This entry represents exonuclease 1 (Exo1) from eukaryotes. Exo1 is a 5'-3' exonuclease that functions in DNA mismatch repair (MMR), double-strand break repair, replication and recombination [, , ]. It also possesses a flap-endonuclease activity [, ].Budding yeast Exo1 has a paralogue known as Din7, which is involved in mitochondrial DNA repair and replication [].
This is the PIN domain found in animal exonuclease-1 (EXO1) and its paralogue from yeasts, Din7. EXO1 is a 5'-3'-exonuclease that functions in DNA mismatch repair (MMR), double-strand break repair, replication, recombination and telomere integrity [, , ]. It also possesses a flap-endonuclease activity [, ], being a member of the Flap endonuclease-like (FEN-like) family, which are structure-specific endonucleases capable of cleaving single-stranded DNA or RNA at the bifurcated end of a base-paired duplex. DIN7 is involved in mitochondrial DNA repair and replication [].PIN domains belong to a large nuclease superfamily, which share a common core fold consisting of a three-layered α/β/α core motif with a central, parallel five-stranded β-sheet. Its active site, possess invariant acidic amino acid residues and binds one or more divalent metal ions [, ].
