ABSTRACT: Profiling of the embryonic Atlantic halibut (Hippoglossus hippoglossus L.) transcriptome reveals maternal transcripts as potential markers of embryo quality
Project description:Commercial Atlantic halibut (Hippoglossus hippoglossus) farming is restricted by variable oocyte quality, slow growth, and early maturation of male fish. Maternally transferred components regulate early developmental processes; therefore, they have an effect on the future development of an embryo. We profiled components of the transcriptome involved in immune defence as well as germline and muscle development during early developmental stages: 8-cell embryos, germ ring stage, 10-somite stage, and hatched embryos using a 10k oligonucleotide array and quantitative real-time PCR to specifically identify transcripts useful as molecular markers of embryo quality.
Project description:This study investigates transcriptomic changes across early embryonic development in Atlantic halibut (Hippoglossus hippoglossus), spanning stages from unfertilized eggs to late epiboly. RNA-seq was performed on whole embryos from three females at seven developmental stages to characterize maternal mRNA provisioning and zygotic genome activation. The data provide a comprehensive overview of gene expression dynamics during halibut embryogenesis and represent a resource for understanding early developmental regulation in teleosts.
Project description:RNA-seq analysis examining the effects of post-ovulatory aging on gene expression in Atlantic halibut (Hippoglossus hippoglossus) eggs. Eggs from one female were stored at 6°C for 0, 1, 2, 4, 6, or 12 hours before fertilization (t0-t12). RNA was extracted from four developmental stages: unfertilized eggs (UF), 8-cell stage (8C), blastula stage (BL), and 50 degree-days (50dd). Three technical replicates were collected for each stage and timepoint combination, resulting in 72 samples total (4 stages × 6 timepoints × 3 replicates). The study reveals that post-ovulatory aging primarily disrupts transcriptional programs at the mid-blastula transition, with significant downregulation of genes involved in axis formation, organogenesis, and developmental patterning. This dataset supports the findings that the BL stage is the critical failure window for post-ovulatory aged eggs
Project description:Egg quality is of pivotal importance in biomedicine, agriculture, ecology and environmental science because of its tremendous influence on reproductive success or failure in all animals. Despite species specific differences in physiological aspects of early development, the evolutionary conserved stereotypical procedure of cellular events, led us to investigate whether these findings are common with marine fish species of aquaculture interest. Atlantic halibut (Hippoglossus hippoglossus) is a highly prized species in global fish markets with increasing demand to its production. The objectives of this study were 1) to reveal the proteomic profiles of good versus poor quality halibut eggs, 2) to identify proteins that can serve as egg quality markers, and 3) to discover molecular mechanisms determining egg quality using a combination of quantitative proteomics workflows, tandem mass tags (TMT) labeling and parallel reaction monitoring (PRM).
