Characterizing Sleep in C. elegans with Orsay-Infection

Paul using microscope




Associate Professor of Neurology

Project Summary

Sleep is a mysterious behavior that is observed from simple worms to complex humans. Human sleep is very rhythmic, but sickness can disrupt regularity. What causes this sleep response and how does improve health? Although we all sleep every day, sleep is not very well understood. We used C. elegans as a model for infection and sleep. This tiny roundworm is a great model organism for sleep since they sleep in response to stressors like infection. They also are great for developing new experiments since their lifespan is short and maintenance is easy. Many of the sleep experiments conducted needed optimizing; worms made this possible to do in a single summer.

After conducting various assays, using genetics and  counting, we find that worms infected with Orsay virus sleep more. A single neurons called ALA is required for infection-induced  sleep. We find that sleepless worms die earlier in adulthood compared to sleeping worms. We hypothesized that viral response is increased with sleep elongating lifespan, but found that pathogen response and viral infection rate remains the same. We will continue exploring this question by comparing energy stores between sleeping and sleepless worms. Other areas of further research are to investigate other behavioral differences between infected sleeping and sleepless worms.

The College Alumni Society Research Grant has given me the opportunity to solidify my understanding of sleep in C. elegans and realize the gaps of knowledge in the field. I have too many exciting question about sleep. This summer, I learned how to design experiments like quantifying pumping quiescence and challenges of optimizing new assays like the thermotaxis assay. This summer made me realize that I love research. I found that my curiosity is a huge motivator. Once I immerse myself in the field and find gaps in knowledge, I want to fill them in. I’m very excited to take research to a professional level.

I will be continuing this research in the coming school year looking at another behavior called thermotaxis. Worms will move to their preferred temperature if the surroundings are too hot or cold. This movement is called thermotaxis. Since worms are ectotherm, their internal temperature is dependant on the environment. This behavior could be related to mounting a fever when sick. Worms could mount a behavioral fever when infected by moving to warmer temperatures? This will expand our understanding of how worms fight off infection.