PD Dr. Frank Colditz
We are interested in the functional genomics of early infection responses of legume plants during symbiotic and pathogenic interactions to soil-borne microbes. We have chosen the model legume Medicago truncatula as host plant since a variety of genomic tools are available for this legume species. Our investigations consider the symbioses to rhizobial bacteria as well as to arbuscular mycorrhiza (AM) fungi. For comparison of molecular response patterns that differ between symbiosis and pathogenesis, we also investigate the interaction of M. truncatula towards the root-pathogenic oomycete Aphanomyces euteiches. Experimental techniques comprise mainly proteomic tools which are combined with RT-PCR –based expression analyses. Candidate genes are functionally characterized in M. truncatula transgenic roots via RNAi gene silencing approaches.
Characterization of the Rac1 GTPase MtROP9 in Medicago truncatula
RAC/ROP proteins are plant-specific small GTPases that function as molecular switches within elementary signal transduction pathways including also the regulation of ROS (reactive oxygen species) generation during early microbial infection via activation of NADPH oxidase homologues of plants termed RBOH (repiratory burst oxidase homologue). We are currently investigating the role of Medicago truncatula small GTPase MtROP9, orthologous to M. sativa Rac1, via an RNA interference silencing approach.