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The ATM/ATR kinases and the Mre11 (Mre11-Rad50-Nbs1) protein complex are central players in the cellular DNA damage response. Here we characterize possible interactions between Aspergillus nidulans uvsB- ATR and the Mre11 complex (scaANBS1). We demonstrate that there is an epistatic relationship between uvsBATR, the homolog of the ATR/MEC1 gene, and scaANBSI, the homolog of the NBS1/XRS2 gene, for both repair and checkpoint functions and that correct ScaANBS1 expression during recovery from replication stress depends on uvsBATR. In addition, we also show that the formation of UvsC foci during recovery from replication stress is dependent on both uvsBATR and scaANBS1 function. Furthermore, ScaANBS1 is also dependent on uvsBATR for nuclear focus formation upon the induction of DNA double-strand breaks by phleomycin. Our results highlight the extensive genetic interactions between UvsB and the Mre11 complex that are required for S-phase progression and recovery from DNA damage.