This domain represents the C-terminal region of the Replication stress response SDE2, a genome surveillance factor. It contains the DNA-binding SAP domain, frequently found in proteins involved in DNA repair. SDE2 C-terminal domain must be cleaved from its N-terminal at a diglycine motif within the ubiquitin-like fold, after Proliferating cell nuclear antigen (PCNA) interaction. This generates a functional protein that negatively regulates damage-inducible PCNA monoubiquitination, which then is proteolytically degraded to allow S phase progression and replication fork recovery in response to DNA damage [1].

1: PCNA-Dependent Cleavage and Degradation of SDE2 Regulates Response to Replication Stress. Jo U, Cai W, Wang J, Kwon Y, D'Andrea AD, Kim H; PLoS Genet. 2016;12:e1006465. PMID:27906959