Figure 8

Nanos1A and Nanos1B proteins share a similar expression profile in dogfish ovary. Immunohistochemistry has been performed on dogfish ovaries paraffin sections to detect Nanos1A (A–D, higher magnification in a–d) and Nanos1B (A’–D’, higher magnification in a’–d’). 3,3′-diaminobenzidine (DAB) was used for the revelation. E and E’ illustrate the negative control. The Nanos1A protein was detected in primary oocytes from primordial follicles (around 100 µm in diameter, A,a) to early vitellogenic follicles (around 500 µm in Ø, C,c) in the cytoplasmic and nuclear (N) compartments. Staining in oocytes became progressively undetectable whereas it appeared in granulosa (GC) and outer theca cells (oTC) of early (C,c) and more advanced vitellogenic follicles (>2 mm in Ø, D,d). Similarly, Nanos1B was detected in oocytes of primordial follicles (A’,a’). In previtellogenic follicle (B’b’), Nanos1B presented a major expression in oocyte nucleus (N). Finally, Nanos1B was observed in granulosa cells (GC) and outer theca cells (oTC) in vitellogenic follicles (C’,c’ and D’,d’). BL: basal lamina, GC: granulosa cells, iTC: inner theca cells, N: nucleus, Oo: primary oocyte, oTC: outer theca cells, ZP: zona pellucida.