Proteins involved in attack and defence in Zygomycete-aphid interactions

Fungi within the order Entomophthorales (Zygomycota) are obligate biotrophic pathogens of insects. Initially, the fungi penetrate the cuticle of their host, where after they grow with a protoplast-like morphology within the host, slowly degrading and eventually killing it. We have performed a secretome study of field collected grain aphids (Sitobion avenae) in early stages of infection with entomophthoralean fungi using the transposon assisted signal trapping (TAST) technology (Becker et al. 2004, J Microbiol Methods 57, 123-133), thereby discovering a series of secreted enzymes of the pathogens and defense related proteins of the host. Now, selected proteins are being produced in an expression host for further studies. The conservation of the fungal secreted proteins in the species dominating the collected material, namely Pandora neoaphidis, Entomophthora planchoniana and Conidiobolus obscurus, and additional related fungi are under investigation. We anticipate that our work will shed light on this highly specialized group of fungi that has attracted substantial attention as potential bio-control agents.