FIG. 2.

In situ hybridization to whole-mount embryos and ovaries to visualize the distribution of ZAM transcripts. (A) Schematic representation of an adult ovariole. The ovariole is composed here of the germarium (early stages of oogenesis) and later of two follicles in stages 9 and 10. The germ line cell nuclei (nurse cells and oocyte nuclei) are in grey, and the somatic cell nuclei (follicle cell nuclei) are in black. (B to F) In situ hybridizations of ZAM RNAs with the antisense env riboprobe (Fig. 1); (G) similar experiment with a sense env riboprobe. (B) Late embryos (up to 10 h at 20°C) of the RevI strain. Arrowheads, hybridization signals located in gonads. (C) Ovariole of RevI female. Arrowheads, hybridization signals located in the somatic follicular cells at the posterior part of each follicle and in the germarium. (D) Higher magnification of RevI follicles (stage 10). Strong hybridization signals are observed (arrowheads) in the posterior follicular cells. (E) Late embryo of the w^IR6 strain. After a long time of revelation, a leaky signal is observed in the gonads (arrowheads). (F) Ovariole of the w^IR6 strain. No signal is detected in the follicular cells and the germarium. (G) Negative control of RevI follicle hybridized with the sense env riboprobe. In all panels, the anterior part of an embryo or ovariole is at the left margin.