Fig. 1. Defects in Orb and Grk expression in late stage orb^mel egg chambers. Ovaries from wild-type and orb^mel females were stained with antibodies against Orb protein (panels on left) and Grk protein (panels on right). The genotypes of the ovaries are as indicated. In wild-type stage 9 egg chambers (top panels), Orb protein accumulates at high levels in the cortical cytoplasm around the entire circumference of the oocyte. Grk protein is localized in a cap above the oocyte nucleus in the anterior corner of the oocyte. Note that the Grk antibody gives `nonspecific' background staining in nurse cells and follicle cells. This background staining is observed grk null chambers (not shown). Representative orb^mel chambers are shown in the three lower panels. In the first of the group of orb^mel chambers, the level of Orb protein appears reduced in most of the oocyte except at sites near the posterior pole. Little or no Grk protein is detected. In the panels in the middle, only low levels of Orb protein are observed, while there appears to be a small amount of Grk protein along anterior margin of the oocyte near the oocyte nucleus. The lower panel shows a stage 10 egg chamber with little or no Orb or Grk protein.

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