Host-Bacteria-Virus Interactions in Caenorhabditis elegans

The factors governing transmissibility of viruses between susceptible hosts are not well understood. The discovery of Orsay virus and the experimental tractability of the C. elegans host enables the study of the determinants of virus transmission. Studies from mice and insects have demonstrated that bacteria influence viral infection and transmission. Here we used Caenorhabditis elegans and Orsay virus to screen a panel of bacteria to study their impact on virus transmission rates. We identified that exposure to and ingestion of these bacteria result in divergent bacteria-specific effects on transmission rate. Specifically, we observed that the presence of Pseudomonas aeruginosa and Pseudomonas lurida reduced transmission and infection rates relative to the standard laboratory diet of Escherichia coli OP50, whereas the presence and ingestion of Ochrobactrum species enhanced infection by Orsay virus. We observed that the inhibitory effect of P. aeruginosa and P. lurida was dependent on quorum- sensing pathways and the two-component response regulator gacA. We noted that Ochrobactrum ingestion into the intestinal lumen was important for its ability to enhance Orsay infection. Our data suggest there is a tripartite interaction between the Orsay virus, bacteria, and the C. elegans host that can strongly modulate virus transmission in a bacterial species-specific manner.

Name thesis:degree_name

Doctoral

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Biology

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2023

Author dc:creator

• Vassallo, Brian Gregory

Advisor dc:contributor.advisor

• Kim, Dennis H.

Statement dc:rights

• Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)
• Copyright retained by author(s)

Licence dc:rights.uri

• https://creativecommons.org/licenses/by-nc/4.0/

Handle dc:identifier.uri

https://hdl.handle.net/1721.1/153035

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/153035