Global transcriptome analysis identifies regulated transcripts and pathways activated during oogenesis and early embryogenesis in Atlantic cod.
Bottom Line: During early vitellogenesis, several of the most upregulated genes are linked to nervous system signaling, suggesting increasing requirements for ovarian synaptic signaling to stimulate the rapid growth of oocytes.Highly upregulated genes during late vitellogenesis are linked to protein processing, fat metabolism, osmoregulation, and arrested meiosis.One of the genes with the highest upregulation in the ovulated egg is involved in oxidative phosphorylation, reflecting increased energy requirements during fertilization and the first rapid cell divisions of early embryogenesis.
Affiliation: Institute of Marine Research, Bergen, Norway.Show MeSH
Related in: MedlinePlus
Mentions: A range of genes were significantly upregulated from pre- to early-vitellogenic follicles (349), from early- to late-vitellogenic follicles (376), from late- vitellogenic follicles to ovulated eggs (149), from ovulated eggs to blastula embryos (30), and from blastula to gastrula embryos (657). The corresponding numbers for downregulated genes were 555, 532, 655, 10, and 396, respectively. In general, more transcripts of genes were downregulated than induced throughout oogenesis, with the largest difference detected from late-vitellogenic follicles to ovulated eggs, during which 506 more genes were downregulated then upregulated (Fig. 2). The smallest difference was observed from ovulated eggs to blastula, where 20 more genes were upregulated than downregulated (Fig. 2). From blastula to gastrula, many more genes were upregulated than downregulated (Fig. 2). The complete gene lists can be found in Supplemental material (Additional Files 1a–j).