Fig. 1. endos⁰⁰⁰⁰³ oocytes fail to undergo meiotic maturation. (A) DAPI-stained egg chambers in different stages. nc, nurse cells; oo, oocyte; da, dorsal appendages. Asterisks indicate position of the oocyte nucleus. Scale bar: 100 µm. (B-F) Control oocytes in prophase I (B-D) and in metaphase I (E,F). Arrows indicate non-exchange fourth chromosomes. (G-K) endos⁰⁰⁰⁰³ oocytes have a prolonged prophase I (G-J) and abnormal DNA morphology at stage 14 (K). (L-P) twine¹ oocytes show similar phenotypes to endos⁰⁰⁰⁰³ oocytes. (Q-U) elgi¹ oocytes in prophase I (Q,R) and in premature metaphase I (S-U). Scale bar: 5 µm. Control (F') and elgi¹ (U') have dehydrated stage 14 oocytes. endos⁰⁰⁰⁰³ (K') and twine¹ (P') oocytes are not dehydrated and have abnormal yolk morphology. Scale bar: 100 µm. (V) Quantification of DNA morphology. The number of oocytes analyzed is shown above the bars. ^*P<0.001.