic oocytes to the right and oocytes with coalesced chromosomes to the left. Asterisk in F marks an endoreplicating oocyte. (G-M) Images of live, untreated (G-J) or WEE-1.3-depleted (K-M) histone H2B::GFP transgenic animals. Diakinetic chromosomes are apparent in wild-type (G-I) and WEE-1.3-depleted (K) animals, and are marked with arrows and white boxes; the one in the white box in G is enlarged in H. The chromosomes of a wild-type fertilized oocyte congress during metaphase I (marked by a circle in I and enlarged in J). The coalesced chromosomes of WEE-1.3-depleted oocytes are marked by white arrowheads (K) and one is enlarged in L. (M) The uterus of a WEE-1.3-depleted animal in which the oocyte chromosomes have begun to endoreplicate. ut, uterus; spth, spermatheca. Scale bars: in A, 20 µm for A,C,F,G,I,K,M; in B, 5 µm for B,D,H,J,L; in E, 5 µm.