SPO11 forms a dimer and each subunit cleaves a single strand of DNA, thus creating a double-strand break. After cleaving DNA, a SPO11 subunit remains covalently attached to each 5' end via a tyrosine residue. SPO11 is removed from the DNA by cleavage of single strands 3' to the attached SPO11. The products are a resected 5' end (protruding 3' overhang) and a covalent complex of SPO11 with an oligonucleotide.
3'-5'-exodeoxyribonuclease activity of MRX:SAE2 Complex [nucleoplasm]
endodeoxyribonuclease activity of MRX:SAE2 Complex [nucleoplasm]