Analysis Of High-throughput Omics Data From The Symbionts Of Sponges

Many sponges harbor a great diversity of symbiotic microorganisms from the three domains of life, i.e. Archaea, Bacteria and Eukaryota, within their mesohyl tissues. The ecological function of most microbes is not understood. As vast majority of sponge-associated microbes remains uncultivated, method of direct sequencing genome and transcript data, metagenomics and metatranscriptomics respectively, need to be introduced to investigate this problem.Transcriptomics is used to investigate gene expression at RNA level. Metatranscriptomics is used to investigate the type, structure and function of total transcripts expressed by all genomes at a certain point and environment,what's more, micro and their relationship in the community are also be studied. Metatranscriptomics has been an important tool to understand the gene and pathway related with some process of biological functions.Theonella swinhoei is a high microbial abundance sponge and is a rich source of bioactive natural products. We use the analysis of metatranscriptomics data from Theonella swinhoei as an example to construct the pipeline of analyzing metatranscriptomics data. We also do the first attempt to use metatranscriptomics data to do secondary metabolism analysis of sponge. We find Proteobacteria is the most abundant symbionts of Theonella swinhoei with 17.09% abundance. Functional analysis of Theonella swinhoei shows that a highly expression of SasA by Nitrosopumilales. What's more, after aligning with existing database of gene cluster, we find that onnamide polyketides biosynthesis is active in Theonella swinhoei. we found vitamin B6 metabolism was not completed by the sponge but its symbionts. In summary, our results enhance our knowledge about the bioactivities of microbial symbionts of sponges.