DNA interstrand crosslink repair and chromatin remodelling

ended

DNA interstrand crosslinks can arise as a by-product of cellular metabolism and, if left unrepaired, they impede DNA replication and threaten genome integrity. Faulty repair of DNA interstrand crosslinks has been linked to Fanconi anemia (FA), a disease characterized by genomic instability and cancer predisposition. The mechanisms underlying DNA interstrand crosslink repair are not fully understood, and it is likely that key regulators of this pathway have yet to be identified. Further, as the proteins involved in DNA interstrand crosslink repair have mostly been profiled using cell-free systems, the impact of chromatin states on DNA interstrand crosslink repair is poorly understood. The main aims of this project are i) to profile the entire repertoire of proteins recruited to DNA interstrand crosslinks in human cells, and ii) to uncover and characterize chromatin proteins involved in DNA interstrand crosslink repair. First, I will develop a pull-down technique to biochemically isolate chromatin surrounding DNA interstrand crosslinks and I will employ it to quantitatively characterise the full spectrum of proteins recruited to these lesions in human cells. This approach has the potential to uncover new regulators of DNA interstrand crosslink repair, including numerous proteins with a function in chromatin biology. I will, then, complement and expand this biochemistry-based strategy using a live cell imaging approach, with the aim of uncovering nucleosome remodellers and histone chaperones recruited to DNA interstrand crosslinks. Finally, the function of new regulators will be dissected using a combination of state-of-the-art microscopy and gene targeting techniques. Together, this work will provide a comprehensive picture of the proteins involved in DNA interstrand crosslinks repair and will uncover mechanisms of chromatin remodelling associated to the repair of these lesions in human cells.