Discovery of Novel Gene Candidates involved in Orsay Virus Replication in C. elegans

Student Classification


Faculty Mentor

Dr. Robert Newman



Document Type


Publication Date

Fall 2018


Until the discovery of Orsay virus, there were no known viruses found to naturally infect the nematode Caenorhabditis elegans. Orsay virus infection in C. elegans provides a unique model to effectively study virus-host interactions in a laboratory setting. Upon infection, Orsay virus exhibits a subsequent decrease in the intracellular lipid droplet area within the intestinal cells of C. elegans. Our previous results lead us to believe that the C. elegans lipid droplets are important for the replication of Orsay virus, so we hypothesize that decreasing the intracellular lipid abundance within C. elegans intestinal cells will lead to a decrease in Orsay virus replication. To this end, we performed an RNA interference screen, which utilized exogenous feeding RNAi to knockdown target genes involved in lipid production and the lipophagy pathway. Total Orsay virus replication was quantified via qRT-PCR, and results were normalized to rps-20, a cellular gene unrelated to Orsay virus infection. In parallel, C. elegans that have undergone RNAi knockdown were fluorescently stained with Lipidtox and Nile Red. C. elegans contain two primary lipid storage granules, neutral lipid droplets and lysosome-related organelles, so using Lipidtox and Nile Red was necessary to show the overall distribution of lipid storage granules as compared to control worms that had not been subject to RNAi. Our results illustrated that one gene known as sbp-1, a sterol regulatory element-binding protein involved in lipid metabolism, confers a ~2.5-log decrease in Orsay virus replication. These studies show a correlation between decreased intracellular lipid abundance and decreased Orsay virus replication.

This document is currently not available here.