FIG. 2.

Distribution of Imp protein in the ovary. (A) Imp is transiently concentrated in an anterodorsal zone flanking the oocyte nucleus on the anterior and lateral sides (arrowheads). This localization can be detected as soon as the nucleus migrates to the anterior of the oocyte and is largely lost by mid-stage 9. (B) Imp is concentrated in a crescent at the posterior pole of the oocyte. (C to E) The anterodorsal concentration of Imp in the oocyte is specific. Egg chambers were double labeled for Imp (C) or Vas (D). Both proteins can be detected throughout the oocyte cytoplasm. In the overlay of the two signals (E), the ratio of green to red is substantially greater in the lateral and anterior sides of the nucleus than elsewhere in the cytoplasm, indicating that Imp is specifically concentrated at these regions of the oocyte.