We and others have shown that the upstream FA core complex is required for replication-dependent activation (monoubiquitination) of the downstream FANCD2 protein in response to DNA damaging agents that stall the replication fork. Our lab could also demonstrate that depletion of FA proteins from Xenopus laevis egg extracts results in accumulation of chromosomal breaks during replicative DNA synthesis.
To further elucidate FA pathway function(s) in the replication-coupled DNA damage response I am interested in determining which DNA repair intermediates lead to specific recruitment and activation of the FA proteins. I am currently developing an activation assay in Xenopus egg extracts to test DNA minisubstrates for their ability to recruit and activate the FA core complex and/or FANCD2. Within the same experimental setting, I am using single-protein depletion strategies to investigate how the FA pathway is intertwined with other central DNA repair pathways in the DNA structure-specific damage response.