Fig. 2. Expression of Egg protein during oogenesis. Ovaries labeled with an antibody to Egg. The left panels show Egg alone, and the right panels show Egg (green) and DNA (red). (A) Germarium and stage 2 egg chamber. The regions of the germarium are labeled. In germ stem cells (white arrow), cystoblasts and dividing cystocytes, the protein is both cytoplasmic and nuclear. In 16-cell germline cysts, Egg is concentrated in the germ cell nuclei (white arrowhead). Egg is not detected in somatic cells at the tip of the germarium (magenta arrow), but is present at low levels in prefollicular cells, and follicle cells of stage 1 egg chambers (green arrow). (B) Stage 8 egg chamber. In mid- and late stages of oogenesis, Egg is present throughout the nurse cell nuclei, and localizes to distinct foci associated with the DNA in the oocyte nucleus (white arrow). Egg expression increases in the follicle cells, where the protein is nuclear (green arrow). G, germarium; nc, nurse cell nuclei; s2, stage 2 egg chamber.