Figure 6

Expression of Amvasa in Honeybee ovaries. Scale bars represent 100 micrometers. A) The full length of a mated queen ovariole stained for Amvasa RNA. Amvasa RNA is present in both nurse cells and oocytes but not follicle cells. Staining is absent from the oldest oocytes, an artefact caused by problems getting labelled probes into these oocytes. All other oocytes have uniform staining of Amvasa RNA except those in the germarium and terminal filament where Amvasa RNA is absent. Amvasa RNA is also present in the nurse cells. In the early vitellarium, the nurse cells closest to the oocyte express lower levels of Amvasa RNA (arrows), but this difference in expression is not seen in the late vitellarium. Amvasa RNA levels are reduced in the last set of nurse cells, which are degrading prior to fertilisation and oviposition of the egg. B) Amvasa RNA expression in the vitellarium and germarium of a worker bee ovary. In the vitellarium, Amvasa RNA is expressed in the nurse cells and oocyte. In the germarium, Amvasa RNA is restricted to the oocytes themselves, except for the last oocyte/ nurse cell group, where Amvasa is expressed in some of the nurse cells. C) Magnification of the germarium shown in B under DIC optics showing Amvasa expression in germ-cells and in the last group of nurse cells (arrowed) D) The tip of the germarium and the terminal filament of a worker bee ovary stained for Amvasa RNA. Amvasa expression appears in a subset of cells in each tissue, presumably PGCs. E and F) Magnification of the beginning of the terminal filaments of a worker bee ovary stained for Amvasa RNA and using the nuclear dye DAPI under brightfield (E) and fluorescence (F) optics. Amvasa RNA is seen in a subset of cells in this region. The terminal filament cells (arrowed) have no Amvasa expression. G and H) a region of terminal filament from a worker bee ovary stained for Amvasa, and using the nuclear dye DAPI under brightfield (G) and fluorescence (H) optics. Cells expressing Amvasa can be seen surrounded by non-staining cells. Amvasa expression quenches the nuclear signal in these images, so bright spots of DAPI fluorescence indicate unstained nuclei.