Building Cornell – Chile collaborations in marine science and metagenomics through exploration of viruses in the Chilean tunicate Pyura chilensis

Collaboration with Yoanna Eissler, Universidad de Valparaiso

Identifying viruses has traditionally involved isolation of infectious particles on cultivated host cell lines (i.e. tissue culture), which is problematic for marine organisms, since few appropriate cell lines exist and are entirely absent for some groups of marine animals. To circumvent this limitation, viral metagenomics, where virus particles are extracted from animal tissues, purified, and their DNA sequenced, does not rely on cell culture, and thereby provides an assessment of viral diversity within hosts for which cell lines are not available.  Sea squirts are important to ecosystem function – their filter feeding activities maintain the balance between bottom-associated animals and plants and contribute to downward sediment flux. The Chilean tunicate Pirua (Pyura chilensis) occurs in temperate waters off Chile and Peru, and is harvested for consumption by artisinal fisheries. We performed collaborative research to study the diversity and extent of viruses in piruas, involving Cornell and Universidad de Valparaiso scientists, in preparation for a wider research proposal to the National Science Foundation to study the ecological impact of tunicate viruses on ecosystem processes. Support from the Einaudi center funded travel by the Cornell  principal investigator to Chile to sample piuras and prepare tunicate tissues for metagenomic sequencing, for the DNA sequencing itself, and for the Universidad de Valparaiso principal investigator to come to visit Cornell University to assist in bioinformatics and genomics of tunicate viruses.

Work published from this project:

Gudenkauf BM, Hewson I (2016) “Comparative metagenomics of viral assemblages inhabiting four phyla of marine invertebrates” Frontiers in Marine Science https://doi.org/10.3389/fmars.2016.00023