Insights into viral community composition of the cnidarian model metaorganism Aiptasia using RNA-Seq data
- Published
- Accepted
- Subject Areas
- Bioinformatics, Genomics, Virology, Biosphere Interactions
- Keywords
- model organism, Aiptasia, Exaiptasia pallida, virus, RNA-Seq, metaorganism, holobiont, symbiosis
- Copyright
- © 2017 Brüwer et al.
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2017. Insights into viral community composition of the cnidarian model metaorganism Aiptasia using RNA-Seq data. PeerJ Preprints 5:e3343v1 https://doi.org/10.7287/peerj.preprints.3343v1
Abstract
Current research posits that all multicellular organisms live in symbioses with associated microorganisms and form so-called metaorganisms or holobionts. Cnidarian metaorganisms are of specific interest given that stony corals provide the foundation of the globally threatened coral reef ecosystems and their well-being strongly relies on forming mutualistic relationships with endosymbiotic algae of the genus Symbiodinium. So far, only few studies characterized viral diversity and the potential underlying functional importance to coral holobionts. Here we analyzed an existing RNA-Seq dataset of the coral model metaorganism Aiptasia CC7 (sensu Exaiptasia pallida) associated with aposymbiotic, partially populated, and fully symbiotic anemones with Symbiodinium to gain further insight into viral community composition and the relation to the algal endosymbiosis. Our approach included the selective removal of anemone host and algal endosymbiont sequences and subsequent microbial sequence annotation. Of a total of 297 million raw sequence reads, 8.6 million (~ 3%) remained after host and endosymbiont sequence removal. Of these, 3,293 sequences (paired-end read pairs) could be assigned as of viral origin. Taxonomic annotation shows that Aiptasia is associated with a diverse viral community consisting of 116 viral taxa covering 40 families. The viral community was dominated by viruses from the families Herpesviridae (12.00%), Partitiviridae (9.93%), and Picornaviridae (9.87%). Despite an overall stable viral community, we found that some viral taxa significantly changed in relative abundance when Aiptasia engage in a symbiotic relationship with Symbiodinium. Elucidation of viral taxa consistently present in all samples revealed an Aiptasia core virome of 15 viral taxa from 11 viral families that was comprised of many viruses previously reported in coral viromes. Our study provides a first insight into the viral community of Aiptasia. Aiptasia seem to harbor a diverse and overall stable viral community, although certain members change in abundance when the anemone host associates with its algal endosymbiont. However, the functional significance of this remains to be determined.
Author Comment
This is a submission to PeerJ for review.
Supplemental Information
Supp. Table S1. CSS normalized sequence counts for all annotated viruses
The viral spreadsheet is completed with genome organization information and information about respective hosts. A1M – A4M: aposymbiotic; I1M – I4M = partially populated (after 12 days of infection); S1M – S4M = fully symbiotic (fully infected, after 30 days of infection).
Supp. Table S2. Abundance changes of viruses associated with Aiptasia in relation to aposymbiotic, partially populated, and fully symbiotic anemones
Shown are viral taxa tested, ANOVA p-values (significant values in bold), and associated post-hoc Tukey tests, as well as assortment to the ‘increase’ and ‘decrease’ group.
Supp. Table S3. Aiptasia core virome and viromes associated with aposymbiotic, partially populated, and fully symbiotic anemones of Aiptasia
Only viruses present in 100% of each respective symbiotic state were considered. Viruses present across all samples comprise the core virome. Members of the core virome are highlighted in bold.