EVALUATING THE INTERACTIONS BETWEEN SMALL AND GIANT DNA VIRUSES THROUGH THE INVESTIGATION OF ENDOGENOUS VIRAL ELEMENTS WITHIN THE GENOMES OF SINGLE-CELLED EUKARYOTES

Single-Celled Eukaryotes (otherwise characterized as Protists) compose roughly 50% of all oceanic biomass and thus play a pivotal role in nutrient cycling throughout our oceans. Recent studies have shown that diverse viruses exert top-down control over these protist populations, influencing their dynamics and biogeochemical fate. Giant viruses (GVs) within the phylum Nucleocytoviricota are among the key viral "predators” of protists. Recently it has been shown that smaller DNA viruses from the phylum Preplasmiviricota, namely virophages (VPs) and polinton-like viruses (PLVs) compete with GVs for resources during infection; leading to lower replication success of GVs. However, due in part to difficulties culturing both protists and their associated viruses, the true extent of interactions between the VP-PLV group and GVs is currently unknown. Both GVs and VP-PLVs are known to integrate their complete or partial genomes into the genomes of their protist hosts. We have developed and leveraged bioinformatic approaches to identify the GV and VP-PLV signatures in over 650 sequenced protist genomes. By examining both full virus genomes (VP and PLVs) and genome fragments (GVs) integrated within these protist genomes, we identified possible virus-protist interactions and interactions between GV and VP-PLV members. These results will be key for deciphering some of the complexity within the interactions of giant viruses with both their protist hosts and viral competitors in nature.

Presentation Preference: Either

Primary Presenter: Danae Stephens, University of Miamii (dcs186@miami.edu)

Authors:

Danae Stephens, University of Miami  (dcs186@miami.edu)

Mohammad Moniruzzaman, University of Miami  (m.monir@miami.edu)