Table 1.
Summary of developmental progression during oogenesis in D. melanogaster, calanid copepods and N. flemingeri.
| Biological process | Genes | Species | ||
|---|---|---|---|---|
| D. melanogaster | Calanoid | N. flem | ||
| Budding of the egg chamber from the germarium | Stage 1 | Wk0 | ||
| Germline development Polarization/Terminal follicle cell | Cell-interaction (innexin, nanos, delta) |
Stage 2–6 | OS0 | Wk1 |
| Oocyte polarity-start | Gurken (signaling) | Stage 7 | OS1 to early OS2 | Wks2–4 |
| Oocyte polarity-end Vitellogeneis 1 | MTOC (bicaudal, spire, cappuccino) Epidermal growth factor |
Stage 8–10 | Late OS2 to OS3 | Wks4–6 |
| Vitellogenesis 2 Cytoplasmic dumping | Maternal proteins (tudor, pumilio, torso) | Stage 11 | OS3–OS4 | Wk7 |
| Development completed Fertilization | Stage 14 | OS4 | — | |
Stages of oogenesis (Stage 1–14) in D. melanogaster and corresponding developmental processes and changes in gene expression are juxtaposed to oocyte development (OS0 to OS4) in calanoid copepods. Proposed correspondence with the developmental progression observed in N. flemingeri females during emergence from diapause are shown in the last column.