ROLE OF FANCONI ANEMIA PROTEINS IN THE DYNAMICS OF DNA REPLICATION AND DNA REPAIR

Fanconi anemia (FA) is a genetic disorder characterized by congenital abnormalities, bone marrow failure and predisposition to cancer. FA proteins are suspected to function together with other proteins that are essential for cells to replicate damaged DNA molecules. In the presence of lesions in the DNA, one of the twelve FA proteins identified so far, FANCD2, relocates and accumulates with other DNA repair proteins to defined nuclear regions. In mammalian cells, the replication of the DNA initiates from specific sites, called origins of DNA replication, and proceeds until the entire genome has been replicated. FA proteins are required to replicate DNA accurately. To understand how this process is altered when FA proteins are disabled, we will isolate fibers of replicating DNA from Fanconi anemia deficient cells and compare them to DNA fibers isolated from normal cells. The DNA fibers will be stretched and fixed on glass slides and will be analysed using sophisticated microscopy techniques that will allow us to visualize replication defects. We will also analyse isolated FANCD2 proteins by electron microscopy to gain insights into the nature of its association with DNA. The proposed project will contribute to our understanding of the molecular defects that cause Fanconi anemia. This should facilitate the design of therapeutic interventions to limit the clinical manifestations of this desease. The goals of this project fit well with the mission of the Comitato Telethon, which supports rare genetic diseases that are usually not easily funded by private agencies.