Being diploblastic organisms, with two germ layers of ectoderm and endoderm separated by an extracellular matrix (ECM) of mesoglea, they are among the simplest animals at the tissue level of organization. They are dated back to about 700 million years and are considered a sister group to the Bilateria. It highlights the importance of numerous stage-specific transcription factors in driving morphological and functional changes throughout this complex metamorphosis, and is expected to be a valuable resource to the community.Ĭnidarians, such as coral, sea anemone, jellyfish and hydra, are distributed worldwide and play important roles in shaping marine ecosystems. This study provides the first scyphozoan transcriptome covering the entire developmental trajectory of the life cycle of Aurelia. Finally, we identified the transcription factors participating in the Aurelia life-cycle and found that 70% of these 487 identified transcription factors were expressed in a developmental-stage-specific manner. The C元90-like gene, suggested to act as a strobilation hormone, was also highly expressed in the advanced strobila of the Red Sea species, and in the medusa stage we identified betaine-homocysteine methyltransferase, an enzyme that may play an important part in maintaining equilibrium of the medusa’s bell. Specific transcripts related to sensory functions were found in the strobila and the ephyra, whereas extracellular matrix functions were enriched in the medusa due to high expression of transcripts such as collagen, fibrillin and laminin, presumably involved in mesoglea development. Free-swimming planulae were found highly enriched for functions related to cilia and microtubules, and the drastic morphogenetic process undergone by the planula while establishing the future body of the polyp may be mediated by specifically expressed Wnt ligands.
Transcript expression profiling yielded clusters of annotated transcripts with functions related to each specific life-cycle stage.
ResultsĪ de novo transcriptome was assembled from Illumina RNA-Seq data generated from six stages throughout the Aurelia life cycle. Here we provide the first comprehensive view of the entire complex life of the Aurelia Red Sea strain by employing transcriptomic profiling of each stage from planula to mature medusa. We need to go deeper.The moon jellyfish Aurelia aurita is a widespread scyphozoan species that forms large seasonal blooms. The only way to save our future is to move forward. "We’ve come this far, we can't turn back now. Don't you think if there was some freshwater spring, we would have found it by now?” “But sir, we've gone deeper than any other ship's ever been before, we've fought blind horrors, and other nightmares. Nuhura, the ship’s communicator speaks up. But if we don't finish this mission, there's not going to be a home to go back to." It's time for a few words of encouragement. Spulu and Checker, the gunners, at their posts. I sit at the captain's wheel, guiding the ship through treacherous canals of coral. The fate of the world rests on our shoulders. Today might be the day this mission finally breaks them.īut I can't let that happen. Desperate and despairing, I don't know how much longer they can last. It's gotten us this far, but my crew is another story. We've sailed through cursed, infected and dark depths. Capricorn, we have traveled deeper than any other ship. Our mission, is to search for a drinkable water source, some underground freshwater flow that scientists have said might be found deep, near the ocean floor.Ĭommanding the SS. My crew and I have been fighting against them for over 15 years, but we're fighting a losing battle. They swarm the lakes, and stalk the seas. The creatures who live in the water now, have undergone horrendous mutations, and area terror to humankind. Nuclear waste has made the planet's water undrinkable.