Fig. 4. Temporal and tissue-specific expression in female internal genitalia. (A) Schematic of the internal female reproductive system. Modified, with permission, from Miller (Miller, 1950). (B) Expression profiles of two female genes (see Fig. 2 legend). (C, parts I-IV) In situ hybridization of wild-type and tud 5-day adult female reproductive tissues using probes derived from female (I,II) and male (III,IV) genes. I part a, II part a, and III parts a, h and i, are frozen tissue frontal sections of whole animals; all other images are from whole-mount in situ hybridization analysis. (I) Expression is seen in spermathecae (arrows) and parovaria (arrowheads) in wild-type (a-d) and tud (e) tissues. (II) Expression in nurse cells of stage 8-10 egg chambers (a-c); in follicle cells covering an early stage 14 egg chamber, including the dorsal appendage (arrowhead; inset is at a closer focal plane; d); in oviducts (e); in spermathecae of wild-type (f) and tud (g) tissues; and in sheath of the immature ovaries found in tud animals (g). (III) Expression of male-enriched mfas in female tissues (a-f): in follicle cells of stage 9-10 egg chambers (b,c); in sloughed off follicle cells of a later stage egg chamber (d); in parovaria (e); in fat tissue (f); and, sex-nonspecifically, in CNS (g,h). (IV) Expression of male-enriched prd in female fat tissue (a-c). Insets are digital magnifications unless otherwise noted.