“…Similarly, Deletions in PCNA, RPA, and the Bloom protein (BLM), a 3'-5' helicase can also increase CNG repeat expansion or deletion, which reportedly interacts with FEN-1 in cleaving flaps. Recently NucS from Pyrococcus abyssi was found to be the equivalent of FEN-1 that cleaves the flapped DNA in Okazaki frangment processing in the lagging strand DNA replication (Ren et al, 2009;Creze et al, 2011). SLX1 and SLX4 are other structure-specific endonucleases acting as heteromer that cleave branched DNA substrates, particularly simple-Y, 5'-flap, or replication fork structures.…”