Social interactions affect the behavior of organisms from bacteria to man. An important aspect of social interaction is communication. Bacteria utilize small molecules to communicate between each other. In many species of bacteria, these chemical signals tend to rapidly evolve to form different communication channel, i.e – a signal made by one strain of bacteria would not be sensed by another. This process requires the co-evolution of the signal molecule and its receptor and hence serves to elucidate the general problem of co-evolution under social selection. Our previous work indicated that the strong evolution of this system is dependent (or at least facilitated) by the selection on multiple levels of organization – the gene itself, it host bacterium (and sometime a host DNA parasite residing within the host bacterium), and the bacterial community. The importance for selection on multiple levels to the evolution of complex traits is widely discussed, but lacks concrete good model systems where it can be observed.
Studying bacterial communication has both direct benefit for society, as many bacteria utilize it to control their virulence. It also provides a general avenue for our basic understanding of the evolution of complex social traits in a relatively simple and experimentally amenable model system.
The aims of the grant where to:
1. Understand the scope of molecular diversity of a model bacterial communication system. This is to be done using advanced molecular screening techniques and high-throughput sequencing.
2. Understand the impact of ecology on selection on multiple scales. Especially understanding the effect of spatial organization within a community and horizontal transfer.
3. Understanding the molecular paths which allow diversification of communication system in the above mentioned ecologies.