A potential tradeoff between feeding rate and aversive learning determines intoxication in a Caenorhabditis elegans host-pathogen system

Publication date: Available online 31 January 2020Source: Microbes and InfectionAuthor(s): Pallavi Velagapudi, Rachel Ghoubrial, Ratnavi Shah, Helana Ghali, Meghan Haas, Krunal S. Patel, Ashleigh Riddell, Christopher A. Blanar, Robert P. SmithAbstractDespite being the first line of defense against infection, little is known about how host-pathogen interactions determine avoidance. Caenorhabditis elegans can become infected by chemoattractant-producing bacteria through ingestion. The worms can learn to associate these chemoattractants with harm through aversive learning. As a result, the worms will avoid the pathogen. Evolutionary constraints have likely shaped the attraction, intoxication and learning dynamics between bacteria and C. elegans, but these have not been explored. Using bacteria engineered to express an acylhomoserine lactone chemoattractant and a nematicidal protein, we explored how manipulating the amount of attractant produced by the bacteria affects learning and intoxication in mixed stage populations of C. elegans. We found that increasing the production rate of the chemoattractant increased the feeding rate in C. elegans, but decreased the time required for C. elegans to learn to avoid the chemoattractant. Learning generally coincided with a decreased feeding rate. We also observed that the percentage of intoxicated worms was maximized at intermediate production rates of the attractant. We propose that interactions between attractant driven feeding rate and ...
Source: Microbes and Infection - Category: Infectious Diseases Source Type: research