Fig. 3. Classes of mutants affecting the localisation of oskar mRNA. GFP-Staufen (green) and rhodamine-phalloidin staining (red) are shown in the left panels (A,C,E,G,I,K). oskar in situ hybridisations are shown on the right (B,D,F,H,J,L). (A,B) Wild-type egg chambers. (C,D) vagabond^7A1-3. In this mutant, GFP-Staufen and oskar mRNA fail to localise to the posterior and oskar mRNA accumulates at the anterior of stage 9 oocytes. In C, the oocyte nucleus is also mislocalised to the lateral oocyte cortex (arrow). (E,F) fraenkel^4B2-7, a member of the class of mutants in which GFP-Staufen and oskar mRNA localise ectopically to the centre of the oocyte. (G-J) 2B1-8 egg chambers. In this mutant, GFP-Staufen and oskar mRNA localise to the posterior of the oocyte in stage 9 (G), but fail to be maintained there in later stages (I,J). In the stage 10A oocyte shown in H, oskar mRNA seems to be falling off from the posterior cortex. (K,L) glissade^9E9-3 exemplifies the class of mutants in which GFP-Staufen and oskar mRNA localise to the posterior part of the oocyte, but not in a cortical crescent.