High temporal and spatial diversity in marine RNA viruses implies that they have an important role in mortality and structuring plankton communities

Abstract

Viruses in the order Picornavirales infect eukaryotes, and are widely distributed in coastal waters. Amplicon deep-sequencing of the RNA dependent RNA polymerase (RdRp) revealed diverse and highly uneven communities of picorna-like viruses in the coastal waters of British Columbia (BC), Canada. Almost 300 000 pyrosequence reads revealed 145 operational taxonomic units (OTUs) based on 95% sequence similarity at the amino-acid level. Each sample had between 24 and 71 OTUs and there was little overlap among samples. Phylogenetic analysis revealed that some clades of OTUs were only found at one site; whereas, other clades included OTUs from all sites. Since most of these OTUs are likely from viruses that infect eukaryotic phytoplankton, and viral isolates infecting phytoplankton are strain-specific; each OTU probably arose from the lysis of a specific phytoplankton taxon. Moreover, the patchiness in OTU distribution, and the high turnover of viruses in the mixed layer, implies continuous infection and lysis by RNA viruses of a diverse array of eukaryotic phytoplankton taxa. Hence, these viruses are likely important elements structuring the phytoplankton community, and play a significant role in nutrient cycling and energy transfer.

Metatranscriptomic reconstruction reveals RNA viruses with the potential to shape carbon cycling in soil

“…In combination, these observations suggest that virus and phage abundances are not solely determined by the presence of their hosts, but factors such as sporadic blooms, probably in part due to variation in viral resistance levels in the host population, lead to patchy distribution patterns for viruses in soil. These patterns are analogous to those documented in marine virus blooms, though the exact cause of these events are still unknown (11,61).…”

“…The majority of soil RNA viral work has been single-host focused, for agriculturally relevant crops (5) or crop pathogens (6). Environmental RNA virus studies have focused on less complex or more tractable systems such as marine environments and the human and animal gut (7)(8)(9)(10)(11). To our knowledge, no sequencing-based RNA viral community analyses have investigated soil.…”

Bridging the Gap between Knowing and Modeling Viruses in Marine Systems—An Upcoming Frontier

“…Recent findings have corroborated previous views on the roles of viruses in nutrient cycling and energy transfer, but also brought additional insights on how they may structure the phytoplankton community (Baudoux and Brussaard, 2005;Gustavsen et al, 2014). So far viruses have been reported to infect a wide variety of phytoplankton groups including diatoms (Shirai et al, 2008), dinoflagellates (Yuji et al, 2004), prasinophytes (Derelle et al, 2008), and cyanobacteria (Ortmann et al, 2002), among others.…”

Deep sequencing of amplified Prasinovirus and host green algal genes from an Indian Ocean transect reveals interacting trophic dependencies and new genotypes

“…Microbes are the most abundant organisms in the sea, where they shape the structure and function of ecosystems (Azam et al, 1983), but they are still one order of magnitude less abundant than microbe-infecting viruses (Suttle, 2005). Viruses are thus important players in microbial mortality and strongly influence biogeochemical cycles and the structure of host communities (Proctor and Fuhrman, 1990;Gustavsen et al, 2014). Marine microbes and their associated viruses are thought to have high dispersal capacities because of their abundance, (Finlay, 2002;Angly et al, 2006), although community composition might differ according to environmental conditions (Angly et al, 2006;Martiny et al, 2006).…”