Fig. 4. Hyzic expression during different stages of oogenesis. (A) Early stage 1 [stages according to Miller et al. (Miller et al., 2000)] of egg field formation, without a morphological sign of an oocyte but already devoid of Hyzic expression. (B) Stage 2 of oocyte development indicated by the swollen ectoderm in the upper part of the body column. (C) Stage 5, when most of the oocyte has already retracted from the eggfield. (D) Mature oocyte (stage 7). Note, that the former egg field is still completely devoid of Hyzic expressing cells.