Comparative gene expression analysis based on RNA sequencing for the identification of host plant adaptation mechanisms in Chrysomelina leaf beetles

To study sequestration of defensive compounds and the adaptation of chemosensory proteins regarding host plant shift, the first focus of my thesis: De novo assembling the transcript libraries of three non-model insects (Phaedon cochleariae, Chrysomela populi and Chrysomela lapponica) by applying RNA-sequencing technology without genome information. Second focus is (re)identification and characterization of ATP-binding cassette transporters in C. populi, beta-glucosidase in three leaf beetles and chemosensory proteins in willow and birch populations of C. lapponica. Third focus is tissue expression profiling analysis of the above investigated genes. The comparison analysis among tissues or populations facilitates me to study the high expressed genes that may play an important role in the molecular process. The phylogenetic trees were calculated to characterize the relationships and propose a function for these beetle proteins.