Universitą degli studi di Pavia

The main goal of my research is to unravel the DNA-repair network involving Tyrosyl-DNA phosphodiesterase 1 (TDP1) in model legume Medicago truncatula. 8-oxo-dG is a major byproduct of oxidative damage of DNA which is able to bound irreversibly the enzyme Topoisomerase I (Topo I) causing impairing of replication, transcription and nicking of DNA molecule. TDP1 activity is specific in resolving blocked Topo I enzyme, while this repair pathway is well known in animal organisms, this function is still poor understood in plants which have been proven to have two isoform of this enzyme. To study the role of TDP1 in M. truncatula a loss-of-function approach was chosen, using ihpRNAi and Agrobacterium-mediated gene transfer I successfully managed to generate plants showing reduced level of TDP1. Among regenerated plants lines showing a severe impairment of growth were selected to be further characterized, currently I am studying expression profiles, DNA damage accumulation, oxidative stress response as well as cellular morphology. The main goal of my research is to provide new information on oxidative damage and DNA repair in plants which can be used to obtain organism tolerant to a wide range of environmental stresses.
I am also studying in collaboration with prof. G. Rossi and Dott. A. Mondoni (Lombardy Seed Bank, Pavia) the response to ageing in seeds of different Silene vulgaris ecotypes to unravel molecular mechanisms which regulates metabolism of seed stored in seed banks and the subsequent release of dormancy. Another aspect of my research involves the response to gamma radiation in plant system like Petunia x hybrida and other ornamental crops and white poplar cell suspension to acquire new information on DNA repair mechanism and adaptive response. These results will be used to set up new mutational breeding protocols and to improve tolerance to abiotic stresses. Knowledge coming from this parallel works is addressed to be applied at my studies on M. truncatula.