Toxicity evaluation, toxin screening and its intervention of the jellyfish Phacellophora camtschatica based on a combined transcriptome-proteome analysis

Background: The application of multi-omics technologies provides a new perspective to solve three main problems including species identification, toxin screening and effective antagonist conformation in the studies of marine toxic jellyfish. Methods: A series of transcriptome-proteome based analysis accompanied with toxicity evaluations were performed for the ornamental jellyfish Phacellophora camtschatica. Results: Through combined morphological observation and Cytochrome c oxidase subunit Ⅰ (CO1) molecular alignment, the sample jellyfish was identified as P. camtschatica. A total of 25,747 unigenes and 3058 proteins were obtained from the successfully constructed transcriptome and proteome, in which 6869 (26.68%) and 6618 (25.70%) unigenes, as well as 2536 (82.93%) and 2844 (93.00%) proteins were annotated against the databases of Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), respectively. The jellyfish displayed obvious in vivo lethal effects with significant increases of multi-organ functional indexes as well as in vitro activities. Total of 62 toxins from 120 toxin-related unigenes were screened including 16 metalloproteases, 11 phospholipases and others. Moreover, 11 toxins were further screened by using the erythrocyte model, where the zinc metalloproteinase nas-15-like (1) was the most abundant. Finally, Diltiazem greatly improved the survival rate while EDTA slightly prolonged the survival time in ICR mice. Conclusion: P. camtschatica is a poisonous jellyfish with diversified toxic components, in which metalloproteinase probably plays an important role in toxicities, and excessive Ca²⁺ entry may be the main mechanism of systemic lethal toxicity.