Science Digest Chalk Talk: "How do parasites manipulate their hosts?"

Ales Bucek (Postdoctoral Scholar in Bourguignon Unit)

Abstract

Many parasites elicit in their host physiological and behavioral changes which are apparently beneficial for the parasite: rats infected by Toxoplasma lose their fear of cats, which increases the chance of Toxoplasma transmission to its definitive cat host; ants infected by Ophiocordyceps fungi climb up vegetation and bite into it in a death-grip which secures the infected ant body in place as a dispenser of fungal spores. Knowledge of the molecular mechanism by which parasites alter the host phenotype could help us understand how these manipulative strategies evolved and also uncover how the host organisms regulate their behavior and physiology. However, even for the two famous examples above, the "tools" used by parasites to manipulate their host remain rather unclear.
In this chalk talk, I will first briefly introduce what we know and don't know about parasitic manipulation. Then, I'd like to discuss with you my rather ambitious pursuit of this question and the first results of our study of the host-parasite system which encompasses a parasitic fly larva that changes ontogenetic development and behavior of termites.