Fig. 6.

Embryos from matings with transgenic D. melanogaster males expressing the cinA–cinB^wPip operon show CI-like cytology similar to wNo-infected D. simulans. (A–E) Representative images of propidium iodide-stained embryos from incompatible crosses between wNo-infected males and uninfected females showing (A) an unfertilized embryo, (B) a normal embryo after 1 h of development, (C) a normal embryo after 2 h of development, (D) an embryo with early mitotic failure, and (E) an embryo showing anaphase chromatin bridging. (F) Quantification of embryo cytology. wNo (−) and wNo (+) represent D. simulans-uninfected or infected by wNo, respectively. wNo infection was confirmed by PCR amplification of the cinB^wNo gene (SI Appendix, Fig. S6). For the transgenic D. melanogaster crosses (Bottom), only the cinA-T2A-cinB crosses under the MTD-Gal4 driver (highlighted in red; the NGT-Gal4 driver is highlighted in orange) strongly phenocopied the natural CI cytology. The number of embryos examined in each cross is shown. Embryos exhibiting normal cytology after 1 to 2 h were grouped together and are shown in teal. ****P < 0.0001 by χ² test comparing normal (B and C) and abnormal (A, D, and E) cytological phenotypes.