Coevolutionary genomics: Drosophila-Spiroplasma interactions

Nature is full of interactions between members of different species. Sometimes these interactions are mutually beneficial (for instance, an aphid requires bacteria to make amino acids); in other cases, one party benefits at the expense of another (for instance, a parasite that lives in a host). New parasite-host interactions are establishing all the time, as parasites come into contact with new host species. However, on the majority of occasions, these are transient-the parasite dies in the new host, or is not maintained as it cannot transmit with a sufficient rate. On other occasions, they produce dramatic (and significant) epidemics. We are interested in what causes the success (and failure) of new interactions. In this project, we seek to establish the extent to which induction of host defence and other responses is associate with the failure of new interactions (and therefore, find out what goes 'right' for the parasite in successful ones). The project will use the recently completed fruitfly genome to give us new insights. This completed genome has allowed the creation of chips, upon which we can simultaneously measure the rate of expression of every gene in the genome. We will test if parasites that struggle to survive in Drosophila are less hidden from the host, on a genome-wide basis, than those that are successful.